Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026838 (spasticity)
 6,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After incubation of rat cortical cell cultures with the human immunodeficiency virus type 1 (HIV-1) coat protein gp120 for 12 h, cells showed fragmentation of DNA at internucleosomal linkers, the characteristic feature of apoptosis. In a quantitative approach, it was determined that the percentage of DNA fragmentation increased from 7%, in the absence of gp120, to 62% following incubation with 24 ng/ml of gp120. Simultaneously, the percentage of viable cells decreased from 94% to 33%. Memantine (1-amino-3,5-dimethyladamantane), a drug currently used in the therapy of spasticity and Parkinson's disease as well as the NMDA antagonist MK-801 both prevented the effects of gp120 at micromolar concentrations. In human cultured astrocytes, gp120 was ineffective with respect to DNA fragmentation and cell toxicity. From these data, we conclude that the gp120-induced apoptosis may contribute to the neurological complications frequently associated with the immunodeficiency syndrome. The cytoprotective effect of memantine in cortical cell cultures may qualify the drug for the treatment of AIDS-related dementia.
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PMID:gp120 of HIV-1 induces apoptosis in rat cortical cell cultures: prevention by memantine. 142 20

Incubation of highly enriched neurons from rat cerebral cortex with the human immunodeficiency virus type 1 (HIV-1) coat protein gp120 for 18 h results in fragmentation of DNA at internucleosomal linkers, a feature of apoptosis. We report that neurons respond to exposure to gp120 with an increased release of arachidonic acid via activation of phospholipase A2. This process is not inhibited by antagonists of the N-methyl-D-aspartate (NMDA) receptor channels. To investigate the influence of arachidonic acid on the sensitivity of NMDA receptor towards its against, low concentrations of NMDA were coadministered with arachidonic acid. Under these conditions the NMDA-mediated cytotoxicity was enhanced. We conclude that gp120 causes an activation of phospholipase A2, resulting in an increased release of arachidonic acid which in turn sensitizes the NMDA receptor. Two compounds were found to act cytoprotectively against the deleterious effect caused by gp120 on neurons: Memantine [1-amino-3,5-dimethyladamantane] and Flupirtine [2-amino-3-ethoxycarbonylamino-6-(4-fluoro-benzyl-amino)-pyridine maleate]. Both compounds have been found to display a potent cytoprotective effect on neurons treated with the excitatory amino acid NMDA or with the human immunodeficiency virus type 1 (HIV-1) coat protein gp120. The NMDA antagonist Memantine, a drug currently used in the therapy of spasticity and Parkinson's disease, prevented the effects of gp120 at micromolar concentrations. Flupirtine was previously found to be a centrally acting, nonopiate analgesic agent which additionally possesses anticonvulsant and muscle-relaxant activity at doses similar to those producing analgesia. The cytoprotective effect of Flupirtine in vitro was significant (above 10 microM). Considering the fact that both Memantine and Flupirtine display almost no clinical side effects, these drugs may prove useful both in preventing primary infection of brain cells with the HIV virus, as well as in treating the neurological disorders often associated with the immunodeficiency syndrome such as AIDS-related dementia.
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PMID:Neurotoxicity in rat cortical cells caused by N-methyl-D-aspartate (NMDA) and gp120 of HIV-1: induction and pharmacological intervention. 882 91

HIV-related encephalopathy is an important problem in vertically infected children with HIV. Infected infants may manifest early, catastrophic encephalopathy, with loss of brain growth, motor abnormalities, and cognitive dysfunction. Even without evidence of AIDS, infected infants score lower than serorevertors on developmental measures, particularly language acquisition. Children with perinatal or later transfusion-related infection generally are roughly comparable developmentally to their peers until late in their course. Symptoms similar to adult AIDS dementia complex are occasionally seen in adolescents with advanced AIDS, including dementia, bradykinesia, and spasticity. Opportunistic CNS infections such as toxoplasmosis and progressive multifocal leukoencephalopathy are less common in children and adolescents than in adults. Increasing evidence suggests that aggressive antiretroviral treatment may halt or even reverse encephalopathy. Neuroimaging changes may precede or follow clinical manifestations, and include early lenticulostriate vessel echogenicity on cranial ultrasound, calcifying microangiopathy on CT scan, and/or white matter lesions and central atrophy on MRI. Differential diagnosis of neurological dysfunction in an HIV-infected infant includes the effects of maternal substance abuse, other CNS congenital infections, and other causes of early static encephalopathy. Initial entry of HIV into the nervous system occurs very early in infection. The risk of clinical HIV encephalopathy increases with very early age of infection and with high viral loads. Virus is found in microglia and brain derived macrophages, not neurons. The neuronal effect of HIV is probably indirect, with various cytokines implicated. Apoptosis is the presumed mechanism of damage to neurons by HIV.
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PMID:Neurological and developmental effects of HIV and AIDS in children and adolescents. 1155 37