title: Effect of angiotensin-converting enzyme insertion/deletion genotype on collagen type I synthesis and degradation in patients with atrial fibrillation and arterial hypertension.
abstract: OBJECTIVE
  The present study was undertaken to assess the impact of the angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) polymorphisms on circulating markers of collagen type I synthesis and degradation, and also to study the effect of therapy with ACE inhibitors on these markers in hypertensive patients with atrial fibrillation (AF).
  
  
  METHODS
  ACE I/D genotypes were assessed in 158 hypertensive patients (71 +/- 9 years; 72 male) with AF and 174 patients with arterial hypertension in sinus rhythm (SR) (71 +/- 9 years; 88 male). Serum concentrations of amino-terminal propeptide of pro-collagen type I (PINP) and of carboxy-terminal telopeptide of collagen type I (CITP), indices of collagen type I synthesis and degradation, respectively, were measured.
  
  
  RESULTS
  Of the 332 study participants, 74 (22.3%) were I/I, 158 (47.6%) were I/D and 100 (30.1%) were D/D carriers. Genetic variation in ACE significantly influenced serum CITP levels in AF patients (p = 0.011). CITP levels were lower in D allele carriers (DD and ID) compared with I/I carriers. There was no difference in PINP levels between the different ACE genotype groups (p = 0.302). Patients treated with ACE inhibitors had higher CITP levels compared with those not treated (p = 0.036).
  
  
  CONCLUSIONS
  This study suggests that the presence of the D allele in hypertensive patients with AF is associated with attenuation of type-I collagen degradation, and that therapy with ACE inhibitors increases degradation of collagen type I. The data indicate a subgroup of patients with AF and arterial hypertension who may benefit to a greater extent from therapy with ACE inhibitors, thus, providing a basis for pharmacogenetics.
authors.affiliation: Democritus University of Thrace, University Cardiology Department, Voulgaroktonou 23, Alexandroupolis 68100, Greece. dtziakas@med.duth.gr
authors.forename: Dimitrios N
authors.initials: DN
authors.lastname: Tziakas
authors.forename: Georgios K
authors.initials: GK
authors.lastname: Chalikias
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Stakos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Papazoglou
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Papanas
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Papatheodorou
authors.forename: Sofia V
authors.initials: SV
authors.lastname: Chatzikyriakou
authors.forename: Stamatia
authors.initials: S
authors.lastname: Kotsiou
authors.forename: Efstratios
authors.initials: E
authors.lastname: Maltezos
authors.forename: Harisios
authors.initials: H
authors.lastname: Boudoulas
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000201:enzymology / Q000235:genetics*; D024042:Collagen Type I / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D004251:DNA Transposable Elements / Q000235:genetics; D005260:Female; D017353:Gene Deletion; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000201:enzymology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics
chemical_list: D024042:Collagen Type I; D004251:DNA Transposable Elements; D007703:Peptidyl-Dipeptidase A