Protective effect of BAG-1L mediated by lentivirus in human neuroblastoma cells induced by hypoxia / 中华危重病急救医学

ABSTRACT

Objective To investigate the protective effects of lentivirus mediated Bcl-2-associated athanogene 1L (BAG-1L) over-expression on human neuroblastoma cells (SH-SYSY) induced by hypoxia/re-oxygenation,and to study its effect on the phosphoinositide 3 kinase serine/threonine protein kinase (PI3K/AKT) pathway.Methods SH-SYSY cells were cultured in vitro,and the cells at logarithmic phase were collected,and they were divided into recombined lentiviral infection group [infected by lentivirus containing BAG-1L and green fluorescent protein (GFP) gene],vector control group (infected by lentivirus containing GFP without BAG-1L gene) and cell control group (non-infection).Western Blot was used to detect the expression of BAG-1L in target cells after infection for 48 hours.SH-SY5Y cells were subjected to hypoxia for 8 hours and re-oxygenation for 24 hours,then the cell counting kit-8(CCK-8) was used to detect the cell activity,and the apoptosis was detected by flow cytometry after allophycocyanin labeled annexin V/7-amino actinomycin D (Annexin V-APC/7-AAD) staining.Western Blot was used to detect the protein expressions of BAG-1L,heat shock protein 70 (HSP70),AKT and phosphorylated AKT (p-AKT).Results After infection for 48 hours,exogenous BAG-1L protein bands were observed in recombined lentiviral infection group,but not observed in cell control group and vector control group.After hypoxia/re-oxygenation treatment,the cell viability in recombined lentiviral infection group was significantly higher than that in cell control group and vector control group (A value0.689 ± 0.036 vs.0.425 ± 0.013,0.400 ± 0.012),apoptosis was significantly decreased [apoptosis rate(26.97 ± 1.82)％ vs.(36.60± 1.45)％,(35.77 ± 3.74)％],the protein levels of BAG-1L,HSP70 and p-AKT were significantly increased [BAG-1L protein (gray value)2.405 ± 0.167 vs.0.529 ± 0.141,0.601 ± 0.099;HSP70protein (gray value)0.997±0.123 vs.0.634±0.091,0.584±0.106;p-AKT protein (gray value)1.234±0.118 vs.0.661 ± 0.210,0.712 ± 0.199,all P ＜ 0.01],but the protein level of AKT was slightly increased (gray value1.103 ± 0.269vs.0.646 ± 0.188,0.791 ± 0.326) without statistically significant differences (both P ＞ 0.05).There was no significant difference in all parameters between cell control group and vector control group (all P ＞ 0.05).Conclusion Lentivirus mediated BAG-1L gene over-expression can protect nerve cells against hypoxic injury and apoptosis,and the protective effect may be related to the activation increase of pathway on PI3K/AKT.