DigitalUM :: Browsing by Subject "Intestine"

Browsing by Subject "Intestine"

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Open Access
Changes in intestinal endocrine cells in the mouse after unilateral cervical vagotomy
(Murcia : F. Hernández, 1999) Qian, B.F.; El-Salhy, M.; Danielsson, A.; Shalaby, A.; Axelsson, H.
The effect of right or left unilateral cervical vagotomy on the intestinal endocrine cells was studied in 23 mice at 2 and 8 weeks after operation, respectively. The results were compared with that from 10 sham operated mice. Various types of endocrine cells in duodenum and proximal colon were detected by immunohistochemistry and quantified by computerized image analysis. In mouse duodenum, chromogranin-, CCKIgastrin-, GIP- and somatostatin-cells were significantly decreased at 2 weeks after right vagotomy, but returned to the control levels at 8 weeks. Serotonincells were reduced at both 2 and 8 weeks after right vagotomy. The amount of the duodenal endocrine cells did not change after left vagotomy with the exception of secretin-cells, which were diminished at 8 weeks after both right and left vagotomy. In the proximal colon, chromogranin-cells were also decreased at 2 weeks after right vagotomy. Serotonin-cells were reduced at 8 weeks after left vagotomy but not right vagotomy. There was no significant difference between the unilaterally vagotomized and the sham operated mice with regard to PYY- and glucagon-cells. It was concluded that vagotomy affected the intestinal endocrine cells in mouse. The influence was more pronounced in the small intestine than the proximal colon. The right vagus nerves seemed to exert more effect on the intestinal endocrine cells than the left ones.
Open Access
Chronic morpho-functional damage as a consequence of transient ischemia-reperfusion injury of the small bowel
(Murcia : F. Hernández, 2010) Morini, Sergio; Elias, Georg; Brown, Melisa; Subbotin, Vladimir; Rastellini, Cristiana; Cicalese, Luca
Introduction: The prevailing notion is thatischemia reperfusion injury of the small bowel inducestransient changes that resolve within a few days post-occurrence. However, chronic injury has been describedfollowing a single ischemia reperfusion in the kidney.We proceeded to ascertain if a similar outcome is alsowitnessed in the small bowel. Materials and methods:ACI rats (n=32) underwent 1, 2 or 3 episodes ofischemia reperfusion by clamping the superiormesenteric artery for 45 minutes at 7-day intervals.Control groups included sham-operated (n=6) or non-operated (n=5) rats. Morphology was examined at dayninety post-ischemia reperfusion and immunostainingwas used to evaluate macrophage infiltration,microvascular distribution, and apoptosis. RT-PCR wasused to evaluate expression of Inter-Cellular AdhesionMolecule-1 (ICAM-1), transforming growth factor-ß(TGF-ß), Insulin Growth Factor-I (IGF-1), and InsulinGrowth Factor-I Receptor (IGF-R). Intestinal functionwas evaluated by D-xylose performed 24 hours and 4, 8,and 12 weeks after reperfusion. Results: Chronicmorphologic changes were observed with degenerationof crypts, endothelial damage, matrix degeneration, andheightened lymphocyte degeneration within the Payer’spatches. Major structural changes were characterized byvillous atrophy from partial to total. The grade ofhistological injuries was significantly increased(P<0.001) after multiple ischemia reperfusion episodes.A higher number of apoptotic cells (P<0.001) and aprominent macrophage infiltration (P<0.05) was alsowitnessed. Altered expression of ICAM-1, TGF-ß, andIGF-1 was observed. At 24 hours after ischemiareperfusion D-xylose absorption was diminished,returning to baseline values within 4 weeks and becoming abnormal again at 8 and 12 weeks (P<0.05).CONCLUSIONS: Unlike the prevailing conviction,these data demonstrate that transient ischemiareperfusion repeated injuries of the small bowel result inchronic intestinal damage.
Open Access
Correspondence of gradual developmental increases of expression of galectin-reactive glycoconjugates with alterations of the total contents of the two differentially regulated galectins in chicken intestine and liver as indication for overlapping functions
(Murcia : F. Hernández, 1999) Lips, K.S.; Kaltner, H.; Reuter, G.; Stierstorfer, B.; Sinowatz, F.; Gabius, H.J.
The duplication of genes for recognition molecules and the ensuing diversification of the members of such families generate complex groups of homologous proteins. One example are galactosidespecific lectins whose sequences display constant features related to sugar binding, the galectins. Based on the inverse abundance of the chicken galectins CG-14 and CG-16 in adult intestine and liver, these two lectins represent a model to comparatively study expression of the related proteins and the galectin-reactive sites (glycoproteins and glycolipids) biochemically and histochemically. Functional overlap andtor acquisition of distinct functions would be reflected in qualitative andlor quantitative aspects of ligand display. Using five different stages of embryogenesis, differential regulation of the two galectins was detected in liver and intestine. The clear preference for one galectin (CC-14) was observed in intestine already at rather early stages, whereas equivalence for both proteins was noted in liver from day 12 to day 18 prior to hatching, as seen by ELISA assays and Western blot analysis. Presentation of galectin-reactive glycoproteins showed a tendency for gradual increase in both organs. Galectin-blotting analysis revealed primarily very similar patterns of positive bands at the different stages of development and only few quantitative and qualitative changes. The reactivity of glycolipids in a solid-phase assay was more variable, even surpassing the response of extracts of the adult organ at several embryonic stages. While the localization patterns of the galectins and galectinreactive sites were nearly indistinguishable in the liver, intestinal tissue differed with respect to the placement and accessibility of binding sites. Thus, the results suggest a differential regulation of galectin activities in the two organs. As a sum they resemble the course of development of availability of glycoprotein ligands in vitro. These findings support the notion for a partial functional redundancy in this family. The described approach to employ galectin-specific antibodies and the labeled galectins as tools to assess presentation of ligands is suggested to be of general relevance to address the question of distinct vs. overlapping functions of related recognition molecules.
Open Access
Effects of a probiotic on the morphology and mucin composition of pig intestine
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Desantis, Salvatore; Mastrodonato, Maria; Accogli, Gianluca; Rossi, Giacomo; Crovace, Alberto Maria
Although the use of probiotics in human and animal medicine is growing, their mode of action remains poorly understood. This study examined the effects of a multi-strain probiotic (SLAB51™) on the morphology and carbohydrate composition of mucins secreted by goblet cells of intestinal crypts in growingfinishing pigs. Sections of duodenum, caecum and colon from pigs fed for 12 weeks with an orally administered control basal diet (No-Pro) or one with a probiotic blend (Pro) were processed for microscopic analysis and stained with (1) haematoxylin-eosin for structural and morphometrical investigation; (2) conventional histochemistry (periodic acid-Schiff, Alcian Blue pH 2.5, high iron diamine staining) for neutral, acidic nonsulphated, and sulphated mucin analysis; and (3) FITClabelled MAA-II and SNA lectins for α2,3- and α2,6- sialomucin identification. Compared with No-Pro samples, Pro samples displayed (1) increased goblet cell numbers in all investigated tract crypts; (2) an increase in acidic non-sulphomucins but a decrease in neutral, sulphated and α2,6-sialomucin-secreting goblet cells in the duodenum; (3) decreased crypt depth, an increase in α2,6-sialomucin secretory goblet cells, and a loss of goblet cell-secreting α2,3-sialomucins, which appeared on the apical surface of crypt fundus epithelial cells in the caecum; and (4) an increase in α2,6-sialomucinproducing goblet cells in the colon. Results suggest that treatment with SLAB51™ induces region-specific changes in the morphology and carbohydrate composition of mucins secreted along intestinal tracts of growing-finishing pigs. These changes could ameliorate the health status of the animals, which displayed higher growth performance and meat quality than controls (Tufarelli et al., 2017).
Open Access
Effects of irradiation on intestinal cells in vivo and in vitro
(Murcia : F. Hernández, 2002) Wróblewski, R.; Wróblewski, J.; Jalnäs, M.; Van Decker, G.; Björk, J.; Roomans, G.M.
The effects of irradiation on intestinal epithelial cells were analyzed in vivo and in vitro. The in vivo study was carried out on the rat small intestine and for the in vitro study the intestinal crypt cell-line IEC-6 was used. Rat intestine and IEC-6 cells were irradiated with X-ray doses ranging between 1-16 Gy. Energ y - dispersive X-ray microanalysis was used for detection of the elemental changes in the cells. Cell morphology was investigated in the scanning electron microscope, DNAsynthesis by autoradiography of 3H - t h y m i d i n e incorporating nuclei and proliferation by cell counting. Our results indicate that in vivo, in the crypt cells, the increasing doses of irradiation led to increased sodium and lowered potassium and phosphorus concentrations. Corresponding ion shifts were found in the irradiated IEC-6 cells. Cells continued to proliferate up to the dose of 8 Gy, although the proliferation rate became lower with increasing dose of irradiation. The increasing dose of irradiation significantly reduced DNA-synthesis (16 Gy decreased DNA-synthesis by 50%) which resulted in a complete inhibition of cell proliferation. Analysis of goblet cells also showed characteristic radiationdependent elemental changes. Scanning electron microscopical investigation of cells in culture revealed that most of the control cells were flat and had rather smooth cell membranes. Irradiation led to the appearance of numerous different membrane manifestations (microvilli of varying length and distribution, and blebs). Frequency of differences in the topology of the cells was related to the dose of irradiation. Our study clearly demonstrates that even low doses of irradiation cause changes in the ionic composition of the cells and inhibit DNA-synthesis and cell proliferation. The effects observed in the crypt cells in vivo were the same as in the intestinal cell line i n v i t ro, which indicates that IEC-6 cells can be used for investigation of side effects of radiation to the abdomen.
Open Access
Epithelial apoptosis in mechanistically distinct methods of injury in the murine small intestine
(Murcia : F. Hernández, 2007) Vyas, D.; Robertson, C.M.; Stromberg, P.E.; Martin, J.R.; Dunne, W.M.; Houchen, C.W.; Barrett, T.A.; Ayala, A.; Perl, M.; Buchman, T.G.; Coopersmith, C.M.
Gut epithelial apoptosis is involved in the pathophysiology of multiple diseases. This study characterized intestinal apoptosis in three mechanistically distinct injuries with different kinetics of cell death. FVB/N mice were subjected to gamma radiation, Pseudomonas aeruginosa pneumonia or injection of monoclonal anti-CD3 antibody and sacrificed 4, 12, or 24 hours post-injury (n=10/time point). Apoptosis was quantified in the jejunum by hematoxylin and eosin (H&E), active caspase-3, terminal deoxynucleotidyl transferase dUTP-mediated nick end labeling (TUNEL), in situ oligoligation reaction (ISOL,) cytokeratin 18, and annexin V staining. Reproducible results were obtained only for H&E, active caspase-3, TUNEL and ISOL, which were quantified and compared against each other for each injury at each time point. Kinetics of injury were different with early apoptosis highest following radiation, late apoptosis highest following anti CD3, and more consistent levels following pneumonia. ISOL was the most consistent stain and was always statistically indistinguishable from at least 2 stains. In contrast, active caspase-3 demonstrated lower levels of apoptosis, while the TUNEL assay had higher levels of apoptosis in the most severely injured intestine regardless of mechanism of injury. H&E was a statistical outlier more commonly mechanism or kinetics of injury, ISOL correlates to other quantification methods of detecting gut epithelial apoptosis more than any other method studied and compares favorably to other commonly accepted techniques of quantifying apoptosis in a large intestinal cross sectional by balancing sensitivity and specificity across a range of times and levels of death.
Open Access
Ets transcription factors in intestinal morphogenesis, homeostasis and disease
(Murcia : F. Hernández, 2008) Jedlicka, Paul; Gutierrez-Hartmann, Arthur
Ets transcription factors comprise a large family of sequence-specific regulators of gene expression with important and diverse roles in development and disease. Most Ets family members are expressed in the developing and/or mature intestine, frequently in a compartment-specific and temporally dynamic manner. However, with the exception of the highly expressed Elf3, involved in embryonic epithelial differentiation, little is known about Ets functions in intestinal development and homeostasis. Ets factors show altered expression in colon cancer, where they regulate pathways relevant to tumor progression. Ets factors also likely act as important modifiers of nonneoplastic intestinal disease by regulating pathways relevant to tissue injury and repair. Despite a large body of published work on Ets biology, much remains to be learned about the precise functions of this large and diverse gene family in intestinal morphogenesis, homeostasis, and both neoplastic and non-neoplastic pathology.
Open Access
Ferroportin is expressed on the mucous granule membrane of a subpopulation of goblet cells in the duodenum of the rat
(Murcia : F. Hernández, 2005) Oates, P.S.; Thomas, C.
Ferroportin is a basolateral transporter involved in the release of iron from cells. In addition to expression on the basolateral membrane of enterocytes, ferroportin is also seen on the microvillus membrane. This led us to consider that ferroportin might be expressed by other cells of the intestine where it contributes to iron metabolism. Ferroportin gene and protein expression in rat duodenum was studied by in situ hybridisation and immunohistochemistry, respectively in rats with different efficiencies of iron absorption. Ferroportin mRNA localised to enterocytes of the villus only. Ferroportin was demonstrated in enterocytes and in 30% of goblet cells. In goblet cells it localised to the mucous granule membrane. In ironloaded intestine some goblet cells contained iron suggesting that ferroportin may transport iron into the mucous granule where it would be lost during discharge of mucous. The finding of ferroportin in iron deficient goblet cells also suggests an additional role to iron excretion.
Open Access
Histopathology of human small intestinal and colonic ischemia-reperfusion: Experiences from human IR-models
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2019) Leenarts, Claire A.J.I.; Grootjans, Joep; Hundscheid, Inca H.; Schellekens, Dirk H.S.M.; Lenaerts, Kaatje; Buurman, Wim A.; Dejong, Cornelis H.C.; Derikx, Joep P.M.
Intestinal ischemia-reperfusion (IR) injury is a frequent, but potentially life-threatening condition. Although much has been learned about its pathophysiology from animal IR models, the translation to the human setting is imperative for better understanding of its etiology. This could provide us with new insight into development of early detection and potential new therapeutic strategies. Over the past decade, we have studied the pathophysiology of human small intestinal and colonic ischemia-reperfusion (IR) in newly developed human in vivo IR models. In this review, we give an overview of new insights on the sequelae of human intestinal IR, with particular attention for the differences in histopathology between small intestinal and colonic IR.
Open Access
ldentification of the interstitial cells of Cajal
(Murcia : F. Hernández, 1996) Komuro, T.; Tokui, K.; Zhou, D.S.
Observation of whole-mount stretch preparations using the zinc-iodide-osmic acid method reveals a wide variety of interstitial cells in different tissue layers of the guinea-pig small intestine. And a subsequent electron microscopic exarnination and survey of references makes clear that the interstitial cells of Cajal (ICC) depicted in original drawings of Cajal are heterogeneous and correspond to different types of interstitial cells. The myenteric ICC are characterized by long dichotomous branching processes which constitute cellular networks independent from the nerve plexus and form many gap junctions at their tips. Their ultrastructure is similar to that of fibroblasts and they have no basal lamina. The myenteric ICC show strong immunoreactivity for vimentin and the c-kit receptor, and probably correspond to the intestinal pacemaker cells. Within the circular muscle layer, ICC are represented by the cells that are closely associated with fine nerve bundles. The ICC have various shapes, ranging from bipolar to stellate, depending on the running pattern of the nerve fibers that they are associated with. They show fibroblast-like ultrastnicture and have no basal lamina. They form gap junctions with smooth muscle cells and are immunoreactive for vimentin. On the other hand, ICC associated with the deep muscular plexus described in the guinea-pig by Cajal could not be clearly identified. However, it is suggested that the ICC in this location may correspond to glycogen-rich cells possessing a basal lamina. Although they show a fairly well-developed rough endoplasmic reticulum, Golgi apparatus and immunoreactivity for vimentin, ICC of the deep muscular plexus are probably specialized smooth muscle cells in nature.
Open Access
Neuregulin 1 (NRG1) and its receptors in the enteric nervous system and other parts of the gastrointestinal wall
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2024) Gonkowski, Sławomir
Neuregulin 1 (NRG1) belonging to the transmembrane growth factors family is widespread in living organisms. It acts through ErbB family receptors and first of all takes part in embryogenesis, as well as in developmental, regenerative and adaptive processes occurring in various internal organs and systems. It is known that NRG1 and its receptors are present in various parts of the gastrointestinal (GI) tract. First of all NRG1 and ErbB receptors have been detected in the enteric nervous system (ENS) localized in the wall of the esophagus, stomach and intestine and regulating the majority of the GI tract functions, but also in the mucosal and muscular layers of the GI tract. The NRG1/ErbB pathway is involved in the development and differentiation of the ENS and regulation of the intestinal epithelium functions. Moreover, dysregulation of this pathway results in a wide range of gastrointestinal diseases. However, till now there are no summarizations of previous studies concerning distribution and functions of NRG1 and its receptors in the GI tract. The present review fills this gap.
Open Access
Pore alterations of the endothelial lining of rat fenestrated intestinal capillaries exposed to acute stress
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Aosa, Taishi; Chiba, Seiichi; Kitamura, Hirokazu; Ina, Keisuke; Tatsukawa, Shuji; Moriwaki, Chinatsu; Wei, Huixing; Gotoh, Koro; Masaki, Takayuki; Kakuma, Tetsuya; Shibata, Hirotaka; Fujikura, Yoshihisa
Stress-induced inflammatory responses in the portal system are characterized by elevations in serum concentrations of interleukin-6 (IL-6) and endotoxins such as lipopolysaccharides (LPS). LPS translocation from the intestinal to the capillary lumen occurs via LPS endocytosis by the capillary endothelium. Because the capillary endothelium of the small intestinal submucosa is fenestrated, we determined the role of pore modifications within the fenestrated endothelium in relaying inflammatory stress responses in the portal vein. We evaluated changes in the diameter and density of endothelial pores of the lamina propria of intestinal villi induced by continuous light (CL) exposure for 48 h and the correlation between these changes and serum IL-6 concentration in the portal vein in a rat model. We found significant increases in both the pore diameter and density, accompanied by a significant increase in portal IL-6 concentration; these changes were significantly attenuated by pretreatment with propranolol, a beta adrenergic receptor antagonist. In contrast, intravenous noradrenaline administration mimicked CL-induced modifications of the diameter and density of pores and the elevation of portal vein IL-6 concentration. These findings suggested that stress-induced inflammatory responses in the portal system may be a part of the modifications of the endothelial pores triggered by sympathetic activation.
Embargo
Proteome changes induced by a short, non-cytotoxic exposure to the mycoestrogen zearalenone in the pig intestine
(Elsevier, 2020-07-30) Soler, Laura; Stella, Alexandre; Seva Alcaraz, Juan; Pallarés, Francisco José; Lahjouji, Tarek; Burlet Schiltz, Odile; Oswald, Isabelle P.; Anatomía y Anatomía Patológica Comparadas
Intestinal epithelial homeostasis is regulated by a complex network of signaling pathways. Among them is estrogen signaling, important for the proliferation and differentiation of epithelial cells, immune signaling and metabolism. The mycotoxin zearalenone (ZEN) is an estrogen disruptor naturally found in food and feed. The exposure of the intestine to ZEN has toxic effects including alteration of the immune status and is possibly implicated in carcinogenesis, but the molecular mechanisms linked with these effects are not clear. Our objective was to explore the proteome changes induced by a short, non-cytotoxic exposure to ZEN in the intestine using pig jejunal explants. Our results indicated that ZEN promotes little proteome changes, but significantly related with an induction of ERα signaling and a consequent disruption of highly interrelated signaling cascades, such as NF-κB, ERK1/2, CDX2 and HIF1α. The toxicity of ZEN leads also to an altered immune status characterized by the activation of the chemokine CXCR4/SDF-1 axis and an accumulation of MHC-I proteins. Our results connect the estrogen disrupting activity of ZEN with its intestinal toxic effect, associating the exposure to ZEN with cell-signaling disorders similar to those involved in the onset and progression of diseases such as cancer and chronic inflammatory disorders.
Open Access
Radioautographic studies on radiosulfate incorporation in the digestive organs of mice
(Murcia : F. Hernández, 1999) Nagata, T.; Morita, T.; Kawahara, I.
The sulfate uptake and accumulation in mouse digestive organs were studied by light microscopic radioautography. Two litters of normal ddY mice 30 days after birth, each consisting of 3 animals, were studied. One litter of animals were sacrificed 30 min after the intra eritoneal injections with phosphate buffered NaZ3gO4, and the other litter animals were sacrificed 12 hr after the injections. Then several digestive organs, the parotid gland, the submandibular gland, the sublingual gland, antrum and fundus of the stomach, the duodenum, the jejunum, the ileum, the caecum, the ascending colon and the descending colon were taken out. The tissues were fixed, dehydrated, embedded in epoxy resin, sectioned, picked up onto glass slides, coated with radioautographic emulsion by a dipping method. After the exposure, they were developed, stained with toluidine blue and analyzed by light microscopy. As the results, many silver grains were observed on serous cells of the salivary glands, mucosa and submucosa of the stomach, villous cells and crypt cells of the small intestines and whole mucosa of the large intestines at 30 min after the injection. Then at 12 hr after the injection silver grains were observed on mucous cells of the salivary glands, some of the stomach glands, and mucigen granules of goblet cells in the small intestines and the large intestines. The numbers of silver grains observed in respective organs at 30 min were less than those at 12 hr. From these results, it is concluded that glycoprotein synthesis was demonstrated in several digestive organs by radiosulfate incorporation. In the salivary glands the silver grains were more observed in serous cells at 30 min, while in mucous cells more at 12 hr than 30 min after the injection. In other organs the silver grains were more at 30 min than at 12 hr. These results show the time difference of glycoprotein synthesis in respective organs.

Browsing by Subject "Intestine"

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