Linked Life Data

16946714

Source:http://linkedlifedata.com/resource/pubmed/id/16946714

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-1-17
pubmed:abstractText
The human skin holds the capacity for autocrine processing of the proopiomelanocortin (POMC)-derived peptides. Recent data demonstrated the presence and functionality of ACTH, alpha- and beta-melanocyte-stimulating hormone (MSH), and beta-endorphin in the regulation of skin pigmentation, and a role has been put forward for alpha-MSH as an effective antioxidant. In patients with vitiligo, decreased epidermal POMC processing and low alpha-MSH levels were documented previously. These patients accumulate hydrogen peroxide (H2O2) in the 10(-3) M range in their epidermis. Therefore, we examined the involvement of H2O2 on POMC-derived peptides as possible targets for oxidation by this reactive oxygen species. To address this, we employed immunofluorescence labelling, dot blot analysis, Fourier transform Raman spectroscopy, functionality studies, and computer simulation of the peptide structures. We demonstrate H2O2-mediated oxidation of epidermal ACTH, alpha-MSH, and beta-endorphin in vitiligo owing to oxidation of methionine residues in the sequences of these peptides. Moreover, we show that oxidized beta-endorphin loses its function in the promotion of pigmentation in melanocytes. These changes are reversible upon the reduction of H2O2 levels by a pseudocatalase PC-KUS. Moreover, oxidation of alpha-MSH can be prevented by the formation of a 1:1 complex with the abundant cofactor (6R)-L-erythro-5,6,7,8-tetrahydrobiopterin. Thus, using vitiligo, we demonstrate that H2O2 can affect pigmentation via epidermal POMC peptide redox homeostasis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1523-1747
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
127
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
411-20
pubmed:meshHeading
pubmed-meshheading:16946714-Adrenocorticotropic Hormone, pubmed-meshheading:16946714-Biopterin, pubmed-meshheading:16946714-Catalase, pubmed-meshheading:16946714-Cells, Cultured, pubmed-meshheading:16946714-Computer Simulation, pubmed-meshheading:16946714-Epidermis, pubmed-meshheading:16946714-Fourier Analysis, pubmed-meshheading:16946714-Humans, pubmed-meshheading:16946714-Hydrogen Peroxide, pubmed-meshheading:16946714-Melanins, pubmed-meshheading:16946714-Models, Biological, pubmed-meshheading:16946714-Oxidation-Reduction, pubmed-meshheading:16946714-Oxidative Stress, pubmed-meshheading:16946714-Peptide Fragments, pubmed-meshheading:16946714-Pro-Opiomelanocortin, pubmed-meshheading:16946714-Skin Pigmentation, pubmed-meshheading:16946714-Spectrum Analysis, Raman, pubmed-meshheading:16946714-Vitiligo, pubmed-meshheading:16946714-alpha-MSH, pubmed-meshheading:16946714-beta-Endorphin
pubmed:year
2007
pubmed:articleTitle
Oxidative stress via hydrogen peroxide affects proopiomelanocortin peptides directly in the epidermis of patients with vitiligo.
pubmed:affiliation
Clinical and Experimental Dermatology/Department of Biomedical Sciences, University of Bradford, Bradford, UK.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't