Mechanisms underlying post-inflammatory hyperpigmentation: lessons from solar lentigo

Ann Dermatol Venereol. 2012 Dec:139 Suppl 4:S148-52. doi: 10.1016/S0151-9638(12)70127-8.


Hyperpigmentation of the skin is a common dermatologic condition in all skin types but most prominent in brown-skinned population. In skin of color any inflammation or injury can be accompanied by alterations in pigmentation (hyper/hypo-pigmentation). Postinflammatory hyperpigmentation (PIH) can be observed in many skin conditions including acne, eczema, and contact dermatitis. In the control of skin pigmentation, parallel to the cross-talk between keratinocytes and melanocytes, increasing evidence has underlined the crucial role exerted by the interactions between mesenchymal and epithelial cells through the release of fibroblast-derived growth factors. Among these factors, the keratinocyte growth factor (KGF), alone or in combination with interleukin-1α, induces melanin deposition in vitro and hyperpigmented lesions in vivo. Furthermore, a moderate increase of KGF and a high induction of its receptor have been shown in solar lentigo lesions, suggesting the involvement of this growth factor in the onset of the hyperpigmented spots. Several studies highlight the possible contribution of the fibroblast-derived melanogenic growth factors to the hyperpigmentated lesions, in the context of the mesenchymal - epithelial interactions modulating melanocyte functions.

Publication types

  • Review

MeSH terms

  • Cells, Cultured / drug effects
  • Cells, Cultured / physiology
  • Coculture Techniques
  • Colforsin / pharmacology
  • Cytokines / physiology
  • Epithelium / physiopathology
  • Fibroblast Growth Factor 7 / physiology
  • Fibroblasts / metabolism
  • Gene Expression Regulation / radiation effects
  • Humans
  • Hyperpigmentation / etiology*
  • Hyperpigmentation / physiopathology
  • Inflammation / complications*
  • Keratinocytes / metabolism
  • Lentigo / etiology
  • Lentigo / physiopathology
  • Melanins / metabolism
  • Melanocytes / metabolism
  • Mesoderm / physiopathology
  • Paracrine Communication
  • Phagocytosis
  • Receptor, Fibroblast Growth Factor, Type 2 / biosynthesis
  • Receptor, Fibroblast Growth Factor, Type 2 / genetics
  • Receptor, Fibroblast Growth Factor, Type 2 / physiology
  • Skin Pigmentation / drug effects
  • Skin Pigmentation / physiology
  • Skin Pigmentation / radiation effects
  • Stem Cell Factor / physiology
  • Sunlight / adverse effects
  • alpha-MSH / pharmacology


  • Cytokines
  • FGF7 protein, human
  • Melanins
  • Stem Cell Factor
  • Fibroblast Growth Factor 7
  • Colforsin
  • alpha-MSH
  • Receptor, Fibroblast Growth Factor, Type 2
  • keratinocyte growth factor receptor