Delivering the hormone leptin directly to the brain through gene therapy aids weight loss without the significant side effect of bone loss, according to new collaborative research from Oregon State University and University of Florida.
Rapid or significant weight loss through dieting can trigger bone loss. Loss of bone density, in turn, can lead to increased susceptibility to bone fractures in older adults, which can have a debilitating effect on quality of life.
The bone loss is most concerning in people whose weight fluctuates due to “yo-yo” dieting, or repeated cycles of weight gain and loss, because bone lost during weight loss is not typically regained when the person gains weight again, said Dr. Urszula Iwaniec, an associate professor in the College of Public Health and Human Sciences at OSU.
“Weight loss is generally good for you if you are seriously overweight, but bone loss can cause significant problems later in life,” said Dr. Iwaniec, whose research focuses on metabolic bone disease and bone health. “What we are trying to determine is whether there is a way to lose excessive weight while preserving bone density.”
In the study, rats who received leptin had a weight reduction of about 20 percent, but they did not have any bone loss. The rats that lost weight were able to maintain that weight loss. They also had large reductions of abdominal fat, also known as “bad” fat, which is known to contribute to weight-related health problems.
The findings were published this week in the Journal of Endocrinology. Co-authors of the paper included Dr. Russell Turner, director of OSU’s Skeletal Biology Lab, and several Oregon State University faculty, as well as researchers from the University of Florida. The study was supported by grants from the National Institutes of Health and the Department of Defense.