Neuroprotective effect of methanolic extract of Sargassum wightii on rotenone-induced parkinsonism-like symptoms in Wistar albino rats

Introduction: The pathogenesis of Parkinson’s disease (PD) is multifactorial in which oxidative stress, neuroinflammation, and mitochondrial dysfunction are the leading factors. Currently, the antioxidant and anti-inflammatory agents of natural sources as neuroprotectants have raised much attention. The current study aimed to explore the neuroprotective effect of methanolic extract of Sargassum wightii in male Wistar albino rats against rotenone-induced PD. Methods: The rats were administered with rotenone (۱۰ mg/kg orally) daily for ۲۸ days to induce PD. S. wightii (۲۰۰ mg/kg and ۴۰۰ mg/kg) and levodopa+carbidopa combination (۱۰ mg/kg) were administered to different groups of rats one hour prior to rotenone for ۲۸ days. Behavioral parameters (akinesia, tremor, motor coordination, and locomotor activities) and body weight were recorded on days ۱۴th and ۲۸th of drug treatment. On the ۲۸th day, the animals were sacrificed for the neurobiochemical analyses of brain tissue. Results: Rotenone treatment caused a significant reduction in behavioural parameters (P < ۰.۰۰۱), neurochemical deficits (P < ۰.۰۰۱), and elevation of oxidative stress markers (P < ۰.۰۰۱) in the brain. Pre-treatment with S. wightii at ۲۰۰ mg/kg and ۴۰۰ mg/kg doses significantly attenuated the rotenone-induced behavioral alterations and restored the mitochondrial NADH dehydrogenase activity and dopamine level in the striatum (P < ۰.۰۰۱). Moreover, ۴۰۰ mg/kg of S. wightii restored the rotenone-induced increased oxidative stress markers like malondialdehyde (MDA), superoxide dismutase (SOD), and reduced glutathione (GSH) in the striatum (P < ۰.۰۱). Conclusion: S. wightii has provided a neuroprotective effect, probably by virtue of its antioxidant and dopamine restoring potential. Hence, it may offer a promising and new therapeutic lead for the treatment of PD but needs further research.