瑞舒伐他汀调控Toll样受体4信号通路对H型高血压动物模型血管内皮功能及心肌内质网应激反应的影响研究

Study on the effects of Rosuvastatin on vascular endothelial function and response of myocardial endoplasmic reticulum stress in H-type hypertension animal model by regulating TLR4 signaling pathway

目的:探讨瑞舒伐他汀调控Toll样受体4(TLR4)信号通路对H型高血压动物模型血管内皮功能、心肌内质网应激反应的影响。方法:选取36只雄性SD大鼠,应用随机数表法将其分为对照组、模型组(H型高血压组)和干预组(H型高血压+瑞舒伐他汀干预),每组12只。对照组、模型组和干预组分别于给药前、给药后12周检测3组大鼠血压水平和血清同型半胱氨酸(Hcy)含量、血液中一氧化氮(NO)、内皮素-1(ET-1)、血管紧张素Ⅱ(Ang-Ⅱ)、血栓素A2(TXA2)等血管内皮因子水平,检测各组大鼠心肌组织C/EBP同源蛋白(CHOP)、激活作用转录因子6(ATF6)蛋白表达水平。检测TLR4 mRNA和蛋白及其下游核转录因子-κB(NF-κB)、肿瘤坏死因子-α(TNF-α)的表达水平。结果:给药前模型组和干预组大鼠血压和血清Hcy含量均显著高于对照组,差异有统计学意义(F=8.877,P<0.05),模型组和干预组大鼠血压水平和血清Hcy含量比较无明显差异;给药12周后对照组大鼠血压明显升高,与给药前比差异有统计学意义(F=314.536,P<0.05),血清Hcy含量无明显变化;模型组血压水平和血清Hcy含量均明显高于给药前和对照组(F=11.004,P<0.05),干预组血压水平和血清Hcy含量则均低于给药前和模型组(F=5.775,P<0.05)。给药12周后,模型组大鼠血液中NO含量明显低于对照组,ET-1、Ang-Ⅱ及TXA2均明显高于对照组,干预组的NO则明显高于模型组,ET-1、Ang-Ⅱ及TXA2均明显低于模型组和对照组(F=598.059,F=88.023,F=78.109,F=25.631;P<0.05)。模型组大鼠心肌组织CHOP、ATF6蛋白阳性着色和相对表达量均明显多于和高于对照组,干预组则明显少于和低于模型组和对照组(t=4.864,t=5.233,t=4.665,t=4.519,P<0.05)。模型组大鼠TLR4 mRNA和蛋白、NF-κB蛋白和TNF-α水平均明显高于对照组,干预组则明显低于模型组和对照组(F_(TLR4 mRNA)=98.936,F=123.321;F_(TLR4)=34.564,F=30.699;F_(NF-κB)=21.414,F=18.693;F_(TNF-α)=17.818,F=15.200;P<0.05)。在模型组和干预组中,TRL4蛋白水平与NO水平呈明显负相关,而与ET-1、Ang-Ⅱ和TXA2水平以及CHOP、ATF6蛋白水平呈明显正相关。结论:瑞舒伐他汀能够有效降低H型高血压大鼠的血压水平和血清Hcy含量,改善大鼠的血管内皮功能,减轻其心肌内质网应激水平,其作用机制可能与其对TLR4信号通路的抑制有关。

Objective:To investigate the effects of Rosuvastatin on vascular endothelial function and response of myocardial endoplasmic reticulum stress in H-type hypertension animal model by regulating toll like receptor 4(TLR4)signaling pathway.Methods:36 male SD rats were randomly divided into control group,model group(H-type hypertension group)and intervention group(H-type hypertension+Rosuvastatin intervention)according to random number table,with 12 rats in each group.The levels of blood pressure,and the serum homocysteine(Hcy),nitric oxide(NO),endothelin-1(ET-1),angiotensinⅡ(Ang-Ⅱ),thromboxane A2(TXA2)and other vascular endothelial factors,and the expression levels of C/EBP homologous protein(CHOP)and activation transcription factor 6(ATF6)of cardiac muscle tissue of three groups before and at the 12th week after they received medicine were detected.And then,the TLR4mRNA and protein,and the expression levels of downstream nuclear transcription factor-kB(NF-kB)and tumor necrosis factor-α(TNF-α)were further detected.Results:The levels of blood pressure and serum Hcy concentration of model group and intervention group were significantly higher than those of control group before medicine intervention(F=8.877,P<0.05).And the differences of those between model group and intervention group were not significant.After 12 weeks of medicine intervention,the blood pressure of control group was significantly higher than that pre medicine intervention(F=314.536,P<0.05),while the level of serum Hcy between pre and post intervention was not significant.The levels of blood pressure and serum Hcy of model group were significantly higher than those before medicine intervention and control group(F=11.004,P<0.05),while those of intervention group were significantly lower than them before medicine intervention and model group(F=5.775,P<0.05).After 12 weeks of medicine intervention,the NO concentration of model group was significantly lower than that of control group,and the levels of ET-1,Ang-Ⅱand TXA2 of model group were significantly higher than those of control group,and the NO level of intervention group was significantly higher than that of model group,and the levels of ET-1,Ang-Ⅱand TXA2 of intervention group were significantly lower than those of model group and control group(F=598.059,F=88.023,F=78.109,F=25.631,P<0.05),respectively.The positive staining and relative expression levels of CHOP and ATF6 protein in myocardial tissue of model group were significantly higher than those of control group,while those of intervention group were significantly lower than those of model group and control group(t=4.864,t=5.233,t=4.665,t=4.519,P<0.05),respectively.The TLR4 mRNA and protein,NF-kB protein and TNF-αof model group were significantly higher than those of control group, while those of intervention group were significantly lower than themof model group and control group (FTLR4 mRNA=98.936, F=123.321, FTLR4=34.564, F=30.699, FNF-κB=21.414, F=18.693,FTNF-α=17.818, F=15.200, P<0.05), respectively. In model group and intervention group, TRL4 protein level was negativelycorrelated with NO level, and was positively correlated with ET-1, Ang-Ⅱ, TXA2 levels, CHOP and ATF6 protein levels,respectively. Conclusion: Rosuvastatin can effectively reduce the levels of blood pressure and serum Hcy of H-typehypertensive rats, and improve the vascular endothelial function of them and relieve the level of myocardial endoplasmicreticulum stress. Its mechanism may be related to the inhibition from Rosuvastatin on TLR4 signaling pathway.