Regulation of matrix metalloproteinase-1, -3, and -9 in Mycobacterium tuberculosis-dependent respiratory networks by the rapamycin-sensitive PI3K/p70S6K cascade
Regulation of matrix metalloproteinase-1, -3, and -9 in Mycobacterium tuberculosis-dependent respiratory networks by the rapamycin-sensitive PI3K/p70S6K cascade
This study was designed to investigate the role of the phosphatidyl inositol 3-kinase (PI3K)/AKT/p70S6K signaling path on regulation of primary normal human bronchial epithelial cell-derived matrix metalloproteinase (MMP)-1, -3, and -9 expression in tuberculosis (TB). These MMPs are key in pathological extracellular matrix degradation in TB. Normal human bronchial epithelials were stimulated with conditioned medium from monocytes infected with virulent TB (CoMTb) and components of the PI3K/AKT signaling pathway blocked using specific chemical inhibitors and siRNA. MMP gene expression was measured by RT-PCR and secretion by ELISA, luminex, or zymography. Phospho-p70 S6K was detected by Western blot analysis and activity blocked by rapamycin. Chemical blockade of the proximal catalytic PI3K p110 subunit augmented MMP-1 and MMP-9 in a dose-dependent manner (all P<0.001) but suppressed MMP-3 (P<0.01). Targeted siRNA studies identified the p110? isoform as key causing 5-fold increase in TB network-dependent MMP-1 secretion to 4900 ± 1100 pg/ml. Specific inhibition of the AKT node suppressed all 3 MMPs. Phospho-p70S6K was identified in the cellular model, and rapamycin, a p70S6K inhibitor, inhibited MMP-1 (P<0.001) and MMP-3 (P<0.01) but not MMP-9. Controls were epithelial cells that were unstimulated or exposed to conditioned medium from monocytes not exposed to TB. In summary, blockade of the proximal PI3K catalytic subunit increases MMP-1 and MMP-9, whereas rapamycin decreased both MMP-1 and MMP-3. The regulation of the PI3K path in TB is complex, MMP specific, and a potential immunotherapeutic target in diseases characterized by tissue destruction.—Singh, S., Saraiva, L., Elkington, P. T. G., Friedland, J. S. Regulation of matrix metalloproteinase-1, -3, and -9 in Mycobacterium tuberculosis-dependent respiratory networks by the rapamycin-sensitive PI 3-kinase/p70S6K cascade
85-93
Singh, S.
a9cd7e50-e572-4cba-a98d-f3f73372097b
Saraiva, L.
a44071de-689c-4a91-bff0-708ccefd3908
Elkington, P.T.
60828c7c-3d32-47c9-9fcc-6c4c54c35a15
Friedland, J.S.
e64a7af8-b969-4426-82e6-5ebe819799c9
January 2014
Singh, S.
a9cd7e50-e572-4cba-a98d-f3f73372097b
Saraiva, L.
a44071de-689c-4a91-bff0-708ccefd3908
Elkington, P.T.
60828c7c-3d32-47c9-9fcc-6c4c54c35a15
Friedland, J.S.
e64a7af8-b969-4426-82e6-5ebe819799c9
Singh, S., Saraiva, L., Elkington, P.T. and Friedland, J.S.
(2014)
Regulation of matrix metalloproteinase-1, -3, and -9 in Mycobacterium tuberculosis-dependent respiratory networks by the rapamycin-sensitive PI3K/p70S6K cascade.
The FASEB Journal, 28 (1), .
(doi:10.1096/fj.13-235507).
Abstract
This study was designed to investigate the role of the phosphatidyl inositol 3-kinase (PI3K)/AKT/p70S6K signaling path on regulation of primary normal human bronchial epithelial cell-derived matrix metalloproteinase (MMP)-1, -3, and -9 expression in tuberculosis (TB). These MMPs are key in pathological extracellular matrix degradation in TB. Normal human bronchial epithelials were stimulated with conditioned medium from monocytes infected with virulent TB (CoMTb) and components of the PI3K/AKT signaling pathway blocked using specific chemical inhibitors and siRNA. MMP gene expression was measured by RT-PCR and secretion by ELISA, luminex, or zymography. Phospho-p70 S6K was detected by Western blot analysis and activity blocked by rapamycin. Chemical blockade of the proximal catalytic PI3K p110 subunit augmented MMP-1 and MMP-9 in a dose-dependent manner (all P<0.001) but suppressed MMP-3 (P<0.01). Targeted siRNA studies identified the p110? isoform as key causing 5-fold increase in TB network-dependent MMP-1 secretion to 4900 ± 1100 pg/ml. Specific inhibition of the AKT node suppressed all 3 MMPs. Phospho-p70S6K was identified in the cellular model, and rapamycin, a p70S6K inhibitor, inhibited MMP-1 (P<0.001) and MMP-3 (P<0.01) but not MMP-9. Controls were epithelial cells that were unstimulated or exposed to conditioned medium from monocytes not exposed to TB. In summary, blockade of the proximal PI3K catalytic subunit increases MMP-1 and MMP-9, whereas rapamycin decreased both MMP-1 and MMP-3. The regulation of the PI3K path in TB is complex, MMP specific, and a potential immunotherapeutic target in diseases characterized by tissue destruction.—Singh, S., Saraiva, L., Elkington, P. T. G., Friedland, J. S. Regulation of matrix metalloproteinase-1, -3, and -9 in Mycobacterium tuberculosis-dependent respiratory networks by the rapamycin-sensitive PI 3-kinase/p70S6K cascade
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Accepted/In Press date: January 2013
e-pub ahead of print date: 27 September 2013
Published date: January 2014
Organisations:
Clinical & Experimental Sciences
Identifiers
Local EPrints ID: 359641
URI: http://eprints.soton.ac.uk/id/eprint/359641
ISSN: 0892-6638
PURE UUID: f40a4b1c-1816-4c6c-b95d-63253141d19c
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Date deposited: 07 Nov 2013 14:28
Last modified: 15 Mar 2024 03:43
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Author:
S. Singh
Author:
L. Saraiva
Author:
J.S. Friedland
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