We commonly hear about inflammation when someone talks about arthritis or other joint pain. But fat tissue can also become inflamed, and the inflammation of fat tissue can cause a wide range of health problems for overweight and obese people. Scientists have been trying to determine what exactly causes that inflammation, and new research from the Methodist Hospital in Houston suggests that the cause may be the fat cells themselves. According to a study published in Cell Metabolism, fat cells themselves are at least partly to blame for the process. High calorie diets cause the cells to make major histocompatibility complex II (MHCII), which is a group of proteins usually expressed when the immune system needs to fight off bacteria or viruses. These fat cells in overweight mice and humans can send out false distress signals. The system thinks it is in danger – even though it is not actually under attack – and it initiates inflammation to try and protect itself. It was previously believed that fat cells didn’t do much other than storing and releasing energy. The expression of MHCII in fat cells does not seem to help the body, but appears to be a runaway immune response to a modern high calorie diet. Inflammation of fat tissue has many negative long-term consequences, including insulin resistance and, in time, diabetes.
One of the most interesting implications of this finding, in terms of obesity research, is that it may lead to the identification of a new drug target for the treatment of obesity. The researchers explained that while “blocking the MHCII response of fat cells wouldn’t cure obesity, it could make it possible for physicians to alleviate some of obesity’s worst consequences while the condition itself is treated.” The next step is to identify which MHCII antigen (a substance that causes the immune system to produce antibodies) is involved in the inflammatory response of fat tissue to weight gain.
Related Reading: Losing Weight Lowers Systematic Inflammation
Weight Loss Studies & Clinical