Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0004153 (atherosclerosis)
 77,401 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The activity of lecithin: cholesterol acyltransferase (LCAT) and the plasma lipoprotein concentrations of elite athletes from 8 selected sports (volleyball, judo, sprinting, wrestling, throwing, cycling, water polo and tennis) were determined and compared with those of a sedentary control group. Plasma LCAT activity levels in the athletes were significantly 2.2-7.0 times higher than in the controls in most sports (p less than 0.01). Judo, sprinting, wrestling and throwing had comparable LCAT values while tennis, volleyball and cycling were considerably higher. HDL-C concentration was significantly higher than controls in the water polo (p less than 0.05), cycling and volleyball (p less than 0.01) groups. Percentage lipoprotein distribution in the athletes in all sports except tennis, throwing and wrestling were similar to the controls. The differences among groups in LCAT activity may be related to the effect of physical exercise and training adaptations to lipid metabolism. This may be of importance when judging the benefit of exercise for atherosclerosis protection.
 ...
PMID:Plasma lecithin: cholesterol acyltransferase activity in elite athletes from selected sports. 322 65

Earlier studies have established that the analgesic and anti-inflammatory compound, dimethyl sulfoxide (DMSO), was effective in preventing atherosclerosis in cholesterol-fed rabbits. In the present studies, the effect of DMSO on existing atherosclerotic lesions in cholesterol-fed rabbits was investigated. Rabbits were placed on an atherogenic diet containing 1% cholesterol for a period of 10 weeks. At the end of the 10-week period, the rabbits were randomly divided into two groups: one group was placed on a control diet consisting of regular rabbit chow for an additional 12-week period, whereas the remaining group was continued on the atherogenic diet. During this period half of the rabbits in each of these groups were treated with DMSO (approximately 5 g/kg) which was included in their drinking water. Food consumption and fluid intakes were monitored daily and body weights at weekly intervals. Total serum cholesterol levels were measured at periodic intervals. Lipid deposits in the eye which accompany atherosclerosis were examined before and at 12 weeks after institution of the new dietary regimens. At the end of 12 weeks, all rabbits were killed and the thoracic aortas were examined for changes in the extent of atherosclerosis. Food consumption and body weight increased in rabbits on the control diet and in those treated with DMSO. Those maintained on the atherogenic diet showed little change in food intake or body weight. Fluid intake was significantly elevated in all rabbits placed on DMSO. Serum cholesterol levels returned to normal in all rabbits on the control diet. Serum cholesterol levels remained unchanged in rabbits kept on the atherogenic diet alone.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Cholesterol-induced atherosclerosis in the rabbit: effect of dimethyl sulfoxide on existing lesions. 325 28

In separate experiments, we fed 30 male and 25 female baboons a diet enriched in cholesterol and saturated fat for periods of 3.3 and 2.6 years. Using operant conditioning with water rewards, we trained the animals to puff on smoking machines in a human-like manner. Half of the animals smoked more than 40 cigarettes per day, while the remaining animals (controls) puffed air. Initially, the diet produced twofold (males) and threefold (females) elevations from baseline levels in serum cholesterol concentrations, but over the course of the experiments, the serum cholesterol decreased to 1.5 (males) and 2.0 (females) times baseline levels in both cigarette smokers and controls. Blood carbon monoxide concentration, plasma thiocyanate concentration, and urine cotinine concentration were significantly greater in smokers than in controls. Responses to smoking in males included lymphocytosis, elevated fasting blood glucose concentration, and decreased seminal vesicle weight. In females, hemoglobin and mean corpuscular hemoglobin concentrations were elevated. The extent of atherosclerosis was examined after 2.8 (males) and 1.6 (females) years of smoking. Among males, the extent of lesions in carotid arteries was significantly greater in smokers than in controls, but there were no significant differences in atherosclerosis in the aorta or the brachial, iliac-femoral, or coronary arteries. Among females, there were no significant differences in atherosclerosis between smokers and controls in any artery. These experiments show little effect of 2 to 3 years of cigarette smoke inhalation and concurrent modest elevation of blood carboxyhemoglobin on experimental atherosclerosis in the presence of moderate hyperlipidemia.
 ...
PMID:Cigarette smoking, dietary hyperlipidemia, and experimental atherosclerosis in the baboon. 333 49

This review summarizes the evidence that the physical properties of lipids which accumulate in the intima play major roles in the progression and regression of lesions of atherosclerosis. All of the three major classes of lipids that accumulate in lesions (phospholipids, cholesterol, and cholesterol esters) are water insoluble. Phospholipids and cholesterol esters are almost mutually insoluble, but cholesterol, a crystalline solid at 37 degrees C, has considerable solubility in phospholipid bilayers and cholesterol esters. In normal infant intima, cholesterol is solubilized by phospholipid membranes. During fatty streak development, groups of cells are stimulated to take up more cholesterol than they excrete. The excess cholesterol is biochemically converted to cholesterol ester, which separates as droplets to form foam cells. Some fatty streaks then undergo a transition to an intermediate lesion containing excess cholesterol which is carried in cholesterol-supersaturated membranes and droplets. When nucleation of this excess cholesterol occurs, it precipitates as crystals; their formation coincides with the onset of necrosis and plaque formation. The hallmark of plaque is the presence of inert cholesterol crystals. They appear to form from hydrolysis of the older deposits of cholesterol esters in the base of intermediate lesions. Thus, the lipids in plaques are stratified, with recently deposited cholesterol esters present in the luminal part of the intima and older deposits in the deeper regions. When plasma cholesterol is lowered below about 150 mg/dl, lipids are mobilized from lesions and regression gradually occurs. Early in the regression process, cholesterol esters are reduced at least partly by hydrolysis to yield cholesterol, some of which may crystallize and inhibit rapid regression. After prolonged periods of low plasma cholesterol, cholesterol esters and foam cells disappear and crystalline cholesterol gradually dissolves, leading to true regression.
 ...
PMID:George Lyman Duff memorial lecture. Progression and regression of atherosclerotic lesions. Insights from lipid physical biochemistry. 334 56

We investigated the effects on blood pressure of 5% taurine administered prenatally or postnatally via maternal parents in stroke-prone spontaneously hypertensive rats (SHRSP). Prenatal and/or postnatal administration of taurine produced a blood pressure reduction in the offspring until at least 3 months of age. Furthermore, offspring exposed to high concentrations of taurine through the placenta during the prenatal period and also for 1 month after birth via maternal milk, showed a greater reduction in blood pressure than the group given taurine prenatally but not postnatally. The stroke-prone SHR were fed a high-fat cholesterol and low-protein diet containing 1% methionine or with 3% lysine in drinking water, and effects of the dietary amino acids on the development of atherogenesis were investigated. Intake of additional 1% methionine or 3% lysine had marked preventive effects on atherogenesis in the cerebral and mesenteric arteries in SHRSP. Therefore, early dietary intake of sulphur amino acids delays the onset of hypertension and attenuates the development of both severe hypertension and atherosclerosis in SHRSP.
 ...
PMID:Effects of sulphur amino acids on the development of hypertension and atherosclerosis in stroke-prone spontaneously hypertensive rats. 348 15

We have examined whether the toxic effects of homocysteine on cultured endothelial cells could result from the formation and action of hydrogen peroxide. In initial experiments with a cell-free system, micromolar amounts of copper were found to catalyze an oxygen-dependent oxidation of homocysteine. The molar ratio of homocysteine oxidized to oxygen consumed was approximately 4.0, which suggests that oxygen was reduced to water. The addition of catalase, however, decreased oxygen consumption by nearly one-half, which suggests that H2O2 was formed during the reaction. Confirming this hypothesis, H2O2 formation was detected using the horseradish peroxidase-dependent oxidation of fluorescent scopoletin. Ceruloplasmin was also found to catalyze oxidation of homocysteine and generation of H2O2 in molar amounts equivalent to copper sulfate. Finally, homocysteine oxidation was catalyzed by normal human serum in a concentration-dependent manner. Using cultured human and bovine endothelial cells, we found that homocysteine plus copper could lyse the cells in a dose-dependent manner, an effect that was completely prevented by catalase. Homocystine plus copper was not toxic to the cells. Specific injury to endothelial cells was seen only after 4 h of incubation with homocysteine plus copper. Confirming the biochemical studies, ceruloplasmin was also found to be equivalent to Cu++ in its ability to cause injury to endothelial cells in the presence of homocysteine. Since elevated levels of homocysteine have been implicated in premature development of atherosclerosis, these findings may be relevant to the mechanism of some types of chronic vascular injury.
 ...
PMID:Endothelial cell injury due to copper-catalyzed hydrogen peroxide generation from homocysteine. 351 79

Atherosclerosis with its complications is the most important health problem affecting American adults. The levels of serum cholesterol, of high and low density lipoproteins, and of apolipoproteins A1, A2, and B are major risk factors for the development of atherosclerotic lesions. Animal studies suggest that chlorinated drinking water may elevate the serum cholesterol. Studies are too limited to confirm or refute this effect in humans. Since millions of humans have and have had daily exposure to chlorinated drinking water, it is essential to study the effects of such exposure on human lipid metabolism. We have begun a protocol to discover whether consuming chlorinated drinking water elevates serum cholesterol and the other lipid components of blood known to be associated with atherosclerosis. This protocol has been designed to improve the chance of observing an effect while preserving the ability to generalize the data.
 ...
PMID:Effects of chlorinated drinking water on human lipid metabolism. 354 3

The process of cholesterol extraction from the blood of rabbits with experimental atherosclerosis was investigated, with the following reinjection of the blood with reduced amount of cholesterol. Liquid membranes were applied to extract free cholesterol. Emulsion consisting of blood-compatible membrane (oil and sorbitan oleate) and the inner phase (water solution of digitonin) was used as an extractant. The average degree of cholesterol extraction was 23.4%. Pretreatment of the emulsion, its composition and the way of preparation make it possible to perform the extraction from the blood without a considerable increase in the degree of hemolysis.
 ...
PMID:[Extraction of cholesterol from the blood using multiple emulsions]. 359 47

Adduction of ethylene glycol moieties to the 3-hydroxy position of cholesterol produces polyoxyethylated cholesterol (POEC), a water-soluble compound that suppresses cholesterol synthesis and esterification in cultured human fibroblasts. Feeding Sprague-Dawley rats a diet containing 2% (wt/wt) POEC with 10 ethoxy groups resulted in a 3-fold increase in hepatic 3-hydroxy-3-methylglutaryl-CoA reductase activity compared to activity in rats pair-fed a diet of standard rat chow. POEC with an average of 20 ethoxy groups (POEC-20) caused comparable changes in hepatic [2-14C]acetate incorporation into non-saponifiable lipids under ad libitum feeding conditions, significantly reduced cholesterol absorption (18% vs 57%), and increased fecal excretion of neutral steroids (5.1 vs 2.0 mg/g food intake). POEC-20 also reduced cholesterol absorption in rats fed a diet enriched with 2% cholesterol (11% vs 31%). Histologic studies of intestinal mucosa and hepatic tissues from rats fed POEC showed no pathologic changes. These experiments indicate that POEC reduces cholesterol absorption and causes compensatory increases in hepatic cholesterol synthesis.
Atherosclerosis 1987 Apr
PMID:The effects of polyoxyethylated cholesterol feeding on hepatic cholesterol synthesis and intestinal cholesterol absorption in rats. 360 8

The lipid constituents in native low-density lipoproteins (LDL), ultra-water-soluble LDL (UWS-LDL), and aortic intimal tissues were compared. These lipoproteins were obtained from healthy persons and patients with atherosclerotic diseases. Also, aortic intimas were separated from arterial walls obtained within 5 hr after the donor's death. (1) From the native LDL, cholesterol esters (CE), triglycerides (TG), small amounts of free fatty cid (FFA), free cholesterol (CF), and phospholipids (PL) were demonstrable by iodine vapor on TLC, but from UWS-LDL the above lipids plus a new lipid (spot X) were observed between TG and FFA on TLC. And also, an unknown spot with the same Rf value as spot X was recognized on TLC of lipid extract from the atherosclerotic lesion, but not from the normal intima. (2) The production of spot X in UWS-LDL is probably related to the oxidation of lipids in native LDL. Also, the spot X in UWS-LDL and the spot X in the atherosclerotic lesions are probably related to the oxidation of CE in these lipids. (3) The existence of UWS-LDL is important to the initiation and probably the progression of atherosclerosis.
 ...
PMID:Comparison among lipid constituents in native LDL, ultra-water-soluble LDL, and vessel wall, and their significance in arteriosclerosis. 365 44


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>