Search results for "REDUCTASE"
showing 10 items of 798 documents
Remarkable quantitative and qualitative differences in HDL after niacin or fenofibrate therapy in type 2 diabetic patients
2014
Abstract HDL-increasing drugs such as fenofibrate and niacin have failed to decrease the cardiovascular risk in patients with type 2 diabetes. Drug-mediated quantitative and qualitative HDL modifications could be involved in these negative results. To evaluate the quantitative and qualitative effects of niacin and fenofibrate on HDL in patients with type 2 diabetes, a prospective, randomised controlled intervention trial was conducted. Thirty type 2 diabetic patients with low HDL were randomised to receive either fenofibrate (FFB) or niacin + laropiprant (ERN/LPR) as an add-on to simvastatin treatment for 12 weeks according to a crossover design. At the basal point and after each interventi…
Simvastatin Inhibits Inflammatory Properties ofStaphylococcus aureusα-Toxin
2002
Background—Simvastatin, a 3-hydroxy-methylglutaryl coenzyme A reductase inhibitor, has been shown to lower serum cholesterol levels in clinical use. Moreover, statins exert beneficial effects in vascular diseases by inhibition of leukocyte rolling, adherence, and transmigration. The aim of this study was to determine if pretreatment with simvastatin attenuatesStaphylococcus aureusα-toxin–induced increase in leukocyte-endothelial interactions during exotoxemia.Methods and Results—The effects of simvastatin on leukocyte-endothelial cell interactions were observed by intravital microscopy in the rat mesenteric microcirculation. Simvastatin (50 or 100 μg/kg) was administered 18 hours before the…
Lipid-altering efficacy of switching to ezetimibe/simvastatin 10/20 mg versus rosuvastatin 10 mg in high-risk patients with and without metabolic syn…
2011
Metabolic syndrome (MetS) is a clustering of atherosclerotic coronary heart disease risk factors. This post-hoc analysis compared the effects of switching to ezetimibe/simvastatin 10/20 mg or rosuvastatin 10 mg in a cohort of 618 high-risk hypercholesterolaemic patients with ( n=368) and without ( n=217) MetS who had previously been on statin monotherapy. Patients were randomised 1:1 to double-blind ezetimibe/simvastatin 10/20 mg or rosuvastatin 10 mg for 6 weeks. Least squares mean percent change from baseline and 95% confidence intervals in lipid efficacy parameters were calculated for the population and within subgroups. Treatment with ezetimibe/simvastatin was significantly more effect…
Effects of the flavonol quercetin on the bioavailability of simvastatin in pigs
2009
The influence of the dietary flavonol quercetin on the pharmacokinetics of the HMG-CoA reductase inhibitor simvastatin was investigated in pigs. Simvastatin (0.25mg/kg body weight) was orally administered to six pigs either without or with quercetin (10mg/kg). In addition, simvastatin was administered to three pigs that had received a diet supplemented with the flavonol over a period of 1 week. Daily quercetin intake was 10mg/kg in these animals. Co-ingestion of quercetin with the statin did not alter area under the concentration time curve (AUC(0-->infinity)), time to achieve maximum plasma concentration (t(max)) or half-life (t(1/2)) of simvastatin. However, there was a trend towards a re…
Switching from statin monotherapy to ezetimibe/simvastatin or rosuvastatin modifies the relationships between apolipoprotein B, LDL cholesterol, and …
2011
OBJECTIVE: To evaluate relationships between apolipoprotein B (Apo B), LDL cholesterol (LDL-C), and non-HDL-C in high-risk patients treated with lipid-lowering therapy. DESIGN AND METHODS: This post-hoc analysis calculated LDL-C and non-HDL-C levels corresponding to an Apo B of 0.9 g/L following treatment with 1) statin monotherapy (baseline) and 2) ezetimibe/simvastatin 10/20mg or rosuvastatin 10mg (study end). The percentages of patients reaching LDL-C, non-HDL-C, and Apo B targets were calculated at study end. RESULTS: After switching to ezetimibe/simvastatin or rosuvastatin, the LDL-C and non-HDL-C corresponding to Apo B=0.9 g/L were closer to the more aggressive LDL-C and non-HDL-C goa…
Differential proto-oncogene mRNA induction from rats treated with peroxisome proliferators
1990
After experimental treatment of rats with clofibrate or ciprofibrate, two peroxisomes proliferators with hypolipidemic activity, RNAs were prepared from liver, kidney, heart and brain; hybridization was done with DNA probes for c-myc and c-Ha-ras oncogenes and for cyanide insensitive Acyl CoA oxidase, a peroxisomal protein. c-myc mRNA is highly abundant in liver and at a lower extent in kidney, especially after treatment with ciprofibrate; clofibrate also allows a c-myc mRNA increase, but at a lower extent. c-Ha-ras, which is already expressed in all tested tissues from control animals, is stimulated by clofibrate and ciprofibrate treatments. Comparatively these compounds stimulate the cyan…
Vitamin K epoxide reductase activity in the metabolism of epoxides
1985
Abstract The importance of vitamine K epoxide reductase for the metabolism of a range of structurally diverse epoxides has been investigated. Vitamin K 1 epoxide is reduced by rat liver microsomes at a rate of 0.47 nmoles/g liver/min. The rate of menadione oxide reduction is not significantly higher than the non-enzymatic reduction rate. No measurable reduction of benzo[ a ]pyrene 4,5-oxide, benzo[ a ]pyrene 7,8-oxide, phenanthrene 9,10-oxide, styrene 7,8-oxide, and dieldrin has been detected, nor could trichothecene T-2 toxin inhibit reduction of vitamin K 1 epoxide. Thus, vitamin K epoxide reductase is very specific for vitamin K 1 epoxide. Taking into account the range of structurally di…
Enzymatic and pharmacokinetic studies on the metabolism of branched chain alpha-keto acids in the rat.
1983
Michaelis-constants and enzyme activities for dehydrogenation and transamination of the three branched chain alpha-keto acids in liver, kidney, skeletal muscle, and brain of rats are reported. After oral load only 11-22% of the keto acids pass the liver unchanged. Blood levels in pharmacokinetic and absorption studies are related to the Michaelis-constants. At the low keto-acid concentrations after oral application, dehydrogenation in the non-hepatic tissues is supposed to prevail over transamination. Data on feed efficiency of branched chain alpha-keto acids reported in the literature support this view. The chance for transamination is better after intravenous administration. The transfera…
Studies of the expression of the cytochrome P450IA, P450IIB, and P450IIC gene family in extrahepatic and hepatic tissues.
1990
We have studied the expression of three P-450 gene subfamilies in hepatic and extrahepatic tissues using the sensitive RNAse A protection assay. Members of the P450IA subfamily, which encodes the major methylcholanthrene-inducible cytochromes P-450, were found to be not expressed in extrahepatic tissues of untreated animals, raising the question whether these P-450 play a role in the metabolism of carcinogens in unexposed individuals. In contrast, members of the P450IIB family, some of which encode the major phenobarbital-inducible cytochromes P-450, were found to be expressed in some extrahepatic tissues of untreated rats and here most notably in the lung and in sebaceous glands. Members o…
Nitric oxide synthase-immunoreactive vagal afferent fibers in rat superior cervical ganglia
1995
Abstract Chronic (5–14 days) preganglionic denervation of the rat superior cervical ganglia by sectioning the cervical sympathetic trunk resulted in a time-related partial or complete loss of nitric oxide synthase (isoform I)-immunoreactive fibers and terminals surrounding many sympathetic ganglionic neurons. Unexpectedly, denervation unmasked many varicose nitric oxide synthase-immunoreactive fibers, some of which could be traced the entire length of the superior cervical ganglia. Injection of the retrograde tracer Fluorogold into the superior cervical ganglia labeled a population of nodose ganglion cells and of dorsal root ganglion cells from C8 to T3 segments. When the same sections were…