Βrecent research at the Institute of Molecular Biology and Biotechnology (IMBB) of the Foundation for Research and Technology – Hellas (FORTH) and the Universities of Paris Cité in France and Graz in Austria, whose results are published today in the prestigious international scientific journal Nature Cell Biology, unveils the mechanism by which spermidine regulates autophagy, the process that ensures the recycling of components within the cell, promoting the anti-aging effects of intermittent fasting.
The researchers from IMBB-FORTH, including Dr. Ioanna Daskalaki and Dr. Ilias Gikas, led by Dr. Nektarios Tavernarakis, professor at the University of Crete’s Medical School and president of FORTH, collaborated with the research teams of Dr. Guido Kroemer, a professor at Paris Cité University in France, and Dr. Frank Madeo, a professor at Graz University in Austria, demonstrating that intermittent fasting increases levels of spermidine (a polyamine), which enhances the resilience and survival of cells and organisms by activating autophagy.
Autophagy, as noted by the researchers, is a cellular recycling process involving the degradation of non-functional or unnecessary cellular components and organelles. Disruptions in autophagy have been linked to aging and the onset of associated diseases, such as diabetes, cardiovascular diseases, cancer, and neurodegenerative disorders. Dietary habits, including low-fat or high-fat diets, overeating, or fasting, can influence these chronic diseases, the prevalence of which is expected to rise in the upcoming years.
Furthermore, it is noted that dietary interventions, such as caloric restriction and intermittent fasting, can slow aging and extend lifespan, provided that cellular homeostasis is maintained through the induction of autophagy. Under these circumstances, it is clarified that the administration of spermidine offers an alternative strategy for inducing autophagy and increasing lifespan. However, the role of spermidine in regulating autophagy and aging during intermittent fasting remains unclear.
Utilizing a range of experimental organisms, such as the nematode (Caenorhabditis elegans), yeast (Saccharomyces cerevisiae), fruit fly (Drosophila melanogaster), mouse (Mus musculus), and human cell lines, the research teams led by Professors Nektarios Tavernarakis, Guido Kroemer, and Frank Madeo demonstrated that intermittent fasting boosts cellular levels of spermidine, which in turn enhances autophagy, resulting in increased lifespan of these organisms. Conversely, the inhibition of spermidine synthesis using specific inhibitors nullifies the benefits of autophagy in prolonging lifespan through intermittent fasting.
The research findings, published today, highlight the critical role of spermidine in regulating autophagy under conditions of intermittent fasting, thereby improving lifespan in all studied organisms.
The fact that the regulation of autophagy through spermidine and intermittent fasting is an evolutionarily conserved process underscores its central role in monitoring and maintaining cellular homeostasis across various organisms. The study by the researchers at IMBB and their collaborators sheds light on how dietary habits can influence aging in humans and suggests new strategies for addressing age-related diseases, aiming to enhance both lifespan and quality of life.
