The Protective Role of Garlic on Allergen-Induced Airway Inflammation in Mice

Am J Chin Med. 2019;47(5):1099-1112. doi: 10.1142/S0192415X19500563. Epub 2019 Jul 31.


Asthma is the most prevalent chronic respiratory disease worldwide. Garlic extracts have long been used as a food source and in traditional medicine. Crude extracts of garlic are used as an anti-inflammatory agent and have been reported to exhibit antiasthmatic properties. However, molecular mechanisms of garlic extracts in the context of antiasthmatic airway inflammation are still unclear. In this study, the antiasthmatic effect of garlic extracts on Th1, Th2, and Th3 cytokine profiles and immunoregulatory mechanism were explored using an animal model of allergic asthma. Garlic extracts significantly reduced total inflammatory cell counts and eosinophil infiltration and decreased the production of Dermatophagoides pteronyssinus IgE in serum and Th1/Th2/Th3 cytokine in bronchoalveolar fluid. Enzyme-linked immunosorbent assay analysis demonstrated that garlic extracts downregulated the levels of cytokines and chemokines, namely Th2-related IL-4, IL-5, and IL-13; but they simultaneously upregulated Th1-related IFN-γ, IL-12, and Th3-related IL-10 and TGF-β expression in BALF. The mechanism may be ascribed to the modulation of Th1-, Th2-, and Th3-related cytokine imbalance.

Keywords: Airway Inflammation; Bronchoalveolar Fluid; Garlic; Th1/Th2/Th3 Cytokines.

MeSH terms

  • Allergens / adverse effects
  • Animals
  • Anti-Inflammatory Agents / administration & dosage
  • Asthma / chemically induced
  • Asthma / genetics
  • Asthma / immunology
  • Asthma / prevention & control*
  • Female
  • Garlic / chemistry*
  • Humans
  • Immunoglobulin E / immunology
  • Interleukin-12 / genetics
  • Interleukin-12 / immunology
  • Interleukin-5 / genetics
  • Interleukin-5 / immunology
  • Mice
  • Mice, Inbred BALB C
  • Plant Extracts / administration & dosage*
  • Protective Agents / administration & dosage*
  • Th1 Cells / drug effects
  • Th1 Cells / immunology
  • Th2 Cells / drug effects
  • Th2 Cells / immunology


  • Allergens
  • Anti-Inflammatory Agents
  • Interleukin-5
  • Plant Extracts
  • Protective Agents
  • Interleukin-12
  • Immunoglobulin E