Impact of tea polyphenols on serum superoxide dismutase and malondialdehyde in renal ischemia reperfusion rat

Objective:To explore the protective effects and its mechanism of tea polyphenols on renal ischemia reperfusion injury in rats models. Methods: Fourty-two SD male rats were randomly divided into 3 groups: sham-operated group, renal ischemia reperfusion injury (IRI) groups (non-invasive artery folder clap the left renal pedicle one hour then reperfusion) and tea polyphenols precondiontioning groups (TP 200 mg/kg gavage before one week). The levels of serum creatinine (Scr), malondialdehyde (MDA) and activity of serum superoxide dismutase (SOD) in each group were respectively detected after renal ischemia reperfusion for 0 h, 2 h and 24 h, Pathological changes were also examined by light microscope. Results: Renal pathological lesions of tea polyphenols preconditioning group reduced significantly compared with renal IRI group (P0.05), renal interstitial edema, hyperemia, inflammatory cell infiltration were not obvious. Degeneration and necrosis of renal tubular epithelial cells, epithelial cells shed, narrowed tubular, renal interstitial edema, congestion and massive infiltration of inflammatory cells in renal IRI group. the level of Scr, MDA decreased significantly (P0.05) while the activity of SOD improved significantly (P0.05) in renal IRI group compare with false groups at different time points, tea polyphenols preconditioning improved the activity of SOD significantly (P0.05),decreased the level of Scr, MDA significantly (P0.05), comparing with renal IRI groups at different time points. Conclusion: Tea polyphenols could protect the kidney from renal ischemia reperfusion injury by enhancing the activity of SOD and remove excess oxygen free radicals reducing the generation of MDA.