Single-Cell Maps Reveal Novel Mechanisms of Ferroptosis and Biomarkers in Diabetic Nephropathy

OBJECTIVE: Diabetic nephropathy (DN) is the main cause of renal failure due to its complexity and difficulty in prevention. The purpose of our study is to screen potential biomarkers of DN at the single-cell level and reveal its new molecular pathogenesis by single-cell RNA sequencing (scRNA-seq). METHODS: In this study, scRNA-seq was performed on kidney tissue of control and DN mice. Through multiple analyses of the data, biomarkers in DN that contribute to early diagnosis were screened, and the complex pathogenesis associated with ferroptosis was revealed and verified by experiments at the animal and cellular levels. RESULTS: Through customized analysis of scRNA-seq results, we found for the first time increased intercellular communication between mesangial epithelial cells and transitional epithelial cells in the pathological state of DN. In addition, two sets of differential protein interaction analysis networks showed that Eno1, Hspa8, FLT1, Hspa1a, and Gsta2 could be used as predictive biomarkers of DN. Finally, the promoting effects of ferroptosis, heat shock protein and their interactions in the development of DN are discussed. In particular, the regulation of GPX4 by members of the heat shock family, Dnaja1 and Hspa1a, promotes lipid peroxidation (the classic phenotype of ferroptosis). DISCUSSION: We identified disruption of iron homeostasis and activation of the ferroptosis pathway, alongside differential expression of oxidative stress-related genes, including PGAM2. Heat shock proteins (e.g., Hspa1a, Dnaja1) were found to interact with ferroptosis markers (e.g., GPX4), suggesting a chaperone-mediated protective mechanism under diabetic stress. Analogous to the Flory-Huggins solution theory, HSPs may enhance misfolded protein compatibility in the cytosol, reducing aggregation. This study provides insight into HSP-regulated ferroptosis in DN, though further validation is required for clinical translation. CONCLUSION: In conclusion, we comprehensively analyzed the relevant biomarkers and pathogenesis of DN at single-cell resolution, providing new strategies for therapeutic targets of the disease.