Washington: Scientists claim to finally have found a link between obesity and diabetes – inflammation -causing cells in fatty tissue cause insulin resistance.
An international team, led by University of New South Wales, has found the link, which it claims may pave the way for new anti-inflammatory treatments which prevent insulin
resistance and other complications associated with obesity.
"We have shown that insulin resistance in human obesity is closely related to the presence of inflammatory cells in fat tissue, in particular a population of macrophage
cells," Prof Len Harrison, who led the team, said.
Macrophages, white blood cells derived from the bone marrow, are immune cells that normally respond to infections.
In obese people, macrophages move into the fat tissue where they cause inflammation and release cytokines, which are chemical messenger molecules used by all the immune cells to communicate. Certain cytokines cause cells to become resistant to the effects of the hormone insulin, leading to diabetes.
The scientists have based their findings on an analysis of the fat tissue of more than 100 people who had undergone lapband surgery.
The findings provide the first evidence in humans that macrophages in fat tissue are producing cytokines that prevent cells from appropriately responding to presence of insulin, say the scientists.
"The complications of obesity such as insulin resistance and diabetes, cardiovascular disease associated with hardening of the arteries, and liver problems are the
result of inflammation that occurs in the fat tissue.
"These complications could be prevented by developing drugs that target certain cytokines released by the macrophages.
"Encouragingly, our study also showed that when obese people lost weight the macrophages in the fat tissue disappeared, as did the risk of developing insulin resistance
and diabetes," Prof Harrison said.
The findings have been published in the latest edition of the `Diabetes` journal.