The protective effect of erythropoietin and dimethylsulfoxide on ischemia-reperfusion injury in rat ovary.

OBJECTIVES: The aim of this study was to investigate the effects of erythropoietin and dimethylsulfoxide in the recovery from ischemia-reperfusion injury in an experimental rat adnexal torsion model. STUDY DESIGN: Thirty-six Wistar-albino rats were divided into six groups. Except for the sham operation group, all groups were subjected to left unilateral adnexal torsion for 3h. Erythropoietin and dimethylsulfoxide were intraperitoneally administered 30min before the detorsion operation. Malondialdehyde and nitric oxide levels were detected from both the plasma and the tissue samples. The sections of the tissues were evaluated histologically. The results were analyzed by a one-way analysis of the variance (ANOVA) followed by the Duncan test for multiple comparisons using computer software, SPSS Version 15.0 for Windows. RESULTS: This study demonstrated that dimethylsulfoxide and erythropoietin pretreatment attenuated ischemia-reperfusion-induced lipid peroxidation, prevented post-ischemic ovarian injury and helped to maintain the ovarian morphology. Malondialdehyde levels of plasma and ovary were higher in the torsion and detorsion groups than the sham group. This showed that ischemia-reperfusion had caused lipid peroxidation of the ovarian tissue, thus leading to oxidative damage. One of the major findings of this study is that malondialdehyde was significantly decreased in the plasma of rats who were pre-treated with dimethylsulfoxide and erythropoietin before detorsion. This suggests that dimethylsulfoxide and erythropoietin might prevent oxidative damage in ovarian ischemia-reperfusion injury. Histological examination confirmed that reperfusion caused more detrimental effects than only ischemia, which could be at least partially prevented by dimethylsulfoxide and erythropoietin administration prior to detorsion. CONCLUSION: Erythropoietin and dimethylsulfoxide may have beneficial effects in ischemia-reperfusion injury in ovarian torsion.

Protective effects of N-acetylcysteine on cyclosporine-A-induced nephrotoxicity.

OBJECTIVES: Cyclosporine A (CsA) is used for the treatment of autoimmune and inflammatory disorders. However, CsA-induced nephrotoxicity remains an important clinical problem, and oxidative stress has been implicated as a possible responsible mechanism. We assessed the protective ability of N-acetylcysteine (NAC), an antioxidant, against CsA-induced nephrotoxicity. MATERIALS AND METHODS: Wistar albino rats were randomly assigned into four groups. Group 1 rats were treated with sodium chloride as control, group 2 with CsA, group 3 with CsA and NAC, and group 4 with NAC alone. Animals were sacrificed and blood samples were analyzed for blood urea nitrogen (BUN), serum creatinine (Cr), malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Kidney sections were analyzed for MDA and NO levels and SOD and GSH-Px activities, as well as histopathological changes. RESULTS: Overall, the treatment of rats with CsA alone produced significant increases in NO and MDA levels and significant decreases in SOD and GSH-Px activities in serum and renal samples. Morphological changes, including tubular epithelial atrophy, vacuolizations, and cellular desquamations, were clearly observed in the rats treated with CsA alone. Concurrent NAC administration with CsA improved renal function, as indicated by lower BUN and Cr values. Moreover, NAC significantly reduced MAD and NO levels and increased SOD and GSH-Px activities in serum and renal tissue, as well as provided a histologically proven protection against CsA-induced nephrotoxicity. CONCLUSION: These results indicate that NAC produces a protective mechanism against CsA-induced nephrotoxicity and suggest a role for oxidative stress in pathogenesis.

The protective role of erdosteine on testicular tissue after testicular torsion and detorsion.

Testicular torsion and detorsion are important clinical problems for infertile man and oxidative stress may have a role in this clinical situation. The aim of this study was to investigate the protective role of erdosteine, an antioxidant, on unilateral testicular reperfusion injury in rats. The rats were divided into four groups including seven rats in each group: control, torsion, torsion/detorsion and torsion/detorsion+erdosteine. Rats, except the sham operation group, were subjected to left unilateral torsion (720( composite function) rotation in the clockwise direction) without including the epididymis. The experiments were finished after sham operation time for control, 120 min torsion for torsion group and 120 min torsion and 240 min detorsion for torsion/detorsion groups. Bilateral orchiectomy was performed for all groups of rats. The ipsilateral and controlateral testis were divided into two pieces to analyse biochemical parameters and to investigate the light microscopic view. Malondialdehyde level of ipsilateral testis was increased in torsion and torsion/detorsion groups in comparison with the other groups (p < 0.05). Erdosteine treatment ameliorated lipid peroxidation after torsion/detorsion in ipsilateral testis (p < 0.05). Also, xanthine oxidase activity of ipsilateral testis was increased in torsion/detorsion group in comparison with the others (p < 0.05). Nitric oxide (NO) level of ipsilateral testis was higher in all experimental groups than sham operated control group (p < 0.05). Also, NO level of torsion group was increased in comparison with detorsion groups (p < 0.05). Erdosteine treatment caused increased glutathione peroxidase activity in comparison with torsion and torsion/detorsion groups and catalase activity in comparison with the other groups in ipsilateral testis (p < 0.05). Superoxide dismutase activity of ipsilateral testis was higher in torsion/detorsion and torsion/detorsion+erdosteine groups than control and torsion groups (p < 0.05). The biochemical parameters were not affected in controlateral testis in all groups. Torsion, torsion/detorsion and torsion/detorsion+erdosteine groups showed ipsilateral testicular damage in the histological examination, but the specimens from torsion/detorsion had a significantly greater histological injury than those from the other groups (p < 0.05). Control rats showed normal seminiferous tubule morphology. Rats in torsion group had slight-to-moderate disruption of the seminiferous epithelium. Rats in torsion/detorsion group displayed moderate-to-severe disruption of the seminiferous epithelium. In all animals from torsion/detorsion+erdosteine group, the testicular tissues were affected with slight-to-moderate degenerative changes of the seminiferous epithelium. Administration of erdosteine resulted in a significantly reduced histological damage associated with torsion of the spermatic cord compared with torsion/detorsion. In all groups, the contralateral testes were histologically normal. In conclusion, the results clearly displayed that erdosteine treatment may have a protective role on testicular torsion/detorsion injury.