New drug target in obesity: Fat cells make lots of melanin

As millions of Americans gear up for the Thanksgiving holiday, a new research report published online in The FASEB Journal, may provide some relief for those leery of having a second helping. In the report, researchers describe a discovery that may allow some obese people avoid common obesity-related metabolic problems without actually losing weight: they make a common antioxidant, melanin, in excess. Even more promising is that some of the antioxidant drugs that can mimic the melanin effect are FDA-approved and available. This availability would greatly speed the development of new treatments, should they prove effective in clinical trials.

The researchers made the unexpected discovery-fat cells in obese people produce melanin in excess-when they were comparing fat cells of obese people to those of people with normal weight. After the comparison, they found that the gene responsible for making melanin was working in "overdrive" in the fat cells of obese people. The finding was then confirmed using additional laboratory tests. Melanin is a common antioxidant responsible for skin and eye color.

Ancha Baranova, one of the study's researchers from George Mason University and INOVA Fairfax Hospital says, "Most scientific efforts aim at making obese individuals lose weight, but this has proven difficult. Hopefully, this study will lead to a drug that keeps obese individuals healthy, reducing the cost-burden to society as well as some of the stigma associated with this condition."

According to the U.S. Centers for Disease Control and Prevention, the prevalence of obesity in 2005– was about 1 in 3 for men and women. Obesity increases the risk of diseases and health conditions, such as high blood pressure, osteoarthritis, dyslipidemia, Type 2 diabetes, coronary heart disease, stroke, gallbladder disease, sleep apnea and respiratory problems, and some cancers.

"No pill can replace a healthy diet and exercise, yet," said Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal, "but this could be a major advance for physicians looking for a safe drug target in their search to keep obese patients healthy while their weight becomes normal."

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This research report will appear in the March 2009 print issue of The FASEB Journal.

Article Details:

Manpreet Randhawa, Tom Huff, Julio C. Valencia, Zobair Younossi, Vikas Chandhoke, Vincent J. Hearing, and Ancha Baranova. Evidence for the ectopic synthesis of melanin in human adipose tissue. FASEB J. first published on October 29, 2008 as doi:10.1096/fj.08-116327.

The FASEB Journal is published by the Federation of American Societies for Experimental Biology (FASEB) and is the most cited biology journal worldwide, according to the Institute for Scientific Information. FASEB comprises 21 nonprofit societies with more than 80,000 members, making it the largest coalition of biomedical research associations in the United States. FASEB advances biological science through collaborative advocacy for research policies that promote scientific progress and education and lead to improvements in human health.