Abstract

Objective: This study aimed to determine the Glucagon-like peptide-1 receptor (GLP-1R) and angiotensin converting enzyme (ACE) inhibitor pathways across the renal compartment.
Methods: A spatially resolved single-cell RNA sequencing method was developed. This approach included better dissociation techniques for the tubulointerstitial and glomerular compartments with the Visium Spatial Gene Expression platform. To account for regional variation, GLP-1R receptor activity was assessed using downstream effectors and contrasted with the fibrosis-inhibitory effects of ACE inhibitors using weighted pathway scores. Lipid peroxidation vulnerability was also estimated in a ferroptosis resistance module, which is particularly relevant for GLP-1 receptor agonists modified with fatty acids. A machine-learning pipeline was applied to process spatial transcriptomic profiles, which were compared with clinical variables such as estimated glomerular filtration rate and urine albumin-to-creatinine ratio.
Results: While ACE inhibitors showed strong glomerular suppression of Renin-Angiotensin-Aldosterone System-Transforming Growth Factor-beta (RAAS-TGF)-small intestine pathways, GLP-1RAs demonstrated high tubular stimulation of Cyclic Adenosine Monophosphate, Protein Kinase A (PKA), and cAMP Response Element-Binding protein (cAMP-PKA-CREB) pathways and enhanced ferroptosis resistance. Using spatial-clinical modeling, hotspots of therapy were non-overlapping, geographically discontinuous, and highly consistent with pathway activation and results in renal treatment.
Conclusion: The reno protective effects of GLP-1RAs and ACE inhibitors in DN were mediated by complementary microenvironment-specific mechanisms that confer tubular cryoprotection against glomerular antifibrosis. In the field of precision nephrology, spatial transcriptomics supports a microenvironment-focused treatment approach and serves as a powerful mechanism for comparative mechanistic analysis.

Key words: Diabetic nephropathy, GLP-1 receptor, ACE inhibitor, spatial transcriptomics, single-cell RNA sequencing, ferroptosis; renal microenvironment; precision nephrology.