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On the mode of action of 3 phenylindole towards Aspergillus niger
3 Phenylindole is an antimicrobial compound active towards many fungi and gram positive bacteria. At 5 μg/ml it inhibits growth of Aspergillus niger. Higher concentrations (50 μg/ml) also suppress spore germination; they do not kill the fungus. Dry weight of the fungus still increases for 1 or 2 days after fungicide treatment. The toxicant has no effect on O2 uptake even at higher concentrations (100 μg/ml). The compound markedly affects composition of the lipid fraction of A. niger inducing a decrease in phospholipid concentration with a coincident increase in free fatty acids. Sterol pattern and sterol concentrations were not affected. Antifungal activity was reversed by phospholipids added to the medium. 3 Phenylindole induced a slight leakage of 32P labeled compounds from the treated cells under growth conditions but not under nongrowth conditions. A strain of A. niger resistant to 3 phenylindole had the same phospholipid and sterol pattern as the wild type, but the level of both components was higher (40-60%). The 3 phenylindole resistant strain showed resistance to triarimol and pimaricin. The wild type and the resistant strain both took up 3 phenylindole quite rapidly and accumulated it in the mycelium. 3 Phenylindole possibly interferes with phospholipid function in cell membranes, although the specific site of action has not yet been elucidated. Chemicals/CAS: ergosterol, 23637-22-1, 2418-45-3, 3992-98-1, 57-87-4
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[Abstract]
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2 |
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The effect of PPE-induced emphysema and chronic LPS-induced pulmonary inflammation on atherosclerosis development in APOE*3-LEIDEN mice
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2013
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Author: |
Khedoe, P.P.S.J.
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Wong, M.C.
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Wagenaar, G.T.M.
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Plomp, J.J.
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Eck, M. van
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Havekes, L.M.
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Rensen, P.C.N.
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Hiemstra, P.S.
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Berbée, J.F.P.
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Keywords: |
Biology · Apolipoprotein E3 · Blood clotting factor 5 Leiden · Cholesterol · Interleukin 6 · Lipopolysaccharide · Pancreatic elastase · Phospholipid · Triacylglycerol · Animal experiment · Animal model · Animal tissue · Atherosclerosis · Cardiovascular disease · Cholesterol blood level · Chronic inflammation · Controlled study Ccytokine release · Hyperlipidemia · Lung emphysema · Macrophage · Mouse · Neutrophil · Nonhuman · Phospholipid blood level · Pneumonia · Triacylglycerol blood level · Biomedical Innovation · Healthy Living · Life · MHR - Metabolic Health Research · EELS - Earth, Environmental and Life Sciences
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Background: Chronic obstructive pulmonary disease (COPD) is characterized by pulmonary inflammation, airways obstruction and emphysema, and is a risk factor for cardiovascular disease (CVD). However, the contribution of these individual COPD components to this increased risk is unknown. Therefore, the aim of this study was to determine the contribution of emphysema in the presence or absence of pulmonary inflammation to the increased risk of CVD, using a mouse model for atherosclerosis. Because smoke is a known risk factor for both COPD and CVD, emphysema was induced by intratracheal instillation of porcine pancreatic elastase (PPE). Methods: Hyperlipidemic APOE*3-Leiden mice were intratracheally instilled with vehicle, 15 or 30 mg PPE and after 4 weeks, mice received a Western-type diet (WTD). To study the effect of emphysema combined with pulmonary inflammation on atherosclerosis, mice received 30 mg PPE and during WTD feeding, mice were intranasally instilled with vehicle or low-dose lipopolysaccharide (LPS; 1 mg/mouse, twice weekly). After 20 weeks WTD, mice were sacrificed and emphysema, pulmonary inflammation and atherosclerosis were analysed. Results: Intratracheal PPE administration resulted in a dose-dependent increase in emphysema, whereas atherosclerotic lesion area was not affected by PPE treatment. Additional low-dose intranasal LPS administration induced a low-grade systemic IL-6 response, as compared to vehicle. Combining intratracheal PPE with intranasal LPS instillation significantly increased the number of pulmonary macrophages and neutrophils. Plasma lipids during the study were not different. LPS instillation caused a limited, but significant increase in the atherosclerotic lesion area. This increase was not further enhanced by PPE. Conclusion: This study shows for the first time that PPE-induced emphysema both in the presence and absence of pulmonary inflammation does not affect atherosclerotic lesion development. © 2013 Khedoe et al.
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[PDF]
[Abstract]
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3 |
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13-week oral toxicity study with stanol esters in rats
Plant sterols and their saturated derivatives, known as stanols, reduce serum cholesterol when consumed in amounts of approximately 2 g per day. Stanol fatty acid esters have been developed as a highly fat-soluble form that may lower cholesterol more effectively than stanols. Stanol esters occur naturally in human diets, but at levels far below those known to lower cholesterol. The present study was conducted to assess the safety of stanol esters upon subchronic ingestion at levels comparable to or exceeding those recommended for lowering cholesterol. Two stanol fatty acid ester preparations, wood-derived stanol esters and vegetable oil-derived stanol esters, were fed to groups of 20 male and 20 female Wistar rats for 13 weeks, at dietary concentrations of 0, 0.2, 1, and 5% total stanols (equivalent to 0, 0.34, 1.68, and 8.39% wood-derived stanol esters and 0, 0.36, 1.78, and 8.91% vegetable oil-derived stanol esters). Both preparations were well tolerated as evidenced by the absence of clinical changes or major abnormalities in growth, food and water consumption, ophthalmoscopic findings, routine hematological and clinical chemistry values, renal concentrating ability, composition of the urine, appearance of the feces, estrus cycle length, organ weights, gross necropsy findings, and histopathological findings. Plasma cholesterol and phospholipids were slightly decreased in males fed the stanol esters. In both sexes, plasma levels of plant sterols were decreased whereas those of stanols tended to increase. Fecal excretion of sterols, including cholesterol, and stanols was markedly increased in the stanol ester groups. Compared to controls, male rats fed stanol esters showed somewhat lower liver weights and more pronounced glycogen depletion. These hepatic changes were considered to reflect an altered nutritional condition and not a pathological condition. Plasma levels of vitamin E, vitamin K1, and, to a lesser extent, vitamin D were decreased in males and females fed the high-dose diets. Hepatic levels of vitamins E and D showed similar changes (vitamin K1 in the liver was not determined). For both preparations, the mid-dose level (1% total stanols in the diet) was a no-observed-adverse-effect level. This dietary level provided approximately 0.5 g total stanols/kg body wt/day.
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[Abstract]
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4 |
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Adenovirus mediated overexpression of human phospholipid transfer protein alters plasma HDL levels in mice
article |
1998
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Author: |
Ehnholm, S.
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Dijk, K.W. van
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Hof, B. van
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Zee, A.D. van
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Olkkonen, V.M.
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Jauhiainen, M.
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Hofker, M.
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Havekes, L.
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Ehnholm, C.
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Keywords: |
Biology · Apolipoprotein A-I · HDL conversion · HDL metabolism · Lipid metabolism · Phospholipid transfer protein · Recombinant adenovirus · Adenoviridae · Animals · Apolipoprotein A-I · Carrier Proteins · Cholesterol · Cholesterol Esters · Female · Genetic Vectors · Humans · Lipoproteins · Lipoproteins, HDL · Liver · Membrane Proteins · Mice · Mice, Inbred C57BL · Mice, Transgenic · Phospholipid Transfer Proteins · Phospholipids · Recombinant Proteins · Triglycerides
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To study the function of plasma phospholipid transfer protein (PLTP) in vivo, a liver directed adenoviral gene transfer system was used to overexpress human PLTP in mice. For the experiments, two strains of mice, wild type (C57/B1) and mice transgenic for the human apoA-I gene (HuApoA- ITg), were utilized. Five days after injection of the recombinant PLTP adenovirus, wild type mice showed a 4-fold increase in serum PLTP activity in (12.2 ± 1.3 μmol/ml/per h to 48.1 ± 8.6 μmol/ml per h (+394%), P < 0.001). The PLTP overexpression induced significant reduction of serum cholesterol (2.46 ± 0.08 to 0.69 ± 0.42 mmol/l (-72%), P < 0.001), phospholipids (3.10 ± 0.06 to 0.90 ± 0.24 mmol/l (-71%), P < 0.01), and triglycerides (0.2 ± 0.07 to 0.08 ± 0.03 mmol/l (-69%), (P < 0.001). ApoA- I was hardly detectable in the serum. These lipid changes were due to a dramatic reduction of high density lipoprotein (HDL). The HuApoA-ITg mice displayed higher basal HDL level and PLTP activity. Adenovirus mediated PLTP overexpression in these mice resulted in a similar decrease of the lipid levels as that seen in the C57/Bl mice. However, the lipoprotein profile revealed a redistribution of HDL, with the appearance of larger buoyant HDL species. The results demonstrate that plasma phospholipid transfer protein in vivo causes high density lipoprotein (HDL) conversion and thereby plays a central role in HDL metabolism.
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[PDF]
[Abstract]
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5 |
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Increased fecal bile acid excretion in transgenic mice with elevated expression of human phospholipid transfer protein
Objective - HDL plays a key role in protection against development of atherosclerosis by promoting reverse cholesterol transport from peripheral tissues to the liver for secretion into bile. Phospholipid transfer protein (PLTP) promotes the transfer of phospholipids between lipoproteins and modulates HDL size and composition, thereby having a crucial role in HDL metabolism. We investigated the effect of increased PLTP activity on removal of cholesterol from the body. Methods and Results - On a chow diet, transgenic mice overexpressing human PLTP have a 15-fold increased plasma PLTP activity compared with wild-type mice (572.4±59.2 versus 38.6±3.6 μmol/mL per h). Plasma cholesterol, mainly present in HDL, is strongly decreased (-92%), caused by a rapid clearance from the circulation by the liver and leading to a 1.8-fold increase in hepatic cholesteryl esters. This results in a 2-fold increase in biliary bile acid secretion without changing the bile saturation index. Consequently, the transgenic mice show a 1.4-fold increase in the amount of excreted fecal bile acids compared with wild-type mice, whereas fecal neutral sterol excretion is unchanged. Conclusions - Our data show that elevation of PLTP activity results in rapid disposal of cholesterol from the body via increased conversion into bile acids and subsequent excretion. Chemicals/CAS: Bile Acids and Salts; Carrier Proteins; Cholesterol, 57-88-5; Cholesterol, HDL; Lipase, EC 3.1.1.3; Lipoprotein Lipase, EC 3.1.1.34; Membrane Proteins; Phospholipid Transfer Proteins; Sterols
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[Abstract]
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6 |
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Cholesterol 7α-hydroxylase deficiency in mice on an APOE*3-Leiden background increases hepatic ABCA1 mRNA expression and HDL-cholesterol
article |
2006
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Author: |
Post, S.M.
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Groenendijk, M.
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Hoogt, C.C. van der
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Fievet, C.
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Luc, G.
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Hoekstra, M.
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Princen, H.M.G.
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Staels, B.
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Rensen, P.C.N.
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Keywords: |
Health · Biomedical Research · High-density lipoprotein · ABC transporter A1 · High density lipoprotein cholesterol · Intermediate density lipoprotein · Low density lipoprotein · Messenger RNA · Phosphatidylcholine sterol acyltransferase · Very low density lipoprotein · Bile acid · Phospholipid transfer protein · Phospholipid transfer protein, mouse · Animal experiment · Animal tissue · Bile acid synthesis · Biosynthesis · Catabolism · Cholesterol blood level · Cholesterol metabolism · cholesterol transport · Conhuman · Protein expression · Transgenic mouse · Genetics · Metabolism · Mouse · Mouse mutant · Physiology · Animals · Apolipoprotein E3 · ATP-Binding Cassette Transporters · Bile Acids and Salts · Cholesterol 7-alpha-Hydroxylase · Cholesterol, HDL · Female · Gene Expression Regulation · Gene Expression Regulation, Enzymologic · Humans · Liver · Mice · Mice, Knockout · Mice, Transgenic · Phosphatidylcholine-Sterol O-Acyltransferase · Phospholipid Transfer Proteins · RNA, Messenger
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OBJECTIVE - High-density lipoprotein (HDL) plays a key role in protection against development of atherosclerosis by reducing inflammation, protecting against LDL oxidation, and promoting reverse cholesterol transport from peripheral tissues to the liver for secretion into bile. Cholesterol 7α-hydroxylase (Cyp7a1) catalyzes the rate-limiting step in the intrahepatic conversion of cholesterol to bile acids that may have a role in HDL metabolism. We investigated the effect of Cyp7a1 deficiency on HDL metabolism in APOE*3-Leiden transgenic mice. METHODS AND RESULTS - Reduced bile acid biosynthesis in Cyp7a1-/-.APOE*3-Leiden mice versus APOE*3-Leiden mice did not affect total plasma cholesterol levels, but the distribution of cholesterol over various lipoproteins was different. Cholesterol was decreased in apoB-containing lipoproteins (ie, VLDL and IDL/LDL), whereas cholesterol was increased in HDL. The activity of PLTP and LCAT, which play a role in HDL catabolism, were not changed, and neither was HDL clearance. However, the hepatic cholesterol content was 2-fold increased, which was accompanied by a 2-fold elevated expression of hepatic ABCA1 and increased rate of cholesterol efflux from the liver to HDL. CONCLUSIONS - Strongly reduced bile acid synthesis in Cyp7a1-/-.APOE*3-Leiden mice leads to increased plasma HDL-cholesterol levels, as related to an increased hepatic expression of ABCA1. © 2006 American Heart Association, Inc. Chemicals / CAS: cholesterol 7alpha monooxygenase, 9037-53-0; phosphatidylcholine sterol acyltransferase, 9031-14-5; Apolipoprotein E3; ATP binding cassette transporter 1; ATP-Binding Cassette Transporters; Bile Acids and Salts; Cholesterol 7-alpha-Hydroxylase, EC 1.14.13.17; Cholesterol, HDL; Phosphatidylcholine-Sterol O-Acyltransferase, EC 2.3.1.43; phospholipid transfer protein, mouse; Phospholipid Transfer Proteins; RNA, Messenger
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[Abstract]
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7 |
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Insertion of pea lectin into a phospholipid monolayer
Pea lectin (PSL) is a secretory sugar-binding protein, readily soluble in aqueous solutions of low osmolarity. However, PSL also appears to be associated with the plasma membrane at the tip of young pea root hairs. By using the Wilhelmy plate method, we found that PSL can insert into a lipid monolayer. This property appeared to be independent of the sugar- binding ability of the protein. This result suggests that PSL may be directly involved in membrane-mediated interactions with saccharide ligands, for example during root hair infection by symbiotic rhizobia. Chemicals/CAS: Lectins; pea lectin; Phospholipids; Plant Lectins
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[Abstract]
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8 |
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Alkylphospholipids inhibit capillary-like endothelial tube formation in vitro: Antiangiogenic properties of a new class of antitumor agents
article |
2008
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Author: |
Zerp, S.F.
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Vink, S.R.
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Ruiter, G.A.
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Koolwijk, P.
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Peters, E.
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Luit, A.H. van der
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Jong, D.de
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Budde, M.
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Bartelink, H.
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Blitterswijk, W.J. van
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Verheij, M.
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Keywords: |
Health · Alkylphospholipids · Angiogenesis · Apoptosis · Endothelial cells · In Vitro · angiogenesis inhibitor · antineoplastic agent · collagen · edelfosine · fibrin · miltefosine · perifosine · phospholipid derivative · angiogenesis · antiangiogenic activity · antineoplastic activity · aorta · apoptosis · statistical significance · umbilical vein · vascular endothelium · Alkylation · Angiogenesis Inhibitors · Animals · Antineoplastic Agents · Apoptosis · Capillaries · Cattle · Cell Line, Tumor · Cells, Cultured · Dose-Response Relationship, Drug · Endothelial Cells · Endothelium, Vascular · Humans · Indicators and Reagents · Phosphodiesterase Inhibitors · Phospholipid Ethers · Phospholipids · Phosphorylcholine · Healthy for Life · Healthy Living
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Synthetic alkylphospholipids (APLs), such as edelfosine, miltefosine and perifosine, constitute a new class of antineoplastic compounds with various clinical applications. Here we have evaluated the antiangiogenic properties of APLs. The sensitivity of three types of vascular endothelial cells (ECs) (bovine aortic ECs, human umbilical vein ECs and human microvascular ECs) to APL-induced apoptosis was dependent on the proliferative status of these cells and correlated with the cellular drug incorporation. Although confluent, nondividing ECs failed to undergo apoptosis, proliferating ECs showed a 3-4-fold higher uptake and significant levels of apoptosis after APL treatment. These findings raised the question of whether APLs interfere with new blood vessel formation. To test the antiangiogenic properties in vitro, we studied the effect of APLs using two different experimental models. The first one tested the ability of human microvascular ECs to invade a three-dimensional human fibrin matrix and form capillary-like tubular networks. In the second model, bovine aortic ECs were grown in a collagen gel sandwich to allow tube formation. We found that all three APLs interfered with endothelial tube formation in a dose-dependent manner, with a more than 50% reduction at 25 μmol/l. Interference with the angiogenic process represents a novel mode of action of APLs and might significantly contribute to the antitumor effect of these compounds. © 2008 Lippincott Williams & Wilkins, Inc. Chemicals / CAS: collagen, 9007-34-5; edelfosine, 65492-82-2; fibrin, 9001-31-4; miltefosine, 58066-85-6; perifosine, 157716-52-4; Angiogenesis Inhibitors; Antineoplastic Agents; D 21266; edelfosine, 65492-82-2; Indicators and Reagents; Phosphodiesterase Inhibitors; Phospholipid Ethers; Phospholipids; Phosphorylcholine, 107-73-3
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[Abstract]
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9 |
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Maternal and neonatal plasma antioxidant levels in normal pregnancy, and the relationship with fatty acid unsaturation
During pregnancy, maternal plasma concentrations of the peroxidation-susceptible polyunsaturated fatty acids (polyenes) increase. In addition, the proportion of polyenes is higher in neonatal plasma than in maternal plasma. To study whether these increased amounts of polyenes affect antioxidant levels, we measured lipid-soluble antioxidants in maternal and neonatal plasmas obtained during thirty-five normal pregnancies. These values were then related to the degree of phospholipid-fatty acid unsaturation. Maternal plasma levels of tocopherols and lutein increased during pregnancy, as assessed at 14, 22, and 32 weeks of gestation. However, β-carotene levels decreased, and levels of other carotenoids remained unchanged. Retinol levels were only decreased at 32 weeks of gestation. The value for α-tocopherol:phospholipid-polyene unsaturation index (UI) also increased during pregnancy, despite the observed increase in UI. Corresponding ratios for several carotenoids and retinol, however, decreased during pregnancy. After delivery, maternal plasma levels of δ-tocopherol and β + γ-tocopherol, as well as β + γ-tocopherol:UI values, were lower than values at 32 weeks of gestation. Umbilical-cord plasma antioxidant levels and antioxidant:UI values, except retinol:UI, were significantly lower than maternal values. Significant and consistent cord v. maternal correlations were observed for plasma levels of β + γ-tocopherol, lutein and β-carotene, but not for δ-tocopherol, α-tocopherol, lycopene, α-carotene, and retinol. In conclusion, although during pregnancy maternal plasma tocopherol levels increased concurrently with, or more than, fatty acid unsaturation in plasma phospholipids, the decrease in carotenoid:UI values during gestation, the decrease in maternal plasma levels of δ-tocopherol and β + γ-tocopherol after delivery, and the low neonatal antioxidant levels merit further investigation.
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[PDF]
[Abstract]
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10 |
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Effect of Moderate Alcohol Consumption on Parameters of Reverse Cholesterol Transport in Postmenopausal Women
Background: Alcohol consumption is associated with increased high-density lipoprotein (HDL) cholesterol levels. One of the main antiatherogenic functions of HDL is reverse cholesterol transport. Three early steps of reverse cholesterol transport are (1) cellular cholesterol efflux, (2) plasma cholesterol esterification (EST), and (3) cholesteryl ester transfer (CET) to apolipoprotein B-containing lipoproteins. Our previous study in healthy middle-aged men showed that moderate alcohol consumption increases cellular cholesterol efflux and EST. This study investigated the effect of moderate alcohol consumption on three early steps of reverse cholesterol transport in postmenopausal women. Methods: In a randomized crossover study, 18 postmenopausal women-all apparently healthy, non-smoking, and moderate alcohol drinkers-consumed white wine or white grape juice with evening dinner during 2 successive periods of 3 weeks. During the white wine period, alcohol intake equaled 24 g/day. At the end of each of the two experimental periods, blood samples were collected. Results: Three weeks of alcohol consumption increased serum HDL cholesterol levels (5.0%; p < 0.05), serum HDL phospholipid levels (5.8%; p < 0.05), and the ex vivo cellular cholesterol efflux capacity of plasma, measured with Fu5AH cells (3.4%; p < 0.05). Plasma EST and CET did not change. Conclusions: Moderate alcohol intake increases serum HDL cholesterol level and stimulates cellular cholesterol efflux in postmenopausal women. Moderate alcohol consumption does not seem to affect two other early steps of reverse cholesterol transport at this level of alcohol intake. Our data suggest that the relative protection of moderate alcohol consumption against cardiovascular disease in postmenopausal women may involve the stimulation of reverse cholesterol transport through increased HDL.
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[Abstract]
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11 |
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Stimulation of lipogenesis by pharmacological activation of the liver X receptor leads to production of large, triglyceride-rich very low density lipoprotein particles
article |
2002
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Author: |
Grefhorst, A.
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Elzinga, B.M.
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Voshol, P.J.
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Plösch, T.
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Kok, T.
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Bloks, V.W.
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Sluijs, F.H. van der
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Havekes, L.M.
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Romijn, J.A.
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Verkade, H.J.
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Kuipers, F.
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Keywords: |
Animals · Anticholesteremic Agents · Apolipoproteins E · Carrier Proteins · Cell Line · DNA-Binding Proteins · Hypertriglyceridemia · Lipids · Lipoproteins, VLDL · Liver · Male · Membrane Proteins · Mice · Mice, Inbred C57BL · Phospholipid Transfer Proteins · Rats · Receptors, Cytoplasmic and Nuclear · Receptors, LDL · Receptors, Retinoic Acid · Receptors, Thyroid Hormone · Sulfonamides · Triglycerides · Animalia · Mus musculus
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The oxysterol-activated liver X receptor (LXR) provides a link between sterol and fatty acid metabolism; activation of LXR induces transcription of lipogenic genes. This study shows that induction of the lipogenic genes Srebp-1c, Fas, and Acc1 upon administration of the synthetic LXR agonist T0901317 to C57BL/6J mice (10 mg/kg/day, 4 days) is associated with massive hepatic steatosis along the entire liver lobule and a 2.5-fold increase in very low density lipoprotein-triglyceride (VLDL-TG) secretion. The increased VLDL-TG secretion was fully accounted for by formation of larger (129 ± 9 nm versus 94 ± 12 nm, a 2.5-fold increase of particle volume) TG-rich particles. Stimulation of VLDL-TG secretion did not lead to elevated plasma TG levels in C57BL/6J mice, indicating efficient particle metabolism and clearance. However, T0901317 treatment did lead to severe hypertriglyceridemia in mouse models of defective TG-rich lipoprotein clearance, i.e. APOE*3-Leiden transgenic mice (3.2-fold increase) and apoE-/-LDLr-/- double knockouts (12-fold increase). Incubation of rat hepatoma McA-RH7777 cells with T0901317 also resulted in intracellular TG accumulation and enhanced TG secretion. We conclude that, in addition to raising high density lipoprotein cholesterol concentrations, pharmacological LXR activation in mice leads to development of hepatic steatosis and secretion of atherogenic, large TG-rich VLDL particles. Chemicals/CAS: Anticholesteremic Agents; Apolipoproteins E; Carrier Proteins; DNA-Binding Proteins; Lipids; Lipoproteins, VLDL; liver X receptor; Membrane Proteins; Phospholipid Transfer Proteins; Receptors, Cytoplasmic and Nuclear; Receptors, LDL; Receptors, Retinoic Acid; Receptors, Thyroid Hormone; Sulfonamides; T 0901317; Triglycerides; very low density lipoprotein triglyceride
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[PDF]
[Abstract]
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12 |
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Metabolomics (liver and blood profiling) in a mouse model in response to fasting: A study of hepatic steatosis
article |
2007
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Author: |
Ginneken, V. van
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Verhey, E.
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Poelmann, R.
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Ramakers, R.
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Dijk, K.W. van
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Ham, L.
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Voshol, P.
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Havekes, L.
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Eck, M. van
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Greef, J. van der
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Keywords: |
Analytical research · Biomedical research · Hepatic steatosis · Lipids · Liver · Metabolomics · Starvation · Triacylglycerols · cholesterol · cholesterol ester · low density lipoprotein cholesterol · phosphatidylcholine · phospholipid derivative · triacylglycerol · animal experiment · animal model · animal tissue · article · blood examination · controlled study · diet restriction · fatty liver · high performance thin layer chromatography · lipid blood level · lipid storage · liver homogenate · male · mass spectrometry · metabolomics · mouse · nonhuman · priority journal · reversed phase liquid chromatography · starvation · Animals · Blood · Cholesterol Esters · Chromatography, High Pressure Liquid · Disease Models, Animal · Fatty Liver · Food Deprivation · Lipoproteins, LDL · Liver · Male · Mice · Mice, Inbred C57BL · Phosphatidylcholines · Phospholipids · Triglycerides · Mammalia
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A metabolomic approach was applied to a mouse model of starvation-induced hepatic steatosis. After 24 h of fasting it appears that starvation reduced the phospholipids (PL), free cholesterol (FC), and cholesterol esters (CE) content of low-density lipoproteins (LDL). In liver lipid profiles major changes were observed using different techniques. High performance thin layer chromatography (HPTLC)-measurements of liver-homogenates indicated a significant rise of FC with 192%, triacylglycerols (TG) with 456% and cholesterol esters (CE) with 268% after 24 h of starvation in comparison with the control group. Reversed phase liquid chromatography coupled to mass spectrometry measurements (LC-MS) of liver homogenate indicated that the intensity of Phosphatidylcholine (PC) in the 24-h starvation group dropped to 90% of the value in the control group while the intensity of CE and TG increased to 157% and 331%, respectively, of the control group. Interestingly, a 49:4-TG with an odd number of C atoms appeared during starvation. This unique triacylglycerol has all characteristics of a biomarker for detection of hepatic steatosis. These observations indicate that in mammals liver lipid profiles are a dynamic system which are readily modulated by environmental factors like starvation. © 2007 Elsevier B.V. All rights reserved.
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[Abstract]
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13 |
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Branching mutants of Aspergillus oryzae with improved amylase and protease production on solid substrates
article |
2005
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Author: |
Biesebeke, R. te
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Record, E.
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Biezen, N. van
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Heerikhuisen, M.
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Franken, A.
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Punt, P.J.
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Hondel, C.A.M.J.J. van den
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Keywords: |
Biology · Biotechnology · Enzyme kinetics · Enzymes · Fermentation · Growth kinetics · Hydrolysis · Microorganisms · Substrates · Yeast · Amylase · Branching mutants · Hydrolytic enzymes · Solid substrates · Mutagenesis · amylase · carrier protein · glucan 1,4 alpha glucosidase · phosphatidylglycerol · phosphatidylinositol · proteinase · fungus · gene expression · protein · allele · article · Aspergillus oryzae · enzyme activity · enzyme synthesis · fermentation · fungal biomass · fungal genetics · fungal strain · fungus growth · fungus hyphae · fungus mutant · genetic code · hydrolysis · microscopy · nonhuman · protein secretion · seed kernel · solid · sporogenesis · wheat · wild type · Amylases · Aspergillus oryzae · Biomass · Fungal Proteins · Gene Deletion · Glucan 1,4-alpha-Glucosidase · Hyphae · Morphogenesis · Mutagenesis, Insertional · Mutation · Peptide Hydrolases · Phospholipid Transfer Proteins · Spores, Fungal · Triticum · Aspergillus oryzae · Fungi · Triticum aestivum
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To study the relation between the number of hyphal tips and protein secretion during growth on a solid substrate, we have constructed two mutant strains of Aspergillus oryzae with increased hyphal branching. We have analysed hydrolytic enzyme activities during growth on wheat kernels (WK) of A. oryzae strains carrying the disrupted allele of the pclA gene encoding a secretion pathway specific (KEX2-like) endo-protease and the disrupted allele of the pg/pi-tp gene encoding a phosphatidylglycerol/phosphatidylinositol transfer protein. The biomass levels produced by the pclA and pg/pi-tp disrupted strains on wheat-based solid media were similar as found for the wild-type strain. However, the pclA disrupted strain showed much more compact colony morphology than the other two strains. Sporulation of the pclA and pg/pi-tp disrupted strains occurred, respectively, 2 days and 1 day later, compared to the wild type during fermentation on ground WK. During surface growth, microscopic analysis revealed that the hyphal growth unit length (L hgu) of the pclA and pg/pi-tp disrupted strains was, on average, 50 and 74% of that of the wild-type strain. This implies that in both mutant strains, a higher branching frequency occurs than in the wild-type strain. Compared to the wild-type strain, the pclA and pg/pi-tp disrupted strains produced at least 50% more amylase, at least 100% more glucoamylase and at least 90% more protease activity levels after growth on WK. These results support the hypothesis that branching mutants with an increased branching frequency can improve the solid state fermentation process. © Springer-Verlag 2005.
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[Abstract]
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14 |
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A thirteen week dietary toxicity study with 7-hydroxymatairesinol potassium acetate (HMRlignan) in rats
Plant lignan 7-hydroxymatairesinol (7-HMR) is a novel precursor of the mammalian lignan enterolactone. A 13 week toxicity study at dietary levels of 0, 0.25, 1, and 4% (w/w) of potassium acetate complex of 7-HMR (HMRlignan) was conducted in the Wistar rat. These dietary levels resulted in an average daily intake of 160, 640, and 2600 mg HMRlignan/kg body weight/day, respectively. A considerable systemic exposure of HMRlignan was verified by dose-related increases in plasma total (conjugated and unconjugated) concentration of 7-HMR and metabolites enterolactone, 7-hydroxyenterolactone, and matairesinol. Enterolactone appeared to be the major metabolite. Most (>96%) of the circulating 7-HMR and enterolactone was in conjugated form as measured from the low-dose rat plasma samples. HMRlignan exposure did not significantly affect clinical signs, ophthalmoscopy or neurobehavioural observations, and motor activity. Transient reductions in food intake and body weight gain in the mid-and high-dose group were ascribed to decreased palatability of the test feed. Only in males of the high-dose group the body weights remained slightly reduced throughout the study. In the high-dose group the number of thrombocytes (females), and total white blood cell count (males) were increased. Plasma triglycerides were dose-dependently depressed in males of all test groups and in females of the mid- and high-dose group, while plasma total cholesterol, and phospholipids were decreased in high-dose males. These changes, which have also been reported for other (flaxseed) lignans, were not considered to represent adverse effects. The relative weight of the kidneys was increased in males of the high-dose group. The weight of the full and empty caecum showed dose-related increases in males of all treatment groups and in females of the high-dose group. Absolute ovary weights were decreased in all treatment groups while decreases in relative ovary weights were confined to the mid- and high-dose group. In addition, a marginal lengthening of the estrus cycle was noted in high-dose females. Apart from prevention of hyaline droplet nephropathy in all high-dose male rats, there were no treatment-related histopathological alterations. It was concluded that HMRlignan showed weak antiestrogen-like activity which may be mediated through enterolactone metabolite. Based on declined ovary weight, the no observed adverse effect level of HMRlignan was set at 0.25% in feed corresponding to 160 mg/kg body weight/day. © 2004 Elsevier Inc. All rights reserved.
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[Abstract]
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15 |
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Evaluation of a subchronic (13-week) oral toxicity study, preceded by an in utero exposure phase, with arachidonic acid oil derived from Mortierella alpina in rats
Arachidonic acid oil (ARA-oil) derived from the fungus Mortierella alpina for use in infant nutrition was tested in a subchronic (13-week) oral toxicity study in rats, preceded by an in utero exposure phase. The ARA-oil was administered as admixture to the rodent diet at dose levels of 3000 ppm, 15,000 ppm and 75,000 ppm. An additional high-dose group received 75,000 ppm ARA-oil in combination with 55,000 ppm fish oil containing docosahexaenoic acid (DHA), at a ratio of ARA to DHA, comparable to the ratio in mother's milk of 2:1. The total levels of fat in each diet were kept constant by adding the appropriate amounts of corn oil. A concurrent control group received 130,000 ppm corn oil in the diet. An additional carrier control group was fed unsupplemented rodent diet. Administration of the test substances from 4 weeks prior to mating, throughout mating, gestation, lactation of parental (F0) animals and weaning of the F1 pups did not affect fertility or reproductive performance, nor the general condition of pups, viability, sex ratio or number of pups. Pup weight gain in the ARA/DHA- oil group was lower than the controls administered equal amounts of corn oil. In the subsequent subchronic study survival, clinical signs, body weight gain and food consumption were not adversely affected by the test substances. Ophthalmoscopic examination did not reveal any treatment-related changes. There were no treatment-related effects observed up to dietary test substance concentrations of 15,000 ppm. The following statistically significant differences were found in the ARA high-dose group and /or in the ARA/DHA group compared to the corn oil control group: decreased alkaline phosphatase activity, decreases in cholesterol, triglycerides and phospholipids concentrations, increased creatinine and urea concentrations. Furthermore, these groups showed increased adrenal, spleen and liver weights. The incidence of hepatocellular vacuolation was increased in females of the ARA high-dose group and the ARA/DHA group. Oil droplets were observed in the mesenteric lymph nodes and in the intestinal villi in the ARA high-dose group and the ARA/DHA group. In addition, lipogranulomas were observed in the mesenteric lymph nodes in these groups. The observed changes in the high-dose groups may be effects of the high intake of high-fat levels, rather than specific effects of the ARA-oil. The no-observed-effect level in this study was placed at 15,000 ppm ARA-oil. This level is equivalent to approximately 970 mg ARA-oil/kg body weight/day. (C) 2000 Elsevier Science Ltd.
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[Abstract]
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16 |
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Profiles of metabolites and gene expression in rats with chemically induced hepatic necrosis
article |
2005
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Author: |
Heijne, W.H.M.
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Lamers, R.J.A.N.
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Bladeren, P.J. van
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Groten, J.P.
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Nesselrooij, J.H.J. van
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Ommen, B. van
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Keywords: |
Biology · Physiological Sciences · Bromobenzene · Centrilobular necrosis · Hepatotoxicity · Metabolite profiling · Metabolomics · Toxicogenomics · Transcriptomics · alanine · asialoglycoprotein receptor · beta actin · bromobenzene · casein kinase II · creatine · creatinine · cyclin G1 · cycline · dimethylglycine · ferritin · fibrinogen · fructose bisphosphate aldolase · glyceraldehyde 3 phosphate dehydrogenase · lactic acid · methionine · nucleophosmin · orosomucoid · peroxiredoxin · phosphatidylcholine sterol acyltransferase · phosphoglycerate mutase · phospholipid · protein bcl 2 · protein p21 · protein p53 · taurine · tissue inhibitor of metalloproteinase 1 · tubulin · tyrosine · unindexed drug · amino acid metabolism · animal model · apoptosis · article · blood level · controlled study · DNA microarray · dose response · gene · gene expression · gene sequence · glycolysis · liver necrosis · liver toxicity · male · metabolomics · nonhuman · nuclear magnetic resonance spectroscopy · nucleotide sequence · priority journal · rat · transcriptomics · urine level · Amino Acids · Animals · Bromobenzenes · Dose-Response Relationship, Drug · Gene Expression Profiling · Hepatitis, Toxic · Liver · Male · Necrosis · Principal Component Analysis · Rats · Rats, Wistar · Transcription, Genetic
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This study investigated whether integrated analysis of transcriptomics and metabolomics data increased the sensitivity of detection and provided new insight in the mechanisms of hepatotoxicity. Metabolite levels in plasma or urine were analyzed in relation to changes in hepatic gene expression in rats that received bromobenzene to induce acute hepatic centrilobular necrosis. Bromobenzene-induced lesions were only observed after treatment with the highest of 3 dose levels. Multivariate statistical analysis showed that metabolite profiles of blood plasma were largely different from controls when the rats were treated with bromobenzene, also at doses that did not elicit histopathological changes. Changes in levels of genes and metabolites were related to the degree of necrosis, providing putative novel markers of hepatotoxicity. Levels of endogenous metabolites like alanine, lactate, tyrosine and dimethylglycine differed in plasma from treated and control rats. The metabolite profiles of urine were found to be reflective of the exposure levels. This integrated analysis of hepatic transcriptomics and plasma metabolomics was able to more sensitively detect changes related to hepatotoxicity and discover novel markers. The relation between gene expression and metabolite levels was explored and additional insight in the role of various biological pathways in bromobenzene-induced hepatic necrosis was obtained, including the involvement of apoptosis and changes in glycolysis and amino acid metabolism. The complete Table 2 is available as a supplemental file online at http://taylorandfrancis.metapress.com/openurlasp?genre=journal&issn=0192-6233. To access the file, click on the issue link for 33(4), then select this article. A download option appears at the bottom of this abstract. In order to access the full article online, you must either have an individual subscription or a member subscription accessed through www.toxpath.org. Copyright © by the Society of Toxicologic Pathology.
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[Abstract]
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17 |
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Subchronic (13-week) oral toxicity study, preceded by an in utero exposure phase, with arachidonate-enriched triglyceride oil (SUNTGA40S) in rats
article |
2006
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Author: |
Lina, B.A.R.
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Wolterbeek, A.P.M.
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Suwa, Y.
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Fujikawa, S.
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Ishikura, Y.
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Tsuda, S.
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Dohnalek, M.
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Keywords: |
Biology · Toxicology and Applied Pharmacology · Arachidonic acid · Docosahexaenoic acid · Rat · Reproductive indices · Safety · Sub-chronic toxicity · SUNTGA40S · alkaline phosphatase · arachidonic acid · cholesterol · corn oil · docosahexaenoic acid · fat · fish oil · hemoglobin · phospholipid · triacylglycerol · animal experiment · animal model · animal tissue · article · cognition · controlled study · diet supplementation · dietary intake · enzyme activity · erythrocyte count · fat intake · female · fertility · food intake · growth · health status · hematocrit · lactation · lipid diet · low fat diet · male · mating · mouth disease · nonhuman · ophthalmoscopy · pregnancy · prenatal exposure · progeny · prothrombin time · reticulocyte · risk assessment · sex ratio · sexual behavior · spleen weight · urinalysis · weight gain · Administration, Oral · Animals · Animals, Newborn · Animals, Suckling · Arachidonic Acid · Body Weight · Dietary Fats, Unsaturated · Docosahexaenoic Acids · Dose-Response Relationship, Drug · Female · Humans · Infant Food · Infant Nutrition Physiology · Infant, Newborn · Lactation · Lipids · Male · Organ Size · Pregnancy · Prenatal Exposure Delayed Effects · Random Allocation · Rats · Rats, Wistar · Reproduction · Sex Factors · Toxicity Tests, Chronic · Triglycerides · Animalia · Rattus norvegicus · Scombridae gen. sp. · Zea mays
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Polyunsaturated fatty acids (PUFAs), such as arachidonic acid (ARA) and docosahexaenoic acid (DHA) are natural constituents found in human milk, fish oil or egg yolk. Until recently, infant formulas, though providing the essential fatty acid precursors for these PUFAs, did not contain preformed ARA or DHA. In this study the safety of SUNTGA40S as source of ARA, not only for use in infant formulas but also for nutritional products or food supplements, was evaluated in a subchronic study in Wistar rats, preceded by a 4-week pretreatment period of parental (F0) rats and exposure of the F0 dams throughout mating, gestation and lactation. SUNTGA40S was administered at dietary levels of 0.5%, 1.5% and 5% (wt/wt) adjusted with corn oil to 5.76% added fat. An additional group received 3.65% (wt/wt) SUNTGA40S in conjunction with 2.11% (wt/wt) high DHA Tuna oil, providing an ARA:DHA ratio of 2.7:1. High-fat and low-fat controls received basal diet with or without 5.76% corn-oil supplement. The content, stability and homogeneous distribution of the test substances in the diet were confirmed under study conditions. The administration of SUNTGA40S, with or without DHA oil, did not affect health, growth, fertility or reproductive performance of the parental rats, nor pup characteristics (condition, weight gain, viability, number per litter or sex ratio). In the subchronic study with the offspring (F1) rats, no significant differences were found in condition, neurobehavioural observations, ophthalmoscopy, growth, urinalysis or macroscopic and microscopic findings between the test groups and the low-fat or the high-fat controls. In males of the 5% SUNTGA40S and the SUNTGA40S/DHA group, red blood cell counts, haemoglobin concentration and packed cell volume were lower and reticulocytes were slightly higher than in the high-fat and low-fat control groups. Cholesterol, triglycerides and phospholipids in plasma were lower than in the high-fat controls in both sexes in the 5% SUNTGA40S and the SUNTGA40S/DHA group and (for triglycerides only) in the 1.5% SUNTGA group. Due to the administration of extra dietary fat, food intake and prothrombin time (males only) were lower and alkaline phosphatase activity was higher in all the high-fat groups, including the corn-oil controls, as compared to the low-fat controls. The weight of the spleen was higher in males of the 5% SUNTGA40S and the SUNTGA40S/DHA group compared to both the low-fat and the high-fat controls. The effects noted in this study at high dose levels of SUNTGA40S are consistent with previously reported physiological responses to dietary intake of high PUFA containing oils. The present results provide evidence that SUNTGA40S is a safe source of arachidonic acid. Except during lactation when the intake in dams doubled, 5% Suntga40S in the diet was equivalent to an overall intake of approximately 3 g/kg body weight/day in F0 and F1 animals. © 2005 Elsevier Ltd. All rights reserved.
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[Abstract]
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18 |
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Weight loss predictability by plasma metabolic signatures in adults with obesity and morbid obesity of the DiOGenes study
article |
2016
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Author: |
Stroeve, J.H.M.
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Saccenti, E.
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Bouwman, J.
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Dane, A.
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Strassburg, K.
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Vervoort, J.
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Hankemeier, T.
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Astrup, A.
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Smilde, A.K.
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Ommen, B. van
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Saris, W.H.M.
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Keywords: |
Nutrition · 3 hydroxy 2 methylpropionic acid · 3 hydroxybutyric acid · Acetic acid · Acetoacetic acid · Alanine · Cholesterol · Creatine · Creatinine · Fatty acid · Glucose · Glycine · High density lipoprotein cholesterol · Insulin · Isoleucine · Isovaleric acid · Lactic acid · Low density lipoprotein cholesterol · Phosphatidylcholine · Proline · Triacylglycerol · Tyrosine · Valine · Adult · Amino acid blood level · Analytical parameters · Cholesterol blood level · Controlled study · Creatinine blood level · Diastolic blood pressure · Energy metabolism · Fatty acid blood level · Female · Glucose blood level · Human · Insulin blood level · Liquid chromatography · Low calory diet · Male · Mass spectrometry · Morbid obesity · Nuclear magnetic resonance · Obesity · Phospholipid blood level · Protein blood level · Randomized controlled trial · Systolic blood pressure · Triacylglycerol blood level · Waist circumference · Weight reduction · Food and Nutrition · Healthy Living · Life · MSB - Microbiology and Systems Biology · ELSS - Earth, Life and Social Sciences
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Objective: Aim is to predict successful weight loss by metabolic signatures at baseline and to identify which differences in metabolic status may underlie variations in weight loss success. Methods: In DiOGenes, a randomized, controlled trial, weight loss was induced using a low calorie diet (800 kcal) for 8-weeks. Men (N5236) and women (N5431) as well as groups with overweight/obesity and morbid obesity were studied separately. The relation between the metabolic status before weight loss and weight loss was assessed by stepwise regression on multiple datasets, including anthropometric parameters, NMR-based plasma metabolites, and LC-MS-based plasma lipid species. Results: Maximally, 57% of the variation in weight loss success can be predicted by baseline parameters. The most powerful predictive models were obtained in subjects with morbid obesity. In these models, the metabolites most predictive for weight loss were acetoacetate, triacylglycerols, phosphatidylcholines, specific amino acids, and creatine and creatinine. This metabolic profile suggests that high energy metabolism activity results in higher amounts of weight loss. Conclusions: Possible predictive (pre-diet) markers were found for amount of weight loss for specific subgroups.
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[Abstract]
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19 |
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Combined TLR2 and TLR4 ligation in the context of bacterial or helminth extracts in human monocyte derived dendritic cells: Molecular correlates for Th1/Th2 polarization
article |
2009
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Author: |
Riet, E. van
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Everts, B.
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Retra, K.
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Phylipsen, M.
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Hellemond, J.J. van
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Tielens, A.G.M.
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Kleij, D. van der
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Hartgers, F.C.
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Yazdanbakhsh, M.
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Keywords: |
Biology · messenger RNA · mitogen activated protein kinase p38 · Notch4 receptor · phospholipid · protein c fos · toll like receptor 2 · toll like receptor 4 · bacterial antigen · mitogen activated protein kinase · parasite antigen · TLR2 protein, human · TLR4 protein, human · article · Ascaris lumbricoides · controlled study · dendritic cell · enzyme activation · Escherichia coli · gene activity · gene expression profiling · gene expression regulation · human · human cell · Listeria monocytogenes · lymphocyte function · nonhuman · polarization · Schistosoma mansoni · signal transduction · T lymphocyte activation · Th1 cell · Th2 cell · animal · cytology · gene expression · immunology · metabolism · microbiology · monocyte · reverse transcription polymerase chain reaction · Animals · Antigens, Bacterial · Antigens, Helminth · Ascaris lumbricoides · Dendritic Cells · Enzyme Activation · Escherichia coli · Gene Expression · Gene Expression Profiling · Humans · Listeria monocytogenes · Mitogen-Activated Protein Kinases · Monocytes · Reverse Transcriptase Polymerase Chain Reaction · RNA, Messenger · Schistosoma mansoni · Signal Transduction · Th1 Cells · Th2 Cells · Toll-Like Receptor 2 · Toll-Like Receptor 4
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Background: Recognition of pathogens by dendritic cells (DCs) through interaction with pattern recognition receptors, including Toll like receptors (TLR), is crucial for the initiation of appropriate polarized T helper (Th) cell responses. Yet, the characteristics and differences in molecular profiles of DCs with different T cell polarizing capacities are still poorly defined. To address this issue, the molecular profile of human monocyte derived DCs was characterized after exposure to TLR4 ligand LPS in combination with the Th1 promoting bacterial extracts from Listeria monocytogenes and Escherichia coli or the Th2 promoting helminth derived phospholipids from Schistosoma mansoni and Ascaris lumbricoides, all with TLR2 activating capacity. Results: With regard to the signalling pathways activated upon exposure to LPS and the TLR2 activating compounds, we find that the ratio of activated Mitogen Activated Protein Kinases (MAPK) p-ERK/p-p38 is lower in DCs stimulated with the bacterial products compared to DCs stimulated with the helminth products, which correlates with the Th1 and Th2 polarizing capacity of these compounds. Furthermore, analysis of the mRNA expression levels of a set of 25 carefully selected genes potentially involved in modulation of T cell polarization revealed that the mRNA expression of notch ligand delta-4 and transcription factor c-fos are differentially regulated and show a strong correlation with Th1 and Th2 polarization, respectively. Conclusion: This study shows that combined TLR2 and TLR4 activation in the context of different antigen sources can induce very distinct molecular profiles in DCs and suggests that the Th1/Th2 polarizing capacity of compounds can be predicted with the molecular signature they induce in DCs. © 2009 van Riet et al; licensee BioMed Central Ltd.
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[Abstract]
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20 |
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Atorvastatin increases HDL cholesterol by reducing CETP expression in cholesterol-fed APOE*3-Leiden.CETP mice
article |
2008
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Author: |
Haan, W. de
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Hoogt, C.C. van der
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Westerterp, M.
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Hoekstra, M.
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Dallinga-Thie, G.M.
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Princen, H.M.G.
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Romijn, J.A.
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Jukema, J.W.
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Havekes, L.M.
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Rensen, P.C.N.
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Keywords: |
Health · CETP · High-density lipoprotein · HMGCoA reductase · Statin · Transgenic mice · ABC transporter A1 · apolipoprotein A1 · apolipoprotein E3 · atorvastatin · cholesterol ester transfer protein · high density lipoprotein · high density lipoprotein cholesterol · messenger RNA · phospholipid transfer protein · scavenger receptor BI · very low density lipoprotein · very low density lipoprotein cholesterol · animal experiment · animal model · article · cholesterol blood level · cholesterol diet · controlled study · drug effect · gene expression · hypercholesterolemia · lipoprotein blood level · lipoprotein metabolism · male · mouse · nonhuman · priority journal · protein expression · transgenic mouse · Animals · Apolipoprotein E3 · Cholesterol Ester Transfer Proteins · Cholesterol, Dietary · Cholesterol, HDL · Cholesterol, VLDL · Dose-Response Relationship, Drug · Female · Gene Expression · Heptanoic Acids · Humans · Hydroxymethylglutaryl-CoA Reductase Inhibitors · Hypercholesterolemia · Liver · Male · Mice · Mice, Inbred C57BL · Mice, Transgenic · Pyrroles · RNA, Messenger
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Objective: In addition to lowering low-density lipoprotein (LDL)-cholesterol, statins modestly increase high-density lipoprotein (HDL)-cholesterol in humans and decrease cholesteryl ester transfer protein (CETP) mass and activity. Our aim was to determine whether the increase in HDL depends on CETP expression. Methods and results: APOE*3-Leiden (E3L) mice, with a human-like lipoprotein profile and a human-like responsiveness to statin treatment, were crossbred with mice expressing human CETP under control of its natural flanking regions resulting in E3L.CETP mice. E3L and E3L.CETP mice were fed a Western-type diet with or without atorvastatin. Atorvastatin (0.01% in the diet) reduced plasma cholesterol in both E3L and E3L.CETP mice (-26 and -33%, P < 0.05), mainly in VLDL, but increased HDL-cholesterol only in E3L.CETP mice (+52%). Hepatic mRNA expression levels of genes involved in HDL metabolism, such as phospholipid transfer protein (Pltp), ATP-binding cassette transporter A1 (Abca1), scavenger receptor class B type I (Sr-b1), and apolipoprotein AI (Apoa1), were not differently affected by atorvastatin in E3L.CETP mice as compared to E3L mice. However, in E3L.CETP mice, atorvastatin down-regulated the hepatic CETP mRNA expression (-57%; P < 0.01) as well as the total CETP level (-29%) and cholesteryl esters (CE) transfer activity (-36%; P < 0.05) in plasma. Conclusions: Atorvastatin increases HDL-cholesterol in E3L.CETP mice by reducing the CETP-dependent transfer of cholesterol from HDL to (V)LDL, as related to lower hepatic CETP expression and a reduced plasma (V)LDL pool. © 2007 Elsevier Ireland Ltd. All rights reserved.
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[Abstract]
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