Scientists have discovered yet another potential cause for obesity, particularly middle-aged obesity.
Researchers have discovered that obesity in middle-aged people may be caused by the shape of neurons in one’s brain.
Scientists from Nagoya University, the University of Tokyo, and the Nagoya University Research Institute of Environmental Medicine recently conducted a study on melanocortin-4 receptors (MC4R) in primary cilia extending from hypothalamic neurons in rats. This protein is known to regulate metabolism, nutrition, and appetite.
The scientists conducted these studies over 9-week-old (young) and 6-month-old (middle-aged) rats.
These scientists discovered that as the primary cilia shortened with age, MC4Rs also decreased, resulting in weight gain. The researchers also noted that middle-aged rats’ metabolism and fat-burning ability were lower than those of younger rats.
“We believe that a similar mechanism exists in humans as well,” said Professor Kazuhiro Nakamura, the study’s lead author, in a press release. We hope our finding will lead to a fundamental treatment for obesity.”
The researchers also analyzed these neuron structures with different dietary restrictions, noting that those on a tight diet saw the cilia shorten at a slower rate. In contrast, those on a high-fat diet saw the shortening occur at an accelerated rate. They also administered a hormone called leptin in an effort to reduce appetites; however, this was unsuccessful, with scientists concluding that this hormone cannot combat obesity.
Dr. Manami Oya, the study’s first author, said that this lack of effect, known as leptin resistance, has been noted in human patients and that the cause is still unknown.
“In obese patients, adipose tissue secretes excessive leptin, which triggers the chronic action of melanocortin,” said Oya in the release. “Our study suggests that this may promote the age-related shortening of MC4R+ cilia and put animals into a downward spiral where melanocortin becomes ineffective, increasing the risk of obesity.”
The researchers believe that a solution to prevent cilia from shortening over time is restricted diets.
“Moderate eating habits could maintain MC4R+ cilia long enough to keep the brain’s anti-obesity system in good shape even as we age,” added Nakamura.
Obesity continues to be an epidemic across the nation, with about 42.4% of adults suffering from the condition, according to the National Institutes of Health.
The U.S. Food and Drug Administration recently announced that Wegovy, a weight loss drug approved to treat obesity in children and adults, can also be used to mitigate heart attack, stroke, and cardiovascular disease risk in obese subjects, as previously reported by The Dallas Express.
