Resveratrol, an antioxidant molecule found in red grapes and other dark coloured fruit such as blueberries, has been shown to improve diabetes when given orally to rats and mice. However, however, little has been known about how or where these beneficial changes actually occur in the body.
Researchers at the University of Texas Southwestern Medical Center may have found the answer.
Their results, showing that the brain plays a key role in mediating resveratrol’s anti-diabetic actions, have been accepted for publication in the December 2009 issue of Endocrinology, a journal of The Endocrine Society
Resveratrol’s Action Controlled by Brain
Resveratrol, a polyphenol antioxidant found in red wine and red grapes, is also a component of pomegranates, blueberry, olive leaf and other ‘wonder foods’ believed to reduce oxidative stress from free radicals. As well as being touted as an anti-ageing compound, reseveratrol is being considered for its anti-diabetic action.
Lead researcher of the University of Texas team, Dr Roberto Coppari, said they hypothesised that the brain could be the organ mediating resveratrol’s anti-diabetic actions by activating sirtuins.
Surtuins are a class of proteins that are thought to underlie many of the beneficial effects of calorie restriction. Previous studies in mice have shown that when sirtuins are activated by resveratrol, their induced Type 2 diabetes is improved.
Sirtuins are found in all tissues of the mammalian body, including the brain, and it has been unclear where resveratrol’s beneficial effects were happening.
Targeting Resveratrol to be Effective
“We know that sirtuins are expressed in parts of the brain known to govern glucose metabolism, so we hypothesized that the brain could be mediating resveratrol’s anti-diabetic actions,” Dr Coppari said.
“To test the hypothesis, we assessed the metabolic consequences of delivering resveratrol directly into the brain of diabetic mice. We found that resveratrol did activate sirtuins in the brain of these mice which resulted in improving their high levels of blood sugar and insulin.”
Now that the centre of resveratrol’s action is known, shouldn’t people just consume more fruits containing the compound?
Not so, according to Australian nutritional scientist Christine Houghton, who says that that the amount of the substance the body can obtain from fruit or wine is a tiny percentage of what the fruit contains, and that most of that is destroyed in the digestive process.
She is backed up by University of Queensland Professor of Pharmacology, Dr Steven Taylor. However, Dr Taylor, does advocate getting some resveratrol from enjoying a good red wine.
"Absorption via the mucous membranes in the mouth can result in up to around 100 times the blood levels (from eating fruit), if done slowly rather than simply gulping it down,” he said.
New Diabetes Medications to Mimic Resveratrol?
The University of Texas researchers suggest that directly targeting the brain would be the most effective method in treating Type 2 diabetes. “These findings may lead to new strategies in the fight against type 2 diabetes,” said Dr Coppari.
“By knowing that the brain mediates resveratrol’s anti-diabetic actions, industry can now focus on developing sirtuin activators that directly target the brain. When orally-delivered, these drugs will likely improve diabetes without affecting the other organs in which activation of sirtuins may not always be beneficial.”
You might also be interested in Resveratrol – Not Enough In Red Wine To Be Effective andDiabetic Benefits of Black Tea.
Sue Cartledge - I'm a science, health, nutrition and lifestyle journalist, fascinated by the way the physical world operates in all its forms, and how ...
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