Aspects of hepatic cholesterol metabolism in normal and dystrophic chicken embryos

1983 ◽  
Vol 61 (6) ◽  
pp. 378-386 ◽  
Author(s):  
D. E. Kuhn ◽  
D. M. Logan
Keyword(s):  
Total Cholesterol ◽  
Free Cholesterol ◽  
Cholesterol Metabolism ◽  
Cholesterol Content ◽  
Normal Embryo ◽  
Total Protein Content ◽  
Cholesterol Esters ◽  
Hepatic Cholesterol ◽  
Chicken Embryos ◽  
Dystrophic Chicken

Several aspects of hepatic cholesterol metabolism have been studied in normal and dystrophic chicken embryos (12 days in ovo). Dystrophic embryo livers weigh the same and have the same total protein content as their normal counterparts. However, the total cholesterol content of dystrophic embryo livers is significantly decreased compared with the content of normal embryo livers. This decrease in total cholesterol is due mainly to a large decrease in the amount of cholesterol esters, although the free cholesterol content is also decreased. The proportions of free cholesterol and cholesterol esters are 43 and 57%, respectively, in normal embryo livers, but this proportion is essentially reversed in dystrophic embryo livers (i.e., 56 and 44%). The decreased total cholesterol content of dystrophic embryo livers is not apparently due to a decrease in the rate of free cholesterol de novo biosynthesis or to a decrease in the rate of free cholesterol esterification. However, the decrease in cholesterol ester content may be due to an increase in the rate of its hydrolysis, as a result of increased levels of sterol ester hydrolase in dystrophic livers. These data are consistent with the proposal that membranes in dystrophic tissues are altered as a result of altered cholesterol metabolism and utilization.

EFFECT OF HYPOPHYSECTOMY ON CHOLESTEROL METABOLISM IN THE TESTES OF RATS AND MICE

1972 ◽  
Vol 52 (2) ◽  
pp. 321-326 ◽  
Author(s):  
A. A. HAFIEZ ◽  
A. BARTKE
Keyword(s):  
Total Cholesterol ◽  
De Novo ◽  
Cholesterol Metabolism ◽  
Cholesterol Content ◽  
Testicular Tissue ◽  
Testis Weight ◽  
Acetate Incorporation ◽  
Rats And Mice

SUMMARY Increased synthesis de novo of cholesterol by testes of rats and mice was found to be a contributing factor in the increased testicular cholesterol content after hypophysectomy. This was shown by increased [1-14C]acetate incorporation in vitro into free and esterified cholesterol by testicular tissue from rats and mice hypophysectomized 3 weeks earlier, as compared with intact controls. In mice, testicular cholesterol content was significantly increased 1 day after hypophysectomy at which time there was no change in the testis weight. Three weeks after the operation there was a significant decrease in testis weight and a significant increase in the concentration of free, esterified and total cholesterol as well as in the percentage of esterified fraction. These changes were even more pronounced 1 month later.

Effect of Pluronic L81, a hydrophobic surfactant, on intestinal mucosal cholesterol homeostasis

1991 ◽  
Vol 261 (2) ◽  
pp. G256-G262 ◽  
Author(s):  
C. Pool ◽  
D. F. Nutting ◽  
W. J. Simmonds ◽  
P. Tso
Keyword(s):  
Total Cholesterol ◽  
Intestinal Mucosa ◽  
Free Cholesterol ◽  
Sodium Taurocholate ◽  
Cholesterol Content ◽  
Cholesterol Homeostasis ◽  
Triglyceride Rich Lipoprotein ◽  
Specific Activities ◽  
Chylomicron Formation

Addition of triglyceride and phospholipid to sodium taurocholate when chylomicron output was blocked by L81 did not increase lymphatic total cholesterol output or mucosal unesterified (UC) content more than with sodium taurocholate alone, but mucosal esterified cholesterol (CE) was increased slightly. In these animals with defective chylomicron formation, excess cholesterol accumulated in the intestinal mucosa mainly as CE. The mucosal cholesterol content of animals with normal chylomicron transport expanded during cholesterol and triglyceride absorption, and the expansion led to increased lymphatic secretion of CE. These animals accumulated significantly less CE in their mucosa than did rats treated with L81, but had about the same amount of mucosal UC. However, the overall uptake of cholesterol from the lumen, as determined by either radioactivity or mass of cholesterol in mucosa and lymph, was significantly less in the L81 rats. Also, more radioactive cholesterol remained in the lumen of the L81-treated rats. Finally, the data on specific activities of free and esterified cholesterol showed that the mucosal cholesterol derived from the lumen does not mix evenly with the free cholesterol pool in the enterocytes and is preferentially esterified for export in lymph as triglyceride-rich lipoprotein.

Automated enzymic measurement of total cholesterol in serum.

1978 ◽  
Vol 24 (1) ◽  
pp. 108-114 ◽  
Author(s):  
G S Rautela ◽  
R J Liedtke
Keyword(s):  
Hydrogen Peroxide ◽  
Total Cholesterol ◽  
Response Surface ◽  
Computer Analysis ◽  
Free Cholesterol ◽  
Cholesterol Oxidase ◽  
Cholesterol Esters ◽  
Direct Proportion ◽  
Analytical Test ◽  
Response Surface Designs

Abstract We describe a completely automated enzymic system for measuring total cholesterol in serum. All reagents are contained in an analytical test pack and the test is performed on Du Pont's Automatic Clinical Analyzer (aca), which mixes the sample (20 microliter) and reagents and performs the necessary absorbance measurements and calculations. In the procedure, cholesterol oxidase oxidizes free cholesterol. The oxidation step produces cholest-4-en-3-one and hydrochloride peroxidesterase hydrolyzes cholesterol esters and cholesterol in direct proportion to the amount of cholesterol present. N,N-Diethylaniline hydrochloride and 4-aminoantipyrine react with the hydrogen peroxide to produce a quinoneimine dye (lambda max = 553 nm). Interacting reagents have been optimized simultaneously (coöptimization) utilizing response surface designs coupled with computer analysis of the data. Reagent efficiency is high and analytical performance reliable.

scholarly journals Lipids analysis in hemolymph of African giant Achatina fulica (Bowdich, 1822) exposed to different photoperiods

2010 ◽  
Vol 70 (1) ◽  
pp. 129-134 ◽  
Author(s):  
D. Lustrino ◽  
VM. Tunholi-Alves ◽  
VM. Tunholi ◽  
MP. Marassi ◽  
J. Pinheiro
Keyword(s):  
Total Cholesterol ◽  
Cell Membranes ◽  
Cholesterol Metabolism ◽  
Cholesterol Biosynthesis ◽  
Cholesterol Content ◽  
Achatina Fulica ◽  
Negative Relation ◽  
Post Exposure ◽  
Lipids Analysis ◽  
Lipids Metabolism

The influence of different photophases (0, 6, 12, 18 and 24 hours) on the triglycerides and total cholesterol contents in the hemolymph of A. fulica was evaluated, since there is no information in the literature about the influence of this factor on lipids metabolism in mollusks. After 2 and 4 weeks of exposure the snails were dissected. The cholesterol content at the 2nd and 4th weeks post exposure only varied significantly in the groups exposed at 24 hours and 0 hour of photophase, respectively. Probably, such increase may be a result of a rise in cholesterol biosynthesis and/or remodelling of cell membranes. There were no significant differences among the content of triglycerides in the snails exposed to 6, 12, 18 and 24 hours of photophase during two weeks. The snails exposed to intermediate photophase (6 and 12 hours) had the triglycerides content increased, ranging over values near to those observed in the group exposed to 0 hour. Results showed that triglycerides metabolism in A. fulica are more influenced by photoperiod than cholesterol metabolism. A negative relation is maintained between the triglycerides content in the hemolymph and the different photophases, with lower mobilisation of triglycerides under shorter photophases.

scholarly journals IL-13-driven alterations in hepatic cholesterol handling contributes to hypercholesterolemia in a rat model of minimal change disease

2020 ◽  
Vol 134 (2) ◽  
pp. 225-237 ◽  
Author(s):  
Lauretta D. Low ◽  
Liangjian Lu ◽  
Chang-Yien Chan ◽  
Jinmiao Chen ◽  
Henry H. Yang ◽  
...  
Keyword(s):  
Total Cholesterol ◽  
Rat Model ◽  
Minimal Change Disease ◽  
Cholesterol Metabolism ◽  
Rat Hepatocytes ◽  
Minimal Change ◽  
Luciferase Assay ◽  
Hepatic Cholesterol ◽  
Plasma Total Cholesterol ◽  
Rat Primary Hepatocytes

Abstract Circulating factors have been implicated in the pathogenesis of minimal change disease (MCD), and may have direct effects on cholesterol metabolism. This study investigated the pathogenesis of hypercholesterolemia in an IL-13 overexpression rat model of MCD prior to the onset of proteinuria, so as to establish the direct contribution of IL-13, especially with regard to hepatic cholesterol handling. In this model of MCD, the temporal relationship between hypercholesterolemia and proteinuria was first identified. Plasma proprotein convertase subtilisin/kexin type 9 (Pcsk9) and liver ATP-binding cassette sub-family G member 5 (Abcg5) were measured using ELISA. Liver Ldlr and liver X receptor alpha (Lxra) were quantified with Western blot. Abcg5-mediated cholesterol efflux in IL-13-stimulated rat primary hepatocytes was measured using taurocholate as cholesterol acceptor. The role of Lxra was validated using a luciferase assay in Lxre-luciferase-transfected IL-13-stimulated hepatocytes. IL-13-transfected rats developed hypercholesterolemia prior to proteinuria, with 35% of rats hypercholesterolemic but only 11% proteinuric by Day 20 (P = 0.04). These pre-proteinuric hypercholesterolemic rats showed elevations in total and LDL-cholesterol, but not hypertriglyceridemia or hepatic steatosis. The hypercholesterolemia was associated with increased hepatic Pcsk9 synthesis and enhanced circulating Pcsk9 levels, which correlated strongly with plasma total cholesterol (r = 0.73, P<0.001). The hypercholesterolemia was also contributed by decreased Abcg5 expression and activity, due to reduced Lxra expression. Lxra expression correlated with plasma total cholesterol levels (r = −0.52, P = 0.01), and overexpression of pLxra in rat hepatocytes abrogated the IL-13-mediated down-regulation of Lxre-driven gene expression. In conclusion, we have shown that IL-13 induced changes in hepatic cholesterol handling in a cytokine-induced rat model of MCD, resulting in hypercholesterolemia which can precede the onset of proteinuria.

scholarly journals The origin and destiny of cholesterol in the animal organism. Part VIII.—On the cholesterol content of the liver of rabbits under various diets and during inanition

1912 ◽  
Vol 84 (574) ◽  
pp. 461-470 ◽  
Keyword(s):  
Bile Salts ◽  
Free Cholesterol ◽  
Waste Product ◽  
Cholesterol Content ◽  
Blood Stream ◽  
Cholesterol Esters ◽  
Life Process ◽  
Animal Organism ◽  
Working Hypothesis

In parts V and VII of this series of papers evidence was brought forward to show that when cholesterol, free and in the form of esters, is given with the food of rabbits, some is absorbed and finds its way into the blood stream, and that an increase of both free cholesterol and cholesterol esters takes place in the blood. This result affords support to the working hypothesis with regard to the origin and destiny of cholesterol in the animal organism, which we were led to formulate in an earlier paper, viz., that cholesterol is a constituent constantly present in all cells are broken down in the life process the cholestrol is not excreted as a waste product but is utilised in the formation of new cells. A function of the liver is to break down dead cells, e. g ., blood corpuscles, and eliminate their cholesterol in the bile. After the bile has been poured into the intestine in the processes of digestion, the cholesterol is re-absorbed, possibly in the form of esters, along with the bile salts and is carried in the blood stream to the various centres and tissues for re-incorporation into the constitution of new cells.

Determination of Total and Esterified Cholesterol in Serum

1966 ◽  
Vol 12 (11) ◽  
pp. 739-747 ◽  
Author(s):  
Charles Sobel ◽  
Alberto Fernandez
Keyword(s):  
Total Cholesterol ◽  
Free Cholesterol ◽  
Serum Lipids ◽  
Solvent Mixture ◽  
Solvent Composition ◽  
Cholesterol Esters ◽  
Simple Method ◽  
Reference Procedure

Abstract A simple method for the determination of total and esterified cholesterol is described. Serum lipids are extracted into a solvent mixture and aliquots of the extract are analyzed directly for free and total cholesterol by the Zlatkis reaction. Esterified cholesterol is calculated by difference. Free cholesterol is determined under conditions of temperature and solvent composition such that the cholesterol esters do not react. The method yields quantitative recoveries of free and esterified cholesterol from serum. Data are presented on the precision of the method, and on results of a comparison with the reference procedure of Sperry and Webb.

scholarly journals Effect of the combinations between pea proteins and soluble fibres on cholesterolaemia and cholesterol metabolism in rats

2013 ◽  
Vol 110 (8) ◽  
pp. 1394-1401 ◽  
Author(s):  
Cinzia Parolini ◽  
Stefano Manzini ◽  
Marco Busnelli ◽  
Elena Rigamonti ◽  
Marta Marchesi ◽  
...  
Keyword(s):  
Functional Foods ◽  
Cholesterol Metabolism ◽  
Plasma Cholesterol ◽  
Cholesterol Content ◽  
Cholesterol Homeostasis ◽  
Hepatic Cholesterol ◽  
Cholesterol Reduction ◽  
Apple Pectin ◽  
Expression Of Genes ◽  
Pea Proteins

Many functional foods and dietary supplements have been reported to be beneficial for the management of dyslipidaemia, one of the major risk factors for CVD. Soluble fibres and legume proteins are known to be a safe and practical approach for cholesterol reduction. The present study aimed at investigating the hypocholesterolaemic effect of the combinations of these bioactive vegetable ingredients and their possible effects on the expression of genes regulating cholesterol homeostasis. A total of six groups of twelve rats each were fed, for 28 d, Nath's hypercholesterolaemic diets, differing in protein and fibre sources, being, respectively, casein and cellulose (control), pea proteins and cellulose (pea), casein and oat fibres (oat), casein and apple pectin (pectin), pea proteins and oat fibres (pea+oat) and pea proteins and apple pectin (pea+pectin). Administration of each vegetable-containing diet was associated with lower total cholesterol concentrations compared with the control. The combinations (pea+oat and pea+pectin) were more efficacious than fibres alone in modulating cholesterolaemia ( − 53 and − 54 %, respectively, at 28 d; P< 0·005). In rats fed the diets containing oat fibres or apple pectin, alone or in combination with pea proteins, a lower hepatic cholesterol content (P< 0·005) and higher hepatic mRNA concentrations of CYP7A1 and NTCP were found when compared with the control rats (P< 0·05). In summary, the dietary combinations of pea proteins and oat fibres or apple pectin are extremely effective in lowering plasma cholesterol concentrations in rats and affect cellular cholesterol homeostasis by up-regulating genes involved in hepatic cholesterol turnover.

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