Sigmundur Gudbjarnason

University of Iceland | HI · Science Institute

Angelica archangelica fruits were collected from 64 locations around Iceland and analysed for furanocoumarins by high-performance liquid chromatography. The average furanocoumarin content was found to be 22.5 mg/g, ranging from 14.0 to 31.6 mg/g. Whereas imperatorin was the main compound in all samples, the order of other compounds was highly diver...

The aim of this study was to explore the acetylcholinesterase (AChE) inhibition of several Icelandic medicinal herbs. Ethanolic extracts of Angelica archangelica seeds and the aerial parts of Geranium sylvaticum proved effective, with IC50 values of 2.20 mg/ml and 3.56 mg/ml, respectively. The activity of imperatorin and xanthotoxin from A. archang...

The aim of this work was to study the antiproliferative effect of a tincture from fruits of Angelica archangelica and the active components using the human pancreas cancer cell line PANC-1 as a model. Significant dose-dependent antiproliferative activity was observed in the tincture with an EC50 value of 28.6 microg/ml. Strong antiproliferative act...

Objective. This study aimed to investigate the effect of SagaPro, a product derived from Angelica archangelica leaf, on nocturia. Material and methods. Sixty-nine male patients 45 years or older with at least two nocturnal voids were randomized to receive SagaPro or placebo in a double-blind design for 8 weeks. Voiding diaries were assessed befor...

Angelica archangelica fruits were collected from 64 locations around Iceland and analysed for furanocoumarins by high-performance liquid chromatography. The average furanocoumarin content was found to be 22.5 mg/g, ranging from 14.0 to 31.6 mg/g. Whereas imperatorin was the main compound in all samples, the order of other compounds was highly diver...

The aim of this work was to study the constituents and cytotoxicity of the essential oils from the fruits of Angelica archangelica growing in Iceland. Three samples of essential oils were prepared by steam distillation. Their composition was established with GC/MS. The effects of the oils were examined in PANC-1 human pancreas cancer cells and Crl...

Background: The purpose of this study was to examine the effect of a leaf extract from A. archangelica on the growth of Crl mouse breast cancer cells in vitro and in vivo. Materials and Methods: The antiproliferative activity of the extract was measured by H-3-thymidine uptake in the Crl cells in vitro. Twenty mice were injected with the Crl cells,...

The purpose of this study was to examine the effect of a leaf extract from A. archangelica on the growth of Crl mouse breast cancer cells in vitro and in vivo. Materials and The antiproliferative activity of the extract was measured by 3H-thymidine uptake in the Crl cells in vitro. Twenty mice were injected with the Crl cells, and 11 of them were f...

Sphingolipids, especially as elements of the sphingomyelin signal transduction cycle, are thought to play a significant role as second messengers and modulators of events in heart muscle cells. A possible modulatory role of sphingosine in signal transduction in the beta-adrenergic pathway in the heart was examined. Neonatal rat cardiomyocytes were...

Adaptation to chronic stress or repeated adrenergic stimulation, to dietary fat and ageing was accompanied by significant changes in fatty acyl chain profile of cell membranes in the heart. Changes in fatty acyl composition of membrane phospholipids preceded down-regulation of adrenoceptors or occurred simultaneously. Successful adaptation to stres...

Sphingolipids, especially as elements of the sphingomyelin signal transduction cycle, are thought to play a significant role as second messengers and modulators of events in heart muscle cells. A possible modulatory role of sphingosine in signal transduction in the β-adrenergic pathway in the heart was examined. Neonatal rat cardiomyocytes were inc...

The purpose of this study was to examine the influence of long-term feeding of dietary fat rich in either n-3 or n-6 fatty acids on the availability of arachidonic acid (20:4n-6) in major phospholipids of gastric mucosa in rats. Three groups of male Wistar rats were fed either a standard diet, a cod liver oil-enriched diet (10% by weight), or a cor...

The purpose of this study was to test the hypothesis that catecholamine induced down-regulation ofβ-adrenoceptors in cardiac muscle is facilitated by modifications of the lipid milieu in cellular membranes. The time course of down-regulation ofβ-adrenoceptors and changes in the fatty acid composition of phospholipids was examined in the rat heart d...

Unlabelled: The purpose of this study was to examine the availability of arachidonic acid in phosphatdidylcholine (PC) and phosphatidylethanolamine (PE) of mucosa and the stomach wall of adult male Wistar rats fed a standard diet. There were significant differences in the fatty acid composition of PC and PE between various parts of the stomach. Th...

The purpose of this study was to examine changes in fatty acyl chain composition of major cardiac phospholipids in relation to down-regulation of β-adrenoceptors during various forms of stress or chronic adrenergic stimulation. Analysis of the fatty acid profile of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in sarcolemma or cardiac...

The purpose of this study was to examine the influence of ageing on the alterations in binding characteristics of adrenoceptors and membrane phospholipid fatty acids in rat heart following repeated administration of epinephrine. The maximal number of binding sites (Bmax) and dissociation constant (Kd) of [3H]prazosin and [3H]dihydroalprenolol bindi...

The purpose of this study was to examine the influence of ageing on the alterations in binding characteristics of adrenoceptors and membrane phospholipid fatty acids in rat heart following repeated administration of epinephrine. The maximal number of binding sites (Bmax) and dissociation constant (Kd) of [3H]prazosin and [3H]dihydrpalprenolol bindi...

The purpose of this study was to examine changes in binding properties of alpha 1-adrenoceptors, beta-adrenoceptors and L-Ca channels in rat heart muscle in relation to changes in the lipid environment within the membrane, i.e. fatty acyl chain composition of membrane phospholipids, occurring during repeated adrenergic stimulation. The effect of da...

Modifications of membrane phospholipids and binding characteristics of adrenoceptors by hydrocortisone and epinephrine were examined in sarcolemmal preparation from rat heart muscle. The influence of hydrocortisone and epinephrine on the fatty acid composition of membrane phospholipids and the affinity (1/Kd) and number of binding sites (Bmax) of a...

Modifications of membrane phospholipids and binding characteristics of adrenoceptors by hydrocortisone and epinephrine were examined in sarcolemmal preparation from rat heart muscle. The influence of hydrocortisone and epinephrine on the fatty acid composition of membrane phospholipids and the affinity () and number of binding sites (Bmax) of α1- a...

Male Wistar rats were fed a standard diet or diets supplemented with 10% butter, 10% corn oil, or 10% cod liver oil from the age of 2 mo. At 7 and 24 mo of age, the fatty acid composition of total phospholipids was determined in ventricular crude sarcolemma preparations; binding capacity and affinity (1/Kd) of [3H]dihydroalprenolol and [3H]nitrendi...

A randomized crossover study was carried out to investigate the fatty acid profile and concentrations of plasma lipids in male patients with myocardial infarction (MI) who supplemented their diet with 20 ml cod liver oil daily for 6 weeks. Subjects were divided into two groups, A and B. Group A received cod liver oil daily for 6 weeks after hospita...

The preparation of triglycerides highly enriched with n-3 polyunsaturated fatty acids, EPA and DHA in particular, via interesterification of cod liver oil and free fatty acid or ethyl ester concentrates catalyzed by an immobilized 1,3-specific lipase from Mucor miehei, is described.

The purpose of this paper is to discuss the role of n-6 and n-3 polyunsaturated fatty acids in coronary heart disease (CHD). The level of n-6 and n-3 fatty acids in plasma and cardiac phospholipids was examined in relation to CHD in man. The fatty acid profile of cardiac phospholipids was also examined in relation to various risk factors of CHD, su...

The purpose of this paper is to describe the dynamics of n-3 and n-6 polyunsaturated fatty acids in major phospholipids of heart muscle. The profile of n-3 and n-6 fatty acids was examined in rats in relation to various risk factors of coronary heart disease such as stress (catecholamines), ageing and dietary fat. The level of n-3 and n-6 fatty aci...

The effect of epinephrine on the fatty acid composition of heart muscle phospholipids was examined in rats fed diets containing 10% by weight of butter, corn oil, or cod liver oil. Repeated administration of epinephrine caused elevation of docosahexaenoic acid in phosphatidylcholine and phosphatidylethanolamine and a corresponding decrease in linol...

The effect of dietary cod liver oil, corn oil or butter upon the lipid composition of cardiac sarcolemma and the activity of sarcolemmal Na+, K+ ATPase was examined in male Wistar rats. The cod liver oil diet caused significant changes in the fatty acid composition of the major phospholipids of sarcolemma, phosphatidyl choline and phosphatidyl etha...

The relationship between non-esterified fatty acids (NEFA) in serum and heart muscle was examined in 15 patients who died of myocardial infarction (MI) and seven people who died suddenly in accidents. There was no correlation between NEFA levels of serum and non-infarcted cardiac muscle in patients with fatal MI. No significant difference was encou...

ABSTRACT The relationship between non-esterified fatty acids (NEFA) in serum and heart muscle was examined in 15 patients who died of myocardial infarction (MI) and seven people who died suddenly in accidents. There was no correlation between NEFA levels of serum and non-infarcted cardiac muscle in patients with fatal MI. No significant difference...

The fatty acid composition of phospholipids and triglycerides in heart muscle was examined in normal and alloxan-diabetic male Wistar rats. In diabetes the major phospholipids, phosphatidyl choline and phosphatidyl ethanolamine, showed significant changes in fatty acid composition, whereas cardiolipin and phosphatidyl serine + phosphatidyl inositol...

The fatty acid composition and concentrations of serum phospholipids (PL) were examined in 14 normal subjects (NS), 10 patients with coronary heart disease (CHD) and stable angina pectoris, and in 12 patients with acute, fatal myocardial infarction (MI). The NS and patients with CHD and stable angina pectoris were matched with respect to age, heigh...

Stress is considered one of the pathogenic factors in development of coronary artery disease. Increased sympathetic activity and elevated plasma levels of catecholamines influence markedly cardiac function and myocardial metabolism. Changes in function of the heart induced by exogenous or endogenous catecholamines during stress or significant chang...

The fatty acid composition of rat heart phospholipids was examined during the neonatal and postnatal period. The rats were killed on days 1, 7, 14 and 21 after birth and at the ages of 2 and 6 months. The fatty acyl chain composition of the two major phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE) changed significantly dur...

Rats were injected subcutaneously for 2 weeks with increasing amounts of norepinephrine. The lipid composition of the heart muscle was examined for nearly 2 months. The treatment caused major changes in fatty acyl chain composition of myocardial phosphatidylethanolamine and phosphatidylcholine. In these phospholipids, linoleic acid was decreased to...

The purpose of this study was to examine the fatty acid composition and content of phospholipids, and free fatty acids in human heart muscle samples obtained at autopsy from people that died suddenly in accidents and from people that died suddenly from heart disease, with or without coronary artery disease.

The effect of noradrenaline on fatty acyl chain composition of the rat heart phospholipids was studied in vivo. The rats received increasing amounts of noradrenaline for 15 days. The noradrenaline stress caused significant alterations in the fatty acyl chain composition of the two major phospholipids in heart muscle, whereas the phospholipid conten...

The polyene fatty acid compostition of cardiac phospholipids is modified by a) dietary cod liver oil, b) norepinephrine, c) chronic administration of nicotine to animals fed a high cholesterol diet. Polyene fatty acids stimulate microsomal oxydation of epinephrine to cardiotoxic adrenochrome. Adrenochrome stimulates microsomal peroxydation or oxyge...

Cardiac membranes are dynamic structures in a state of constant activity. The phospholipids play an important role in structure and function of membranes and the composition of these phospholipids is continuously modified by external and internal factors, such as diet or hormones. The role of dietary fat in cardiovascular disease has thus far prima...

Modification of the fatty acid composition of cardiac phospholipids and neutral lipids was studied in rats fed a diet containing 10% cod liver oil. The results reflect the dynamic state of esterified fatty acids in neutral lipids and phospholipids of heart muscle. In cardiac neutral lipids there was a moderate but significant increase in exogenous...

Significant alterations in fatty acyl composition of cardiac phospholipids and neutral lipids are induced by dietary cod liver oil in the rat. Increased dietary availability of docosahexaenoic acid (22:6 omega3) leads to extensive replacement of linoleic acid (18:2omega6) and arachidonic acid (20:4omega6) in phospholipids. Dietary cod liver oil (10...

The fatty acid composition of cardiac membrane lipids is influenced by age, sex, diet and other factors. The relative amounts of various polyunsaturated fatty acids in cardiac lipids influence markedly the development of myocardial necrosis and mortality following overstimulation with isoproterenol. The availability and metabolism of arachidonic ac...

1. Dietary lipids modify fatty acid composition of cardiac lipids. Polyunsaturated fatty acids replace less unsaturated fatty acids in phospholipds. 2. Mortality following isoproterenol-stimulation increase with decreasing amount of arachidonic acid in cardiac phospholipds. 3. In normal human heart muscle the ratio of essential, omega-6/nonessentia...

A marked, reversible decline in cardiac norepinephrine (NE) stores was noted after experimental myocardial infarction. Uptake and accumulation of tracer dose of dl-[7-14C]norepinephrine appeared to be unchanged as well as the rate of degradation. Despite marked variations in pool size the subcellular distribution appeared to be unchanged, and no pr...

Administration of isoproterenol induces changes in phospholipids of heart muscle membranes. Longer and more unsaturated fatty acids replace shorter and less unsaturated fatty acids. Dietary polyunsaturated fatty acids, i.e., C22:6, replace C18:2 and C20:4 in phospholipids of heart muscle. Increased sensitivity to isoproterenol and increased myocard...

Im Gefolge eines Herzinfarkts kommt es zu einem Anstieg des Noradrenalinspiegels im Plasma; gleichzeitig wird eine vermehrte Ausscheidung im Harn beobachtet. Diese Befunde werden einer verstärkten Aktivität des sympathischen Nervensystems zugeschrieben, der man eine unterstü tzende Rolle zur Erhaltung der Funktion des Restmyokards beimißt In der vo...

Authors' synopsis: Changes in metabolite and high-energy phosphate levels in the non-infarcted portion of the left ventricle were studied in dogs from one to 10 days after coronary artery ligation. There was a marked fall in the adenosine triphosphate (ATP) levels in the non-infarcted region of the left ventricle 24 hr after infarction; a progressi...

Changes in catecholamine and energy metabolism in the non-infarcted portion of the left ventricle were studied in dogs during the postinfarction period. Metabolic changes in the non-infarcted myocardium were correlated with the functional status of the left ventricle. There was a marked fall in the ATP levels in the non-infarcted region of the left...

Serial determinations of the norepinephrine content in all four chambers of the canine heart were carried out following surgical myocardial infarction. The observed changes were related to myocardial function and metabolic alterations. Normal left ventricular muscle contained 0.98 μg NE per gram tissue, but following coronary artery occlusion, the...

Die Bedeutung der energiereichen Phosphate Adenosin-5′-triphosphat (ATP) und Creatinphosphat (CP) für die mechanische Funktion des Herzmuskels ist aus vielen Untersuchungen bekannt (5, 8, 9, 16). Über die akuten Veränderungen des Herzstoffwechsels, insbesondere der energiereichen Phosphate nach experimentellem Koronarverschluß liegen zahlreiche Unt...

Following surgical myocardial infarction in dogs, a marked decline in cardiac norepinephrine stores has been observed. In an attempt to elucidate the mechanism of the NE-depletion, the uptake, degradation, and subcellular distribution of norepinephrine in the canine myocardium were determined after myocardial infarction. The subcellular distributio...

The relationship between ATP and creatine phosphate (CP) in heart muscle was studied in two experimental models: (a) in the intact area of the infarcted heart at various levels of energy rich phosphates; and (b) in acutely ischemic heart muscle. Myocardial ischemia and infarction was produced in dogs by ligation of coronary arteries. Biopsy samples...

The mechanism of tissue repair in infarcted heart muscle consists of two parallel phases, the catabolic phase of degradation of dead and severely damaged heart muscle cells and the anabolic phase of fibroblastic proliferation and synthesis of scar tissue replacing the necrotic muscle.

Experimental myocardial infarction was produced in 32 mongrel dogs. The changes in activity of four lysosomal enzymes (acid phosphatase, glucuronidase, deoxyribonuclease, and γ-glutamyl-transpeptidase) were examined in the soluble and the particle-bound fraction. The pattern of changes in free and particle-bound enzyme activity observed was similar...

The activity of γ-glutamyl-transpeptidase was determined serially in patients with acute myocardial infarction up to 32 days after the onset of chest pain. Peak enzyme activity was found in all patients between the eighth and eleventh day after infarction. Some patients showed a rise in serum activity 48 hr after infarction. In 33 mongrel dogs with...

The catalytic polarographic activity of histidine, imidazole, imidazole acetic acid, histamine, 3-methyl histidine and 1-methyl histidine was studied in cobaltous ammoniacal medium.The effect of pH, concentration and temperature upon the electrode potential and catalytic current of the polarographic waves of histidine were examined, as well as the...

The tissue content of energy-rich phosphates and glycolytic metabolites and the activity of myocardial enzymes were examined in the dog after producing myocardial infarction by ligating branches of the anterior descending and circumflex coronary arteries. The pattern of systolic fiber movement shown by a strain-gauge assembly differentiated ischemi...

The metabolism of infarcted canine heart muscle was studied by examining the enzyme profile of infarcted and normal tissue; oxidative and glycolytic metabolism, as expressed in ATP and lactate levels of the infarcted muscle; and lipid synthesis and fatty degeneration of the infarcted muscle. The activities of heart muscle enzymes were assayed durin...

The effect of chronic alcohol administration (10 weeks) on the glyceride content and enzyme profile of heart muscle, brain, and liver was examined in the dog. A significant increase (2.8-fold) in glyceride content of cardiac muscle was observed in the alcohol consuming animal, without concomitant changes in myocardial enzyme profile. Chronic alcoho...

The catalytic polarographic activities of thiamine, oxgythiamine, thiamine monophosphate and thiamine pyrophosphate were studied during the intramolecular rearrangement of these substances in a basic solution. The halflife of the polarographic maxima were 6 min for thiamine, 19 min for thiamine pyrophosphate, 35 min for thiamine monophosphate and 1...

The activities of heart muscle enzymes were assayed during tissue repair following experimental myocardial infarction in the dog. The activities of 10 enzymes were determined in normal heart muscle and in the center and periphery of infarcted muscle. A significant increase in hexosemonophosphate-shunt activity was observed in infarcted tissue 5 h a...

The rate of myocardial protein synthesis was studied in hearts of rabbits with experimentally produced cardiac hypertrophy and treatment with actinomycin D and puromycin as well as in animals maintained on a protein-free diet. Actinomycin D and puromycin inhibited myocardial incorporation of glycine-2-C¹⁴ only if protein synthesis was stimulated by...

The polarographic characteristics of pure protein fractions appear to be specific in nature. These techniques therefore could be utilized as useful tools for studying normal and abnormal serum proteins.

Left heart failure was produced in rabbits by constriction of the ascending aorta, Incorporation of Cystine-S35 into cardiac myosin, water soluble enzymes, plasma protein and skeletal muscle protein was studied. There were no significant differences between the rate of synthesis of left ventricular myosin and the other protein fractions obtained un...

The effect of acetoacetate infusion on myocardial metabolism was studied in 13 dogs at varying concentrations of acetoacetate. Acetoacetate was extracted by the myocardium at arterial levels of from 1 to 54 mg/100 ml. At arterial levels of above 60 mg/100 ml, extraction of acetoacetate by the heart was very small. Considerable amounts of the infuse...

The activities of intracellular cardiac enzymes were determined in necropsy material from patients with normal heart muscle, patients who had died from congestive heart failure or arteriosclerotic heart disease. The enzymes chosen for this study were selected as representatives of three metabolic pathways: the Embden-Meyerhof pathway (lactate dehyd...

The effect of myocardial infarction upon protein and nucleic acid synthesis of the heart was studied. Myocardial infarction was produced in dogs by ligation of branches of the anterior or posterior descending coronary artery. The rate of incorporation of glycine-2-C¹⁴ into heart muscle protein was studied over a period of six weeks. The infarcted t...

Studies on the circulation and on cardiac metabolism were carried out during intravenous infusion of norepinephrine in 15 human subjects. There was a marked increase in the myocardial extraction of free fatty acids. No significant change in coronary blood flow or myocardial oxygen consumption was observed. Coronary vascular resistance and myocardia...

The rate of myocardial protein synthesis was studied in the hearts of normal rabbits and of animals with experimentally produced cardiac hypertrophy and acute and chronic myocardial failure. Cardiac hypertrophy was accompanied by an increase in protein synthesis; however, there was no increased myocardial protein turnover rate. In acute heart failu...