Linked Life Data

8079344

Source:http://linkedlifedata.com/resource/pubmed/id/8079344

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-10-6
pubmed:abstractText
Manganism, a neurodegenerative disease that can follow chronic exposure to Mn, has been associated with lesions in the basal ganglia and depletion of dopamine and its metabolites in this brain region. Herein, we have tested the hypothesis that oxidation of catechols is a critical component of Mn-induced cytotoxicity. To eliminate confounding metabolic pathways, a nonneuronal cell line, Chinese hamster ovary (CHO) fibroblasts, was transfected with a cDNA for bovine aromatic amino acid decarboxylase, and a high expressing clone was isolated (CHO/AADC). Exposure of wild-type (CHO/WT) or CHO/AADC cultures to L-dopa (62 to 500 microM) resulted in intracellular accumulation of L-dopa or L-dopa and dopamine, respectively, that was concentration-dependent. Intracellular catechol levels in CHO/AADC cells were double those in CHO/WT cultures. No dopac was identified intra- or extracellularly. Addition of MnCl2 (125 to 500 microM) resulted in cytotoxicity that progressed with increasing concentrations of L-dopa or Mn. Neither L-dopa nor MnCl2 alone was toxic at these concentrations, and cytotoxicity was completely abrogated by substitution of L-tyrosine for L-dopa. Although CHO/AADC cultures were more sensitive than CHO/WT to L-dopa and Mn, this was completely accounted for by the differences in intracellular catechol levels between the two cell lines. Preformed melanin or dopac were low-potency cytotoxins only at high MnCl2 concentrations. These results indicate that Mn and intracellular L-dopa and dopamine, but not extracellular dopac or melanin, are potent synergistic cytotoxins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0041-008X
pubmed:author
pubmed:issnType
Print
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
116-22
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Fibroblasts that express aromatic amino acid decarboxylase have increased sensitivity to the synergistic cytotoxicity of L-dopa and manganese.
pubmed:affiliation
Department of Pathology, Duke University Medical Center, Durham, North Carolina 27710.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.