The discovery of the protein, which is called TRAP and which is secreted by immune cells in fat tissue, provides new insights into the chronic fat tissue inflammation that characterises obesity. Using both cell cultures and mice studies, the researchers have shown that TRAP stimulates the formation of new fat cells and can thus precipitate the development of obesity. The results also show that patients with obesity have excessive levels of TRAP.

In malignant obesity, the fat cells are enlarged and less sensitive to insulin, which can lead to high glucose levels and type II diabetes. The scientists were able to show, however, that in mice TRAP gives rise to more benign fat cells of a normal size and metabolism.

“This protein is potentially useful in the treatment of conditions involving morbid cachexia, such as certain cancer diseases,” says Professor Göran Andersson who has led the study with Professor Peter Arner. “The discovery can also lead to new ways pf treating obesity based on the inhibition of this protein’s effect.”

Publication: ‘Monomeric Tartrate Resistant Acid Phosphatase Induces Insulin Sensitive Obesity’, Pernilla Lång, Vanessa van Harmelen, Mikael Rydén, Maria Kaaman, Paolo Parini, Claes Carneheim, A Ian Cassady, David A Hume, Göran Andersson, Peter Arner, PLoS ONE, 5 March 2008.

For further information, please contact:

Professor Göran Andersson
Department of Laboratory Medicine
Tel: +46(0)8 585 81031

Professor Peter Arner
Department of Medicine, Huddinge
Tel: +46 (0)8 585 823 42 or +46 (0)70 579 81 21

Press Officer Katarina Sternudd
Tel: +46 (0)8524 838 95 or +46 (0)70-2243895

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