LAUSR

INTRODUCTION Mephedrone, a synthetic derivative of cathinone, is a commonly used psychoactive substance. Exposure to mephedrone during pregnancy induced antiproliferative and proapoptotic effects in hippocampous of mice delivered pups. The aim of present study is to investigate the effects of mephedrone exposure on the proliferation, differentiation, and apoptosis of rat embryonic NS/PC. METHODS NS/PC was isolated from rat fetal ganglionic eminence region at embryonic day 14.5. The effects of mephedrone on cell proliferation, neurosphere formation (colonies of NS/PC), neuronal differentiation, and apoptosis of NS/PC were assessed using MTT, immunocytochemistry, and flow cytometry. RESULTS Mephedrone at concentrations of (20-640 μM) significantly decreased the proliferation of NS/PC and induced cell cycle arrest. Neurosphere assays revealed a significant reduction in the number and diameter of neurosphere-forming cells. In addition, mephedrone significantly decreased expressions of DCX and NeuN neuronal markers. CONCLUSION Taken together, our results suggests that exposure to mephedrone induced cell death in NS/PC via apoptosis or necrosis. Mephedrone decreased the proliferation and neuronal differentiation of embryonic NS/PC. The study implied that mephedrone exposure during fetal or neonatal life may impair neurogenesis and subsequent brain development.