Zinc suppressed the airway inflammation in asthmatic rats: effects of zinc on generation of eotaxin, MCP-1, IL-8, IL-4, and IFN-γ

Biol Trace Elem Res. 2012 Dec;150(1-3):314-21. doi: 10.1007/s12011-012-9493-7. Epub 2012 Aug 30.

Abstract

Airway epithelium is rich in labile zinc (Zn), which may have an important protective role in the airway epithelium. The aim of this study is to investigate the effects of Zn on the airway inflammation and the generation of eotaxin, monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), interleukin-4 (IL-4), and interferon-γ (IFN-γ) in rat models of ovalbumin (OVA)-induced allergic airway inflammation. For this purpose, animal model of asthma was established by OVA challenge and zinc-deficient and zinc-supplemented diets were given. Thirty-two Sprague-Dawley rats were divided into four groups: zinc-deficient diet with OVA treatment group, zinc-supplemented diet with OVA treatment group, zinc-normal diet with OVA treatment group, and zinc-normal diet with saline treatment group. Twenty-four hours after asthma was induced, lung histomorphological changes, cells in bronchoalveolar lavage fluid (BALF), contents of eotaxin, MCP-1, and IL-8 in BALF, and the expression of IFN-γ and IL-4 mRNAs were observed. Compared with the group of zinc-normal diet with OVA challenge rats, the group of zinc-deficient rats had higher numbers of eosinophils, neutrophils, and monocytes in BALF, as well as higher contents of eotaxin and MCP-1 in BALF and lower expression of lung IFN-γ mRNA. Conversely, Zn supplementation would decrease the numbers of eosinophils, neutrophils, and monocytes in BALF; suppress eotaxin and MCP-1 protein secretion; and increase lung IFN-γ mRNA expression. No significant difference was observed in IL-8 and IL-4 among OVA-challenged rats with different zinc diets. These studies suggested that Zn may be an important anti-inflammatory mediator of airway inflammation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Asthmatic Agents / therapeutic use*
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use*
  • Asthma / diet therapy*
  • Asthma / etiology
  • Asthma / immunology
  • Asthma / metabolism
  • Bronchoalveolar Lavage Fluid / chemistry
  • Bronchoalveolar Lavage Fluid / cytology
  • Bronchoalveolar Lavage Fluid / immunology
  • Cell Count
  • Cytokines / antagonists & inhibitors
  • Cytokines / genetics
  • Cytokines / metabolism
  • Dietary Supplements*
  • Eosinophils / immunology
  • Eosinophils / metabolism
  • Gene Expression Regulation
  • Lung / cytology
  • Lung / immunology*
  • Lung / metabolism
  • Male
  • Monocytes / immunology
  • Monocytes / metabolism
  • Neutrophil Infiltration
  • Neutrophils / immunology
  • Neutrophils / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Respiratory Mucosa / cytology
  • Respiratory Mucosa / immunology*
  • Respiratory Mucosa / metabolism
  • Spectrophotometry, Atomic
  • Zinc / blood
  • Zinc / deficiency
  • Zinc / therapeutic use*

Substances

  • Anti-Asthmatic Agents
  • Anti-Inflammatory Agents, Non-Steroidal
  • Cytokines
  • Zinc