Hepatoprotective effect of Baicalin against thioacetamide-induced cirrhosis in rats: Targeting NOX4/NF-κB/NLRP3 inflammasome signaling pathways

Life Sci. 2022 Apr 15:295:120410. doi: 10.1016/j.lfs.2022.120410. Epub 2022 Feb 17.

Abstract

Aim: Liver cirrhosis is the result of a vicious cycle of both chronic oxidative stress and inflammation. NADPH oxidase-4 (NOX4) and its companion, NOD-like receptor protein 3 (NLRP3) inflammasome, are emerging as therapeutic targets of liver fibrosis.

Main methods: Baicalin (BA), a natural flavone, has been investigated for its therapeutic potential against cirrhosis induced by thioacetamide (TAA) (200 mg/kg, twice/week) for 12 weeks in Sprague-Dawley rats. Two doses of BA were administered (25 and 75 mg/kg/day, orally, a week after TAA was stopped and continued for 4 weeks).

Key findings: BA was able to reduce fibrosis visualized by Masson trichrome and immunohistochemical staining of the hepatic α-smooth muscle actin (α-SMA) and transforming growth factor-β1. Moreover, BA was able to ameliorate inflammation by reducing hepatic NLRP3 inflammasome subunits, NLRP3 and caspase-1, both parts of the complex responsible for the activation of different interleukins (IL), measured as IL-1β. In addition, BA was able to reduce hepatic nuclear factor kappa B (NF-κB)-driven inflammation through IL-6. BA targeted inflammation through its anti-oxidant ability evidenced by the enhancement of the hepatic superoxide dismutase (SOD) and reduced glutathione (GSH) activity and level, respectively, and the reduction of both hepatic malondialdehyde (MDA) and nitric oxide (NOx) contents. Treatment with BA significantly decreased TAA-induced elevation in hepatic NOX4, a key enzyme for reactive oxygen species (ROS) generation, as well as, inducible nitric oxide synthase (iNOS).

Significance: therefore, the study could conclude, the anti-fibrotic effect of BA through TGF- β1/NOX4/NF-κB/NLRP3 pathway, exerting both anti-inflammatory and anti-oxidant effects.

Keywords: Anti-fibrotic; Baicalin; NF-κB; NLRP3; NOX4; Thioacetamide.

MeSH terms

  • Animals
  • Antioxidants / pharmacology
  • Fibrosis / chemically induced
  • Fibrosis / drug therapy
  • Fibrosis / metabolism
  • Flavonoids / metabolism
  • Flavonoids / pharmacology*
  • Inflammasomes / metabolism*
  • Inflammation / pathology
  • Liver / metabolism
  • Liver Cirrhosis / chemically induced
  • Liver Cirrhosis / drug therapy*
  • Liver Cirrhosis / metabolism
  • Male
  • NADPH Oxidase 4 / metabolism
  • NF-kappa B / metabolism
  • NLR Family, Pyrin Domain-Containing 3 Protein / metabolism
  • Oxidative Stress / drug effects
  • Rats
  • Rats, Sprague-Dawley
  • Reactive Oxygen Species / metabolism
  • Signal Transduction / drug effects
  • Thioacetamide / adverse effects
  • Thioacetamide / pharmacology

Substances

  • Antioxidants
  • Flavonoids
  • Inflammasomes
  • NF-kappa B
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Nlrp3 protein, rat
  • Reactive Oxygen Species
  • Thioacetamide
  • baicalin
  • NADPH Oxidase 4
  • Nox4 protein, rat