The Plasma Cholesterol: Cholesterol-Ester Cycle

  • S. Eisenberg
  • B. Perret
Conference paper

Abstract

Three years ago, at the V International Symposium on Atherosclerosis (l), we have presented evidence that both LDL and HDL are metabolic products of the core and surface domains of triglyceride-rich lipoproteins. The data can be summarized as follows: Triglyceride-rich lipoproteins (chylomicrons and VLDL) are primary secretory products of intestinal and hepatic cells. In the plasma, the two lipoproteins interact with lipoprotein lipases at luminal surfaces of endothelial cells and deliver triglyceride-fatty acids to tissues. The reaction leaves behind a triglyceride-depleted lipoprotein that contains non-hydrolyzable core lipids (cholesterol esters) and residual triglycerides. As well, the post-lipolysis particles remain with excess of surface constituents, phospholipids, free cholesterol and apoproteins. Our experiments indicated that the metabolism of non-triglyceride molecules in chylomicrons and VLDL is best described along two pathways: a core pathway, and a surface pathway (2, 3). Along the core pathway, the lipoprotein cholesterol ester and residual triglyceride molecules together with apo B and sufficient quantities of phospholipids and free cholesterol form remnant particles or LDL (4). Along the surface pathway, HDL precursors are formed (4, 5). These precursors are converted to spherical HDL by the activity of the LCAT system and accumulation of cholesterol ester molecules.

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References

  1. 1.
    Eisenberg S (1980) The origin in plasma of low density and high density lipoproteins. Atherosclerosis V: 146–151CrossRefGoogle Scholar
  2. 2.
    Eisenberg S (1980) Plasma lipoproteins interconversion. Ann NY Acad Sci 348: 30–47PubMedCrossRefGoogle Scholar
  3. 3.
    Eisenberg S, Chacjek T, Deekelbaum RJ (1981) The plasma origin of low density and high density lipoproteins. In: Parnow B, Carlson L (eds) Metabolie Risk Factors in Ischemic CV Disease, Raven Press, NY, pp 56–67Google Scholar
  4. 4.
    Deckelbaum RJ, Eisenberg S, Fainaru M, Barenholz Y, Olivecrona T (1979) In vitro production of human plasma very low density lipoprotein-like particles. A model for very low density lipoprotein catabolism. J Biol Chem 254:6079–6087PubMedGoogle Scholar
  5. 5.
    Chajek T, Eisenberg S (1978) Very low density lipoprotein. Metabolism of phospholipids, cholesterol, and apolipoprotein C in the isolated perfused rat heart. J Clin Invest 61: 1654–1665PubMedCrossRefGoogle Scholar
  6. 6.
    Perret BP, Eisenberg S, Chajek-Shaul T, Deckelbaum RJ, Olivecrona T (1982) Free cholesterol distribution during in vitro lipolysis of rat plasma very low density lipoprotein. Lack of a role for blood and heart cells. Submitted for publicationGoogle Scholar
  7. 7.
    Glomset JA, Norum KR (1973) The metabolic role of lecithin: cholesterol acyltransferase: Perspective from pathology. Adv Lipid Res 11: 1–65Google Scholar
  8. 8.
    Pattnaik NM, Montes A, Hughes LB, Zilversmit DB (1978) Cholesterol ester exchange protein in human plasma. Isolation and characterization. Biochim Biophys Acta 530: 428–438PubMedGoogle Scholar
  9. 9.
    Barter PJ, Lally JI (1978) The activity of an esterified cholesterol transferring factor in human and rat serum. Biochim Biophys Acta 531: 233–236PubMedGoogle Scholar
  10. 10.
    Nichols AV, Smith L (1965) Effect of very low density lipoprotein on lipid transfer in incubated plasma. J Lipid Res 6: 206–210PubMedGoogle Scholar
  11. 11.
    Nestel PK, Reardon M, Billington T (1979) In vivo transfer of cholesterol esters from high density lipoproteins to very low density lipoproteins in man. Biochim Biophys Acta 573: 403–407PubMedGoogle Scholar
  12. 12.
    Eisenberg S (1982) The plasma cholesterol ester transfer reaction. Evaluation of an experimental system and mechanism of transfer between high density (HDL) and very low density (VLDL) lipoproteins. Submitted for publicationGoogle Scholar
  13. 13.
    Deckelbaum R, Eisenberg S, Oschry Y, Olivecrona T (1982) Reverse modification of human plasma low density lipoprotein toward triglyceride rich precursors: A mechanism for losing excess cholesterol ester. J Biol Chem. In pressGoogle Scholar
  14. 14.
    Deckelbaum RJ, Eisenberg S, Oschry Y, Blum C (1981) Abnormal high density lipoproteins in abetalipoproteinemia. Relevance to normal HDL formation (Abstract) Arteriosclerosis 1:392Google Scholar
  15. 15.
    Oschry Y, Eisenberg S. Rat plasma lipoproteins. Re-evaluation of a lipoprotein system in an animal devoid of cholesterol ester transfer activity. J Lipid Res. In pressGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1983

Authors and Affiliations

  • S. Eisenberg
  • B. Perret

There are no affiliations available

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