Resveratrol
(3,5,4'-trihydroxy-trans-stilbene) is a stilbenoid, a type of natural phenol, and a phytoalexin produced naturally by several plants when under attack by pathogens such as bacteria or fungi. Resveratrol is found in the skin of red grapes and in other fruits. However, red wine contains very little of it, on the order of 0.1-14.3 mg/l. Resveratrol has also been produced by chemical synthesis and by biotechnological synthesis (metabolic engineered microorganisms) and is sold as a nutritional supplement derived primarily from Japanese knotweed.
Cardioprotective effects
Moderate drinking of red wine has long been known to reduce the risk of heart disease. This is best known as “the French paradox”.
Studies suggest resveratrol in red wine may play an important role in this phenomenon.
Anti-diabetic effects
Studies have shown resveratrol possesses hypoglycemic and hypolipidemic effects in both streptozotocin (STZ)-induced diabetes rats and STZ-nicotinamide-induced diabetes rats. Resveratrol ameliorates common diabetes symptoms, such as polyphagia, polydipsia, and body weight loss. Other diabetic animal model studies by different researchers have also demonstrated the antidiabetic effects of resveratrol.
Neuroprotective effects
In November 2008, researchers at the Weill Medical College of Cornell University reported dietary supplementation with resveratrol significantly reduced plaque formation in animal brains, a component of Alzheimer's disease and other neurodegenerative diseases. In mice, oral resveratrol produced large reductions in brain plaque in the hypothalamus (−90%), striatum (−89%), and medial cortex (−48%) sections of the brain. In humans, oral doses of resveratrol thoretically may reduce beta amyloid plaque associated with aging changes in the brain. Researchers theorize that one mechanism for plaque eradication is the ability of resveratrol to chelate (bind) copper. The neuroprotective effects have been confirmed in several animal model studies.
Anti-inflammatory effects
The anti-inflammatory effects of resveratrol have been demonstrated in several animal model studies. In a rat model of carrageenan-induced paw edema, resveratrol inhibited both acute and chronic phases of the inflammatory process. Similarly, preincubation with resveratrol decreased arachidonic acid release and COX-2 induction in mouse peritoneal macrophages stimulated with tumor promoter PMA, ROI, or lipopolysaccharides (LPS). In an experimental Rabbit inflammatory arthritis model, resveratrol showed promise as a potential therapy for arthritis. When administered to rabbits with induced inflammatory arthritis, resveratrol protected cartilage against the progression of inflammatory arthritis.