Salmonella-Induced Cell Death Is Not Required for Enteritis in Calves

ABSTRACT Salmonella enterica serovar Typhimurium causes cell death in bovine monocyte-derived and murine macrophages in vitro by asipB-dependent mechanism. During this process, SipB binds and activates caspase-1, which in turn activates the proinflammatory cytokine interleukin-1β through cleavage. We used bovine ileal ligated loops to address the role of serovar Typhimurium-induced cell death in induction of fluid accumulation and inflammation in this diarrhea model. Twelve perinatal calves had 6- to 9-cm loops prepared in the terminal ileum. They were divided into three groups: one group received an intralumen injection of Luria-Bertani broth as a control in 12 loops. The other two groups (four calves each) were inoculated with 0.75 × 109 CFU of either wild-type serovar Typhimurium (strain IR715) or a sopB mutant per loop in 12 loops. Hematoxylin and eosin-stained sections were scored for inflammation, and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL)-positive cells were detected in situ. Fluid accumulation began at 3 h postinfection (PI). Inflammation was detected in all infected loops at 1 h PI. The area of TUNEL-labeled cells in the wild-type infected loops was significantly higher than that of the controls at 12 h PI, when a severe inflammatory response and tissue damage had already developed. ThesopB mutant induced the same amount of TUNEL-positive cells as the wild type, but it was attenuated for induction of fluid secretion and inflammation. Our results indicate that serovar Typhimurium-induced cell death is not required to trigger an early inflammatory response and fluid accumulation in the ileum.

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The Homolog of the Gene bstA of the BTP1 Phage from Salmonella enterica Serovar Typhimurium ST313 Is an Antivirulence Gene in Salmonella enterica Serovar Dublin

Infection and Immunity ◽

10.1128/iai.00784-17 ◽

2017 ◽

Vol 86 (1) ◽

Cited By ~ 5

Author(s):

Ana Herrero-Fresno ◽

Irene Cartas Espinel ◽

Malene Roed Spiegelhauer ◽

Priscila Regina Guerra ◽

Karsten Wiber Andersen ◽

...

Keyword(s):

Salmonella Enterica ◽

Type Strain ◽

Wild Type Strain ◽

Luria Bertani ◽

Wild Type ◽

Content Type ◽

Serovar Typhimurium ◽

Cattle Blood

ABSTRACTIn a previous study, a novel virulence gene,bstA, identified in aSalmonella entericaserovar Typhimurium sequence type 313 (ST313) strain was found to be conserved in all publishedSalmonella entericaserovar Dublin genomes. In order to analyze the role of this gene in the host-pathogen interaction inS. Dublin, a mutant where this gene was deleted (S. Dublin ΔbstA) and a mutant which was further genetically complemented withbstA(S. Dublin 3246-C) were constructed and tested in models ofin vitroandin vivoinfection as well as during growth competition assays in M9 medium, Luria-Bertani broth, and cattle blood. In contrast to the results obtained for a strain ofS. Typhimurium ST313, the lack ofbstAwas found to be associated with increased virulence inS. Dublin. Thus,S. Dublin ΔbstAshowed higher levels of uptake than the wild-type strain during infection of mouse and cattle macrophages and higher net replication within human THP-1 cells. Furthermore, during mouse infections,S. Dublin ΔbstAwas more virulent than the wild type following a single intraperitoneal infection and showed an increased competitive index during competitive infection assays. Deletion ofbstAdid not affect either the amount of cytokines released by THP-1 macrophages or the cytotoxicity toward these cells. The histology of the livers and spleens of mice infected with the wild-type strain and theS. Dublin ΔbstAmutant revealed similar levels of inflammation between the two groups. The gene was not important for adherence to or invasion of human epithelial cells and did not influence bacterial growth in rich medium, minimal medium, or cattle blood. In conclusion, a lack ofbstAaffects the pathogenicity ofS. Dublin by decreasing its virulence. Therefore, it might be regarded as an antivirulence gene in this serovar.

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Increased cell death in osteopontin-deficient cardiac fibroblasts occurs by a caspase-3-independent pathway

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00098.2004 ◽

2004 ◽

Vol 287 (4) ◽

pp. H1730-H1739 ◽

Cited By ~ 37

Author(s):

Ron Zohar ◽

Baoqian Zhu ◽

Peter Liu ◽

Jaro Sodek ◽

C. A. McCulloch

Keyword(s):

Cell Death ◽

Caspase 3 ◽

Cardiac Fibroblasts ◽

Chromatin Condensation ◽

Terminal Deoxynucleotidyl Transferase ◽

Tunel Staining ◽

Wild Type ◽

Nuclear Fragmentation ◽

A Cell

Reperfusion-induced oxidative injury to the myocardium promotes activation and proliferation of cardiac fibroblasts and repair by scar formation. Osteopontin (OPN) is a proinflammatory cytokine that is upregulated after reperfusion. To determine whether OPN enhances fibroblast survival after exposure to oxidants, cardiac fibroblasts from wild-type (WT) or OPN-null (OPN−/−) mice were treated in vitro with H2O2to model reperfusion injury. Within 1 h, membrane permeability to propidium iodide (PI) was increased from 5 to 60% in OPN−/−cells but was increased to only 20% in WT cells. In contrast, after 1–8 h of treatment with H2O2, the percent of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-stained cells was more than twofold higher in WT than OPN−/−cells. Electron microscopy of WT cells treated with H2O2showed chromatin condensation, nuclear fragmentation, and cytoplasmic and nuclear shrinkage, which are consistent with apoptosis. In contrast, H2O2-treated OPN−/−cardiac fibroblasts exhibited cell and nuclear swelling and membrane disruption that are indicative of cell necrosis. Treatment of OPN−/−and WT cells with a cell-permeable caspase-3 inhibitor reduced the percentage of TUNEL staining by more than fourfold in WT cells but decreased staining in OPN−/−cells by ∼30%. Although the percentage of PI-permeable WT cells was reduced threefold, the percent of PI-permeable OPN−/−cells was not altered. Restoration of OPN expression in OPN−/−fibroblasts reduced the percentage of PI-permeable cells but not TUNEL staining after H2O2treatment. Thus H2O2-induced cell death in OPN-deficient cardiac fibroblasts is mediated by a caspase-3-independent, necrotic pathway. We suggest that the increased expression of OPN in the myocardium after reperfusion may promote fibrosis by protecting cardiac fibroblasts from cell death.

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Transmembrane prolyl 4-hydroxylase is a fourth prolyl 4-hydroxylase regulating EPO production and erythropoiesis

Blood ◽

10.1182/blood-2012-07-441824 ◽

2012 ◽

Vol 120 (16) ◽

pp. 3336-3344 ◽

Cited By ~ 36

Author(s):

Anu Laitala ◽

Ellinoora Aro ◽

Gail Walkinshaw ◽

Joni M. Mäki ◽

Maarit Rossi ◽

...

Keyword(s):

Cultured Cells ◽

Mrna Level ◽

Hypoxia Inducible Factor ◽

Mrna Levels ◽

Wild Type ◽

Α Subunit ◽

Hepcidin Expression ◽

In The Wild ◽

Hepcidin Mrna

AbstractAn endoplasmic reticulum transmembrane prolyl 4-hydroxylase (P4H-TM) is able to hydroxylate the α subunit of the hypoxia-inducible factor (HIF) in vitro and in cultured cells, but nothing is known about its roles in mammalian erythropoiesis. We studied such roles here by administering a HIF-P4H inhibitor, FG-4497, to P4h-tm−/− mice. This caused larger increases in serum Epo concentration and kidney but not liver Hif-1α and Hif-2α protein and Epo mRNA levels than in wild-type mice, while the liver Hepcidin mRNA level was lower in the P4h-tm−/− mice than in the wild-type. Similar, but not identical, differences were also seen between FG-4497–treated Hif-p4h-2 hypomorphic (Hif-p4h-2gt/gt) and Hif-p4h-3−/− mice versus wild-type mice. FG-4497 administration increased hemoglobin and hematocrit values similarly in the P4h-tm−/− and wild-type mice, but caused higher increases in both values in the Hif-p4h-2gt/gt mice and in hematocrit value in the Hif-p4h-3−/− mice than in the wild-type. Hif-p4h-2gt/gt/P4h-tm−/− double gene-modified mice nevertheless had increased hemoglobin and hematocrit values without any FG-4497 administration, although no such abnormalities were seen in the Hif-p4h-2gt/gt or P4h-tm−/− mice. Our data thus indicate that P4H-TM plays a role in the regulation of EPO production, hepcidin expression, and erythropoiesis.

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EVALUASI HEMATOTOKSIK SECARA IN VITRO NANOPARTIKEL ZnS HASIL REDUKSI BIOMATRIKS Eschericia coli

Majalah Farmasi dan Farmakologi ◽

10.20956/mff.v23i3.9398 ◽

2020 ◽

Vol 23 (3) ◽

pp. 82-84

Author(s):

Lisa Kurniati ◽

Andi Arjuna ◽

Sukamto S Mamada

Keyword(s):

Escherichia Coli ◽

Luria Bertani ◽

Luria Bertani Broth

Nanopartikel ZnS merupakan material semi konduktor yang memiliki sifat unik dan manfaat yang besar dibidang kesehatan, terutama sebagai antibakteri dan biomarker kanker. Walaupun demikian, informasi mengenai toksisitas dari nanopartikel ZnS masih sangat terbatas. Oleh karena itu, pada penelitian ini telah dilakukan evaluasi hematotoksisitas secara in vitro nanopartikel ZnS hasil reduksi biomatriks Escherichia coli. Penyiapan nanopartikel ZnS diawali dengan pencampuran dispersi ZnSO4 konsentrasi 200 bpj ke dalam medium Luria Bertani Broth (LBB) yang ditumbuhi E.Coli sebagai bioreduktor. Produk yang dihasilkan dikarakterisasi dengan uji photolimunisence (PL) dan spektrofotometri pada rentang panjang gelombang 250-700 nm. Hasilnya, nanopartikel ZnS berpendar biru dan diidentifikasi pada λmax 288 nm dengan absorbansi 0,905. Partikel yang dihasilkan kemudian didispersikan dengan variasi volume 30 µl, 40 µl, 50 µl pada larutan tyrod. Data persentase hemolisis secara berturut-turut adalah 32%, 39%, 22%, 0% (kontrol negatif) dan 100% (kontrol positif). Sehingga dapat disimpulkan bahwa nanopartikel ZnS hasil reduksi E.coli memberikan efek toksik terhadap sel darah merah

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Abstract 165: The 18 kDa FGF-2 Prevents the Doxorubicin-induced Cardiac Damage and Amp-activated Kinase Activation, in vitro and in vivo

Circulation Research ◽

10.1161/res.117.suppl_1.165 ◽

2015 ◽

Vol 117 (suppl_1) ◽

Author(s):

Navid Koleini ◽

Jon Jon Santiago ◽

Barbara E Nickel ◽

Robert Fandrich ◽

Davinder S Jassal ◽

...

Keyword(s):

Molecular Weight ◽

Cell Death ◽

Left Ventricular ◽

Left Ventricular Ejection ◽

Wild Type ◽

Rat Cardiomyocytes ◽

Ventricular Ejection Fraction ◽

Compound C

Introduction: Protection of the heart from chemotherapeutic (Doxorubicin, DOX) drug-induced toxicity is a desirable goal, to limit side effects of cancer treatments. DOX toxicity has been linked to the activation (phosphorylation) of the AMP-activated kinase, AMPK. The 18 kDa low molecular weight isoform of fibroblast growth factor 2 (Lo-FGF-2) is a known cardioprotective and cytoprotective agent. In this study we have tested the ability of Lo-FGF-2 to protect from DOX-induced damage in rat cardiomyocytes in vitro, and in transgenic mouse models in vivo, in relation to AMPK activation. Methods: Rat neonatal cardiomyocytes in culture were exposed to DOX (0.5 μM) in the presence or absence of pre-treatment Lo-FGF-2 (10 ng/ml). Compound C was used to block phosphorylation (activity) of AMPK. Levels of cell viability/death (using Calcein-AM/Propidium iodide assay), phospho -and total AMPK, and apoptotic markers such as active caspase 3 were analyzed. In addition, transgenic mice expressing only Lo-FGF2, and wild type mice, expressing both high molecular weight (Hi-FGF2) as well as Lo-FGF2 were subjected to DOX injection (20 mg/kg, intraperitoneal); echocardiography was used to examine cardiac function at baseline and at 10 days post-DOX. Results: DOX-induced cell death of cardiomyocytes in culture was maximal at 24 hours post-DOX coinciding with significantly increased in activated (phosphorylated) AMPK. Compound C attenuated DOX-induced cardiomyocyte loss. Pre-incubation with Lo-FGF-2 decreased DOX induced cell death, and also attenuated the phosphorylation of AMPK post-DOX. Relative levels of phospho-AMPK were lower in the hearts of Lo-FGF2-expressing male mice compared to wild type. DOX-induced loss of contractile function (left ventricular ejection fraction and endocardial velocity) was negligible in Lo-FGF2-expressing mice but significant in wild type mice. Conclusion: Lo-FGF-2 protects the heart from DOX-induced damage in vitro and in vivo, by a mechanism likely involving an attenuation of AMPK activity.

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The pattern of cell death in fushi tarazu, a segmentation gene of Drosophila

Development ◽

10.1242/dev.104.3.447 ◽

1988 ◽

Vol 104 (3) ◽

pp. 447-451 ◽

Cited By ~ 4

Author(s):

L. Magrassi ◽

P.A. Lawrence

Keyword(s):

Cell Death ◽

Wild Type ◽

Germ Band ◽

Fushi Tarazu ◽

Larval Cuticle ◽

Dividing Cells ◽

In The Wild ◽

Indirect Consequence ◽

Dying Cells ◽

Pair Rule

The pair-rule mutant, fushi tarazu, causes deletion of alternate metameres. Here we show that there is cell death in the mutant which begins at the completion of germ band extension. We map the dying cells in the epidermis; they occur scattered all over those regions that, in the wild type, would form the even-numbered parasegments and are also found in posterior parts of the odd-numbered parasegments. In the affected zones, dying and dividing cells are intermingled; we suggest that cells from these zones may still give descendents that contribute to the larval cuticle. Cell death is not limited to those cells that would normally express ftz+, suggesting that it is some indirect consequence of the abnormal situation in the mutant embryo.

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Antimicrobial and Antibiofilm Properties of Graphene Oxide on Enterococcus faecalis

Antibiotics ◽

10.3390/antibiotics9100692 ◽

2020 ◽

Vol 9 (10) ◽

pp. 692

Author(s):

Cecilia Martini ◽

Francesca Longo ◽

Raffaella Castagnola ◽

Luca Marigo ◽

Nicola Maria Grande ◽

...

Keyword(s):

Graphene Oxide ◽

Enterococcus Faecalis ◽

Antibacterial Properties ◽

Luria Bertani ◽

Bacterial Suspension ◽

Adhesion Properties ◽

High Antibacterial Activity ◽

Luria Bertani Broth ◽

Bacterial Film

The aim of this study was to evaluate the antibacterial properties of graphene oxide (GO) against Enterococcus faecalis in vitro conditions and when used to coat dentin surface to prevent E. faecalis adhesion. The ATCC strain of E. faecalis 29212 has been used to perform a viability test. The pellet was suspended in ultrapure water, NaCl, PBS buffer, CaCl2 and MgCl2, Luria−Bertani broth solutions. The viability was evaluated by the colony forming unit counting method. Atomic force microscopy images and the measure of surface zeta potential variation were analyzed. Dentin discs were covered with a film of GO (n = 15) or were not treated (n = 15). Bacterial suspension was added to each sample of dentine discs and microbial counts were calculated. Statistically significant differences between two groups were assessed by a two-tailed unpaired t-test. Bacteria cell morphology was investigated with scanning electron microscopy. The highest growth inhibition was obtained in ddH2O and CaCl2 solution while, in PBS and NaCl, GO had poor antibacterial efficacy with a growth enhancing effect in the latter. GO on dentin discs demonstrated high antibacterial activity. GO film has demonstrated acceptable adhesion properties to root dentin and a role in the inhibition of bacterial film proliferation and biofilm formation.

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Novel Salmonella enterica Serovar Typhimurium Protein That Is Indispensable for Virulence and Intracellular Replication

Infection and Immunity ◽

10.1128/iai.69.12.7413-7418.2001 ◽

2001 ◽

Vol 69 (12) ◽

pp. 7413-7418 ◽

Cited By ~ 11

Author(s):

Tahar van der Straaten ◽

Angela van Diepen ◽

Kitty Kwappenberg ◽

Sjaak van Voorden ◽

Kees Franken ◽

...

Keyword(s):

Amino Acid ◽

Protein Function ◽

Salmonella Enterica ◽

Host Cells ◽

Wild Type ◽

Intracellular Replication ◽

Oxygen Intermediates ◽

Serovar Typhimurium

ABSTRACT Upon contact with host cells, the intracellular pathogenSalmonella enterica serovar Typhimurium promotes its uptake, targeting, and survival in intracellular niches. In this process, the bacterium evades the microbicidal effector mechanisms of the macrophage, including oxygen intermediates. This study reports the phenotypic and genotypic characterization of an S. enterica serovar Typhimurium mutant that is hypersusceptible to superoxide. The susceptible phenotype is due to a MudJ insertion-inactivation of a previously undescribedSalmonella gene designated sspJ that is located between 54.4 and 64 min of the Salmonellachromosome and encodes a 392-amino-acid protein. In vivo, upon intraperitoneal injection of 104 to 107bacteria in C3H/HeN and 101 to 104 bacteria in BALB/c mice, the mutant strain was less virulent than the wild type. Consistent with this finding, during the first hour after ingestion by macrophage-like J774 and RAW264.7 cells in vitro, the intracellular killing of the strain carrying sspJ::MudJ is enhanced fivefold over that of wild-type microorganisms. Wild-type salmonellae displayed significant intracellular replication during the first 24 h after uptake, but sspJ::MudJ mutants failed to do so. This phenotype could be restored to that of the wild type by sspJ complementation. The SspJ protein is found in the cytoplasmic membrane and periplasmic space. Amino acid sequence homology analysis did reveal a leader sequence and putative pyrroloquinoline quinone-binding domains, but no putative protein function. We excluded the possibility that SspJ is a scavenger of superoxide or has superoxide dismutase activity.

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Colonization and Inflammation Deficiencies in Mongolian Gerbils Infected by Helicobacter pylori Chemotaxis Mutants

Infection and Immunity ◽

10.1128/iai.73.3.1820-1827.2005 ◽

2005 ◽

Vol 73 (3) ◽

pp. 1820-1827 ◽

Cited By ~ 78

Author(s):

David J. McGee ◽

Melanie L. Langford ◽

Emily L. Watson ◽

J. Elliot Carter ◽

Yu-Ting Chen ◽

...

Keyword(s):

Helicobacter Pylori ◽

Immune Cell ◽

Response Regulator ◽

Critical Role ◽

Mongolian Gerbils ◽

Wild Type ◽

In The Wild ◽

H Pylori

ABSTRACT Helicobacter pylori causes disease in the human stomach and in mouse and gerbil stomach models. Previous results have shown that motility is critical for H. pylori to colonize mice, gerbils, and other animal models. The role of chemotaxis, however, in colonization and disease is less well understood. Two genes in the H. pylori chemotaxis pathway, cheY and tlpB, which encode the chemotaxis response regulator and a methyl-accepting chemoreceptor, respectively, were disrupted. The cheY mutation was complemented with a wild-type copy of cheY inserted into the chromosomal rdxA gene. The cheY mutant lost chemotaxis but retained motility, while all other strains were motile and chemotactic in vitro. These strains were inoculated into gerbils either alone or in combination with the wild-type strain, and colonization and inflammation were assessed. While the cheY mutant completely failed to colonize gerbil stomachs, the tlpB mutant colonized at levels similar to those of the wild type. With the tlpB mutant, there was a substantial decrease in inflammation in the gerbil stomach compared to that with the wild type. Furthermore, there were differences in the numbers of each immune cell in the tlpB-mutant-infected stomach: the ratio of lymphocytes to neutrophils was about 8 to 1 in the wild type but only about 1 to 1 in the mutant. These results suggest that the TlpB chemoreceptor plays an important role in the inflammatory response while the CheY chemotaxis regulator plays a critical role in initial colonization. Chemotaxis mutants may provide new insights into the steps involved in H. pylori pathogenesis.

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Flagellar Phase Variation of Salmonella enterica Serovar Typhimurium Contributes to Virulence in the Murine Typhoid Infection Model but Does Not InfluenceSalmonella-Induced Enteropathogenesis

Infection and Immunity ◽

10.1128/iai.69.5.3021-3030.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 3021-3030 ◽

Cited By ~ 79

Author(s):

Jack S. Ikeda ◽

Clare K. Schmitt ◽

Stephen C. Darnell ◽

Patricia R. Watson ◽

Jennifer Bispham ◽

...

Keyword(s):

Epithelial Cells ◽

Salmonella Enterica ◽

Phase Variation ◽

Selective Advantage ◽

Peritoneal Macrophages ◽

Infection Model ◽

Wild Type ◽

Two Phase ◽

Serovar Typhimurium

ABSTRACT Although Salmonella enterica serovar Typhimurium can undergo phase variation to alternately express two different types of flagellin subunit proteins, FljB or FliC, no biological function for this phenomenon has been described. In this investigation, we constructed phase-locked derivatives of S. enterica serovar Typhimurium that expressed only FljB (termed locked-ON) or FliC (termed locked-OFF). The role of phase variation in models of enteric and systemic pathogenesis was then evaluated. There were no differences between the wild-type parent strain and the two phase-locked derivatives in adherence and invasion of mouse epithelial cells in vitro, survival in mouse peritoneal macrophages, or in a bovine model of gastroenteritis. By contrast, the locked-OFF mutant was virulent in mice following oral or intravenous (i.v.) inoculation but the locked-ON mutant was attenuated. When these phase-locked mutants were compared in studies of i.v. kinetics in mice, similar numbers of the two strains were isolated from the blood and spleens of infected animals at 6 and 24 h. However, the locked-OFF mutant was recovered from the blood and spleens in significantly greater numbers than the locked-ON strain by day 2 of infection. By 5 days postinfection, a majority of the mice infected with the locked-OFF mutant had died compared with none of the mice infected with the locked-ON mutant. These results suggest that phase variation is not involved in the intestinal stage of infection but that once S. enterica serovar Typhimurium reaches the spleens of susceptible mice those organisms in the FliC phase can grow and/or survive better than those in the FljB phase. Additional experiments with wild-type S. enterica serovar Typhimurium, fully capable of switching flagellin type, supported this hypothesis. We conclude that organisms that have switched to the FliC+phase have a selective advantage in the mouse model of typhoid fever but have no such advantage in invasion of epithelial cells or the induction of enteropathogenesis.

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