Changes in Urine Proteome After Living Kidney Donation: A Prospective Cohort Study

Background Kidney transplantation, especially from a living donor, is the best treatment for patients with end-stage kidney disease (ESKD). Compared to healthy non-donors, kidney donors have shown a higher incidence of ESKD, increased long-term risk for cardiovascular and all-cause mortality, although the absolute risk is small. In this study, we explored the changes in the urinary proteome after living kidney donation and their possible association with renal adaptations in kidney donors. Materials and Methods Voluntary kidney donors aged >18 years were enrolled in the study. Proteomic analysis of urine samples from the study subjects at baseline and 6-month follow-up was performed using liquid chromatography-mass spectrometry (LC-MS). Results 20 out of 25 enrolled subjects completed 6 6-month follow-ups. Mean eGFR significantly reduced at follow-up (106 to 80 mL/min/1.73m 2 ). eGFR reached ∼76% of the pre-donation value. We identified 350 differentially expressed proteins (DEPs), of which 149 were upregulated and 201 were downregulated after kidney donation. Gene ontology enrichment analysis shows that these DEPs are involved in various molecular, biological functions and pathways. Conclusion The study identifies potential biological processes and pathways involved in adaptation following unilateral nephrectomy. These observations require confirmation and validation.