We show that the retinal pigment epithelium (RPE) — the outermost layer of the retina — is a local source of insulin that is modulated by starvation and phagocytosis, separate from pancreatic insulin. Further, this RPE-derived insulin has functional relevance in retinal physiology, retinal metabolic homeostasis and in limiting retinal disease.
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This is a summary of: Etchegaray, J. I. et al. Phagocytosis in the retina promotes local insulin production in the eye. Nat. Metab. https://doi.org/10.1038/s42255-022-00728-0 (2023).
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A local source of insulin protects the retina against starvation. Nat Metab 5, 205–206 (2023). https://doi.org/10.1038/s42255-023-00745-7