| 21. |
- Fåk, Frida, et al.
(författare)
-
Microbial manipulation of the rat dam changes bacterial colonization and alters properties of the gut in her offspring.
- 2008
-
Ingår i: American Journal of Physiology: Gastrointestinal and Liver Physiology. - : American Physiological Society. - 1522-1547 .- 0193-1857. ; 294, s. 148-154
-
Tidskriftsartikel (refereegranskat)abstract
- The impact of an altered bacterial colonization on gut development has not been thoroughly studied, despite the increased risk of certain diseases with a disturbed microbiota after birth. This study was conducted to determine the effect of microbial manipulation, i.e. antibiotic treatment or Escherichia coli (E. coli) exposure, of the dam on bacterial colonization and gut development in the offspring. Pregnant rats were administered either broad-spectrum antibiotics three days prior to parturition, or live non-pathogenic E. coli CCUG 29300T one week before parturition and up to 14 days of lactation in the drinking water. Caecal bacterial levels, gut growth, intestinal permeability, digestive enzyme levels and intestinal inflammation were studied in two-week old rats. Pups from dams that were antibiotic-treated had higher densities of Enterobacteriaceae which correlated with a decreased stomach growth and function, lower pancreatic protein levels, higher intestinal permeability and increased plasma levels of the acute phase protein, haptoglobin, compared with pups from untreated mothers. Exposure of pregnant/lactating mothers to E. coli CCUG 29300T, also resulting in increased Enterobacteriaceae levels, gave in the offspring similar results on the stomach and an increased small intestinal growth as compared to the control pups. Furthermore, E. coli pups showed increased mucosal disaccharidase activities, increased liver, spleen and adrenal weights, as well as increased plasma concentrations of haptoglobin. These findings indicate that disturbing the normal bacterial colonization after birth, by increasing the densities of caecal Enterobacteriaceae, appear to have lasting effects on the postnatal microflora which affects gut growth and function.
|
|
| 22. |
|
|
| 23. |
- Goncharova, Kateryna, et al.
(författare)
-
Importance of neonatal immunoglobulin transfer for hippocampal development and behaviour in the newborn pig
- 2017
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 12:6
-
Tidskriftsartikel (refereegranskat)abstract
- Neurological disorders are among the main clinical problems affecting preterm children and often result in the development of communication and learning disabilities later in life. Several factors are of importance for brain development, however the role of immunoglobulins (passive immunity transfer) has not yet been investigated. Piglets are born agammaglobulinemic, as a result of the lack of transfer of maternal immunoglobulins in utero, thus, they serve as an ideal model to mimic the condition of immunoglobulin deficiency in preterm infants. Thirty six, unsuckled newborn piglets were fed an infant formula or colostrum and supplemented orally or intravenously with either species-specific or foreign immunoglobulin and then compared to both newborn and sow-reared piglets. Two days after the piglets were born behavioural tests (novel recognition and olfactory discrimination of conspecifics scent) were performed, after which the piglets were sacrificed and blood, cerebrospinal fluid and hippocampi samples were collected for analyses. Both parameters of neuronal plasticity (neuronal maturation and synapse-associated proteins) and behavioural test parameters appeared to be improved by the appearance of species-specific porcine immunoglulin in the circulation and cerebrospinal fluid of the piglets. In conclusion, we postulate possible positive clinical effects following intravenous infusion of human immunoglobulin in terms of neuronal plasticity and cognitive function in preterm infants born with low blood immunoglobulin levels.
|
|
| 24. |
|
|
| 25. |
- Keita, Åsa, 1973-
(författare)
-
Barrier function of the Follicle-Associated Epithelium in Stress and Crohn's disease
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Crohns sjukdom är en kronisk inflammatorisk tarmsjukdom av okänd orsak. Det tidigaste tecknet på Crohns sjukdom är mikroskopiska sår i det s.k. follikelassocierade epitelet (FAE) som täcker ansamlingar av immunceller i tarmen. FAE är specialiserat för att fånga innehåll från tarmen och transportera det till underliggande immunvävnad. Denna funktion är viktig för att inducera skyddande immunsvar, men den utgör också en ingångsväg för sjukdomsalstrande bakterier. Crohns sjukdom är associerat med ett kraftigt ökat immunsvar mot bakterier, och sjukdomsförloppet kan ändras av stress.Det övergripande syftet med avhandlingen var att studera effekterna av stress på FAE samt att undersöka rollen av FAE vid utvecklingen av tarminflammation, särskilt vid Crohns sjukdom.Inledningsvis studerades effekterna av psykologisk stress på FAE. Stressade råttor uppvisade ökad genomsläpplighet av bakterier efter stress, och passagen var högre i FAE än i vanligt epitel. Efterföljande experiment visade att stressförändringarna i slemhinnan regleras via kortikotropinfrisättande hormon och mastceller. Vidare visade det sig att vasoaktiv intestinal peptid kunde efterlikna stressens effekter på genomsläppligheten, och att detta kunde förhindras genom att blockera mastcellerna.Studier av tunntarmsslemhinna från patienter med icke-inflammatorisk tarmsjukdom och friska kontroller visade en högre passage av bakterier i FAE än i vanligt epitel. Hos patienter med Crohns sjukdom var bakteriepassagen genom FAE betydligt ökad jämfört med kontroller.Resultaten från detta avhandlingsarbete visar att stress kan förändra upptaget av bakterier från tarmen via FAE, med mekanismer som innefattar kortikotropinfrisättande hormon och mastceller. Detta har gett nya kunskaper kring regleringen av slemhinnebarriären. Vidare presenterar denna avhandling nya insikter i sjukdomsuppkomsten vid Crohns sjukdom genom att påvisa en tidigare okänd defekt i barriärfunktionen i FAE.
|
|
| 26. |
- Kruszewska, Danuta, et al.
(författare)
-
Enteral crude red kidney bean (Phaseolus vulgaris) lectin--phytohemagglutinin--induces maturational changes in the enterocyte membrane proteins of suckling rats.
- 2003
-
Ingår i: Biology of the Neonate. - : S. Karger AG. - 1421-9727. ; 84:2, s. 152-158
-
Tidskriftsartikel (refereegranskat)abstract
- This study aimed to investigate the effect of enterally administered crude red kidney bean (Phaseolus vulgaris) lectin, PHA, on the expression of brush-border membrane vesicle (BBMV) proteins, in particular Na+/H+ exchangers (NHEs), in the small intestine of suckling rats. Gavage of PHA to 14-day-old rats for 3 days resulted in altered protein/glycoprotein patterns as analyzed by SDS-PAGE. Immunoblots demonstrated the appearance of two 71- and 27-kD protein bands indicative for NHE3 - one of the NHE isoforms - and PHA, respectively. PHA treatment also resulted in an augmented uptake of 22Na+ by the BBMV indicating an increase in NHE activity. Overall, the data suggests that enteral PHA exposure may induce maturational changes in enterocyte membrane proteins in young rats. In view of these findings, an investigation into the addition of PHA to infant formulas and weaning diets is warranted.
|
|
| 27. |
- Köhnke, Rickard, et al.
(författare)
-
Feeding appetite suppressing thylakoids to pigs alters pancreatic lipase/colipase secretion
- 2010
-
Ingår i: Livestock Science. - : Elsevier BV. - 1871-1413. ; 134:1-3, s. 68-71
-
Konferensbidrag (refereegranskat)abstract
- The mechanism for a new appetite suppressor named thylakoids (membrane proteins derived from spinach leaves) was examined in vivo in pigs. Thylakoids inhibit the lipase/colipase hydrolysis of triacylglycerols (TG) in vitro and suppress food intake, decrease body weight gain and raise the circulating satiety hormone cholecystokinin (CCK) in rats but its mechanism in vivo remains unclear. We hypothesized that a thylakoid-enriched diet prolongs intestinal digestion of food and therefore promote satiety signaling. Five pigs were surgically prepared with a fistula in the duodenum for collection of digesta and with two catheters, one in v. jugularis and one in v. porta, for blood collection. After 1 week of recovery and an overnight fast the pigs were fed a high-fat diet with and without supplementation with thylakoids. Duodenal content and blood samples were taken before and 15, 30, 60, 120, 240 and 360 min after feeding. Pancreatic lipase and colipase enzymes were measured in duodenal digesta. Blood samples were analyzed for the satiety hormone CCK as well as insulin and glucose. We found that pancreatic lipase/colipase level increased and stayed elevated for a longer time in the duodenum in the pigs receiving thylakoids compared to the control. CCK levels were unchanged. Insulin levels were significantly reduced by the thylakoid treatment without any change in blood glucose. In conclusion, thylakoids increased lipase/colipase secretion. The mechanism for this secretion appears not to be related to CCK and may be an effect of vagal activation. Thylakoids gave reduced insulin levels without any change in glucose levels. (C) 2010 Published by Elsevier B.V.
|
|
| 28. |
- Lavasani, Shahram, et al.
(författare)
-
A novel probiotic mixture exerts a therapeutic effect on experimental autoimmune encephalomyelitis mediated by IL-10 producing regulatory T cells.
- 2010
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 5:2
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system (CNS). One potential therapeutic strategy for MS is to induce regulatory cells that mediate immunological tolerance. Probiotics, including lactobacilli, are known to induce immunomodulatory activity with promising effects in inflammatory diseases. We tested the potential of various strains of lactobacilli for suppression of experimental autoimmune encephalomyelitis (EAE), an animal model of MS. METHODOLOGY/PRINCIPAL FINDINGS: The preventive effects of five daily-administered strains of lactobacilli were investigated in mice developing EAE. After a primary screening, three Lactobacillus strains, L. paracasei DSM 13434, L. plantarum DSM 15312 and DSM 15313 that reduced inflammation in CNS and autoreactive T cell responses were chosen. L. paracasei and L. plantarum DSM 15312 induced CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) in mesenteric lymph nodes (MLNs) and enhanced production of serum TGF-beta1, while L. plantarum DSM 15313 increased serum IL-27 levels. Further screening of the chosen strains showed that each monostrain probiotic failed to be therapeutic in diseased mice, while a mixture of the three lactobacilli strains suppressed the progression and reversed the clinical and histological signs of EAE. The suppressive activity correlated with attenuation of pro-inflammatory Th1 and Th17 cytokines followed by IL-10 induction in MLNs, spleen and blood. Additional adoptive transfer studies demonstrated that IL-10 producing CD4(+)CD25(+) Tregs are involved in the suppressive effect induced by the lactobacilli mixture. CONCLUSIONS/SIGNIFICANCE: Our data provide evidence showing that the therapeutic effect of the chosen mixture of probiotic lactobacilli was associated with induction of transferable tolerogenic Tregs in MLNs, but also in the periphery and the CNS, mediated through an IL-10-dependent mechanism. Our findings indicate a therapeutic potential of oral administration of a combination of probiotics and provide a more complete understanding of the host-commensal interactions that contribute to beneficial effects in autoimmune diseases.
|
|
| 29. |
- Linderoth, Ann, et al.
(författare)
-
Binding and the effect of the red kidney bean lectin, phytohaemagglutinin, in the gastrointestinal tract of suckling rats
- 2006
-
Ingår i: British Journal of Nutrition. - 1475-2662. ; 95:1, s. 105-115
-
Tidskriftsartikel (refereegranskat)abstract
- Enteral exposure of suckling rats to phytohaemagglutinin (PHA) has been shown to induce growth and precocious functional maturation of the gastrointestinal tract. The aim of the present study was to explore the mechanism of this action. Suckling rats, 14 d old, were fed a single dose of PHA (0.05 mg/g body weight) or saline. The binding of PHA to the gut epithelium and its effect on the morphology and functional properties of the gut and pancreas were studied up to 3 d after treatment. Initially, at 1-24 h, the PHA bound along the gut mucosal lining, resulting in disturbed gut morphology with villi shortening and rapid decreases in disaccharidase activities and macromolecular absorption capacity. During a later phase, between 1 and 3 d, the PHA binding had declined, and an uptake by enterocytes was observed. An increase in crypt cell proliferation and gut growth became evident during this period, together with a functional maturation, as indicated by increases in disaccharidase (maltase and sucrase) activities and the low macromolecular absorption capacity. Pancreas growth also increased, as did its content of digestive enzymes. We conclude that enteral exposure to PHA in suckling rats temporarily causes mucosal disarrangement and functional impediment of the gut, which may be explained by binding to and disruption of the gut mucosa and a two-fold increase in the plasma corticosterone concentration. These findings may lead to a better understanding of the role of diet in gastrointestinal maturation and may constitute a basis for the treatment of mammals having an immature gut.
|
|
| 30. |
- Linderoth, Ann, et al.
(författare)
-
Enterally but not parenterally administered Phaseolus vulgaris lectin induces growth and precocious maturation of the gut in suckling rats
- 2006
-
Ingår i: Biology of the Neonate. - : S. Karger AG. - 1421-9727. ; 89:1-3, s. 60-68
-
Tidskriftsartikel (refereegranskat)abstract
- Background: The lectin, phytohemagglutinin (PHA) has been shown to induce growth and functional maturation of the gastrointestinal (GI) tract in suckling rats. Objectives: To investigate the effect of the administration route, and whether enteral exposure to PHA was necessary to induce functional maturation. Methods: Fourteen-day-old rats were daily administered PHA via orogastric feeding (0.05 mg PHA/g BW) or via subcutaneous injection (0.05 or 0.005 mg PHA/g BW) for 3 days, while the controls received saline orogastrically. At 17 days of age, organ weight, intestinal and pancreatic function, and plasma corticosterone levels were analyzed. Moreover, 14-days old pups receiving a single dose of PHA, enterally or parenterally, were sacrificed after 12 h and examined for organ PHA binding using immunohistochemistry. Results: Enteral PHA exposure resulted in PHA binding in the epithelial lining of the small intestine, increased gastrointestinal growth, reduced intestinal macromolecular absorption, altered the disaccharidase expression towards an adult-like pattern, and increased the pancreatic protein and trypsin contents. In contrast, parenteral PHA exposure (high dose) resulted in PHA-binding in extra-intestinal organs, increased liver and spleen weight, and decreased thymus weight. Moreover, the intestinal maltase activity increased moderately, and the transfer of BSA to blood plasma was partially reduced. Both PHA treatments led to elevated plasma corticosterone levels. Conclusion: These results demonstrated that enteral exposure to PHA was necessary to induce the precocious maturation of the GI tract and the pancreas, while parenteral administration affects the extra-intestinal organs. Furthermore, the enteral effects were probably not mediated via a corticosteroid dependent pathway.
|
|
