Effect of resveratrol on platelet aggregation in vivo and in vitro / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>Low or moderate consumption of red wine has a greater benefit than the consumption of other beverages in the prevention of atherosclerosis and coronary heart disease and this is increasingly attributed to the polyphenol compounds in red wine, such as resveratrol. In the present study, we investigated the effect of resveratrol on platelet aggregation in vitro and in vivo.</p><p><b>METHODS</b>Platelet aggregation in rabbits and normal subjects was measured using Born's method.</p><p><b>RESULTS</b>Resveratrol, at 10 - 1000 micromol/L, significantly inhibited platelet aggregation in vitro induced by collagen, thrombin, and ADP in healthy subjects. The inhibitory effect was concentration-dependent. Hypercholesterolemia induced by high-cholesterol diet enhanced ADP-induced platelet aggregation. Resveratrol 4 mg x kg(-1) x d(-1) inhibited ADP-induced platelet aggregation in vivo despite no changes in serum lipid levels.</p><p><b>CONCLUSIONS</b>Resveratrol inhibits platelet aggregation both in vitro and in vivo. This may be one of the mechanisms by which resveratrol prevents atherosclerosis.</p>

Stress and atherogenesis: smooth muscle cell mitogenic activity and other biochemical changes associated with sera of stressed subjects

The proliferation of smooth muscle cells in the arterial wall [VSMC] is considered to play a key role in the development of atherosclerosis. To investigate the possible contribution of "stress" [experimentally induced] to this process, blood from healthy volunteers, ages 21 to 65, screened to exclude major risk factors for coronary heart disease, was assayed for mitogenic activity after the subjects were exposed to one of 2 "stress" conditions. These consisted of a cognitive task with superimposed verbal harassment [group 1], and the cognitive task without harassment [group 2]. Mitogenic activity was determined by studying the growth stimulatory effects of PDGF-depleted plasma derived serum [PDS] from "stressed" subjects added to cultured VSMC, as measured by incorporation of radioactive thymidine into DNA or increase in cell number. In addition, changes in the steady state of the mRNA for the c-myc protooncogene were also assayed in VSMC by Northern blot analysis, using sera showing the greatest differential "pre/post stress" mitogenic activity. Blood pressure [BP], heart rate [HR], cortisol, and serum total and HDL cholesterol were also evaluated. All measurements were made immediately before [baseline] and after a 30 min interval. Analysis of the data revealed that there were 33% of subjects in group 1 with an increase of thymidine incorporation 15% or greater than baseline, versus 21% in group 2. The average increases were 45% and 30%. A higher percentage [35-42%] of subjects in group 1 responded with increases in systolic and diastolic blood pressure, compared to subjects in group 2 [15-20%]; the average in blood pressure was 10-15%. Similarly, more subjects [52%] in group 1 had an elevated [average 10-15%] serum cortisol, compared to the 42% in group 2 subjects. HR, total HDL cholesterol showed slight changes only. These results suggest that psychoactive factors may affect cardiovascular systems via rapid elicited rises in serum mitogenic activity for VSMC