通心络对高脂饮食诱导内质网应激致小鼠血管内皮细胞凋亡的保护作用

Protective Effect of Tongxinluo on Vascular Endothelial Cell Apoptosis Induced by High-Fat Diet-Induced Endoplasmic Reticulum Stress in Mice

目的探讨通心络(TXL)对高脂喂养小鼠肥胖模型内质网应激(ERs)相关蛋白的调节及细胞凋亡的干预作用。方法将5-6周龄C57BL/6J小鼠随机分为低脂对照组(LFD+CMC)、模型组(HFD+CMC)和通心络组(HFD+TXL),18周后检测小鼠体质量和血脂水平。制备小鼠离体肠系膜动脉血管环,进行血管张力测试,比较各组血管张力的变化。RT-PCR检测小鼠肠系膜动脉内质网应激相关因子GRP78、PERK、CHOP及凋亡相关因子Bax、Bcl-2 mRNA表达;用同型半胱氨酸(Hcy)建立细胞损伤模型,将HUVEC分为正常对照组(control group)、模型组(Hcy group,2 mmol·L^(-1)Hcy)、通心络组(TXL组,200μg·mL^(-1)通心络),检测各组GRP78,Caspase-3,Caspase-7,Caspase-9蛋白表达情况。结果与LFD组比较,HFD组小鼠血总胆固醇(TC)、甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C)水平显著升高(P<0.01);与HFD组比较,TXL组小鼠TC、TG、LDL-C水平显著降低(P<0.05);在加入去甲肾上腺素(NE)诱发最大收缩程度后,按浓度依次加入乙酰胆碱,与LFD组相比,HFD组小鼠肠系膜动脉舒张功能明显受损,TXL组小鼠肠系膜动脉舒张功能较HFD组有明显改善(P<0.01);与HFD组相比,TXL组的GRP78、PERK、CHOP、Bax mRNA表达下调(P<0.05),Bcl-2 mRNA表达上调(P<0.01);与正常对照组比较,Hcy组细胞生存活性明显降低;HUVEC细胞Caspase-3,Caspase-7,Caspase-9蛋白表达上调(P<0.05);与模型组比较,通心络组GRP78及凋亡相关蛋白表达下调(P<0.05)。结论通心络可改善肥胖小鼠血脂水平,缓解内质网应激,并通过抗凋亡途径发挥血管保护作用。

Objective To discover the effect of Tongxinluo(TXL) on the regulation of endoplasmic reticulum stress(ERs)-related proteins and the intervention of apoptosis in a high-fat fed mouse model of obesity. Methods The 5-6 weeks old C57 BL/6 J mice were randomly divided into low-fat control group(LFD + CMC), model group(HFD + CMC)and Tongxinluo group(HFD + TXL), and the body weight and lipid level of the mice were measured after 18 weeks. The expression of GRP78, PERK, CHOP and apoptosis-related factors Bax and Bcl-2 mRNA were detected by RT-PCR.The expression of GRP78, Caspase-3, Caspase-7 and Caspase-9 in the control group, the model group(Hcy group, 2 mmol·L^(-1) Hcy) and the TXL group(200 μg·mL^(-1) TXL) were measured. Results Compared with the LFD group, the levels of total cholesterol(TC), triglyceride(TG) and low-density lipoprotein cholesterol(LDL-C) were significantly higher in the HFD group(P < 0.01);compared with the HFD group, the levels of TC, TG and LDL-C were significantly lower in the TXL group(P < 0.05);after the addition of norepinephrine(NE) to induce the maximum degree of contraction, the diastolic function of mesenteric arteries was significantly improved in the TXL group compared with the HFD group according to the concentration of After the addition of Ach in sequence, the diastolic function of mesenteric arteries was significantly impaired in the HFD group compared with the LFD group, and significantly improved in the TXL group compared with the HFD group(P < 0.01);compared with the HFD group, the mRNA expression of GRP78,PERK, CHOP, and Bax was downregulated in the TXL group(P < 0.05), and Bcl-2 mRNA expression was upregulated(P < 0.01);cell survival activity was significantly reduced in the Hcy group compared with the normal control group;Caspase-3, Caspase-7, Caspase-9 protein expression was upregulated in HUVEC cells(P < 0.05);GRP78 and apoptosis-related protein expression was downregulated in the TXL group compared with the model group(P < 0.05).Conclusion Tongxinluo can improve blood lipid levels, relieve endoplasmic reticulum stress, and exert vascular protection through anti-apoptotic pathway.