SERUM PLANT STEROLS AND CHOLESTEROL PRECURSORS REFLECT CHOLESTEROL ABSORPTION AND SYNTHESIS IN VOLUNTEERS OF A RANDOMLY SELECTED MALE POPULATION

1990 ◽  
Vol 131 (1) ◽  
pp. 20-31 ◽  
Author(s):  
TATU A. MIETTINEN ◽  
REIJO S. TILVIS ◽  
Y. ANTERO KESÄNIEMI
Keyword(s):  
Cholesterol Absorption ◽  
Plant Sterols ◽  
Male Population ◽  
Cholesterol Precursors

scholarly journals Gas Chromatography–Tandem Mass Spectrometry Method for the Simultaneous Determination of Oxysterols, Plant Sterols, and Cholesterol Precursors

2012 ◽  
Vol 58 (11) ◽  
pp. 1557-1564 ◽  
Author(s):  
S Matysik ◽  
HH Klünemann ◽  
G Schmitz
Keyword(s):  
Gas Chromatography ◽  
Cholesterol Biosynthesis ◽  
Multiple Reaction Monitoring ◽  
Potassium Hydroxide Solution ◽  
Cholesterol Absorption ◽  
Plant Sterols ◽  
Plasma Samples ◽  
Fast Gas Chromatography ◽  
Positive Chemical Ionization ◽  
Cholesterol Precursors

BACKGROUND Cholesterol precursors and plant sterols have considerable potential as plasma biomarkers in several disorders of sterol metabolism and intestinal sterol absorption. Oxysterols are associated with atherogenesis, neurodegeneration, and inflammation. We developed a GC-MS method for the simultaneous analysis of these species in human plasma, including 24-, 25-, 27-hydroxycholesterol; 7-ketocholesterol; lanosterol; lathosterol; 7-dehydrocholesterol; desmosterol; stigmasterol; sitosterol; and campesterol. METHODS Sterols were hydrolyzed with ethanolic potassium hydroxide solution, extracted by liquid/liquid extraction with n-hexane, and derivatized with N-methyl-N-trimethylsilyl-trifluoracetamide. Positive chemical ionization with ammonia, as reagent gas, was applied to generate high abundant precursor ions. RESULTS The definition of highly sensitive precursor/product ion transitions, especially for coeluting substances, allowed fast gas chromatography run times of under 8.5 min. Using the multiple reaction monitoring mode, detection limits in the picogram per milliliter range could be achieved for most compounds. The method was validated for precision and recovery. Intraassay and interassay CVs were mostly <15% for serum and plasma samples. The recoveries of supplemented plasma samples in different concentrations were 88%–117%. The method was applied to stratification of patients with disorders in cholesterol biosynthesis and/or cholesterol absorption in hypercholesterolemia. The method revealed associations of sterol species with thyroid dysfunction and type 2 diabetes. CONCLUSIONS This method allows high-throughput sterol profiling in various diseases.

We-P14:471 Reduction of cholesterol absorption by dietary plant sterols and stanols in mice is independent from the ABCG5/ABCG8 transporter

2006 ◽  
Vol 7 (3) ◽  
pp. 450-451
Author(s):  
J.K. Kruit ◽  
T. Plösch ◽  
V.W. Bloks ◽  
N.C.A. Huijkman ◽  
R. Havinga ◽  
...  
Keyword(s):  
Cholesterol Absorption ◽  
Plant Sterols

Mechanisms of action of plant sterols on inhibition of cholesterol absorption

1991 ◽  
Vol 40 (S1) ◽  
pp. S59-S63 ◽  
Author(s):  
T. Heinemann ◽  
G. -A. Kullak-Ublick ◽  
B. Pietruck ◽  
K. von Bergmann
Keyword(s):  
Cholesterol Absorption ◽  
Mechanisms Of Action ◽  
Plant Sterols

Serum plant sterols and lathosterol related to cholesterol absorption in coeliac disease

1988 ◽  
Vol 174 (2) ◽  
pp. 213-224 ◽  
Author(s):  
M. Vuoristo ◽  
R. Tilvis ◽  
T.A. Miettinen
Keyword(s):  
Coeliac Disease ◽  
Cholesterol Absorption ◽  
Plant Sterols

Non-Nutritive Bioactive Constituents of Plants: Phytosterols

2003 ◽  
Vol 73 (2) ◽  
pp. 127-134 ◽  
Author(s):  
Miettinen ◽  
Gylling
Keyword(s):  
Serum Cholesterol ◽  
Cholesterol Absorption ◽  
Plant Sterols ◽  
Bioactive Constituents ◽  
Lower Serum ◽  
Cholesterol Levels ◽  
Lower Serum Cholesterol ◽  
Normal Human ◽  
Plant Stanol Esters

Normal human diet contains small amounts of phytosterols, mainly sitosterol and campesterol. Intestinal absorption of these plant sterols is low, about one tenth of that of cholesterol, such that their serum concentrations are also low, about 0.1 to 1% of the cholesterol levels. Like cholesterol they are transported by lipoproteins, mainly by LDL, and secreted unchanged in bile. Addition of plant sterols, or especially of their delta-5 saturated derivatives plant stanols into diet as fat-soluble esters inhibit cholesterol absorption and lower serum cholesterol similarly in short-term studies. Long-term consumption of plant stanol esters lowers serum cholesterol to the extent expected to reduce clinical manifestation of coronary heart disease by over 20% without detectable side effecs, cholesterol lowering being especially effective in combination with cholesterol synthesis inhibitors statins.

Molecular Insights into the Mechanisms Underlying the Cholesterol- Lowering Effects of Phytosterols

2019 ◽  
Vol 26 (37) ◽  
pp. 6704-6723 ◽  
Author(s):  
Lídia Cedó ◽  
Marta Farràs ◽  
Miriam Lee-Rueckert ◽  
Joan Carles Escolà-Gil
Keyword(s):  
Bile Acids ◽  
Molecular Mechanisms ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Cholesterol Absorption ◽  
Plant Sterols ◽  
Intestinal Lumen ◽  
Low Density ◽  
Intestinal Cholesterol Absorption ◽  
Cholesterol Lowering

Dietary phytosterols, which comprise plant sterols and stanols, reduce plasma Low-Density Lipoprotein-Cholesterol (LDL-C) levels when given 2 g/day. Since this dose has not been reported to cause health-related side effects in long-term human studies, food products containing these plant compounds are used as potential therapeutic dietary options to reduce LDL-C and cardiovascular disease risk. Several mechanisms have been proposed to explain the cholesterol-lowering action of phytosterols. They may compete with dietary and biliary cholesterol for micellar solubilization in the intestinal lumen, impairing intestinal cholesterol absorption. Recent evidence indicates that phytosterols may also regulate other pathways. Impaired intestinal cholesterol absorption is usually associated with reduced cholesterol transport to the liver, which may reduce the incorporation of cholesterol into Very-Low- Density Lipoprotein (VLDL) particles, thereby lowering the rate of VLDL assembly and secretion. Impaired liver VLDL production may reduce the rate of LDL production. On the other hand, significant evidence supports a role for plant sterols in the Transintestinal Cholesterol Excretion (TICE) pathway, although the exact mechanisms by which they promote the flow of cholesterol from the blood to enterocytes and the intestinal lumen remains unknown. Dietary phytosterols may also alter the conversion of bile acids into secondary bile acids, and may lower the bile acid hydrophobic/hydrophilic ratio, thereby reducing intestinal cholesterol absorption. This article reviews the progress to date in research on the molecular mechanisms underlying the cholesterol-lowering effects of phytosterols.

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