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Reference

Glossary of aging science

Plain-language definitions of the terms you’ll meet across the record. These also appear as hover-definitions while you read.

Autophagy
The cell's recycling process that breaks down and reuses damaged components; declines with age.
Caloric restriction
Reducing calorie intake without malnutrition; one of the most reproducible lifespan-extending interventions in animals.
Epigenetic clock
A method that estimates biological age from DNA methylation patterns.
Hallmarks of aging
A canonical set of interconnected biological processes that drive aging (e.g. genomic instability, telomere attrition, cellular senescence).
Healthspan
The period of life spent in good health, free of chronic disease and disability — distinct from total lifespan.
Inflammaging
Chronic, low-grade inflammation that increases with age and contributes to many age-related diseases.
Mitochondrial dysfunction
Age-related decline in the cell's energy-producing organelles, a hallmark of aging.
mTOR
A central nutrient-sensing signaling pathway; its inhibition (e.g. by rapamycin) extends lifespan in many organisms.
NAD+
A coenzyme central to cellular energy metabolism whose levels decline with age.
Partial reprogramming
Briefly expressing reprogramming factors (e.g. OSK) to rejuvenate cells without erasing their identity.
Proteostasis
The maintenance of a healthy, correctly-folded set of proteins in a cell; loss of proteostasis is a hallmark of aging.
Rapamycin
An mTOR-inhibiting drug studied for extending healthspan and lifespan.
Senescence
A state in which a cell permanently stops dividing but does not die, often secreting inflammatory signals; accumulation of senescent cells is a hallmark of aging.
Senolytics
Drugs or compounds that selectively clear senescent ("zombie") cells from tissues.
Telomere
A protective cap of repetitive DNA at the end of a chromosome that shortens with each cell division.