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Yamamuro-Tanabe A, Oshima Y, Iyama T, Ishimaru Y, Yoshioka Y. Proteasome inhibitors induce apoptosis by superoxide anion generation via NADPH oxidase 5 in human neuroblastoma SH-SY5Y cells. J Pharmacol Sci 2024; 155:52-62. [PMID: 38677786 DOI: 10.1016/j.jphs.2024.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/29/2024] [Accepted: 03/19/2024] [Indexed: 04/29/2024] Open
Abstract
The ubiquitin-proteasome system (UPS) is a major proteolytic system that plays an important role in the regulation of various cell processes, such as cell cycle, stress response, and transcriptional regulation, especially in neurons, and dysfunction of UPS is considered to be a cause of neuronal cell death in neurodegenerative diseases. However, the mechanism of neuronal cell death caused by UPS dysfunction has not yet been fully elucidated. In this study, we investigated the mechanism of neuronal cell death induced by proteasome inhibitors using human neuroblastoma SH-SY5Y cells. Z-Leu-D-Leu-Leu-al (MG132), a proteasome inhibitor, induced apoptosis in SH-SY5Y cells in a concentration- and time-dependent manner. Antioxidants N-acetylcysteine and EUK-8 attenuated MG132-induced apoptosis. Apocynin and diphenyleneiodonium, inhibitors of NADPH oxidase (NOX), an enzyme that produces superoxide anions, also attenuated MG132-induced apoptosis. It was also found that MG132 treatment increased the expression of NOX5, a NOX family member, and that siRNA-mediated silencing of NOX5 and BAPTA-AM, which inhibits NOX5 by chelating calcium, suppressed MG132-induced apoptosis and production of reactive oxygen species in SH-SY5Y cells. These results suggest that MG132 induces apoptosis in SH-SY5Y cells through the production of superoxide anion by NOX5.
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Affiliation(s)
- Akiko Yamamuro-Tanabe
- Laboratory of Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka, 573-0101, Japan
| | - Yu Oshima
- Laboratory of Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka, 573-0101, Japan
| | - Takumi Iyama
- Laboratory of Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka, 573-0101, Japan
| | - Yuki Ishimaru
- Laboratory of Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka, 573-0101, Japan
| | - Yasuhiro Yoshioka
- Laboratory of Pharmacotherapeutics, Faculty of Pharmaceutical Sciences, Setsunan University, 45-1 Nagaotoge-cho, Hirakata, Osaka, 573-0101, Japan.
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2
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Cui C, Jiang M, Jain N, Das S, Lo YH, Kermani AA, Pipatpolkai T, Sun J. Structural basis of human NOX5 activation. Nat Commun 2024; 15:3994. [PMID: 38734761 PMCID: PMC11088703 DOI: 10.1038/s41467-024-48467-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 05/02/2024] [Indexed: 05/13/2024] Open
Abstract
NADPH oxidase 5 (NOX5) catalyzes the production of superoxide free radicals and regulates physiological processes from sperm motility to cardiac rhythm. Overexpression of NOX5 leads to cancers, diabetes, and cardiovascular diseases. NOX5 is activated by intracellular calcium signaling, but the underlying molecular mechanism of which - in particular, how calcium triggers electron transfer from NADPH to FAD - is still unclear. Here we capture motions of full-length human NOX5 upon calcium binding using single-particle cryogenic electron microscopy (cryo-EM). By combining biochemistry, mutagenesis analyses, and molecular dynamics (MD) simulations, we decode the molecular basis of NOX5 activation and electron transfer. We find that calcium binding to the EF-hand domain increases NADPH dynamics, permitting electron transfer between NADPH and FAD and superoxide production. Our structural findings also uncover a zinc-binding motif that is important for NOX5 stability and enzymatic activity, revealing modulation mechanisms of reactive oxygen species (ROS) production.
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Affiliation(s)
- Chenxi Cui
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Meiqin Jiang
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Nikhil Jain
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Sourav Das
- Department of Chemical Biology & Therapeutics, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Yu-Hua Lo
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Ali A Kermani
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA
| | - Tanadet Pipatpolkai
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 673371, Singapore, Singapore.
| | - Ji Sun
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN38105, USA.
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3
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Cipriano A, Viviano M, Feoli A, Milite C, Sarno G, Castellano S, Sbardella G. NADPH Oxidases: From Molecular Mechanisms to Current Inhibitors. J Med Chem 2023; 66:11632-11655. [PMID: 37650225 PMCID: PMC10510401 DOI: 10.1021/acs.jmedchem.3c00770] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Indexed: 09/01/2023]
Abstract
NADPH oxidases (NOXs) form a family of electron-transporting membrane enzymes whose main function is reactive oxygen species (ROS) generation. Strong evidence suggests that ROS produced by NOX enzymes are major contributors to oxidative damage under pathologic conditions. Therefore, blocking the undesirable actions of these enzymes is a therapeutic strategy for treating various pathological disorders, such as cardiovascular diseases, inflammation, and cancer. To date, identification of selective NOX inhibitors is quite challenging, precluding a pharmacologic demonstration of NOX as therapeutic targets in vivo. The aim of this Perspective is to furnish an updated outlook about the small-molecule NOX inhibitors described over the last two decades. Structures, activities, and in vitro/in vivo specificity are discussed, as well as the main biological assays used.
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Affiliation(s)
- Alessandra Cipriano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Monica Viviano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Alessandra Feoli
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Ciro Milite
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Giuliana Sarno
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Sabrina Castellano
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
| | - Gianluca Sbardella
- Department
of Pharmacy, Epigenetic Med Chem Lab, and PhD Program in Drug Discovery and
Development, University of Salerno, via Giovanni Paolo II 132, I-84084 Fisciano, Salerno, Italy
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4
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Structure, regulation, and physiological functions of NADPH oxidase 5 (NOX5). J Physiol Biochem 2023:10.1007/s13105-023-00955-3. [PMID: 36905456 DOI: 10.1007/s13105-023-00955-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 03/02/2023] [Indexed: 03/12/2023]
Abstract
NOX5 is the last member of the NADPH oxidase (NOXs) family to be identified and presents some specific characteristics differing from the rest of the NOXs. It contains four Ca2+ binding domains at the N-terminus and its activity is regulated by the intracellular concentration of Ca2+. NOX5 generates superoxide (O2•-) using NADPH as a substrate, and it modulates functions related to processes in which reactive oxygen species (ROS) are involved. Those functions appear to be detrimental or beneficial depending on the level of ROS produced. For example, the increase in NOX5 activity is related to the development of various oxidative stress-related pathologies such as cancer, cardiovascular, and renal diseases. In this context, pancreatic expression of NOX5 can negatively alter insulin action in high-fat diet-fed transgenic mice. This is consistent with the idea that the expression of NOX5 tends to increase in response to a stimulus or a stressful situation, generally causing a worsening of the pathology. On the other hand, it has also been suggested that it might have a positive role in preparing the body for metabolic stress, for example, by inducing a protective adipose tissue adaptation to the excess of nutrients supplied by a high-fat diet. In this line, its endothelial overexpression can delay lipid accumulation and insulin resistance development in obese transgenic mice by inducing the secretion of IL-6 followed by the expression of thermogenic and lipolytic genes. However, as NOX5 gene is not present in rodents and human NOX5 protein has not been crystallized, its function is still poorly characterized and further extensive research is required.
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Miyano K, Kajikawa M. Ca 2+ -binding-region-dependent cell surface localization of NADPH oxidase Nox5. FEBS Lett 2023; 597:702-713. [PMID: 36653838 DOI: 10.1002/1873-3468.14577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/29/2022] [Accepted: 01/08/2023] [Indexed: 01/20/2023]
Abstract
Six gene splice variants of superoxide-generating NADPH oxidase 5 (Nox5) have been identified in humans, and they differ in the sequence of their N-terminal cytoplasmic domains, which comprise four EF-hand motifs. Here, we demonstrated that the Ca2+ -dependent association and dissociation between the N- and C-terminal cytoplasmic domains of the Nox5β variant are affected by the alanine substitution of the conserved Ile-113 or Leu-115 at the connecting loop between the third and fourth EF-hand motifs. These substitutions impair the cell surface localization of Nox5β. In addition, the Nox5ε/S variant, lacking all EF-hand motifs, does not localize to the plasma membrane. Thus, the Ca2+ -sensitive intramolecular interaction determines the Nox5 subcellular localization, that is, whether Nox5 variants generate superoxide in the extracellular or intracellular space.
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Affiliation(s)
- Kei Miyano
- Department of Natural Sciences, Kawasaki Medical School, Okayama, Japan
- Department of Biochemistry, Kawasaki Medical School, Okayama, Japan
| | - Mizuho Kajikawa
- Laboratory of Microbiology, Showa Pharmaceutical University, Tokyo, Japan
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6
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Ogboo BC, Grabovyy UV, Maini A, Scouten S, van der Vliet A, Mattevi A, Heppner DE. Architecture of the NADPH oxidase family of enzymes. Redox Biol 2022; 52:102298. [PMID: 35334249 PMCID: PMC8956913 DOI: 10.1016/j.redox.2022.102298] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/16/2022] [Accepted: 03/16/2022] [Indexed: 12/11/2022] Open
Abstract
The NADPH Oxidases (NOX) catalyze the deliberate production of reactive oxygen species (ROS) and are established regulators of redox-dependent processes across diverse biological settings. Proper management of their activity is controlled through a conserved electron transfer (ET) cascade from cytosolic NADPH substrate through the plasma membrane to extracellular O2. After decades-long investigations of their biological functions, including potential as drug targets, only very recently has atomic-resolution information of NOX enzymes been made available. In this graphical review, we summarize the present structural biology understanding of the NOX enzymes afforded by X-ray crystallography and cryo-electron microscopy. Combined molecular-level insights predominantly informed by DUOX1 full-length Cryo-EM structures suggest a general structural basis for the control of their catalytic activity by intracellular domain-domain stabilization.
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Affiliation(s)
- Blessing C Ogboo
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Uriy V Grabovyy
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Aniket Maini
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Scott Scouten
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY, USA
| | - Albert van der Vliet
- Department of Pathology and Laboratory Medicine, Robert Larner, M.D. College of Medicine, University of Vermont, Burlington, VT, USA
| | - Andrea Mattevi
- Department of Genetics and Microbiology, University of Pavia, Italy
| | - David E Heppner
- Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY, USA; Department of Pharmacology and Therapeutics, Roswell Park Comprehensive Cancer Center, Buffalo, NY, USA.
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Lysophosphatidylcholine induces oxidative stress in human endothelial cells via NOX5 activation - implications in atherosclerosis. Clin Sci (Lond) 2021; 135:1845-1858. [PMID: 34269800 DOI: 10.1042/cs20210468] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/02/2021] [Accepted: 07/16/2021] [Indexed: 02/01/2023]
Abstract
OBJECTIVE The mechanisms involved in NOX5 activation in atherosclerotic processes are not completely understood. This study tested the hypothesis that lysophosphatidylcholine (LPC), a proatherogenic component of oxLDL, induces endothelial calcium influx, which drives NOX5-dependent reactive oxygen species (ROS) production, oxidative stress, and endothelial cell dysfunction. Approach: Human aortic endothelial cells (HAEC) were stimulated with LPC (10-5 M, for different time points). Pharmacological inhibition of NOX5 (Melittin, 10-7 M) and NOX5 gene silencing (siRNA) were used to determine the role of NOX5-dependent ROS production in endothelial oxidative stress induced by LPC. ROS production was determined by lucigenin assay and electron paramagnetic spectroscopy (EPR), calcium transients by Fluo4 fluorimetry, and NOX5 activity and protein expression by pharmacological assays and immunoblotting, respectively. RESULTS LPC increased ROS generation in endothelial cells at short (15 min) and long (4 h) stimulation times. LPC-induced ROS was abolished by a selective NOX5 inhibitor and by NOX5 siRNA. NOX1/4 dual inhibition and selective NOX1 inhibition only decreased ROS generation at 4 h. LPC increased HAEC intracellular calcium, important for NOX5 activation, and this was blocked by nifedipine and thapsigargin. Bapta-AM, selective Ca2+ chelator, prevented LPC-induced ROS production. NOX5 knockdown decreased LPC-induced ICAM-1 mRNA expression and monocyte adhesion to endothelial cells. CONCLUSION These results suggest that NOX5, by mechanisms linked to increased intracellular calcium, is key to early LPC-induced endothelial oxidative stress and pro-inflammatory processes. Since these are essential events in the formation and progression of atherosclerotic lesions, this study highlights an important role for NOX5 in atherosclerosis.
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8
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Wang J, Xiao J, Meng X, Chu X, Zhuansun DD, Xiong B, Feng J. NOX5 is expressed aberrantly but not a critical pathogenetic gene in Hirschsprung disease. BMC Pediatr 2021; 21:153. [PMID: 33784990 PMCID: PMC8008622 DOI: 10.1186/s12887-021-02611-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 03/11/2021] [Indexed: 01/11/2023] Open
Abstract
Background Hirschsprung disease (HSCR) is a congenital disorder characterized by the absence of intramural ganglion cells in the distal gastrointestinal tract (GI), which results in tonic contraction of the aganglionic gut segment and functional intestinal obstruction. Recent studies have suggested NADPH oxidase 5 (NOX5) as a candidate risk gene for HSCR. In this study, we examined the function of NOX5 to verify its role in the development of the enteric nervous system (ENS). Methods HSCR tissue specimens (n = 10) were collected at the time of pull-through surgery and control specimens (n = 10) were obtained at the time of colostomy closure in patients. The NOX5 expression in aganglionic and ganglionic segments of HSCR colon and normal colon were analyzed by immunohistochemistry (IHC), western blot and real-time quantitative PCR (qPCR). The gene expression levels and spatiotemporal expression spectrum of NOX5 in different development stages of zebrafish embryo were determined using qPCR and in-situ hybridization (ISH). The enteric nervous system in NOX5 Morpholino (MO) knockdown and wild type (WT) zebrafish embryo was analyzed by whole-mount immunofluorescence (IF). Intestinal transit assay was performed to analyze the gastrointestinal motility in NOX5 knockdown and control larvae. Results NOX5 is strongly expressed in the ganglion cells in the proximal segment of HSCR colons and all segments of normal colons. Moreover, the expression of NOX5 is markedly decreased in the aganglionic segment of HSCR colon compared to the ganglionic segment. In zebrafish, NOX5 mRNA level is the highest in the one cell stage embryos and it is decreased overtime with the development of the embryos. Interestingly, the expression of NOX5 appears to be enriched in the nervous system. However, the number of neurons in the GI tract and the GI motility were not affected upon NOX5 knockdown. Conclusions Our study shows that NOX5 markedly decreased in the aganglionic segment of HSCR but didn’t involve in the ENS development of zebrafish. It implies that absence of intestinal ganglion cells may lead to down-regulation of NOX5. Supplementary Information The online version contains supplementary material available at 10.1186/s12887-021-02611-5.
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Affiliation(s)
- Jing Wang
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China
| | - Jun Xiao
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China
| | - Xinyao Meng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China
| | - Xufeng Chu
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Hangkong road, Baofeng street, Qiaokou district, Wuhan, 430030, China
| | - Di Di Zhuansun
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China
| | - Bo Xiong
- Department of Forensic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Hangkong road, Baofeng street, Qiaokou district, Wuhan, 430030, China.
| | - Jiexiong Feng
- Department of Pediatric Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1095 Jiefang Ave, Wuhan, 430030, China.
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Abstract
Significance: The primary function of NADPH oxidases (NOX1-5 and dual oxidases DUOX1/2) is to produce reactive oxygen species (ROS). If inadequately regulated, NOX-associated ROS can promote oxidative stress, aberrant signaling, and genomic instability. Correspondingly, NOX isoforms are known to be overexpressed in multiple malignancies, thus constituting potential therapeutic targets in cancer. Recent Advances: Multiple genetic studies aimed at suppressing the expression of NOX proteins in cellular and animal models of cancer have provided support for the notion that NOXs play a pro-tumorigenic role. Further, large drug screens and rational design efforts have yielded inhibitor compounds, such as the diphenylene iodonium (DPI) analog series developed by our group, with increased selectivity and potency over "first generation" NOX inhibitors such as apocynin and DPI. Critical Issues: The precise role of NOX enzymes in tumor biology remains poorly defined. The tumorigenic properties of NOXs vary with cancer type, and precise tools, such as selective inhibitors, are needed to deconvolute NOX contribution to cancer development. Most NOX inhibitors developed to date are unspecific, and/or their mechanistic and pharmacological characteristics are not well defined. A lack of high-resolution crystal structures for NOX functional domains has hindered the development of potent and selective inhibitors. Future Directions: In-depth studies of NOX interactions with the tumor microenvironment (e.g., cytokines, cell-surface antigens) will help identify new approaches for NOX inhibition in cancer.
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Affiliation(s)
- Mariam M Konaté
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - Smitha Antony
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, NIH, Bethesda, Maryland, USA
| | - James H Doroshow
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, NIH, Bethesda, Maryland, USA.,Developmental Therapeutics Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland, USA
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Membranous NOX5-derived ROS oxidizes and activates local Src to promote malignancy of tumor cells. Signal Transduct Target Ther 2020; 5:139. [PMID: 32792487 PMCID: PMC7426961 DOI: 10.1038/s41392-020-0193-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 05/01/2020] [Accepted: 05/08/2020] [Indexed: 01/18/2023] Open
Abstract
Reactive oxygen species (ROS) localized at the precise subcellular compartments are essential for regulating the activity of signaling proteins. Furthermore, ROS are master regulators of tumor malignant progression that respond to a diverse set of environmental stress, especially hypoxia. NADPH oxidases (NOXs) appear to be activated within discrete subcellular compartments to facilitate local ROS production. However, the subcellular function of NOXs in hypoxic tumor is still unclear. In this study, we demonstrated that NOX5 was greatly upregulated in clinical esophageal squamous cell carcinoma (ESCC) tumors, ESCC cell lines or primary ESCC cells, and elevated NOX5 was correlated to malignancy of ESCC tumors and poor prognosis. NOX5 induced the malignant progression of ESCC by activating Src, especially under hypoxic condition. Mechanistically, we showed that hypoxia promoted the interaction between NOX5 and Pyk2 on cell membrane via facilitating Ca2+-mediated Pyk2 Tyr402 site phosphorylation. Subsequently, Pyk2 acted as a scaffold for c-Abl phosphorylating the catalytic domain of NOX5 Tyr476/478 sites, which in turn upregulated hydrogen peroxide (H2O2) inside the Pyk2/NOX5 complex to oxidize and activate local Src. These findings provide insights into the biological significance of NOX5 in the development of ESCC.
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11
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Sweeny EA, Schlanger S, Stuehr DJ. Dynamic regulation of NADPH oxidase 5 by intracellular heme levels and cellular chaperones. Redox Biol 2020; 36:101656. [PMID: 32738790 PMCID: PMC7394750 DOI: 10.1016/j.redox.2020.101656] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/13/2020] [Accepted: 07/21/2020] [Indexed: 12/15/2022] Open
Abstract
NADPH oxidase 5 (NOX5) is a transmembrane signaling enzyme that produces superoxide in response to elevated cytosolic calcium. In addition to its association with numerous human diseases, NOX5 has recently been discovered to play crucial roles in the immune response and cardiovascular system. Details of NOX5 maturation, and specifically its response to changes in intracellular heme levels have remained unclear. Here we establish an experimental system in mammalian cells that allows us to probe the influence of heme availability on ROS production by NOX5. We identified a mode of dynamic regulatory control over NOX5 activity through modulation of its heme saturation and oligomeric state by intracellular heme levels and Hsp90 binding. This regulatory mechanism allows for fine-tuning and reversible modulation of NOX5 activity in response to stimuli.
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Affiliation(s)
- Elizabeth A Sweeny
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA.
| | - Simon Schlanger
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA
| | - Dennis J Stuehr
- Department of Inflammation and Immunity, Lerner Research Institute, The Cleveland Clinic, Cleveland, OH, 44195, USA.
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12
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Millana Fañanás E, Todesca S, Sicorello A, Masino L, Pompach P, Magnani F, Pastore A, Mattevi A. On the mechanism of calcium-dependent activation of NADPH oxidase 5 (NOX5). FEBS J 2020; 287:2486-2503. [PMID: 31785178 PMCID: PMC7317449 DOI: 10.1111/febs.15160] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/27/2019] [Indexed: 12/15/2022]
Abstract
It is now accepted that reactive oxygen species (ROS) are not only dangerous oxidative agents but also chemical mediators of the redox cell signaling and innate immune response. A central role in ROS-controlled production is played by the NADPH oxidases (NOXs), a group of seven membrane-bound enzymes (NOX1-5 and DUOX1-2) whose unique function is to produce ROS. Here, we describe the regulation of NOX5, a widespread family member present in cyanobacteria, protists, plants, fungi, and the animal kingdom. We show that the calmodulin-like regulatory EF-domain of NOX5 is partially unfolded and detached from the rest of the protein in the absence of calcium. In the presence of calcium, the C-terminal lobe of the EF-domain acquires an ordered and more compact structure that enables its binding to the enzyme dehydrogenase (DH) domain. Our spectroscopic and mutagenesis studies further identified a set of conserved aspartate residues in the DH domain that are essential for NOX5 activation. Altogether, our work shows that calcium induces an unfolded-to-folded transition of the EF-domain that promotes direct interaction with a conserved regulatory region, resulting in NOX5 activation.
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Affiliation(s)
- Elisa Millana Fañanás
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Sofia Todesca
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Alessandro Sicorello
- UK Dementia Research Institute at King's College LondonUK
- The Wohl Institute at King's College LondonUK
| | | | - Petr Pompach
- Institute of BiotechnologyCzech Academy of SciencesVestecCzech Republic
- Institute of MicrobiologyCzech Academy of SciencesPragueCzech Republic
| | - Francesca Magnani
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
| | - Annalisa Pastore
- UK Dementia Research Institute at King's College LondonUK
- The Wohl Institute at King's College LondonUK
| | - Andrea Mattevi
- Department of Biology and Biotechnology “Lazzaro Spallanzani”University of PaviaItaly
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13
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Schröder K. NADPH oxidases: Current aspects and tools. Redox Biol 2020; 34:101512. [PMID: 32480354 PMCID: PMC7262010 DOI: 10.1016/j.redox.2020.101512] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 03/11/2020] [Accepted: 03/16/2020] [Indexed: 12/27/2022] Open
Abstract
Reactive oxygen species (ROS) have been shown or at least suggested to play an essential role for cellular signaling as second messengers. NADPH oxidases represent a source of controlled ROS formation. Accordingly, understanding the role of individual NADPH oxidases bears potential to interfere with intracellular signaling cascades without disturbing the signaling itself. Many tools have been developed to study or inhibit the functions and roles of the NADPH oxidases. This short review summarizes diseases, potentially associated with NADPH oxidases, genetically modified animals, and inhibitors.
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Affiliation(s)
- Katrin Schröder
- Institut für Kardiovaskuläre Physiologie, Fachbereich Medizin der Goethe-Universität, Theodor-Stern Kai 7, 60590, Frankfurt, Germany. https://
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Wei CC, Hay E, Smith D, Lloyd L, Acharya G, Ngo R. Binding of Nox5's EF-Hand domain to the peptides corresponding to the phosphorylatable region and regulatory inhibitory loop in its dehydrogenase domain. Biophys Chem 2020; 262:106379. [PMID: 32339785 DOI: 10.1016/j.bpc.2020.106379] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/21/2020] [Accepted: 04/13/2020] [Indexed: 12/13/2022]
Abstract
Reactive oxygen species (ROS) produced by NADPH oxidase 5 (Nox5) are regulated by Ca2+ flux through the interactions of its self-contained EF-hand domain (EFD), dehydrogenase domain (DH), and transmembrane domain. Studies suggest that the regulatory EF-hand binding domain (REFBD) and phosphorylatable (PhosR) sequences within DH play an important role in Nox5's superoxide-generating activity. However, the interplay of the EFD-DH interaction is largely unclear. Here, we used two synthetic peptides corresponding to the putative REFBD and PhosR sequences, as well as DH construct proteins, and separately studied their binding to EFD by fluorescence spectroscopy and calorimetry. With mutagenesis, we revealed that the C-terminal half domain of EFD binds specifically to REFBD in a Ca2+-dependent manner, which is driven primarily by hydrophobic interactions to form a more compact structure. On the other hand, the interaction between EFD and PhosR is not Ca2+-dependent and is primarily dominated by electrostatic interactions. The binding constants (Ka) for both peptides to EFD were calculated to be in the range of 105 M-1. The formation of the binary complex EFD/REFBD and ternary complex EFD/REFBD/PhosR was demonstrated by fluorescence resonance energy transfer (FRET). However, EFD binding to PhosR appears to be not biologically important while the conformational change on its C-terminal half domain resembles a major factor in EFD-DH domain-domain interactions.
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Affiliation(s)
- Chin-Chuan Wei
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA; Department of Pharmaceutical Sciences, College of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA.
| | - Evan Hay
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Dustin Smith
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Laura Lloyd
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Ganesh Acharya
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Rebecca Ngo
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
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15
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Aliniaeifard S, Shomali A, Seifikalhor M, Lastochkina O. Calcium Signaling in Plants Under Drought. SALT AND DROUGHT STRESS TOLERANCE IN PLANTS 2020:259-298. [DOI: 10.1007/978-3-030-40277-8_10] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/23/2023]
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16
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Knock GA. NADPH oxidase in the vasculature: Expression, regulation and signalling pathways; role in normal cardiovascular physiology and its dysregulation in hypertension. Free Radic Biol Med 2019; 145:385-427. [PMID: 31585207 DOI: 10.1016/j.freeradbiomed.2019.09.029] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/29/2019] [Accepted: 09/23/2019] [Indexed: 02/06/2023]
Abstract
The last 20-25 years have seen an explosion of interest in the role of NADPH oxidase (NOX) in cardiovascular function and disease. In vascular smooth muscle and endothelium, NOX generates reactive oxygen species (ROS) that act as second messengers, contributing to the control of normal vascular function. NOX activity is altered in response to a variety of stimuli, including G-protein coupled receptor agonists, growth-factors, perfusion pressure, flow and hypoxia. NOX-derived ROS are involved in smooth muscle constriction, endothelium-dependent relaxation and smooth muscle growth, proliferation and migration, thus contributing to the fine-tuning of blood flow, arterial wall thickness and vascular resistance. Through reversible oxidative modification of target proteins, ROS regulate the activity of protein tyrosine phosphatases, kinases, G proteins, ion channels, cytoskeletal proteins and transcription factors. There is now considerable, but somewhat contradictory evidence that NOX contributes to the pathogenesis of hypertension through oxidative stress. Specific NOX isoforms have been implicated in endothelial dysfunction, hyper-contractility and vascular remodelling in various animal models of hypertension, pulmonary hypertension and pulmonary arterial hypertension, but also have potential protective effects, particularly NOX4. This review explores the multiplicity of NOX function in the healthy vasculature and the evidence for and against targeting NOX for antihypertensive therapy.
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Affiliation(s)
- Greg A Knock
- Dpt. of Inflammation Biology, School of Immunology & Microbial Sciences, Faculty of Life Sciences & Medicine, King's College London, UK.
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17
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Zemskov EA, Lu Q, Ornatowski W, Klinger CN, Desai AA, Maltepe E, Yuan JXJ, Wang T, Fineman JR, Black SM. Biomechanical Forces and Oxidative Stress: Implications for Pulmonary Vascular Disease. Antioxid Redox Signal 2019; 31:819-842. [PMID: 30623676 PMCID: PMC6751394 DOI: 10.1089/ars.2018.7720] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Significance: Oxidative stress in the cell is characterized by excessive generation of reactive oxygen species (ROS). Superoxide (O2-) and hydrogen peroxide (H2O2) are the main ROS involved in the regulation of cellular metabolism. As our fundamental understanding of the underlying causes of lung disease has increased it has become evident that oxidative stress plays a critical role. Recent Advances: A number of cells in the lung both produce, and respond to, ROS. These include vascular endothelial and smooth muscle cells, fibroblasts, and epithelial cells as well as the cells involved in the inflammatory response, including macrophages, neutrophils, eosinophils. The redox system is involved in multiple aspects of cell metabolism and cell homeostasis. Critical Issues: Dysregulation of the cellular redox system has consequential effects on cell signaling pathways that are intimately involved in disease progression. The lung is exposed to biomechanical forces (fluid shear stress, cyclic stretch, and pressure) due to the passage of blood through the pulmonary vessels and the distension of the lungs during the breathing cycle. Cells within the lung respond to these forces by activating signal transduction pathways that alter their redox state with both physiologic and pathologic consequences. Future Directions: Here, we will discuss the intimate relationship between biomechanical forces and redox signaling and its role in the development of pulmonary disease. An understanding of the molecular mechanisms induced by biomechanical forces in the pulmonary vasculature is necessary for the development of new therapeutic strategies.
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Affiliation(s)
- Evgeny A Zemskov
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Qing Lu
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Wojciech Ornatowski
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Christina N Klinger
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Ankit A Desai
- Department of Medicine, Indiana University, Indianapolis, Indiana
| | - Emin Maltepe
- Department of Pediatrics, University of California, San Francisco, San Francisco, California
| | - Jason X-J Yuan
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
| | - Ting Wang
- Department of Internal Medicine, The University of Arizona Health Sciences, Phoenix, Arizona
| | - Jeffrey R Fineman
- Department of Pediatrics, University of California, San Francisco, San Francisco, California
| | - Stephen M Black
- Department of Medicine, The University of Arizona Health Sciences, Tucson, Arizona
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18
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Jha JC, Dai A, Holterman CE, Cooper ME, Touyz RM, Kennedy CR, Jandeleit-Dahm KAM. Endothelial or vascular smooth muscle cell-specific expression of human NOX5 exacerbates renal inflammation, fibrosis and albuminuria in the Akita mouse. Diabetologia 2019; 62:1712-1726. [PMID: 31222503 DOI: 10.1007/s00125-019-4924-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/10/2019] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS Excessive production of reactive oxygen species (ROS) plays a detrimental role in the progression of diabetic kidney disease (DKD). Renal oxidative stress activates proinflammatory cytokines, chemokines and profibrotic factors in DKD. Increased expression of the prooxidant enzyme NADPH oxidase (NOX) 5 in kidneys of diabetic individuals has been hypothesised to correlate with renal injury and progression of DKD. Since the gene encoding NOX5 is not expressed in the mouse genome, we examined the effect of inducible human NOX5 expression in renal cells, selectively in either endothelial cells or vascular smooth muscle cells (VSMCs)/mesangial cells in a model of insulin-deficient diabetes, the Akita mouse. METHODS Renal structural injury, including glomerulosclerosis, mesangial expansion and extracellular matrix protein accumulation, as well as renal inflammation, ROS formation and albuminuria, were examined in the NOX5 transgenic Akita mouse model of DKD. RESULTS Expression of NOX5 in either endothelial cells or VSMCs/mesangial cells in diabetic Akita mice was associated with increased renal inflammation (monocyte chemoattractant protein-1, NF-κB and toll-like receptor-4) and glomerulosclerosis, as well as upregulation of protein kinase C-α and increased expression of extracellular matrix genes (encoding collagen III, fibronectin and α-smooth muscle actin) and proteins (collagen IV), most likely mediated via enhanced renal ROS production. The effect of VSMC/mesangial cell-specific NOX5 expression resulted in more pronounced renal fibrosis in comparison with endothelial cell-specific NOX5 expression in diabetic mice. In addition, albuminuria was significantly increased in diabetic VEcad+NOX5+ mice (1192 ± 194 μg/24 h) when compared with diabetic VEcad+NOX5- mice (770 ± 98 μg/24 h). Furthermore, the regulatory components of NOX5 activation, including heat shock protein 90 and transient receptor potential cation channel subfamily C member 6, were upregulated only in the presence of both NOX5 and diabetes. CONCLUSIONS/INTERPRETATION The findings from this study highlight the importance of NOX5 in promoting diabetes-related renal injury and provide the rationale for the development of a selective NOX5 inhibitor for the prevention and/or treatment of DKD.
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Affiliation(s)
- Jay C Jha
- Department of Diabetes, Central Clinical School, Monash University, 99 Commercial Road, Level 5, Melbourne, VIC, 3004, Australia
| | - Aozhi Dai
- Department of Diabetes, Central Clinical School, Monash University, 99 Commercial Road, Level 5, Melbourne, VIC, 3004, Australia
| | - Chet E Holterman
- Department of Medicine, Kidney Research Centre, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Mark E Cooper
- Department of Diabetes, Central Clinical School, Monash University, 99 Commercial Road, Level 5, Melbourne, VIC, 3004, Australia
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Chris R Kennedy
- Department of Medicine, Kidney Research Centre, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Karin A M Jandeleit-Dahm
- Department of Diabetes, Central Clinical School, Monash University, 99 Commercial Road, Level 5, Melbourne, VIC, 3004, Australia.
- German Diabetes Centre, Institute for Clinical Diabetology, Leibniz Centre for Diabetes Research, Heinrich-Heine University, Duesseldorf, Germany.
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19
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Wei CC, Fabry E, Hay E, Lloyd L, Kaufman N, Yang YP, Stuehr DJ. Metal binding and conformational studies of the calcium binding domain of NADPH oxidase 5 reveal its similarity and difference to calmodulin. J Biomol Struct Dyn 2019; 38:2352-2368. [DOI: 10.1080/07391102.2019.1633409] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Chin-Chuan Wei
- Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, Illinois, USA
| | - Emily Fabry
- Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, Illinois, USA
| | - Evan Hay
- Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, Illinois, USA
| | - Laura Lloyd
- Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, Illinois, USA
| | - Nichole Kaufman
- Department of Chemistry, Southern Illinois University Edwardsville, Edwardsville, Illinois, USA
| | - Ya-Ping Yang
- Department of Pathobiology, the Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
| | - Dennis J. Stuehr
- Department of Pathobiology, the Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, USA
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20
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Touyz RM, Anagnostopoulou A, Rios F, Montezano AC, Camargo LL. NOX5: Molecular biology and pathophysiology. Exp Physiol 2019; 104:605-616. [PMID: 30801870 PMCID: PMC6519284 DOI: 10.1113/ep086204] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 02/20/2019] [Indexed: 12/12/2022]
Abstract
NEW FINDINGS What is the topic of this review? This review provides a comprehensive overview of Nox5 from basic biology to human disease and highlights unique features of this Nox isoform What advances does it highlight? Major advances in Nox5 biology relate to crystallization of the molecule and new insights into the pathophysiological role of Nox5. Recent discoveries have unravelled the crystal structure of Nox5, the first Nox isoform to be crystalized. This provides new opportunities to develop drugs or small molecules targeted to Nox5 in an isoform-specific manner, possibly for therapeutic use. Moreover genome wide association studies (GWAS) identified Nox5 as a new blood pressure-associated gene and studies in mice expressing human Nox5 in a cell-specific manner have provided new information about the (patho) physiological role of Nox5 in the cardiovascular system and kidneys. Nox5 seems to be important in the regulation of vascular contraction and kidney function. In cardiovascular disease and diabetic nephropathy, Nox5 activity is increased and this is associated with increased production of reactive oxygen species and oxidative stress implicated in tissue damage. ABSTRACT Nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (Nox), comprise seven family members (Nox1-Nox5 and dual oxidase 1 and 2) and are major producers of reactive oxygen species in mammalian cells. Reactive oxygen species are crucially involved in cell signalling and function. All Noxs share structural homology comprising six transmembrane domains with two haem-binding regions and an NADPH-binding region on the intracellular C-terminus, whereas their regulatory systems, mechanisms of activation and tissue distribution differ. This explains the diverse function of Noxs. Of the Noxs, NOX5 is unique in that rodents lack the gene, it is regulated by Ca2+ , it does not require NADPH oxidase subunits for its activation, and it is not glycosylated. NOX5 localizes in the perinuclear and endoplasmic reticulum regions of cells and traffics to the cell membrane upon activation. It is tightly regulated through numerous post-translational modifications and is activated by vasoactive agents, growth factors and pro-inflammatory cytokines. The exact pathophysiological significance of NOX5 remains unclear, but it seems to be important in the physiological regulation of sperm motility, vascular contraction and lymphocyte differentiation, and NOX5 hyperactivation has been implicated in cardiovascular disease, kidney injury and cancer. The field of NOX5 biology is still in its infancy, but with new insights into its biochemistry and cellular regulation, discovery of the NOX5 crystal structure and genome-wide association studies implicating NOX5 in disease, the time is now ripe to advance NOX5 research. This review provides a comprehensive overview of our current understanding of NOX5, from basic biology to human disease, and highlights the unique characteristics of this enigmatic Nox isoform.
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Affiliation(s)
- Rhian M. Touyz
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular CentreUniversity of GlasgowGlasgowUK
| | - Aikaterini Anagnostopoulou
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular CentreUniversity of GlasgowGlasgowUK
| | - Francisco Rios
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular CentreUniversity of GlasgowGlasgowUK
| | - Augusto C. Montezano
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular CentreUniversity of GlasgowGlasgowUK
| | - Livia L. Camargo
- Institute of Cardiovascular and Medical SciencesBHF Glasgow Cardiovascular CentreUniversity of GlasgowGlasgowUK
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21
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Tejero J, Shiva S, Gladwin MT. Sources of Vascular Nitric Oxide and Reactive Oxygen Species and Their Regulation. Physiol Rev 2019; 99:311-379. [PMID: 30379623 DOI: 10.1152/physrev.00036.2017] [Citation(s) in RCA: 271] [Impact Index Per Article: 54.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Nitric oxide (NO) is a small free radical with critical signaling roles in physiology and pathophysiology. The generation of sufficient NO levels to regulate the resistance of the blood vessels and hence the maintenance of adequate blood flow is critical to the healthy performance of the vasculature. A novel paradigm indicates that classical NO synthesis by dedicated NO synthases is supplemented by nitrite reduction pathways under hypoxia. At the same time, reactive oxygen species (ROS), which include superoxide and hydrogen peroxide, are produced in the vascular system for signaling purposes, as effectors of the immune response, or as byproducts of cellular metabolism. NO and ROS can be generated by distinct enzymes or by the same enzyme through alternate reduction and oxidation processes. The latter oxidoreductase systems include NO synthases, molybdopterin enzymes, and hemoglobins, which can form superoxide by reduction of molecular oxygen or NO by reduction of inorganic nitrite. Enzymatic uncoupling, changes in oxygen tension, and the concentration of coenzymes and reductants can modulate the NO/ROS production from these oxidoreductases and determine the redox balance in health and disease. The dysregulation of the mechanisms involved in the generation of NO and ROS is an important cause of cardiovascular disease and target for therapy. In this review we will present the biology of NO and ROS in the cardiovascular system, with special emphasis on their routes of formation and regulation, as well as the therapeutic challenges and opportunities for the management of NO and ROS in cardiovascular disease.
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Affiliation(s)
- Jesús Tejero
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh , Pittsburgh, Pennsylvania ; Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania ; Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, Pennsylvania ; and Department of Medicine, Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Sruti Shiva
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh , Pittsburgh, Pennsylvania ; Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania ; Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, Pennsylvania ; and Department of Medicine, Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
| | - Mark T Gladwin
- Pittsburgh Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh , Pittsburgh, Pennsylvania ; Pulmonary, Allergy and Critical Care Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania ; Department of Pharmacology and Chemical Biology, University of Pittsburgh , Pittsburgh, Pennsylvania ; and Department of Medicine, Center for Metabolism and Mitochondrial Medicine, University of Pittsburgh , Pittsburgh, Pennsylvania
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22
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Abstract
NOX (NADPH oxidases) are a family of NADPH-dependent transmembrane enzymes that synthesize superoxide and other reactive oxygen species. There are seven isoforms (NOX1-5 and DUOX1-2) which derive from a common ancestral NOX. NOX enzymes are distinguished by different modes of activation, the types of ROS that are produced, the cell types where they are expressed, and distinct functional roles. NOX5 was one of the earliest eukaryotic Nox enzymes to evolve and ironically the last isoform to be discovered in humans. In the time since its discovery, our knowledge of the regulation of NOX5 has expanded tremendously, and we now have a more comprehensive understanding of the molecular mechanisms underlying NOX5-dependent ROS production. In contrast, the cell types where NOX5 is robustly expressed and its functional significance in health and disease remain an underdeveloped area. The goal of this chapter is to provide an up-to-date overview of the mechanisms regulating NOX5 function and its importance in human physiology and pathophysiology.
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Affiliation(s)
- David J R Fulton
- Vascular Biology Center, Medical College of Georgia at Augusta University, Augusta, GA, USA.
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23
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Rudolf J, Raad H, Taieb A, Rezvani HR. NADPH Oxidases and Their Roles in Skin Homeostasis and Carcinogenesis. Antioxid Redox Signal 2018; 28:1238-1261. [PMID: 28990413 DOI: 10.1089/ars.2017.7282] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
SIGNIFICANCE Skin protects the body from dehydration, pathogens, and external mutagens. NADPH oxidases are central components for regulating the cellular redox balance. There is increasing evidence indicating that reactive oxygen species (ROS) generated by members of this enzyme family play important roles in the physiology and pathophysiology of the skin. Recent Advances: NADPH oxidases are active producers of ROS such as superoxide and hydrogen peroxide. Different isoforms are found in virtually all tissues. They play pivotal roles in normal cell homeostasis and in the cellular responses to various stressors. In particular, these enzymes are integral parts of redox-sensitive prosurvival and proapoptotic signaling pathways, in which they act both as effectors and as modulators. However, continuous (re)activation of NADPH oxidases can disturb the redox balance of cells, in the worst-case scenario in a permanent manner. Abnormal NADPH oxidase activity has been associated with a wide spectrum of diseases, as well as with aging and carcinogenesis. CRITICAL ISSUES Sunlight with its beneficial and deleterious effects induces the activation of NADPH oxidases in the skin. Evidence for the important roles of this enzyme family in skin cancer and skin aging, as well as in many chronic skin diseases, is now emerging. FUTURE DIRECTIONS Understanding the precise roles of NADPH oxidases in normal skin homeostasis, in the cellular responses to solar radiation, and during carcinogenesis will pave the way for their validation as therapeutic targets not only for the prevention and treatment of skin cancers but also for many other skin-related disorders. Antioxid. Redox Signal. 28, 1238-1261.
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Affiliation(s)
- Jana Rudolf
- 1 Inserm U 1035, Bordeaux, France .,2 Université de Bordeaux , Bordeaux, France
| | - Houssam Raad
- 1 Inserm U 1035, Bordeaux, France .,2 Université de Bordeaux , Bordeaux, France
| | - Alain Taieb
- 1 Inserm U 1035, Bordeaux, France .,2 Université de Bordeaux , Bordeaux, France .,3 Service de Dermatologie Adulte et Pédiatrique , CHU de Bordeaux, Bordeaux, France .,4 Centre de Référence des Maladies Rares de la Peau , CHU de Bordeaux, Bordeaux, France
| | - Hamid Reza Rezvani
- 1 Inserm U 1035, Bordeaux, France .,2 Université de Bordeaux , Bordeaux, France .,4 Centre de Référence des Maladies Rares de la Peau , CHU de Bordeaux, Bordeaux, France
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24
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Demidchik V, Shabala S. Mechanisms of cytosolic calcium elevation in plants: the role of ion channels, calcium extrusion systems and NADPH oxidase-mediated 'ROS-Ca 2+ Hub'. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:9-27. [PMID: 32291018 DOI: 10.1071/fp16420] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/07/2016] [Indexed: 05/22/2023]
Abstract
Elevation in the cytosolic free calcium is crucial for plant growth, development and adaptation. Calcium influx into plant cells is mediated by Ca2+ depolarisation-activated, hyperpolarisation-activated and voltage-independent Ca2+-permeable channels (DACCs, HACCs and VICCs respectively). These channels are encoded by the following gene families: (1) cyclic nucleotide-gated channels (CNGCs), (2) ionotropic glutamate receptors (GLRs), (3) annexins, (4) 'mechanosensitive channels of small (MscS) conductance'-like channels (MSLs), (5) 'mid1-complementing activity' channels (MCAs), Piezo channels, and hyperosmolality-induced [Ca2+]cyt. channel 1 (OSCA1). Also, a 'tandem-pore channel1' (TPC1) catalyses Ca2+ efflux from the vacuole in response to the plasma membrane-mediated Ca2+ elevation. Recent experimental data demonstrated that Arabidopsis thaliana (L.) Heynh. CNGCs 2, 5-10, 14, 16 and 18, GLRs 1.2, 3.3, 3.4, 3.6 and 3.7, TPC1, ANNEXIN1, MSL9 and MSL10,MCA1 and MCA2, OSCA1, and some their homologues counterparts in other species, are responsible for Ca2+ currents and/or cytosolic Ca2+ elevation. Extrusion of Ca2+ from the cytosol is mediated by Ca2+-ATPases and Ca2+/H+ exchangers which were recently examined at the level of high resolution crystal structure. Calcium-activated NADPH oxidases and reactive oxygen species (ROS)-activated Ca2+ conductances form a self-amplifying 'ROS-Ca2+hub', enhancing and transducing Ca2+ and redox signals. The ROS-Ca2+ hub contributes to physiological reactions controlled by ROS and Ca2+, demonstrating synergism and unity of Ca2+ and ROS signalling mechanisms.
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Affiliation(s)
- Vadim Demidchik
- Department of Plant Cell Biology and Bioengineering, Biological Faculty, Belarusian State University, 4 Independence Avenue, Minsk, 220030, Belarus
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag 54, Hobart, Tas. 7001, Australia
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25
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Beaumel S, Picciocchi A, Debeurme F, Vivès C, Hesse AM, Ferro M, Grunwald D, Stieglitz H, Thepchatri P, Smith SME, Fieschi F, Stasia MJ. Down-regulation of NOX2 activity in phagocytes mediated by ATM-kinase dependent phosphorylation. Free Radic Biol Med 2017; 113:1-15. [PMID: 28916473 PMCID: PMC5699957 DOI: 10.1016/j.freeradbiomed.2017.09.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 08/16/2017] [Accepted: 09/09/2017] [Indexed: 11/18/2022]
Abstract
NADPH oxidases (NOX) have many biological roles, but their regulation to control production of potentially toxic ROS molecules remains unclear. A previously identified insertion sequence of 21 residues (called NIS) influences NOX activity, and its predicted flexibility makes it a good candidate for providing a dynamic switch controlling the NOX active site. We constructed NOX2 chimeras in which NIS had been deleted or exchanged with those from other NOXs (NIS1, 3 and 4). All contained functional heme and were expressed normally at the plasma membrane of differentiated PLB-985 cells. However, NOX2-ΔNIS and NOX2-NIS1 had neither NADPH-oxidase nor reductase activity and exhibited abnormal translocation of p47phox and p67phox to the phagosomal membrane. This suggested a functional role of NIS. Interestingly after activation, NOX2-NIS3 cells exhibited superoxide overproduction compared with wild-type cells. Paradoxically, the Vmax of purified unstimulated NOX2-NIS3 was only one-third of that of WT-NOX2. We therefore hypothesized that post-translational events regulate NOX2 activity and differ between NOX2-NIS3 and WT-NOX2. We demonstrated that Ser486, a phosphorylation target of ataxia telangiectasia mutated kinase (ATM kinase) located in the NIS of NOX2 (NOX2-NIS), was phosphorylated in purified cytochrome b558 after stimulation with phorbol 12-myristate-13-acetate (PMA). Moreover, ATM kinase inhibition and a NOX2 Ser486Ala mutation enhanced NOX activity whereas a Ser486Glu mutation inhibited it. Thus, the absence of Ser486 in NIS3 could explain the superoxide overproduction in the NOX2-NIS3 mutant. These results suggest that PMA-stimulated NOX2-NIS phosphorylation by ATM kinase causes a dynamic switch that deactivates NOX2 activity. We hypothesize that this downregulation is defective in NOX2-NIS3 mutant because of the absence of Ser486.
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Affiliation(s)
- Sylvain Beaumel
- Univ. Grenoble Alpes, CNRS, TIMC-IMAG, F-38000 Grenoble, France; CDiReC, Pôle Biologie, CHU de Grenoble, Grenoble F-38043, France
| | - Antoine Picciocchi
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Franck Debeurme
- Univ. Grenoble Alpes, CNRS, TIMC-IMAG, F-38000 Grenoble, France
| | - Corinne Vivès
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Anne-Marie Hesse
- Univ. Grenoble Alpes, INSERM, CEA, Laboratoire de Biologie à Grande Echelle, Grenoble F-38054, France; Univ. Grenoble Alpes, CEA, INSERM, Laboratoire de Biologie du Cancer et de l'infection, Grenoble F-38000, France
| | - Myriam Ferro
- Univ. Grenoble Alpes, INSERM, CEA, Laboratoire de Biologie à Grande Echelle, Grenoble F-38054, France
| | - Didier Grunwald
- Univ. Grenoble Alpes, CEA, INSERM, Laboratoire de Biologie du Cancer et de l'infection, Grenoble F-38000, France
| | - Heather Stieglitz
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Pahk Thepchatri
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Susan M E Smith
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, GA, USA
| | - Franck Fieschi
- Univ. Grenoble Alpes, CNRS, CEA, Institut de Biologie Structurale, F-38044 Grenoble, France
| | - Marie José Stasia
- Univ. Grenoble Alpes, CNRS, TIMC-IMAG, F-38000 Grenoble, France; CDiReC, Pôle Biologie, CHU de Grenoble, Grenoble F-38043, France.
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Jha JC, Banal C, Okabe J, Gray SP, Hettige T, Chow BSM, Thallas-Bonke V, De Vos L, Holterman CE, Coughlan MT, Power DA, Skene A, Ekinci EI, Cooper ME, Touyz RM, Kennedy CR, Jandeleit-Dahm K. NADPH Oxidase Nox5 Accelerates Renal Injury in Diabetic Nephropathy. Diabetes 2017; 66:2691-2703. [PMID: 28747378 DOI: 10.2337/db16-1585] [Citation(s) in RCA: 102] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 07/18/2017] [Indexed: 11/13/2022]
Abstract
NADPH oxidase-derived excessive production of reactive oxygen species (ROS) in the kidney plays a key role in mediating renal injury in diabetes. Pathological changes in diabetes include mesangial expansion and accumulation of extracellular matrix (ECM) leading to glomerulosclerosis. There is a paucity of data about the role of the Nox5 isoform of NADPH oxidase in animal models of diabetic nephropathy since Nox5 is absent in the mouse genome. Thus, we examined the role of Nox5 in human diabetic nephropathy in human mesangial cells and in an inducible human Nox5 transgenic mouse exposed to streptozotocin-induced diabetes. In human kidney biopsies, Nox5 was identified to be expressed in glomeruli, which appeared to be increased in diabetes. Colocalization demonstrated Nox5 expression in mesangial cells. In vitro, silencing of Nox5 in human mesangial cells was associated with attenuation of the hyperglycemia and TGF-β1-induced enhanced ROS production, increased expression of profibrotic and proinflammatory mediators, and increased TRPC6, PKC-α, and PKC-β expression. In vivo, vascular smooth muscle cell/mesangial cell-specific overexpression of Nox5 in a mouse model of diabetic nephropathy showed enhanced glomerular ROS production, accelerated glomerulosclerosis, mesangial expansion, and ECM protein (collagen IV and fibronectin) accumulation as well as increased macrophage infiltration and expression of the proinflammatory chemokine MCP-1. Collectively, this study provides evidence of a role for Nox5 and its derived ROS in promoting progression of diabetic nephropathy.
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Affiliation(s)
- Jay C Jha
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Claudine Banal
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Jun Okabe
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
- Human Epigenetics Laboratory, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Stephen P Gray
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Thushan Hettige
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Bryna S M Chow
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Vicki Thallas-Bonke
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Lisanne De Vos
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
| | - Chet E Holterman
- Kidney Research Centre, Department of Medicine, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Melinda T Coughlan
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - David A Power
- Department of Nephrology and Institute of Breathing and Sleep, Austin Health, Heidelberg, Australia
| | - Alison Skene
- Department of Anatomical Pathology, Austin Health, Heidelberg, Australia
| | - Elif I Ekinci
- Endocrine Centre, Austin Health, Repatriation Campus, Heidelberg, Australia
| | - Mark E Cooper
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
| | - Rhian M Touyz
- Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, U.K
| | - Chris R Kennedy
- Kidney Research Centre, Department of Medicine, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Karin Jandeleit-Dahm
- JDRF Danielle Alberti Memorial Centre for Diabetic Complications, Diabetic Complications Division, Baker IDI Heart and Diabetes Institute, Melbourne, Australia
- Department of Diabetes, Central Clinical School, Monash University, Melbourne, Australia
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The emerging role of NADPH oxidase NOX5 in vascular disease. Clin Sci (Lond) 2017; 131:981-990. [PMID: 28473473 DOI: 10.1042/cs20160846] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 03/14/2017] [Accepted: 03/19/2017] [Indexed: 01/11/2023]
Abstract
Oxidative stress is a consequence of up-regulation of pro-oxidant enzyme-induced reactive oxygen species (ROS) production and concomitant depletion of antioxidants. Elevated levels of ROS act as an intermediate and are the common denominator for various diseases including diabetes-associated macro-/micro-vascular complications and hypertension. A range of enzymes are capable of generating ROS, but the pro-oxidant enzyme family, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases (NOXs), are the only enzymes known to be solely dedicated to ROS generation in the vascular tissues, kidney, aortas and eyes. While there is convincing evidence for a role of NOX1 in vascular and eye disease and for NOX4 in renal injury, the role of NOX5 in disease is less clear. Although NOX5 is highly up-regulated in humans in disease, it is absent in rodents. Thus, so far it has not been possible to study NOX5 in traditional mouse or rat models of disease. In the present review, we summarize and critically analyse the emerging evidence for a pathophysiological role of NOX5 in disease including the expression, regulation and molecular and cellular mechanisms which have been demonstrated to be involved in NOX5 activation.
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Abstract
NADPH oxidases (NOXs) are the only enzymes exclusively dedicated to reactive oxygen species (ROS) generation. Dysregulation of these polytopic membrane proteins impacts the redox signaling cascades that control cell proliferation and death. We describe the atomic crystal structures of the catalytic flavin adenine dinucleotide (FAD)- and heme-binding domains of Cylindrospermum stagnale NOX5. The two domains form the core subunit that is common to all seven members of the NOX family. The domain structures were then docked in silico to provide a generic model for the NOX family. A linear arrangement of cofactors (NADPH, FAD, and two membrane-embedded heme moieties) injects electrons from the intracellular side across the membrane to a specific oxygen-binding cavity on the extracytoplasmic side. The overall spatial organization of critical interactions is revealed between the intracellular loops on the transmembrane domain and the NADPH-oxidizing dehydrogenase domain. In particular, the C terminus functions as a toggle switch, which affects access of the NADPH substrate to the enzyme. The essence of this mechanistic model is that the regulatory cues conformationally gate NADPH-binding, implicitly providing a handle for activating/deactivating the very first step in the redox chain. Such insight provides a framework to the discovery of much needed drugs that selectively target the distinct members of the NOX family and interfere with ROS signaling.
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Cifuentes-Pagano ME, Meijles DN, Pagano PJ. Nox Inhibitors & Therapies: Rational Design of Peptidic and Small Molecule Inhibitors. Curr Pharm Des 2016; 21:6023-35. [PMID: 26510437 DOI: 10.2174/1381612821666151029112013] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 10/27/2015] [Indexed: 12/15/2022]
Abstract
Oxidative stress-related diseases underlie many if not all of the major leading causes of death in United States and the Western World. Thus, enormous interest from both academia and pharmaceutical industry has been placed on the development of agents which attenuate oxidative stress. With that in mind, great efforts have been placed in the development of inhibitors of NADPH oxidase (Nox), the major enzymatic source of reactive oxygen species and oxidative stress in many cells and tissue. The regulation of a catalytically active Nox enzyme involves numerous protein-protein interactions which, in turn, afford numerous targets for inhibition of its activity. In this review, we will provide an updated overview of the available Nox inhibitors, both peptidic and small molecules, and discuss the body of data related to their possible mechanisms of action and specificity towards each of the various isoforms of Nox. Indeed, there have been some very notable successes. However, despite great commitment by many in the field, the need for efficacious and well-characterized, isoform-specific Nox inhibitors, essential for the treatment of major diseases as well as for delineating the contribution of a given Nox in physiological redox signalling, continues to grow.
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Affiliation(s)
| | | | - Patrick J Pagano
- Department of Pharmacology & Chemical Biology, Vascular Medicine Institute, University of Pittsburgh School of Medicine, Biomedical Science Tower, 12th Floor, Room E1247, 200 Lothrop St., Pittsburgh, PA 15261, USA.
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Chen F, Yin C, Dimitropoulou C, Fulton DJR. Cloning, Characteristics, and Functional Analysis of Rabbit NADPH Oxidase 5. Front Physiol 2016; 7:284. [PMID: 27486403 PMCID: PMC4950256 DOI: 10.3389/fphys.2016.00284] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 06/23/2016] [Indexed: 12/31/2022] Open
Abstract
Background: Nox5 was the last member of the Nox enzyme family to be identified. Functionally distinct from the other Nox isoforms, our understanding of its physiological significance has been hampered by the absence of Nox5 in mouse and rat genomes. Nox5 is present in the genomes of other species such as the rabbit that have broad utility as models of cardiovascular disease. However, the mRNA sequence, characteristics, and functional analysis of rabbit Nox5 has not been fully defined and were the goals of the current study. Methods: Rabbit Nox5 was amplified from rabbit tissue, cloned, and sequenced. COS-7 cells were employed for expression and functional analysis via Western blotting and measurements of superoxide. We designed and synthesized miRNAs selectively targeting rabbit Nox5. The nucleotide and amino acid sequences of rabbit Nox5 were aligned with those of putative rabbit isoforms (X1, X2, X3, and X4). A phylogenetic tree was generated based on the mRNA sequence for Nox5 from rabbit and other species. Results: Sequence alignment revealed that the identified rabbit Nox5 was highly conserved with the predicted sequence of rabbit Nox5. Cell based experiments reveal that rabbit Nox5 was robustly expressed and produced superoxide at rest and in a calcium and PMA-dependent manner that was susceptible to superoxide dismutase and the flavoprotein inhibitor, DPI. miRNA-1 was shown to be most effective in down-regulating the expression of rabbit Nox5. Phylogenetic analysis revealed a close relationship between rabbit and armadillo Nox5. Rabbit Nox5 was relatively closely related to human Nox5, but lies in a distinct cluster. Conclusion: Our study establishes the suitability of the rabbit as a model organism to further our understanding of the role of Nox5 in cardiovascular and other diseases and provides new information on the genetic relationship of Nox5 genes in different species.
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Affiliation(s)
- Feng Chen
- Department of Forensic Medicine, Nanjing Medical UniversityNanjing, Jiangsu, China; Vascular Biology Center, Medical College of Georgia at Augusta UniversityAugusta, GA, USA
| | - Caiyong Yin
- Department of Forensic Medicine, Nanjing Medical University Nanjing, Jiangsu, China
| | | | - David J R Fulton
- Vascular Biology Center, Medical College of Georgia at Augusta University Augusta, GA, USA
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Petrushanko IY, Lobachev VM, Kononikhin AS, Makarov AA, Devred F, Kovacic H, Kubatiev AA, Tsvetkov PO. Oxidation of Са2+-Binding Domain of NADPH Oxidase 5 (NOX5): Toward Understanding the Mechanism of Inactivation of NOX5 by ROS. PLoS One 2016; 11:e0158726. [PMID: 27391469 PMCID: PMC4938588 DOI: 10.1371/journal.pone.0158726] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 06/21/2016] [Indexed: 11/18/2022] Open
Abstract
NOX5 protein, one of the most active generators of reactive oxygen species (ROS), plays an important role in many processes, including regulation of cell growth, death and differentiation. Because of its central role in ROS generation, it needs to be tightly regulated to guarantee cellular homeostasis. Contrary to other members of NADPH-oxidases family, NOX5 has its own regulatory calcium-binding domain and thus could be activated directly by calcium ions. While several mechanisms of activation have been described, very little is known about the mechanisms that could prevent the overproduction of ROS by NOX5. In the present study using calorimetric methods and circular dichroism we found that oxidation of cysteine and methionine residues of NOX5 decreases binding of Ca2+ ions and perturbs both secondary and tertiary structure of protein. Our data strongly suggest that oxidation of calcium-binding domain of NOX5 could be implicated in its inactivation, serving as a possible defense mechanism against oxidative stress.
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Affiliation(s)
- Irina Yu Petrushanko
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov Street 32, 119991 Moscow, Russia
| | - Vladimir M. Lobachev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov Street 32, 119991 Moscow, Russia
| | - Alexey S. Kononikhin
- Moscow Institute of Physics and Technology, 141700 Dolgoprudnyi, Moscow Region, Russia
| | - Alexander A. Makarov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Vavilov Street 32, 119991 Moscow, Russia
| | - Francois Devred
- Aix-Marseille University, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 13385 Marseille, France
| | - Hervé Kovacic
- Aix-Marseille University, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 13385 Marseille, France
| | - Aslan A. Kubatiev
- Institute of General Pathology and Pathophysiology, RAMS, 125315, Moscow, Russian Federation
| | - Philipp O. Tsvetkov
- Aix-Marseille University, Inserm, CRO2 UMR_S 911, Faculté de Pharmacie, 13385 Marseille, France
- Institute of General Pathology and Pathophysiology, RAMS, 125315, Moscow, Russian Federation
- * E-mail:
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Chen F, Haigh S, Yu Y, Benson T, Wang Y, Li X, Dou H, Bagi Z, Verin AD, Stepp DW, Csanyi G, Chadli A, Weintraub NL, Smith SME, Fulton DJR. Nox5 stability and superoxide production is regulated by C-terminal binding of Hsp90 and CO-chaperones. Free Radic Biol Med 2015; 89:793-805. [PMID: 26456056 PMCID: PMC4751585 DOI: 10.1016/j.freeradbiomed.2015.09.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 08/15/2015] [Accepted: 09/03/2015] [Indexed: 10/22/2022]
Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone that orchestrates the folding and stability of proteins that regulate cellular signaling, proliferation and inflammation. We have previously shown that Hsp90 controls the production of reactive oxygen species by modulating the activity of Noxes1-3 and 5, but not Nox4. The goal of the current study was to define the regions on Nox5 that bind Hsp90 and determine how Hsp90 regulates enzyme activity. In isolated enzyme activity assays, we found that Hsp90 inhibitors selectively decrease superoxide, but not hydrogen peroxide, production. The addition of Hsp90 alone only modestly increases Nox5 enzyme activity but in combination with the co-chaperones, Hsp70, HOP, Hsp40, and p23 it robustly stimulated superoxide, but not hydrogen peroxide, production. Proximity ligation assays reveal that Nox5 and Hsp90 interact in intact cells. In cell lysates using a co-IP approach, Hsp90 binds to Nox5 but not Nox4, and the degree of binding can be influenced by calcium-dependent stimuli. Inhibition of Hsp90 induced the degradation of full length, catalytically inactive and a C-terminal fragment (aa398-719) of Nox5. In contrast, inhibition of Hsp90 did not affect the expression levels of N-terminal fragments (aa1-550) suggesting that Hsp90 binding maintains the stability of C-terminal regions. In Co-IP assays, Hsp90 was bound only to the C-terminal region of Nox5. Further refinement using deletion analysis revealed that the region between aa490-550 mediates Hsp90 binding. Converse mapping experiments show that the C-terminal region of Nox5 bound to the M domain of Hsp90 (aa310-529). In addition to Hsp90, Nox5 bound other components of the foldosome including co-chaperones Hsp70, HOP, p23 and Hsp40. Silencing of HOP, Hsp40 and p23 reduced Nox5-dependent superoxide. In contrast, increased expression of Hsp70 decreased Nox5 activity whereas a mutant of Hsp70 failed to do so. Inhibition of Hsp90 results in the loss of higher molecular weight complexes of Nox5 and decreased interaction between monomers. Collectively these results show that the C-terminal region of Nox5 binds to the M domain of Hsp90 and that the binding of Hsp90 and select co-chaperones facilitate oligomerization and the efficient production of superoxide.
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Affiliation(s)
- Feng Chen
- Department of Forensic Medicine, Nanjing Medical University, Nanjing, Jiangsu, 210029 China; Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA.
| | - Steven Haigh
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Yanfang Yu
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Tyler Benson
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Yusi Wang
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Xueyi Li
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Huijuan Dou
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Zsolt Bagi
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Alexander D Verin
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - David W Stepp
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Gabor Csanyi
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Ahmed Chadli
- Cancer Research Center, Molecular Chaperones Program, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Neal L Weintraub
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA
| | - Susan M E Smith
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw GA 30152, USA
| | - David J R Fulton
- Vascular Biology Center, Georgia Regents University, Augusta, Georgia 30912, USA.
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Manea A, Manea SA, Gan AM, Constantin A, Fenyo IM, Raicu M, Muresian H, Simionescu M. Human monocytes and macrophages express NADPH oxidase 5; a potential source of reactive oxygen species in atherosclerosis. Biochem Biophys Res Commun 2015; 461:172-9. [DOI: 10.1016/j.bbrc.2015.04.021] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2015] [Accepted: 04/03/2015] [Indexed: 12/31/2022]
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Abstract
Since the first demonstration of Nox enzyme expression in the kidney in the early 1990s and the subsequent identification of Nox4, or RENOX, a decade later, it has become apparent that the Nox family of reactive oxygen species (ROS) generating enzymes plays an integral role in the normal physiological function of the kidney. As our knowledge of Nox expression patterns and functions in various structures and specialized cell types within the kidney grows, so does the realization that Nox-derived oxidative stress contributes significantly to a wide variety of renal pathologies through their ability to modify lipids and proteins, damage DNA and activate transcriptional programmes. Diverse studies demonstrate key roles for Nox-derived ROS in kidney fibrosis, particularly in settings of chronic renal disease such as diabetic nephropathy. As the most abundant Nox family member in the kidney, much emphasis has been placed on the role of Nox4 in this setting. However, an ever growing body of work continues to uncover key roles for other Nox family members, not only in diabetic kidney disease, but in a diverse array of renal pathological conditions. The objective of the present review is to highlight the latest novel developments in renal Nox biology with an emphasis not only on diabetic nephropathy but many of the other renal disease contexts where oxidative stress is implicated.
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Chuong Nguyen MV, Lardy B, Paclet MH, Rousset F, Berthier S, Baillet A, Grange L, Gaudin P, Morel F. [NADPH oxidases, Nox: new isoenzymes family]. Med Sci (Paris) 2015; 31:43-52. [PMID: 25658730 DOI: 10.1051/medsci/20153101012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
NADPH oxidases, Nox, are a family of isoenzymes, composed of seven members, whose sole function is to produce reactive oxygen species (ROS). Although Nox catalyze the same enzymatic reaction, they acquired from a common ancestor during evolution, specificities related to their tissue expression, subcellular localization, activation mechanisms and regulation. Their functions could vary depending on the pathophysiological state of the tissues. Indeed, ROS are not only bactericidal weapons in phagocytes but also essential cellular signaling molecules and their overproduction is involved in chronic diseases and diseases of aging. The understanding of the mechanisms involved in the function of Nox and the emergence of Nox inhibitors, require a thorough knowledge of their nature and structure. The objectives of this review are to highlight, in a structure/function approach, the main similar and differentiated properties shared by the human Nox isoenzymes.
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Affiliation(s)
- Minh Vu Chuong Nguyen
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France
| | - Bernard Lardy
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France - DBTP (département de biochimie, toxicologie et pharmacologie), institut de biologie et pathologie, CHU de Grenoble, France
| | - Marie-Hélène Paclet
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France - DBTP (département de biochimie, toxicologie et pharmacologie), institut de biologie et pathologie, CHU de Grenoble, France
| | - Francis Rousset
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France
| | - Sylvie Berthier
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France
| | - Athan Baillet
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France - Clinique universitaire de rhumatologie, Hôpital Sud, CHU de Grenoble, France
| | - Laurent Grange
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France - Clinique universitaire de rhumatologie, Hôpital Sud, CHU de Grenoble, France
| | - Philippe Gaudin
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France - Clinique universitaire de rhumatologie, Hôpital Sud, CHU de Grenoble, France
| | - Françoise Morel
- GREPI (groupe de recherche et d'étude du processus inflammatoire), université Joseph Fourier, Grenoble, France EFS Rhône-Alpes, 29, avenue des Maquis du Grésivaudan, 38700 La Tronche, France
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Smith SME, Min J, Ganesh T, Diebold B, Kawahara T, Zhu Y, McCoy J, Sun A, Snyder JP, Fu H, Du Y, Lewis I, Lambeth JD. Ebselen and congeners inhibit NADPH oxidase 2-dependent superoxide generation by interrupting the binding of regulatory subunits. ACTA ACUST UNITED AC 2014; 19:752-63. [PMID: 22726689 DOI: 10.1016/j.chembiol.2012.04.015] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Revised: 04/18/2012] [Accepted: 04/27/2012] [Indexed: 02/07/2023]
Abstract
NADPH oxidases (Nox) are a primary source of reactive oxygen species (ROS), which function in normal physiology and, when overproduced, in pathophysiology. Recent studies using mice deficient in Nox2 identify this isoform as a novel target against Nox2-implicated inflammatory diseases. Nox2 activation depends on the binding of the proline-rich domain of its heterodimeric partner p22phox to p47phox. A high-throughput screen that monitored this interaction via fluorescence polarization identified ebselen and several of its analogs as inhibitors. Medicinal chemistry was performed to explore structure-activity relationships and to optimize potency. Ebselen and analogs potently inhibited Nox1 and Nox2 activity but were less effective against other isoforms. Ebselen also blocked translocation of p47phox to neutrophil membranes. Thus, ebselen and its analogs represent a class of compounds that inhibit ROS generation by interrupting the assembly of Nox2-activating regulatory subunits.
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Affiliation(s)
- Susan M E Smith
- Department of Pathology, Emory School of Medicine, 615 Michael Street, Atlanta, GA 30322, USA
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Yu P, Han W, Villar VAM, Yang Y, Lu Q, Lee H, Li F, Quinn MT, Gildea JJ, Felder RA, Jose PA. Unique role of NADPH oxidase 5 in oxidative stress in human renal proximal tubule cells. Redox Biol 2014; 2:570-9. [PMID: 24688893 PMCID: PMC3969603 DOI: 10.1016/j.redox.2014.01.020] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Revised: 01/28/2014] [Accepted: 01/30/2014] [Indexed: 12/22/2022] Open
Abstract
NADPH oxidases are the major sources of reactive oxygen species in cardiovascular, neural, and kidney cells. The NADPH oxidase 5 (NOX5) gene is present in humans but not rodents. Because Nox isoforms in renal proximal tubules (RPTs) are involved in the pathogenesis of hypertension, we tested the hypothesis that NOX5 is differentially expressed in RPT cells from normotensive (NT) and hypertensive subjects (HT). We found that NOX5 mRNA, total NOX5 protein, and apical membrane NOX5 protein were 4.2±0.7-fold, 5.2±0.7-fold, and 2.8±0.5-fold greater in HT than NT. Basal total NADPH oxidase activity was 4.5±0.2-fold and basal NOX5 activity in NOX5 immunoprecipitates was 6.2±0.2-fold greater in HT than NT (P=<0.001, n=6-14/group). Ionomycin increased total NOX and NOX5 activities in RPT cells from HT (P<0.01, n=4, ANOVA), effects that were abrogated by pre-treatment of the RPT cells with diphenylene-iodonium or superoxide dismutase. Silencing NOX5 using NOX5-siRNA decreased NADPH oxidase activity (-45.1±3.2% vs. mock-siRNA, n=6-8) in HT. D1-like receptor stimulation decreased NADPH oxidase activity to a greater extent in NT (-32.5±1.8%) than HT (-14.8±1.8). In contrast to the marked increase in expression and activity of NOX5 in HT, NOX1 mRNA and protein were minimally increased in HT, relative to NT; total NOX2 and NOX4 proteins were not different between HT and NT, while the increase in apical RPT cell membrane NOX1, NOX2, and NOX4 proteins in HT, relative to NT, was much less than those observed with NOX5. Thus, we demonstrate, for the first time, that NOX5 is expressed in human RPT cells and to greater extent than the other Nox isoforms in HT than NT. We suggest that the increased expression of NOX5, which may be responsible for the increased oxidative stress in RPT cells in human essential hypertension, is caused, in part, by a defective renal dopaminergic system.
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Affiliation(s)
- Peiying Yu
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Weixing Han
- Department of Cardiovascular Medicine, The First Hospital Affiliated to Anhui Medical University, Hefei, Anhui, PR China
| | - Van Anthony M Villar
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Yu Yang
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Quansheng Lu
- Department of Pediatrics, Georgetown University Medical Center, Washington, DC, USA
| | - Hewang Lee
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Fengmin Li
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Mark T Quinn
- Department of Immunology and Infectious Diseases, Montana State University, Bozeman, MT, USA
| | - John J Gildea
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA, USA
| | - Robin A Felder
- Department of Pathology, University of Virginia Health Sciences Center, Charlottesville, VA, USA
| | - Pedro A Jose
- Division of Nephrology, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD, USA ; Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
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Holterman CE, Thibodeau JF, Towaij C, Gutsol A, Montezano AC, Parks RJ, Cooper ME, Touyz RM, Kennedy CRJ. Nephropathy and elevated BP in mice with podocyte-specific NADPH oxidase 5 expression. J Am Soc Nephrol 2013; 25:784-97. [PMID: 24262797 DOI: 10.1681/asn.2013040371] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
NADPH oxidase (Nox) enzymes are a significant source of reactive oxygen species, which contribute to glomerular podocyte dysfunction. Although studies have implicated Nox1, -2, and -4 in several glomerulopathies, including diabetic nephropathy, little is known regarding the role of Nox5 in this context. We examined Nox5 expression and regulation in kidney biopsies from diabetic patients, cultured human podocytes, and a novel mouse model. Nox5 expression increased in human diabetic glomeruli compared with nondiabetic glomeruli. Stimulation with angiotensin II upregulated Nox5 expression in human podocyte cultures and increased reactive oxygen species generation. siRNA-mediated Nox5 knockdown inhibited angiotensin II-stimulated production of reactive oxygen species and altered podocyte cytoskeletal dynamics, resulting in an Rac-mediated motile phenotype. Because the Nox5 gene is absent in rodents, we generated transgenic mice expressing human Nox5 in a podocyte-specific manner (Nox5(pod+)). Nox5(pod+) mice exhibited early onset albuminuria, podocyte foot process effacement, and elevated systolic BP. Subjecting Nox5(pod+) mice to streptozotocin-induced diabetes further exacerbated these changes. Our data show that renal Nox5 is upregulated in human diabetic nephropathy and may alter filtration barrier function and systolic BP through the production of reactive oxygen species. These findings provide the first evidence that podocyte Nox5 has an important role in impaired renal function and hypertension.
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Affiliation(s)
- Chet E Holterman
- Kidney Research Centre, Division of Nephrology, Department of Medicine, and
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Cadmium and cellular signaling cascades: interactions between cell death and survival pathways. Arch Toxicol 2013; 87:1743-86. [PMID: 23982889 DOI: 10.1007/s00204-013-1110-9] [Citation(s) in RCA: 156] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 07/29/2013] [Indexed: 12/20/2022]
Abstract
Cellular stress elicited by the toxic metal Cd(2+) does not coerce the cell into committing to die from the onset. Rather, detoxification and adaptive processes are triggered concurrently, allowing survival until normal function is restored. With high Cd(2+), death pathways predominate. However, if sublethal stress levels affect cells for prolonged periods, as in chronic low Cd(2+) exposure, adaptive and survival mechanisms may deregulate, such that tumorigenesis ensues. Hence, death and malignancy are the two ends of a continuum of cellular responses to Cd(2+), determined by magnitude and duration of Cd(2+) stress. Signaling cascades are the key factors affecting cellular reactions to Cd(2+). This review critically surveys recent literature to outline major features of death and survival signaling pathways as well as their activation, interactions and cross talk in cells exposed to Cd(2+). Under physiological conditions, receptor activation generates 2nd messengers, which are short-lived and act specifically on effectors through their spatial and temporal dynamics to transiently alter effector activity. Cd(2+) recruits physiological 2nd messenger systems, in particular Ca(2+) and reactive oxygen species (ROS), which control key Ca(2+)- and redox-sensitive molecular switches dictating cell function and fate. Severe ROS/Ca(2+) signals activate cell death effectors (ceramides, ASK1-JNK/p38, calpains, caspases) and/or cause irreversible damage to vital organelles, such as mitochondria and endoplasmic reticulum (ER), whereas low localized ROS/Ca(2+) levels act as 2nd messengers promoting cellular adaptation and survival through signal transduction (ERK1/2, PI3K/Akt-PKB) and transcriptional regulators (Ref1-Nrf2, NF-κB, Wnt, AP-1, bestrophin-3). Other cellular proteins and processes targeted by ROS/Ca(2+) (metallothioneins, Bcl-2 proteins, ubiquitin-proteasome system, ER stress-associated unfolded protein response, autophagy, cell cycle) can evoke death or survival. Hence, temporary or permanent disruptions of ROS/Ca(2+) induced by Cd(2+) play a crucial role in eliciting, modulating and linking downstream cell death and adaptive and survival signaling cascades.
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Cox JA. Divers models of divalent cation interaction to calcium-binding proteins: techniques and anthology. Methods Mol Biol 2013; 963:15-35. [PMID: 23296602 DOI: 10.1007/978-1-62703-230-8_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Intracellular Ca(2+)-binding proteins (CaBPs) are sensors of the calcium signal and several of them even shape the signal. Most of them are equipped with at least two EF-hand motifs designed to bind Ca(2+). Their affinities are very variable, can display cooperative effects, and can be modulated by physiological Mg(2+) concentrations. These binding phenomena are monitored by four major techniques: equilibrium dialysis, fluorimetry with fluorescent Ca(2+) indicators, flow dialysis, and isothermal titration calorimetry. In the last quarter of the twentieth century reports on the ion-binding characteristics of several abundant wild-type CaBPs were published. With the advent of recombinant CaBPs it became possible to determine these properties on previously inaccessible proteins. Here I report on studies by our group carried out in the last decade on eight families of recombinant CaBPs, their mutants, or truncated domains. Moreover this chapter deals with the currently used methods for quantifying the binding of Ca(2+) and Mg(2+) to CaBPs.
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Affiliation(s)
- Jos A Cox
- Department of Biochemistry, University of Geneva, Geneva, Switzerland.
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Berthier S, Nguyen MVC, Baillet A, Hograindleur MA, Paclet MH, Polack B, Morel F. Molecular interface of S100A8 with cytochrome b558 and NADPH oxidase activation. PLoS One 2012; 7:e40277. [PMID: 22808130 PMCID: PMC3393751 DOI: 10.1371/journal.pone.0040277] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 06/04/2012] [Indexed: 12/18/2022] Open
Abstract
S100A8 and S100A9 are two calcium binding Myeloid Related Proteins, and important mediators of inflammatory diseases. They were recently introduced as partners for phagocyte NADPH oxidase regulation. However, the precise mechanism of their interaction remains elusive. We had for aim (i) to evaluate the impact of S100 proteins on NADPH oxidase activity; (ii) to characterize molecular interaction of either S100A8, S100A9, or S100A8/S100A9 heterocomplex with cytochrome b558; and (iii) to determine the S100A8 consensus site involved in cytochrome b558/S100 interface. Recombinant full length or S100A9-A8 truncated chimera proteins and ExoS-S100 fusion proteins were expressed in E. coli and in P. aeruginosa respectively. Our results showed that S100A8 is the functional partner for NADPH oxidase activation contrary to S100A9, however, the loading with calcium and a combination with phosphorylated S100A9 are essential in vivo. Endogenous S100A9 and S100A8 colocalize in differentiated and PMA stimulated PLB985 cells, with Nox2/gp91phox and p22phox. Recombinant S100A8, loaded with calcium and fused with the first 129 or 54 N-terminal amino acid residues of the P. aeruginosa ExoS toxin, induced a similar oxidase activation in vitro, to the one observed with S100A8 in the presence of S100A9 in vivo. This suggests that S100A8 is the essential component of the S100A9/S100A8 heterocomplex for oxidase activation. In this context, recombinant full-length rS100A9-A8 and rS100A9-A8 truncated 90 chimera proteins as opposed to rS100A9-A8 truncated 86 and rS100A9-A8 truncated 57 chimeras, activate the NADPH oxidase function of purified cytochrome b558 suggesting that the C-terminal region of S100A8 is directly involved in the molecular interface with the hemoprotein. The data point to four strategic 87HEES90 amino acid residues of the S100A8 C-terminal sequence that are involved directly in the molecular interaction with cytochrome b558 and then in the phagocyte NADPH oxidase activation.
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Affiliation(s)
- Sylvie Berthier
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
| | - Minh Vu Chuong Nguyen
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
- * E-mail:
| | - Athan Baillet
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
- Clinic of Rheumatology, Centre Hospitalier Universitaire (CHU), Grenoble, France
| | - Marc-André Hograindleur
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
| | - Marie-Hélène Paclet
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
- « Laboratoire des Enzymes et des Protéines », Centre Hospitalier Universitaire (CHU), Grenoble, France
- « Institut de Biologie et Pathologie », Centre Hospitalier Universitaire (CHU), Grenoble, France
| | - Benoît Polack
- « Institut de Biologie et Pathologie », Centre Hospitalier Universitaire (CHU), Grenoble, France
- Techniques de l’Ingénierie Médicale et de la Complexité–Informatique, Mathématiques et Applications de Grenoble (TIMC-IMAG) Unité Mixte de Recherche (UMR) 5525 Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier UJF, Grenoble, France
| | - Françoise Morel
- Groupe de Recherche et d’Etude du Processus Inflammatoire (GREPI), Laboratoire “Aging Imaging Modeling” (AGIM), Formation de Recherche en évolution (FRE) Centre National de la Recherche Scientifique CNRS 3405, Université Joseph Fourier UJF, Grenoble, France
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Lassègue B, San Martín A, Griendling KK. Biochemistry, physiology, and pathophysiology of NADPH oxidases in the cardiovascular system. Circ Res 2012; 110:1364-90. [PMID: 22581922 PMCID: PMC3365576 DOI: 10.1161/circresaha.111.243972] [Citation(s) in RCA: 587] [Impact Index Per Article: 48.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The NADPH oxidase (Nox) enzymes are critical mediators of cardiovascular physiology and pathophysiology. These proteins are expressed in virtually all cardiovascular cells, and regulate such diverse functions as differentiation, proliferation, apoptosis, senescence, inflammatory responses and oxygen sensing. They target a number of important signaling molecules, including kinases, phosphatases, transcription factors, ion channels, and proteins that regulate the cytoskeleton. Nox enzymes have been implicated in many different cardiovascular pathologies: atherosclerosis, hypertension, cardiac hypertrophy and remodeling, angiogenesis and collateral formation, stroke, and heart failure. In this review, we discuss in detail the biochemistry of Nox enzymes expressed in the cardiovascular system (Nox1, 2, 4, and 5), their roles in cardiovascular cell biology, and their contributions to disease development.
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Affiliation(s)
- Bernard Lassègue
- Division of Cardiology, Department of Medicine, Emory University, Atlanta, GA 30322, USA
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Ghai R, Falconer RJ, Collins BM. Applications of isothermal titration calorimetry in pure and applied research--survey of the literature from 2010. J Mol Recognit 2012; 25:32-52. [PMID: 22213449 DOI: 10.1002/jmr.1167] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Isothermal titration calorimetry (ITC) is a biophysical technique for measuring the formation and dissociation of molecular complexes and has become an invaluable tool in many branches of science from cell biology to food chemistry. By measuring the heat absorbed or released during bond formation, ITC provides accurate, rapid, and label-free measurement of the thermodynamics of molecular interactions. In this review, we survey the recent literature reporting the use of ITC and have highlighted a number of interesting studies that provide a flavour of the diverse systems to which ITC can be applied. These include measurements of protein-protein and protein-membrane interactions required for macromolecular assembly, analysis of enzyme kinetics, experimental validation of molecular dynamics simulations, and even in manufacturing applications such as food science. Some highlights include studies of the biological complex formed by Staphylococcus aureus enterotoxin C3 and the murine T-cell receptor, the mechanism of membrane association of the Parkinson's disease-associated protein α-synuclein, and the role of non-specific tannin-protein interactions in the quality of different beverages. Recent developments in automation are overcoming limitations on throughput imposed by previous manual procedures and promise to greatly extend usefulness of ITC in the future. We also attempt to impart some practical advice for getting the most out of ITC data for those researchers less familiar with the method.
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Affiliation(s)
- Rajesh Ghai
- Institute for Molecular Bioscience (IMB), University of Queensland, St. Lucia, Queensland, 4072, Australia
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Expression of NADPH oxidase (NOX) 5 in rabbit corneal stromal cells. PLoS One 2012; 7:e34440. [PMID: 22511941 PMCID: PMC3325249 DOI: 10.1371/journal.pone.0034440] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Accepted: 03/02/2012] [Indexed: 01/10/2023] Open
Abstract
Purpose To determine whether NOX 5 is expressed in rabbit corneal stromal cells (RCSC). NADPH oxidases (NOXes) are enzymes that preferentially use NADPH as a substrate and generate superoxide. Several isoforms of NOXes function as multi-protein complexes while NOX5 and DUOXs do not require the accessory proteins for their activity and possess calcium binding EF hands. Methods Human NOX5 primers were used to amplify the rabbit NOX5 by RT-PCR. Amplified product was sequenced to confirm its identity. The protein encoded by the NOX5 was identified by western blot analysis. NOX5 siRNA was used to reduce transcript, protein, and calcium stimulated activity. In silico analyses were performed to establish the putative structure, functions, and evolution of rabbit NOX5. Results NOX activity was measured in RCSC with NADPH rather than NADH as a substrate. RT-PCR with NOX5 primers amplified 288 bp product using RCSC cDNA, which, when sequenced, confirmed its identity to human NOX5 mRNA. This sequence was used to predict the rabbit (Oryctolagus cuniculus) NOX5 gene. NOX5 siRNA reduced amounts of NOX5 mRNA in RCSC and reduced ionomycin stimulated superoxide production. A protein of about 65 to 70 kDa encoded by the NOX5 was detected by western blot analysis. In silico analysis predicted a putative rabbit NOX5 protein containing 801 amino acids. Motif searches predicted the presence of at least 3 putative EF-hands in N-terminus and a NOX domain in C terminal region. Conclusions The data document that the NOX5 gene was expressed in cells of lagomorphs unlike rodents, making the rabbit an interesting model to study NOX5 functions. The activity of the rabbit NOX5 was calcium stimulated, a trait of NOX5 in general. NOX5 may also prove to be a useful genetic marker for studying the taxonomic position of lagomorphs and the Glires classification.
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Characterization of the 1st and 2nd EF-hands of NADPH oxidase 5 by fluorescence, isothermal titration calorimetry, and circular dichroism. Chem Cent J 2012; 6:29. [PMID: 22490336 PMCID: PMC3386892 DOI: 10.1186/1752-153x-6-29] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 04/10/2012] [Indexed: 11/16/2022] Open
Abstract
Background Superoxide generated by non-phagocytic NADPH oxidases (NOXs) is of growing importance for physiology and pathobiology. The calcium binding domain (CaBD) of NOX5 contains four EF-hands, each binding one calcium ion. To better understand the metal binding properties of the 1st and 2nd EF-hands, we characterized the N-terminal half of CaBD (NCaBD) and its calcium-binding knockout mutants. Results The isothermal titration calorimetry measurement for NCaBD reveals that the calcium binding of two EF-hands are loosely associated with each other and can be treated as independent binding events. However, the Ca2+ binding studies on NCaBD(E31Q) and NCaBD(E63Q) showed their binding constants to be 6.5 × 105 and 5.0 × 102 M-1 with ΔHs of -14 and -4 kJ/mol, respectively, suggesting that intrinsic calcium binding for the 1st non-canonical EF-hand is largely enhanced by the binding of Ca2+ to the 2nd canonical EF-hand. The fluorescence quenching and CD spectra support a conformational change upon Ca2+ binding, which changes Trp residues toward a more non-polar and exposed environment and also increases its α-helix secondary structure content. All measurements exclude Mg2+-binding in NCaBD. Conclusions We demonstrated that the 1st non-canonical EF-hand of NOX5 has very weak Ca2+ binding affinity compared with the 2nd canonical EF-hand. Both EF-hands interact with each other in a cooperative manner to enhance their Ca2+ binding affinity. Our characterization reveals that the two EF-hands in the N-terminal NOX5 are Ca2+ specific. Graphical abstract
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Bedard K, Jaquet V, Krause KH. NOX5: from basic biology to signaling and disease. Free Radic Biol Med 2012; 52:725-34. [PMID: 22182486 DOI: 10.1016/j.freeradbiomed.2011.11.023] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 11/10/2011] [Accepted: 11/12/2011] [Indexed: 02/07/2023]
Abstract
In mammals, the NADPH oxidase family of enzymes comprises seven members: NOXs 1-5, DUOX1, and DUOX2. All of these enzymes function to move an electron across cellular membranes, transferring it to oxygen to generate the superoxide anion. This generation of reactive oxygen species has important physiological and pathophysiological roles. NOX5 is perhaps the least well understood of these NOX isoforms, in part because the gene is not present in mice or rats. In recent years, however, there has been a rapid increase in our understanding of the NOX5 gene, the structural and biochemical aspects of the NOX5 enzyme, the role NOX5 plays in health and disease, and the development of novel NOX inhibitors. This review takes a look back at some historical aspects of the discovery of NOX5 and summarizes our current understanding of the enzyme.
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Affiliation(s)
- Karen Bedard
- Department of Pathology, Dalhousie University, Halifax, Canada
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Ghouleh IA, Khoo NK, Knaus UG, Griendling KK, Touyz RM, Thannickal VJ, Barchowsky A, Nauseef WM, Kelley EE, Bauer PM, Darley-Usmar V, Shiva S, Cifuentes-Pagano E, Freeman BA, Gladwin MT, Pagano PJ. Oxidases and peroxidases in cardiovascular and lung disease: new concepts in reactive oxygen species signaling. Free Radic Biol Med 2011; 51:1271-88. [PMID: 21722728 PMCID: PMC3205968 DOI: 10.1016/j.freeradbiomed.2011.06.011] [Citation(s) in RCA: 187] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 06/06/2011] [Accepted: 06/07/2011] [Indexed: 12/17/2022]
Abstract
Reactive oxygen species (ROS) are involved in numerous physiological and pathophysiological responses. Increasing evidence implicates ROS as signaling molecules involved in the propagation of cellular pathways. The NADPH oxidase (Nox) family of enzymes is a major source of ROS in the cell and has been related to the progression of many diseases and even environmental toxicity. The complexity of this family's effects on cellular processes stems from the fact that there are seven members, each with unique tissue distribution, cellular localization, and expression. Nox proteins also differ in activation mechanisms and the major ROS detected as their product. To add to this complexity, mounting evidence suggests that other cellular oxidases or their products may be involved in Nox regulation. The overall redox and metabolic status of the cell, specifically the mitochondria, also has implications on ROS signaling. Signaling of such molecules as electrophilic fatty acids has an impact on many redox-sensitive pathologies and thus, as anti-inflammatory molecules, contributes to the complexity of ROS regulation. This review is based on the proceedings of a recent international Oxidase Signaling Symposium at the University of Pittsburgh's Vascular Medicine Institute and Department of Pharmacology and Chemical Biology and encompasses further interaction and discussion among the presenters.
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Affiliation(s)
- Imad Al Ghouleh
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
| | - Nicholas K.H. Khoo
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
| | - Ulla G. Knaus
- Conway Institute, University College Dublin, Dublin, Ireland
| | - Kathy K. Griendling
- Department of Medicine, Division of Cardiology, Emory University, Atlanta, GA
| | - Rhian M. Touyz
- Ottawa Hospital Research Institute, Univ of Ottawa, Ottawa, Ontario, Canada
| | - Victor J. Thannickal
- Pulmonary, Allergy & Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL
| | - Aaron Barchowsky
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA
| | - William M. Nauseef
- Inflammation Program, Department of Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
- Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa
- Veterans Administration Medical Center, Iowa City, IA
| | - Eric E. Kelley
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
- Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA
| | - Phillip M. Bauer
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Victor Darley-Usmar
- Center for Free Radical Biology, University of Alabama at Birmingham, Birmingham, AL
| | - Sruti Shiva
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
| | - Eugenia Cifuentes-Pagano
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
| | - Bruce A. Freeman
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
| | - Mark T. Gladwin
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
- Department of Pulmonary, Allergy & Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Patrick J. Pagano
- Department of Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA
- Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA
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Abstract
The Noxes (NADPH oxidases) are a family of ROS (reactive oxygen species)-generating enzymes. Of the seven family members, four have been identified as important sources of ROS in the vasculature: Nox1, Nox2, Nox4 and Nox5. Although Nox isoforms can be influenced by the same stimulus and co-localize in cellular compartments, their tissue distribution, subcellular regulation, requirement for cofactors and NADPH oxidase subunits and ability to generate specific ROS differ, which may help to understand the multiplicity of biological functions of these oxidases. Nox4 and Nox5 are the newest isoforms identified in the vasculature. Nox4 is the major isoform expressed in renal cells and appear to produce primarily H2O2. The Nox5 isoform produces ROS in response to increased levels of intracellular Ca2+ and does not require the other NADPH oxidase subunits for its activation. The present review focuses on these unique Noxes, Nox4 and Nox5, and provides novel concepts related to the regulation and interaction in the vasculature, and discusses new potential roles for these isoforms in vascular biology.
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