Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.2.1.23 (beta-galactosidase)
 14,648 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is possible that one of the consequences of regular physical activity could be a change of vascular metabolism. We studied the effects of regular swimming activity on specific activities of aortic hydrolases of male rats. Enzymes included: neutral alpha-glucosidase and lysosomal beta-galactosidase, N-acetyl-beta-glucosaminidase, cathepsin C, acid alpha-glucosidase, and acid cholesteryl esterase. After 8 or 16 weeks of a 1-hour/day swimming protocol, specific activities of four of the six aortic enzymes studied were increased over control levels, increases ranging from 7 to more than 42%. Acid cholesteryl esterase was one of the enzymes most affected by the exercise, increasing 25-30% above control levels. An 8-week sedentary period, after 8 weeks of a swimming regimen, resulted in return of the activity of acid cholesteryl esterase, but not those of the other hydrolases, to control levels. Decreases in body weight, blood pressure, and serum lipid levels also occurred in the swimming rats. Weight reduction per se was excluded as an explanation for the increases in aortic enzymes or decrease in serum cholesterol found with swimming. These findings show that regular physical activity is yet another factor with discrete and significant effects on the catabolic activity of vascular tissue.
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PMID:Hydrolase activities in the rat aorta. III. Effects of regular swimming activity and its cessation. 11 28

Vascular disease in diabetics could arise in part from altered vessel wall catebolism. Specific activities of hydrolases in aortic smooth muscle cells from rats with streptozotocin-induced diabetes were measured. Enyzmes included: neutral alpha-glucosidase, alpha-mannosidase, and lysosomal N-acetyl beta-glucosaminidase, beta-galactosidase, cathepsin C, acid alpha-glucosidase, and acid cholesteryl esterase. After 4,8, and 11 weeks of diabetes, activities of all enzymes studied were decreased significantly in diabetic vessels, decreases ranging from 15% for cathepsin C to 62% for alpha-mannosidase. After 3 weeks of diabetes, insulin treatment for 1 week restored enzyme levels to normal. After 7 weeks of diabetes, 1 week of insulin treatment did not restore enzyme levels fully to normal (acid cholesteryl esterase was unchanged); 4 weeks of insulin did. Acid phosphatase and N-acetyl beta-glucosaminidase activities were reduced markedly in histochemical studies of diabetic aortas at all time periods and were restored by insulin treatment. Alloxan-induced diabetes gave results similar to those with streptozotocin. Significant decreases of aortic hydrolase activities, including those of lysosomes, occur in experimental diabetes mellitus and could contribute to accumulation of substrates in vascular smooth muscle cells.
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PMID:Hydrolase activities in the rat aorta. I. Effects of diabetes mellitus and insulin treatment. 14 80

Hypertension is an important risk factor for atherosclerosis and often occurs in association with diabetes mellitus. Specific activities of hydrolases in homogenates of aortas from rats with renal-clip hypertension, normotension following a period of hypertension, and hypertension combined with streptozotocin-induced diabetes mellitus were measured. Enzymes included: neutral alpha-glucosidase, and lysosomal N-acetyl-beta-glucosaminidase, beta-galactosidase, cathepsin C, acid alpha-glucosidase, and acid cholesteryl esterase. After 6 or 12 weeks of hypertension, specific activities of all enzymes measured were significantly increased, levels ranging from 24% above normal for cathepsin C to 351% above normal for N-acetyl-beta-glucosaminidase. Six weeks of normotension following 6 weeks of hypertension resulted in restoration to normal of four of the six enzyme activities; the remaining two enzymes were significantly below normal levels. Combined hypertension and diabetes mellitus showed smooth muscle cell levels of four of the five hydrolases measured to be significantly lower than those present with hypertension alone. In every instance, histochemical studies of aortas showed acid phosphatase and N-acetyl-beta-glucosaminidase activities which corresponded to the biochemical findings. These findings indicate profound and discrete effects of two clinical risk factors on vascular smooth muscle cell lysosomes.
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PMID:Hydrolase activities in the rat aorta. II. Effects of hypertension alone and in combination with diabetes mellitus. 65 43

Dextran blue decreases the activity of lysosomal acid cholesteryl esterase of rat liver at a concentration from 0.25 M to 10 M without altering acid phosphatase, acid beta-galactosidase and beta-glucosidase activities. The dextran blue filled lysosomes with a high degree of purity prepared by centrifugation over the linear sucrose density gradient contained insignificant impurities (up to 19%) of protein from other organelles. The specific activity of acid phosphatase, beta-galactosidase and beta-glucosidase was increased 35-40-fold in this fraction, whereas the activity of acid cholesteryl esterase rose but 14.7-fold. Chromatography on a Sepharose 2B column of the digitonin-digested native and dextran-containing lysosomes attests to the formation of large dextran aggregates with lysosomal matrix proteins. Since aggregation of dextran blue with acid phosphatase, beta-galactosidase and beta-glucosidase does not affect their activities, it is concluded that to bring about hydrolysis of lipoprotein cholesterol esters, it is necessary that cholesteryl esterase be associated with hydrophobic macromolecules. Moreover, dextran blue can be used for simulation cholesterol esters deposition in lysosomes.
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PMID:[Inhibition of liver lysosomal cholesterol esterase activity in rats by dextran blue in vivo and in vitro]. 240 93

Normal arterial foci which take up Evans blue dye (EBD) in vivo are believed to represent atherosclerosis-prone, hemodynamically stressed foci compared to areas which exclude dye. We have used the rabbit EBD model to examine focal aortic hydrolases of blue areas versus white areas, and we report herein significant focal variations of hydrolase activities. Enzymes measured included neutral alpha-glucosidase, N-acetyl-beta-glucosaminidase, alpha-mannosidase, acid alpha-glucosidase, beta-galactosidase, beta-glucuronidase, cathepsin C, and acid cholesteryl esterase (ACE); specific activities were expressed on the basis of tissue DNA. In correlative areas of EBD uptake in normal rabbit aortic arch, ACE activity averaged 17% higher and cathepsin C activity averaged 37% lower than activities of areas free of EBD in the descending thoracic aorta (P less than 0.02). None of the glycosidases studied differed significantly between blue and white aortic areas. These findings indicate that discrete, intrinsic differences of hydrolytic enzyme activities exist in the normal rabbit aorta in areas delineated by in vivo EBD uptake, areas recognized as lesion-prone vs lesion-resistant.
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PMID:Intrinsic focal variations of rabbit aortic hydrolase activities. 276 19

Injection of Triton WR 1339 into Wistar rats caused a marked increase in contents of free and ester-bound cholesterol, triglycerides, phospholipids and free fatty acids in tissues and a decrease in the activity of lecithin: cholesterol acyltransferase in blood. An increase in concentration of cholesterol esters in tissues was due to a decrease in activity of lysosomal cholesteryl esterase in vivo and in vitro and to an increase in non-sedimentable activities of acid phosphatase, beta-galactosidase and cholesteryl esterase. The decrease in proteolytic degradation of cholesterol esters was accompanied by an increase in the activity of tissue cytoplasmic cholesteryl esterase and by a decrease in activity of acyl-CoA: cholesterol O-acyltransferase in liver tissue.
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PMID:[Activity of cholesterol metabolism enzymes and lipid levels in the rat liver, aorta, adrenals and serum after exposure to triton WR 1339]. 372 78

Intraperitoneal administration of chloroquine (50 mg/kg, 7 days) to rats was followed by the increase of cholesterol, its esters, triglycerides and phospholipids levels in tissues, the decrease of lysosomal cholesterol esterase and acyl-koA-cholesterol acyl transferase activity in the liver and the enhancement of the non-sedimentable activity of acid phosphatase and beta-galactosidase. At concentration range of 3.5 to 140 mM the drug inhibited the activity of cholesterol esterase in the rat liver lysosome fraction.
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PMID:[Activity of key enzymes of cholesterol biotransformation and lipid content in the liver, aorta, adrenals and blood of rats exposed to chloroquine]. 375 33

Clone pHICE0.9 was selected from human insulinoma cDNA library by immunoscreening with antibodies against total human insulinoma proteins. This clone contains a 0.9 kb cDNA insert and expresses a fusion protein with beta-galactosidase. Nucleotide sequences of 5'- and 3'-terminal regions of this cDNA insert show that clone pHICE0.9 expresses a protein which is identical to the C-terminal fragment (amino acids 483 to 745) of human pancreatic cholesterol esterase and Homo sapiens bile-acid-salt-stimulated lipase from milk. It is concluded that the protein fragment contains the antigenic determinant of human cholesterol esterase/lipase, and can be used for lipase determination in blood.
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PMID:[Cloning, determination of primary structure, and expression of the C-terminal segment of human cholesterol-esterase/lipase, containing the antigenic determinant of the protein, in Escherichia coli]. 751 66

A human insulinoma cDNA library was constructed in the expression plasmid vector pUEX1. The clone pUEX1Ins12 was selected by means of hybridization with an insulin probe. It codes for full size amino acid sequence preproinsulin. The bacterial strain pUEX3Ins8 producing proinsulin as beta-galactosidase fusion protein was obtained for the use of recombinant protein as an antigen in an ELISA to detect serum antibodies in subjects with IDDM. Recombinant clones containing the middle, N- and C-terminal domains of the GAD65, the major autoantigen in IDDM, were constructed in pVEX1. These clones may become important tools to study the nature of GAD autoreactivity in IDDM. The clone pHICEO.9 was selected from the human insulinoma cDNA library by immunoscreening with total human insulinoma protein antibodies. This clone expresses the C-terminal fragment of human cholesterol esterase/lipase containing its antigenic determinant and can be used for blood lipase determination. Four clones containing cDNA inserts (0.47-1.42 kb) without any significant homologies to the known sequences in the Gene Bank were obtained by means of statistic selection.
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PMID:[Study on structural gene expression in human insulinoma]. 774 51

Hepatic neutral cytosolic cholesteryl ester hydrolase (hncCEH) is a key enzyme in the regulation of hepatic free cholesterol (FC). In examining the effects of over-expression of this enzyme on cholesterol homeostasis, mice were infected with a recombinant adenovirus construct (AdCEH) of the rat hncCEH cDNA driven by the human cytomegalovirus promoter. Cholesteryl esterase and p-nitrophenylcaprylate (PNPC) esterase activities were measured in liver postmitochondrial supernatants at 1, 3, 7, and 11 d after infection with AdCEH or a control virus expressing beta-galactosidase (AdbetaGAL). The PNPC esterase activity of AdCEH mice peaked threefold higher than controls on day 2, declining on subsequent days. In contrast, cholesteryl esterase peaked eightfold higher than controls on day 3, indicating a shift in substrate selectivity of hncCEH. Hepatic FC peaked at 144% of controls, 7 d postinfection. The mRNAs for cholesterol 7alpha-hydroxylase, sterol 27-hydroxylase, and HMG-CoA reductase decreased to 47, 46, and 58% of controls, respectively, on day 7, coinciding with peak FC concentrations. Coinciding with increased cholesteryl esterase activity, hepatic esterified cholesterol dropped precipitously from day 3 onward, to 11% of controls by day 11. Hepatic TAG levels also declined, consistent with the reported TAG lipase activity of hncCEH. These results demonstrate elevation of FC and depletion of cholesteryl esters by over-expression of hncCEH, which were resistant to compensatory responses by other enzymes of cholesterol homeostasis.
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PMID:Over-expression of hepatic neutral cytosolic cholesteryl ester hydrolase in mice increases free cholesterol and reduces expression of HMG-CoAR, CYP27, and CYP7A1. 1582 28


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