Figure 1

Impact of insulin/IGF-1 signaling in Laron syndrome (A) and Western diet (B) on FoxO-mediated gene regulation and associated pathologies. GHR*, growth hormone receptor loss of function mutation in Laron syndrome; GIP, glucose-dependent insulinotropic polypeptide, a whey protein-induced incretin, which stimulates β-cell proliferation and insulin secretion; PRL, prolactin; PRL secretion is induced by serotoninergic hypothalamic signaling; Trp, tryptophan, and Leu, leucine, essential amino acids enriched in the whey protein α-lactalbumin; Trp via serotonin synthesis stimulates pituitary GH and PRL secretion and Leu stimulates β-cell proliferation and insulin secretion.