Pharmacological, behavioural and mechanistic analysis of HIV-1 gp120 induced painful neuropathy

Pain. 2007 Dec 15;133(1-3):47-63. doi: 10.1016/j.pain.2007.02.015. Epub 2007 Apr 12.

Abstract

A painful neuropathy is frequently observed in people living with human immunodeficiency virus type 1 (HIV-1). The HIV coat protein, glycoprotein 120 (gp120), implicated in the pathogenesis of neurological disorders associated with HIV, is capable of initiating neurotoxic cascades via an interaction with the CXCR4 and/or CCR5 chemokine receptors, which may underlie the pathogenesis of HIV-associated peripheral neuropathic pain. In order to elucidate the mechanisms underlying HIV-induced painful peripheral neuropathy, we have characterised pathological events in the peripheral and central nervous system following application of HIV-1 gp120 to the rat sciatic nerve. Perineural HIV-1 gp120 treatment induced a persistent mechanical hypersensitivity (44% decrease from baseline), but no alterations in sensitivity to thermal or cold stimuli, and thigmotactic (anxiety-like) behaviour in the open field. The mechanical hypersensitivity was sensitive to systemic treatment with gabapentin, morphine and the cannabinoid WIN 55,212-2, but not with amitriptyline. Immunohistochemical studies reveal: decreased intraepidermal nerve fibre density, macrophage infiltration into the peripheral nerve at the site of perineural HIV-1 gp120; changes in sensory neuron phenotype including expression of activating transcription factor 3 (ATF3) in 27% of cells, caspase-3 in 25% of cells, neuropeptide Y (NPY) in 12% of cells and galanin in 13% of cells and a spinal gliosis. These novel findings suggest that this model is not only useful for the elucidation of mechanisms underlying HIV-1-related peripheral neuropathy but may prove useful for preclinical assessment of drugs for the treatment of HIV-1 related peripheral neuropathic pain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activating Transcription Factor 3 / metabolism
  • Analgesics / therapeutic use
  • Analysis of Variance
  • Animals
  • Behavior, Animal / drug effects
  • Behavior, Animal / physiology*
  • Caspase 3
  • Disease Models, Animal
  • Exploratory Behavior / drug effects
  • Exploratory Behavior / physiology
  • GAP-43 Protein / metabolism
  • Gene Expression Regulation / drug effects
  • HIV Envelope Protein gp120*
  • Macrophages / drug effects
  • Male
  • Microscopy, Electron, Transmission / methods
  • Pain Measurement / methods
  • Pain Threshold / drug effects
  • Rats
  • Rats, Wistar
  • Reaction Time / drug effects
  • Reaction Time / physiology
  • Sciatica / chemically induced*
  • Sciatica / drug therapy
  • Sciatica / pathology
  • Sciatica / physiopathology*
  • Ubiquitin Thiolesterase / metabolism

Substances

  • Activating Transcription Factor 3
  • Analgesics
  • Atf3 protein, rat
  • GAP-43 Protein
  • HIV Envelope Protein gp120
  • gp120 protein, Human immunodeficiency virus 1
  • UCHL1 protein, rat
  • Ubiquitin Thiolesterase
  • Caspase 3