On the mechanisms of ageing suppression by dietary restriction-is persistent glycolysis the problem?

Area of Science:

• Biochemistry
• Gerontology
• Metabolic pathways

Background:

• Dietary restriction (DR) is known to suppress aging and age-related diseases.
• Glycolysis, a key metabolic pathway, involves intermediates that can be toxic.
• Methylglyoxal (MG), a reactive byproduct of glycolysis, can damage proteins and mitochondria.

Purpose of the Study:

• To explore the mechanisms by which DR suppresses aging.
• To investigate the role of glycolysis frequency and intermediate reactivity in aging.
• To assess the impact of methylglyoxal (MG) on cellular senescence and mitochondrial function.

Main Methods:

• Review of existing literature on dietary restriction, glycolysis, and aging.
• Analysis of the reactivity of glycolytic intermediates, particularly methylglyoxal (MG).
• Discussion of cellular protective mechanisms against MG, including glyoxalase, carnosine synthetase, and ornithine decarboxylase.

Main Results:

• DR is associated with reduced glycolysis compared to ad libitum feeding.
• Lowered glycolysis during DR leads to decreased intracellular MG levels.
• Reduced MG levels may protect against protein glycation, mitochondrial damage, and oxidative stress, thereby delaying senescence.

Conclusions:

• Reduced glycolysis and lower methylglyoxal (MG) levels are proposed mechanisms for DR-mediated lifespan extension.
• Persistent high MG levels from continuous glycolysis may accelerate aging and senescence, especially in non-mitotic tissues.
• Dietary interventions impacting intracellular glycating agents could influence age-related mitochondrial dysfunction.