In general , markers for cholesterol absorption and synthesis displayed reciprocal patterns , showing that cholesterol metabolism is tightly regulated by the interplay of intestinal absorption and endogenous synthesis .
Distinctive patterns for cholesterol absorption or cholesterol synthesis could be identified , suggesting that metabolic disorders can be classified as ' cholesterol absorbers or cholesterol synthesizers ' .
Non-cholesterol sterols are vali date d biomarkers for intestinal cholesterol absorption and endogenous cholesterol synthesis .
However , their use in metabolic disturbances has not been systematic ally explored .
Therefore , we conducted a systematic review to provide an overview of non-cholesterol sterols as markers for cholesterol metabolism in different metabolic disorders .
Deuterium uptake and plasma cholesterol precursor levels correspond as methods for measurement of endogenous cholesterol synthesis in hypercholesterolemic women
To assess the validity of two techniques used to measure human cholesterol synthesis , the rate of uptake of deuterium ( D ) into plasma free cholesterol ( FC ) , and plasma cholesterol precursor ( squalene , lanosterol , desmosterol and lathosterol ) levels were compared in 14 women [ 65–71 yr with low density lipoprotein-cholesterol (LDL-C)≥3.36 mmol·l−1 ] . Subjects consumed each of six diets for 5-wk periods according to a r and omized crossover design . The experimental diets included a baseline diet ( 39 % energy as fat , 164 mg chol·4.2 MJ−1 ) and five reduced-fat diets ( 30 % of energy as fat ) , where two-thirds of the fat was either soybean oil ; squeeze , tub or stick margarines ; or butter . Fractional and absolute synthesis rates ( FSR and ASR ) of FC were determined using the deuterium incorporation ( DI ) method , while cholesterol precursor levels were measured using gas-liquid chromatography . Data were pooled across diets for each variable and correlation coefficients were calculated to determine if associations were present . There was good agreement among levels of the various cholesterol precursors . In addition , FSR in pools/d ( p·d−1 ) and ASR in grams/d ( g·d−1 ) were strongly associated with lathosterol ( r=0.72 and 0.71 , P=0.0001 ) , desmosterol ( r=0.75 and 0.75 , P=0.0001 ) , lanosterol ( r=0.67 and 0.67 ) , and squalene ( r=0.69 and 0.68 ) when levels of the precursors were expressed as μmol·mmol−1C . Significant but lower correlations were observed between the D uptake and plasma cholesterol precursor levels when the latter were expressed in absolute amounts ( μmol·L−1 ) . The wide range of fatty acid profiles of the experimental diets did not influence the degree of association between methods . In conclusion , the DI method and levels of some cholesterol precursors correspond as methods for shortterm measurement of cholesterol synthesis
In general , markers for cholesterol absorption and synthesis displayed reciprocal patterns , showing that cholesterol metabolism is tightly regulated by the interplay of intestinal absorption and endogenous synthesis .
Distinctive patterns for cholesterol absorption or cholesterol synthesis could be identified , suggesting that metabolic disorders can be classified as ' cholesterol absorbers or cholesterol synthesizers ' .
Non-cholesterol sterols are vali date d biomarkers for intestinal cholesterol absorption and endogenous cholesterol synthesis .
However , their use in metabolic disturbances has not been systematic ally explored .
Therefore , we conducted a systematic review to provide an overview of non-cholesterol sterols as markers for cholesterol metabolism in different metabolic disorders .