Not all fat is bad for you. The most common type of fat in our bodies, known as “white” fat, is a tissue that stores energy in the form of lipids, and makes us gain weight when we introduce too much of it through our diet. But there is another type of fat, called “brown” fat, which is made up of cells that instead burn lipids to heat the body, and therefore, basically, helps you lose weight. And a new study by researchers at the University of California, San Francisco suggests that it may be possible to develop a drug that can push white adipose tissue to behave like brown fat, resulting in an obesity therapy that would allow you to lose weight with virtually no effort.
In this case, the focus of the research is on so-called beige adipocytes (fat cells), cells found in white adipose tissue that behave like brown cells, burning fat to produce heat. The transformation of white fat into beige fat occurs naturally in the body of adults, but it is quite rare and linked to mechanisms that are still unclear. For this reason, many research groups, such as the one at the University of California, are looking for a way to promote it with a drug, in order to obtain an anti-obesity therapy.
Their previous research had already highlighted the role that a protein known as Klf15, produced by the body following fasting or exercise, plays in fat metabolism. By analyzing the levels of this protein contained within different types of adipocytes, the researchers noticed that it is significantly more abundant in white ones. A discovery that led them to wonder what could happen to the cells in question by eliminating Klf15.
Their research showed that exposing white adipose tissue to a substance known to induce the activation of beige adipocytes reduces the production of KLF15. And that the phenomenon is mediated by a molecular mechanism involving a cellular receptor known as Adrb1. At this point, the researchers created genetically modified mice to be able to modulate the production of KLF15 within their organism. And they discovered that reducing the production of this protein increases the activation of Adrb1, and that under these conditions the white fat of the animals begins to exhibit behavior similar to that of beige fat.
By developing a drug that mimics the activity of Adrb1, it may be possible to push white adipocytes to behave like brown cells, and therefore burn fat more easily. These are studies that have yet to begin, but having already demonstrated that this is a promising path is an important result. “Many people thought it was impossible,” explains Brian Feldman, of the Brian Feldman Nutrition and Obesity Research Center at the University of California, San Francisco and co-author of the study. “And instead we have shown not only that this approach works, but also that the bar for making it work is much lower than we thought.”