HDAC4 and renal fibrosis: To specifically determine the role of HDAC4 in the development of renal fibrosis and assess the therapeutic effect of HDAC4 inhibition, we established a mouse model of the UUO-induced renal interstitial fibrosis and then injected tasquinimod 24 h via I.P after surgery, followed by daily injections for 6 constitutive days.