title: Isolation of remnant particles by immunoseparation: a new approach for investigation of postprandial lipoprotein metabolism in normolipidemic subjects.
abstract: Abnormal postprandial lipoproteins are associated with an increased risk for cardiovascular disease. Postprandial remnant lipoproteins were usually analyzed indirectly using retinyl esters (RE) as a chylomicron core label during an oral fat loading test. Apo B-100 containing VLDL remnants in addition to apo B-48 containing chylomicron remnants can also be directly quantified using the RLP-Cholesterol Immunoseparation Assay. This recently available method uses monoclonal antibodies to apo A-I and apo B-100 to remove non-remnant lipoproteins and quantifies cholesterol in the remaining apo E-rich remnant fraction. In the present study we compared the analysis of retinyl ester with the immuno-based RLP-Cholesterol (RLP-C) analysis in measuring postprandial remnant lipoproteins in healthy normolipidemic subjects. Sixteen healthy normolipidemic subjects were selected for this study. Postprandial plasma retinyl esters peaked at 5.0+/-1.2 h, whereas plasma RLP-C showed a peak significantly earlier (P<0.001) at 3.5+/-0.6 h. In comparison, postprandial plasma TG and FFA peaked at 3.3+/-1.1 h (P<0.005 compared to retinyl esters). In conclusion, levels of RLP-C changed, during the postprandial phase, in parallel with plasma TG and FFA concentrations and peaked significantly earlier than retinyl esters. Postprandial measurements of RLP-C can be considered as a fast alternative method for the more laborious retinyl-ester analysis in clinical studies.
authors: Department of Internal Medicine, G02.228, University Medical Center Utrecht, PO Box 85500, 3508 GA Utrecht, The Netherlands.
authors: P C
authors: PC
authors: Schreuder
authors: T B
authors: TB
authors: Twickler
authors: T
authors: T
authors: Wang
authors: K
authors: K
authors: Nakajima
authors: D W
authors: DW
authors: Erkelens
authors: G M
authors: GM
authors: Dallinga-Thie
mesh_terms: D000328:Adult; D001053:Apolipoproteins / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism*; D002784:Cholesterol; D006801:Humans; D007163:Immunosorbent Techniques; D008074:Lipoproteins / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism*; D008875:Middle Aged; D019518:Postprandial Period; D014280:Triglycerides / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D001053:Apolipoproteins; D008074:Lipoproteins; D014280:Triglycerides; C112017:remnant-like particle cholesterol; D002784:Cholesterol