title: Associations between plasma polyunsaturated fatty acids, plasma stearoyl-CoA desaturase indices and body fat.
abstract: OBJECTIVE
  Stearoyl-CoA desaturase (SCD)-1 deficient mice are resistant to obesity and plasma SCD indices are related to obesity in humans. Both n-3 and n-6 polyunsaturated fatty acids (PUFA) regulate expression of the SCD enzymes. Whether higher plasma PUFA were associated with lower SCD indices in humans was examined.
  
  
  METHODS
  Population-based study of 2,021 elderly subjects from the Hordaland Health Study. Using multivariate linear regression, the cross-sectional associations among plasma PUFA, estimated SCD indices (from fatty acid profiles in plasma total lipids), and fat mass measured by dual-energy X-ray absorptiometry were explored. Two plasma SCD indices were used: SCD-16 (16:1n-7/16:0) and SCD-18 (18:1n-9/18:0).
  
  
  RESULTS
  Plasma total, n-6 and n-3 PUFA were inversely associated with both SCD indices (P < 0.001 for all). Among the individual PUFA, 18:2n-6 showed the strongest association with SCD-16 (partial r = -0.59, P < 0.001) followed by 20:5n-3 (partial r = -0.13; P < 0.001). Plasma total, n-6 and n-3 PUFA were inversely associated with body fat (P < 0.001 for all); the associations were markedly attenuated following adjustment for SCD-16.
  
  
  CONCLUSIONS
  The epidemiological data are in line with animal studies and suggest that PUFA may decrease SCD1 activity in humans, with possible reduction in body fat.
authors.affiliation: Department of Nutrition, Institute of Basic Medical Science, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: Kathrine J
authors.initials: KJ
authors.lastname: Vinknes
authors.forename: Amany K
authors.initials: AK
authors.lastname: Elshorbagy
authors.forename: Christian A
authors.initials: CA
authors.lastname: Drevon
authors.forename: Eha
authors.initials: E
authors.lastname: Nurk
authors.forename: Grethe S
authors.initials: GS
authors.lastname: Tell
authors.forename: Ottar
authors.initials: O
authors.lastname: Nygård
authors.forename: Stein E
authors.initials: SE
authors.lastname: Vollset
authors.forename: Helga
authors.initials: H
authors.lastname: Refsum
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D044943:Fatty Acid Desaturases / Q000097:blood; D015525:Fatty Acids, Omega-3 / Q000097:blood* / Q000378:metabolism / Q000494:pharmacology; D043371:Fatty Acids, Omega-6 / Q000097:blood* / Q000378:metabolism / Q000494:pharmacology; D005260:Female; D006801:Humans; D008297:Male; D009765:Obesity / Q000097:blood / Q000201:enzymology / Q000378:metabolism*; D013230:Stearoyl-CoA Desaturase / Q000097:blood*
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase