Improved cholesterol phenotype analysis by a model describing how lipoprotein lifecycle processes depend on particle size

Increased plasma cholesterol is a known risk factor for cardiovascular disease. Lipoprotein particles transport both cholesterol and triglycerides through the blood. It is thought that the size distribution of these particles codetermines cardiovascular disease risk. New types of measurements can determine the concentration of many lipoprotein size-classes but exactly how each small class relates to disease risk is difficult to clear up. Because relating physiological process status to disease risk seems promising, we propose investigating how lipoprotein production, lipolysis, and uptake processes depend on particle size. To do this, we introduced a novel model framework (Particle Profiler) and evaluated its feasibility. The framework was tested using existing stable isotope flux data. The model framework implementation we present here reproduced the flux data and derived lipoprotein size pattern changes that corresponded to measured changes. It also sensitively indicated changes in lipoprotein metabolism between patient groups that are biologically plausible. Finally, the model was able to reproduce the cholesterol and triglyceride phenotype of known genetic diseases like familial hypercholesterolemia and familial hyperchylomicronemia. In the future, Particle Profiler can be applied for analyzing detailed lipoprotein size profile data and deriving rates of various lipolysis and uptake processes if an independent production estimate is given.
Authors: 
D.B. van Schalkwijk, A.A. de Graaf, B. van Ommen, K. van Bochove, P.C.N. Rensen, L.M. Havekes, N.C.A. van de Pas, H.C.J. Hoefsloot, J. van der Greef, A.P. Freidig
Publication data (text): 
2009
DOI: 
10.1194/jlr.M800354-JLR200
Pages: 
2009; 50 (12): 2398-2411
Published in: 
Journal of Lipid Research
Date of publication: 
December, 2009
Status of the publication: 
Published/accepted