title: [Elevated serum dipeptidyl peptidase-4 activity in type 1 diabetes mellitus: a direct comparison].
abstract: Dipeptidyl peptidase-4 (DPP-4) has an important role in the carbohydrate metabolism with the degradation of incretin hormones.
  
  
  OBJECTIVE
  We assessed the serum DPP-4 activity both in fasting and postprandial condition in patients with type 1-, type 2 diabetes and healthy controls.
  
  
  METHODS
  Serum DPP-4 activities were determined at fasting sate and at 60 and 180 minutes after test meal. DPP-4 activity was measured by microplate-based kinetic assay in 41 type 1-, and in 87 type 2 diabetic patients and in 25 healthy volunteers.
  
  
  RESULTS
  Serum DPP-4 activities were found significantly higher both in fasting and postprandial state in patients with type 1 diabetes than in type 2 and control subjects. No change in the enzyme activities was found after test meal. Correlation was neither detected between the fasting plasma glucose nor between the HbA(1C) and the DPP-4 values in any of the groups studied.
  
  
  CONCLUSIONS
  RESULTS suggest that it is not the hyperglycemia, rather the type of diabetes which determinates the serum DPP-4 enzymatic activity. The exact background of this phenomenon is not yet clear, however, increased serum DPP-4 enzyme activity in type 1 diabetes mellitus may refer to pancreatic autoimmune process, concomitant autoimmune diseases, hormonal feed back mechanism, or even target organ damage.
authors.affiliation: Semmelweis Egyetem, Altalános Orvostudományi Kar II. Belgyógyászati Klinika Budapest Szentkirályi utca 46. 1088. timcsus@yahoo.com
authors.forename: Tímea
authors.initials: T
authors.lastname: Varga
authors.forename: Gábor
authors.initials: G
authors.lastname: Firneisz
authors.forename: Géza
authors.initials: G
authors.lastname: Nagy
authors.forename: Anikó
authors.initials: A
authors.lastname: Somogyi
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000201:enzymology*; D003924:Diabetes Mellitus, Type 2 / Q000201:enzymology; D018819:Dipeptidyl Peptidase 4 / Q000097:blood* / Q000378:metabolism; D005260:Female; D052216:Glucagon-Like Peptide 1 / Q000097:blood; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D018819:Dipeptidyl Peptidase 4; D052216:Glucagon-Like Peptide 1; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human; C042807:DPP4 protein, human