Red wine compound slows brain plaque linked to Alzheimer's disease, study finds.

Feng Y, X Wang, S Yang, Y Wang, X Zhang, X Du, X Sun, M Zhao, L Huang and R Liu. 2009. Resveratrol inhibits beta-amyloid oligomeric cytotoxicity but does not prevent oligomer formation. Neurotoxicology doi: 10.1016/j.neuro.2009.08.013.

Resveratrol is a compound that is generating a lot of health buzz, and not just because it is found in red wine. Results from a newly published laboratory study show the compound may slow the development of protein clumps – called amyloid fibrils. The fibrils – made of beta-amyloid protein – ultimately aggregate into the distinctive plaques commonly found in Alzheimer’s patients.

Alzheimer's disease is a form of dementia that robs people of their ability to remember and perform simple tasks, such as eating and dressing. There are no known medications to ease or cure this debilitating and fatal disease.

Preventing the formation of fibrils and untangling them once they aggregate into plaques are the current focus of efforts to combat this illness that attacks brain tissue. As many as 5.3 million people in the United States live with the disease, according to the Alzheimer's Association.

The findings from the study, which was recently published online in the journal Neurotoxicology, agree with prior human epidemiology studies that associate frequent red wine consumption with a reduced risk of developing dementia. Resveratrol – and other similar compounds called polyphenols – have long been thought to contribute to this beneficial effect. Resveratrol is a potent antioxidant that is also associated with numerous other health effects, including a reduced risk of cardiovascular disease.

Researchers tested resveratrol's effects on fibrils by combining one type of beta-amyloid (Aβ42) with it and then looking for protein aggregation. They found that the higher the dose of resveratrol, the lower the amount of aggregation. Resveratrol reduced the aggregation by as much as 90 percent.

Resveratrol also induced the beta-amyloid fibrils to come apart, suggesting it may have the potential to wipe out plaque that has already formed.

Although amyloid plaques are a distinctive feature of Alzheimer’s disease, it is not yet clear how these plaques cause the dementia associated with the disorder. There is some suspicion that the fibrils that accumulate into the distinctive plaques are less toxic to the brain than the intermediate compounds called oligomers. Unfortunately, resveratrol did not reduce the formation of oligomers, although the researchers found some evidence that resveratrol could reduce their toxic impact to cells.

This study was conducted in the laboratory and not in live animals or people. The amounts of resveratrol used for this study, and in others that report its health benefits, are higher than levels would be after drinking red wine. Future studies are necessary to determine if drinking or eating resveratrol – either through a normal diet or through supplements – could reduce plaque formation in the brain, rather than just in a test tube.