Neonatal intrahippocampal HIV-1 protein Tat(1-86) injection: neurobehavioral alterations in the absence of increased inflammatory cytokine activation.
Int J Dev Neurosci
; 38: 195-203, 2014 Nov.
Article
em En
| MEDLINE
| ID: mdl-25285887
ABSTRACT
Pediatric AIDS caused by human immunodeficiency virus type 1 (HIV-1) remains one of the leading worldwide causes of childhood morbidity and mortality. HIV-1 proteins, such as Tat and gp120, are believed to play a crucial role in the neurotoxicity of pediatric HIV-1 infection. Detrimental effects on development, behavior, and neuroanatomy follow neonatal exposure to the HIV-1 viral toxins Tat1-72 and gp120. The present study investigated the neurobehavioral effects induced by the HIV-1 neurotoxic protein Tat1-86, which encodes the first and second exons of the Tat protein. In addition, the potential effects of HIV-1 toxic proteins Tat1-86 and gp120 on inflammatory pathways were examined in neonatal brains. Vehicle, 25 µg Tat1-86 or 100 ng gp120 was injected into the hippocampus of male Sprague-Dawley pups on postnatal day 1 (PD1). Tat1-86 induced developmental neurotoxic effects, as witnessed by delays in eye opening, delays in early reflex development and alterations in prepulse inhibition (PPI) and between-session habituation of locomotor activity. Overall, the neurotoxic profile of Tat1-86 appeared more profound in the developing nervous system in vivo relative to that seen with the first exon encoded Tat1-72 (Fitting et al., 2008b), as noted on measures of eye opening, righting reflex, and PPI. Neither the direct PD1 CNS injection of the viral HIV-1 protein variant Tat1-86, nor the HIV-1 envelope protein gp120, at doses sufficient to induce neurotoxicity, necessarily induced significant expression of the inflammatory cytokine IL-1ß or inflammatory factors NF-κß and I-κß. The findings agree well with clinical observations that indicate delays in developmental milestones of pediatric HIV-1 patients, and suggest that activation of inflammatory pathways is not an obligatory response to viral protein-induced neurotoxicity that is detectable with behavioral assessments. Moreover, the amino acids encoded by the second tat exon may have unique actions on the developing hippocampus.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Deficiências do Desenvolvimento
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Citocinas
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Sistemas de Transporte de Aminoácidos Neutros
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Hipocampo
Tipo de estudo:
Clinical_trials
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Prognostic_studies
Limite:
Animals
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Female
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Humans
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Male
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Pregnancy
Idioma:
En
Revista:
Int J Dev Neurosci
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Estados Unidos