Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.26 (invertase)
 4,927 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Lactase and sucrase activities were measured in jejunal biopsies from a group of alcoholic and nonalcoholic men of similar nutritional status, consisting of American blacks, and whites of northern European origin. When measured withing 10 days of alcohol withdrawal, sucrase activity was decreased by 33% in the alcoholics. Lactase activity was less than 1 U per g in 100% of the black and 20% of the white alcholics as compared to 50% of the black and none of the white control subjects. Lactase activity was virtually absent in 45% of the black alcoholics. A second jejunal biopsy after an additional 2-week period of alcohol abstinenece exhibited significant secondary increases in the activities of both disaccharidases. Oral administration of lactose (1 g per kg of body weight) resulted in significantly lower blood glucose concentration and higher incidence of adverse effects in alcoholics, mainly among the blacks. Although data from larger populations are needed to confirm our observations, these findings suggest that chronic alcohol ingestion decreases intestinal disaccharidase activities even in the absence of overt malnutrition. The decrease in enzyme activity produced by alcohol is associated with increased morbidity after lactose administration.
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PMID:Symptomatic intestinal disaccharidase deficiency in alcoholics. 83 22

The effects of carbohydrate intake on jejunal disaccharidases in rats with chronic mannitol-induced, osmotic diarrhea were studied. Weanling rats were force-fed 5 ml/100 g of body weight of water of 20% mannitol (w/v 1300 mOsm) daily for up to 14 days. Diets containing 70% of either starch, sucrose, glucose, or 20% lactose with 50% starch were fed ad libitum. Mannitol-fed rats had increased water intake and diarrhea. They gained weight, but less than controls. The levels of intestinal disaccharidases in mannitol-fed rats were related to dietary carbohydrate intake. Seven days of mannitol treatment led to lactase and sucrase deficiencies in rats fed starch whereas jejunal maltase and alkaline phosphatase were unchanged. Deficiencies in lactase and maltase but not in sucrase were induced when rats were fed a sucrose diet, while a decrease only in sucrase occurred in rats fed a lactose-starch diet. Rats with mannitol-induced diarrhea fed a glucose diet had reduced levels of all disaccharidases. The changes in intestinal disaccharidases were not associated with alterations in the number of epithelial cells or ultrastructural abnormalities. 3H-thymidine incorporation into DNA following 7 days of mannitol treatment was similar to water-fed controls. Absorptive epithelial cells were not damaged and the microvilli were normal in height and appearance. These data suggest that the levels of specific disaccharidases show and enhanced dependence upon the corresponding dietary substrates during diarrhea induced by an osmotic load.
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PMID:Interaction between dietary carbohydrates and intestinal disaccharidases in experimental diarrhea. 85 Oct 74

Twenty-eight Sioux and 29 Saluteaux Indians from a southern and an isolated northern Manitoban community were screened for lactose malabsorption; 55 were also screened for sucrose tolerance. Sixty percent of the subjects were lactose malabsorbers; the incidence increased with age. Lactase deficiency appeared, on the average, between 8 and 15 years of age. About 45% of the subjects were lactose intolerant. Malabsorbers who did not regularly drink milk had the highest symptom scores. The northern subjects consumed significantly more lactose and sucrose than the southern subjects. Two Sioux children were sucrose malabsorbers. It was hypothesized that the significantly greater sucrose consumption by the Saulteaux subjects were responsible for their markedly higher blood glucose curve following the sucrose tolerance tests. Dietary sucrose increases jejunal sucrase activity and the intestinal transport of glucose and fructose. Three of eight children less than 4 years were lactose malabsorbers; hence, medical personnel treating noninjective diarrhea in Indian children should examine for lactase deficiency. It was recommended that vitamin D fortified milk supplements to Indian school children be continued and that the milk be treated so as to reduce abdominal symptoms in the intolerant individuals.
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PMID:Disaccharide consumption and malabsorption in Canadian Indians. 85 12

The separation by polyacrylamide gel electrophoresis and subsequent enzymatic analysis of the components of the guinea pig intestinal brush border membrane revealed the presence of three enzyme complexes: maltase-glucoamylase, maltase-sucrase-glucoamylase and maltase-sucrase. Additional bands possessing lactase, trehalase and alkaline phosphatase activity were identified but no phlorizin hydrolase or palatinase was detectable. After exposure to strong dissociating conditions the bands possessing enzymatic activity were either absent or greatly reduced in intensity.
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PMID:Glycosidases of the guinea pig brush border membrane. 86 Dec 25

Small intestinal morphologic and biochemical changes were studied following jejuno-ileal bypass for obesity after body weight stabilization had occurred. Four patients underwent biopsy of in-continuity and bypassed jejunal and ileal segments of the small intestine 11 to 22 months after the bypass operation. Microscopically, marked mucosal villus hypertrophy of the in-continuity bowel was observed, especially in the ileum. Bypassed jejunal mucosa underwent atrophy compared with pre-bypass jejunum, whereas bypassed ileum appeared similar microscopically to pre-bypass ileum. The specific activities of mucosal disaccharidase enzymes (maltase, sucrase, lactase and trehalase) in units per mg protein remained similar to pre-bypass levels in segments of the in-continuity jejunum and the bypassed jejunum and ileum. On the other hand, elevated mucosal disaccharidase levels were measured in biopsy specimens of the in-continuity ileum. Total enzyme activity per unit length of intestine, however, was estimated to be elevated in both in-continuity jejunum and ileum secondary to mucosal villus hypertrophy. These data indicate that following small bowel bypass: (1) the in-continuity ileum undergoes greater biochemical and morphologic adaptation than the jejunum; and (2) intraluminal nutrients and chyme appear to be essential to maximal intestinal adaptation.
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PMID:Gastrointestinal adaptation following small bowel bypass for obesity. 87 Dec 20

Chronic application (20 days) of glucagon in pharmacological doses induces mucosal transformation of the hyperregenerative type in the small intestine of the rat. This transformation is characterized by decreased villi, and increased crypt length. The morphological changes are accompanied by a reduction in glucose absorption in vivo as well as by decreased activities of lactase, sucrase and maltase. The findings demonstrate that hyperglucagonemia is not the cause for hyperplastic mucosal transformation, which is found in the experimental diabetes in the rat.
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PMID:[Functional and morphological studies on intestinal mucosa of the rat under chronic glucagon application (author's transl)]. 88 15

Intestinal mucosa and pancreas from purebred Beagle dogs were assayed for carbohydrase activity, using several methods of tissue treatment. The enzymes found and studied were alpha-amylase, sucrase, lactase, amyloglucosidase, cellobiase, maltase, and isomaltase. Experiments using polyacrylamide gel columns and heat inactivation showed the presence of an isozyme of maltase which degrades isomaltose. This activity had not been previously demonstrated in dogs. An optimal standard procedure is presented for the preparation and assay of canine digestive enzymes. A statistical analysis of variance of the results showed that the variance was primarily associated with differences among dogs and not by variance within the procedure. When the different extraction procedures were used, results indicated that the level of enzymes detected differed with the method of treatment.
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PMID:Detection and definition of canine intestinal carbohydrases, using a standardized method. 88 14

Rats with chronic uremia following five-sixths nephrectomy showed a significant fall in the sucrase and maltase activities in the small intestinal mucosa, the lactase and cellobiase activities in contrast remained uninfluenced. The activity of the L-leucyl-L-proline and L-methionyl-L-proline dipeptidases in the small intestinal mucosa was significantly increased, while the activities of seven other dipeptidases studied were unaffected. The mucosal protein and DNA content likewise remained unchanged. Occasional slight alterations of the mucosa were the only finding at histology.
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PMID:Activities of intestinal enzymes in experimental chronic renal insufficiency. 88 89

Follow-up studies on 36 children, in whom celiac disease (gluten-sensitive enteropathy) was established by gluten challenge, were carried out after management on gluten-free diets for a mean of six years. Evaluations included measurement of height and weight, which for the group approximated normal distributions, and histologic examination of the duodenal or jejunal mucosa. Mucosal morphology was regarded as normal in 16, and there were minimal changes in 20. Epithelial cell height was within the normal range in all the children. Interepithelial lymphocytes were within normal range in the majority and lymphoid cells in the lamina propria were not different from those in control subjects. Mucosal lactase was significantly lower in patients than in control subjects in the duodenum and the jejunum, whereas sucrase and alkaline phosphatase values were significantly lower in the jejunum but not in the duodenum. Low content of mucosal lactase and increased numbers of interepithelial lymphocytes may be sensitive indicators of persisting ingestion of gluten in mucosa that is otherwise normal or approximately so in appearance.
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PMID:Mucosal recovery in treated childhood celiac disease (gluten-sensitive enteropathy). 95 66

On the basis of comparative determinations of the activities of dipeptidases and disaccharidases of the mucous membrane of the small intestine (proximal jejunum) clear correspondences between the morphological findings and the biochemical parameters were the result. L-alanyl-L-prolin-dipeptidase and glycyl-L-valin-dipeptidase as well as lactase, saccharase, maltase and trehalase were determined in altogether 45 children with various malabsorption syndromes of different age in different stages of disease. Diminutions of the activity of the dipeptidases were to be proved analogously to maltase, saccharase and lactase, too, in most cases of subtotal or total villous atrophy. From the results conclusions may be derived to the restricted ability of protein absorption in chronic disease of the small intestine.
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PMID:[L-alanyl-L-proline-dipeptidase and glycyl-L-valine-depeptidase in malabsorption syndrome]. 96 Sep 1


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