[ role of dietary polyphenols on attenuation of cardiovascular complications in type 2 diabetes: a review of studies]

ABSTRACT

Type 2 diabetes is a common metabolic disorder accompanied by increased risk of cardiovascular diseases, along with increased morbidity and mortality. In recent years, epidemiological evidence and clinical studies have indicated that dietary polyphenols and phytochemical-rich foods have key role in prevention of cardiovascular diseases, especially coronary heart disease and myocardial infarction. The current review was conducted to investigate the mechanism of the effects of polyphenols in natural foods on prevention of diabetes-induced cardiovascular diseases. "polyphenols", "phenolic acids", "anthocyanins", "flavonoids", and "lignans" in combination with "type 2 diabetes", "insulin resistance", "cardiovascular disease", "endothelial dysfunction", "oxidative stress", "inflammation", "lipid disorders", and "hypertension" were used as key words for search in PubMed between 1990 and 2013. Cellular studies, animal models and clinical trials with appropriate design, and review article with high quality were used. Dietary polyphenols have high potential to improve lipid profiles through decrease in digestion and ingestion of dietary fats, increase in turnover and excretion of cholesterol, reduction of synthesis of atherogenic apo lipoproteins, and inhibition of cholesterol and triglycerides synthesis. These compounds protect vascular endothelium against oxidative damages and inflammatory processes, improve function of vascular endothelium, modify the pathways related to platelets and coagulation, and even protect cardiac tissue and improve myocardial hemodynamics. Higher consumption of foods containing polyphenols and using polyphenol-rich natural extract can be useful in decreasing the risk of development of cardiovascular diseases in type 2 diabetic patients.