Effects of HMGB1 siRNA on the apoptosis of retinal vascular endothelial cells in high glucose environment / 眼科新进展

ABSTRACT

Objective To investigate the effects of HMGB1 small interference RNA (siRNA) on retinal vascular endothelial cells.Methods siRNA was used to inhibit the expression of HMGB1,followed by the application of CCK8 assay,Hochest33342 staining and flow cytometry to observe the effects of HMGB1 siRNA on retinal vascular endothelial cells in high glucose environment.Meanwhile,the expression of proteins related to apoptosis was detected by Western blot.Results The transfection of HMGB1 siRNA down-regulated the protein expression level of HMGB1 by 73％ in siRNA group compared with normal control (NC) group (P ＜ 0.05),and the protein expression level of HMGB1 in siRNA group was decreased by 75％ compared with scr-siRNA group (P ＜ 0.05).There was no significant difference between NC group and scrsiRNA group (P ＞ 0.05).The total apoptotic rate of NC group,high-glucose group,scrsiRNA group and siRNA group was (0.40 ± 0.03)％,(49.80 ± 3.50)％,(47.60 ±1.98) ％ and (23.60 ± 2.40) ％ by flow cytometry.Compared with NC group,the apoptotic rates of high-glucose group,scr-siRNA group and siRNA group were increased (all P ＜ 0.05).Compared with scr-siRNA group,the apoptotic rate of HRECs in siRNA group was reduced,with significant statistical difference (P ＜ 0.05).There was no significant difference in the rate of cell apoptosis between scr-siRNA group and high-glucose group (P ＞ 0.05).Compared with the NC group,the protein expression level of cleavedcaspase3 protein in high-glucose group and scr-siRNA group were increased by (233 ±10) ％ and (266 ± 22) ％,respectively (both P ＜ 0.05);compared with scr-siRNA group,the protein expression level of cleaved-caspase 3 in siRNA group was reduced by (43 ±3) ％ (P ＜ 0.05);and there was no significant difference in the protein expression of cleaved-caspase 3 in high-glucose group and scr-siRNA group (P ＞ 0.05).Compared with the NC group,the protein expression of B-cell lymphoma-2 (Bcl-2) in high-glucose group and scr-siRNA group was decreased by (32 ± 2) ％ and (29 ± 3) ％,accordingly (both P ＜ 0.05);compared with scr-siRNA group,the protein expression level of Bcl-2 in siRNA group was increased by (42 ± 2) ％ (P ＜ 0.05);and there was no significant difference in the protein expression of Bcl-2 in high-glucose group and scr-siRNA group (P ＞ 0.05).Conclusion HMGB1 siRNA can reduce the apoptosis of retinal vascular endothelial cells in high glucose environment by inhibiting the activation of cleavedcaspase3 and increasing the expression of Bcl-2.