Red wine polyphenols induce vasorelaxation by increased nitric oxide bioactivity.

Area of Science:

• Cardiovascular Pharmacology
• Natural Product Chemistry

Background:

• Red wine polyphenols are known for their potential health benefits, including cardiovascular effects.
• Understanding the precise mechanisms of action of these compounds is crucial for their therapeutic application.

Purpose of the Study:

• To investigate the vasorelaxant mechanism of red wine polyphenolic compounds (Provinol) in rat femoral arteries.
• To elucidate the role of the endothelium and nitric oxide (NO) in Provinol-induced vasodilation.

Main Methods:

• Isometric tension recording in rat femoral artery rings with or without functional endothelium.
• Cumulative dose-response curves for phenylephrine, Provinol, acetylcholine, and sodium nitroprusside.
• Assessment of nitric oxide synthase (NOS) activity and modulation with L-NAME and L-arginine.
• Evaluation of calcium (Ca2+) influx and oxidative stress (H2O2) effects.

Main Results:

• Provinol induced a dose-dependent, endothelium-dependent relaxation of rat femoral arteries.
• Relaxation correlated with increased NO synthase activity and was attenuated by L-NAME, but restored by L-arginine.
• Provinol-induced relaxation was abolished by verapamil, indicating a role for Ca2+ influx.
• Provinol protected acetylcholine-induced relaxation from H2O2-induced impairment, suggesting antioxidant properties.

Conclusions:

• Provinol elicits endothelium-dependent vasodilation via a mechanism involving calcium-induced NO synthase activation.
• Provinol also protects nitric oxide from degradation, contributing to its overall vasorelaxant effect.
• These findings highlight the cardiovascular protective potential of red wine polyphenols through modulation of vascular function.