CUCURBITA PEPO SEED OIL PREVENTS METHOTREXATE-INDUCED ACETYLCHOLINESTERASE INHIBITION AND POSSIBLE GLUTAMATE NEUROTOXICITY IN FEMALE WISTAR RATS

ABSTRACT Methotrexate (MTX) is a widely used chemotherapeutic and immunosuppressive drug in the treatment of malignancies, autoimmune diseases, and inflammatory disorders. Despite its clinical effectiveness, methotrexate has been associated with several adverse neurological effects including oxidative stress, neuronal degeneration, disruption of neurotransmitter metabolism, and cognitive impairment. One of the major biochemical alterations induced by methotrexate is the inhibition of acetylcholinesterase (AChE), an enzyme responsible for the breakdown of acetylcholine in the nervous system. Suppression of AChE activity may lead to abnormal cholinergic transmission, neuronal overstimulation, and neurotoxicity. In addition, methotrexate administration has been implicated in increased glutamate levels within neural tissues, resulting in excitotoxicity and neuronal damage. Cucurbita pepo (pumpkin) seed oil is a natural plant-derived oil rich in antioxidants, essential fatty acids, phytosterols, tocopherols, and phenolic compounds. Previous studies have demonstrated that Cucurbita pepo seed oil possesses anti-inflammatory, antioxidant, neuroprotective, and cytoprotective properties. These bioactive constituents may play an important role in protecting neuronal cells against chemically induced neurotoxicity. This study investigated the protective effect of Cucurbita pepo seed oil against methotrexate-induced acetylcholinesterase inhibition and glutamate-mediated neurotoxicity in female Wistar rats. Twenty-four healthy female Wistar rats weighing between 150–200 g were randomly divided into four experimental groups. Group I served as the normal control and received distilled water. Group II received methotrexate to induce neurotoxicity. Group III received Cucurbita pepo seed oil prior to methotrexate administration, while Group IV received Cucurbita pepo seed oil alone. Following the treatment period, brain tissues were harvested and analyzed for acetylcholinesterase activity and glutamate levels using standard biochemical methods. The results revealed that methotrexate significantly decreased acetylcholinesterase activity and increased glutamate concentration in brain tissues compared to the control group. However, pre-treatment with Cucurbita pepo seed oil significantly restored acetylcholinesterase activity and reduced glutamate levels towards normal values. The findings of this study suggest that Cucurbita pepo seed oil possesses neuroprotective potential and may mitigate methotrexate-induced neurotoxicity by modulating cholinergic function and preventing glutamate excitotoxicity. These protective effects are likely associated with the antioxidant and anti-inflammatory properties of the seed oil. Therefore, Cucurbita pepo seed oil may represent a promising natural therapeutic agent for preventing drug-induced neurotoxicity.