title: Possible protective effect of serum beta-carotene levels on the association between interleukin-1B C-31T polymorphism and hypertension in a Japanese population.
abstract: OBJECTIVE
  Recent studies have indicated a close relationship between hypertension and inflammation. Antioxidant substances, including beta-carotene, are known to be preventive factors for hypertension. We investigated the effect of serum beta-carotene levels on the association between the interleukin-1beta (IL-1B) C-31T polymorphism and hypertension.
  
  
  METHODS
  Subjects were 625 inhabitants (200 males and 425 females) of Japan, aged 39-70 years, who attended a health check-up examination in 2003. The IL-1B C-31T polymorphism was genotyped by polymerase chain reaction with confronting two-pair primers. Serum beta-carotene levels were measured using high-performance liquid chromatography.
  
  
  RESULTS
  The TT genotype of IL-1B C-31T was associated with an increased risk of hypertension in all subjects (Odds Ratio [OR]=1.82, 95% Confidence Interval [95% CI]=1.09-3.06, compared with CC genotype). Among male CC carriers, those with high serum beta-carotene levels had a significantly lower OR (OR=0.25, 95% CI=0.06-0.95) for hypertension relative to those with low serum beta-carotene levels. The TT carriers had a significantly higher OR compared with the CC carriers among males with high serum beta-carotene levels (OR=5.03, 95% CI=1.34-21.58) and among females with low serum beta-carotene levels (OR=2.47, 95% CI=1.04-6.00).
  
  
  CONCLUSIONS
  This study suggests that the IL-1B C-31T polymorphism is associated with hypertension, and that this association is modulated by serum beta-carotene levels.
authors.affiliation: Clinical Laboratory Medicine, Fujita Health University Graduate School of Health Research, 1-98 Dengakugakubo, Kutsukake-cho, Toyoake, Aichi 470-1192, Japan.
authors.forename: Atsumi
authors.initials: A
authors.lastname: Yanagisawa
authors.forename: Koji
authors.initials: K
authors.lastname: Suzuki
authors.forename: Asami
authors.initials: A
authors.lastname: Kimura
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ito
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Hamajima
authors.forename: Takashi
authors.initials: T
authors.lastname: Inoue
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001794:Blood Pressure / Q000235:genetics; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000235:genetics*; D053583:Interleukin-1beta / Q000235:genetics*; D007564:Japan; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000502:physiology*; D012307:Risk Factors; D017678:Sex Distribution; D014815:Vitamins / Q000097:blood*; D019207:beta Carotene / Q000097:blood*
chemical_list: D053583:Interleukin-1beta; D014815:Vitamins; D019207:beta Carotene