RÉSUMÉ
Background: Parkinson’s disease (PD) is typically characterised by motor shortfalls. However, non-motor symptoms like mood disorders (anxiety, depression) and impaired cognition are also associated features. Previous studies have demonstrated a neuroprotective effect a plant against a disease. Consequently, this current study was focused on assessing its efficacy in extenuating non-motor shortfalls such as anxiety-like behaviour and impaired cognition induced by rotenone. Methods: PD was induced in rats by administering rotenone (10 mg/kg BW orally) for 28 days. The vehicle and the test drug were given orally daily for one hour prior to rotenone administration. The protective effect of methanol extract of A. viridis (500 mg/kg BW) was assessed through an array of tests; elevated plus maze test, Morris water maze test, and novel object recognition test. The rats were sacrificed on day 28th and neurobiochemical analyses of the hippocampus were performed using HPLC. Results: The findings of this study showed that co-administration of A. viridis reversed the rotenone-induced anxiety-like behaviour and cognitive shortfalls to a significant extent (p<0.001). It also restored the hippocampal neurotransmitters [(5-hydroxytryptamine (5-HT), 5-hydroxy indole acetic acid (5-HIAA), and dopamine (Da)] significantly (p<0.001). Conclusions: Amaranthus viridis offered neuroprotective effects that ameliorate non-motor symptoms in PD. This could be a novel insight into the therapy of PD. This study provides scientific evidence that A. viridis attenuates non-motor symptoms like anxiety-like behaviour and cognitive deficits in Parkinsonism. This extract can be a potential candidate in herbal formulations as a neuroprotectant against PD.