烟酸姜黄素酯对低剪切应力诱导人脐静脉内皮细胞凋亡的影响及相关机制

Effects and mechanisms of nicotinic acid curcumin on apoptosis induced by low shear stress in human umbilical vein endothelial cells

目的:探讨烟酸姜黄素酯(curcumin nicotinate,CN)对低剪切应力(low shear stress,LSS)诱导人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)凋亡的影响及机制研究。方法:运用平行平板流动腔建立LSS诱导的HUVECs凋亡模型。采用Hoechst33258荧光染色,流式细胞术检测CN对LSS诱导的HUVECs凋亡的影响。Western blot检测CN对LSS诱导的HUVECs中前蛋白转化酶枯草溶菌素9(proprotein convertase subtilisin/kexin type 9,PCSK9)蛋白表达的影响。结果:Hoechst33258荧光染色结果显示,与静态培养组比较,LSS组(3 dyne/cm2,12 h)内呈现凋亡状态的HUVECs明显增多。与LSS组比较,各CN+LSS组内呈现凋亡状态的HUVECs明显减少,并且呈现浓度依赖性。其中以20μmol/L CN+LSS组凋亡细胞数最少;流式细胞术结果显示,与静态培养组比较,LSS组HUVECs凋亡率明显增加,差异有显著统计学意义(P<0.01);与LSS组比较,各CN+LSS组HUVECs凋亡率明显减少,并且呈现浓度依赖性,其中以20μmol/L CN+LSS组HUVECs凋亡率减少最为明显,差异具有显著统计学意义(P<0.01)。Western blot结果显示与静态培养组比较,LSS组内PCSK9蛋白表达显著升高,差异具有统计学意义(P<0.01);与LSS组比较,CN+LSS组内PCSK9蛋白表达下降,并且呈现浓度依赖性,差异具有统计学意义(P<0.05)。其中以20μmol/L CN+LSS组PCSK9蛋白表达下降最为明显(P<0.01)。结论:CN能够抑制LSS诱导的HUVECs凋亡,其作用机制与CN下调LSS处理的HUVECs中PCSK9蛋白表达相关。

AIM： To investigate the effect of curcumin nicotinate（CN） on apoptosis of human umbilical vein endothelial cells（HUVECs） induced by low shear stress（LSS） and its mechanism. METHODS： A parallel plate flow chamber was used to establish a model of HUVECs apoptosis induced by low shear stress. Hoechst33258 fluorescence staining and flow cytometry were used to detect the effects of curcumin on the apoptosis of HUVECs. Western blot was used to detect the expression of proprotein convertase subtilisin/kexin type 9. RESULTS： Hoechst33258 fluorescence staining showed that the number of HUVECs with apoptotic status in the LSS group was significantly higher than that in the static culture group. Compared with the LSS group,the HUVECs showing apoptotic status in the CN ＋ LSS group were significantly reduced and showed a concentration-dependent manner. Among them,the least number of apoptotic cells was in 20 μmol/L CN ＋ LSS group.Flow cytometry results showed that compared with the static culture group,the apoptosis rate of the LSS group was significantly increased, and the difference was statistically significant（P〈0.01）;compared with LSS group,the apoptosis rate of HUVECs in CN ＋ LSS group was significantly reduced and showed a concentration-dependent manner. Among them,the decrease of apoptotic rate with 20μmol/L CN ＋ LSS group was the most obvious,the difference was statistically significant（P〈0.01）.Western blot results showed that compared with static culture group,PCSK9 protein expression was significantly increased in LSS group,and the difference was statistically significant（P〈0.01）. Compared with the LSS group,the expression of PCSK9 protein in the CN ＋ LSS group was decreased and showed a concentration-dependent manner. The difference was statistically significant（P〈0.05）. Among them,the expression of PCSK9 protein was significantly decreased in 20 μmol/L CN ＋ LSS group（P〈0.01）.CONCLUSION： CN inhibits the apoptosis of HUVECs induced by LSS,and its mechanism is related to down-regulation of the protein expression of PCSK9 in HUVECs under the action of LSS.