Effect of L-ascorbic add supplementation on testicular oxidative stress and endocrine disorders in mature male rats exposed to intensive swimming exercise

Abstract

In order to investigate the ameliorative potential of L-ascorbic acid on intensive swimming exercise induced testicular oxidative stress, 18 Wistar male rats (age: 3months, weight: 127.5±5.3g) were randomly divided into the following groups: (i) control group (CG, n=6); (ii) experimental group (EG, n=6); and (iii) supplemented group (SG, n=6). An exercise protocol of 3h swimming per day, five days per week was followed for 6weeks in EG and SG with no exercise in CG. In SG, L-ascorbic acid was supplied orally at a dose of 25-mg/kg of bodyweight each day for 6weeks. A significant decrease (P<0.05) was noted in paired testicular weights, epididymal sperm count, testicular Δ5, 3β-hydroxyseroid dehydrogenase, 17β-hydroxyseroid dehydrogenase, plasma levels of testosterone luteinizing hormone, follicle stimulating hormone, prolactin, the numbers of preleptotine spermatocytes, midpachytene spermatocytes and stage7 spermatids of stage VII seminiferous epithelium cycle in EG when compared with CG. A significant elevation (P<0.05) in plasma corticosterone and testicular content of malondialdehyde along with a significant reduction (P<0.05) in glutathione, ascorbic acid, α-tocopherol, superoxide dismutase, catalase and glutathione-peroxidase, and glutathione-S-transferase were noted in testes of EG compared with CG. No significant change was noted in final bodyweight or numbers of spermatogonia-A among the groups. Furthermore, L-ascorbic acid supplementation restored the above parameters to the control level. Conclusion: It can be concluded that intensive swimming exercise induced oxidative stress causes dysfunctions in the male reproductive system, which can be protected by L-ascorbic acid. (Reprod Med Biol 2006; 5: 145-153).