Lactate Signaling and Lactylation in Retina: From Physiological Warburg Effect to Pathological Metabolic Reprogramming.
Lactate was once regarded merely as a byproduct of glycolysis, but is now recognized as a multifunctional metabolite that coordinates energy redistribution, intercellular communication, receptor-mediated signaling, and epigenetic regulation. In the retina, these functions are especially consequential because visual processing depends on a highly specialized and energetically demanding tissue, characterized by steep oxygen gradients, a dual vascular supply, and tightly integrated metabolic crosstalk among photoreceptors (PCs), Müller glia, the retinal pigment epithelium, vascular cells, and retinal ganglion cells. In this review, we synthesize current advances in lactate signaling and lactylation in the retina, and examine how their dysregulation contributes to neovascularization, inflammation, and neurodegeneration in disorders including diabetic retinopathy, age-related macular degeneration, autoimmune uveitis and glaucoma. Drawing from these metabolic insights, therapeutic interventions targeting lactate signaling and lactylation are discussed as potential approaches to mitigate retinal abnormalities. Collectively, this review highlights the central importance of lactate signaling and lactylation in retinal physiology and pathology, and provides a conceptual framework for developing metabolic interventions aimed at restoring retinal lactate homeostasis.