Bad在地塞米松抑制嘌呤霉素诱导足细胞凋亡中的表达及意义

Significance and Expression of Bad in Dexamethasone Inhibited Apoptosis of Podocytes Induced by Puromycin Aminonucleoside in vitro

目的观察嘌呤霉素(PAN)诱导和地塞米松(DEX)干预后足细胞凋亡率及凋亡相关蛋白Bad表达的变化。方法体外培养小鼠足细胞,将其分为对照组、PAN组和DEX组。对照组用含二甲基亚砜的RPM I-1640培养液培养;PAN组加入PAN;DEX组同时加入PAN和DEX。处理8 h、24 h和48 h后,用实时荧光定量聚合酶链式反应及W estern blot分别检测各时间点Bad mRNA和蛋白的表达;用Annexin V-FITC/PI双染色法结合流式细胞仪检测足细胞凋亡率的变化。结果 1.PAN组各时间点Bad mRNA的表达均较对照组升高,并呈上升趋势,24 h和48 h时均显著升高(Pa<0.01);8 h时Bad蛋白表达与对照组比较无明显差异(P>0.05),24 h和48 h时均较对照组明显升高(Pa<0.05);各时间点足细胞凋亡率均较对照组升高,48 h时显著升高(P<0.01)。2.DEX组Bad mRNA和蛋白的表达8 h时与PAN组比较无明显差异,但24 h时明显降低(P<0.05),各时间点足细胞凋亡率均较PAN组降低,24 h时显著降低(P<0.01)。结论 PAN诱导足细胞后其凋亡率明显升高,可能与Bad mRNA及蛋白的表达增高有关,而DEX可能通过降低Bad mRNA及蛋白的表达减少足细胞的凋亡而抑制PAN的诱导,起到保护足细胞的作用。

Objective To observe the changes of the expression of Bad and the apoptosis ratio in podocytes induced by puromycin ami-nonucleoside（PAN） and intervened by dexamethasone（DEX） in vitro.Methods Mouse podocytes in control group were cultured with RPMI-1640 plus dimethyl sulphoxide,and were subjected to PAN treatment alone（PAN group） or with DEX（DEX group） for 8 h,24 h,48 h,respectively.The mRNA and protein expressions of Bad were detected with real time fluorescent quantitative polymerase chain reaction and Western blot.The apoptosis ratio of podocytes was determined by Annexin V-FITC/PI double staining combined with flow cytometry.Results 1.The mRNA expression of Bad increased in a dependent time manner in PAN group compared with control group and significantly increased at 24 h and 48 h（Pa0.01）.There was no significant difference of Bad protein expression between PAN group and control group at 8 h（P0.05）,but it obviously increased at 24 h and 48 h in PAN group（Pa0.05）.The apoptosis ratio of podocytes also increased in PAN group at each time point and significantly increased at 48 h（P0.01）.2.Though there was no significant difference of Bad protein and mRNA expression between DEX group and PAN group at 8 h,but both obviously decreased in DEX group at 24 h compared with PAN group（P0.05）.The apoptosis ratio of podocytes also decreased in DEX group compared with PAN group and significantly decreased at 24 h（P0.01）.Conclusions The apoptosis ratio of podocytes obviously increases after getting induced by PAN,which may be related to the increase of the mRNA and protein expressions of Bad,and DEX may reduce the apoptosis ratio of podocytes by reducing the mRNA and protein expressions of Bad,inhibiting induction of PAN,thereby protect podocytes.