Particulate matter increases Cutibacterium acnes-induced inflammation in human epidermal keratinocytes via the TLR4/NF-κB pathway

PLoS One. 2022 Aug 10;17(8):e0268595. doi: 10.1371/journal.pone.0268595. eCollection 2022.

Abstract

Recent studies have demonstrated that particulate matter (PM) can induce oxidative stress and inflammatory responses that are related to the development or exacerbation of several inflammatory dermatoses. However, the effect of PM on acne vulgaris has yet to be determined. In this study, we induced acne-like inflammation in HEKn cells with several concentrations of Cutibacterium acnes (C. acnes) and Staphylococcus aureus peptidoglycan (PGN) to investigate whether PM exposure exacerbates acne-like inflammation and elucidate the underlying mechanisms. To confirm whether PM increases the messenger ribonucleic acid (mRNA) and protein levels of proinflammatory cytokines (IL-1α, IL-1β, IL-6, IL-8, and TNF-α) and cyclooxygenase (COX)-2 expression in C. acnes- or PGN-treated HEKn cells, we used quantitative real-time polymerase chain reactions, enzyme-linked immunosorbent assays, and western blot assays. The results demonstrated that C. acnes, PGN, and PM induced the expression of proinflammatory cytokines in a time- and dose-dependent manner at the mRNA and protein levels, respectively. Moreover, PM further increased the expression of proinflammatory cytokines, COX2, TLR4, and the phosphorylation of NF-κB in C. acnes- and PGN-treated HEKn cells. In conclusion, our results suggest that PM may exacerbate acne symptoms by increasing the inflammatory response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acne Vulgaris* / metabolism
  • Cytokines / metabolism
  • Humans
  • Inflammation / metabolism
  • Keratinocytes / metabolism
  • NF-kappa B* / metabolism
  • Particulate Matter / metabolism
  • Particulate Matter / toxicity
  • Peptidoglycan / metabolism
  • Propionibacterium acnes
  • RNA, Messenger / metabolism
  • Toll-Like Receptor 4 / genetics
  • Toll-Like Receptor 4 / metabolism

Substances

  • Cytokines
  • NF-kappa B
  • Particulate Matter
  • Peptidoglycan
  • RNA, Messenger
  • TLR4 protein, human
  • Toll-Like Receptor 4

Associated data

  • figshare/10.6084/m9.figshare.19611795.v1
  • figshare/10.6084/m9.figshare.19611792.v1
  • figshare/10.6084/m9.figshare.19611786.v1
  • figshare/10.6084/m9.figshare.19611783.v1

Grants and funding

This research was supported by ‘2020 AMOREPACIFIC Rising Dermatologist Research Support Program’.