Antiphotoaging effects of light-emitting diode irradiation on narrow-band ultraviolet B-exposed cultured human skin cells

Dermatol Surg. 2012 Oct;38(10):1695-703. doi: 10.1111/j.1524-4725.2012.02501.x. Epub 2012 Jul 16.


Background: Antiaging effects of light-emitting diodes (LEDs) have been clinically demonstrated using one or two wavelengths. The mechanism is unclear.

Objective: To examine direct and indirect photobiomodulation effects of LEDs on narrow-band ultraviolet B (NB-UVB)-induced photoaging using seven different wavelengths alone or in combination.

Materials and methods: Four LED wavelengths were chosen based on type I collagen and metalloproteinase (MMP)-1 expression. NB-UVB-irradiated fibroblasts or keratinocytes were irradiated using these four wavelengths. The expression of collagen and MMP-1 in fibroblasts with or without conditioned medium from LED-irradiated keratinocytes and the expression of proinflammatory cytokines in the LED-irradiated keratinocytes were examined.

Results: Irradiation with four wavelengths (630, 660, 830, and 850 nm) significantly increased the number of viable fibroblasts. These four wavelengths also increased type I collagen expression, particularly four combinations (630/830, 660/850, 630/850, and 660/830 nm). The fibroblasts cultured with the keratinocyte conditioned medium, particularly with a combination of 630/850 or 660/830 nm, increased collagen levels. Low tumor necrosis factor alpha (TNF-α) and high transforming growth factor beta 1 (TGF-β1) expression was detected in the LED-irradiated keratinocytes.

Conclusion: The combination of 630/850- or 660/830-nm irradiation led to better direct and indirect antiphotoaging outcomes than single LED wavelengths in NB-UVB-irradiated cultured normal human skin cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Cell Proliferation / radiation effects
  • Collagen Type I / biosynthesis
  • Fibroblasts / metabolism*
  • Fibroblasts / radiation effects
  • Humans
  • Keratinocytes / metabolism*
  • Keratinocytes / radiation effects
  • Matrix Metalloproteinase 1 / metabolism
  • Phototherapy* / methods
  • Skin Aging*
  • Transforming Growth Factor beta1 / metabolism
  • Tumor Necrosis Factor-alpha / metabolism
  • Ultraviolet Rays / adverse effects*


  • Collagen Type I
  • Transforming Growth Factor beta1
  • Tumor Necrosis Factor-alpha
  • Matrix Metalloproteinase 1