Catabolism of human very-low-density lipoproteins in monkeys: The appearance of human very-low-density lipoprotein peptides in monkey high-density lipoproteins

1972 ◽  
Vol 270 (3) ◽  
pp. 426-432 ◽  
Author(s):  
G. Schonfeld ◽  
C.L. Gulbrandsen ◽  
R.B. Wilson ◽  
R.S. Lees
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Density Lipoproteins ◽  
High Density ◽  
High Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Very Low Density Lipoproteins

scholarly journals Stimulation of triacylglycerol synthesis in rat adipocytes by plasma very-low-density lipoproteins

1978 ◽  
Vol 176 (1) ◽  
pp. 169-174 ◽  
Author(s):  
P Thomopoulos ◽  
M Berthelier ◽  
D Lagrange ◽  
M J Chapman ◽  
M H Laudat
Keyword(s):  
Fatty Acids ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Density Lipoproteins ◽  
High Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Rat Adipocytes ◽  
Triacylglycerol Synthesis

The effect of human plasma lipoproteins on lipogenesis from glucose has been studied in isolated rat adipocytes. The very-low-density lipoproteins increased lipogenesis specifically, whereas low-density lipoproteins and high-density lipoproteins were without effect. Such stimulation could be reproduced with partially delipidated very-low-density lipoproteins. Nod-esterified fatty acids and glycerol were also without effect. Pretreatment of the adipocytes with trypsin did not alter the effect of very-low-density lipoprotein. The presence of Ca2+ was required for the full activation of lipogenesis. The synthesis of acylglycerol fatty acids and of acylglycerol glycerol were equally increased. The effect of very-low-density lipoprotein was not additive to that of insulin. It is suggested that very-low-density lipoprotein may directly stimulate lipogenesis in fat-cells, particularly in states when the lipoproteins are present at high concentration in the circulation.

scholarly journals Repercussões da cirurgia bariátrica na qualidade de vida, no perfil bioquímico e na pressão arterial de pacientes com obesidade mórbida

2018 ◽  
Vol 25 (3) ◽  
pp. 284-293
Author(s):  
Lucas Silva Franco de Oliveira ◽  
Mauro Lúcio Mazini Filho ◽  
Juliana Brandão Pinto de Castro ◽  
Henrique Menezes Touguinha ◽  
Patrick Costa Ribeiro Silva ◽  
...  
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Density Lipoproteins ◽  
High Density ◽  
High Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Sf 36

RESUMO A indicação da cirurgia bariátrica (CB) para perda de peso e redução de comorbidades associadas à obesidade é crescente. O objetivo do presente estudo foi analisar as repercussões da CB na qualidade de vida (QV), no perfil bioquímico e na pressão arterial (PA) de indivíduos obesos mórbidos em três momentos distintos: um mês antes, três meses depois e seis meses após a CB. Participaram da pesquisa 42 indivíduos com obesidade mórbida do programa de CB de um hospital da cidade de Juiz de Fora - MG, os quais foram aleatoriamente divididos em grupo intervenção (GI, n=21) e grupo controle (GC, n=21). O GI sofreu intervenção cirúrgica e o GC foi orientado a manter os afazeres diários usuais durante todo período do estudo, além de receberem acompanhamento nutricional. Foram avaliados a QV, o perfil bioquímico e a PA através do instrumento SF-36, do exame laboratorial de sangue obtido no prontuário dos pacientes e do esfigmomanômetro e estetoscópio, respectivamente. Os resultados demonstraram redução nas variáveis bioquímicas High-density lipoproteins (HDL), Low-density lipoproteins (LDL), Very Low-Density Lipoprotein (VLDL), colesterol, triglicerídeos, hemoglobina glicada, glicose, pressão arterial sistólica e pressão arterial diastólica no GI, após 6 meses de cirurgia. Houve melhora significativa nas variáveis relacionadas à QV, exceto nos aspectos emocionais. Conclui-se que a CB pode repercutir positivamente na maioria dos domínios da QV, na melhora do perfil bioquímico e na PA de pacientes obesos mórbidos após 3 e 6 meses de CB.

The interaction of lipolysis products of very low density lipoprotein with plasma high density lipoprotein (HDL): perfusate HDL with plasma HDL subfractions

1987 ◽  
Vol 65 (3) ◽  
pp. 252-260 ◽  
Author(s):  
S. P. Tam ◽  
W. C. Breckenridge
Keyword(s):  
Particle Size ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
High Density ◽  
Molar Ratio ◽  
High Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Hdl Subfractions ◽  
Apo E

The nature of the interaction of high density lipoproteins (HDL), formed during lipolysis of human very low density lipoprotein (VLDL) by perfused rat heart, with subfractions of human plasma HDL was investigated. Perfusate HDL, containing apoliproproteins (apo) E, C-II, and C-III but no apo A-I or A-II, was incubated with a subfraction of HDL (HDL-A) containing apo A-I and A-II, but devoid of apo C-II, C-III, and E. The products of the incubation were resolved by heparin-Sepharose or hydroxylapatite chromatography under conditions which allowed the resolution of the initial HDL-A and perfusate HDL. The fractions were analyzed for apolipoprotein content and lipid composition and assessed for particle size by electron microscopy. Following the incubation, the apo-E-containing lipoproteins were distinct from perfusate HDL since they contained apo A-I as a major component and apo C-II and C-III in reduced proportions. However, the HDL-A fraction contained apo C-II and C-III as major constituents. Associated with these changes in apolipoprotein composition, the apo-E-rich lipoproteins acquired cholesteryl ester from the HDL-A fraction and lost phospholipid to the HDL-A fraction. The HDL-A fraction maintained a low unesterified cholesterol/phospholipid molar ratio (0.23), while the apo-E-containing lipoproteins possessed a high ratio (0.75) characteristic of the perfusate HDL. The particle size of apo-E-containing lipoproteins (138.9 ± 22.5 Å; 1 Å = 0.1 nm) was larger than the initial HDL-A (126.5 ± 17.6 Å) or the new HDL-A-like fraction (120.9 ± 17.4 Å) obtained following incubation with perfusate HDL. It is concluded that incubation of perfusate HDL containing apo E, C-II, and C-III with plasma HDL subfractions results in the acquisition of apo A-I and cholesteryl esters by the apo-E-containing perfusate HDL and the loss of apo C-II, C-III, and phospholipid to the plasma HDL-A fraction. The process does not appear to be due to fusion of the particles, since the apo-E-containing lipoproteins maintain a cholesterol/phospholipid ratio distinct from the HDL-A fraction. The data provide evidence for a potential mechanism for the formation of HDL-E, an apo-E-containing lipoprotein of HDL size and density, through lipolysis of VLDL.

Insufficient accuracy and specificity of polyanion precipitation methods for quantifying low-density lipoproteins

1990 ◽  
Vol 36 (12) ◽  
pp. 2109-2113 ◽  
Author(s):  
R Siekmeier ◽  
W März ◽  
W Gross
Keyword(s):  
Fatty Acids ◽  
Dextran Sulfate ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Low Density Lipoproteins ◽  
High Density Lipoproteins ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Nonesterified Fatty Acids ◽  
High Concentrations

Abstract Recently, polyanion precipitation assays for low-density lipoprotein (LDL)-cholesterol have been found to underestimate their analyte in normolipidemic samples (Siekmeier et al., Clin Chim Acta 1988;177:221-30). Therefore, accuracy, specificity, and interference by nonesterified fatty acids have been studied for three precipitants (obtained by heparin, dextran sulfate, or polyvinyl sulfate precipitation). At normal concentrations of LDL, precipitation is incomplete, whereas it is nearly quantitative at high concentrations of LDL. The polyvinyl sulfate reagent markedly responds to variations in the amount of non-LDL protein present in the precipitation mixture. In the dextran sulfate and the polyvinyl sulfate method, but not in the heparin method, the percentages of LDL precipitated notably increase as the concentration of the polyanion compound is decreased. In either assay, very-low-density lipoproteins, but not high-density lipoproteins, are significantly coprecipitated (dextran sulfate 28%, polyvinyl sulfate and heparin 66%) in a concentration-independent fashion. Increased concentrations of nonesterified fatty acids markedly interfere with the dextran sulfate and polyvinyl sulfate assay, but do not much affect results with the heparin reagent.

scholarly journals Very-low-density-lipoprotein secretion by isolated hepatocytes of fat-fed rats

1981 ◽  
Vol 198 (2) ◽  
pp. 373-377 ◽  
Author(s):  
A D Kalopissis ◽  
S Griglio ◽  
M I Malewiak ◽  
R Rozen ◽  
X L Liepvre
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Isolated Hepatocytes ◽  
Low Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Lipoprotein Secretion ◽  
Fat Feeding

The very-low-density-lipoprotein secretion rate of isolated hepatocytes obtained from rats fed a high-fat diet was half that of cells from control animals. In fat-fed rats, the initial cellular uptake of [l-14C]oleate in vitro was decreased by 25%, its esterification to triacylglycerols and phospholipids by 50% and its incorporation into very-low-density-lipoprotein triacylglycerols by 70%. Exogenous oleate was not the main precursor of very-low-density lipoproteins in these animals. Lipogenesis, a minor source of very-low-density lipoproteins with the control diet in our experimental conditions, was inhibited by 84% after fat-feeding. A short-term inhibition of lipogenesis in vitro did not result in a decrease in very-low-density-lipoprotein secretion rate. The results suggest that fat-feeding decreased availability of exogenous as well as endogenous fatty acids for synthesis of very-low-density lipoproteins.

The therapeutic effect of some drugs and vegetable juices on the lipid profiles in male rabbits induced atherosclerosis.

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
Sawsan Taha Ahmed al-Haddad ◽  
Zaid Mohammed Mubarak Almahdawi ◽  
Munife S. Ahmed Al-janabi
Keyword(s):  
Green Tea ◽  
Density Lipoprotein ◽  
Lemon Juice ◽  
Low Density Lipoproteins ◽  
High Density ◽  
High Density Lipoproteins ◽  
Control Group ◽  
Low Density ◽  
Very Low Density Lipoproteins ◽  
Group 5

This study was designed to test the therapeutic efficacy of some hypotensive drugs and vegetable drinks on some biochemical indicators in male rabbits, where atherosclerosis was developed using 1% cholesterol with food. This study was conducted in June until the end of July 2017 in the Pharmacology Department/ General Company for Pharmaceutical Industry in Samarra. In the study, 50 local rabbits were randomly distributed by 10 groups each containing 5 animals. The first group considered as the control group. The second group is the control group treated with 1% cholesterol with the food, the third group treated with cholesterol (1% and captopril 0.71 mg), group 4 (cholesterol 1% with atenolol 0.71 mg / kg), group 5 (cholesterol 1%, amlodipine 0.07 mg / kg) , group 6 treated with cholesterol 1% and aldomet (0.57 mg / kg), group 7 (cholesterol 1% and furosemide at 3.5 mg / kg), group 8 (cholesterol 1% with garlic syrup 2 ml), group 9 treatment cholesterol 1% and lemon juice), and group 10 Treatment with (1% cholesterol and green tea syrup 2 ml). The results of the study showed a significant increase (P≤0.01)) at the level of each of cholesterol triple and triglycerides, proteins and low density lipoproteins, very low density lipoproteins, also led to obtain a significant decrease in the level of high-density lipoproteins (HDL) in the treatment group with cholesterol 1% compared to control group. At the time of the treatment of anti- pressure drugs: Captopril, Atenolol, Amlodipine ,Aldomet, and Furosmide , there were no significant differences in the cholesterol level of all pharmacological groups. Moral differences were not found in LDL-C and there was a significant decrease (P≤0.01) of the level of triglycerides, proteins and very low density lipoproteins, and there was a significant increase in the level of high-density lipoproteins HDL-C, while treatment with plant juices, there was a significant decrease (P≤0.01) in the level of total cholesterol and triglycerides and LDL, and VLDL, high-density lipoprotein (HDL-C) increased when treated with garlic, lemon and green tea. We conclude pressure drugs of any kind can cure atherosclerosis or prevent high fat, unlike its counterparts OF plants, which have shown a significant effect on controlling lipid profile and reducing their effects and future risks on the heart.

scholarly journals The effects of monensin on secretion of very-low-density lipoprotein and metabolism of asialofetuin by cultured rat hepatocytes

1985 ◽  
Vol 227 (2) ◽  
pp. 529-536 ◽  
Author(s):  
A C Rustan ◽  
J ∅ Nossen ◽  
T Berg ◽  
C A Drevon
Keyword(s):  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Rat Hepatocytes ◽  
Low Density Lipoproteins ◽  
Very Low Density Lipoprotein ◽  
Low Density ◽  
Dependent Manner ◽  
Very Low Density Lipoproteins ◽  
Low Concentrations ◽  
Maximum Inhibition

Primary cultures of rat hepatocytes were used to study secretion of very-low-density lipoproteins and metabolism of asialofetuin. The ionophore monensin inhibited both secretion of very-low-density lipoproteins and binding and degradation of asialofetuin in a concentration-dependent manner. Secretion as well as receptor binding were markedly decreased after 15 min treatment with monensin. The inhibitory effect of the ionophore was fully reversible, and no effect on protein synthesis was observed at concentrations up to 50 microM. The secretion of apoproteins (B-small, B-large and E) and that of albumin were inhibited to the same extent as was triacylglycerol secretion. Secretion of very-low-density lipoproteins was more sensitive to low concentrations of monensin than was the metabolism of asialofetuin. Maximum inhibition of very-low-density-lipoprotein secretion was obtained at 5-10 microM-monensin, whereas 25 microM was required to obtain maximum inhibition of binding and degradation of asialofetuin. The number of surface receptors for asialofetuin decreased to about half when the cells were exposed to 25 microM-monensin. It is possible that monensin inhibits endo- and exo-cytosis via a similar mechanism, e.g. by disturbing proton gradients. Since secretion of very-low-density lipoproteins was more sensitive to low concentrations of monensin, it is likely that monensin independently inhibits endocytic and secretory functions in cultured hepatocytes.

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