Senescence is an ethereal-sounding word. It’s not something you often hear in everyday conversation, and if you’re not a scientist who researches aging, you might not know it at all. It’s a term for biological aging, either in a body as a whole or at an individual, cellular level. Understanding senescence is vital if you want to reduce the side effects of aging.
Human bodies are made up of trillions of cells. They’re the basic structural unit of most living beings. Different cells can play different roles, which often involves them dividing, or turning into two or more. At some point, however, this division will stop, either because of natural deterioration or some kind of external stressor. This is senescence.
There are advantages to senescence. It may slow or stop cancer growth if you have a tumor, and it also helps with wound healing. You don’t want aged cells that are damaged or no longer working properly dividing or spreading. The trouble is that senescence seems to be associated with many of the negative signs of aging as well.
Senescent cells are associated with increased inflammation, which is a risk factor for all kinds of age-related conditions. DNA can deteriorate or become mutated or damaged. The role of senescence in managing tumors or tissue damage can become reversed. Common traits associated with aging and senescence include everything from a loss of fertility to an increased likelihood of death.
The immune system can remove senescent cells if they’re causing problems. Unfortunately, the immune system is something else that becomes less effective as we age. Senescent cells can begin to accumulate, meaning their effects become more pronounced. Research is being done to see if we can create senolytics. These are drugs that can destroy senescent cells, potentially reducing age-related disease and improving overall health.
A look at the list of conditions associated with senescence is a sobering one (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5748990/). Cardiovascular disease and liver disease are some of the most serious, along with the complicated relationship with cancer. Senescence may also be related to osteoarthritis, fibroids, weight gain and loss of muscle mass. It’s no wonder researchers are interested in investigating senescence further.
This is an area of science that’s constantly being studied, with our knowledge growing all the time. It may be one of the most important ways to delay aging or alleviate some of its worst effects.
