Relationship between type 2 cytokine and inflammasome responses in obesity-associated asthma

J Allergy Clin Immunol. 2022 Apr;149(4):1270-1280. doi: 10.1016/j.jaci.2021.10.003. Epub 2021 Oct 19.

Abstract

Background: Obesity is a risk factor for asthma, and obese asthmatic individuals are more likely to have severe, steroid-insensitive disease. How obesity affects the pathogenesis and severity of asthma is poorly understood. Roles for increased inflammasome-mediated neutrophilic responses, type 2 immunity, and eosinophilic inflammation have been described.

Objective: We investigated how obesity affects the pathogenesis and severity of asthma and identified effective therapies for obesity-associated disease.

Methods: We assessed associations between body mass index and inflammasome responses with type 2 (T2) immune responses in the sputum of 25 subjects with asthma. Functional roles for NLR family, pyrin domain-containing (NLRP) 3 inflammasome and T2 cytokine responses in driving key features of disease were examined in experimental high-fat diet-induced obesity and asthma.

Results: Body mass index and inflammasome responses positively correlated with increased IL-5 and IL-13 expression as well as C-C chemokine receptor type 3 expression in the sputum of subjects with asthma. High-fat diet-induced obesity resulted in steroid-insensitive airway hyperresponsiveness in both the presence and absence of experimental asthma. High-fat diet-induced obesity was also associated with increased NLRP3 inflammasome responses and eosinophilic inflammation in airway tissue, but not lumen, in experimental asthma. Inhibition of NLRP3 inflammasome responses reduced steroid-insensitive airway hyperresponsiveness but had no effect on IL-5 or IL-13 responses in experimental asthma. Depletion of IL-5 and IL-13 reduced obesity-induced NLRP3 inflammasome responses and steroid-insensitive airway hyperresponsiveness in experimental asthma.

Conclusion: We found a relationship between T2 cytokine and NLRP3 inflammasome responses in obesity-associated asthma, highlighting the potential utility of T2 cytokine-targeted biologics and inflammasome inhibitors.

Keywords: Asthma; IL-13; IL-5; NLRP3 inflammasomes; obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Asthma*
  • Cytokines
  • Humans
  • Inflammasomes* / metabolism
  • Inflammation / metabolism
  • Interleukin-13
  • Interleukin-1beta
  • Interleukin-5
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • Obesity / complications

Substances

  • Cytokines
  • Inflammasomes
  • Interleukin-13
  • Interleukin-1beta
  • Interleukin-5
  • NLR Family, Pyrin Domain-Containing 3 Protein