Eating a high-fat diet may rapidly injure brain cells that control body weight

Obesity among people who eat a high-fat diet may involve injury to neurons, or nerve cells, in a key part of the brain that controls body weight, according to the authors of a new animal study. The results will be presented Tuesday at The Endocrine Society's 93rd Annual Meeting in Boston.

"The possibility that may be a consequence of the of a typical American diet offers a new explanation for why sustained weight loss is so difficult for most to achieve," said presenting author Joshua Thaler, MD, PhD, a faculty member with the Diabetes and Obesity Center of Excellence at the University of Washington in Seattle.

Thaler and his colleagues studied the brains of rodents for the short-term and long-term effects of eating a high-fat diet. After giving groups of six to 10 rats and mice a high-fat diet for periods from one day to eight months, the researchers performed detailed biochemical, imaging and cell sorting analyses on the animals' brains.

Within the first three days of consuming a diet that had a similar to the typical American diet, rats consumed nearly double their usual daily amount of calories, Thaler reported. Rats and mice fed the high-fat diet gained weight throughout the study. These rodents developed inflammation in the hypothalamus, the part of the brain containing neurons that control body weight. At the same time, a group of support cells called glia and scavenger cells called microglia accumulated in the and appeared to become activated. Although this collective response to —called gliosis—subsided days later, it recurred after four weeks.

"Gliosis is thought to be the brain equivalent of wound healing and is typically seen in conditions of neuronal injury, such as stroke and multiple sclerosis," Thaler said. "We speculate that the early gliosis that we saw may be a protective response that fails over time."

In their experiments, Thaler said they also detected damage to, and eventual loss of, critical weight-regulating neurons. These neurons, called pro-opiomelanocortin (POMC) neurons, were reduced in number by month 8 of the high-fat diet in mice, according to Thaler. These results were not present in same-age rodents fed standard chow.

It is not yet clear whether this presumed neuronal injury is permanent, but it may contribute to weight gain, he stated.

This research, which was funded by the National Institute of Diabetes and Digestive and Kidney Diseases, provides a new potential target for obesity treatment, Thaler concluded.

"If new medicines can be designed that limit neuron injury during overeating, they may be effective in combating the obesity epidemic," he said.

add to favorites email to friend print save as pdf

Related Stories

Research Shows Some May Be Wired for Wider Waists

Aug 05, 2010

(PhysOrg.com) -- Development of obesity may be predetermined by how neurons in the brain are plugged together. New research from the University of Cincinnati (UC) shows that the amount of weight gained from ...

Recommended for you

The impact of bacteria in our guts

Aug 22, 2014

The word metabolism gets tossed around a lot, but it means much more than whether you can go back to the buffet for seconds without worrying about your waistline. In fact, metabolism is the set of biochemical ...

Stem cell therapies hold promise, but obstacles remain

Aug 22, 2014

(Medical Xpress)—In an article appearing online today in the journal Science, a group of researchers, including University of Rochester neurologist Steve Goldman, M.D., Ph.D., review the potential and ch ...

New hope in fight against muscular dystrophy

Aug 22, 2014

Research at Stockholm's KTH Royal Institute of Technology offers hope to those who suffer from Duchenne muscular dystrophy, an incurable, debilitating disease that cuts young lives short.

Biologists reprogram skin cells to mimic rare disease

Aug 21, 2014

Johns Hopkins stem cell biologists have found a way to reprogram a patient's skin cells into cells that mimic and display many biological features of a rare genetic disorder called familial dysautonomia. ...

User comments