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Miyazawa H, Muraoka M, Matsuda Y, Toma T, Morio T, Shigemura T, Haraguchi K, Matsubayashi T, Kawai T, Shirai Y, Wada T. Clinical and molecular significance of flow cytometric analysis for reactive oxygen species production and residual p67 phox expression in p67 phox-deficient chronic granulomatous disease. Scand J Immunol 2024:e13372. [PMID: 38654426 DOI: 10.1111/sji.13372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 02/23/2024] [Accepted: 03/30/2024] [Indexed: 04/26/2024]
Abstract
Chronic granulomatous disease (CGD) is a primary immunodeficiency disease caused by molecular defects in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. p67phox-CGD is an autosomal recessive CGD, which is caused by a defect in the cytosolic components of NADPH oxidase, p67phox, encoded by NCF2. We previously established a flow cytometric analysis for p67phox expression, which allows accurate assessment of residual protein expression in p67phox-CGD. We evaluated the correlation between oxidase function and p67phox expression, and assessed the relevancy to genotypes and clinical phenotypes in 11 patients with p67phox-CGD. Reactive oxygen species (ROS) production by granulocytes was evaluated using dihydrorhodamine-1,2,3 (DHR) assays. p67phox expression was evaluated in the monocyte population. DHR activity and p67phox expression were significantly correlated (r = 0.718, p < 0.0162). Additionally, DHR activity and p67phox expression were significantly higher in patients carrying one missense variant in combination with one nonsense or frameshift variant in the NCF2 gene than in patients with only null variants. The available clinical parameters of our patients (i.e., age at disease onset, number of infectious episodes, and each infection complication) were not linked with DHR activity or p67phox expression levels. In summary, our flow cytometric analysis revealed a significant correlation between residual ROS production and p67phox expression. More deleterious NCF2 genotypes were associated with lower levels of DHR activity and p67phox expression. DHR assays and protein expression analysis by using flow cytometry may be relevant strategies for predicting the genotypes of p67phox-CGD.
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Affiliation(s)
- Hanae Miyazawa
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Masahiro Muraoka
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Yusuke Matsuda
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Tomoko Toma
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
| | - Tomohiro Morio
- Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Tokyo, Japan
| | - Tomonari Shigemura
- Department of Pediatrics, Shinshu University School of Medicine, Matsumoto, Japan
| | - Kohei Haraguchi
- Department of Pediatrics, Nagasaki University Hospital, Nagasaki, Japan
| | | | - Toshinao Kawai
- Division of Immunology, National Center for Child Health and Development, Tokyo, Japan
| | - Yuya Shirai
- Department of Respiratory Medicine and Clinical Immunology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Taizo Wada
- Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan
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Liu ZM, Shen PC, Lu CC, Chou SH, Tien YC. Suramin enhances chondrogenic properties by regulating the p67 phox/PI3K/AKT/SOX9 signalling pathway. Bone Joint Res 2022; 11:723-738. [PMID: 36222195 PMCID: PMC9582866 DOI: 10.1302/2046-3758.1110.bjr-2022-0013.r2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Aims Autologous chondrocyte implantation (ACI) is a promising treatment for articular cartilage degeneration and injury; however, it requires a large number of human hyaline chondrocytes, which often undergo dedifferentiation during in vitro expansion. This study aimed to investigate the effect of suramin on chondrocyte differentiation and its underlying mechanism. Methods Porcine chondrocytes were treated with vehicle or various doses of suramin. The expression of collagen, type II, alpha 1 (COL2A1), aggrecan (ACAN); COL1A1; COL10A1; SRY-box transcription factor 9 (SOX9); nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX); interleukin (IL)-1β; tumour necrosis factor alpha (TNFα); IL-8; and matrix metallopeptidase 13 (MMP-13) in chondrocytes at both messenger RNA (mRNA) and protein levels was determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot. In addition, the supplementation of suramin to redifferentiation medium for the culture of expanded chondrocytes in 3D pellets was evaluated. Glycosaminoglycan (GAG) and collagen production were evaluated by biochemical analyses and immunofluorescence, as well as by immunohistochemistry. The expression of reactive oxygen species (ROS) and NOX activity were assessed by luciferase reporter gene assay, immunofluorescence analysis, and flow cytometry. Mutagenesis analysis, Alcian blue staining, reverse transcriptase polymerase chain reaction (RT-PCR), and western blot assay were used to determine whether p67phox was involved in suramin-enhanced chondrocyte phenotype maintenance. Results Suramin enhanced the COL2A1 and ACAN expression and lowered COL1A1 synthesis. Also, in 3D pellet culture GAG and COL2A1 production was significantly higher in pellets consisting of chondrocytes expanded with suramin compared to controls. Surprisingly, suramin also increased ROS generation, which is largely caused by enhanced NOX (p67phox) activity and membrane translocation. Overexpression of p67phox but not p67phoxAD (deleting amino acid (a.a) 199 to 212) mutant, which does not support ROS production in chondrocytes, significantly enhanced chondrocyte phenotype maintenance, SOX9 expression, and AKT (S473) phosphorylation. Knockdown of p67phox with its specific short hairpin (sh) RNA (shRNA) abolished the suramin-induced effects. Moreover, when these cells were treated with the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) inhibitor LY294002 or shRNA of AKT1, p67phox-induced COL2A1 and ACAN expression was significantly inhibited. Conclusion Suramin could redifferentiate dedifferentiated chondrocytes dependent on p67phox activation, which is mediated by the PI3K/AKT/SOX9 signalling pathway. Cite this article: Bone Joint Res 2022;11(10):723–738.
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Affiliation(s)
- Zi-Miao Liu
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Po-Chih Shen
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Cheng-Chang Lu
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan,Department of Orthopedics, Faculty of Medical School, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan,Department of Orthopaedic Surgery, Kaohsiung Municipal Siaogang Hospital, Kaohsiung, Taiwan,Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Shih-Hsiang Chou
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yin-Chun Tien
- Department of Orthopedics, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan,Department of Orthopedics, Faculty of Medical School, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan, Yin-Chun Tien. E-mail:
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Zhao L, Zhang R, Zhang S, Zhang H, Yang Q, Xu Z. Upregulation of p67 phox in response to ischemia/reperfusion is cardioprotective by increasing ZIP2 expression via STAT3. Free Radic Res 2022; 56:115-126. [PMID: 35296207 DOI: 10.1080/10715762.2022.2052057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
While the zinc transporter ZIP2 (Slc39a2) is upregulated via STAT3 as an adaptive response to protect the heart from ischemia/reperfusion (I/R) injury, the precise mechanism underlying its upregulation remains unclear. The purpose of this study was to investigate the role of NADPH oxidase (NOX) isoform NOX2-derived ROS in the regulation of ZIP2 expression, focusing on the role of the NOX2 cytosolic factor p67phox. Mouse hearts or H9c2 cells were subjected to I/R. Protein expression was detected with Western blotting. Infarct size was measured with TTC staining. The cardiac-specific p67phox conditional knockout mice (p67phox cKO) were generated by adopting the CRISPR/Cas9 system. I/R-induced upregulation of STAT3 phosphorylation and ZIP2 expression was reversed by the ROS scavenger N-acetylcysteine (NAC) and the NOX inhibitor diphenyleneiodonium (DPI). p67phox but not NOX2 expression was increased 30 min after the onset of reperfusion, and downregulation of p67phox by siRNA or cKO invalidated I/R-induced upregulation of STAT3 phosphorylation and ZIP2 expression. Both NAC and DPI prevented upregulation of STAT3 phosphorylation and ZIP2 expression induced by overexpression of p67phox, whereas the STAT3 inhibitor stattic abrogated upregulation ZIP2 expression, indicating that the increase of p67phox at reperfusion is an upstream signaling event responsible for ZIP2 upregulation via STAT3. Experiments also showed that chelation of Zn2+ markedly enhanced p67phox and ZIP2 expression as well as STAT3 phosphorylation, whereas supplementation of Zn2+ had the opposite effects, indicating that cardiac Zn2+ loss upon reperfusion triggers p67phox upregulation. Furthermore, ischemic preconditioning (IPC) upregulated ZIP2 via p67phox, and cKO of p67phox aggravated cardiac injury after I/R, indicating that p67phox upregulation is cardioprotective against I/R injury. In conclusion, an increase of p67phox expression in response to Zn2+ is an intrinsic adaptive response to I/R and leads to cardioprotection against I/R by upregulating ZIP2 via STAT3.
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Affiliation(s)
- Liang Zhao
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Rui Zhang
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Shuya Zhang
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Hualu Zhang
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China
| | - Qing Yang
- Department of Cardiology, General Hospital, Tianjin Medical University, Tianjin, China
| | - Zhelong Xu
- Department of Physiology and Pathophysiology, Tianjin Medical University, Tianjin, China.,Department of Cardiology, General Hospital, Tianjin Medical University, Tianjin, China
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Martínez MA, Úbeda A, Trillo MÁ. Role of NADPH oxidase in MAPK signaling activation by a 50 Hz magnetic field in human neuroblastoma cells. Electromagn Biol Med 2020; 40:103-116. [PMID: 33345643 DOI: 10.1080/15368378.2020.1851250] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Our previous studies have shown that intermittent exposure to a 50-Hz, 100-µT sine wave magnetic field (MF) promotes human NB69 cell proliferation, mediated by activation of the epidermal growth factor receptor (EGFR) and pathways MAPK-ERK1/2 and p38; being the effects on proliferation and p38 activation blocked by the chelator N-acetylcysteine. The present work investigates the MF effects on free radical (FR) production, and the potential involvement of NADPH oxidase, the main source of reactive oxygen species (ROS), in the MF-induced activation of MAPK pathways. To this end, the field effects on MAPK-ERK1/2, -p38 and -JNK activation in the presence or absence of the NADPH oxidase inhibitor, diphenyleneiodonium chloride (DPI), as well as the expression of the p67phox subunit, were analyzed. The results revealed that field exposure increases FR production and induces early, transient expression of the cytosolic component of the NADPH oxidase, p67phox. Also, the MF-induced activation of the MAPK-JNK pathway, but not that of -ERK1/2 or -p38 pathways, was prevented in the presence of the DPI, which has been shown to significantly reduce p67phox expression. These data, together with those from previous studies, identify various, FR-dependent or -independent mechanisms, involved in the MF-induced proliferative response mediated by MAPK signaling activation.
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Affiliation(s)
| | - Alejandro Úbeda
- Servicio BEM, Dept. Investigación, Hosp, Univ. Ramón Y Cajal- IRYCIS , Madrid, Spain
| | - María Ángeles Trillo
- Servicio BEM, Dept. Investigación, Hosp, Univ. Ramón Y Cajal- IRYCIS , Madrid, Spain
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Zheng K, Hao J, Xiao L, Wang M, Zhao Y, Fan D, Li Y, Wang X, Zhang L. Expression of nicotinamide adenine dinucleotide phosphate oxidase in chronic rhinosinusitis with nasal polyps. Int Forum Allergy Rhinol 2020; 10:646-655. [PMID: 32052917 DOI: 10.1002/alr.22530] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 11/30/2019] [Accepted: 01/03/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase produces reactive oxygen species (ROS) involved in oxidative stress and signal transduction. Recent studies have suggested that NADPH oxidase is associated with the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). The aim of this study was to detect the expression of NADPH oxidase subunits and 4-hydroxynonenal (4-HNE) in nasal polyp tissue and normal nasal mucosa, in order to explore the possible role played by NADPH oxidase in the pathogenesis of CRSwNP. METHODS Thirteen patients with CRSwNP and 9 normal control subjects were selected to participate in this study, in which we evaluated the expression of different NADPH oxidase subunits (gp91phox , p67phox , p47phox , and p22phox ) in nasal polyp (NP) tissue and control mucosa by Western blotting and real-time polymerase chain reaction (PCR). Immunohistochemistry and immunofluorescence staining were used to detect expression of the p67phox subunit and 4-HNE in NP tissue and normal nasal mucosa. RESULTS Western blot and real-time PCR results showed that p67phox expression was significantly increased in NP tissue when compared with its expression in control mucosa (p = 0.004). p67phox was expressed in the eosinophils and neutrophils found in NP tissue, but not in the macrophages. Additionally, the levels of 4-HNE expression were also significantly increased in NP tissue when compared with control mucosa (p = 0.001). CONCLUSION The levels of p67phox messenger RNA (mRNA) and protein as well as 4-HNE were both upregulated in NP tissue, suggesting that p67phox and oxidative stress play roles in the pathogenesis of CRSwNP.
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Affiliation(s)
- Kaili Zheng
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Jin Hao
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China
| | - Lei Xiao
- Department of Medicine, University of Illinois at Chicago, Chicago, IL
| | - Min Wang
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Yan Zhao
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Dachuan Fan
- Department of Otolaryngology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Ying Li
- Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Xiangdong Wang
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
| | - Luo Zhang
- Department of Otolaryngology Head and Neck Surgery, Department of Allergy, Beijing TongRen Hospital, Key Laboratory of Otolaryngology Head and Neck Surgery, Ministry of Education, Capital Medical University, Beijing, China.,Beijing Key Laboratory of Nasal Diseases, Beijing Institute of Otolaryngology, Beijing, China
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Abais-Battad JM, Lund H, Dasinger JH, Fehrenbach DJ, Cowley AW, Mattson DL. NOX2-derived reactive oxygen species in immune cells exacerbates salt-sensitive hypertension. Free Radic Biol Med 2020; 146:333-339. [PMID: 31730933 PMCID: PMC6942201 DOI: 10.1016/j.freeradbiomed.2019.11.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 10/29/2019] [Accepted: 11/11/2019] [Indexed: 12/11/2022]
Abstract
Previous studies utilizing the SSp67phox-/- rat have demonstrated the importance of systemic NADPH oxidase NOX2-derived reactive oxygen species (ROS) production in the pathogenesis of Dahl Salt-Sensitive (SS) hypertension and renal damage. It is established that the immune system contributes to the development of SS hypertension and our laboratory has observed an enrichment of NOX2 subunits in infiltrating T cells. However, the contribution of immune cell-derived ROS in SS hypertension remains unknown. To assess the role of ROS in immune cells, SSp67phox-/- rats underwent total body irradiation and received bone marrow transfer from either SS (+SS) or SSp67phox-/- (+SSp67phox-/-) donor rats. Demonstrated in a respiratory burst assay, response to phorbol 12-myristate 13-acetate stimulus (135 μM) was 10.2-fold greater in peritoneal macrophages isolated from +SS rats compared to nonresponsive + SSp67phox-/- cells, validating that + SS rats were capable of producing NOX2-derived ROS in cells of hematopoietic origin. After 3 weeks of high salt challenge, there was an exacerbated increase in mean arterial pressure in +SS rats compared to + SSp67phox-/- control rats (176.1 ± 4.7 vs 147.9 ± 8.4 mmHg, respectively), which was accompanied by a significant increase in albuminuria (168.3 ± 23.7 vs 107.0 ± 20.4 mg/day) and renal medullary protein cast formation (33.2 ± 4.7 vs 8.1 ± 3.5%). Interestingly, upon analysis of renal immune cells, there was trending increase of CD11b/c + monocytes and macrophages in the kidney of +SS rats (4.7 ± 0.4 vs 3.5 ± 0.5 × 106 cells/kidney, +SS vs + SSp67phox-/-, p = 0.06). These data altogether demonstrate that immune cell production of NOX2-derived ROS is sufficient to exacerbate Dahl SS hypertension, renal damage, and renal inflammation.
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Affiliation(s)
- Justine M Abais-Battad
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA.
| | - Hayley Lund
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - John Henry Dasinger
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Daniel J Fehrenbach
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - Allen W Cowley
- Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
| | - David L Mattson
- Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA; Department of Physiology, Medical College of Georgia at Augusta University, Augusta, GA, USA
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Abstract
The superoxide (O2·-)-generating NADPH oxidase complex of phagocytes comprises a membrane-associated heterodimeric flavocytochrome, known as cytochrome b 558 (consisting of NOX2 and p22phox) and four cytosolic regulatory proteins, p47phox, p67phox, p40phox, and the small GTPase Rac. Under physiological conditions, in the resting phagocyte, O2·- generation is initiated by engagement of membrane receptors by a variety of stimuli, followed by signal transduction sequences leading to the translocation of the cytosolic components to the membrane and their association with the cytochrome, a process known as NADPH oxidase assembly. A consequent conformational change in NOX2 initiates the electron flow along a redox gradient, from NADPH to molecular oxygen (O2), leading to the one-electron reduction of O2 to O2·-. Historically, methodological difficulties in the study of the assembled complex derived from stimulated cells, due to its lack of stability, led to the design of "cell-free" systems (also known as "broken cells" or in vitro systems). In a major paradigm shift, the cell-free systems have as their starting point NADPH oxidase components derived from resting (unstimulated) phagocytes, or as in the predominant method at present, recombinant proteins representing the components of the NADPH oxidase complex. In cell-free systems, membrane receptor stimulation and the signal transduction sequence are absent, the accent being placed on the actual process of assembly, all of which takes place in vitro. Thus, a mixture of the individual components of the NADPH oxidase is exposed in vitro to an activating agent, the most common being anionic amphiphiles, resulting in the formation of a complex between cytochrome b 558 and the cytosolic components and O2·- generation in the presence of NADPH. Alternative activating pathways require posttranslational modification of oxidase components or modifying the phospholipid milieu surrounding cytochrome b 558. Activation is commonly quantified by measuring the primary product of the reaction, O2·-, trapped immediately after its generation by an appropriate acceptor in a kinetic assay, permitting the calculation of rates of O2·- production, but numerous variations exist, based on the assessment of reaction products or the consumption of substrates. Cell-free assays played a paramount role in the identification and characterization of the components of the NADPH oxidase complex, the performance of structure-function studies, the deciphering of the mechanisms of assembly, the search for inhibitory drugs, and the diagnosis of various forms of chronic granulomatous disease (CGD).
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Abstract
Neutrophils serve as the circulating cells that respond early and figure prominently in human host defense to infection and in inflammation in other settings. Optimal oxidant-dependent antimicrobial activity by neutrophils relies on the ability of stimulated phagocytes to utilize a multicomponent NADPH oxidase to generate oxidants. The frequent, severe, and often fatal infections experienced by individuals with chronic granulomatous disease (CGD), an inherited disorder in which one of the NADPH oxidase components is absent or dysfunctional, underscore the link between a functional phagocyte NADPH oxidase and robust host protection against microbial infection.The history of the discovery and characterization of the normal neutrophil NADPH oxidase and the saga of recognizing CGD and its underlying causes together illustrate how the observations of astute clinicians and imaginative basic scientists synergize to forge new understanding of both basic cell biology and pathogenesis of human disease.In this chapter, we review the events in the stepwise evolution of our understanding of the phagocyte NADPH oxidase, both in the context of normal human neutrophil function and in the setting of CGD. The phagocyte oxidase complex employs a heterodimeric transmembrane protein composed of gp91phox and p22phox to relay electrons from NADPH to molecular oxygen, while other cofactors contribute to localization and regulation of the activity of the assembled oxidase. The b-type cytochrome gp91phox, also known as NOX2, serves as the catalytic component of this multicomponent enzyme complex. Although many of the features of the composition and regulation of the phagocyte oxidase may apply as well to NOX2 expressed in non-phagocytes and to other members of the NOX protein family, exceptions exist and pose special challenges to investigators exploring the biology of NADPH oxidases.
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Affiliation(s)
- William M Nauseef
- Inflammation Program, Department of Medicine, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Robert A Clark
- Institute for Integration of Medicine and Science and Department of Medicine, University of Texas Health Science Center, and South Texas Veterans Healthcare System, San Antonio, TX, USA.
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Abstract
NOX family NADPH oxidases deliberately produce reactive oxygen species and thus contribute to a variety of biological functions. Of seven members in the human family, the three oxidases NOX2, NOX1, and NOX3 form a heterodimer with p22phox and are regulated by soluble regulatory proteins: p47phox, its related organizer NOXO1; p67phox, its related activator NOXA1; p40phox; and the small GTPase Rac. Activation of the phagocyte oxidase NOX2 requires p47phox, p67phox, and GTP-bound Rac. In addition to these regulators, p40phox plays a crucial role when NOX2 is activated during phagocytosis. On the other hand, NOX1 activation prefers NOXO1 and NOXA1, although Rac is also involved. NOX3 constitutively produces superoxide, which is enhanced by regulatory proteins such as p47phox, NOXO1, and p67phox. Here we describe mechanisms for NOX activation with special attention to the soluble regulatory proteins.
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Affiliation(s)
- Hideki Sumimoto
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
| | - Reiko Minakami
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Kei Miyano
- Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
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10
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Abstract
The NADPH oxidase complex, responsible for reactive oxygen species (ROS) generation by phagocytes, consists of a membrane-associated flavocytochrome b 558 (a heterodimer of NOX2 and p22phox) and the cytosolic components p47phox, p67phox, Rac(1 or 2), and p40phox. NOX2 carries all redox stations through which electrons flow from NADPH to molecular oxygen, to generate the primary ROS, superoxide. For the electron flow to start, a conformational change in NOX2 is required. The dominant hypothesis is that this change is the result of the interaction of NOX2 with one or more of the cytosolic components (NADPH oxidase assembly). At the most basic level, assembly is the sum of several protein-protein interactions among oxidase components. This chapter describes a reductionist approach to the identification of regions in oxidase components involved in assembly. This approach consists of "transforming" one component in an array of overlapping synthetic peptides and assessing binding to the peptides of another component, represented by a recombinant protein. The peptides are tagged with biotin, at the N- or C-terminus, and immobilized on streptavidin-coated 96-well plates. The protein partners are expressed with a 6His tag and added to the plates in the fluid phase. Binding of the protein to the peptides is quantified by a kinetic ELISA , using a peroxidase-conjugated anti-polyhistidine antibody. Protein-peptide binding assays were applied successfully to (a) identifying the binding site on one component (represented by peptides) for another component (proteins), (b) precisely defining the "binding sequence," (c) acquiring information on the binding site in the partner protein, (d) investigating the effect of conformational changes in proteins on binding to peptides, (e) determining the effect of physicochemical modification of peptides on binding of proteins, and (f) identifying epitopes recognized by anti-oxidase component antibodies by binding of antibody to peptide arrays derived from the component.
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Affiliation(s)
- Edgar Pick
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
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Schröder K, Weissmann N, Brandes RP. Organizers and activators: Cytosolic Nox proteins impacting on vascular function. Free Radic Biol Med 2017; 109:22-32. [PMID: 28336130 DOI: 10.1016/j.freeradbiomed.2017.03.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 02/24/2017] [Accepted: 03/14/2017] [Indexed: 01/25/2023]
Abstract
NADPH oxidases of the Nox family are important enzymatic sources of reactive oxygen species (ROS) in the cardiovascular system. Of the 7 members of the Nox family, at least three depend for their activation on specific cytosolic proteins. These are p47phox and its homologue NoxO1 and p67phox and its homologue NoxA1. Also the Rho-GTPase Rac is important but as this protein has many additional functions, it will not be covered here. The Nox1 enzyme is preferentially activated by the combination of NoxO1 with NoxA1, whereas Nox2 gains highest activity with p47phox together with p67phox. As p47phox, different to NoxO1 contains an auto inhibitory region it has to be phosphorylated prior to complex formation. In the cardio-vascular system, all cytosolic Nox proteins are expressed but the evidence for their contribution to ROS production is not well established. Most data have been collected for p47phox, whereas NoxA1 has basically not yet been studied. In this article the specific aspects of cytosolic Nox proteins in the cardiovascular system with respect to Nox activation, their expression and their importance will be reviewed. Finally, it will be discussed whether cytosolic Nox proteins are suitable pharmacological targets to tamper with vascular ROS production.
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Affiliation(s)
- Katrin Schröder
- Institut für Kardiovaskuläre Physiologie, Goethe-Universität Frankfurt, Frankfurt, Germany.
| | - Norbert Weissmann
- Excellence Cluster Cardiopulmonary System, University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Justus-Liebig-University, 35392 Giessen, Germany
| | - Ralf P Brandes
- Institut für Kardiovaskuläre Physiologie, Goethe-Universität Frankfurt, Frankfurt, Germany
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Xu S, Zhao Y, Jin C, Yu L, Ding F, Fu G, Zhu J. PKC/NADPH oxidase are involved in the protective effect of pioglitazone in high homocysteine-induced paracrine dyfunction in endothelial progenitor cells. Am J Transl Res 2017; 9:1037-1048. [PMID: 28386331 PMCID: PMC5375996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/06/2017] [Indexed: 06/07/2023]
Abstract
Increasing evidence suggests that EPCs improve neovascularization and endothelial regeneration via the production of paracrine factors. VEGF and IL-8 are major cytokines involved in EPC-mediated angiogenesis and re-endothelialization. In our previous studies, Hcy impaired EPC migratory and adhesive activities. We devised this study to determine whether Hcy could affect the expression and secretion of VEGF and IL-8 from EPCs. We found that high levels of Hcy (100-500 μM) decreased the EPC-mediated protein secretion and mRNA expression of VEGF and IL-8. Moreover, PIO, a PPARγ agonist, has been suggested to regulate EPC adhesion, migration, survival. In this study, PIO normalized the production of these cytokines by EPCs stimulated with Hcy. These effects of Hcy and PIO were primarily mediated by PKC and ROS via NADPH oxidase. We further confirmed this mechanism via knockdown of the NADPH oxidase subunits p67phox and Nox2. Furthermore, the PPARγ inhibitor GW9662 was not observed to abrogate the beneficial effect of PIO, indicating that PIO protected EPC paracrine function against Hcy in a PPARγ-independent manner.
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Affiliation(s)
- Shengjie Xu
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
| | - Yanbo Zhao
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
| | - Chongying Jin
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
| | - Lu Yu
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
| | - Fang Ding
- The Province Center for Cardio-Cerebral-Vascular Disease, Zhejiang Hospital Hangzhou, Zhejiang, China
| | - Guosheng Fu
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
| | - Junhui Zhu
- Department of Cardiology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University Hangzhou 310016, China
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Zheleznova NN, Yang C, Cowley AW. Role of Nox4 and p67phox subunit of Nox2 in ROS production in response to increased tubular flow in the mTAL of Dahl salt-sensitive rats. Am J Physiol Renal Physiol 2016; 311:F450-8. [PMID: 27279484 DOI: 10.1152/ajprenal.00187.2016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Accepted: 06/03/2016] [Indexed: 11/22/2022] Open
Abstract
Nox4 and Nox2 are the most abundant NADPH oxidases (Nox) in the kidney and have been shown to contribute to hypertension, renal oxidative stress, and injury in Dahl salt-sensitive (SS) hypertensive rats. The present study focused on the role of Nox4 and p67phox/Nox2 in the generation of H2O2 and O2 (·-) in the renal medullary thick ascending limb of Henle (mTAL) of SS rats in response to increasing luminal flow (from 5 to 20 nl/min). Nox4 and p67phox/Nox2 genes were found to be expressed in the mTAL of SS rats. Responses of SS rats were compared with those of SS rats with knockout of Nox4 (SS(Nox4-/-)) or functional mutation of p67phox (SS(p67phox-/-)). Nox4 was the dominant source of increased intracellular H2O2 production in response to increased luminal flow as determined using the fluorescent dye peroxyfluor 6-AM (PF6-AM). The rate of mitochondrial H2O2 production [as determined by mitochondria peroxy yellow 1 (mitoPY1)] was also significantly reduced in SS(Nox4-/-) compared with SS rats, but not in SS(p67phox-/-) rats. In contrast, intracellular superoxide (O2 (·-)) production (the ratio of ethidium to dihydroethidium) in the mTAL of SS(Nox4-/-) rats was nearly identical to that of SS rats in response to luminal flow, indicating that Nox4 made no measurable contribution. mTAL O2 (·-) production was reduced in SS(p67phox-/-) compared with SS rats at the lower luminal flow of 5 nl/min and progressively increased when perfusion was changed to 20 nl/min. We conclude that increased mTAL luminal flow results in increases in intracellular and mitochondrial H2O2, which are dependent on the presence of Nox4, and that p67phox/Nox2 accounts solely for increases in O2 (·-) production.
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Affiliation(s)
| | - Chun Yang
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Allen W Cowley
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
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Salehpour F, Ghanian Z, Yang C, Zheleznova NN, Kurth T, Dash RK, Cowley AW, Ranji M. Effects of p67phox on the mitochondrial oxidative state in the kidney of Dahl salt-sensitive rats: optical fluorescence 3-D cryoimaging. Am J Physiol Renal Physiol 2015; 309:F377-82. [PMID: 26062875 DOI: 10.1152/ajprenal.00098.2015] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/09/2015] [Indexed: 02/07/2023] Open
Abstract
The goal of the present study was to quantify and correlate the contribution of the cytosolic p67(phox) subunit of NADPH oxidase 2 to mitochondrial oxidative stress in the kidneys of the Dahl salt-sensitive (SS) hypertensive rat. Whole kidney redox states were uniquely assessed using a custom-designed optical fluorescence three-dimensional cryoimager to acquire multichannel signals of the intrinsic fluorophores NADH and FAD. SS rats were compared with SS rats in which the cytosolic subunit p67(phox) was rendered functionally inactive by zinc finger nuclease mutation of the gene (SS(p67phox)-null rats). Kidneys of SS rats fed a 0.4% NaCl diet exhibited significantly (P = 0.023) lower tissue redox ratio (NADH/FAD; 1.42 ± 0.06, n = 5) than SS(p67phox)-null rats (1.64 ± 0.07, n = 5), indicating reduced levels of mitochondrial electron transport chain metabolic activity and enhanced oxidative stress in SS rats. When fed a 4.0% salt diet for 21 days, both strains exhibited significantly lower tissue redox ratios (P < 0.001; SS rats: 1.03 ± 0.05, n = 9, vs. SS(p67phox)-null rats: 1.46 ± 0.04, n = 7) than when fed a 0.4% salt, but the ratio was still significantly higher in SS(p67phox) rats at the same salt level as SS rats. These results are consistent with results from previous studies that found elevated medullary interstitial fluid concentrations of superoxide and H2O2 in the medulla of SS rats. We conclude that the p67(phox) subunit of NADPH oxidase 2 plays an important role in the excess production of ROS from mitochondria in the renal medulla of the SS rat.
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Affiliation(s)
- F Salehpour
- Biophotonics Lab, University of Wisconsin, Milwaukee, Wisconsin; and
| | - Z Ghanian
- Biophotonics Lab, University of Wisconsin, Milwaukee, Wisconsin; and
| | - C Yang
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - N N Zheleznova
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - T Kurth
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - R K Dash
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - A W Cowley
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - M Ranji
- Biophotonics Lab, University of Wisconsin, Milwaukee, Wisconsin; and
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Bechor E, Dahan I, Fradin T, Berdichevsky Y, Zahavi A, Federman Gross A, Rafalowski M, Pick E. The dehydrogenase region of the NADPH oxidase component Nox2 acts as a protein disulfide isomerase (PDI) resembling PDIA3 with a role in the binding of the activator protein p67 (phox.). Front Chem 2015; 3:3. [PMID: 25699251 PMCID: PMC4316792 DOI: 10.3389/fchem.2015.00003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Accepted: 01/09/2015] [Indexed: 11/28/2022] Open
Abstract
The superoxide (O(·-) 2)-generating NADPH oxidase of phagocytes consists of a membrane component, cytochrome b 558 (a heterodimer of Nox2 and p22 (phox) ), and four cytosolic components, p47 (phox) , p67 (phox) , p40 (phox) , and Rac. The catalytic component, responsible for O(·-) 2 generation, is Nox2. It is activated by the interaction of the dehydrogenase region (DHR) of Nox2 with the cytosolic components, principally with p67 (phox) . Using a peptide-protein binding assay, we found that Nox2 peptides containing a (369)CysGlyCys(371) triad (CGC) bound p67 (phox) with high affinity, dependent upon the establishment of a disulfide bond between the two cysteines. Serially truncated recombinant Nox2 DHR proteins bound p67 (phox) only when they comprised the CGC triad. CGC resembles the catalytic motif (CGHC) of protein disulfide isomerases (PDIs). This led to the hypothesis that Nox2 establishes disulfide bonds with p67 (phox) via a thiol-dilsulfide exchange reaction and, thus, functions as a PDI. Evidence for this was provided by the following: (1) Recombinant Nox2 protein, which contained the CGC triad, exhibited PDI-like disulfide reductase activity; (2) Truncation of Nox2 C-terminal to the CGC triad or mutating C369 and C371 to R, resulted in loss of PDI activity; (3) Comparison of the sequence of the DHR of Nox2 with PDI family members revealed three small regions of homology with PDIA3; (4) Two monoclonal anti-Nox2 antibodies, with epitopes corresponding to regions of Nox2/PDIA3 homology, reacted with PDIA3 but not with PDIA1; (5) A polyclonal anti-PDIA3 (but not an anti-PDIA1) antibody reacted with Nox2; (6) p67 (phox) , in which all cysteines were mutated to serines, lost its ability to bind to a Nox2 peptide containing the CGC triad and had an impaired capacity to support oxidase activity in vitro. We propose a model of oxidase assembly in which binding of p67 (phox) to Nox2 via disulfide bonds, by virtue of the intrinsic PDI activity of Nox2, stabilizes the primary interaction between the two components.
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Affiliation(s)
| | | | | | | | | | | | | | - Edgar Pick
- The Julius Friedrich Cohnheim Laboratory of Phagocyte Research, Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv UniversityTel Aviv, Israel
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Matono R, Miyano K, Kiyohara T, Sumimoto H. Arachidonic acid induces direct interaction of the p67(phox)-Rac complex with the phagocyte oxidase Nox2, leading to superoxide production. J Biol Chem 2014; 289:24874-84. [PMID: 25056956 DOI: 10.1074/jbc.m114.581785] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The phagocyte NADPH oxidase Nox2, heterodimerized with p22(phox) in the membrane, is dormant in resting cells but becomes activated upon cell stimulation to produce superoxide, a precursor of microbicidal oxidants. Nox2 activation requires two switches to be turned on simultaneously: a conformational change of the cytosolic protein p47(phox) and GDP/GTP exchange on the small GTPase Rac. These proteins, in an active form, bind to their respective targets, p22(phox) and p67(phox), leading to productive oxidase assembly at the membrane. Although arachidonic acid (AA) efficiently activates Nox2 both in vivo and in vitro, the mechanism has not been fully understood, except that AA induces p47(phox) conformational change. Here we show that AA elicits GDP-to-GTP exchange on Rac at the cellular level, consistent with its role as a potent Nox2 activator. However, even when constitutively active forms of p47(phox) and Rac1 are both expressed in HeLa cells, superoxide production by Nox2 is scarcely induced in the absence of AA. These active proteins also fail to effectively activate Nox2 in a cell-free reconstituted system without AA. Without affecting Rac-GTP binding to p67(phox), AA induces the direct interaction of Rac-GTP-bound p67(phox) with the C-terminal cytosolic region of Nox2. p67(phox)-Rac-Nox2 assembly and superoxide production are both abrogated by alanine substitution for Tyr-198, Leu-199, and Val-204 in the p67(phox) activation domain that localizes the C-terminal to the Rac-binding domain. Thus the "third" switch (AA-inducible interaction of p67(phox)·Rac-GTP with Nox2) is required to be turned on at the same time for Nox2 activation.
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Affiliation(s)
- Rumi Matono
- From the Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Kei Miyano
- From the Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Takuya Kiyohara
- From the Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Hideki Sumimoto
- From the Department of Biochemistry, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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17
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Roos D, van Buul JD, Tool ATJ, Matute JD, Marchal CM, Hayee B, Köker MY, de Boer M, van Leeuwen K, Segal AW, Pick E, Dinauer MC. Two CGD Families with a Hypomorphic Mutation in the Activation Domain of p67 phox. J Clin Cell Immunol 2014; 5:1000231. [PMID: 25937994 PMCID: PMC4414043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
STUDY BACKGROUND Chronic granulomatous Disease (CGD) is a rare immunodeficiency caused by a defect in the leukocyte NADPH oxidase. This enzyme generates superoxide, which is needed for the killing of bacteria and fungi by phagocytic leukocytes. Most CGD patients have mutations in CYBB, the X-linked gene that encodes gp91phox, the catalytic subunit of the leukocyte NADPH oxidase. We report here three autosomal recessive CGD patients from two families with a homozygous mutation in NCF2, the gene that encodes p67phox, the activator subunit of the NADPH oxidase. METHODS Leukocyte NADPH oxidase activity, expression of oxidase components and gene sequences were measured with standard methods. The mutation found in the patients' NCF2 gene was expressed as Ala202Val-p67phox in K562 cells to measure its effect on NADPH oxidase activity. Translocation of the mutated p67phox from the cytosol of the patients' neutrophils to the plasma membrane was measured by confocal microscopy and by Western blotting after membrane purification. RESULTS The exceptional feature of the A67 CGD patients reported here is that the p.Ala202Val mutation in the activation domain of p67phox was clearly hypomorphic: substantial expression of p67phox protein was noted and the NADPH oxidase activity in the neutrophils of the patients was 20-70% of normal, dependent on the stimulus used to activate the cells. The extent of Ala202Val-p67phox translocation to the plasma membrane during cell activation was also stimulus dependent. Ala202Val-p67phox in K562 cells mediated only about 3% of normal oxidase activity compared to cells transfected with the wild-type p67phox. CONCLUSION The mutation found in NCF2 is the cause of the decreased NADPH oxidase activity and the (mild) clinical problems of the patients. We propose that the p.Ala202Val mutation has changed the conformation of the activation domain of p67phox, resulting in reduced activation of gp91phox.
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Affiliation(s)
- Dirk Roos
- Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Jaap D van Buul
- Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Anton TJ Tool
- Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Juan D Matute
- Departments of Pediatrics (Hematology/Oncology), Microbiology/Immunology, and Medical and Molecular Genetics, Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Christophe M Marchal
- Departments of Pediatrics (Hematology/Oncology), Microbiology/Immunology, and Medical and Molecular Genetics, Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Bu’Hussain Hayee
- Department of Medicine, University College London, London, United Kingdom
| | - M Yavuz Köker
- Department of Immunology and Immunology Laboratory, Faculty of Medicine, University of Erciyes, Kayseri, Turkey
| | - Martin de Boer
- Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Karin van Leeuwen
- Sanquin Research and Landsteiner Laboratory, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
| | - Anthony W Segal
- Department of Medicine, University College London, London, United Kingdom
| | - Edgar Pick
- Julius Friedrich Cohnheim Laboratory of Phagocyte Research, Sackler School of Medicine, Tel Aviv University, Israel
| | - Mary C Dinauer
- Departments of Pediatrics (Hematology/Oncology), Microbiology/Immunology, and Medical and Molecular Genetics, Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, IN, USA
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Pick E. Role of the Rho GTPase Rac in the activation of the phagocyte NADPH oxidase: outsourcing a key task. Small GTPases 2014; 5:e27952. [PMID: 24598074 PMCID: PMC4114928 DOI: 10.4161/sgtp.27952] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 01/10/2014] [Accepted: 01/22/2014] [Indexed: 11/19/2022] Open
Abstract
The superoxide-generating NADPH oxidase of phagocytes consists of the membrane-associated cytochrome b 558 (a heterodimer of Nox2 and p22(phox)) and 4 cytosolic components: p47(phox), p67(phox), p40(phox), and the small GTPase, Rac, in complex with RhoGDI. Superoxide is produced by the NADPH-driven reduction of molecular oxygen, via a redox gradient located in Nox2. Electron flow in Nox2 is initiated by interaction with cytosolic components, which translocate to the membrane, p67(phox) playing the central role. The participation of Rac is expressed in the following sequence: (1) Translocation of the RacGDP-RhoGDI complex to the membrane; (2) Dissociation of RacGDP from RhoGDI; (3) GDP to GTP exchange on Rac, mediated by a guanine nucleotide exchange factor; (4) Binding of RacGTP to p67(phox); (5) Induction of a conformational change in p67(phox), promoting interaction with Nox2. The particular involvement of Rac in NADPH oxidase assembly serves as a paradigm for signaling by Rho GTPases, in general.
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Affiliation(s)
- Edgar Pick
- Julius Friedrich Cohnheim Laboratory of Phagocyte Research; Department of Clinical Microbiology and Immunology; Sackler School of Medicine; Tel Aviv University; Tel Aviv, Israel
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Nunes P, Demaurex N, Dinauer MC. Regulation of the NADPH oxidase and associated ion fluxes during phagocytosis. Traffic 2013; 14:1118-31. [PMID: 23980663 DOI: 10.1111/tra.12115] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 08/19/2013] [Accepted: 08/23/2013] [Indexed: 12/01/2022]
Abstract
The production of reactive oxygen species (ROS) within immune cell phagosomes is critical for antimicrobial activity and for correct antigen processing, and influences signaling pathways that direct host responses to infection and inflammation. Because excess oxidants can cause tissue damage and oxidative stress, phagocytes must precisely control both the location and timing of NADPH oxidase activity. How differential regulation is achieved at phagosomes is not well understood. Recent studies have revealed that the PI(3)P phosphoinositide plays an important role in locally boosting phagosomal NADPH oxidase activity through its binding to the p40(phox) NADPH oxidase subunit. Furthermore, phox subunit dynamics at phagosomes may regulate the timing of the oxidative burst. Novel elements regulating catalytic core trafficking include Rab27 and SNAP-23. In addition to trafficking events, the activity of the electrogenic oxidase is also governed by ionic fluxes, which are constrained at phagosomes owing to low intraphagosomal volume and dynamic display of channels, transporters, and pumps. New insights on the interdependence of phagosomal pH and ROS have been recently elucidated, and chloride channels important for microbicidal functions, including CFTR, and CLIC family channels, have been identified. Finally, periphagosomal calcium microdomains and calcium-dependent S100A8/9 protein recruitment may help fine-tune spatiotemporal regulation of NADPH oxidase activation for an effective immune response.
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Affiliation(s)
- Paula Nunes
- Department of Cell Physiology and Metabolism, University of Geneva, 1 rue Michel-Servet, CH-1211, Geneva 4, Switzerland
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