Urine extracellular vesicles capture kidney transcriptome and hyperglycemia linked mRNA signatures for type 1 diabetic kidney disease

Diabetic kidney disease (DKD) is a severe complication of type 1 diabetes (T1D), which lacks non-invasive early biomarkers. Although less explored, mRNAs in urinary extracellular vesicles (uEV) could reflect changes in the kidney transcriptome during DKD development. We performed genome-wide mRNA sequencing of >100 uEV samples from two T1D cohorts with 24-hour and overnight urine collections. Our uEV pipeline allowed reproducible detection of >10,000 mRNAs bearing overall similarity to kidney transcriptome. uEV from T1D DKD groups showed significant upregulation of 13 genes, prevalently expressed by proximal tubular cells within the kidney. Strikingly, six genes involved in cellular stress responses including protection against oxidative stress (GPX3, NOX4, MSRB, MSRA, HRSP12 and CRYAB) correlated with hyperglycemia and long-term changes in kidney function independent of albuminuria status. The study identified genes associated with glycemic stress in T1D DKD and confirmed the utility of uEV in capturing pathological gene expression signatures from kidney.