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An investigation on the possible role of melatonin in melanogenesis

โœ Scribed by Andrea Rizzi; Stefano Comai; Antonella Bertazzo; Carlo V. L. Costa; Graziella Allegri; Pietro Traldi


Publisher
John Wiley and Sons
Year
2006
Tongue
English
Weight
445 KB
Volume
41
Category
Article
ISSN
1076-5174

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โœฆ Synopsis


Abstract

The possible role of melatonin in melanogenesis was investigated by performing reactions of melatonin with peroxidase + H~2~O~2~ or H~2~O~2~ only, in the presence or absence of UV irradiation. Samples of the reaction mixtures were drawn at different times (from 15 to 480 min), the enzyme (when present) was removed by ultrafiltration and the samples so obtained were analyzed by MALDI/MS.

The results show that melatonin undergoes oligomerization reaction with peroxidase + H~2~O~2~, leading to heptameric species. For high reaction times the MALDI/MS data do not show the formation of larger oligomers, but UVโ€“vis spectroscopy indicates that the oligomerization processes proceed. The failure of MALDIโ€TOF in the identification of larger oligomers was related to the chemicalโ€“physical and morphological behavior of melanins.

In the case of UV irradiation, the formation of species originating from the Oโ€ and O~2~ addition to melatonin, which activate new oligomerization channels, has been observed. Copyright ยฉ 2006 John Wiley & Sons, Ltd.


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