金花茶叶提取物减轻动脉粥样硬化的作用机制

Mechanisms of Camellia chrysantha leaves extract in attenuating atherosclerosis

目的考察金花茶叶提取物减轻动脉粥样硬化的作用机制。方法100μg/mL ox-LDL诱导人脐静脉内皮细胞(HUVEC)趋化THP-1人单核细胞,流式细胞术评估10%金花茶叶提取物含药血清对趋化过程的抑制作用,免疫印迹法检测HUVEC细胞间粘附分子1(ICAM-1)、血管粘附分子1(VCAM-1)、巨噬细胞趋化蛋白1(MCP-1)、P-选择素(P-selectin)蛋白表达。高脂饲喂ApoE基因敲除雄性小鼠建立动脉粥样硬化模型,每天灌胃给予生药量5 g/kg的金花茶叶提取物,共8周,病理切片镜检评估其抑制主动脉弓粥样斑块形成的体内药效,免疫印迹法检测主动脉弓内膜组织ICAM-1、VCAM-1、MCP-1、P-selectin蛋白表达。结果金花茶叶提取物含药血清体外抑制ox-LDL诱导的HUVEC趋化单核细胞,体内减轻动脉粥样硬化小鼠的粥样斑块形成,HUVEC与主动脉弓内膜的ICAM-1、VCAM-1、MCP-1、P-selectin过表达均被抑制。结论金花茶叶提取物可有效抑制ox-LDL诱导的血管内皮细胞趋化单核细胞,减轻动脉粥样斑块形成,其机制可能与下调血管内皮细胞ICAM-1、VCAM-1、MCP-1、P-selectin过表达有关。

AIM To investigate the mechanisms of Camellia chrysantha(Hu)Tuyama leaves extract in attenuating atherosclerosis.METHODS The chemotaxis of human umbilical vein endothelial cells(HUVEC)on THP-1 myocytes was induced by 100μg/mL oxidized low-density lipoprotein(ox-LDL),and the extent of the process inhibited by C.chrysantha leaves extract-containing serum was further evaluated using flow cytometry.The HUVEC had their protein expressions of intercellular adhesion molecule 1(ICAM-1),vascular cell adhesion molecule 1(VCAM-1),macrophage chemotactic protein 1(MCP-1)and P-selectin detected by Western blot.ApoE gene knockout mouse models with atherosclerosis established by high-fat feeding were administered intragastrically with C.chrysantha leaves extract,equivalent to 5 g of the crude drug/kg per day,within 8 weeks.The C.chrysantha leaves extract had its in vivo inhibitory effect on the atherosclerotic plaque formation in aortic arch evaluated using microscopic examination at pathological section,and its impact on protein expressions of ICAM-1,VCAM-1,MCP-1 and P-selectin in aortic arch intima tissue detected by Western blot.RESULTS C.chrysantha leaves extract-containing serum inhibited the chemotaxis of HUVEC on myocytes in vitro;markedly attenuated the atherosclerotic plaque formation in mice with atherosclerosis in vivo;and significantly inhibited the overexpressions of ICAM-1,VCAM-1,MCP-1 and P-selectin in both HUVEC and aortic arch intima tissue.CONCLUSION C.chrysantha leaves extract can effectively inhibit the chemotaxis of HUVEC on ox-LDL-induced myocytes,and prominently attenuate the atherosclerotic plaque formation.These benefits may be related to a down-regulation on the over expressions of ICAM-1,VCAM-1,MCP-1 and P-selectin in vascular endothelial cells.