Recent data implicate oxidative stress as a mediator of pulmonary hypertension (PH) and of the associated pathological changes to the pulmonary vasculature and right ventricle (RV). Increases in reactive oxygen specie...Recent data implicate oxidative stress as a mediator of pulmonary hypertension (PH) and of the associated pathological changes to the pulmonary vasculature and right ventricle (RV). Increases in reactive oxygen species (ROS), altered redox state, and elevated oxidant stress have been demonstrated in the lungs and RV of several animal models of PH, including chronic hypoxia, monocrotaline toxicity, caveolin-1 knock-out mouse, and the transgenic Ren2 rat which overexpresses the mouse renin gene. Generation of ROS in these models is derived mostly from the activities of the nicotinamide adenine dinucleotide phosphate oxidases, xanthine oxidase, and uncoupled endothelial nitric oxide synthase. As disease progresses circulating monocytes and bone marrow-derived monocytic progenitor cells are attracted to and accumulate in the pulmonary vasculature. Once established, these inflammatory cells generate ROS and secrete mitogenic and fibrogenic cytokines that induce cell proliferation and fibrosis in the vascular wall resulting in progressive vascular remodeling. Deficiencies in antioxidant enzymes also contribute to pulmonary hypertensive states. Current therapies were developed to improve endothelial function, reduce pulmonary artery pressure, and slow the progression of vascular remodeling in the pulmonary vasculature by targeting deficiencies in either NO (PDE-type 5 inhibition) or PGI 2 (prostacyclin analogs), or excessive synthesis of ET-1 (ET receptor blockers) with the intent to improve patient clinical status and survival. New therapies may slow disease progression to some extent, but long term management has not been achieved and mortality is still high. Although little is known concerning the effects of current pulmonary arterial hypertension treatments on RV structure and function, interest in this area is increasing. Development of therapeutic strategies that simultaneously target pathology in the pulmonary vasculature and RV may be beneficial in reducing mortality associated with RV failure.展开更多
BACKGROUND Abdominal paracentesis drainage(APD)is a safe and effective strategy for severe acute pancreatitis(SAP)patients.However,the effects of APD treatment on SAPassociated cardiac injury remain unknown.AIM To inv...BACKGROUND Abdominal paracentesis drainage(APD)is a safe and effective strategy for severe acute pancreatitis(SAP)patients.However,the effects of APD treatment on SAPassociated cardiac injury remain unknown.AIM To investigate the protective effects of APD on SAP-associated cardiac injury and the underlying mechanisms.METHODS SAP was induced by 5%sodium taurocholate retrograde injection in Sprague-Dawley rats.APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after SAP induction.Morphological staining,serum amylase and inflammatory mediators,serum and ascites high mobility group box(HMGB)1,cardiac-related enzymes indexes and cardiac function,oxidative stress markers and apoptosis and associated proteins were assessed in the myocardium in SAP rats.Nicotinamide adenine dinucleotide phosphate oxidase activity and mRNA and protein expression were also examined.RESULTS APD treatment improved cardiac morphological changes,inhibited cardiac dysfunction,decreased cardiac enzymes and reduced cardiomyocyte apoptosis,proapoptotic Bax and cleaved caspase-3 protein levels.APD significantly decreased serum levels of HMGB1,inhibited nicotinamide adenine dinucleotide phosphate oxidase expression and ultimately alleviated cardiac oxidative injury.Furthermore,the activation of cardiac nicotinamide adenine dinucleotide phosphate oxidase by pancreatitis-associated ascitic fluid intraperitoneal injection was effectively inhibited by adding anti-HMGB1 neutralizing antibody in rats with mild acute pancreatitis.CONCLUSION APD treatment could exert cardioprotective effects on SAP-associated cardiac injury through suppressing HMGB1-mediated oxidative stress,which may be a novel mechanism behind the effectiveness of APD on SAP.展开更多
Background： The calcium clearance and reactive oxygen species （ROS） generations in the coronary artery smooth muscle cells in chronic heart failure （HF） have not been fully investigated. Therefore, we attempted t...Background： The calcium clearance and reactive oxygen species （ROS） generations in the coronary artery smooth muscle cells in chronic heart failure （HF） have not been fully investigated. Therefore, we attempted to understand the gene expressions underlying the mishandling of calcium clearance and the accumulations of ROS. Methods： We initially established an animal model of chronic HF by making the left anterior descending coronary artery ligation （CAL） in rats, and then isolated the coronary artery vascular smooth muscle cells from the ischemic and the nonischemic parts of the coronary artery vessels in 12 weeks after CAL operation. The intracellular calcium concentration and ROS level were measured using flow cytometry, and the gene expressions of sarco/endoplasmic reticulum Ca2＋-ATPase （SERCA2a）, encoding sarcoplasmic reticulum Ca2＋-ATPase 2a, encoding sodium-calcium exchanger （NCX）, andp47phox encoding a subunit of the nicotinamide adenine dinucleotide phosphate （NADPH） oxidase were examined using real-time quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Results： We found that the calcium accumulation and ROS generation in the coronary artery smooth muscle cells isolated from either the ischemic or the nonischemic part of the CAL coronary artery vessel were significantly increased irrespective of blood supply （all P 〈 0.01 ）. Moreover, these were accompanied by the increased expressions of NCX and p47phox, the decreased expression of S ERCA2a, and the increased amount of phosphorylated forms of p47phox in NADPH oxidase （all P 〈 0.05）. Conclusions： Our results demonstrated that the disordered calcium clearance and the increased ROS generation occurred in the coronary artery smooth muscle cells in rats with chronic HF produced by ligation of the left anterior descending coronary artery （CAL）, and which was found to be disassociated from blood supply, and the increased generation of ROS in the ceils was found to 展开更多
Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactiv...Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactive oxygen species （ROS）, plays a critical role in the initiation and progression of fibrotic diseases. Nicotinamide adenine dinucleotide phosphate （NADPH） oxidase is the predominant enzyme source for ROS generation and is now recognized as a key mediator of cell proliferation and matrix accumulation in renal disease. Multiple stimuli and agonists, such as transforming growth factor , tumor necrosis factor, platelet derived growth factor, angiotensin II, hyperglycemia, oxidized low-density lipoprotein and albumin have been shown to alter the activity or expression of the NADPH oxidase and ultimately increase ROS production. ROS directly incites damage to biologically important macromolecules and leads to generation of the so-called advanced oxidation protein products （AOPPs） and advanced glycation end products, which are not only markers of oxidative stress but also cause renal injury. Targeting NADPH oxidase and/or reducing AOPPs production miaht be a novel strateav for the theraoeutic intervention of varietv of fibrotic kidney disorders.展开更多
Studies have demonstrated that reactive oxygen species(ROS) are closely related to inflammatory disorders. Nicotinamide adenine dinucleotide phosphate oxidase(NOX), originally found in phagocytes, is the main source o...Studies have demonstrated that reactive oxygen species(ROS) are closely related to inflammatory disorders. Nicotinamide adenine dinucleotide phosphate oxidase(NOX), originally found in phagocytes, is the main source of ROS in nonphagocytic cells. Besides directly producing the detrimental highly reactive ROS to act on biomolecules(lipids, proteins, and nucleic acids), NOX can also activate multiple signal transduction pathways, which regulate cell growth, proliferation, differentiation and apoptosis by producing ROS. Recently, research on pancreatic NOX is no longer limited to inflammatory cells, but extends to the aspect of pancreatic acinar cells and pancreatic stellate cells, which are considered to be potentially associated with pancreatitis. In this review, we summarize the literature on NOX protein structure, activation, function and its role in the pathogenesis of pancreatitis.展开更多
Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu^2＋. Treatment with 100 μmol/L Cu^2＋ generated a large amount of HzOz and thiobarbituric acid-reactive ...Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu^2＋. Treatment with 100 μmol/L Cu^2＋ generated a large amount of HzOz and thiobarbituric acid-reactive substances （TBARS） in cells. Using phospholipase D （PLD） specific inhibitor （1-butanol） or phosphatidic acid （PA）, we demonstrated that PLD plays an important role in the generation of H2O2 and TBARS. Semi-quantitative reverse-transcriptase polymerase chain reaction and enzyme activity assays with wild type and nicotinamide adenine dinucleotide phosphate （NADPH） oxidaseoverexpressing BY-2 cells revealed that PLD and PA are the key factors leading to NADPH oxidase activation, which is responsible for H2O2 and TBARS production induced by Cu^2＋. Moreover, the content of ascorbic acid （AsA）, an effective antioxidant, was sharply reduced in BY-2 cells exposed to excessive Cu^2＋. Furthermore, a significant downregulation of the enzymes of AsA biosynthesis and the antioxidant system was found. This evidence suggests that excessive Cu^2＋-elevated reactive oxygen species （ROS） production is caused by upregulated PLD that elevates the activity of NADPH oxidase and its collapsed antioxidant systems that scavenges ROS.展开更多
Background Oxidative Stress and p38 mitogen-activated protein kinase （p38MAPK） play a vital role in renal fibrosis. Pioglitazone can protect kidney but the underlying mechanisms are less clear. The purpose of this s...Background Oxidative Stress and p38 mitogen-activated protein kinase （p38MAPK） play a vital role in renal fibrosis. Pioglitazone can protect kidney but the underlying mechanisms are less clear. The purpose of this study was to investigate the effect of pioglitazone on oxidative stress and whether the severity of oxidative stress was associated with the phosphorylation level of p38MAPK.展开更多
Background The p22phox is a critical component of the superoxide-generating vascular nicotinamide adenine dinucleotide phosphate （NADPH） oxidase. Several polymorphisms in p22phox gene are studied for their associati...Background The p22phox is a critical component of the superoxide-generating vascular nicotinamide adenine dinucleotide phosphate （NADPH） oxidase. Several polymorphisms in p22phox gene are studied for their association with cardiovascular diseases. However, no publication is available to assess the relation of 549C〉T polymorphism in p22pho~ gene to coronary artery disease （CAD） risk. This study was to investigate the effect of the p22phox gene 549C〉T polymorphism on CAD risk. Methods Hospital-based case-control study was conducted with 297 CAD patients and 343 healthy persons as the control group. Polymerase chain reaction and pyrosequencing using PSQ 96 MA Pyrosequencer （Biotage AB） were used to detect the polymorphisms. Multiple Logistic regression model was used to adjust the potential confounders and to estimate odds ratio （OR） with 95% confidence intervals （CIs）. Results The observed genotype frequencies of this polymorphism obeyed the Hardy-Weinberg equilibrium in both cases （P=0.439） and controls （P=-0.668）. The frequency of mutant genotypes （＇I-I-＋CT） in cases （41.08%） was higher than that in controls （36.73%） with an OR=1.20 （95% C1=0.87-1.65）. After the adjustment of the potential confounders, there was a significant association of the mutant genotypes with increased risk of CAD （OR=1.57, 95% C1=1.01-2.46, P=0.047）. Conclusions The mutant genotypes of the p22phox gene 549C〉T polymorphism had a significant effect on the increased risk of CAD in this studied population.展开更多
Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxida- tive effects and has been used to treat cardiovascular and cerebrovascular...Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxida- tive effects and has been used to treat cardiovascular and cerebrovascular diseases in China. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 （NOX2） was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 μM scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco＇s modified Eagle＇s medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 μM scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen, species in astrocytes subjected to ischemia-＇reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine （8-OHdG）, 4-hydroxy-2-nonenal （4-HNE） and 3-nitrotyr展开更多
Objective： To investigate the mechanism of Panax notoginseng saponins （PNS）, an effective component extracted from Panax notoginseng, on atherosclerotic plaque angiogenesis in atherosclerosis-prone apolipoprotein E...Objective： To investigate the mechanism of Panax notoginseng saponins （PNS）, an effective component extracted from Panax notoginseng, on atherosclerotic plaque angiogenesis in atherosclerosis-prone apolipoprotein E-knockout （ApoE-KO） mice fed with high-fat, high-cholesterol diet. Methods： Twenty ApoE-KO mice were divided into two groups, the model group and the PNS group. Ten normal C57BL/6J mice were used as a control group. PNS （60 mg/kg） was orally administered daily for 12 weeks in the PNS group, The ratio of plaque area to vessel area was examined by histological staining. The tissue sample of aortic root was used to detect the CD34 and vascular endothelial growth factor （VEGF） expression areas by immunohistochemistry. The expression of VEGF and nicotinamide adenine dinucleotide phosphate oxidase subunit 4 （NOX4） were measured by reverse transcription polymerase chain reaction and Westem blotting respectively. Results： After treatment with PNS, the plaque areas were decreased （P〈0.05）. CD34 expressing areas and VEGF expression areas in plaques were significantly decreased （P〈0.05）. Meanwhile, VEGF and NOX4 mRNA expression were decreased after treatment with PNS, VEGF and NOX4 protein expression were also decreased by about 72% and 63%, respectively （P〈0.01）. Conclusion： PNS, which decreases VEGF and NOX4 expression, could alleviate plaque angiogenesis and attenuate atherosclerosis.展开更多
Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under...Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under normal circumstances, reactive oxygen species mediate a number of important cellular functions, including the facilitation of adaptive immunity. In pathogenic circumstances, however,excess reactive oxygen species generated by NOX promotes apoptotic cell death. In ischemic stroke, in particular, it has been shown that both NOX activation and derangements in glucose metabolism result in increased apoptosis. Moreover, recent studies have established that glucose, as a NOX substrate, plays a vital role in the pathogenesis of reperfusion injury. Thus, NOX inhibition has the potential to mitigate the deleterious impact of hyperglycemia on stroke. In this paper, we provide an overview of this research,coupled with a discussion of its implications for the development of NOX inhibition as a strategy for the treatment of ischemic stroke. Both inhibition using apocynin, as well as the prospect of developing more specific inhibitors based on what is now understood of the biology of NOX assembly and activation, will be highlighted in the course of our discussion.展开更多
The activity of plasma membrane （PM） nicotinamide adenine dinucleotide phosphate （NADPH） oxidase and its catalytic properties in rice was investigated under drought stress conditions. Drought stress led to decreas...The activity of plasma membrane （PM） nicotinamide adenine dinucleotide phosphate （NADPH） oxidase and its catalytic properties in rice was investigated under drought stress conditions. Drought stress led to decreased leaf relative water content （RWC） and, as a result of drought-induced oxidative stress, the activities of antioxidant enzymes increased significantly. More interestingly, the intensity of applied water stress was correlated with increased production of H2O2 and O2^- and elevated activity of PM NADPH oxidase, a key enzyme of reactive oxygen species generation in plants. Histochemical analyses also revealed increased H2O2 and O2^- production in drought-stressed leaves. Application of diphenylene iodonium （DPI）, an inhibitor of PM NADPH oxidase, did not alleviate drought-induced production of H2O2 and O2^-. Catalysis experiments indicated that the rice PM NADPH oxidase was partially fiavin-dependent. The pH and temperature optima for this enzyme were 9.8 and 40 ℃, respectively. In addition, drought stress enhanced the activity under alkaline pH and high temperature conditions. These results suggest that a complex regulatory mechanism, associated with the NADPH oxidase-H2O2 system, is involved in the response of rice to drought stress.展开更多
文摘Recent data implicate oxidative stress as a mediator of pulmonary hypertension (PH) and of the associated pathological changes to the pulmonary vasculature and right ventricle (RV). Increases in reactive oxygen species (ROS), altered redox state, and elevated oxidant stress have been demonstrated in the lungs and RV of several animal models of PH, including chronic hypoxia, monocrotaline toxicity, caveolin-1 knock-out mouse, and the transgenic Ren2 rat which overexpresses the mouse renin gene. Generation of ROS in these models is derived mostly from the activities of the nicotinamide adenine dinucleotide phosphate oxidases, xanthine oxidase, and uncoupled endothelial nitric oxide synthase. As disease progresses circulating monocytes and bone marrow-derived monocytic progenitor cells are attracted to and accumulate in the pulmonary vasculature. Once established, these inflammatory cells generate ROS and secrete mitogenic and fibrogenic cytokines that induce cell proliferation and fibrosis in the vascular wall resulting in progressive vascular remodeling. Deficiencies in antioxidant enzymes also contribute to pulmonary hypertensive states. Current therapies were developed to improve endothelial function, reduce pulmonary artery pressure, and slow the progression of vascular remodeling in the pulmonary vasculature by targeting deficiencies in either NO (PDE-type 5 inhibition) or PGI 2 (prostacyclin analogs), or excessive synthesis of ET-1 (ET receptor blockers) with the intent to improve patient clinical status and survival. New therapies may slow disease progression to some extent, but long term management has not been achieved and mortality is still high. Although little is known concerning the effects of current pulmonary arterial hypertension treatments on RV structure and function, interest in this area is increasing. Development of therapeutic strategies that simultaneously target pathology in the pulmonary vasculature and RV may be beneficial in reducing mortality associated with RV failure.
基金Supported by National Natural Science Foundation of China,No.81772001National Clinical Key Subject of China,No.41792113Technology Plan Program of Sichuan Provence,No.2015SZ0229,No.2016HH0067,No.2018JY0041and No.2019YJ0277
文摘BACKGROUND Abdominal paracentesis drainage(APD)is a safe and effective strategy for severe acute pancreatitis(SAP)patients.However,the effects of APD treatment on SAPassociated cardiac injury remain unknown.AIM To investigate the protective effects of APD on SAP-associated cardiac injury and the underlying mechanisms.METHODS SAP was induced by 5%sodium taurocholate retrograde injection in Sprague-Dawley rats.APD was performed by inserting a drainage tube with a vacuum ball into the lower right abdomen of the rats immediately after SAP induction.Morphological staining,serum amylase and inflammatory mediators,serum and ascites high mobility group box(HMGB)1,cardiac-related enzymes indexes and cardiac function,oxidative stress markers and apoptosis and associated proteins were assessed in the myocardium in SAP rats.Nicotinamide adenine dinucleotide phosphate oxidase activity and mRNA and protein expression were also examined.RESULTS APD treatment improved cardiac morphological changes,inhibited cardiac dysfunction,decreased cardiac enzymes and reduced cardiomyocyte apoptosis,proapoptotic Bax and cleaved caspase-3 protein levels.APD significantly decreased serum levels of HMGB1,inhibited nicotinamide adenine dinucleotide phosphate oxidase expression and ultimately alleviated cardiac oxidative injury.Furthermore,the activation of cardiac nicotinamide adenine dinucleotide phosphate oxidase by pancreatitis-associated ascitic fluid intraperitoneal injection was effectively inhibited by adding anti-HMGB1 neutralizing antibody in rats with mild acute pancreatitis.CONCLUSION APD treatment could exert cardioprotective effects on SAP-associated cardiac injury through suppressing HMGB1-mediated oxidative stress,which may be a novel mechanism behind the effectiveness of APD on SAP.
文摘Background： The calcium clearance and reactive oxygen species （ROS） generations in the coronary artery smooth muscle cells in chronic heart failure （HF） have not been fully investigated. Therefore, we attempted to understand the gene expressions underlying the mishandling of calcium clearance and the accumulations of ROS. Methods： We initially established an animal model of chronic HF by making the left anterior descending coronary artery ligation （CAL） in rats, and then isolated the coronary artery vascular smooth muscle cells from the ischemic and the nonischemic parts of the coronary artery vessels in 12 weeks after CAL operation. The intracellular calcium concentration and ROS level were measured using flow cytometry, and the gene expressions of sarco/endoplasmic reticulum Ca2＋-ATPase （SERCA2a）, encoding sarcoplasmic reticulum Ca2＋-ATPase 2a, encoding sodium-calcium exchanger （NCX）, andp47phox encoding a subunit of the nicotinamide adenine dinucleotide phosphate （NADPH） oxidase were examined using real-time quantitative reverse transcription polymerase chain reaction and Western blotting, respectively. Results： We found that the calcium accumulation and ROS generation in the coronary artery smooth muscle cells isolated from either the ischemic or the nonischemic part of the CAL coronary artery vessel were significantly increased irrespective of blood supply （all P 〈 0.01 ）. Moreover, these were accompanied by the increased expressions of NCX and p47phox, the decreased expression of S ERCA2a, and the increased amount of phosphorylated forms of p47phox in NADPH oxidase （all P 〈 0.05）. Conclusions： Our results demonstrated that the disordered calcium clearance and the increased ROS generation occurred in the coronary artery smooth muscle cells in rats with chronic HF produced by ligation of the left anterior descending coronary artery （CAL）, and which was found to be disassociated from blood supply, and the increased generation of ROS in the ceils was found to
基金This study was supported by a grant from the National Natural Science Foundation of China （No. 30830056 and No. U0932002）. Conflict of interests： None.
文摘Renal fibrosis is a common pathway of progressive renal diseases leading to end-stage renal disease regardless of the etiology. Accumulating evidence indicates that oxidative stress, resulting in generation of reactive oxygen species （ROS）, plays a critical role in the initiation and progression of fibrotic diseases. Nicotinamide adenine dinucleotide phosphate （NADPH） oxidase is the predominant enzyme source for ROS generation and is now recognized as a key mediator of cell proliferation and matrix accumulation in renal disease. Multiple stimuli and agonists, such as transforming growth factor , tumor necrosis factor, platelet derived growth factor, angiotensin II, hyperglycemia, oxidized low-density lipoprotein and albumin have been shown to alter the activity or expression of the NADPH oxidase and ultimately increase ROS production. ROS directly incites damage to biologically important macromolecules and leads to generation of the so-called advanced oxidation protein products （AOPPs） and advanced glycation end products, which are not only markers of oxidative stress but also cause renal injury. Targeting NADPH oxidase and/or reducing AOPPs production miaht be a novel strateav for the theraoeutic intervention of varietv of fibrotic kidney disorders.
基金Supported by The National Natural Science Foundation of China,No.81173393the Natural Science Foundation of Tianjin City,No.12YFJZJC00800+1 种基金the Scientific Research Foundation(No.WHM201222,FYM201114)the Innovation Team Program(No.WHTD201310)from Logistics University of the Chinese People’s Armed Police Forces
文摘Studies have demonstrated that reactive oxygen species(ROS) are closely related to inflammatory disorders. Nicotinamide adenine dinucleotide phosphate oxidase(NOX), originally found in phagocytes, is the main source of ROS in nonphagocytic cells. Besides directly producing the detrimental highly reactive ROS to act on biomolecules(lipids, proteins, and nucleic acids), NOX can also activate multiple signal transduction pathways, which regulate cell growth, proliferation, differentiation and apoptosis by producing ROS. Recently, research on pancreatic NOX is no longer limited to inflammatory cells, but extends to the aspect of pancreatic acinar cells and pancreatic stellate cells, which are considered to be potentially associated with pancreatitis. In this review, we summarize the literature on NOX protein structure, activation, function and its role in the pathogenesis of pancreatitis.
基金the State Key Basic Research and Development Plan ofChina (2003CB114300 and 2006CB100100)the National Natural ScienceFoundation of China (30170088 and 30370120)the Doctoral ProgramFoundation of the Educational Ministry of China (20020019030).
文摘Tobacco BY-2 suspension cells were used to study the chemical damage and its associated mechanisms caused by Cu^2＋. Treatment with 100 μmol/L Cu^2＋ generated a large amount of HzOz and thiobarbituric acid-reactive substances （TBARS） in cells. Using phospholipase D （PLD） specific inhibitor （1-butanol） or phosphatidic acid （PA）, we demonstrated that PLD plays an important role in the generation of H2O2 and TBARS. Semi-quantitative reverse-transcriptase polymerase chain reaction and enzyme activity assays with wild type and nicotinamide adenine dinucleotide phosphate （NADPH） oxidaseoverexpressing BY-2 cells revealed that PLD and PA are the key factors leading to NADPH oxidase activation, which is responsible for H2O2 and TBARS production induced by Cu^2＋. Moreover, the content of ascorbic acid （AsA）, an effective antioxidant, was sharply reduced in BY-2 cells exposed to excessive Cu^2＋. Furthermore, a significant downregulation of the enzymes of AsA biosynthesis and the antioxidant system was found. This evidence suggests that excessive Cu^2＋-elevated reactive oxygen species （ROS） production is caused by upregulated PLD that elevates the activity of NADPH oxidase and its collapsed antioxidant systems that scavenges ROS.
文摘Background Oxidative Stress and p38 mitogen-activated protein kinase （p38MAPK） play a vital role in renal fibrosis. Pioglitazone can protect kidney but the underlying mechanisms are less clear. The purpose of this study was to investigate the effect of pioglitazone on oxidative stress and whether the severity of oxidative stress was associated with the phosphorylation level of p38MAPK.
基金This study was sponsored by a grant from the Shandong Provincial Natural Science Foundation （No. Y2007C005）.
文摘Background The p22phox is a critical component of the superoxide-generating vascular nicotinamide adenine dinucleotide phosphate （NADPH） oxidase. Several polymorphisms in p22phox gene are studied for their association with cardiovascular diseases. However, no publication is available to assess the relation of 549C〉T polymorphism in p22pho~ gene to coronary artery disease （CAD） risk. This study was to investigate the effect of the p22phox gene 549C〉T polymorphism on CAD risk. Methods Hospital-based case-control study was conducted with 297 CAD patients and 343 healthy persons as the control group. Polymerase chain reaction and pyrosequencing using PSQ 96 MA Pyrosequencer （Biotage AB） were used to detect the polymorphisms. Multiple Logistic regression model was used to adjust the potential confounders and to estimate odds ratio （OR） with 95% confidence intervals （CIs）. Results The observed genotype frequencies of this polymorphism obeyed the Hardy-Weinberg equilibrium in both cases （P=0.439） and controls （P=-0.668）. The frequency of mutant genotypes （＇I-I-＋CT） in cases （41.08%） was higher than that in controls （36.73%） with an OR=1.20 （95% C1=0.87-1.65）. After the adjustment of the potential confounders, there was a significant association of the mutant genotypes with increased risk of CAD （OR=1.57, 95% C1=1.01-2.46, P=0.047）. Conclusions The mutant genotypes of the p22phox gene 549C〉T polymorphism had a significant effect on the increased risk of CAD in this studied population.
基金financially supported by the National Natural Science Foundation of China,No.81303115,81774042,81771353the Natural Science Foundation of Guangdong Province of China,No.S2013040016915+3 种基金the Science and Technology Program of Guangzhou City of China,No.201508020050,201604020003the Pearl River S&T Nova Program of Guangzhou,the Postdoctoral Foundation of China,No.BBK42913K09,201003345,BBH429151701a grant from the Hong Kong Scholar Program,Guangzhou University of TCM 2017 High Level University Construction Program,No.A1-AFD018171Z11096a grant from the Specialty Program of Guangdong Province Hospital of Traditional Chinese Medicine of China,No.YN2016MJ07,YN2015QN16,YN2015B2025
文摘Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxida- tive effects and has been used to treat cardiovascular and cerebrovascular diseases in China. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 （NOX2） was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 μM scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco＇s modified Eagle＇s medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 μM scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen, species in astrocytes subjected to ischemia-＇reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine （8-OHdG）, 4-hydroxy-2-nonenal （4-HNE） and 3-nitrotyr
基金Supported by the Plans for the Development of Traditional Chinese Medicine Science and Technology of Shandong Province(No.2011-203)
文摘Objective： To investigate the mechanism of Panax notoginseng saponins （PNS）, an effective component extracted from Panax notoginseng, on atherosclerotic plaque angiogenesis in atherosclerosis-prone apolipoprotein E-knockout （ApoE-KO） mice fed with high-fat, high-cholesterol diet. Methods： Twenty ApoE-KO mice were divided into two groups, the model group and the PNS group. Ten normal C57BL/6J mice were used as a control group. PNS （60 mg/kg） was orally administered daily for 12 weeks in the PNS group, The ratio of plaque area to vessel area was examined by histological staining. The tissue sample of aortic root was used to detect the CD34 and vascular endothelial growth factor （VEGF） expression areas by immunohistochemistry. The expression of VEGF and nicotinamide adenine dinucleotide phosphate oxidase subunit 4 （NOX4） were measured by reverse transcription polymerase chain reaction and Westem blotting respectively. Results： After treatment with PNS, the plaque areas were decreased （P〈0.05）. CD34 expressing areas and VEGF expression areas in plaques were significantly decreased （P〈0.05）. Meanwhile, VEGF and NOX4 mRNA expression were decreased after treatment with PNS, VEGF and NOX4 protein expression were also decreased by about 72% and 63%, respectively （P〈0.01）. Conclusion： PNS, which decreases VEGF and NOX4 expression, could alleviate plaque angiogenesis and attenuate atherosclerosis.
基金partially supported by Merit Review Award(I01RX-001964-01)from the US Department of Veterans Affairs Rehabilitation Research and Development Service(to YD)the National Natural Science Foundation of China(81501141)+1 种基金Beijing New Star of Science and Technology Program of China(xx2016061)Beijing Tongzhou District Financial Fund,and Scientific Research Common Program of Beijing Municipal Commission of Education,China(KM201610025028)(to XG)
文摘Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under normal circumstances, reactive oxygen species mediate a number of important cellular functions, including the facilitation of adaptive immunity. In pathogenic circumstances, however,excess reactive oxygen species generated by NOX promotes apoptotic cell death. In ischemic stroke, in particular, it has been shown that both NOX activation and derangements in glucose metabolism result in increased apoptosis. Moreover, recent studies have established that glucose, as a NOX substrate, plays a vital role in the pathogenesis of reperfusion injury. Thus, NOX inhibition has the potential to mitigate the deleterious impact of hyperglycemia on stroke. In this paper, we provide an overview of this research,coupled with a discussion of its implications for the development of NOX inhibition as a strategy for the treatment of ischemic stroke. Both inhibition using apocynin, as well as the prospect of developing more specific inhibitors based on what is now understood of the biology of NOX assembly and activation, will be highlighted in the course of our discussion.
基金Supported by the National Natural Science Foundation of China under GrantNo. 30871469the Zhejiang Province Natural Science Foundation of China under Grant No. Y306087
文摘The activity of plasma membrane （PM） nicotinamide adenine dinucleotide phosphate （NADPH） oxidase and its catalytic properties in rice was investigated under drought stress conditions. Drought stress led to decreased leaf relative water content （RWC） and, as a result of drought-induced oxidative stress, the activities of antioxidant enzymes increased significantly. More interestingly, the intensity of applied water stress was correlated with increased production of H2O2 and O2^- and elevated activity of PM NADPH oxidase, a key enzyme of reactive oxygen species generation in plants. Histochemical analyses also revealed increased H2O2 and O2^- production in drought-stressed leaves. Application of diphenylene iodonium （DPI）, an inhibitor of PM NADPH oxidase, did not alleviate drought-induced production of H2O2 and O2^-. Catalysis experiments indicated that the rice PM NADPH oxidase was partially fiavin-dependent. The pH and temperature optima for this enzyme were 9.8 and 40 ℃, respectively. In addition, drought stress enhanced the activity under alkaline pH and high temperature conditions. These results suggest that a complex regulatory mechanism, associated with the NADPH oxidase-H2O2 system, is involved in the response of rice to drought stress.
