Topical Application of Cinnamaldehyde Promotes Faster Healing of Skin Wounds Infected with Pseudomonas aeruginosa

Molecules. 2019 Apr 25;24(8):1627. doi: 10.3390/molecules24081627.

Abstract

Wound healing can be delayed following colonization and infection with the common bacterium Pseudomonas aeruginosa. While multiple therapies are used for their treatment, these are ineffective, expensive, and labour-intensive. Thus, there is an enormous unmet need for the treatment of infected wounds. Cinnamaldehyde, the major component of cinnamon oil, is well known for its antimicrobial properties. Herein, we investigated the effects of sub-inhibitory concentrations of cinnamaldehyde in the virulence of P. aeruginosa. We also assessed its healing potential in P. aeruginosa-infected mouse skin wounds and the mechanisms involved in this response. Sub-inhibitory concentrations of cinnamaldehyde reduced P. aeruginosa metabolic rate and its ability to form biofilm and to cause haemolysis. Daily topical application of cinnamaldehyde on P. aeruginosa-infected skin wounds reduced tissue bacterial load and promoted faster healing. Lower interleukin-17 (IL-17), vascular endothelial growth factor (VEGF) and nitric oxide levels were detected in cinnamaldehyde-treated wound samples. Blockage of transient receptor potential ankyrin 1, the pharmacological target of cinnamaldehyde, abrogated its healing activity and partially reversed the inhibitory actions of this compound on VEGF and IL-17 generation. We suggest that topical application of sub-inhibitory concentrations of cinnamaldehyde may represent an interesting approach to improve the healing of P. aeruginosa-infected skin wounds.

Keywords: Pseudomonas aeruginosa; cinnamaldehyde; skin wound; wound healing.

MeSH terms

  • Acrolein / analogs & derivatives*
  • Acrolein / therapeutic use
  • Animals
  • Anti-Infective Agents / therapeutic use
  • Biofilms / drug effects
  • Disease Models, Animal
  • Female
  • Interleukin-17 / metabolism
  • Mice
  • Pseudomonas Infections / drug therapy
  • Pseudomonas aeruginosa / drug effects*
  • Pseudomonas aeruginosa / pathogenicity*
  • Skin / microbiology*
  • TRPA1 Cation Channel / metabolism
  • Vascular Endothelial Growth Factor A / metabolism
  • Wound Healing / drug effects*

Substances

  • Anti-Infective Agents
  • Interleukin-17
  • TRPA1 Cation Channel
  • Vascular Endothelial Growth Factor A
  • Acrolein
  • cinnamaldehyde