Epidemiological evidence has shown that men consuming a low-fat, high-fiber diet containing high amounts of plant products have a lower risk of prostate cancer than men consuming a Western diet. One of the main differences between these two diets is the type of dietary fat, including dietary sterols. This study ...

We investigated the effect of sitosterol on hepatic sterol 27-hydroxylase activities in subjects with sitosterolemia, a recessive inherited disease associated with accelerated atherosclerosis and increased levels of sitosterol and other plant sterols and stanols in tissues. Hepatic activities of mitochondrial sterol 27-hydroxylase, which catalyzes the first step in the conversion ...

BACKGROUND: Reduction of serum cholesterol decreases mortality in primary and especially in secondary prevention. We investigated how effectively postmenopausal women with a previous myocardial infarction reduced their serum cholesterol with dietary means by using sitostanol ester rapeseed oil margarine, alone and in combination with statins, and to what extent cholesterol ...

OBJECTIVE: Sitosterolemia is a genetic disorder characterized by an increased plasma plant sterol concentration due to enhanced sterol absorption coupled with reduced steroid excretion. The purpose of the present investigation was two-fold; first to assess the effects of a "basal" low sitosterol metabolic diet on plasma sterols and sterol balance, ...

BACKGROUND: Transplantation of the small intestine impairs intestinal absorptive function, but the adaptive response of a segmental graft is unknown. The aim of this study was to investigate the effects of ileal autotransplantation on the adaptive absorption and metabolism of lipids in pigs that had undergone proximal gut resection. METHODS: ...

The effect of Prunus amygdalus, which is rich in unsaturated fat, fibre diet and low cholesterol was studied in 36 normolipidemic male albino rabbits for 60 days. Three different doses i.e. whole seeds defatted and oil showed a decrease in serum total cholesterol, triglyceride, LDL cholesterol, VLDL cholesterol and an ...

OBJECTIVE AND SUBJECTS: Dietary fibre has been suggested to interfere with endogenous cholesterol synthesis in the liver. Therefore the effects of oat bran on the proportions of cholesterol synthesis precursors (squalene, delta(8-) cholesterol, desmosterol and lathosterol), cholestanol and plant sterols (campesterol and beta-sitosterol) to cholesterol were analysed in serum of ...

To confirm that blocking 7-dehydrocholesterol delta 7 reductase (7DHC reductase), as observed in Smith-Lemli-Opitz syndrome (SLOS), induces craniofacial defects, we tested BM15.766, which blocks 7DHC reductase but is chemically unrelated to the holoprosencephaly-inducing teratogen AY9944. Rats were given BM15.766 either in methylcellulose from days (D) 1 through D11 (3 treated ...

These studies were done to determine whether an underlying metabolic difference could account for the higher concentration of cholesterol carried in low density lipoproteins (LDL-C) in male hyperresponder (HR) cynomolgus monkeys than in their hyporesponder (HO) counterparts during dietary cholesterol challenge. All animals were fed to steady state at 5 ...

(I) There is little discrimination between cholesterol and the plant sterol sitosterol in the uptake at the brush border membrane (BBM). (II) This difference cannot account for the marked discrimination between cholesterol and sitosterol observed in the absorption of these two sterols by the small-intestinal epithelium. (III) This discrimination occurs ...

The neutral sterols of the parasitic mite Varroa jacobsoni were compared with Apis mellifera carnica drone pupae. Analysis by GLC-mass spectrometry indicated mite sterols were reflective of the sterol composition of the drones; 24-methylenecholesterol was the major sterol in both species, with lesser amounts of sitosterol and isofucosterol. Cholesterol accounted ...

BACKGROUND: Previous studies suggest only minor changes in bile acid metabolism after panproctocolectomy with ileal pouch construction. AIMS/METHODS: To investigate these changes further, we studied cholesterol absorption and serum, biliary and fecal non-cholesterol sterols and lipids in 12 ileal pouch patients and 10 controls. RESULTS: In patients, cholesterol absorption was ...

Phytosterolaemia (sitosterolaemia) is a very rare inherited sterol storage disease characterized by tendon and tuberous xanthomas and by a strong predisposition to premature coronary atherosclerosis. In addition to increased or normal serum cholesterol, patients are found to have markedly elevated concentrations of the phytosterols sitosterol and campesterol. These sterols accumulate ...

Phytosterols (plant sterols), abundant in fat-soluble fractions of plants, are consumed at levels of 200-400 mg/day in Western diets. Chemically resembling cholesterol, phytosterols inhibit the absorption of cholesterol. Phytosterol consumption in human subjects under a wide range of study conditions has been shown to reduce plasma total and low density ...

OBJECTIVE: To determine the effects of the reduction of intestinal cholesterol absorption with CP-148,623 on serum cholesterol levels in men with mild hyperlipidemia. METHODS: In an outpatient study in a university medical center, healthy male volunteers (n = 25) with borderline-high serum cholesterol levels participated in a double-blind, placebo-controlled parallel-group ...

This study was conducted to determine whether the storage conditions and the levels of psyllium in the diet modulate its hypocholesterolemic effects. Seventy-five male Sprague-Dawley rats, age 90 d, were randomly divided into five treatment groups and were fed cholesterol-containing diets for 21 d. Diets included 10% cellulose (control); 5 ...

Litholytic bile acid ursodeoxycholic acid (UDCA) reduces biliary cholesterol secretion and alters cholesterol metabolism by mechanisms that are not fully understood. To evaluate cholesterol metabolism during UDCA treatment, we studied serum and biliary lipids and cholesterol precursor sterols (lanosterol and other dimethyl and monomethyl sterols, lathosterols, and desmosterol), indicators of ...

CaCo-2 cells were used to address the effect of the plant sterol, beta-sitosterol, on cholesterol trafficking, cholesterol metabolism, and apoB secretion. Compared to cells incubated with micelles (5 mM taurocholate and 250 microM oleic acid) containing cholesterol, which caused an increase in the influx of plasma membrane cholesterol to the ...

Tint et al. [N Engl J Med 1994, 330:107-113], working with blood samples from the Smith-Lemli-Opitz syndrome (SLOS) patients of Irons and Elias showed the biochemical basis of this disorder to be a cholesterol biosynthesis defect [Irons et al., Lancet, 1993, 341:1414]. Based on this finding, clinical protocols for cholesterol ...

Dietary cholesterol metabolism was studied, using a single dose of emulsion, per os (test meal), in lines of Japanese quail that were divergently selected for high (HL) and low (LL) plasma total cholesterol. The meal contained [3H] cholesterol, [14C] beta-sitosterol, unlabeled cholesterol, triolein, and bile salt. Recovery of the nonabsorbable ...

OBJECTIVE: Cholesterol and lipoprotein metabolism was studied in mildly hypercholesterolemic nonobese men with NIDDM to find out which metabolic parameters regulate serum cholesterol level in these NIDDM subjects. RESEARCH DESIGN AND METHODS: Nonobese NIDDM subjects (n = 13) and control subjects (n = 18) with serum cholesterol > or = ...

The present study was designed to examine the incorporation of phytosterols (PS) in membranes and tissues of rats fed a diet containing 2% PS in the presence of 0.2% cholic acid for 22 days. The control diet contained 12 mg PS/100 g compared with 2,012 mg/100 g. Liver, kidney, testis, ...

A fetal hamster increases in mass almost 100-fold in the third trimester of gestation. During this 5.5-day period, the acquisition of over 4 mg of cholesterol is required for normal development. The purpose of the present studies was to determine the potential source(s) of this fetal sterol. Rates of cholesterol ...

The Smith-Lemli-Opitz syndrome is caused by an inherited defect in 7-dehydrocholesterol-delta7-reductase, the enzyme that catalyzes the last reaction in cholesterol biosynthesis, the conversion of 7-dehydrocholesterol to cholesterol. As a result, deficient cholesterol is produced and the precursor 7-dehydrocholesterol and derivatives (8-dehydrocholesterol and 19-nor-5,7,9(10)-cholestatrien-3 beta-ol) accumulate. Tissues (especially brain) deprived of ...

We review some of the older literature concerning metabolic turnover of cholesterol in the nervous system. The overall picture is that incorporation of radioactive precursors into brain cholesterol is roughly proportional to the rate of myelination and that, once incorporated, radioactive cholesterol is relatively stable metabolically. We outline a strategy ...

Cells acquire cholesterol through endogenous synthesis and through receptor-mediated uptake of cholesterol-rich low density lipoprotein (LDL). Esterification of LDL-derived cholesterol is catalyzed by acyl-CoA:cholesterol acyltransferase (ACAT) in the endoplasmic reticulum (ER). Progesterone inhibits esterification, and, although the mechanism of inhibition is not completely understood, this inhibition results from progesterone's ability ...

Multidrug resistance (MDR) P-glycoproteins were first recognized for their ability to catalyze ATP-dependent efflux of cytotoxic agents from tumor cells when overexpressed. Despite extensive study, little is known about the normal substrate(s) and normal cellular function of these proteins. In the accompanying manuscript (Metherall, J. E., Waugh, K., and Li, ...

The hepatic uptake, transport, and secretion into bile of unesterified cholesterol cannot be directly quantitated because of extensive exchange and equilibration between different pools of unesterified cholesterol. Plant sterols are structurally similar to cholesterol but because of poor intestinal absorption are ordinarily not present in the liver. To quantitate hepatic ...

Inherited defects in enzymes of cholesterol metabolism and use of drugs which inhibit lens cholesterol biosynthesis can be associated with cataracts in animals and man. The basis of this relationship apparently lies in the need of the lens to satisfy its sustained requirement for cholesterol by on-site synthesis, and impairing ...

We investigated the enzyme defects in two inherited disorders of cholesterol biosynthesis: sitosterolaemia and the Smith-Lemli-Opitz syndrome. In sitosterolaemic homozygotes, plasma plant sterols (sitosterol and campesterol) concentrations are elevated because of enhanced intestinal absorption and diminished removal. Underlying these changes is very low cholesterol biosynthesis to provide extra sterol for ...

PURPOSE: Long-term effects of tamoxifen and toremifene, a new antiestrogen that closely resembles tamoxifen, were investigated on serum lipids and cholesterol metabolism. PATIENTS AND METHODS: The study group consisted of 24 postmenopausal Finnish women with advanced breast cancer from an international multicenter study of 415 patients. Cholesterol metabolism was evaluated ...

To investigate the action and mechanism of a dietary phytosterol mixture naturally containing sitostanol, derived from tall-oil, on circulating cholesterol and lipoprotein levels, five groups of rats were fed a control elemental diet (group 1), a control elemental diet with 1% cholesterol alone (group 2) or with sitostanol mixtures or ...

BACKGROUND: Dietary plant sterols, especially sitostanol, reduce serum cholesterol by inhibiting cholesterol absorption. Soluble sitostanol may be more effective than a less soluble preparation. We tested the tolerability and cholesterol-lowering effect of margarine containing sitostanol ester in a population with mild hypercholesterolemia. METHODS: We conducted a one-year, randomized, double-blind study ...

For over a decade investigators have quantified cholesterol absorption by comparison of dietary intake and fecal excretion of isotopic cholesterol with that of beta-sitosterol as a "nonabsorbable" marker. However, beta-sitosterol might not be ideal due to its potential for absorption. We therefore carried out two studies to evaluate a new ...

This study examines the therapeutic outcome of a low plant sterol diet and adjunctive drug therapy (cholestyramine) in the long term treatment of beta-sitosterolemia. A diet restricted in plant sterols, cholesterol and fat was implemented in a 48-year-old male beta-sitosterolemic patient. The plant sterols beta-sitosterol, campesterol and stigmasterol, and cholesterol ...

In familial hypercholesterolemia (FH) the lowering of serum cholesterol levels should be started in childhood in order to prevent coronary artery disease later in life. However, treatment of children is problematic. We studied the effects of sitostanol (3 g/day) ester dissolved in rapeseed oil margarine as a hypocholesterolemic agent in ...

The effect of Jew's mellow leaf powder and its water soluble viscous substance on cholesterol metabolism in rats fed a high cholesterol diet was examined. When compared to the controls, total serum and liver cholesterol concentrations were significantly decreased or tended to decrease in the groups given dry powder of ...

Absorption of dietary cholesterol, campesterol, and sitosterol, cholesterol balance, and fecal excretion of plant sterols were determined in three unrelated patients with phytosterolemia and three healthy volunteers during constant intake of cholesterol and plant sterols using accurate gas-liquid chromatography-mass spectrometry techniques. Each subject received a mixture of [26,26,26,27,27,27-2H6]cholesterol, [6,7,7-2H3]sitostanol, and ...

The effect of melatonin on cholesterol metabolism in the rat was investigated in the dietary and hypothyroid models of hypercholesterolemia. In normal and dietary hypercholesterolemia (induced by 1% cholesterol, 0.5% bile acid), melatonin treatment (12.5mg/kg i.p.) reduced total serum cholesterol concentration and total low density lipoprotein (VLDL+LDL) cholesterol. The protective ...

A significant accumulation of cellular free cholesterol and steryl esters is observed in J774 macrophages when cells are exposed to low-density lipoproteins (LDL) containing cholesterol 5 beta,6 beta-epoxide. This cellular sterol accumulation is mainly due to the formation of esterified cholesterol and desmosterol. Cellular steryl esters increased to 39.4 and ...

Larvae of Drosophila melanogaster were reared aseptically on defined diets containing either cholesterol, campesterol or sitosterol as the only dietary sterol. Sterol analyses of pupae revealed that insects reared on campesterol and sitosterol diets contained 3.3 and 8.1% cholesterol, indicative of an ability to accumulate this sterol. Ecdysone and 20-hydroxyecdysone ...

The study evaluates cholesterol metabolism off and on treatment with pravastatin (P), gemfibrozil (G) and their combination (PG) in 38 middle-age hyperlipidemic primary care patients with serum cholesterol > 6 mmol/l and serum triglycerides < 4 mmol/l after a low-fat low-cholesterol diet. The subjects were randomized to P (40 mg/g), ...

A randomized placebo-controlled 2-year study was performed in 69 patients with primary biliary cirrhosis (PBC) on serum lipids during ursodeoxycholic acid (URSO) and colchicine treatments. In addition to serum bilirubin and alkaline phosphatase (AFOS), two variables considered to reflect liver function, serum lipoproteins, cholesterol precursors (squalene, delta 8-cholestenol, lathosterol and ...

Postprandial fat clearance and absorption, fecal elimination and synthesis of cholesterol, bile acid synthesis, and cholesterol precursors and plant sterols in serum were studied in five patients with type III dyslipoproteinemia off and on lovastatin. The basal values were related to those in nontreated normolipidemic control subjects with apolipoprotein E3/3 ...

The efficacy of garlic as a lipid-lowering agent is being increasingly recognized, but the biochemical mechanisms underlying this action are currently unknown. It is proposed that organic tellurium compounds, which are found in high concentration in fresh garlic buds, may contribute to this action by inhibiting squalene epoxidase, the penultimate ...

We examined whether cholesterol needed for myelin formation is locally synthesized or whether it comes from the circulation. The experimental design was to inject [3H]water and to use incorporation of label into brain cholesterol as a measure of the rate of accumulation of newly synthesized cholesterol in brain. The contribution ...

Plant sterols have been shown to reduce dietary cholesterol absorption and hence, total and low-density-lipoprotein (LDL)-cholesterol concentrations in humans. In this study the cholesterol-lowering effects of dietary supplementation with the hydrogenated plant sterol sitostanol (3 g/d) were tested in 33 men with moderate hypercholesterolemia who were consuming an outpatient diet ...

Azaspiranes are novel immunomodulators which are effective in a variety of autoimmune diseases. One azaspirane analog, SK&F 105685 (N,N-dimethyl-8,8-dipropyl-2-azaspiro [4.5] decane-2-propanamine dihydrochloride), caused a decrease in total serum cholesterol in dogs after oral administration. To determine whether an effect on cholesterol was common to this class of compounds, the immunomodulatory ...

Twelve normolipidic healthy human subjects were fed a diet with or without additional soybean phytosterols for 4 weeks in a crossover design. The order of the treatments was randomized. Phytosterols were added to the diet blended in butter. The dietary ratio cholesterol:phytosterols was 0.7 during the control period (436 mg ...

Dried flower of A. alliaceum when fed at 2% level in diet for 6 weeks to experimental rats rendered hypercholesterolemic by cholesterol feeding, exhibited blood cholesterol lowering effect. Cholesterol lowering efficacy of these garlic smelling flowers was similar to garlic oil fed at 0.002% level. Animals fed A. alliaceum flowers ...