Downregulation of miR-138-5p alleviates propofol-induced neurotoxicity and autophagy by regulating SIRT1

BackgroundPropofol, a commonly utilized anesthetic, has been shown to induce neurotoxicity in developing neurons. A previous study showed that microRNA (miR)-138-5p was dysregulated in hippocampus tissue of mice administrated with propofol. The current study aimed to investigate the functions of miR-138-5p and its target gene in propofol-induced neurotoxicity.MethodsSH-SY5Y neuronal cells were treated with increasing doses of propofol for indicated time to identify the optimal concentration and treatment time. MiR-138-5p and SIRT1 expression in SH-SY5Y neuronal cells stimulated with propofol were measured by RT-qPCR. Western blotting was performed to quantify protein levels of SIRT1 and autophagy markers. After interference of miR-138-5p and/or SIRT1 expression, the toxicity of SH-SY5Y neuronal cells was evaluated by cell counting kit-8 (CCK-8) assays and flow cytometry. The formation of autophagosomes was estimated by monodansylcadaverine staining.ResultsPropofol induced neurotoxicity in a dose- or time-dependent manner. Propofol upregulated miR-138-5p while downregulating SIRT1 in SH-SY5Y neuronal cells. The propofol-stimulated neurotoxicity and autophagy was inhibited by miR-138-5p knockdown. Moreover, miR-138-5p bound to SIRT1 3 ' untranslated region. SIRT1 overexpression increased cell viability while inhibiting apoptosis and autophagy in the context of propofol. SIRT1 downregulation reversed the ameliorative effect of miR-138-5p inhibition on propofol-induced neurotoxicity and autophagy.ConclusionDownregulation of miR-138-5p alleviates propofol-induced neurotoxicity and autophagy via upregulation of SIRT1.