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.

Gender effects of tall oil versus soybean phytosterols as cholesterol-lowering agents in hamsters

1998 ◽  
Vol 76 (7-8) ◽  
pp. 780-787 ◽  
Author(s):  
Fady Y Ntanios ◽  
Diane E MacDougall ◽  
Peter JH Jones
Keyword(s):  
Total Cholesterol ◽  
Cholesterol Level ◽  
Cholesterol Metabolism ◽  
Total Cholesterol Level ◽  
Cholesterol Biosynthesis ◽  
Gender Effects ◽  
Plasma Total Cholesterol ◽  
Tall Oil ◽  
Cholesterol Lowering ◽  
Plasma Total Cholesterol Level

To examine the effect of gender on the mechanisms of action of phytosterols extracted from tall oil (TO) and soybean (SB) on cholesterol and phytosterol metabolism, male and female hamsters were fed cholesterol-enriched diets containing 0.5 or 1% (w/w) TO or SB phytosterols for 90 days. Plasma lipoprotein cholesterol profile and tissue phytosterol and cholesterol biosynthesis levels were determined. Mean plasma total-cholesterol level in females fed 1% (w/w) SB was reduced (p < 0.05) by 44%, while in males it was lowered (p < 0.05) by 25% compared with their respective controls. Moreover, mean plasma total-cholesterol level was reduced (p < 0.05) in male hamsters by -31% and female hamsters by -32% when fed 1% (w/w) TO. Cholesterol biosynthesis was higher (p < 0.05) by twofold in groups fed TO at 0.5 and 1% (w/w) concentrations, compared with SB. Hamsters fed TO at 0.5 and 1% (w/w) levels also had higher (p < 0.05) hepatic and enterocytic campesterol contents than SB-fed animals. These findings demonstrate gender differences in cholesterol metabolism in TO- and SB-fed hamsters. The results suggest that TO, conversely to SB phytosterol, is a more effective cholesterol-lowering agent in male, but not as much in female, hamsters, over a feeding period of 90 days.Key words: phytosterols, cholesterol, sitosterol, sitostanol, gender, hamster.

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.

scholarly journals Gene-environment interactions reveal a homeostatic role for cholesterol metabolism during dietary folate perturbation in mice

2008 ◽  
Vol 35 (2) ◽  
pp. 182-190 ◽  
Author(s):  
Toshimori Kitami ◽  
Renee Rubio ◽  
William O'Brien ◽  
John Quackenbush ◽  
Joseph H. Nadeau
Keyword(s):  
Gene Expression ◽  
Total Cholesterol ◽  
Birth Defects ◽  
Metabolic Pathways ◽  
Cholesterol Metabolism ◽  
Cholesterol Biosynthesis ◽  
Inbred Strains ◽  
Serum Folate ◽  
Folate Supplementation ◽  
Dietary Folate

Dietary folate supplementation can dramatically reduce the severity and incidence of several common birth defects and adult diseases that are associated with anomalies in homocysteine and folate metabolism. The common polymorphisms that adversely affect these metabolic pathways do not fully account for the particular birth defects and adult diseases that occur in at-risk individuals. To test involvement of folate, homocysteine, and other pathways in disease pathogenesis and treatment response, we analyzed global and pathway-specific changes in gene expression and levels of selected metabolites after depletion and repletion of dietary folate in two genetically distinct inbred strains of mice. Compared with the C57BL/6J strain, A/J showed greater homeostatic response to folate perturbation by retaining a higher serum folate level and minimizing global gene expression changes. Remarkably, folate perturbation led to systematic strain-specific differences only in the expression profile of the cholesterol biosynthesis pathway and to changes in levels of serum and liver total cholesterol. By genetically increasing serum and liver total cholesterol levels in APOE-deficient mice, we modestly but significantly improved folate retention during folate depletion, suggesting that homeostasis among the homocysteine, folate and cholesterol metabolic pathways contributes to the beneficial effects of dietary folate supplementation.

scholarly journals Brain Cholesterol Metabolism and Its Defects: Linkage to Neurodegenerative Diseases and Synaptic Dysfunction

Acta Naturae ◽  
2016 ◽  
Vol 8 (1) ◽  
pp. 58-73 ◽  
Author(s):  
A. M. Petrov ◽  
M. R. Kasimov ◽  
A. L. Zefirov
Keyword(s):  
Plasma Membrane ◽  
Synaptic Transmission ◽  
Neurodegenerative Diseases ◽  
Plasma Membranes ◽  
Cholesterol Metabolism ◽  
Cholesterol Biosynthesis ◽  
Cholesterol Content ◽  
Brain Cholesterol ◽  
Cholesterol Biosynthetic Pathway ◽  
Niemann Pick

Cholesterol is an important constituent of cell membranes and plays a crucial role in the compartmentalization of the plasma membrane and signaling. Brain cholesterol accounts for a large proportion of the bodys total cholesterol, existing in two pools: the plasma membranes of neurons and glial cells and the myelin membranes . Cholesterol has been recently shown to be important for synaptic transmission, and a link between cholesterol metabolism defects and neurodegenerative disorders is now recognized. Many neurodegenerative diseases are characterized by impaired cholesterol turnover in the brain. However, at which stage the cholesterol biosynthetic pathway is perturbed and how this contributes to pathogenesis remains unknown. Cognitive deficits and neurodegeneration may be associated with impaired synaptic transduction. Defects in cholesterol biosynthesis can trigger dysfunction of synaptic transmission. In this review, an overview of cholesterol turnover under physiological and pathological conditions is presented (Huntingtons, Niemann-Pick type C diseases, Smith-Lemli-Opitz syndrome). We will discuss possible mechanisms by which cholesterol content in the plasma membrane influences synaptic processes. Changes in cholesterol metabolism in Alzheimers disease, Parkinsons disease, and autistic disorders are beyond the scope of this review and will be summarized in our next paper.

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.

The Effect of Oxidized Cholesterol on the Aorta of Rabbits- Scanning Electron Microscopic Observations

1982 ◽  
Vol 40 ◽  
pp. 340-341
Author(s):  
S. K. Pena ◽  
C. B. Taylor ◽  
J. Hill ◽  
J. Safarik
Keyword(s):  
Cholesterol Biosynthesis ◽  
Cholesterol Content ◽  
Arterial Injury ◽  
Electron Microscopic ◽  
Aortic Smooth Muscle ◽  
Oxidized Cholesterol ◽  
Initial Event ◽  
Membrane Structure And Function ◽  
Scanning Electron Microscopic ◽  
And Function

Introduction: Oxidized cholesterol derivatives have been demonstrated in various cell cultures to be very potent inhibitors of 3-hvdroxy-3- methylglutaryl Coenzyme A reductase which is a principle regulator of cholesterol biosynthesis in the cell. The cholesterol content in the cells exposed to oxidized cholesterol was found to be markedly decreased. In aortic smooth muscle cells, the potency of this effect was closely related to the cytotoxicity of each derivative. Furthermore, due to the similarity of their molecular structure to that of cholesterol, these oxidized cholesterol derivatives might insert themselves into the cell membrane, alter membrane structure and function and eventually cause cell death. Arterial injury has been shown to be the initial event of atherosclerosis.

Cholesterol in Serum and Lipoprotein Fractions

1956 ◽  
Vol 2 (3) ◽  
pp. 145-159 ◽  
Author(s):  
Joseph T Anderson ◽  
Ancel Keys
Keyword(s):  
Human Serum ◽  
Total Cholesterol ◽  
Filter Paper ◽  
Room Temperature ◽  
Paper Electrophoresis ◽  
Cholesterol Content ◽  
Intraindividual Variability ◽  
Detailed Data ◽  
The Stability ◽  
Source Of Error

Abstract 1. Methods are described for the separation, by paper electrophoresis and by cold ethanol, of α- and β-lipoproteins in 0.1 ml. of serum, with subsequent analysis of cholesterol in the separated portions. 2. It is shown that both methods of separation yield separated fractions containing substantially the same amounts of cholesterol. 3. Detailed data are given on the errors of measurement for total cholesterol and for cholesterol in the separated lipoprotein fractions. 4. Studies are reported on the stability of cholesterol in stored serum and on paper electrophoresis strips. It is shown that simple drying on filter paper causes no change in cholesterol content and yields a product that is stable for many weeks at ordinary room temperature. 5. The sources of variability in human serum cholesterol values are examined and it is shown that spontaneous intraindividual variability is a much greater source of error than the errors of measurement with these methods.

scholarly journals Abnormal brain cholesterol homeostasis in Alzheimer’s disease—a targeted metabolomic and transcriptomic study

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Vijay R. Varma ◽  
H. Büşra Lüleci ◽  
Anup M. Oommen ◽  
Sudhir Varma ◽  
Chad T. Blackshear ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Brain Tissue ◽  
Cholesterol Metabolism ◽  
Cholesterol Biosynthesis ◽  
Cholesterol Homeostasis ◽  
Transcriptomic Data ◽  
Brain Cholesterol ◽  
Cholesterol Levels

AbstractThe role of brain cholesterol metabolism in Alzheimer’s disease (AD) remains unclear. Peripheral and brain cholesterol levels are largely independent due to the impermeability of the blood brain barrier (BBB), highlighting the importance of studying the role of brain cholesterol homeostasis in AD. We first tested whether metabolite markers of brain cholesterol biosynthesis and catabolism were altered in AD and associated with AD pathology using linear mixed-effects models in two brain autopsy samples from the Baltimore Longitudinal Study of Aging (BLSA) and the Religious Orders Study (ROS). We next tested whether genetic regulators of brain cholesterol biosynthesis and catabolism were altered in AD using the ANOVA test in publicly available brain tissue transcriptomic datasets. Finally, using regional brain transcriptomic data, we performed genome-scale metabolic network modeling to assess alterations in cholesterol biosynthesis and catabolism reactions in AD. We show that AD is associated with pervasive abnormalities in cholesterol biosynthesis and catabolism. Using transcriptomic data from Parkinson’s disease (PD) brain tissue samples, we found that gene expression alterations identified in AD were not observed in PD, suggesting that these changes may be specific to AD. Our results suggest that reduced de novo cholesterol biosynthesis may occur in response to impaired enzymatic cholesterol catabolism and efflux to maintain brain cholesterol levels in AD. This is accompanied by the accumulation of nonenzymatically generated cytotoxic oxysterols. Our results set the stage for experimental studies to address whether abnormalities in cholesterol metabolism are plausible therapeutic targets in AD.

scholarly journals Human Lanosterol 14-Alpha Demethylase (CYP51A1) Is a Putative Target for Natural Flavonoid Luteolin 7,3′-Disulfate

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2237
Author(s):  
Leonid Kaluzhskiy ◽  
Pavel Ershov ◽  
Evgeniy Yablokov ◽  
Tatsiana Shkel ◽  
Irina Grabovec ◽  
...  
Keyword(s):  
Cholesterol Metabolism ◽  
Cholesterol Biosynthesis ◽  
Clinical Importance ◽  
Optical Biosensor ◽  
Water Soluble ◽  
Soluble Form ◽  
Redox Partner ◽  
Access Channel ◽  
Kd Values ◽  
Key Steps

Widespread pathologies such as atherosclerosis, metabolic syndrome and cancer are associated with dysregulation of sterol biosynthesis and metabolism. Cholesterol modulates the signaling pathways of neoplastic transformation and tumor progression. Lanosterol 14-alpha demethylase (cytochrome P450(51), CYP51A1) catalyzes one of the key steps in cholesterol biosynthesis. The fairly low somatic mutation frequency of CYP51A1, its druggability, as well as the possibility of interfering with cholesterol metabolism in cancer cells collectively suggest the clinical importance of CYP51A1. Here, we show that the natural flavonoid, luteolin 7,3′-disulfate, inhibits CYP51A1 activity. We also screened baicalein and luteolin, known to have antitumor activities and low toxicity, for their ability to interact with CYP51A1. The Kd values were estimated using both a surface plasmon resonance optical biosensor and spectral titration assays. Unexpectedly, in the enzymatic activity assays, only the water-soluble form of luteolin—luteolin 7,3′-disulfate—showed the ability to potently inhibit CYP51A1. Based on molecular docking, luteolin 7,3′-disulfate binding suggests blocking of the substrate access channel. However, an alternative site on the proximal surface where the redox partner binds cannot be excluded. Overall, flavonoids have the potential to inhibit the activity of human CYP51A1 and should be further explored for their cholesterol-lowering and anti-cancer activity.

Relationships between Serum Saturated Fatty Acids and Serum Total Cholesterol and HDL-Cholesterol in Humans

1994 ◽  
Vol 31 (3) ◽  
pp. 240-244 ◽  
Author(s):  
Teruo Nagaya ◽  
Ken-Ichi Nakaya ◽  
Akemi Takahashi ◽  
Izumi Yoshida ◽  
Yoshinari Okamoto
Keyword(s):  
Body Mass Index ◽  
Fatty Acids ◽  
Multivariate Analysis ◽  
Total Cholesterol ◽  
Cholesterol Metabolism ◽  
Saturated Fatty Acids ◽  
Hdl Cholesterol ◽  
Significant Relation ◽  
Men And Women ◽  
Fa Composition

To investigate the effects of serum saturated fatty acids (FAs) on human cholesterol metabolism, total-cholesterol (T-C), HDL-cholesterol (HDL-C), T-C/HDL-C ratio, and FA composition [myristic acid (MA, 14:0), palmitic acid (PA, 16:0) and stearic acid (SA, 18:0)] were determined in serum from 115 men and 120 women (20–70 years old). MA, PA and SA were expressed as percentages of serum total FAs. Using multivariate analysis to account for the confounding effects of age, body mass index, drinking, and smoking it was found that SA was negatively correlated with T-C and T-C/HDL-C ratio in both men and women. In men MA was negatively correlated with HDL-C, and in women SA was positively correlated with HDL-C. Although PA was the major component of serum saturated FAs, PA had no significant relation to any cholesterol indices in either sex. These results suggest that serum MA may aggravate and serum SA may improve cholesterol metabolism, thereby influencing the risk for ischaemic heart disease.

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