The influence of the cholesterol and protein diet on the mixed-function oxidases system activity and desaturation of fatty acids were examined. The phenobarbital innducibility of these parameters was analyzed too. Investigations were carried out on Wistar adult male rats. The animals were on the cholesterol (0.25%) and protein diet (32%) ...

Tincture of Crataegus, (TCR), is a hypocholesterolemic and antiatherosclerotic drug made from berries of hawthorn, Crataegus oxyacantha. Its main constituents are flavonoids, triterpene saponins and a few cardioactive amines. TCR, when administered simultaneously to rats fed an atherogenic diet, significantly increased the binding of 125I-LDL to the liver plasma membranes, ...

Effects of dietary protein on oxidized cholesterol-induced alterations in linoleic acid and cholesterol metabolism were studied in 4-wk-old male Sprague-Dawley rats, using casein and soybean protein as dietary protein sources. The rats were fed one of the two proteins in cholesterol-free, 0.3% cholesterol or 0.3% oxidized cholesterol mixture diets using ...

BACKGROUND & AIMS: Alterations of hepatic cholesterol metabolism in patients with cholesterol gallstones are still controversial. This study investigated whether hepatic cholesterol metabolism is altered in Japanese patients with cholesterol gallstones. METHODS: In this systematic study of 24 middle-aged nonobese and nondiabetic Japanese patients who had cholesterol gallstones and were ...

BACKGROUND & AIMS: The small intestine plays an important role in cholesterol homeostasis. The aim of this study was to examine the regulation of cholesterol synthesis by lysophosphatidylcholine in intestinal cells. METHODS: CaCo-2 cells cultured on semipermeable supports were incubated with taurocholate and lysophosphatidylcholine, and cholesterol synthesis rate, 3-hydroxy-3-methylglutaryl-coenzyme A ...

Male albino rats when treated with antimicrobial cotrimoxazole (trimethoprim+sulphamethaoxazole) showed an elevation of plasma high density lipoprotein (HDL) cholesterol and lecithin cholesterol acyl transferase activity (LCAT). Very low density lipoprotein and low density lipoprotein (VLDL+S4, 5LDL) cholesterol levels were decreased. However, total blood cholesterol and aortic cholesterol levels were normal. ...

Early responses of cholesterol metabolism to dietary cholesterol were compared between exogenous hypercholesterolemic (ExHC) and Sprague-Dawley rats. Both strains had a similar radioactivity of [14C]cholesterol in the serum half a day after the oral administration, but thereafter the radioactivity disappeared slowly in ExHC rats. ExHC rats promptly altered in response ...

RP 64477 (N-butyl-3-(p-decyloxybenzamido)-4-(methylthio)benzamide) has been shown to be a potent inhibitor of the cholesterol esterifying enzyme Acyl-coenzyme A:cholesterol O-acyltransferase (EC 2.3.1.26; ACAT) in intestinal, hepatic, adrenal, and arterial tissue preparations obtained from a range of animal species. Drug concentrations producing 50% inhibition of enzyme activity (IC50 values) ranged from 14-283 ...

Oral contraceptives (OC) have been shown to enhance the risk of atherosclerosis. In the present study we sought to determine which component of the OC (containing 0.067 mg estrogen and 0.667 mg of progestin) counts for alteration in lipids profile. Female rats were administered with 0.067 mg of 17 beta-estradiol ...

Endotoxin (LPS) and cytokines increase cholesterol synthesis and the secretion of lipoproteins by the liver in rodents resulting in hypercholesterolemia. Cholesterol 7 alpha-hydroxylase (CAH) is the rate-limiting enzyme in the conversion of cholesterol to bile acids in the liver, the major regulated pathway by which cholesterol is eliminated from the ...

The potent hypolipidemic activity of HOE 402 (4-amino-2-(4, 4-dimethyl-2-oxo-1-imidazolidinyl)pyrimidine-5-N-(trifluoromethyl-phenyl ) carboxamide monohydrochloride), which was previously demonstrated in rat and rabbit, was investigated in noncholesterol and cholesterol fed male hamsters. In normolipidemic hamsters fed a low cholesterol chow diet containing 0.10% or 0.15% HOE 402 for 3 weeks, the plasma total ...

We evaluated the effect of dietary cholesterol and oxidized cholesterol on the promotion of aberrant crypt foci (ACF), which are putative precancerous lesions in the colon. Sixty female C57BL/6J mice were given four weekly injections (ip) of azoxymethane (AOM) then fed either a control AIN-76 diet or the control diet ...

Within the cholesterol biosynthesis cascade, the enzyme 2,3-oxidosqualene cyclase [EC 5.4.99.7] is of special interest due to its dual function: cyclization of 2,3-monoepoxysqualene to lanosterol and 2,3;22,23-diepoxysqualene to oxylanosterol. Further determination of the significance of this enzyme for the intracellular cholesterol homeostasis was done with BIBX 79, a new potent, ...

The effects of dietary cholesterol and oxidized cholesterol on mammary tumor development were examined in female Sprague-Dawley rats exposed to the carcinogen N-methyl-N-nitrosourea (MNU). Animals were administered 50 mg/kg MNU at 50 days of age and fed either a control (AIN-76) diet or the control diet supplemented with 0.3% cholesterol ...

The boronated nucleosides with varying bases and sugar moieties were shown to be potent hypolipidemic agents in rodents. The 3'- aminocynaoborane dideoxythymidine derivative caused reductions in serum cholesterol and triglyceride levels, tissue lipids, VLDL and LDL cholesterol levels while elevating HDL cholesterol levels in rodents. The agents suppressed rat hepatic ...

Quantitative data on cholesterol movements in mucosa cell as a function of its localization in the small intestine have been obtained in normocholesterolemic (SW) or genetically hypercholesterolemic (RICO) rats. Bile cholesterol absorption is greater and more proximal than dietary cholesterol absorption, both taking place mainly in the top cells of ...

This study determined the effect of dietary (dipalmitoyl) triacylglycerol (TAG) structure on the absorption and metabolism of fat in the presence or absence of cholesterol. Sprague-Dawley male rats weighing approximately 180 g were fed diets containing 10 g/100 g diet 1,3-dipalmitoyl-2-oleoyl-glycerol-rich oil (POP) or 1(3),2-dipalmitoyl-3(1)-oleoyl-glycerol-rich oil (PPO), either with or ...

Incorporation of 13C from a dietary precursor into cholesterol was studied in neonatal rats. Rats were given uniformly 13C-enriched polyunsaturated fatty acids intragastrically and total lipid extracts of liver and brain were analyzed by 13C-NMR 1, 4, 8, and 15 days later. 13C-enrichment was detected in brain but not in ...

The present study analyses the effects of simvastatin, a specific inhibitor of the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA reductase) in male Syrian hamsters fed a standard diet or a diet supplemented with 0.12% cholesterol and 20% coconut oil. In hamsters fed the standard diet, gastric administration of simvastatin (10 mg/kg/day) during 12 ...

The mechanism of the hypocholesterolemic action of N-[4-(2-chlorophenyl)-6,7-dimethyl-3-quinolyl]-N'-(2, 4-difluorophenyl) urea (TMP-153), a potent acyl-CoA:cholesterol acyltransferase (ACAT) inhibitor, was studies in Golden hamsters. TMP-153 (0.5-1.5 mg/kg) dose-dependently reduced plasma total- and low density lipoprotein (LDL)-cholesterol without affecting high density lipoprotein (HDL)-cholesterol. TMP-153 markedly reduced the cholesterol influx into the plasma upon ...

The effects of dietary oleic acid on cholesterol metabolism were investigated and compared with those of palmitic acid in hamsters. Addition of 5% oleic acid to a 0.1% cholesterol-supplemented diet decreased plasma total cholesterol, very low density lipoprotein (VLDL) cholesterol, and low density lipoprotein (LDL) cholesterol, increased hepatic LDL receptor ...

BACKGROUND & AIMS: The Smith-Lemli-Opitz syndrome is a recessive inherited disorder characterized by neurological developmental defects and dysmorphic features with a defect in cholesterol synthesis at the conversion of 7-dehydrocholesterol to cholesterol. BM 15.766 inhibits 7-dehydrocholesterol-delta 7-reductase and reproduces the biochemical defect. The aim of this study was to investigate ...

The degree of serum cholesterol lowering by up to almost maximal inhibition of cholesterol absorption was tested during neomycin and neomycin + sitostanol treatment in six hypercholesterolemic men. Neomycin decreased cholesterol absorption efficiency by 49% and the combination by 79%, and serum cholesterol level by 27% and 36%, respectively. The ...

Three lines of Japanese quail males, unselected controls (CL), high response (HL), and low response (LL) lines, selected for plasma total cholesterol for 18 generations, were fed all-plant source, nonatherogenic diets to which 0 or .5% cholesterol were added from 6 to 18 wk of age. Atherosclerotic scores (AS) of ...

Acyl CoA:cholesterol acyltransferase (EC2.3.1.26, ACAT), responsible for intracellular esterification of cholesterol, may play an important role in cholesterol trafficking within the cell, and thus, in maintenance of cellular cholesterol homeostasis. Bile acids are potential regulators of cholesterol trafficking in the liver. Therefore, the effect of bile salts on hepatic ACAT ...

Abundant data from both experimental animals and humans now support the conclusion that the incidence of atherosclerosis is related to the concentration of plasma cholesterol. Cholesterol homeostasis in the body is maintained by regulatory mechanisms, which control the input and output processes. The liver plays a key role in cholesterol ...

The effects of misoprostol (cytotec, SC29333) on circulating lipoproteins and liver microsomal enzyme activity were studied. Misoprostol increased serum levels of high density lipoprotein-cholesterol and decreased total cholesterol and triglycerides. The high density lipoprotein-cholesterol/total cholesterol ratio increased by 54.8%. In parallel, misoprostol significantly altered enzyme hepatic activity. Liver microsomal cytochromes ...

The diurnal rhythm of cholesterol synthesis was determined by deuterium incorporation from body water in five normolipemic men studied during a 24-h baseline period and on the 1st, 2nd, and 4th days of a simulated 12-h time zone shift achieved by delaying sleep times and, starting on the 2nd day, ...

In the present study, we investigated the hypocholesterolemic effect of F-1394 ((1s,2s)-2-[3-(2,2-dimethylpropyl)-3-nonylureido]aminocycloh exane-1-yl 3-[N-(2,2,5,5-tetramethyl-1,3-dioxane-4-carbonyl)amino] propionate), a potent and selective inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), and the effect on cholesterol absorption via the gut in rats fed a 1% cholesterol diet. Single administration of F-1394 to the cholesterol diet-fed rats at ...

Amylase-resistant starch (RS) represents a substrate for the bacterial flora of the colon, and the question arises as whether RS shares with soluble fibers common mechanisms for their lipid-lowering effects. It is uncertain whether a cholesterol-lowering effect depends basically on an enhanced rate of steroid excretion or whether colonic fermentations ...

Agents that inhibit hepatic cholesterol biosynthesis reduce circulating cholesterol levels in experimental animals and humans, and may be of pharmacological importance in the prevention of atherosclerosis. Azalanstat (RS-21607), a synthetic imidazole, has been shown to inhibit cholesterol synthesis in HepG2 cells, human fibroblasts, hamster hepatocytes and hamster liver, by inhibiting ...

Clinical interventions that accelerate conversion of cholesterol to bile acids reduce circulating low density lipoprotein (LDL) cholesterol concentrations. The initial and rate-limiting step in the bile acid biosynthetic pathway is catalyzed by hepatic cholesterol 7 alpha-hydroxylase. To examine the effects of transient primary overexpression of this enzyme on sterol metabolism ...

Three lines of Japanese quail females, randombred controls (CL), high response (HL), and low response (LL) lines, selected for plasma total cholesterol for 18 generations, were fed all-plant-source, nonatherogenic diets to which 0 or .5% cholesterol were added from 6 to 18 wk of age. In all three lines, plasma ...

Propionate is a short-chain fatty acid formed in the colon and supposedly involved in the cholesterol-lowering effect of soluble fibre. To explore the underlying mechanism(s) of this fibre action, we have used human hepatocytes in primary culture to study the effects of propionate on hepatic lipid synthesis. Initial experiments with ...

Hepatic activities of rate limiting enzymes in fatty acid and cholesterol synthesis and cholesterol degradation were determined in lean and obese LA/N-cp rats. The hepatic activities of acetyl-CoA carboxylase and fatty acid synthetase, the key enzymes of fatty acid synthesis and 3-hydroxy-3-methylglutaryl coenzyme A reductase (the rate limiting enzyme in ...

A concept proposed by Berg (Berg, K. 1989. Arteriosclerosis. 9: I-50-I-58) is that a combination of level and variability genes determine an individual's overall plasma lipid levels and atherosclerotic risk. Our goal was to determine which inbred mouse strains could be used to identify candidate level and variability genes controlling ...

Regulation of the activity of lanosterol 14 alpha-demethylase (cytochrome P-45014DM) by dietary cholesterol was studied in rats. In male rats fed a 3% cholesterol diet for 1 and 4 weeks, the activity of 24,25-dihydrolanosterol 14 alpha-demethylase was decreased in the liver. The cytochrome P-45014DM protein content detected by immunoblotting was ...

Interruption of enterohepatic circulation (EHC) of bile salts in several species is known to cause a significant decrease in plasma concentrations of low density lipoprotein (LDL) cholesterol, but to have little effect on high density lipoprotein (HDL) cholesterol. The present study, for the first time, demonstrates that partial interruption of ...

The effect of dried oyster mushroom (Pleurotus ostreatus) on cholesterol (C) content in serum, in lipoproteins and in liver, and on the activity of 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase in liver microsomes, was studied in male rats (strain Wistar, initial body weight 75 g) fed on low-cholesterol (9 mg/100 g) and ...

We investigated the relationship between dietary highly hydrogenated soybean oil (HSO) and cholesterol transport in rats. In the first study, to examine the effects on cholesterol transport of different concentrations of HSO in dietary oil, rats were given one of the three diets containing 0, 25, or 50% HSO in ...

The in vivo total body cholesterol transport of homozygous apoE-deficient (-/-) and control (+/+) mice was evaluated by compartmental analysis of plasma cholesterol decay. Body cholesterol fractional catabolic rates of chow fed mutants were less (-/-, 0.17 +/- 0.02; +/+, 0.51 +/- 0.06 day-1) and body cholesterol contents greater (-/-, ...

Diet-cancer and diet-cardiovascular disease interrelationships may be explained by the mevalonate-suppressive action of isoprenoid end products of plant secondary metabolism. Assorted monoterpenes, sesquiterpenes, carotenoids and tocotrienols posttranscriptionally down regulate 3-hydroxy-3-methylglutaryl coenzyme A reductase activity, a key activity in the sterologenic pathway. The modest decrease in cholesterol synthesis is associated with ...

Previous studies with a number of selective acylcoenzyme A:cholesterol acyltransferase (ACAT) inhibitors in several animal models have demonstrated significant reductions in plasma cholesterol and, in some studies, triglyceride levels. This study was conducted to examine the effects of two ACAT inhibitors, CL 283,546 and CL 283,796, in cholesterol-high fat diet ...

The amount of cholesterol that circulates in the plasma as lipoproteins can be affected by the balance of cholesterol metabolism within and between the intestines and liver. In the present report, we describe a novel hypocholesterolemic agent and document its pharmacological effects in animal models of hypercholesterolemia. The oral administration ...

For three weeks, male Sprague-Dawley rats at either four weeks (young) or eight months (adult) of age were pair-fed one of the purified diets free of or containing either 0.2% of oxidized cholesterol mixture (cholesterol oxidation products) or 0.2% of cholesterol. Although the food intake was similar, dietary oxidized cholesterol ...

The effect of a probiotic composed of Bacillus, Lactobacillus, Streptococcus, Saccharomyces and Candida species (each at 10(7-8) colony-forming units (cfu)/g rice bran), given at a level of 150 g/kg diet for 6 weeks, on lipid metabolism was examined in the faeces, serum and liver of male rats. Liver weight decreased ...

The effects of the flower lipid-saccharide complex and unsaponifiable matter (1 g/kg of diet) from the sunflower on liver lipid metabolism and intestinal flora was studied in rats given cholesterol-enriched diets. After six weeks of feeding, the microsomal cholesterol concentration in the liver had been significantly reduced with the sunflower ...

A synthetic fat-free diet, previously shown to decrease hepatic cholesterol synthesis, was utilized to manipulate cholesterol balance in vivo in female Sprague-Dawley rats. A significant 65% decrease of hepatic cholesterol synthesis compared to controls was shown after 1 week of treatment, which remained constant during the following 3 weeks. The ...

Bezafibrate is a hypolipidemic fibric acid derivative known to induce cholesterol supersaturation of bile. To characterize its effects on hepatic cholesterol metabolism, 31 normolipidemic, normal-weight patients with gallstones undergoing cholecystectomy were studied. Eleven patients (5 men) were randomized to treatment with bezafibrate, 200 mg three times daily for 4 weeks ...

Prospects for therapy for hyperlipoproteinaemia are likely to rely more heavily on improvement of known molecules than on development of new ones aimed at various components of the plasma lipid transport system. Promising advances are revealed in both directions. A new synthetic inhibitor of HMG CoA reductase, atorvastatin, lowers plasma ...