Epigallocatechin-3-gallate inhibits apoptosis and protects testicular seminiferous tubules from ischemia/reperfusion-induced inflammation

摘要

Testicular torsion (TT) is a urologic emergency that may result in future infertility problems. The pathologic process of TT is similar to an ischemia reperfusion injury (IRI). The purpose of this study was to evaluate the effect of epigallocatechin-3-gallate (EGCG) on reversing the damaging consequences of TT-induced IRI by examining its inhibitory effects on the expression of inflammatory and apoptosis mediators in a unilateral TT rat model. Eighteen male Sprague-Dawley rats were divided into 3 groups. Group 1 underwent a sham operation of the left testis under general anesthesia. Group 2 underwent ischemia for 1. h followed by 4. h reperfusion in the presence of saline. The third group was similar to group 2, however, EGCG (50. mg/kg) was injected i.p. 30. min after ischemia induction. The in vivo protective effect of EGCG was tested by measuring testicular levels of TNF-α, IL-6 and IL-1β by ELISA and mRNA expression of iNOS, MCP-1, p53, Bax, Bcl-2 and survivin by real-time PCR. Also, testicular morphological changes and damage to spermatogenesis were evaluated using H&E staining and Johnsen's scoring system, respectively. EGCG treatment improved testicular structures in the ipsilateral testis, markedly inhibited germ cell apoptosis (GCA) and significantly decreased testicular cytokine levels. In addition, EGCG was able to down regulate the mRNA expression of iNOS, MCP-1 and pro-apoptosis genes in favor of cell survival. For the first time we show that in vivo EGCG treatment rescued the torsed testes from IRI-induced inflammation, GCA and damage to spermatogenesis thus suggesting a new preventive approach to inhibiting the inflammatory and apoptotic consequences of TT-induced IRI.