No one knows why we age at the rate we do. Aging is a complex process that involves DNA damage, wearing down of body parts and the eventual decline of one's health because the body's rate of cell turnover slows down considerably.

Scientists from the Albert Einstein School of Medicine may have a new tidbit of evidence that may indicate how the brain may control aging of the whole body. Researchers blocked a protein called NF-κB (Nuclear Factor Kappa-light-chain-enhancer of activated B cells) selectively in the hypothalamus section of the brain. This region of the brain is known to link the nervous system to the endocrine system, so the body maintains proper hormonal balance.

Mice typically live for around 600-1,000 days. When researchers blocked the molecule's natural production, the found that the mouse's lifespan increased to 1,100 days. Alternatively, when scientists increased expression of the protein in the brain, all of the mice lived less than 900 days.

The mice that aged faster and died earlier, as a result of NF-κB expression, also had less muscle strength and size, their skin was thinner and they had a decreased ability to learn.

"It's clear from our study that many aspects of aging are controlled by the hypothalamus. What's exciting is that it's possible - at least in mice - to alter signaling within the hypothalamus to slow down the aging process and increase longevity." said Dr. Dongsheng Cai, M.D., Ph.D., professor of molecular pharmacology at Einstein.

The scientists found that a hormone released by the hypothalamus that is associated with reproduction called gonadotropin-releasing hormone (GnRH) was lower in mice that had a suppressed NF-κB expression and lived longer.

Researchers then injected the hormone into the hypothalamic ventricle (chamber) in the hypothalamus of elderly mice and saw that their cognitive skills did not decline rapidly, which may have been due to the growing of new neurons in the brain.

The researchers propose that GnRH may be a valuable tool to prevent cognitive decline in the aging population.

The research published in Nature can be found here.