Henry and thread,
some leptin related news...
LONDON, May 6 (Reuters) - Danish scientists said on Wednesday that a protein in the brain of fat rats that regulates appetite could be a key element in controlling obesity in humans.
Peter Kristensen, a pharmacologist with Danish bio-tech group Novo Nordisk, said a brain protein called CART cocaine-and amphetamine-regulated transcript) produces a full feeling in rats and probably works the same way in humans.
''CART is a protein which is made in the brain and is involved in satiety. It's a protein that mediates fullness,'' Kristensen said in a telephone interview.
Scientists already know that the hormone leptin, which is produced by fat cells and found in abundance in obese people and mice, regulates food intake and body weight but they were not sure how.
Kristensen and his colleagues have shown that CART acts with leptin inside the brain to suppress appetite to produce a full feeling. Another brain compound called neuropeptide Y (NPY) has the opposite effect. It works with leptin to increase feeding in animals.
So far Kristensen has only tested the theory on rats but he said he was confident that CART would have a similar function in humans.
''These are very basic mechanisms. It's the same protein in humans. By creating a drug that works like CART you could make a pill that would make you feel less hungry. It's certainly a step in terms of identifying and treating obesity,'' he added.
In his study of obese rats, reported in the scientific journal Nature, Kristensen found that all the rodents had very low levels of CART.
When he injected antibodies against CART in normal mice it increased and prolonged their feeding. He found that any disruption of either leptin levels or the leptin receptor led to decreased amounts of CART, and a reverse relationship existed for NPY.
''NPY and CART may thus be two of the factors that balance the effects of leptin on feeding through the hypothalamus (area of the brain),'' Kristensen said.
''We propose that leptin-mediated suppression of food intake is controlled by a balanced reduction and induction of NPY and CART, respectively.''
Kristensen and his team are now trying to isolate other targets in the brain that are influenced by CART with the intention of developing new therapies for obesity.
Regards,
Steve |
