Obesity Regulation

The quicktake home here is that adiponectin is involved directly with the establishmentof the dangerous abdominal fat associated with Cardio issues.

Theinteresting question to answer is why does the hormone level fail to increasewith increasing body fat?  It is all agood argument for using alternate day fasts (Google 'arclein diet') to bring one’s weight to its bestbase level.  At base level such ahormonal system should be optimized in terms of their benefit which issomething that seems likely anyway.

This may leadto a clear understanding of the pathways that support outright obesity.

Released: 12/23/2010

Newswise — New findingsby UT Southwestern Medical Centerresearchers may solve a 17-year-old mystery about how the so-called “starvationhormone” affects multiple biological systems, including preventing insulinsensitivity and promoting cell survival.

The results connectmultiple observations about how the hormone adiponectin functions andeventually could lead to new treatments for conditions ranging from diabetesand weight loss to heart disease and cancer.

“Until now, therewasn’t really an obvious connection between all these different phenomena,”said Dr. Philipp Scherer, professor of internal medicine and cell biology andsenior author of the study appearing online today and in a future edition of Nature Medicine.

In this study, theresearchers used models of inducible cell suicide in both pancreatic betacells, which produce insulin, and cardiomyocytes, which are specific musclecells located in a part of the heart known as the myocardium, to determine howthe single hormone could exert such different influences.

“This paper shows thatthe common theme among all these different activities relies on adiponectin’sinteraction with a specific subset of lipids known as ceramides,” said Dr.Scherer, who directs the Touchstone Center for Diabetes Research.

Ceramides are a familyof lipid molecules known to promote cell suicide, or apoptosis. High levels ofceramides have been shown to promote diabetes by sabotaging signaling pathwaysinduced by insulin and killing beta cells.

When the researchers introducedadiponectin into cells, they found that the hormone triggers the conversion ofceramides from a destructive force into one that helps cells survive andinhibits cell death.

“Adiponectinessentially provides a makeover of this ugly cousin,” Dr. Scherer said.
Dr. William Holland,lead author and postdoctoral fellow in internal medicine, said the new findingshave implications for the treatment of numerous diseases including diabetes andcancer.

“One beauty of thisstudy is that the findings are in both animal models and in vitro,” Dr. Hollandsaid. “We were able to show using these models of apoptosis in the beta celland the heart that we can protect those cells from cell death withadiponectin.”

Adiponectin, which Dr.Scherer discovered in 1994, not only controls sensitivity to insulin but alsois known to play an integral role in metabolism and obesity. Prior research hasshown that when adiponectin levels are high, the body stores excess fat inadipocytes, or fat cells, to protect against possible starvation during leantimes. These fat deposits lie primarily in the subcutaneous tissue.

As a person accumulatesmore fat, however, adiponectin levels decline. Once adiponectin levels startdropping, the body begins storing fat in dangerous places such as the heart,liver and muscle tissues – where it can cause inflammation and pave the way forheart disease. That’s why researchers think that adiponectin levels could be agood predictor of whether someone is at risk of developing diabetes, heartdisease or cancer.

Overall, the newfindings “endorse the idea that adiponectin is very important and is probably akey manipulator of lipid levels,” Dr. Scherer said.

Other UT Southwesternresearchers involved in the study include Drs. Kai Sun, Joseph Rutkowski, ZhaoWang and Kathryn Davis, postdoctoral research fellows in internal medicine;Vincent Tenorio, summer student research fellow; and Dr. Nils Halberg, formerpostdoctoral research fellow in internal medicine. Researchers from the University of Pennsylvania,Eli Lilly, Duke UniversityMedical Center,Duke-NUS Graduate Medical School Singapore, ColoradoState University,the University of Copenhagen and MerckResearch Laboratories also contributed to the study.

The study was supportedby the National Institutes of Health. 

This news release isavailable on our World Wide Web home page at

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