Disaccharidase deficiency

2020 ◽  
pp. 2902-2909
Author(s):  
Timothy M. Cox

Disaccharidases are abundant enzymes expressed on the microvillous membrane of the small intestine: apart from free glucose and fructose, disaccharidases are required for the complete assimilation of nearly all carbohydrate present in food and drinks. The enzymes cleave disaccharides such as sucrose, maltose, and lactose, as well as dextrins derived from starch, into their component monosaccharides. Their activity is reduced in hereditary conditions or in generalized intestinal diseases. Disaccharidase deficiency causes dietary intolerance of carbohydrate induced by the fermentation of undigested sugars in the distal small intestine and colon. Abdominal symptoms are usually noticed within an hour of the ingestion of foods containing the offending sugars. By far the most common symptomatic disaccharidase deficiency is lactose intolerance. Lactase activity is high in healthy infants when milk is the principal food, but in most humans the activity declines after weaning and remains low (lactase nonpersistence), which greatly reduces the capacity to break down lactose. In contrast, those inheriting a Mendelian dominant trait that leads to sustained high intestinal lactase expression throughout life (lactase persistence) digest and tolerate large quantities. The distribution of lactase activity in adult populations is subject to great variation. Intestinal lactase phenotypes can be identified by assay of mucosal biopsy samples or appropriate sugar tolerance tests, as can other (much rarer) genetically determined disaccharidase variants. The most convenient diagnostic screen involves hydrogen breath testing after oral loading. Disaccharide intolerance is readily treated by institution of a strict exclusion diet; oral enzymatic supplementation may benefit patients with severe enzymatic deficiency. Innovative and early phase clinical trials suggest that modulation of the host intestinal microbiome with a pure short-chain galacto-oligosaccharide may be beneficial in symptom control and in favouring the outgrowth of lactose-fermenting flora.

Nutrients ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1787 ◽  
Author(s):  
Annick Alleleyn ◽  
Mark van Avesaat ◽  
Dina Ripken ◽  
Sinéad Bleiel ◽  
Daniel Keszthelyi ◽  
...  

Activation of the intestinal brake by infusing nutrients into the distal small intestine with catheters inhibits food intake and enhances satiety. Encapsulation of macronutrients, which protects against digestion in the proximal gastrointestinal tract, can be a non-invasive alternative to activate this brake. In this study, we investigate the effect of oral ingestion of an encapsulated casein and sucrose mixture (active) targeting the distal small intestine versus a control product designed to be released in the stomach on food intake, satiety, and plasma glucose concentrations. Fifty-nine volunteers received the active and control product on two separate test days. Food intake was determined during an ad libitum meal 90 min after ingestion of the test product. Visual analogue scale scores for satiety and blood samples for glucose analysis were collected at regular intervals. Ingestion of the active product decreased food intake compared to the control product (655 kcal compared with 699 kcal, respectively, p < 0.05). The area under the curve (AUC) for hunger was decreased (p < 0.05) and AUC for satiety was increased (p < 0.01) after ingestion of the active product compared to the control product. Ingestion of an encapsulated protein-carbohydrate mixture resulted in inhibition of food intake compared to a non-encapsulated control product.


1993 ◽  
Vol 264 (6) ◽  
pp. G1169-G1176 ◽  
Author(s):  
E. B. Rand ◽  
A. M. Depaoli ◽  
N. O. Davidson ◽  
G. I. Bell ◽  
C. F. Burant

cDNA clones encoding rat GLUT5-small intestinal facilitative hexose transporter were isolated from a jejunum library by cross-hybridization with a human GLUT5 cDNA probe. The cDNA sequence indicates that rat GLUT5 is composed of 502 amino acids and has 81.5% amino acid identity and 87.3% similarity with the sequence of human GLUT5. Expression of synthetic rat GLUT5 mRNA in Xenopus oocytes showed that rat GLUT5 was able to mediate the uptake of fructose and, to a lesser extent, of glucose. RNA blotting studies showed that GLUT5 mRNA was present in rat small intestine, kidney, and brain. Although GLUT5 mRNA is expressed in human testis, adipose tissue, and skeletal muscle, it could not be detected by RNA blotting in these rat tissues. Developmental studies showed low levels of GLUT5 mRNA in rat small intestine and kidney during the prenatal period with a rapid induction of GLUT5 expression occurring postnatally. In situ hybridization studies of GLUT5 mRNA expression in the small intestine revealed differential expression along the crypt-villus axis with the highest levels of mRNA being in the midvillus region. In addition, there was quantitatively more GLUT5 mRNA detected in the proximal as opposed to the distal small intestine.


1990 ◽  
Vol 259 (3) ◽  
pp. G355-G363 ◽  
Author(s):  
M. F. Otterson ◽  
S. K. Sarna

We studied the small intestinal motor effects of oral and intravenous (iv) erythromycin in 10 conscious dogs. After control recordings with placebo, oral or iv erythromycin was given at 40% of the migrating motor complex (MMC) cycle. Recordings were made after administration until normal contractile activity had returned or 12 h postdrug administration. Low doses initiated a premature MMC. High doses, however, prolonged the MMC cycle length. Erythromycin reduced the MMC propagation velocity at all doses. Both oral and iv erythromycin induced amyogenesia. During this pattern, electrical control activity was obliterated in the proximal and destabilized in the distal small intestine. Erythromycin also increased the incidence of retrograde giant contractions (RGCs) and vomiting. These effects occurred within the first 2 h after oral and within the first 30 min after iv administration. The incidence of giant migrating contractions (GMCs) increased significantly from 5 to 12 h but not from 0 to 5 h after administration. The distance of origination of GMCs from the ileocolonic junction was significantly increased from 5 to 12 h. The amplitude ratio, duration, and velocity of migration of GMCs induced after erythromycin were similar to control values. Clusters of coordinated antral and duodenal contractions also occurred early after administration. Our findings suggest that erythromycin has multiple motor effects on the stomach and small intestine. Diarrhea, abdominal cramping, and vomiting associated with erythromycin may be related to increased incidence of GMCs and RGCs. Erythromycin has a biphasic effect on MMC cycle length, initiating premature MMCs at low doses and prolonging their cycle length at higher doses.(ABSTRACT TRUNCATED AT 250 WORDS)


1995 ◽  
Vol 268 (6) ◽  
pp. G879-G888 ◽  
Author(s):  
C. E. Kight ◽  
S. E. Fleming

The influence of glutamine on glucose oxidation was assessed in epithelial cells isolated from the mucosa of the proximal, mid-, and distal small intestine of young, fed, male rats. Glucose oxidation declined along the length of the small intestine, with values from the mid- and distal segments representing approximately 55% and 40%, respectively, of the value from the proximal segment. A gradient along the small intestine was noted also in the influence of glutamine on glucose oxidation: glutamine suppressed glucose oxidation approximately 60% in the proximal small intestine, 39% in the mid-intestine, and 31% in the distal small intestine. Glutamine suppressed the oxidation of glucose carbon that entered the tricarboxylic acid (TCA) cycle; this was determined using CO2 ratios derived from acetate and glucose isotopes. In cells from the proximal segment, the probability that carbon entering the cycle would complete one full turn was reduced by glutamine from 0.77 to 0.28. The entry of glucose-derived pyruvate into the TCA cycle did not appear to be influenced by the presence of glutamine, however. Glutamine had no influence on the proportion of glucose metabolism that occurred via the pentose phosphate pathway (which averaged 5% or less), but reduced flux of carbon through pyruvate carboxylase relative to flux through pyruvate dehydrogenase from 40% to 9% in cells from the proximal segment. These data suggest that, in the presence of glutamine, the fate of pyruvate carbon (derived from glucose or elsewhere) entering the TCA cycle is altered from that of oxidation to anaplerosis and subsequent efflux of TCA cycle intermediates into newly synthesized compounds.


1963 ◽  
Vol 205 (1) ◽  
pp. 107-111 ◽  
Author(s):  
Harold E. Harrison ◽  
Helen C. Harrison

Everted loops of rat small intestine were incubated in media varying in their concentrations of sodium and potassium. Reduction of sodium concentration was effected by substitution of choline chloride in equimolar amounts for sodium chloride in the saline-bicarbonate buffer. Concentrative transport of glucose, l-tyrosine, inorganic phosphate, and calcium was measured by determination of the final ratio of the concentrations of the solute in serosal and mucosal fluids, and the increment of the solute in serosal fluid during incubation. Ca45 was used as an indicator of calcium distribution. The glucose, l-tyrosine, and inorganic phosphate transport systems require sodium, and at a submaximal concentration of sodium an increased concentration of potassium is inhibitory. The calcium transport system does not require sodium and in loops from the distal small intestine calcium transport is enhanced by reduction of sodium concentration in the medium. It is postulated that there is a common sodium-requiring system which is necessary for the linkage of metabolic energy to glucose, amino acid, and inorganic phosphate transport.


1997 ◽  
Vol 273 (4) ◽  
pp. G968-G978 ◽  
Author(s):  
Sharon E. Fleming ◽  
Kirsten L. Zambell ◽  
Mark D. Fitch

The objectives of this study were to establish a reliable method for quantifying glycolytic flux in intestinal epithelial cells, to determine the proportion of energy provided to small intestine epithelial cells by glucose vs. glutamine, and to determine whether there was an energetic advantage to having both substrates present simultaneously. There was substantial retention of 3H in alanine and lactate when [2-3H]glucose was used as tracer for quantifying glycolysis, and the magnitude of the3H retention was influenced by the presence of other substrates and metabolites. Detritiation was at least 99% complete, however, when [3-3H]glucose was used as tracer in this system and the tritium was recovered as3H2O. Glycolytic flux was six- to sevenfold higher in cells of the proximal than distal small intestine but was not significantly different for young adult (4 mo) vs. aged adult (24 mo) rats. Net ATP production from exogenous substrates was higher when both glucose and glutamine were present simultaneously than when either substrate was present alone, and glucose was calculated to provide 50–60% of the net ATP produced from these two substrates. Most of the energy produced from glucose was produced via the anaerobic metabolic pathways (78% for glucose alone, 95% with glucose and glutamine). Net energy production was calculated to be 10% lower in cells from aged animals than in those from young animals, since CO2 production from these major substrates was lower in cells from aged animals.


2021 ◽  
Vol 11 ◽  
Author(s):  
Heather M. Kahalehili ◽  
Nolan K. Newman ◽  
Jamie M. Pennington ◽  
Siva K. Kolluri ◽  
Nancy I. Kerkvliet ◽  
...  

The diet represents one environmental risk factor controlling the progression of type 1 diabetes (T1D) in genetically susceptible individuals. Consequently, understanding which specific nutritional components promote or prevent the development of disease could be used to make dietary recommendations in prediabetic individuals. In the current study, we hypothesized that the immunoregulatory phytochemcial, indole-3-carbinol (I3C) which is found in cruciferous vegetables, will regulate the progression of T1D in nonobese diabetic (NOD) mice. During digestion, I3C is metabolized into ligands for the aryl hydrocarbon receptor (AhR), a transcription factor that when systemically activated prevents T1D. In NOD mice, an I3C-supplemented diet led to strong AhR activation in the small intestine but minimal systemic AhR activity. In the absence of this systemic response, the dietary intervention led to exacerbated insulitis. Consistent with the compartmentalization of AhR activation, dietary I3C did not alter T helper cell differentiation in the spleen or pancreatic draining lymph nodes. Instead, dietary I3C increased the percentage of CD4+RORγt+Foxp3- (Th17 cells) in the lamina propria, intraepithelial layer, and Peyer’s patches of the small intestine. The immune modulation in the gut was accompanied by alterations to the intestinal microbiome, with changes in bacterial communities observed within one week of I3C supplementation. A transkingdom network was generated to predict host-microbe interactions that were influenced by dietary I3C. Within the phylum Firmicutes, several genera (Intestinimonas, Ruminiclostridium 9, and unclassified Lachnospiraceae) were negatively regulated by I3C. Using AhR knockout mice, we validated that Intestinimonas is negatively regulated by AhR. I3C-mediated microbial dysbiosis was linked to increases in CD25high Th17 cells. Collectively, these data demonstrate that site of AhR activation and subsequent interactions with the host microbiome are important considerations in developing AhR-targeted interventions for T1D.


PEDIATRICS ◽  
1971 ◽  
Vol 47 (1) ◽  
pp. 65-72
Author(s):  
L. K. McNeill ◽  
J. R. Hamilton

We assessed intestinal structure, mucosal epithelial kinetics, and disaccharidase activities after fasting. Rats fasted for up to 120 hours were compared with control rats fed ad libitum. All rats had free access to water and all were prevented from ingesting their own stools. Body weight, small intestinal weight and mucosal protein, and maltase and sucrase activity of the total small intestine decreased in fasted rats. Lactase activity did not decrease. Specific activity of lactase actually increased in the jejunum. Assessed after a 96-hour fast, jejunal villi were shortened with less epithelial cells along their length and the rate of migration of those cells along the villi was diminished in the fasted rats compared with control rats. We attribute the decreased total intestinal sucrase and maltase activities to a loss of total epithelial cell mass in the small bowel. An abnormality in the cells of the progenitor zone of the crypts is suggested by the decreased migration rate of mucosal epithelial cells in fasting rats. These factors do not explain our observations completely since lactase activity did not diminish. We postulate that the activity of the "acid" β-galactosidase located in the cytoplasm or lysosomes of the epithelial cells was stimulated by fasting. Our observations are relevant to clinical pediatrics. Undernutrition and fasting my be associated with many childhood diseases and with treatment of disease. In assessing clinical data and advising treatment, the pediatrician should be aware of the potentially harmful effects of starvation on intestinal structure and function.


2020 ◽  
pp. 1-6
Author(s):  
Vladimir Leonidovich Martynov ◽  
◽  
Natalia Vladimirovna Kazarina ◽  

Objective: To determine the syndrome of excessive bacterial growth in the small intestine (SIBO) in patients with insufficiency of the bauhinia valve (NBZ) and after its surgical correction. Methods of examination: Patients of the studied groups were examined using direct and indirect methods of diagnosis of SIBO. Bacteriological examination of ileal aspirate and other surgical material was performed. All patients underwent a hydrogen respiratory test with a load of lactulose and performed a qualitative reaction of urine to indican. Characteristics of the material: 50 patients were examined, of which 30 were included in the main group, who underwent surgical correction of NBZ - Bauginoplasty; 20 patients are included in the control group in which the ileocecal valve is consistent. Patients of the main group were examined before surgery and on the 7th and 45th day after Bauhinoplasty. Main results: All patients of the main group had SIBS of varying severity, in 80% of patients SIBS was localized in the distal small intestine. Patients with normal function of ileocecal valve syndrome of excessive bacterial growth did not suffer. Intraoperatively, 76% of patients showed signs of mesenteric mesentery of the small intestine, and the fact of bacterial translocation in SIBO was also confirmed. After 7 days after surgical correction of the Bauhinia valve, the normalization of peak and background excretion of hydrogen was observed in 37% of patients. For 45 days in all patients the hydrogen curve corresponded to the norm. Conclusions: the deficiency of the bauhinia valve is obligately accompanied by the syndrome of excessive bacterial growth in the small intestine, surgical correction is an effective method for correcting the syndrome of excessive bacterial growth in patients with NBD.


2020 ◽  
Vol 44 (9) ◽  
pp. 1859-1871 ◽  
Author(s):  
Ida M. Modvig ◽  
Daniel B. Andersen ◽  
Kaare V. Grunddal ◽  
Rune E. Kuhre ◽  
Christoffer Martinussen ◽  
...  

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