Reversing Age-Related Weight Gain
Researchers at Cornell University have made a significant breakthrough in the fight against age-related weight gain by reactivating a unique type of fat known as beige fat. Unlike ordinary white fat, which primarily stores calories, beige fat actively burns energy similar to brown fat, contributing to improved blood sugar regulation and offering protection against heart disease.
This research offers a potential strategy to address the weight gain commonly associated with aging, which in turn may decrease the likelihood of developing obesity-related conditions such as Type 2 diabetes, cardiovascular disease, and chronic inflammation. Scientists are focusing on stimulating the production of a specific kind of fat cell that may help restore metabolic functions that decline with age. This exciting work originates from the Division of Nutritional Sciences within Cornell’s College of Human Ecology and College of Agriculture and Life Sciences.
Understanding Fat Types
In mammals, including humans, fat is primarily categorized into two types. White adipose tissue (WAT) serves as the body’s primary energy reserve, while brown adipose tissue (BAT) is responsible for burning calories to produce heat and maintain body temperature.
A recent study published in Nature Communications introduces a promising third type known as beige fat. This form of fat has characteristics of both white and brown fat, sharing cellular origins with white fat yet demonstrating the energy-burning abilities of brown fat. The implications of this dual functionality include lowering blood sugar levels and breaking down fatty acids that can lead to heart disease.
The Trigger for Beige Fat Production
Beige fat is typically activated when the body is subjected to prolonged cold exposure. Under these conditions, adipose progenitor cells transform into calorie-burning beige fat cells found within white fat reserves. Unfortunately, this ability diminishes with age, causing the body to produce more white fat.
“There are seasonal changes in beige fat in young humans,” said Dan Berry, assistant professor in the Division of Nutritional Sciences. “But an older person would have to stand outside in the snow in their underwear to get those same effects.”
Exploring Biochemistry Behind Aging Fat
In prior research, Berry identified that aging impairs the body’s capacity to generate beige fat cells in response to cold stimuli. He aims to uncover the underlying biochemistry behind this decline to reverse it with potential therapeutic benefits.
“This is the ultimate goal,” said Abigail Benvie, lead author and doctoral researcher in Berry’s lab. “Without having to subject people to cold exposure for prolonged periods of time, are there metabolic pathways we can stimulate that could produce the same effect?”
The recent study elaborates on a specific signaling pathway that inhibits beige fat formation in aging mice by negatively impacting the immune system. By suppressing this pathway, the researchers successfully stimulated beige fat production in older mice that would not have generated it otherwise.
The research paper titled “Age-dependent Pdgfrβ signaling drives adipocyte progenitor dysfunction to alter the beige adipogenic niche in male mice,” co-authored by Abigail M. Benvie and others, was published on March 1, 2023.
Expanding Research and Therapeutic Possibilities
Further studies have confirmed that Pdgfrβ signaling hampers the formation of beige fat as one ages, demonstrating that blocking this pathway can rejuvenate fat-burning activity in older mice. Notably, existing cancer treatments like fludarabine and imatinib have been observed to enhance beige fat production when coupled with cold exposure, presenting a promising therapeutic avenue. Additional investigations indicate that reversing this signaling interaction may also revive crucial immune cells that aid in beige fat maintenance, while other teams are exploring related molecular regulators.
These developments collectively strengthen the prospect that targeting beige fat could one day help mitigate age-related weight gain and metabolic diseases.
