According to some new research, the key to living longer may reside deep in our brains. In a major breakthrough for our understanding of how the brain controls aging, scientists managed to both speed up and slow down the aging process in mice by disrupting the volume of neural stem cells found in the hypothalamus.
Back in 2013, a team from New York's Albert Einstein College of Medicine discovered that a region of the brain called the hypothalamus seemed to play a key role in the way the body regulated its aging processes. The hypothalamus was already known for being responsible for many functions, including growth, development, reproduction and certain metabolic processes, but its relationship with aging was new.
Now those scientists have discovered that a tiny population of stem cells situated inside the hypothalamus could hold the key to how the body regulates aging.
"Our research shows that the number of hypothalamic neural stem cells naturally declines over the life of the animal, and this decline accelerates aging," says Dongcheng Cai, senior author in the research.
The initial studies involving mice looked at the correlation between age and the number of hypothalamic stem cells. It was observed that as healthy mice got older, the number of these stem cells began to diminish. "By old age – about two years of age in mice – most of those cells were gone," says Dr. Cai.
In order to confirm the connection between aging and these stem cells, the scientists then selectively disrupted the hypothalamic stem cells in middle-aged mice. This action was observed to significantly accelerate the aging process of mice compared to a control group.
The final, and most exciting, stage of the team's research was to experiment with whether an addition of hypothalamic stem cells to the brain could actually counteract aging. Hypothalamic stem cells were injected into the brains of healthy old mice and the treatment was seen to slow, or even in some instances reverse, various measures of aging.
In trying to understand how this anti-aging action was occurring, the researchers discovered that these hypothalamic stem cells released molecules called microRNAs (miRNAs) into cerebrospinal fluid. When the researchers replicated this process artificially by injecting extracted miRNAs into the cerebrospinal fluid of mice, they again observed significantly reduced measures of aging.
This breakthrough discovery doesn't offer us an immediate "fountain of youth" treatment for living forever, but it does deliver researchers a new understanding into how the hypothalamus seems to act as a central command center for controlling aging. Alongside the myriad of other anti-aging research currently occurring, from epigenetic regulation to a new class of drugs called senolytics, it is becoming increasingly believable that future generations of humans could live significantly longer than we do now.
The research was published in the journal Nature.