In Vitro Observation of the Effect of Intestinal Bacteria on IgA Production by Immunocytes in the Large Intestine: Comparison Between Germ-Free and Conventional Mice

Author(s):  
Tsutomu Yanagibashi ◽  
Akira Hosono ◽  
Masato Tstuda ◽  
Satoshi Hachimura ◽  
Kazuhiro Hirayama ◽  
...  
2012 ◽  
Vol 109 (8) ◽  
pp. 1433-1441 ◽  
Author(s):  
Laura Hanske ◽  
Wolfram Engst ◽  
Gunnar Loh ◽  
Silke Sczesny ◽  
Michael Blaut ◽  
...  

Cyanidin 3-glucoside (C3G) is one of the major dietary anthocyanins implicated in the prevention of chronic diseases. To evaluate the impact of human intestinal bacteria on the fate of C3G in the host, we studied the metabolism of C3G in human microbiota-associated (HMA) rats in comparison with germ-free (GF) rats. Urine and faeces of the rats were analysed for C3G and its metabolites within 48 h after the application of 92 μmol C3G/kg body weight. In addition, we tested the microbial C3G conversion in vitro by incubating C3G with human faecal slurries and selected human gut bacteria. The HMA rats excreted with faeces a three times higher percentage of unconjugated C3G products and a two times higher percentage of conjugated C3G products than the GF rats. These differences were mainly due to the increased excretion of 3,4-dihydroxybenzoic acid, 2,4,6-trihydroxybenzaldehyde and 2,4,6-trihydroxybenzoic acid. Only the urine of HMA rats contained peonidin and 3-hydroxycinnamic acid and the percentage of conjugated C3G products in the urine was decreased compared with the GF rats. Overall, the presence of intestinal microbiota resulted in a 3·7 % recovery of the C3G dose in HMA rats compared with 1·7 % in GF rats. Human intestinal bacteria rapidly degraded C3G in vitro. Most of the C3G products were also found in the absence of bacteria, but at considerably lower levels. The higher concentrations of phenolic acids observed in the presence of intestinal bacteria may contribute to the proposed beneficial health effects of C3G.


2020 ◽  
Author(s):  
Jielong Guo ◽  
Xue Han ◽  
Yilin You ◽  
Weidong Huang ◽  
Zhan Jicheng

Abstract Backgroud: Disruption of the gut microbiota (GM), mainly induced by antibiotic treatments and C-sections, is prevalent during the early lifetime, which can result in lifelong changes in the GM composition and metabolism.Results: The GM of newborn mice was influenced after being subjected to transitory treatment with low-dose penicillin (LDP), resulting in a permanent reduction of intestinal IgA. Germ-free (GF) mice transferred GM from the LDP-treated mice also showed decreased intestinal IgA levels. Similarly, antigens derived from the LDP-treated mice induced lower IgA production during in vitro incubation with small intestinal tissues. Furthermore, a lack of intestinal IgA led to the persistent dysbiosis of mucosal GM, causing metabolic syndrome (MetS) in the LDP-treated mice. The mice lacking intestinal IgA (Pigr-/-) only showed transient alteration in GM after LDP exposure while the long-period metabolism was not influenced. Moreover, gavage with GM from the LDP-free mice or probiotics (partially) restored the GM and intestinal IgA, while improving the MetS in LDP-treated mice.Conclusions: The antibiotics–induced changes of GM in early lifetime permanently dampened the IgA responses to the GM, which lead to the long-term dysbiosis of intestinal mucosal bacteria and MetS.


2009 ◽  
Vol 106 (37) ◽  
pp. 15813-15818 ◽  
Author(s):  
Tanja Petnicki-Ocwieja ◽  
Tomas Hrncir ◽  
Yuen-Joyce Liu ◽  
Amlan Biswas ◽  
Tomas Hudcovic ◽  
...  

Mutations in the Nod2 gene are among the strongest genetic risk factors in the pathogenesis of ileal Crohn's disease, but the exact contributions of Nod2 to intestinal mucosal homeostasis are not understood. Here we show that Nod2 plays an essential role in controlling commensal bacterial flora in the intestine. Analysis of intestinal bacteria from the terminal ilea of Nod2-deficient mice showed that they harbor an increased load of commensal resident bacteria. Furthermore, Nod2-deficient mice had a diminished ability to prevent intestinal colonization of pathogenic bacteria. In vitro, intestinal crypts isolated from terminal ilea of Nod2-deficient mice were unable to kill bacteria effectively, suggesting an important role of Nod2 signaling in crypt function. Interestingly, the expression of Nod2 is dependent on the presence of commensal bacteria, because mice re-derived into germ-free conditions expressed significantly less Nod2 in their terminal ilea, and complementation of commensal bacteria into germ-free mice induced Nod2 expression. Therefore, Nod2 and intestinal commensal bacterial flora maintain a balance by regulating each other through a feedback mechanism. Dysfunction of Nod2 results in a break-down of this homeostasis.


Antibiotics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 180
Author(s):  
Kouki Shimizu ◽  
Issei Seiki ◽  
Yoshiyuki Goto ◽  
Takeshi Murata

The intestinal pH can greatly influence the stability and absorption of oral drugs. Therefore, knowledge of intestinal pH is necessary to understand the conditions for drug delivery. This has previously been measured in humans and rats. However, information on intestinal pH in mice is insufficient despite these animals being used often in preclinical testing. In this study, 72 female ICR mice housed in SPF (specific pathogen-free) conditions were separated into nine groups to determine the intestinal pH under conditions that might cause pH fluctuations, including high-protein diet, ageing, proton pump inhibitor (PPI) treatment, several antibiotic treatment regimens and germ-free mice. pH was measured in samples collected from the ileum, cecum and colon, and compared to control animals. An electrode, 3 mm in diameter, enabled accurate pH measurements with a small amount of gastrointestinal content. Consequently, the pH values in the cecum and colon were increased by high-protein diet, and the pH in the ileum was decreased by PPI. Drastic alkalization was induced by antibiotics, especially in the cecum and colon. The alkalized pH values in germ-free mice suggested that the reduction in the intestinal bacteria caused by antibiotics led to alkalization. Alkalization of the intestinal pH caused by antibiotic treatment was verified in mice. We need further investigations in clinical settings to check whether the same phenomena occur in patients.


2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S34-S35
Author(s):  
Terrence Roh ◽  
Ying Chen ◽  
Harry Paul ◽  
Chengchen Guo ◽  
David Kaplan

Abstract An in vitro model of intestine epithelium with an immune compartment was bioengineered to mimic immunologic responses seen in inflammatory bowel disease [1]. While aspects of intestinal immunity can be modeled in transwells and 2D culture systems, 3D tissue models improve physiological relevance by providing a 3D substrate which enable migration of macrophages towards the epithelium. An intestinal epithelium comprised of non-transformed human colon organoid cells and a subepithelial layer laden with monocyte-derived macrophages was bioengineered to mimic native intestinal mucosa cell organization using spongy silk scaffolds. Confluent epithelial monolayers with microvilli, a mucus layer, and infiltration of macrophages to the basal side of the epithelium were observed. Inflammation, induced by E. coli O111:B4 lipopolysaccharide and interferon γ resulted in morphology changes to the epithelium, resulting in ball-like structures, decreased epithelial coverage, and migration of macrophages to the epithelium. Analysis of cytokines present in the inflamed tissue model demonstrated significantly upregulated secretion of pro-inflammatory cytokines associated with active inflammatory bowel disease, including CXCL10, IL-1β, IL-6, MCP-2, and MIP-1β. The macrophage layer enhanced epithelial and biochemical responses to inflammatory stimuli, and this new tissue system may be useful to study and develop potential therapies for inflammatory bowel disease. References: 6 Roh, T.T., et al., 3D bioengineered tissue model of the large intestine to study inflammatory bowel disease. Biomaterials, 2019: p. 119517. 7 In, J., et al., Enterohemorrhagic Escherichia coli reduce mucus and intermicrovillar bridges in human stem cell-derived colonoids. Cellular and molecular gastroenterology and hepatology, 2015. 2(1): p. 48–62.e3. 8 Chen, Y., et al., In vitro enteroid-derived three-dimensional tissue model of human small intestinal epithelium with innate immune responses. PLoS ONE, 2017. 12(11): p. e0187880. Colonoid and macrophage cultivation scheme in the 3D bilayer system. (A) Human monocytes were isolated from whole blood and human colonoids from large intestine biopsies were cultured according to established protocols [2]. (B) Cell suspensions of colonoids were seeded on the film surface on the inner silk scaffold and monocyte-derived macrophages were seeded throughout the porous outer silk scaffold using established protocols [3]. (C) The model is cultured for 3 weeks total with 2 weeks in High WNT media and 1 week in differentiation media based on established protocol. Colonoids are present in the model throughout the 3 week culture time. 2 sets of macrophages are added with the first set added after the first week of culture and the second set replacing the first set after the second week.


2010 ◽  
Vol 133 (1-3) ◽  
pp. 161-163 ◽  
Author(s):  
N. Sauer ◽  
E. Bauer ◽  
W. Vahjen ◽  
J. Zentek ◽  
R. Mosenthin
Keyword(s):  

2003 ◽  
Vol 73 (2) ◽  
pp. 120-126 ◽  
Author(s):  
Cassidy

Interest in the physiological role of bioactive compounds present in plants has increased dramatically over the last decade. Of particular interest in relation to human health are the class of compounds known as the phytoestrogens, which embody several groups of non-steroidal oestrogens including isoflavones & lignans that are widely distributed within the plant kingdom. Data from animal and in vitro studies provide plausible mechanisms to explain how phytoestrogens may influence hormone dependent states, but although the clinical application of diets rich in these oestrogen mimics is in its infancy, data from preliminary studies suggest potential beneficial effects of importance to health. Phytoestrogens are strikingly similar in chemical structure to the mammalian oestrogen, oestradiol, and bind to oestrogen receptors (ER) with a preference for the more recently described ERb. This suggests that these compounds may exert tissue specific effects. Numerous other biological effects independent of the ER (e.g. antioxidant capacity, antiproliferative and antiangiogenic effects) have been ascribed to these compounds. Whether phytoestrogens have any biological activity in humans, either hormonal or non hormonal is a contentious issue and there is currently a paucity of data on human exposure. Much of the available data on the absorption and metabolism of dietary phytoestrogens is of a qualitative nature; it is known that dietary phytoestrogens are metabolised by intestinal bacteria, absorbed, conjugated in the liver, circulated in plasma and excreted in urine. Recent studies have addressed quantitatively what happens to isoflavones following ingestion – with pure compound and stable isotope data to compliment recent pharmacokinetic data for soy foods. The limited studies conducted so far in humans clearly confirm that soya isoflavones can exert hormonal effects. These effects may be of benefit in the prevention of many of the common diseases observed in Western populations (such as breast cancer, prostate cancer, menopausal symptoms, osteoporosis) where the diet is typically devoid of these biologically active naturally occurring compounds. However since biological effects are dependent on many factors including dose, duration of use, protein binding affinity, individual metabolism and intrinsic oestrogenic state, further clinical studies are necessary to determine the potential health effects of these compounds in specific population groups. However we currently know little about age related differences in exposure to these compounds and there are few guidelines on optimal dose for specific health outcomes.


2021 ◽  
Vol 2 (1) ◽  
pp. 18-24
Author(s):  
Didiek Hardiyanto Soegiantoro ◽  
Gregory Hope Soegiantoro ◽  
Intan Selvyanti Waruwu ◽  
Yanti Octavia Theressia

The use of turmeric rhizome to treat diarrhea is written in the original Indonesian medicinal manuscript. Diarrhea disease is still a public health problem in Indonesia, because of its high morbidity and mortality. The morbidity survey conducted by Indonesian Ministry of Health shows an increasing incidence trend. One of the causes of diarrhea is an uncontrolled increase in the number of intestinal bacteria and infection by intestinal pathogenic bacteria. This study aims to determine the effect of the turmeric rhizome preparation process, both traditionally and by extraction method by maceration and soxhletation on antibacterial activity, especially intestinal bacteria, so that it can be applied by the traditional medicine industry as well as traditional herbal medicine sellers (“jamu gendong”). The research method used was to test the antibacterial activity of fresh turmeric juice, pre-dried turmeric juice, turmeric extract by maceration using 95% ethanol, and turmeric extract by soxhletation at 100°C using 95% ethanol. The intestinal bacteria used in this study were Escherichia coli, Yersinia enterolitica, Vibrio nonagglutinable, and Shigella flexneri. The results of this study indicate that the treatment process using the traditional method, both fresh turmeric juice and pre-dried turmeric juice, does not show any antibacterial activity. Turmeric extract by maceration showed antibacterial activity against all bacterias and the greatest against Vibrio nonagglutinable bacteria. Turmeric extract by soxhletation showed antibacterial activity against all bacterias and the greatest against Vibrio nonagglutinable bacteria. The conclusion of this study is that the most appropriate method used to process turmeric rhizome as a medicine for diarrhea caused by bacteria is the extraction method by maceration or soxhletation. The greatest antibacterial effect is against the Vibrio nonagglutinable bacteria.


2015 ◽  
Vol 82 (1) ◽  
pp. 289-296 ◽  
Author(s):  
Varvara Tsilia ◽  
Frederiek-Maarten Kerckhof ◽  
Andreja Rajkovic ◽  
Marc Heyndrickx ◽  
Tom Van de Wiele

ABSTRACTAdhesion to the intestinal epithelium could constitute an essential mechanism ofBacillus cereuspathogenesis. However, the enterocytes are protected by mucus, a secretion composed mainly of mucin glycoproteins. These may serve as nutrients and sites of adhesion for intestinal bacteria. In this study, the food poisoning bacteriumB. cereusNVH 0500/00 was exposedin vitroto gastrointestinal hurdles prior to evaluation of its attachment to mucin microcosms and its ability to produce nonhemolytic enterotoxin (Nhe). The persistence of mucin-adherentB. cereusafter simulated gut emptying was determined using a mucin adhesion assay. The stability of Nhe toward bile and pancreatin (intestinal components) in the presence of mucin agar was also investigated.B. cereuscould grow and simultaneously adhere to mucin duringin vitroileal incubation, despite the adverse effect of prior exposure to a low pH or intestinal components. The final concentration ofB. cereusin the simulated lumen at 8 h of incubation was 6.62 ± 0.87 log CFU ml−1. At that point, the percentage of adhesion was approximately 6%. No enterotoxin was detected in the ileum, due to either insufficient bacterial concentrations or Nhe degradation. Nevertheless, mucin appears to retainB. cereusand to supply it to the small intestine after simulated gut emptying. Additionally, mucin may play a role in the protection of enterotoxins from degradation by intestinal components.


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