title: Determinants of insulin responsiveness in young women: Impact of polycystic ovarian syndrome, nitric oxide, and vitamin D.
abstract: BACKGROUND
  Polycystic ovary syndrome (PCOS) is associated with incremental risk of atherosclerosis and possibly of cardiovascular events. Insulin resistance (IR) occurs frequently in PCOS subjects, which might be one of the mechanisms involved in engendering such risk. We sought to evaluate whether the impact of other factors potentially associated both with PCOS and with IR might differentially modulate degree of IR in women with and without PCOS.
  
  
  RESULTS
  We measured body mass index (BMI), hs-CRP, plasma concentrations of asymmetric dimethylarginine (ADMA), vitamin D (25(OH)D3) levels and platelet responsiveness to nitric oxide donor sodium nitroprusside (NO responsiveness) in 47 young women (n=27 with PCOS and n=20 weight-matched controls) without metabolic syndrome, hypertension or overt cardiovascular disease. We performed univariate and multivariate regression analyses to establish correlates of the quantitative insulin-sensitivity check index (QUICKI), as a marker of IR. On univariate analysis, plasma 25(OH)D3 levels and low NO responsiveness tended to be direct correlates with QUICKI in the entire subject group. BMI, hs-CRP, and ADMA levels were significant inverse correlates of QUICKI in PCOS subjects, but not in subjects without PCOS. On multivariate analysis, NO responsiveness, and 25(OH)D3 levels, but not PCOS per se were significant correlates of QUICKI.
  
  
  CONCLUSIONS
  In the entire cohort of young women, low NO responsiveness and vitamin D deficiency are associated with low QUICKI, while elevated ADMA, inflammatory activation and obesity are selectively associated with low QUICKI in PCOS subjects; this may contribute to the increased cardiovascular risk associated with this syndrome.
authors: Vascular Disease and Therapeutics Research Group, Basil Hetzel Institute, The Queen Elizabeth Hospital, Department of Medicine, The University of Adelaide, Australia.
authors: D T M
authors: DT
authors: Ngo
authors: W P
authors: WP
authors: Chan
authors: S
authors: S
authors: Rajendran
authors: T
authors: T
authors: Heresztyn
authors: A
authors: A
authors: Amarasekera
authors: A L
authors: AL
authors: Sverdlov
authors: P D
authors: PD
authors: O'Loughlin
authors: H A
authors: HA
authors: Morris
authors: Y Y
authors: YY
authors: Chirkov
authors: R J
authors: RJ
authors: Norman
authors: J D
authors: JD
authors: Horowitz
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D007333:Insulin Resistance; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D011085:Polycystic Ovary Syndrome / Q000378:metabolism*; D014807:Vitamin D / Q000378:metabolism*; D055815:Young Adult
chemical_list: D007328:Insulin; D014807:Vitamin D; D009569:Nitric Oxide