Antioxidant treatment with edaravone or taurine ameliorates diabetes-induced testicular dysfunction in the rat

Division of Urology, Department of Surgery, Tottori University School of Medicine, 86 Nishimachi, Yonago, Japan.
Molecular and Cellular Biochemistry (Impact Factor: 2.39). 07/2012; 369(1-2):195-204. DOI: 10.1007/s11010-012-1382-z
Source: PubMed

ABSTRACT Diabetes mellitus with the subsequent generation of reactive oxygen species represents a major risk factor for testicular dysfunction (TD). We investigate whether administration of antioxidants edaravone and taurine could prevent type 1 diabetes-induced TD in the rat. Six-week-old male Wistar rats were divided into four groups. Group A was treated with citrate-phosphate buffer plus normal saline, whereas in the other three groups, diabetes was induced by streptozotocin (50 mg/kg intraperitoneally). Subsequently, the diabetic rats were treated for 4 weeks either with normal saline (group B), edaravone (10 mg/Kg/day, intraperitoneally; group C), or taurine (500 mg/Kg/day, intraperitoneally; group D). Body, testicular, and epididymal weight, serum glucose, malondialdehyde levels, 8-Hydroxy-2'-deoxyguanosine(8-OH-dG) levels, testicular catalase activity, and serum testosterone levels were determined. Histological examination and the Johnsen score were used to observe and evaluate, respectively, the morphological changes in the testes. TUNEL assay was used to examine DNA fragmentation. Mating studies were performed in order to evaluate the fertility potential of male rats in each group. Edaravone or taurine treatment prevented significantly the decreased body, testicular, and epididymal weight induced by diabetes. Moreover, edaravone or taurine significantly decreased the diabetes-induced malondialdehyde levels, 8-OHdG levels, the morphological damage, and the number of apoptotic cells. Taurine, but not edaravone, increased significantly the testicular catalase activity. The antioxidant treatment had no effect on the fertility potential of the diabetic rats. The morphological damage, increased lipid peroxidation, and apoptosis in testicular tissue can be significantly relieved by edaravone or taurine treatment through suppressing the increased oxidative stress in the rat testis.

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Available from: Panagiota Tsounapi, Jul 06, 2015
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