Pattern of rat intestinal brush-border enzyme gene expression changes with epithelial growth state

1995 ◽  
Vol 269 (2) ◽  
pp. C385-C391 ◽  
Author(s):  
R. A. Hodin ◽  
S. M. Chamberlain ◽  
S. Meng
Keyword(s):  
Gene Expression ◽  
Alkaline Phosphatase ◽  
Brush Border ◽  
Longitudinal Axis ◽  
Mrna Levels ◽  
Intestinal Alkaline Phosphatase ◽  
Enzyme Gene ◽  
Growth State ◽  
Brush Border Enzyme ◽  
Epithelial Growth

Enterocyte growth and differentiation occur simultaneously within the epithelium, but little is known regarding any relationship between these two processes. Four rat models of small intestinal epithelial hypo- and hyperplasia (neonatal ontogeny, fasting/refeeding, hypo-/hyperthyroidism, and bombesin treatment) were used to study the regulation of enterocyte gene expression in relation to epithelial growth state. Mucosal scrapings, as well as crypt and villus cell populations, were subjected to Northern blot analyses using radiolabeled cDNA probes corresponding to lactase, intestinal alkaline phosphatase, villin, ornithine decarboxylase (ODC), and the actin control. In all four models, the hypoplastic (atrophic) condition is characterized by high levels of lactase and low levels of the 3.0-kb intestinal alkaline phosphatase mRNA, whereas under hyperplastic conditions this pattern is reversed. The changes in intestinal alkaline phosphatase and lactase are qualitatively similar along the longitudinal axis of the intestine and are proportional to the degree of hyperplasia, as verified by ODC mRNA levels. Furthermore, the crypt-villus axis of differentiation is maintained regardless of epithelial growth state. In conclusion, the pattern of brush-border enzyme gene expression changes as a function of epithelial growth state, indicating a previously unrecognized degree of plasticity to the state of enterocyte differentiation.

Thyroid hormone differentially regulates rat intestinal brush border enzyme gene expression

1992 ◽  
Vol 103 (5) ◽  
pp. 1529-1536 ◽  
Author(s):  
Richard A. Hodin ◽  
Sherman M. Chamberlain ◽  
Melissa P. Upton
Keyword(s):  
Gene Expression ◽  
Thyroid Hormone ◽  
Brush Border ◽  
Enzyme Gene ◽  
Intestinal Brush Border ◽  
Brush Border Enzyme

scholarly journals Role of lysophosphatidylcholine in brush-border intestinal alkaline phosphatase release and restoration

2009 ◽  
Vol 297 (1) ◽  
pp. G207-G214 ◽  
Author(s):  
Takanari Nakano ◽  
Ikuo Inoue ◽  
David H. Alpers ◽  
Yasutada Akiba ◽  
Shigehiro Katayama ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Brush Border ◽  
Cell Injury ◽  
Corn Oil ◽  
Sodium Taurocholate ◽  
Mrna Levels ◽  
Apical Surface ◽  
Intestinal Alkaline Phosphatase ◽  
Cell Monolayers ◽  
Lipid Micelles

Intestinal alkaline phosphatase (IAP) is a brush-border membrane ectoenzyme (BBM-IAP) that is released into the lumen (L-IAP) after a high-fat diet. We examined the effects of oil feeding and the addition of mixed-lipid micelles on the formation of L-IAP in oil-fed rat intestine, Caco-2 cell monolayers, and mouse intestinal loops. We localized IAP in the duodenum of rats fed corn oil using fluorescence microscopy with enzyme-labeled fluorescence-97 as substrate. Four hours after oil feeding, L-IAP increased ∼10-fold accompanied by the loss of BBM-IAP, consistent with BBM-IAP release. Rat IAP isozyme mRNAs progressively increased 4–6 h after oil feeding, followed by the increase of IAP activity in the subapical location at 6 h, consistent with the restoration of IAP protein. Postprandial lipid-micelle components, sodium taurocholate with or without oleic acid, mono-oleylglycerol, cholesterol, or lysophosphatidylcholine (lysoPC) were applied singly or as mixed-lipid micelles to the apical surface of polarized Caco-2 cell monolayers. LysoPC increased L-IAP >10-fold over basal release. LysoPC released IAP into the apical medium more than other intestinal brush-border enzymes, 5′-nucleotidase, sucrase, aminopeptidase N, and lactase, without comparable lactate dehydrogenase release or cell injury. LysoPC increased human IAP mRNA levels by 1.5-fold in Caco-2 cells. Luminally applied lysoPC also increased release of IAP preferentially in mouse intestinal loops. These data show that lysoPC accelerates the formation of L-IAP from BBM-IAP, followed by enhanced IAP synthesis, suggesting the role that lysoPC might play in the turnover of brush-border proteins.

Different diuresis-dependent excretions of urinary enzymes: N-acetyl-beta-D-glucosaminidase, alanine aminopeptidase, alkaline phosphatase, and gamma-glutamyltransferase.

1986 ◽  
Vol 32 (3) ◽  
pp. 529-532 ◽  
Author(s):  
K Jung ◽  
G Schulze ◽  
C Reinholdt
Keyword(s):  
Alkaline Phosphatase ◽  
Brush Border ◽  
Excretion Rate ◽  
Urine Flow ◽  
High Intake ◽  
Brush Border Enzymes ◽  
Urinary Creatinine ◽  
Gamma Glutamyltransferase ◽  
Alanine Aminopeptidase ◽  
Brush Border Enzyme

Abstract We studied how much of the lysosomal enzyme N-acetyl-beta-D-glucosaminidase (EC 3.2.1.30) and of the brush-border enzymes alanine aminopeptidase (EC 3.4.11.2), alkaline phosphatase (EC 3.1.3.1), and gamma-glutamyltransferase (EC 2.3.2.2) was excreted in urine over 8 h after a high intake of fluid (22 mL per kilogram of body weight). The hourly excretion of all four enzymes increased with the increasing urine flow rate. The excretion rate of the brush-border enzymes was more markedly influenced than that of N-acetyl-beta-D-glucosaminidase. By relating the enzyme excretion to urinary creatinine we could reduce the variability of brush-border enzyme output and could completely compensate for the effect of diuresis on the excretion of N-acetyl-beta-D-glucosaminidase.

Anion-stimulated ATPase activity of brush border from rat small intestine.

1979 ◽  
Vol 236 (1) ◽  
pp. E70 ◽  
Author(s):  
M H Humphreys ◽  
L Y Chou
Keyword(s):  
Alkaline Phosphatase ◽  
Atpase Activity ◽  
Brush Border ◽  
Atp Hydrolysis ◽  
Intestinal Transport ◽  
Mitochondrial Enzymes ◽  
Intestinal Alkaline Phosphatase ◽  
Ph Optimum ◽  
Low Concentrations ◽  
Small Intestinal

Differential centrifugation of rat small intestinal homogenates produced a crude brush border (BB) fraction that was enriched 15-fold for the marker enzymes, alkaline phosphatase and sucrase; contamination with mitochondrial enzymes, monoamine oxidase and succinate dehydrogenase, was minimal. ATP hydrolysis by this BB fraction was stimulated by addition of several anions to the incubation medium: HCO3 and Cl were equally effective in this regard, with NO3, NO2, SO4, and acetate being less stimulatory. SCN and CNO inhibited ATPase activity, whereas the divalent anion SO3 was stimulatory at low concentrations (less than 25 mM) but inhibitory at 100 mM. Maximum anion stimulation was observed at a Mg concentration of 0.5 mM, and pH optimum was 8.5. Kinetic analysis showed that HCO3 increased the Vmax without altering the Km for ATP; the Ka for this effect of HCO3 was 35 mM. This enzyme activity was completely inhibited by 20 mM L-phenylalanine, 10 mM L-cysteine, and 3 mM EDTA, compounds that also inhibited intestinal alkaline phosphatase. These results demonstrate the presence of anion-stimulated ATPase activity in rat small intestinal brush border and suggest that this activity may be related to intestinal alkaline phosphatase. The role of this enzyme in intestinal transport is not known, but could relate to the regulation of intestinal absorption and secretion.

scholarly journals Western-diet consumption induces alteration of barrier function mechanisms in the ileum that correlates with metabolic endotoxemia in rats

2017 ◽  
Vol 313 (2) ◽  
pp. E107-E120 ◽  
Author(s):  
Mathilde Guerville ◽  
Anaïs Leroy ◽  
Annaëlle Sinquin ◽  
Fabienne Laugerette ◽  
Marie-Caroline Michalski ◽  
...  
Keyword(s):  
Gene Expression ◽  
Elevated Serum ◽  
Caloric Intake ◽  
Western Diet ◽  
Chow Diet ◽  
Low Grade ◽  
Mrna Levels ◽  
Intestinal Alkaline Phosphatase ◽  
Ad Libitum ◽  
Metabolic Endotoxemia

Obesity and its related disorders have been associated with the presence in the blood of gut bacteria-derived lipopolysaccharides (LPS). However, the factors underlying this low-grade elevation in plasma LPS, so-called metabolic endotoxemia, are not fully elucidated. We aimed to investigate the effects of Western diet (WD) feeding on intestinal and hepatic LPS handling mechanisms in a rat model of diet-induced obesity (DIO). Rats were fed either a standard chow diet (C) or a Western Diet (WD, 45% fat) for 6 wk. They were either fed ad libitum or pair-fed to match the caloric intake of C rats for the first week, then fed ad libitum for the remaining 5 wk. Six-week WD feeding led to a mild obese phenotype with increased adiposity and elevated serum LPS-binding protein (LBP) levels relative to C rats, irrespective of initial energy intake. Serum LPS was not different between dietary groups but exhibited strong variability. Disrupted ileal mucus secretion and decreased ileal Reg3-γ and -β gene expression along with high ileal permeability to LPS were observed in WD compared with C-fed rats. Ileal and cecal intestinal alkaline phosphatase (IAP) activity as well as Verrucomicrobia and Bifidobacterium cecal levels were increased in WD-fed rats compared with C-fed rats. WD consumption did not impact mRNA levels of LPS-handling hepatic enzymes. Correlation analysis revealed that ileal passage of LPS, IAP activity, Proteobacteria levels and hepatic aoah gene expression correlated with serum LPS and LBP, suggesting that ileal mucosal defense impairment induced by WD feeding contribute to metabolic endotoxemia.

Altered skeletal pattern of gene expression in response to spaceflight and hindlimb elevation

1994 ◽  
Vol 267 (6) ◽  
pp. E822-E827 ◽  
Author(s):  
D. D. Bikle ◽  
J. Harris ◽  
B. P. Halloran ◽  
E. Morey-Holton
Keyword(s):  
Gene Expression ◽  
Alkaline Phosphatase ◽  
Bone Formation ◽  
Bone Mineralization ◽  
Mrna Levels ◽  
Skeletal Unloading ◽  
Compensatory Response ◽  
Factor I ◽  
Igf I ◽  
Skeletal Pattern

Spaceflight leads to osteopenia, in part by inhibiting bone formation. Using an animal model (hindlimb elevation) that simulates the weightlessness of spaceflight, we and others showed a reversible inhibition of bone formation and bone mineralization. In this study, we have measured the mRNA levels of insulin-like growth factor I (IGF-I), IGF-I receptor (IGF-IR), alkaline phosphatase, and osteocalcin in the tibiae of rats flown aboard National Aeronautics and Space Administration Shuttle Flight STS-54 and compared the results with those obtained from their ground-based controls and from the bones of hindlimb-elevated animals. Spaceflight and hindlimb elevation transiently increase the mRNA levels for IGF-I, IGF-IR, and alkaline phosphatase but decrease the mRNA levels for osteocalcin. The changes in osteocalcin and alkaline phosphatase mRNA levels are consistent with a shift toward decreased maturation, whereas the rise in IGF-I and IGF-IR mRNA levels may indicate a compensatory response to the fall in bone formation. We conclude that skeletal unloading during spaceflight or hindlimb elevation resets the pattern of gene expression in the osteoblast, giving it a less mature profile.

Presence of γ-glutamyltransferase in the renal microvascular compartment

1981 ◽  
Vol 59 (6) ◽  
pp. 383-386 ◽  
Author(s):  
P. D. Dass ◽  
R. P. Misra ◽  
T. C. Welbourne
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Density Gradient ◽  
Alkaline Phosphatase Activity ◽  
Brush Border ◽  
Sucrose Density Gradient ◽  
Isolated Glomeruli ◽  
Crude Homogenate ◽  
Brush Border Enzyme ◽  
Enzyme Alkaline Phosphatase

The association between the brush border enzyme alkaline phosphatase and γ-glutamyltransferase was determined by sucrose density gradient analysis of crude kidney homogenates, isolated glomeruli, and isolated microvessels. As previously established there is an overlap of these enzyme activities in the crude homogenate corresponding to a density of 1.17 g∙cm−3. In contrast, isolated glomeruli sedimented with a peak of 1.25 g∙cm−3 and exhibited γ-glutamyltransferase activity but little alkaline phosphatase activity; homogenizing isolated glomeruli shifted the fragments to a density coincident with that observed for the crude homogenate γ-glutamyltransferase peak. A second population of capillaries, isolated microvessels, were homogenized and analyzed on the sucrose density gradient. These fragments sedimented over the same range as crude homogenate γ-glutamyltransferase peak but were devoid of alkaline phosphatase activity and yet exhibited remarkable γ-glutamyltransferase activity. The results indicate homogenization of renal cortex results in a heterogenous collection of particles from both tubular and microvascular locations exhibiting γ-glutamyltransferase activity which overlap with the brush border alkaline phosphatase containing membranes. However, isolation of microvessels and glomeruli prior to homogenization allows separation of γ-glutamyltransferase from alkaline phosphatase activity; between 10 and 20% of the total homogenate γ-glutamyltransferase activity is estimated to be associated with the microvascular compartment.

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