Does protocatechuic acid, a natural antioxidant, reduce renal ischemia reperfusion injury in rats?

BACKGROUND: Protocatechuic acid (PCA), which has antioxidant property, is a simple phenolic compound commonly found in many plants, vegetables, and fruits, notably in green tea and almonds. Present study was an investigation of the effects of PCA on rat kidney with ischemia/reperfusion (IR) injury. METHODS: Sprague-Dawley rats were randomly divided into 4 groups: (1) Sham, (2) Renal IR, (3) Renal IR+ Vehicle, and (4) Renal IR+ PCA. Renal reperfusion injury was induced by clamping renal pedicle for 45 minutes after right nephrectomy was performed, followed by reperfusion for 3 hours. Dose of 80 mg/kg PCA was intraperitoneally administered to 1 group immediately before renal ischemia; 33% polyethylene glycol was used as vehicle. Total antioxidant status (TAS), malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor alpha (TNF-alpha), and interleukin-6 levels were measured in blood and kidney tissue samples taken from sacrificed rats. Kidney tissue samples were examined and scored histopathologically. Terminal deoxynucleotidyltransferase-mediated dUTP digoxigenin nick end labeling assay method was used to detect apoptotic cells. RESULTS: It was found that PCA significantly reduced serum MDA, TNF-alpha, and kidney MDA levels, while it increased serum and kidney TAS and SOD levels. Histopathological scores were significantly higher for the group given PCA. CONCLUSION: PCA reduced oxidative stress and can be used as an effective agent in treatment of renal IR injury.