Linked Life Data

8195159

Source:http://linkedlifedata.com/resource/pubmed/id/8195159

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1994-6-29
pubmed:abstractText
Metallothioneins (MT) are ubiquitous low molecular weight metal-binding proteins that may act as antioxidants. We examined the sensitivity of NIH 3T3 cells transfected with a plasmid containing mouse metallothionein-I gene (NIH3T3/MT) to the membrane permeant oxidant, tert-butyl hydroperoxide (tBH). NIH3T3/MT cells had a 4-fold increase in intracellular metallothionein as compared to cells transfected with a plasmid containing an inverted gene (NIH3T3/TM). Newly expressed metallothionein appeared to be localized to the cytoplasm as determined by immunofluorescence and confocal microscopy. NIH3T3/MT cells were 6 times more resistant than NIH3T3/TM cells to the cytotoxic effects of tBH. The antioxidant activity of NIH3T3/MT cells was greater than NIH3T3/TM cells, since exposure to tBH resulted in significantly less: (a) thiobarbituric acid-reactive substances and (b) fluorescence after loading cells with the oxidant-sensitive dye, 2'7'-dichlorodihydrofluorescein diacetate. Furthermore, homogenates of NIH3T3/MT cells were more capable of scavenging in vitro generated phenoxyl radicals as quantified by electron spin resonance detection. In contrast, overexpression of cytoplasmic MT did not protect against tBH-induced DNA damage, suggesting that subcellular location of MT is important for its function and that DNA damage is not a key determinant of cytotoxicity. These data provide direct support for an antioxidant role for MT, since physiologically relevant elevations in cytoplasmic MT interfere with tBH-induced cytotoxic peroxidation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
27
pubmed:volume
269
pubmed:geneSymbol
MT-I
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
15238-43
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Cytoplasmic metallothionein overexpression protects NIH 3T3 cells from tert-butyl hydroperoxide toxicity.
pubmed:affiliation
Department of Pharmacology, University of Pittsburgh School of Medicine, Pennsylvania 15261.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't