Protein that regulates fat metabolism in the liver is also responsible for the proper functioning of memory, informs Cell Reports.
Although there are many causes of dementia, being overweight is one of the risk factors. In middle-aged people, belly fat increases the risk of dementia by 3,6 times later in life.
Researchers from Rush University Medical Center (USA) in collaboration with the US National Institutes of Health localized high levels of the peroxisome proliferator-activated alpha receptor (PPARalpha) in the mouse hippocampus (the brain structure responsible for memory and learning). So far, it has been known that high expression of this protein takes place in the liver.
PPARalpha directly controls fat metabolism. People with a lot of belly fat have reduced levels of this protein in the liver. With a disturbed metabolism, the level of PPARalpha in the liver drops first, and then in the entire body, including the brain. Abdominal fat may therefore be an early predictor of dementia later in life, explains study author Dr Kalipada Pahan.
In mice with normal levels of PPARalpha in the liver, but decreased levels of PPARalpha in the hippocampus, memory was worse than in rodents with normal levels of PPARalpha in the brain and low in the liver. For the first group of mice, memory improved after injection of PPARalpha into the hippocampus.
As the researchers note, PPARalpha stimulates the CREB (cyclic AMP response element-binding protein) protein, which controls various other proteins that affect memory.
Further research will help determine whether it will be possible to maintain normal levels of PPARalpha in the brain to prevent the development of dementia, says Dr. Pahan. (PAP)