苦荞麦总黄酮对软脂酸诱导EA.hy926细胞NO合成的影响

Effect of total flavonoids of tartary buckwheat on palmitic acid-induced NO synthesis in EA.hy926 cells

目的:研究苦荞麦总黄酮对软脂酸诱导EA.hy926细胞NO合成的影响。方法:将体外培养的EA.hy926细胞分为正常对照组、软脂酸诱导的胰岛素抵抗细胞模型组、苦荞麦总黄酮组、二甲双胍组。采用硝酸盐还原酶法检测各组细胞上清液中NO含量,逆转录聚合酶链式反应(RT-PCR)及Western blot法检测各组细胞eNOS mRNA和蛋白的表达。结果:胰岛素抵抗细胞模型组细胞上清液NO含量,细胞eNOS mRNA及蛋白表达与正常对照组相比明显下降(P<0.05)。苦荞麦总黄酮组与二甲双胍组细胞上清液NO含量,细胞eNOS mRNA及蛋白表达与模型组相比,明显增多(P<0.05)。苦荞麦总黄酮组和二甲双胍组相比,以上指标均无明显差异(P>0.05)。结论:苦荞麦总黄酮可有效促进软脂酸刺激下血管内皮细胞eNOS mRNA和蛋白的表达,从而增加NO的合成。

AIM： To observe the effects of total fla- vonoids of tartary buckwheat on NO synthesis in EA. hy026 ceils induced by palmitic acid. METHODS： EA. hy926 cells were cultured in vitro and randomly divided into control group, palmitic acid-induced insulin resistance group, total flavonoids of tartary buckwheat group and metformin group. The content of NO in supernatant was detected by nitrate reductase. The eNOS mRNA and protein expression levels were determined by RT-PCR and Western blotting, respec- tively. RESULTS： Compared with control group, the NO content in supernatant and the expression levels of eNOS mRNA and protein were significantly lower in insulin resist- ance group （ P 〈 0.05）. Compared with insulin resistance group, the NO content in supernatant, as well as the eNOS mRNA and protein expression markedly increased in both total flavonoids of tartary buckwheat group and metformin group （P 〈 0.05）, but there was no significant difference between the latter two groups （ P 〉 0.05）. CONCLUSION： Total flavonoids of tartary buckwheat effectively promotes the expression of eNOS mRNA and protein in endothelial cells under palmitic acid stimulation, thereby contributing to the NO synthesis.