Background: Methotrexate, used to treat cancer and autoimmune disorders, can damage testicular tissue, disrupt spermatogenesis, and cause infertility by reducing cellular antioxidant capacity and increasing reactive oxygen species. Rutin, as a flavonoid, has high antioxidant capacity and reduces the effects of reactive oxygen species on sperm quality. Objective: This study investigated the potential protective effects of rutin, a natural flavonoid with antioxidant properties, on sperm parameters in NMRI mice exposed to methotrexate. Materials and Methods: In this experimental study, 40 adult NMRI male mice (average weight: 31 gr) were randomly divided into four groups (n = 8): group 1 (control), groups 2 and 3 received at the end of the 3 rd wk, a single dose of 20 mg/kg/bw of methotrexate by intraperitoneal injection. Groups 3 and 4 received 100 mg/kg/bw rutin for 35 days by oral gavage every other day. Following dissection, the caudal epididymis was placed in a plate containing Ham's F10 culture medium, and the extracted sperm were analyzed for various sperm parameters. Results: The methotrexate group showed a significant reduction in the mean number, viability, motility, and membrane integrity of the sperm cells when compared to the control group (p ≤ 0.001). However, these parameters significantly increased in the methotrexate + rutin group compared to the methotrexate group (p ≤ 0.000). Conclusion: Our results revealed that rutin, a potent antioxidant, can mitigate the adverse effects of methotrexate on sperm parameters.
