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B Angelin

Publications and source records attributed to B Angelin.

At least 91 records · Page 5Linked to original sources
PubMed1995

Growth hormone treatment does not alter biliary lipid metabolism in healthy adult men.

GH is important for the hepatic low density lipoprotein (LDL) receptor induction that occurs after estrogen treatment. GH treatment increases liver LDL receptors and lowers plasma LDL cholesterol in man. Estrogen treatment enhances biliary secretion of cholesterol, resulting in supersaturation of bile and an increased risk of gallstone formation. The present study was undertaken to investigate whether GH treatment also influences biliary lipid metabolism in humans. Twelve healthy male volunteers (mean age, 31 +/- 1 yr) were studied before and during the third week of treatment with recombinant human GH (0.1 IU/kg.day). Plasma lipids, bile acid kinetics, and biliary lipid composition were monitored. Plasma total and LDL cholesterol levels were reduced by 10% in response to therapy. However, no significant changes were observed in the biliary lipid composition or cholesterol saturation of gallbladder bile. Furthermore, there were no changes in chenodeoxycholic acid or cholic acid kinetics. The reduction of plasma LDL cholesterol in response to GH treatment in healthy adult men is not associated with detectable changes in biliary lipid metabolism. Thus, in contrast to estrogen, GH therapy of adults probably does not result in an increased risk of cholesterol gallstone development.

Adult↗
PubMed1994

Lack of association between apolipoprotein E allele epsilon 4 and sporadic Alzheimer's disease.

Apolipoprotein E (apoE) is a protein involved in the transport of lipids and a component of Alzheimer's disease (AD) plaques. There are three common alleles of the apoE gene, designated epsilon 2, epsilon 3 and epsilon 4. An association between familial and sporadic AD and the epsilon 4 allele was recently reported. We have investigated Swedish Alzheimer patients and controls. The epsilon 4 allele frequency in familial and sporadic cases and in controls was 47, 22 and 18%, respectively. There was no significant difference between sporadic AD and controls but in familial cases the increased epsilon 4 allele frequency previously reported was confirmed.

Aged↗
PubMed1994

Lipid metabolism.

Explore the source record for details and available documents.

Cholesterol↗
PubMed1994

Growth hormone and hepatic lipoprotein metabolism.

Growth hormone (GH) has significant effects on hepatic lipoprotein metabolism, stimulating triglyceride biosynthesis, secretion of VLDL, apolipoprotein (apo)E, and the editing of apoB while simultaneously increasing the expression of LDL receptors. Clinical observations support the concept that GH may have a protective role in the prevention of atherosclerosis, and treatment with GH could thus be beneficial in states of GH deficiency.

Animals↗
PubMed1994

Effects of selective LDL-apheresis and pravastatin therapy on platelet function in familial hypercholesterolaemia.

Platelet function was studied in 10 patients with familial hypercholesterolaemia, following lipid-lowering treatment with selective LDL-apheresis and with the HMG-CoA reductase inhibitor pravastatin. Platelet function was assessed before, and 2, 5 and 14 days after LDL-apheresis, and before and after 4 weeks of pravastatin therapy. Both treatments significantly reduced total- and LDL-cholesterol, whereas LDL-apheresis also reduced VLDL-cholesterol. Lp(a)-levels were reduced by LDL-apheresis and elevated by pravastatin treatment. Pravastatin therapy significantly enhanced platelet aggregability in vivo, as measured by ex vivo filtragometry. Plasma serotonin levels also increased. Other markers of in vivo activation of platelets, i.e. beta-thromboglobulin in plasma and urine, and 11-dehydro-thromboxane B2 in urine were unaltered. Adenosine diphosphate-induced platelet aggregation in vitro remained unchanged during pravastatin therapy, and the platelet volume distribution was not affected. LDL-apheresis reduced the mean platelet volume, as well as the percentage of large platelets, whereas the percentage of small platelets increased. Other measures of platelet function in vivo or in vitro were, however, unaltered following LDL-apheresis. Thus, pravastatin therapy enhances certain aspects of platelet aggregability in vivo, whereas a single treatment with selective LDL-apheresis does not consistently affect platelet aggregability during resting conditions. These results do not support the concept that reduction of LDL-cholesterol improves platelet function in hypercholesterolaemic patients, at least not in the short-term. However, the reduction of platelet volume after LDL-apheresis may be beneficial for patients receiving this therapy regularly.

Adult↗
PubMed1994

Apparent selective bile acid malabsorption as a consequence of ileal exclusion: effects on bile acid, cholesterol, and lipoprotein metabolism.

A new model has been developed to characterise the effect of a standardised ileal exclusion on bile acid, cholesterol, and lipoprotein metabolism in humans. Twelve patients treated by colectomy and ileostomy for ulcerative colitis were studied on two occasions: firstly with a conventional ileostomy and then three months afterwards with an ileal pouch operation with an ileoanal anastomosis and a protective loop ileostomy, excluding on average 95 cm of the distal ileum. The ileostomy contents were collected during 96 hours and the excretion of bile acids and cholesterol was determined using gas chromatography-mass spectrometry. Fasting blood and duodenal bile samples were collected on two consecutive days. After the exclusion of the distal ileum, both cholic and chenodeoxycholic acid excretion in the ileostomy effluent increased four to five times without any change in cholesterol excretion. Serum concentrations of lathosterol (a marker of cholesterol biosynthesis) and 7 alpha-hydroxycholesterol (a marker for bile acid biosynthesis) were increased several fold. Plasma concentrations of total VLDL triglycerides were also increased whereas the concentrations of total and LDL cholesterol, and apolipoprotein B were decreased. There were no changes in biliary lipid composition or cholesterol saturation of bile. The results show that the exclusion of about 95 cm of distal ileum causes malabsorption of bile acids but apparently not of cholesterol. The bile acid malabsorption leads to increased synthesis of both bile acids and cholesterol in the liver. It is suggested that bile acids can regulate cholesterol synthesis by a mechanism independent of the effect of bile acids on cholesterol absorption. The enhanced demand for cholesterol also leads to a decrease in plasma LDL cholesterol and apolipoprotein B concentrations. The malabsorption of bile acids did not affect biliary lipid composition or cholesterol saturations of VLDL triglycerides.

Adult↗
PubMed1994

Effects of ursodeoxycholic acid on plasma lipids.

Interference with the enterohepatic circulation leads to changes in plasma lipoprotein metabolism. Thus, increased bile acid synthesis (such as after cholestyramine therapy or biliary diversion) stimulates hepatic triglyceride production and increases the number of low density lipoprotein (LDL) receptors in the liver. However, treatment with chenodeoxycholic acid reduces triglyceride production and appears to reduce LDL catabolism. Ursodeoxycholic acid therapy, which has minor effects on bile acid synthesis, results in relatively minor changes in lipoprotein metabolism. A tendency for lowered LDL cholesterol levels may be related to the fact that ursodeoxycholic acid interferes with the enterohepatic circulation of the normal bile acids, particularly when administered at a high dosage.

Cholesterol, LDL↗
PubMed1994

Time-resolved fluorometry in the genetic diagnosis of familial defective apolipoprotein B-100.

A novel technique for screening point mutations has been developed for diagnosis of familial defective apolipoprotein (apo) B-100 (FDB). In FDB, an amino acid exchange occurs at position 3500 in apoB-100 due to a point mutation. Polymerase chain reaction (PCR) was performed on the appropriate region of the apoB gene, and the PCR products were hybridized in solution with europium-labeled oligonucleotides, complementary to either the wildtype or the mutant genome. The presence or absence of the apoB-3500 mutation was monitored by time-resolved fluorescence of the europium chelate. The method allows a larger number of samples to be processed simultaneously, and the detection system displays a high level of sensitivity without the hazards connected to the use of radioactivity. When 127 Swedish patients, clinically diagnosed as suffering from heterozygous familial hypercholesterolemia, were screened for the presence of the apoB-3500 mutation, two patients, unrelated to each other, were found to be heterozygotes. These patients are the first reported cases of FDB from Sweden, and the frequency rate observed among hypercholesterolemic patients, 1.6%, is in accordance with the figures reported for several other patient population in Europe and the United States.

Adult↗
PubMed1994

Treatment of IgA nephropathy with omega-3-polyunsaturated fatty acids: a prospective, double-blind, randomized study.

In several studies diets supplemented with fish oil containing a high proportion of omega-3-polyunsaturated fatty acids (w-3-PUFA) have been shown to produce beneficial effects, such as a reduction in blood pressure, lipid levels and inflammation, all of which may affect the course of IgA nephropathy. However, the results of hitherto published studies concerning IgA nephropathy have been inconclusive. We therefore carried out a prospective, randomized, placebo-controlled six-month study with a higher daily dose of w-3-PUFA than used in previous studies. Thirty-two adult patients with biopsy-proven IgA nephropathy and proteinuria completed the study: 15 were assigned to a fish-oil product with a high percentage of w-3-PUFA (K 85, with 55% eicosapentenoic and 30% docosahexenoic acid) and 17 to corn oil, 6g daily of either oil. At the start, no significant differences were found between the two groups (K85: 3 females/12 males, mean age 39 years (range 22-64), corn oil: 4 females/13 males, age 42 years (range 26-68). By six months, supplements of K85 resulted in a slight but significant reduction in glomerular filtration rate (GFR) compared to the start: 51Cr-EDTA: 63 +/- 22 to 59 +/- 21 ml/min/1.73 m2 (p < 0.05), creatinine clearance: 91 +/- 31 to 79 +/- 25 ml/min (p < 0.01), s-creatinine: 131 +/- 39 to 139 +/- 39 mumol/l, whereas no change in GFR was observed in the corn oil group. The urinary total protein and red blood cell excretions were not affected in any of the groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1993

Loss of resistance to dietary cholesterol in the rat after hypophysectomy: importance of the presence of growth hormone for hepatic low density lipoprotein-receptor expression.

This investigation was undertaken to determine the role of pituitary function and, in particular, the possible influence of growth hormone (GH) on hepatic low density lipoprotein (LDL)-receptor expression in response to dietary cholesterol. Feeding normal rats with 2% cholesterol for 5 or 6 days did not alter LDL-receptor numbers, LDL-receptor mRNA levels, or plasma cholesterol, although hepatic cholesterol increased 5-fold. When hypophysectomized rats received the same diet, the LDL-receptor number and its mRNA levels were reduced by 75%, plasma cholesterol increased 6-fold, and hepatic cholesterol increased 12-fold. Stepwise hormonal substitution of cholesterol-fed, hypophysectomized rats revealed that substitution with GH was important to restore hepatic LDL-receptor number and mRNA levels. The presence of GH was also important to reduce the hypercholesterolemia in cholesterol-fed hypophysectomized rats. We conclude that the presence of GH is important for hepatic LDL-receptor expression, both at the protein and the mRNA level. The resistance to suppression of rat hepatic LDL receptors by dietary cholesterol depends, at least in part, on the presence of GH.

Animals↗
PubMed1993

Pravastatin and gemfibrozil alone and in combination for the treatment of hypercholesterolemia.

PURPOSE: To compare the efficacy and safety of pravastatin, gemfibrozil, combined therapy, and placebo in the treatment of hypercholesterolemia. PATIENTS AND METHODS: At 5 centers in Sweden and 2 in Finland, 290 ambulatory patients were randomized to active treatment or placebo for 12 weeks following a single-blind placebo lead-in period. The study was double-blind and placebo-controlled. Patients has plasma total cholesterol levels of at least 6.0 mmol/L or in the 90th percentile by age and sex and triglycerides less than 4.0 mmol/L. Concentrations of lipids, lipoproteins, and apolipoproteins were measured, and clinical laboratory tests included liver function and creatine kinase determinations. RESULTS: Pravastatin reduced total cholesterol (26.3% versus 15.2%, p < or = 0.01), low-density lipoprotein cholesterol (LDL-C) (33.5% versus 16.8%, p < or = 0.01), and apolipoprotein B (28.8% versus 15.3%, p < or = 0.01) more than gemfibrozil. Gemfibrozil reduced very-low-density lipoprotein cholesterol (VLDL-C) (49.1% versus 21.9%, p < or = 0.01) and triglycerides (42.2% versus 14.2%, p < or = 0.01) and increased high-density lipoprotein cholesterol (HDL-C) (15.2% versus 5.9%, p < or = 0.01) more than pravastatin. Pravastatin and gemfibrozil increased apolipoprotein A-I comparably (3.3% versus 5.0%, p = NS). The combination significantly (p < or = 0.01) reduced total cholesterol (29.0%), LDL-C (37.1%), VLDL-C (49.4%), and apolipoprotein B (31.6%), and increased HDL-C (16.8%). The combination reduced the total cholesterol/HDL-C (39.3%) and LDL-C/HDL-C (45.8%) ratios significantly (p < 0.01). Adverse events and clinical laboratory abnormalities were generally mild and transient in all groups, although creatine kinase tended to be higher with combination therapy. Study drugs were withdrawn from two patients with asymptomatic creatine kinase elevations. Severe myopathy was not observed; however, the presence of subclinical musculoskeletal effects cannot be excluded. CONCLUSIONS: Co-administration of pravastatin and gemfibrozil combined the specific effects of the two drugs on lipoprotein concentrations and ratios. The incidence of side effects was low; severe myopathy did not occur. The combination may be useful in selected cases of combined hyperlipidemia; however, since myopathy at a low incidence or after long-term therapy cannot be excluded, the routine use of combination therapy is not advisable.

Adult↗
PubMed1993

Non-steady-state kinetics of low density lipoproteins in man: studies after plasma exchange in healthy subjects and patients with familial hypercholesterolaemia.

Five patients with heterozygous familial hypercholesterolaemia (FH), one patient with non-familial hypercholesterolaemia, and four healthy normals were treated with plasma exchange (PE). In order to achieve a non-steady-state situation with low plasma cholesterol levels, PE was performed twice in each subject at an interval of 1-3 days. At each time, 1500 ml of plasma were removed and replaced with colloids and albumin. Lipoprotein analyses were performed daily in all subjects for a period of 14 days following PE. Kinetic calculation of LDL cholesterol data using a two-compartment open model was performed, and rate constants, synthetic rate and apparent clearance of LDL were determined. A lower clearance and a tendency towards a higher synthesis of LDL were observed in the FH patients. In four of the subjects, LDL kinetics was also studied with the conventional 125I-LDL turnover technique. The synthetic rates of LDL were compared using data derived from PE and 125I-LDL kinetics. The two techniques showed a good correlation (r = +0.93) although synthetic rates in general were higher when calculated from the 125I-LDL procedure (3.98 vs. 2.64 mmol d-1 for LDL cholesterol synthesis). The results indicate that non-steady-state kinetics of LDL, as measured using the PE technique, is a useful method for analysis of LDL metabolism.

Adult↗
PubMed1993

Apolipoprotein E phenotypes in familial hypercholesterolaemia: importance for expression of disease and response to therapy.

To study the possible importance of variation at the apolipoprotein (apo) E gene locus for the clinical expression of heterozygous familial hypercholesterolaemia (FH), we determined apo E phenotype and serum lipoprotein pattern in 120 patients with FH. The allele frequency of the patients studies were: epsilon 2 0.033, epsilon 3 0.733, and epsilon 4 0.233. There was no influence of apo E phenotype on the serum concentrations of total. VLDL, LDL or HDL cholesterol, triglycerides, or of apo AI, B or (a). Serum concentrations of apo E were significantly higher in patients with the apo E 3/3 phenotype compared to those with apo E 4/3 or 4/4, and the highest concentrations were found in patients carrying the epsilon 2-allele. The cholesterol-lowering response to therapy with cholestyramine or pravastatin was not related to apo E phenotype. It is concluded that variation at the apo E gene locus is not of major importance for the expression of heterozygous FH.

Apolipoproteins E↗
PubMed1993

Serum 7 alpha-hydroxy-4-cholesten-3-one concentrations in the evaluation of bile acid malabsorption in patients with diarrhoea: correlation to SeHCAT test.

The synthesis of bile acids is regulated by a homeostatic mechanism in which bile acids returning to the liver from the intestine inhibit their own synthesis. Serum concentrations of the bile acid intermediate 7 alpha-hydroxy-4-cholesten-3-one reflect the rate of bile acid synthesis whereas bile acid malabsorption can be determined by the SeHCAT test. This study was done to evaluate the correlation between the two tests in humans. Twenty eight patients with chronic diarrhoea were included in the study. Fasting serum was collected for the determination of 7 alpha-hydroxy-4-cholesten-3-one, and on the same day the gamma emitting bile acid analogue SeHCAT was given orally and its fractional catabolic rate assessed by repeated external counting over the upper abdomen during the next seven days. There was a highly significant positive correlation between the two tests (Rs = 0.80, p < 0.001). The results show a close relation between intestinal loss and hepatic synthesis of bile acids and imply that analysis of 7 alpha-hydroxy-4-cholesten-3-one in serum should now be evaluated as a possible convenient method for assessing bile acid malabsorption in patients with diarrhoea.

Adult↗