Spermidine has it all. Over the last ten years, researchers in Graz have been able to prove that the natural substance protects the heart and can stop age-related memory loss, among other things. The current study now shows that the spermidine concentration increases significantly in fasting humans, mice, flies and yeast cells. This stimulates autophagy, a cellular cleaning programme. Cellular waste produced during the ageing process is broken down. "With spermidine, we have found an important building block for the health-promoting effects of fasting," says Frank Madeo, emphasising the significance of the latest publication.

The study authors were able to observe an increase in fitness as well as an extension of health and lifespan in all of the organisms studied as a result of the fasting processes, as long as they were accompanied by an increase in spermidine concentration. "After we prevented the spermidine increase in various model organisms through chemical and genetic interventions, they were no longer able to trigger autophagy and the vitality-enhancing effect of fasting failed to materialise," reports Madeo.

Chronic inflammation is a significant accelerator of the ageing process. "In model organisms that suffered from arthritis, the inflammation improved with regular fasting. However, only if they were also able to produce spermidine," explains Sebastian Hofer, now a researcher at the Max Delbrück Centre in Berlin, using an example. The same applies to the heart-protective effects of fasting processes. "Additional doses of spermidine could possibly make various fasting regimes even more effective," Hofer surmises.

The research is part of BioHealth, a field of excellence at the University of Graz.

Publication
Spermidine is essential for fasting-mediated autophagy and longevity
Frank Madeo, Sebastian Hofer et al.
Nature Cell Biology, 8 August 2024
DOI: 10.1038/s41556-024-01468-x