title: Differential regulation of MMP-13 by chemical modified tetracyclines in osteoblasts.
abstract: Tetracyclines have been shown to regulate matrix metalloproteinase (MMP) expression in numerous cell types with various periodontal disease models. MMP-13, or collagenase-3, has been shown to be induced by a number of osteotropic cytokines and hormones in osteoblastic cells. In this study, we studied MMP-13 gene expression and regulation in osteoblasts by chemically modified tetracyclines (CMTs). Preliminary cytotoxicity studies indicated that 1-10 microg/ml of CMT-8 did not result in statistically significant cell death. Additional fluorescent microscopy experiments indicated that CMT-8 but not CMT-5 had a nuclear distribution within one hour of addition CMTs. Using primary rat calvarial osteoblastic cells obtained from 21-day old neonatal rats, we determined MMP-13 gene expression when stimulated by parathyroid hormone (PTH), interleukin (IL)-1b, or tumour necrosis factor (TNF)-alpha in the presence or absence of CMT-8 or -5. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) using total RNA was used to determine relative expression of MMP-13 compared to glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a constitutively expressed housekeeping gene. Results indicate that all agents were consistently able to induce MMP-13 expression in primary calvarial osteoblastic cells. However, CMT-8 inhibited MMP-13 expression from IL-1b and PTH stimulated cells while having little effect on TNF-alpha stimulated MMP-13 expression. In contrast, CMT-5 only inhibited PTH stimulated MMP-13 expression, with no effect on IL-1b or TNF-alpha stimulated MMP-13 expression. These results suggest that CMT-8 and CMT-5 may differentially affect cell signaling pathways in osteoblastic cells that mediate MMP-13 gene expression.
authors.affiliation: Department of Periodontics and Endodontics, State University of New York at Buffalo, Buffalo, New York, USA.
authors.forename: Keith
authors.initials: K
authors.lastname: Kirkwood
authors.forename: Thomas
authors.initials: T
authors.lastname: Martin
authors.forename: Kimberly
authors.initials: K
authors.lastname: Agnello
authors.forename: Young Joon
authors.initials: YJ
authors.lastname: Kim
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D017364:Collagenases / Q000187:drug effects* / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000187:drug effects / Q000235:genetics; D007375:Interleukin-1 / Q000494:pharmacology; D053509:Matrix Metalloproteinase 13; D008856:Microscopy, Fluorescence; D010006:Osteoblasts / Q000187:drug effects* / Q000201:enzymology; D010281:Parathyroid Hormone / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000235:genetics; D013754:Tetracyclines / Q000493:pharmacokinetics / Q000494:pharmacology*; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: C478158:CMT-5 compound; D007375:Interleukin-1; D010281:Parathyroid Hormone; D013754:Tetracyclines; D014409:Tumor Necrosis Factor-alpha; C117153:tetracycline CMT-8; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D017364:Collagenases; D053509:Matrix Metalloproteinase 13; C507083:Mmp13 protein, rat