Single nucleus RNA sequencing reveals cellular and molecular responses to vanadium exposure in duck kidneys.

Vanadium (V) exposure is known to induce renal toxicity, yet its specific effects on renal cell types and molecular mechanisms remain incompletely understood. We used single nucleus RNA sequencing (snRNA-seq) to characterize the impact of V on duck kidney cells at a cellular resolution. Following a 44-day exposure, immunofluorescence analysis revealed a significant increase in α-SMC expression in the renal interstitium, indicative of fibrotic response. SnRNA-seq identified 12 major cell types organized into 19 clusters within the kidney. Significant changes in cell composition were observed, notably an increase in proximal tubule cells (PT2 subtype), glomerular endothelial cells, principal cells, and alterations in immune cell proportions, while collecting duct intercalated cells (CD-IC) and thick ascending limb showed decreased percentages. Differential gene expression analysis highlighted pathways implicated in V toxicity across different cell types. Changes in drug metabolism-cytochrome P450, butanoate metabolism, and actin cytoskeleton regulation were exhibited by PT cells. Alterations in collecting duct secretion, oxidative phosphorylation, and bicarbonate reclamation pathways were shown in CD-IC cells. Furthermore, immune cells displayed changes in T cell receptor and chemokine signaling pathways, indicative of altered immune responses. Taken together, these findings contribute to a better shedding light on the pathogenic mechanisms of V induced renal injury.