US EPA

8237320 

Journal Article 

The role of calcitonin gene-related peptide in cutaneous immunosuppression induced by repeated subinflammatory ultraviolet irradiation exposure 

Legat, FJ; Jaiani, LT; Wolf, P; Wang, M; Lang, R; Abraham, T; Solomon, AR; Armstrong, CA; Glass, JD; Ansel, JC 

2004 

1 

Experimental Dermatology
ISSN: 0906-6705
EISSN: 1600-0625 

WILEY 

HOBOKEN 

13 

4 

242-250 

English 

15086340 

10.1111/j.0906-6705.2004.00185.x 

WOS:000220839300005 

Ultraviolet (UV) light is an effective treatment for skin disorders like psoriasis in which the cutaneous neurosensory system may have a pathogenic role. In this study, we examined the possibility that UV modulation of the cutaneous neurosensory system and calcitonin gene-related peptide (CGRP) may contribute to local immunosuppression mediated by repeated subinflammatory UV irradiation. Our results indicated that exposure of hairless mice to subinflammatory UV three times weekly for 4 weeks significantly increased the number of epidermal nerve fibers (ENFs) immunoreactive for CGRP without altering the total number of ENFs. The skin content of CGRP as measured by enzyme-linked immunosorbent assay was also significantly increased after exposure to this dose of UV. These effects were most apparent 1 day after the last UV exposure and declined 1 week after UV. The role of CGRP in UV-induced immunosuppression of contact hypersensitivity was then examined. Our results indicated that UV suppression of epicutaneous 2,4-dinitro-1-fluorobenzene (DNFB) sensitization could be significantly inhibited by a systemically administered CGRP receptor antagonist. A broad-spectrum sunscreen applied before UV exposure inhibited increased cutaneous CGRP and blocked immunosuppression. These findings support a role for CGRP in the local immunosuppression caused by chronic, repeated subinflammatory UV exposure. © Blackwell Munksgaard, 2004. 

Broad-spectrum sunscreen; CGRP8-37; Contact hypersensitivity reaction; Epidermal nerve fibers; Neuropeptides