Differential regulation of gelatinase A and B and TIMP-1 and -2 by TNFalpha and HIV virions in astrocytes.
Changes in the fine balance between matrix metalloproteinases and their tissue inhibitors, which drives extracellular matrix turnover, may be critical to central nervous system inflammation in HIV infection as well as in neurotoxicity. Although they do not produce virus when infected by HIV, astrocytes may be directly affected by the virion, because some viral proteins are known to transduce signaling in brain cells and are also sensitive to the major proinflammatory cytokine TNFalpha. We therefore studied the effects of HIV and TNFalpha on MMP-2, MMP-9 and their inhibitors, TIMP-1 and TIMP-2, in astrocytes, by zymography and ELISA, respectively, or by RT-PCR for both of them. HIV slightly increased the production of pro-MMP-2 and pro-MMP-9 by astrocytes, in a dose-dependent manner. TNFalpha strongly induced pro-MMP-9. TIMP-1 and TIMP-2 levels were affected only slightly, if at all, by HIV and TNFalpha. Thus, astrocyte/HIV contact may lead to extracellular matrix activation, which may be strongly amplified by the inflammatory response. Our data strongly suggest that, besides their physiological production of MMP-2, astrocytes would be a major source of MMP-9 in the inflamed brain.
Laboratoire de Neuro-Immuno-Virologie, Service de Neurovirologie, Commissariat à l'Energie Atomique and Université Paris-Sud, Centre de Recherches du Service de Santé des Armées, Institut Paris-Sud Cytokines, Ecole Pratique des Hautes Etudes, France.
Thierry
T
Lévêque
Gwenaëlle
G
Le Pavec
Agnès
A
Boutet
Marc
M
Tardieu
Dominique
D
Dormont
Gabriel
G
Gras
D001253:Astrocytes / Q000187:drug effects* / Q000201:enzymology / Q000821:virology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006678:HIV / Q000502:physiology*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000235:genetics / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000378:metabolism*; D061965:Matrix Metalloproteinase Inhibitors; D009490:Neurosecretory Systems / Q000502:physiology; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000235:genetics / Q000378:metabolism*; D019716:Tissue Inhibitor of Metalloproteinase-2 / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014771:Virion / Q000502:physiology
D061965:Matrix Metalloproteinase Inhibitors; D019715:Tissue Inhibitor of Metalloproteinase-1; D014409:Tumor Necrosis Factor-alpha; D019716:Tissue Inhibitor of Metalloproteinase-2; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9