Platelet-activating factor induces proliferation in differentiated keratinocytes

Mol Cell Biochem. 2013 Dec;384(1-2):83-94. doi: 10.1007/s11010-013-1784-6. Epub 2013 Aug 24.

Abstract

Increased levels of platelet-activating factor (PAF; 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) are found in several inflammatory dermatoses, but PAF's exact role in epidermis is uncertain. In order to better understand the physiological consequences of excess PAF production in epidermis, we examined the gene regulatory effects of PAF short-term stimulation in differentiated HaCaT keratinocytes by transcriptional profiling. Even though PAF induces COX2 expression, we found that PAF regulates only few genes associated with inflammation in differentiated keratinocytes. Rather, we show that natural PAF rapidly regulates genes involved in proliferation, (anti)-apoptosis and migration, all sub-processes of re-epithelialization and wound healing. Moreover, profiling of phosphorylated kinases, cellular wound-scratch experiments, resazurin assay and flow cytometry cell cycle phase analysis all support a role for PAF in keratinocyte proliferation and epidermal re-epithelialization. In conclusion, these results suggest that PAF acts as an activator of proliferation and may, therefore, function as a connector between inflammation and proliferation in differentiated keratinocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / genetics
  • Cell Cycle / genetics
  • Cell Differentiation
  • Cell Line
  • Cell Movement / genetics
  • Cell Proliferation*
  • Cyclooxygenase 2 / biosynthesis
  • Cyclooxygenase 2 / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation / genetics*
  • Humans
  • Inflammation / genetics
  • Keratinocytes / metabolism*
  • Mitosis / genetics
  • Platelet Activating Factor / biosynthesis
  • Platelet Activating Factor / metabolism*
  • Re-Epithelialization / genetics
  • Wound Healing / genetics

Substances

  • Platelet Activating Factor
  • Cyclooxygenase 2
  • PTGS2 protein, human