scholarly journals Clearance from plasma of lymph chylomicrons and chylomicron remnants labelled with 125I-tyramine-cellobiose

1992 ◽  
Vol 286 (3) ◽  
pp. 937-943 ◽  
Author(s):  
H L Ly ◽  
B C Mortimer ◽  
E Baker ◽  
T G Redgrave
Keyword(s):  
High Density Lipoprotein ◽  
Lipoprotein Lipase ◽  
Bovine Milk ◽  
Density Lipoprotein ◽  
High Density ◽  
Low Density ◽  
Apolipoprotein B48 ◽  
Chylomicron Remnants

The aims of the present study were to evaluate the metabolism of chylomicrons (CM) and of CM remnants after labelling with radioactive iodine and converting the iodinated CM into remnants in vitro. Lymph CM were radiolabelled with 125I or sham-labelled with 127I by either the ICl procedure or the tyramine-cellobiose (TC) procedure, then injected into rats. The clearance from plasma of the iodinated CM was compared with control non-iodinated lipid-labelled CM. After iodination with ICl, the plasma removal of endogenously labelled CM was significantly different from non-iodinated CM, with increased uptake of CM triacylglycerols by the liver. In contrast, the clearances from plasma and the uptake by organs of radiolabelled lipids of CM iodinated by the TC method (TC-CM) were similar to control CM. About 40% of the label from 125I-TC-CM was insoluble in 50% propan-2-ol, indicating association with CM apolipoprotein B48. Only about 8% of label was lipid soluble, mostly in phosphatidylethanolamine. Radioactivity from 125I-TC-CM injected intravenously in rats was cleared rapidly and by 30 min only 20% remained in plasma, whereas 48% was recovered in the liver. After fractionation of the plasma by density-gradient ultracentrifugation, most label remained associated with d (relative density) less than 1.006 lipoproteins. In intact rats label was also found associated with the low-density and high-density lipoprotein fractions of plasma. When the liver was excluded from circulation, the recovery of label in low-density- and high-density-lipoprotein fractions was greatly decreased. CM remnants were prepared in vivo by injecting 125I-TC-CM into functionally hepatectomized donors and compared with remnants prepared in vitro by incubation with purified bovine milk lipoprotein lipase. Although remnants prepared in vitro cleared from plasma slower than remnants prepared in vivo, the size, lipid composition and apolipoprotein profile on gradient PAGE of the remnants were similar. We conclude that labelling of CM by the TC method avoided the ‘artefactual’ changes in metabolism seen after labelling by the ICl procedure. CM remnants when prepared in vitro using lipoprotein lipase were found to be similar to those prepared in vivo after injection into functionally hepatectomized rats.

scholarly journals The effect in vitro of high-density lipoprotein on hydrolysis of triacylglycerol by lipoprotein lipase

1981 ◽  
Vol 200 (2) ◽  
pp. 453-456 ◽  
Author(s):  
M P Rogers ◽  
I Hutchinson
Keyword(s):  
Adipose Tissue ◽  
High Density Lipoprotein ◽  
Lipoprotein Lipase ◽  
Bovine Milk ◽  
Density Lipoprotein ◽  
High Density ◽  
Rat Adipose Tissue ◽  
Adipose Tissue Lipoprotein Lipase ◽  
Hydrolysis Of

In an incubation system in vitro with fully activated Intralipid as substrate, rat high-density lipoprotein inhibits the hydrolysis of triacylglycerol by lipoprotein lipase from rat adipose tissue, but does not inhibit hydrolysis by the enzyme from bovine milk. The pattern of inhibition suggests that substrate and high-density lipoprotein may compete for association with rat adipose-tissue lipoprotein lipase.

Rapid transformation of [3H]cholesteryl ester m rat high-density lipoprotein: in vivo and in vitro studies

Steroids ◽  
1990 ◽  
Vol 55 (7) ◽  
pp. 308-313
Author(s):  
I.J. Goldberg ◽  
R.S. Rosenfeld ◽  
I. Paul ◽  
L.K. Miller ◽  
M.L. Tiell
Keyword(s):  
High Density Lipoprotein ◽  
Cholesteryl Ester ◽  
Density Lipoprotein ◽  
High Density ◽  
In Vitro Studies ◽  
Rapid Transformation

scholarly journals Potensi Hipolipidemik Yogurt dari Isolat Protein Biji Kecipir (Psophocarpus tetragonolobus) pada Tikus Hiperkolesterol dengan Perlakuan Jumlah Pakan

2017 ◽  
Vol 37 (1) ◽  
pp. 1
Author(s):  
Agus Slamet ◽  
Bayu Kanetro
Keyword(s):  
High Density Lipoprotein ◽  
Low Density Lipoprotein ◽  
Density Lipoprotein ◽  
Protein Isolate ◽  
High Density ◽  
Winged Bean ◽  
Low Density ◽  
Sprague Dawley ◽  
High Concentration

Protein content of winged bean is almost the same as soybean, but the beany flavor is more poweful than soybean. Therefore the protein of winged bean was isolated prior to use as raw material of yogurt. This research was aimed to determine the potency of  hypocholestrolemic activity of yogurt protein isolate of winged  bean through in vivo bioassay by using Sprague Dawley male rats. The treatments of the research were yogurt feed treatment with concentration of yogurt 0 (standard feed without yogurt as a control), 2, and 4 g yogurt/day as low and high concentration treatment respectively for 4th weeks after hypercholesterol feed  treatment for 1 week. The blood lipid profile of rats, including triglyceride, cholesterol total, High Density Lipoprotein (HDL), Low  Density Lipoprotein (LDL) cholesterol were analysed on the 2nd  and 4th weeks for the yogurt feed treatment while for before  yogurt feed treatment, the evaluation were based on the  adaptation phase and the 1st week for hypercholesterol phase.  The result of this research showed that the blood triglyceride,  cholesterol total, LDL increased, and the blood HDL decreased in hypercholesterol phase before yogurt feed treatment. The potency of hypocholestrolemic of yogurt from protein isolate of winged  bean was shown by the decreasing of blood triglyceride,  cholesterol total, LDL and increasing the HDL cholesterol after the yogurt feed treatment with low and high concentration. That  indicated that yogurt that was made of protein isolate of winged  bean could reduced cholesterol. ABSTRAKBiji kecipir memiliki kadar protein yang hampir sama dengan  kedelai, namun bau langunya lebih tajam daripada kedelai,  sehingga perlu diisolasi proteinnya sebelum digunakan sebagai  bahan baku yogurt. Tujuan penelitian ini adalah menentukan  potensi hipokolesterolemik yogurt isolat proteun biji kecipir  melalui uji biologis in vivo menggunakan tikus jantan Sprague Dawley. Perlakuan penelitian ini adalah perlakuan pakan yogurt  dengan konsentrasi 0 (pakan standar tanpa penambahan yogurt sebagai kontrol), 2, dan 4 g yogurt/hari berturut-turut sebagai  perlakuan konsentrasi rendah dan tinggi selama 4 minggu  perlakuan pakan yogurt sesudah pemberian pakan hiperkolesterol selama 1 minggu. Profil lipida darah tikus meliputi kadar trigliserida, total kolesterol, kolesterol High Density  Lipoprotein (HDL), dan Low Density Lipoprotein (LDL) dianalisis  pada minggu ke 2 dan 4 minggu selama perlakuan pakan yogurt  dan sebelum perlakuan pakan yogurt yaitu pada fase pemeliharaan adaptasi dan 1 minggu pada fase pemeliharan  hiperkolesterol. Hasil penelitian ini menunjukkan bahwa  trigliserida, total kolesterol, dan kolesterol LDL meningkat dan kolesterol HDL menurun selama fase pemberian pakan  hiperkolesterol sebelum perlakuan pakan yogurt. Potensi  hipokolesterol yogurt isolat protein biji kecipir ditunjukkan dengan penurunan trigliserida, total kolesterol, dan kolesterol LDL, serta peningkatan kolesterol HDL sesudah perlakuan pakan yogurt dengan konsentrasi rendah maupun tinggi. Hal tersebut mengindikasikan bahwa yogurt isolat protein biji kecipir mampu menurunkan kolesterol.

Synthesis of recombinant high density lipoprotein with apolipoprotein A-I and apolipoprotein A-V

2011 ◽  
Vol 392 (5) ◽  
Author(s):  
Xinbo Zhang ◽  
Baosheng Chen
Keyword(s):  
High Density Lipoprotein ◽  
Low Density Lipoprotein ◽  
Atherosclerotic Lesion ◽  
Density Lipoprotein ◽  
High Density ◽  
Over Expression ◽  
Apolipoprotein A ◽  
Atherosclerotic Lesion Development

Abstract It has been shown that apolipoprotein A-V (apoA-V) over-expression significantly lowers plasma triglyceride levels and decreases atherosclerotic lesion development. To assess the feasibility of recombinant high density lipoprotein (rHDL) reconstituted with apoA-V and apolipoprotein A-I (apoA-I) as a therapeutic agent for hyperlipidemic disorder and atherosclerosis, a series of rHDL were synthesized in vitro with various mass ratios of recombinant apoA-I and apoA-V. It is interesting to find that apoA-V of rHDL had no effect on lipoprotein lipase (LPL) activation in vitro and very low density lipoprotein (VLDL) clearance in HepG2 cells and in vivo. By contrast, LPL activation and VLDL clearance were inhibited by the addition of apoA-V to rHDL. Furthermore, the apoA-V of rHDL could not redistribute from rHDL to VLDL after incubation at 37°C for 30 min. These findings suggest that an increase of apoA-V in rHDL could not play a role in VLDL clearance in vitro and in vivo, which could, at least in part, attribute to the lost redistribution of apoA-V from rHDL to VLDL and LPL binding ability of apoA-V in rHDL. The therapeutic application of rHDL reconstituted with apoA-V and apoA-I might need the construction of rHDL from which apoA-V could freely redistribute to VLDL.

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