The Effect of Carica Papaya Leaves Extracts on the Histology and the Markers of Haloperidol-Induced Parkinsonism in the Brain of Wistar Rats,

Abstract Parkinson’s disease (PD) is a progressive neurodegenerative disorder marked by the loss of dopaminergic neurons in the substantia nigra, leading to motor and cognitive impairments. Haloperidol, a dopamine D2 receptor antagonist, is commonly used to model Parkinsonism in experimental studies due to its ability to induce oxidative stress and neuronal degeneration similar to PD. This study evaluated the neuroprotective potential of Carica papaya leaf extract on the brain histology and biochemical markers of haloperidol-induced Parkinsonism in Wistar rats. Twenty-five adult male rats were randomly divided into five groups, including control, haloperidol-treated, and varying doses of Carica papaya extract, with or without haloperidol co-administration. Histological examinations were conducted on brain tissues using hematoxylin and eosin staining to assess structural integrity, while biochemical assays measured oxidative stress markers such as malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH). Results showed that haloperidol administration caused notable neuronal degeneration and elevated oxidative stress levels. However, rats treated with Carica papaya extract exhibited improved neuronal morphology, reduced lipid peroxidation, and enhanced antioxidant enzyme activity, indicating its potential to protect against haloperidol-induced neurotoxicity. The findings suggest that Carica papaya leaves possess significant antioxidant and neuroprotective properties, making them a promising natural therapeutic candidate for managing Parkinsonism and related neurodegenerative conditions.