Pumpkin seed oil attenuates colchicine-induced splenic injury: Evidence from oxidative stress, immune, and apoptosis-related biomarkers.

Colchicine (COL) is a widely used anti-inflammatory agent, but its therapeutic potential is limited by its toxicity, particularly in the spleen. This study investigates the protective role of pumpkin seed oil (PMNO) against COL-induced immune dysregulation in male rats. Forty male Sprague-Dawley rats were divided into four groups: control, PMNO (4 mL/kg b.wt), COL (0.6 mg/kg b.wt), and COL + PMNO. After 56 days, COL administration significantly increased serum IgG, IgM, and complement C3 levels, while significantly reducing nitric oxide concentrations. PMNO co-treatment significantly restored these parameters to baseline values. COL exposure also induced pronounced oxidative stress in splenic tissue, as evidenced by increased levels of 8-hydroxy-2'-deoxyguanosine, protein carbonyls, and malondialdehyde, accompanied by significant reductions in the antioxidant defenses, including superoxide dismutase, catalase, and reduced glutathione. PMNO treatment significantly reduced oxidative stress markers, improving redox balance. Histopathological examination revealed spleen damage in COL-treated rats, including mild depletion of white pulp, expansion of red pulp, and collagen accumulation. PMNO co-treatment alleviated these changes and reduced collagen deposition. Immunohistochemical analysis revealed a marked reduction in proliferating cell nuclear antigen immunoreactivity and a significant increase in BAX expression in the spleens of COL-treated rats. These alterations were markedly attenuated by PMNO co-administration. These findings suggest that PMNO protects against COL-induced splenic injury, as evidenced by improvements in immune-related biomarkers, oxidative stress indices, histopathological alterations, and apoptosis-associated markers, highlighting its potential as a natural therapeutic agent for mitigating COL-associated splenic injury.