Polyphenol-enriched diet prevents coronary endothelial dysfunction by activating the Akt/eNOS pathway

Area of Science:

• Cardiovascular Research
• Nutritional Science
• Pharmacology

Background:

• The Mediterranean diet, rich in polyphenols, is linked to cardioprotection, but mechanisms are unclear.
• Polyphenols, abundant in pomegranate, are hypothesized to mediate these cardiovascular benefits.
• Understanding pomegranate extract's impact on coronary function is crucial for developing dietary interventions.

Purpose of the Study:

• To investigate the effects of pomegranate extract (Pomanox) on coronary function in a hyperlipidemic model.
• To elucidate the underlying mechanisms, including the Akt/endothelial nitric oxide-synthase (NOS) pathway, inflammation, and oxidative stress.
• To assess the impact of pomegranate extract on endothelial relaxation and vascular health.

Main Methods:

• Pigs were fed normocholesterolemic or hypercholesterolemic diets for 10 days.
• Half of the animals received daily pomegranate extract (Pomanox) supplementation.
• Coronary responses to vasoactive drugs and L-NG-monomethylarginine were measured; Akt/eNOS activation, inflammation, and oxidative damage were evaluated.

Main Results:

• Pomanox supplementation prevented diet-induced endothelial dysfunction in hyperlipidemic pigs, restoring vasodilation.
• Beneficial effects were linked to increased vascular Akt/eNOS activation and reduced monocyte chemoattractant protein-1 expression.
• Pomanox reduced systemic oxidative stress and coronary DNA damage, enhancing lipoprotein resistance to oxidation.

Conclusions:

• Pomanox supplementation effectively counteracts hyperlipemia-induced coronary endothelial dysfunction.
• The mechanism involves activation of the Akt/endothelial nitric oxide-synthase pathway.
• Pomanox favorably modulates vascular inflammation and oxidative damage, supporting its cardioprotective potential.