Iraqi propolis increases degradation of IL-1β and NLRC4 by autophagy following Pseudomonas aeruginosa infection

Microbes Infect. 2018 Feb;20(2):89-100. doi: 10.1016/j.micinf.2017.10.007. Epub 2017 Nov 8.

Abstract

Autophagy is a cellular process for maintaining cellular homeostasis. This process can be induced by different factors, such as immune stimuli and pathogen-associated molecules. Autophagy has an important role in the control of IL-1β secretion by macrophages and other cell types. In present study, we describe a novel role for Iraqi propolis affecting autophagy in controlling the secretion of IL-1β in bone-marrow macrophages (BMDMs). After infection with Pseudomonas aeruginosa in the presence of propolis, the degradation of IL-1β was induced, and the activity of inflammasome was reduced. Iraqi propolis-induced autophagy in in vitro and in vivo models decreased the levels of IL-1β and caspase-1. Results indicated that IL-1β pathway production is regulated by autophagy via two different novel mechanisms, namely, regulation of the activation of NLRC4 inflammasome and IL-1β targeting for lysosomal degradation.

Keywords: Autophagy; IL-1β; Inflammasome; Iraqi propolis; NLRC4; Pseudomonas aeruginosa.

MeSH terms

  • Animals
  • Apoptosis Regulatory Proteins / genetics
  • Apoptosis Regulatory Proteins / metabolism*
  • Autophagosomes / drug effects
  • Autophagosomes / metabolism
  • Autophagy / drug effects*
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism*
  • Cell Line
  • Female
  • Gene Silencing
  • Humans
  • Inflammasomes / drug effects
  • Inflammasomes / metabolism
  • Interleukin-1beta / blood
  • Interleukin-1beta / metabolism*
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Macrophages / pathology
  • Mice
  • Mice, Inbred C57BL
  • Propolis / administration & dosage
  • Propolis / pharmacology*
  • Pseudomonas Infections / metabolism
  • Pseudomonas Infections / pathology*
  • Pseudomonas aeruginosa / drug effects
  • Pseudomonas aeruginosa / physiology

Substances

  • Apoptosis Regulatory Proteins
  • Calcium-Binding Proteins
  • Inflammasomes
  • Interleukin-1beta
  • Propolis