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UV-induced DNA damage initiates release of MMP-1 in human skin

Kelly K Dong1, Niusha Damaghi, Stephanie D Picart

  • 1AGI Dermatics, Freeport, New York, USA.

Experimental Dermatology
|May 8, 2008
PubMed

Insights

Sunlight exposure induces matrix metalloproteinase-1 (MMP-1) in skin, leading to collagen destruction and photoaging. DNA repair enzymes applied to skin cells reduced MMP-1, suggesting DNA damage in keratinocytes triggers this process.

Area of Science:

  • Dermatology
  • Molecular Biology
  • Biochemistry

Background:

  • Photoaging, characterized by collagen degradation, is primarily driven by matrix metalloproteinase-1 (MMP-1) induction from sunlight exposure.
  • Ultraviolet-B (UVB) radiation is a key factor in initiating the molecular cascade leading to photoaging and skin damage.

Purpose of the Study:

  • To investigate the molecular triggers of MMP-1 induction in human skin following UVB irradiation.
  • To assess the efficacy of DNA repair enzymes in mitigating UVB-induced MMP-1 expression and subsequent collagen degradation.

Main Methods:

  • Human skin samples were subjected to UVB irradiation and treated with liposome-encapsulated DNA repair enzymes.
  • Epidermal keratinocytes were UVB-irradiated, and their conditioned media were transferred to dermal fibroblasts to assess intercellular signaling.
  • MMP-1 mRNA and protein levels were quantified using molecular and biochemical assays.

Main Results:

  • Photolyase-mediated DNA repair of epidermal UV damage correlated with reduced MMP-1 mRNA and protein in both epidermal and dermal compartments.
  • Media transfer from UVB-irradiated keratinocytes to fibroblasts significantly increased MMP-1 expression, indicating soluble mediator involvement.
  • Pre-treatment of keratinocytes with DNA repair enzymes (T4 endonuclease V or UV endonuclease) prior to media transfer reduced MMP-1 induction.

Conclusions:

  • UVB-induced DNA damage in epidermal keratinocytes initiates signaling pathways that stimulate fibroblasts to release MMP-1, contributing to collagen destruction in photoaging.
  • Enhancing DNA repair mechanisms in skin cells can effectively reduce MMP-1 expression and potentially mitigate the effects of photoaging.

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