Resveratrol improves endothelial function in overweight men and women
An article published online on July 29, 2010 in the journal Nutrition, Metabolism & Cardiovascular Disease revealed the results of a double-blinded, crossover clinical trial of overweight and obese individuals which found a benefit for resveratrol in improving flow-mediated dilatation (FMD), a biomarker of endothelial function and cardiovascular health. Impaired functioning of the blood vessels' endothelium, or inner lining, occurs in cardiovascular disease and has been associated with high blood pressure and obesity.
In their introduction to the article, Rachel H. X. Wong and her colleagues at the University of South Australia remark that consumption of polyphenol-rich foods including cocoa, tea, grape seed extract and red wine extract have been demonstrated to improve flood-mediated dilatation, however, the compounds in these foods that are responsible for this effect have not been identified. For their research, 19 overweight or obese men and postmenopausal women aged 30 to 70 with borderline hypertension were given 30, 90 or 270 milligrams resveratrol or a placebo in 4 weekly intervals, and plasma resveratrol and flow-mediated dilatation of the brachial artery were measured one hour later.
Plasma resveratrol increased with dosage, corresponding to improvements in flow-mediated dilatation compared to placebo. In their discussion of the findings, the authors remark that there is evidence that resveratrol could increase endothelium-derived nitric oxide bioavailability, which increases blood vessel dilation.
"The present study is the first to demonstrate that synthetic trans-resveratrol can improve FMD acutely and in a dose-related manner in at-risk population groups," the authors announce. "However, the lowest resveratrol dose (30 mg) used in this study cannot be obtained from normal dietary habits. Whilst the acute improvement in FMD after supplementation is encouraging, it is important to see if this improvement seen in FMD after acute oral resveratrol supplementation is sustainable, given that little is known about the long-term effects of trans-resveratrol in human subjects following chronic supplementation."
"These findings suggest that resveratrol may contribute to the purported cardiovascular health benefits of grapes and red wine," they conclude.
Atherosclerosis is perhaps the single most deadly disease in the United States, yet there is a good chance that most people, even those at high risk for heart disease, don’t really understand how it develops. The fact is, long before any symptoms are clinically evident, atherosclerosis begins as a malfunction of specialized cells that line our arteries. Called endothelial cells, they are the key to atherosclerosis, and underlying endothelial dysfunction is the central feature of this dreaded disease.
Interestingly, only about half the people with coronary artery disease have more traditional risk factors, such as elevated cholesterol, smoking, high blood pressure, and obesity. Yet all patients with atherosclerosis suffer from endothelial dysfunction and the damaging effects of oxidized LDL, which provides an important building block for plaque deposits. Antioxidant therapy is therefore important to limit the oxidization of LDL and improve the health of the endothelium by limiting the damage caused by inflammatory cytokines.
Green tea extracts, which are rich in natural antioxidants and antiplatelet agents, are routinely used in Asia to lower blood pressure and reduce elevated cholesterol. In studies of smokers, 600 mL green tea (not extract) was shown to decrease markers of inflammation and decrease oxidized cholesterol, both of which are intimately involved in the development of atherosclerosis (Lee W et al 2005b). A Japanese study of 203 patients found that the more green tea patients drink, the less likely they are to suffer from coronary artery disease (Sano J et al 2004). This study supported an earlier study that found that greater green tea consumption was related to a reduced presence of coronary artery disease in Japanese men—although not in women (Sasazuki S et al 2000).
Following menopause, circulating levels of estrogen are depleted. Phytoestrogens are plant hormones with estrogenic activity. In postmenopausal women, phytoestrogens appear to have estrogen-like benefits such as protection against osteoporosis (Atkinson C et al 2004; Crisafulli A et al 2004a) and possibly hot flashes (Crisafulli A et al 2004b). Phytoestrogens have also been shown to improve vascular function, which tends to decline with age. In one study genistein, a phytoestrogen, provided in a daily 54-mg supplement for one year, significantly improved endothelium-dependent vasodilation in postmenopausal women. Moreover, its benefits were as substantial as those observed in women receiving an estrogen-progestin regimen (Squadrito F et al 2003).
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UTIRose™ is derived from Hibiscus sabdariffa, a species native to Europe, Asia, and Africa. Scientific analysis has shown that this species’ flower and calyx (the green floral envelope surrounding the blossom) are rich in active polyphenols, including flavonoids, sambubiosides, and proanthocyanidins.
Of special importance is a flavonoid found in Hibiscus sabdariffa called gossypetin (3,5,7,8,3,’ 4’-hexahydroxy flavone), which has been shown to provide support for urinary system health. Life Extension uses a unique, patented process in the manufacture of Optimized Cran-Max® with UTIRose™. Each capsule supplies the complete phenolic profile of the whole cranberry plus hibiscus polyphenols in a standardized, highly absorbable, concentrated form.
Just as meditation, massage or aromatherapy quiets the mind and body, theanine plays a role in inducing the same calm and feeling of well-being without drowsiness. It is a non-toxic, highly desirable mood modulator.
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