Paliperidone Protects SH-SY5Y Cells Against MK-801-Induced Neuronal Damage Through Inhibition of Ca(2+) Influx and Regulation of SIRT1/miR-134 Signal Pathway.

Schizophrenia is a serious psychotic disease. Recently, increasing evidences support that neurodegeneration occurs in the brain of schizophrenia patients with progressive morphological changes. Paliperidone, an atypical antipsychotic drug, could attenuate psychotic symptom and protect neurons from different stressors. However, the underlying mechanisms are largely unknown. In this study, we used SH-SY5Y cells to evaluate the neuroprotective capability of paliperidone against the neurotoxicity induced by N-methyl-D-aspartate receptor antagonist, MK-801. And, we also explored the possible molecular mechanism. Neurotoxicity of 100 μM MK-801, which reduced the cell viability, was diminished by 100 μM paliperidone using MTT and LDH assays (both p < 0.05). Analysis with Hoechst 33342/PI double staining demonstrated that exposure to MK-801 (100 μM) for 24 h led to the death of 30 % of cultured cells (p < 0.05). Moreover, the patch clamp technique was employed to detect voltage calcium channel changes; the results showed that paliperidone effectively blocked the Ca(2+) influx through inhibiting the voltage-gated calcium channels (p < 0.05). Furthermore, paliperidone significantly reversed MK-801 induced increase of SIRT1 and decrease of miR-134 expression (both p < 0.05). Finally, SIRT1 inhibitor nicotinamide blocked MK-801 injury effects and suppressed miR-134 expression. Taken together, our results demonstrated that paliperidone could protect SH-SY5Y cells against MK-801 induced neurotoxicity via inhibition of Ca(2+) influx and regulation of SIRT1/miR-134 pathway, providing a promising and potential therapeutic target for schizophrenia.