It’s been said that there is just one thing in life that humans can’t control: our age.
Like it or not, at the end of every day we’re 24 hours older and one step further along the path to death.
But that’s just philosophy. On the biological side there are some very good reasons that our bodies change as we get older. Aging is hodgepodge of metabolic processes, damages, and pathologies with multiple points of intervention – it’s not one disease.
As we age, our cells enter a state called senescence. These harmful cells do not support the cells of which they are a part, and as we grow older, their accumulation is one of the key factors of aging.
Aging is the leading risk factor for the chronic diseases that account for the bulk of morbidity, mortality, and health costs. Geroscience is the study of longevity and aging and aims to identify the damages that accumulate with age, identify how to reverse these damages, and identify ways to increase the human lifespan. The goal is to prevent and delay age-related diseases.
The Silver Tsunami is coming
But there’s a problem brewing.
The demographics of aging is one of the greatest problems threatening economics and social stability today. An individual’s final years are the costliest to the healthcare system, with more doctor visits, more pharmaceutical needs, more hospital visits, etc. And we’re about to have a lot more older people on the planet that need these services.
According to the U.S. Census Bureau, as of 2010 just over 25% of the world’s population was aged 45 and older. That’s going to change in a big way by 2040 though, jumping to more than 30% in the older cohort.
Very soon, a lot more people are going to need medical care as they age. And demand is increasing. That’s why the U.S. National Institutes of Aging (NIH) has made the “compression of morbidity” one of its key long-term health targets and flagged it as the only sustainable solution to extend healthy lifespans.
A new class of drugs known as senolytics is focused on “solving for age” by addressing the natural cell destruction that happens in the body as we get older. By both preventing this cell destruction and reversing its effects, these seneotherapeutics can both improve tissue function and increase human healthspans (that is, healthy lifespans).
These therapies, while still in their early days, offer great promise.
Senolytics work by eliminating senescent (or dying) cells and attenuating the Senescence Associated Secretory Phenotype, SASP. This makes it an attractive therapeutic strategy for aging and associated diseases. The different types of seneotherapeutics include geroprotectors, which prevent or reverse the senescent state by preventing triggers of cellular senescence, such as DNA damage or oxidative stress; SASP inhibitors, which interfere with pro-inflammatory senescence-associated secretory phenotype (SASP); senolytics, which are drugs that selectively kill senescent cells; and senomorphics, which are drugs that suppress senescence.
The key advantages of senolytics as a treatment include the permanent removal of the SASP source that’s causing cell damage, the fact that it allows for intermittent treatment, and the fact that it also eliminates senescent cells that may be preneoplastic (i.e. pre-cancerous).