HDAC9 and renal fibrosis: Studies done in the unilateral ureteral obstruction (UUO) model have shown that treatment with various HDAC inhibitors, such as trichostatin A or the selective class I HDAC inhibitor MS-275, reduced renal fibrosis by diminishing profibrotic markers (α-smooth muscle actin (SMA)) and accumulation of ECM proteins, including fibronectin and type I collagen [60–63].