bims-noxint Biomed News
on NADPH oxidases in tumorigenesis
Issue of 2020‒04‒26
eleven papers selected by
Laia Caja Puigsubira
Uppsala University

  1. Acta Physiol (Oxf). 2020 Apr 20.
    Xu N, Jiang S, Persson PB, Persson EA, Lai EY, Patzak A.
      Reactive oxygen species (ROS) are produced by the aerobic metabolism. The imbalance between production of ROS and antioxidant defense in any cell compartment is associated with cell damage and may play an important role in the pathogenesis of renal disease. NADPH oxidase (NOX) family is the major ROS source in the vasculature and modulates renal perfusion. Upregulation of Ang II and adenosine activate NOX via AT1R and A1R in renal microvessels, leading to superoxide production. Oxidative stress in the kidney prompts renal vascular remodeling and increases preglomerular resistance. These are key elements in hypertension, acute- and chronic kidney injury, as well as diabetic nephropathy. Renal afferent arterioles (Af), the primary resistance vessel in the kidney, fine tune renal hemodynamics and impact on blood pressure. Vice versa, ROS increase in hypertension and diabetes, resulting in upregulation of Af vasoconstriction, enhancement of myogenic responses and change of tubuloglomerular feedback (TGF), which further promotes hypertension and diabetic nephropathy. In the following, we highlight oxidative stress in the function and dysfunction of renal hemodynamics. The renal microcirculatory alterations brought about by ROS importantly contribute to the pathophysiology of kidney injury, hypertension, and diabetes.
    Keywords:  Reactive oxygen species; afferent arteriole; hypertension; renal microvasculature; vasa recta
  2. Adv Exp Med Biol. 2020 ;1254 37-46
    Tsubata T.
      Reactive oxygen species (ROS) are not only toxic substances inducing oxidative stress but also play a role in receptor signaling as a second messenger, which augments signaling through various receptors by oxidizing ROS-sensitive signaling molecules. Among ROS, H2O2 is suggested to be an important second messenger because of its relative stability. H2O2 is generated by superoxide dismutase (SOD)-mediated conversion of superoxide produced by membrane-localized NADPH oxidases (NOXes). Superoxide and H2O2 are also produced as a by-product of mitochondrial respiratory chain and various other metabolic reactions. BCR ligation induces ROS production in two phases. ROS production starts immediately after BCR ligation and ceases in 1 h, then re-starts 2 h after BCR ligation and lasts 4-6 h. ROS production in the early phase is mediated by NOX2, a NOX isoform, but does not regulate BCR signaling. In contrast, ROS production at the late phase augments BCR signaling. Although the involvement of mitochondrial respiration was previously suggested in prolonged BCR ligation-induced ROS production, we recently demonstrated that NOX3, another NOX isoform, plays a central role in ROS production at the late phase. NOXes are shown to be a component of ROS-generating signaling endosome called redoxosome together with endocytosed receptors and receptor-associated signaling molecules. In redoxosome, ROS generated by NOXes augment signaling through the endocytosed receptor. The role of NOXes and redoxosome in BCR signaling needs to be further elucidated.
    Keywords:  BCR signaling; NADPH oxidases; Reactive oxygen species; Second messenger
  3. CNS Neurosci Ther. 2020 Apr 24.
    Liu YS, Gu H, Huang TC, Wei XW, Ma W, Liu D, He YW, Luo WT, Huang JT, Zhao D, Jia SS, Wang F, Zhang T, Bai YZ, Wang WL, Yuan ZW.
      AIMS: Failure of neural tube closure resulting from excessive apoptosis leads to neural tube defects (NTDs). NADPH oxidase 4 (NOX4) is a critical mediator of cell growth and death, yet its role in NTDs has never been characterized. NOX4 is a potential target of miR-322, and we have previously demonstrated that miR-322 was involved in high glucose-induced NTDs. In this study, we investigated the effect of NOX4 on the embryonic neuroepithelium in NTDs and reveal a new regulatory mechanism for miR-322 that disrupts neurulation by ameliorating cell apoptosis.METHODS: All-trans-retinoic acid (ATRA)-induced mouse model was utilized to study NTDs. RNA pull-down and dual-luciferase reporter assays were used to confirm the interaction between NOX4 and miR-322. In mouse neural stem cells and whole-embryo culture, Western blot and TUNEL were carried out to investigate the effects of miR-322 and NOX4 on neuroepithelium apoptosis in NTD formation.
    RESULTS: NOX4, as a novel target of miR-322, was upregulated in ATRA-induced mouse model of NTDs. In mouse neural stem cells, the expression of NOX4 was inhibited by miR-322; still further, NOX4-triggered apoptosis was also suppressed by miR-322. Moreover, in whole-embryo culture, injection of the miR-322 mimic into the amniotic cavity attenuated cell apoptosis in NTD formation by silencing NOX4.
    CONCLUSION: miR-322/NOX4 plays a crucial role in apoptosis-induced NTD formation, which may provide a new understanding of the mechanism of embryonic NTDs and a basis for potential therapeutic target against NTDs.
    Keywords:  NADPH oxidase 4; all-trans-retinoic acid; apoptosis; miR-322; neural tube defects
  4. Antioxidants (Basel). 2020 Apr 16. pii: E324. [Epub ahead of print]9(4):
    Ghosh AK, Rao VR, Wisniewski VJ, Zigrossi AD, Floss J, Koulen P, Stubbs EB, Kaja S.
      Optic nerve head astrocytes are the specialized glia cells that provide structural and trophic support to the optic nerve head. In response to cellular injury, optic nerve head astrocytes undergo reactive astrocytosis, the process of cellular activation associated with cytoskeletal remodeling, increases in the rate of proliferation and motility, and the generation of Reactive Oxygen Species. Antioxidant intervention has previously been proposed as a therapeutic approach for glaucomatous optic neuropathy, however, little is known regarding the response of optic nerve head astrocytes to antioxidants under physiological versus pathological conditions. The goal of this study was to determine the effects of three different antioxidants, manganese (III) tetrakis (1-methyl-4-pyridyl) porphyrin (Mn-TM-2-PyP), resveratrol and xanthohumol in primary optic nerve head astrocytes. Effects on the expression of the master regulator nuclear factor erythroid 2-related factor 2 (Nrf2), the antioxidant enzyme, manganese-dependent superoxide dismutase 2 (SOD2), and the pro-oxidant enzyme, nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4), were determined by quantitative immunoblotting. Furthermore, efficacy in preventing chemically and reactive astrocytosis-induced increases in cellular oxidative stress was quantified using cell viability assays. The results were compared to the effects of the prototypic antioxidant, Trolox. Antioxidants elicited highly differential changes in the expression levels of Nrf2, SOD2, and NOX4. Notably, Mn-TM-2-PyP increased SOD2 expression eight-fold, while resveratrol increased Nrf2 expression three-fold. In contrast, xanthohumol exerted no statistically significant changes in expression levels. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) uptake and lactate dehydrogenase (LDH) release assays were performed to assess cell viability after chemically and reactive astrocytosis-induced oxidative stress. Mn-TM-2-PyP exerted the most potent glioprotection by fully preventing the loss of cell viability, whereas resveratrol and xanthohumol partially restored cell viability. Our data provide the first evidence for a well-developed antioxidant defense system in optic nerve head astrocytes, which can be pharmacologically targeted by different classes of antioxidants.
    Keywords:  cell viability; glioprotection; manganese porphyrin; optic nerve head astrocytes; phase II antioxidant enzymes; resveratrol; xanthohumol
  5. Drug Des Devel Ther. 2020 ;14 1377-1389
    Fan H, Li D, Guan X, Yang Y, Yan J, Shi J, Ma R, Shu Q.
      Introduction: Demyelination causes neurological deficits involving visual, motor, sensory symptoms. Deregulation of several enzymes has been identified in demyelination, which holds potential for the development of treatment strategies for demyelination. However, the specific effect of methionine sulfoxide reductase A (MsrA) on demyelination remains unclear. Hence, this study aims to explore the effect of MsrA on oxidative stress and inflammatory response of microglia in demyelination.Methods: Initially, we established a mouse model with demyelination induced by cuprizone and a cell model provoked by lipopolysaccharide (LPS). The expression of MsrA in wild-type (WT) and MsrA-knockout (MsrA-/-) mice were determined by RT-qPCR and Western blot analysis. In order to further explore the function of MsrA on inflammatory response, and oxidative stress in demyelination, we detected the expression of microglia marker Iba1, inflammatory factors TNF-α and IL-1β and intracellular reactive oxygen species (ROS), superoxide dismutase (SOD) activity, as well as expression of the NOX2-MAPKs/NF-κB signaling pathway-related genes in MsrA-/- mice and LPS-induced microglia following different treatments.
    Results: MsrA expression was downregulated in MsrA-/- mice. MsrA silencing was shown to produce severely injured motor coordination, increased expressions of Iba1, TNF-α, IL-1β, ROS and NOX2, and extent of ERK, p38, IκBα, and p65 phosphorylation, but reduced SOD activity. Conjointly, our study suggests that Tat-MsrA fusion protein can prevent the cellular inflammatory response and subsequent demyelination through negative regulation of the NOX2-MAPKs/NF-κB signaling pathway.
    Conclusion: Our data provide a profound insight on the role of endogenous antioxidative defense systems such as MsrA in controlling microglial function.
    Keywords:  MsrA; NOX2-MAPKs/NF-κB signaling pathway; demyelination; inflammatory activation; microglia; oxidative stress
  6. Cell Death Differ. 2020 Apr 20.
    Tan MWY, Sng MK, Cheng HS, Low ZS, Leong BJJ, Chua D, Tan EHP, Chan JSK, Yip YS, Lee YH, Pal M, Wang X, Wahli W, Tan NS.
      The incidence of nonmelanoma skin cancer (NMSC) has been increasing worldwide. Most studies have highlighted the importance of cancer-associated fibroblasts (CAFs) in NMSC progression. However much less is known about the communication between normal fibroblasts and epithelia; disruption of this communication affects tumor initiation and the latency period in the emergence of tumors. Delineating the mechanism that mediates this epithelial-mesenchymal communication in NMSC could identify more effective targeted therapies. The nuclear receptor PPARβ/δ in fibroblasts has been shown to modulate adjacent epithelial cell behavior, however, its role in skin tumorigenesis remains unknown. Using chemically induced skin carcinogenesis, we showed that FSPCre-Pparb/dex4 mice, whose Pparb/d gene was selectively deleted in fibroblasts, had delayed emergence and reduced tumor burden compared with control mice (Pparb/dfl/fl). However, FSPCre-Pparb/dex4-derived tumors showed increased proliferation, with no difference in differentiation, suggesting delayed tumor initiation. Network analysis revealed a link between dermal Pparb/d and TGF-β1 with epidermal NRF2 and Nox4. In vitro investigations showed that PPARβ/δ deficiency in fibroblasts increased epidermal Nox4-derived H2O2 production, which triggered an NRF2-mediated antioxidant response. We further showed that H2O2 upregulated NRF2 mRNA via the B-Raf-MEK1/2 pathway. The enhanced NRF2 response altered the activities of PTEN, Src, and AKT. In vivo, we detected the differential phosphorylation profiles of B-Raf, MEK1/2, PTEN, Src, and AKT in the vehicle-treated and chemically treated epidermis of FSPCre-Pparb/dex4 mice compared with that in Pparb/dfl/fl mice, prior to the first appearance of tumors in Pparb/dfl/fl. Our study revealed a role for fibroblast PPARβ/δ in the epithelial-mesenchymal communication involved in cellular redox homeostasis.
  7. Can J Physiol Pharmacol. 2020 Apr 20.
    Sun J, Zhang L, Fang J, Yang S, Chen L.
      Galectin-3 is a member of the β-galactoside-binding lectin family taken part in the regulation of inflammation, angiogenesis, and fibrosis. This study was designed to study the improved effect of galectin-3 inhibition on diabetic cardiomyopathy (DCM). Sprague-Dawley rats were randomized into the control, DCM, and DCM + modified citrus pectin (MCP, a galectin-3 pharmacological inhibitor) groups. After 8 weeks, streptozotocin (STZ)-induced DCM led to high blood glucose level, oxidative stress, cardiac injury, and dysfunction, accompanied by suppressed body weight. On the contrary, MCP (100 mg/kg/day) administration improved body weight and blood glucose level and attenuated cardiac injury and dysfunction in DCM rats. Additionally, MCP attenuated pathological changes in plasma and myocardial tissue markers of oxidative stress, such as hydrogen peroxide and malonydialdehyde, although it did not change superoxide dismutase (SOD) activities, which were decreased in the DCM group. The levels of oxidative stress-associated proteins evaluated by Western blot, such as p67phox and NADPH oxidase (NOX) 4, were obviously increased in the DCM group, while it was reversed by MCP treatment. Therefore, galectin-3 mediated high-glucose-induced cardiomyocyte injury, and galectin-3 inhibition attenuated DCM by suppressing NADPH oxidase. These findings suggested that galectin-3 could be a potential target for treatment of patients with DCM.
  8. J Hepatol. 2020 Apr 17. pii: S0168-8278(20)30228-2. [Epub ahead of print]
    Okina Y, Sato-Matsubara M, Matsubara T, Daikoku A, Longato L, Rombouts K, Thanh Thuy LT, Ichikawa H, Minamiyama Y, Kadota M, Fujii H, Enomoto M, Ikeda K, Yoshizato K, Pinzani M, Kawada N.
      BACKGROUND AND AIMS: Cytoglobin (CYGB) is a respiratory protein that acts as a scavenger of reactive oxygen species. Although CYGB is expressed uniquely in hepatic stellate cells (HSCs) in the liver, the molecular role of CYGB in human HSC activation and human liver disease remains uncharacterised. The aim of this study was to reveal the mechanism by which TGF-β1/SMAD2 pathway regulates human CYGB promoter and the pathophysiological function of CYGB in human non-alcoholic steatohepatitis (NASH).METHODS: Immunohistochemical staining was performed using human NASH biopsy specimens. Molecular and biochemical analysis were performed by western blotting, quantitative PCR, and luciferase and immunoprecipitation assays. Hydroxyl radicals (•OH) and oxidative DNA damage were measured using an •OH-detectable probe and 8-hydroxy-2'-deoxyguanosine (8-OHdG) ELISA.
    RESULTS: In culture, TGF-β1-pretreated human hepatic stellate cells (HHSteCs) exhibited lowered CYGB levels together with increased NADPH oxidase 4 (NOX4) expression and were primed for H2O2-triggered OH production and 8-OHdG generation. Overexpression of human CYGB in HHSteCs cancelled out those effects of TGF-β1. Electron spin resonance demonstrated direct •OH-scavenging activity of recombinant human CYGB. Mechanistically, pSMAD2 reduced CYGB transcription by recruiting the M1 repressor isoform of SP3 to the human CYGB promoter at nucleotide positions +2-+13 from the transcription start site. The same repression did not occur on the mouse Cygb promoter. TGF-β1/SMAD3 mediated αSMA and collagen expression. Consistent with those observations in cultured HHSteCs, CYGB expression was negligible, but 8-OHdG was abundant, in activated αSMA+pSMAD2+- and αSMA+NOX4+-positive hepatic stellate cells from human NASH patients with advanced fibrosis.
    CONCLUSIONS: Downregulation of CYGB by the TGF-β1/pSMAD2/SP3-M1 pathway brings about •OH-dependent oxidative DNA damage in activated hepatic stellate cells from human patients with NASH.
    Keywords:  NAFLD/NASH; TGF-β1; cytoglobin; hepatic stellate cells; liver fibrosis; oxidative stress
  9. Cells. 2020 Apr 22. pii: E1035. [Epub ahead of print]9(4):
    Centner AM, Bhide PG, Salazar G.
      Cigarette smoke is a known exacerbator of age-related pathologies, such as cardiovascular disease (CVD), atherosclerosis, and cellular aging (senescence). However, the role of nicotine and its major metabolite cotinine is yet to be elucidated. Considering the growing amount of nicotine-containing aerosol use in recent years, the role of nicotine is a relevant public health concern. A number of recent studies and health education sites have focused on nicotine aerosol-induced adverse lung function, and neglected cardiovascular (CV) impairments and diseases. A critical review of the present scientific literature leads to the hypothesis that nicotine mediates the effects of cigarette smoke in the CV system by increasing MAPK signaling, inflammation, and oxidative stress through NADPH oxidase 1 (Nox1), to induce vascular smooth muscle cell (VSMC) senescence. The accumulation of senescent VSMCs in the lesion cap is detrimental as it increases the pathogenesis of atherosclerosis by promoting an unstable plaque phenotype. Therefore, nicotine, and most likely its metabolite cotinine, adversely influence atherosclerosis.
    Keywords:  ApoE−/−; VSMC; atherosclerosis; cigarette smoke; cotinine; nicotine; senescence
  10. Free Radic Res. 2020 Apr 24. 1-13
    Kvandova M, Filippou K, Steven S, Oelze M, Kalinovic S, Stamm P, Frenis K, Vujacic-Mirski K, Sakumi K, Nakabeppu Y, Bagheri Hosseinabadi M, Dovinova I, Epe B, Münzel T, Kröller-Schön S, Daiber A.
      Background: Large epidemiological studies point towards a link between the incidence of arterial hypertension, ischaemic heart disease, metabolic disease and exposure to traffic noise, supporting the role of noise exposure as an independent cardiovascular risk factor. We characterised the underlying molecular mechanisms leading to noise-dependent adverse effects on the vasculature and myocardium in an animal model of aircraft noise exposure and identified oxidative stress and inflammation as central players in mediating vascular and cardiac dysfunction. Here, we studied the impact of noise-induced oxidative DNA damage on vascular function in DNA-repair deficient 8-oxoguanine glycosylase knockout (Ogg1-/-) mice.Methods and results: Noise exposure (peak sound levels of 85 and mean sound level of 72 dB(A) applied for 4d) caused oxidative DNA damage (8-oxoguanine) and enhanced NOX-2 expression in C57BL/6 mice with synergistic increases in Ogg1-/- mice (shown by immunohistochemistry). A similar pattern was found for oxidative burst of blood leukocytes and other markers of oxidative stress (4-hydroxynonenal, 3-nitrotyrosine) and inflammation (cyclooxygenase-2). We observed additive impairment of noise exposure and genetic Ogg1 deficiency on endothelium-independent relaxation (nitroglycerine), which may be due to exacerbated oxidative DNA damage leading to leukocyte activation and oxidative aldehyde dehydrogenase inhibition.Conclusions: The finding that chronic noise exposure causes oxidative DNA damage in mice is worrisome since these potential mutagenic lesions could contribute to cancer progression. Human field studies have to demonstrate whether oxidative DNA damage is also found in urban populations with high levels of noise exposure as recently shown for workers with high occupational noise exposure.
    Keywords:  Environmental stressor; endothelial dysfunction; noise exposure; oxidative DNA damage; oxidative stress
  11. Toxicol In Vitro. 2020 Apr 16. pii: S0887-2333(20)30050-3. [Epub ahead of print] 104867
    Kodandaraman G, Bankoglu EE, Stopper H.
      Endogenous hormones systemically regulate the growth and metabolism and some prior studies have shown that their imbalance can have a potential to induce genomic damage in in vitro and animal models. Some conditions that are associated with elevated levels of endogenous hormones are hyperinsulinemia and intense exercise-induced stress causing increased adrenaline. In this study we test whether these two hormones, could cause an additive increase in genomic damage and whether they have an overlapping mechanism of action. For this, we use the human promyelocytic HL60 cells, as they express the receptors for both hormones. At doses taken from the saturation level of the individual dose response curves, no additivity in genomic damage was detected through micronucleus induction. This hints towards a common step in the pathway, which is under these conditions fully activated by each of the individual hormone. To investigate this further, individual and common parts in insulin and adrenaline signalling such as their respective hormone receptors, the downstream protein AKT and the involvement of mitochondria and NADPH oxidase (NOX) enzymes were studied. The results indicate no additive effect of high hormone concentrations in genomic damage in the in vitro model, which may be due to exhaustion of the NOX 2-mediated reactive oxygen production. It remains to be determined whether a similar situation may occur in in vivo situations.
    Keywords:  Adrenaline; HL60 cells; Insulin; Micronucleus test; NOX 2