Search results for "pero"

Involvement of Oxysterols and Lysophosphatidylcholine in the Oxidized LDL–Induced Impairment of Serum Albumin Synthesis by HEPG2 Cells

2000

Abstract —Oxidized low density lipoproteins (Ox-LDLs) are increasingly thought to be a key element in atherogenesis. We have previously reported that serum albumin has important antioxidant properties and that a reduced synthesis of albumin may represent a crucial point in the overall antioxidant defense. In the present work, we aimed at determining whether Ox-LDL could modulate albumin synthesis in cultured human hepatocytes (HepG2 cells). With the use of enzyme immunoassay and radiolabeled leucine incorporation followed by specific immunoprecipitation, Ox-LDL was found to lead to a dose-dependent decrease in albumin secretion. Moreover, the protein synthesis and mRNA levels were decrease…

Short term treatment by fenofibrate enhances oxidative activities towards longchain fatty acids in the liver of lean zucker rats

1990

Lean Zucker rats were dosed orally for 1 week with fenofibrate (100 mg/kg/day). Liver weights of treated rats, expressed as per cent of body weight, were increased, while protein, DNA and triacylglycerol contents were not changed to any great extent per gram of liver, but increased when expressed per whole liver. Compared with the control animals, activities of fatty acid oxidase, of the peroxisomal fatty acid-oxidizing system and of catalase were markedly enhanced by fenofibrate, both per gram of liver and per total liver, while urate oxidase activity was slightly depressed when expressed per gram of liver. The activity of cytochrome c oxidase used as a mitochondrial marker was only higher…

Histamine up-regulates phosphodiesterase 4 activity and reduces prostaglandin E2-inhibitory effects in human neutrophils.

2000

Objective: To investigate whether histamine produces up-regulation of phosphodiesterase (PDE) activity with functional consequences in human peripheral blood neutrophils.¶Methods: PDE activity was studied by a radioisotopic method following anion-exchange chromatography. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used for detection of mRNA transcripts of PDE4 subtypes. Cyclic AMP (cAMP) levels were measured by enzyme-immunoassay, and superoxide generation by cytochrome c reduction.¶Treatment: Neutrophils were incubated for 4 h with histamine (1 μM).¶Results: PDE4 was the only isoenzyme activity increased in treated neutrophils. Kinetic analysis showed a ∼1.5-fold increase …

Sox17 regulates liver lipid metabolism and adaptation to fasting.

2014

Liver is a major regulator of lipid metabolism and adaptation to fasting, a process involving PPARalpha activation. We recently showed that the Vnn1 gene is a PPARalpha target gene in liver and that release of the Vanin-1 pantetheinase in serum is a biomarker of PPARalpha activation. Here we set up a screen to identify new regulators of adaptation to fasting using the serum Vanin-1 as a marker of PPARalpha activation. Mutagenized mice were screened for low serum Vanin-1 expression. Functional interactions with PPARalpha were investigated by combining transcriptomic, biochemical and metabolic approaches. We characterized a new mutant mouse in which hepatic and serum expression of Vanin-1 is …

Progestogens stimulate prostacyclin production by human endothelial cells.

2005

BACKGROUND: The effects of progestogens on endothelial physiology are poorly studied. Prostacyclin is a potent vasodilator synthesized by two isoforms of cyclooxygenase (COX) in endothelium. We examined the effects of two clinically used progestogens, progesterone and medroxyprogesterone acetate (MPA), on prostacyclin production by cultured human umbilical vein endothelial cells (HUVEC) and the possible role of progesterone receptors and both COX enzymes. METHODS: Cells were exposed to 1-100 nmol/l of either progesterone or MPA and prostacyclin production was measured in culture medium. RESULTS: Both progestogens significantly increased prostacyclin release in a time- and dose-dependent man…

A targeted apoB38.9 mutation in mice is associated with reduced hepatic cholesterol synthesis and enhanced lipid peroxidation.

2006

Familial hypobetalipoproteinemia (FHBL) due to truncation-specifying mutations of apolipoprotein B (apoB), which impair hepatic lipid export in very low-density lipoprotein (VLDL) particles, is associated with fatty liver. In an FHBL-like mouse with the apoB38.9 mutation, fatty liver develops despite reduced hepatic fatty acid synthesis. However, hepatic cholesterol contents in apoB38.9 mice are normal. We found that cholesterogenic enzymes (3-hydroxy-3-methylglutaryl-coenzyme A reductase, sterol-C5-desaturase, and 7-dehydrocholesterol reductase) were consistently downregulated in two separate expression-profiling experiments using a total of 19 mice ( n = 7 each for apob+/+and apob+/38.9, …

Is oxidative stress a therapeutic target in cardiovascular disease?

2010

An abnormal production of reactive oxygen species (ROS) and the subsequent decrease in vascular bioavailability of nitric oxide (NO) have long been proposed to be the common pathogenetic mechanism of the endothelial dysfunction, resulting from diverse cardiovascular risk factors such as hypercholesterolaemia, diabetes mellitus, chronic smoking, metabolic syndrome, and hypertension. Superoxide produced by the nicotinamide dinucleotide phosphate (NADPH) oxidase, mitochondrial sources, or the xanthine oxidase may react with NO, thereby resulting in excessive formation of peroxynitrite, a reactive nitrogen species that has been demonstrated to accelerate the atherosclerotic process by causing d…

417 SOLUBLE CELLULAR ADHESION MOLECULES, MYELOPEROXIDASE, AND NEOPTERIN IN METABOLIC SYNDROME PATIENTS WITH STABLE AND UNSTABLE ANGINA PECTORIS

2011

Interrelationships between oxidative stress and MMP-9 in subjects with severe obstructive sleep apnea syndrome

2016

Obstructive sleep apnea syndrome (OSAS) is significantly and independently associated with an increased risk of cardiovascular diseases, cerebrovascular events and all-cause mortality and some studies have demonstrated that the incidence of cardiovascular events is related to its severity. Our aim was to examine the oxidative status and the matrix metalloproteases (MMP) profile in a group of subjects with OSAS. We enrolled 48 subjects with OSAS, defined after a 1-night cardiorespiratory sleep study, which were subsequently subdivided in two subgroups according to the severity of OSAS: mild-moderate OSAS = “Low”, severe OSAS = “High”. We measured the parameters of oxidative stress, such as l…

In vitro evaluation of the efficacy of two bleaching procedures

2010

Objective: In vitro comparison of the efficacy of two bleaching procedures, one based on carbamide peroxide (CP) and the other on hydrogen peroxide (HP), simulating clinical conditions. Study Design: Two groups of 20 teeth in each group were selected. Group A: 22% CP, one hour a day for 21 consecutive days. Group B: 37.5% HP, in 2 treatment sessions with an one week interval between each session. At each session the product was applied three successive times for eight minutes. Colour was recorded before treatment, when it was finished and one week after finishing it, with the Vita EasyShade spectrophotometer. CIEL*a*b* and ΔE were established at each moment in the study. Intra-group data wa…