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bioRxiv · 10.64898/2026.10.22.760251

Ascorbic Acid (Vitamin C) Attenuates Dichlorvos-Induced Neurobehavioral and Oxido-Inflammatory Stress in Discrete Brain Regions

Ogbuokiri, D. K.·Abugu, J. I.·Oladosu, O. B.·Unekwuojo, I. B.·Agufusi, N. P.·Kenechukwu, E. V.
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Abstract

Background: Dichlorvos is a widely used organophosphate pesticide associated with neurotoxicity through acetylcholinesterase inhibition, oxidative stress, and neuroinflammation. Chronic exposure may cause neuronal dysfunction and structural brain alterations. Ascorbic acid (vitamin C), a potent antioxidant, may provide neuroprotection against oxidative damage. This study evaluated the protective effects of ascorbic acid against dichlorvos--induced neurobehavioral and oxido--inflammatory alterations in adult male Wistar rats. Methods: Thirty--six rats were randomly assigned into six groups (n = 6): control, dichlorvos (20 mg/kg), dichlorvos plus low--dose ascorbic acid (50 mg/kg), low--dose ascorbic acid, dichlorvos plus high-dose ascorbic acid (150 mg/kg), and high--dose ascorbic acid groups. Treatments were administered orally for six weeks. Neurobehavioral performance was assessed using the T--maze and hanging--wire tests. Oxidative stress biomarkers, including malondialdehyde, superoxide dismutase, and catalase, were evaluated in the hippocampus and amygdala. Histological examinations of the hippocampus, cerebellum, and prefrontal cortex were also performed. Data were analyzed using one-way ANOVA with Tukey's post hoc test (). Results: No significant difference in brain weight was observed across groups. Neurobehavioral assessments showed no statistically significant differences between pre-- and post--treatment performances, although dichlorvos exposure produced a slight decline, while ascorbic acid--treated groups showed dose--dependent improvement. Dichlorvos significantly increased malondialdehyde levels and decreased superoxide dismutase and catalase activities compared with control (p < 0.05). Co--administration of ascorbic acid significantly reduced lipid peroxidation and improved antioxidant enzyme activities relative to the dichlorvos group (p <0.05). Histologically, the hippocampus remained largely preserved, while mild neuronal degeneration was observed in the prefrontal cortex of dichlorvos--treated rats. The cerebellum showed mostly normal architecture, with mild molecular layer degeneration in the high--dose dichlorvos plus ascorbic acid group. Conclusions: Ascorbic acid attenuated dichlorvos--induced oxidative stress and reduced associated histopathological alterations, with limited but observable improvements in neurobehavioral outcomes. These findings suggest its potential protective role against organophosphate--induced neurotoxicity. Keywords: Ascorbic acid, dichlorvos, oxidative stress, neuroprotection, hippocampus, cerebellum,

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Ogbuokiri, D. K., Abugu, J. I., Oladosu, O. B., Unekwuojo, I. B., Agufusi, N. P., Kenechukwu, E. V.. 2026-10-24. Ascorbic Acid (Vitamin C) Attenuates Dichlorvos-Induced Neurobehavioral and Oxido-Inflammatory Stress in Discrete Brain Regions. https://doi.org/10.64898/2026.10.22.760251

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