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Nazari B, Jaquet V, Krause KH. NOX family NADPH oxidases in mammals: Evolutionary conservation and isoform-defining sequences. Redox Biol 2023; 66:102851. [PMID: 37595375 PMCID: PMC10458973 DOI: 10.1016/j.redox.2023.102851] [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: 06/28/2023] [Revised: 07/31/2023] [Accepted: 08/11/2023] [Indexed: 08/20/2023] Open
Abstract
NADPH oxidases are superoxide-producing enzymes that play a role in host defense, biosynthetic pathways, as well as cellular signaling. Humans have 7 NOX isoforms (NOX1-5, DUOX1,2), while mice and rats lack NOX5 and therefore have only 6 NOX isoforms. Whether all human NOX isoforms or their subunits (CYBA, NCF1, 2, 4, NOXO1, NOXA1, DUOXA1, 2) are present and conserved in other mammalian species is unknown. In this study, we have analyzed the conservation of the NOX family during mammalian evolution using an in-silico approach. Complete genomic sequences of 164 mammalian species were available. The possible absence of genes coding for NOX isoforms was investigated using the NCBI orthologs database followed by manual curation. Conservation of a given NOX isoform during mammalian evolution was evaluated by multiple alignment and identification of highly conserved sequences. There was no convincing evidence for the absence of NOX2, 3, 4, and DUOX1, 2 in all the available mammalian genome. However, NOX5 was absent in 27 of 31 rodent, in 2 of 3 lagomorph and in 2 out of 18 bat species. NOX1 was absent in all sequenced Afrotheria and Monotremata species, as well as in 3 of 18 bat species. NOXA1 was absent in all Afrotheria and in 3 out of 4 Eulipotyphla species. We also investigated amino acid sequence conservation among given NOX isoforms. Highly conserved sequences were observed for most isoforms except for NOX5. Interestingly, the highly conserved region of NOX2 sequence was relatively small (11 amino acids), as compared to NOX1, 3, 4. The highly conserved domains are different from one NOX isoform to the other, raising the possibility of distinct evolutionary conserved functional domains. Our results shed a new light on the essentiality of different NOX isoforms. We also identified isoform-defining sequences, i.e., hitherto undescribed conserved domains within specific NOX isoforms.
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Affiliation(s)
- Bahareh Nazari
- Department of Pathology & Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Vincent Jaquet
- Department of Pathology & Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland; READS Unit, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Karl-Heinz Krause
- Department of Pathology & Immunology, Faculty of Medicine, University of Geneva, Geneva, Switzerland.
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Miles JA, Egan JL, Fowler JA, Machattou P, Millard AD, Perry CJ, Scanlan DJ, Taylor PC. The evolutionary origins of peroxynitrite signalling. Biochem Biophys Res Commun 2021; 580:107-112. [PMID: 34638028 DOI: 10.1016/j.bbrc.2021.09.071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/24/2021] [Accepted: 09/25/2021] [Indexed: 12/13/2022]
Abstract
Peroxynitrite is a reactive intermediate formed in vivo through uncatalysed reaction of superoxide and nitric oxide radicals. Despite significant interest in detecting peroxynitrite in vivo and understanding its production, little attention has been given to the evolutionary origins of peroxynitrite signalling. Herein we focus on two enzymes that are key to the biosynthesis of superoxide and nitric oxide, NADPH oxidase 5 (NOX5) and endothelial nitric oxide synthase (eNOS), respectively. Multiple sequence alignments of both enzymes including homologues from all domains of life, coupled with a phylogenetic analysis of NOX5, suggest eNOS and NOX5 are present in animals as the result of horizontal gene transfer from ancestral cyanobacteria to ancestral eukaryotes. Therefore, biochemical studies from other laboratories on a NOX5 homologue in Cylindrospermum stagnale and an eNOS homologue in Synechococcus sp. PCC 7335 are likely to be of relevance to human NOX5 and eNOS and to the production of superoxide, nitric oxide and peroxynitrite in humans.
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Affiliation(s)
- Jennifer A Miles
- School of Chemistry & Astbury Centre, University of Leeds, Leeds, LS2 9JT, UK
| | - Joseph L Egan
- School of Chemistry & Astbury Centre, University of Leeds, Leeds, LS2 9JT, UK
| | - Jake A Fowler
- School of Chemistry & Astbury Centre, University of Leeds, Leeds, LS2 9JT, UK
| | - Petrina Machattou
- School of Chemistry & Astbury Centre, University of Leeds, Leeds, LS2 9JT, UK
| | - Andrew D Millard
- Dept. of Genome Biology & Genetics, University of Leicester, Leicester, LE1 7RH, UK
| | | | - David J Scanlan
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Paul C Taylor
- School of Chemistry & Astbury Centre, University of Leeds, Leeds, LS2 9JT, UK.
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Mohis M, Edwards S, Ryan S, Rizvi F, Tajik AJ, Jahangir A, Ross GR. Aging-related increase in store-operated Ca 2+ influx in human ventricular fibroblasts. Am J Physiol Heart Circ Physiol 2019; 315:H83-H91. [PMID: 29985070 DOI: 10.1152/ajpheart.00588.2017] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Senescence-related fibrosis contributes to cardiac dysfunction. Profibrotic processes are Ca2+ dependent. The effect of aging on the Ca2+ mobilization processes of human ventricular fibroblasts (hVFs) is unclear. Therefore, we tested whether aging altered intracellular Ca2+ release and store-operated Ca2+ entry (SOCE). Disease-free hVFs from 2- to 63-yr-old trauma victims were assessed for cytosolic Ca2+ dynamics with fluo 3/confocal imaging. Angiotensin II or thapsigargin was used to release endoplasmic reticulum Ca2+ in Ca2+-free solution; CaCl2 (2 mM) was then added to assess SOCE, which was normalized to ionomycin-induced maximal Ca2+. The angiotensin II experiments were repeated after phosphoenolpyruvate pretreatment to determine the role of energy status. The expression of genes encoding SOCE-related ion channel subunits was assessed by quantitative PCR, and protein expression was assessed by immunoblot analysis. Age groups of <50 and ≥50 yr were compared using unpaired t-test or regression analysis. Ca2+ release by angiotensin II or thapsigargin was not different between the groups, but SOCE was significantly elevated in the ≥50-yr group. Regression analysis showed an age-dependent phosphoenolpyruvate-sensitive increase in SOCE of hVFs. Aging did not alter the mRNA expression of SOCE-related genes. The profibrotic phenotype of hVFs was evident by sprouty1 downregulation with age. Thus, an age-associated increase in angiotensin II- and thapsigargin-induced SOCE occurs in hVFs, independent of receptor mechanisms or alterations of mRNA expression level of SOCE-related ion channel subunits but related to the cellular bioenergetics status. Elucidation of mechanisms underlying enhanced hVF SOCE with aging may refine SOCE targets to limit aging-related progression of Ca2+-dependent cardiac fibrosis. NEW & NOTEWORTHY Human ventricular fibroblasts exhibit an age-related increase in store-operated Ca2+ influx induced by angiotensin II, an endogenous vasoactive hormone, or thapsigargin, an inhibitor of endoplasmic reticulum Ca2+-ATPase, independent of receptor mechanisms or genes encoding store-operated Ca2+ entry-related ion channel subunits. Selective inhibition of this augmented store-operated Ca2+ entry could therapeutically limit aging-related cardiac fibrosis.
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Affiliation(s)
- Momin Mohis
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin
| | - Stacie Edwards
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin
| | - Sean Ryan
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin
| | - Farhan Rizvi
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin
| | - A Jamil Tajik
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin.,Aurora Cardiovascular Services, Aurora Sinai/Aurora St. Luke's Medical Centers , Milwaukee, Wisconsin
| | - Arshad Jahangir
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin.,Aurora Cardiovascular Services, Aurora Sinai/Aurora St. Luke's Medical Centers , Milwaukee, Wisconsin
| | - Gracious R Ross
- Center for Integrative Research on Cardiovascular Aging, Aurora Research Institute, Aurora Health Care, Milwaukee, Wisconsin
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Dihydrotanshinone-Induced NOX5 Activation Inhibits Breast Cancer Stem Cell through the ROS/Stat3 Signaling Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:9296439. [PMID: 31019654 PMCID: PMC6451810 DOI: 10.1155/2019/9296439] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 11/14/2018] [Indexed: 12/14/2022]
Abstract
Cancer stem cells (CSCs) are known to mediate metastasis and recurrence and are therefore a promising therapeutic target. In this study, we found that dihydrotanshinone (DHTS) inhibits CSC formation. DHTS inhibited mammosphere formation in a dose-dependent manner and showed significant tumor growth inhibition in a xenograft model. This compound reduced the CD44high/CD24low- and aldehyde dehydrogenase- (ALDH-) expressing cell population and the self-renewal-related genes Nanog, SOX2, OCT4, C-Myc, and CD44. DHTS induced NOX5 activation by increasing calcium, and NOX5 activation induced reactive oxygen species (ROS) production. ROS production reduced the nuclear phosphorylation levels of Stat3 and secreted IL-6 levels in the mammospheres. DHTS deregulated the dynamic equilibrium from non-stem cancer cells to CSCs by dephosphorylating Stat3 and decreasing IL-6 secretion and inhibiting CSC formation. These novel findings showed that DHTS-induced ROS deregulated the Stat3/IL-6 pathway and induced CSC death. NOX5 activation by DHTS inhibits CSC formation through ROS/Stat3/IL-6 signaling, and DHTS may be a promising potential therapeutic agent against breast CSCs.
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Abstract
SIGNIFICANCE G protein-coupled receptors (GPCR) are the largest group of cell surface receptors, which link cells to their environment. Reactive oxygen species (ROS) can act as important cellular signaling molecules. The family of NADPH oxidases generates ROS in response to activated cell surface receptors. Recent Advances: Various signaling pathways linking GPCRs and activation of NADPH oxidases have been characterized. CRITICAL ISSUES Still, a more detailed analysis of G proteins involved in the GPCR-mediated activation of NADPH oxidases is needed. In addition, a more precise discrimination of NADPH oxidase activation due to either upregulation of subunit expression or post-translational subunit modifications is needed. Also, the role of noncanonical modulators of NADPH oxidase activation in the response to GPCRs awaits further analyses. FUTURE DIRECTIONS As GPCRs are one of the most popular classes of investigational drug targets, further detailing of G protein-coupled mechanisms in the activation mechanism of NADPH oxidases as well as better understanding of the link between newly identified NADPH oxidase interaction partners and GPCR signaling will provide new opportunities for improved efficiency and decreased off target effects of therapies targeting GPCRs.
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Affiliation(s)
- Andreas Petry
- 1 Experimental and Molecular Pediatric Cardiology, German Heart Center Munich , TU Munich, Munich, Germany
| | - Agnes Görlach
- 1 Experimental and Molecular Pediatric Cardiology, German Heart Center Munich , TU Munich, Munich, Germany .,2 DZHK (German Centre for Cardiovascular Research) , Partner Site Munich, Munich Heart Alliance, Munich, Germany
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Tseng HC, Lin CC, Wang CY, Yang CC, Hsiao LD, Yang CM. Lysophosphatidylcholine induces cyclooxygenase-2-dependent IL-6 expression in human cardiac fibroblasts. Cell Mol Life Sci 2018; 75:4599-4617. [PMID: 30229288 PMCID: PMC11105650 DOI: 10.1007/s00018-018-2916-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Revised: 08/08/2018] [Accepted: 09/04/2018] [Indexed: 02/07/2023]
Abstract
Lysophosphatidylcholine (LysoPC) has been shown to induce the expression of inflammatory proteins, including cyclooxygenase-2 (COX-2) and interleukin-6 (IL-6), associated with cardiac fibrosis. Here, we demonstrated that LysoPC-induced COX-2 and IL-6 expression was inhibited by silencing NADPH oxidase 1, 2, 4, 5; p65; and FoxO1 in human cardiac fibroblasts (HCFs). LysoPC-induced IL-6 expression was attenuated by a COX-2 inhibitor. LysoPC-induced responses were mediated via the NADPH oxidase-derived reactive oxygen species-dependent JNK1/2 phosphorylation pathway, leading to NF-κB and FoxO1 activation. In addition, we demonstrated that both FoxO1 and p65 regulated COX-2 promoter activity stimulated by LysoPC. Overexpression of wild-type FoxO1 and S256D FoxO1 enhanced COX-2 promoter activity and protein expression in HCFs. These results were confirmed by ex vivo studies, where LysoPC-induced COX-2 and IL-6 expression was attenuated by the inhibitors of NADPH oxidase, NF-κB, and FoxO1. Our findings demonstrate that LysoPC-induced COX-2 expression is mediated via NADPH oxidase-derived reactive oxygen species generation linked to the JNK1/2-dependent pathway leading to FoxO1 and NF-κB activation in HCFs. LysoPC-induced COX-2-dependent IL-6 expression provided novel insights into the therapeutic targets of the cardiac fibrotic responses.
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Affiliation(s)
- Hui-Ching Tseng
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-San, Tao-Yuan, Taiwan
- Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chih-Chung Lin
- Department of Anesthetics, Chang Gung Memorial Hospital at Linkuo and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chen-Yu Wang
- Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chien-Chung Yang
- Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital at Tao-Yuan, Kwei-San, Tao-Yuan, Taiwan
- School of Traditional Chinese Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Li-Der Hsiao
- Department of Anesthetics, Chang Gung Memorial Hospital at Linkuo and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan
| | - Chuen-Mao Yang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, 259 Wen-Hwa 1st Road, Kwei-San, Tao-Yuan, Taiwan.
- Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan.
- Department of Anesthetics, Chang Gung Memorial Hospital at Linkuo and Chang Gung University, Kwei-San, Tao-Yuan, Taiwan.
- Research Center for Chinese Herbal Medicine and Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Tao-Yuan, Taiwan.
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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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NADPH Oxidases: Insights into Selected Functions and Mechanisms of Action in Cancer and Stem Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017. [PMID: 28626501 PMCID: PMC5463201 DOI: 10.1155/2017/9420539] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
NADPH oxidases (NOX) are reactive oxygen species- (ROS-) generating enzymes regulating numerous redox-dependent signaling pathways. NOX are important regulators of cell differentiation, growth, and proliferation and of mechanisms, important for a wide range of processes from embryonic development, through tissue regeneration to the development and spread of cancer. In this review, we discuss the roles of NOX and NOX-derived ROS in the functioning of stem cells and cancer stem cells and in selected aspects of cancer cell physiology. Understanding the functions and complex activities of NOX is important for the application of stem cells in tissue engineering, regenerative medicine, and development of new therapies toward invasive forms of cancers.
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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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Kao L, Azimov R, Abuladze N, Newman D, Kurtz I. Human SLC4A11-C functions as a DIDS-stimulatable H⁺(OH⁻) permeation pathway: partial correction of R109H mutant transport. Am J Physiol Cell Physiol 2014; 308:C176-88. [PMID: 25394471 DOI: 10.1152/ajpcell.00271.2014] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The SLC4A11 gene mutations cause a variety of genetic corneal diseases, including congenital hereditary endothelial dystrophy 2 (CHED2), Harboyan syndrome, some cases of Fuchs' endothelial dystrophy (FECD), and possibly familial keratoconus. Three NH2-terminal variants of the human SLC4A11 gene, named SLC4A11-A, -B, and -C are known. The SLC4A11-B variant has been the focus of previous studies. Both the expression of the SLC4A11-C variant in the cornea and its functional properties have not been characterized, and therefore its potential pathophysiological role in corneal diseases remains to be explored. In the present study, we demonstrate that SLC4A11-C is the predominant SLC4A11 variant expressed in human corneal endothelial mRNA and that the transporter functions as an electrogenic H(+)(OH(-)) permeation pathway. Disulfonic stilbenes, including 4,4'-diisothiocyano-2,2'-stilbenedisulfonate (DIDS), 4,4'-diisothiocyanatodihydrostilbene-2,2'-disulfonate (H2DIDS), and 4-acetamido-4'-isothiocyanato-stilbene-2,2'-disulfonate (SITS), which are known to bind covalently, increased SLC4A11-C-mediated H(+)(OH(-)) flux by 150-200% without having a significant effect in mock-transfected cells. Noncovalently interacting 4,4'-diaminostilbene-2,2'-disulfonate (DADS) was without effect. We tested the efficacy of DIDS on the functionally impaired R109H mutant (SLC4A11-C numbering) that causes CHED2. DIDS (1 mM) increased H(+)(OH(-)) flux through the mutant transporter by ∼40-90%. These studies provide a basis for future testing of more specific chemically modified dilsulfonic stilbenes as potential therapeutic agents to improve the functional impairment of specific SLC4A11 mutant transporters.
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Affiliation(s)
- Liyo Kao
- Division of Nephrology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; and
| | - Rustam Azimov
- Division of Nephrology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; and
| | - Natalia Abuladze
- Division of Nephrology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; and
| | - Debra Newman
- Division of Nephrology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; and
| | - Ira Kurtz
- Division of Nephrology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California; and Brain Research Institute, University of California Los Angeles, Los Angeles, California
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Abstract
NADPH oxidase5 (Nox5) is a novel Nox isoform which has recently been recognized as having important roles in the pathogenesis of coronary artery disease, acute myocardial infarction, fetal ventricular septal defect and cancer. The activity of Nox5 and production of reactive oxygen species is regulated by intracellular calcium levels and phosphorylation. However, the kinases that phosphorylate Nox5 remain poorly understood. Previous studies have shown that the phosphorylation of Nox5 is PKC dependent, but this contention was based on the use of pharmacological inhibitors and the isoforms of PKC involved remain unknown. Thus, the major goals of this study were to determine whether PKC can directly regulate Nox5 phosphorylation and activity, to identify which isoforms are involved in the process, and to understand the functional significance of this pathway in disease. We found that a relatively specific PKCα inhibitor, Ro-32-0432, dose-dependently inhibited PMA-induced superoxide production from Nox5. PMA-stimulated Nox5 activity was significantly reduced in cells with genetic silencing of PKCα and PKCε, enhanced by loss of PKCδ and the silencing of PKCθ expression was without effect. A constitutively active form of PKCα robustly increased basal and PMA-stimulated Nox5 activity and promoted the phosphorylation of Nox5 on Ser490, Thr494, and Ser498. In contrast, constitutively active PKCε potently inhibited both basal and PMA-dependent Nox5 activity. Co-IP and in vitro kinase assay experiments demonstrated that PKCα directly binds to Nox5 and modifies Nox5 phosphorylation and activity. Exposure of endothelial cells to high glucose significantly increased PKCα activation, and enhanced Nox5 derived superoxide in a manner that was in prevented by a PKCα inhibitor, Go 6976. In summary, our study reveals that PKCα is the primary isoform mediating the activation of Nox5 and this maybe of significance in our understanding of the vascular complications of diabetes and other diseases with increased ROS production.
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Weyemi U, Redon CE, Parekh PR, Dupuy C, Bonner WM. NADPH Oxidases NOXs and DUOXs as putative targets for cancer therapy. Anticancer Agents Med Chem 2013; 13:502-514. [PMID: 22931418 PMCID: PMC6365101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2012] [Revised: 07/03/2012] [Accepted: 07/23/2012] [Indexed: 06/01/2023]
Abstract
Reactive oxygen species (ROS) form a class of molecules with both positive and negative impacts on cellular health. Negatively, ROS may react with cellular constituents including proteins, lipids, and DNA to generate an array of oxidative lesions. These lesions may compromise genome stability which is critical for long-term cellular homeostasis and healthy progeny. Paradoxically, ROS also function as strong signalling molecules that mediate various growth-related responses, so their presence is also essential for cellular metabolism. While ROS are generated in an unregulated manner by physical stresses such as exposure to ionizing radiation and biochemical malfunctions such as mitochondrial leakage, cells also contain the NADPH oxidases NOXs and DUOXs, which specifically generate ROS in a wide variety of tissues. While the NOXs/DUOXs may be involved in maintaining optimal cellular redox levels, there is also accumulating evidence that NADPH oxidases-derived ROS may elevate the risk for genomic instability and cancer. Cancer cells may produce high levels of ROS, and in some cases, the source of these ROS has been linked to NOX/DUOX deregulation as reported for prostate cancer (NOX1 and NOX5), melanoma and glioblastoma (NOX4) among others. In addition, recent studies reveal that targeting NADPH oxidases with NOXs inhibitors may impair tumor growth in vivo; indicating that these proteins may be useful targets in future clinical strategies to fight cancer. This review provides an overview of the current knowledge concerning these enzymes, their roles in cancer, and their potential as targets in future cancer therapies.
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Affiliation(s)
- Urbain Weyemi
- Laboratory of Molecular Pharmacology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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