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The expression and activation of protease-activated receptor-2 correlate with skin color

Laura Babiarz-Magee1, Nannan Chen, Miri Seiberg

  • 1Johnson and Johnson Skin Research Center, CPPW, Skillman, NJ 08558, USA.

Pigment Cell Research
|May 14, 2004
PubMed

Insights

Protease-activated receptor-2 (PAR-2) plays a key role in skin pigmentation. Higher PAR-2 expression and activity in darker skin types suggest its involvement in ethnic skin color differences.

Area of Science:

  • Dermatology
  • Cell Biology
  • Biochemistry

Background:

  • Skin color is determined by melanin production and distribution.
  • Protease-activated receptor-2 (PAR-2), found on keratinocytes, influences melanosome uptake and affects skin color.
  • Melanosome distribution patterns are dependent on skin color and keratinocyte origin.

Purpose of the Study:

  • To investigate the role of PAR-2 in skin pigmentation modulation in a skin type-dependent manner.
  • To examine the expression and activity of PAR-2 and its activator, trypsin, in human skin with varying pigmentation levels.

Main Methods:

  • Comparative analysis of PAR-2 and trypsin expression and localization in lightly versus highly pigmented human skin.
  • Assessment of PAR-2-specific protease cleavage ability in different skin types.
  • In vitro phagocytosis assays using microspheres in keratinocytes derived from various skin pigmentation backgrounds.

Main Results:

  • PAR-2 and trypsin expression levels and localization differed significantly between highly pigmented and lightly pigmented skin.
  • Highly pigmented skin exhibited enhanced PAR-2-specific protease cleavage ability.
  • Keratinocytes from highly pigmented skin showed more efficient microsphere phagocytosis, particularly when induced by PAR-2.

Conclusions:

  • PAR-2 expression and activity correlate with skin color.
  • The findings suggest a significant involvement of PAR-2 in the determination of ethnic skin color phenotypes.

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