Fluorofenidone Attenuates Renal Interstitial Fibrosis by Enhancing Autophagy and Retaining Mitochondrial Function

Cell Biochem Biophys. 2023 Dec;81(4):777-785. doi: 10.1007/s12013-023-01176-7. Epub 2023 Sep 21.

Abstract

Background: Fluorofenidone (AKF-PD) is a novel pyridone agent and has potent anti-NLRP3 inflammasome and anti-fibrotic activities. However, the mechanisms underlying its pharmacological actions are not fully understood.

Methods: A renal fibrosis rat model was established by the unilateral ureteral obstruction (UUO) procedure and the rats were randomized and treated with, or without, AKF-PD for 3 and 7 days. The levels of renal fibrosis, NLRP3 inflammasome activation, mitochondrial function, and autophagy were tested in rat kidney tissues. Macrophages following lipopolysaccharides (LPS) and adenosine 5'-triphosphate (ATP) stimulation were examined by Western blot, spectrophotometry, and TEM.

Results: Compared with the untreated UUO rats, AKF-PD treatment significantly mitigated the UUO procedure-induced renal fibrosis in rats. AKF-PD treatment decreased mitochondrial dysfunction and IL-Iβ and caspase-1 expression in rat kidney tissues and reduced mitochondrial reactive oxygen species production in activated macrophages. Mechanistically, AKF-PD treatment significantly attenuated the PI3K/AKT/mTOR signaling, increased Beclin-1 and LC3 II expression and autophagosome formation, and ameliorated the mitochondrial damage in renal tissues and activated macrophages.

Conclusion: The results indicated that AKF-PD treatment inhibited renal interstitial fibrosis by regulating the autophagy-mitochondria-NLRP3 inflammasome pathway.

Keywords: AKF-PD; Autophagy; Mitochondrial dysfunction; NLRP3 inflammasome; Renal interstitial fibrosis.

MeSH terms

  • Animals
  • Autophagy
  • Fibrosis
  • Inflammasomes / metabolism
  • Kidney Diseases* / drug therapy
  • Mitochondria / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Phosphatidylinositol 3-Kinases
  • Pyridones / pharmacology
  • Pyridones / therapeutic use
  • Rats
  • Rats, Sprague-Dawley
  • Ureteral Obstruction* / complications
  • Ureteral Obstruction* / drug therapy
  • Ureteral Obstruction* / metabolism

Substances

  • 5-methyl-1-(3-fluorophenyl)-2-(1H)-pyridone
  • Inflammasomes
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Phosphatidylinositol 3-Kinases
  • Pyridones