Previous studies have demonstrated that induction of HO-1 with hemin reduced the overexpression of osteopontin and TGF-β, the hallmarks of tubulointerstitial injury in salt-sensitive angiotensin II hypertension suggesting a role of HO-1 induction against renal fibrosis in hypertension [36]. This evidence concerns the gene TGFB1 and renal fibrosis.