Brown Pine Leaf Extract and Its Active Component Trans-Communic Acid Inhibit UVB-Induced MMP-1 Expression by Targeting PI3K

PLoS One. 2015 Jun 11;10(6):e0128365. doi: 10.1371/journal.pone.0128365. eCollection 2015.


Japanese red pine (Pinus densiflora) is widely present in China, Japan, and Korea. Its green pine leaves have traditionally been used as a food as well as a coloring agent. After being shed, pine leaves change their color from green to brown within two years, and although the brown pine leaves are abundantly available, their value has not been closely assessed. In this study, we investigated the potential anti-photoaging properties of brown pine leaves for skin. Brown pine leaf extract (BPLE) inhibited UVB-induced matrix metalloproteinase-1 (MMP-1) expression to a greater extent than pine leaf extract (PLE) in human keratinocytes and a human skin equivalent model. HPLC analysis revealed that the quantity of trans-communic acid (TCA) and dehydroabietic acid (DAA) significantly increases when the pine leaf color changes from green to brown. BPLE and TCA elicited reductions in UVB-induced MMP-1 mRNA expression and activator protein-1 (AP-1) transactivation by reducing DNA binding activity of phospho-c-Jun, c-fos and Fra-1. BPLE and TCA also inhibited UVB-induced Akt phosphorylation, but not mitogen activated protein kinase (MAPK), known regulators of AP-1 transactivation. We additionally found that BPLE and TCA inhibited phosphoinositide 3-kinase (PI3K), the upstream kinase of Akt, in vitro. In summary, both BPLE and its active component TCA exhibit protective effects against UVB-induced skin aging. Taken together, these findings underline the potential for BPLE and TCA to be utilized as anti-wrinkling agents and cosmetic ingredients, as they suppress UVB-induced MMP-1 expression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abietanes / chemistry
  • Abietanes / isolation & purification
  • Abietanes / pharmacology
  • Cell Culture Techniques
  • Cell Line
  • Cell Survival / drug effects
  • Cell Survival / radiation effects
  • Diterpenes / chemistry
  • Diterpenes / isolation & purification
  • Diterpenes / pharmacology*
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • Fibroblasts / radiation effects
  • Humans
  • Isomerism
  • Matrix Metalloproteinase 1 / genetics*
  • Models, Biological
  • Phosphatidylinositol 3-Kinases / chemistry
  • Phosphatidylinositol 3-Kinases / metabolism*
  • Phosphorylation / drug effects
  • Phosphorylation / radiation effects
  • Pinus / chemistry*
  • Pinus / metabolism
  • Plant Extracts / chemistry
  • Plant Extracts / pharmacology*
  • Plant Leaves / chemistry
  • Plant Leaves / metabolism
  • Proto-Oncogene Proteins c-akt / metabolism
  • Real-Time Polymerase Chain Reaction
  • Transcription Factor AP-1 / genetics
  • Transcription Factor AP-1 / metabolism
  • Transcriptional Activation / drug effects*
  • Ultraviolet Rays


  • Abietanes
  • Diterpenes
  • Plant Extracts
  • Transcription Factor AP-1
  • communic acid
  • dehydroabietic acid
  • Proto-Oncogene Proteins c-akt
  • Matrix Metalloproteinase 1

Grants and funding

This work was supported by the R & D program (N0000697) of MOTIE/KIAT (Establishment of Infra Structure for Anti-aging Industry Support) and the Leap Research Program Grant (2010-0029233) through the National Research Foundation funded by the Ministry of Science, ICT and Future Planning of Republic of Korea.