ABSTRACT: Tribulus terrestris (T.T.) is a rich source of flavonoids and saponins, which have been reported to have neuroprotective and antioxidant potential. The current study was planned to investigate the anti-Parkinson's activity of T. terrestris methanol extract (TTME). It was hypothesized that TTME possessed antioxidant potential and can ameliorate Parkinson's disease (PD) via modulation of ?-synuclein, acetylcholinesterase (AChE), TNF-?, and IL-1?. To test this hypothesis, in silico and in vivo studies were performed. The PD model in rats was prepared by giving haloperidol, 1 mg/kg, i.p. Rats were divided into six groups: control, disease control, standard, and treatment groups receiving TTME orally at 100, 300, and 1000 mg/kg dose levels for 21 days. Behavioral observations and biochemical analyses were done. The TTME modulatory effect on mRNA expression of ?-synuclein, AChE, TNF-?, and interleukins in the brain homogenate was estimated by RT-PCR. Compounds detected in HPLC analysis disrupted the catalytic triad of AChE in in silico studies. Behavioral observations showed significant (p < 0.05) improvement in a reversal of catatonia, muscular strength, locomotor functions, stride length, and exploration in a dose-dependent manner (1000 >300 >100 mg/kg) of PD rats. Endogenous antioxidant enzyme levels CAT, SOD, GSH, and GPx were significantly restored at a high dose (p < 0.05) with a notable (p < 0.05) decrease in the MDA level in TTME-treated groups. TTME at a high dose significantly (p < 0.05) decreased the level of acetylcholinesterase. RT-PCR results are showing down-regulation in the mRNA expression levels of IL-1?, ? -synuclein, TNF-?, and AChE in TTME-treated groups compared to the disease control group, indicating neuroprotection. It is concluded that TTME has potential to ameliorate the symptoms of Parkinson's disease.
