title: Genetic polymorphisms of angiotensin-I converting enzyme, haptoglobin and angiotensinogen and oxidative stress parameters in 12 to 15-year-old adolescents.
abstract: BACKGROUND
  Angiotensin-converting enzyme (ACE) I/D, haptoglobin (Hp) 1/2 and angiotensinogen (AGT) M235T gene polymorphisms have been associated with the risk of various cardiovascular conditions. Oxidative stress and reactive oxygen species have also been implicated in endothelial injury. In a randomly selected sample of healthy adolescents, we studied the relationship between these genetic polymorphisms and somatic characteristics, blood pressure and certain biochemical markers of oxidative stress.
  
  
  METHODS
  A sample of 49 healthy adolescents were genotyped for ACE I/D, Hp 1/2 and AGT M235T polymorphisms. Anthropometric parameters, blood pressure and lipid profile were evaluated using internationally recommended methods. Serum ACE activity and oxidative stress markers were determined either by spectrophotometric methods or with commercially available kits.
  
  
  RESULTS
  Males had higher values for ACE activity than females (p < 0.01). The haptoglobin Hp allele 1 and the ACE D allele were associated with higher ACE activity (p < 0.05 and p < 0.001). ACE activity was similar between AGT genotypes. Higher levels of MDA-LDL/Apo B were observed in individuals with both ACE DD and Hp 2-2 genotypes. Carriers of the AGT TT genotype showed higher diastolic blood pressures than other AGT genotypes.
  
  
  CONCLUSIONS
  Carriers of both ACE DD and Hp 2-2 genotypes have a higher pro-oxidant status and AGT TT carriers have higher diastolic blood pressures, which may indicate a higher risk for development of hypertension in these individuals.
authors.affiliation: Laboratório de Genética, Faculdade de Medicina de Lisboa, Lisboa, Portugal.
authors.forename: Constança
authors.initials: C
authors.lastname: Coelho
authors.forename: Antonio
authors.initials: A
authors.lastname: Guerra
authors.forename: Carla
authors.initials: C
authors.lastname: Rego
authors.forename: Luíza
authors.initials: L
authors.lastname: Breitenfeld
authors.forename: Elisabete
authors.initials: E
authors.lastname: Castro
authors.forename: Paulino
authors.initials: P
authors.lastname: Rodrigues
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Laires
authors.forename: Manuel
authors.initials: M
authors.lastname: Bicho
mesh_terms: D000293:Adolescent; D000808:Angiotensinogen / Q000235:genetics*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006242:Haptoglobins / Q000235:genetics*; D006801:Humans; D008297:Male; D018384:Oxidative Stress / Q000235:genetics*; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D006242:Haptoglobins; D000808:Angiotensinogen; D007703:Peptidyl-Dipeptidase A