Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2004-4-1
pubmed:abstractText
Reactive astrocytes frequently surround degenerating motor neurons in patients and transgenic animal models of amyotrophic lateral sclerosis (ALS). We report here that reactive astrocytes in the ventral spinal cord of transgenic ALS-mutant G93A superoxide dismutase (SOD) mice expressed nerve growth factor (NGF) in regions where degenerating motor neurons expressed p75 neurotrophin receptor (p75(NTR)) and were immunoreactive for nitrotyrosine. Cultured spinal cord astrocytes incubated with lipopolysaccharide (LPS) or peroxynitrite became reactive and accumulated NGF in the culture medium. Reactive astrocytes caused apoptosis of embryonic rat motor neurons plated on the top of the monolayer. Such motor neuron apoptosis could be prevented when either NGF or p75(NTR) was inhibited with blocking antibodies. In addition, nitric oxide synthase inhibitors were also protective. Exogenous NGF stimulated motor neuron apoptosis only in the presence of a low steady state concentration of nitric oxide. NGF induced apoptosis in motor neurons from p75(NTR +/+) mouse embryos but had no effect in p75(NTR -/-) knockout embryos. Culture media from reactive astrocytes as well as spinal cord lysates from symptomatic G93A SOD mice-stimulated motor neuron apoptosis, but only when incubated with exogenous nitric oxide. This effect was prevented by either NGF or p75(NTR) blocking-antibodies suggesting that it might be mediated by NGF and/or its precursor forms. Our findings show that NGF secreted by reactive astrocytes induce the death of p75-expressing motor neurons by a mechanism involving nitric oxide and peroxynitrite formation. Thus, reactive astrocytes might contribute to the progressive motor neuron degeneration characterizing ALS.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
89
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
464-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:15056289-Amyotrophic Lateral Sclerosis, pubmed-meshheading:15056289-Animals, pubmed-meshheading:15056289-Antibodies, pubmed-meshheading:15056289-Apoptosis, pubmed-meshheading:15056289-Astrocytes, pubmed-meshheading:15056289-Cell Extracts, pubmed-meshheading:15056289-Cells, Cultured, pubmed-meshheading:15056289-Culture Media, Conditioned, pubmed-meshheading:15056289-Disease Models, Animal, pubmed-meshheading:15056289-Humans, pubmed-meshheading:15056289-Mice, pubmed-meshheading:15056289-Mice, Transgenic, pubmed-meshheading:15056289-Motor Neurons, pubmed-meshheading:15056289-Nerve Growth Factor, pubmed-meshheading:15056289-Nitric Oxide, pubmed-meshheading:15056289-Peroxynitrous Acid, pubmed-meshheading:15056289-Rats, pubmed-meshheading:15056289-Receptor, Nerve Growth Factor, pubmed-meshheading:15056289-Receptors, Nerve Growth Factor, pubmed-meshheading:15056289-Spinal Cord, pubmed-meshheading:15056289-Superoxide Dismutase
pubmed:year
2004
pubmed:articleTitle
Astrocytic production of nerve growth factor in motor neuron apoptosis: implications for amyotrophic lateral sclerosis.
pubmed:affiliation
Departamento de Neurobiología Celular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't