Punica granatum L. Leaf Extract Attenuates Lung Inflammation in Mice with Acute Lung Injury

J Immunol Res. 2018 Feb 20:2018:6879183. doi: 10.1155/2018/6879183. eCollection 2018.

Abstract

The hydroalcoholic extract of Punica granatum (pomegranate) leaves was previously demonstrated to be anti-inflammatory in a rat model of lipopolysaccharide- (LPS-) induced acute peritonitis. Here, we investigated the anti-inflammatory effects of the ethyl acetate fraction obtained from the pomegranate leaf hydroalcoholic extract (EAFPg) on the LPS-induced acute lung injury (ALI) mouse model. Male Swiss mice received either EAFPg at different doses or dexamethasone (per os) prior to LPS intranasal instillation. Vehicle-treated mice were used as controls. Animals were culled at 4 h after LPS challenge, and the bronchoalveolar lavage fluid (BALF) and lung samples were collected for analysis. EAFPg and kaempferol effects on NO and cytokine production by LPS-stimulated RAW 264.7 macrophages were also investigated. Pretreatment with EAFPg (100-300 mg/kg) markedly reduced cell accumulation (specially neutrophils) and collagen deposition in the lungs of ALI mice. The same animals presented with reduced lung and BALF TNF-α and IL-1β expression in comparison with vehicle controls (p < 0.05). Additionally, incubation with either EAFPg or kaempferol (100 μg/ml) reduced NO production and cytokine gene expression in cultured LPS-treated RAW 264.7 macrophages. Overall, these results demonstrate that the prophylactic treatment with EAFPg attenuates acute lung inflammation. We suggest this fraction may be useful in treating ALI.

MeSH terms

  • Acetates / chemistry
  • Acute Lung Injury / immunology
  • Acute Lung Injury / therapy*
  • Animals
  • Disease Models, Animal
  • Humans
  • Interleukin-1beta / metabolism
  • Lipopolysaccharides / immunology
  • Lythraceae / immunology
  • Macrophages / drug effects*
  • Macrophages / immunology
  • Male
  • Mice
  • Nitric Oxide / metabolism
  • Plant Extracts / chemistry
  • Plant Extracts / therapeutic use*
  • Plant Leaves
  • Pneumonia / immunology
  • Pneumonia / therapy*
  • RAW 264.7 Cells
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Acetates
  • Interleukin-1beta
  • Lipopolysaccharides
  • Plant Extracts
  • Tumor Necrosis Factor-alpha
  • Nitric Oxide
  • ethyl acetate