bims-aporos Biomed News
on Apoptosis and reactive oxygen species
Issue of 2019‒06‒30
sixty-three papers selected by
Gavin McStay
Staffordshire University


  1. Int J Ophthalmol. 2019 ;12(6): 930-935
    Yiğit M, Güneş A, Uğuz C, Yalçın TÖ, Tök L, Öz A, Nazıroğlu M.
      AIM: To observe the protective effect of astaxanthin (AST) against hydroquinone (HQ) mediated cell death in the apoptotic cascade and evaluate intracellular Ca2+ release, caspase-3, and -9 activation, reactive oxygen species (ROS) production in ARPE-19 cells.METHODS: We cultured ARPE-19 cells in special mediums and performed MTT tests to determine protective effect of AST, before exposing the cells to HQ in an incubator. We analyzed intracellular Ca2+ release experiments, mitochondrial membrane depolarization, glutathione (GSH), glutathione peroxidase (GSH-Px) and ROS experiments, and apoptosis assay.
    RESULTS: ROS production ranges depend on the amount of cell death. We computed the correlation between ROS ranges and cell death by 20,70-dichlorofluorescein fluorescence, and Ca2+ levels by Fura-2-AM. HQ-induced cell death found out to rise ranges of caspase-3 and -9, and mitochondrial depolarization. These three steps were delayed by AST management.
    CONCLUSION: ARPE-19 cells are avoided from HQ-induced ROS production and caspase-3 and -9 activation by AST. AST may limit the range of caspase synthesis, Ca2+ release and excess production of ROS with antiapoptotic effect. This study proposes a new therapeutic approach for the treatment of age-related macular degeneration.
    Keywords:  ARPE-19 cell; apoptosis; astaxanthin; oxidative stress
    DOI:  https://doi.org/10.18240/ijo.2019.06.08
  2. Chem Biol Interact. 2019 Jun 19. pii: S0009-2797(19)30320-5. [Epub ahead of print]
    Luo Y, Wan Q, Xu M, Zhou Q, Chen X, Yin D, He H, He M.
      Ischemic preconditioning and pharmacological preconditioning are common strategies to prevent lethal myocardial injury, especially nutritional preconditioning (NPC). In this study, we investigated the effects of astragaloside IV (Ast), as an NPC agent, on myocardium suffered anoxia/reoxygenation (A/R) injury. Rats received 5 mg/kg Ast daily for 3 weeks by intragastric administration. Then, hearts were harvested and underwent A/R treatment using a Langendorff apparatus. Ast- pretreatment significantly promoted functional recovery of the myocardium, reduced infarct size, and oxidative stress, and decreased the apoptotic index. Similar findings were demonstrated in H9c2 cardiomyocytes that were pretreated with Ast for 24 h. Moreover, Ast-pretreatment significantly upregulated Bcl-2 expression, especially in mitochondria. The effects of Ast treatment against A/R injury were also reflected by increased antioxidant potential, inhibited reactive oxygen species (ROS) burst, increased oxygen consumption rate, maintained mitochondrial membrane potential (MMP), inhibited mitochondrial permeability transition pore (mPTP) opening, and prevented apoptosis. Selective inhibition of Bcl-2 by ABT-737 decreased myocardial injury protection of Ast. Ast-pretreatment resulted in NPC- related effects against A/R, and mitochondria may be the target of a cascade of events elicited by upregulating Bcl-2 expression, promoting translocation of Bcl-2 into mitochondria, maintaining MMP, inhibiting ROS bursts, thereby leading to recovery of mitochondrial respiration, preventing mPTP opening, decreasing cytochrome C release, preventing apoptosis, and ultimately alleviating myocardial injury.
    Keywords:  Anoxia/reoxygenation; Astragaloside IV; Bcl-2; Cardioprotection; Mitochondria; Nutritional preconditioning
    DOI:  https://doi.org/10.1016/j.cbi.2019.06.036
  3. Chemosphere. 2019 Jun 17. pii: S0045-6535(19)31366-9. [Epub ahead of print]234 682-689
    Yuan J, Kong Y, Ommati MM, Tang Z, Li H, Li L, Zhao C, Shi Z, Wang J.
      Bisphenol A (BPA) is widely used in the production of epoxy resins and polycarbonate plastics. Under harsh situations, these plastics likely desorb BPA, which then can seep into the environment. Various concentrations of BPA have been detected in most biological fluid. However, there is paucity of information on the detrimental effects of BPA and its subsequent cellular events in chronic kidney disease (CKD). Hence, in this in vitro study, we aimed to investigate the effects of BPA on renal epithelial cell activation, apoptosis, and DNA damage. Rhesus monkey embryo renal epithelial Marc-145 cells were exposed to 0, 10-1, 10-2, 10-3, 10-4, 10-5, and 10-6 M of BPA. Alterations in intracellular apoptosis, oxidative stress, and DNA damage were evaluated. The results showed that BPA decreased cell viability, superoxide dismutase (SOD) activity and glutathione (GSH) level, with concomitant increases in apoptosis related indices, lactate dehydrogenase (LDH) activity, reactive oxygen species (ROS) generation, thiobarbituric acid reactive substances (TBARS) content, and the rate of comet Marc-145 cells with a dose-dependent manner. The data indicated that increased oxidative stress, apoptosis and DNA damage in epithelial Marc-145 cells might play a pivotal role in the mechanism of BPA-induced nephrotoxicity.
    Keywords:  Apoptosis; Bisphenol A; DNA damage; Marc-145 cells; Nephrotoxicity; Oxidative stress
    DOI:  https://doi.org/10.1016/j.chemosphere.2019.06.125
  4. J Cell Biochem. 2019 Jun 24.
    Wu DM, Zheng ZH, Fan SH, Zhang ZF, Chen GQ, Lu J.
      BACKGROUND: Nuclear factor erythroid 2-related factor 2 (Nrf2) can alleviate diffuse axonal injury (DAI)-induced apoptosis by regulating expression of heme oxygenase-1 (HO-1), while sulforaphane (SFN) was shown to reduce oxidative stress by increasing the expression of Nrf2. Therefore, we aimed to investigate therapeutic effect of SFN in the treatment of DAI and the ability of SFN to reduce oxidative stress.METHODS: The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to observe the effects of H2 O 2 and SFN on cell viability. Fluorometric assay, Western blot analysis, and flow cytometry were conducted to validate the protective role of SFN in an animal model of DAI. In addition, the levels of malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were measured in DAI rats treated by SFN, while Western blot, immunohistochemistry assay, and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay were carried out to verify the effect of SFN in different animal groups.
    RESULTS: Cell viability was reduced by H2 O 2 in a dose-dependent manner, while the treatment by SFN significantly promoted cell growth. Meanwhile the administration of SFN effectively reduced the levels of caspase-3/poly(ADP-ribose) polymerase (PARP) activity increased by the H 2 O 2 treatment, indicating that the protective effect of SFN could be mediated by its ability to suppress caspase-3 activation and PARP cleavage. In addition, the SFN treatment reduced the intracellular reactive oxygen species (ROS) generation induced by H 2 O 2 . Moreover, the MDA levels of SOD/GPx activity in various rat groups showed the protective effects of SFN in DAI rats. It is suspected that the protective effect of SFN was exerted via the activation of the Nrf2/HO-1 signaling pathway. In this study, DAI and DAI + phosphate-buffered saline (PBS) groups also showed the presence of more TUNEL-positive cells compared with the sham-operated group, while the SFN treatment reduced the extent of neuronal apoptosis.
    CONCLUSIONS: By activating the Nrf2/HO-1 signaling pathway and reducing the activity of caspase-3, SFN reduces the apoptosis of neurons in brain trauma-induced DAI.
    Keywords:  HO-1; Nrf2; apoptosis; diffuse axonal injury; sulforaphane
    DOI:  https://doi.org/10.1002/jcb.29203
  5. Biochim Biophys Acta Gen Subj. 2019 Jun 20. pii: S0304-4165(19)30159-X. [Epub ahead of print]
    Nakmura T, Naguro I, Ichijo H.
      BACKGROUND: Iron is essential for many types of biological processes. However, excessive iron can be cytotoxic and can lead to many diseases. Since ferroptosis, which is an iron-dependent regulated form of necrosis, was recently discovered, iron and iron-catalysed oxidative stress have attracted much interest because of their sophisticated mechanism of cellular signalling leading to cell death and associated with various diseases.SCOPE OF REVIEW: In this review, we first focus on how iron catalyses reactive oxygen species (ROS). Next, we discuss the roles of iron in cell death and senescence and, in particular, the downstream signalling pathways of ROS. Finally, we discuss the potential regulation mechanism of iron as a therapeutic target for various iron-related diseases.
    MAJOR CONCLUSIONS: Both labile iron released from organelles upon various stresses and iron incorporated in enzymes produce ROS, including lipid ROS. ROS produced by iron activates various signalling pathways, including mitogen-activated protein kinase (MAPK) signalling pathways such as the apoptosis signal-regulating kinase 1 (ASK1)-p38/JNK pathway. These ROS-activated signalling pathways regulate senescence or cell death and are linked to cancer, ischaemia-reperfusion injury during transplantation and ageing-related neurodegenerative diseases.
    GENERAL SIGNIFICANCE: Iron overload damages cells and causes harmful effects on the body through oxidative stress. Thus, understanding the spatiotemporal availability of iron and the role of iron in generating ROS will provide clues for the suppression of ROS and cytotoxic redox-active iron. Moreover, elucidating the molecular mechanisms and signalling pathways of iron-dependent cytotoxicity will enable us to find novel therapeutic targets for various diseases.
    Keywords:  Apoptosis signal-regulating kinase 1 (ASK1); Cancer; Ferroptosis; Iron; Reactive oxygen species (ROS); senescence
    DOI:  https://doi.org/10.1016/j.bbagen.2019.06.010
  6. Eur J Med Chem. 2019 Jun 18. pii: S0223-5234(19)30572-0. [Epub ahead of print]179 26-37
    Song XD, Chen BB, He SF, Pan NL, Liao JX, Chen JX, Wang GH, Sun J.
      PDT is a well-established therapeutic modality for many types of cancer. Photoluminescent cyclometalated iridium(III) complexes are one of the most commonly used classes of organometallic compounds with potential beneficial applications in bioimaging and as promising anticancer agents. In the present study, three new cyclometalated iridium(III) complexes (Ir1-Ir3) containing guanidinium ligands were found to exert excellent cytotoxic effects on different types of cancer cells upon light irradiation at 425 nm. Notably, Ir1 conferred almost no dark toxicity (IC50 > 100 μM) to HepG2 cells, but the value decreased by 387-fold to 0.36 μM following 10 min of light irradiation (425 nm). Further mechanistic investigation revealed that complex Ir1 could induce apoptosis via the activation of reactive oxygen species (ROS)-mediated mitochondrial signaling pathways in the presence or absence of light irradiation. In vivo studies demonstrated that Ir1 significantly inhibited tumor growth in HepG2 xenograft-bearing mice under light irradiation at 425 nm. Taken together, these findings indicate that designing PDT-based Ir(III) complexes may hold a great deal of promise for anticancer drug development.
    Keywords:  Apoptosis; Cytotoxicity; Ir(III) complex; Mitochondria; PDT
    DOI:  https://doi.org/10.1016/j.ejmech.2019.06.045
  7. Med Sci Monit. 2019 Jun 22. 25 4639-4647
    Wang C, Li S, Ren H, Sheng Y, Wang T, Li M, Zhou Q, He H, Liu C.
      BACKGROUND Breast cancer is one of the most malignant tumors worldwide. The natural flavonoid diosmetin has been reported to exhibit various pharmacological activities, including anti-cancer effects. This study aimed to investigate the anti-breast cancer effects of diosmetin on MDA-MB-231 cells and to explore the underlying molecular mechanisms of cell apoptosis. MATERIAL AND METHODS The MDA-MB-231 cells were incubated with diosmetin for 24 h. Then, cell viability and lactate dehydrogenase (LDH) leakage were detected using CCK-8 and LDH assay kits, respectively. Inverted fluorescence microscopy and flow cytometry were used to measure the mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS). Cell apoptosis and cell cycle were determined by flow cytometry. The expressions of apoptosis and cell cycle-related genes were determined by Western blotting and qRT-PCR. RESULTS The results revealed that diosmetin exerts significant cytotoxic effects on MDA-MB-231 cells, as indicated by decreased cell viability, increased intracellular ROS accumulation and LDH release, as well as cell cycle arrest in G0/G1 phase, inducing mitochondrial dysfunction and apoptosis. Moreover, diosmetin treatment significantly downregulated the expression levels of Bcl-2 and Cyclin D1, and upregulated that of p53, Bax, caspase 3, cleaved caspase 9, and cleaved caspase 3. CONCLUSIONS These findings demonstrate that diosmetin has anti-proliferative and pro-apoptotic activities against MDA-MB-231 cells via cell cycle arrest and the mitochondria-mediated intrinsic apoptotic pathway. Our results extend the understanding of the anti-tumor mechanism of diosmetin and suggest that it may be of use as an active natural agent for the prevention or treatment of human breast cancer.
    DOI:  https://doi.org/10.12659/MSM.914058
  8. Microcirculation. 2019 Jun 22. e12577
    Bihari A, Chung KA, Cepinskas G, Sanders D, Schemitsch E, Lawendy AR.
      OBJECTIVE: Limb compartment syndrome (CS), a complication of trauma, results in muscle necrosis and cell death; ischemia and inflammation contribute to microvascular dysfunction and parenchymal injury. Carbon monoxide releasing molecule-3 (CORM-3) has been shown to protect microvascular perfusion and reduce inflammation in animal models of CS. The purpose of the study was to test the effect of CORM-3 in human in vitro CS model, allowing exploration of the mechanism(s) of CO protection and potential development of pharmacologic treatment.METHODS: Confluent human vascular endothelial cells (HUVECs) were stimulated for 6 hours with serum isolated from CS patients. Intracellular oxidative stress (production of reactive oxygen species (ROS)) apoptosis, trans-endothelial resistance (TEER), polymorphonuclear leukocyte (PMN) activation and transmigration across the monolayer in response to the CS stimulus were assessed. All experiments were performed in the presence of CORM-3 (100μM), or its inactive form, iCORM-3.
    RESULTS: CS serum induced a significant increase in ROS, apoptosis and endothelial monolayer breakdown; it also increased PMN superoxide production, leukocyte rolling and adhesion/transmigration. CORM-3 completely prevented CS-induced ROS production, apoptosis, PMN adhesion, rolling and transmigration, while improving monolayer integrity.
    CONCLUSION: CORM-3 offers potent anti-oxidant and anti-inflammatory effects, and may have a potential application to patients at risk of developing CS. This article is protected by copyright. All rights reserved.
    Keywords:  CORM-3; acute limb compartment syndrome; apoptosis; carbon monoxide; cytokines; endothelial integrity; inflammation; microvascular dysfunction; reactive oxygen species
    DOI:  https://doi.org/10.1111/micc.12577
  9. Cell Death Discov. 2019 ;5 100
    Araveti PB, Srivastava A.
      Bovine tropical theileriosis is a tick-borne disease, caused by Theileria annulata which is a protozoan parasite that resides within the B-cells and macrophages. T. annulata is a unique parasite that can transform bovine leucocytes which leads to the cancer hallmarks in the infected cells. Previously, curcumin has been shown to possess multiple pharmacological activities such as anti-inflammatory and anti-cancer activities. In this study, we demonstrated that curcumin inhibits the proliferation of Theileria-transformed bovine leucocytes by promoting apoptosis and autophagy. The transcriptome analysis of curcumin treated cells showed that the genes involved in cell death and autophagy are also differentially regulated. We further elucidated the mechanism of action of curcumin on Theileria infected bovine cells. We found that curcumin induced the generation of reactive oxygen species (ROS) which activated caspase 8 and destabilized the mitochondrial membrane potential leading to the release of cytochrome c from mitochondria. This subsequently led to the activation of caspase 3 and PARP cleavage, finally leading to apoptosis in the infected cells. Furthermore, curcumin induced the process of autophagy which was characterized by the formation of acidic vesicular organelles, LC3B accumulation with lysosome inhibitor, E64d, and the presence of autophagosomes as visualized by transmission electron microscopy (TEM). Curcumin treatment suppressed the mTOR and increased the expression of autophagy-related proteins. We also found that N- acetylcysteine, an inhibitor of ROS, could rescue the infected cells from curcumin induced apoptosis and autophagy mediated cell death. Intriguingly, curcumin had no effect on uninfected bovine PBMCs. Altogether, these data suggest the therapeutic potential of curcumin against bovine tropical theileriosis.
    Keywords:  Antiparasitic agents; Parasitic infection
    DOI:  https://doi.org/10.1038/s41420-019-0180-8
  10. Front Microbiol. 2019 ;10 1273
    Liu Y, Yi L, Ruan C, Yao S, Deng L, Zeng K.
      Utilizing antagonistic yeasts is a promising approach for managing postharvest decay of fruits. However, it is well established that various severe stresses encountered in the environment and production process cause the intracellular reactive oxygen species (ROS) accumulation in yeast cells, resulting in cell damage and loss of vitality. Here, proline has been shown to function as a cell protectant and inducer of biofilm formation able to increase the oxidative stress tolerance and the biocontrol ability of the antagonistic yeast Metschnikowia citriensis. Addition of proline to M. citriensis cells induced a significant rise in superoxide dismutase (SOD) and catalase (CAT) activity in the early and late stages of oxidative stress, respectively, and increased the maroon pigment production that directly reduced intracellular iron content and indirectly diminished intracellular ROS levels and thus inhibited ROS- and iron-induced apoptosis. Treating cells with iron chelator tropolone yielded similar results. Pigment production induced by proline also enhanced the capability of biofilm formation of M. citriensis. These results suggested an important role for pigment of M. citriensis in response to oxidative stress. The abilities of proline to scavenge intracellular ROS and inhibit apoptosis, increase pigment production, and promote biofilm formation contribute to the improvements in oxidative stress tolerance and biocontrol efficacy of M. citriensis.
    Keywords:  Metschnikowia citriensis; apoptosis; biofilm formation; intracellular iron content; maroon pigment; proline
    DOI:  https://doi.org/10.3389/fmicb.2019.01273
  11. Apoptosis. 2019 Jun 26.
    Mohammad J, Singh RR, Riggle C, Haugrud B, Abdalla MY, Reindl KM.
      Piperlongumine (PL) is an alkaloid that inhibits glutathione S-transferase pi 1 (GSTP1) activity, resulting in elevated reactive oxygen species (ROS) levels and cancer-selective cell death. We aimed to identify stress-associated molecular responses to PL treatment in pancreatic ductal adenocarcinoma (PDAC) cells. GSTP1 directly interacts with JNK, which is activated by oxidative stress and can lead to decreased cancer cell proliferation and cell death. Therefore, we hypothesized that JNK pathways are activated in response to PL treatment. Our results show PL causes dissociation of GSTP1 from JNK; robust JNK, c-Jun, and early ERK activation followed by suppression; increased expression of cleaved caspase-3 and cleaved PARP; and nuclear translocation of Nrf2 and c-Myc in PDAC cells. Gene expression analysis revealed PL caused a > 20-fold induction of heme oxygenase-1 (HO-1), which we hypothesized was a survival mechanism for PDAC cells under enhanced oxidative stress. HO-1 knockout resulted in enhanced PL-induced PDAC cell death under hypoxic conditions. Similarly, high concentrations of the HO-1 inhibitor, ZnPP (10 µM), sensitized PDAC cells to PL; however, lower concentrations ZnPP (10 nM) and high or low concentrations of SnPP both protected PDAC cells from PL-induced cell death. Interestingly, the JNK inhibitor significantly blocked PL-induced PDAC cell death, Nrf-2 nuclear translocation, and HMOX-1 mRNA expression. Collectively, the results demonstrate JNK signaling contributes to PL-induced PDAC cell death, and at the same time, activates Nrf-2 transcription of HMOX-1 as a compensatory survival mechanism. These results suggest that elevating oxidative stress (using PL) while at the same time impairing antioxidant capacity (inhibiting HO-1) may be an effective therapeutic approach for PDAC.
    Keywords:  Apoptosis; GSTP1 inhibitor; Nrf2; Oxidative stress; SnPP; ZnPP
    DOI:  https://doi.org/10.1007/s10495-019-01553-9
  12. Front Immunol. 2019 ;10 1252
    Wang Y, Wang Y, Wu J, Liu C, Zhou Y, Mi L, Zhang Y, Wang W.
      Neutrophil extracellular traps (NETs) are one of the most powerful and specific tools for neutrophils to clean up extracellular microbes, but the mechanisms of NETosis under infection are scarcely studied. In this study, by examining the neutrophils from human peripheral blood and mouse abdomen, we demonstrated that PRAK dysfunction resulted in a significantly reduced NET formation and elevated apoptotic cells. Furthermore, PRAK dysfunction could lead to impaired NET-mediated antibacterial activity and shorten the survival of mice with CLP-induced sepsis. Mechanism studies revealed that attenuated NET formation in PRAK dysfunctional neutrophils correlated with overproduction of reactive oxygen species (ROS), which triggered apoptosis through excessive autophagy. The imbalance of NET formation and apoptosis was further regulated by treatment with lower ROS in hypoxia. Here, we propose a novel candidate, PRAK, which can sense the oxidative stress and regulate the releasing of ROS, may be the master molecular switch to regulate the NETosis-apoptosis axis of neutrophils.
    Keywords:  PRAK; apoptosis; autophagy; neutrophil extracellular traps (NETs); reactive oxygen species (ROS)
    DOI:  https://doi.org/10.3389/fimmu.2019.01252
  13. Crit Rev Food Sci Nutr. 2019 Jun 24. 1-13
    Qi X, Zhang Y, Guo H, Hai Y, Luo Y, Yue T.
      Excess oral iron in the intestinal tract usually produces reactive oxygen species via Fenton and Haber-Weiss reaction, so oxidative stress is triggered. Lipid peroxidation procedurally appears, ferroptosis, apoptosis and necrosis are often induced, subsequently, mitochondrial damage, endoplasmic reticulum dysfunction and even cell death occur. As a result, the intestinal epithelial cells are destroyed, leading to the incompleteness of intestinal mechanical barrier. Simultaneously, iron supplement can change the compositions and metabolic processes of intestinal microbes, and the intestinal inflammatory may be worsened. In principle, the easier dissociation of Fe2+ from oral iron supplements is, the more serious intestinal inflammation will occur. Fortunately, some interventions have been developed to alleviate these side effects. For instance, some antioxidants e.g. VE and ferulic acid have been used to prevent the formation of free radicals or to neutralize the formed free radicals. Furthermore, some new iron supplements with the ability of slow-releasing Fe2+, e.g. ferrous citrate liposome and EDTA iron sodium, have been successfully prepared. In order to recover the intestinal micro-ecological balance, probiotics and prebiotics, bacterial consortium transplantation, and fecal microbiota transplantation have been developed. This study is meaningful for us to develop safer oral iron supplements and to maintain intestinal micro-ecological health.
    Keywords:  Intestinal barrier; Intestinal inflammation; Oral iron; Oxidative stress; Side effects
    DOI:  https://doi.org/10.1080/10408398.2019.1630599
  14. Toxicology. 2019 Jun 20. pii: S0300-483X(19)30179-9. [Epub ahead of print]
    Chen X, Zhang Y, Jiang S, Huang S.
      Our previous work has shown that maduramicin, an effective coccidiostat used in the poultry production, executed its toxicity by inducing apoptosis of skeletal myoblasts. However, the underlying mechanism is not well understood. Here we show that maduramicin induced apoptosis of skeletal muscle cells by activating c-Jun N-terminal kinase (JNK) pathway in murine C2C12 and L6 myoblasts as well as skeletal muscle tissue. This is supported by the findings that inhibition of JNK with SP600125 or ectopic expression of dominant negative c-Jun attenuated maduramicin-induced apoptosis in C2C12 cells. Furthermore, we found that treatment with maduramicin reduced the cellular protein level of protein phosphatase 5 (PP5). Overexpression of PP5 substantially mitigated maduramicin-activated JNK and apoptosis. Moreover, we noticed that treatment with maduramicin elevated intracellular reactive oxygen species (ROS) level. Pretreatment with N-acetyl-L-cysteine (NAC), a ROS scavenger and antioxidant, suppressed maduramicin-induced inhibition of PP5 and activation of JNK as well as apoptosis. The results indicate that maduramicin induction of ROS inhibits PP5, which results in activation of JNK cascade, leading to apoptosis of skeletal muscle cells. Our finding suggests that manipulation of ROS-PP5-JNK pathway may be a potential approach to prevent maduramicin-induced apoptotic cell death in skeletal muscle.
    Keywords:  Apoptosis; Maduramicin; Protein phosphatase 5; Reactive oxygen species; Skeletal muscle; c-Jun N-terminal kinase
    DOI:  https://doi.org/10.1016/j.tox.2019.152239
  15. NPJ Precis Oncol. 2019 ;3 16
    Kshattry S, Saha A, Gries P, Tiziani S, Stone E, Georgiou G, DiGiovanni J.
      Perturbing redox homeostasis potentially constitutes a selective cancer-killing strategy. An engineered human enzyme, cyst(e)inase that degrades extracellular cysteine (l-Cys) and cystine (CSSC) leading to depletion of intracellular l-Cys and glutathione (GSH) was evaluated for its effects on pancreatic cancer cell lines. Cyst(e)inase caused oxidative stress and apoptosis in only Panc1 cells, whereas MIA-PaCa2 and BxPC3 cells demonstrated survival under conditions of cyst(e)inase-mediated l-Cys depletion through maintenance of mitochondrial metabolism and lower levels of reactive oxygen species (ROS). A correlation was also observed between thioredoxin 1 protein levels and resistance to cyst(e)inase treatment. Notably, cyst(e)inase in combination with auranofin, a thioredoxin reductase inhibitor, caused a synergistic increase in mitochondrial ROS and apoptosis and inhibition of mitophagy in the more resistant cells. In addition, auranofin treatment sensitized the more resistant pancreatic cancer xenografts to cyst(e)inase without systemic toxicity. These data provide strong rationale to further investigate therapeutic strategies that target multiple antioxidant pathways for treatment of pancreatic ductal adenocarcinoma.
    Keywords:  Biologics; Cancer therapy; Pancreatic cancer
    DOI:  https://doi.org/10.1038/s41698-019-0088-z
  16. Toxicol Ind Health. 2019 Jun;35(6): 445-456
    Azari MR, Mohammadian Y, Peirovi H, Omidi M, Khodagholi F, Pourahmad J, Mehrabi Y, Rafieepour A.
      In theenvironment, co-exposure to short-multiwalled carbon nanotubes (S-MWCNTs) and polycyclic aromatic compounds (PAHs) has been reported. In the co-exposure condition, the adsorption of PAHs onto MWCNTs may reduce PAHs toxic effect. The objective of this study was to investigate the cytotoxicity of S-MWCNTs and benzo[a]pyrene (B[a]P) individually, and in combination in human lung cell lines (A549). The adsorption of B[a]P onto MWCNTs was measured spectrometrically. In vitro toxicity was assessed through cell viability, reactive oxygen species (ROS) generation, apoptosis, and 8-hydroxy-2'-deoxyguanosine (8-OHdG) generation experiments. The S-MWCNTs demonstrated cytotoxicity through the generation of ROS, apoptosis, and 8-OHdG in A549 cells. Co-exposure to S-MWCNTs and B[a]P demonstrated a significant reduction in ROS generation and apoptosis compared with the sum of their separate toxic effects at the same concentrations. Decreasing the bioavailability of B[a]P by MWCNT interaction is the probable reason for the antagonistic effects of the co-exposure condition. The findings of this study will contribute to a better understanding of the health effects of co-exposures to air pollutants and could be a starting point for modifying future health risk assessments.
    Keywords:  Short-multiwalled carbon nanotubes; antagonistic effect; benzo[a]pyrene; co-exposure; lung cells
    DOI:  https://doi.org/10.1177/0748233719854570
  17. Behav Brain Res. 2019 Jun 20. pii: S0166-4328(19)30365-1. [Epub ahead of print] 112049
    Park SS, Park HS, Kim CJ, Baek SS, Kim TW.
      Loss of the mother-infant relationship during early childhood affects infant development and is known to increase the infant's vulnerability to neuropsychiatric disorders throughout life. Serotonin deficits and mitochondrial dysfunction in the dorsal raphe may underlie mood disorders such as anxiety and depression. Exercise is known to have a positive effect on brain function. In this study, we investigated the effect of exercise on mitochondrial function, apoptosis, and serotonin levels in the dorsal raphe as well as behavioral changes in cases of maternal separation. Exposure to the stress of maternal separation resulted in mitochondrial dysfunction in the dorsal raphe, including impaired Ca2+ homeostasis, an increase in reactive oxygen species such as H2O2, and a decrease in the O2 respiration rate. Exposure to maternal separation stress also decreased tryptophan hydroxylase and 5-hydroxytryptamine positive cells and increased apoptosis, anxiety, and depression. The impairments in mitochondrial function, apoptosis, and serotonin in the dorsal raphe, as well as anxiety and depression, were all improved by exercise. Exercise might alter mitochondrial function, serotonin levels, and the rate of apoptosis in the dorsal raphe. Therefore, exercise might be an important non-pharmacological intervention for the prevention and treatment of the adverse effects of maternal separation.
    Keywords:  apoptosis; dorsal raphe; exercise; maternal separation; mitochondria; mood disorder
    DOI:  https://doi.org/10.1016/j.bbr.2019.112049
  18. Epigenetics. 2019 Jun 24.
    Lv S, Wen H, Shan X, Li J, Wu Y, Yu X, Huang W, Wei Q.
      Histone methyltransferase KMT2D has diverse functions and distinct mechanisms in different cancers. Although we have previously found KMT2D serves as an oncogene that promotes tumor growth and metastasis in prostate cancer (PCa), the functions and mechanisms of KMT2D are complicated and most remain undefined. Here, the function of KMT2D regarding DNA damage in PCa and the underlying mechanisms of KMT2D in epigenetic regulation were explored in a series of studies. Knockdown of KMT2D sensitized cells to DNA damage through the disturbance of antioxidative gene expression and increased levels of intracellular reactive oxygen species, which led to cell apoptosis and senescence. The loss of KMT2D reduced the abundance of enhancer activity markers H3K4me1 and H3K27ac, which blocked the DNA binding of FOXO3, a critical mediator of the cellular response to oxidative stress, and suppressed antioxidative gene transcription. Moreover, KMT2D deletion in PCa cells also increased their sensitivity to genotoxic anticancer drugs and a PARP inhibitor, which suggested that lower levels of KMT2D may mediate the response of PCa to particular treatments. These findings further highlighted the important role of KMT2D in PCa progression and suggested that targeting KMT2D might be therapeutically beneficial for advanced PCa treatment.
    Keywords:  DNA damage; forkhead box O3; histone lysine methyltransferase 2D; histone methyltransferase; prostate cancer; reactive oxygen species
    DOI:  https://doi.org/10.1080/15592294.2019.1634985
  19. Apoptosis. 2019 Jun 25.
    Zhou W, Niu YJ, Nie ZW, Kim YH, Shin KT, Guo J, Cui XS.
      Fipronil (FPN) is a widely used phenylpyrazole pesticide that can kill pests by blocking γ-aminobutyric acid (GABA)-gated chloride channels. In addition, there are lack of studies on the effects of FPN on the female mammalian gametes. In this study, porcine oocytes were used to investigate the effects of FPN on the oocyte maturation process. The results showed that the first polar body extrusion rate significantly decreased (100 μM FPN vs. control, 18.64 ± 2.95% vs. 74.90 ± 1.50%, respectively), and oocytes were arrested at the germinal vesicle stage in 100 μM FPN group. Meanwhile, the FPN caused a significant increase in reactive oxygen species (ROS) levels and severe DNA damage inside the oocytes. Furthermore, apoptosis was enhanced along with decreases in mitochondrial membrane potential, BCL-xL, and the release of cytochrome C in FPN-treated group. Additionally, low CDK1 activity and delayed cyclin B1 degradation during germinal vesicle breakdown were found in the FPN-treated group, which resulted from the activation of ATM-P53-P21 pathway. In conclusion, FPN induces apoptosis and cell cycle arrest in porcine oocyte maturation because of increased ROS levels and DNA damage. This suggests that the FPN in the environment may have potential detrimental effects on the female mammalian reproductive system.
    Keywords:  Apoptosis; Fipronil; MPF; Oocyte maturation; Porcine
    DOI:  https://doi.org/10.1007/s10495-019-01552-w
  20. Int J Mol Sci. 2019 Jun 25. pii: E3110. [Epub ahead of print]20(12):
    Migliaccio V, Sica R, Di Gregorio I, Putti R, Lionetti L.
      High-fat diets rich in fish oil (HFO diet, mainly ω3-PUFAs), in contrast to high-fat diets rich in lard (HL diet, mainly saturated fatty acids) have been shown to induce improvement in mitochondrial function and fusion processes associated with a reduction in reactive oxygen species production in both liver and skeletal muscle. High-fat diets may also impair testicular function, and mitochondria represent important cellular organelles with a pivotal role in reproductive function. Mitochondria are dynamic organelles that frequently undergo fission/fusion processes. A shift toward mitochondrial fusion process has been associated with improvement of mitochondrial function, as well as with ω3-PUFAs protective effects. The present study aimed to analyze the effect of chronic overfeeding (six weeks) with HFO or HL diet on testicular tissue histology, oxidative stress, antioxidant defenses, and mitochondrial fusion (mitofusin 2) and fission (dynamic related protein 1) protein. Our results showed that HFO diet induced less testicular histology impairment, oxidative stress, and apoptosis compared to a HL diet. This finding was associated with an increase in antioxidant activities and a shift toward mitochondrial fusion processes induced by HFO diet compared to HL diet, suggesting that ω3-PUFAs may act as bioactive compound targeting mitochondria dynamics to prevent testicular impairment.
    Keywords:  DRP1; MFN2; apoptosis; oxidative stress; testis; ω3 polyunsaturated fatty acids
    DOI:  https://doi.org/10.3390/ijms20123110
  21. Environ Sci Pollut Res Int. 2019 Jun 25.
    Liu X, Chen Q, Ali N, Zhang J, Wang M, Wang Z.
      The biotoxicity of heavy metals in sediments toward benthic organisms has evoked great concern for the health of freshwater ecosystems. This study applied a sediment toxicity testing protocol to investigate the single and joint toxicity of cadmium (Cd) and lead (Pb) on Bellamya aeruginosa. B. aeruginosa were exposed to different concentrations of Cd (5, 25, and 100 mg/kg), Pb (20, 100, and 400 mg/kg), and their different concentration combinations. A suite of biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), metallothionein (MT), malondialdehyde (MDA), and acetylcholinesterase (AChE), were measured after 7, 14, 21, and 28 days of exposure to evaluate their oxidative stress status. Cell apoptosis of soft tissue was also determined after exposure. Results revealed that these endpoints represented sensitive biomarkers for the characterization of the oxidative stress response induced by these metals. Specifically, a decrease of SOD and GPx and an increase of MDA were indicative of the potential failure of the antioxidant defense system in neutralizing the reactive oxygen species (ROS) generated in the exposure of the Pb-treated group. The integrated biomarker response (IBR) index revealed the most significant sub-lethal toxicity for Pb-spiked sediments, leading to the highest rate of cell apoptosis (70.8%). Exposure to Cd resulted in a time- and dose-dependent effect on MT levels, which suggested active detoxification of this metal. Exposure to the mixture resulted in amelioration of Pb toxicity, likely due to the competitive binding of Cd to active enzyme, with the result of an observed antagonistic interaction. This study indicated that B. aeruginosa represents a good biomonitor for assessing Cd and Pb contamination of sediments, and laid the foundation for their potential risk assessments in freshwater ecosystems.
    Keywords:  Bellamya aeruginosa; Biomarkers; Cadmium; Lead; Oxidative stress; Sediment toxicity
    DOI:  https://doi.org/10.1007/s11356-019-05769-9
  22. Food Chem Toxicol. 2019 Jun 19. pii: S0278-6915(19)30389-8. [Epub ahead of print] 110600
    Chen Y, Li C, Song P, Yan B, Yang X, Wu Y, Ma P.
      Diisononyl phthalate (DIDP) is commonly used as a plasticizer in industrial and consumer products, however, its toxicity remains unclear. This study investigated the possible involvement of oxidative stress in DIDP-induced liver and kidney toxicity. Liver function and kidney function, tissue lesions, oxidative stress biomarkers, inflammatory mediators and apoptosis factors were investigated in this study. The results showed that oral exposure to DIDP induced a marked increase in lever of alanine aminotransferase (ALT), aspartate aminotransferase (AST), urinary nitrogen (UREA) and creatinine (CREA), decrease in albumin (ALB) level, as well as causing hepatic and renal histopathological change. Investigation of the role of oxidative stress pathways showed that DBP exposure could lead to a significant increase in levels of reactive oxygen species (ROS), malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and nuclear factor-κB (NF-κB), while a decrease in glutathione (GSH) levels were observed. Administration of vitamin E to DIDP-treated mice restored these biochemical parameters to within normal levels, and resulted in less damage to livers and kidneys. Overall, these results suggest that the oxidative stress pathway is involved in DIDP-induced toxicity.
    Keywords:  Diisononyl phthalate; Hepatic; Oxidative stress; Renal
    DOI:  https://doi.org/10.1016/j.fct.2019.110600
  23. Naunyn Schmiedebergs Arch Pharmacol. 2019 Jun 24.
    Shibani F, Sahamsizadeh A, Fatemi I, Allahtavakoli M, Hasanshahi J, Rahmani M, Azin M, Hassanipour M, Mozafari N, Kaeidi A.
      Oleuropein, as an olive leaf extract antioxidant polyphenol, has been reported to be a free radical scavenger. This study was done to investigate the effects of oleuropein, against morphine-induced hippocampus neurotoxicity and memory impairment in rats. The Morris water maze (MWM) test was used to assess the effect of oleuropein (5, 15, and 30 mg/kg, i.p., co-administrated with morphine) on spatial learning and memory of male Wistar rats which were treated with morphine sulfate (45 mg/kg, s.c., 4 weeks). In order to evaluate the cleaved caspase-3, Bax, and Bcl2 protein expression (as biochemical markers of apoptosis) in CA1 area of hippocampus tissue, the western blot test was used. Also, to evaluate the oxidative stress status of hippocampus CA1 area tissue, the malondialdehyde (MDA) level, superoxide dismutase (SOD) activity, and glutathione peroxidase (GPx) activity were assessed. The data showed that oleuropein treatment (15 and 30 mg/kg) improves the spatial learning and memory impairments in morphine-treated animals. Also, oleuropein treatment decreased the apoptosis and oxidative stress levels in the hippocampus CA1 area of morphine-treated rats. Oleuropein can prevent the spatial learning and memory impairments in morphine-treated rats. Molecular mechanisms underlying the observed effects could be at least partially related to the inhibition of neuronal apoptosis and oxidative stress in the hippocampus CA1 area of morphine-treated rats.
    Keywords:  Apoptosis; Hippocampus; Learning and memory; Morphine; Oleuropein; Oxidative stress
    DOI:  https://doi.org/10.1007/s00210-019-01678-3
  24. Theranostics. 2019 ;9(11): 3293-3307
    Zhu T, Shi L, Yu C, Dong Y, Qiu F, Shen L, Qian Q, Zhou G, Zhu X.
      The noninvasive nature of photodynamic therapy (PDT) enables the preservation of organ function in cancer patients. However, PDT is impeded by hypoxia in the tumor microenvironment (TME) caused by high intracellular oxygen (O2) consumption and distorted tumor blood vessels. Therefore, increasing oxygen generation in the TME would be a promising methodology for enhancing PDT. Herein, we proposed a concept of ferroptosis-promoted PDT based on the biochemical characteristics of cellular ferroptosis, which improved the PDT efficacy significantly by producing reactive oxygen species (ROS) and supplying O2 sustainably through the Fenton reaction. In contrast to traditional strategies that increase O2 based on decomposition of limited concentration of hydrogen peroxide (H2O2), our methodology could maintain the concentration of H2O2 and O2 through the Fenton reaction. Methods: For its association with sensitivity to ferroptosis, solute carrier family 7 member 11 (SLC7A11) expression was characterized by bioinformatics analysis and immunohistochemistry of oral tongue squamous cell carcinoma (OTSCC) specimens. Afterwards, the photosensitizer chlorin e6 (Ce6) and the ferroptosis inducer erastin were self-assembled into a novel supramolecular Ce6-erastin nanodrug through hydrogen bonding and π-π stacking. Then, the obtained Ce6-erastin was extensively characterized and its anti-tumor efficacy towards OTSCC was evaluated both in vitro and in vivo. Results: SLC7A11 expression is found to be upregulated in OTSCC, which is a potential target for ferroptosis-mediated OTSCC treatment. Ce6-erastin nanoparticles exhibited low cytotoxicity to normal tissues. More significantly, The over-accumulated intracellular ROS, increased O2 concentration and inhibited SLC7A11 expression lead to enhanced toxicity to CAL-27 cells and satisfactory antitumor effects to xenograft tumour mouse model upon irradiation. Conclusion: Our ferroptosis promoted PDT approach markedly enhances anticancer actions by relieving hypoxia and promoting ROS production, thereby our work provides a new approach for overcoming hypoxia-associated resistance of PDT in cancer treatment.
    Keywords:  Fenton reaction; carrier free; ferroptosis; nanodrug; photodynamic therapy
    DOI:  https://doi.org/10.7150/thno.32867
  25. Eur J Pharmacol. 2019 Jun 20. pii: S0014-2999(19)30442-X. [Epub ahead of print] 172490
    Lin J, Fang L, Li H, Li Z, Lyu L, Wang H, Xiao J.
      Doxorubicin (DOX) is a classic anti-tumor chemotherapeutic used to treat a wide range of tumors. One major downfall of DOX treatment is it can induce fatal cardiotoxicity. Astragaloside IV (AS-IV) is one of the primary active ingredients that can be isolated from the traditional Chinese herbal medicine, Astragalus membranaceus. This study uses both in vitro and in vivo tools to investigate whether AS-IV alleviates DOX induced cardiomyopathy. We found that AS-IV supplementation alleviates body weight loss, myocardial injury, apoptosis of cardiomyocytes, cardiac fibrosis and cardiac dysfunction in DOX-treated mice. Also, DOX-induced cardiomyocyte injury and apoptosis were effectively improved by AS-IV treatment in vitro. NADPH oxidase (NOX) plays an important role in the progress of the oxidative signal transduction and DOX-induced cardiomyopathy. In this study, we found that AS-IV treatment relieves DOX-induced NOX2 and NOX4 expression and oxidative stress in cardiomyocytes. In conclusion, AS-IV, an antioxidant, attenuates DOX-induced cardiomyopathy through the suppression of NOX2 and NOX4.
    Keywords:  Astragaloside IV; Cardiotoxicity; Doxorubicin; NAPDH oxidase
    DOI:  https://doi.org/10.1016/j.ejphar.2019.172490
  26. Artif Organs. 2019 Jun 25.
    Zeng X, Wang S, Li S, Yang Y, Fang Z, Huang H, Wang Y, Fan X, Ye Q.
      Hypothermic oxygenated machine perfusion (HOPE) is a safe and reliable method that could alleviate liver injury in donation after circulatory death (DCD). This study focuses on the role of autophagy in HOPE's protective effect on DCD liver injury. A 30-min warm ischemic liver model was established in mice. After 4 h of cold storage (CS), 1 h of hypothermic machine perfusion (HMP) with 100% O2 or 100% N2 was employed. During 2 h of reperfusion, liver tissue and perfusate were collected to evaluate liver function, oxidative stress level, apoptosis, and necrosis. Western blotting was used to explore the level of autophagy. When the liver experienced warm ischemic injury, LC3B-II expression was significantly enhanced. Compared with the CS, HOPE induced lower release of AST and ALT, as well as lower oxidative stress levels, apoptosis, and necrosis cell numbers, and led to higher tissue ATP content. Meanwhile, expression of autophagy-related proteins, such as ULK1, Atg5, and LC3B-II, increased. When oxygen was completely replaced by nitrogen, the washout effect of HMP did not activate autophagy and did not relieve DCD liver injury. When the autophagy inhibitor 3-methyladenine was used in HOPE, the protective effect of HOPE was attenuated. In conclusion, DCD liver injury activated autophagy compared with healthy liver, while HOPE alleviated DCD liver injury by increasing autophagy levels further in this mouse model. However, HMP with 100% N2 had no beneficial effect on DCD liver injury or on autophagy levels compared with CS. The research on autophagy may provide a new strategy for alleviating DCD liver injury in clinical practice. This article is protected by copyright. All rights reserved.
    Keywords:  3-methyladenine; autophagy; donation after circulatory death; hypothermic deoxygenated perfusion; hypothermic oxygenated machine perfusion; warm ischemia
    DOI:  https://doi.org/10.1111/aor.13525
  27. J Cell Biochem. 2019 Jun 26.
    Yang YD, Li MM, Xu G, Zhang EL, Chen J, Sun B, Chen DW, Gao YQ.
      Mitochondrial dysfunction plays a principal role in hypoxia-induced endothelial injury, which is involved in hypoxic pulmonary hypertension and ischemic cardiovascular diseases. Recent studies have identified mitochondria-associated membranes (MAMs) that modulate mitochondrial function under a variety of pathophysiological conditions such as high-fat diet-mediated insulin resistance, hypoxia reoxygenation-induced myocardial death, and hypoxia-evoked vascular smooth muscle cell proliferation. However, the role of MAMs in hypoxia-induced endothelial injury remains unclear. To explore this further, human umbilical vein endothelial cells and human pulmonary artery endothelial cells were exposed to hypoxia (1% O2 ) for 24 hours. An increase in MAM formation was uncovered by immunoblotting and immunofluorescence. Then, we performed small interfering RNA transfection targeted to MAM constitutive proteins and explored the biological effects. Knockdown of MAM constitutive proteins attenuated hypoxia-induced elevation of mitochondrial Ca2+ and repressed mitochondrial impairment, leading to an increase in mitochondrial membrane potential and ATP production and a decline in reactive oxygen species. Then, we found that MAM disruption mitigated cell apoptosis and promoted cell survival. Next, other protective effects, such as those pertaining to the repression of inflammatory response and the promotion of NO synthesis, were investigated. With the disruption of MAMs under hypoxia, inflammatory molecule expression was repressed, and the eNOS-NO pathway was enhanced. This study demonstrates that the disruption of MAMs might be of therapeutic value for treating endothelial injury under hypoxia, suggesting a novel strategy for preventing hypoxic pulmonary hypertension and ischemic injuries.
    Keywords:  endothelial cells; hypoxia; mitochondria; mitochondria-associated membranes
    DOI:  https://doi.org/10.1002/jcb.29220
  28. J Agric Food Chem. 2019 Jun 26. 67(25): 7060-7072
    Han L, Yang Q, Li J, Cheng F, Zhang Y, Li Y, Wang M.
      As one of the main metabolites of anthocyanin, protocatechuic acid (PCA) possesses strong antioxidant activity. In the present study, we explored the capacity of PCA on the alleviation of endothelial oxidative stress and investigated the underlying mechanisms using RNA sequencing (RNA-Seq). In comparison with palmitic acid (PA)-treated cells, PCA (100 μM) significantly decreased the generations of 3-nitrotyrosine (3-NT) and 8-hydroxydeoxyguanosine (8-OHdG) (0.82 ± 0.01 vs 1.16 ± 0.05 and 0.80 ± 0.01 vs 1.48 ± 0.15, respectively, p < 0.01), two biomarkers of oxidative damage, and restored the levels of nitric oxide (NO) (0.97 ± 0.04 vs 0.54 ± 0.02, p < 0.01) and mitochondrial membrane potential (MMP) (0.96 ± 0.03 vs 0.86 ± 0.02, p < 0.01) in human umbilical vein endothelial cells (HUVECs). PCA also obviously reduced the level of reactive oxygen species (ROS) (0.86 ± 0.15 vs 2.67 ± 0.09, p < 0.01) in aorta from high-fat diet (HFD)-fed mice. RNA-Seq and Western blot analysis indicated that PCA markedly reduced the expression of cluster of differentiation 36 (CD36), a membrane fatty acid transporter, and reduced the generations of adenosine triphosphate (ATP) and acetyl coenzyme A (Ac-CoA). These effects of PCA were associated with decreased level of acetylated-lysine and restored the activity of manganese-dependent superoxide dismutase (MnSOD) through reducing the generation of Ac-CoA or activating Sirt1 and Sirt3 via a CD36/AMP-kinase (AMPK) dependent pathway.
    Keywords:  AMPK; CD36; PCA; deacetylation; endothelial oxidative stress
    DOI:  https://doi.org/10.1021/acs.jafc.9b02647
  29. Int J Biochem Cell Biol. 2019 Jun 20. pii: S1357-2725(19)30132-3. [Epub ahead of print]114 105561
    Wang X, Zhu P, Xu S, Liu Y, Jin Y, Yu S, Wei H, Li J, Zhang Q, Hasegawa T, Yao C, Yoshimura H, Wu Q, Zhao X.
      Antimony (Sb), a naturally occurring metal present in air and drinking water, has been found in the human brain, and there is evidence of its toxic effects on neurobehavioral perturbations, suggesting that Sb is a potential nerve poison. Here, we provide the first study on the molecular mechanism underlying Sb-associated neurotoxicity. Mice exposed to antimony potassium tartrate hydrate showed significantly increased neuronal apoptosis. In vitro, Sb triggered apoptosis in PC12 cells in a dose-dependent manner. Mechanically, Sb triggered autophagy as indicated by increased expression of microtubule-associated protein 1 light chain 3-II (LC3-II) and accumulation of green fluorescent protein-tagged LC3 dots. Moreover, Sb enhanced autophagic flux and sequestosome 1 (p62) degradation. Subsequent analyses showed that Sb treatment decreased phosphorylation of protein kinase B (Akt) as well as the mammalian target of rapamycin (mTOR), while an Akt activator protected PC12 cells from autophagy. Moreover, the antioxidant N-acetylcysteine attenuated Sb-induced Akt/mTOR inhibition and decreased autophagy and apoptosis, with autophagy inhibition also playing a cytoprotective role. In vivo, mice treated with Sb showed higher expression of LC3-II and p62 in the brain, consistent with the in vitro results. In summary, Sb induced autophagic cell death through reactive oxygen species-mediated inhibition of the Akt/mTOR pathway.
    Keywords:  Akt/mTOR inhibition; Antimony; Autophagy; Neuronal apoptosis; Neurotoxicity; ROS
    DOI:  https://doi.org/10.1016/j.biocel.2019.105561
  30. Food Funct. 2019 Jun 24.
    Wang H, Cheng X, Zhang L, Xu S, Zhang Q, Lu R.
      A surface-layer protein (Slp) derived from Lactobacillus acidophilus NCFM has been reported to possess multiple biological properties, including anti-inflammatory, inhibition of apoptosis in pathogen-invaded HT-29 cells and oxidative stress relief. However, its anti-tumor ability and underlying molecular mechanism are unknown. Here, we report that Slp suppresses cell proliferation and induces autophagic cell death in HCT116 cells. Accumulation of Beclin-1 and microtubule-associated protein 1 light chain 3 from II (LC3-II), and the degradation of p62 were observed when cells were treated with various concentrations of Slp (25, 50, 100 μg mL-1) for 24 h. We also found that the mammalian targets of rapamycin (mTOR) and c-Jun N-terminal kinase (JNK) signaling pathways were crucial mediators regulating Slp-induced autophagic cell death. Additionally, treatment with Slp resulted in the obvious formation of reactive oxygen species (ROS). SP600125, a JNK inhibitor, and N-acetylcysteine (NAC), a ROS inhibitor, attenuated Slp-induced autophagic cell death in HCT116 cells. Furthermore, NAC was found to prevent Slp-induced p70 and JNK phosphorylation. Taken together, our results suggest a novel mechanism of action of Slp induced autophagy, acting simultaneously through the ROS-mediated mTOR and JNK signaling pathways in HCT116 colon cancer cells.
    DOI:  https://doi.org/10.1039/c9fo00109c
  31. Int J Biol Macromol. 2019 Jun 22. pii: S0141-8130(19)31357-1. [Epub ahead of print]
    Xu WN, Yang RZ, Zheng HL, Yu W, Zheng XF, Li B, Jiang SD, Jiang LS.
      Apoptosis of annulus fibrosus (AF) is observed widely in intervertebral disc degeneration (IVDD) which causes weaken of tension in the annulus of intervertebral disc. Previous studies reported that apoptosis of AF is induced mainly by oxidative stress. SIRT2 is a major regulator of mitochondria to mediate ROS production. However, the mechanism of SIRT2 in IVDD remains unclear. Here, the expression of SIRT2 was detected in AF cells exposed to tert-Butyl hydroperoxide (TBHP) by western blotting. Autophagic flux and apoptosis were assessed by western blotting, flow cytometry and immunofluorescence respectively. Safranin O staining, HE, and immunohistochemical were used to assess the IVDD after 3, 6 and 9 months of surgical procedure in vivo. The expression of SIRT2 was decreased in AF cells treated with TBHP. Repression of mitophagy alleviated the apoptosis of AF cells caused by TBHP. Overexpression of PGC-1α prevented AF cells from apoptosis and mitophagy after applying Lenti-PGC-1α to transfect AF cells. These protections of PGC-1α were reduced by FCCP. Furthermore, the expression of PGC-1α was reduced and the level of mitophagy was increased in IVDD models. In conclusion, this study indicates that the regulation of PGC-1α expression provide a new theoretical basis for the mechanism of IVDD.
    Keywords:  Intervertebral disc degeneration; Mitophagy; PGC-1α
    DOI:  https://doi.org/10.1016/j.ijbiomac.2019.06.163
  32. Ecotoxicol Environ Saf. 2019 Jun 22. pii: S0147-6513(19)30690-6. [Epub ahead of print]182 109369
    Svobodníková L, Kummerová M, Zezulka Š, Babula P.
      Growth and developmental changes in plants induced by pharmaceuticals reflect changes in processes at the cellular and subcellular levels. Due to their growth and cellular characteristics, plant cell suspension cultures can be a suitable model for assessing toxicity. In this study, 10-1000 μg/L of the non-steroidal anti-inflammatory drug diclofenac (DCF) decreased the viability of Nicotiana tabacum BY-2 cells after 24 h of treatment. Further, 0.1-10 mg/L DCF diminished the density of the cell suspension by 9-46% after 96 h of treatment, but at 1 and 10 μg/L, DCF increased the density by 13% and 5%, respectively, after 120 h. These changes were accompanied by increased production of total reactive oxygen species (ROS) and mitochondrial superoxide (up to 17-fold and 5-fold, respectively), and a decrease in the mitochondrial membrane potential (by ∼64%) especially at 1000 μg/L DCF. The increased ROS production was accompanied by decrease in level of reactive nitrogen species (RNS; by 36%) and total thiols (by 61%). Damage to BY-2 cells was evidenced by accumulation of neutral red in acidic compartments (up to 10-fold at 1000 μg/L DCF), and increase of autophagic vacuole formation (up to 8-fold at 1000 μg/L DCF). Furthermore, irregular or stretched nuclei were observed in nearly 27% and 50% of cells at 100 and 1000 μg/L DCF, respectively. Highest levels of chromatin condensation (11% of cells) and apoptotic DNA fragmentation (7%) were found at 10 μg/L DCF. The results revealed a significant effect of DCF on BY-2 cells after 24 h of exposure. Changes in the growth and viability parameters were indisputably related to ROS and RNS production, changes in mitochondrial function, and possible activation of processes leading to cell death.
    Keywords:  Apoptosis; Cell viability; Diclofenac; Mitotic index; Oxidative stress; Tobacco BY-2
    DOI:  https://doi.org/10.1016/j.ecoenv.2019.109369
  33. Chin J Physiol. 2019 Mar-Apr;62(2):62(2): 70-79
    Chen YH, Peng SY, Cheng MT, Hsu YP, Huang ZX, Cheng WT, Wu SC.
      Glucocorticoid-induced bone loss is the most common form of secondary osteoporosis. This toxic effect has not been efficiently managed, possibly due to the incomplete understanding of the extraordinarily diverse cellular responses induced by glucocorticoid treatment. Previous literatures revealed that high dose of exogenous glucocorticoid triggers apoptosis in osteocytes and osteoblasts. This cell death is associated with glucocorticoid-induced oxidative stress. In this study, we aimed to investigate the mechanisms of glucocorticoid-induced apoptosis in osteoblasts and examine the responses of osteoclasts to the synthetic glucocorticoid, dexamethasone. We demonstrated the biphasic effects of exogenous glucocorticoid on osteoblastic mitochondrial functions and elevated intracellular oxidative stress in a dose- and time-dependent manner. On comparison, similar treatment did not induce mitochondrial dysfunctions and oxidative stress in osteoclasts. The production of reactive oxygen/nitrogen species was decreased in osteoclasts. The differences are not due to varying efficiency of cellular antioxidant system. The opposite effects on nitrogen oxide synthase might provide an explanation, as the expression levels of nos2 gene are suppressed in the osteoclast but elevated in the osteoblast. We further revealed that glucocorticoids have a substantial impact on the osteoblastic mitochondria. Basal respiration rate and ATP production were increased upon 24 h incubation of glucocorticoids. The increase in proton leak and nonmitochondrial respiration suggests a potential source of glucocorticoid-induced oxidative stress. Long-term incubation of glucocorticoids accumulates these detrimental changes and results in cytochrome C release and mitochondrial breakdown, consequently leading to apoptosis in osteoblasts. The mitochondrial alterations might be other sources of glucocorticoid-induced oxidative stress in osteoblasts.
    Keywords:  Apoptosis; glucocorticoids; osteoblasts; osteoclasts; oxidative stress
    DOI:  https://doi.org/10.4103/CJP.CJP_7_19
  34. Arch Physiol Biochem. 2019 Jun 26. 1-6
    Khaksari M, Esmaili S, Abedloo R, Khastar H.
      The aim of this study was to investigate the effects of palmatine on gentamicin toxicity. Rats arranged in four groups: 1- Sham, 2- GM, 3- & 4- GM + palmatine (50 & 100 mg/kg). Gentamicin led to increase in plasma AST, ALT, BUN and creatinine. In addition, fractional excretion of Na and K were increased and urine flow rate and creatinine clearance were decreased in gentamicin group. Liver and renal tissues malondialdehyde were increased, and glutathione was decreased in GM group. TUNEL assay showed induction of apoptosis in liver and kidney in GM group. Palmatine treatment caused reduction in plasma AST, ALT, urine flow rate, creatinine clearance, renal and hapatic malondialdehyde, apoptosis and increase in renal and hapatic glutathione, fractional excretion of Na and K, plasma BUN and creatinine in contrast to GM group. Our data showed palmatine reduced hepatotoxicity and nephrotoxicity by inhibition of oxidative stress and apoptosis.
    Keywords:  Palmatine; gentamicin; hepatotoxicity; nephrotoxicity
    DOI:  https://doi.org/10.1080/13813455.2019.1633354
  35. Redox Biol. 2019 Jun 11. pii: S2213-2317(19)30298-8. [Epub ahead of print]26 101254
    Lin Q, Li S, Jiang N, Shao X, Zhang M, Jin H, Zhang Z, Shen J, Zhou Y, Zhou W, Gu L, Lu R, Ni Z.
      Contrast-induced acute kidney injury (CI-AKI) occurs in more than 30% of patients after intravenous iodinated contrast media and causes serious complications, including renal failure and mortality. Recent research has demonstrated that routine antioxidant and alkaline therapy failed to show benefits in CI-AKI patients with high risk for renal complications. Mitophagy is a mechanism of selective autophagy, which controls mitochondrial quality and mitochondrial reactive oxygen species (ROS) through degradation of damaged mitochondria. The role of mitophagy and its regulation of apoptosis in CI-AKI are poorly understood. In this study, we demonstrated that mitophagy was induced in renal tubular epithelial cells (RTECs) during CI-AKI, both in vivo and in vitro. Meanwhile, contrast media-induced mitophagy was abolished when silencing PINK1 or PARK2 (Parkin), indicating a dominant role of the PINK1-Parkin pathway in mitophagy. Moreover, mitochondrial damage, mitochondrial ROS, RTEC apoptosis, and renal injury under contrast exposure were more severe in PINK1- or PARK2-deficient cells and mice than in wild-type groups. Functionally, PINK1-Parkin-mediated mitophagy prevented RTEC apoptosis and tissue damage in CI-AKI through reducing mitochondrial ROS and subsequent NLRP3 inflammasome activation. These results demonstrated that PINK1-Parkin-mediated mitophagy played a protective role in CI-AKI by reducing NLRP3 inflammasome activation.
    Keywords:  Acute kidney injury; Apoptosis; Contrast media; Mitochondrial ROS; Mitophagy; NLRP3 inflammasome
    DOI:  https://doi.org/10.1016/j.redox.2019.101254
  36. Reprod Domest Anim. 2019 Jun 22.
    Wang X, Zhu X, Liang X, Xu H, Liao Y, Lu K, Lu S.
      As a natural plant-derived antitoxin, resveratrol possesses several pharmacological activities. This study aimed to evaluate the effects of resveratrol addition on nuclear maturation, oocyte quality during in vitro maturation (IVM) of porcine oocytes, and subsequent early embryonic development following somatic cell nuclear transfer (SCNT). Our experiments showed that the treatment of porcine oocytes with 5 μM resveratrol during IVM resulted in the highest rate of the first polar body extrusion. Treatment of oocytes with resveratrol had no influence on cytoskeletal dynamics, whereas it significantly increased glucose uptake ability compared to the control oocytes. Oocytes matured with 5 μM resveratrol displayed significantly lower intracellular reactive oxygen species (ROS) levels and higher relative mRNA expression levels of the genes encoding such antioxidant enzymes as catalase (CAT) and superoxide dismutase 1 (SOD1). In addition, resveratrol also prevented onset and progression of programmed cell death in porcine oocytes, which was confirmed by significant upregulation of the anti-apoptotic B cell lymphoma 2 (BCL-2) gene and significant downregulation of the pro-apoptotic BCL2 associated X (BAX) gene. Furthermore, the blastocyst rates and the blastocyst cell numbers in cloned embryos derived from the oocytes that had matured in the presence of 5 μM resveratrol were significantly increased. In conclusion, supplementation of IVM medium with 5 μM resveratrol improves the quality of porcine oocytes by protecting them from oxidative damage and apoptosis, which leads to the production of meiotically matured oocytes exhibiting enhanced developmental potential following SCNT. This article is protected by copyright. All rights reserved.
    Keywords:  early embryonic development; in vitro maturation (IVM); porcine oocytes; resveratrol; somatic cell nuclear transfer (SCNT)
    DOI:  https://doi.org/10.1111/rda.13493
  37. Br J Haematol. 2019 Jun 24.
    Ma J, Liu B, Yu D, Zuo Y, Cai R, Yang J, Cheng J.
      Acute myeloid leukaemia (AML) cells possess metabolism profiles, such as higher rates of oxidative phosphorylation and dependence on fatty acid oxidation for survival, and are dependent on the sophisticated regulation of reactive oxygen species (ROS) generation for survival, drug resistance and stemness maintenance. We found that sensitivity of primary AML cells to cytarabine correlated with SOD2 acetylation and the ability of the drug to induce mitochondrial ROS. The SOD2 deacetylase, SIRT3, protected AML cells from chemotherapy as shown by inhibited apoptosis via inhibited drug-induced production of mitochondrial ROS. SIRT3 significantly decreased nicotinamide adenine dinucleotide phosphate (NADP)/reduced NADP ratio and increased reduced glutathione/oxidized glutathione ratio. Furthermore, SIRT3 enhanced oxidative phosphorylation (OxPhos) in AML cells under both basic and cytarabine-treated conditions. A xenograft mouse model showed that SIRT3 overexpressing AML cells and patient-derived xenograft mice bearing high SIRT3 deacetylase activity were more resistant to chemotherapy in vivo. SIRT3 inhibitor displayed synergy with cytarabine to ablate AML cells in vitro and in mouse models. Taken together, our study showed that SIRT3 is capable of reprograming mitochondrial metabolism towards OxPhos and downregulating ROS generation, which contribute to the chemoresistance of AML cells. SIRT3 can be utilized as a potential therapeutic target to improve the anti-leukaemic efficacy of standard chemotherapeutic agents for AML.
    Keywords:  AML; ROS; SIRT3; SOD2 acetylation; chemoresistance
    DOI:  https://doi.org/10.1111/bjh.16044
  38. Reprod Fertil Dev. 2019 Jun 27.
    Lorenzo MS, Maruri A, Cruzans PR, Teplitz GM, Tello MF, Lombardo DM.
      Abattoir ovaries, which are the main source of oocytes for reproductive biotechnologies, arrive at the laboratory under ischaemic conditions. Reoxygenation generates reactive oxygen species (ROS) in ischaemic tissues, which could affect oocyte quality. The aim of this study was to evaluate the effect of supplementation of media with dimethylthiourea (DMTU) during the collection and washing of cumulus-oocyte complexes (COC) on ROS levels, COC apoptosis and oocyte nuclear and cytoplasmic maturation. Thus, the collection (TCM-199) and washing (TCM-199 with 10% porcine follicular fluid, sodium pyruvate and antibiotics) media were supplemented with 1 and 10mM DMTU. In the control group, the media were not supplemented with DMTU. Intracellular ROS levels decreased significantly in the DMTU-treated groups (P<0.05). Although no effects on rate of nuclear maturation were observed, DMTU significantly increased sperm penetration rates without increasing polyspermy (P<0.05). The addition of 10mM DMTU to the collection and washing media enhanced IVF efficiency. DMTU did not modify the early or late apoptosis of oocytes. Both concentrations of DMTU significantly increased viability and decreased the apoptosis of cumulus cells (P<0.05). These results suggest that the addition of 1 or 10mM of DMTU to the media during the collection and washing of porcine COCs is useful for decreasing cumulus apoptosis mediated by ROS and for optimising the IVF of porcine oocytes.
    DOI:  https://doi.org/10.1071/RD19020
  39. Andrologia. 2019 Jun 26. e13353
    Ekinci Akdemir FN, Yildirim S, Kandemir FM, Aksu EH, Guler MC, Kiziltunc Ozmen H, Kucukler S, Eser G.
      Testicular dysfunction or damage is among the critical side effects of chemotherapeutic drugs like cisplatin. This study was mapped out to assess the possible therapeutic effect of eugenol on cisplatin-induced testicular damage. In this experimental study, a single dose of cisplatin (15 mg/kg) was given intraperitoneally. After 72 hr of cisplatin injection, rats were sacrificed and testis tissues were removed. Tissues were examined by biochemical, histopathological and immunohistochemical methods. While tissue lipid peroxidation product and apoptotic marker levels increased, antioxidant enzyme activities of testis tissue were decreased in the cisplatin group. Additionally, histopathological damage was also determined in testis tissue. Contrary to all these results, the severity of damage in the tissue was reduced histopathologically owing to eugenol treatment. The lipid peroxidation decreased and antioxidant enzyme activities increased in the eugenol treatment group. It has been determined that eugenol has a therapeutic effect on oxidative stress and apoptosis against cisplatin-induced testicular damage.
    Keywords:  cisplatin; eugenol; testis; toxicity
    DOI:  https://doi.org/10.1111/and.13353
  40. Chem Biol Interact. 2019 Jun 20. pii: S0009-2797(19)30799-9. [Epub ahead of print]
    Tchouagué M, Grondin M, Glory A, Averill-Bates D.
      Hyperthermia is a promising anticancer treatment used in combination with radiotherapy and/or chemotherapy. Heat (42-45 °C) can kill cancer cells. Low doses of heat at milder temperatures (39-41 °C) induce thermotolerance, an adaptive survival response that upregulates defense molecules to protect cells against subsequent exposure to toxic stress. Although hyperthermia has proven effective in clinical trials, there is still much to learn about its cellular mechanisms. This study aims to understand the role of reactive oxygen species (ROS), antioxidants and the antioxidant transcription factor Nrf2 in cellular stress responses to mild and lethal heat shock. Mild thermotolerance (40 °C) and hyperthermia (42-43 °C) caused increased expression of the antioxidants peroxiredoxin-3 (Prx2) and Prx2, and its hyperoxidized form Prx-SO3. Cellular levels of superoxide and peroxides increased at 40 °C and 42 °C. Heat shock (42 °C)-induced increases in Prx3 and Prx-SO3 were inhibited by antioxidants (PEG-catalase, MnTBAP) and a Nrf2 shRNA. Glucose metabolism by the pentose phosphate pathway produces NADPH, which maintains the antioxidant glutathione in its reduced form, GSH. Heat shock (40°C-42 °C) increased GSH levels, expression of glucose transporter GLUT1, and enzymatic activity and expression of glucose 6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme in the pentose cycle. Heat-induced increases in GSH levels and G6PD expression were inhibited by antioxidants and Nrf2 knockdown. These results suggest that heat shock-generated ROS were involved in induction of cellular defense molecules Prxs, GSH and G6PD through Nrf2 activation. Our study sheds new light on the role of Nrf2 and antioxidants in cellular responses to heat shock at mild and lethal temperatures.
    Keywords:  Apoptosis; Glucose 6-phosphate dehydrogenase; Heat shock; Nrf2; Oxidative stress; Peroxiredoxin
    DOI:  https://doi.org/10.1016/j.cbi.2019.06.030
  41. Atherosclerosis. 2019 Jun 13. pii: S0021-9150(19)31369-3. [Epub ahead of print]287 70-80
    Devarakonda CV, Pereira FE, Smith JD, Shapiro LH, Ghosh M.
      BACKGROUND AND AIMS: Atherosclerosis is an inflammatory cardiovascular disorder characterized by accumulation of lipid-loaded macrophages in the intima. Prolonged accumulation leads to apoptosis of macrophages and eventually to progression of lesion development. Prevention of macrophage accumulation within the intima has been shown to reduce lesion formation. Since CD13 mediates trafficking of macrophages to sites of injury and repair, we tested the role of CD13 in atherosclerosis.METHODS: CD13+/+Ldlr-/- and CD13-/-Ldlr-/- (low density lipoprotein receptor) mice were fed basal or high fat diet (HFD) for 9, 12 and 15 weeks. Mice were euthanized and aortic roots along with innominate arteries were analyzed for atherosclerotic lesions. Cellular mechanisms were determined in vitro using CD13+/+ and CD13-/- bone marrow derived macrophages (BMDMs) incubated with highly oxidized low-density lipoprotein (oxLDL).
    RESULTS: At the 9 and 12 week time points, no differences were observed in the average lesion size, but at the 15 week time point, CD13-/-Ldlr-/- mice had larger lesions with exaggerated necrotic areas. CD13+/+ and CD13-/- macrophages endocytosed similar amounts of oxLDL, but CD13-/- macrophages generated higher amounts of oxidative stressors in comparison to CD13+/+ macrophages. This increased oxidative stress was due to increased nitric oxide production in oxLDL treated CD13-/- macrophages. Accumulated oxidative stress subsequently led to accelerated apoptosis and enhanced necrosis of oxLDL treated CD13-/- macrophages.
    CONCLUSIONS: Contrary to our prediction, CD13 deficiency led to larger atherosclerotic lesions with increased areas of necrosis. Mechanistically, CD13 deficiency led to increased nitric oxide production and consequently, greater oxidative stress.
    Keywords:  ANPEP; Atherosclerosis; CD13; L-NMMA; Macrophages; NAC; Nitric oxide; Oxidative stress; Reactive nitrogen species; Reactive oxygen species; oxLDL
    DOI:  https://doi.org/10.1016/j.atherosclerosis.2019.06.901
  42. J Cell Physiol. 2019 Jun 25.
    Li L, Chen Q, Yu Y, Chen H, Lu M, Huang Y, Li P, Chang H.
      Accumulated evidence suggested the importance of the Rho/Rho-kinase (ROCK) signaling pathway in cancer proliferation and invasion. However, its role in colorectal carcinoma (CRC) is not well understood. This study evaluated the effect of ROCK signaling pathway on CRC behavior on the basis of a novel Rho/ROCK inhibitor RKI-1447. Here, we found RKI-1447 could drastically suppress HCT-8 and HCT-116 cell growth and promoted apoptosis. Our in vitro data indicated suppressed cytoskeletal dynamics induced by RKI-1447 inhibition on mitochondrial respiration, which was evidenced by basal and maximal respiration rates, and ATP production. Simultaneously, cellular basal and maximal glycolytic rates, and glycolytic capacity were also reduced in response to RKI-1447. Moreover, RKI-1447 caused excessive reactive oxygen species generation and membrane depolarization as well as activated ER-stress. We also demonstrated CHOP is essential for RKI-1447 induced cell apoptosis. Finally, we proved inhibition of ROCK by RKI-1447 could effectively inhibit CRC growth in vivo. Taken together, this study demonstrated that inhibition of ROCK signaling pathway by RKI-1447 could suppress CRC via cytoskeleton associated mitochondrial dysfunction and cellular bioenergetics disruption. Our data suggest RKI-1447 may be an attractive antitumor drug candidate for the treatment of CRC.
    Keywords:  ER-stress; RKI-1447; cellular bioenergetics; colorectal carcinoma; mitochondrial dysfunction
    DOI:  https://doi.org/10.1002/jcp.28965
  43. Int J Nanomedicine. 2019 ;14 3753-3771
    Khan MW, Zhao P, Khan A, Raza F, Raza SM, Sarfraz M, Chen Y, Li M, Yang T, Ma X, Xiang G.
      Background: Cisplatin (CDDP), a widely used chemotherapeutic agent against hepatocellular carcinoma (HCC), faces severe resistance and hepatotoxicity problems which can be alleviated through combination therapy. Purpose: The objective of this study was to develop a pH-dependent calcium carbonate nano-delivery system for the combination therapy of CDDP with oleanolic acid (OA). Methods: A microemulsion method was employed to generate lipid coated cisplatin/oleanolic acid calcium carbonate nanoparticles (CDDP/OA-LCC NPs), and the loading concentration of CDDP and OA was measured by atomic absorption spectroscopy and HPLC respectively.Transmission electron microscopy (TEM) was used to examine the nanoparticles morphology while its pH dependent release characteristics were investigated through in vitro release study. Cellular uptake was examined through a fluorescence microscopy. Apoptotic assays and western blot analysis were conducted to explore the synergistic apoptotic effect of OA on CDDP against HCC cells. The hepatoprotective of OA for CDDP was evaluated through H&E staining. Results: TEM analysis revealed nanoparticles spherical shape with an average particle size of 206±15 nm, and the overall entrapment efficiency was 63.70%±3.9%. In vitro drug release study confirmed the pH-dependent property of the formulation, with the maximum CDDP release of 70%±4.6% at pH 5.5, in contrast to 28%±4.1% CDDP release at pH 7.4. Annexin V-FITC/PI assay and cell cycle analysis confirmed that CDDP and OA synergistically promoted greater HepG2 cells apoptosis for the CDDP/OA-LCC NPs as compared to their individual free drug solutions and NPs-treated groups. Western blot analysis also proved that CDDP/OA-LCC NPs induced the apoptosis by enhancing the proapoptotic protein expressions through downregulating P13K/AKT/mTOR pathway and upregulating p53 proapoptotic pathway. OA helped CDDP to overcome the resistance by downregulating the expression of proteins like XIAP, Bcl-2 via NF-κB pathway. OA also significantly alleviated CDDP-induced hepatotoxicity as evident from the decreased alanine transaminase, aspartate transaminase levels and histochemical evaluation. The possible mechanism may be related to the Nrf-2 induction via its antioxidant mechanism to maintain the redox balance and reduction in CYP2E1 activity which can lead to ROS-mediated oxidative stress. Conclusion: These results suggest that CDDP/OA-LCC NPs have promising applications for co-delivering CDDP and OA to synergize their anti-tumor activity against HCC and to utilize OA's protective effect against CDDP-induced hepatotoxicity.
    Keywords:  cisplatin; combination therapy; hepatocellular carcinoma; hepatotoxicity; oleanolic acid
    DOI:  https://doi.org/10.2147/IJN.S196651
  44. Cell Signal. 2019 Jun 21. pii: S0898-6568(19)30144-5. [Epub ahead of print] 109348
    Kong T, Qiu K, Liu M, Cheng B, Pan Y, Yang C, Chen J, Wang C.
      The neuropeptide orexin-A (OXA) has a neuroprotective effect, acting as an anti-apoptotic factor in response to multiple stimuli. Apoptosis induced by endoplasmic reticulum stress (ERS) underlies oxygen-glucose deprivation and reoxygenation (OGD/R)-induced cell damage, an in vitro model of ischemia/reperfusion injury. However, that OXA inhibits ERS-induced apoptosis in the OGD/R model has not been reported. In the present study, we investigated the neuroprotective effect of OXA (0.1 μM) on OGD/R-induced damage in the human neuroblastoma cell line SH-SY5Y. After OXA treatment following 4 h oxygen-glucose deprivation (OGD) and then 4 h reoxygenation (R), cell morphology, viability, and apoptosis were analyzed by histology, Cell Counting Kit-8 assay, and flow cytometry, respectively. Western blotting was used to measure expression levels of ERS- and apoptosis-related proteins. To determine signaling pathways involved in OXA-mediated neuroprotection, the Gi pathway inhibitor pertussis toxin (PTX; 100 ng/mL) and PI3K inhibitor LY294002 (LY; 10 μM) were added. In addition, in order to prove the specificity of these characteristics, the OXA antagonist Suvorexant (DORA; Ki of 0.55 nM and 0.35 nM for OX1R and OX2R) was used for intervention. Our results showed that OGD/R induced cell damage, manifested as morphological changes and a significant decrease in viability. Furthermore, Western blotting detected an increase in ERS-related proteins GRP78, p-IRE1α, p-JNK, and Cleaved caspase-12, as well as apoptosis-related proteins Cleaved caspase-3 and Bax, and a decrease in the anti-apoptosis factor Bcl-2. OXA intervention alleviated the degree of cellular damage, and protein expression was also reversed. In addition, the protective effect of OXA was reduced by adding PTX and LY. Meanwhile, after the use of DORA, changes in the expression of related proteins were detected, and it was found that the protective effect of OXA was weakened. Collectively, our results indicate that OXA has a neuroprotective effect on OGD/R-induced cell damage by inhibiting ERS-induced apoptosis through the combined action of Gi and PI3K signaling pathways. These findings help to clarify the mechanism underlying the neuroprotective action of OXA, which should aid the development of further candidate drugs, and provide a new therapeutic direction for the treatment of ischemic stroke.
    Keywords:  Apoptosis; Endoplasmic reticulum stress (ERS); Neuroprotection; Orexin-A (OXA); Oxygen-glucose deprivation and reoxygenation (OGD/R)
    DOI:  https://doi.org/10.1016/j.cellsig.2019.109348
  45. Behav Brain Res. 2019 Jun 22. pii: S0166-4328(18)31303-2. [Epub ahead of print] 112007
    Xu B, Zhu L, Chu J, Ma Z, Fu Q, Wei W, Deng X, Ma S.
      Mitochondrial dynamics regulate mitochondrial autophagy (mitophagy) and apoptosis, which are important events for the quality control of mitochondria and mitochondrial-associated diseases. Esculetin (ESC) is a natural coumarin that exhibits inspiring biological activities in a variety of animal models, but its neuroprotective effects on cerebral ischaemia have not been clearly elucidated. In this paper, we demonstrated the effects of ESC on transient cerebral ischaemia and reperfusion injury induced in a mouse model and examined the possible underlying mechanisms by investigating mitochondrial fragmentation-regulated mitochondrial autophagy and apoptosis. The experimental results showed that ESC treatment alleviated neurological defects and improved cognitive impairments in transient bilateral common carotid artery occlusion (tBCCAO)-treated mice. Further mechanism studies showed that tBCCAO induced mitochondrial oxidative stress injuries and triggered mitochondrial fragmentation, which were evident by the elevated levels of malondialdehyde and mitochondrial dynamin-related protein 1 (Drp1) and the downregulated activities of superoxide dismutase and nuclear transcription factor E2-related factor 2 (Nrf2). ESC treatment significantly alleviated tBCCAO-induced mitochondrial stress and mitochondrial fragmentation. Moreover, mitophagy and mitochondrial apoptosis were stimulated in response to the mitochondrial oxidative stress in the hippocampus of tBCCAO-treated mice, and ESC treatment regulated the expression of mitophagy-related factors, including Bnip3, Beclin1, Pink1, and parkin, the LC-3 II/I ratio, and apoptosis-related factors, including p53, Bax, and caspase 3. Taken together, our results suggest that ESC treatment regulated hippocampal mitophagy and mitochondrial apoptosis triggered by mitochondrial stress via the mediation of mitochondrial fragmentation during transient cerebral ischaemia and reperfusion injury, which provides insight into the potential of ESC for further therapeutic implications.
    Keywords:  Cerebral ischaemia; Esculetin; Mitochondrial fragmentation; Mitophagy
    DOI:  https://doi.org/10.1016/j.bbr.2019.112007
  46. J Assoc Res Otolaryngol. 2019 Jun 24.
    Guo S, Xu N, Chen P, Liu Y, Qi X, Liu S, Li C, Tang J.
      Gentamicin, one of the most widely used aminoglycoside antibiotics, is known to have toxic effects on the inner ear. Taken up by cochlear hair cells and spiral ganglion neurons (SGNs), gentamicin induces the accumulation of reactive oxygen species (ROS) and initiates apoptosis or programmed cell death, resulting in a permanent and irreversible hearing loss. Since the survival of SGNs is specially required for cochlear implant, new procedures that prevent SGN cell loss are crucial to the success of cochlear implantation. ROS modulates the activity of the mammalian target of rapamycin (mTOR) signaling pathway, which mediates apoptosis or autophagy in cells of different organs. However, whether mTOR signaling plays an essential role in the inner ear and whether it is involved in the ototoxic side effects of gentamicin remain unclear. In the present study, we found that gentamicin induced apoptosis and cell loss of SGNs in vivo and significantly decreased the density of SGN and outgrowth of neurites in cultured SGN explants. The phosphorylation levels of ribosomal S6 kinase and elongation factor 4E binding protein 1, two critical kinases in the mTOR complex 1 (mTORC1) signaling pathway, were modulated by gentamicin application in the cochlea. Meanwhile, rapamycin, a specific inhibitor of mTORC1, was co-applied with gentamicin to verify the role of mTOR signaling. We observed that the density of SGN and outgrowth of neurites were significantly increased by rapamycin treatment. Our finding suggests that mTORC1 is hyperactivated in the gentamicin-induced degeneration of SGNs, and rapamycin promoted SGN survival and outgrowth of neurites.
    Keywords:  gentamicin; inner ear; mammalian target of rapamycin; ototoxicity; spiral ganglion neurons
    DOI:  https://doi.org/10.1007/s10162-019-00717-3
  47. J Med Food. 2019 Jun 26.
    Demirel Sezer E, Oktay LM, Karadadaş E, Memmedov H, Selvi Gunel N, Sözmen E.
      In recent years, natural products gained popularity with their anti-inflammatory and antioxidant effects mediated by chemical compounds within their composition. Study results offering them as palliative therapy options in cancer or as anticancer agents with high levels of cytotoxicity brought a new approach to combine cancer treatment protocols with these products. From a different perspective, edible types of these products are suggested in daily diets due to their potential cancer preventive effects. Our preliminary work was on blueberry extracts (Vaccinium myrtillus) as a main representative of these natural products, and the contents of the extracts were analyzed with liquid chromatography tandem mass spectrometry (LC MS/MS) to reveal the composition and distribution of polyphenolic compounds within. The most abundant polyphenols detected in V. myrtillus extracts were quercetin, kaempferol, and a phenolic acid, gentisic acid (GA). The compounds were further evaluated on treated HCT-116 cells for their potential anticancer effects by measuring total antioxidant status, total oxidant status, and 8-hydroxydeoxyguanosine levels for evaluation of oxidative stress and through protein array analysis and flow cytometric analysis for evaluation of apoptosis. In analysis of oxidative stress parameters, reduced total oxidant levels and reduced oxidative stress index levels were found in cells treated with the compounds in comparison with untreated cells. In apoptosis-related protein profiles, at least twofold reduction in various apoptotic proteins was observed after quercetin and kaempferol treatment, whereas a different profile was observed for GA. Overall, results of this study showed that quercetin and kaempferol have strong cytotoxic, antioxidant, and apoptotic effects, although GA is mostly effective as an antioxidant polyphenol on HCT-116 cells.
    Keywords:  Gentisic Acid; HCT-116; Kaempferol; Quercetin; apoptosis; blueberry; colorectal cancer; oxidative stress
    DOI:  https://doi.org/10.1089/jmf.2019.0098
  48. Int J Mol Sci. 2019 Jun 21. pii: E3046. [Epub ahead of print]20(12):
    Dougan J, Hawsawi O, Burton LJ, Edwards G, Jones K, Zou J, Nagappan P, Wang G, Zhang Q, Danaher A, Bowen N, Hinton C, Odero-Marah VA.
      Peroxidasin (PXDN), a human homolog of Drosophila PXDN, belongs to the family of heme peroxidases and has been found to promote oxidative stress in cardiovascular tissue, however, its role in prostate cancer has not been previously elucidated. We hypothesized that PXDN promotes prostate cancer progression via regulation of metabolic and oxidative stress pathways. We analyzed PXDN expression in prostate tissue by immunohistochemistry and found increased PXDN expression with prostate cancer progression as compared to normal tissue or cells. PXDN knockdown followed by proteomic analysis revealed an increase in oxidative stress, mitochondrial dysfunction and gluconeogenesis pathways. Additionally, Liquid Chromatography with tandem mass spectrometry (LC-MS/MS)-based metabolomics confirmed that PXDN knockdown induced global reprogramming associated with increased oxidative stress and decreased nucleotide biosynthesis. We further demonstrated that PXDN knockdown led to an increase in reactive oxygen species (ROS) associated with decreased cell viability and increased apoptosis. Finally, PXDN knockdown decreased colony formation on soft agar. Overall, the data suggest that PXDN promotes progression of prostate cancer by regulating the metabolome, more specifically, by inhibiting oxidative stress leading to decreased apoptosis. Therefore, PXDN may be a biomarker associated with prostate cancer and a potential therapeutic target.
    Keywords:  PXDN; apoptosis; metabolome; oxidative stress; prostate cancer
    DOI:  https://doi.org/10.3390/ijms20123046
  49. Ecotoxicol Environ Saf. 2019 Jun 21. pii: S0147-6513(19)30686-4. [Epub ahead of print]181 548-558
    Mohamed AA, Abdellatief SA, Khater SI, Ali H, Al-Gabri NA.
      Fenpropathrin (FNP) is a member of the synthetic pyrethroids. Herein, the present study was conducted to investigate, for the first time, the potentially harmful effects of FNP on the reproductive system of male rats. In addition, the prophylactic or concurrent influence of camel milk (CM) was assessed. Adult male rats were divided into five groups; control, vehicle control (oil), CM (2ml/rat/day), FNP (15mg/kg bwt/60 days), CM/FNP (prophylaxis) and FNP /CM (co-treated) groups. Sperm morphology, count, serum testosterone (TES), luteinizing hormone (LH) and follicle-stimulating hormone (FSH), thiobarbituric acid reactive substances (TBARS), total antioxidant capacity (TAC), superoxide dismutase (SOD), testicular enzymes, and comet assay analysis were estimated. In addition, histopathology, the ultrastructure of testicular tissue and apoptosis were evaluated. Reduced body weight and gonadosomatic index were observed in the FNP exposed group. TES, LH, FSH were markedly declined following FNP treatment. SOD and TAC concentrations were reduced while PC and TBARS were significantly elevated in FNP group indicating oxidative stress. Furthermore, FNP induced DNA damage and apoptosis in the testis which was evidenced histopathologically and by electron microscope examination. CM significantly counteracted FNP reprotoxic effects, particularly at the prophylactic routine (CM/FNP) than the co-exposure (FNP/CM) one. Conclusively, these findings verified that CM could be a potential candidate therapy against FNP reprotoxic impacts.
    Keywords:  Apoptosis; Camel milk; Comet; Electron microscope; Fenpropathrin; Testicular enzymes
    DOI:  https://doi.org/10.1016/j.ecoenv.2019.06.047
  50. Front Aging Neurosci. 2019 ;11 135
    Wang Y, Zhang Y, Zhang X, Yang T, Liu C, Wang P.
      β-amyloid (Aβ) deposition, neurofibrillary tangles induced by phosphorylation of tau protein, and neuronal apoptosis are pathological hallmarks of Alzheimer's disease (AD). The dementia rate in alcoholic abusers were found to be higher than in control people. The present study explored the potential roles of alcohol dehydrogenase 1B (ADH1B) in AD pathology by determining the ADH1B levels in AD patient sera, in the hippocampus of APP/PS-1 AD model mice, and in an AD model cell line treated with Aβ1-42. The results show that ADH1B levels decreased significantly both in the serum of AD patients and in the hippocampus of APP/PS-1 AD model mice. In addition, the apoptotic rate was reduced and viability was significantly increased in AD model cells transfected with ADH1B overexpression vector. The levels of the p75 neurotrophin receptor (p75NTR), an Aβ1-42 receptor, were down-regulated in the ADH1B overexpressing AD model cell and up-regulated in cells transfected with the shRNA vector of ADH1B. Protein levels of cleaved caspase-3 and Bax decreased significantly, whereas Bcl-2 levels increased in cells overexpressing ADH1B. The opposite trend was observed for cleaved caspase-3, Bax, and Bcl-2 levels in cells transfected with the shRNA vector of ADH1B. The levels of reactive oxygen species (ROS) were found to be reduced in ADH1B overexpressing cells and increased when cells were transfected with the shRNA vector of ADH1B. These results indicate that ADH1B might be important in the prevention of AD, especially for abusers of alcohol, and a potential new target of AD treatment.
    Keywords:  Alzheimer’s disease; alcohol dehydrogenase 1B; apoptosis; p75NTR; β-amyloid
    DOI:  https://doi.org/10.3389/fnagi.2019.00135
  51. Biol Trace Elem Res. 2019 Jun 24.
    Yun S, He X, Zhang W, Chu D, Feng C.
      We aimed to evaluate the effect of grape seed proanthocyanidins (GSPCs) on neuronal apoptosis, particularly through their roles in maintaining divalent mineral element balance and resisting oxidation in rats with iron overload. A total of 40 Sprague-Dawley rats were randomly divided into control, iron overload, GSPCs, and iron overload + GSPCs groups. The iron, calcium, zinc, magnesium, and copper contents in the brain tissue of the rats were measured using inductively coupled plasma mass spectrometry. Their oxidative stress state was determined using the relevant kit. The number of apoptotic neurons was evaluated using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and synaptosome numbers were determined using the immunohistochemical approach. Fas, Bax, and Bcl-2 gene expressions in the cortex and hippocampus were detected using quantitative real-time polymerase chain reaction. After 7 weeks, compared with the control group, the zinc and magnesium contents; superoxide dismutase, glutathione peroxidase, and catalase activities; and synaptophysin and Bcl-2 gene expressions in the iron overload group were significantly decreased, whereas the iron, calcium contents, and malondialdehyde contents; TUNEL-positive cell numbers; and Fas and Bax gene expressions were significantly increased. There were no significant changes in the copper content. Conversely, the rats exhibited better recovery when GSPCs were used instead of iron alone. In summary, GSPCs protected against iron overload induced neuronal apoptosis in rats by maintaining the divalent mineral element balance, reducing oxidative stress, and regulating apoptotic genes expressions.
    Keywords:  Divalent mineral elements; Iron overload; Neuronal apoptosis; Oxidative stress; Proanthocyanidins
    DOI:  https://doi.org/10.1007/s12011-019-01766-8
  52. Toxicol In Vitro. 2019 Jun 22. pii: S0887-2333(19)30352-2. [Epub ahead of print]
    Bormio Nunes JH, de Paiva PP, Ruiz ALTG, de Carvalho JE, Corbi PP.
      Metal complexes with antitumor activities have been studied as an alternative to overcome tumor resistance to current pharmaceuticals. Recently, we described the synthesis of a silver(I) complex with 5-fluorouracil (Ag-5fu) with an effective activity in vitro against human multi-resistant ovarian tumor cells (NCI/ADR-RES) when compared to 5-fluorouracil (5fu) and cisplatin. Therefore, for a better understanding of the effect of Ag-5fu and its precursors 5fu and silver(I), the compounds were evaluated by colony formation capacity and flow cytometry assays to analyze cell cycle and cell death induction [phosphatidylserine residues (PS) exposition, multicaspases activation, production of reactive oxygen species (ROS) and mitochondrial membrane depolarization] on NCI/ADR-RES tumor cells. As observed for 5fu, Ag-5fu was able to promote G1 phase arrest and to totally inhibit colony formation. Besides, as observed to AgNO3, Ag-5fu promoted a potent PS externalization and multicaspases activation with loss of plasmatic membrane integrity. None of the compounds induced reactive oxygen species (ROS) generation. The Ag-5fu promoted mitochondrial membrane depolarization over time. The results suggest that Ag-5fu may induce regulated cell death in NCI-ADR/RES cells probably by intrinsic apoptosis. Silver(I) and 5fu play different roles on the effect of Ag-5fu in NCI/ADR-RES cells, and the activity of the Ag-5fu complex seems to be more than a simple combination of the activities of free 5fu and silver(I) ions.
    Keywords:  5-fluorouracil; Flow cytometry; Metal complex; Ovarian tumor; Silver(I)
    DOI:  https://doi.org/10.1016/j.tiv.2019.06.018
  53. Invest New Drugs. 2019 Jun 26.
    Kyriakou S, Mitsiogianni M, Mantso T, Cheung W, Todryk S, Veuger S, Pappa A, Tetard D, Panayiotidis MI.
      The anticancer activity of a series of novel synthesized, hydroxypyridone-based metal chelators (analogues of L-mimosine) was evaluated in an in vitro model of melanoma consisting of malignant melanoma (A375), non-melanoma epidermoid carcinoma (A431) and immortalized non-malignant keratinocyte (HaCaT) cells. More specifically, we have demonstrated that the L-enantiomer of a methylated analogue of L-mimosine (compound 22) can exert a potent anticancer effect in A375 cells when compared to either A431 or HaCaT cells. Moreover, we have demonstrated that this analogue has the ability to i) promote increased generation of reactive oxygen species (ROS), ii) activate both intrinsic and extrinsic apoptosis and iii) induce perturbations in cell cycle growth arrest. Our data highlights the potential of compound 22 to act as a promising therapeutic agent against an in vitro model of human malignant melanoma.
    Keywords:  Anticancer activity; L-mimosine analogues; Melanoma; Metal chelators; Skin cancer
    DOI:  https://doi.org/10.1007/s10637-019-00809-0
  54. Metabolomics. 2019 Jun 22. 15(7): 97
    Van Nguyen T, Alfaro AC.
      INTRODUCTION: Itaconic acid (ITA) has recently been identified as an antimicrobial metabolite in mammalian immune cells. The presence of ITA was also reported in different tissues of marine molluscs, indicating its role as an endogenous metabolite of molluscs. In addition, the accumulation of ITA has been observed in different tissues of mussels following pathogen challenges. However, the concentration of ITA in mussel tissues and the possible role of this metabolite in the molluscan innate immune system remain unknown.OBJECTIVES: This study aims to quantitatively measure ITA levels in different tissues of marine mussels following an experimental challenge with Vibrio sp. DO1 isolate, and to identify the antimicrobial role of ITA in the innate immune system through the measurement of metabolic and immune alterations in tissues following the challenge.
    METHODS: In this study, adult Perna canaliculus mussels were experimentally challenged with a pathogenic Vibrio sp. DO1 isolate. The metabolite profiles of five different tissues, including mantle, gill, muscle, hepatopancreas and haemolymph were obtained, and levels of ITA in each tissue were characterized using a gas chromatography-mass spectrometry (GC-MS) metabolomics approach. Flow cytometry was also employed to measure cell health parameters, including oxidative stress via reactive oxygen species (ROS) production, apoptosis via changes in mitochondrial membrane potential (MMP) and haemocyte viability.
    RESULTS: The ITA levels in mantle, gill, muscle and hepatopancreas tissues at 18-h post infection (hpi) with Vibrio sp. were 40.31, 41.71, 11.61 and 41.66 ng mg-1, respectively. In haemolymph, the level of ITA was significantly increased from 95.25 ng ml-1 at 6 hpi to 174.36 ng ml-1 at 18 hpi and 572.12 ng ml-1 at 60 hpi. In line with the accumulation of ITA, we observed increased levels of metabolites within the tricarboxylic acid (TCA) cycle, anti-inflammatory metabolites and alterations of other metabolites associated with immune responses of the host. The flow cytometry analyses revealed increases in ROS production, apoptotic cells and decreases in cell viability.
    CONCLUSIONS: We reported on the production of ITA in different tissues of P. canaliculus mussels challenged with a marine pathogen which confirmed ITA as an antimicrobial metabolite. The findings revealed insights into the biosynthesis of ITA and suggests its role in antimicrobial and anti-inflammatory activities in the innate immune system. This study also provided insights into the innate immune system of bivalves and highlighted the potential use of ITA as a biomarker for shellfish health assessment in aquaculture.
    Keywords:  Antimicrobial metabolite; Biomarkers; Itaconic acid; Metabolomics; Mollusc innate immunity; Vibrio
    DOI:  https://doi.org/10.1007/s11306-019-1556-8
  55. Mar Drugs. 2019 Jun 21. pii: E368. [Epub ahead of print]17(6):
    Park JH, Lee NK, Lim HJ, Mazumder S, Kumar Rethineswaran V, Kim YJ, Jang WB, Ji ST, Kang S, Kim DY, Van LTH, Giang LTT, Kim DH, Ha JS, Yun J, Kim H, Han J, Mishchenko NP, Fedoreyev SA, Vasileva EA, Kwon SM, Baek SH.
      Cardiac progenitor cells (CPCs) are resident stem cells present in a small portion of ischemic hearts and function in repairing the damaged heart tissue. Intense oxidative stress impairs cell metabolism thereby decreasing cell viability. Protecting CPCs from undergoing cellular apoptosis during oxidative stress is crucial in optimizing CPC-based therapy. Histochrome (sodium salt of echinochrome A-a common sea urchin pigment) is an antioxidant drug that has been clinically used as a pharmacologic agent for ischemia/reperfusion injury in Russia. However, the mechanistic effect of histochrome on CPCs has never been reported. We investigated the protective effect of histochrome pretreatment on human CPCs (hCPCs) against hydrogen peroxide (H2O2)-induced oxidative stress. Annexin V/7-aminoactinomycin D (7-AAD) assay revealed that histochrome-treated CPCs showed significant protective effects against H2O2-induced cell death. The anti-apoptotic proteins B-cell lymphoma 2 (Bcl-2) and Bcl-xL were significantly upregulated, whereas the pro-apoptotic proteins BCL2-associated X (Bax), H2O2-induced cleaved caspase-3, and the DNA damage marker, phosphorylated histone (γH2A.X) foci, were significantly downregulated upon histochrome treatment of hCPCs in vitro. Further, prolonged incubation with histochrome alleviated the replicative cellular senescence of hCPCs. In conclusion, we report the protective effect of histochrome against oxidative stress and present the use of a potent and bio-safe cell priming agent as a potential therapeutic strategy in patient-derived hCPCs to treat heart disease.
    Keywords:  cardiac progenitor cells; cell therapy; echinochrome A; histochrome; oxidative stress
    DOI:  https://doi.org/10.3390/md17060368
  56. ACS Nano. 2019 Jun 26.
    Jia TT, Yang G, Mo SJ, Wang ZY, Li BJ, Ma W, Guo YX, Chen X, Zhao X, Liu JQ, Zang SQ.
      Gold nanoclusters have become promising radiosensitizers due to their ultrasmall size and robust ability to adsorb, scatter and re-emit radiation. However, most of the previously reported gold nanocluster radiosensitizers do not have a precise atomic structure, causing difficulties in understanding the structure-activity relationship. In this study, a structurally defined gold-levonorgestrel nanocluster consisting of Au8(C21H27O2)8 (Au8NC) with bright luminescence (58.7% quantum yield) and satisfactory biocompatibility was demonstrated as a nanoradiosensitizer. When the Au8NCs were irradiated with X-rays, they produced reactive oxygen species (ROS), resulting in irreversible cell apoptosis. As indicated by in vivo tumor formation experiments, tumorigenicity was signi?cantly suppressed after one radiotherapy treatment with the Au8NCs. In addition, compared with tumors treated with X-rays (4 Gy) alone, tumors treated with the nanosensitizer exhibited an inhibition rate of 74.2%. This study contributes to the development of atomically precise gold nanoclusters as efficient radiosensitizers.
    DOI:  https://doi.org/10.1021/acsnano.9b03767
  57. Iran J Basic Med Sci. 2019 Jun;22(6): 617-622
    Mirarab E, Hojati V, Vaezi G, Shiravi A, Khaksari M.
      Objectives: Obestatin is a newly discovered peptide with antioxidant activities in different animal models. Recent studies have shown that Obestatin inhibits apoptosis following cardiac ischemia/reperfusion injury. Brain ischemia/reperfusion induces irreversible damage especially in the hippocampus area. This study aimed at examining the protective impact of Obestatin on apoptosis, protein expression and reactive astrogliosis level in hippocampal CA1 region of rat following transient global cerebral ischemia.Materials and Methods: Forty-eight male Wistar rats were randomly assigned into 4 groups (sham, ischemia/reperfusion, ischemia/reperfusion+ Obestatin 1, and 5 µg/kg, n=12). Ischemia induced occlusion of both common carotid arteries for 20 min. Obestatin 1 and 5 µg/kg were injected intraperitoneally at the beginning of reperfusion period and 24 and 48 hr after reperfusion. Assessment of the antioxidant enzymes and tumor necrosis factor alpha (TNF-α) was performed by ELISA method. Caspase-3 and glial fibrillary acidic protein (GFAP) proteins expression levels were evaluated by immunohistochemical staining 7 days after ischemia.
    Results: Based on the result of the current study, lower superoxide dismutase (SOD) and glutathione (GSH) (P<0.05) and higher malondialdehyde (MDA) and TNF-α levels were observed in the ischemia group than those of the sham group (P<0.01). Obestatin treatment could increase both SOD and GSH (P<0.05) and reduce MDA and TNF-α (P<0.05) versus the ischemia group. Moreover, obestatin could significantly decrease caspase-3 and GFAP positive cells in the CA1 region of hippocampus (P<0.01).
    Conclusion: Obestatin exerts protective effects against ischemia injury by inhibition of astrocytes activation and decreases neuronal cell apoptosis via its antioxidant properties.
    Keywords:  Apoptosis; Astrogliosis; Brain ischemia Hippocampus; Obestatin
    DOI:  https://doi.org/10.22038/ijbms.2019.34118.8110
  58. Chemosphere. 2019 Jun 15. pii: S0045-6535(19)31336-0. [Epub ahead of print]234 579-588
    Li S, Jiang X, Luo Y, Zhou B, Shi M, Liu F, Sha A.
      Mercury (Hg), a significant toxic metal for nephrotoxicity, can be found in food (vegetable and seafood) and drinking water by contamination. Oxidative stress is involved in inorganic Hg-induced nephrotoxicity, but the Sirtuin1 (Sirt1)/Nrf2/OH-1 pathway and sodium (Na)/calcium (Ca) ions actions in mercuric chloride (HgCl2)-induced nephrotoxicity remains unclear to date. In this study, Kunming mice were treated HgCl2 (5 mg/kg) for 24 h to evaluate potential mechanism. Here, along with Sirt1 activation, pale kidney, hisologic conditions, typical apoptotic changes and TUNEL positive nuclei were observed under acute HgCl2 exposure. Specifically, although HgCl2 increased the expression of Nrf2, Keap1, OH-1 and NQO1, the mRNA levels of GSS, GCLC and GCLM showed no significant alterations in mice kidney. Moreover, mice exposed to HgCl2 decreased the concentrations of Mg, K, P, Mn, Fe, Zn, and elevated Na, Ca, Cu and Se in kidney. It was also observed that HgCl2 suppressed the ATPases (Na+-K+-ATPase, Ca2+-ATPase, Mg2+-ATPase and Ca2+-Mg2+-ATPase) activities and decreased the mRNA levels of Atp1a1, Atp1a2 in the kidney. Further study showed that HgCl2 elevated Na+ concentrations by markedly increased the mRNA levels of Na+ transporter. The present study revealed that HgCl2 induced Sirt1/Nrf2/OH-1 pathway activation while did not inhibit apoptosis in kidney of mice. Additionally, HgCl2 regulates Na+ concentrations, which might create secondary disorders in absorption and excretion of other ions. Altogether we assume that Sirt1/Nrf2/Na+/Ca2+ pathway might be a potential therapeutic target for treating acute HgCl2 induced nephrotoxicity.
    Keywords:  Calcium; Kidney; Mercury; Nuclear factor E2 related factor 2; Sirtuin1; Sodium
    DOI:  https://doi.org/10.1016/j.chemosphere.2019.06.095
  59. Mol Cancer Res. 2019 Jun 25. pii: molcanres.1191.2018. [Epub ahead of print]
    Domingo-Vidal M, Whitaker-Menezes D, Martos-Rus C, Tassone P, Snyder CM, Tuluc M, Philp N, Curry J, Martinez-Outschoorn U.
      Head and neck squamous cell carcinoma (HNSCC) is comprised of metabolically linked distinct compartments. Cancer-associated fibroblasts (CAFs) and non-proliferative carcinoma cells display a glycolytic metabolism, whilst proliferative carcinoma cells rely on mitochondrial oxidative metabolism fueled by the catabolites provided by the adjacent CAFs. Metabolic coupling between these reprogrammed compartments contributes to HNSCC aggressiveness. In the current study, we examined the effects of cigarette smoke-exposed CAFs on metabolic coupling and tumor aggressiveness of HNSCC. Cigarette smoke (CS) extract was generated by dissolving cigarette smoke in growth media. Fibroblasts were cultured in CS or control media. HNSCC cells were co-cultured in vitro and co-injected in vivo with CS- or control fibroblasts. We found that CS induced oxidative stress, glycolytic flux and MCT4 expression, and senescence in fibroblasts. MCT4 upregulation was critical for fibroblast viability under CS conditions. The effects of CS on fibroblasts were abrogated by antioxidant treatment. Co-culture of carcinoma cells with CS-fibroblasts induced metabolic coupling with upregulation of the marker of glycolysis MCT4 in fibroblasts and markers of mitochondrial metabolism MCT1 and TOMM20 in carcinoma cells. CS-fibroblasts increased CCL2 expression and macrophage migration. Co-culture with CS-fibroblasts also increased two features of carcinoma cell aggressiveness: resistance to cell death and enhanced cell migration. Co-injection of carcinoma cells with CS-fibroblasts generated larger tumors with reduced apoptosis than control co-injections, and upregulation of MCT4 by CS exposure was a driver of these effects. We demonstrate that a tumor microenvironment exposed to CS is sufficient to modulate metabolism and cancer aggressiveness in HNSCC. Implications: Cigarette smoke shifts cancer-stroma towards glycolysis and induces head and neck cancer aggressiveness with a mitochondrial profile linked by catabolite transporters and oxidative stress.
    DOI:  https://doi.org/10.1158/1541-7786.MCR-18-1191
  60. Naunyn Schmiedebergs Arch Pharmacol. 2019 Jun 22.
    Li YQ, Peng JJ, Peng J, Luo XJ.
      Gasdermin E (GSDME), also called DFNA5, is a member of the gasdermin family. GSDME is involved in the regulation of apoptosis and necrosis. The N-terminal domain of GSDME displays an apoptosis-inducing activity while the C-terminal domain may serve as an apoptosis-inhibiting regulator by shielding the N-terminal domain. Besides its function in the regulation of apoptosis, GSDME was recently reported to be a substrate of caspase-3 and cleavage of GSDME by caspase-3 into necrotic N-terminal fragment leads to the induction of secondary necrosis. GSDME was first identified as a deafness gene because its mutation was associated with a specific form of autosomal dominant progressive sensorineural hearing loss. Furthermore, GSDME has been considered a tumor suppressor implicated in several types of cancer. This mini-review summarized recent reports relevant to the functions of GSDME in the regulation of apoptosis and necrosis as well as its clinical relevance.
    Keywords:  Apoptosis; Cancer; DFNA5; GSDME; Hearing loss; Secondary necrosis
    DOI:  https://doi.org/10.1007/s00210-019-01674-7
  61. Plant Direct. 2018 Aug;2(8): e00081
    Kessens R, Sorensen N, Kabbage M.
      Despite the importance of proper cell death regulation across broad evolutionary distances, an understanding of the molecular machinery underpinning this fundamental process in plants remains largely elusive. This is despite its critical importance to development, homeostasis, and proper responses to stress. The identification of endogenous plant regulators of cell death has been hindered by the fact that many core regulators of cell death in animals are absent in plant genomes. Remarkably, numerous studies have shown that the ectopic expression of animal prosurvival genes in plants can suppress cell death imposed by many stresses. In this study, we capitalize on the ectopic expression of one of these animal prosurvival genes, an inhibitor of apoptosis from Spodoptera frugiperda (SfIAP), to identify novel cell death regulators in plants. A yeast two-hybrid assay was conducted using SfIAP as bait to screen a tomato cDNA library. This screen identified several transcription factors of the SQUAMOSA promoter-binding protein (SBP) family as potential SfIAP binding partners. We confirmed this interaction in vivo for our top two interactors, SlySBP8b and SlySBP12a, using coimmunoprecipitation. Interestingly, overexpression of SlySBP8b and SlySBP12a induced cell death in Nicotiana benthamiana leaves. Overexpression of these two transcription factors also induced the accumulation of reactive oxygen species and enhanced the growth of the necrotrophic pathogen Alternaria alternata. Fluorescence microscopy confirmed the nuclear localization of both SlySBP8b and SlySBP12a, while SlySBP12a was also localized to the ER membrane. These results suggest a prodeath role for SlySBP8b and SlySBP12a and implicate ER membrane tethering as a means of regulating SlySBP12a activity.
    Keywords:  SQUAMOSA promoter‐binding protein; SQUAMOSA promoter‐binding protein‐like; cell death; fumonisin B1; inhibitor of apoptosis; necrotrophic
    DOI:  https://doi.org/10.1002/pld3.81
  62. J Cell Biochem. 2019 Jun 27.
    Burnett SB, Vaughn LS, Strom JM, Francois A, Patel RC.
      Protein Activator (PACT) activates the interferon (IFN)-induced double-stranded (ds) RNA-activated protein kinase (PKR) in response to stress signals. Oxidative stress and endoplasmic reticulum (ER) stress causes PACT-mediated PKR activation, which leads to phosphorylation of translation initiation factor eIF2α, inhibition of protein synthesis, and apoptosis. A dominantly inherited form of early-onset dystonia 16 (DYT16) has been identified to arise due to a frameshift (FS) mutation in PACT. To examine the effect of the resulting truncated mutant PACT protein on the PKR pathway, we examined the biochemical properties of the mutant protein and its effect on mammalian cells. Our results indicate that the FS mutant protein loses its ability to bind dsRNA as well as its ability to interact with PKR while surprisingly retaining the ability to interact with PACT and PKR-inhibitory protein TRBP. The truncated FS mutant protein, when expressed as a fusion protein with a N-terminal fluorescent mCherry tag aggregates in mammalian cells to induce apoptosis via activation of caspases both in a PKR- and PACT-dependent as well as independent manner. Our results indicate that interaction of FS mutant protein with PKR inhibitor TRBP can dissociate PACT from the TRBP-PACT complex resulting in PKR activation and consequent apoptosis. These findings are relevant to diseases resulting from protein aggregation especially since the PKR activation is a characteristic of several neurodegenerative conditions.
    Keywords:  DYT16; PACT; PKR; apoptosis; caspase; dystonia
    DOI:  https://doi.org/10.1002/jcb.29223
  63. Neurochem Res. 2019 Jun 24.
    Yao P, Li Y, Yang Y, Yu S, Chen Y.
      Tripterygium Wilfordii Hook F has been exploited as a treatment for several diseases due to its neuroprotective, anti-tumor, and anti-inflammatory effects. Triptolide is one of its key bioactive compounds. Currently, the role of triptolide in cognitive dysfunction remains unclear. Here, the role of triptolide on cognitive dysfunction was investigated using chronic cerebral hypoperfusion-induced vascular dementia (VD) rat model. SD rats were administrated with Triptolide (5 μg/kg) for 6 weeks after undergoing permanent bilateral common carotid artery occlusion. The results show that triptolide treatment conferred neuroprotective effects in VD rats. Intraperitoneal injection of triptolide attenuated oxidative stress, learning and memory deficits, and neuronal apoptosis in the hippocampi. Moreover, triptolide enhanced the expression of SIRT1, PGC-1α, ZO-1, Claudin-5, and decreased the serum levels of NSE and S100B significantly. It also improved CCH-induced learning and memory deficits, and this is attributed to its capacity to promote SIRT1/PGC-1α signaling, confer antioxidant effects, and inhibit neuronal apoptosis. These findings indicate that triptolide may be an effective therapeutic agent for vascular cognitive dysfunction.
    Keywords:  Cognitive dysfunction; Oxidative stress; PGC-1α; SIRT1; Triptolide
    DOI:  https://doi.org/10.1007/s11064-019-02831-3