Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.108 (lactase)
 2,133 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method for measuring brush border membrane enzymes from small intestinal biopsies by crossed immunoelectrophoresis is presented. The use of a brush border specific antiserum made isolation of the brush border membrane before analysis unnecessary. This prevented loss of material which, together with inactivation of enzymes, was a limiting factor in previous studies of brush border enzymes from peroral biopsies. In 58 biopsies from patients without gastrointestinal disorders a close correlation between antigenic activity and corresponding enzymatic activity was shown for the following enzymes: sucrase-isomaltase (EC 3.2.1.48-EC 3.2.1.10), lactase-phlorizin hydrolase (EC 3.2.1.23-EC 3.2.1.62), microvillus aminopeptidase (microsomal, EC 3.4.11.2) and dipeptidyl peptidase IV (EC 3.4.14.X). The immunoelectrophoretic patterns of intestinal mucosa near the ligament of Treitz, and in jejunum and ileum were established. The method presented is thought to be of value in further studies of the molecular basis of brush border diseases.
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PMID:Immunoelectrophoretic studies on human small intestinal brush border proteins. A quantitative study of brush border enzymes from single small intestinal biopsies. 10 36

The human small intestinal brush border proteins were studied qualitatively by crossed immunoelectrophoresis. Brush border membranes were purified from human jejunum and the proteins released by Triton X-100. Rabbits were immunized with the released proteins and by using a double layer immunofluorescence technique the obtained antisera were shown to be specific against the brush border proteins. The precipitates obtained in crossed immunoelectrophoresis were identified by enzymatic staining techniques. Sucrase (EC 3.2.1.48), isomaltase EC 3.2.1.10), maltase (EC 3.2.1.20), phloretin-glucosidase (EC 3.2.1.62), lactase (EC3.2.1.23), microvillus aminopeptidase (aminopeptidase (microsomal), EC 3.4.11.2), dipeptidyl peptidase IV (EC 3.4.14.X), and alkaline phosphatase (EC 3.1.3.1) were identified while asparate aminopeptidase (EC 3.4.11.7), gamma-glutamyl transferase (EC 2.3.2.2) and trehalase (EC 3.2.1.28) could not be visualized. This work demonstrates that cross immunoelectrophoresis can be used in the study of human small intestinal brush border proteins.
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PMID:Immunoelectrophoretic studies on human small intestinal brush border proteins. A qualitative study of the protein composition. 36 59

Oral administration of embelin (75 mg/kg per day, daily for 15 and 30 days) to male rats caused significant elevation in the uptake of D-glucose, L-alanine, L-leucine and calcium in small intestinal segments. Embelin also produced significant increases in intestinal brush border membrane-associated enzymes (sucrase, lactase, maltase, alkaline phosphatase and leucine aminopeptidase) in both intestinal homogenates and partially purified brush border membrane preparations. Significant increases were also noted for microsomal glucose-6-phosphatase and cytosolic lactate dehydrogenase. Increase in brush border membrane-associated total lipids, phospholipids, cholesterol, triacylglycerol, unesterified fatty acids and ganglioside sialic acid were seen but not in the cholesterol/phospholipid molar ratio. All these changes returned to control or near control levels following withdrawal of the drug.
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PMID:Effects of embelin, a male antifertility agent, on absorptive and digestive functions of rat intestine. 192 15

Administration of Embelin, an experimental antifertility agent, to male rats (20 mg/kg body wt/day, daily for 15 and 30 days), caused an elevation in the uptake of D-glucose, L-alanine, L-leucine, and calcium in the small intestinal segments. An increase was also noted in the intestinal brush border membrane (BBM)-associated enzymes, sucrase, lactase, maltase, alkaline phosphatase, and leucine aminopeptidase in both the intestinal homogenates and partially purified BBM preparations, particularly after 30-day administration of the drug. Embelin treatment also caused a significant increase in the microsomal glucose-6-phosphatase and the cytosolic enzyme, lactate dehydrogenase. In the Embelin-treated animals BBM-associated total lipids, phospholipids, cholesterol, triacylglycerol, unesterified fatty acids, ganglioside-sialic acids as well as the cholesterol/phospholipids molar ratio showed a considerable increase. All these changes in the Embelin-treated animals were restored back to the normal or near normal biochemical makeup when the drug therapy was withdrawn and the animals were allowed to recover for another 15 and 30 days, respectively.
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PMID:Changes in glucose/amino acid/calcium uptake and brush-border membrane-associated enzymes in rat small intestine after the administration of embelin (plant benzoquinone), an antifertility agent. 211 47

To further document the effect of insulin on intestinal maturation, suckling rats were treated either with exogenous insulin (12.5 mU.g body wt, intraperitoneally, twice daily) or with saline from d 8 to 12 postpartum. Sucrase activity in brush border membrane extracts was precociously induced by insulin, whereas the activities of other brush border membrane enzymes (maltase, aminopeptidase, and neutral lactase) were enhanced (+ 30 to + 131%, p less than 0.01 versus controls). The lysosomal enzyme, N-acetyl-beta-glucosaminidase, which normally declines at weaning was significantly (p less than 0.025) decreased in both villus (-51%) and crypt cells (-57%) isolated from the jejunum of insulin-treated rats. The microsomal enzyme, sulfatase C, and the cytosolic enzyme, lactate dehydrogenase, were also sensitive to insulin with decreases in activity ranging from -37 to -63% (p less than 0.05) compared to saline-treated control rats. Insulin at doses of 0.5 or 12.5 mU did not influence plasma total corticosterone levels, which were about 9-fold lower in suckling than in 25-d-old weaned rats. In weaned rats (from d 25 to 32) insulin treatment (12.5 mU) failed to influence the activity of brush border membrane hydrolases or of lysosomal, microsomal, and cytosolic enzymes. The synthesis rate of mature sucrase-isomaltase, measured in weaned rats (32 d) by the incorporation of 14C-leucine into the enzyme precursor protein, was equivalent in both groups. These data demonstrate that the immature enterocyte of the suckling rat is responsive to insulin, whereas the mature enterocyte of the weaned rat is unresponsive.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hormonal regulation of the rat small intestine: responsiveness of villus and crypt cells to insulin during the suckling period and unresponsiveness after weaning. 217 34

Some diets exert a considerable influence on porphyrin metabolism and induction of microsomal liver enzymes in experimental porphyria induced by hexachlorobenzene (HCB). As HCB and its metabolites come into direct contact with intestinal mucosa, this study investigated the changes in the activities of intestinal disaccharidases and gamma-glutamyl transferase in a model of HCB-induced porphyria. The effects of different diets on enzymatic activities during HCB intoxication were also studied. HCB was administered by gastric tube at 3.5 mmol/kg body weight daily for 90 and 61 days. HCB intoxication strongly diminished the activities of intestinal lactase, maltase, sucrase, cellobiase and trechalase. Carbohydrate diets (with 78 weight % glucose or starch), given simultaneously with HCB treatment, exerted a protective effect on disaccharidase activities. These regimens maintained cellobiase and trechalase within the normal levels and even increased maltase. High-fat/high-protein diets (with 30% either butter or sunflower oil and 31% casein) aggravated the decrease of all disaccharidases. In contrast with the decrease in disaccharidase activity, intestinal gamma-glutamyl transferase was increased, suggesting multiple mechanisms for the action of HCB intoxication on the intestinal enzyme system. Diet had a pronounced modifying effect.
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PMID:Changes in some intestinal enzyme activities in experimental hexachlorobenzene-induced porphyria and modifying effects of diet. 288 67

A technique for the isolation of intact brush borders from rabbit renal cortex was evaluated. The procedure was monitored by phase and electron microscopy and marker enzymes, i.e. ATP:NMN adenylyl transferase, nuclear; cytochrome oxidase, mitochondrial; beta-glucuronidase, lysosomal; and glucose-6-Pase, microsomal; and indicated an essentially pure preparation of brush borders. The disaccharidase, trehalase, previously reported in renal tubules, was localized uniquely in brush borders. Maltase was also found; the specific activities of the two enzymes in the brush borders were increased 10- to 20-fold. Other disaccharidases, such as sucrase, isomaltase, lactase, and cellobiase, were absent. It is suggested that trehalase and maltase are appropriate candidates for marker enzymes of the renal brush border. Isolated brush borders possessed a ouabain-sensitive (Na(+) + K(+)) ATPase, an oligomycin-insensitive Mg(++) ATPase, and a Ca(++)-activated ATPase. Alkaline phosphatases, dephosphorylating beta-glycero-P, and trehalose-6-P were also present. The specific activities of these enzymes were increased three-to-five fold in the brush-border preparations; however, activities were found in other subcellular fractions of the renal cortex. Hexokinase, although evident in the isolated brush border, was found prominently associated with other membranous fractions. Phosphoglucomutase and UDPG pyrophosphorylase were localized in the soluble fraction of the renal cortex.
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PMID:Isolation and biochemical characterization of brush borders from rabbit kidney. 425 Jun 12

The amounts of lactase (EC 3.2.1.23), sucrase (EC 3.2.1.48), maltase (EC 3.2.1.20), microvillus aminopeptidase (microsomal EC3.4.11.2), and dipeptidyl peptidase IV (EC 3.4.14.X) in biopsies from proximal jejunum and distal ileum were studied by quantitative crossed immunoelectrophoresis and enzymatic assays in obese patients one and six months after jejunoileal bypass operation and compared with peroperative levels. They were related to DNA and protein content. The protein/DNA ratio fell 28-43% postoperatively. Except for ileal lactase and sucrase all enzymes showed decreased levels when expressed per mg protein and an even more pronounced decrease when related to DNA. Lactase and sucrase levels in ileum were increased or unchanged. A constant correlation between the amount of immunoreactive enzyme protein and enzymatic activity was shown for all enzymes except maltase. The results suggest that the bypass operation is followed by an increased amount of enterocytes devoid of or low in enzymatic activity and protein content. The amounts of lactase and sucrase in ileum are increased in relation to the other enzymes. No immunoreactive enzymes with zero or depressed activity were detected.
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PMID:Immunoelectrophoretic studies on human small intestinal brush border proteins: cellular alterations in the levels of brush border enzymes after jejunoileal bypass operation. 742 30

The thyroid is one of the metabolism regulating glands. Its function is to determine the amount of calories that the body has to burn to maintain normal weight. Thyroiditides are inflammatory processes that mainly result in autoimmune diseases. We have conducted the present study in order to have a clear picture of both autoimmune status and the control of body weight. We have evaluated the amount of either thyroid hormones, or antithyroid, or anti-microsomal, or anti-peroxidase antibodies (Abs) in patients with high amounts of Abs. In a diet devoid of carbohydrates (bread, pasta, fruit, and rice), free from goitrogenic food, and based on body mass index, the distribution of body mass and intracellular and extracellular water conducted for 3 weeks gives the following results: patients treated as above showed a significant reduction of antithyroid (-40%, P<0.013), anti-microsomal (-57%, P<0.003), and anti-peroxidase (-44%, P<0,029) Abs. Untreated patients had a significant increase in antithyroid (+9%, P<0.017) and anti-microsomal (+30%, P<0.028) Abs. Even the level of anti-peroxidase Abs increased without reaching statistical significance (+16%, P>0064). With regard to the body parameters measured in patients who followed this diet, reduction in body weight (-5%, P<0.000) and body mass index (-4%, P<0.000) were observed. Since 83% of patients with high levels of autoantibodies are breath test positive to lactase with a lactase deficit higher than 50%, this fact led us to hypothesize a correlation with carbohydrate-responsive element-binding protein and therefore a possible role of carbohydrate metabolism in the development and maintenance of autoimmune thyroiditis associated with body weight increase and slower basic metabolism.
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PMID:Effects of low-carbohydrate diet therapy in overweight subjects with autoimmune thyroiditis: possible synergism with ChREBP. 2769 91