A new study has discovered the potential beneficial effects of high doses of resveratrol in fighting the age-related Alzheimer's disease.
Researchers from Georgetown University conducted a year-long experiment to test the effects of resveratrol in its purified form and saw that long-term intake of high doses by people with Alzheimer's—whether mild or moderate—led to the stabilization of amyloid-beta40 (Abeta40), a biomarker that declines as the disease progresses.
For the study, the researchers monitored 119 patients diagnosed with mild to moderate Alzheimer's disease and gave each participant either resveratrol or a placebo each day for a whole year. Results were published in the journal Neurology.
While resveratrol cannot be recommended by the findings of the said research alone, the experiment showed some very interesting results, said R. Scott Turner, M.D., Ph.D., Georgetown University Medical Center's Memory Disorders Program director and principal investigator of the study.
In the experiment, the participants who received resveratrol were orally given the highest dose: one gram, two times a day. Resveratrol is also commonly found in the peel of grapes and in dark chocolate and red wine. The daily high dose that the participants were given was equivalent to about a thousand bottles of red wine.
Among the patients who received high doses of resveratrol, the researchers found that after 12 months, there was very little—or none at all—change in Abeta40 in the blood stream or cerebrospinal fluids. In those who took a placebo, on the other hand, the levels of Abeta40 decreased, lower than their levels measured at the beginning of the experiment.
Turner explained that Abeta40 decreases as dementia or Alzheimer's progresses, but he also noted that their study alone cannot be the sole basis of the beneficial effects of resveratrol. By measuring resveratrol in both the cerebrospinal fluid and in the blood, the researchers noticed that resveratrol penetrated the blood brain barrier. For Turner, this observation is an important finding.
Resveratrol is an activator of proteins called sirtuins, which are also activated by caloric restriction. Experiments on animals have revealed that caloric restriction prevents or delays common age-related diseases, such as Alzheimer's disease. Common side effects seen in participants who were given resveratrol were gastrointestinal-related, such as nausea and diarrhea, and weight loss.
"This is a single, small study with findings that call for further research to interpret properly," said Turner.
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