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

Extracts of snake venom have been widely used for the treatment of vascular thrombotic diseases, yet the therapeutic mechanism is not clear. The effect of snake venom fractions on atherosclerosis in Japanese quail was studied. The venom of Agkistrodon halys was fractionated by DEAE-cellulose chromatography and the pooled protein fractions that resulted were injected intravenously into the quail with aortic atherosclerosis induced by dietary cholesterol. After 7 weeks of injections on every other day, the quail were killed, blood clotting times and serum cholesterol levels were determined, and aortic atherosclerosis and fatty liver were scored. The results showed that while no regression of atherosclerosis was observed, the lowering of serum cholesterol, prolonged blood clotting time and reduced fatty liver were significantly affected by the injection of one of the pooled protein fractions. This venom fraction contained two major protein components, one of which had arginine esterase activity. From this study we conclude that snake venom has little effect on the regression of atherosclerosis, but it prolongs blood clotting and lowers serum cholesterol.
Atherosclerosis 1990 Oct
PMID:Effect of snake venom of Agkistrodon halys on atherosclerosis and blood characteristics in Japanese quail. 228 93

Coronary arteries of 93 clinically healthy Finnish children of both sexes were collected from successive, medicolegal autopsies of victims of violent death. In the histological and histochemical study, local, cushion-type thickenings of the coronary walls were demonstrable in 47, i.e. 50 per cent, of the children, the occurrence increasing with age. The most prominent change was the splitting of the internal elastic membrane and the accumulation of smooth muscle cells, forming a new, musculo-elastic layer. Glycosaminoglycans appeared in the luminal parts of the thickenings. There was an average decrease in the succinate dehydrogenase reaction in the cushion area, implying a degenerative process. The increase in the reaction of "injury markers", acid phosphatase and esterase based on the increase of cells rich in these enzymes, indicated pathologic process. It was concluded that change of this kind, demonstrable early in childhood, may dispose coronary arteries to atherosclerosis.
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PMID:Histological and histochemical studies on local coronary wall thickenings (cushions) in Finnish children who died violently. Cardiovascular risk in young Finns? 230 49

Results are described of a histological and histoenzymatic investigation of visual nerves with a history during life of acute vascular optic neuropathy. It was found that in vascular pathology of the visual nerve due to atherosclerosis, both in the involved and clinically healthy eye different degrees of visual nerve atrophy develop due to sclerotic changes in the blood vessels. The genesis of vascular lesions and atrophy of the visual nerve is to a certain degree determined by immunological changes as evidenced by infiltration of the tissues around the vessels and in the nerve fibers by immunocompetent cells with a pronounced activity of unspecific esterase and acid phosphatase.
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PMID:[Morphoenzymatic changes of the optic nerve in cardiovascular diseases]. 258 47

It has been suggested that focal glomerulosclerosis (FGS) is analogous to atherosclerosis. Because monocytes and their derivatives are involved in the latter, these cells may be involved in the development of the former. To investigate this possibility a combined histochemical and ultrastructural study of FGS was done. Sections from 13 biopsies showing FGS were stained for either nonspecific esterase or lysozyme to detect monocytes and their derivatives. These include foam cells (lipid-containing macrophages) in which there was positive cytoplasmic staining for both nonspecific esterase and lysozyme. Twenty-one of 29 glomeruli (72%) with segmental sclerotic lesions contained monocytes and/or foam cells, whereas only 18 of 251 glomeruli (7%) without the lesions demonstrated these cells (p less than 0.0001). The mean number of monocytes and/or foam cells in segmentally sclerotic glomeruli was 2.0 +/- 1.7 compared with 0.2 +/- 0.3 for uninvolved glomeruli (p less than 0.01). In glomeruli with sclerotic lesions foam cells predominated over monocytes. Neutral lipid was observed focally and segmentally in 29 of 35 biopsies with FGS. Electron microscopy in 23 biopsies consistently demonstrated intracapillary cells with monocytic features but few foam cells in very early lesions characterized by epithelial cell changes but no or minor glomerular tuft alterations. With progression, the relative number of monocytes declined but foam cells were observed more frequently. These results suggest that monocytes and their derivatives are involved in the development of FGS.
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PMID:Monocytes and focal glomerulosclerosis. 279 89

Adhesion of leukocytes to the aortic endothelium was studied in specific pathogen-free (SPF) and conventional rats and in SPF rats with diet-induced hypercholesterolemia. Nonspecific esterase activity with alpha-naphthyl acetate as substrate was used to characterize the adhered cells. Phagocytic activity was determined by injecting i.v. 0.1-0.4 ml/100 g doses of Monastral blue B (MbB). Adhesion in SPF rats was 8 +/- 4 esterase (+) cells/mm2. Adhesion in conventional rats was of the same order except in 2 cases with antibodies to Mycoplasma pulmonis and Kilham rat virus, where adhesion was 44 and 68 esterase (+) cells/mm2, respectively. For all MbB doses studied, phagocytic activity arose in a percentage of the adherent cells, ranging from 5 to 85%. Rats fed the hyperlipidic diet for 15 days developed severe hypercholesterolemia and adhesion was drastically increased to 200-700 esterase (+) cells/mm2. Results indicate that: (1) spontaneous pathology in rats may produce an increased adhesion of leukocytes to the endothelium, and (2) phagocytic activity is only expressed in a fraction of the esterase (+) cells adhered to the endothelium.
Atherosclerosis 1989 Jan
PMID:Adhesion of leukocytes to the aortic endothelium of conventional, specific pathogen free (SPF) and hypercholesterolemic SPF rats. 293 Jun 16

To characterize the lipoprotein metabolism of lipid-filled cells of atherosclerotic lesions, uptake of 3,3'-dioctadecylindocarbocyanine (DiI)-labelled low density lipoprotein (LDL), acetylated LDL (Ac-LDL) and beta-very low density lipoprotein (beta-VLDL) was studied by fluorescence microscopy and flow cytometry in primary cultures of enzymatically dispersed aortic cells from cholesterol-fed rabbits. Most of the foam cells were identified as macrophages on the basis of Fc-receptors and high activities of nonspecific esterase and acid lipase, although cholesteryl ester (CE) inclusions were found by filipin staining also in smooth muscle cells (SMCs). During the culture only SMCs proliferated and were confluent in about 1 week. After incubation with DiI-Ac-LDL most macrophage foam cells were brightly fluorescent, but also many SMCs accumulated fluorescence. In SMCs, an excess of LDL inhibited the uptake of DiI-beta-VLDL and DiI-LDL, indicating that these lipoproteins were taken up by the apoB,E receptor; the activity of this receptor was low 2 days after cell isolation but increased considerably during SMC proliferation. DiI-beta-VLDL was not taken up by the macrophage foam cells until after 7 days' culture, when their CE content had decreased, reflecting a feed-back regulation of these receptors as well. Our results indicate that, in primary cultures of enzyme-dispersed cells from rabbit atherosclerotic lesions, most of the foam cells have lipoprotein receptors resembling those described in macrophages and that also many SMCs accumulate Ac-LDL.
Atherosclerosis 1988 Feb
PMID:Lipoprotein uptake in primary cell cultures of rabbit atherosclerotic lesions. A fluorescence microscopic and flow cytometric study. 334 44

The histological, ultrastructural, morphometrical and histochemical aspects of the arterial media were studied in young and aged SHR, and compared to normotensive Wistar Kyoto rats. The diffuse thickening was the most characteristic feature of the hypertensive media. It seems due to three processes: Early generalized hypertrophy of smooth muscle cells (smc); connective matrix neogenesis and smc proliferation, more evident in peripheral vasculature. The present paper discusses the following hypertensive tunica media changes in relation to the atherosclerotic process: the decrease in lipolytic esterase and cholinesterase activities; the activation of some lysosomal enzymes; the increase in collagen, glycosaminoglycan and elastin content; the increased media thickness; the modified smc behavior (migration, secretion, proliferation). These alterations might positively influence arterial susceptibility to atherosclerosis through reduced smc lipolytic activity; slowed transmural diffusion; perturbed efflux and aggravated media hypoxia.
Atherosclerosis 1987 May
PMID:Tunica media changes in the spontaneously hypertensive rat (SHR). 360 28

Atherosclerotic aortic intimas of cholesterol-fed rabbits were enzymatically dispersed into single cells by collagenase and elastase. And monocyte-macrophages (M phi) were separated from smooth muscle cells (SMC), using the ability of M phi to adhere to a plastic dish firmly even in the enzyme solutions. Round or oval, heavily lipid-laden cells, so-called foam cells (FC), belonged to the M phi fraction. M phi-FC showed very strong activity for non-specific esterase using alpha-naphthyl butyrate, while SMC showed little or no activity. Some of the FC were large and multinucleated (multinucleated giant foam cells). They also showed positive non-specific esterase staining and are thought to be derived from M phi. M phi-FC synthesized various proliferate in the medium and the number decreased gradually within several days. Some SMC were heavily lipid-laden; however, they retained their original spindle shape. SMC lost lipid droplets gradually as they proliferated to confluence. SMC from atherosclerotic lesions showed higher proliferative activity than those from normal-appearing medias of atherosclerotic aortas or control aortas. Almost no M phi-FC were obtained from the intima-medias of grossly normal portions of atherosclerotic aortas and control aortas. The present method will be useful for studying the role of these cells in the pathogenesis of atherosclerosis.
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PMID:Separation and characterization of macrophages and smooth muscle cells in rabbit atherosclerotic lesions. 366 43

Specific esterase isoenzyme patterns in plasma may be associated with responsiveness of serum cholesterol to dietary cholesterol. In rabbits and rats the presence and absence of a high-mobility, anodal esterase band on electrophoresis have been shown to be associated with hypo- and hyperresponsiveness, respectively. We fed for 28 days male mice of 7 inbred strains either a low-cholesterol, commercial diet or a diet containing 2% (w/w) cholesterol, 0.5% cholic acid and 5% olive oil. Feeding the high-cholesterol diet revealed marked inter-strain differences in the responses of plasma and liver cholesterol; the increases ranged from 21 to 129% and from 10 to 80-fold, respectively. There was no association between esterase isoenzyme patterns in plasma and the sensitivity to the high-cholesterol diet. The mean baseline plasma total esterase activity tended to be positively associated with the absolute response of plasma cholesterol to the high-cholesterol diet (r = 0.56; n = 7), but the positive relationship between the baseline concentration of the ES-1 component in plasma and the cholesterolemic response was stronger (r = 0.84; n = 7; P less than 0.05). The high-cholesterol diet caused a significant increase in plasma total esterase activities in 6 out of the 7 strains. Evidence is presented that the increase in plasma total esterase activity, which was associated with an increase in the activity and concentration of the so-called ES-2 isoenzyme, is the result of an enhanced release of esterases from the intestine, rather than from the liver. A significant, positive correlation was found between the baseline intestinal esterase activity and the cholesterolemic response after cholesterol feeding (r = 0.83; n = 7; P less than 0.05).
Atherosclerosis 1987 Feb
PMID:Esterases in inbred strains of mice with differential cholesterolemic responses to a high-cholesterol diet. 382 85

With an increasing interest in the role of the monocyte-macrophage in the pathogenesis of atherosclerosis and as a progenitor of plaque intimal foam cells, a model for the study of foam-cell differentiation in an extravascular environment has been developed. Granulomas were induced in 25 normocholesterolemic (NC) and 28 hypercholesterolemic (HC) rabbits by the subcutaneous injection of 15 ml of 1% carrageenan. Granuloma tissue was harvested at 4, 7, 14, and 28 days and studied by light and transmission electron microscopy. Macrophages and foam cells were isolated by enzymic dispersion with collagenase and cultured for further characterization by scanning electron microscopy, nonspecific esterase (NSE), and oil red O (ORO) staining. Granuloma macrophages from NC rabbits were consistently ORO-negative, contrasting with those from HC rabbits which were strongly ORO-positive, even at 4 and 7 days. With an increasing duration of exposure to hypercholesterolemia, macrophages accumulated increasing amounts of stainable lipid, and in the 28-day HC granulomas, large foam cells distended by lipid inclusions accounted for 70% of the cells present. This model has established that NSE-positive macrophages in HC granulomas accumulate lipid and assume the morphologic characteristics of atheromatous intimal foam cells.
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PMID:Evolution of foam cells in subcutaneous rabbit carrageenan granulomas: I. Light-microscopic and ultrastructural study. 396 33


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