Fluorofenidone attenuates diabetic nephropathy and kidney fibrosis in db/db mice

Fluorofenidone [1-(3-fluorophenyl)-5-methyl-2-(1H)-pyridone, AKF-PD], a novel pyridone agent, showed potent antifibrotic properties. The aim of the present study was to investigate the effects of AKF-PD on diabetic nephropathy and kidney fibrosis, and to obtain an insight into its mechanisms of action.

We administered AKF-PD to diabetic db/db mice for 12 weeks. Moreover, we performed in vitro cultures using murine mesangial cells exposed to high ambient glucose concentrations.

AKF-PD reduced renal hypertrophy, mesangial matrix expansion and albuminuria in the db/db mice. The upregulated expression of α₁(I)- and α₁(IV)-collagen and fibronectin mRNAs, transforming growth factor-β1 (TGF-β₁), α-smooth muscle actin (α-SMA), and tissue inhibitors of metalloproteinase 1 (TIMP-1) mRNAs and proteins was inhibited by AKF-PD treatment in the renal cortex of db/db mice. The maximal effective dose of AKF-PD was about 500 mg/kg body weight. AKF-PD inhibited the upregulated expression of α₁(I)- and α₁(IV)-collagens, TGF-β₁, TIMP-1 and α-SMA induced by high glucose concentrations in cultured mesangial cells.

Our data indicate that AKF-PD diminishes the abnormal accumulation of mesangial matrix through the inhibition of upregulated expression of TGF-β target genes in kidneys of db/db mice, resulting in attenuation of renal fibrosis and amelioration of renal dysfunction despite persistent hyperglycemia. Therefore, AKF-PD, a potent antifibrotic agent, holds great promise in the treatment of diabetic nephropathy.