Chart 3.
Effects of factors secreted by keratinocytes after exposure to UVR, with paracrine action
| Melanocyte proliferation | Dendricity | Melanin synthesis | Melanosome transfer | Survival / Cytoprotection | |
| ACTH | ↑ | ↑ | ↑ | ||
| α-MSH | ↑ | ↑ | ↑ | ↑ | |
| bFGF | ↑↑ | ||||
| ET-1 | ↑ | ↑ | ↑ | ||
| GM-CSF | ↑ | ↑ | |||
| NO | ↑ | ||||
| NGF | ↑ | ↑ | |||
| PGE2/PGF2α | ↑ | ↑ | ↑ | ||
| IL-1 | ↓ | ↑ | ↓ | ||
| TNF-α | ↓ | ||||
| BMP-4 | ↓ |
Adapted from Wolff K et al., 2007.12
ACTH (adrenocorticotropic hormone), α-MSH (melanocyte-stimulating hormone), bFGF (basic fibroblast growth factor), BMP-4 (bone morphogenic protein-4), ET-1 (endotheIin-1), GM-CSF (granulocyte-macrophage colony-stimuIating factor), IL-1 (interleukin 1), NO (nitric oxide), NGF (nerve growth factor); PGE2/PGF2α (prostaglandin E2 and F2α), TNF-α (tumor necrosis factor-α).