title: Estimated plasma stearoyl co-A desaturase-1 activity and risk of incident diabetes: the Atherosclerosis Risk in Communities (ARIC) study.
abstract: OBJECTIVE
  Evidence from pre-clinical studies suggests inhibition of stearoyl co-A desaturase-1 (SCD-1) activity improves insulin sensitivity. Translation of these findings to humans remains less defined. The purpose of this research was to evaluate the association between different measures of SCD-1 activity and incident diabetes in a large, prospective human study.
  
  
  METHODS
  In 2738 white participants (aged 45-64 yrs, 47% men) who were free of diabetes at baseline, SCD-1 activity was estimated at baseline by plasma fatty acid ratios in cholesterol esters (SCD16c=16:1n-7/16:0, SCD18c =18:1n-9/18:0) and in phospholipids (SCD16p=16:1n-7/16:0, SCD18p=18:1n-9/18:0). Incident diabetes was ascertained during 3 follow-up visits. Cox proportional hazards regression was used to determine the association between estimated SCD-1 activity and incident diabetes.
  
  
  RESULTS
  During follow-up (mean 8.0±SE 2.1 years), 207 (7.6%) participants developed diabetes. After adjusting for age and sex, higher SCD16c, higher SCD16p, and lower SCD18p were significantly associated with incident diabetes. After additional adjustment for education, parental history of diabetes, smoking, dietary intake (carbohydrate, fiber, saturated/monounsaturated/polyunsaturated fat), alcohol use, physical activity, body mass index (BMI), waist-hip ratio, blood pressure, and lipid composition - only SCD16c remained significantly associated with incident diabetes (Hazard Ratio=1.1 linearly across decreasing quintiles, 95% CI 1.01-1.30; p =0.03) which remained nominally associated after adjusting for insulin resistance (p=0.05).
  
  
  CONCLUSIONS
  In a large community-based prospective cohort study, the estimate of SCD-1 activity by SCD16c had the strongest association with incident diabetes. Refinement of SCD-1 measurement and replication of its association with incident diabetes in an independent cohort is recommended.
authors: Department of Medicine, University of Minnesota, Minneapolis, MN, USA. chow0007@umn.edu
authors: Lisa S
authors: LS
authors: Chow
authors: Shuzhen
authors: S
authors: Li
authors: Lynn E
authors: LE
authors: Eberly
authors: Elizabeth R
authors: ER
authors: Seaquist
authors: John H
authors: JH
authors: Eckfeldt
authors: Ron C
authors: RC
authors: Hoogeveen
authors: David J
authors: DJ
authors: Couper
authors: Lyn M
authors: LM
authors: Steffen
authors: James S
authors: JS
authors: Pankow
mesh_terms: D002788:Cholesterol Esters / Q000097:blood; D015331:Cohort Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000201:enzymology* / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D013230:Stearoyl-CoA Desaturase / Q000097:blood*; D014481:United States / Q000453:epidemiology
chemical_list: D002788:Cholesterol Esters; C523776:SCD1 protein, human; D013230:Stearoyl-CoA Desaturase