Linked Life Data

12401955

Source:http://linkedlifedata.com/resource/pubmed/id/12401955

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
2002-10-28
pubmed:abstractText
Astrocytes in subcortical regions of the mammalian brain progressively accumulate iron-rich, autofluorecent cytoplasmic inclusions as a function of aging. Cysteamine (CSH) accelerates the appearance of this senescent glial phenotype in situ and in primary rat astroglial cultures. Porphyrins have been implicated as the source of orange-red autofluorescence in these glial inclusions. Yet, CSH has been shown to suppress porphyrin-heme biosynthesis in cultured astroglia. To determine whether porphyrin biosynthesis or sequestration participates in the biogenesis of these glial inclusions, the porphyrin precursor, (3)H-delta-aminolevulinic acid ((3)H-ALA) was administered to CSH-exposed and control rat astroglial cultures followed by light and electron microscopic autoradiography. Control cultures exhibited faint orange-red autofluorescence, intense (3)H-ALA labeling, numerous normal mitochondria and few cytoplasmic inclusions. In these cells, (3)H-ALA labeling largely occurred over normal mitochondria. The CSH-treated astroglia exhibited diminished (3)H-ALA labeling and contained numerous orange-red autofluorescent inclusions. The latter manifested internal compartments delimited by double membranes characteristic of damaged mitochondria. The complement of normal mitochondria in the CSH-exposed cells was markedly reduced. In the CSH-treated cells, (3)H-ALA labeling predominated over the large multi-compartmental inclusions. CSH attenuates de novo porphyrin-heme biosynthesis in astroglia but may induce punctate orange-red autofluorescence in the cytoplasm of these cells by promoting large numbers of damaged, porphyrin-containing mitochondria to form tight aggregates within the nascent gliosomes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0378-5866
pubmed:author
pubmed:copyrightInfo
Copyright 2002 S. Karger AG, Basel
pubmed:issnType
Print
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
169-76
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Role of porphyrin sequestration in the biogenesis of iron-laden astrocytic inclusions in primary culture.
pubmed:affiliation
Bloomfield Center for Research in Aging, Lady Davis Institute, Sir Mortimer B. Davis Jewish General Hospital, Montreal, Quebec, Canada. hyman.schipper@mcgill.ca
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't