bims-noxint 2022-02-27 papers

bims-noxint

Biomed News

on NADPH oxidases in tumorigenesis

Issue of 2022–02–27
seven papers selected by
Laia Caja Puigsubira, Uppsala University

Identification of the NADPH Oxidase (Nox) Subtype and the Source of Superoxide Production in the Micturition Centre.
NOX4 regulates TGFβ-induced proliferation and self-renewal in glioblastoma stem cells.
Aryl Hydrocarbon Receptor Inhibition Restores Indoxyl Sulfate-Mediated Endothelial Dysfunction in Rat Aortic Rings.
Induction of apoptosis and autosis in cardiomyocytes by the combination of homocysteine and copper via NOX-mediated p62 expression.
Folic Acid Homeostasis and Its Pathways Related to Hepatic Oxidation in Adolescent Rats Exposed to Binge Drinking.
NADPH-derived ROS generation drives fibrosis and endothelial-to-mesenchymal transition in systemic sclerosis: Potential cross talk with circulating miRNAs.
Icariin inhibits RANKL-induced osteoclastogenesis in RAW264.7 cells via inhibition of reactive oxygen species production by reducing the expression of NOX1 and NOX4.

Biology (Basel). 2022 Jan 24. pii: 183. [Epub ahead of print]11(2):

Identification of the NADPH Oxidase (Nox) Subtype and the Source of Superoxide Production in the Micturition Centre.

Qin Wu, Ayse Gurpinar, Maxwell Roberts, Patrizia Camelliti, Michael R Ruggieri, Changhao Wu.

  Oxidative inflammatory damage to specialised brain centres may lead to dysfunction of their associated peripheral organs, such as the bladder. However, the source of reactive oxygen species (ROS) in specific brain regions that regulate bladder function is poorly understood. Of all ROS-generating enzymes, the NADPH oxidase (Nox) family produces ROS as its sole function and offers an advantage over other enzymes as a drug-targetable molecule to selectively control excessive ROS. We investigated whether the Nox 2 subtype is expressed in the micturition regulatory periaqueductal gray (PAG) and Barrington's nucleus (pontine micturition centre, PMC) and examined Nox-derived ROS production in these structures. C57BL/6J mice were used; PAG, PMC, cardiac tissue, and aorta were isolated. Western blot determined Nox 2 expression. Lucigenin-enhanced chemiluminescence quantified real-time superoxide production. Western blot experiments demonstrated the presence of Nox 2 in PAG and PMC. There was significant NADPH-dependent superoxide production in both brain tissues, higher than that in cardiac tissue. Superoxide generation in these brain tissues was significantly suppressed by the Nox inhibitor diphenyleneiodonium (DPI) and also reduced by the Nox-2 specific inhibitor GSK2795039, comparable to aorta. These data provide the first evidence for the presence of Nox 2 and Nox-derived ROS production in micturition centres.

Keywords:  NADPH oxidase (Nox); aging; bladder; periaqueductal gray (PAG); pontine micturition centre (PMC); reactive oxygen species (ROS)

DOI:  https://doi.org/10.3390/biology11020183
Mol Oncol. 2022 Feb 24.

NOX4 regulates TGFβ-induced proliferation and self-renewal in glioblastoma stem cells.

Pedro García-Gómez, Irene Golán, Mahsa S Dadras, Artur Mezheyeuski, Claudia Bellomo, Kalliopi Tzavlaki, Anita Morén, Jordi Carreras-Puigvert, Laia Caja.

  Glioblastoma (GBM) is the most aggressive and common glioma subtype, with a median survival of 15 months after diagnosis. Current treatments have limited therapeutic efficacy; thus, more effective approaches are needed. The glioblastoma tumoral mass is characterized by a small cellular subpopulation - glioblastoma stem cells (GSCs) - that has been held responsible for glioblastoma initiation, cell invasion, proliferation, relapse and resistance to chemo- and radiotherapy. Targeted therapies against GSCs are crucial, as is understanding the molecular mechanisms that govern the GSCs. Transforming growth factor β (TGFβ) signaling and reactive oxygen species (ROS) production are known to govern and regulate cancer stem cell biology. Among the differentially expressed genes regulated by TGFβ in a transcriptomic analysis of two different patient-derived GSCs, we found NADPH oxidase 4 (NOX4) as one of the top upregulated genes. Interestingly, when patient tissues were analyzed, NOX4 expression was found to be higher in GSCs versus differentiated cells. A functional analysis of the role of NOX4 downstream of TGFβ in several patient-derived GSCs showed that TGFβ does indeed induce NOX4 expression and increases ROS production in a NOX4-dependent manner. NOX4 downstream of TGFβ regulates GSC proliferation and NOX4 expression is necessary for TGFβ-induced expression of stem cell markers and of the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2), which in turn controls the cell's antioxidant and metabolic responses. Interestingly, overexpression of NOX4 recapitulates the effects induced by TGFβ in GSCs: enhanced proliferation, stemness and NRF2 expression. In conclusion, this work functionally establishes NOX4 as a key mediator of GSC biology.

Keywords:  NOX4; ROS; TGFβ; glioblastoma; proliferation; stem cells

DOI:  https://doi.org/10.1002/1878-0261.13200
Toxins (Basel). 2022 Jan 26. pii: 100. [Epub ahead of print]14(2):

Aryl Hydrocarbon Receptor Inhibition Restores Indoxyl Sulfate-Mediated Endothelial Dysfunction in Rat Aortic Rings.

Cindy Nguyen, Amanda J Edgley, Darren J Kelly, Andrew R Kompa.

  The uremic toxin indoxyl sulfate (IS), elevated in chronic kidney disease (CKD), is known to contribute towards progressive cardiovascular disease. IS activates the aryl hydrocarbon receptor (AhR) mediating oxidative stress and endothelial dysfunction via activation of the CYP1A1 pathway. The present study examines AhR inhibition with the antagonist, CH223191, on IS-mediated impairment of vascular endothelial function and disruption of redox balance. The acute effects of IS on endothelium-dependent relaxation were assessed in aortic rings from Sprague Dawley rats exposed to the following conditions: (1) control; (2) IS (300 μM); (3) IS + CH223191 (1 μM); (4) IS + CH223191 (10 μM). Thereafter, tissues were assessed for changes in expression of redox markers. IS reduced the maximum level of endothelium-dependent relaxation (Rmax) by 42% (p < 0.001) compared to control, this was restored in the presence of increasing concentrations of CH223191 (p < 0.05). Rings exposed to IS increased expression of CYP1A1, nitro-tyrosine, NADPH oxidase 4 (NOX4), superoxide, and reduced eNOS expression (p < 0.05). CH223191 (10 μM) restored expression of these markers back to control levels (p < 0.05). These findings demonstrate the adverse impact of IS-mediated AhR activation on the vascular endothelium, where oxidative stress may play a critical role in inducing endothelial dysfunction in the vasculature of the heart and kidneys. AhR inhibition could provide an exciting novel therapy for CVD in the CKD setting.

Keywords:  aryl hydrocarbon receptor; cardiovascular disease; chronic kidney disease; endothelial dysfunction; indoxyl sulfate; oxidative stress

DOI:  https://doi.org/10.3390/toxins14020100
Cell Death Discov. 2022 Feb 21. 8(1): 75

Induction of apoptosis and autosis in cardiomyocytes by the combination of homocysteine and copper via NOX-mediated p62 expression.

Ran Yin, Huan Wang, Chun Li, Lulu Wang, Songqing Lai, Xianhe Yang, Daojun Hong, Wan Zhang.

High levels of homocysteine (Hcy) associated with cardiovascular events are accompanied by increased copper (Cu) concentrations in the blood. Hcy has been shown to promote endothelial dysfunction, whereas the effect of Hcy on cardiomyocytes and the role of Cu in the pathogenesis remain less understood. In the present study, it is demonstrated that the combination of Hcy and Cu2+-induced apoptosis and autosis of cardiomyocytes simultaneously, and thus led to cardiac dysfunction in hyperhomocysteinemic rats. These effects were associated with p22phox activation and NADPH oxidase (NOX)-mediated p62 upregulation. Inhibition of the expression of p22phox or p62 in cardiomyocytes significantly attenuated Hcy and Cu2+-mediated reactive oxygen species (ROS) generation and cell death. Furthermore, interrupting the NOX-p62 axis prevented diastolic dysfunction in hyperhomocysteinemic rats (HcyR). These findings establish that the induction of apoptosis and autosis of cardiomyocytes through stimulating the NOX-p62-signaling pathway constitutes a novel mechanism of Hcy and Cu-induced cardiac dysfunction.

DOI: https://doi.org/10.1038/s41420-022-00870-4
Antioxidants (Basel). 2022 Feb 11. pii: 362. [Epub ahead of print]11(2):

Folic Acid Homeostasis and Its Pathways Related to Hepatic Oxidation in Adolescent Rats Exposed to Binge Drinking.

María Del Carmen Gallego-Lopez, María Luisa Ojeda, Inés Romero-Herrera, Fátima Nogales, Olimpia Carreras.

  Chronic ethanol consumption and liver disease are intimately related to folic acid (FA) homeostasis. Despite the fact that FA decreases lipid oxidation, its mechanisms are not yet well elucidated. Lately, adolescents have been practising binge drinking (BD), consisting of the intake of a high amount of alcohol in a short time; this is a particularly pro-oxidant form of consumption. The aim of this study is to examine, for the first time, FA homeostasis in BD adolescent rats and its antioxidant properties in the liver. We used adolescent rats, including control rats and rats exposed to an intermittent intraperitoneal BD model, supplemented with or without FA. Renal FA reabsorption and renal FA deposits were increased in BD rats; hepatic deposits were decreased, and heart and serum levels remained unaffected. This depletion in the liver was accompanied by higher transaminase levels; an imbalance in the antioxidant endogenous enzymatic system; lipid and protein oxidation; a decrease in glutathione (GSH) levels; hyper-homocysteinemia (HHcy); an increase in NADPH oxidase (NOX) 1 and NOX4 enzymes; an increase in caspase 9 and 3; and a decrease in the anti-apoptotic metallopeptidase inhibitor 1. Furthermore, BD exposure increased the expression of uncoupled endothelial nitric oxide synthase (eNOS) by increasing reactive nitrogen species generation and the nitration of tyrosine proteins. When FA was administered, hepatic FA levels returned to normal levels; transaminase and lipid and protein oxidation also decreased. Its antioxidant activity was due, in part, to the modulation of superoxide dismutase activity, GSH synthesis and NOX1, NOX4 and caspase expression. FA reduced HHcy and increased the expression of coupled eNOS by increasing tetrahydrobiopterin expression, avoiding nitrosative stress. In conclusion, FA homeostasis and its antioxidant properties are affected in BD adolescent rats, making it clear that this vitamin plays an important role in the oxidative, nitrosative and apoptotic hepatic damage generated by acute ethanol exposure. For this, FA supplementation becomes a potential BD therapy for adolescents, preventing future acute alcohol-related harms.

Keywords:  apoptosis; binge drinking; folic acid; nitrosative stress; oxidative stress

DOI:  https://doi.org/10.3390/antiox11020362
Biomol Concepts. 2022 Feb 21. 13(1): 11-24

NADPH-derived ROS generation drives fibrosis and endothelial-to-mesenchymal transition in systemic sclerosis: Potential cross talk with circulating miRNAs.

Anna Maria Posadino, Gian Luca Erre, Annalisa Cossu, Costanza Emanueli, Ali H Eid, Angelo Zinellu, Gianfranco Pintus, Roberta Giordo.

  Systemic sclerosis (SSc) is an immune disorder characterized by diffuse fibrosis and vascular abnormalities of the affected organs. Although the etiopathology of this disease is largely unknown, endothelial damage and oxidative stress appear implicated in its initiation and maintenance. Here, we show for the first time that circulating factors present in SSc sera increased reactive oxygen species (ROS) production, collagen synthesis, and proliferation of human pulmonary microvascular endothelial cells (HPMECs). The observed phenomena were also associated with endothelial to mesenchymal transition (EndMT) as indicated by decreased von Willebrand factor (vWF) expression and increased alpha-smooth muscle actin, respectively, an endothelial and mesenchymal marker. SSc-induced fibroproliferative effects were prevented by HPMECs exposition to the NADPH oxidase inhibitor diphenyleneiodonium, demonstrating ROS's causative role and suggesting their cellular origin. Sera from SSc patients showed significant changes in the expression of a set of fibrosis/EndMT-associated microRNAs (miRNA), including miR-21, miR-92a, miR-24, miR-27b, miR-125b, miR-29c, and miR-181b, which resulted significantly upregulated as compared to healthy donors sera. However, miR29b resulted downregulated in SSc sera, whereas no significant differences were found in the expression of miR-29a in the two experimental groups of samples. Taking together our data indicate NADPH oxidase-induced EndMT as a potential mechanism of SSc-associated fibrosis, suggesting fibrosis-associated miRNAs as potentially responsible for initiating and sustaining the vascular alterations observed in this pathological condition.

Keywords:  EndMT; NADPH; fibrosis; miRNAs; oxidative stress; systemic sclerosis

DOI:  https://doi.org/10.1515/bmc-2021-0023
Biochem Biophys Res Commun. 2022 Feb 09. pii: S0006-291X(22)00206-6. [Epub ahead of print]600 6-13

Icariin inhibits RANKL-induced osteoclastogenesis in RAW264.7 cells via inhibition of reactive oxygen species production by reducing the expression of NOX1 and NOX4.

Ruifeng Ji, Dou Wu, Qiang Liu.

  Icariin (ICA), isolated from Herba Epimedii, is a natural flavonoid glycoside that possesses antioxidant properties and inhibits osteoclastogenesis. However, the mechanism underlying osteoclastogenesis inhibition by ICA remains unclear. Here, we investigated the effects of ICA on receptor activator of nuclear factor kappa-Β ligand (RANKL)-induced osteoclastogenesis in RAW264.7 cells. ICA inhibited the expression of osteoclastogenesis-related genes in RAW264.7 cells induced by RANKL. ICA could inhibit osteoclastogenesis without inhibiting the viability of RAW264.7 cells. In addition, ICA inhibited reactive oxygen species production in RANKL-induced RAW264.7 cells. ICA reduced the expression of nuclear factor in activated T cells, cytoplasmic 1, and tartrate-resistant acid phosphatase, which are osteoclast-related molecules. Moreover, ICA decreased the expression of nicotinamide adenine dinucleotide phosphate oxidase (NOX), specifically NOX1 and NOX4, in RANKL-induced RAW264.7 cells. Our findings suggest that ICA can be used as a potential therapeutic agent for osteolytic diseases such as osteoporosis.

Keywords:  Icariin; Osteoclastogenesis; Reactive oxygen species

DOI:  https://doi.org/10.1016/j.bbrc.2022.02.023