Dietary oxysterols are incorporated in plasma triglyceride rich lipoproteins, increase their susceptibility to oxidation and increase aortic cholesterol concentration of rabbits

  • Author(s) / Creator(s)
  • Early fatty streaks and advanced lesions are characterized by the deposition of cholesterol and cholesterol oxidation products (oxysterols). Oxysterols have been shown to be cytotoxic and pro-atherogenic compared to cholesterol and are found in cholesterol-rich processed foods. The consumption of dietary oxysterols may be significant in the onset and development of vascular disease. In order to study the short term effects of low levels of ingested dietary oxysterols on lipoprotein and aortic cholesterol and oxysterol levels, rabbits were fed either standard chow, chow supplemented with 1.0% oxidized cholesterol (containing 6% oxysterols), or 1.0% purified cholesterol (control). To determine the distribution and uptake of oxysterols after a 2-week dietar y period, triglyceride-rich plasma lipoproteins, low density lipoproteins and aorta were analyzed by GC–MS. The concentration of 7β-hydroxycholesterol was similar in all groups but the oxidized cholesterol-fed animals showed five times the concentration of 5α,6α-epoxycholesterol and double the level of 7-ketocholesterol in triglyceride-rich lipoproteins compared to the purified cholesterol-fed animals. The presence of 7-ketocholesterol in LDL was exclusive to animals fed the oxidized cholesterol diet. In addition, oxidation of triglyceride-rich lipoproteins was significantly greater in rabbits fed oxidized cholesterol compared to the pure cholesterol-fed animals. The oxidized cholesterol-fed animals also had a 64% increase in total aortic cholesterol, despite lower plasma cholesterol levels compared to the pure cholesterol control animals. Taken together these results suggest that dietary oxysterols may substantially increase the atherogenicity of lipoproteins.

  • Date created
    1998
  • Subjects / Keywords
  • Type of Item
    Article (Published)
  • DOI
    https://doi.org/10.7939/R3B27Q494
  • License
    © 1998 by Lipid Research, Inc.
  • Language
  • Citation for previous publication
    • Vine, D. F., Mamo, J. C. L., Beilin, L. J., Mori, T., & Croft, K. D. (1998). Dietary oxysterols are incorporated in plasma triglyceride rich lipoproteins, increase their susceptibility to oxidation and increase aortic cholesterol concentration of rabbits. Journal of Lipid Research, 39(10), 1995-2004. Retrieved from: http://www.jlr.org/content/39/10/1995.abstract
  • Link to related item
    http://www.jlr.org/content/39/10/1995.abstract