【摘要】 目的探讨人脐静脉内皮细胞株(HUVEC)中类表皮生长因子功能域7(EGFL7)对共培养的人主动脉平滑肌细胞(AoSMC)凋亡的影响以及可能的信号转导通路。方法利用细胞共培养池行HUVEC与AoSMC共培养,将EGFL7的特异siRNA转染HUVEC细胞,利用MTS法检测HUVEC中EGFL7基因的有效沉默对共培养的AoSMC细胞存活率的影响;并合成无关siRNA作为阴性对照组(neg组),以未转染siRNA的细胞为空白对照组(con组)。同时利用分光光度法检测其对AoSMC细胞乳酸脱氢酶(LDH)、三磷酸腺苷(ATP)以及细胞凋亡蛋白酶(Caspase-3)表达的影响;应用RT-PCR检测共培养AoSMC的bcl-2及bax mRNA表达水平的改变。结果与neg组及con组相比,干扰HUVEC细胞EGFL7表达12 h后,AoSMC存活率无明显变化(P>0.05),而干扰24、36、48 h后,存活率显著降低(P<0.05);干扰12、24、36、48 h后,AoSMC细胞线粒体ATP释放量减少、培养基中LDH含量及Caspase-3表达量均增加(P<0.05)。RT-PCR检测结果显示,与neg组及con组相比,干扰siRNA转染HUVEC细胞24、36、48 h,共培养的AoSMC凋亡基因bcl-2表达水平轻度降低(P<0.05);但Bax表达水平在相应干预时间点均无明显改变(P>0.05)。结论内皮细胞株EGFL7基因沉默时,可导致平滑肌细胞凋亡;EG-FL7通过bcl-2相关信号通路调节SMC凋亡,而与Bax基因表达无关。更多还原

【Abstract】 Objective To investigate the effect of epidermal growth factor(EGF)-like domain 7(EGFL7) of human umbilical vein endothelial cells(HUVEC) on apoptosis of co-cultured human aortic smooth muscle cells(AoSMC) and its signal transduction pathway.Methods HUVEC and AoSMC were co-cultured in cell co-culture pools.The special siRNA targeting EGFL7 was transfected into HUVEC by lipofectamine,irrelevant siRNA as the negative group(neg) and siRNA-nontransfected cells as the control group(con).When the Egfl7 gene was silenced in HUVEC,AoSMC cell survival rates were determined by MTS,LDH,ATP and Caspase-3 release amount by spectrophotometry,and Bcl-2 and bax expressions in AoSMC by RT-PCR.Results AoSMC survival rates decreased significantly after 24,36 and 48 hours(P <0.05).There were significant differences in the ATP release amount,LDH content in medium and Caspase-3amount at 12,24,36 and 48 hours(P < 0.05).bcl-2 expression was gently reduced and there were significant differ-ences at 24,36 and 48 hours compared with the control and negative group(P < 0.05),while there was no significant difference in bax expression(P > 0.05).Conclusion The silence of EGFL7 in HUVEC could promote apoptosis of AoSMC.EGFL7 may regulate apoptosis of SMC via the Bcl-2-related signal pathway.更多还原