Study raises hope for obesity treatment

By Julie Steenhuysen

CHICAGO (Reuters) - U.S. researchers may have found an obesity treatment that unlocks the fat-fighting promise of leptin, an appetite-suppressing hormone once hailed as the answer to the battle of the bulge.

The problem with leptin is that it loses its power in obese people, but a team at Harvard Medical School may have found a way around that problem, they reported on Tuesday.

They said fat mice treated with two drugs already approved for use in humans overcame leptin resistance, raising hopes once again for leptin as a treatment for obesity.

“We are very excited to see what will happen in humans,” said Dr. Umut Ozcan of Children’s Hospital Boston and Harvard Medical School, whose study appears in the journal Cell Metabolism.

“If it works, this can be a treatment for obesity,” Ozcan said in a telephone interview.

The discovery of leptin in 1995 raised hopes for a natural weight loss tonic. Obese mice that lacked leptin lost weight on the stuff. But in obese humans, leptin only brought temporary success.

Ozcan said most people who are obese develop leptin resistance, in which the brain stops responding to the hormone’s message to stop eating.

His team found that brain cells of obese mice have increased stress in the endoplasmic reticulum or ER — a structure within the cells where proteins are assembled.

In obesity, this structure becomes overwhelmed and stops working properly, and begins to block incoming chemical signals.

“This organelle gets stressed or angry. It starts to send signals to say, ‘Look, I’m exhausted.’ These signals are called unfolded protein response,” Ozcan said.

After showing that this stress blocks the leptin response, Ozcan’s team set about trying re-sensitize the brain to leptin by reducing the ER stress.

The researchers tried two existing drugs — 4-phenyl butyric acid or PBA, which treats cystic fibrosis, and tauroursodeoxycholic acid or TUDCA, which treats a liver disease. Both act as ER stress reducers.

First they gave either of the two drugs to obese mice fed a high-fat diet, then injected them with leptin. “We have seen significant weight loss in these mice,” Ozcan said.

“Reduction of ER stress makes the mice sensitive to the leptin, which is bringing new hope for the treatment of obesity,” he said.

The next step is to try the drugs in humans.  Continued…


Related Posts:

Are you one of those people who swears you can’t lose weight no matter what? Have you ever said “It’s not my fault, if I even look at food I gain weight”? Do you wish you could just flip a switch and make your metabolism go back to the way it worked when you were 20? At long

Full Post: This Hormone May Be the Reason You Are Fat

By Will Dunham WASHINGTON (Reuters) - Scientists have identified a fatty substance made in the gut that signals the brain when it’s time to stop eating — a discovery that could inspire new approaches to fighting obesity. Writing in the journal Cell on Wednesday, U.S. researchers said experiments with mice and rats showed that a naturally occurring

Full Post: Gut chemical may inspire new way to fight obesity

By Will Dunham WASHINGTON (Reuters) - A study involving chocolate milkshakes is helping scientists get a better understanding of how the brain influences obesity, with genes playing a role, too. Obese people may get less satisfaction from food due to a blunted response in brain circuitry relating to pleasure, and may overeat to make up for the

Full Post: Milkshake study reveals brain’s role in obesity

By Julie Steenhuysen CHICAGO (Reuters) - Leukemia cells use powerful chemical signals to lure healthy blood-forming stem cells into their cancerous lairs, where they lose their power to make healthy blood cells, U.S. researchers said on Thursday. But by jamming these signals in mice, the team was able to protect the stem cells, called hematopoietic progenitor cells. If

Full Post: Fatal attraction: How leukemia seduces blood cells

By Martina Fuchs LONDON (Reuters) - A breakdown in a reaction between immune cells and blood vessels in the brain appears to play a key role in epilepsy, Italian researchers said Monday. The discovery could mean that some modern antibody-based drugs designed to modify the immune system used in other diseases may one day help fight the

Full Post: Scientists shed light on causes of epilepsy

Site Navigation

Most Read