Oxysterols
Mostrando 1-12 de 32 artigos, teses e dissertações.
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1. Efeito dos oxisteróis na sinalização através de cavéolas e sua relevância na aterosclerose / Effect of oxysterols in cell signaling through caveolae and its relevance to atherosclerosis
Oxisteróis (por exemplo, 7hidroxicolesterol) são gerados por modificações oxidativas que ocorrem na molécula de colesterol. Podem ser encontrados em elevados níveis plasmáticos em pacientes com aterosclerose e como componentes da placa aterosclerótica. Considerando que o colesterol é o principal componente da cavéola (domínios específicos da memb
Publicado em: 2011
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2. Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis
Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they
Brazilian Journal of Medical and Biological Research. Publicado em: 2008-07
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3. Efeito citotóxico causado por emulsão lipídica contendo 7-cetocolesterol (OxLE) em cultura de células tumorais / Cytotoxic effects caused by 7-ketocholesterol-containing emulsion (OXLE) in tumor cells in culture
Oxysterols are oxygenated derivatives of cholesterol that may be formed by autoxidation or by action of specific enzymes. They exhibit a number of biologic activities including inhibition of cellular proliferation and cytotoxicity. Among oxysterols, 7-ketocholesterol (7-KC), that differs form cholesterol by a functional ketone group at C7, is known to induce
Publicado em: 2004
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4. Determinação dos óxidos de colesterol em pacientes diabéticos e intolerantes à glicose / Cholesterol oxides as biomarkers of oxidative stress in type 1 and type 2 diabetes mellitus
Oxidative stress can play an important role in the etiology of the complications of diabetes mellitus. The increase in the production of oxidant species promotes alterations in endogenous molecules, including cholesterol. Cholesterol oxides (COx) are formed by the oxidation of cholesterol by enzymatic processes or by processes involving free radicals. They p
Publicado em: 2004
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5. Oxysterols present in atherosclerotic tissue decrease the expression of lipoprotein lipase messenger RNA in human monocyte-derived macrophages.
The presence of oxysterols in macrophages isolated from atherosclerotic tissue and the effect of oxysterols on the regulation of lipoprotein lipase (LPL) mRNA were studied. Both rabbit and human macrophages, freshly isolated from atherosclerotic aorta, show about the same distribution of oxysterols, analyzed by isotope dilution mass spectrometry, except that
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6. Activation of the orphan nuclear receptor steroidogenic factor 1 by oxysterols
Steroidogenic factor 1 (SF-1), an orphan member of the intracellular receptor superfamily, plays an essential role in the development and function of multiple endocrine organs. It is expressed in all steroidogenic tissues where it regulates the P450 steroidogenic genes to generate physiologically active steroids. Although many of the functions of SF-1 in viv
The National Academy of Sciences of the USA.
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7. The hypocholesterolemic agent LY295427 up-regulates INSIG-1, identifying the INSIG-1 protein as a mediator of cholesterol homeostasis through SREBP
Oxysterols regulate cholesterol homeostasis through liver X receptor (LXR; cholesterol-lowering)- and sterol regulatory element-binding protein (SREBP; cholesterol-raising)-mediated signaling pathways. Previously we reported that the hypocholesterolemic agent LY295427 (4α-allylcholestan-3α-ol) reverses oxysterol-mediated suppression of SREBP processing. We
The National Academy of Sciences.
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8. Do oxysterols control cholesterol homeostasis?
American Society for Clinical Investigation.
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9. Structural requirements of ligands for the oxysterol liver X receptors LXRα and LXRβ
LXRα and -β are nuclear receptors that regulate the metabolism of several important lipids, including cholesterol and bile acids. Previously, we have proposed that LXRs regulate these pathways through their interaction with specific, naturally occurring oxysterols, including 22(R)-hydroxycholesterol, 24(S)-hydroxycholesterol, and 24(S),25-epoxycholesterol.
The National Academy of Sciences.
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10. NAD(P)H Oxidase Nox-4 Mediates 7-Ketocholesterol-Induced Endoplasmic Reticulum Stress and Apoptosis in Human Aortic Smooth Muscle Cells
The mechanisms involved in the cytotoxic action of oxysterols in the pathogenesis of atherosclerosis still remain poorly understood. Among the major oxysterols present in oxidized low-density lipoprotein, we show here that 7-ketocholesterol (7-Kchol) induces oxidative stress and/or apoptotic events in human aortic smooth muscle cells (SMCs). This specific ef
American Society for Microbiology.
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11. Caveolin mRNA levels are up-regulated by free cholesterol and down-regulated by oxysterols in fibroblast monolayers
In confluent fibroblast monolayers, an increase in the selective uptake of free cholesterol (FC) from plasma low density lipoprotein (LDL) was accompanied by an increase in FC efflux. The rate of FC efflux was proportional to the FC content of the cell surface caveolae and to mRNA levels of caveolin, an FC-binding protein of caveolae. Inhibitors of LDL–FC
The National Academy of Sciences of the USA.
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12. Control of cellular cholesterol efflux by the nuclear oxysterol receptor LXRα
LXRα is a nuclear receptor that has previously been shown to regulate the metabolic conversion of cholesterol to bile acids. Here we define a role for this transcription factor in the control of cellular cholesterol efflux. We demonstrate that retroviral expression of LXRα in NIH 3T3 fibroblasts or RAW264.7 macrophages and/or treatment of these cells
The National Academy of Sciences.