Polyphenol (-)-Epigallocatechin Gallate Protection from Ischemia/Reperfusion-Induced Renal Injury in Normotensive and Hypertensive Rats

Abstract

Introduction. The effect of epigallocatechin gallate (EGCG) in an in vivo renal model of ischemia with reperfusion (I/R) was compared between normotensive (WKR) and hypertensive (SHR) rats. Methods. WKR (groups I, II, III) and SHR groups (groups IV, V, VI) were divided into three types. Groups I and IV were sham-operated animals; groups II and V were subjected to 45 minutes of renal I/R; and groups III and VI received 10 mg/kg EGCG intravenously at the time of reperfusion. Three days after renal I/R, we compared renal function markers, malondialdehyde (MDA), and histologic changes. Results. Following renal I/R, levels of blood urea nitrogen (BUN) and serum creatinine (sCr) were increased and serum creatinine clearance (CrCl) decreased in group V compared to group II (P .001). Those receiving EGCG treatment (groups III and VI) had decreased BUN and sCr compared to non-EGCG I/R groups (P .001), but not surprisingly, higher than sham groups. CrCl was lowest in the SHR groups. The MDA was significantly decreased after EGCG treatment (P .028 in group III, P .002 in group VI). Following renal I/R, tissue necrosis was more severe among SHR (P .001). However, the ratio of regeneration to damage significantly increased in SHR after EGCG treatment. Conclusions. The reperfusion injury was greater among SHR compared with WKR in terms of renal function, lipid peroxidation, and tissue damage. EGCG treatment significantly ameliorated renal impairment and promoted tissue regeneration following renal I/R.