Protective Effect Of Tongxinluo On Vascular Endothelial Cells Induced By Endoplasmic Reticulum Stress

1.Protective Effect of Tongxinluo on Vascular Endothelial Cells of C57BL/6J Mice Fed with High FatObjective: To observe the endothelium-dependent vasodilation function of mesenteric artery in obese mice fed with high fat,and the expression of endoplasmic reticulum stress-related factors Glucoseregulated protein 78(GRP78),protein kinase R-like endoplasmic reticulum kinase(PERK),eukaryotic translation initiation factor 2α(e IF2α)and homologous protein C/EBP(CHOP).To explore the protective effect of Tongxinluo(TXL)on vascular endothelium of obese mice and its possible mechanism of action to improve Endoplasmic Reticulum Stress response(ERs).Methods: 60 male C57BL/6J mice were randomly divided into normal control group(CON),model group(HFD),Tongxinluo group(TXL)and simvastatin group(positive control),with 15 mice in each group.The mice in CON group were fed with low-fat diet,and the mice in HFD group,TXL group and simvastatin group were fed with high-fat diet.The mice in TXL group were given traditional Chinese medicine TXL suspension at a dose of 1.5 g/kg,and the mice in simvastatin group were given simvastatin 5 mg/kg/day by oral gavage daily.The body weight of mice in each group was measured every week,and the level of serum lipids was detected after 16-week-treatment.The isolated mesenteric artery rings of mice were prepared,and the vascular tension was measured,and the endothelium-dependent vasodilation function of mesenteric artery in each group was compared.The mRNA expression of ERs-related factors GRP78,PERK,e-IF2α and CHOP in mesenteric artery was detected by RT-PCR,and the protein expression of GRP78 and CHOP was detected by Western Blot.Results:1.General condition of mice in each group.In general,the mice in CON group had normal diet,free movement and shiny coat,while mice in HFD group had poor mental state,slow movement,dark,greasy and unsmooth hair color,and the body weight gain was the most obvious alteration.The above symptoms in TXL group and simvastatin group were improved,and the body weight was lighter than that in HFD group and HFD group(P<0.01).2.The levels of blood lipids in each group of mice.The levels of serum total cholesterol(TC),triglyceride(TG)and low density lipoprotein cholesterol(LDL-c)in HFD group were significantly higher than those in CON group,while the levels of TC,TG and LDL-C in TXL group and simvastatin group were lower than those in HFD group.3.The endothelium-dependent diastolic function in each group of mice.After the maximal contraction induced by norepinephrine(NE).Acetylcholine(Ach)was added successively according to the concentration of endothelium-dependent vasodilation in each group.Compared with CON group,the mesenteric artery diastolic function of HFD group was significantly impaired,and the mesenteric artery diastolic function of TXL group and simvastatin group was significantly better than that of HFD group.4.RT-PCR analysis of endoplasmic reticulum stress-related gene expression in mouse vascular tissueCompared with the HFD group,the expression of GRP78,PERK,e IF2α and CHOP mRNA in the TXL group was down-regulated(P<0.05).5.Western blot analysis of GRP78 and CHOP protein expression in mouse vascular tissueCompared with the CON group,the expressions of GRP78 and CHOP protein in the HFD group were up-regulated(P<0.05);compared with the HFD group,the expressions of GRP78 and CHOP protein in the TXL group and simvastatin group were down-regulated(P<0.05).Conclusion: Tongxinluo has a protective effect on the damage of vascular endothelial cells in obese mice,and its mechanism may be related to the repression of endoplasmic reticulum stress.2.Tongxinluo on Human Umbilical Vein Endothelial Cells Injured by HomocysteineObjective: To observe the protective effect and mechanism of TXL on homocysteine(Hcy)-induced injury of human umbilical vein endothelial cells(HUVEC).Methods: HUVEC cells were cultured in vitro,and the cell injury model was established by Hcy.HUVEC cells were divided into three groups: Control group,Hcy group and TXL group.MTS method was used to detect the survival activity of cells in each group,and Western blot analysis was used to detect the protein expression levels of GRP78,Caspase 3,Cleaved Caspase 3,Caspase 7 and Caspase 9 in each group.Results: The cell viability of Hcy group was significantly lower than that of Control group.The optimal damage concentration of Hcy and the optimal administration concentration of TXL were determined by MTS method.Compared with Control group,the expression of GRP78,Caspase3,Cleaved Caspase 3,Caspase 7 and Caspase 9 protein in Hcy group was up-regulated,while the expression of apoptotic protein in TXL group was lower than that in Hcy group.Conclusion: Tongxinluo can ameliorate HUVEC damage induced by Hcy and exert its cytoprotective effect through anti-apoptotic pathway.