1. Future Diabetes Treatment May Use Resveratrol to Target the Brain
2. Ethnic Background May Be Associated with Diabetes Risk
3. New Patient Guide to the Endocrine Treatment of Transsexual Persons Available
1. Future Diabetes Treatment May Use Resveratrol to Target the Brain
Resveratrol, a molecule found in red grapes, has been shown to improve diabetes when delivered orally to rodents. Until now, however, little has been known about how these beneficial changes are mediated in the body. A new study accepted for publication in Endocrinology, a journal of The Endocrine Society, shows that the brain plays a key role in mediating resveratrol’s anti-diabetic actions, potentially paving the way for future orally-delivered diabetes medications that target the brain.
Resveratrol activates sirtuins, a class of proteins that are thought to underlie many of the beneficial effects of calorie restriction. Previous studies in mice have provided compelling evidence that when sirtuins are activated by resveratrol, diabetes is improved. Sirtuin activators are now being tested in humans as anti-diabetic compounds.
Sirtuins are expressed virtually everywhere throughout the body and until now, little has been known about what tissues mediate resveratrol’s beneficial effects. Knowing where in the body the beneficial effects of activated sirtuins are mediated could help in the development of more effective targeted diabetes medications.
“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,” said Roberto Coppari, PhD, of the University of Texas Southwestern Medical Center and co-author of the study. “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.”
“These findings may lead to new strategies in the fight against type 2 diabetes,” said 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.”
Other researchers working on the study include Giorgio Ramadori, Laurent Gautron, Teppei Fujikawa, Claudia Vianna and Joel Elmquist of the University of Texas Southwestern Medical Center in Dallas, Tex.
The article, “Central administration of resveratrol improves diet-induced diabetes,” will appear in the December 2009 issue of Endocrinology.
2. Ethnic Background May Be Associated with Diabetes Risk
Fat and muscle mass, as potentially determined by a person’s ethnic background, may contribute to diabetes risk, according to a new study accepted for publication in The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM).
Obesity, a worldwide health concern, is associated with increased insulin resistance, type 2 diabetes and cardiovascular disease. The prevalence of obesity is increasing in all populations across the globe, yet past research has found that body fat distribution varies widely among different ethnic groups. Researchers in this study investigated which ethnic groups were most likely to be at increased risk for diabetes due to higher total body fat and lower muscle mass.
“We know certain ethnic backgrounds show significant differences in amounts of body fat and lean mass,” said Scott Lear, PhD, of Simon Fraser University in Vancouver, Canada and lead author of the study. “What we didn’t know, until now, is if these differences are related to insulin levels and insulin resistance, and therefore lead to an increased risk for diabetes. Our findings indicate they are.”
In this study, researchers measured insulin levels and compared the amount of total body fat to lean mass in 828 men and women of Aboriginal, Chinese, European and South Asian origin to determine how differences in fat mass and lean mass may be related to insulin levels and insulin resistance in each group. Of the four ethnic groups studied, South Asians were found to have both higher fat mass, lower muscle mass and greater insulin levels, placing them at increased risk for insulin resistance and diabetes.
“An individual’s ethnic background may determine the amount of body fat and lean mass they have, and therefore may also be associated with diabetes risk,” said Lear. “In populations at increased risk for diabetes, interventions that reduce fat mass and increase muscle mass, such as caloric restriction and regular exercise should be investigated.”
Other researchers working on the study include Simi Kohli of Simon Fraser University in British Columbia, Canada; Gregory Bondy of the University of British Columbia in Canada; Andre Tchernof of Laval University Medical Research Centre in Laval, Canada; and Allan Sniderman of McGill Health Science Centre in Montreal, Canada.
The article, “Ethnic variation in fat and lean body mass and the association with insulin resistance,” will appear in the December 2009 issue of JCEM.
3. New Patient Guide to the Endocrine Treatment of Transsexual Persons Available
The Hormone Foundation has recently published a new patient guide to the endocrine treatment of transsexual persons. The guide defines gender identity disorder (GID) and describes the two main aims of hormone therapy for individuals with GID: to suppress the production of hormones that are determined by the person’s biologic sex, and to maintain “cross-sex” hormone levels within the normal range for the person’s desired, opposite gender. It stipulates that persons with GID must first be diagnosed with the condition by a mental health professional and live full-time in the desired gender role for one year. The guide then describes appropriate endocrine therapy for adolescents and adults with GID. For more information visit: www.hormone.org.
