The alpha7-nicotinic receptor contributes to gp120-induced neurotoxicity: implications in HIV-associated neurocognitive disorders

Sci Rep. 2018 Jan 29;8(1):1829. doi: 10.1038/s41598-018-20271-x.

Abstract

Currently, there are no specific therapies to treat HIV-1 associated neurocognitive disorders (HAND). The HIV-1 envelope, gp120, induces neuropathological changes similar to those in HAND patients; furthermore, it triggers an upregulation of the α7-nicotinic acetylcholine receptor (α7-nAChR), facilitating intracellular calcium overload and neuronal cell death. Using a gp120IIIB-transgenic mouse (gp120-tgm) model, we demonstrate that α7-nAChRs are upregulated on striatal neurons. Activation of α7-nAChRs leads to an increase in both intracellular calcium and percentage of apoptotic cells, which can be abrogated by antagonizing the receptor, suggesting a role for α7-nAChRs in gp120-induced neurotoxicity. Moreover, we demonstrate for the first time that gp120-tgm have learning deficiencies on a striatum-dependent behavioral task. They also show locomotor deficiencies, which improved with α7-nAChR antagonists, further supporting a role for this receptor in gp120-induced neurotoxicity. Together, these results uncover a new mechanism through which gp120-induced modulation of α7-nAChRs in the striatum can contribute to HAND development.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Cell Death / physiology
  • Corpus Striatum / metabolism
  • Female
  • HIV Envelope Protein gp120 / metabolism*
  • HIV Infections / metabolism*
  • HIV-1 / metabolism*
  • Hippocampus / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neurocognitive Disorders / metabolism*
  • Neurons / metabolism*
  • Neurotoxicity Syndromes / metabolism*
  • Receptors, Nicotinic / metabolism
  • alpha7 Nicotinic Acetylcholine Receptor / metabolism*

Substances

  • HIV Envelope Protein gp120
  • Receptors, Nicotinic
  • alpha7 Nicotinic Acetylcholine Receptor