Hv1 is the only voltage-gated proton-selective channel in mammalian cells. It contains a conserved voltage-sensor domain, shared by a large class of voltage-gated ion channels, but lacks a pore domain. Its primary role is to extrude protons from the cytoplasm upon pH reduction and membrane depolarization. The best-known function of Hv1 is the regulation of cytosolic pH and the nicotinamide adenine dinucleotide phosphate oxidase-dependent production of reactive oxygen species. Accumulating evidence indicates that Hv1 is expressed in nervous systems, in addition to immune cells and others. Here, we summarize the molecular properties, distribution, and physiological functions of Hv1 in the peripheral and central nervous systems. We describe the recently discovered functions of Hv1 in various neurological diseases, including brain or spinal cord injury, ischemic stroke, demyelinating diseases, and pain. We also summarize the current advances in the discovery and application of Hv1-targeted small molecules in neurological diseases. Finally, we discuss the current limitations of our understanding of Hv1 and suggest future research directions.
Animals ; Protons ; Ion Channels/metabolism* ; Reactive Oxygen Species/metabolism* ; Brain/metabolism* ; NADPH Oxidases ; Mammals/metabolism*

OBJECTIVE: To explore the correlation of cytochrome B-245 alpha chain (CYBA) rs4673 and cholesteryl ester transfer protein (CETP) rs12720922 polymorphisms with the susceptibility of gene-ralized aggressive periodontitis (GAgP). METHODS: The study was a case-control trial. A total of 372 GAgP patients and 133 periodontally healthy controls were recruited. The CYBA rs4673 and CETP rs12720922 polymorphisms were detected by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). Logistic regression models were used to analyze the correlation of CYBA rs4673 and CETP rs12720922 variants with the susceptibility of GAgP. The interaction between the two gene polymorphisms to the susceptibility of GAgP was analyzed by the likelihood ratio test. The interaction model adopted was the multiplication model. RESULTS: The mean age of GAgP group and control group was (27.5±5.2) years and (28.8±7.1) years respectively. There was significant difference in age between the two groups (P < 0.05). The gender distribution (male/female) was 152/220 and 53/80 respectively, and there was no significant difference between GAgP group and controls (P>0.05). For CYBA rs4673, the frequency of CT/TT genotype in the GAgP group was significantly higher than that in the controls [18.0% (66/366) vs. 10.6% (14/132), P < 0.05]. After adjusting age and gender, the individuals with CT/TT genotype had a higher risk of GAgP (OR=1.86, 95%CI: 1.01-3.45, P < 0.05), compared with CC genotype. There was no statistically significant difference in distributions of the CETP rs12720922 genotypes (GG, AA/AG) between GAgP patients and healthy controls (P>0.05). A significant interaction between CYBA rs4673 and CETP rs12720922 in the susceptibility to GAgP was observed. The GAgP risk of the individuals with CYBA rs4673 CT/TT and CETP rs12720922 GG genotypes was significantly increased (OR=3.25, 95%CI: 1.36-7.75, P < 0.01), compared with those carrying CC and AA/AG genotypes. CONCLUSION CYBA rs4673 CT/TT genotype is associated with GAgP susceptibility. There is a significant interaction between CYBA rs4673 CT/TT genotype and CETP rs12720922 GG genotype in the susceptibility of GAgP.
Adult ; Aggressive Periodontitis/genetics* ; Case-Control Studies ; Cholesterol Ester Transfer Proteins/genetics* ; Cytochrome b Group ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; NADPH Oxidases/genetics* ; Polymorphism, Single Nucleotide ; Young Adult

Nicotinamide adenine dinucleotide phosphate oxidase (NOX) is a major source of reactive oxygen species (ROS) in the cardiovascular system. The family of NOX includes seven isoforms, and expressed in different cardiovascular cell types and cell compartments, modulating multiple functions, such as cell proliferation, migration, differentiation, apoptosis, senescence, and inflammatory responses. The NOX-derived ROS are involved in many processes associated with cardiovascular diseases, such as hypertension, atherosclerosis, diabetic vascular disease, ventricular remodeling after myocardial infarction, and so on.
Cardiovascular Diseases ; Humans ; Hypertension ; NADPH Oxidases ; Oxidation-Reduction ; Oxidative Stress ; Reactive Oxygen Species

Production of reactive oxygen species (ROS) is a conserved immune response primarily mediated by NADPH oxidases (NOXs), also known in plants as respiratory burst oxidase homologs (RBOHs). Most microbe-associated molecular patterns (MAMPs) trigger a very fast and transient ROS burst in plants. However, recently, we found that lipopolysaccharides (LPS), a typical bacterial MAMP, triggered a biphasic ROS burst. In this study, we isolated mutants defective in LPS-triggered biphasic ROS burst (delt) in Arabidopsis, and cloned the DELT1 gene that was shown to encode RBOHD. In the delt1-2 allele, the antepenultimate residue, glutamic acid (E919), at the C-terminus of RBOHD was mutated to lysine (K). E919 is a highly conserved residue in NADPH oxidases, and a mutation of the corresponding residue E568 in human NOX2 has been reported to be one of the causes of chronic granulomatous disease. Consistently, we found that residue E919 was indispensable for RBOHD function in the MAMP-induced ROS burst and stomatal closure. It has been suggested that the mutation of this residue in other NADPH oxidases impairs the protein's stability and complex assembly. However, we found that the E919K mutation did not affect RBOHD protein abundance or the ability of protein association, suggesting that the residue E919 in RBOHD might have a regulatory mechanism different from that of other NOXs. Taken together, our results confirm that the antepenultimate residue E is critical for NADPH oxidases and provide a new insight into the regulatory mechanisms of RBOHD.
Agrobacterium tumefaciens/metabolism* ; Alleles ; Arabidopsis/metabolism* ; Arabidopsis Proteins/genetics* ; Gene Expression Regulation, Plant ; Genetic Techniques ; Humans ; Lipopolysaccharides/metabolism* ; Luminescence ; Mutation ; NADPH Oxidase 2/chemistry* ; NADPH Oxidases/genetics* ; Plant Stomata/metabolism* ; Protein Domains ; Reactive Oxygen Species/metabolism* ; Nicotiana/metabolism*

The increased levels of intracellular reactive oxygen species (ROS) in granulosa cells (GCs) may affect the pregnancy results in women with polycystic ovary syndrome (PCOS). In this study, we compared the in vitro fertilization and embryo transfer (IVF-ET) results of 22 patients with PCOS and 25 patients with tubal factor infertility and detected the ROS levels in the GCs of these two groups. Results showed that the PCOS group had significantly larger follicles on the administration day for human chorionic gonadotropin than the tubal factor group (P < 0.05); however, the number of retrieved oocytes was not significantly different between the two groups (P > 0.05). PCOS group had slightly lower fertilization, cleavage, grade I/II embryo, clinical pregnancy, and implantation rates and higher miscarriage rate than the tubal factor group (P > 0.05). We further found a significantly higher ROS level of GCs in the PCOS group than in the tubal factor group (P < 0.05). The increased ROS levels in GCs caused GC apoptosis, whereas NADPH oxidase 2 (NOX2) specific inhibitors (diphenyleneiodonium and apocynin) significantly reduced the ROS production in the PCOS group. In conclusion, the increased ROS expression levels in PCOS GCs greatly induced cell apoptosis, which further affected the oocyte quality and reduced the positive IVF-ET pregnancy results of women with PCOS. NADPH oxidase pathway may be involved in the mechanism of ROS production in GCs of women with PCOS.
Abortion, Spontaneous ; epidemiology ; Acetophenones ; therapeutic use ; Adult ; Apoptosis ; drug effects ; Embryo Transfer ; Female ; Fertilization in Vitro ; Granulosa Cells ; metabolism ; Humans ; NADPH Oxidases ; antagonists & inhibitors ; Onium Compounds ; therapeutic use ; Oocyte Retrieval ; Oxidative Stress ; Polycystic Ovary Syndrome ; drug therapy ; Pregnancy ; Pregnancy Rate ; Reactive Oxygen Species ; metabolism

The aims of the present study were to evaluate the effects of puerarin on angiotensin II-induced cardiac fibroblast proliferation and to explore the molecular mechanisms of action. Considering the role of HO in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation, we hypothesized that modulating catalase activity would be a potential target in regulating the redox-sensitive pathways. Our results showed that the activation of Rac1 was dependent on the levels of intracellular HO. Puerarin blocked the phosphorylation of extracellular regulated protein kinases (ERK)1/2, abolished activator protein (AP)-1 binding activity, and eventually attenuated cardiac fibroblast proliferation through the inhibition of HO-dependent Rac1 activation. Further studies revealed that angiotensin II treatment resulted in decreased catalase protein expression and enzyme activity, which was disrupted by puerarin via the upregulation of catalase protein expression at the transcriptional level and the prolonged protein degradation. These findings indicated that the anti-proliferation mechanism of puerarin was mainly through blocking angiontensin II-triggered downregulation of catalase expression and HO-dependent Rac1 activation.
Angiotensin II ; pharmacology ; Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Animals ; Animals, Newborn ; Catalase ; genetics ; metabolism ; Cell Proliferation ; drug effects ; Cells, Cultured ; Extracellular Signal-Regulated MAP Kinases ; antagonists & inhibitors ; metabolism ; Fibroblasts ; Gene Expression Regulation ; drug effects ; Heart ; drug effects ; Hydrogen Peroxide ; metabolism ; pharmacology ; Isoflavones ; pharmacology ; Mice ; Myocardium ; cytology ; enzymology ; metabolism ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Neuropeptides ; metabolism ; Signal Transduction ; drug effects ; Transcription Factor AP-1 ; antagonists & inhibitors ; metabolism ; Transcriptional Activation ; drug effects ; rac1 GTP-Binding Protein ; metabolism

OBJECTIVETo investigate the effect of angiotension II (AngII) on the activation of NLRP3 inflammasome and the expression of interleukin-1β (IL-1β) in human umbilical vein endothelial cells (HUVECs).

METHODSHUVECs cultured in vitro were treated with different concentrations of AngII for varying lengths of time to determine the optimal concentration and time for AngII exposure. To test the impact of different agents on the effect of AngII exposure, HUVECs were pretreated with AngII receptor blocker losartan, NAD(P)H inhibitor DPI and H(2)O(2) scavenger CAT, caspase 1 inhibitor YVAD, or NLRP3 siRNA for silencing NLRP3, and the protein levels of NOX4, NLRP3, caspase-1 and IL-1β in HUVECs were analyzed by Western blotting.

RESULTSAngII treatment at the optimal concentration (10(-9) mol/L) for 12 h significantly increased the protein levels of NOX4, NLRP3, caspase1 and IL-1β in HUVECs. Pretreatment with losartan, DPI, CAT, YVAD, or NLRP3 siRNA all attenuated the effects of AngII on the cells.

CONCLUSIONAngII can induce vascular inflammation by promoting the production of reactive oxygen species and activating NLRP3 inflammasome to increase the protein expression of IL-1β in HUVECs.

Adaptor Proteins, Signal Transducing ; pharmacology ; Angiotensin II ; pharmacology ; Blotting, Western ; Carrier Proteins ; metabolism ; Caspase 1 ; metabolism ; Human Umbilical Vein Endothelial Cells ; metabolism ; Humans ; Hydrogen Peroxide ; Inflammasomes ; metabolism ; Interleukin-1beta ; metabolism ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; NLR Family, Pyrin Domain-Containing 3 Protein ; RNA, Small Interfering ; Reactive Oxygen Species ; metabolism

The purpose of the present study is to explore the effect of aliskiren on the proliferation of cardiac fibroblasts (CFs) in AGT-REN double transgenic hypertensive (dTH) mice. The cultured CFs from AGT-REN dTH mice were divided into AGT-REN group (dTH) and aliskiren group (ALIS). Cultured CFs from C57B6 mice were served as control (WT). The effect of different concentration of aliskiren (1 × 10, 1 × 10, 1 × 10, 1 × 10mol/L) on CFs proliferation was determined by MTT assay. After treatment with 1 × 10mol/L aliskiren for 24 h, α-SMA, collagen I, III and NADPH oxidase (NOX) protein expression in CFs of AGT-REN dTH mice were detected by Western blot. The collagen synthesis in CFs was assessed by hydroxyproline kit. The expression of ROS was determined by DHE. Results showed that the blood pressure and plasma Ang II levels were significantly increased and CFs proliferation was significantly increased as well in AGT-REN dTH mice compared with WT group. However, aliskiren intervention decreased CFs proliferation, myofibroblast transformation, as well as the collagen I and III synthesis in CFs of AGT-REN dTH mice. Meanwhile, aliskiren inhibited ROS content and NOX2/NOX4 protein expression in CFs of AGT-REN dTH mice. These results suggest that aliskiren decreases the cell proliferation, myofibroblast transformation and collagen production in CFs of AGT-REN dTH mice, which might be through inhibition of oxidative stress response.
Amides ; Animals ; Blood Pressure ; Cell Proliferation ; Cells, Cultured ; Collagen ; Collagen Type I ; Fumarates ; Heart ; Hydroxyproline ; Hypertension ; Mice ; Mice, Transgenic ; Myocardium ; Myofibroblasts ; NADPH Oxidases

Endoplasmic reticulum (ER) stress is involved in the process of kidney fibrosis. Spliced X-box binding protein 1 (XBP1S) is the key mediator of ER stress while its role in fibrosis is still poorly understood. This study was aimed to investigate the role of XBP1S in renal fibrosis and evaluate whether valsartan could alleviate fibrosis through XBP1S. Renal interstitial fibrosis was induced by unilateral ureteral obstruction (UUO) in C57BL/6 mice, and UUO mice were daily administered with valsartan (20 mg/kg) through oral gavage. After 7 days of UUO, at euthanasia, left kidney was collected to examine the histological alteration by using haematoxylin-eosin staining, Masson's trichrome staining, Sirius red staining and immunohistochemistry. Western blot was used to assess XBP1S, targets of XBP1S, fibronectin, α-SMA, BAX and BCL2 protein levels. Real-time polymerase chain reaction was performed to assess NADPH oxidase subunits p47-phox and p67-phox mRNA levels. The results showed that XBP1S expression was decreased by about 70% in the UUO mice compared with that in sham mice (P < 0.01), which was reversed by valsartan administration (P < 0.05). Meanwhile, UUO-induced renal interstitial fibrosis was attenuated by valsartan treatment. In addition, the protein levels of fibronectin and α-SMA were upregulated by UUO induction (P < 0.01), and valsartan administration inhibited the protein levels of fibronectin and α-SMA in UUO mice (P < 0.05). Western blot analysis showed that the ratio of BAX to BCL2 protein level was increased in UUO model compared with that in sham mice, and the increment also was diminished by valsartan treatment (P < 0.05). Finally, UUO-induced mRNA levels of p47-phox and p67-phox were significantly attenuated by valsartan administration (P < 0.05). These results showed that valsartan at least partly restores renal interstitial fibrosis by enhancing XBP1S activation through inhibiting oxidative stress and apoptosis in the UUO mice. These results suggest that XBP1S could be a potential therapeutic target for kidney fibrosis.
Animals ; Apoptosis ; Fibronectins ; Fibrosis ; Kidney ; Kidney Diseases ; Mice ; Mice, Inbred C57BL ; NADPH Oxidases ; Oxidative Stress ; Phosphoproteins ; Real-Time Polymerase Chain Reaction ; Ureteral Obstruction ; X-Box Binding Protein 1

OBJECTIVETo investigate the effect and the potential mechanism of Senegenin (Sen) against injury induced by hypoxia/reoxygenation (H/R) in highly differentiated PC12 cells.

METHODSThe cultured PC12 cells were treated with H/R in the presence or absence of Sen (60 μmol/L). Four groups were included in the experiment: control group, H/R group, H/R+Sen group and Sen group. Cell viability of each group and the level of lactate dehydrogenase (LDH) in culture medium were detected for the pharmacological effect of Sen. Hoechst 33258 staining and annexin V/propidium iodide double staining were used to analyze the apoptosis rate. Moreover, mitochondrial membrane potential (△Ψm), reactive oxygen species (ROS) and intracellular free calcium ([Ca(2+)]i) were measured by fluorescent staining and flow cytometry. Cleaved caspase-3 and activity of NADPH oxidase (NOX) were determined by colorimetric protease assay and enzyme linked immunosorbent assay, respectively.

RESULTSSen significantly elevated cell viability (P<0.05), decreased the leakage of LDH (P<0.05) and apoptosis rate (P<0.05) in H/R-injured PC12 cells. Sen maintained the value of △Ψm (P<0.05) and suppressed the activity of caspase-3 (P<0.05). Moreover, Sen reduced ROS accumulation P<0.05) and [Ca(2+)]i increment (P<0.05) by inhibiting the activity of NOX (P<0.05).

CONCLUSIONSen may exert cytoprotection against H/R injury by decreasing the levels of intracellular ROS and [Ca(2+)]i, thereby suppressing the mitochondrial pathway of cellular apoptosis.

Animals ; Apoptosis ; drug effects ; Calcium ; metabolism ; Caspase 3 ; metabolism ; Cell Hypoxia ; drug effects ; Cell Nucleus ; drug effects ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Flow Cytometry ; Fluorescence ; Intracellular Space ; metabolism ; Membrane Potential, Mitochondrial ; drug effects ; NADPH Oxidases ; metabolism ; Neuroprotective Agents ; pharmacology ; Oxygen ; pharmacology ; PC12 Cells ; Rats ; Reactive Oxygen Species ; metabolism ; Staining and Labeling