OBJECTIVETo explore the relationship between the expression of endothelial nitric oxide synthase (eNOS) and NADPH oxidase (NOX) in the lungs of mice treated by chronic hypoxic exposure.

METHODSThirty male wild-type (WT) C57Bl/6 mice and thirty male eNOS-knockout (KO) C57BL/6 mice were randomly divided into normoxic groups (exposed to normoxia for 7 days or 21 days), hypoxic groups (exposed to 10% oxygen for 7 days or 21 days), and treatment groups (exposed to 10% oxygen and orally administrated 10 mmol/L 4-hydroxy TEMPO in drinking water for 7 days or 21 days) (n=6 in each group). The remodeling of the small pulmonary arteries was evaluated by the percentage of media wall thickness (MT%). The weight ratio of right ventricle to left ventricle plus septum (RV/[LV+S]) was calculated to evaluate the hypertrophy of right ventricle. Real-time PCR was used to measure the mRNA expression of NOX2, NOX4, and eNOS in mouse lungs. ELISA was used to determine the concentration of reactive oxygen species (ROS) in mouse lungs.

RESULTSIn WT mice and KO mice, the hypoxic groups had significantly increased pulmonary vascular remodeling and RV/[LV+S] compared with the normoxic and treatment groups (P<0.05), but there were no significant differences between the normoxic and treatment groups (P>0.05). In WT mice, the hypoxic and treatment groups had significantly lower ROS concentrations than the normoxic group (P<0.05), but there were no significant differences between the hypoxic and treatment groups (P>0.05). In WT mice, the mRNA expression of eNOS, NOX2, and NOX4 was significantly higher in the hypoxic group than in the normoxic group (P<0.05), and 4-hydroxy TEMPO reversed their over-expression. In the normoxic group, the KO mice had significantly higher NOX2 and NOX4 mRNA expression than the WT mice (P<0.05); in KO mice, the hypoxic group showed no significant changes in NOX4 mRNA expression (P>0.05), but had significantly reduced NOX2 mRNA expression (P<0.05), as compared with the normoxic group; the treatment group had reduced expression of NOX2 mRNA expression and increased NOX4 mRNA expression (P<0.05), as compared with the hypoxic group.

CONCLUSIONSeNOS plays a key role in the regulation of expression of NOX2 and NOX4 in the lungs exposed to hypoxia. It suggests that NOX and eNOS may physically interact with one another in pulmonary vascular remodeling induced by chronic hypoxia.

Animals ; Chronic Disease ; Hypoxia ; enzymology ; Lung ; enzymology ; Male ; Membrane Glycoproteins ; genetics ; physiology ; Mice ; Mice, Inbred C57BL ; NADPH Oxidase 2 ; NADPH Oxidase 4 ; NADPH Oxidases ; genetics ; physiology ; Nitric Oxide Synthase Type III ; genetics ; physiology ; RNA, Messenger ; analysis

OBJECTIVETo investigate the inhibitory potential of aldosterone antagonist on NOX4 protein expression in hepatic fibrosis by using a rat model of carbon tetrachloride (CCl4)-induced hepatotoxicity.

METHODSTwenty-four male Wistar rats were randomly divided into three equal groups: fibrosis model group (receiving three subcutaneous injections per week of 2.5 ml/kg 40% CCl4); spironolactone (Sp)-treated fibrosis model group (receiving CCl4 regimen plus three injections per day of 20 mg/kg Sp in olive oil); negative-treatment fibrosis model group (receiving CCl4 regimen plus three injections per day of olive oil alone). Unmanipulated rats (receiving no CCl4 and no supplemental treatments) served as normal controls. After 4 weeks, liver histology was carried out to assess cytotoxicity (by hematoxylin-eosin staining), fibrosis (by Masson staining and METAVIR scoring), and NOX4 protein expression (by immunohistochemistry). In addition, in vitro analyses of immortalized rat hepatic stellate cells, HSC-T6, were performed to evaluate dose-response (10-9, 10-7 and 10-5 mol/L) and time-response (6, 12 and 24 h) of aldosterone agonist (Ald) and an aldosterone antagonist, eplerenone (EPLE). Effects on NOX4 protein expression were evaluated by western blotting.

RESULTSThe fibrosis model group showed significantly more fibrosis than the normal control group (16.060 +/- 0.300 vs. 2.471 +/- 0.160, P = 0.000]; however, the Sp-treated fibrosis model group showed significantly less CCl4-induced fibrosis (5.761 +/- 0.152 vs. model: 16.060 +/- 0.300, P = 0.000). The fibrosis model group also showed significantly higher NOX4 protein expression in liver tissues than the normal control group (7.231 +/- 0.211 vs. 1.350 +/- 0.252, P = 0.000), and the Sp-treated fibrosis model tissues showed significantly less CCl4-induced up-regulated NOX4 protein expression (4.270 +/- 0.242 vs. model: 7.231 +/- 0.211, P = 0.000]. Ald induced up-regulated NOX4 protein expression in HSC-T6 cells in dose- and concentration-dependent manners, with the peak expression being induced by the 10-5 mol/L concentration and 24 h exposure. The Ald-treated cells expressed significantly more NOX4 protein than the untreated control cells (0.710 +/- 0.011 vs. 0.316 +/- 0.015, P = 0.000]. and the EPLE-treated cells showed significantly less Ald-induced up-regulated NOX4 expression (0.615 +/- 0.014 vs. 0.710 +/- 0.011, P = 0.000].

CONCLUSIONAldosterone antagonists inhibit the fibrosis-induced NOX4 protein expression in rat hepatic cells.

Animals ; Cell Line ; Liver Cirrhosis, Experimental ; metabolism ; Male ; Mineralocorticoid Receptor Antagonists ; pharmacology ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Rats ; Rats, Wistar

The purpose of the present study was to determine the effects of resveratrol on hypoxia-induced oxidative stress and proliferation in pulmonary artery smooth muscle cells (PASMCs) and the underlying mechanism. Primary rat PASMCs were isolated and cultured in vitro and pretreated with different concentrations of resveratrol (10, 20, and 40 µmol/L) or the NADPH oxidase (NOX) inhibitor VAS2870 (10 µmol/L) for 0.5 h. The cells were then cultured under normoxia (21% O
Animals ; Cell Proliferation ; Cells, Cultured ; Hypoxia ; Myocytes, Smooth Muscle ; NADPH Oxidase 4 ; Oxidative Stress ; Pulmonary Artery ; Rats ; Reactive Oxygen Species ; Resveratrol/pharmacology* ; Signal Transduction

OBJECTIVE: To investigate the mechanism of high glucose affecting the apoptosis of schwann cells through Nox4 NADPH oxidase. METHODS: The schwann cells of newborn Wistar rats were cultured in vitro. The cultured cells were divided into four groups: control group, high-glucose group, NOX4 siRNA group and control siRNA group (n=10). The WST-1 method was used to detect the cell vitality, and the DCFH-DA method was used to detect the contents of intracellular reactive oxygen free radicals (ROS). Nox4 and Caspase3 mRNA expressions were detected by real-time fluorescence quantitative RT-PCR. Nox4 and Caspase3 protein expressions were determined by Western blot. RESULTS: High glucose culture up-regulated Nox4 mRNA and protein expressions of schwann cells, decreased activity of schwann cells, increased intracellular ROS content, and promoted apoptosis by increasing Caspase3 mRNA and protein expressions. NOX4 siRNA blocked the accumulation of ROS in the high glucose cultured schwann cells, and reduced the damage of glucose on cell viability, by inhibiting NOX4 gene expression. NOX4 siRNA also reduced cell apoptosis by down-regulating Caspase3 mRNA and protein expressions. CONCLUSION Nox4 was involved in the hyperglycemic-induced apoptosis of schwann cells through ROS. The regulation of Nox4 expression or function might be a new way to treat diabetic peripheral neuropathy.
Animals ; Apoptosis ; Caspase 3 ; metabolism ; Cells, Cultured ; Culture Media ; Glucose ; NADPH Oxidase 4 ; metabolism ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism ; Schwann Cells ; cytology ; metabolism

The aim of the present study is to investigate the protective effect of chrysin (5,7-dihydroxyflavone) on right ventricular remodeling in a rat model of monocrotaline-induced pulmonary arterial hypertension (PAH). PAH rats were induced by a single injection of monocrotaline (60 mg x kg(-1), sc) and were administered with chrysin (50 or 100 mg x kg(-1) x d(-1)) for 4 weeks. At the end of experiment, the right ventricular systolic pressure (RVSP) and mean pulmonary artery pressure (mPAP) were monitored via the right jugular vein catheterization into the right ventricle. Right ventricle (RV) to left ventricle (LV) + septum (S) and RV to tibial length were calculated. Right ventricular morphological change was observed by HE staining. Masson's trichrome stain was used to demonstrate collagen deposition. The total antioxidative capacity (T-AOC) and malondialdehyde (MDA) levels in right ventricle were determined according to the manufacturer's instructions. The expressions of collagen I, collagen III, NADPH oxidase 4 (NOX4) and nuclear factor-kappa B (NF-κB) were analyzed by immunohistochemisty, qPCR and (or) Western blot. The results showed that chrysin treatment for 4 weeks attenuated RVSP, mPAP and right ventricular remodeling index (RV/LV+S and RV/Tibial length) of PAH rats induced by monocrotaline. Furthermore, monocrotaline-induced right ventricular collagen accumulation and collagen I and collagen III expression were both significantly suppressed by chrysin. The expressions of NOX4, NF-κB and MDA contents were obviously decreased, while the T-AOC was significantly increased in right ventricule from PAH rats with chrysin treatment. These results suggest that chrysin ameliorates right ventricular remodeling of PAH induced by monocrotaline in rats through its down-regulating of NOX4 expression and antioxidant activity, and inhibiting NF-κB expression and collagen accumulation.
Animals ; Blotting, Western ; Collagen ; metabolism ; Disease Models, Animal ; Flavonoids ; pharmacology ; Heart Ventricles ; drug effects ; metabolism ; Hypertension, Pulmonary ; chemically induced ; metabolism ; Monocrotaline ; toxicity ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; NF-kappa B ; metabolism ; Rats ; Ventricular Remodeling ; drug effects

OBJECTIVETo investigate the protective effects of rutaecarpine (Rut) on right ventricular remodeling in rats with monocrotaline-induced pulmonary hypertension (PH).

METHODForty-eight SD rats were fed adaptively for 1 week and then were randomly divided into the following 4 groups (n = 12): normal control group, monocrotaline (MCT) treatment group, MCT treatment with Rut (20 mg/kg)group and MCT treatment with Rut (40 mg/kg) group. PH rats were induced by a single injection of monocrotaline (60 mg/kg, sc) and were administered with Rut (20 or 40 mg/kg/d) for 4 weeks. At the end of experiment, the right ventricular systolic pressure (RVSP) and mean pulmonary artery pressure (mPAP) were monitored via the right jugular vein catheterization into the right ventricle. The ratio of right ventricle (RV) to left ventricle (LV) + septum (S) and the ratio of RV to tibial length were calculated. Right ventricular morphological changes were deserved by HE staining. Masson's trichrome staining was used to display collagen deposition. The total antioxidative capacity (T-AOC) and malondialdehyde (MDA) levels in right ventricle were determined according to the manufacturer's instructions. mRNA and protein expression levels of NOX4, collagen I and collagen III were analyzed by immunohistochemisty, real-time PCR and Western blot.

RESULTSThe results showed that Rut treatment for 4 weeks attenuated RVSP, mPAP and right ventricular remodeling index (RV/LV + S and RV/Tibial length) of PH rats induced by monocrotaline. Furthermore, the right ventricular collagen deposition and collagen I and collagen I expression induced by MCT were both significantly suppressed by Rut. The expression levels of NOX4 and MDA were obviously decreased, while the T-AOC was significantly increased in right ventricular from PH rats treated with Rut.

CONCLUSIONThese results suggested that Rut ameliorates the right ventricular remodeling in rats with PH induced by MCT through down-regulating of NOX4 expression and collagen accumulation.

Animals ; Antioxidants ; metabolism ; Heart Ventricles ; metabolism ; Hypertension, Pulmonary ; chemically induced ; drug therapy ; Indole Alkaloids ; pharmacology ; Male ; Malondialdehyde ; metabolism ; Monocrotaline ; adverse effects ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Quinazolines ; pharmacology ; Rats ; Ventricular Remodeling ; drug effects

OBJECTIVETo investigate the effect of losartan in regulating oxidative stress and the underlying mechanism in mice with ventilator-induced lung injury.

METHODSThirty-six male C57 mice were randomly divided into control group, losartan treatment group, mechanical ventilation model group, and ventilation plus losartan treatment group. After the corresponding treatments, the lung injuries in each group were examined and the expressions of caveolin-1 and NOX4 in the lung tissues were detected.

RESULTSThe mean Smith score of lung injury was significantly higher in mechanical ventilation model group (3.3) than in the control group (0.4), and losartan treatment group (0.3); the mean score was significantly lowered in ventilation plus losartan treatment group (2.3) compared with that in the model group (P<0.05). The expressions of caveolin-1 and NOX4 were significantly higher in the model group than in the control and losartan treatment groups (P<0.05) but was obviously lowered after losartan treatment (P<0.05). Co-expression of caveolin-1 and NOX4 in the lungs was observed in the model group, and was significantly decreased after losartan treatment.

CONCLUSIONLosartan can alleviate ventilator-induced lung injury in mice and inhibit the expression of caveolin-1 and NOX4 and their interaction in the lungs.

Animals ; Caveolin 1 ; metabolism ; Losartan ; pharmacology ; Lung ; metabolism ; physiopathology ; Male ; Mice ; Mice, Inbred C57BL ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Oxidative Stress ; Respiration, Artificial ; Ventilator-Induced Lung Injury ; drug therapy ; metabolism

Sustained activation of β adrenergic receptor (βAR) leads to pathologic cardiac hypertrophy. However, the related mechanisms still remain unclear. In this study, we observe how N-acetylcysteine (NAC) affects the oxidative stress and calcium/calmodulin-dependent protein kinase II (CaMKII) expression in heart of isoproterenol (ISO)-stimulated rats, and investigate whether oxidative stress and CaMKII contribute to the development of sustained βAR-stimulated cardiac hypertrophy. Healthy male Wistar rats were randomly separated into 4 groups: control (CTRL), ISO-treated (ISO), control with NAC supplement (CTRL+NAC) and ISO-treated with NAC supplement (ISO+NAC) groups (6 rats in each group). Systolic blood pressure (SBP) was measured in awake rats with the tail-cuff method every week for two weeks. Heart weight/body weight ratio (HW/BW) and HE staining were used for the detection of myocardial hypertrophy. Myocardial mitochondrial reactive oxygen species (ROS) levels were measured by DCF fluorometry. The expressions of activated-CaMKII (p-CaMKII/CaMKII) and NADPH oxidase 4 (NOX(4)) were determined by Western blot analysis. The results showed that ISO-treated (i.p., daily 3 mg/kg, 2 weeks) rats developed an obvious cardiac hypertrophy as expressed by increases of HW/BW and myocyte cross-section area. Cardiac mitochondrial ROS level was significantly enhanced in ISO group as compared to CTRL group (P < 0.05). The expressions of NOX(4) and p-CaMKII in ISO group were also up-regulated as compared to CTRL group (1.4 and 1.6 times of CTRL, respectively, P < 0.05). NAC supplement significantly suppressed the hypertrophic development of heart in ISO-stimulated rats. The cardiac mitochondrial ROS level showed a significant decrease in rats of ISO+NAC group (P < 0.05 vs ISO). In accordance with this, ISO+NAC group rats also showed marked reductions in the expressions of NOX(4) and p-CaMKII/CaMKII compared to ISO group rats (P < 0.05). There were no significant differences of the detected indices between the rats from CTRL+NAC and CTRL groups. SBP showed no differences among four groups. These results suggest that both oxidative stress and CaMKII play important roles in sustained βAR-stimulated cardiac hypertrophy. NAC may suppress ISO-induced cardiac hypertrophy by down-regulating the expression of activated-CaMKII, and by reducing the level of oxidative stress originated from mitochondria and NADPH oxidase pathways.
Acetylcysteine ; pharmacology ; Animals ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; metabolism ; Cardiomegaly ; physiopathology ; Isoproterenol ; pharmacology ; Male ; Mitochondria, Heart ; metabolism ; Myocardium ; pathology ; NADPH Oxidase 4 ; NADPH Oxidases ; metabolism ; Oxidative Stress ; Rats ; Rats, Wistar ; Reactive Oxygen Species ; metabolism ; Receptors, Adrenergic, beta ; metabolism

OBJECTIVEThe roles of cerebrovascular oxidative stress in vascular functional remodeling have been described in hindlimb-unweighting (HU) rats. However, the underlying mechanism remains to be established.

METHODSWe investigated the generation of vascular reactive oxygen species (ROS), Nox2/Nox4 protein and mRNA levels, NADPH oxidase activity, and manganese superoxide dismutase (MnSOD) and glutathione peroxidase-1 (GPx-1) mRNA levels in cerebral and mesenteric smooth muscle cells (VSMCs) of HU rats.

RESULTSROS production increased in cerebral but not in mesenteric VSMCs of HU rats compared with those in control rats. Nox2 and Nox4 protein and mRNA levels were increased significantly but MnSOD/GPx-1 mRNA levels decreased in HU rat cerebral arteries but not in mesenteric arteries. NADPH oxidases were activated significantly more in cerebral but not in mesenteric arteries of HU rats. NADPH oxidase inhibition with apocynin attenuated cerebrovascular ROS production and partially restored Nox2/Nox4 protein and mRNA levels, NADPH oxidase activity, and MnSOD/GPx-1 mRNA levels in cerebral VSMCs of HU rats.

CONCLUSIONThese results suggest that vascular NADPH oxidases regulate cerebrovascular redox status and participate in vascular oxidative stress injury during simulated microgravit.

Acetophenones ; Animals ; Cerebral Arteries ; metabolism ; Glutathione Peroxidase ; metabolism ; Hindlimb Suspension ; Male ; Membrane Glycoproteins ; metabolism ; Mesenteric Arteries ; metabolism ; Myocytes, Smooth Muscle ; metabolism ; NADPH Oxidase 2 ; NADPH Oxidase 4 ; NADPH Oxidases ; antagonists & inhibitors ; metabolism ; Rats, Sprague-Dawley ; Reactive Oxygen Species ; Superoxide Dismutase ; metabolism

OBJECTIVETo observe the effect of sesamin (Ses) on pulmonary vascular remodeling in rats with monocrotaline ( MCT)-induced pulmonary hypertension (PH).

METHODTotally 48 male Sprague-Dawley (SD) rats were fed adaptively for one week and then divided into the normal control group, the MCT group, the MCT +Ses (50 mg x kg(-1)) group and the MCT + Ses (100 mg x kg(-1)) group, with 12 rats in each group. The PH rat model was induced through the subcutaneous injection with MCT(60 mg x kg(-1)). After the administration for four weeks, efforts were made to measure the right ventricular systolic pressure( RVSP) and mean pulmonary artery pressure (mPAP) through right jugular vein catheterization, and isolate right ventricle( RV) and left ventricle( LV) +septum (S) and measure their length to calculate RV/ ( LV + S) and ratio of RV to tibial length. Pathologic changes in arterioles were observed by HE staining. Masson's trichrome stain was used to demonstrate changes in collagen deposition of arterioles. The alpha-smooth muscle actin (alpha-SMA) expression in pulmonary arteries was measured by immunohistochemisty. The total antioxidative capacity (T-AOC) and malondialdehyde (MDA) content in pulmonary arteries were determined by the colorimetric method. The protein expressions of collagen I, NOX2 and NOX4 were analyzed by Real-time PCR and Western blot.

RESULTAfter the administration for 4 weeks, Ses could attenuate RVSP and mPAP induced by MCT, RV/ (LV + S) and ratio of RV to Tibial length, alpha-SMA and collagen I expressions and remodeling of pulmonary vessels and right ventricle. Meanwhile, Ses could obviously inhibit the expressions of NOX2, NOX4 and MDA content and increase T-AOC.

CONCLUSIONSesamin could ameliorate pulmonary vascular remodeling induced by monocrotaline in PH rats. Its mechanism may be related to expressions of NOX2 and NOX4 expression and reduction in oxidative stress injury.

Animals ; Dioxoles ; administration & dosage ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Hypertension, Pulmonary ; drug therapy ; enzymology ; genetics ; physiopathology ; Lignans ; administration & dosage ; Lung ; blood supply ; enzymology ; metabolism ; Male ; Membrane Glycoproteins ; genetics ; metabolism ; Monocrotaline ; adverse effects ; NADPH Oxidase 2 ; NADPH Oxidase 4 ; NADPH Oxidases ; genetics ; metabolism ; Pulmonary Artery ; drug effects ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Vascular Remodeling ; drug effects