SREBP-1c gene polymorphism is associated with increased inhibition of cholesterol-absorption in response to ezetimibe treatment

OBJECTIVE

Sterol regulatory binding proteins 1 and 2 (SREBPs) are transcription factors regulating lipid metabolism. A recent study has associated the CC genotype of the SREBP-1c polymorphism G952G with increased cholesterol synthesis. Further evidence suggests that SREBPs play a role in cholesterol absorption and that SREBP polymorphisms modulate the response to statin therapy. The present study examines whether the G952G polymorphism alters cholesterol synthesis and/or absorption and whether it modulates the response to widely used lipid-lowering drugs such as inhibitors of cholesterol synthesis (simvastatin) or absorption (ezetimibe).

METHODS

Seventy-two healthy male subjects with LDL cholesterol <190 mg/dL participated in the study. Twenty four subjects were treated with ezetimibe (10 mg), simvastatin (40 mg) or their combination, respectively, for two weeks. Blood was drawn before and after the 2-week treatment period.

RESULTS

Eleven CC homozygous carriers of the gene were found (15%). There were no differences in cholesterol synthesis or absorption between the CC homozygotes and the G allele-carriers, as measured by the ratios to cholesterol of serum lathosterol, desmosterol and cholestenol (synthesis markers) and cholestanol, sitosterol and campesterol (absorption markers). Ezetimibe had a significantly more potent effect in blocking cholesterol absorption in the CC homozygotes compared to the G-carriers ( P=0.002).

CONCLUSIONS

The G/C (G952G) polymorphism of the SREBP-1 gene is not associated with cholesterol synthesis or absorption in a German male population. The CC homozygotes have a significantly increased response to the effects of ezetimibe on cholesterol absorption compared to the G allele-carriers, suggesting that SREBP-1 may be implicated in ezetimibe's mechanism of action.

Weight reduction modulates expression of genes involved in extracellular matrix and cell death: the GENOBIN study

OBJECTIVE

Lifestyle and genetic factors interact in the development of obesity and the metabolic syndrome. The molecular mechanisms underlying the beneficial dietary modifications are, however, unclear. We aimed to examine the effect of the long-term moderate weight reduction on gene expression in adipose tissue (AT) and to identify genes and gene clusters responsive to treatment and thereby likely contributing to the development of the metabolic syndrome.

DESIGN

Randomized controlled and individualized weight reduction intervention.

SUBJECTS

Forty-six subjects with impaired fasting glycemia or impaired glucose tolerance and features of metabolic syndrome, aged 60+/-7 years were randomized either to a weight reduction (WR) (n=28) or a control (n=18) group lasting for 33 weeks.

MEASUREMENTS

Oral and intravenous glucose tolerance tests and subcutaneous AT biopsies were performed before and after the intervention. Gene expression of AT was studied using microarray technology in subgroups of WR (with weight reduction > or =5%, n=9) and control group (n=10). The results were confirmed using quantitative PCR.

RESULTS

In the WR group, glucose metabolism improved. Moreover, an inverse correlation between the change in S (I) and the change in body weight was found (r=-0.44, P=0.026). Downregulation of gene expression (P<0.01) involving gene ontology groups of extracellular matrix and cell death was seen. Such changes did not occur in the control group. The tenomodulin-gene was one of the most downregulated genes (-39+/-16%, P<0.0001). Moreover, its expression correlated with insulin sensitivity (r=-0.34, P=0.005) before the intervention and with body adiposity both before (r=0.42, P=0.007) and after (r=0.30, P=0.056) the intervention.

CONCLUSION

Genes regulating the extracellular matrix and cell death showed a strong downregulation after long-term weight reduction. This likely reflects a new stable state at the molecular level in AT. Further studies are warranted to elucidate the mechanisms of these genetic factors.

Moderate increase in dietary sucrose does not influence fasting or postprandial serum lipids regardless of the presence of apolipoprotein E2 allele in healthy subjects

OBJECTIVE

To investigate whether a moderate increase in dietary sucrose intake induces different serum lipid responses in normolipidemic subjects with the epsilon 2 allele compared with subjects without the epsilon 2 allele.

DESIGN

Controlled, parallel study.

SUBJECTS

There were 15 subjects with the apolipoprotein E (APOE)3/2 genotype and 19 subjects with the APOE 3/3 or 3/4 genotype, whose mean+/-s.d. age was 48+/-14 and 35+/-10 years, respectively. All subjects had normal glucose metabolism.

INTERVENTIONS

The subjects were instructed to increase their sucrose intake by 40 g/day for 8 weeks and to decrease the intake of saturated and unsaturated fat to maintain energy balance. Dietary adherence was monitored using food records and the actual increase in sucrose intake was 39.8+/-18.4 g/day. Sixteen subjects (nine with APOE 3/2 genotype, seven with APOE 3/3 or 3/4 genotypes) participated also in an 8 h oral fat tolerance test at the beginning and at the end of the intervention.

RESULTS

Body weight remained stable during the intervention. Sucrose intake did not have a significant effect on fasting concentrations of serum total and lipoprotein lipids, plasma glucose, serum insulin, squalene and non-cholesterol sterols in either genotype group. Neither were there any changes in postprandial lipid or insulin responses.

CONCLUSIONS

Moderate increase in sucrose intake does not affect fasting or postprandial serum lipid responses in healthy subjects with or without the epsilon 2 allele.

Postprandial behavior of plasma squalene and non-cholesterol sterols in men with varying cholesterol absorption

BACKGROUND

The purpose of this study was to investigate, whether low vs. high absorption of cholesterol affects the postprandial lipid clearance (squalene as the surrogate marker) and postprandial cholesterol metabolism evaluated with plasma levels of cholesterol absorption (cholestanol and plant sterols) and synthesis markers (desmosterol and lathosterol).

METHODS

Fifteen normo- or mildly hypercholesterolemic men were divided into low or high cholesterol absorbers on the basis of plasma cholestanol to cholesterol ratio and they volunteered to an oral fat load test containing fat 35 g/m(2) body surface.

RESULTS

Plasma squalene to cholesterol ratio did not differ between the groups throughout the postprandial follow-up of 8 h. The level differences in the plasma absorption and synthesis markers seen at baseline remained between the groups, so that in high absorbers the absorption markers remained high and synthesis markers low throughout the postprandial follow-up. The postprandial response curves of desmosterol (p<0.05) and lathosterol (p=0.052) to cholestanol decreased linearly in the low, but not in the high absorbers.

CONCLUSIONS

Low vs. high absorption of cholesterol does not affect the first 8-h postprandial lipid clearance. The metabolic profile of cholesterol is maintained postprandially. The postprandial decrease in cholesterol synthesis differs in low vs. high absorbers especially through the desmosterol pathway.

Plant stanol and sterol esters in prevention of cardiovascular diseases: a review

Plant sterol and stanol esters have been introduced as an additional dietary means to lower serum total and LDL cholesterol concentration. In short-term studies they lower LDL cholesterol by 10%, and according to a meta-analysis by Malcolm Law the incidence of coronary heart disease is considered to be reduced by over 20% in long-term use of these products. Plant stanol and sterol esters are not identical sterols; they have different metabolic effects and their long-term efficacy seems to be different. The present review deals with the differences of the sterols and discusses what is known of their role in preventing the cardiovascular diseases.

Cholesterol metabolism and its implications for therapeutic interventions in patients with hypercholesterolaemia

Cardiovascular diseases are the principal causes of mortality in middle-aged people and in older people. Coronary heart disease (CHD) is the most common of the cardiovascular diseases; high serum levels of cholesterol are associated with atherosclerosis and an increased risk of CHD. Cholesterol homeostasis is achieved by means of a fine balance between cholesterol intake, absorption/excretion and synthesis. All of these processes are tightly linked and a change in one of them can significantly influence the others. Results from both experimental studies and clinical trials have shown that inhibition of cholesterol synthesis with a statin increases absorption and that conversely, inhibition of cholesterol absorption increases synthesis. The tight linkage of cholesterol absorption and synthesis in maintaining cholesterol homeostasis suggests that treatment with an agent that influences only one of these two processes is likely to have distinct limits with respect to its effects on cholesterol levels. Better understanding of cholesterol homeostasis, particularly the close interrelationship between cholesterol synthesis and absorption, may result in the design of rational integrated treatment regimens that employ multiple agents with complementary actions that attack multiple mechanisms to lower cholesterol.

Synthesis and absorption markers of cholesterol in serum and lipoproteins during a large dose of statin treatment

BACKGROUND

Serum contains noncholesterol sterols, which are reliable markers of cholesterol metabolism, but their presence and importance in different lipoproteins have been insufficiently studied.

MATERIALS AND METHODS

Serum and lipoprotein cholesterol precursors squalene, cholestanol, desmosterol and lathosterol (markers of cholesterol synthesis) and cholestanol and plant sterols (markers of cholesterol absorption), and absorption efficacy and absolute synthesis of cholesterol were studied at baseline and during 6-month atorvastatin (80 mg day(-1)) treatment by the sterol balance technique in men with type 2 diabetes.

RESULTS

At baseline, approximately 14% of serum squalene was transported by VLDL, 12% by IDL, 40% by LDL and 30% by HDL. The respective values for the noncholesterol sterols were approximately 8, 4, 61 and 26%. The squalene to cholesterol ratios were highest in VLDL and IDL, those of cholestanol, desmosterol and absorption marker sterols were gradually higher, and that of lathosterol lower from VLDL to HDL. Atorvastatin reduced LDL cholesterol by approximately 50%, decreased the absolute cholesterol synthesis and turnover by approximately 40%, but increased significantly the fractional and mass absorption of cholesterol. In accordance with the fecal data, the ratios of the precursor sterols to cholesterol were reduced (-50%), but those of squalene (+48%) and the absorption sterols increased (e.g. 2.6-fold for sitosterol) similarly in each lipoprotein, but progressively from VLDL to HDL.

CONCLUSIONS

Effective lowering of LDL cholesterol by large dose of statin is associated with decreased synthesis and turnover of cholesterol and increased fractional and mass absorption of cholesterol. These changes are detectable by noncholesterol sterols in serum and in different lipoprotein fractions.

Effects of gender, apolipoprotein E phenotype and cholesterol-lowering by plant stanol esters in children: the STRIP study. Special Turku Coronary Risk Factor Intervention Project

AIM

To evaluate the effects of gender, apolipoprotein E phenotype and cholesterol absorption and synthesis (estimated as serum plant sterol and cholesterol precursor sterol concentrations) on the cholesterol-lowering effect of plant stanol esters in children.

METHODS

Eighty-one healthy, normocholesterolaemic 6-y-old children (45 boys) were recruited from the Special Turku Coronary Risk Factor Intervention Project (STRIP), a randomized prospective trial aiming at atherosclerosis prevention in childhood. This placebo-controlled, double-blind, cross-over study comprised two 3-mo study periods and a 6-wk wash-out period. During the study periods, 20 g of the children's daily dietary fat intake was replaced with plant stanol ester margarine or control margarine.

RESULTS

In boys, plant stanol esters reduced serum total and low-density lipoprotein cholesterol concentrations by 6% (0.09 to 0.42 mmol/L) and 9% (0.09 to 0.36 mmol/L), respectively (p < 0.01 for both). In girls, the decreases in concentrations were 4% (0.03 to 0.38 mmol/L) and 6% (0.02 to 0.32 mmol/l) (p < 0.05 for both). The response rate did not differ between the genders. Serum total and low-density lipoprotein cholesterol concentrations decreased by 6% and 8% (p < 0.01 for both), respectively, in both children with the apolipoprotein E 3/4 or 4/4 (apoE4+) phenotype and the apolipoprotein E 2/3 or 3/3 (apoE4-) phenotype. Cholesterol absorption decreased both in the apoE4+ children and in the apoE4- children, but cholesterol synthesis consistently increased in the apoE4+ children only.

CONCLUSION

Plant stanol esters reduce serum cholesterol concentration in healthy children irrespective of their gender or apoE4 phenotype.

LDL cholesterol lowering by bile acid malabsorption during inhibited synthesis and absorption of cholesterol in hypercholesterolemic coronary subjects

BACKGROUND AND AIMS

Recent large-scale trials have consistently documented the fact that a 25-35% reduction in low-density lipoprotein cholesterol (LDL-C) can delay the progression of atherosclerosis. This raises the question as to how much it is possible to reduce serum cholesterol using feasible therapies. The aim of this study was to investigate the cholesterol-lowering efficacy of a triple therapy combining bile acid malabsorption with the inhibition of cholesterol synthesis and absorption.

METHODS AND RESULTS

Eleven consecutive hypercholesterolemic coronary patients from Lipid Clinics on a low-fat, low-cholesterol baseline diet added simvastatin (20 mg/day) for three months, and then dietary plant stanol ester margarine (2.25 g of stanols/day) for eight weeks; finally, cholestyramine 8 g/day was added for another eight weeks. This was a before-after trial, in which the results of each period were compared with baseline and those of the previous period. Serum lipids were quantitated using commercial kits, and serum sterols by means of gas-liquid chromatography. Simvastatin lowered LDL-C by 39% (p < 0.001), and additional stanol ester margarine by a further 13% (p < 0.05). The triple treatment led to 67% reduction from baseline (p < 0.001), with all LDL-C values being < 2.6 mmol/L, and increased high-density lipoprotein cholesterol (HDL-C) by 15% (p < 0.01). It also increased the serum lathosterol/cholesterol ratio (p < 0.01), thus indicating an upregulation of cholesterol synthesis, and increased the serum sitosterol ratio (p < 0.01) despite the simultaneous consumption of plant stanols.

CONCLUSIONS

The massive reduction in LDL and increase in HDL-C obtained using our triple therapy suggests that the combination of stanol ester with only moderate doses of statin and resin makes it possible to control LDL-C levels effectively in hypercholesterolemic subjects.

Baseline intestinal absorption and synthesis of cholesterol regulate its response to hypolipidaemic treatments in coronary patients

Baseline cholesterol metabolism was hypothesized to regulate responses of cholesterol synthesis and absorption, and serum cholesterol lowering to hypolipidaemic treatment. Thus, serum cholesterol and non-cholesterol sterols were measured before and during long-term simvastatin treatment (inhibition of cholesterol synthesis) and subsequent combination of statin with plant stanol ester margarine (inhibition of cholesterol absorption) consumption in subjects with low (n=15) and high (n=15) absorption of cholesterol, defined by respective low and high baseline ratios of serum cholestanol to cholesterol. Cholesterol synthesis (defined by precursors of cholesterol) was markedly reduced by the long-term statin treatment in both groups, but more extensively in the low than high absorption group (P<0.05), yet the respective serum cholesterol reductions were similar. From among the absorption markers, sitosterol and cholestanol ratios were correspondingly increased more in the low than in the high absorption group. Plant stanol ester margarine consumption, combined with chronic statin treatment, further lowered the serum cholesterol level (P<0.001) only in the high absorption group. The sum of cholesterol absorption markers was reduced more (P<0.05) in the high than in the low absorption group, while the non-significant serum cholesterol reduction of the low absorption group was associated with relatively high increase of cholesterol synthesis. Thus, stanol ester margarine combined with chronic simvastatin treatment reduces cholesterol absorption and serum cholesterol more consistently in subjects with high than low baseline absorption of cholesterol. The profile of baseline cholesterol metabolism determines the changes in synthesis and absorption of cholesterol to hypolipidaemic treatments, but affects less differently serum cholesterol level.

Apolipoprotein E phenotype regulates cholesterol absorption in healthy 13-month-old children--The STRIP Study

High serum cholesterol concentration is one of the key risk factors in development of atherosclerosis, which may begin early in life and later progress to symptomatic coronary heart disease. In adults, apoE polymorphism strongly influences cholesterol metabolism, as subjects with apoE 3/4 or 4/4 (collectively called apoE4) phenotype absorb cholesterol effectively and thus also have higher cholesterol absorption-reflecting plant sterol concentrations in serum than subjects with other apoE phenotypes. Because of the inverse correlation of absorption and synthesis of cholesterol, concentrations of cholesterol synthesis-reflecting serum cholesterol precursor sterols are lower in subjects with apoE4 than in subjects with other phenotypes. To analyze whether apoE phenotype affects cholesterol absorption and synthesis in early childhood, we measured serum plant sterol (campesterol and sitosterol) and cholesterol precursor sterol (desmosterol and lathosterol) concentrations in healthy 13-month old children using gas-liquid chromatography. The 36 study children were participants in a randomized prospective trial (the Special Turku Coronary Risk Factor Intervention Project) aimed at decreasing exposure of the children to environmental atherosclerosis risk factors. The 16 apoE4 children had 30% to 50% higher cholesterol-adjusted campesterol and sitosterol concentrations in serum than the 20 apoE 3/3 children (p = 0.002 and p = 0.02, respectively). The concentrations of cholesterol precursor sterols in serum did not differ between the two groups of children. We conclude that the young apoE4 children may absorb cholesterol and plant sterols more effectively than the children with apoE 3/3 phenotype without compensatory reduction in endogenous synthesis of cholesterol.

Cholesterol absorption, synthesis, and fecal output in postmenopausal women with and without coronary artery disease

Hypercholesterolemia is a prominent risk factor for coronary artery disease (CAD), yet cholesterol metabolism has not been evaluated in women with CAD. The objective of this study was to determine the interrelations of CAD, serum squalene and sterols, and cholesterol metabolism with each other in postmenopausal women. For this purpose, we measured serum squalene and sterols and fecal steroids (cholesterol and bile acids) and squalene by gas-liquid chromatography and evaluated cholesterol absorption and synthesis in postmenopausal women with CAD (n=29) and age-matched controls (n=20). On similar dietary lipid intake, the cholesterol absorption efficiency and mean serum cholesterol level were comparable, but the squalene-to-cholesterol ratio was higher in cases than in controls. The presence of CAD was inversely associated with fecal total steroids (logistic regression coefficient beta/SE=-2.11, P=0.04) and cholesterol synthesis (beta/SE=-2.14, P=0.04) and turnover (beta/SE=-2.19, P=0.03) after adjustment for dietary cholesterol, family history of CAD, smoking, low and high density lipoprotein cholesterol, and serum triglyceride levels. A high serum squalene ratio was not related to cholesterol synthesis but was inversely related to fecal squalene excretion, which was lower in cases than in controls. In conclusion, the presence of CAD in postmenopausal women is independently associated with altered cholesterol metabolism, as reflected by low synthesis and inefficient elimination of cholesterol.

Dyslipidemia and a reversible decrease in insulin sensitivity induced by therapy with 13-cis-retinoic acid

BACKGROUND

13-cis-Retinoic acid (Roaccutan) treatment is associated with disturbances in lipid and sometimes also in glucose metabolism. Thus, we investigated whether 13-cis-retinoic acid treatment decreases insulin sensitivity.

METHODS

We studied 11 men [aged 24+/-2 years (mean+/-SEM), body mass index (BMI) 22.1+/-0.9 kg/m(2)] who received Roaccutan treatment for acne for a period averaging 5 months but who were otherwise healthy. The insulin sensitivity of the subjects was measured before, during and 1-3 months after the end of treatment using the euglycaemic hyperinsulinaemic clamp technique.

RESULTS

Treatment with 13-cis-retinoic acid reduced total (59+/-4 vs 55+/-4 micromol/kg/min, p<0.02), oxidative (25+/-1 vs 22+/-2 micromol/kg/min, p<0.05) and non-oxidative (36+/-3 vs 33+/-3 micromol/kg/min, p=0.05) glucose disposal rate, and there was a 4% increase in HbA(1c) (from 5.2+/-0.07 to 5.4+/-0.07%, p<0.02). After treatment cessation these values returned to baseline. 13-cis-Retinoic acid treatment also resulted in increased very low density lipoprotein (VLDL) and low density lipoprotein (LDL) cholesterol, increased VLDL triglyceride, and increased VLDL and LDL phospholipid concentrations.

CONCLUSION

Treatment of acne with 13-cis-retinoic acid reduces insulin sensitivity and induces alterations in lipid metabolism resembling those of the insulin resistance syndrome.

Familial hypercholesterolaemia in Finland: common, rare and mild mutations of the LDL receptor and their clinical consequences. Finnish FH-group

Familial hypercholesterolaemia (FH) is an autosomal co-dominantly inherited condition resulting from mutations of the low-density lipoprotein (LDL) receptor which occur in heterozygous form in approximately one in 500 individuals. Clinically, FH is characterized by 2-3-fold elevation of serum LDL cholesterol levels, accelerated development of atherosclerotic vascular disease, and, if untreated, shortened lifespan. The Finnish population, which represents a genetic isolate, offers exceptional possibilities for genetic-epidemiological studies on FH, as a handful of founder gene mutations account for the majority of FH cases in Finland. This review summarizes data from our FH studies carried out since 1985. We wish to emphasize the continuum of genotype-phenotype relationships, the importance of molecular diagnosis, the detection of novel risk factors of vascular disease, and innovations inhibiting cholesterol absorption for the modern treatment of FH.

Dietary plant sterols alter the serum plant sterol concentration but not the cholesterol precursor sterol concentrations in young children (the STRIP Study). Special Turku Coronary Risk Factor Intervention Project

Plant sterol supplementation reduces serum cholesterol concentration but may increase serum plant sterol concentrations, especially in children. We determined whether natural dietary plant sterols derived mainly from vegetable oil or margarine in early childhood affect serum concentrations of plant sterols (campesterol and sitosterol) and cholesterol precursor sterols (Delta-8 cholestenol, desmosterol, and lathosterol), reflecting endogenous cholesterol synthesis. We measured the serum sterol concentrations using gas liquid chromatography in 20 healthy 13-mo-old intervention children in a randomized, prospective study designed to decrease exposure of the children to known environmental atherosclerosis risk factors and in 20 control children. The diet of the intervention children was rich in plant sterols due to replacement of milk fat with vegetable fat, whereas the diet of the control children contained only small amounts of plant sterols. The intervention children consumed twice as much plant sterols as the control children (P < 0.001). Their serum concentrations of campesterol and sitosterol were 75% and 44% higher, respectively, than those in the control children (P < 0.001 for both), but serum cholesterol precursor sterol concentrations did not differ between the two groups. We conclude that doubling dietary plant sterol intake almost doubles serum plant sterol concentrations in 13-mo-old children, but has no effect on endogenous cholesterol synthesis. Relative intestinal absorption of natural plant sterols from the diet in early childhood is similar to that in adults.

Fate of intravenously administered squalene and plant sterols in human subjects

We have studied metabolism of plant sterols and squalene administered intravenously in the form of lipid emulsion mimicking chylomicrons (CM). The CM-like lipid emulsion was prepared by dissolving squalene in commercially available Intralipid. The emulsion was given as an intravenous bolus injection of 30 ml containing 6.3 mg of cholesterol, 1.9 mg of campesterol, 5.7 mg of sitosterol, 1.6 mg of stigmasterol, 18.1 mg of squalene, and 6 g of triglycerides in six healthy volunteers. Blood samples were drawn from the opposite arm before and serially 2.5 -180 min after the injections. The decay of CM squalene, plant sterols, and triglycerides was monoexponential. The half-life of CM squalene was 74 +/- 8 min, that of campesterol was 37 +/- 5 min (P < 0.01 from squalene), and those of sitosterol, stigmasterol, and triglycerides were 17 +/- 2, 15 +/- 1, and 17 +/- 2 min, respectively (P < 0.01 from squalene and campesterol). The CM squalene concentration still exceeded the baseline level 180 min after injection (P = 0.02), whereas plant sterols and triglycerides returned to the baseline level between 45 and 120 min after injection. The half-lives of squalene and campesterol were positively correlated with their fasting CM concentrations. In addition, VLDL squalene, campesterol, and triglyceride concentrations, VLDL, LDL, and HDL sitosterol concentrations, as well as VLDL and LDL stigmasterol concentrations were increased significantly. Cholesterol concentrations increased in VLDL (P < 0.05), but were unchanged in CM after injection. These data suggest that squalene clearance occurs more slowly than that of plant sterols and triglycerides from CM, and that squalene is more tightly associated with triglyceride-rich lipoproteins than are plant sterols in injected CM-like emulsions.

Acute effect of dietary stanyl ester dose on post-absorptive alpha-tocopherol, beta-carotene, retinol and retinyl palmitate concentrations

Stanyl esters dissolved in margarine inhibit cholesterol absorption, lower sterol absorption in general, and lower serum total cholesterol, LDL-cholesterol and plant sterol levels. To find out whether stanyl esters inhibit absorption of fat-soluble vitamins and beta-carotene in acute experiments, we performed two fat-tolerance tests fortified with vitamins (retinol 0.9-3.7 mg, alpha-tocopherol 70-581 mg), beta-carotene (25-150 mg) and squalene (0.5 g) with and without 1 g of stanyl ester added to the test meal in ten healthy men. The concentrations or areas under the curves (AUC) of cholesterol, triacylglycerols, squalene and alpha-tocopherol, beta-carotene and retinyl palmitate showed typical postprandial changes in serum, chylomicrons, VLDL and VLDL infranatant (intermediate-density lipoproteins, LDL and HDL) over 24 h after the test meal without stanyl esters, and they were not affected by the addition of stanyl esters. The post-absorptive serum campesterol concentration and campesterol : cholesterol were significantly lowered at 6-9 h by stanyl ester supplementation, reflecting reduced sterol absorption efficiency. Changes in vitamin and beta-carotene AUC did not correlate with the given doses. In conclusion, the present study shows that stanyl esters dissolved in margarine do not detectably interfere in a short-term study with the absorption of alpha-tocopherol, beta-carotene or retinol measured by a 24 h oral fat-load test.