AGEs–RAGE Axis and Mitochondrial-Derived Peptides in Advanced Chronic Kidney Disease: Interconnected Pathways Beyond Inflammation and Nutrition

Background. Chronic kidney disease [CKD] is characterized by increased glycoxidative stress, inflammation, and mitochondrial dysfunction. Advanced glycation end-products [AGEs] and their receptor [RAGE] mediate glycoxidative stress, whereas mitochondrial-derived peptides [MDPs], including humanin [HN], MOTS-c, and humanin-like 1 [HN-L1], regulate mitochondrial stress responses. We investigated links between AGE–RAGE activation and mitochondrial signaling in CKD. Methods. Serum AGEs, soluble RAGE isoforms, and MDPs were measured by ELISA in 160 adults with kidney failure undergoing living-donor kidney transplantation and in 80 controls, Results. CKD patients showed higher AGEs and esRAGE, lower AGEs/sRAGE ratios, and reduced MDPs. AGEs correlated positively with sRAGE, cRAGE, and HN, while MOTS-c was inversely associated with AGEs and the AGEs/sRAGE ratio. In multivariable analyses, HN remained independently associated with AGEs, sRAGE, and the AGEs/sRAGE ratio, whereas MOTS-c showed an inverse association with the AGEs/sRAGE ratio. CRP was associated with the AGEs/sRAGE ratio while PEW showed no associations with AGEs–RAGE components or MDP. Conclusions. CKD is characterized by increased glycoxidative stress and reduced MDPs, reflecting altered mitochondrial stress signaling. AGEs–RAGE and MDPs are biologically linked, suggesting partially overlapping but distinct pathophysiological pathways.