title: Changes in low-density lipoprotein size phenotypes associate with changes in apolipoprotein C-III glycoforms after dietary interventions.
abstract: The presence of small dense low-density lipoprotein (LDL) is associated with obesity, type II diabetes, and an increased risk for cardiovascular disease. Apolipoprotein C-III (apoC-III) is involved in the formation of small dense LDL, but the exact mechanisms are still not well defined. ApoC-III is a glycosylated apolipoprotein, with 3 major glycoforms: apoC-III0, apoC-III1, and apoC-III2that contain 0, 1, or 2 molecules of sialic acid, respectively. In our previous work, we reported an association among apoC-III0and apoC-III1, but not apoC-III2with fasting plasma triglyceride levels in obesity and type II diabetes.
  
  
  
  The goal of this study was to determine the relationship between changes in the major apoC-III glycoforms and small dense LDL levels after dietary interventions.
  
  
  
  Mass spectrometric immunoassay was performed on fasting plasma samples from 61 subjects who underwent either a high-carbohydrate diet (n = 34) or a weight loss intervention (n = 27).
  
  
  
  After both dietary interventions, changes in total apoC-III concentrations were associated with changes in LDL peak particle diameter (r = -0.58, P < .0001). Increases in total apoC-III concentrations after the high-carbohydrate diet were associated with decreases in LDL size (r = -0.53, P = .001), and decreases in apoC-III concentrations after weight loss were associated with increases in LDL peak particle diameter (r = -0.54, P = .004). Changes in concentrations of apoC-III1and apoC-III0, but not apoC-III2, were associated with changes in LDL peak particle diameter in both the weight loss and high-carbohydrate interventions.
  
  
  
  We conclude that apoC-III0and apoC-III1, but not apoC-III2are associated with the formation of small dense LDL.
authors.affiliation: Department of Medicine, University of Southern California, Los Angeles, CA, USA.
authors.forename: Saulo
authors.initials: S
authors.lastname: Mendoza
authors.affiliation: Molecular Biomarkers Laboratory, The Biodesign Institute, Arizona State University, Tempe, AZ, USA.
authors.forename: Olgica
authors.initials: O
authors.lastname: Trenchevska
authors.affiliation: Atherosclerosis Research, Children's Hospital Oakland Research Institute, Oakland, CA, USA.
authors.forename: Sarah M
authors.initials: SM
authors.lastname: King
authors.affiliation: Molecular Biomarkers Laboratory, The Biodesign Institute, Arizona State University, Tempe, AZ, USA.
authors.forename: Randall W
authors.initials: RW
authors.lastname: Nelson
authors.affiliation: Molecular Biomarkers Laboratory, The Biodesign Institute, Arizona State University, Tempe, AZ, USA.
authors.forename: Dobrin
authors.initials: D
authors.lastname: Nedelkov
authors.affiliation: Atherosclerosis Research, Children's Hospital Oakland Research Institute, Oakland, CA, USA.
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Krauss
authors.affiliation: Department of Medicine, University of Southern California, Los Angeles, CA, USA. Electronic address: hyassine@usc.edu.
authors.forename: Hussein N
authors.initials: HN
authors.lastname: Yassine
mesh_terms: D053305:Apolipoprotein C-III / Q000097:blood*; D004032:Diet; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood* / Q000737:chemistry*; D008297:Male; D008875:Middle Aged; D010316:Particle Size; D010641:Phenotype; D015431:Weight Loss / Q000187:drug effects
chemical_list: D053305:Apolipoprotein C-III; D004040:Dietary Carbohydrates; D008077:Lipoproteins, LDL
keywords: Apolipoprotein C-III; Low-density lipoprotein; Mass spectrometry; Metabolism; Sialylation