Transforming Growth Factor-β in the Acute Kidney Injury to Chronic Kidney Disease Transition

Transforming growth factor-β (TGF-β) is a key profibrotic growth factor that is activated in acute kidney injury (AKI) and associated with cellular responses that lead to the development of chronic kidney disease (CKD). The persistently injured, de-differentiated tubular epithelial cell is an important mediator of the transition from AKI to CKD. TGF-β signaling may perpetuate proximal tubule injury through de-differentiation, cell cycle arrest, and increased susceptibility to apoptosis. In addition, TGF-β signaling promotes macrophage chemotaxis, endothelial injury, and myofibroblast differentiation after AKI. Future studies that block TGF-β signaling after cessation of AKI are needed to better define its role in the progression of acute to chronic renal injury.