Linked Life Data

9758419

Source:http://linkedlifedata.com/resource/pubmed/id/9758419

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1998-12-23
pubmed:abstractText
We have previously shown an imbalance of the antioxidant system in some cultures of normal melanocytes from patients with melanoma. In order to evaluate if the alteration of the antioxidants could be the basis of an increased sensitivity to exposure to peroxidative agents, in cultured melanocytes from normal individuals (n = 11) and from patients with melanoma (n = 11), superoxide dismutase and catalase activities were evaluated by spectrophotometer, and the levels of vitamin E and of the polyunsaturated fatty acid of cell membranes were determined by gas chromatography mass spectrometry. In 5 out of the 11 cultures of melanocytes from melanoma patients, with respect to those from normal individuals, a significant decrease of catalase activity (Cat) associated with an increase of vitamin E (Vit E) concentration was found, whereas no significant modification of superoxide dismutase activity (SOD) was observed. A wide range of variability was detected in the percentage of the polyunsaturated fatty acids of the cell membranes and a correlation was found between the ratio SOD/Cat and the percentage of linoleic acid, indicating that the imbalance of the enzymatic antioxidants leads to a lipoperoxidative process. The electron microscopic examination of these cultures revealed many microvilli in the plasma membranes and nuclear infoldings and in the cytoplasm light vacuoles. Moreover some cells contained several dense bodies with a round shape and numerous spherical lamellae possibly representing immature melanosomes. Treatment with cumene hydroperoxide between 0.66 and 20 microM did not produce a significant modification of cell viability in melanocytes from normal individuals. On the contrary in melanocytes from melanoma patients correlated with the ratio Vit E/Cat, considered as a parameter of the antioxidant imbalance, a stimulatory effect was observed at 0.66 microM CUH and a cytotoxic effect at 20 microM. In conclusion our results suggest that a constitutional alteration of the scavenger system could be present in normal melanocytes from melanoma patients and that this could be the basis for an increased sensitivity to pro-oxidant agents.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0906-6705
pubmed:author
pubmed:issnType
Print
pubmed:volume
7
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
205-12
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Increased sensitivity to peroxidizing agents is correlated with an imbalance of antioxidants in normal melanocytes from melanoma patients.
pubmed:affiliation
Medical Genetic, University La Sapienza, Rome, Italy.
pubmed:publicationType
Journal Article