[Destruction of Aging Cells] Senolytics: A New Anti-Aging Solution
When cells age and cannot function normally, they either undergo autophagy (self-destruction) or signal immune cells to remove them.
However, as we age, immune cells also age, accumulating dysfunctional cells that cannot be eliminated. These cells, which cannot be eliminated, cause inflammation in surrounding healthy cells, contributing to aging and disease, hence the name "zombie cells."
Senolytic = Senescence (aging) + lytic (destruction)
Senolytic drugs: from discovery to translation J.L. Kirkland & T. Tchkonia
Compounds called "senolytics" eliminate senescent cells that accumulate in the body. Preclinical studies have demonstrated that senolytics can slow aging, and quercitin and theaflavins, found in black tea, have senolytic effects and have recently become widely used.
Aging of "senescent cells"
When we're young, cells naturally remove themselves when they're damaged or no longer functioning properly. This process is called autophagy.
However, as we age, dysfunctional senescent cells fail to perform their normal functions and produce various toxins, which damage young cells and accelerate aging. From a biological perspective, senescent cells undergo a series of mutations that result in high levels of secretion, which secrete inflammatory factors called 'SASP' (Senescence-Associated Secretory Phenotype), which not only damage surrounding normal cells but also suppress immunity and can cause cancer.
Interestingly, because senescent cells are protected from damage by SASP inflammatory factors through a mechanism called 'SCAP' (Senescent Cell Anti-Apoptotic Pathways), senescent cells are not eliminated like zombies, but continue to function and cause inflammation in surrounding normal cells. As a result, aging is accelerated and the risk of various diseases caused by aging (diabetes, obesity, vision loss, degenerative diseases, dementia, arthritis, etc.) increases.
Research suggests that for every 7,000 to 15,000 normal cells, just one senescent cell is responsible for degenerative aging. Therefore, eliminating senescent cells could potentially improve overall health.
Fisetin, the most powerful natural senolytic substance
The flavonoid 'fisetin' is currently considered the 'most powerful senolytic substance' among polyphenol antioxidants.
Fisetin is a natural polyphenol found in fruits and vegetables such as strawberries, apples, persimmons, and onions, and research has shown that it eliminates about 70% of senescent cells.
Preclinical studies have shown that fisetin's various effects extend lifespan, extending lifespan by approximately 10% in aged mice administered fisetin. This is equivalent to extending the lifespan of a 75-year-old human by 7-8 years. Furthermore, fisetin not only enhances cognitive function by increasing cerebral permeability and thus helps prevent dementia, but also influences calorie-suppressing mechanisms, potentially helping with obesity and diabetes.
<Source of information>
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