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

Acute renal failure is a renal disease affecting about 5% of hospitalized p atients, for which no specific therapy is available. Although the care of i njured patients has improved, acute renal failure still carries a mortality rate of over 50%. Ischemia is a predisposing factor in 50% of incidences o f acute renal failure and increases the risk of organ rejection after renal transplantation. There is increasing evidence that leukocytes, particularl y neutrophils [polymorphynuclear cells (PMNs)], mediate tissue injury and p lay a key role in the development of renal failure. Because resveratrol, a natural polyphenol in grapes and wine, was found to reduce renal ischemia/r eperfusion injury in vivo by an antioxidant mechanism, we evaluated the eff ect of resveratrol pretreatment (1 muM administered 40 min before bilateral renal clamping) on the inflammatory response to ischemia/reperfusion injur y of rat kidney (40 min ischemia and 24 h reperfusion). Resveratrol pretrea tment significantly reduced PMN infiltration in ischemia/reperfusion rats b oth 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, PM N cells/microscopic field, p <0.01). The lower organ infiltration was assoc iated with improved renal function, reduced tissue lipid peroxidation and i nterleukin-6 urinary excretion. In conclusion, resveratrol pretreatment red uces parenchymal inflammation in ischemia/reperfusion rat kidneys, thus red ucing PMN organ infiltration.