TOKYO (Dispatches) -- According to a new study, scientists have discovered a protein that plays a key role in how the brain regulates appetite and metabolism. Loss of the protein, XRN1, from the forebrain, resulted in obese mice with an insatiable appetite.
During the research, the scientists from the Okinawa Institute of Science and Technology created mice that were unable to produce the protein, XRN1, in a subset of neurons in the forebrain. This brain region includes the hypothalamus, an almond-sized structure that releases hormones into the body, helping to regulate body temperature, sleep, thirst and hunger.
At 6-weeks-old, the scientists noticed that the mice without XRN1 in the brain rapidly began to gain weight and became obese by 12 weeks of age. Fat accumulated in the mice’s body, including within adipose tissue and the liver.
They also also found that 5-week-old mice were resistant to insulin, a hormone that is released by beta cells in the pancreas in response to the high levels of blood glucose that occur after eating. This type of failure in how the body responds to glucose and insulin can ultimately lead to diabetes. As the mice got older, levels of glucose and insulin in the blood rose significantly alongside the increased leptin levels.