Fisetin Reduces Covid Mortality in Old Mice

Fisetin is a substance that can extend lifespan in multiple species (R,R,R). Fisetin is mostly known for its ability to clear senescent cells, which accumulate during aging (R).

What’s less known is that fisetin can also reduce inflammation, and incite cells to better defend and repair themselves.

This can be of use in aging, in which the cells protect themselves better against damaging aging processes, but can also help cells to better cope with (and survive) immediate insults — like a serious infectious disease, such as covid-19.

Old mice, infected with SARS-CoV-2 that received fisetin, had significantly higher rates of survival compared to old mice without fisetin (R):

Old mice receiving fisetin (blue) survived much better an infection with covid compared to old mice receiving no fisetin (black).
Source: Senolytics reduce coronavirus-related mortality in old mice. Science, 2021

According to the researchers:

“Consistent with our previous results, 100% of the old mice in the vehicle control groups died within 2 weeks. However, 64% of the fisetin-treated male mice and 22% of the female mice survived long-term with a significant extension of overall lifespan for both sexes.”

The researchers could not explain why female mice survived less well compared to male mice (yet still survived much better than female mice that didn’t receive fisetin).

How fisetin can reign in too much inflammation

White blood cells are involved in inflammation.

The scientists speculate that when the mice are old, many senescent cells linger in their bodies. These senescent cells secrete proinflammatory substances, contributing to aging. Viruses like covid can make senescent cells even more proinflammatory, which can lead to too much inflammation, killing the mice.

Fisetin is known to clear senescent cells, and by that not only extending lifespan, but also reducing inflammation, which can be highly useful in very inflammatory conditions, like a covid infection.

Fisetin as a COVID treatment?

We are not recommending to use fisetin to treat covid-19. It is however interesting to know that natural substances like fisetin can help cells to protect themselves against both immediate damage (like serious infections) and long-term damage (e.g. aging) (R).

Nonetheless, there are ways to reduce the risk of covid-19, and to increase survival when infected.

Various studies show that vitamin D, zinc, vitamin C and magnesium can reduce the risk of getting Covid and/or can lead to better outcomes for people who are suffering from covid (R).

A small study showed that critically ill patients that receive NMN, together with zinc, sodium chloride and betaine, have higher rates of survival (R).

Weight loss, reducing metabolic problems like insulin resistance, and adhering to a healthy diet and lifestyle in general all can significantly reduce the risk of becoming very sick or dying of covid-19. And of many other infectious and non-infectious diseases!