title: A lipidomics analysis of the relationship between dietary fatty acid composition and insulin sensitivity in young adults.
abstract: Relative to diets enriched in palmitic acid (PA), diets rich in oleic acid (OA) are associated with reduced risk of type 2 diabetes. To gain insight into mechanisms underlying these observations, we applied comprehensive lipidomic profiling to specimens collected from healthy adults enrolled in a randomized, crossover trial comparing a high-PA diet to a low-PA/high-OA (HOA) diet. Effects on insulin sensitivity (SI) and disposition index (DI) were assessed by intravenous glucose tolerance testing. In women, but not men, SI and DI were higher during HOA. The effect of HOA on SI correlated positively with physical fitness upon enrollment. Principal components analysis of either fasted or fed-state metabolites identified one factor affected by diet and heavily weighted by the PA/OA ratio of serum and muscle lipids. In women, this factor correlated inversely with SI in the fasted and fed states. Medium-chain acylcarnitines emerged as strong negative correlates of SI, and the HOA diet was accompanied by lower serum and muscle ceramide concentrations and reductions in molecular biomarkers of inflammatory and oxidative stress. This study provides evidence that the dietary PA/OA ratio impacts diabetes risk in women.
authors.affiliation: Department of Pediatrics, University of Vermont, Burlington, Vermont, USA. cl.kien@uvm.edu
authors.forename: C Lawrence
authors.initials: CL
authors.lastname: Kien
authors.forename: Janice Y
authors.initials: JY
authors.lastname: Bunn
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Poynter
authors.forename: Robert
authors.initials: R
authors.lastname: Stevens
authors.forename: James
authors.initials: J
authors.lastname: Bain
authors.forename: Olga
authors.initials: O
authors.lastname: Ikayeva
authors.forename: Naomi K
authors.initials: NK
authors.lastname: Fukagawa
authors.forename: Catherine M
authors.initials: CM
authors.lastname: Champagne
authors.forename: Karen I
authors.initials: KI
authors.lastname: Crain
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Koves
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Muoio
mesh_terms: D000293:Adolescent; D000328:Adult; D000375:Aging / Q000502:physiology; D001823:Body Composition; D015331:Cohort Studies; D018592:Cross-Over Studies; D004032:Diet / Q000009:adverse effects; D004041:Dietary Fats / Q000008:administration & dosage* / Q000145:classification / Q000378:metabolism; D005260:Female; D005504:Food Analysis; D006801:Humans; D007333:Insulin Resistance; D050356:Lipid Metabolism / Q000502:physiology*; D008297:Male; D009043:Motor Activity; D019301:Oleic Acid / Q000008:administration & dosage* / Q000737:chemistry; D019308:Palmitic Acid / Q000008:administration & dosage* / Q000737:chemistry; D010809:Physical Fitness; D012737:Sex Factors; D055815:Young Adult
chemical_list: D004041:Dietary Fats; D019301:Oleic Acid; D019308:Palmitic Acid