SGLT2 Inhibition Ameliorates Age-Dependent Renovascular Rarefaction
IntroductionAging is associated with progressive loss of renal function and vascular structure, with and without chronic kidney disease. However, the mechanisms driving renal vascular aging and potential therapeutic interventions remain poorly understood. MethodsTo model this state-of-affairs, we used African turquoise killifish (Nothobranchius furzeri), a naturally short-lived vertebrate. We then inhibited the sodium-glucose co-transporter 2 using dapagliflozin (SGLT2i) to test a potential therapeutic intervention. Histological, immunofluorescent, and 3D vascular imaging were used to evaluate glomerular, tubular, vascular and functional changes. Single-nuclei transcriptomic profiling was performed on whole kidneys to identify age- and treatment-associated molecular signatures. ResultsAged killifish kidneys exhibited hallmark features of renal aging, including glomerulosclerosis, tubular fibrosis, and vascular rarefaction. Functional changes included increased proteinuria and altered tubular transporter function. Transcriptomic profiling revealed a metabolic shift from oxidative phosphorylation to glycolysis and upregulation of pro-inflammatory pathways. Aged vasculature also displayed a marked reduction in tight junctions and cell-cell contacts. SGLT2i attenuated age-related vascular rarefaction, preserved functional capillary networks, reduced albuminuria, restored a youthful transcriptional profile and enhanced intercellular signaling. However, killifish lifespan was not extended. ConclusionThis study establishes the killifish as a translational model for investigating renal vascular aging. We show that SGLT2i preserves renal microvascular structure and function, reduces proteinuria, and reprograms the aged transcriptome. These results support a vascular-protective role of SGLT2i in mitigating age-related renal deterioration. Translational StatementThis study establishes the African turquoise killifish as a model for investigating renal and vascular aging. We found that SGLT2 inhibition preserves microvascular integrity and reduces proteinuria. These results mirror established benefits observed in mammalian models and patients with chronic kidney disease, reinforcing the kidney-protective role of SGLT2 inhibitors. However, the killifish offers a unique opportunity for rapid, translational aging research. By using a naturally short-lived vertebrate with mammalian-like renal aging, our model enables a rapid, preclinical, assessment of vascular outcomes and identifies microvascular preservation as a potential mechanistic target for renoprotection.