title: The imbalance of cathepsin B-like activity in acromegalic patients--preliminary report.
abstract: OBJECTIVE
  Acromegaly is a rare disease due to growth hormone (GH) excess. Patients must be carefully follow up because of mortality and co-morbidity increased risks. Since routinely used GH and insulin-like growth factor-1(IGF-1) estimations are not always sufficient, patients require assessment of organ- or tissue-specific tests. Cysteine proteases (CP), including cathepsin B, have been tested in a number of pathologies in respect of a role in pathogenesis and potential utility in the disease activity and prognosis assessment. There is lack of data on CP activity in acromegaly.
  
  
  METHODS
  In present study cathepsin B-like and cysteine peptidase inhibitor (CPI) activities have been tested in 29 acromegaly patients and in 15 healthy controls. Cathepsin B activity was assayed with N-bansoyl-DL-arginine-beta-naphthylamide (BANA) as substrate by the Barrett method. CPI activity was determined by measuring the inhibition of papain.
  
  
  RESULTS
  Serum cathepsin B activity (median: 1.38 U/ml) and CPI activity (median: 93.08 U/ml) were higher in acromegaly then in controls (0.93 U/ml and 82.55 U/ml, p=0.000017 and 0.00285, respectively). Neither cathepsin B nor CPI activity was correlated with GH or IGF-1 level. No correlation was recorded between cathepsin B and CPI activity.
  
  
  CONCLUSIONS
  It was shown for the first time that cathepsin B and CPI activities are increased in acromegaly. These findings suggest to study cathepsin system as an adjuvant parameter in the assessment of the overall acromegaly complications. Moreover, CP may be involved in pathomechanism of organ complications in acromegaly and may interfere with IGF-1 action.
authors.affiliation: Department of Endocrinology, Diabetology and Isotope Therapy, Medical University Wroclaw, Poland. daro48@o2.pl
authors.forename: Jacek
authors.initials: J
authors.lastname: Daroszewski
authors.forename: Marek
authors.initials: M
authors.lastname: Bolanowski
authors.forename: Marcin
authors.initials: M
authors.lastname: Kaluzny
authors.forename: Maciej
authors.initials: M
authors.lastname: Siewinski
mesh_terms: D000172:Acromegaly / Q000097:blood*; D000328:Adult; D002401:Cathepsin B / Q000097:blood*; D015853:Cysteine Proteinase Inhibitors / Q000097:blood*; D005260:Female; D019382:Human Growth Hormone / Q000097:blood; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D008297:Male; D008875:Middle Aged
chemical_list: D015853:Cysteine Proteinase Inhibitors; D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I; D002401:Cathepsin B