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Objective To investigate the effects of angiotensin Ⅱ (Ang Ⅱ) or high glucose on the toll-like receptor 4 (TLR4) expression,inflammatory cytokines and fibrotic factors in human tubular epithelial cells (HK-2),revealing the innate immune-related pathogenesis of diabetic nephropathy (DN) which may have clinical implications.Methods Three TLR4 siRNA sequences were designed and synthetized.After transfection,the most effective siRNA was selected to use for further expriments.The experiment consisted of 2 parts.Part 1:Cells were divided into three groups:normal-glucose group (NG,5.5mmol/L glucose),mannose group (M,5.5 mmol/L glucose + 19.5 mmol/L mannose),High-glucose group (HG,25 mmol/L glucose),preliminary validated the effects of high glucose and high osmotic pressure.Part 2:Cells were divided into seven groups:NG group,HG group,Ang Ⅱ group,Ang Ⅱ + negative group,HG+ negative group,Ang Ⅱ + siRNA group and HG+ siRNA group.Real time PCR was used to analyze the mRNA expression of TLR4,myeloid differentiation factor 88 (MyD88),heat shock protein 47 (HSP47).Western blotting was used to observe the protein expression of TLR4,MyD88,HSP47,NF-κB,type Ⅳ collagen (ColⅣ).ELISA was used to detect the expression of monocyte chemotactic protein-1 (MCP-1) and interleukin-6 (IL-6).Results Compared with NG group,TLR4,MyD88,HSP47 mRNA and TLR4,MyD88,NF-κB,ColⅣ,HSP47 protein were highly expressed under high glucose or Ang Ⅱconditions (P ＜ 0.01),and the expression levels of MCP-1 and IL-6 also increased significantly (P ＜ 0.01).Compared with HG or Ang Ⅱ group,the above indicators were obviously inhibited in the TLR4 siRNA groups (P＜0.01).Comparison between blank vector transfected groups and HG group as well as Ang Ⅱ group indicated no statistic significance (P ＞ 0.05).Conclusions Both Ang Ⅱ and high glucose stimulate TLR4 expression,which result in the up-regulation of inflammatory and fibrotic factors in HK-2.Specific target of TLR4 gene silencing can block the TLR4 pathway that is activated by high glucose and Ang Ⅱ,and thus reduce the inflammatory and fibtogenic factors' release.TLR4 signal is the common innate immune response pathway which induces the release of inflammatory and fibrotic factors in HK-2 under high glucose or high angiotension conditions.
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Objective To investigate the involvement of mitogen-activated protein kinase(MAPK)and PI3K(phosphatidylinositol 3 kinase)/ Protein kinase B(Akt) signal transduction pathways in the mechanism of myocardium remodeling in patients with congestive heart failure(CHF).Methods Thirty nine patients of mitral valve disease with CHF were randomly selected and 30 cases of healthy persons were included as controls.Cardiac function parameters were measured by echocardiography.Concentration of AngⅡ in plasma and myocardial tissues was determined by radio immunoassay.Activity of PKC was determined by using competive prote in binding method,activity of MAPK was detected by the methods of immunoprecitipation.Immunoprecitipation was used to assay the protein expression and phosphorylation of PI3K and Akt(Protein kinase B),protein expression of C-FOS and ?-skeletal-actin in myocardial tissues.Results Pathological changes of myocardial tissues in CHF with valvular heart diseaseshowed typical myocardial remodeling.The hypertrophy was dominant at early stagy of CHF,while at end stage the characteristics include disordered alignament of the myocytes,the discontinuity and dissolving of cardiomyofibrills,destroyed subcellular organs,and the hyperplasia of interstitial tissue.AngⅡ concentration in plasm and myocardial tissues in patients with CHF was higher than those in the control group(P
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Objective To investigate the involvement of mitogen-activated protein kinase(MAPK)system and hypertrophy related genes in myocardial remodeling mechanism of patients with congestive heart failure(CHF).Methods Thirty-nine patients of mitral valve disease with CHF were randomly selected and 30 cases of healthy persons were included as controls.Cardiac function parameters were measured by echocardiography.Concentration of AngⅡ in plasma and myocardial tissues were determined by radio immunoassay.Immunoprecipitation was used to assay the protein expression and phosphorylation of c-jun NH2-terminal kinase(JNK),extracellular signal regulated kinase(ERK),P 38- mitogen-activated protein kinase(P 38-MAPK)in myocardial tissues;protein expression of c-myc,c-myb,c-jun was also determined by immunoprecipitation.Results Compared to the control group,the phosphorylation of ERK1/2 was obvious in heart function class Ⅱ group(P0.05);phosphorylation of JNK was obvious in CHF groups(P0.05);there was no expression in control group.Conclusion MAPK activated by renin angiotensin system may play an important role by causing the protein expression of c-myc,c-myb,c-jun in myocardial remodeling in patients with CHF.
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Objective To observe the changes of plasma adrenomedullin(ADM) and endothelin-1(ET-1),angiotension Ⅱ(Ang-Ⅱ) levels and their clinical significance in the patients with elderly hypertension(HPE).Methods The plasma levels of ADM and ET-1,Ang-Ⅱ were measured by radioimmunoassay in 136 patients with HPE compared with that of in 40 casers of health elders.Results The plasma levels of ADM and ET-1,Ang-Ⅱ were increased significantly in HPE compared with health elders(P
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Objective To investigate the protective effects and mechanism of shenmai injection(SMI) on cardiomyocytes injured by hydrogen peroxide(H 2O 2) or angiotension Ⅱ(AngⅡ). Methods According to the different concentrations of H 2O 2, AngⅡ,SMI,Vitamin C(VitC) added into the cardiomyocytes culture media(CCM), the cultures were divided into 15 groups. Lactate dehydrogenase(LDH ),malondialdehyde(MDA),superoxide dismutase (SOD) of CCM and cardiomyocytes viability(CMV), Na +-K +-ATPase,Ca 2+-ATPase?cardiomyocytes apoptosis rate(CMAR) ,nitrogen oxide(NO), nitrogen oxide synthesis enzyme(NOS),eNOS expression of cardiomyocytes were detected respectively .Results H 2O 2 or AngⅡ could decrease CMV, SOD, Na +-K +-ATPase,Ca 2+-ATPase,NOS,NO,eNOS expression and increase CMAR,LDH and MDA.SMI could lessen the changes of the items mentioned above ,which were caused by H 2O 2 or AngⅡ.The effects of SMI 10 ml/L were stronger than those of SMI 5 ml/L or VitC 50 mg/L.Conclusion SMI has a significant protective effect on cardiomyocyte injured by H 2O 2 or AngⅡ.
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Objective To evaluate the effectiveness of A type behavior in the development of essential hypertension.Methods The questionnaire of A type behavior were used to investigate 230 patients,divided into hypertension group (147) and no hypertension group (66). There are 89 patients and 14 patients of A type behavior in each group. 17 patients were eliminated. In some patients including A type (24 cases) and B type (26 cases), the level of norepinephrine (NE), renin (Ren) , angiotensin Ⅱ (AngⅡ), aldosterone (Ald) was tested. Results There were more A type behavior in hypertension group than no hypertension group, P 0.05).Conclusions The result confirmed that A type behavior has some influence on the development of essential hypetension and has some adverse effect on prognosis of patients.
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Objective:To study the role of rennin and angiotension Ⅱ in the developement of acute pancreatitis in rats.Methods:Forth-two Sprague-Dawley rats were divided into two groups randomly-control group,and acute pancreatitis group.Acute pancreatitis model was reproduced by closed duodenal loop technique.Plasma amylase.Plasma renin activity and angiotesion Ⅱ level were measured,pancreatic histopathology was examined with light microscopy. Results:In acute pancreatitis group,pancreatitis histopathology developed from edematous to bleeding and necrotizing pancreatitis,plasma amylase,plasma renin activity,and angiotesion Ⅱ level were increased as acute pancreatitis developed,but after 10h,the angiotesion Ⅱ level was increased sequentially and plasma renin activity was increased unsignificantly.Conclusion:Renin and angiotension Ⅱ played the important role in the developement of experimental acute pancreatitis.
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Objective: To investigate the cause of complications after naloxone (Nal) for administration analepsia of general anesthesia. Method: Thirty-six cases were randomly divided into group Ⅰ (n=12, Nal 0.004mg?kg~(-1)), group Ⅱ (n=12,Na1 0.002mg?kg~(-1)) and group Ⅲ (n=12,NS). The dosage was administrated intravenously in a bolus at the end of operation. The venous blood samples were taken respectively before anesthesia (T_1),Smin before and after the administration (T_1 ,T_3) to measure the plasma concentration of E and NE with high performance liquid chromatography,and those of A Ⅱ, ET and ANP with radioimmunoassay. The complications after the administration were observed. Result: Compared with T_1 and T_2, the plasma concentrations of A Ⅱ, E and NE obviously increased at T_3 in group Ⅰ and group Ⅱ (P
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Objective To investigate the protective effects of daidzein (DD) on myocardial hypertrophy and fibrosis induced by pressure overload in rats and to study its mechanism. MethodsMyocardial hypertrophy and fibrosis model of rats induced by pressure overload was prepared by constricting abdominal aorta. The operated rats were randomly divided into sham operated control group, aorta-constricted model group, and three DD groups (30, 60, and 120 mg/kg). Four weeks later, the heart-weight (HW), left ventricular weight (LVW), the ratio of HW/BW and LVW/BW (LVI), and the cardio-myocyte diameters (MD) after dying by HE color were measured. The content of collagen and nitric oxide (NO), the activity of calcineurin (CaN) and Na+, K+-ATPase, Ca2+-ATPase in the left ventricle were quantified with spectrophotometry. The angiotension Ⅱ (AngⅡ) in the left ventricle was messured with radioimmunoassay. Results In aorta-constricted model group, the ratio of HW/BW, LVI, and MD as well as the content of collagen and AngⅡ, the activity of CaN in the left ventricle was significantly increased, and Na+, K+-ATPase, Ca2+-ATPase activity and NO content in the left ventricle were obviously decreased. After treatment of the left ventricular with DD, NO content, Na+, K+-ATPase, Ca2+-ATPase activity were significantly increased, the content of collagen and of AngⅡ and the activity of CaN in the left ventricle and the ratio of HW/BW, LVI, and MD were significantly reduced. ConclusionDD has protective effects on ventricular remodeling in rats with myocardial hypertrophy and fibrosis induced by pressure overload and its mechanism may be related to raising NO content and reducing the level of AngⅡ and the activity of CaN.
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Aim To observe effects of Sodium tanshinoneⅡA sulfonate(STS) on angiotensionⅡ(AngⅡ)-induced cardiomyocyte hypertrophy and the expression of phosphorylated extracellular signal-regulated kinase1/2 (p-ERK1/2). Methods In the primary culture of neonatal rat cardiomyocytes, as indexes of cardiomyocyte hypertrophy, the total protein was determined by coomassie brilliant blue and protein synthesis rate was measured by [3H]-Leucine incorporation. The expression of p-ERK1/2 was assessed using Western blot and fluorescence microscope. Results ① The total protein and protein synthesis rate stimulated by Ang Ⅱ(1 ?mol?L-1)in the cardiomyocytes increased significantly in contrast to that of control; STS could effectively decrease the increased total protein level induced by Ang Ⅱand markedly inhibit synthesis of protein. ② AngⅡ(1 ?mol?L-1) had the effect of promoting activation of ERK1/2 and then appeared in nucleus rapidly. The translocation process of ERK1/2 induced by AngⅡ was blocked distinctly by STS. ③ Cardiomyocyte pretreated with Ang Ⅱ(1 ?mol?L-1)for 5 min, the p-ERK1/2 protein expression began to increase ,the peak effect was at 10 min. While pretreatment with STS(2, 10, 50 ?mol?L-1) ,Ang Ⅱ-induced increase in p-ERK1/2 were inhibited evidently. ④ In pretreatment of cardiomyocyte with STS in different doses for 30 min, STS was found to be able to inhibit the expression of p-ERK1/2 stimulated by AngⅡ in a dose-dependent manner. Conclusions The results suggested that activation of ERK1/2 might play an important role in cardiomyocytes hypertrophy induced by Ang Ⅱ,and the anti-hypertrophic effect of STS on cardiomyocyte hypertrophy induced by AngⅡ might be associated to its inhibitory effect on ERK signaling pathway.