Influence of Birch Bark Triterpenes on Keratinocytes and Fibroblasts from Diabetic and Nondiabetic Donors

J Nat Prod. 2016 Apr 22;79(4):1112-23. doi: 10.1021/acs.jnatprod.6b00027. Epub 2016 Mar 22.


Impaired wound healing is one of the main risk factors associated with diabetes mellitus. Few options are available to treat diabetic wounds, and therefore efficient remedies are urgently needed. An interesting option might be an extract of birch bark (TE) that has been clinically proven to accelerate acute wound healing. We investigated the effects of TE and its main components betulin and lupeol in cultured normal keratinocytes and dermal fibroblasts from diabetic and nondiabetic donors. These in vitro models can provide insights into possible beneficial effects in wound healing. TE and betulin treatment led to increased mRNA levels of chemokines, pro-inflammatory cytokines, and mediators important in wound healing, e.g., IL-6, TNFα, IL-8, and RANTES. We observed a pronounced upregulation of MIF, IL-8, and RANTES on the protein level. Furthermore, a shape change of the actin cytoskeleton was seen in keratinocytes and fibroblasts, and the Rho-GTPases and p38-MAPK were found to be activated in keratinocytes. On the basis of our results, TE is worthy of further study as a potential option to influence wound-healing processes under diabetic conditions. These first insights need to be confirmed by clinical studies with diabetic patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Betula / chemistry*
  • Cytokines / metabolism
  • Diabetes Mellitus / drug therapy*
  • Female
  • Fibroblasts / metabolism
  • Humans
  • Interleukin-6 / metabolism
  • Interleukin-8 / metabolism
  • Keratinocytes / drug effects*
  • Pentacyclic Triterpenes / chemistry
  • Pentacyclic Triterpenes / isolation & purification
  • Pentacyclic Triterpenes / pharmacology*
  • Plant Bark / chemistry
  • Triterpenes / chemistry
  • Triterpenes / isolation & purification*
  • Triterpenes / pharmacology*
  • Wound Healing / drug effects
  • p38 Mitogen-Activated Protein Kinases / metabolism
  • rho GTP-Binding Proteins / metabolism


  • Cytokines
  • Interleukin-6
  • Interleukin-8
  • Pentacyclic Triterpenes
  • Triterpenes
  • betulin
  • p38 Mitogen-Activated Protein Kinases
  • rho GTP-Binding Proteins
  • lupeol