scholarly journals Lack of response of INT-407 cells to the presence of non-culturableCampylobacter jejuni

2007 ◽  
Vol 136 (10) ◽  
pp. 1401-1406 ◽  
Author(s):  
L. VERHOEFF-BAKKENES ◽  
W. C. HAZELEGER ◽  
M. H. ZWIETERING ◽  
R. De JONGE
Keyword(s):  
Campylobacter Jejuni ◽  
Cell Layer ◽  
Potential Effect ◽  
Outer Cell ◽  
Culturable Bacteria ◽  
Small Intestines ◽  
Outer Cell Layer ◽  
Number Of Bacteria

SUMMARYMany contradictory articles on the infectivity of non-culturableCampylobacter jejunican be found. We studied the effect of non-culturableC. jejuniin anin vitroassay. To prevent the potential effect of a few culturable bacteria in the non-culturable suspension, INT-407 cells, which mimic the outer cell layer in the small intestines, were exposed to culturableC. jejunisuspensions with or without non-culturableC. jejuni. The number of bacteria adhering to and/or invading INT-407 cells and the IL-8 secretion were measured. No differences were found between bacterial suspensions with or without non-culturableC. jejuniadded. These findings show that non-culturableC. jejunido not adhere to or invade INT-407 cells and do not induce an immune response. As previous studies showed a correlation between the usedin vitroassays and the effectin vivo, our study strongly suggests that culturability is a good indicator of the risk forC. jejuniinfection.

scholarly journals The Effects of Conjugated Linoleic Acids on Cancer

Processes ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 454 ◽  
Author(s):  
Marko Dachev ◽  
Jana Bryndová ◽  
Milan Jakubek ◽  
Zdeněk Moučka ◽  
Marian Urban
Keyword(s):  
Potential Effect ◽  
Conjugated Linoleic Acids ◽  
Carcinogenic Activity ◽  
Beneficial Effects ◽  
True Value ◽  
Ruminant Animals ◽  
Anti Oxidant ◽  
Cancer Agent

Conjugated linoleic acids (CLA) are distinctive polyunsaturated fatty acids. They are present in food produced by ruminant animals and they are accumulated in seeds of certain plants. These naturally occurring substances have demonstrated to have anti-carcinogenic activity. Their potential effect to inhibit cancer has been shown in vivo and in vitro studies. In this review, we present the multiple effects of CLA isomers on cancer development such as anti-tumor efficiency, anti-mutagenic and anti-oxidant activity. Although the majority of the studies in vivo and in vitro summarized in this review have demonstrated beneficial effects of CLA on the proliferation and apoptosis of tumor cells, further experimental work is needed to estimate the true value of CLA as a real anti-cancer agent.

scholarly journals Effects of Bacterial CLPB Protein Fragments on Food Intake and PYY Secretion

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2223
Author(s):  
Manon Dominique ◽  
Nicolas Lucas ◽  
Romain Legrand ◽  
Illona-Marie Bouleté ◽  
Christine Bôle-Feysot ◽  
...  
Keyword(s):  
Food Intake ◽  
Peptide Yy ◽  
Molecular Mimicry ◽  
Potential Effect ◽  
In Vivo Studies ◽  
Sprague Dawley ◽  
E Coli ◽  
In Vivo Effects

CLPB (Caseinolytic peptidase B) protein is a conformational mimetic of α-MSH, an anorectic hormone. Previous in vivo studies have already shown the potential effect of CLPB protein on food intake and on the production of peptide YY (PYY) by injection of E. coli wild type (WT) or E. coli ΔClpB. However, until now, no study has shown its direct effect on food intake. Furthermore, this protein can fragment naturally. Therefore, the aim of this study was (i) to evaluate the in vitro effects of CLPB fragments on PYY production; and (ii) to test the in vivo effects of a CLPB fragment sharing molecular mimicry with α-MSH (CLPB25) compared to natural fragments of the CLPB protein (CLPB96). To do that, a primary culture of intestinal mucosal cells from male Sprague–Dawley rats was incubated with proteins extracted from E. coli WT and ΔCLPB after fragmentation with trypsin or after a heat treatment of the CLPB protein. PYY secretion was measured by ELISA. CLPB fragments were analyzed by Western Blot using anti-α-MSH antibodies. In vivo effects of the CLPB protein on food intake were evaluated by intraperitoneal injections in male C57Bl/6 and ob/ob mice using the BioDAQ® system. The natural CLPB96 fragmentation increased PYY production in vitro and significantly decreased cumulative food intake from 2 h in C57Bl/6 and ob/ob mice on the contrary to CLPB25. Therefore, the anorexigenic effect of CLPB is likely the consequence of enhanced PYY secretion.

scholarly journals The glycosyltransferase ST3GAL2 is regulated by miR-615-3p in the intestinal tract of Campylobacter jejuni infected mice

Gut Pathogens ◽  
2021 ◽  
Vol 13 (1) ◽  
Author(s):  
De Xi ◽  
Lukas Hofmann ◽  
Thomas Alter ◽  
Ralf Einspanier ◽  
Stefan Bereswill ◽  
...  
Keyword(s):  
Campylobacter Jejuni ◽  
Regulatory Networks ◽  
In Silico Analysis ◽  
Luciferase Reporter ◽  
Colonic Tissue ◽  
Tissue Samples ◽  
Vitro Model ◽  
Pathway Analyses

Abstract Background Campylobacter jejuni (C. jejuni) infections are of increasing importance worldwide. As a typical mucosal pathogen, the interaction of C. jejuni with mucins is a prominent step in the colonisation of mucosal surfaces. Despite recent advances in understanding the interaction between bacterial pathogens and host mucins, the mechanisms of mucin glycosylation during intestinal C. jejuni infection remain largely unclear. This prompted us to identify relevant regulatory networks that are concerted by miRNAs and could play a role in the mucin modification and interaction. Results We firstly used a human intestinal in vitro model, in which we observed altered transcription of MUC2 and TFF3 upon C. jejuni NCTC 11168 infection. Using a combined approach consisting of in silico analysis together with in vitro expression analysis, we identified the conserved miRNAs miR-125a-5p and miR-615-3p associated with MUC2 and TFF3. Further pathway analyses showed that both miRNAs appear to regulate glycosyltransferases, which are related to the KEGG pathway ‘Mucin type O-glycan biosynthesis’. To validate the proposed interactions, we applied an in vivo approach utilising a well-established secondary abiotic IL-10−/− mouse model for infection with C. jejuni 81-176. In colonic tissue samples, we confirmed infection-dependent aberrant transcription of MUC2 and TFF3. Moreover, two predicted glycosyltransferases, the sialyltransferases ST3GAL1 and ST3GAL2, exhibited inversely correlated transcriptional levels compared to the expression of the identified miRNAs miR-125a-5p and miR-615-3p, respectively. In this study, we mainly focused on the interaction between miR-615-3p and ST3GAL2 and were able to demonstrate their molecular interaction using luciferase reporter assays and RNAi. Detection of ST3GAL2 in murine colonic tissue by immunofluorescence demonstrated reduced intensity after C. jejuni 81-176 infection and was thus consistent with the observations made above. Conclusions We report here for the first time the regulation of glycosyltransferases by miRNAs during murine infection with C. jejuni 81-176. Our data suggest that mucin type O-glycan biosynthesis is concerted by the interplay of miRNAs and glycosyltransferases, which could determine the shape of intestinal glycosylated proteins during infection.

scholarly journals Rotavirus Infection Is Not Associated with Small Intestinal Fluid Secretion in the Adult Mouse

2006 ◽  
Vol 80 (22) ◽  
pp. 11355-11361 ◽  
Author(s):  
Shirin Kordasti ◽  
Claudia Istrate ◽  
Mahanez Banasaz ◽  
Martin Rottenberg ◽  
Henrik Sjövall ◽  
...  
Keyword(s):  
Fluid Secretion ◽  
Chloride Secretion ◽  
Potential Difference ◽  
Pathophysiological Mechanism ◽  
Rotavirus Infection ◽  
In Vivo Experiments ◽  
Adult Mice ◽  
Small Intestines

ABSTRACT In contrast to humans, adult but not infant small animals are resistant to rotavirus diarrhea. The pathophysiological mechanism behind this age-restricted diarrhea is currently unresolved, and this question was investigated by studying the secretory state of the small intestines of adult mice infected with rotavirus. Immunohistochemistry and histological examinations revealed that rotavirus (strain EDIM) infects all parts of the small intestines of adult mice, with significant numbers of infected cells in the ilea at 2 and 4 days postinfection. Furthermore, quantitative PCR revealed that 100-fold more viral RNA was produced in the ilea than in the jejuna or duodena of adult mice. In vitro perfusion experiments of the small intestine did not reveal any significant changes in net fluid secretion among mice infected for 3 days or 4 days or in those that were noninfected (37 ± 9 μl · h−1 · cm−1, 22 ± 13 μl · h−1 · cm−1, and 33 ± 6 μl · h−1 · cm−1, respectively) or in transmucosal potential difference (4.0 ± 0.3 mV versus 3.9 ± 0.4 mV), a marker for active chloride secretion, between control and rotavirus-infected mice. In vivo experiments also did not show any differences in potential difference between uninfected and infected small intestines. Furthermore, no significant differences in weight between infected and uninfected small intestines were found, nor were any differences in fecal output observed between infected and control mice. Altogether, these data suggest that rotavirus infection is not sufficient to stimulate chloride and water secretion from the small intestines of adult mice.

Embryonic development of the heart

Development ◽  
1969 ◽  
Vol 22 (3) ◽  
pp. 333-348
Author(s):  
Francis J. Manasek
Keyword(s):  
Cell Layer ◽  
Embryonic Heart ◽  
Outer Cell ◽  
Chick Embryos ◽  
Myocardial Wall ◽  
Undifferentiated Cells ◽  
Epicardial Layer ◽  
Outer Cell Layer ◽  
Heart Wall

The mature heart may be thought of as consisting of three layers, endocardium, myocardium, and an outer investing tissue called the epicardium. During early formation of the tubular heart of chick embryos, at about the 8-somite stage, two tissue layers become clearly discernible with the light microscope: the endocardium and the developing myocardial wall. The outer epicardial layer does not appear until later in development. It is generally accepted that embryonic heart wall or ‘epimyocardium’ is composed of muscle and undifferentiated cells. As its name implies, the epimyocardium is thought to give rise to myocardium and epicardium. Kurkiewicz (1909) suggested that the epicardium was not an epimyocardial derivative but rather is formed from cells originating in the sinus venosus region, which migrate over the surface of the heart. Nevertheless, it has become generally accepted that the outer cell layer of the embryonic heart wall differentiates in situ to give rise to the definitive visceral epicardium (Patten, 1953).

Sirtuin-dependent reversible lysine acetylation controls the activity of acetyl-Coenzyme A synthetase in Campylobacter jejuni

2021 ◽  
Author(s):  
Victoria L. Jeter ◽  
Jorge C. Escalante-Semerena
Keyword(s):  
Campylobacter Jejuni ◽  
Posttranslational Modifications ◽  
Active Site ◽  
Protein Function ◽  
Metabolic Enzyme ◽  
Lysine Acetylation ◽  
Class Iii ◽  
Acetyl Coa

Posttranslational modifications are mechanisms for rapid control of protein function used by cells from all domains of life. Acetylation of the epsilon amino group ( N ε ) of an active-site lysine of the AMP-forming acetyl-CoA synthetase (Acs) enzyme is the paradigm for the posttranslational control of the activity of metabolic enzymes. In bacteria, the alluded active-site lysine of Acs enzymes can be modified by a number of different GCN5-type N -acetyltransferases (GNATs). Acs activity is lost as a result of acetylation, and restored by deacetylation. Using a heterologous host, we show that Campylobacter jejuni NCTC11168 synthesizes enzymes that control Acs function by reversible lysine acetylation (RLA). This work validates the function of gene products encoded by the cj1537c , cj1715, and cj1050c loci, namely the AMP-forming acetate:CoA ligase ( Cj Acs), a type IV GCN5-type lysine acetyltransferase (GNAT, hereafter Cj LatA), and a NAD + -dependent (class III) sirtuin deacylase ( Cj CobB), respectively. To our knowledge, these are the first in vivo and in vitro data on C. jejuni enzymes that control the activity of Cj Acs. IMPORTANCE This work is important because it provides the experimental evidence needed to support the assignment of function to three key enzymes, two of which control the reversible posttranslational modification of an active-site lysyl residue of the central metabolic enzyme acetyl-CoA synthetase ( Cj Acs). We can now generate Campylobacter jejuni mutant strains defective in these functions, so we can establish the conditions in which this mode of regulation of Cj Acs is triggered in this bacterium. Such knowledge may provide new therapeutic strategies for the control of this pathogen.

scholarly journals Local Immune Responses to Chlamydia pneumoniae in the Lungs of BALB/c Mice during Primary Infection and Reinfection

1998 ◽  
Vol 66 (11) ◽  
pp. 5113-5118 ◽  
Author(s):  
Jenni M. Penttilä ◽  
Marjukka Anttila ◽  
Mirja Puolakkainen ◽  
Aino Laurila ◽  
Kari Varkila ◽  
...  
Keyword(s):  
Primary Infection ◽  
Bacterial Infections ◽  
Chlamydia Pneumoniae ◽  
Mononuclear Cells ◽  
Relative Increase ◽  
Culturable Bacteria ◽  
Ifn Γ ◽  
Tissue Reactions

ABSTRACT Cell-mediated immune (CMI) responses play a major role in protection as well as pathogenesis of many intracellular bacterial infections. In this study, we evaluated the infection kinetics and assessed histologically the lymphoid reactions and local, in vitro-restimulated CMI responses in lungs of BALB/c mice, during both primary infection and reinfection with Chlamydia pneumoniae. The primary challenge resulted in a self-restricted infection with elimination of culturable bacteria by day 27 after challenge. A mild lymphoid reaction characterized the pathology in the lungs. In vitro CMI responses consisted of a weak proliferative response and no secretion of gamma interferon (IFN-γ). The number of lung-derived mononuclear cells increased substantially during the primary infection; the largest relative increase was observed in B cells (B220+). After reinfection, the number of lung-derived mononuclear cells increased further, and the response consisted mainly of T cells. The reinfection was characterized in vivo by significant protection from infection (fewer cultivable bacteria in the lungs for a shorter period of time) but increased local lymphoid reaction at the infection site. In vitro, as opposed to the response in naive mice, acquired immunity was characterized by a strongly Th1-biased (IFN-γ) CMI response. These results suggest that repeated infections with C. pneumoniae may induce Th1-type responses with similar associated tissue reactions, as shown in C. trachomatis infection models.

In Vitro and In Vivo Anti-Inflammatory Activity of the Rhizomes of Globba pendula Roxb

2021 ◽  
Vol 16 (10) ◽  
pp. 1934578X2110559
Author(s):  
Le Minh Ha ◽  
Ngo Thi Phuong ◽  
Nguyen Thi Thu Hien ◽  
Pham Thi Tam ◽  
Do Thi Thao ◽  
...  
Keyword(s):  
Ethyl Acetate ◽  
Ethyl Acetate Extract ◽  
Inhibitory Effect ◽  
Potential Effect ◽  
Inflammatory Activity ◽  
No Production ◽  
Anti Inflammatory ◽  
Inflammatory Effect

In this study, we aimed at evaluating in vitro and in vivo anti-inflammatory activity of various extracts of the rhizomes of Globba pendula Roxb. Three extracts ( n-hexane, ethyl acetate, and water) were screened for their inhibitory effect on NO production by lipopolysaccharide-stimulated RAW 264.7 macrophages. The ethyl acetate extract of G. pendula rhizomes (EGP) showed a potential effect with an IC50 value of 32.45 µg/mL. For in vivo study, the ethyl acetate extract was further investigated for its anti-inflammatory effect using collagen antibody-induced arthritic mice (CAIA). The level of arthritis in experimental mice significantly reduced ( P < .05) after treatment with EGP at a dose of 500 mg/kg body weight (b.w.). This study also revealed that EGP is orally non-toxic. Ethyl p-methoxy cinamate was identified as the main constituent of EGP, which may result in its anti-inflammatory effect.

scholarly journals Anthocyanins in Whole Grain Cereals and Their Potential Effect on Health

Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2922
Author(s):  
Alyssa Francavilla ◽  
Iris J. Joye
Keyword(s):  
Food Industry ◽  
Potential Effect ◽  
Research Field ◽  
Water Soluble ◽  
Antioxidant Potential ◽  
In Vivo Studies ◽  
Whole Grain ◽  
Grain Products

Coloured (black, purple, blue, red, etc.) cereal grains, rich in anthocyanins, have recently gained a lot of attention in the food industry. Anthocyanins are water-soluble flavonoids, and are responsible for red, violet, and blue colours in fruits, vegetables, and grains. Anthocyanins have demonstrated antioxidant potential in both in vitro and in vivo studies, and the consumption of foods high in anthocyanins has been linked to lower risks of chronic diseases. As such, whole grain functional foods made with coloured grains are promising new products. This paper will review the characteristics of cereal anthocyanins, and assess their prevalence in various commercially relevant crops including wheat, barley, maize, and rice. A brief overview of the antioxidant potential, and current research on the health effects of cereal-based anthocyanins will be provided. Finally, processing of coloured cereals in whole grain products will be briefly discussed. A full understanding of the fate of anthocyanins in whole grain products, and more research targeted towards health outcomes of anthocyanin supplementation to/inclusion in cereal food products are the next logical steps in this research field.

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