Définition
Autophagy is the cellular self-cleaning process by which cells identify, dismantle, and recycle damaged proteins and organelles. It is a critical longevity mechanism — the body's internal quality-control system — and is activated by fasting, exercise, and caloric restriction.
The word autophagy comes from Greek, meaning "self-eating." It was characterized in detail by Japanese scientist Yoshinori Ohsumi, who won the Nobel Prize in Physiology or Medicine in 2016 for this work. The process involves the sequestration of damaged cellular material into a double-membrane vesicle (autophagosome), which then fuses with a lysosome to degrade and recycle the contents.
Autophagy serves multiple longevity functions: it removes misfolded and aggregated proteins whose accumulation drives neurodegeneration, clears dysfunctional mitochondria (mitophagy), and recycles cellular components during nutrient scarcity to maintain essential functions. It also has immune functions — clearing intracellular pathogens — and regulates inflammation by controlling the secretion of inflammatory cytokines.
Autophagy is suppressed by nutrient availability — particularly insulin and the mTOR signaling pathway — and activated by nutrient scarcity via AMPK. This is why fasting, caloric restriction, and time-restricted eating are associated with autophagy induction. Aerobic exercise activates autophagy via AMPK signaling. Coffee (caffeine), spermidine (from wheat germ and aged cheese), and sulforaphane from broccoli sprouts have evidence for mild autophagy induction through distinct pathways.
Termes associés
Ava Longevity · Built on the Ava Method · MMXXV