title: Gelatinolytic and collagenolytic activity in periprosthetic tissues from loose hip endoprostheses.
abstract: OBJECTIVE
  To study the contribution of different members of the metalloproteinases (MMP) family in gelatinolytic and collagenolytic potential, namely dinitrophenyl-Pro-Gln-Gly-Ile-Ala-Gly-Gln-D-Arg (DNP-S) sensitive proteolytic activity, in loose total hip arthroplasty (THA) endoprostheses.
  
  
  METHODS
  Periprosthetic tissues and fluid samples were collected from patients subjected to hip endoprosthesis replacement. DNP-S sensitive proteolytic activity was evaluated by the degradation of synthetic DNP-S and reverse phase high performance liquid chromatography, while gelatinolytic activity was assessed by gelatin zymography. The isolation and separation of gelatinases was performed by gelatin- and concanavalin A-Sepharose affinity chromatographies and the identification of collagenases by immunoblot analysis.
  
  
  RESULTS
  High gelatinolytic activity was observed in all periprosthetic tissue extracts and fluid samples. All samples also exhibited DNP-S degrading activity, without pretreatment by activating agents. Upon fractionation of MMP by gelatin-Sepharose affinity chromatography it was found that the gelatin-unbound collagenases are exclusively responsible for DNP-S degrading activity. Activated species of both MMP-1 and 13 were detected in most samples, but not the soluble form of MT1-MMP. Separation of gelatinases from each other and treatment with 4-aminophenylmercuric acetate (APMA) revealed that both enzymes mainly existed in complex with tissue inhibitor of metalloproteinase (TIMP).
  
  
  CONCLUSIONS
  MMP-1 and MMP-13, which exist in activated form, could be responsible for the DNP-S-degrading activity in periprosthetic tissues and fluids, while the gelatinases do not contribute in this potential, since they mainly exist in complex with TIMP. The 2 collagenases may play a key role in the loosening of THA endoprostheses.
authors.affiliation: Laboratory of Biochemistry, Department of Chemistry, and Departments of Orthopaedics and Pharmacology, School of Medicine, University of Patras, Patras, Greece.
authors.forename: S A
authors.initials: SA
authors.lastname: Syggelos
authors.forename: S C
authors.initials: SC
authors.lastname: Eleftheriou
authors.forename: E
authors.initials: E
authors.lastname: Giannopoulou
authors.forename: E
authors.initials: E
authors.lastname: Panagiotopoulos
authors.forename: A J
authors.initials: AJ
authors.lastname: Aletras
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D001826:Body Fluids / Q000201:enzymology; D003094:Collagen / Q000378:metabolism*; D017364:Collagenases / Q000378:metabolism*; D004136:Dinitrobenzenes / Q000378:metabolism; D004792:Enzyme Precursors / Q000378:metabolism; D005260:Female; D005780:Gelatin / Q000378:metabolism; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism*; D053509:Matrix Metalloproteinase 13; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9; D008875:Middle Aged; D011475:Prosthesis Failure; D014020:Tissue Extracts / Q000378:metabolism; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism
chemical_list: D004136:Dinitrobenzenes; D004792:Enzyme Precursors; D014020:Tissue Extracts; D019715:Tissue Inhibitor of Metalloproteinase-1; D005780:Gelatin; D003094:Collagen; D017364:Collagenases; C507079:MMP13 protein, human; D053509:Matrix Metalloproteinase 13; C120487:pro-matrix metalloproteinase 9; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020781:Matrix Metalloproteinase 1