Changes in collagen I and collagen III metabolism in patients with generalized atopic eczema undergoing medium-dose ultraviolet A1 phototherapy.
Fourteen patients suffering from acute, exacerbated atopic eczema were screened for changes in collagen I and collagen III metabolism in serum (n = 11), urine (n = 11) and skin biopsies (n = 9) before and after medium-dose ultraviolet (UV) A1 phototherapy (15 exposures of 50 J/cm2 over a 3-week period, total dose 750 J/cm2). Mature collagen I and, to a lesser extent, mature collagen III were found to be decreased after the therapy in skin samples from the irradiated patients. As markers of collagen I degradation, the cross-links pyridoline and deoxypyridoline were analysed in urine using high-performance liquid chromatography. Both cross-links were found to be mildly increased after UVA1 phototherapy, without reaching statistical significance. As markers of de novo collagen synthesis we screened for the procollagen I-carboxyterminal peptide (PICP) and procollagen III-aminoterminal peptide (PIIINP) levels in serum and skin. The ratio of PICP to PIIINP in serum dropped significantly after the UVA1 phototherapy, suggesting a different impact of UVA1 on the two collagens. These findings were paralleled by a diminished ratio of PICP to PIIINP in tissue samples. Staining for matrix metalloproteinase 1 (MMP-1) and its specific counterpart, tissue inhibitor of MMP-1 (TIMP-1), showed slight increases for both proteins by therapeutic UVA1; this was also seen in serum for TIMP-1 but not MMP-1. In our study, high-energy UVA1 doses induced changes of the skin collagens in patients with atopic eczema which are measurable by their metabolites in serum and urine.
Mempel
M
M
Klinik und Poliklinik für Dermatologie und Allergologie am Biederstein, Biedersteiner Strasse 29, 80802 Munich, Germany.
Schmidt
T
T
Boeck
K
K
Brockow
K
K
Stachowitz
S
S
Fesq
H
H
Schäfer
T
T
Thomsen
S
S
Schnopp
C
C
Ring
J
J
Probst
R
R
Luppa
P
P
Abeck
D
D
D002851:Chromatography, High Pressure Liquid; D003094:Collagen / Q000096:biosynthesis / Q000378:metabolism*; D003876:Dermatitis, Atopic / Q000378:metabolism / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D011347:Procollagen / Q000378:metabolism; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014467:Ultraviolet Therapy / Q000009:adverse effects*
D011347:Procollagen; D019715:Tissue Inhibitor of Metalloproteinase-1; D003094:Collagen; D020781:Matrix Metalloproteinase 1