The effect of trans-resveratrol on platelet-neutrophil complex formation and neutrophil burst in hypercholesterolemic rats.

Transresveratrol (t-resveratrol; 3,5,4'-trihydroxy-trans-stilbene) is a polyphenolic compound found in fresh grapes, grape juice and wine, and has been found to reduce the total cholesterol level in hypercholesterolemic rats. The objective of the present study was to assess the effects of t-resveratrol on platelet-neutrophil complex formation and neutrophil reactive oxygen species (ROS) status in control and hypercholesterolemic rats using a modified flow cytometric method. Rats (n=80) were divided into five groups (control, ethanol, resveratrol, hypercholesterolemic and resveratrol-administered hypercholesterolemic groups), comprising 16 animals per group. Serum levels of lipids and H2O2 were determined using commercially available kits, while platelet-neutrophil complex formation and neutrophil ROS status were determined using a modified flow cytometric method. Serum total cholesterol and low-density lipoprotein cholesterol levels were found to be increased and the high-density lipoprotein cholesterol level was found to be decreased in the HC group compared with the control group (P<0.001). Treatment of HC rats with t-resveratrol significantly lowered total cholesterol and low-density lipoprotein cholesterol levels (P<0.001). In the hypercholesterolemic group, levels of serum H2O2 platelet-neutrophil complex formation and neutrophil ROS status were significantly increased (P<0.001). On the other hand, in the resveratrol-administered hypercholesterolemic group, serum H2O2 levels, platelet-neutrophil complex formation and neutrophil ROS status were decreased compared with the hypercholesterolemic group (P<0.001). Serum H2O2 levels, platelet-neutrophil complex and neutrophil ROS status were positively correlated with one another. The present study is the first to demonstrate the protective effect of t-resveratrol against hypercholesterolemia-induced platelet-neutrophil complex formation and neutrophil ROS burst. Further investigations on its plausible role in antihypercholesterolemic treatment are warranted.