Selenite enhances immune response against Pseudomonas aeruginosa PA14 via SKN-1 in Caenorhabditis elegans

PLoS One. 2014 Aug 22;9(8):e105810. doi: 10.1371/journal.pone.0105810. eCollection 2014.

Abstract

Background: Selenium (Se) is an important nutrient that carries out many biological processes including maintaining optimal immune function. Here, inorganic selenite (Se(IV)) was evaluated for its pathogen resistance and potential-associated factors in Caenorhabditis elegans. The immune effects of Se(IV) were investigated by examining the responses of C. elegans to Pseudomonas aerugonisa PA14 strain.

Principal findings: Se(IV)-treated C. elegans showed increased survival under PA14 infection compared with untreated controls. The significant pathogen resistance of Se(IV) on C. elegans might not be attributed to the effects of Se(IV) on PA14 as Se(IV) showed no effect on bacterial quorum-sensing and virulence factors of PA14. This study showed that Se(IV) enhanced the expression of a gene pivotal for the innate immunity in C. elegans. The study found that the pathogen-resistant phenotypes contributed by Se(IV) was absent from the skn-1 mutant worms. Moreover, Se(IV) influenced the subcellular distribution of SKN-1/Nrf in C. elegans upon PA14 infection. Furthermore, Se(IV) increased mRNA levels of SKN-1 target genes (gst-4 and gcs-1).

Conclusions: This study found evidence of Se(IV) protecting C. elegans against P. aeruginosa PA14 infection by exerting effects on the innate immunity of C. elegans that is likely mediated via regulation of a SKN-1-dependent signaling pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Biofilms
  • Caenorhabditis elegans / drug effects*
  • Caenorhabditis elegans / genetics
  • Caenorhabditis elegans / immunology*
  • Caenorhabditis elegans / microbiology
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / immunology*
  • Caenorhabditis elegans Proteins / metabolism
  • DNA-Binding Proteins / immunology*
  • DNA-Binding Proteins / metabolism
  • Gene Expression Regulation / drug effects
  • Glutamate-Cysteine Ligase / genetics
  • Glutathione Transferase / genetics
  • Pseudomonas aeruginosa / drug effects
  • Pseudomonas aeruginosa / genetics
  • Pseudomonas aeruginosa / pathogenicity*
  • Quorum Sensing
  • Selenious Acid / immunology
  • Selenious Acid / pharmacology*
  • Transcription Factors / immunology*
  • Transcription Factors / metabolism
  • Virulence Factors / genetics

Substances

  • Caenorhabditis elegans Proteins
  • DNA-Binding Proteins
  • Transcription Factors
  • Virulence Factors
  • skn-1 protein, C elegans
  • Glutathione Transferase
  • Glutamate-Cysteine Ligase
  • Selenious Acid

Grants and funding

This work was financially supported by grant (NSC 101-2313-B-002-041-MY3) from the Ministry of Science and Technology of Taiwan (http://www.most.gov.tw/) to VHCL. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.