Early effects on the intestinal barrier and pancreatic function after enteral stimulation with protease or kidney bean lectin in neonatal rats

AbstractGut maturation naturally accelerates at weaning in altricial mammalian species, such as the rat. Mimicking this, gut development can also be induced precociously, 3–4 d earlier than it would occur naturally, by enteral exposure to phytohaemagglutinin (PHA), or various proteases. We investigated the early effects of gut provocation on intestinal barrier and pancreatic functions, to get a better understanding of the mechanisms that initiate gut maturation. The effects of oral administration of protease (trypsin) or PHA to 14-d-old suckling rats were studied during 24 h in comparison with water-fed controls. Intestinal in vivo permeability was assessed by oral administration of different-sized marker molecules and measuring their passage into the blood or urine 3 h later. A period of 24 h following oral administration, both PHA and protease provocation stimulated small intestinal (SI) growth and pancreatic secretion, as indicated by decreased pancreatic trypsin and increased luminal enzyme content. Within 1 h of oral administration, both treatments prevented the absorption of macromolecules to blood that was observed in controls. PHA treatment hindered the passage of fluorescein isothiocyanate-dextran (FD) 4 to blood, whereas protease treatment temporarily increased plasma levels of FD4, and the urine lactulose:mannitol ratio, indicating increased intestinal leakiness. Following protease treatment, fluorescence microscopy showed decreased vesicular uptake of FD70 in the proximal SI and increased epithelial fluorescence in the distal SI. In conclusion, PHA and protease differed in their early effects on the intestinal barrier; both exerted a blocking effect on epithelial endocytosis, whereas protease treatment alone temporarily increased epithelial leakiness, which seemed to be confined to the distal SI.

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Spray-Dried Plasma Improves Body Weight, Intestinal Barrier Function, and Tibia Strength during Experimental Constant Heat Stress Conditions

Animals ◽

10.3390/ani11082213 ◽

2021 ◽

Vol 11 (8) ◽

pp. 2213

Author(s):

Jared Ruff ◽

Thaina L. Barros ◽

Joy Campbell ◽

Ricardo González-Esquerra ◽

Christine N. Vuong ◽

...

Keyword(s):

Heat Stress ◽

Intestinal Barrier ◽

Fluorescein Isothiocyanate ◽

Serum Levels ◽

Negative Control ◽

Intestinal Barrier Function ◽

Negative Consequences ◽

Fluorescein Isothiocyanate Dextran ◽

Prolonged Heat ◽

Spray Dried

The aim of this study was to see how spray-dried plasma (SDP) supplementation affected broiler chicken performance, intestinal permeability, and bone strength during persistent heat stress. One-day-old chicks (n = 480) were randomly assigned into twelve environmental corrals; four thermoneutral (TN-negative control, maintained at 24 °C from d 21–42); four heat stress (HS, exposed to 35 °C from d 21–42); and four heat stress treated with 2% SDP in the feed until d 28 followed by 1% SDP until d 42 (HS-SDP). The performance and serum levels of fluorescein isothiocyanate-dextran (FITC-d) were evaluated at d 21, 28, 35, and 42. The tibias strength was evaluated on d 21 and 42. The increment in chicken temperature (p < 0.05) was observed two h following the increase in environmental temperature in both HS groups and was associated with decreased performance parameters compared with the TN group. At d 42 of age, the chickens exposed to HS had an impaired gut permeability and decreased tibia strength compared to the TN group (p < 0.05). However, partially feeding SDP mitigated these adverse effects significantly. These findings imply that using SDP strategically during stressful times, such as prolonged heat stress, may help mitigate its negative consequences.

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In-vivo Buccal Delivery of Fluorescein Isothiocyanate–Dextran 4400 with Glycodeoxycholate as an Absorption Enhancer in Pigs

Journal of Pharmaceutical Sciences ◽

10.1021/js950129k ◽

1996 ◽

Vol 85 (5) ◽

pp. 457-460 ◽

Cited By ~ 43

Author(s):

A.J. Hoogstraate ◽

J.C. Verhoef ◽

B. Tuk ◽

A. Pijpers ◽

L.A.M.G. van Leengoed ◽

...

Keyword(s):

Fluorescein Isothiocyanate ◽

Absorption Enhancer ◽

Buccal Delivery ◽

Fluorescein Isothiocyanate Dextran

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Aflatoxin B1 and Aflatoxin M1 Induce Compromised Intestinal Integrity through Clathrin-Mediated Endocytosis

Toxins ◽

10.3390/toxins13030184 ◽

2021 ◽

Vol 13 (3) ◽

pp. 184

Author(s):

Yanan Gao ◽

Xiaoyu Bao ◽

Lu Meng ◽

Huimin Liu ◽

Jiaqi Wang ◽

...

Keyword(s):

Aflatoxin B1 ◽

Intestinal Barrier ◽

Fluorescein Isothiocyanate ◽

Intestinal Barrier Function ◽

Aflatoxin M1 ◽

Dependent Manner ◽

Simultaneous Exposure ◽

Intestinal Integrity

With the growing diversity and complexity of diet, humans are at risk of simultaneous exposure to aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1), which are well-known contaminants in dairy and other agricultural products worldwide. The intestine represents the first barrier against external contaminants; however, evidence about the combined effect of AFB1 and AFM1 on intestinal integrity is lacking. In vivo, the serum biochemical parameters related to intestinal barrier function, ratio of villus height/crypt depth, and distribution pattern of claudin-1 and zonula occluden-1 were significantly affected in mice exposed to 0.3 mg/kg b.w. AFB1 and 3.0 mg/kg b.w. AFM1. In vitro results on differentiated Caco-2 cells showed that individual and combined AFB1 (0.5 and 4 μg/mL) and AFM1 (0.5 and 4 μg/mL) decreased cell viability and trans-epithelial electrical resistance values as well as increased paracellular permeability of fluorescein isothiocyanate-dextran in a dose-dependent manner. Furthermore, AFM1 aggravated AFB1-induced compromised intestinal barrier, as demonstrated by the down-regulation of tight junction proteins and their redistribution, particularly internalization. Adding the inhibitor chlorpromazine illustrated that clathrin-mediated endocytosis partially contributed to the compromised intestinal integrity. Synergistic and additive effects were the predominant interactions, suggesting that these toxins are likely to have negative effects on human health.

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Influence of osmolality on gastrointestinal fluid volume and drug absorption: potential impact on oral salt supplementation

Journal of Pharmaceutical Health Care and Sciences ◽

10.1186/s40780-021-00212-z ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Miyuki Takemura ◽

Yuki Tanaka ◽

Katsuhisa Inoue ◽

Ikumi Tamai ◽

Yoshiyuki Shirasaka

Keyword(s):

Drug Absorption ◽

Fluorescein Isothiocyanate ◽

Fluid Volume ◽

Gi Tract ◽

Gastrointestinal Fluid ◽

Fraction Absorbed ◽

Absorption Potential ◽

Fluorescein Isothiocyanate Dextran

Abstract Background The syndrome of inappropriate secretion of antidiuretic hormone (SIADH) is the most frequent cause of hyponatremia in patients with cerebrovascular disease, and is often treated with oral salt tablets. However, we have shown that osmolality-dependent variations in gastrointestinal (GI) fluid volume can alter the concentration of a poorly permeable drug in the GI tract, potentially affecting its absorption. Here, we examined the effect of ingestion of hyperosmotic solution (10% NaCl) on drug concentration and absorption in the GI tract. Methods The effects of osmolality on luminal fluid volume and drug absorption in rat intestine (jejunum, ileum and colon) were examined by means of an in situ closed loop method using fluorescein isothiocyanate-dextran 4000 (FD-4) and atenolol. In vivo absorption in rats was determined by measuring the plasma concentration after oral administration of the test compounds dissolved in purified water or hyperosmotic solution (10% NaCl). Results Administration of hyperosmotic solution directly into the GI tract significantly increased the GI fluid volume, owing to secretion of water into the lumen. After administration in hyperosmotic solution, the luminal concentration of non-permeable FD-4 was significantly lower than the initial dosing concentration, whereas after administration in purified water, the luminal concentration exceeded the initial concentration. The fraction absorbed of atenolol was markedly lower after administration in hyperosmotic solution than after administration in purified water. An in vivo pharmacokinetic study in rats was consistent with these findings. Conclusions Administration of hyperosmotic NaCl solution increased GI fluid volume and reduced the plasma level of orally administered atenolol. This may imply that oral salt tablets used to treat hyponatremia in SIADH patients could decrease the intestinal absorption of concomitantly administered drugs, resulting in lower plasma exposure.

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In Vivo Effects of A Pro-PO System Inhibitor on the Phagocytosis of Xenorhabdus Nematophila in Galleria Mellonella Larvae

Insects ◽

10.3390/insects10090263 ◽

2019 ◽

Vol 10 (9) ◽

pp. 263 ◽

Cited By ~ 2

Author(s):

Andrea De Lerma Barbaro ◽

Marzia B. Gariboldi ◽

Maristella Mastore ◽

Maurizio F. Brivio ◽

Stefano Giovannardi

Keyword(s):

Cell Wall ◽

Galleria Mellonella ◽

Mammalian Species ◽

Specific Inhibitor ◽

Fluorescein Isothiocyanate ◽

Structural Features ◽

In Vitro Tests ◽

Xenorhabdus Nematophila

Xenorhabdus nematophila is a Gram-negative bacterium symbiont of the entomopathogen nematode Steinernema carpocapsae whose immunosuppressive properties over host’s immune response have been thoroughly investigated. In particular, live X. nematophila actively impairs phagocytosis in host’s hemocytes through the secretion of inhibitors of eicosanoids synthesis. In this article we have investigated the cell surface structural features of X. nematophila responsible for the elusion from phagocytosis. To this end we have studied the uptake of heat-killed (hk), fluorescein isothiocyanate (FITC)-labeled X. nematophila by phagocytes from both a host insect and a mammalian species. In vitro dead X. nematophila passively resists engulfment by insect hemocytes without impairing the phagocytosis machinery whereas, unexpectedly, in vivo a significant phagocytosis of dead X. nematophila was observed. X. nematophila in vivo phagocytosis was increased by the co-injection of the specific inhibitor of pro-phenoloxidase (PO) system phenylthiourea (PTU), even if these effects were not observed in in vitro tests. Furthermore, biochemical modifications of X. nematophila cell wall implement in vivo phagocytosis, suggesting that this bacterium avoid phagocytosis because the ligand of phagocytic receptors is somehow buried or disguised in the cell wall. Finally, dead X. nematophila escapes engulfment even by human phagocytes suggesting that X. nematophila could be a useful model to investigate escape from phagocytosis by mammalian macrophages.

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Cigarette smoke extract potentiates bradykinin-induced increases in microvascular permeability

Journal of Applied Physiology ◽

10.1152/jappl.1993.75.1.27 ◽

1993 ◽

Vol 75 (1) ◽

pp. 27-32 ◽

Cited By ~ 5

Author(s):

W. G. Mayhan ◽

I. Rubinstein

Keyword(s):

Cigarette Smoke ◽

Fluorescein Isothiocyanate ◽

Cigarette Smoke Extract ◽

Microvascular Permeability ◽

Cheek Pouch ◽

Site Formation ◽

Hamster Cheek Pouch ◽

Fluorescein Isothiocyanate Dextran ◽

Macromolecular Permeability

The first goal of this study was to determine whether cigarette smoke extract (CSE) increases microvascular permeability of the hamster cheek pouch in vivo. The second goal was to determine whether CSE potentiates bradykinin-induced increases in vascular permeability in the hamster cheek pouch. Using intravital microscopy, we examined the permeability of the hamster cheek pouch to fluorescein isothiocyanate-dextran (mol wt 70,000). Increases in permeability were quantitated by counting the number of postcapillary venular leaky sites per 0.11 cm2. Superfusion of CSE (1, 5, and 10%) did not produce venular leaky sites and, thus, did not alter macromolecular permeability. Superfusion of bradykinin (0.1, 0.5, and 1.0 microM) produced a dose-related increase in the number of venular leaky sites. Formation of leaky sites in response to bradykinin was potentiated by CSE. To determine whether potentiation of bradykinin-induced leaky site formation by CSE was related to products released via the cyclooxygenase pathway, we examined the effects of pretreatment with indomethacin (10 mg/kg i.v.). Indomethacin did not alter the potentiating effect of CSE on bradykinin-induced leaky site formation. These findings suggest that CSE does not alter basal permeability of the hamster cheek pouch microcirculation in vivo. However, CSE potentiates bradykinin-induced increases in microvascular permeability. The mechanism of CSE-induced potentiation of microvascular permeability does not appear to be related to substances produced via the cyclooxygenase pathway.

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The brush border of rabbit kidney, a cellular compartment free of glycolytic enzymes

Biochemical Journal ◽

10.1042/bj1740509 ◽

1978 ◽

Vol 174 (2) ◽

pp. 509-515 ◽

Cited By ~ 6

Author(s):

Dietrich Busse ◽

Hans Ulrich Wahle ◽

Harald Bartel ◽

Barbara Pohl

Keyword(s):

Lactate Dehydrogenase ◽

Pyruvate Kinase ◽

Brush Border ◽

Gradient Centrifugation ◽

Fluorescein Isothiocyanate ◽

Glycolytic Enzymes ◽

Rabbit Kidney ◽

Cellular Compartment ◽

Fluorescein Isothiocyanate Dextran

Activities of four enzymes of the glycolytic pathway, hexokinase, glyceraldehyde 3-phosphate dehydrogenase, pyruvate kinase and lactate dehydrogenase, were determined in a vesicular brush-border preparation from rabbit kidneys. The specific activities of the enzymes were decreased several-hundredfold in the brush-border preparation compared with a kidney homogenate, but the enzymes were not totally absent. Density-gradient centrifugation of the brush-border preparation yielded brush border of even higher purity and also a characteristic pattern of distribution for each of the contaminating intracellular membranes. The presence of hexokinase in the brush-border preparation could be traced to contaminating mitochondria, and that of glyceraldehyde 3-phosphate dehydrogenase, pyruvate kinase and lactate dehydrogenase to contaminating vesicles derived from the endoplasmic reticulum. The brush-border vesicles contained some ATP. An intravesicular concentration of 0.1mm was estimated, indicating that the vesicles had retained at least a part of their original content. Experiments in which fluorescein isothiocyanate-dextran (mol.wt. 20000) was present during cell lysis revealed that much, but not all, of the brush-border contents had been exchanged with the medium. The complete absence of glycolytic enzymes from brush-border vesicles, which had retained part of their original content, indicates that the brush border does not contain glycolytic enzymes in vivo and can be thought of as a compartment of its own, somehow separated from the cytoplasm.

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