Introduction: Methamphetamine (MA) induces cell death through several mechanisms. Insulin has an important role in the cell proliferation and apoptosis via GSK3β inactivation. Here, we evaluated the effect of insulin and SB-216763, a selective GSK3β inhibitor, on MA-induced cell death in neuroblastoma SH-SY5Y, and rat primary midbrain cells.
Methods: Human SH-SY5Y and rat primary midbrain cells extracted from E14.5 rat embryo were treated with insulin (0.005-0.15U) or SB-216763 (0.5-9µM) with or without MA (5mM). The cells viability was assessed after 24, 48, and 72 h. The expression of TNFα, Bax, Bim, and Bcl2 was examined in primary midbrain cells after 72 h of treatment with 5mM MA, insulin (0.1U), and SB-216763 (3µM).
Results: MA significantly decreased the viability of human SH-SY5Y and rat primary midbrain cells, and insulin and SB-216763 could increase it. In addition, elevated expression of TNFα and Bax following MA, was attenuated by insulin and SB-216763 in primary midbrain cells.
Conclusion: These findings demonstrated that MA decreases the cell viability of rat primary midbrain cells, at least in part, by upregulation of inflammatory and apoptotic factors and treatment with insulin and SB-216763 could attenuate MA toxicity.