Pretreatment with resveratrol, a natural compound from grapes and wine, decreases ischemia/reperfusion-induced polymorphonuclear cell infiltration in rat kidney

Acute renal failure is a renal disease affecting about 5% of hospitalized patients, for which no specific therapy is available. Although the care of injured patients has improved, acute renal failure still carries a mortality rate of over 50%. Ischemia is a predisposing factor in 50% of incidences of acute renal failure and increases the risk of organ rejection after renal transplantation. There is increasing evidence that leukocytes, particularly neutrophils [polymorphynuclear cells (PMNs)], mediate tissue injury and play a key role in the development of renal failure. Because resveratrol, a natural polyphenol in grapes and wine, was found to reduce renal ischemia/reperfusion injury in vivo by an antioxidant mechanism, we evaluated the effect of resveratrol pretreatment (1 muM administered 40 min before bilateral renal clamping) on the inflammatory response to ischemia/reperfusion injury of rat kidney (40 min ischemia and 24 h reperfusion). Resveratrol pretreatment significantly reduced PMN infiltration in ischemia/reperfusion rats both in the glomerull (7.4 +/- 2.6 vs. 16.2 +/- 3.1 PMN cells/glomerulus, p <0.01) and in the peritubular interstitium (4.8 +/- 2.1 vs. 9.2 +/- 2.2, PMN cells/microscopic field, p <0.01). The lower organ infiltration was associated with improved renal function, reduced tissue lipid peroxidation and interleukin-6 urinary excretion. In conclusion, resveratrol pretreatment reduces parenchymal inflammation in ischemia/reperfusion rat kidneys, thus reducing PMN organ infiltration.