Does clearing out senescent cells with senolytics help against ageing?
Senolytics show impressive results in animal studies, but in people the evidence is too thin for use outside a research setting. Self-medicating with Dasatinib is inadvisable given its side effects and the risks around tumour growth.
Senescent cells stop dividing but do not die. They build up as you get older and continuously release harmful substances into their surroundings. In animal studies, removing those cells with senolytics has been strikingly successful: more than 40 conditions, from heart and kidney problems to bone disease and brain disorders, appeared to improve or slow down. But what works in mice does not always work in people.
In people, the evidence is still very thin. The most-cited study in people tested a combination of Dasatinib (a powerful drug normally used in cancer treatment, 100 mg) and Quercetin (a supplement, 1000 mg) in just 9 people with diabetic kidney disease, over 3 days. Within 11 days, the number of senescent cells in fat tissue and skin dropped measurably, and harmful substances in the blood also decreased. However, there was no control group, and several of the researchers involved benefit financially through patents held at the Mayo Clinic.
Studies in people are under way into senolytics (agents that clear out senescent cells) for diabetes, pulmonary fibrosis, Alzheimer's disease, osteoarthritis and bone loss. Whether they also make a difference for the brain is an open question, with many uncertainties still remaining. Large-scale evidence on safety and effectiveness is lacking for now.
An important safety point: senescent cells are not simply harmful. Shortly after they form, they actually suppress tumour growth. Only when they persist for a long time can they promote tumour growth through the harmful substances they release. Using senolytics at the wrong moment may therefore carry risks. Dasatinib is also a powerful drug with well-known side effects.
Some attention is also being paid to a senolytic cream for the skin, but that idea is speculative and has not been demonstrated in people. Quercetin is freely available as a supplement, but the available data in people are far too limited to support a safe or effective dose for healthy individuals. Experts agree: senolytics still belong in a research setting, not in your own medicine cabinet.
Seven claims are based on six PMID sources. The only direct study in people involves 9 participants with no control group. The remaining sources are primarily review articles covering animal data and mechanistic research. No large controlled studies in people are available in this source set.
What exactly does senescence do to your cells as you age?
Senescent cells stop dividing and secrete inflammatory substances that damage tissues over time. They are necessary in youth, but when they accumulate they accelerate ageing and disease.
Can meditation do anything about ageing at the cellular level?
Meditation appears to activate an enzyme that protects chromosome caps from ageing, although the studies are still too small to draw firm conclusions. Meditation is in any case safe and has positive effects beyond cell biology, so the barrier to trying it is low.
Does chronic inflammation accelerate the ageing of your cells?
Chronic inflammation demonstrably accelerates cellular ageing through a negative spiral that is difficult to break. The best evidence-based approach to tackling that spiral is through lifestyle factors that dampen low-grade inflammation, such as sufficient exercise and a diet low in ultra-processed products.
Do sirtuins actually do anything against ageing?
Sirtuins play a clear role in ageing in animal research, but whether they are of any benefit to humans (through supplements or other means) remains unknown. Wait for human evidence before acting on any sirtuin-based claims.
Do senolytics already work in humans, or only in mice so far?
Senolytics no longer work only in mice: there is now first concrete evidence in humans, but the studies are small and lack long-term outcomes, so they cannot yet be relied upon as a proven treatment.
What do zombie cells do to your ageing?
Zombie cells accumulate as you age and accelerate ageing through inflammatory signals; how to tackle them is promising but still very much under investigation.