Exerkines in diabetic retinopathy: from mechanisms to therapeutic prospects.

Diabetic retinopathy (DR) is a leading cause of vision loss worldwide, driven by chronic metabolic dysregulation that promotes inflammation, oxidative stress, and progressive neurovascular unit dysfunction in the retina. While regular exercise is an effective non-pharmacological strategy to reduce diabetes-related complications, accumulating evidence suggests that its retinal benefits extend beyond systemic metabolic control and are mediated in part by exercise-induced bioactive factors known as exerkines. Secreted from skeletal muscle, adipose tissue, liver, and other organs, exerkines act as endocrine signals linking physical activity to tissue-specific adaptations. This review provides a retina-focused, cell-type-oriented synthesis of current evidence implicating key exercise-responsive exerkines, including irisin, adiponectin, brain-derived neurotrophic factor, fibroblast growth factor-21, apelin, and clusterin, in pathways relevant to DR pathogenesis. We systematically map reported exerkine actions to retinal endothelial cells, pericytes, Müller glia, microglia, neurons, and the retinal pigment epithelium, while explicitly distinguishing findings from retinal or DR-specific models from those extrapolated from extra-ocular systems. We further integrate emerging data on exercise modality-specific exerkine signatures and discuss their translational relevance, limitations, and safety considerations across different stages of DR. In total, this review highlights exerkines as candidate mediators and biomarkers of exercise-retina crosstalk and outlines priorities for mechanistic validation and clinical translation alongside established therapies such as anti-VEGF treatment.