Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-2
pubmed:abstractText
Toxic effects of HIV-1 proteins contribute to altered function and decreased survival of select populations of neurons in HIV-1-infected brain. One such HIV-1 protein, Tat, can activate calcium release from IP3-sensitive intracellular pools, induce calcium influx in neural cells, and, as a result, can increase neuronal cell death. Here, we provide evidence that Tat potentiates excitatory amino acid (glutamate and NMDA) triggered calcium flux, as well as glutamate- and staurosporine-mediated neurotoxicity. Calcium flux in cultured rat hippocampal neurons triggered by the transient application of glutamate or NMDA was facilitated by pre-exposure to Tat. Facilitation of glutamate-triggered calcium flux by Tat was prevented by inhibitors of ADP-ribosylation of G(i)/G(o) proteins (pertussis toxin), protein kinase C (H7 and bisindolymide), and IP3-mediated calcium release (xestospongin C), but was not prevented by an activator of G(s) (cholera toxin) or an inhibitor of protein kinase A (H89). Facilitation of NMDA-triggered calcium flux by Tat was reversed by inhibitors of tyrosine kinase (genestein and herbimycin A) and by an inhibitor of NMDA receptor function (zinc). Tat increased 32P incorporation into NMDA receptor subunits NR2A and NR2B and this effect was blocked by genestein. Subtoxic concentrations of Tat combined with subtoxic concentrations of glutamate or staurosporine increased neuronal cell death significantly. Together, these findings suggest that NMDA receptors play an important role in Tat neurotoxicity and the mechanisms identified may provide additional therapeutic targets for the treatment of HIV-1 associated dementia.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
78
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
457-67
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11483648-Animals, pubmed-meshheading:11483648-Apoptosis, pubmed-meshheading:11483648-Brain Chemistry, pubmed-meshheading:11483648-Calcium, pubmed-meshheading:11483648-Cells, Cultured, pubmed-meshheading:11483648-Cerebral Cortex, pubmed-meshheading:11483648-Dose-Response Relationship, Drug, pubmed-meshheading:11483648-Enzyme Inhibitors, pubmed-meshheading:11483648-Gene Products, tat, pubmed-meshheading:11483648-Glutamic Acid, pubmed-meshheading:11483648-Hippocampus, pubmed-meshheading:11483648-Models, Biological, pubmed-meshheading:11483648-Neurons, pubmed-meshheading:11483648-Phosphorylation, pubmed-meshheading:11483648-Protein Subunits, pubmed-meshheading:11483648-Rats, pubmed-meshheading:11483648-Rats, Sprague-Dawley, pubmed-meshheading:11483648-Receptors, N-Methyl-D-Aspartate, pubmed-meshheading:11483648-Regression Analysis, pubmed-meshheading:11483648-Spectrometry, Fluorescence, pubmed-meshheading:11483648-Staurosporine, pubmed-meshheading:11483648-Synaptosomes
pubmed:year
2001
pubmed:articleTitle
HIV-1 Tat through phosphorylation of NMDA receptors potentiates glutamate excitotoxicity.
pubmed:affiliation
Laboratory of Neurosciences, National Institute on Aging, Baltimore, Maryland, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't