There’s a huge market for diet products, cosmetics, and supplements claiming to help you look and feel younger. These products make billions of dollars worldwide, but most don’t have significant, proven health benefits.
At best, they may keep the more obvious and undesirable effects of aging at bay for a short time. But researchers at the Albert Einstein College of Medicine are researching a different way to look and feel younger – to actually be younger, biologically speaking.
The new study, published last month, focuses on a section of the brain called the hypothalamus, a small region of the brain with a big job. The hypothalamus coordinates your nervous system and your endocrine system. It regulates body temperature, hunger, thirst, some instinctive behaviors, fatigue, sleep, and sleep-wake cycles. Scientists have long suspected that the hypothalamus may play a special role in regulating how and when mammals begin to age, but this study offers the first hard evidence that stem cells in the hypothalamus play a pivotal role in aging.
Stem cells are famous for their unique ability to develop into many different types of cells, and since the beginning of stem cell research in the mid-20th century, the possibilities of these cells have fascinated scientists and researchers, some of whom believe they hold the key to curing diseases, replacing failing organs, and defying aging. A few years ago, the authors of last month’s study were enthused to discover stem cells in the hypothalamus, and those findings led to their current research.
Researchers working with mice found that the number of hypothalamic stem cells in young adult brains begins decreasing before any noticeable signs of aging, and by the time old age sets in there are hardly any neural stem cells left in the hypothalamus at all. To determine whether or not there was a direct relationship between aging and stem cells, the researchers disrupted the neural stem cells in some mice and found that mice with disrupted stem cells aged faster and died earlier than usual.
To figure out whether or not the aging process could be slowed, the researchers “transplanted” a fresh supply of neural stem cells into middle-aged mice. To the researchers delight, the mice that received neural stem cell supplementation showed significantly slowed signs of aging.
The mice in the group that received stem cells showed evidence of younger muscles and minds. They even showed more interest in socializing with their peers and lived about 10% longer than expected. Despite these incredible findings, scientists are quick to emphasize that there’s no single key to aging. The process is far too complicated for that. Hypothalamic stem cells seem to play a key role, but other factors, such as changes to the way the body regulates inflammation, have parts to play as well. For example, in order to protect the “transplanted” stem cells in older mice, the researchers had to tinker with their genes to reduce inflammatory responses that could have made the cells less effective. These inflammatory responses increase with age and can destroy stem cells.
So if you’re thinking you might be going to a clinic for age-defying stem cell transfusions in a few years, that’s probably overly optimistic. Researchers from all over the world are interested in the new findings, but we’re a long way off from finding a safe way to produce the same effect in humans. Injecting cells into the brain isn’t exactly standard medical care.
In their research, the scientists were able to isolate the mechanism behind stem cells’ anti-aging effects, narrowing it down to the action of microRNAs, compounds released by hypothalamic neural stem cells in small fatty capsules. The next step for scientists is to figure out exactly which of the many types of microRNAs are responsible for the anti-aging effects observed in the study, and that research alone could take years.
And even if further research backs up these new findings, you can expect therapies based on the findings of this study to take decades to develop. Researchers are a long way off from safe, human trials, and those trials themselves will take years to play out since they’ll involve observing the effects of aging over a period of time. But regardless of its practical applications for today, the idea of slowing, or even halting, aging captures the imagination in a way few medical breakthroughs can.