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bioRxiv · 10.1101/2023.11.13.566898

Metabolic Reprogramming of the Neovascular Niche Promotes Regenerative Angiogenesis in Proliferative Retinopathy

Abstract

Healthy blood vessels supply neurons to preserve metabolic function. In blinding ischemic proliferative retinopathies (PRs), pathological neovascular tufts often emerge in lieu of needed physiological neuroretina revascularization. We show that metabolic shifts in the neurovascular niche define this angiogenic dichotomy between healthy and diseased blood vessel growth. Fatty acid oxidation (FAO) metabolites accumulated in human and murine retinopathy samples. Neovascular tufts with a distinct single-cell transcriptional signature highly expressed FAO enzymes. The deletion of Sirt3, an FAO regulator, shifted the neurovascular niche metabolism from FAO to glycolysis and suppressed tuft formation. This metabolic transition increased Vegf expression in astrocytes and reprogrammed pathological EC to a physiological phenotype, hastening vascular regeneration of the ischemic retina. Our findings identify SIRT3 as a metabolic switch in the neurovascular niche, offering a new therapeutic target for optimizing ischemic tissue revascularization. HighlightsO_LIPathological EC favor FAO over glycolysis. C_LIO_LIUnique signature for pathological EC found in proliferative retinopathy model. C_LIO_LISirt3 deletion shifts astrocytes and EC metabolism from FAO to glycolysis. C_LIO_LIMetabolic reprogramming of the vascular niche enhances physiological revascularization. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/566898v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@70020eorg.highwire.dtl.DTLVardef@19719acorg.highwire.dtl.DTLVardef@1168ddeorg.highwire.dtl.DTLVardef@1bc25e0_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Cagnone, G., Pundir, S., Sung-Kim, J., Rivera, J. C., Agnihotri, T., Harvey, N.-R., Heckel, E., Betus, C., Chen, M. X., Situ, A., Gaub, P., Kim, N., Das, A., Leclerc, S., Wunnemann, F., Andelfinger, G., Crespo-Garcia, S., Dubrac, A., Rezende, F., Clish, C. B., Maranda, B., Smith, L. E. H., Sapieha, P., Joyal, J.-S.. 2023-11-13. Metabolic Reprogramming of the Neovascular Niche Promotes Regenerative Angiogenesis in Proliferative Retinopathy. https://doi.org/10.1101/2023.11.13.566898

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