By Merritt McKinney

NEW YORK, Jan 31 (Reuters Health) - An experimental compound that mimics the hormone insulin keeps mice from gaining too much weight, researchers report.

The natural way to lose weight is to eat less and exercise more, but as more and more Americans become overweight and obese, researchers have been searching for drug therapies to use in the battle of the bulge.

Insulin has become a focus of this research, because animals eat less and lose weight after the sugar-regulating hormone is injected into the brain. But when given systemically, insulin can lead to weight gain.

A team of researchers led by Dr. Bei. B. Zhang, of Merck Research Laboratories in Rahway, New Jersey, may have found a way around the problems of using insulin to fight obesity.

Zhang's team found that compounds that simulate the effects of insulin can keep mice from becoming obese. The findings are published in the February issue of the journal Nature Medicine.

When injected into the brains of mice, the insulin-like compounds caused the mice to eat less and lose weight. Of course, an anti-obesity treatment that must be injected into the head is not very practical, so Zhang and her colleagues tested a form of insulin-mimicking compound that can be taken orally. Normal insulin cannot be given orally.

The researchers tested the compound in mice that were on a high-fat diet. Not surprisingly, mice that did not receive the compound rapidly gained weight while on this diet.

In contrast, mice that were on the high-fat diet but that had the compound mixed into their food gained weight much more slowly. The speed of their weight gain was similar to that of mice on a normal diet.

The treatment prevented not only obesity, but some of its harmful health effects, including high blood sugar and insulin resistance--a precursor to full-fledged diabetes in which the body becomes less responsive to insulin.

As far as the researchers could tell, the treatment did not cause any side effects.

Zhang and her colleagues are not sure how the insulin-like compounds work to prevent obesity. Since people who take insulin to treat diabetes often gain weight, treatment with a similar molecule would be expected to cause weight gain, they note.

"Contrary to this, however, it had the opposite effect," the authors state.

The results "provide proof-of-principle for a novel approach for the treatment of obesity and related metabolic disorders," Zhang's team concludes.

According to Janet Skidmore, a spokeswoman for Merck, the research shows "real promise." She stressed in an interview, however, that "we are a long way" from the development of an anti-obesity drug.

The findings "suggest that there are some important implications but that it's important for us to know that this is basic research," Skidmore said.

SOURCE: Nature Medicine 2002;8:179-183.

http://www.reutershealth.com/archiv...131elin016.html

Interesting, Doreen.

A lot of these hormones are extremely unstable. FMS (Fat mobilizing substance) for example is oxidised by sunlight, and has to be kept in darkened glass, and it can be easily broken down by a number of substances and ordinary processes. So I imagine one part of the research will involve ways of stabilising this new hormone for practical use. Another may be elimination of impurities. There will be many practicalities and logistics to overcome, but these initial results do sound exciting.

Andy

It said the mice were fed a high fat diet to gain weight. Perhaps they meant the mice were fed a high carb/high fat diet to gain weight. I don't think the mice would have gained on a diet of pure fat.


Elihnig

Yes, Beth ... I was thinking the same thing. But you know, researchers have a blind eye when it comes to carbs ... If a french fry or donut is placed before them, they only see the fat.



Doreen