Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.31 (beta-glucuronidase)
 7,680 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

Lipid peroxidation has been induced by means of an atherogenic diet causing hypercholesterolaemia, hypertriglyceridaemia, increased LDL and decreased HDL serum fractions in addition to the fatty degeneration, vacuolization of the liver cells and accumulation of malondialdehyde in the liver. Increased release of acid phosphatase and N-beta-glucuronidase was also observed pointing to cholesterol-induced lysosomal membrane damage. In response to pretreatment with, and simultaneous administration of, 6,6'-methylene bis (2,2-dimethyl-4-methane sulphonic acid sodium salt-1,2-dihydroquinoline) the signs and symptoms of fatty liver degeneration, the tissue, plasma and platelet malondialdehyde concentrations and the LDL serum fraction significantly decreased and HDL serum fraction increased. Lisosomal membrane stability was restored, resulting in physiological acid phosphatase and N-beta-glucuronidase activities. The pathological and clinical aspects of lipid peroxidation in several diseases of the digestive organs and the suggested therapeutic uses of non-toxic radical scavengers have been outlined.
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PMID:Liver lipid peroxidation induced by cholesterol and its treatment with a dihydroquinoline type free radical scavenger in rabbits. 653 29