Leptin!

[bigrand]

Leptin Downregulates Specific Liver Enzyme Causing Leanness, Hypermetabolism




NEW YORK (Reuters Health) Jul 12 - Scientists at The Rockefeller University in New York report that they have identified a specific hepatic enzyme that is downregulated by the leptin gene, which leads to leaner animals that have more energy expenditure.
Suppression of RNA synthesis of hepatic stearoyl-CoA desaturase-1 (SCD-1) resulted in the changes, according to the report in the July 12th issue of Science by Dr. Jeffrey M. Friedman and colleagues at Rockefeller and at the University of Wisconsin, Madison.

The team found that found that leptin-deficient (ob/ob) mice who were also deficient in SCD-1 had a 40% reduction in body mass and a 75% increase in energy expenditure compared with ob/ob controls who did not have a decreased expression of the SCD-1 gene. The SCD-1 deficient mice had very low triglyceride and VLDL cholesterol production and livers that were histologically normal.

Dr. Friedman notes that the metabolic effects of leptin cannot be explained by food intake alone, as the findings published today show. "These data show that SCD-1 is required for the fully developed obese phenotype of ob/ob mice and suggest that a significant proportion of leptin's metabolic effects may result from inhibition of this enzyme."

The investigators speculate that downregulation of the SCD-1 enzyme reduces fatty acid biosynthesis by reducing intracellular malonyl CoA and is also accompanied by an increase in fatty acid oxidation.

Science 2002;297:240-243.



I like the 75% increase in energy expenditure and 40% loss in mass. Leptin is a very interesting topic to me. Anyone know of any good info on how to manipulate it?

 

[bigrand]

Doesnt Bromo do something with it?

 

[georgie24]

how much does bromo go for?

 

[serge]

love the post, where did you dig it up?

 

[bigrand]

It was a very recent study sent to me from medscape.
I dont know much about Bromo, other than i heard it can act on Leptin somehow?

 

[bigrand]

Bromo?
Vitex?

 

[drveejay11]

Bumparoni! I would like to see some more info on this !

 

[drveejay11]

Here's a nice intro fellas:

Look

 

[drveejay11]

For you lazy bastards:

Leptin, a hormone-like messenger protein (known technically as a cytokine), is produced in relatively large amounts by fat tissue and in smaller amounts by other peripheral organs, and then secreted into the bloodstream, where it travels to the brain and other tissues, causing fat loss and decreased appetite. Once leptin has been secreted by your fat cells, it travels to the hypothalamus-the part of your brain that has an influence on eating behavior.

In the medial hypothalamus, leptin activates "anorectic" nerve cells, which serve to suppress your appetite.

At the same time, leptin prevents "orexigenic" cells from stimulating your appetite.

Leptin (from the Greek leptos, meaning thin) first came to national attention in 1994 when the obesity gene and its product leptin were discovered.

It was shown then that obese mice dropped 40 percent of their body weight after only one month of treatment with leptin.

Leptin also improved symptoms of diabetes. Recently, the taste organ was found to be one of the peripheral targets for leptin. The hormone specifically inhibits sweet taste responses in lean mice. Thus, leptin appears to act as a modulator of sweet taste.

Leptin also suppresses a gene that produces an enzyme known as acetyl-CoA carboxylase, or ACC, which is essential for fat production.


When researchers injected laboratory mice with leptin, previously obese mice became as thin as rodent track stars!

(Left) Mouse with defective ob gene lacks the OB protein (leptin), which regulates the body, signaling the amount of fat stored. (Right) Mouse treated with leptin shed 40 percent of its body weight. Both of these mice have a defect in a gene called obese (ob). This mutation usually results in a marked increase in the amount of fat.

Administration of the protein encoded by the ob gene, called leptin, reduced the body weight of the ob mice.

After four and a half weeks, the ob mouse on the left, which did not receive leptin, weighed approximately 67 grams while the mouse on the right, who received daily injections of leptin, weighed 35 grams. Normal mice weigh approximately 24 grams, a weight equivalent to that of an orange.

Daily injections of leptin to ob mice reduced body weight via effects on food intake and energy expenditure, meaning the treated animals ate less and also burned more calories.

Some researchers believe that leptin works, in part, by inhibiting the synthesis of fat in fat cells and increasing the burning of fat in muscle cells-that it works at an enzymatic cellular level.

Copyright © 2002 - ITG Inc. All Rights Reserved
ImmuneTree 1-888-484-8671

Karma anyone?

 

[georgie24]

FONZ--?--?