Resveratrol is a naturally occurring phyloalexin produced by some plants in response to an injury or pathophysiologyical conditions. Alexin means “to protect” and resveratrol does have alexin like activity for humans. Resveratrol naturally occurs from skin of red grapes (Vitis vinifera). Wine is most notable dietary source since 1floz of red wine contains approximate 160 picograms of resveratrol.
Roots of white hellebore and peanuts also contain resveratrol.Researchers at the university of Alabama found that the diabetics with nerve damage improved significantly simply by incorporating peanuts and other myoinositol-rich foods into the diet.
Resveratrol content in different food and beverages is as follows:
Grapes: 1500(?G/100G), OyG/125 ml) Red wine: 625 (?G/100G), OyG/125 ml) White wine: 38(?G /100G), OyG/125 ml) Grape juice: 65(?G/100G), OyG/125 ml)
Cranberry juice: 65(?G /100G), OyG/125 ml)
Different varieties of red grapes differ in resveratrol concentration, their values ranging from 1-13 mg/wt. Resveratrol induces phase II detoxification enzymes that have shown to inhibit proliferation of hepatoma cells.
Resveratrol acts on sirtuin receptors. Sirtuins can regulate steroid hormone signaling through a variety of molecular mechanisms, including acting as co-regulatory transcription factors, deacetylating histones in the promoters of genes with nuclear receptor binding sites, directly deacetylating steroid hormone nuclear receptors, and regulating pathways which modify steroid hormone receptors through phosphorylation. Furthermore, disruption of sirtuin activity may be an important step in the development of steroid hormone-refractory cancers. Resveratrol has also shown to inhibit development of preneoplastic lesions when mice were exposed to tumor initiators and promoters. It interferes with all the stages of carcinogenesis-initiation, promotion and progression. It reduces proliferation rate and increases apoptosis in cancer cell lines in dose dependent manner.COX-2 is antiapoptotic and is implicated in malignancy. Resveratrol induces COX-2 accumulation in human breast cancer cells. The induction of COX-2 accumulation by Resveratrol is mitogen activated protein kinase .COX-2 in turn co localizes proteins that facilitate apoptosis in cancer cells. Resveratrol is partial estrogen receptor agonist but in presence of estrogens it acts as an antagonist to receptor resulting in breast cancer inhibition.
Resveratrol has also shown to revitalize nerve cellsand is also active against herpes simplex virus (type 1 and 2). It also inhibits viral replication.
Resveratrol is an antioxidant, antinflammatory and antiplatelet agent. Research has shown that resveratrol when added to growth culture of yeast; it increases cell life span of yeast by 80%. Generally yeast live for 19 generations but addition of resveratrol increased their life expectancy to 38 generations.
It also has anti-aging qualities, but the major dietary source of resveratrol, that is red wine, has major disadvantage of being an alcoholic drink which can be abused.
Resveratrol is also an antidiabetic and perhaps the most powerful naturally occurring anti cancer substance. It is proposed that a daily 10mg dose is associated with reduction in insulin resistance in type2 diabetes.
Resveratrol as the latest nutraceutical is so good that drug companies are trying to mimic its molecules!