Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024523 (malabsorption)
 7,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Juvenile rats fed a diet containing 1% lead acetate for 7 weeks, in addition to an impaired growth rate and renal function derangements, suffered malabsorption of glucose and certain amino acids, as assessed by an in vivo perfusion technique. The reduction in glucose absorption ranged between 10% and 31% when the carbohydrate was pumped in concentrations of 2-80 mM. This alteration was compatible with a noncompetitive type of transport inhibition. The intestinal absorption of glycine, lysine, and phenylalanine were, respectively, decreased 22, 18, and 15% when these amino acids were present at 1 mM levels. Sodium transport was severely reduced (57.6 +/- 17.9 (SEM) vs. 124.2 +/- 17.4 muEq/min-cm) and intestinal mucosa (Na+-K+)-ATPase was concomitantly lower in the lead-intoxicated rats (186.4 +/- 19.0 vs 268.4 +/- 29.8 nmol P/min-mg protein). However, this enzyme was not altered in liver and kidney. Furthermore, intestinal mucosa fructose-1,6-diphosphatase, succinic dehydrogenase, pyruvate kinase, and tryptophan hydroxylase were not different in experimental and control animals. These studies substantiate the presence of functional and biochemical abnormalities in the intestinal mucosa of young rats when fed substantial amounts of a soluble lead salt. It is, therefore, reasonable to accept the possibility that physiologic damage occurs in tissues directly subjected to high and persistent levels of a toxic agents, as it occurs in other organs, underscoring the parallelism between transport mechanisms at the renal and intestinal levels.
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PMID:Experimental lead poisoning and intestinal transport of glucose, amino acids, and sodium. 13 38

A 9-year-old girl with hereditary dibasicaminoaciduria has been studied for three years. Initially, clinical features were: growth failure; anorexia and aversion to protein, spontaneous daily protein intake averaging only 10 gm; fasting and postprandial venous hyperammonemia; subnormal plasma concentrations of lysine, arginine, ornithine, and citrulline, with generalized hypermonobasicaminoacidemia; abnormally high renal clearances of lysine, arginine, and ornithine; and intestinal malabsorption of lysine and arginine. Intestinal absorption of citrulline, a precursor of arginine and ornithine, was normal. The patient was observed during four sequential 6-month periods as follows: no treatment (Period I); dietary supplement of arginine and lysine (Period II); dietary supplement of citrulline and lysine (Period III); no treatment (Period IV). During Periods II and III growth rate increased 3- to 4-fold, spontaneous protein intake increased 2- to 3-fold, and abnormalities in blood NH3 and the plasma aminogram were partially corrected. In most respects the citrulline plus lysine supplement was more beneficial than that of arginine plus lysine.
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PMID:Hyperdibasicaminoaciduria, hyperammonemia, and growth retardation: Treatment with arginine, lysine, and citrulline. 118 37

Jejunal biopsies were obtained from 37 children with cystic fibrosis, 16 with gluten-induced enteropathy, and 18 control subjects for the following studies: (1) disaccharidase activity, (2) L-ALA-L-Phe hydrolase activity, and (3) intestinal uptake of three 14C-labeled amino acids. Values were significantly reduced in the three determinations in patients with gluten-induced enteropathy as compared to control subjects. Lactase and L-ALA-L-Phe hydrolase activities were significantly reduced (p less than 0.01) in CF patients as compared to control subjects. Definite hypolactasia was also observed in 23% of the children with CF. Uptake of lysine was normal in CF patients whereas that of phenylalanine and cycloleucine was reduced as compared to control subjects. This study suggests an intestinal component to the malabsorption of patients with CF.
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PMID:Small bowel mucosal dysfunction in patients with cystic fibrosis. 124 82

We have studied the absorption of 3-methylhistidine (3MH) in vitro and changes in its plasma concentration in preruminant calves after ingestion of milk containing 3MH under normal and malabsorptive conditions. Changes in 3MH concentration were compared to those in lysine, homoarginine (as a component of guanidinated caseine) and xylose, also added to milk. The absorption of 3MH in vitro was dose-dependent and was inhibited by leucine, indicating that 3 MH was transported in the same manner as neutral amino acids. After the ingestion of milk supplying 2.5-20 mumols (3MH)/kg body weight, 3MH increased dose-dependently within 1.75 h and reached maximal levels between 3 and 8 h. Lysine concentration initially parallelled the course of blood 3MH levels but dropped sooner. Homoarginine concentration did not increase until 2-4 h postprandially, probably as a consequence of the time needed for casein degradation. Xylose concentration increased as rapidly as 3MH and lysine concentration. Feeding a diet containing soybean protein for 36 d and administration of neomycine for 5 d to newborn calves induced malabsorption of xylose. However, 3MH absorption and caseine digestion, which increased after homoarginine absorption were not reduced.
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PMID:[Postprandial plasma variations of 3-methylhistidine compared to those of lysine, homoarginine and xylose on the normal conditions and in malabsorption in the suckling calf]. 170 Sep 10

Ligand binding activity of intrinsic factor-cobalamin receptor (IFCR) was determined in homogenates and isolated brush-border membranes (BBM) of ileum and kidney from dogs exhibiting simple autosomal recessive inheritance of selective cobalamin malabsorption (Fyfe, J. C., Giger, U., Hall, C. A., Jezyk, P. F., Klumpp, S. A., Levine, J. S., and Patterson, D. F. (1991) Pediatr. Res. 29, 24-31). IFCR activity of affected dog ileal homogenates was 3-4-fold higher than normal whereas IFCR activity in affected dog kidney homogenates was one-tenth of normal. The recovery of IFCR activity in the BBM of ileum and renal cortex of affected dogs was 30- and 20-fold less than normal, respectively. The dissociation constant (Kd) for intrinsic factor-cobalamin was similar in BBM of both tissues and was the same in affected and normal dogs. In the affected dog ileal BBM, activities of alkaline phosphatase and sucrase-isomaltase and vesicular transport of glucose and Na(+)-taurocholate were normal. Immunoblots showed no IFCR cross-reactive material in the ileal or renal BBM of affected dogs. IFCR purified by affinity chromatography from kidney of both normal and affected dogs had an Mr = 230,000. However, amino acid analysis revealed that the affected dog IFCR had more lysine than the normal, and protease cleavage of the purified IFCRs revealed different peptide maps. Asparagine-linked oligosaccharides of both proteins were sensitive to peptide N-glycosidase F cleavage, but only the affected dog IFCR was endoglycosidase H sensitive. These results suggest that cobalamin malabsorption in this canine family is caused by inefficient BBM expression of IFCR due to a mutation of IFCR and its retention in an early biosynthetic compartment.
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PMID:Defective brush-border expression of intrinsic factor-cobalamin receptor in canine inherited intestinal cobalamin malabsorption. 199 30

Plasma carnitine levels were determined in 17 patients maintained on long-term total parenteral nutrition (TPN) for a mean (+/- SEM) period of 69 +/- 11 months (range 12-196). All had severe malabsorption and were dependent on intravenous feeding. Plasma carnitine was determined by a modified Cederblad enzymatic method. Mean plasma carnitine was significantly below the mean normal for females (p less than 0.02) and borderline low for males (p = 0.07). In six patients the levels were below the low normal range, and in five others they were at the lowest levels of normal. Of the six patients with normal levels, three had elevated serum creatinine, indicating renal dysfunction which may by itself elevate plasma carnitine. In 10 patients the plasma levels of lysine (a carnitine precursor) were determined and found to be lower than normal (p less than 0.05). Plasma carnitine levels correlated positively with serum albumin (r = 0.62, p less than 0.05), and negatively with serum alkaline phosphatase (r = -0.64, p less than 0.05). Thus, patients maintained on long-term TPN may have low plasma carnitine, which could represent carnitine deficiency. The low plasma carnitine may be related to a deficiency of the carnitine precursor lysine. Further studies are required to determine the significance of the low plasma carnitine and whether carnitine supplementation should be required in long-term TPN.
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PMID:Low plasma carnitine in patients on prolonged total parenteral nutrition: association with low plasma lysine. 211 37

Before dietary treatment, no significant differences, except for alanine, were found in the amino acid pattern for 22 young mothers and 33 children with protein-energy malnutrition (PEM), the characteristic feature of the serum pattern being the imbalance between essential and non essential amino acids. Apart from lysine, the essential amino acid levels were all below normal. This imbalance may be detected readily from the abnormal values of some particularly sensitive ratios: phenylalanine/tyrosine, valine/glycine, non essential amino acids/essential amino acids and, above all, serine/threonine. A striking finding was the very low threonine levels in all subjects, including local controls and the extremely low tryptophan levels in malnourished children. Before treatment, almost all the erythrocyte amino acid levels as well as the E/S ratios (erythrocytes/serum) were found to be raised in 9 children, demonstrating their poor clinical status. The urinary amino acid level was similar in both, patients before treatment and local controls. The urinary threonine level was low, like in the serum. A normalisation in most of the amino acid levels in the serum was observed upon dietary rehabilitation although not yet significant in all of them. In urine a similar tendency was observed but it was significant for threonine and methionine only, after 2 weeks treatment. Some additional urinary amino acid assays revealed changes upon two weeks dietary rehabilitation that can be interpreted as an increased production of enzymes affected by PEM as well as a growth of the patients' muscular mass. Increased free amino acid losses in the stools, caused by diarrhoea due to secondary malabsorption, and various viral and bacterial infections accompanying malnutrition, illustrate the severity of the diarrhoea.
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PMID:Biochemical study of malnutrition. Part IV. Determination of amino acids in the serum, erythrocytes, urine and stool ultrafiltrates. 678 95

Blood samples were taken from six overweight women after an overnight fast on three different occasions, before an jejunoileal bypass operation and 1 and 6 months after the operation. The preoperative levels of several plasma free amino acids were significantly elevated, e.g. leucine, isoleucine, valine, lysine, phenylalanine, tyrosine, proline and glutamic acid. One month after the operation all indispensable plasma amino acid concentrations had fallen, in particular the levels of the branched-chain amino acids (BCAA), lysine and tryptophan. Among the dispensable amino acids, plasma tyrosine, arginine and ornithine concentrations were significantly reduced. No further changes of significance were observed in samples taken 5 months later. A close correlation was observed between the plasma levels of retinol-binding protein (RBP) and thyroxine-binding prealbumin (TBPA). One month after the operation the levels of RBP and TBPA had fallen slightly in two subjects and substantially in one subject. A test diet, containing crystalline amino acids, glucose and fat emulsion was given before operation and twice after the operation. Plasma amino acid changes were studied for a period of 2 hours after the meal. The increases in plasma levels following the test meal were lower for many amino acids after the operation. A linear correlation was found between the postprandial increases in BCAA concentrations and the levels of RBP and TBPA. By using complete, carefully defined diets in loading tests, it should be possible to screen for glucose tolerance and amino acid and lipid malabsorption.
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PMID:An oral amino acid loading test before and after intestinal bypass operation for morbid obesity. 713 14

We prepared corn peptide (CP), a vegetable oligopeptide and tried to discover the effects of its ingestion on facilitating alcohol metabolism in healthy adult men. Ten healthy male volunteers ingested 5 g of CP, wheat peptide (WP), pea peptide (PP), alanine, or leucine 30 min before alcohol intake at a dose of 0.5 g/kg, and blood ethanol and plasma amino acid concentrations were measured during a 2-h observation period after alcohol intake. In subjects who ingested CP, the blood ethanol level was lower than that in the WP, alanine and leucine ingestion groups, but did not decrease as compared to the control when they ingested PP. Similarly there was a difference in the blood ethanol level between alanine and leucine ingestion groups, and leucine ingestion was more effective than alanine against the reduction of the increase in blood ethanol level. On the other hand, there was no significant difference in the plasma concentrations of individual amino acids except alanine, leucine, or lysine after alcohol intake among experimental groups as compared to the control. CP ingestion significantly elevated plasma alanine and leucine rather than other groups during a 2-h observation period. These results suggested that CP may have the effect on the reduction of increase in blood ethanol level after alcohol intake by the marked elevation of plasma alanine and leucine, especially leucine, but neither by the delay of ethanol release from the stomach nor malabsorption of ethanol in the gastrointestinal tracts.
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PMID:The effects of corn peptide ingestion on facilitating alcohol metabolism in healthy men. 933 48

Our objective was to measure maternal plasma and amniotic fluid amino acid concentrations in pregnant women diagnosed as having fetuses with gastroschisis in the second trimester of pregnancy. Twenty-one pregnant women who had fetuses with gastroschisis detected by ultrasonography (gastroschisis group) in the second trimester and 32 women who had abnormal triple screenings indicating an increased risk for Down syndrome but had healthy fetuses (control group) were enrolled in the study. Amniotic fluid was obtained by amniocentesis, and maternal plasma samples were taken simultaneously. The chromosomal analysis of the study and control groups was normal. Levels of free amino acids and non-essential amino acids were measured in plasma and amniotic fluid samples using EZ:fast kits (EZ:fast GC/FID free (physiological) amino acid kit) by gas chromatography (Focus GC AI 3000 Thermo Finnigan analyzer). The mean levels of essential amino acids (histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine) and non-essential amino acids (alanine, glycine, proline, and tyrosine) in amniotic fluid were found to be significantly higher in fetuses with gastroschisis than in the control group (P < 0.05). A significant positive correlation between maternal plasma and amniotic fluid concentrations of essential and nonessential amino acids was found only in the gastroschisis group (P < 0.05). The detection of significantly higher amino acid concentrations in the amniotic fluid of fetuses with a gastroschisis defect than in healthy fetuses suggests the occurrence of amino acid malabsorption or of amino acid leakage from the fetus into amniotic fluid.
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PMID:Elevated amniotic fluid amino acid levels in fetuses with gastroschisis. 1690 76


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