Redox-regulating sirtuins in aging, caloric restriction, and exercise

Area of Science:

• Cellular Metabolism and Aging
• Enzymology and Molecular Biology

Background:

• Decreased nicotinamide adenine dinucleotide (NAD(+)) levels due to oxidative stress alter sirtuin activity, impacting mammalian cellular metabolism.
• Sirtuins, particularly SIRT1, regulate transcription factors involved in cellular redox state and DNA repair.
• The role of SIRT1 in DNA repair is complex, with both activating and inhibitory effects on different enzymes.

Purpose of the Study:

• To critically evaluate the age-associated roles of sirtuins in cellular processes.
• To review the involvement of sirtuins in longevity and disease prevention mediated by caloric restriction (CR) and physical exercise.
• To explore sirtuin-regulated pathways involved in health promotion.

Main Methods:

• Literature review and critical evaluation of existing findings on sirtuins.
• Analysis of sirtuin involvement in cellular metabolism, DNA repair, and aging.
• Examination of the impact of caloric restriction and physical exercise on sirtuin pathways.

Main Results:

• Sirtuins are involved in numerous cellular processes mediating longevity and disease prevention in mammals, influenced by CR.
• Physical exercise activates sirtuin-regulated pathways crucial for antioxidant defense, DNA repair, energy homeostasis, mitochondrial function, and neuronal plasticity.
• The precise role of SIRT1 in DNA repair remains multifaceted, affecting enzymes involved in damage response.

Conclusions:

• Sirtuins are central to cellular housekeeping, redox regulation, and mediating the health benefits of CR and exercise.
• Understanding the age-associated roles of sirtuins is crucial for developing strategies for longevity and disease prevention.
• Sirtuin activity is a key link between lifestyle factors (diet, exercise) and healthy aging.