The aging process is one that is simple to explain but maddeningly difficult to unravel. There are genetic, molecular, environmental, biological, and even possibly psychological influences that all go into the aging of the human body. At the University of New South Wales’ Laboratory for Aging Research, the focus is on the cellular level, and the findings have ranged from the interesting to the impressive.
Cellular Aging Through Senescence
One of the ways that the UNSW lab and its siblings have investigated the process of aging is through cellular senescence: the accumulation of age-related damage in a cell. Normally, senescent cells are cleared out by the body through destruction, or by reproducing into younger, fresher cells. These sorts of “housekeeping” behaviors decline as we age, and senescent cells end up accumulating in the body. They end up secreting inflammation-causing agents that irritate or damage nearby cells, resulting in a condition of chronic inflammation that is associated with numerous old-age diseases.
The idea, as demonstrated in a study from the Mayo Clinic, is that removing the excess senescent cells has the potential to extend lifespans, and also to improve general health overall. The latter may end up being more important than the former, since a longer life expectancy isn’t as meaningful if you’re just living longer in care.
Another area of exploration is a class of molecules called “sirtuins”, specifically the enzyme known as SIRT1. SIRT1 is what helps keep the structure of DNA tightly wound and optimized. The activity of the enzyme decreases as we age, and it is thought that invigorating SIRT1 could help mitigate or reverse the resulting dysfunctions.
The UNSW lab in particular made a discovery about SIRT1 back in 2003. It found that resveratrol, a compound found in red wine, made SIRT1 run faster. This helped develop research that showed SIRT1 could be targeted and paved the way for the creation of new treatments.
Diet and Exercise
Incidentally, two other sirtuins (SIRT3 and 4) are also tied to the link between longevity and low calorie intake. Calorie restriction and exercise are now known to activate these sirtuins, which may partially explain why diet and exercise are so useful for maintaining health through the years. Although it is important not to miss the forest for the trees, looking at the aging process at a cellular level has, and will continue to, show great promise for uncovering the secrets of age.
Williams, L., “Holding back the years,” UNSW Australia web site, September 19, 2016; http://newsroom.unsw.edu.au/news/health/holding-back-years, last accessed September 22, 2016.