They did not gain any more weight than those control animals that consumed normal diets.
About a third of American adults is obese, the study in the journal eLife explains, and it is about more than just physical appearance - obesity has been linked to serious health problems like cardiovascular disease and diabetes. They engineered mice with genes that activated the Hedgehog pathway in fat cells.
Long added that, "It will take some work to make the mouse method work for humans, who also have Hedgehog pathways, but this could lead us to a new therapeutic target for treating obesity". The activation of a protein pathway in fat cells in the mice allowed the animals to be fed a high-fat diet without becoming obese.
The team claims that the Hedgehog pathway keeps blocks the development of the fats beyond a certain size.
"...animals with the active Hedgehog pathway not only were leaner, they also had lower blood-glucose levels and were more sensitive to insulin."This can lead to weight gain and obesity - which is a risk factor for, and some types of. The research result showed that though the mice on such a diet did not become extremely obese, the lab mice that did not have the special genes became fat. By stimulating Hedgehog and related proteins in fat cells, Long's team kept the animals' fat cells from collecting and storing fat droplets.
"Fat gain is due mainly to increased fat cell size", said senior investigator Fanxin Long, a professor of orthopedic surgery at Washington University in St. Louis. However, it could result in a new therapy to treat obesity. "If we can come up with strategies to carefully target fat cells, then I think activating this pathway could be effective in the fight against obesity", he said. "Each fat cell grows bigger so that it can hold larger fat droplets".
To explore if Hedgehog signaling also has an effect on diet-induced obesity after birth, Long and his team genetically engineered mice so that the Hedgehog pathway in fat cells would activate when they ate a high-fat diet.
When the fat cells begin to expand, that is when the person tends to gain weight- as opposed to having more fat cells.