Submitted to: Journal of Nutritional Biochemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/6/2001
Publication Date: 5/9/2002
Citation: Youdim, K.A., Mcdonald, J., Kalt, W., Joseph, J.A. 2002. Potential role of dietary flavonoids in reducing microvascular endothelium vulnerability to oxidative and inflammatory insults. Journal of Nutritional Biochemistry. 13:282-288. Interpretive Summary: Antioxidant systems within the body, which normally protect the body from oxidative and inflammatory damage, may become overwhelmed during periods of increased oxidative stress, such as in aging. Increases in oxidative stress and inflammation may lead to damage to the endothelial tissue (lining of the arterial walls) resulting in vascular disorders such as atherosclerosis (heart disease). Polyphenolic compounds are functional compounds found in plants that have been shown to have antioxidant and anti-inflammatory properties. Consequently, this study investigated the putative antioxidant and anti-inflammatory effects of polyphenols isolated from blueberry and cranberry extracts against damage to endothelial cells. The polyphenols from both berries were able to enter the endothelial cells and subsequently decrease the cells vulnerability to oxidative stress. Furthermore, the berry polyphenols also reduced signs of inflammation. In conclusion, polyphenols found in both blueberry and cranberry were able to protect endothelial cells from oxidative and inflammatory insult, which could have implications for the development of vascular diseases. Polyphenols could also be a contributing factor in the reduction of age-related deficits in brain functioning as previously reported.
Technical Abstract: Although antioxidant systems help control the level of reactive oxygen species they may be overwhelmed during periods of oxidative stress. Evidence suggests that oxidative stress components as well as inflammatory mediators may be involved in the pathogenesis of vascular disorders, where localized markers of oxidative damage have been found. In this regard we investigated the putative antioxidant and anti-inflammatory effects of blueberry and cranberry anthocyanins and hydroxycinnamic acids against H(2)O(2) and TNFalpha induced damage to human microvascular endothelial cells. Polyphenols from both berries were able to localize into endothelial cells subsequently reducing endothelial cells vulnerability to increased ocidative stress at both the membrane and cytosol level. Furthermore, berry poyphenols also reduced TNFalpha induced up-regulation of various inflammatory mediators (IL-8, MCP-1 and ICAM-1) involved in the redruitment of leukocytes to sites of damage or inflammation along the endothelium. In conclusion, pol6yphenols isolated from both blueberry and cranberry were able to afford protection to endothelial cells against stressor inducedup-regulation of oxidative and inflammatory insults. This may have beneficial actions against the initiation and development of vascular diseases and be a contributing factor in the reduction of age-related deficitsin neurological impairments previously reported by us.