Stephen J. Crocker and Richard Milner contributed equally to this work.
Cell and agonist-specific regulation of genes for matrix metalloproteinases and their tissue inhibitors by primary glial cells
Article first published online: 26 MAY 2006
Journal of Neurochemistry
Volume 98, Issue 3, pages 812–823, August 2006
How to Cite
Crocker, S. J., Milner, R., Pham-Mitchell, N. and Campbell, I. L. (2006), Cell and agonist-specific regulation of genes for matrix metalloproteinases and their tissue inhibitors by primary glial cells. Journal of Neurochemistry, 98: 812–823. doi: 10.1111/j.1471-4159.2006.03927.x
- Issue published online: 19 JUN 2006
- Article first published online: 26 MAY 2006
- Received November 12, 2005; revised manuscript received March 20, 2006; accepted March 20, 2006.
An imbalance in the matrix metalloproteinase (MMP) : tissue inhibitor of MMP (TIMP) ratio may be associated with tissue injury. Here, we studied the regulation of TIMP and MMP gene expression in primary glial cultures to ascertain the factors involved in the regulation of these genes in conditions of inflammatory neuropathology. Astrocytes were found to basally express TIMP-1 and TIMP-3 mRNA while microglia expressed only TIMP-2 mRNA. TIMP-4 mRNA was not detectable in either cell type. Treatment with interferon-α (IFN-α), IFN-γ, interleukin-3 (IL-3), IL-6 or tumor necrosis factor-α (TNF-α) did not alter expression of the TIMP genes. However, in astrocytes, but not in microglia, serum, IL-1β or lipopolysaccharide (LPS) evoked a dose- and time-dependent increase in TIMP-1 mRNA and a coincident down-regulation of the TIMP-3 gene. Astrocytes were found to express mRNA constitutively for MMPs -3, -11 and -14. In contrast, microglia expressed only MMP-12 mRNA under basal conditions. IL-1β enhanced MMP-3 mRNA levels while LPS increased the MMP-3, -9, -12, -13 and -14 mRNAs. Our findings reveal that regulatory control of TIMP and MMP gene expression by glial cells is agonist- and cell-type specific, and suggest that innate immune signals govern the temporal and spatial expression patterns of TIMP and MMP genes in neuroinflammatory conditions of the CNS.