Protective effects of thioredoxin on ischemia/reperfusion-induced damaged testicular tissue after testicular torsion in rats

Abstract

Objective The aim of this study was to examine the effectiveness of thioredoxin on the prevention of testicular damage induced by ischemia/reperfusion(I/R)in rats.Methods Male Sprague Dawley rats(n=60)were divided randomly into 4 experimental groups:sham group,torsiondetorsion(TD)group,TD+saline group,and TD+thioredoxin group.Testicular ischemia was achieved by twisting the left testis for 4 hours,and reperfusion was allowed for 4 hours after detorsion.Human thioredoxin was injected intraperitoneally to rats in D group at time point of 15 min before detorsion.Left orchiectomies were harvested for tissue histopathological examinations.The detection of superoxide dismutase(SOD)activities and malondialdehyde(MDA)levels were also conducted.Results Interstitial edema,dilatation,and degeneration of germ cells in tubules were observed after TD.Testicular tissues in D group showed an improved histological morphology.Testicular injury score in B group and C group(8.3±0.96;8±0.87)were significantly increased compared with those in the Sham group(0.78±0.36)(P＜0.01).It was observed that scores(3.1±0.42)were significantly lower in D group compared with B and C groups(P＜0.05).The MDA concentration(4.39±0.21;4.42±0.17)and SOD activities(269±27.1;271±21.3)in B and C group were increased and decreased respectively as compared with the Sham group(MDA:1.61±0.18;SOD:317±22.3)(P＜0.01).Treatment of rats with human thioredoxin significantly reduced the tissue MDA levels(2.03±0.03)(P＜0.01).SOD activities(315±24.2)were increased in testes in D group(P＜0.01).Conclusions The results provide biochemical and histopathological evidence for human thioredoxin to be used as a therapeutic agent for the testicular damage induced by I/R injury. Key words: Thioredoxin; Testicular torsion; Ischemia-reperfusion injury; Superoxide dismutase; Malondialdehyde