Effect and mechanism of Linggui Zhugan Decoction in regulating Sig1R on Ang Ⅱ-induced cardiomyocyte hypertrophy
This study aims to explore the mechanism of Linggui Zhugan Decoction(LGZGD)in inhibiting Angiotensin Ⅱ(AngⅡ)-induced cardiomyocyte hypertrophy by regulating sigma-1 receptor(Sig1R).The model of H9c2 cardiomyocyte hypertrophy induced by Ang Ⅱ in vitro was established by preparing LGZGD-containing serum and blank serum.H9c2 cells were divided into normal group,Ang Ⅱ model group,20％normal rat serum group(20％NSC),and 20％LGZGD-containing serum group.After the cells were incubated with Ang Ⅱ(1 μmol·L-1)or Ang Ⅱ with serum for 72 h,the surface area of cardiomyocytes was detected by phalloidine staining,and the activities of Na+-K+-ATPase and Ca2+-Mg2+-ATPase were detected by micromethod.The mitochondrial Ca2+levels were detected by flow cytometry,and the expression levels of atrial natriuretic peptide(ANP),brain natriuretic peptide(BNP),Sig1R,and inositol 1,4,5-triphosphate receptor type 2(IP3R2)were detected by Western blot.The expression of Sig1R was down-regulated by transfecting specific siRNA for investigating the efficacy of LGZGD-containing serum on cardiomyocyte surface area,Na+-K+-ATPase activity,Ca2+-Mg2+-ATPase activity,mitochondrial Ca2+,as well as ANP,BNP,and IP3R2 protein expressions.The results showed that compared with the normal group,Ang Ⅱ could significantly increase the surface area of cardiomyocytes and the expression of ANP and BNP(P＜0.01),and it could decrease the activities of Na+-K+-ATPase and Ca2+-Mg2+-ATPase,the concentration of mitochondrial Ca2+,and the expression of Sig1R(P＜0.01).In addition,IP3R2 protein expression was significantly increased(P＜0.01).LGZGD-containing serum could significantly decrease the surface area of cardiomyocytes and the expression of ANP and BNP(P＜0.05,P＜0.01),and it could increase the activities of Na+-K+-ATPase and Ca2+-Mg2+-ATPase,the concentration of mitochondrial Ca2+(P＜0.01),and the expression of Sig1R(P＜0.05).In addition,IP3R2 protein expression was significantly decreased(P＜0.05).However,after Sig1R was down-regulated,the effects of LGZGD-containing serum were reversed(P＜0.01).These results indicated that the LGZGD-containing serum could inhibit cardiomyocyte hypertrophy induced by Ang Ⅱ,and its pharmacological effect was related to regulating Sig1R,promoting mitochondrial Ca2+inflow,restoring ATP synthesis,and protecting mitochondrial function.
Linggui Zhugan Decoctioncardiomyocyte hypertrophymitochondria-associated ER membranesSigma-1 receptor(Sig1R)
万方数据
维普
