title: Induction of matrix metalloproteinase-8 in human fibroblasts by basic calcium phosphate and calcium pyrophosphate dihydrate crystals: effect of phosphocitrate.
abstract: Although matrix metalloproteinase-8 (MMP-8) was regarded as the exclusive product of the neutrophils, recent studies have shown that it is also expressed in articular chondrocytes, rheumatoid synovial fibroblasts and endothelial cells. Our aim was to determine the expression of MMP-8 in human fibroblasts (HF) by reverse transcription/polymerase chain reaction (RT/PCR). Northern and Western blotting methods and MMP-8 activity assay. We have shown the expression of MMP-8 in HF and its dose-dependent upregulation by basic calcium phosphate (BCP) and calcium pyrophosphate dihydrate (CPPD) crystals which are markers of severe joint degeneration in osteoarthritis. These effects require new protein synthesis and are reversed by phosphocitrate (PC). The results also show that this fibroblast MMP-8 is distinct from the neutrophil MMP-8 and from the fibroblast MMP-1. These results indicate that MMP-8 may play a significant role in the pathogenic effects of the crystals in osteoarthritis.
authors.affiliation: Research Service & GRECC, Geriatric Research, Education, and Clinical Center, VA Medical Center, Miami, Florida, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Reuben
authors.forename: L
authors.initials: L
authors.lastname: Wenger
authors.forename: M
authors.initials: M
authors.lastname: Cruz
authors.forename: H S
authors.initials: HS
authors.lastname: Cheung
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015152:Blotting, Northern / Q000379:methods; D015153:Blotting, Western / Q000379:methods; D002130:Calcium Phosphates / Q000494:pharmacology*; D002131:Calcium Pyrophosphate / Q000494:pharmacology*; D002478:Cells, Cultured; D002951:Citrates / Q000494:pharmacology*; D017364:Collagenases / Q000235:genetics; D003460:Crystallization; D003513:Cycloheximide / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004318:Doxycycline / Q000494:pharmacology; D004790:Enzyme Induction; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D006801:Humans; D020781:Matrix Metalloproteinase 1 / Q000235:genetics; D053509:Matrix Metalloproteinase 13; D020784:Matrix Metalloproteinase 8 / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D011500:Protein Synthesis Inhibitors; D015854:Up-Regulation
chemical_list: D000900:Anti-Bacterial Agents; D002130:Calcium Phosphates; D002951:Citrates; D011500:Protein Synthesis Inhibitors; C485828:alpha-tricalcium phosphate; C485830:tetracalcium phosphate; C014148:phosphocitrate; C485838:calcium phosphate, monobasic, anhydrous; C020243:calcium phosphate; D003513:Cycloheximide; D017364:Collagenases; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13; D020784:Matrix Metalloproteinase 8; D020781:Matrix Metalloproteinase 1; C485829:calcium phosphate, dibasic, anhydrous; D004318:Doxycycline; D002131:Calcium Pyrophosphate