Contrasting effects of steroids and mizoribine on macrophage activation and glomerular lesions in rat Thy-1 mesangial proliferative glomerulonephritis

Contrasting Effects of Steroids and Mizoribine on Macrophage Activation and Glomerular Lesions in Rat Thy-1 Mesangial Proliferative Glomerulonephritis. Background: Macrophages with a pro-inflammatory (M1) phenotype mediate renal injury in proliferative forms of glomerulonephritis, while alternatively activated (M2) macrophages are thought to be anti-inflammatory and promote repair. Glucocorticoids, the mainstay therapy for proliferative glomerulonephritis, can induce alternative macrophage activation in vitro, but it is unknown whether this occurs in vivo and if this is required for glucocorticoid responsiveness. In addition, clinical studies have suggested that the ability of mizoribine (MZR) to suppress steroid-resistant proliferative glomerulonephritis may operate via inhibiting pro-inflammatory macrophage activation.