DURHAM, N.C. – The link between obesity and osteoarthritis may be more than just the wear and tear on the skeleton caused by added weight.
A Duke University study has found that the absence of the appetite hormone leptin can determine whether obese mice experience arthritis, no matter how heavy they are.
“We were completely surprised to find that mice that became extremely obese had no arthritis if their bodies didn’t have leptin,” said Farshid Guilak, Ph.D., director of orthopaedic research in the Duke Department of Surgery. “Although there was some earlier evidence that leptin might be involved in the arthritis disease process, we didn’t think that there would be no arthritis at all.”
In fact, the joints from the obese mice in the study appearing in the journal Arthritis & Rheumatism looked better than those of the normal control mice, Guilak said. “However, in another study, we found that mice that gained half as much weight on a high-fat diet but processed leptin normally showed significant knee osteoarthritis.”