Abstract：
:The technique of freeze fracture was used to visualize triglyceride (TG) hydrolysis and the production of lipolytic products (LPs) in vitro and in vivo in the presence of bile salts (BS). Three systems were investigated: pure lipolytic products (oleic acid and monoolein) in the presence of a pure bile salt (taurodeoxycholate (TDC)), lipolytic products produced from TG by pancreatic lipase in the presence of a variety of bile salts, and lipolytic products produced in the intestine of the killifish, Fundulus heteroclitus, after fat feeding. In vitro, lamellae (4-5 nm thick with 0-8-nm water spacings) appeared on the surface of TG droplets in all preparations with LP/BS molar ratios of 1.5 or greater and spherical vesicles (diameter range, 20-130 nm) were produced from these lamellae. With model killifish bile (taurocholate-cholate 1:1) at LP/BS ratios between 1.5 and 4, homogeneous vesicles or particles (mean diameter, 23.8 nm) were produced by lipase at pH 6.9. In vivo, lamellar product phases also occurred after fat feeding. The smallest visible LP/BS structures by freeze fracture electron microscopy were approximately 20 nm globular particles. Large disc-shaped micelles either were not present or were below the resolution limit of the replica (approximately 10 nm). The dominant aggregated lipolytic product phase was composed of multiple layers of rough-textured lamellae. No evidence of cubic structure was seen. These results show that lamellar and vesicular lipolytic product phases can be intermediates in intestinal fat digestion. However, no evidence for the direct endocytotic absorption of these product phases by the intestinal microvillus membrane was found.
journal_name
J Lipid Resjournal_title
Journal of lipid researchauthors
Rigler MW,Honkanen RE,Patton JSsubject
Has Abstractpub_date
1986-08-01 00:00:00pages
836-57issue
8eissn
0022-2275issn
1539-7262journal_volume
27pub_type
杂志文章abstract：:Various detergents can be used to dissolve phospholipids, resulting in very narrow 31PNMR resonances. The resonances are well resolved, allowing identification and quantitative analysis of phospholipids in a mixture. The chemical shift depends strongly on pH, reflecting changes in the state of ionization of the phosph...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1979-03-01 00:00:00
abstract：:Lipoprotein lipase (LPL) and hepatic lipase (HL) mediate the hydrolysis of triglycerides and phospholipids present in circulating lipoprotein particles and are essential for normal lipid metabolism. Both enzymes have a similar primary amino acid structure and share requirements for intact catalytic, lipid binding, and...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1993-08-01 00:00:00
abstract：:Cholesterol 7α-hydroxylase (CYP7A1) is the first and rate-limiting enzyme in the conversion of cholesterol to bile acids in the liver. In addition to absorption and digestion of nutrients, bile acids play a critical role in the regulation of lipid, glucose, and energy homeostasis. We have backcrossed Cyp7a1(-/-) mice ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M064709
更新日期：2016-07-01 00:00:00
abstract：:Lymph fistula rats with either biliary fistula or pancreaticobiliary fistula were used to measure coenzyme A-independent mucosal cholesterol esterifying activity in the presence and absence of pancreatic exocrine secretion. Efficiency of pancreatic diversion was verified to minimize contamination of mucosal homogenate...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1981-01-01 00:00:00
abstract：:The sphingomyelin pathway is an important signal transduction system regulating various cellular functions. However, little is known about the effect of sphingomyelin metabolites on vasomotor function. We examined the vascular effects of sphingomyelin, sphingosine, and sphingomyelinase (SPMase) in vitro. In pig corona...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1996-07-01 00:00:00
abstract：:The fatty acid composition of human skin fibroblasts grown in 10% dialyzed fetal calf serum can be modified considerably by adding supplemental fatty acids to the culture medium. The degree of modification was dependent on the concentration of added fatty acid over the range tested, 2.5 X 10(-5) to 1 X 10(-4) M. At th...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1979-05-01 00:00:00
abstract：:Thus far, liver, intestine, heart, and placenta have been shown to secrete apolipoprotein (apo)B-containing lipoproteins. In the present study, we first investigated lipoproteins in human follicular fluid (FF), surrounding developing oocytes within the ovary, as well as in corresponding plasma samples (n = 12). HDL ch...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M005181
更新日期：2010-08-01 00:00:00
abstract：:Adipogenic differentiation is a highly regulated process that is necessary for metabolic homeostasis and nutrient sensing. The expression of PPARγ and the subsequent activation of adipogenic genes is critical for the process. In this study, we identified lanthionine synthetase C-like protein 2 (LanCL2) as a positive r...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M085274
更新日期：2018-08-01 00:00:00
abstract：:High density lipoproteins (HDL) were isolated by a chromatographic procedure and subsequently fractionated on a DEAE cellulose (DE-52) column. Four fractions were separated and analyzed for lipid and protein composition and molecular weight. During ion exchange chromatography, one of the four fractions consistently co...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1981-09-01 00:00:00
abstract：:The bile acid (BA) composition in mice is substantially different from that in humans. Chenodeoxycholic acid (CDCA) is an end product in the human liver; however, mouse Cyp2c70 metabolizes CDCA to hydrophilic muricholic acids (MCAs). Moreover, in humans, the gut microbiota converts the primary BAs, cholic acid and CDC...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.RA119000395
更新日期：2020-01-01 00:00:00
abstract：:Several recent reports have examined whether there is a correlation between the presence of some minor alleles of the highly polymorphic apolipoprotein B gene and atherosclerosis and premature heart disease. The present study extends this investigation. A high-resolution method was used to study the allele frequencies...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1990-04-01 00:00:00
abstract：:Autophagy is a catabolic process involved in maintaining energy and organelle homeostasis. The relationship between obesity and the regulation of autophagy is cell type specific. Despite adverse consequences of obesity on cardiac structure and function, the contribution of altered cardiac autophagy in response to fatt...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M055152
更新日期：2015-03-01 00:00:00
abstract：:Multiple changes in HDL metabolism occur during infection and inflammation that could potentially impair the antiatherogenic functions of HDL. Scavenger receptor class B type I (SR-BI) promotes cholesterol efflux from peripheral cells and mediates selective uptake of cholesteryl ester into hepatocytes, thereby playing...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：2001-10-01 00:00:00
abstract：:Consumption of industrially produced trans fatty acids (IP-TFA) has been positively associated with systemic markers of low-grade inflammation and endothelial dysfunction in cross-sectional studies, but results from intervention studies are inconclusive. Therefore, we conducted a 16 week double-blind parallel interven...
journal_title：Journal of lipid research
pub_type： 杂志文章,随机对照试验
doi：10.1194/jlr.M014738
更新日期：2011-10-01 00:00:00
abstract：:Extracted tissue phospholipid 31P NMR profiles, obtained from individual porcine lenses subjected to two preservation procedures (acetone desiccation and freeze-drying) and a perchloric acid-extraction procedure, were compared to those from freshly excised lens specimens. Each profile yielded quantitative data on 12 l...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
abstract：:It was the aim of this study to i) compare the effects of glucose and other hexoses with that of oleate on secretion of apolipoproteins (apos) A-I and B by HepG2 cells, and ii) document the effect of various metabolic inhibitors on the secretion of these apos in the absence or presence of extra glucose/oleate. i) The ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1995-08-01 00:00:00
abstract：:HDL plays crucial roles at multiple stages of the pathogenesis of atherosclerosis. AMP-activated protein kinase (AMPK) is a therapeutic candidate for the treatment of cardiovascular disease. However, the effect of AMPK activation on HDL functionality has not been established in vivo. We assessed the effects of pharmac...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M073270
更新日期：2017-08-01 00:00:00
abstract：:Genetic polymorphisms of apolipoprotein A-IV (apoA-IV) have been detected by isoelectric focusing of serum proteins. Because genetic variation in apoA-IV has significant effects on lipid risk factors, we used restriction enzyme isoform genotyping (restriction isotyping) to determine apoA-IV isoform genotypes at the DN...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1991-09-01 00:00:00
abstract：:Recent studies suggest that 7-dehydrocholesterol (7-DHC)-derived oxysterols play important roles in the pathophysiology of Smith-Lemli-Opitz syndrome (SLOS), a metabolic disorder that is caused by defective 3β-hydroxysterol-Δ(7)-reductase (DHCR7). Although 14 oxysterols have been identified as the primary products of ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M035733
更新日期：2013-04-01 00:00:00
abstract：:Lipoprotein metabolism can be studied by the analysis of lipoprotein production in cell culture. An inherent problem in such an analysis is the low concentration of lipoproteins in culture supernatants. The difficulty comes from the fact that the samples must be concentrated prior to any analysis. The concentrating me...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1995-10-01 00:00:00
abstract：:Subcellular localization of nonesterified cholesterol has been determined in normal human fibroblasts from cultures incubated with human low density lipoprotein (LDL). Nonesterified and esterified cholesterol content of fibroblasts, grown initially in the absence of cholesterol, increased significantly after a 1-hour ...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1982-11-01 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：: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：:The simultaneous exchange of (3h)tocopherol and (14C)cholesterol between rat plasma, rat plasma lipoproteins, and RBC was studied in vitro to compare quantitavely (a) the fractional exchange rates and (b) the half-times for isotope equilibration. In all incubations of RBC with plasma or with plasma lipoprotein fractio...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1975-01-01 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：:Purified liver plasma membranes were prepared from rats fed a high-fat, carbohydrate-free diet or a high-glucose, fat-free diet. Membranes from rats fed the high-fat diet bound significantly less 125I-labeled concanavalin A (Con A) than did those from rats fed the fat-free diets. The magnitude of the binding differenc...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1979-07-01 00:00:00
abstract：:A novel and rapid method for the detergent-mediated synthesis of protein-lipid complexes has been developed and has several advantages over detergent dialysis methods. This new method involves co-incubation of human apolipoprotein A-I (apoA-I), the major protein component of high density lipoproteins (HDL), and dipalm...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1988-03-01 00:00:00
abstract：:Paraoxonases (PONs) are a small family of antioxidant enzymes whose antiatherogenic activity is well known. The aim of the present study was the evaluation of the effects of moderate aerobic training on their expression using a rat model. In order to discriminate between PON1 and PON3 enzymatic activity, we took advan...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：10.1194/jlr.M800493-JLR200
更新日期：2009-10-01 00:00:00
abstract：:A report on the effects of primary bile acid ingestion alone or in combination with plant sterols on serum cholesterol levels, biliary lipid secretion, and bile acid metabolism. Biliary bile acid and cholesterol secretion were measured in four patients with type IIa hypercholesterolemia before and after randomized tre...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1979-01-01 00:00:00
abstract：:The technique of short bed--continuous development chromatography has been utilized to increase the separation of glycosphingolipids on high performance thin-layer chromatography plates. The theoretical goal of increasing separation of bands by decreasing solvent strength was achieved within a practical time span as a...
journal_title：Journal of lipid research
pub_type： 杂志文章
doi：
更新日期：1986-01-01 00:00:00
