An inflammatory factor already linked to several diseases, including pulmonary disease, lung cancer, and arthritis, may also be responsible for the insulin resistance that comes with obesity, according to a new study.

Researchers have found that the inflammatory chemokine known as CXCL5 rises and falls along with obesity and weight loss in humans. They also found evidence tying the inflammatory factor, which is secreted at high levels by fat tissue, to insulin resistance in mice.

Treatments designed to block CXCL5 were found to improve the animals' sensitivity to insulin.

CXCR5 affect a variety of cells including muscle cells, cells that line blood vessel walls and cells in the lung and intestine. This means that increased CXCL5 circulating levels, as observed in obesity, could also lead to other problems such as atherosclerosis and other inflammatory diseases.