姜黄素对血管紧张素Ⅱ诱导血管平滑肌细胞增殖及氧化应激的影响
Curcumin inhibits AngⅡ-induced proliferation and oxidative stress in vascular smooth muscle cells

摘要：目的 观察姜黄素(curcumin, Cur)对血管紧张素Ⅱ(AngII)诱导血管平滑肌细胞(VSMCs)增殖及氧化应激的影响。方法 原代培养大鼠VSMCs细胞，MTT法测定不同浓度Cur对AngⅡ诱导VSMCs增殖的影响。并分别设对照组、AngⅡ干预组、20μmol/L Cur组及AngⅡ联用不同浓度Cur(5、10、20μmol/L)组，实时定量PCR和Western blot测定各组细胞诱导型一氧化氮合酶(iNOS)、p47phox mRNA与蛋白的表达；亚硝酸盐含量重氮化反应吸光测定法(Greiss assay)测定细胞内一氧化氮(NO)的表达；DCFH-DA氧化法测定细胞内活性氧(ROS)含量；黄嘌呤氧化酶法检测各试验组细胞上清液中超氧化物歧化酶(SOD)活性；分光光度计检测谷胱甘肽过氧化物酶(Gpx)活性。采用p47phox特异性siRNA干扰VSMCs p47phox的表达，并深入探讨Cur抑制AngⅡ诱导的VSMCs增殖及氧化应激的机制。结果 MTT法观察到Cur在0～80μmol/L浓度范围内对细胞活力无显著影响；Cur(5、10、20μmol/L)可以有效抑制AngⅡ诱导的VSMCs增殖。同时，Cur可有效抑制AngⅡ诱导的NO、iNOS、p47phox、ROS的高表达并有效提高SOD和Gpx的活性，且具有浓度依赖性。采用p47phox特异性siRNA下调p47phox表达，AngⅡ诱导的VSMCs内ROS生成减少。结论 Cur具有抑制AngⅡ诱导VSMCs的增殖及氧化应激作用。这一作用与减少iNOS诱导的NO合成，下调p47phox的表达抑制ROS产生、提高SOD和Gpx的活性，进而抑制AngⅡ诱导的VSMCs内氧化应激反应有关。
ABSTRACT: Objective To investigate the effect of curcumin (Cur) on AngⅡ-induced proliferation and oxidative stress of vascular smooth muscle cells (VSMCs).Methods Primary rat VSMCs were cultured and divided into control group,AngⅡ group, AngⅡ+Cur 5μmol/L group,AngⅡ+Cur 10μmol/L group, AngⅡ+Cur 20μmol/L group, and Cur 20μmol/L group. The proliferation of AngⅡ-induced VSMCs was measured by MTT assay. The mRNA and protein expressions of inducible nitric oxide synthase (iNOS) and p47phox were detected by real-time PCR and Western blot. Nitric oxide (NO) production was measured by Griess reaction. Production of intracellular reactive oxygen species (ROS) was measured by DCFH-DA staining, and the activities of superoxide dismutase (SOD) and glutathione peroxidase (Gpx) were detected by xanthine oxidase assay and visible spectrophotometer. small interfering RNA (siRNA) was used to silence the expression of p47phox to further explore the mechanism for Cur inhibiting the proliferation of AngⅡ-induced VSMCs and oxidative stress. Results VSMCs activities were not significantly affected by Cur at the concentration between 0 and 80μmol/L. Cur (5, 10 and 20μmol/L) significantly inhibited AngⅡ-induced proliferation of VSMCs. Cur had an inhibitory effect on the overexpression of NO, iNOS, p47phox and ROS in VSMCs and upregulated the activities of SOD and Gpx in a concentration-dependent manner. AngⅡ-induced ROS production in VSMCs was significantly attenuated by pretreatment with p47phox specific siRNA. Conclusion Cur can inhibit the proliferation and oxidative stress of AngⅡ-induced VSMCs