Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.5 (5'-nucleotidase)
 3,167 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

These experiments were designed to determine whether hypercholesterolemia and the accumulation of cholesterol or cholesteryl esters in rabbit carrageenan granuloma macrophages might influence selected markers of macrophage activation. Granulomas induced by subcutaneous injection of carrageenan into rabbits were harvested after 4, 14, and 28 days. Macrophages were isolated from granuloma tissues by collagenase digestion and cultured overnight. Secretion of lysosomal beta-glucuronidase, membrane 5'-nucleotidase, cellular plasminogen activator, and superoxide anion generation were measured as markers of activation. beta-Glucuronidase activity secreted into the media by granuloma macrophages from normocholesterolemic (NC) and hypercholesterolemic (HC) rabbits showed a trend toward an increase with time between 4 and 14 days in both groups. This was confirmed in a separate experiment with a significant increase by 14 days, together with a significantly greater secretion by NC macrophages and a significantly elevated level of cellular beta-glucuronidase activity in NC relative to HC macrophages. Activity of the membrane ectoenzyme 5'-nucleotidase was minimal in lysates of NC or HC macrophages, in contrast to freshly isolated human monocytes, indicating that both NC and HC granuloma macrophages were highly activated. Cellular plasminogen activator activity was significantly increased between 4 and 14 days, and was significantly greater in HC than in NC macrophages at 14 days. Stimulation of macrophages with phorbol myristate acetate increased superoxide anion generation by both NC and HC macrophages; however, no difference in superoxide anion generation was observed between macrophages from NC and HC rabbits. On the basis of the 5'-nucleotidase findings, it is concluded that both the NC and HC granuloma macrophages are highly activated, and further that hypercholesterolemia does not enhance macrophage generation of superoxide anion, either spontaneously or as the result of phorbol myristate acetate stimulation. Although hypercholesterolemia results in macrophage activation in terms of an increased cellular plasminogen activator activity, the secretion of the lysosomal enzyme beta-glucuronidase is diminished. Thus, hypercholesterolemia associated with macrophage cholesterol and cholesteryl ester accumulation has no consistent overall influence on activation, a finding of potential importance in the context of atherogenesis.
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PMID:Influence of hypercholesterolemia and cholesterol accumulation on rabbit carrageenan granuloma macrophage activation. 283 4

Experiments on 67 rabbits were performed to examine the injured external cell membranes of the vascular wall, appearing in the blood flow in the course of the development of alimentary hypercholesterolemia. The time of the appearance in the blood plasma of the external cell membranes was judged from the activity of their specific marker, 5'-nucleotidase. An abrupt increase in 5'-nucleotidase activity was disclosed in the blood plasma at the height of hypercholesterolemia. The latter circumstance served as an objective criterion for injury to ther external cell membranes and might be regarded as a risk factor in thrombus formation.
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PMID:[Cytoplasmic membrane damage and thromboplastinemia in hypercholesterolemia]. 627 Dec 93

The role of hypercholesterolemia as a factor modulating functional activity of macrophages during the growth of syngeneic transplanted 22a hepatoma in mice was studied. Starting from day 21 after inoculation of tumor cells we observed the development of hyperlipoproteinemia paralleled by an increase in macrophage activity parameters. The total serum cholesterol content and production of nitroxide anions by macrophages were in positive correlation on days 14-35 of tumor growth. We hypothesized that the development of hypercholesterolemia at the late stages of some tumor growth is a factor stimulating production of nitrites and 5'-nucleotidase activity.
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PMID:Effect of hyperlipoproteinemia on functional activity of peritoneal macrophages during tumor growth. 1545 88

Extracellular nucleotides and nucleosides act as signaling molecules involved in a wide spectrum of biological effects. Their levels are controlled by a complex cell surface-located group of enzymes called ectonucleotidases. There are four major families of ectonucleotidases, nucleoside triphosphate diphosphohydrolases (NTPDases/CD39), ectonucleotide pyrophosphatase/phosphodiesterases (E-NPPs), alkaline phosphatases and ecto-5'-nucleotidase. In the last few years, substantial progress has been made toward the molecular identification of members of the ectonucleotidase families and their enzyme structures and functions. In this review, there is an emphasis on the involvement of NTPDase and 5'-nucleotidase activities in disease processes in several tissues and cell types. Brief background information is given about the general characteristics of these enzymes, followed by a discussion of their roles in thromboregulatory events in diabetes, hypertension, hypercholesterolemia and cancer, as well as in pathological conditions where platelets are less responsive, such as in chronic renal failure. In addition, immunomodulation and cell-cell interactions involving these enzymes are considered, as well as ATP and ADP hydrolysis under different clinical conditions related with alterations in the immune system, such as acute lymphoblastic leukemia (ALL), B-chronic lymphocytic leukemia (B-CLL) and infections associated with human immunodeficiency virus (HIV). Finally, changes in ATP, ADP and AMP hydrolysis induced by inborn errors of metabolism, seizures and epilepsy are discussed in order to highlight the importance of these enzymes in the control of neuronal activity in pathological conditions. Despite advances made toward understanding the molecular structure of ectonucleotidases, much more investigation will be necessary to entirely grasp their role in physiological and pathological conditions.
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PMID:NTPDase and 5'-nucleotidase activities in physiological and disease conditions: new perspectives for human health. 1880 12