Naringin attenuates acute lung injury in LPS-treated mice by inhibiting NF-κB pathway

Int Immunopharmacol. 2011 Oct;11(10):1606-12. doi: 10.1016/j.intimp.2011.05.022. Epub 2011 Jun 1.

Abstract

Naringin has been reported as an effective anti-inflammatory compound. We previously showed that naringin had antitussive effect on experimentally induced cough in guinea pigs. However, the effects and mechanism of naringin on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice are not fully understood. In this study, our aim was to evaluate the anti-inflammatory activities of naringin on LPS-induced ALI in mice and clarify its underlying mechanisms of action. We found that in vivo pretreatment with naringin markedly decreased the lung wet weight to dry weight ratio, and led to significant attenuation of LPS-induced evident lung histopathological changes. Meanwhile, naringin significantly reduced bronchoalveolar lavage fluid (BALF) total cell and neutrophil (PMN) counts after LPS challenge. Furthermore, naringin inhibited myeloperoxidase (MPO: a marker enzyme of neutrophil granule) and inducible nitric oxide synthase (iNOS) activities in lung tissue and alleviated LPS-induced tumor neurosis factor-α (TNF-α) secretion in BALF in a dose-dependent manner. Additionally, Western blotting showed that naringin efficiently blunt NF-κB activation by inhibiting the degradation of IĸB-α and the translocation of p65. Taken together, these results suggest that naringin shows anti-inflammatory effects through inhibiting lung edema, MPO and iNOS activities, TNF-α secretion and pulmonary neutrophil infiltration by blockade of NF-κB in LPS-induced ALI.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Lung Injury / chemically induced
  • Acute Lung Injury / drug therapy*
  • Acute Lung Injury / physiopathology
  • Animals
  • Anti-Inflammatory Agents / administration & dosage*
  • Anti-Inflammatory Agents / adverse effects
  • Bronchoalveolar Lavage Fluid / chemistry
  • Bronchoalveolar Lavage Fluid / cytology*
  • Bronchoalveolar Lavage Fluid / immunology
  • Cell Count
  • Enzyme Activation / drug effects
  • Flavanones / administration & dosage*
  • Flavanones / adverse effects
  • Lipopolysaccharides / administration & dosage
  • Lung / drug effects
  • Lung / enzymology
  • Lung / pathology
  • Mice
  • Mice, Inbred Strains
  • NF-kappa B / immunology
  • NF-kappa B / metabolism*
  • Neutrophils / pathology
  • Nitric Oxide Synthase Type II / metabolism
  • Peroxidase / metabolism
  • Signal Transduction / drug effects
  • Signal Transduction / immunology
  • Tumor Necrosis Factor-alpha / analysis

Substances

  • Anti-Inflammatory Agents
  • Flavanones
  • Lipopolysaccharides
  • NF-kappa B
  • Tumor Necrosis Factor-alpha
  • Peroxidase
  • Nitric Oxide Synthase Type II
  • naringin