title: Prolonged increase of cis-urocanic acid levels in human skin and urine after single total-body ultraviolet exposures.
abstract: Cis-urocanic acid (cis-UCA), a mediator of immunosuppression, is formed from trans-UCA upon UV-exposure of the skin. This study describes a liquid chromatographic method for the simultaneous quantification of cis- and trans-UCA in skin, urine and plasma of nonirradiated volunteers. It also describes cis- and trans-UCA kinetics in UV-irradiated volunteers. New procedures to remove interfering substances from urine and plasma are reported. Normal levels of cis-UCA in skin, urine and plasma of nonirradiated volunteers were 0.5 nmol/cm2, 0.03 mumol/mmol creatinine (median 0.00) and undetectable and those of trans-UCA were 17.1 nmol/cm2, 1.36 mumol/ mmol creatinine and 0.5 microM, respectively. Upon single total body UVB (290-320 nm) exposures of 250 J/m2, epidermal cis-UCA levels immediately reached a maximum and returned to basic levels 3 weeks later. The cis-UCA levels in urine reached a maximum in 5-12 h postirradiation and reached baseline values in 8-12 days. Additionally, a single total body UVA (320-400 nm) irradiation of 200 kJ/m2 yielded a similar pattern. The kinetics of cis-UCA in plasma could not be followed due to low concentrations; however, that of skin and urine was informative in relation to solar exposures and phototherapy.
authors.affiliation: Department of Dermatology, University of Amsterdam, The Netherlands, A.Kammeyer@AMC.UVA.NL
authors.forename: A
authors.initials: A
authors.lastname: Kammeyer
authors.forename: S
authors.initials: S
authors.lastname: Pavel
authors.forename: S S
authors.initials: SS
authors.lastname: Asghar
authors.forename: J D
authors.initials: JD
authors.lastname: Bos
authors.forename: M B
authors.initials: MB
authors.lastname: Teunissen
mesh_terms: D000293:Adolescent; D000328:Adult; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012867:Skin / Q000378:metabolism / Q000528:radiation effects; D014466:Ultraviolet Rays; D014560:Urocanic Acid / Q000097:blood / Q000378:metabolism* / Q000652:urine
chemical_list: D014560:Urocanic Acid