High-Fluence Light-Emitting Diode-Generated Red Light Modulates the Transforming Growth Factor-Beta Pathway in Human Skin Fibroblasts

Dermatol Surg. 2018 Oct;44(10):1317-1322. doi: 10.1097/DSS.0000000000001549.

Abstract

Background: Skin fibrosis is a significant medical problem with limited available treatment modalities. The key cellular characteristics include increased fibroblast proliferation, collagen production, and transforming growth factor-beta (TGF-B)/SMAD pathway signaling. The authors have previously shown that high-fluence light-emitting diode red light (HF-LED-RL) decreases cellular proliferation and collagen production.

Objective: Herein, the authors investigate the ability of HF-LED-RL to modulate the TGF-B/SMAD pathway.

Materials and methods: Normal human dermal fibroblasts were cultured and irradiated with a commercially available hand-held LED array. After irradiation, cell lysates were collected and levels of pSMAD2, TGF-Beta 1, and TGF-Beta I receptor were measured using Western blot.

Results: High-fluence light-emitting diode red light decreased TGF-Beta 1 ligand (TGF-B1) levels after irradiation. 320 J/cm HF-LED-RL resulted in 59% TGF-B1 and 640 J/cm HF-LED-RL resulted in 54% TGF-B1, relative to controls. 640 J/cm HF-LED-RL resulted in 62% pSMAD2 0 hours after irradiation, 65% pSMAD2 2 hours after irradiation, and 95% 4 hours after irradiation, compared with matched controls. High-fluence light-emitting diode red light resulted in no significant difference in transforming growth factor-beta receptor I levels compared with matched controls.

Conclusion: Skin fibrosis is a significant medical problem with limited available treatment modalities. Light-emitting diode-generated red light is a safe, economic, and noninvasive modality that has a body of in vitro evidence supporting the reduction of key cellular characteristics associated with skin fibrosis.

MeSH terms

  • Cell Culture Techniques
  • Fibroblasts / metabolism
  • Fibroblasts / radiation effects*
  • Humans
  • Phototherapy*
  • Skin / cytology
  • Skin / metabolism
  • Skin / radiation effects*
  • Smad2 Protein / metabolism
  • Smad2 Protein / radiation effects
  • Transforming Growth Factor beta / metabolism*
  • Transforming Growth Factor beta / radiation effects

Substances

  • SMAD2 protein, human
  • Smad2 Protein
  • Transforming Growth Factor beta