title: Trypsin, elastase, plasmin and MMP-9 activity in the serum during the human ageing process.
abstract: OBJECTIVE
  the aim of this work was to define the influence of the ageing process on the activity of proteolytic enzymes, such as trypsin, elastase, plasmin and active MMP-9 concentration, as well as the inhibitor alpha 1-antitrypsin. Moreover, we assessed associations between enzyme activity and selected clinical and biochemical parameters.
  
  
  METHODS
  healthy normotensive volunteers (n = 60, 30 women) aged 20-82 years were split into subgroups: young (aged 20-22), middle-aged (49-52) and elderly (77-82). Serum enzyme activity was assessed using fluorometric methods.
  
  
  RESULTS
  overall, active MMP-9 concentration and trypsin activity decreased with age, and alpha1-antitrypsin concentration and plasmin activity increased. Activity of elastase increased with age when compared to the young age group. An inverse correlation was identified between MMP-9 concentration and BMI and a direct correlation found between BMI and elastase, plasmin activity and alpha1-antitrypsin concentration. In the middle-aged group, glucose correlated directly with trypsin activity and inversely with MMP-9 concentration. Trypsin activity and MMP-9 concentration correlated inversely with cholesterol concentration and plasmin and elastase activity, and the alpha1-antitrypsin concentration correlated with cholesterol concentration in the overall group.
  
  
  CONCLUSIONS
  the results confirm the influence of the ageing process on the activity of serum proteolytic enzymes. The activity of individual proteolytic enzymes in the serum changes with age.
authors.affiliation: Department of Immunology, Transplantology and Internal Diseases, Medical University of Warsaw, 02-006 Warsaw, Nowogrodzka 59, Poland. leszekpaczek@onet.pl
authors.forename: Leszek
authors.initials: L
authors.lastname: Paczek
authors.forename: Wanda
authors.initials: W
authors.lastname: Michalska
authors.forename: Irena
authors.initials: I
authors.lastname: Bartlomiejczyk
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000097:blood*; D002784:Cholesterol / Q000097:blood; D005260:Female; D005341:Fibrinolysin / Q000378:metabolism*; D005470:Fluorometry; D006801:Humans; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D009994:Osmolar Concentration; D010196:Pancreatic Elastase / Q000097:blood*; D015842:Serine Proteinase Inhibitors / Q000097:blood; D014357:Trypsin / Q000097:blood*; D000515:alpha 1-Antitrypsin / Q000097:blood
chemical_list: D015842:Serine Proteinase Inhibitors; D000515:alpha 1-Antitrypsin; D002784:Cholesterol; D010196:Pancreatic Elastase; D014357:Trypsin; D005341:Fibrinolysin; D020780:Matrix Metalloproteinase 9