HIV-induced metalloproteinase processing of the chemokine stromal cell derived factor-1 causes neurodegeneration

Nat Neurosci. 2003 Oct;6(10):1064-71. doi: 10.1038/nn1127. Epub 2003 Sep 21.

Abstract

The mechanisms of neurodegeneration that result in human immunodeficiency virus (HIV) type 1 dementia have not yet been identified. Here, we report that HIV-infected macrophages secrete the zymogen matrix metalloproteinase-2 (MMP-2), which is activated by exposure to MT1-MMP on neurons. Stromal cell-derived factor 1 alpha (SDF-1), a chemokine overexpressed by astrocytes during HIV infection, was converted to a highly neurotoxic protein after precise proteolytic processing by active MMP-2, which removed the N-terminal tetrapeptide. Implantation of cleaved SDF-1(5-67) into the basal ganglia of mice resulted in neuronal death and inflammation with ensuing neurobehavioral deficits that were abrogated by neutralizing antibodies to SDF-1 and an MMP inhibitor drug. Hence, this study identifies a new in vivo neurotoxic pathway in which cleavage of a chemokine by an induced metalloproteinase results in neuronal apoptosis that leads to neurodegeneration.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS Dementia Complex / enzymology*
  • AIDS Dementia Complex / etiology
  • AIDS Dementia Complex / physiopathology
  • Animals
  • Antibodies / pharmacology
  • Astrocytes / metabolism
  • Cell Line
  • Chemokine CXCL12
  • Chemokines, CXC / antagonists & inhibitors
  • Chemokines, CXC / metabolism
  • Chemokines, CXC / toxicity*
  • Disease Models, Animal
  • Encephalitis / chemically induced
  • Encephalitis / enzymology
  • Encephalitis / physiopathology
  • Enzyme Inhibitors / pharmacology
  • HIV-1 / metabolism
  • HIV-1 / pathogenicity
  • Humans
  • Macrophages / enzymology
  • Macrophages / metabolism
  • Matrix Metalloproteinase 2 / metabolism*
  • Matrix Metalloproteinase Inhibitors
  • Mice
  • Neostriatum / drug effects
  • Neostriatum / pathology
  • Neostriatum / physiopathology
  • Nerve Degeneration / chemically induced
  • Nerve Degeneration / enzymology*
  • Nerve Degeneration / virology
  • Neurotoxins / metabolism
  • Neurotoxins / toxicity*
  • Peptide Fragments / metabolism
  • Peptide Fragments / toxicity

Substances

  • Antibodies
  • CXCL12 protein, human
  • Chemokine CXCL12
  • Chemokines, CXC
  • Cxcl12 protein, mouse
  • Enzyme Inhibitors
  • Matrix Metalloproteinase Inhibitors
  • Neurotoxins
  • Peptide Fragments
  • Matrix Metalloproteinase 2