Involvement Of PUMA In Methamphetamine-mediated Microglia Apoptosis

Objective:To investigate the effect and mechanism of methamphetamine (Meth) through PUMA on the microglia apoptosis, and provide potential therapeutic targets for the treatment of addictive drugs.Materials and methods:MTT and NO assay kit were used to assess the cell viability and Nitric oxide (NO) level as well as the pretreatment with NOS inhibitor L-NAME. Western Blot was taken for the analyses of iNOS expression. RT-PCR、real-time PCR、Western Blot and IF staining were taken for the expression of PUMA. siRNA PUMA was taken for the effect on BV2 cells. IF staining、Western Blot、Hoechst 33342 staining were taken for the expression of a-1R. The levels of MAPKs、PI3K-Akt、p53、Bax/Bcl-xL、Caspase 9 and Caspase 3 were detected by Western Blot.Results:1) Meth promoted BV2 cells activation-induced cell death(AICD); 2) Meth mediated up-regulation of PUMA mRNA and protein in BV2 cells; 3) siRNA PUMA inhibited BV2 cells apoptosis; 4) Meth mediated expression of PUMA involves a-1R activation; 5) Meth mediated activation of MAPKs、PI3K-Akt、p53、Bax/Bcl-xL、Caspase 9 and Caspase 3 pathways.Conclusion:The up-regulation of PUMA induced by Meth in microglia through its binding to σ-1R, via the activation of MAPKs and PI3K-Akt pathway and p53 nuclear translocation, up-regulated the ratio of Bax/Bcl-xL and expression of Caspase 9 and Caspase 3 proteins, and eventually cause apoptosis of microglia, PUMA may become a new target of Meth induced nerve injury.