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FGF21

Hepatokine induced by protein restriction, fasting, and amino acid imbalance that signals nutrient stress to the brain (increasing food and protein appetite) and adipose tissue (increasing energy expenditure and insulin sensitization).

Also: Fibroblast growth factor 21

FGF21 is induced via the integrated stress response (ATF4) under amino acid restriction and via PPARα under fasting. It contributes to the metabolic benefits of dietary restriction independent of weight loss. FGF21 levels are paradoxically elevated in obesity and NAFLD (a state of FGF21 resistance). Pharmacologic FGF21 analogs are in development for NASH.

How one textbook covers it

  • Modern Nutrition in Health and Disease, 12th ed. — Ch 51: Metabolic and Molecular Consequences of Dietary Restriction

    FGF21 is induced via the integrated stress response (ATF4) under amino acid restriction and via PPARα under fasting. It contributes to the metabolic benefits of dietary restriction independent of weight loss. FGF21 levels are paradoxically elevated in obesity and NAFLD (a state of FGF21 resistance). Pharmacologic FGF21 analogs are in development for NASH.

Related terms

Caloric restriction, NAFLD, Protein restriction