Effects of Bcl-2 associated with athanogene-1 gene silencing on heat shock protein 70 expression and human neuroblastoma cell apoptosis induced by hypoxia / 中国中西医结合急救杂志

ABSTRACT

Objective To investigate the protective effects of Bcl-2 associated with athanogene-1 (BAG-1) gene on human neuroblastoma cells (SH-SY5Y) injury induced by hypoxia/reoxygenation,and its influence on heat shock protein 70 (HSP70) expression.Methods The SH-SYSY cells at logarithmic growth phase were collected.Lenti virus mediated RNA interference (RNAi) technology was used to suppress the BAG-1 expression.The cells screened out can be divided into four groups:the cell control group with no lentivirus infection,lentivirus control group (containing only fluorescein protein lentivirus infection),BAG-1 siRNA group (BAG-1 siRNA silencing group),including BAG-1 siRNA-α group and BAG-1 siRNA-β group with lentivirus containing fluorescein protein (GFP) but at different BAG-1 siRNA target sites of silencing.Western Blot was used to detect the protein expression of BAG-1 and HSP70 in target cells after infectious recombination lentivirus for 72 hours;the Cell Counting Kit-8 (CCK-8) was used to detect the activity of four different group cells after hypoxia;the flow cytometry was used to detect the cell apoptosis;the HSP70 mRNA transcription level were detected by real-time fluorescent quantitative reverse transcription-polymerase chain reaction (RT-qPCR) respectively in each group.Results After lentiviral infection for 72 hours,the Western Blot results showed that in the two BAG-1 siRNA silencing groups,the interference effect of BAG-1 siRNA-β group was superior to that of BAG-1 siRNA-α group.The cell viability of each group showed an increase followed by a decrease with the prolongation of hypoxia time,and reaching the peak at 8 hours.After hypoxia for 8 hours being given,the cell viability in BAG-1 siRNA-β group was significantly lower than that of the cell control group,lentivirus control group and BAG-1 siRNA-α group (A value:0.59 ±0.09 vs.0.94±0.12,0.90± 0.11,0.91± 0.14,P ＜ 0.01);the cell apoptosis rate was obviously higher in BAG-1 siRNA-β than that in the above three groups [(34.63 ± 3.46)％ vs.(14.83 ± 3.75)％,(19.93 ± 6.49)％,(16.40± 1.18)％,all P ＜ 0.01].There were no statistically significant differences in the HSP70 protein level and mRNA transcription level between BAG-1 siRNA-3 grroup,and the cell control group,lentivirus control group and BAG-1 siRNA-α group respectively (all P ＞ 0.05).Conclusion BAG-1 gene can play a role in protection of hypoxia nerve cells,reduce the apoptosis,and its protective effect can be independent of HSP70 gene.