title: Vitamin A supplementation and serum Th1- and Th2-associated cytokine response in women.
abstract: OBJECTIVE
  T helper (Th)1/Th2 immune response has been linked to obesity-related immune disorders. It has been proven that retinoid active derivates improve immunity via regulating Th1/Th2 balance. However, there is not a well-identified report of direct effect of vitamin A on Th1/Th2 balance in obesity. The present study aimed to investigate the possible role of vitamin A on serum Th1/Th2 response in obese women.
  
  
  METHODS
  A randomized double-blind placebo-controlled trial was conducted on 84 obese (n = 56; body mass index [BMI] 30-39.9 kg/m(2)) and nonobese (n = 28; BMI 18.5-24.9 kg/m(2)) women. Obese women were randomly allocated to receive either vitamin A (retinyl palmitate 25,000 IU/d) or placebo. Nonobese women also received 25,000 IU/d retinyl palmitate. Anthropometric variables were assessed and serum interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-4, and IL-13 were analyzed before and 4 months after intervention.
  
  
  RESULTS
  Vitamin A treatment significantly reduced serum concentrations of IL-1β in obese vitamin A-treated subjects (from 3.58 ± 0.36 to 2.45 ± 0.23 pg/ml, p < 0.006). Serum concentrations of IL-4 and IL-13 were also reduced in obese and nonobese vitamin A-treated subjects (p < 0.05). A significant reduction in IL-1β/IL-4 ratio in the obese vitamin A-treated group was also observed (p = 0.03).
  
  
  CONCLUSIONS
  Decline in serum concentrations of IL-1β and IL-1β/IL-4 ratio in obese women suggests that vitamin A is capable of regulating the immune system and possibly reducing the risk of autoimmune disease in this group. Further studies are needed to explore the possible underlying mechanisms.
authors.affiliation: a Department of Community Nutrition.
authors.forename: Mahdieh Abbasalizad
authors.initials: MA
authors.lastname: Farhangi
authors.forename: Seyyed Ali
authors.initials: SA
authors.lastname: Keshavarz
authors.forename: Mohammadreza
authors.initials: M
authors.lastname: Eshraghian
authors.forename: Alireza
authors.initials: A
authors.lastname: Ostadrahimi
authors.forename: Ali-Akbar
authors.initials: AA
authors.lastname: Saboor-Yaraghi
mesh_terms: D000328:Adult; D015992:Body Mass Index; D016207:Cytokines / Q000097:blood*; D019587:Dietary Supplements; D004224:Diterpenes; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D018793:Interleukin-13 / Q000097:blood; D053583:Interleukin-1beta / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D009765:Obesity / Q000097:blood* / Q000276:immunology; D000084562:Retinyl Esters; D058408:Th1-Th2 Balance / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D014801:Vitamin A / Q000008:administration & dosage / Q000031:analogs & derivatives*
chemical_list: D016207:Cytokines; D004224:Diterpenes; D018793:Interleukin-13; D053583:Interleukin-1beta; D000084562:Retinyl Esters; D014409:Tumor Necrosis Factor-alpha; D014801:Vitamin A; C014794:retinol palmitate; D015847:Interleukin-4