Detection of remnant proteolytic activities in unimplanted glutaraldehyde-treated bovine pericardium and explanted cardiac bioprostheses

J Biomed Mater Res. 1993 Jun;27(6):821-9. doi: 10.1002/jbm.820270615.


The presence and activity of proteolytic enzymes has been investigated in vitro on soluble and insoluble preparations obtained from both unimplanted and implanted glutaraldehyde-treated bovine parietal pericardium. Using detection by colorimetric techniques, soluble preparations were shown to hydrolyze enzyme substrates that are characteristic for trypsin-like proteases, cathepsin-like proteases, and collagenase. As detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis in gradient gels and gel filtration on Sepharose CL-6B, insoluble (pellet) preparations degraded denatured type I collagen in a time-dependent pattern, producing low-molecular-weight fragments. These activities were partially inhibited by phenylmethylsulfonyl fluoride, N-ethyl maleimide, soybean trypsin inhibitor, para-chloromercuribenzoic acid, or ethylenediaminetetraacetic acid, suggesting the presence of a heterogeneous enzymatic mixture. Insoluble preparations incubated with pure pericardial dermatan sulfate proteoglycan detached the glycosaminoglycan chains from their core protein carrier, producing a digestion pattern similar to Cathepsin C. These findings demonstrate the presence of active proteases in glutaraldehyde-fixed bovine pericardium per se and in explanted pericardial bioprosthetic cardiac valves, an additional factor that might contribute to intrinsic extracellular matrix degeneration in pericardial bioprosthetic devices.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Bioprosthesis*
  • Cattle
  • Chromatography, Gel
  • Collagen / metabolism
  • Colorimetry
  • Electrophoresis, Polyacrylamide Gel
  • Glutaral / pharmacology*
  • Heart Valve Prosthesis*
  • Molecular Sequence Data
  • Peptide Hydrolases / analysis*
  • Pericardium / drug effects
  • Pericardium / enzymology*
  • Protease Inhibitors / pharmacology
  • Proteoglycans / metabolism
  • Serum Albumin / metabolism


  • Protease Inhibitors
  • Proteoglycans
  • Serum Albumin
  • Collagen
  • Peptide Hydrolases
  • Glutaral