Retinoic Acid Attenuates Cell Death and Reduces Tyrosine Hydroxylase Expression in Ethanol-Treated Human SH-SY5Y Neuroblastoma Cells

Abstract

Background: Retinoic acid (RA) plays an important role in embryonic development and central nervous system function, and has been shown to exert anti-apoptotic effects in various cells. In contrast, ethanol probably exerts its toxicity via pro-apoptotic effects. Here, we investigated the effects of all-trans RA on ethanol-induced cell death in human dopaminergic SH-SY5Y neuroblastoma cells. Methods: Cell viability of SH-SY5Y cells exposed to 25, 50, 100, and 200 mM ethanol for 72 hours, with or without 10 µ M RA, was measured using an MTT assay. Expression of p53, Bcl, and Bax mRNA levels in untreated SH-SY5Y cells and cells exposed to 200 mM ethanol, 10 µ M RA, or both for 24 hours was analyzed using quantitative real-time RT-PCR. Tyrosine hydroxylase (TH) of SH-SY5Y cells exposed to 25, 50, 100, and 200 mM ethanol for 72 hours, with or without 10 µ M RA, was measured using western blotting analysis. Results: The effect of ethanol on cell viability was dose-dependent, and was accompanied by the significant reduction of p53 and Bax mRNA expression, including Bax/Bcl-2 ratio. Western blotting analysis showed that 72 hours of treatment with 200 mM ethanol significantly increased TH expression, but the expression was significantly decreased when cells were co-cultured with 10 µ M RA and 200 mM ethanol. Conclusions: All-trans RA could protect against apoptosis via a p53-dependent pathway and reduce the biochemical adaptation of ethanol-treated SH-SY5Y cells. doi: http://dx.doi.org/10.4021/jnr147w