Integrative transcriptomic and single-cell analyses identify CD74 as a candidate regulator of ferroptosis in renal tubular cells during nephrolithiasis

Abstract

Abstract Nephrolithiasis incidence has risen with frequent recurrence, and injury to renal tubular epithelial cells is central to its pathology. Ferroptosis, an iron-dependent form of regulated cell death, has been implicated in kidney diseases, but its role in nephrolithiasis remains unclear. In this study, we investigated whether CD74 is associated with ferroptosis-related tubular injury during nephrolithiasis and explored the potential involvement of NF-κB signaling. A glyoxylate-induced mouse model showed prominent calcium oxalate deposition, impaired renal function, altered expression of ACSL4 and GPX4, and increased oxidative stress. Integrating bulk transcriptomics, protein–protein interaction networks, bioinformatics, and a public single-cell RNA-sequencing dataset, we identified CD74 as a candidate ferroptosis-associated gene showing increased expression during nephrolithiasis progression. In vitro, oxalate exposure in human HK-2 cells induced CD74 upregulation together with ferroptosis-associated molecular and biochemical changes. CD74 knockdown improved cell viability and redox homeostasis and attenuated ferroptosis-associated marker changes, whereas CD74 overexpression aggravated oxidative injury and ferroptosis. Mechanistically, CD74 modulation was associated with changes in NF-κB signaling activity, and pharmacological modulation of NF-κB partially reversed the corresponding cellular phenotypes. Together, these findings support a potential role of CD74-associated NF-κB signaling in ferroptosis-related tubular injury during nephrolithiasis. These findings suggest that the CD74/NF-κB axis may represent a potential therapeutic direction and provide mechanistic insight for future studies.