Abstract: TH-PO0326
Untargeted Single Glomerulus Proteomics Reveals Sex-Specific Aging States
Session Information
- Glomerular Diseases: Omics
October 22, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1401 Glomerular Diseases: Mechanisms, including Podocyte Biology
Authors
- Hsu, Chris, University of Washington, Seattle, Washington, United States
- Ruiz Sanchez, Carla, University of Washington, Seattle, Washington, United States
- Sweetwyne, Mariya T., University of Washington, Seattle, Washington, United States
- Maccoss, Michael, University of Washington, Seattle, Washington, United States
Background
Kidney aging is marked by heterogeneous accumulation of glomerulosclerosis, but bulk glomerular proteomics obscures variation between glomeruli within kidneys and between individuals. Single glomerulus proteomics could resolve this heterogeneity but has been limited by poor sensitivity at low protein input. We applied recent advances in mass spectrometry to test whether heterogeneity of proteomics states could be resolved at the single glomerulus level.
Methods
20-30 single glomeruli were randomly selected from bulk glomerular isolates of young (6 mo, n=4/sex) and aged (24 mo, n=6/sex) C57BL/6 mice. Whole kidneys and pooled glomeruli from each animal served as enrichment controls. Samples were measured using an Orbitrap Astral Zoom mass spectrometer coupled to an EvoSep LC system. Protein abundances were analyzed for glomerular enrichment, inter-glomerular heterogeneity, and age/sex differences using linear modeling, PCA/pseudotime, GO enrichment, and network analyses.
Results
We quantified 8,921 proteins across 532 glomeruli from 20 mice, averaging 5,706 per glomerulus, comprising potentially the largest single glomerulus proteomics studies to date. We observed inter-glomerular variation within mice and an aging-associated proteomic state present in different fractions of glomeruli across aged animals that were obscured in bulk samples. Pseudotime and differential abundance analyses identified age-associated remodeling in both sexes, but young-old contrasts were larger in females. We identified 983 aging-associated proteins in females and 240 in males (800 female-only, 57 male-only, 183 shared). Broadly, enriched pathways overlapped with known kidney aging and injury programs but single glomerular analyses revealed their variable prevalence across glomeruli, mouse, age, and sex. Immune/complement pathways were increased in age for both sexes but most clearly resolved in females. In aged female glomeruli, upregulated proteins also enriched for wound healing, and matrix remodeling pathways while downregulated proteins were found in podocyte and glomerular structural support pathways.
Conclusion
Single glomerulus proteomics resolves inter-glomerular variation and age- and sex-associated remodeling not captured by bulk profiling. In depth analysis of this extensive data set is ongoing, but early results support a model in which aged female glomeruli show more prominent immune and injury-repair remodeling.