With a typical lifespan of around six weeks, the common fruit fly is one animal that could benefit from a slowing of the aging process. And that's just what a team of biologists at UCLA have achieved by activating a gene called AMPK. Possibly of more interest to us higher life forms is the researchers' belief that the discovery could help delay aging and age-related diseases in humans.

AMPK (adenosine monophosphate-activated protein kinase) is an enzyme that acts as a metabolic master switch and is activated in response to low cellular energy levels. It has previously been shown to activate a cellular process known as autophagy, which protects against aging by enabling cells to degrade and discard old, damaged "cellular garbage" before it damages cells. Although AMPK is also found in humans, it is not usually activated at a high level.

The UCLA research team found that increasing the amount of AMPK in the intestines of common fruit flies (Drosophila melanogaster) increased their lifespan by around 30 percent, up from the typical six weeks to around eight weeks. Importantly, the fruit flies stayed healthier for longer as well, with the beneficial effects not restricted to the organ where it was activated.

"We have shown that when we activate the gene in the intestine or the nervous system, we see the aging process is slowed beyond the organ system in which the gene is activated," said David Walker, an associate professor of integrative biology and physiology at UCLA and senior author of the research.

"A really interesting finding was when Matt (lead author of the study, Matthew Ulgherait) activated AMPK in the nervous system, he saw evidence of increased levels of autophagy in not only the brain, but also in the intestine,” adds Walker. "And vice versa: Activating AMPK in the intestine produced increased levels of autophagy in the brain – and perhaps elsewhere, too."

Walker says that this approach could make it possible to slow the aging process throughout the entire body, including the brain, by accessing more accessible organs like the intestine, rather than key organs that are technically difficult to deliver treatments to.

"Instead of studying the diseases of aging – Parkinson’s disease, Alzheimer's disease, cancer, stroke, cardiovascular disease, diabetes – one by one, we believe it may be possible to intervene in the aging process and delay the onset of many of these diseases," said Walker. "We are not there yet, and it could, of course, take many years, but that is our goal and we think it is realistic. The ultimate aim of our research is to promote healthy aging in people."

The team's study appears in the open-source journal Cell Reports (PDF)


Source: UCLA