5-S-cysteinyl-dopa (cysdopa) and 5-S-cysteinyl-dopamine (cysdopamine) are oxidized in vitro by soybean lipoxygenase (LOX) in the presence of hydrogen peroxide giving rise to the corresponding pheomelanins. The reaction is activated by caffeic acid and other catechols, suggesting a cofactor role for these compounds. The activating effect is proportional to the concentration of the cofactor, with a saturation profile. The activation extent of the various cofactors is directly related to LOX affinity for the same compounds. The possible implications of the peroxidative action of LOX in Parkinson's disease and in aging are discussed.
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Research progress on pathogenesis of skin pigmentation in chronic liver disease.
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Department and Institute of Infectious Disease, Tongji Hospital, Tongji Medical College and State Key Laboratory for Diagnosis and Treatment of Severe Zoonotic Infectious Disease, Huazhong University of Science and Technology, Wuhan, China.
Chronic liver disease (CLD) is a significant global health concern that leads to increased morbidity and mortality, and is associated with skin pigmentation changes. Excessive facial pigmentation is a common characteristic of patients with CLD, although the exact mechanism underlying this phenomenon remains unclear. Melanin, which consists of eumelanin and pheomelanin, is synthesized in melanocytes.
View Article and Find Full Text PDFPlumage polymorphism in the black sparrowhawk (Accipiter melanoleucus) is strongly associated with expression level of agouti signalling protein.
J Hered
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Department of Molecular and Cell Biology, University of Cape Town, South Africa.
Article Synopsis
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Division of Photobiology and Photomedicine, Department of Dermatology, Henry Ford Health, 3031 W Grand Blvd, Suite 800 Dermatology, Detroit, MI, 48202, USA.
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Estación Científica La Malinche, Centro Tlaxcala de Biología de la Conducta (CTBC), Universidad Autónoma de Tlaxcala, Tlaxcala, México.
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Biomimetic conjugation inspired from pheomelanin via thiol-quinone addition for enzymatic functionalization of fibroin.
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Department of Pharmaceutical and Biological Engineering, School of Chemical Engineering, Sichuan University, Chengdu 610065, China. Electronic address:
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