Involvement of reactive oxygen species in the oxidation of tyrosine and dopa to melanin and in skin tanning.

摘要: Abstract The role of reactive oxygen ( 1 O 2 and • ) in skin photosensitization tanning reaction has been examined. Riboflavin (RF), hematoporphyrin (HP), 3-carbethoxypsoralen(3-CP), 8-methoxypsoralen (8-MOP), upon photoexcitation under aerobic conditions, produced singlet ). RF, 3-CP, 8-MOP also superoxide anion Reactive by photosensitized was found to oxidize tyrosine dopa dopachrome subsequently their conversion melanin. HP did not dopachrome, 3-CP RF revealed substantial oxidation tyrosine. Dopa oxidized melanin all photosensitizers tested at a variable rate as follows: > HPD 8-MOP. UVA alone lesser extent UVB which induced the production higher with compared irradiation conditions. These observations appear have relevance -requiring immediate stimulated solar radiation induction photosensitization.