Fat Tissue Controls Lifespan Through Insulin Signaling in Fruit Flies
In fruit flies, dialing down a gene called Dicer-1 in fat tissue extended lifespan. It worked even when flies were already on calorie restriction. The mechanism involves a chain reaction: lower Dicer-1 reduces a small RNA molecule in fat, which boosts a hormone that then tells the brain to release less insulin. Less insulin signaling is a well-known longevity pathway across species.
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