Resveratrol in grapes could protect from diabetes
New research shows that rats fed high fat diets experienced lower insulin levels when scientists injected resveratrol from grapes directly into their brains. The findings suggest that resveratrol could be developed to target specific brain proteins, in turn offering some protection against diabetes in humans.
The findings come from UT Southwestern Medical Center researchers Dr. Roberto Coppari, along with Drs. Giorgio Ramadori, Laurent Gautron and colleagues. According to Dr. Coppari, “These animals were overrun with fat and many of their organs were inflamed. But when we delivered resveratrol in the brain, it alleviated inflammation in the brain.”
Past studies have shown that resveratrol can mediate inflammation that leads to major illness and chronic diseases. Research published this year even suggested that the compound found in red grapes and wine could be developed to treat major illnesses, including widespread systemic infection (sepsis). Researchers have been studying the health benefits of resveratrol for years.
The scientists specifically looked for the effect of resveratrol of a group of proteins in the body called a sirtuins. They wanted to see whether the compound exerted its effect on sirtuins in the brain. Sirtuins help cells survive, and have been linked in the past the anti-aging potential of resveratrol, and also associated with the benefits of calorie restriction. Sirtuin activating drugs are currently being studied for diabetes treatment.
However, the authors of this study say consuming products made from red grapes and drinking too much red wine will not protect from diabetes. According to Dr. Coppari, “The main reason is that resveratrol does not cross the blood brain barrier efficiently,” he said. “In order for the brain to accumulate the same dose of resveratrol delivered in our study, the amounts of red wine needed daily would surely cause deleterious effects, especially in the liver. Rather, our study suggests that resveratrol’s analogs that selectively target the brain may help in the fight against diet-induced diabetes.”
Rats fed a high fat diet before and after the study either received resveratrol directly injected into the brain, or a saline solution. Insulin levels rose in the placebo group. Five weeks into the study, the rats injected with the compound found in red grapes and wine, and despite continuing with a high fat diet, had insulin levels that were halfway to normal – they also found that resveratrol does activate sirtuin.
Knowing how resveratrol works in the brain could interest pharmaceutical companies in developing drugs that target sirtuins in the brain. The researchers say the brain is an important mediator of the beneficial effects of resveratrol found in red wine and grapes. You can find a variety of studies about potential benefits of resveratrol here.