To reveal the presence of atherogenic potential in the blood serum obtained from patients with angiographically assessed coronary atherosclerosis we used primary cultures of subendothelial cells isolated by collagenase from unaffected human aortic intima. Earlier, we have demonstrated that such cultures are made up mostly of typical and modified smooth ...

With the advent of nocturnal intragastric feeding which protects against acute metabolic complications and promotes growth, patients with glycogen storage disease type I are attracting less attention. However, several biochemical alterations persist and suggest that the long-term risk of atherosclerotic heart disease remains high. Persisting hypertriglyceridemia and hypercholesterolemia were found ...

We studied the precipitation of isolated lipoproteins with heparin and MnCl2. Lipoproteins were isolated from human plasma by preparative ultracentrifugation and their free cholesterol was labeled. Each lipoprotein fraction was then precipitated at various pHs, with or without bovine serum albumin (60 g/L) present. Under no set of conditions was ...

The effects of acitretin (free acid of etretinate) on the serum lipoprotein pattern and on the fat elimination in serum of 8 patients with psoriasis and 4 with palmo-plantar pustulosis were studied. The drug was given for 12 weeks; the average daily dose was 40 mg. Lipoprotein analyses and an ...

It has been well documented that low-density lipoproteins and intermediate-density lipoproteins play a role in the development of atherosclerosis. Data also indicate that high-density lipoproteins (HDLs), have potentially antiatherogenic effects. The individual estrogen and progestogen components of oral contraceptives (OCs) have been shown to affect plasma lipoproteins in both cross-sectional ...

Envenomation by snake venoms would be expected to result in proteolysis of plasma proteins as well as of cellular constituents. Incubation of human serum with crude venom from Cerastes cerastes showed that the plasma lipoproteins were a target of this venom. Fractionation of the crude venom by gel filtration revealed ...

Retinyl ester concentrations in plasma from fasting humans, rabbits and rats are usually negligible. In contrast, plasma from fasting dogs contains appreciable amounts of retinyl esters, associated almost entirely with the low-density lipoproteins. This study was undertaken to gather additional information about the nature and origin of canine retinyl ester-containing ...

The rate of clearance of lipoproteins from plasma appears to play a role in the development of atherogenesis. The liver may account for as much as two thirds of the removal of low-density lipoprotein and one third of the clearance of high-density lipoprotein in certain animal species and humans, mainly ...

The use of anabolic steroids to augment athletic performance is widespread. It is known that these drugs can adversely affect lipoproteins in normal volunteers, leading to increased cholesterol and low density lipoprotein and depressed high density lipoprotein. It has been shown that endurance type exercise can lead to beneficial effects ...

We have previously demonstrated that the fetus with anencephaly is hypercholesterolemic. The plasma levels of total cholesterol and low-density lipoprotein cholesterol are threefold greater than those of normal fetuses. We have provided evidence that elevated low-density lipoprotein cholesterol levels were caused by reduced uptake and metabolism of low-density lipoprotein by ...

Previous analysis of amniotic fluid (AF) noted only the presence of high density lipoprotein (HDL). In this study AF lipoprotein profile was examined using gel filtration column chromatography and Ouchterlony gel diffusion. Unlike previous studies which showed only the presence of HDL, we found significant amounts of low density lipoprotein ...

The major effect of the fibrates on triglycerides is to promote triglyceride-rich lipoprotein catabolism through increased lipoprotein lipase activity. Fibrates also enhance lipolysis of plasma triglycerides by a means different from that of caloric restriction. Their effect on very low-density lipoprotein metabolism also differs from that of nicotinic acid. The ...

The fibric acid derivatives, including fenofibrate, significantly reduce very low-density lipoprotein triglyceride concentrations by stimulating lipoprotein lipase activity, thereby increasing very low-density lipoprotein catabolism. These agents may also reduce the hepatic secretion of nascent very low-density lipoprotein, but this effect is less consistent. Effects on low-density lipoprotein metabolism appear to ...

We have previously shown that cultured rat alveolar macrophages synthesize and secrete lipoprotein lipase into the medium. The purpose of the present experiments is to examine whether cholesterol-enriched lipoproteins from cholesterol-fed animals have any effects on the lipoprotein lipase secretion and the lipid accumulation in macrophages. Macrophages incubated with the ...

Serum lipids and lipoprotein patterns were prospectively analyzed in 33 previously untreated patients with active chronic inflammatory arthritides during different anti-inflammatory and disease-modifying drug regimens. Before treatment the lipoprotein pattern was characterized by low cholesterol concentrations in all lipoprotein fractions and low triglyceride concentrations in the very-low-density lipoprotein fraction as ...

It has been proposed that an endogenously synthesized oxysterol mediates the regulation of cholesterol biosynthesis by low density lipoprotein in cultured mammalian cells. Studies in this report demonstrate that under conditions in which squalene conversion to sterols is blocked either by inhibition of squalene cyclization or lanosterol demethylation, or both, ...

Cynomolgus monkeys (Macaca fascicularis) fed monkey chow (n = 10) had a mean +/- SD post-heparin plasma lipoprotein lipase (LPL) activity level (14.7 +/- 5.5 units/ml) similar to that found in human beings (15.7 +/- 3.9 units/ml). However, the hepatic triglyceride lipase (H-TGL) in these monkeys was extremely low (0.5 ...

We investigated the effects of ethynylestradiol (EE) at low dose (1.2 micrograms/day) injected s.c. for 10 days on lipoprotein lipase (LPL) in fat cells of female rats fed a standard diet (5% lipid, 49.5% glucid, 23.5% protein) as a function of the nutritional state. EE caused a 150% increase in ...

Because lipoproteins containing apolipoprotein A (ApoA-I + ApoA-II) or apolipoprotein B (ApoB) seem to exert opposite effects as risk factors for coronary heart disease, we decided to determine the separability of these two major plasma lipoproteins by procedures originally designed to separate high-density from low- and very-low-density lipoproteins. The presumably ...

I have previously described [Babin (1987) J. Biol. Chem. 262, 4290-4296] the apolipoprotein composition of the major classes of trout plasma lipoproteins. The present work describes the use of an isopycnic density gradient centrifugation procedure and sequential flotation ultracentrifugation to show: (1) the presence of intermediate density lipoproteins (IDL) in ...

Prostaglandin (PG) E1 was demonstrated to stimulate the transfer of phosphatidylcholine and cholesterol esters from human high density lipoproteins (HDL3) to low density lipoproteins (LDL). The enhancement effect of PGE1 on the interlipoprotein lipid transfer was seen at low PG concentrations under conditions of spontaneous exchange as well as in ...

Limited information is available regarding the relationship between physical activity and blood lipids in black populations. To assess the association, the authors measured high-density lipoprotein cholesterol (HDL-C) and subfractions (HDL(2)-C, HDL(3)-C), physical activity (Harvard Alumni Survey), height, weight, cigarette, alcohol, and oral contraceptive use (questionnaire) in a sample of 173 ...

Feline serum lipoproteins were fractionated into four distinct classes by density gradient ultracentrifugation and characterized with respect to physical and chemical properties. The distribution of serum lipids, lipoproteins and apolipoproteins was quite unlike that in man, the cat having five times as much high density lipoproteins (HDL) as low density ...

The capacity of lipoprotein fractions to provide cholesterol necessary for human lymphocyte proliferation was examined. When endogenous synthesis of cholesterol was blocked, proliferation of mitogen-stimulated normal human lymphocytes was markedly inhibited unless an exogenous source of sterol was supplied. All lipoprotein fractions with the exception of high density lipoprotein subclass ...

The effects of serum lipids and lipoproteins of 2 mg cyproterone acetate (CPA) given alone and in combination with 35 or 50 micrograms ethinyl estradiol (EE) were studied in 21 oophorectomized women in a study with a cross-over design. CPA in this low oral dose was rather inert in its ...

Trapidil, a triazolopyrimidine, and its derivatives are coronary vasodilating drugs. Trapidil reduces the serum level of low density lipoprotein- and very low density lipoprotein-cholesterol and increases the serum level of high density lipoprotein-cholesterol in hyperlipemic patients. The present study demonstrates that trapidil and five different trapidil derivatives inhibit the proliferation ...

Numerous clinical studies have shown that propranolol administration causes hypertriglyceridemia and a decrease in high-density lipoprotein in man. Although these findings have been attributed to diminution of triacylglycerol-rich lipoprotein catabolism by lipoprotein lipase, biochemical studies of the effects of propranolol on lipoprotein lipase activity in vitro have not been previously ...

To study exogenous fat metabolism, we used the vitamin A-fat loading test, which specifically labels intestinally derived lipoproteins with retinyl palmitate (RP). Postprandial RP concentrations were followed in total plasma, and chylomicron (Sf greater than 1,000) and nonchylomicron (Sf less than 1,000) fractions. In normal subjects postprandial lipoproteins were present ...

We examined lipoproteins and apolipoproteins in serum of a Tangier-disease patient. We used three different techniques of micro-scale two-dimensional electrophoresis: (a) no denaturants; (b) with sodium dodecyl sulfate (SDS) used only in the slab gel electrophoresis; (c) and with urea and a detergent used in isoelectric focusing and with SDS ...

The effect of low density lipoproteins on esterification of cholesterol was studied in lymphocytes from patients with familial hypercholesterolaemia; results were compared with those obtained using cells from normal individuals. Freshly isolated lymphocytes were maintained in lipoprotein-deficient medium for 48 h and the rate of formation of [3H] cholesteryl oleate ...

Rhesus monkeys were fed corn or coconut oil-based diets for 3-6 mo to determine effects on the composition of all lipoprotein classes and on the metabolism of high density lipoproteins (HDL). Major findings included the following. Coconut oil feeding increased concentrations of all classes of plasma lipoproteins without altering lipoprotein ...

Eight infants presented with a malabsorption syndrome, normal fasting triglycerides, hypocholesterolemia (64.3 +/- 10.0 mg/dl), and deficiency of vitamins A and E. Plasma low-density lipoprotein, apolipoprotein B, and apolipoprotein A-I were decreased. After a fatty meal, plasma triglycerides did not increase and chylomicrons could not be identified. Lipoprotein composition was ...

Fifty-eight follicular fluids (FF) were obtained from 18 women undergoing in vitro fertilization (IVF). Follicular development was induced by human menopausal gonadotropin (hMG) and follicular aspiration was performed 36 hr after an ovulatory dose of human chorionic gonadotropin (hCG). Two stages of oocyte-corona-cumulus complexes (OCCCs) morphological maturation was identified in ...

To evaluate changes in arterial wall uptake of an atherogenic lipoprotein in early atherogenesis the uptake of labelled low density lipoprotein was measured in four segments of aorta in Cynomolgus monkeys with diet induced fatty streaks. The influx rate of low density lipoprotein was estimated from a simple kinetic model. ...

The effects of alpha 1-adrenergic receptor inhibition with doxazosin, and beta-blockade with propranolol on tissue lipoprotein lipases and plasma lipids were studied in rats. In rats fed a normal lab chow, doxazosin increased heart lipoprotein lipase activity (+14%), while propranolol had the opposite effect (-20%). These effects were not statistically ...

1. Plasma lipids and lipoproteins of free-ranging howling monkeys from Costa Rica (Alouatta palliata), aged 5 months to 23 years, were characterized. 2. High density lipoproteins were lipid-rich, similar to HDL2 of human plasma. 3. Fatty acid compositions of major lipid classes of very low, low and high density lipoproteins ...

Changes in the level of plasma lipids (cholesterol, fatty acids and lipoproteins) were followed in young rats exposed once or repeatedly to hypobaric hypoxia. A single exposure to hypoxia increased the level of LDL lipoproteins but did not influence the concentration of cholesterol and fatty acids in 18-day-old rats. Repeated ...

1. We have recently reported the ability of orally administered l-carnitine to lower plasma triglyceride in the Watanabe Heritable Hyperlipidemic Rabbit (WHHL), an animal model of familial hyperlipoproteinemia. 2. In the present studies we examined the effect of l-carnitine administration upon individual lipoprotein subfractions in this animal model. 3. Carnitine ...

1. Plasma lipoproteins from six thoroughbred horses were separated by density gradient ultracentrifugation. For each sample, lipoprotein bands were visualized by means of a prestained plasma control and characterized by electrophoretic, chemical and morphological analysis. 2. Very low density lipoproteins (VLDL) were isolated at d less than 1.018 g/ml. 3. ...

1. Plasma lipoproteins from six calves at 8, 43 and 118 days old, six heifers and six cows were separated by density gradient ultracentrifugation. For each sample lipoproteins bands were visualized by prestained control and characterized by electrophoretic, chemical and morphological analysis. 2. Two resolved bands were detected in the ...

Density gradient ultracentrifugation has been used to analyse the lavage from the proximal intrapulmonary bronchi of normal human volunteers and of dogs. The secretion from explants of canine trachea and human lobar bronchi has been examined under basal conditions and after stimulation by secretagogues. Mucus from the hypersecretory airways has ...

1. Plasma lipids and lipoproteins were studied in 9 male patients during the immune phase of leptospirosis and 4 months later after recovery. 2. Electrophoretic patterns of plasma lipoproteins were characterized by the absence of alpha- and pre-beta lipoprotein bands and the presence of a single broad beta band. The ...

Lipoprotein biosynthesis in larvae of the tobacco hornworm (Manduca sexta) was investigated. By immunoblotting, it was shown that the apoproteins are present in the fat body, but not in the midgut. Fat body incubated in vitro with [35S]methionine secreted labeled apoproteins. However, when the density of the secreted particle was ...

A strain of pigs bearing three immunogenetically defined lipoprotein-associated markers (allotypes), designated Lpb5, Lpr1, and Lpu1, has marked hypercholesterolemia on a low fat, cholesterol-free diet. Unlike individuals with familial hypercholesterolemia or WHHL rabbits, the affected pigs have normal low density lipoprotein receptor activity. The animals, by 7 months of age, ...

It has been shown previously that the rat hepatoma no. 7288C grown in vivo or in vitro expresses fewer receptors which recognize chylomicron remnants than does normal rat liver, and it was suggested that this may contribute to the deletion of dietary cholesterol-induced regulation of cholesterol synthesis in hepatomas (Barnard, ...

A routine procedure for the ultracentrifugal analysis of human plasma lipoproteins by means of a fixed angle rotor was developed. It was applied as reference method for the evaluation of two widely used procedures of lipoprotein analysis, i.e. measurement of HDL-cholesterol after precipitation of the apolipoprotein B containing lipoproteins with ...

A study on the fractionation of human plasma into various lipoprotein classes was performed by single spin vertical ultracentrifugation. Detailed apolipoprotein (A-I, A-II, B, C-III, and E) and lipid (cholesterol, cholesterol ester, and triacylglycerol) analyses were performed on the fractions obtained by single spin vertical ultracentrifugation. ApoB was located primarily ...

Purification of the oily, nonpolar fraction of high protein barley (Hordeum vulgare L.) flour by high pressure liquid chromatography yielded 10 major components, two (I, II) of which were potent inhibitors of cholesterogenesis in vivo and in vitro. The addition of purified inhibitor I (2.5-20 ppm) to chick diets significantly ...

Apolipoproteins play major roles in regulating lipoprotein synthesis and catabolism. Apolipoprotein AI activates the lecithin cholesterol acyltransferase, apolipoprotein CII and CIII regulate the lipoprotein lipase, and apolipoprotein B-100, B-48, and E control the cholesterol uptake into hepatic and extrahepatic cells. Therefore, investigating the alterations of lipoprotein metabolism in disease states ...

The ultracentrifugal fractionation of human serum after previous incubation with cyclosporin A showed that, in healthy fasting individuals, 8% of cyclosporin A was found in the very low density lipoproteins (VLDL), 31% in the low density lipoproteins (LDL), 46% in the high density lipoproteins (HDL) and 15% in the non-lipoprotein ...