Urocanic acid isomers are good hydroxyl radical scavengers: a comparative study with structural analogues and with uric acid.
UV-exposure of the epidermis leads to the isomerisation of trans-UCA into cis-UCA as well as to the generation of hydroxyl radicals. This study shows by means of the deoxyribose degradation test that UCA isomers are more powerful hydroxyl radical scavengers than the other 4-(5-)substituted imidazole derivatives, such as histidine, though less powerful than uric acid. UCA, present in relatively high concentrations in the epidermis, may well be a major natural hydroxyl radical scavenger.
Kammeyer
A
A
Department of Dermatology, Academic Medical Centre, P.O. Box 22660, 1100 DD, Amsterdam, The Netherlands. a.kammeyer@amc.uva.nl
Eggelte
T A
TA
Bos
J D
JD
Teunissen
M B
MB
D003855:Deoxyribose; D016166:Free Radical Scavengers / Q000737:chemistry*; D006801:Humans; D017665:Hydroxyl Radical / Q000737:chemistry*; D007536:Isomerism; D015394:Molecular Structure; D012867:Skin / Q000737:chemistry / Q000528:radiation effects*; D014527:Uric Acid / Q000737:chemistry*; D014560:Urocanic Acid / Q000031:analogs & derivatives / Q000737:chemistry*
D016166:Free Radical Scavengers; D014527:Uric Acid; D017665:Hydroxyl Radical; D003855:Deoxyribose; D014560:Urocanic Acid