Study grant to open new door for antioxidants in role of lessening CVD risk in diabetic young women
Type 1 diabetes, once referred to as ‘juvenile diabetes’ because that’s the time of life when it is typically diagnosed, has many deleterious effects. The disease which is a chronic condition in which the pancreas produces little or no insulin. Insulin is a hormone needed to allow sugar (glucose) to enter cells to produce energy.
One aspect of the disease often overlooked is the way in which it can increase cardiovascular disease risk among younger women. The members of this population not affected by diabetes enjoy a protective effect from estrogen in their systems. But for type 1 young women, the reverse is true. Epidemiological data indicates women with type 1 diabetes have 2-3 times greater risk of cardiovascular disease than men with type 1.
Antioxidants to the rescue
As a category antioxidants are among the oldest dietary ingredients in the industry and were among its first media stars. Early enthusiasm for the ingredients among the mainstream press as a kind of magic bullet, conferring longevity and resistance to disease, then turned to disillusionment when subsequent experimental results failed to support these overblown claims.
In the years since researchers like Ryan Harris, PhD, associate professor at Augusta University, have looked for more focused mechanisms of action for dietary antioxidants beyond acting as mere free radical sponges, though that continues to be an important aspect of their function.
“My career has been associated with the assessment of vascular function. In about 2012 we started looking at antioxidants and their potential role in vascular function in the presence of diabetes,” Harris told NutraIngredients-USA.
Howard is leading a team at the Medical College of Georgia at Augusta University to look into how antioxidants can affect the vascular health of these type 1 young women. The study is funded by a $3.3 million grant from the National Institutes of Health. Howard, who is associated with the Georgia Prevention Institute and Department of Population Health Sciences, specializes in vascular physiology.
Diabetes turns estrogen on its head
Estrogen seems to be key in the early, rapid aging of the cardiovascular system of type 1 young women. Harris’ team has early evidence that in diabetes the sex hormone estrogen produces a double whammy that increases levels of damaging oxidative stress while dramatically decreasing blood vessels’ ability to dilate.
“When you have diabetes, estrogen turns into a bad guy,” Harris said. “It actually causes blood vessel constriction when you have high levels of estrogen.”
Even isolated in a dish, when you put estrogen on a blood vessel, it dilates, and when you put it on a diabetic blood vessel, it contracts.
“The whole point of the grant is to determine why this happens and what we can do about it,” said Harris.
Harris’s study will consist of 90 premenopausal women with type 1 diabetes, and for comparison sake, 30 healthy premenopausal women and 45 demographically matched men with type 1, all ages 18-40 and without diagnosed cardiovascular disease or other known complications of diabetes.
The study will look at two interventions. One is a well-established ‘antioxidant cocktail’ consisting of vitamins C and E along with alpha lipoic acid. While antioxidant therapy for a wide range of ills has gotten mixed results, Harris said his team has documented their cocktail’s impact in aging adults and COPD and they have early evidence it also works in these women.
The other intervention is resveratrol, which Harris said works on a different pathway by activation the protein Sirt1. Sirt1 lowers the reactive oxygen species produced by the endothelial cells that line blood vessels and increases the availability of nitric oxide, a powerful natural dilator of blood vessels. Levels of Sirt1 naturally increase in the high-estrogen days of the cycle, but Harris said his team has preliminary evidence that diabetes decreases that healthy increase.
“We are really interested in these sirtuin pathways,” Harris said. Other ingredients that might be of interest in this kind of intervention include beetroot extracts and pterostilbene, he said.
Harris said the study, which has just enrolled its first subject, is expected to take five years to complete.