heparitin-sulfate and Hypercholesterolemia

Glycosaminoglycans (GAGs) have a plethora of functions to play. They are widely present in extracellular matrix, cell surface and inside the cell. During pathological conditions remodeling of GAGs leads to modifications in their structure and functions. In the present work, peritoneal macrophages were isolated from normal, diabetic, and diet-induced hypercholesterolemic rats and evaluated in terms of GAGs and cytoadherence to various extracellular matrix (ECM) components. Peritoneal macrophages are known to play important roles in the control of infection and inflammation. Isolated GAGs were characterized as belonging to heparan sulfate/heparin class. There were quantitative changes in sulfated GAGs in diabetic and hypercholesterolemic groups when compared to normal rats. Dose-dependent changes in cytoadherence were observed only with respect to fibronectin in LPS-activated macrophages from diabetic animals but not with laminin and type IV collagen when compared to macrophages from normal rats. Cytoadherence was significantly decreased on treatment with heparinase indicating that cytoadherence was at least partly mediated by heparan sulfate/heparin class of GAGs. Global disaccharide composition analysis showed that GAGs from macrophages of diabetic animals had higher sulfation ratio when compared to that of control and hypercholesterolemic animals.

Topics: Animals; Cell Adhesion; Cell Membrane; Collagen Type IV; Diabetes Mellitus, Experimental; Diet, High-Fat; Dietary Fats; Extracellular Matrix; Fibronectins; Heparin; Heparitin Sulfate; Hypercholesterolemia; Laminin; Lipopolysaccharides; Macrophages, Peritoneal; Male; Primary Cell Culture; Rats; Rats, Wistar; Streptozocin; Sulfuric Acid Esters

We examined the vascular expression levels of extracellular superoxide dismutase (EC-SOD), a major antioxidant enzyme in the cardiovascular system, in patients with acute coronary syndromes.. Twenty-one consecutive patients with acute myocardial infarction (AMI), 14 patients with unstable angina, 11 patients with stable angina, and 20 control subjects were studied. The levels of vascular EC-SOD expression were assessed by the difference in plasma EC-SOD concentrations before and after intravenous heparan injection. In the patients with AMI, vascular EC-SOD expression (ng/mL) was significantly higher on day 1 after the onset of AMI (148+/-10) as compared with the control subjects (116+/-6, P<0.05). The vascular EC-SOD expression returned to the normal range on day 7 (104+/-8), and that level persisted thereafter. The vascular EC-SOD expression was also significantly higher in the patients with unstable angina (160+/-13) than in those with stable angina (122+/-10) or in the controls (116+/-6) (P<0.05 each). Moreover, in the patients with AMI, higher levels of vascular EC-SOD expression on day 1 were significantly associated with smaller myocardial infarct size (P<0.05).. This is the first clinical demonstration showing that vascular EC-SOD may be upregulated in acute coronary syndromes in humans in vivo. EC-SOD may play an important protective role against increased oxidative stress during acute ischemic coronary events.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Aging; Coronary Disease; Enzyme Induction; Female; Heparitin Sulfate; Humans; Hypercholesterolemia; Male; Middle Aged; Muscle, Smooth, Vascular; Myocardial Infarction; Oxidative Stress; Oxygen Inhalation Therapy; Prospective Studies; Superoxide Dismutase

We evaluated the effects of heparan-sulphate administration on clotting times, thromboelastographic parameters and serum thromboxane B2 levels in hypercholesterolemic rabbits with aortic atherosclerotic lesions (sudanophilic areas). 24 New Zealand male rabbits were divided into three groups of 8 animals each. Group A and B were fed a rabbit chow diet containing 0.7% of cholesterol whereas Group C was fed a standard rabbit diet without cholesterol. Group A was treated by subcutaneous route with 6 mg/kg/day of heparan sulphate. At the beginning of the study and after 3 and 6 months of treatment, serum cholesterol and thromboxane B2 levels were tested. Furthermore, at the end of the experiment, we evaluated plasma fibrinogen, aPTT, PT and TT values. The administration of heparan-sulphate in cholesterol fed rabbits produced: a reduction of plasma fibrinogen levels, without modifying aPTT and TT; a protective effect vs the lengthening in PT values, likely induced by cholesterol rich diet; a reduction of plasma thrombophilic activities and of aortic atheromasic involvement induced by dietetic cholesterol intake. However, increased serum thromboxane B2 levels, likely through a proaggregant activity were observed. We suggest that heparan-sulphate administration, in cholesterol fed rabbits, has a favourable effect on clotting parameters, while contrasting effects were found on platelet activity.

Topics: Animals; Arteriosclerosis; Blood Coagulation; Cholesterol, Dietary; Drug Evaluation, Preclinical; Heparitin Sulfate; Hypercholesterolemia; Male; Rabbits; Thromboxane B2; Time Factors

We compared the effects of mild hypercholesterolemia and repeated endotoxin infusions on the biochemical composition of aortic intima and inner media of 24 piglets divided into 4 groups 5 days after weaning: controls on normal diet (group I); normal diet and endotoxin (group II); fat-supplemented diet (group III); and fat-supplemented diet and endotoxin (group IV). It was found that mild hypercholesterolemia increased the concentration of arterial esterified cholesterol and the relative amount of the fraction containing chondroitin sulphates A and C in total glycosaminoglycans. Endotoxin infusions partly prevented the increase of serum cholesterol caused by the fat-supplemented diet but had no independent effect on the arterial biochemical composition; nor did they affect the biochemical changes caused by hypercholesterolemia. When the results of all groups were combined, chondroitin sulphates A and C showed a significant positive correlation with the concentration of arterial esterified cholesterol and the percentage of linoleic acid in arterial cholesteryl esters. Serum total cholesterol did not correlate with arterial cholesterol fractions, but the ratio of high density lipoprotein-cholesterol to total serum cholesterol showed a negative association with arterial esterified cholesterol. The present findings indicate that (1) mild hypercholesterolemia is atherogenic in young piglets, and (2) changes in arterial glycosaminoglycan composition might be one of the earliest biochemical alterations in atherogenesis.

Topics: Animals; Aorta, Thoracic; Arteriosclerosis; Cholesterol; Chondroitin Sulfates; Dermatan Sulfate; Diet, Atherogenic; Endotoxins; Glycosaminoglycans; Heparitin Sulfate; Hyaluronic Acid; Hypercholesterolemia; Lipids; Muscle, Smooth, Vascular; Phospholipids; Reference Values; Swine

Topics: Animals; Aorta; Arteriosclerosis; Cholesterol; Chondroitin; Diet, Atherogenic; Female; Glycosaminoglycans; Heparitin Sulfate; Histocytochemistry; Hyaluronic Acid; Hypercholesterolemia; Rabbits