Abstract:

The human nervous system is highly susceptible to various environmental toxins, which can lead to neurodegenerative conditions characterized by cognitive deficits, motor dysfunction, and even cell death. Among these toxins, lead (Pb) and Monosodium Glutamate (MSG) have been evaluated in this study for their neurotoxic effects. Lead exposure has been associated with detrimental effects on the central nervous system, similarly, MSG, a common food additive, has been reported to induce neurotoxicity through oxidative stress and excitotoxicity mechanisms. Eugenol, found in essential oils, have demonstrated promising antioxidant, anti-inflammatory and neuroprotective properties. Hence Eugenol was used as a therapeutic agent against lead acetate and MSG induced neurotoxicity by modulating Brain-derived Neurotrophic Factor. This in vivo study involved 48 Wistar albino rats, divided into eight groups consisting of Control, Lead acetate induction (100 mg/kg b.wt for 30 days), MSG induction (2 g/kg b.wt for 21 days) and subsequent treatment with Eugenol (250 mg/kg b.wt for 30 days) in comparison with positive control, memantine (20mg/kg b.wt for 15 days). Histopathological and BDNF gene expression were evaluated after the experimental period. Histopathological analysis confirmed that eugenol preserved neuronal integrity, reducing neuronal damage caused by lead acetate and MSG exposure by modulating free radical generation upon oxidative stress. Eugenol treatment in rats exposed to lead and MSG resulted in a significant upregulation of BDNF expression (p<0.01) compared to the untreated toxin-exposed groups. These outcomes suggest that Eugenol could be a possible therapeutic agent for protecting the neuronal tissues from Lead acetate and MSG-induced neurotoxicity.

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