Weight Reduction By Injecting A Therapeutic Gene

 Credit: Yong-Hee Kim
A team of researchers has developed a technique for delivering a therapeutic gene to fat cells, causing the fat cells to function less efficiently, thereby reducing weight in test mice. In their paper published in Nature Materials, the team describes how they developed their technique, their results and problems they have yet to overcome.
As the researchers note, most research into finding a drug that can cause weight reduction in people with obesity issues has centered around appetite reduction. As the researchers note, thus far, this approach has not proved feasible, those that work to some degree cause serious side effects. Thus, the researchers with this new effort chose to direct their efforts directly at fat cells.
The research involved two basic steps, the first was to develop a carrier that would not only carry a gene therapy to fat cells, but would bind to them, allowing the therapy the opportunity to do its work. They developed one by putting together a short peptide with a gene sequence that targets fat cells. The result was a nine-amino-acid adipocyte targeting sequence that not only was able to bind to fat cells, but allowed for entering the cell nuclei, the carrier binds with fat cells by sticking to a protein found on their surface. Next, the researchers loaded the carriers with short hairpin RNA which prior research has shown is able to silence the fatty acid protein-4, injecting the carrier and its cargo into fat test mice that continued to be fed a high-fat diet showed weight loss in excess of 20 percent along with a higher tolerance for glucose, improved insulin sensitivity and an overall increase in their metabolic profile—all positive outcomes.
Unfortunately, while the initial results were promising, the researchers found that the carriers also bound to fat cells in places that were not desirable, such as in the liver or kidneys, which would likely lead to health problems. Thus, much more research will need to be done before the team looks into whether the same type of delivery system might be feasible for human beings.