The Influence of SGLT2 Inhibitors on the Immune System and Inflammatory Processes in Kidney Transplantation

Kidney transplantation (KT) remains the optimal therapy for end-stage kidney disease (ESKD), yet long-term graft survival is limited by unremitting allograft dysfunction and non-immune treatment toxicities. Sterile inflammation primarily drives graft failure. This inflammatory process releases damage-associated molecular patterns (DAMPs). DAMPs activate pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs) 2 and 4, from proximal tubule epithelial cells, endothelial compartments, and infiltrating myeloid lineages. PRR signaling and the release of pro-inflammatory cytokines (IL-1β, IL-18, TNF-α) promote pro-inflammatory M1 macrophage polarization and accelerate interstitial fibrosis and tubular atrophy (IFTA). While maintenance immunosuppression prevents adaptive rejection, it causes severe metabolic, cardiovascular, and oncologic complications, including post-transplant diabetes mellitus, hypertension, and malignancies. Sodium-glucose cotransporter 2 (SGLT2) inhibitors (dapagliflozin, empagliflozin, canagliflozin) have emerged as novel disease-modifying, immunomodulatory adjuncts that act independently of glycemic control. SGLT2 inhibition reactivates tubuloglomerular feedback to relieve intraglomerular hypertension, blunts hyperfiltration, and reduces tubular transport workload. This alleviates cortical hypoxia, curtails mitochondrial ROS production, and activates AMP-activated protein kinase (AMPK) to suppress NF-κB and NLRP3 inflammasome assembly. SGLT2 inhibitors downregulate TLR expression, drive a phenotypic shift toward reparative M2 macrophages, reduce proteinuria, and provide sustained volume decongestion without triggering compensatory activation of the renin-angiotensin-aldosterone system. By targeting both upstream bioenergetic strain and downstream fibrotic remodeling (YAP/TAZ axis), SGLT2 inhibitors complement standard immunosuppression to protect allograft architecture, reduce cardiovascular morbidity, and improve long-term transplant outcomes.