Abstract：
:The effect of inhibiting lysosomal protein degradation on the activity of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase was determined using a mouse mammary cell line (TS-85) which expresses a temperature-sensitive mutation in the ubiquitin degradative pathway. Incubating cells for 18 hr in medium containing 20 mM NH4Cl did not alter total protein synthesis or cell growth, but it did inhibit the rate of total protein degradation by 19%, which is consistent with the known inhibitory effect of NH4Cl on lysosomal protein degradation. NH4Cl treatment also resulted in an increase (81% +/- 20) in HMG-CoA reductase activity. The increase in reductase activity was not correlated with changes in the phosphorylation state of the enzyme or with alteration in the relative rate of reductase synthesis. However, the basal degradation rate of the reductase was significantly inhibited, and after NH4Cl treatment, the half-life of the enzyme increased from 4.0 +/- 0.4 hr to 8.3 +/- 0.8 hr. The change in the rate of reductase degradation can account completely for the increase in reductase activity observed in NH4Cl-treated cells. The accelerated degradation of HMG-CoA reductase induced by 25-hydroxycholesterol treatment was not affected by either NH4Cl or by inactivation of the ubiquitin degradative pathway. Therefore, two different mechanisms may be responsible for the accelerated degradation and basal degradation of HMG-CoA reductase. The latter can be inhibited by NH4Cl and may imply that under basal conditions the enzyme may be degraded in lysosomes.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Tanaka RD,Li AC,Fogelman AM,Edwards PAsubject
Has Abstractpub_date
1986-03-01 00:00:00pages
261-73issue
3eissn
0022-2275issn
1539-7262journal_volume
27pub_type
杂志文章abstract：:This study examined the in vivo relationship between expression of the HDL receptor scavenger receptor class B (SR-BI) and corresponding structural changes in the rat adrenocortical cell microvillar compartment. Using hormonal stimulation and withdrawal protocols, we were able to manipulate adrenal SR-BI levels and ca...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2002-06-01 00:00:00
abstract：:Fatty acid compositions of glycerophosphatides of developing chick embryonic brain and liver were compared. In brain, ethanolamine and serine glycerophosphatides contained 30-40% polyunsaturated fatty acids, lecithin almost none (except for arachidonic). In the liver, these acids were equally distributed in the phosph...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1966-09-01 00:00:00
abstract：:This study describes a variant of familial apoA-I deficiency associated with a moderate risk for premature coronary artery disease. The proband, a 25-year-old man of Philippine origin, and his 62-year-old maternal aunt had peripheral corneal opacification, xanthelasma, and planar xanthoma; the aunt had coronary artery...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1991-10-01 00:00:00
abstract：:Apolipoprotein E (apoE) polymorphism is a genetic determinant of plasma lipid levels and of coronary heart disease (CHD) risk. We determined the apoE phenotypes and plasma lipid levels in 1577 youths aged 3 to 18 years in 1980. The subjects were randomly selected from five areas of Finland. ApoE phenotyping was perfor...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:The transport of LDL-derived cholesterol from lysosomes to peroxisomes is facilitated by membrane contacts formed between the lysosomal protein synaptotagmin VII and the peroxisomal lipid phosphatidylinositol 4, 5-bisphosphate [PI(4,5)P2]. Here, we used RNA interference to search for regulators of PI(4,5)P2 and to stu...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M082149
更新日期：2018-03-01 00:00:00
abstract：:Synthesis of apolipoprotein (apo)E in hepatocytes leads to both secretion and retention in cell surface pools. Inclusion of Brefeldin A to HepG2 cells prompted a rapid decrease of cell surface apoE to about 37% of control values after a 3-h incubation. The t(1/2) for this dynamic pool was estimated to be 15 min. In co...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2001-09-01 00:00:00
abstract：:Recently we evaluated an isotope ratio method (IRM) for measurement of cholesterol absorption in 14 patients (15 experiments) hospitalized in the metabolic ward by comparing it to simultaneous measurements with a fecal radioactivity method (FRM) and found good to excellent agreement between two procedures (Samuel, P.,...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1982-03-01 00:00:00
abstract：:Lipoproteins internalized by the LDL receptor (LDLR) are released from this receptor in endosomes through a process that involves acid-dependent conformational changes in the receptor ectodomain. How acidic pH promotes this release process is not well understood. Here, we assessed roles for six histidine residues for ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M070938
更新日期：2017-02-01 00:00:00
abstract：:A strategy has been developed for archaebacterial lipid analysis which provides three times the information to describe archaebacterial isolates and is compatible with simultaneous eubacterial/eukaryotic lipid analysis of environmental samples. Eubacterial and micro-eukaryotic biomass, community structure, and nutriti...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1991-04-01 00:00:00
abstract：:Rat lymph chylomicrons were treated with rat heparin-releasable hepatic lipase (HL) or with bovine milk lipoprotein lipase (LPL). The ability of the resulting particles to be taken up by the liver in vivo was assessed following their infusion into the portal vein of partially hepatectomized animals. The following obse...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1988-08-01 00:00:00
abstract：:Long-chain fatty acids are the most important substrates for the heart. In addition, they have been shown to affect signalling pathways and gene expression. To explore the effects of long-chain fatty acids on cardiac gene expression, neonatal rat ventricular myocytes were cultured for 48 h with either glucose (10 mm),...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2000-01-01 00:00:00
abstract：:We have developed the technique of rapid (< 2 h) centrifugal ultrafiltration to measure the inter-mixed micellar/vesicular (non-lecithin-associated) bile salt (BS) concentrations (IMC) of individual BS in model biles. This methodology uses a centrifugal concentrator with a reinforced membrane, through which a small fr...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1993-07-01 00:00:00
abstract：:Solid-phase extraction (SPE) methods are easy, rapid, and reliable. Their growing popularity is in part due to their operational simplicity and cost reduction in solvents, and partly because they are easier to automate. Sphingolipids are implicated in various cellular events such as growth, differentiation, and apopto...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2000-09-01 00:00:00
abstract：:In vivo single-voxel magnetic resonance spectroscopy (MRS) at 4.7T and ex vivo high-resolution proton magnetic resonance spectroscopy (HR-NMR) at 500 MHz were used to study the composition of adipose tissues in Zucker obese and Zucker lean rats. Lipid composition was characterized by unsaturation and polyunsaturation ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M011825
更新日期：2011-02-01 00:00:00
abstract：:Acylglycerophosphate acyltransferase 4 (AGPAT4)/lysophosphatidic acid acyltransferase delta catalyzes the formation of phosphatidic acid (PA), a precursor of triacyl-glycerol (TAG). We investigated the effect of Agpat4 gene ablation on white adipose tissue (WAT) after finding consistent expression across depots. Epidi...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M079152
更新日期：2017-10-01 00:00:00
abstract：:The rate of lipolytic enzyme-catalyzed reactions yielding water-soluble products can be measured by isobaric titration. The method is based upon the measurement of the amount of substrate that must be added to a monalayer to maintain constant surface pressure during the course of the enzymatic reaction. The rate const...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1975-01-01 00:00:00
abstract：:Hepatic free cholesterol levels are influenced by cholesterol synthesis and ester formation, which, in turn, might regulate cholesterol secretion into bile and plasma. We manipulated the rates of hepatic cholesterol synthesis and esterification and measured biliary and very low density lipoprotein (VLDL) cholesterol s...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：:The accumulation of phosphatidylcholine hydroperoxide (PCOOH), a primary oxidation product of phosphatidylcholine (PC), in blood plasma and tissues has been observed in various pathological conditions, including atherosclerosis. However, the biological roles of PCOOH in these conditions remain unknown. To estimate the...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M800582-JLR200
更新日期：2009-05-01 00:00:00
abstract：:Significant amounts of ursodeoxycholic acid (UDCA) used for the treatment of patients with primary biliary cirrhosis (PBC) become epimerized at C-3 to isoUDCA. We investigated the metabolism of isoUDCA and a possible pharmacologic effect in five patients (51.4 +/- 5.8 years old; 3 females, 2 males) with PBC and persis...
journal_title：Journal of lipid research
pub_type： 临床试验,杂志文章
doi：
更新日期：2001-05-01 00:00:00
abstract：:Adipocyte differentiation and function have become areas of intense focus in the field of energy metabolism; however, understanding the role of specific genes in the establishment and maintenance of fat cell function can be challenging and complex. In this review, we offer practical guidelines for the study of adipocy...
journal_title：Journal of lipid research
pub_type： 杂志文章,评审
doi：10.1194/jlr.R046441
更新日期：2014-04-01 00:00:00
abstract：:Apolipoprotein (apo)A-I is the major protein component of HDL and the cofactor for LCAT. We describe a large Spanish kindred, living in the Mediterranean Island of Mallorca, that presents a dominant form of hypoalphalipoproteinemia. The lipid profile of this family was studied because the proband, a 40-year-old male p...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2002-01-01 00:00:00
abstract：:Glycerolipid and apoB synthesis and secretion were examined in hepatocytes obtained from fetal, suckling (day 6), and adult rats in order to examine the developmental regulation of lipoprotein production. The capacity to synthesize [3H]triacylglycerol (from [3H]glycerol) followed the order: adult greater than day 6 gr...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
abstract：:It has been demonstrated that the alkenylacyl class of ethanolamine phospholipid (PE) represents one of the major forms of eicosapentaenoic acid (EPA)-containing phospholipid in the circulating platelets isolated from human subjects consuming a fish oil concentrate. Since the alkenylacyl PE from human platelets is enr...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：:The behavior of human omental fat cells in vitro has been examined in order to define conditions under which glucose is converted to glyceride-glycerol and glyceride fatty acids. Synthesis of glyceride fatty acids from glucose reached maximal rates only after several hours of incubation in Krebs-Henseleit bicarbonate ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1969-05-01 00:00:00
abstract：:Macrophages and arterial chondroitin sulfate proteoglycans (CSPG) are probably associated with extracellular and intracellular lipoprotein deposition during atherogenesis. We found that human arterial CSPG can be used to select subclasses from low density lipoprotein (LDL) with different structural properties and capa...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1990-08-01 00:00:00
abstract：:The mechanisms involved in the development of alcoholic liver disease (ALD) are not well established. We investigated the involvement of acyl-CoA: diacylglycerol acyltransferase 2 (DGAT2) upregulation in mediating hepatic fat accumulation induced by chronic alcohol consumption. Chronic alcohol feeding caused fatty liv...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M007948
更新日期：2010-11-01 00:00:00
abstract：:Bile acids are physiological detergents that generate bile flow and facilitate intestinal absorption and transport of lipids, nutrients, and vitamins. Bile acids also are signaling molecules and inflammatory agents that rapidly activate nuclear receptors and cell signaling pathways that regulate lipid, glucose, and en...
journal_title：Journal of lipid research
pub_type： 杂志文章,评审
doi：10.1194/jlr.R900010-JLR200
更新日期：2009-10-01 00:00:00
abstract：:Previous in vitro studies have revealed that oxidized low density lipoprotein (OxLDL) has negative effects on the proliferation and activity of endothelial progenitor cells (EPCs). Here, we evaluated the effect of OxLDL on the therapeutic potential of EPCs in ischemia-induced neovascularization. EPCs derived from mobi...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M600251-JLR200
更新日期：2007-03-01 00:00:00
abstract：:Epidemiological studies in Greenland Eskimos led to the hypothesis that marine oils rich in n-3 fatty acids (also referred to as omega (omega)-3 fatty acids) are hypolipidemic and ultimately antiatherogenic. Metabolically controlled trials in which large amounts of fish oil were fed to normal volunteers and hyperlipid...
journal_title：Journal of lipid research
pub_type： 杂志文章,评审
doi：
更新日期：1989-06-01 00:00:00
abstract：:Vitamin A-transporting protein in chicken plasma was purified by column chromatography on DEAE-Sephadex and Sephadex G-100; the protein formed a complex of retinol-binding protein (RBP) with prealbumin (PA). The molecular weight of the 1:1 molar complex was estimated to be 76,000 by gel filtration, and the sedimentati...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1975-05-01 00:00:00
