Small molecules that regulate lifespan: evidence for xenohormesis.

Area of Science:

• Aging and Longevity Research
• Molecular Biology
• Biochemistry

Background:

• Calorie restriction (CR) is the only known non-genetic method to slow aging in mammals, suggesting conserved mechanisms across species.
• The sirtuin family of deacetylases, originating in early eukaryotes, plays a role in stress response and longevity.
• Sir2, a sirtuin in yeast (Saccharomyces cerevisiae), is activated by CR and linked to extended lifespan.

Purpose of the Study:

• To investigate the conserved mechanisms underlying calorie restriction's anti-aging effects.
• To explore the role of sirtuins in mediating the benefits of calorie restriction.
• To examine the potential of plant-derived polyphenols in mimicking calorie restriction's effects.

Main Methods:

• Studied the effects of calorie restriction on lifespan in yeast (Saccharomyces cerevisiae).
• Investigated the activation of Sir2 and other sirtuins by calorie restriction.
• Examined the impact of plant-derived polyphenols on sirtuin activity and lifespan.

Main Results:

• Calorie restriction extends yeast lifespan by activating Sir2, a key longevity protein.
• Sirtuins, found across eukaryotes, are implicated in the health benefits of calorie restriction.
• Plant polyphenols activate sirtuins and mimic calorie restriction's lifespan-extending effects in yeast.

Conclusions:

• Sirtuins are conserved mediators of calorie restriction's anti-aging effects.
• The 'xenohormesis hypothesis' suggests organisms utilize external stress signals (like plant polyphenols) to prepare for environmental challenges.
• Plant-derived compounds offer a potential avenue for mimicking calorie restriction's benefits and promoting longevity.