Influence of zinc levels on clinical and inflammatory factors, and renal prognosis in patients with diabetic nephropathy

Abstract

Abstract Background/Objectives: Our study aimed to investigate the correlation of plasma zinc (Zn)with tumor necrosis factor-α (TNF-α), non-classical nuclear factor-κB (NF-κB), and nuclear factor erythroid 2-related factor 2 (Nrf2) in patients with diabetic nephropathy (DN༉and explored the potential impact of Zn levels on clinical, inflammatory responses and renal prognosis in DN patients. Subjects/Methods: We selected 45 patients who were definitively diagnosed with DN by renal biopsy in our hospital from 2019 to 2021, and recruited 25 healthy individuals from the physical examination center as controls. The correlation between Zn and serum Nrf2, TNF-α, and NF-κB levels were assessed using Spearman's rank correlation coefficient. In addition, patients were further divided into low- and high-Zn groups to observe the differences in clinical indicators, identify the expression of inflammatory-related factors in renal tissue. The Kaplan–Meier method was used to draw survival curves to predict the impact of related indicators on renal prognosis. Results We found that blood Zn and Nrf2 levels in patients with DN were significantly lower, while TNF-α, and NF-κB levels were significantly higher than those in patients without DN. Zn correlated positively with Nrf2 levels and negatively with TNF-α and NF-κB levels. In addition, patients with high Zn levels had higher expression of Nrf2, and lower expression levels of TNF-α and NF-κB in renal tissue, and had better prognosis compared with patients with low Zn levels. Conclusions We demonstrated that Zn had a protective effect on DN, and it may affect the inflammatory response.