蜂胶醇提物通过抑制C/EBP同源蛋白表达减轻氧化低密度脂蛋白诱导的血管内皮细胞凋亡  

Ethanol extract of propolis protects vascular endothelial cells from oxidized low-density lipoprotein-induced apoptosis by inhibiting C/EBP homologous protein expression

作　　者：徐晓燕[1] 邵夏炎[2] 刘映雪[2] 李东轩 焦鹏[4] 郝奇[3] 田华[4] 姚树桐[3] 

机构地区：[1]泰山医学院药学院,山东泰安271000 [2]泰山医学院人口与计划生育学院,山东泰安271000 [3]泰山医学院基础医学院,山东泰安271000 [4]泰山医学院动脉粥样硬化研究所,山东泰安271000

出　　处：《中国病理生理杂志》2017年第9期1551-1557,共7页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.81570410;No.81202949);泰山医学院国家级大学生创新训练项目(No.201510439100;No.201510439126);山东省高等学校科技计划(No.J14LM52)

摘　　要：目的:研究蜂胶醇提物(ethanol extract of propolis,EEP)对氧化低密度脂蛋白(oxidized low-density lipoprotein,ox-LDL)诱导的血管内皮细胞凋亡的抑制作用,并探讨可能的分子机制。方法:体外培养人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs),给予EEP(7.5、15和30 mg/L)、4-苯丁酸(4-phenylbutyric acid,PBA;4 mmol/L)预处理1 h,再加入ox-LDL(100 mg/L)或衣霉素(tunicamycin,TM;4 mg/L)继续培养24 h。分别采用MTT法和Annexin V-FITC/PI双染法检测细胞活力和凋亡情况;试剂盒测定培养液乳酸脱氢酶(lactic dehydrogenase,LDH)和细胞内caspase-3活性。分别采用Western blot和real-time PCR技术检测内质网应激(endoplasmic reticulum stress,ERS)凋亡途径关键蛋白C/EBP同源蛋白(C/EBP homologous protein,CHOP)和Bcl-2的表达变化。结果:与ERS抑制剂PBA相似,EEP呈剂量依赖性地减轻ox-LDL所诱导的HUVECs损伤,表现为细胞活力增加(P<0.01或P<0.05),LDH漏出、凋亡率和caspase-3活性降低(P<0.05或P<0.01),且可抑制ERS诱导剂TM所致的HUVECs活力下降(P<0.05),以及LDH漏出、细胞凋亡率和caspase-3活性增加(P<0.05或P<0.01);与PBA相似,EEP可抑制ox-LDL所诱导的CHOP上调和Bcl-2下调(P<0.05或P<0.01);另外,与TM组比较,EEP预处理组CHOP蛋白和mRNA表达上调也受到明显抑制(P<0.05或P<0.01)。结论:EEP可减轻oxLDL所诱导的HUVECs凋亡,其机制可能与抑制CHOP介导的ERS凋亡途径有关。AIM： To investigate the inhibitory effect of ethanol extract of propolis（EEP） on oxidized low-density lipoprotein（ ox-LDL）-induced vascular endothelial cell apoptosis and the underlying molecular mechanisms. METHODS： Human umbilical vein endothelial cells（ HUVECs） were pretreated with EEP（7. 5,15 and 30 mg/L） or 4-phenylbutyric acid（ PBA,4 mmol/L） for 1 h and then treated with ox-LDL（100 mg/L） or tunicamycin（ TM,4 mg/L） for 24 h. The cell viability and apoptosis were determined by MTT assay and Annexin V-FITC/PI double staining,respectively.The activities of lactic dehydrogenase（ LDH） in the medium and caspase-3 in the HUVECs were measured. The protein and mRNA levels of C/EBP homologous protein（ CHOP）,a proapoptotic molecule under endoplasmic reticulum stress（ERS）,and its downstream Bcl-2 were examined by Western blot and real-time PCR,respectively. RESULTS： Like PBA（an ERS inhibitor）,EEP protected HUVECs from ox-LDL-induced injury in a dose-dependent manner,as assessed by the increased cell viability and the decreased LDH release,apoptotic rate and caspase-3 activation. The decrease in cell viability and the increases in LDH release,apoptotic rate and caspase-3 activation induced by TM,an ERS inducer,were also attenuated by EEP. Moreover,EEP suppressed ox-LDL-induced CHOP upregulation and Bcl-2 downregulation,and this effect was similar to that of PBA. Similarly,EEP significantly suppressed TM-induced CHOP upregulation both at the protein and mRNA levels. CONCLUSION： EEP may protect HUVECs from ox-LDL-induced apoptosis,and the mechanism is at least partially involved in suppressing CHOP-mediated ERS-associated apoptotic pathway.

关 键 词：蜂胶醇提物 C/EBP同源蛋白 氧化低密度脂蛋白 血管内皮细胞 细胞凋亡 

分 类 号：R285.5[医药卫生—中药学]