Foundation of Ageing Science

What is Biological Ageing?

Biological ageing is broadly defined as the time-dependent functional decline that affects most living organisms. It is characterized by the progressive accumulation of damage at the molecular, cellular, and tissue levels. This accumulation eventually leads to a loss of physiological integrity, impaired function, and increased vulnerability to death.

Major Categories of Research

Modern geroscience—the study of the biology of ageing—typically categorizes ageing processes into several key "hallmarks" or pillars. While the exact list evolves, major areas of study include:

• Genomic Instability: The accumulation of genetic damage over time.
• Telomere Attrition: The shortening of the protective caps on chromosomes.
• Epigenetic Alterations: Changes in gene expression that do not involve changes to the underlying DNA sequence.
• Loss of Proteostasis: The failure of cellular machinery to maintain healthy protein function.
• Mitochondrial Dysfunction: A decline in the energy-producing efficiency of cells.
• Cellular Senescence: The accumulation of cells that have stopped dividing but do not die, often releasing inflammatory signals.

Knowns vs. Unknowns

While we have identified these mechanisms, much remains unknown.

• Driver vs. Passenger: It is often unclear which changes are the causes of ageing and which are merely consequences of it.
• Interconnectivity: These hallmarks are deeply interconnected; affecting one often influences others.
• Translation to Humans: Much of our current understanding comes from short-lived model organisms like yeast, worms (C. elegans), and mice. Translating these findings to human biology is a complex and ongoing challenge.