Influence of simvastatin on dopaminergic neurons of lipopolysaccharide-induced rat model of Parkinson's disease

Objective: To investigate the neuroproLective effects of simvastatin on lipopolysaccharide (LPS)-induced rat model of Parkinson's disease (PD) and the mechanisms involved. Methods: Hemiparkinsonian rat models were induced by stereotaxieal injection of EPS in the right substantia nigra compacta. After 2 weeks of simvastatin treatment, rotational behavior test was performed after the intraperitoneal injection of apomorphinc. Expression of tyroxine hydroxylase (TH) and glial fibrillary acidic protein were analyzed through immunohistochemical staining rd substantia nigra and striatum, and the level of TNF-alpha was evaluated using enzyme-linked immunosorbent assay. Results: Comparing with untreated group, behavioral symptoms of the rats were significantly less in the rats that received simvastatin treatment. The TH positive cell count in substantia nigra and striatum were significantly increased (P<0.05) and TNF-alpha expression was significantly decreased (P<0.05) in simvastatin group compared to untreated group. Conclusions: Simvastatin could effectively inhibit the activation of astrocyles, reduce TNF-alpha expression, and exert anti-inflammatory effects, and thus protect the dopaminergic neurons in substantia nigra and striatum of the rat model of PD.