Quantitative Proteomics Reveal Distinct Protein Regulations Caused by Aggregatibacter actinomycetemcomitans within Subgingival Biofilms

PubMed Central

Bao, Kai; Bostanci, Nagihan; Selevsek, Nathalie; Thurnheer, Thomas; Belibasakis, Georgios N.

2015-01-01

Periodontitis is an infectious disease that causes the inflammatory destruction of the tooth-supporting (periodontal) tissues, caused by polymicrobial biofilm communities growing on the tooth surface. Aggressive periodontitis is strongly associated with the presence of Aggregatibacter actinomycetemcomitans in the subgingival biofilms. Nevertheless, whether and how A. actinomycetemcomitans orchestrates molecular changes within the biofilm is unclear. The aim of this work was to decipher the interactions between A. actinomycetemcomitans and other bacterial species in a multi-species biofilm using proteomic analysis. An in vitro 10-species “subgingival” biofilm model, or its derivative that included additionally A. actinomycetemcomitans, were anaerobically cultivated on hydroxyapatite discs for 64 h. When present, A. actinomycetemcomitans formed dense intra-species clumps within the biofilm mass, and did not affect the numbers of the other species in the biofilm. Liquid chromatography-tandem mass spectrometry was used to identify the proteomic content of the biofilm lysate. A total of 3225 and 3352 proteins were identified in the biofilm, in presence or absence of A. actinomycetemcomitans, respectively. Label-free quantitative proteomics revealed that 483 out of the 728 quantified bacterial proteins (excluding those of A. actinomycetemcomitans) were accordingly regulated. Interestingly, all quantified proteins from Prevotella intermedia were up-regulated, and most quantified proteins from Campylobacter rectus, Streptococcus anginosus, and Porphyromonas gingivalis were down-regulated in presence of A. actinomycetemcomitans. Enrichment of Gene Ontology pathway analysis showed that the regulated groups of proteins were responsible primarily for changes in the metabolic rate, the ferric iron-binding, and the 5S RNA binding capacities, on the universal biofilm level. While the presence of A. actinomycetemcomitans did not affect the numeric composition or absolute

Both Leukotoxin and Poly-N-Acetylglucosamine Surface Polysaccharide Protect Aggregatibacter actinomycetemcomitans Cells from Macrophage Killing

PubMed Central

Venketaraman, Vishwanath; Lin, Albert K.; Le, Amy; Kachlany, Scott C.; Connell, Nancy D.; Kaplan, Jeffrey B.

2008-01-01

Two virulence factors produced by the periodontopathogen Aggregatibacter actinomycetemcomitans are leukotoxin, a secreted lipoprotein that kills human polymorphonuclear leukocytes and macrophages, and poly-N-acetylglucosamine (PGA), a surface polysaccharide that mediates intercellular adhesion, biofilm formation and detergent resistance. In this study we examined the roles of leukotoxin and PGA in protecting A. actinomycetemcomitans cells from killing by the human macrophage cell line THP-1. Monolayers of THP-1 cells were infected with single-cell suspensions of a wild-type A. actinomycetemcomitans strain, or of isogenic leukotoxin or PGA mutant strains. After 48 h, viable bacteria were enumerated by dilution plating, macrophage morphology was evaluated microscopically, and macrophage viability was measured by a Trypan blue dye exclusion assay. The number of A. actinomycetemcomitans CFUs increased approximately 2-fold in wells infected with the wild-type strain, but decreased by approximately 70–90% in wells infected with the leukotoxin and PGA mutant strains. Infection with the wild-type or leukotoxin mutant strain caused a significant decrease in THP-1 cell viability, whereas infection with the PGA mutant strain did not result in any detectable changes in THP-1 viability. Pre-treatment of wild-type A. actinomycetemcomitans cells with the PGA-hydrolyzing enzyme dispersin B rendered them sensitive to killing by THP-1 cells. We concluded that both leukotoxin and PGA are necessary for evasion of macrophage killing by A. actinomycetemcomitans. PMID:18573331

Aggregatibacter actinomycetemcomitans-Induced AIM2 Inflammasome Activation Is Suppressed by Xylitol in Differentiated THP-1 Macrophages.

PubMed

Kim, Seyeon; Park, Mi Hee; Song, Yu Ri; Na, Hee Sam; Chung, Jin

2016-06-01

Aggressive periodontitis is characterized by rapid destruction of periodontal tissue caused by Aggregatibacter actinomycetemcomitans. Interleukin (IL)-1β is a proinflammatory cytokine, and its production is tightly regulated by inflammasome activation. Xylitol, an anticaries agent, is anti-inflammatory, but its effect on inflammasome activation has not been researched. This study investigates the effect of xylitol on inflammasome activation induced by A. actinomycetemcomitans. The differentiated THP-1 macrophages were stimulated by A. actinomycetemcomitans with or without xylitol and the expressions of IL-1β and inflammasome components were detected by real time PCR, ELISA, confocal microscopy and Immunoblot analysis. The effects of xylitol on the adhesion and invasion of A. actinomycetemcomitans to cells were measured by viable cell count. A. actinomycetemcomitans increased pro IL-1β synthesis and IL-1β secretion in a multiplicity of infection- and time-dependent manner. A. actinomycetemcomitans also stimulated caspase-1 activation. Among inflammasome components, apoptosis-associated speck-like protein containing a CARD (ASC) and absent in melanoma 2 (AIM2) proteins were upregulated by A. actinomycetemcomitans infection. When cells were pretreated with xylitol, proIL-1β and IL-1β production by A. actinomycetemcomitans infection was significantly decreased. Xylitol also inhibited ASC and AIM2 proteins and formation of ASC puncta. Furthermore, xylitol suppressed internalization of A. actinomycetemcomitans into differentiated THP-1 macrophages without affecting viability of A. actinomycetemcomitans within cells. A. actinomycetemcomitans induced IL-1β production and AIM2 inflammasome activation. Xylitol inhibited these effects, possibly by suppressing internalization of A. actinomycetemcomitans into cells. Thus, this study proposes a mechanism for IL-1β production via inflammasome activation and discusses a possible use for xylitol in periodontal inflammation

[A case of mediastinum actinomycosis by Aggregatibacter actinomycetemcomitans].

PubMed

Razafimanjato, N N M; Portela, A M; Radu, D M; Guiraudet, P; Destable, M D; Seguin, A; Martinod, E

2016-12-01

The actinomycosis is a suppurative infection due to an anaerobic and microaerophillic bacteria called actinomyces. Only few case reports are described for the mediastinal locations of this rare entity. We report a new case of inflammatory pseudotumor in the mediastinum due to Aggregatibacte actinomycetemcomitans revealed by hemoptysis. The mediastinoscopy procedure with biopsy was needed to confirm the definitive bacteriological diagnosis by a positive culture. During the postoperative course, a cutaneous fistula was found which had a favourable evolution after appropriate antibiotherapy. Through this case report, the authors insist upon the importance of considering the diagnosis of mediastinal actinomycosis when facing non-specfic mediastinal mass symptoms and also about the interest of systematic bacterioscopic examination and histopathologic examination on nodes' biopsies to avoid to be lost on pathology of mediastinal tumor or tuberculosis. In practise, we caution the non-expert during biopsies because of this lesion's invasive characteristic especially in the confined space of the mediastinum. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Neutrophils in chronic and aggressive periodontitis in interaction with Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans

PubMed Central

Guentsch, Arndt; Puklo, Magdalena; Preshaw, Philip M.; Glockmann, Eike; Pfister, Wolfgang; Potempa, Jan; Eick, Sigrun

2014-01-01

AIM The aim of this in vitro study was to study phagocytosis and killing of Porphyromonas gingivalis ATCC 33277 and Aggregatibacter actinomycetemcomitans Y4 by peripheral blood PMNs taken from aggressive and chronic periodontitis patients. Also, the release of reactive oxygen species (ROS) and human neutrophil elastase (HNE) upon the interaction of PMNs with bacteria was measured. METHODS Peripheral blood PMNs obtained from 12 chronic periodontitis patients, 6 aggressive periodontitis patients and 12 healthy controls were exposed to Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans following opsonisation of the bacteria using the patient’s own serum. Phagocytosis and killing of the bacteria as well as the extracellular HNE activity were quantified for up to 2 hours. The total amount and the extracellular release of ROS were measured by luminol and isoluminol dependent chemiluminescence. RESULTS PMNs from chronic (62.16 ± 19.39 %) and aggressive periodontitis (43.26 ± 26.63 %) patients phagocytosed more P. gingivalis than the healthy controls (24.43 ± 19.87 %) at 30 mins after exposure to the bacteria (p < 0.05). PMNs from subjects with chronic and aggressive periodontitis released significantly more ROS and demonstrated greater HNE activity in the absence of any stimulus than PMNs from healthy controls (p < 0.05). The total release of ROS increased in chronic periodontitis PMNs and in the control group PMNs after interaction with P. gingivalis. The interaction with A. actinomycetemcomitans resulted in greater total ROS release in chronic periodontitis PMNs and in the control group PMNs than P. gingivalis. CONCLUSION PMNs in aggressive and chronic periodontitis are hyperactive even without any particular stimulus. The extracellular release of ROS and neutrophil elastase by PMNs may not only affect bacterial virulence and/or viability, but also contribute to damage of the surrounding periodontal tissues. PMID:19210340

Mitogen-Activated Protein Kinase 2 Signaling Shapes Macrophage Plasticity in Aggregatibacter actinomycetemcomitans-Induced Bone Loss

PubMed Central

Herbert, Bethany A.; Steinkamp, Heidi M.; Gaestel, Matthias

2016-01-01

ABSTRACT Aggregatibacter actinomycetemcomitans is associated with aggressive periodontal disease, which is characterized by inflammation-driven alveolar bone loss. A. actinomycetemcomitans activates the p38 mitogen-activated protein kinase (MAPK) and MAPK-activated protein kinase 2 (MK2) stress pathways in macrophages that are involved in host responses. During the inflammatory process in periodontal disease, chemokines are upregulated to promote recruitment of inflammatory cells. The objective of this study was to determine the role of MK2 signaling in chemokine regulation during A. actinomycetemcomitans pathogenesis. Utilizing a murine calvarial model, Mk2+/+ and Mk2−/− mice were treated with live A. actinomycetemcomitans bacteria at the midsagittal suture. MK2 positively regulated the following macrophage RNA: Emr1 (F4/80), Itgam (CD11b), Csf1r (M-CSF Receptor), Itgal (CD11a), Tnf, and Nos2. Additionally, RNA analysis revealed that MK2 signaling regulated chemokines CCL3 and CCL4 in murine calvarial tissue. Utilizing the chimeric murine air pouch model, MK2 signaling differentially regulated CCL3 and CCL4 in the hematopoietic and nonhematopoietic compartments. Bone resorption pits in calvaria, observed by micro-computed tomography, and osteoclast formation were decreased in Mk2−/− mice compared to Mk2+/+ mice after A. actinomycetemcomitans treatment. In conclusion, these data suggest that MK2 in macrophages contributes to regulation of chemokine signaling during A. actinomycetemcomitans-induced inflammation and bone loss. PMID:27795356

Clarithromycin accumulation by phagocytes and its effect on killing of Aggregatibacter actinomycetemcomitans.

PubMed

Iskandar, Irma; Walters, John D

2011-03-01

Clarithromycin inhibits several periodontal pathogens and is concentrated inside gingival fibroblasts and epithelial cells by an active transporter. We hypothesized that polymorphonuclear leukocytes (PMNs) and less mature myeloid cells possess a similar transporter for clarithromycin. It is feasible that clarithromycin accumulation inside PMNs could enhance their ability to kill Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans). To test the first hypothesis, purified PMNs and cultured HL-60 cells were incubated with [(3)H]-clarithromycin. Clarithromycin transport was assayed by measuring changes in cell-associated radioactivity over time. The second hypothesis was examined with PMNs loaded by incubation with clarithromycin (5 μg/ml). Opsonized bacteria were incubated at 37°C with control and clarithromycin-loaded PMNs. Mature human PMNs, HL-60 cells differentiated into granulocytes, and undifferentiated HL-60 cells all took up clarithromycin in a saturable manner. The kinetics of uptake by all yielded linear Lineweaver-Burk plots. HL-60 granulocytes transported clarithromycin with a K(m) of ≈250 μg/ml and a V(max) of 473 ng/min/10(6) cells, which were not significantly different from the values obtained with PMNs. At steady state, clarithromycin levels inside HL-60 granulocytes and PMNs were 28- to 71-fold higher than extracellular levels. Clarithromycin-loaded PMNs killed significantly more A. actinomycetemcomitans and achieved shorter half-times for killing than control PMNs when assayed at a bacteria-to-PMN ratio of 100:1 (P <0.04). At a ratio of 30:1, these differences were not consistently significant. PMNs and less mature myeloid cells possess a transporter that takes up and concentrates clarithromycin. This system could help PMNs cope with an overwhelming infection by A. actinomycetemcomitans.

Dual action of highbush blueberry proanthocyanidins on Aggregatibacter actinomycetemcomitans and the host inflammatory response.

PubMed

Ben Lagha, Amel; LeBel, Geneviève; Grenier, Daniel

2018-01-10

The highbush blueberry (Vaccinium corymbosum) has a beneficial effect on several aspects of human health. The present study investigated the effects of highbush blueberry proanthocyanidins (PACs) on the virulence properties of Aggregatibacter actinomycetemcomitans and macrophage-associated inflammatory responses. PACs were isolated from frozen highbush blueberries using solid-phase chromatography. A microplate dilution assay was performed to determine the effect of highbush blueberry PACs on A. actinomycetemcomitans growth as well as biofilm formation stained with crystal violet. Tight junction integrity of oral keratinocytes was assessed by measuring the transepithelial electrical resistance (TER), while macrophage viability was determined with a colorimetric MTT assay. Pro-inflammatory cytokine and MMP secretion by A. actinomycetemcomitans-stimulated macrophages was quantified by ELISA. The U937-3xκB-LUC monocyte cell line transfected with a luciferase reporter gene was used to monitor NF-κB activation. Highbush blueberry PACs reduced the growth of A. actinomycetemcomitans and prevented biofilm formation at sub-inhibitory concentrations. The treatment of pre-formed biofilms with the PACs resulted in a loss of bacterial viability. The antibacterial activity of the PACs appeared to involve damage to the bacterial cell membrane. The PACs protected the oral keratinocytes barrier integrity from damage caused by A. actinomycetemcomitans. The PACs also protected macrophages from the deleterious effect of leukotoxin Ltx-A and dose-dependently inhibited the secretion of pro-inflammatory cytokines (IL-1β, IL-6, CXCL8, TNF-α), matrix metalloproteinases (MMP-3, MMP-9), and sTREM-1 by A. actinomycetemcomitans-treated macrophages. The PACs also inhibited the activation of the NF-κB signaling pathway. The antibacterial and anti-inflammatory properties of highbush blueberry PACs as well as their ability to protect the oral keratinocyte barrier and neutralize leukotoxin

Identification and functional characterization of type II toxin/antitoxin systems in Aggregatibacter actinomycetemcomitans.

PubMed

Schneider, B; Weigel, W; Sztukowska, M; Demuth, D R

2018-06-01

Type II toxin/antitoxin (TA) systems contribute to the formation of persister cells and biofilm formation for many organisms. Aggregatibacter actinomycetemcomitans thrives in the complex oral microbial community subjected to continual environmental flux. Little is known regarding the presence and function of type II TA systems in this organism or their contribution to adaptation and persistence in the biofilm. We identified 11 TA systems that are conserved across all seven serotypes of A. actinomycetemcomitans and represent the RelBE, MazEF and HipAB families of type II TA systems. The systems selectively responded to various environmental conditions that exist in the oral cavity. Two putative RelBE-like TA systems, D11S_1194-1195 and D11S_1718-1719 were induced in response to low pH and deletion of D11S_1718-1719 significantly reduced metabolic activity of stationary phase A. actinomycetemcomitans cells upon prolonged exposure to acidic conditions. The deletion mutant also exhibited reduced biofilm biomass when cultured under acidic conditions. The D11S_1194 and D11S_1718 toxin proteins inhibited in vitro translation of dihydrofolate reductase (DHFR) and degraded ribosome-associated, but not free, MS2 virus RNA. In contrast, the corresponding antitoxins (D11S_1195 and D11S_1719), or equimolar mixtures of toxin and antitoxin, had no effect on DHFR production or RNA degradation. Together, these results suggest that D11S_1194-1195 and D11S_1718-1719 are RelBE-like type II TA systems that are activated under acidic conditions and may function to cleave ribosome-associated mRNA to inhibit translation in A. actinomycetemcomitans. In vivo, these systems may facilitate A. actinomycetemcomitans adaptation and persistence in acidic local environments in the dental biofilm. © 2018 The Authors. Molecular Oral Microbiology Published by John Wiley & Sons Ltd.

Neutrophils in chronic and aggressive periodontitis in interaction with Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans.

PubMed

Guentsch, A; Puklo, M; Preshaw, P M; Glockmann, E; Pfister, W; Potempa, J; Eick, S

2009-06-01

This study analyzed the interaction of Porphyromonas gingivalis ATCC 33277 and Aggregatibacter actinomycetemcomitans Y4 with peripheral blood polymorphonuclear neutrophils taken from patients with aggressive periodontitis and chronic periodontitis. Peripheral blood polymorphonuclear neutrophils obtained from 12 patients with chronic periodontitis, six patients with aggressive periodontitis and 12 healthy controls were exposed to P. gingivalis and A. actinomycetemcomitans following opsonization of the bacteria using the patient's own serum. Serum immunoglobulin G (IgG) levels against both periodontopathogens were measured. Phagocytosis and killing of the bacteria, as well as the extracellular human neutrophil elastase activity, were quantified. The total amount and the extracellular release of reactive oxygen species were measured using luminol-dependent and isoluminol-dependent chemiluminescence. Polymorphonuclear neutrophils from patients with chronic (62.16 +/- 19.39%) and aggressive (43.26 +/- 26.63%) periodontitis phagocytosed more P. gingivalis than the healthy controls (24.43 +/- 19.87%) at the 30-min time point after exposure to the bacteria (p < 0.05). High serum IgG levels against P. gingivalis and A. actinomycetemcomitans were detected in subjects with periodontitis. Polymorphonuclear neutrophils from subjects with chronic and aggressive periodontitis released significantly more reactive oxygen species and demonstrated greater human neutrophil elastase activity in the absence of any stimulus than polymorphonuclear neutrophils from healthy controls (p < 0.05). Polymorphonuclear neutrophils in chronic periodontitis released significantly more reactive oxygen species when exposed to P. gingivalis and A. actinomycetemcomitans than polymorphonuclear neutrophils in aggressive periodontitis. High serum IgG levels against P. gingivalis and A. actinomycetemcomitans promote phagocytosis in periodontitis. The extracellular release of reactive oxygen species and

Aggregatibacter actinomycetemcomitans osteomyelitis in a 12 year old boy: case report emphasizing the importance of tissue culture, and review of literature.

PubMed

Sharma, Ketaki; Mudgil, Poonam; Whitehall, John S; Gosbell, Iain

2017-03-14

Aggregatibacter actinomycetemcomitans most commonly causes periodontitis but has been reported to infect heart valves, soft tissue, brain and lungs, and distal bones. Osteomyelitis distal to the jaw is rarely described. We report an unusual and rare case of chronic osteomyelitis caused by A. actinomycetemcomitans in the toe of a paediatric patient, and review the available literature. The infection was managed with intravenous antibiotics followed by oral antibiotics. This is an unusual presentation of A. actinomycetemcomitans causing chronic osteomyelitis presumed due to nidation in a minimally damaged bone, associated with bacteraemia of an oral commensal. It occurred in the toe, without obvious dental predisposition; associated with minimal clinical disturbance and with muted immune response.

Cytolethal distending toxin in isolates of Aggregatibacter actinomycetemcomitans from Ghanaian adolescents and association with serotype and disease progression.

PubMed

Höglund Åberg, Carola; Antonoglou, Georgios; Haubek, Dorte; Kwamin, Francis; Claesson, Rolf; Johansson, Anders

2013-01-01

The cytolethal distending toxin (Cdt) is a highly conserved exotoxin that are produced by a number of Gram negative bacteria, including Aggregatibacter actinomycetemcomitans, and affects mammalian cells by inhibiting cell division and causing apoptosis. A complete cdt-operon is present in the majority of A. actinomycetemcomitans, but the proportion of isolates that lack cdt-encoding genes (A, B and C) varies according to the population studied. The objectives of this study were to examine serotype, Cdt-genotype, and Cdt-activity in isolates of A. actinomycetemcomitans collected from an adolescent West African population and to examine the association between the carrier status of A. actinomycetemcomitans and the progression of attachment loss (AL). A total of 249 A. actinomycetemcomitans isolates from 200 Ghanaian adolescents were examined for serotype and cdt-genotype by PCR. The activity of the Cdt-toxin was examined by DNA-staining of exposed cultured cells and documented with flow cytometry. The periodontal status of the participants was examined at baseline and at a two-year follow-up. Presence of all three cdt-encoding genes was detected in 79% of the examined A. actinomycetemcomitans isolates. All these isolates showed a substantial Cdt-activity. The two different cdt-genotypes (with and without presence of all three cdt-encoding genes) showed a serotype-dependent distribution pattern. Presence of A. actinomycetemcomitans was significantly associated with progression of AL (OR = 5.126; 95% CI = [2.994-8.779], p<0.001). A. actinomycetemcomitans isolated from the Ghanaian adolescents showed a distribution of serotype and cdt-genotype in line with results based on other previously studied populations. Presence of A. actinomycetemcomitans was significantly associated with disease progression, in particular the b serotype, whereas the association with disease progression was not particularly related to cdt-genotype, and Cdt-activity.

Construction of new cloning, lacZ reporter and scarless-markerless suicide vectors for genetic studies in Aggregatibacter actinomycetemcomitans

PubMed Central

Juárez-Rodríguez, María Dolores; Torres-Escobar, Ascención; Demuth, Donald R.

2013-01-01

To elucidate the putative function of a gene, effective tools are required for genetic characterization that facilitate its inactivation, deletion or modification on the bacterial chromosome. In the present study, the nucleotide sequence of the Escherichia coli/Aggregatibacter actinomycetemcomitans shuttle vector pYGK was determined, allowing us to redesign and construct a new shuttle cloning vector, pJT4, and promoterless lacZ transcriptional/translational fusion plasmids, pJT3 and pJT5. Plasmids pJT4 and pJT5 contain the origin of replication necessary to maintain shuttle vector replication. In addition, a new suicide vector, pJT1, was constructed for the generation of scarless and markerless deletion mutations of genes in the oral pathogen A. actinomycetemcomitans. Plasmid pJT1 is a pUC-based suicide vector that is counter-selectable for sucrose sensitivity. This vector does not leave antibiotic markers or scars on the chromosome after gene deletion and thus provides the option to combine several mutations in the same genetic background. The effectiveness of pJT1 was demonstrated by the construction of A. actinomycetemcomitans isogenic qseB single deletion (ΔqseB) mutant and lsrRK double deletion mutants (ΔlsrRK). These new vectors may offer alternatives for genetic studies in A. actinomycetemcomitans and other members of the HACEK (Haemophilus spp., A. actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) group of Gram-negative bacteria. PMID:23353051

Detection of antimicrobial activity of banana peel (Musa paradisiaca L.) on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans: An in vitro study.

PubMed

Kapadia, Suraj Premal; Pudakalkatti, Pushpa S; Shivanaikar, Sachin

2015-01-01

Banana is used widely because of its nutritional values. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms but has not been studied extensively. Since, there are no studies that relate the antibacterial activity of banana peel against periodontal pathogens. Hence, the aim of this study is to determine the antimicrobial activity of banana peel extract on Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans). Standard strains of P. gingivalis and A. actinomycetemcomitans were used in this study which was obtained from the in-house bacterial bank of Department of Molecular Biology and Immunology at Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre. The banana peel extract was prepared, and the antibacterial activity was assessed using well agar diffusion method and minimum inhibitory concentration was assessed using serial broth dilution method. In the current study, both the tested microorganisms showed antibacterial activity. In well diffusion method, P. gingivalis and A. actinomycetemcomitans showed 15 mm and 12 mm inhibition zone against an alcoholic extract of banana peel, respectively. In serial broth dilution method P. gingivalis and A. actinomycetemcomitans were sensitive until 31.25 μg/ml dilutions. From results of the study, it is suggested that an alcoholic extract of banana peel has antimicrobial activity against P. gingivalis and A. actinomycetemcomitans.

The cyclic-AMP receptor protein (CRP) regulon in Aggregatibacter actinomycetemcomitans includes leukotoxin

PubMed Central

Feuerbacher, Leigh A.; Burgum, Alex; Kolodrubetz, David

2011-01-01

The cyclic-AMP receptor protein (CRP) acts as a global regulatory protein among bacteria. Here, the CRP regulon has been defined in Aggregatibacter actinomycetemcomitans using microarray analysis of A. actinomycetemcomitans strain JP2 wild type cells compared to an isogenic crp deletion mutant. Genes whose expression levels changed at least 2-fold with p ≤ 0.05 were considered significant. Of the 300 genes identified as being CRP-regulated, 139 were CRP-activated, including leukotoxin, with the remaining being CRP-repressed. The 300 genes represent 14.2% of ORFs probed which is significantly higher than what has been reported for CRP regulons in other bacteria. If the CRP-regulated genes are put into 17 functional classes, all 17 categories had at least 1 CRP-regulated gene. Several functional categories, mainly transport and binding proteins and energy metabolism proteins, were disproportionately represented in the CRP-regulated subset of genes relative to their overall representation in the genome. This is similar to the patterns seen in other bacteria. Finally, quantitative RT-PCR was used to show that the leukotoxin RNA levels were repressed 16-fold in the CRP mutant indicating that CRP activates leukotoxin transcription. However, this regulation appears to be acting through another regulatory protein since the leukotoxin promoter, unlike ~129 other promoters of CRP-regulated genes, does not have a match to the consensus CRP binding site. Several candidate genes for this intermediary transcription factor have been identified in the CRP-regulon. PMID:21575705

Rapid identification of oral isolates of Aggregatibacter actinomycetemcomitans obtained from humans and primates by an ultrafast super convection based polymerase chain reaction

PubMed Central

Karched, M.; Furgang, D.; Sawalha, N.; Fine, D.H.

2017-01-01

Aggregatibacter actinomycetemcomitans is a Gram negative oral bacterium associated with localized aggressive periodontitis (LAP). Detection of A. actinomycetemcomitans in clinical samples is routinely done by PCR. Our aim was to develop a rapid and reliable PCR method that can be used as a chair-side tool to detect A. actinomycetemcomitans in clinical samples. Sensitivity and specificity assessment was performed on buccal and plaque samples obtained from 40 adolescents enrolled in an ongoing LAP study by comparing 20 A. actinomycetemcomitans-positive subjects and 20 who were negative. In a second study, A. actinomycetemcomitans presence was tested in oral samples from eighty-six primates that included rhesus monkeys, chimpanzees, marmosets, tamarins and baboons. All samples were processed for detection of A. actinomycetemcomitans by means of culture, conventional PCR (cPCR) and rapid PCR (rPCR) using a Super Convection based AmpXpress thermal cycler (AlphaHelix, Sweden). For human samples, culture, cPCR and rPCR showed perfect agreement. Using this method A. actinomycetemcomitans was detected in 27 of 32 rhesus monkeys, 4 of 8 chimpanzees and 1 of 34 marmosets. Rapidity of AmpXpress thermal cycler, combined with Ready-To-Go PCR beads (GE Life sciences), a quick DNA extraction kit (Epicentre Biotechnologies, Madison, Wisconsin, USA) and a bufferless fast agarose gel system, made it possible to obtain results on A. actinomycetemcomitans detection within 35 min. We conclude that AmpXpress fast PCR can be conveniently used as a chair-side tool for rapid detection of A. actinomycetemcomitans in clinical samples. PMID:22326236

Mlc is a transcriptional activator with a key role in integrating cyclic AMP receptor protein and integration host factor regulation of leukotoxin RNA synthesis in Aggregatibacter actinomycetemcomitans

USDA-ARS?s Scientific Manuscript database

Aggregatibacter actinomycetemcomitans, a periodontal pathogen, synthesizes leukotoxin (LtxA), a protein that helps the bacterium evade the host immune response. Transcription of the ltxA operon is induced during anaerobic growth. The cAMP receptor protein (CRP) indirectly increases ltxA expression...

Real-time quantitative reverse transcription-PCR analysis of expression stability of Aggregatibacter actinomycetemcomitans fimbria-associated gene in response to photodynamic therapy.

PubMed

Pourhajibagher, Maryam; Monzavi, Abbas; Chiniforush, Nasim; Monzavi, Mohammad Moein; Sobhani, Shaghayegh; Shahabi, Sima; Bahador, Abbas

2017-06-01

Aggregatibacter actinomycetemcomitans is an etiological agent of both chronic and aggressive periodontitis. Dissemination of A. actinomycetemcomitans from the oral cavity and initiation of systemic infections has led to new approaches for treatment being needed. In this study, a series of experiments presented investigated the effect of methylene blue (MB)-mediated antimicrobial photodynamic therapy (aPDT) on cell viability and expression of fimbria-associated gene (rcpA) in A. actinomycetemcomitans. To determine the dose-depended effects of aPDT, A. actinomycetemcomitans ATCC 33384 strain photosensitized with MB was irradiated with diode laser following bacterial viability measurements. Cell-surviving assay and expression ratio of rcpA were assessed by colony forming unit and real-time quantitative reverse transcription-PCR (qRT-PCR) assays, respectively. In the current study, MB-mediated aPDT using 100μg/mL showed significant reduction in A. actinomycetemcomitans growth when compared to the control (P<0.05). Sub-lethal dose of aPDT against A. actinomycetemcomitans was 25μg/mL MB at fluency of 93.75J/cm 2 . Sub-lethal dose of aPDT could lead to about four-fold suppression of expression of rcpA. High doses of MB-mediated aPDT could potentially exhibit antimicrobial activity, and the expression of rcpA as an important virulence factor of this strain is reduced in cells surviving aPDT with MB. So, aPDT can be a valuable tool for the treatment of A. actinomycetemcomitans infections. Copyright © 2017 Elsevier B.V. All rights reserved.

Detection of Aggregatibacter actinomycetemcomitans leukotoxin and fimbria-associated protein gene genotypes among periodontitis patients and healthy controls: A case–control study

PubMed Central

Mahalakshmi, Krishnan; Krishnan, Padma; Chandrasekaran, S. C.

2018-01-01

Background: Aggregatibacter actinomycetemcomitans has been reported in higher proportions in subgingival microbiota of individuals with aggressive periodontitis (AgP) compared with those with chronic periodontitis (ChP) and healthy controls. The major virulence factors are the ones that help in colonization and evasion of host's defenses. Hence, this study was aimed to assess the prevalence of A. actinomycetemcomitans 16S rRNA and its virulent genotypes (leukotoxin [lktA] and fimbria-associated protein [fap]). Materials and Methods: In this case– control study We performed periodontal examination and measured probing depth and clinical attachment level (CAL). Subgingival plaque samples from 200 (ChP: n = 128 and AgP: n = 72) periodontitis patients and 200 healthy controls were screened for the presence of A. actinomycetemcomitans 16S rRNA, lktA, and fap genotypes by polymerase chain reaction. The prevalence of genotypes between periodontitis patients and healthy controls was compared with Pearson's Chi-square test. P < 0.05 was considered statistically significant. Results: Mean pocket probing depth and CAL were high as compared to the healthy controls. The prevalence of A. actinomycetemcomitans in ChP (n = 128), AgP (n = 72), and healthy individuals (n = 200) was 32.0%, 61.1%, and 2.5%, respectively. A. actinomycetemcomitans lktA genotype prevalence was 71.8% among periodontitis patients, while A. actinomycetemcomitans fap genotype showed 31.8% prevalence. The prevalence of these genotypes was insignificant in healthy controls. Conclusion: The high odds ratio for A. actinomycetemcomitans prevalence suggests its strong link to periodontitis. Detection of A. actinomycetemcomitans lktA + genotype may be a useful marker for AgP as its prevalence was found to be high in AgP. PMID:29922337

Detection of antimicrobial activity of banana peel (Musa paradisiaca L.) on Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans: An in vitro study

PubMed Central

Kapadia, Suraj Premal; Pudakalkatti, Pushpa S.; Shivanaikar, Sachin

2015-01-01

Introduction and Aim: Banana is used widely because of its nutritional values. In past, there are studies that show banana plant parts, and their fruits can be used to treat the human diseases. Banana peel is a part of banana fruit that also has the antibacterial activity against microorganisms but has not been studied extensively. Since, there are no studies that relate the antibacterial activity of banana peel against periodontal pathogens. Hence, the aim of this study is to determine the antimicrobial activity of banana peel extract on Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans). Material and Methods: Standard strains of P. gingivalis and A. actinomycetemcomitans were used in this study which was obtained from the in-house bacterial bank of Department of Molecular Biology and Immunology at Maratha Mandal's Nathajirao G. Halgekar Institute of Dental Sciences and Research Centre. The banana peel extract was prepared, and the antibacterial activity was assessed using well agar diffusion method and minimum inhibitory concentration was assessed using serial broth dilution method. Results: In the current study, both the tested microorganisms showed antibacterial activity. In well diffusion method, P. gingivalis and A. actinomycetemcomitans showed 15 mm and 12 mm inhibition zone against an alcoholic extract of banana peel, respectively. In serial broth dilution method P. gingivalis and A. actinomycetemcomitans were sensitive until 31.25 μg/ml dilutions. Conclusion: From results of the study, it is suggested that an alcoholic extract of banana peel has antimicrobial activity against P. gingivalis and A. actinomycetemcomitans. PMID:26681854

Identifying genes involved in the interaction of Aggregatibacter actinomycetemcomitans with Maillard reaction products (MRP)

NASA Astrophysics Data System (ADS)

Jaha, Raniah Abdulmohsen

Aggregatibacter (Actinobacillus) actinomycelemcomitcrns is a gram-negative bacterium that is a facultative anaerobe which can grow in either aerobic or anaerobic conditions. The bacteria cause localized aggressive periodontitis that can result in the loss of teeth and endocarditis, which is an infection of the heart valves. A rich medium is an essential requirement for its growth. There arc some difficulties associated with growing the bacteria as they easily switch from the rough to smooth phenotype under no specific conditions. The bacteria start to lose viability after about 19 hours of growth in broth or about three days on plates. Colonies in the dense part of the streak on plates die earlier. It was shown that acid secreted by the colonies is responsible for the loss of viability as the bacteria are extremely sensitive to low pH. Autoclaving the growth medium for A. actinomycetemcomitans causes the bacteria to grow slowly because of the formation of Maillard reaction products (MRPs). A method has been developed to make the A. actinomycetemcomitans growth medium using the microwave instead of the autoclave. This method produces much less of the inhibitory product since the heating time is only six minutes, compared to more than an hour when using the autoclave. Two approaches were sought in this research. The first approach was the identification of genes responsible for the interaction between the MRP and A. actinomycetemcomitans. The gene responsible for this interaction was found to be a Lys M protein which is found in many genes responsible for the cell wall integrity. The second approach was to develop a new drug made of glucose and lysine with a minimum inhibitory concentration as 75mM.

Screen for leukotoxin mutants in Aggregatibacter actinomycetemcomitans: genes of the phosphotransferase system are required for leukotoxin biosynthesis.

PubMed

Isaza, Maria P; Duncan, Matthew S; Kaplan, Jeffrey B; Kachlany, Scott C

2008-08-01

Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans is a pathogen that causes localized aggressive periodontitis and extraoral infections including infective endocarditis. Recently, we reported that A. actinomycetemcomitans is beta-hemolytic on certain growth media due to the production of leukotoxin (LtxA). Based on this observation and our ability to generate random transposon insertions in A. actinomycetemcomitans, we developed and carried out a rapid screen for LtxA mutants. Using PCR, we mapped several of the mutations to genes that are known or predicted to be required for LtxA production, including ltxA, ltxB, ltxD, and tdeA. In addition, we identified an insertion in a gene previously not recognized to be involved in LtxA biosynthesis, ptsH. ptsH encodes the protein HPr, a phosphocarrier protein that is part of the sugar phosphotransferase system. HPr results in the phosphorylation of other proteins and ultimately in the activation of adenylate cyclase and cyclic AMP (cAMP) production. The ptsH mutant showed only partial hemolysis on blood agar and did not produce LtxA. The phenotype was complemented by supplying wild-type ptsH in trans, and real-time PCR analysis showed that the ptsH mutant produced approximately 10-fold less ltxA mRNA than the wild-type strain. The levels of cAMP in the ptsH mutant were significantly lower than in the wild-type strain, and LtxA production could be restored by adding exogenous cAMP to the culture.

Al(III), Pd(II), and Zn(II) phthalocyanines for inactivation of dental pathogen Aggregatibacter actinomycetemcomitans as planktonic and biofilm-cultures

NASA Astrophysics Data System (ADS)

Kussovski, V.; Mantareva, V.; Angelov, I.; Avramov, L.; Popova, E.; Dimitrov, S.

2012-06-01

The Gram-negative, oral bacterium Aggregatibacter actinomycetemcomitans has been implicated as the causative agent of several forms of periodontal disease in humans. The new periodontal disease treatments are emergence in order to prevent infection progression. Antimicrobial photodynamic therapy (a-PDT) can be a useful tool for this purpose. It involves the use of light of specific wavelength to activate a nontoxic photosensitizing agent in the presence of oxygen for eradication of target cells, and appears effective in photoinactivation of microorganisms. The phthalocyanine metal complexes of Pd(II)- (PdPcC) and Al(III)- (AlPc1) were evaluated as photodynamic sensitizers towards a dental pathogen A. actinomycetemcomitans in comparison to the known methylpyridyloxy-substituted Zn(II) phthalocyanine (ZnPcMe). The planktonic and biofilm-cultivated species of A. actinomycetemcomitans were treated. The photophysical results showed intensive and far-red absorbance with high tendency of aggregation for Pd(II)-phthalocyanine. The dark toxicities of both photosensitizers were negligible at concentrations used (< 0.5 log decrease of viable cells). The photodynamic response for planktonic cultured bacteria was full photoinactivation after a-PDT with ZnPcMe. In case of the newly studied complexes, the effect was lower for PdPcC (4 log) as well as for AlPc1 (1.5-2 log). As it is known the bacterial biofilms were more resistant to a-PDT, which was confirmed for A. actinomycetemcomitans biofilms with 3 log reductions of viable cells after treatment with ZnPcMe and approximately 1 log reduction of biofilms after PdPcC and AlPc1. The initial results suggest that a-PDT can be useful for effective inactivation of dental pathogen A. actinomycetemcomitans.

Outer membrane components of the Tad (tight adherence) secreton of Aggregatibacter actinomycetemcomitans.

PubMed

Clock, Sarah A; Planet, Paul J; Perez, Brenda A; Figurski, David H

2008-02-01

Prokaryotic secretion relies on proteins that are widely conserved, including NTPases and secretins, and on proteins that are system specific. The Tad secretion system in Aggregatibacter actinomycetemcomitans is dedicated to the assembly and export of Flp pili, which are needed for tight adherence. Consistent with predictions that RcpA forms the multimeric outer membrane secretion channel (secretin) of the Flp pilus biogenesis apparatus, we observed the RcpA protein in multimers that were stable in the presence of detergent and found that rcpA and its closely related homologs form a novel and distinct subfamily within a well-supported gene phylogeny of the entire secretin gene superfamily. We also found that rcpA-like genes were always linked to Aggregatibacter rcpB- or Caulobacter cpaD-like genes. Using antisera, we determined the localization and gross abundances of conserved (RcpA and TadC) and unique (RcpB, RcpC, and TadD) Tad proteins. The three Rcp proteins (RcpA, RcpB, and RcpC) and TadD, a putative lipoprotein, localized to the bacterial outer membrane. RcpA, RcpC, and TadD were also found in the inner membrane, while TadC localized exclusively to the inner membrane. The RcpA secretin was necessary for wild-type abundances of RcpB and RcpC, and TadC was required for normal levels of all three Rcp proteins. TadC abundance defects were observed in rcpA and rcpC mutants. TadD production was essential for wild-type RcpA and RcpB abundances, and RcpA did not multimerize or localize to the outer membrane without the expression of TadD. These data indicate that membrane proteins TadC and TadD may influence the assembly, transport, and/or function of individual outer membrane Rcp proteins.

PCR detection of Streptococcus mutans and Aggregatibacter actinomycetemcomitans in dental plaque samples from Haitian adolescents.

PubMed

Psoter, Walter J; Ge, Yao; Russell, Stefanie L; Chen, Zhou; Katz, Ralph V; Jean-Charles, Germain; Li, Yihong

2011-08-01

Streptococcus mutans and Aggregatibacter actinomycetemcomitans are oral pathogens associated with dental caries and periodontitis, respectively. The aim of this study was to determine the colonization of these two microorganisms in the dental plaque of a group of Haitian adolescents using two different polymerase chain reaction (PCR) methods, standard PCR, and quantitative real-time PCR (qPCR) assays. Fifty-four pooled supra-gingival plaque samples and 98 pooled sub-gingival plaque samples were obtained from 104 12- to19-year-old rural-dwelling Haitians. The total genomic DNA of bacteria was isolated from these samples, and all participants also received caries and periodontal examinations. Caries prevalence was 42.2%, and the mean decayed, missing, and filled surface (DMFS) was 2.67 ± 5.3. More than half of the adolescents (53.3%) experienced periodontal pockets (Community Periodontal Index score ≥3). S. mutans was detected in 67.3% by qPCR and 38.8% by PCR of the supra-gingival plaque samples (p < 0.01), and 36.6% by qPCR and 8.1% by PCR of the sub-gingival samples (p < 0.01). A. actinomycetemcomitans was detected in 85.1% by qPCR and 44.0% by PCR of the sub-gingival samples (p < 0.01), but the prevalence was similar, 67.3% by qPCR and 59.2% by PCR, in the supra-gingival plaque samples. Neither age nor gender was significantly correlated to the bacterial colonization. The results demonstrated a moderate-to-high prevalence of S. mutans and A. actinomycetemcomitans in the Haitian adolescent population, and qPCR is more sensitive than standard PCR in field conditions. These findings suggest that qPCR should be considered for field oral epidemiologic studies and may be necessary in investigations having major logistic challenges.

Are there specific benefits of amoxicillin plus metronidazole in Aggregatibacter actinomycetemcomitans-associated periodontitis? Double-masked, randomized clinical trial of efficacy and safety.

PubMed

Mombelli, Andrea; Cionca, Norbert; Almaghlouth, Adnan; Décaillet, Fabien; Courvoisier, Delphine S; Giannopoulou, Catherine

2013-06-01

It has been suggested that prescription of amoxicillin plus metronidazole in the context of periodontal therapy should be limited to patients with specific microbiologic profiles, especially those testing positive for Aggregatibacter actinomycetemcomitans. The main purpose of this analysis is to determine if patients positive for A. actinomycetemcomitans with moderate to advanced periodontitis benefit specifically from amoxicillin plus metronidazole given as an adjunct to full-mouth scaling and root planing. This is a double-masked, placebo-controlled, randomized longitudinal study including 41 participants who were positive for A. actinomycetemcomitans and 41 participants who were negative for A. actinomycetemcomitans. All 82 patients received full-mouth periodontal debridement performed within 48 hours. Patients then received either systemic antibiotics (375 mg amoxicillin and 500 mg metronidazole, three times daily) or placebo for 7 days. The primary outcome variable was persistence of sites with a probing depth (PD) >4 mm and bleeding on probing (BOP) at the 3-month reevaluation. Using multilevel logistic regression, the effect of the antibiotics was analyzed according to the following factors (interaction effect): A. actinomycetemcomitans-positive or -negative at baseline, sex, age, smoking, tooth being a molar, and interdental location. At reevaluation, participants in the test group had significantly fewer sites with a persisting PD >4 mm and BOP than control patients (P <0.01). Being A. actinomycetemcomitans-positive or -negative did not change the effect of the antibiotics. Patients benefited from the antibiotics irrespective of sex, age, or smoking status. Molars benefited significantly more from the antibiotics than non-molars (P for interaction effect = 0.03). Patients who were positive for A. actinomycetemcomitans had no specific benefit from amoxicillin plus metronidazole. Sites on molars benefited significantly more from the antibiotics than non

Screen for Leukotoxin Mutants in Aggregatibacter actinomycetemcomitans: Genes of the Phosphotransferase System Are Required for Leukotoxin Biosynthesis▿

PubMed Central

Isaza, Maria P.; Duncan, Matthew S.; Kaplan, Jeffrey B.; Kachlany, Scott C.

2008-01-01

Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans is a pathogen that causes localized aggressive periodontitis and extraoral infections including infective endocarditis. Recently, we reported that A. actinomycetemcomitans is beta-hemolytic on certain growth media due to the production of leukotoxin (LtxA). Based on this observation and our ability to generate random transposon insertions in A. actinomycetemcomitans, we developed and carried out a rapid screen for LtxA mutants. Using PCR, we mapped several of the mutations to genes that are known or predicted to be required for LtxA production, including ltxA, ltxB, ltxD, and tdeA. In addition, we identified an insertion in a gene previously not recognized to be involved in LtxA biosynthesis, ptsH. ptsH encodes the protein HPr, a phosphocarrier protein that is part of the sugar phosphotransferase system. HPr results in the phosphorylation of other proteins and ultimately in the activation of adenylate cyclase and cyclic AMP (cAMP) production. The ptsH mutant showed only partial hemolysis on blood agar and did not produce LtxA. The phenotype was complemented by supplying wild-type ptsH in trans, and real-time PCR analysis showed that the ptsH mutant produced approximately 10-fold less ltxA mRNA than the wild-type strain. The levels of cAMP in the ptsH mutant were significantly lower than in the wild-type strain, and LtxA production could be restored by adding exogenous cAMP to the culture. PMID:18541661

Pathogenicity of the highly leukotoxic JP2 clone of Aggregatibacter actinomycetemcomitans and its geographic dissemination and role in aggressive periodontitis

PubMed Central

Haubek, Dorte; Johansson, Anders

2014-01-01

For decades, Aggregatibacter actinomycetemcomitans has been associated with aggressive forms of periodontitis in adolescents. In the middle of the 1990s, a specific JP2 clone of A. actinomycetemcomitans, belonging to the cluster of serotype b strains of A. actinomycetemcomitans and having a number of other characteristics, was found to be strongly associated with aggressive forms of periodontitis, particularly in North Africa. Although several longitudinal studies still point to the bacterial species, A. actinomycetemcomitans as a risk factor of aggressive periodontitis, it is now also widely accepted that the highly leukotoxic JP2 clone of A. actinomycetemcomitans is implicated in rapidly progressing forms of aggressive periodontitis. The JP2 clone strains are highly prevalent in human populations living in Northern and Western parts of Africa. These strains are also prevalent in geographically widespread populations that have originated from the Northwest Africa. Only sporadic signs of a dissemination of the JP2 clone strains to non-African populations have been found despite Africans living geographically widespread for hundreds of years. It remains an unanswered question if a particular host tropism exists as a possible explanation for the frequent colonization of the Northwest African population with the JP2 clone. Two exotoxins of A. actinomycetemcomitans are known, leukotoxin (LtxA) and cytolethal distending toxin (Cdt). LtxA is able to kill human immune cells, and Cdt can block cell cycle progression in eukaryotic cells and thus induce cell cycle arrest. Whereas the leukotoxin production is enhanced in JP2 clone strains thus increasing the virulence potential of A. actinomycetemcomitans, it has not been possible so far to demonstrate such a role for Cdt. Lines of evidence have led to the understanding of the highly leukotoxic JP2 clone of A. actinomycetemcomitans as an aetiological factor of aggressive periodontitis. Patients, who are colonized with the JP2

Transcriptional Regulation of Aggregatibacter actinomycetemcomitans lsrACDBFG and lsrRK Operons and Their Role in Biofilm Formation

PubMed Central

Torres-Escobar, Ascención; Juárez-Rodríguez, María Dolores; Lamont, Richard J.

2013-01-01

Autoinducer-2 (AI-2) is required for biofilm formation and virulence of the oral pathogen Aggregatibacter actinomycetemcomitans, and we previously showed that lsrB codes for a receptor for AI-2. The lsrB gene is expressed as part of the lsrACDBFG operon, which is divergently transcribed from an adjacent lsrRK operon. In Escherichia coli, lsrRK encodes a repressor and AI-2 kinase that function to regulate lsrACDBFG. To determine if lsrRK controls lsrACDBFG expression and influences biofilm growth of A. actinomycetemcomitans, we first defined the promoters for each operon. Transcriptional reporter plasmids containing the 255-bp lsrACDBFG-lsrRK intergenic region (IGR) fused to lacZ showed that essential elements of lsrR promoter reside 89 to 255 bp upstream from the lsrR start codon. Two inverted repeat sequences that represent potential binding sites for LsrR and two sequences resembling the consensus cyclic AMP receptor protein (CRP) binding site were identified in this region. Using electrophoretic mobility shift assay (EMSA), purified LsrR and CRP proteins were shown to bind probes containing these sequences. Surprisingly, the 255-bp IGR did not contain the lsrA promoter. Instead, a fragment encompassing nucleotides +1 to +159 of lsrA together with the 255-bp IGR was required to promote lsrA transcription. This suggests that a region within the lsrA coding sequence influences transcription, or alternatively that the start codon of A. actinomycetemcomitans lsrA has been incorrectly annotated. Transformation of ΔlsrR, ΔlsrK, ΔlsrRK, and Δcrp deletion mutants with lacZ reporters containing the lsrA or lsrR promoter showed that LsrR negatively regulates and CRP positively regulates both lsrACDBFG and lsrRK. However, in contrast to what occurs in E. coli, deletion of lsrK had no effect on the transcriptional activity of the lsrA or lsrR promoters, suggesting that another kinase may be capable of phosphorylating AI-2 in A. actinomycetemcomitans. Finally, biofilm

Inverse Association of Plasma IgG Antibody to Aggregatibacter actinomycetemcomitans and High C-Reactive Protein Levels in Patients with Metabolic Syndrome and Periodontitis.

PubMed

Thanakun, Supanee; Pornprasertsuk-Damrongsri, Suchaya; Gokyu, Misa; Kobayashi, Hiroaki; Izumi, Yuichi

2016-01-01

The association between clinically diagnosed periodontitis, a common chronic oral infection, and metabolic syndrome has been previously reported. The aim of this study was to investigate the association of plasma IgG levels against Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia, C-reactive protein, and periodontal status with metabolic syndrome. Plasma IgG levels and C-reactive protein were measured by enzyme-linked immunosorbent assay, and salivary levels of A. actinomycetemcomitans and P. gingivalis were determined by quantitative real-time polymerase chain reaction. Among 127 individuals aged 35-76 years, 57 participants had metabolic syndrome and severe periodontitis, 25 had metabolic syndrome and an absence of severe periodontitis, 17 healthy individuals had severe periodontitis, and 28 healthy individuals were without severe periodontitis. Patients with metabolic syndrome had reduced humoral immune response to A. actinomycetemcomitans (p = 0.008), regardless of their salivary levels or periodontitis status compared with healthy participants. The IgG antibody response to P. gingivalis, regardless of their salivary levels or participants' health condition, was significantly higher in severe periodontitis patients (p<0.001). Plasma IgG titers for P. intermedia were inconsistent among metabolic syndrome or periodontal participants. Our results indicate that the presence of lower levels of IgG antibodies to A. actinomycetemcomitans (OR = 0.1; 95%CI 0.0-0.7), but not P. gingivalis, a severe periodontitis status (OR = 7.8; 95%CI 1.1-57.0), high C-reactive protein levels (OR = 9.4; 95%CI 1.0-88.2) and body mass index (OR = 3.0; 95%CI 1.7-5.2), are associated with the presence of metabolic syndrome. The role of the decreased IgG antibody response to A. actinomycetemcomitans, increased C-reactive protein levels on the association between periodontal disease and metabolic syndrome in a group of Thai patients is suggested.

Determination of antibacterial activity of green coffee bean extract on periodontogenic bacteria like Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans: An in vitro study.

PubMed

Bharath, Nagaraj; Sowmya, Nagur Karibasappa; Mehta, Dhoom Singh

2015-01-01

The aim of this study was to evaluate the antibacterial activity of pure green coffee bean extract on periodonto pathogenic bacteria Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Aggregatibacter actinomycetemcomitans (Aa). Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBC) were used to assess the antibacterial effect of pure green coffee bean extract against periodonto pathogenic bacteria by micro dilution method and culture method, respectively. MIC values of Pg, Pi and Aa were 0.2 μg/ml whereas Fn showed sensitive at concentration of 3.125 μg/ml. MBC values mirrors the values same as that of MIC. Antimicrobial activity of pure green coffee bean extract against Pg, Pi, Fn and Aa suggests that it could be recommended as an adjunct to mechanical therapy in the management of periodontal disease.

Determination of antibacterial activity of green coffee bean extract on periodontogenic bacteria like Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans: An in vitro study

PubMed Central

Bharath, Nagaraj; Sowmya, Nagur Karibasappa; Mehta, Dhoom Singh

2015-01-01

Background: The aim of this study was to evaluate the antibacterial activity of pure green coffee bean extract on periodonto pathogenic bacteria Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn) and Aggregatibacter actinomycetemcomitans (Aa). Materials and Methods: Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBC) were used to assess the antibacterial effect of pure green coffee bean extract against periodonto pathogenic bacteria by micro dilution method and culture method, respectively. Results: MIC values of Pg, Pi and Aa were 0.2 μg/ml whereas Fn showed sensitive at concentration of 3.125 μg/ml. MBC values mirrors the values same as that of MIC. Conclusion: Antimicrobial activity of pure green coffee bean extract against Pg, Pi, Fn and Aa suggests that it could be recommended as an adjunct to mechanical therapy in the management of periodontal disease. PMID:26097349

Photodynamic therapy of Curcuma longa extract stimulated with blue light against Aggregatibacter actinomycetemcomitans.

PubMed

Saitawee, Darika; Teerakapong, Aroon; Morales, Noppawan Phumala; Jitprasertwong, Paiboon; Hormdee, Doosadee

2018-06-01

Curcumin, one of an established curcuminoid substances extracted from Curcuma longa, has been used as a photosensitizer (PS) in photodynamic therapy (PDT). Curcuminoid substances has been reported to have benefits in treating dental chronic infection and inflammation diseases, such as chronic periodontitis. The purpose of this study was to find the optimum concentration of Curcuma longa (CL) extract, containing all curcuminoid substances, and the power density of blue light (BL) in photodynamic therapy against periodontally pathogenic bacteria, A. actinomycetemcomitans. Antibacterial activity of various concentrations of CL extract against A. actinomycetemcomitans was determined. Exponentially growing bacteria were combined with 2-fold dilution of CL extract solution ranging from 25 to 0.098 μg/ml. Co-culture bacteria treated with 0.12% chlorhexidine (CHX) served as the positive control. The effect of photostimulation with light emitting diode (LED) 420-480 nm at 16.8 J/cm 2 for 1 min on the selected concentration of CL extract was examined. Bacteria viability was determined by plate counting technique. In addition, production of free radicals was tested by electron spin resonance spectroscope (ESR) with 5,5-dimethyl-1-pyrroline N-oxide (DMPO). The antibacterial activity of CL extract was dose dependent. Without BL, 25 μg/ml CL extract showed 6.03 ± 0.39 log 10 A. actinomycetemcomitans. Interestingly, the combination of BL and 0.78 μg/ml CL extract solution showed complete absence of A. actinomycetemcomitans. Peak signal intensity of hydroxyl radical production was also detected with the combination of BL and CL. CL extract not only had antimicrobial activity but also could be used as an effective PS when stimulated with BL in PDT. The optimal antibacterial effect of CL extract with BL was equal to the standard oral disinfectant, 0.12% CHX. Copyright © 2018 Elsevier B.V. All rights reserved.

The mechanism of Jurkat cells apoptosis induced by Aggregatibacter actinomycetemcomitans cytolethal distending toxin.

PubMed

Chen, Hui-Ping; Li, Lu; Chen, Xu; Yang, Mi-Fang; Ye, Yu; Wang, Xiao-Qian; Xu, Yan

2017-06-01

Cytolethal distending toxin (CDT) which is produced by Aggregatibacter actinomycetemcomitans causes apoptosis in lymphocytes. But the specific mechanism is not clear. The aim of our research was to investigate the effect and mechanism during this process. The wild-type CdtA, CdtB, CdtC (CdtA W , CdtB W , CdtC W ) and mutant CdtB (CdtB M ) were expressed and purified respectively and the purity of each subunit was examined by BandScan software. And the type I deoxyribonuclease and PI-3,4,5-triphosphate (PI-3,4,5-P3, PIP3) phosphatase activity were detected by DNA agarose gel electrophoresis and enzyme-linked immunosorbent assay respectively. The cell apoptosis rates were analyzed by flow cytometry. The morphological changes of apoptosis cells were observed by confocal laser scanning microscopy. The protein expression of Bax and Bcl-2 was examined by western blot. Differentially expressed apoptosis-related proteins were identified based on isobaric tags for relative and absolute quantitation technology. In the present study we found that: (i) recombinant wild-type CdtA, CdtB and CdtC (CdtA W , CdtB W , CdtC W ) and mutant CdtB (CdtB M ) were correctly expressed and the purity of each protein was higher than 80%, (ii) the average apoptosis rate in wild-type CDT (CDT W ) treated groups was 50.54%, which was significantly higher than the controls (4.71%) and mutant CDT (CDT M ) treated groups (5.58%) (p < 0.05), (iii) morphological changes of apoptosis were observed in CDT W treated cells, (iv) the expression of Bax protein was significantly increased in CDT W treated cells, while Bcl-2 protein expression was significantly decreased, (v) 17 apoptosis-related proteins were expressed differentially, among which 10 proteins (SMNDC1, TNFRSF10B, UBE2I, ITM2A, CASP3, P53, EIF1, TCF3, HMGN5, CASP8) were up-regulated and 7 proteins (RRM2, TPX2, KIF11, NUCKS1, TOP2A, XRCC1, PTPLAD1, RRM2) were down-regulated, (vi) one possible apoptotic pathway [Ubc9 (UBE2I)/P53/DR5 (TNFRSF

Classification, Identification, and Clinical Significance of Haemophilus and Aggregatibacter Species with Host Specificity for Humans

PubMed Central

2014-01-01

SUMMARY The aim of this review is to provide a comprehensive update on the current classification and identification of Haemophilus and Aggregatibacter species with exclusive or predominant host specificity for humans. Haemophilus influenzae and some of the other Haemophilus species are commonly encountered in the clinical microbiology laboratory and demonstrate a wide range of pathogenicity, from life-threatening invasive disease to respiratory infections to a nonpathogenic, commensal lifestyle. New species of Haemophilus have been described (Haemophilus pittmaniae and Haemophilus sputorum), and the new genus Aggregatibacter was created to accommodate some former Haemophilus and Actinobacillus species (Aggregatibacter aphrophilus, Aggregatibacter segnis, and Aggregatibacter actinomycetemcomitans). Aggregatibacter species are now a dominant etiology of infective endocarditis caused by fastidious organisms (HACEK endocarditis), and A. aphrophilus has emerged as an important cause of brain abscesses. Correct identification of Haemophilus and Aggregatibacter species based on phenotypic characterization can be challenging. It has become clear that 15 to 20% of presumptive H. influenzae isolates from the respiratory tracts of healthy individuals do not belong to this species but represent nonhemolytic variants of Haemophilus haemolyticus. Due to the limited pathogenicity of H. haemolyticus, the proportion of misidentified strains may be lower in clinical samples, but even among invasive strains, a misidentification rate of 0.5 to 2% can be found. Several methods have been investigated for differentiation of H. influenzae from its less pathogenic relatives, but a simple method for reliable discrimination is not available. With the implementation of identification by matrix-assisted laser desorption ionization–time of flight mass spectrometry, the more rarely encountered species of Haemophilus and Aggregatibacter will increasingly be identified in clinical microbiology

Structural and Genetic Analyses of O Polysaccharide from Actinobacillus actinomycetemcomitans Serotype f

PubMed Central

Kaplan, Jeffrey B.; Perry, Malcolm B.; MacLean, Leann L.; Furgang, David; Wilson, Mark E.; Fine, Daniel H.

2001-01-01

The oral bacterium Actinobacillus actinomycetemcomitans is implicated as a causative agent of localized juvenile periodontitis (LJP). A. actinomycetemcomitans is classified into five serotypes (a to e) corresponding to five structurally and antigenically distinct O polysaccharide (O-PS) components of their respective lipopolysaccharide molecules. Serotype b has been reported to be the dominant serotype isolated from LJP patients. We determined the lipopolysaccharide O-PS structure from A. actinomycetemcomitans CU1000, a strain isolated from a 13-year-old African-American female with LJP which had previously been classified as serotype b. The O-PS of strain CU1000 consisted of a trisaccharide repeating unit composed of l-rhamnose and 2-acetamido-2-deoxy-d-galactose (molar ratio, 2:1) with the structure →2)-α-l-Rhap-(1–3)-2-O-(β-d-GalpNAc)-α-l-Rhap-(1→. O-PS from strain CU1000 was structurally and antigenically distinct from the O-PS molecules of the five known A. actinomycetemcomitans serotypes. Strain CU1000 was mutagenized with transposon IS903φkan, and three mutants that were deficient in O-PS synthesis were isolated. All three transposon insertions mapped to a single 1-kb region on the chromosome. The DNA sequence of a 13.1-kb region surrounding these transposon insertions contained a cluster of 14 open reading frames that was homologous to gene clusters responsible for the synthesis of A. actinomycetemcomitans serotype b, c, and e O-PS antigens. The CU1000 gene cluster contained two genes that were not present in serotype-specific O-PS antigen clusters of the other five known A. actinomycetemcomitans serotypes. These data indicate that strain CU1000 should be assigned to a new A. actinomycetemcomitans serotype, designated serotype f. A PCR assay using serotype-specific PCR primers showed that 3 out of 20 LJP patients surveyed (15%) harbored A. actinomycetemcomitans strains carrying the serotype f gene cluster. The finding of an A

Characterization of A. actinomycetemcomitans strains in subgingival samples from periodontitis subjects in Morocco.

PubMed

Mínguez, M; Ennibi, O K; Pousa, X; Lakhdar, L; Abdellaoui, L; Sánchez, M; Sanz, M; Herrera, D

2016-09-01

Aggregatibacter actinomycetemcomitans, specially its highly leucotoxic strain (JP2 clone), represents an etiological factor for the onset and progression of aggressive types of periodontitis. The aims of this investigation were to investigate the most relevant periodontal pathogens in the subgingival microbiota of periodontitis patients from Morocco and to describe the clinical and microbiological characteristics of subjects positive for A. actinomycetemcomitans, including serotype, leukotoxin gene, and operon of the cytolethal distending toxin (cdt) distribution. In consecutive Moroccan subjects diagnosed of periodontitis, subgingival samples were taken and processed by culture. From the positive samples for A. actinomycetemcomitans, one to three isolates were subcultured and characterized by means of polymerase chain reaction (PCR), assessing their specific serotype distribution, the variation in the sequences of the leukotoxin gene, and the operon of the cdt. Twenty-one (35.6 %) out of 59 periodontitis patients harbored A. actinomycetemcomitans. These patients demonstrated statistically significant deeper pockets (p = 0.035) and higher proportions of P. micra (p = 0.045) than did the negative group. The 39 studied isolates were serotype "b"; in 16 out of 17 patients, there was mono-colonization with this serotype. Five isolates, from two patients, presented the 530-bp deletion in the leukotoxin's promoter region. Thirty-two isolates (78 % of the strains) were cdt-positive. A. actinomycetemcomitans was frequently found (35.6 %) in our sample. All strains were serotype "b," and most (78 %) were also cdt-positive. The JP2 strain type was only detected in 12.2 % of the strains. A. actinomycetemcomitans can be frequently found in Morocco. This fact can influence the therapeutic approach of this type of patients.

Mlc Is a Transcriptional Activator with a Key Role in Integrating Cyclic AMP Receptor Protein and Integration Host Factor Regulation of Leukotoxin RNA Synthesis in Aggregatibacter actinomycetemcomitans

PubMed Central

Childress, Catherine; Feuerbacher, Leigh A.; Phillips, Linda; Burgum, Alex

2013-01-01

Aggregatibacter actinomycetemcomitans, a periodontal pathogen, synthesizes leukotoxin (LtxA), a protein that helps the bacterium evade the host immune response. Transcription of the ltxA operon is induced during anaerobic growth. The cyclic AMP (cAMP) receptor protein (CRP) indirectly increases ltxA expression, but the intermediary regulator is unknown. Integration host factor (IHF) binds to and represses the leukotoxin promoter, but neither CRP nor IHF is responsible for the anaerobic induction of ltxA RNA synthesis. Thus, we have undertaken studies to identify other regulators of leukotoxin transcription and to demonstrate how these proteins work together to modulate leukotoxin synthesis. First, analyses of ltxA RNA expression from defined leukotoxin promoter mutations in the chromosome identify positions −69 to −35 as the key control region and indicate that an activator protein modulates leukotoxin transcription. We show that Mlc, which is a repressor in Escherichia coli, functions as a direct transcriptional activator in A. actinomycetemcomitans; an mlc deletion mutant reduces leukotoxin RNA synthesis, and recombinant Mlc protein binds specifically at the −68 to −40 region of the leukotoxin promoter. Furthermore, we show that CRP activates ltxA expression indirectly by increasing the levels of Mlc. Analyses of Δmlc, Δihf, and Δihf Δmlc strains demonstrate that Mlc can increase RNA polymerase (RNAP) activity directly and that IHF represses ltxA RNA synthesis mainly by blocking Mlc binding. Finally, a Δihf Δmlc mutant still induces ltxA during anaerobic growth, indicating that there are additional factors involved in leukotoxin transcriptional regulation. A model for the coordinated regulation of leukotoxin transcription is presented. PMID:23475968

OCCURRENCE OF AGGREGATIBACTER ACTINOMYCETEMCOMITANS IN BRAZILIAN INDIANS FROM UMUTINA RESERVATION, MATO GROSSO, BRAZIL

PubMed Central

Vieira, Evanice Menezes Marçal; Raslan, Suzane A.; Wahasugui, Thais Cristina; Avila-Campos, Mario Julio; Marvulle, Valdecir; Gaetti-Jardim, Elerson

2009-01-01

A ggregatibacter actinomycetemcomitans is associated with periodontal disease, especially localized aggressive periodontitis, produces a potent leukotoxin and its distribution is influenced by ethnic characteristics of the population. Objective: Using culture and polymerase chain reaction (PCR) techniques, this study evaluated the occurrence of this microorganism and the distribution of leukotoxic strains isolated from Indians belonging to the Umutima Reservation, Mato Grosso, Brazil. Material and Methods: Forty-eight native Brazilians with gingivitis and 38 with chronic periodontitis, belonging to Umutina, Paresi, Bororo, Bakairi, Kayabi, Irantxe, Nambikwara and Terena ethnicities, were studied. Subgingival, supragingival and saliva samples of each patient were collected and transferred to VMGA III medium and to ultra pure Milli Q water. Bacteria were grown on TSBV agar and incubated in anaerobiosis (90% N2 + 10% CO2) at 37°C for 72 h. The presence of the ltx promoter was determined by PCR, and a 530 bp deletion in the promoter was evaluated by using specific primers. Results: A. actinomycetemcomitans was isolated from 8.33% of saliva, supragingival and subgingival samples from patients with gingivitis and from 18.42% of saliva and supragingival biofilm, and 26.32% subgingival biofilm from patients with chronic periodontitis. By PCR, the bacterial DNA was detected in 8.33% of saliva, supragingival and subgingival biofilms from patients with gingivitis and from 23.68% of saliva, 28.95% supragingival biofilm and 34.21% subgingival biofilm from patients with periodontitis. All strains were grouped as non-JP2 clones based on the absence of deletion in the leukotoxin promoter. Differences among the microbial and clinical parameters in patients were analyzed by using the Mann-Whitney, Chi-square or Fisher's exact tests. Conclusions: The present results suggest that A. actinomycetemcomitans can be related to the attachment loss in this population, but the presence of

Absolute quantification of Aggregatibacter actinomycetemcomitans in patients carrying haplotypes associated with susceptibility to chronic periodontitis: multifaceted evaluation with periodontitis covariants.

PubMed

Cirelli, Thamiris; Finoti, Livia S; Corbi, Sâmia C T; Anovazzi, Giovana; Nepomuceno, Rafael; Orrico, Silvana R P; Cirelli, Joni A; Mayer, Márcia P A; Scarel-Caminaga, Raquel M

2017-09-29

This study aimed to evaluate the association between haplotypes in the interleukin 8 (IL8) and IL4 genes previously associated to chronic periodontitis (CP) and the levels of Aggregatibacter actinomycetemcomitans (A.a.) in subgingival sites of patients with and without CP. Moreover, multifaceted evaluations were made to search associations among patients' genetic background with the A.a. levels and previous clinical/immunological/microbiological findings. Subgingival sites (n = 596) of 104 patients were divided into susceptible to CP by the IL8 haplotype ATC/TTC (IL8+); non-susceptible to CP by the IL8 AGT/TTC (IL8-); susceptible to CP by the IL4 TCI/CCI (IL4+); protection against CP by the IL4 TTD/CTI (IL4-). Subgingival biofilm samples from diseased and healthy sites of CP patients and from control sites of health patients were obtained for absolute quantification of A.a. by quantitative real-time polymerase chain reaction. For diseased sites, samples were collected before and 45 days after periodontal treatment. The IL4 but not the IL8 haplotypes were associated with levels of A.a. (in both periods). After periodontal treatment, higher levels of A.a. were found in subgingival sites of (IL4-) patients, and higher levels of IL-4 were associated with deeper probing pockets in these same patients. Significant correlations were found among genetic (patients carrying IL8 or IL4 haplotypes), microbiological and immunological data showing the interrelationship of different factors in the CP. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Aggregatibacter actinomycetemcomitans regulates the expression of integrins and reduces cell adhesion via integrin α5 in human gingival epithelial cells.

PubMed

Kochi, Shinsuke; Yamashiro, Keisuke; Hongo, Shoichi; Yamamoto, Tadashi; Ugawa, Yuki; Shimoe, Masayuki; Kawamura, Mari; Hirata-Yoshihara, Chiaki; Ideguchi, Hidetaka; Maeda, Hiroshi; Takashiba, Shogo

2017-12-01

Gingival epithelial cells form a physiological barrier against bacterial invasion. Excessive bacterial invasion destroys the attachment between the tooth surface and the epithelium, resulting in periodontitis. Integrins play a significant role in cell attachment; therefore, we hypothesized that bacterial infection might decrease the expressions of these integrins in gingival epithelial cells, resulting in reduced cell adhesion. Immortalized human gingival epithelial cells were co-cultured with Aggregatibacter actinomycetemcomitans Y4 (Aa Y4), and the gene expression levels of IL-8, proliferating cell nuclear antigen (PCNA), and integrins (α2, α3, α5, β4, and β6) were measured using quantitative reverse transcription polymerase chain reaction. Expression of PCNA and integrins, except integrin α5, was significantly downregulated, while expression of IL-8 and integrin α5 was significantly upregulated in the cells co-cultured with Aa Y4. The number of adherent cells significantly decreased when co-cultured with Aa Y4, as determined using cell adhesion assays. In the cells co-cultured with Aa Y4 and an integrin α5 neutralizing antibody, there was no effect on the expression of IL-8 and PCNA, while the expressions of integrins α2, α3, β4, and β6, and the number of adherent cells did not decrease. The number of invading bacteria in the cells was reduced in the presence of the antibody and increased in the presence of TLR2/4 inhibitor. Therefore, integrin α5 might be involved in Aa Y4 invasion into gingival epithelial cells, and the resulting signal transduction cascade reduces cell adhesion by decreasing the expression of integrins, while the TLR2/4 signaling cascade regulates IL-8 expression.

Leukocyte production of inflammatory mediators is inhibited by the antioxidants phloretin, silymarin, hesperetin, and resveratrol.

PubMed

Fordham, Jezrom B; Naqvi, Afsar Raza; Nares, Salvador

2014-01-01

Antioxidants possess significant therapeutic potential for the treatment of inflammatory disorders. One such disorder is periodontitis characterised by an antimicrobial immune response, inflammation, and irreversible changes to the supporting structures of the teeth. Recognition of conserved pathogen-associated molecular patterns is a crucial component of innate immunity to Gram-negative bacteria such as Escherichia coli, as well as the periodontal pathogen Aggregatibacter actinomycetemcomitans. In this study, we investigated the antioxidants Phloretin, Silymarin, Hesperetin, and Resveratrol to ascertain whether they altered the production of inflammatory mediators by innately-activated leukocytes. Peripheral blood mononuclear cells were stimulated with lipopolysaccharide purified from Aggregatibacter actinomycetemcomitans, and the production of cytokines, chemokines, and differentiation factors was assayed by enzyme-linked immunosorbent assay, cytometric bead array, and RT-PCR. Significant inhibition of these factors was achieved upon treatment with Phloretin, Silymarin, Hesperetin, and Resveratrol. These data further characterise the potent anti-inflammatory properties of antioxidants. Their ability to inhibit the production of inflammatory cytokines, chemokines, and differentiation factors by a heterogeneous population of leukocytes has clear implications for their therapeutic potential in vivo.

Leukocyte Production of Inflammatory Mediators Is Inhibited by the Antioxidants Phloretin, Silymarin, Hesperetin, and Resveratrol

PubMed Central

Fordham, Jezrom B.; Raza Naqvi, Afsar

2014-01-01

Antioxidants possess significant therapeutic potential for the treatment of inflammatory disorders. One such disorder is periodontitis characterised by an antimicrobial immune response, inflammation, and irreversible changes to the supporting structures of the teeth. Recognition of conserved pathogen-associated molecular patterns is a crucial component of innate immunity to Gram-negative bacteria such as Escherichia coli, as well as the periodontal pathogen Aggregatibacter actinomycetemcomitans. In this study, we investigated the antioxidants Phloretin, Silymarin, Hesperetin, and Resveratrol to ascertain whether they altered the production of inflammatory mediators by innately-activated leukocytes. Peripheral blood mononuclear cells were stimulated with lipopolysaccharide purified from Aggregatibacter actinomycetemcomitans, and the production of cytokines, chemokines, and differentiation factors was assayed by enzyme-linked immunosorbent assay, cytometric bead array, and RT-PCR. Significant inhibition of these factors was achieved upon treatment with Phloretin, Silymarin, Hesperetin, and Resveratrol. These data further characterise the potent anti-inflammatory properties of antioxidants. Their ability to inhibit the production of inflammatory cytokines, chemokines, and differentiation factors by a heterogeneous population of leukocytes has clear implications for their therapeutic potential in vivo. PMID:24707119

Inhibition of P2X Receptors Protects Human Monocytes against Damage by Leukotoxin from Aggregatibacter actinomycetemcomitans and α-Hemolysin from Escherichia coli

PubMed Central

Skals, Marianne

2016-01-01

α-Hemolysin (HlyA) from Escherichia coli and leukotoxin A (LtxA) from Aggregatibacter actinomycetemcomitans are important virulence factors in ascending urinary tract infections and aggressive periodontitis, respectively. The extracellular signaling molecule ATP is released immediately after insertion of the toxins into plasma membranes and, via P2X receptors, is essential for the erythrocyte damage inflicted by these toxins. Moreover, ATP signaling is required for the ensuing recognition and phagocytosis of damaged erythrocytes by the monocytic cell line THP-1. Here, we investigate how these toxins affect THP-1 monocyte function. We demonstrate that both toxins trigger early ATP release and a following increase in the intracellular Ca2+ concentration ([Ca2+]i) in THP-1 monocytes. The HlyA- and LtxA-induced [Ca2+]i response is diminished by the P2 receptor antagonist in a pattern that fits the functional P2 receptor expression in these cells. Both toxins are capable of lysing THP-1 cells, with LtxA being more aggressive. Either desensitization or blockage of P2X1, P2X4, or P2X7 receptors markedly reduces toxin-induced cytolysis. This pattern is paralleled in freshly isolated human monocytes from healthy volunteers. Interestingly, only a minor fraction of the toxin-damaged THP-1 monocytes eventually lyse. P2X7 receptor inhibition generally prevents cell damage, except from a distinct cell shrinkage that prevails in response to the toxins. Moreover, we find that preexposure to HlyA preserves the capacity of THP-1 monocytes to phagocytose damaged erythrocytes and may induce readiness to discriminate between damaged and healthy erythrocytes. These findings suggest a new pharmacological target for protecting monocytes during exposure to pore-forming cytolysins during infection or injury. PMID:27528275

Intracranial abscess secondary to dental infection.

PubMed

Brady, Paul; Bergin, Sarah; Cryan, Bartley; Flanagan, Oisin

2014-01-01

We report a case of Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) bacteraemia and secondary brain abscess in a patient where periodontal disease was implicated as the probable source.

Buccal microbiology analyzed by infrared spectroscopy

NASA Astrophysics Data System (ADS)

de Abreu, Geraldo Magno Alves; da Silva, Gislene Rodrigues; Khouri, Sônia; Favero, Priscila Pereira; Raniero, Leandro; Martin, Airton Abrahão

2012-01-01

Rapid microbiological identification and characterization are very important in dentistry and medicine. In addition to dental diseases, pathogens are directly linked to cases of endocarditis, premature delivery, low birth weight, and loss of organ transplants. Fourier Transform Infrared Spectroscopy (FTIR) was used to analyze oral pathogens Aggregatibacter actinomycetemcomitans ATCC 29523, Aggregatibacter actinomycetemcomitans-JP2, and Aggregatibacter actinomycetemcomitans which was clinically isolated from the human blood-CI. Significant spectra differences were found among each organism allowing the identification and characterization of each bacterial species. Vibrational modes in the regions of 3500-2800 cm-1, the 1484-1420 cm-1, and 1000-750 cm-1 were used in this differentiation. The identification and classification of each strain were performed by cluster analysis achieving 100% separation of strains. This study demonstrated that FTIR can be used to decrease the identification time, compared to the traditional methods, of fastidious buccal microorganisms associated with the etiology of the manifestation of periodontitis.

Evidence for apoptosis of murine macrophages by Actinobacillus actinomycetemcomitans infection.

PubMed

Kato, S; Muro, M; Akifusa, S; Hanada, N; Semba, I; Fujii, T; Kowashi, Y; Nishihara, T

1995-10-01

The gram-negative bacterium Actinobacillus actinomycetemcomitans is considered an important etiological agent in periodontal diseases. In this study, we show that A. actinomycetemcomitans strains are cytotoxic for the murine macrophage cell line J774.1. On the other hand, Porphyromonas gingivalis strains, other gram-negative oral species implicated in adult periodontitis, showed weak cytotoxic effects. For this to occur, A. actinomycetemcomitans had to gain entry into the macrophages, since cytotoxicity was prevented by cytochalasin D. We demonstrate that cell death induced by A. actinomycetemcomitans Y4 occurs through apoptosis, as shown by changes in nuclear morphology, an increase in the proportion of fragmented DNA, and the typical ladder pattern of DNA fragmentation indicative of apoptosis. We further sought to determine whether the cytotoxicity induced by A. actinomycetemcomitans Y4 could be modulated by the protein kinase inhibitors H7 and HA1004. Apoptotic cell death induced by A. actinomycetemcomitans Y4 was suppressed by H7 but was relatively unaffected by HA1004. These findings suggest that the signals of protein kinases may regulate apoptosis induced by A. actinomycetemcomitans Y4. The ability of A. actinomycetemcomitans to promote the apoptosis of macrophages may be important for the initiation of infection and the development of periodontal diseases.

Evidence for apoptosis of murine macrophages by Actinobacillus actinomycetemcomitans infection.

PubMed Central

Kato, S; Muro, M; Akifusa, S; Hanada, N; Semba, I; Fujii, T; Kowashi, Y; Nishihara, T

1995-01-01

The gram-negative bacterium Actinobacillus actinomycetemcomitans is considered an important etiological agent in periodontal diseases. In this study, we show that A. actinomycetemcomitans strains are cytotoxic for the murine macrophage cell line J774.1. On the other hand, Porphyromonas gingivalis strains, other gram-negative oral species implicated in adult periodontitis, showed weak cytotoxic effects. For this to occur, A. actinomycetemcomitans had to gain entry into the macrophages, since cytotoxicity was prevented by cytochalasin D. We demonstrate that cell death induced by A. actinomycetemcomitans Y4 occurs through apoptosis, as shown by changes in nuclear morphology, an increase in the proportion of fragmented DNA, and the typical ladder pattern of DNA fragmentation indicative of apoptosis. We further sought to determine whether the cytotoxicity induced by A. actinomycetemcomitans Y4 could be modulated by the protein kinase inhibitors H7 and HA1004. Apoptotic cell death induced by A. actinomycetemcomitans Y4 was suppressed by H7 but was relatively unaffected by HA1004. These findings suggest that the signals of protein kinases may regulate apoptosis induced by A. actinomycetemcomitans Y4. The ability of A. actinomycetemcomitans to promote the apoptosis of macrophages may be important for the initiation of infection and the development of periodontal diseases. PMID:7558299

Aggregatibacter aphrophilus pacemaker endocarditis: a case report.

PubMed

Patel, Sahil R; Patel, Nishi H; Borah, Amit; Saltzman, Heath

2014-12-08

Aggregatibacter bacteria are a rare cause of endocarditis in adults. They are part of a group of organisms known as HACEK--Haemophilus, Aggregatibacter, Cardiobacter, Eikenella, and Kingella. Among these organisms, several Haemophilus species have been reclassified under the genus Aggregatibacter. Very few cases of Aggregatibacter endocarditis in patients with pacemaker devices have been reported. We present here what we believe to be the first case of Aggregatibacter aphrophilus pacemaker endocarditis. A 62-year-old African American male with a medical history significant for dual-chamber pacemaker placement in 1996 for complete heart block with subsequent lead manipulation in 2007, presented to his primary care doctor with fever, chills, night sweats, fatigue, and ten-pound weight loss over a four-month period. Physical examination revealed a new murmur and jugular venous distension which prompted initiation of antibiotics for suspicion of endocarditis. Both sets of initial blood cultures were positive for A. aphrophilus. Transesophageal echocardiogram revealed vegetations on the tricuspid valve and the right ventricular pacemaker lead (Figure 1). This case highlights the importance of identifying rare causes of endocarditis and recognizing that treatment may not differ from the standard treatment for typical presentations. The patient received intravenous ceftriaxone for his endocarditis for a total of six weeks. Upon device removal, temporary jugular venous pacing wires were placed. After two weeks of antibiotic treatment and no clinical deterioration, a new permanent pacemaker was placed and the patient was discharged home. This is the first case of A. aphrophilus endocarditis in a patient with a permanent pacemaker. Our patient had no obvious risk factors other than poor dentition and a history of repeated pacemaker lead manipulation. This suggests that valvulopathies secondary to repeated lead manipulation can be clinically significant factors in morbidity

RT-PCR quantification of periodontal pathogens in crack users and non-users.

PubMed

Casarin, M; Antoniazzi, R P; Vaucher, R A; Feldens, C A; Zanatta, F B

2017-04-01

To compare counts of Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis and Fusobacterium nucleatum between crack users and non-users. A cross-sectional study was conducted involving seventy-four crack cocaine users and eighty-one non-users matched for age, gender and tobacco use. Demographic and clinical variables were analysed. Subgingival bacterial samples were collected from four sites with the greatest probing depths and were analysed using real-time polymerase chain reaction. No significant difference was found in the prevalence of total counts for each bacterial species analysed between groups. However, crack users had a 1.85 (95% CI: 1.03-3.31), 2.19 (95% CI 1.24-3.88), 2.53 (95% CI 1.27-5.04) and 2.40 (95% CI 1.22-4.75) greater probability of having the higher counts (≥75th percentile) for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum, respectively. Although some crack users had higher (>75th percentile) bacterial counts for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum, total counts did not differ between crack users and non-users, leading to the hypothesis that the higher occurrence of periodontitis on crack users may be related to other non-bacterial factors. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Inhibition of Actinobacillus actinomycetemcomitans leukotoxicity by bacteria from the subgingival flora.

PubMed

Johansson, A; Hänström, L; Kalfas, S

2000-08-01

Actinobacillus actinomycetemcomitans produces a pore-forming leukotoxin that lyses human polymorphonuclear leukocytes and monocytes. Certain proteolytic bacteria may coexist with A. actinomycetemcomitans in periodontal pockets. We aimed therefore to examine whether oral bacteria can modify the leukotoxicity of A. actinomycetemcomitans. A total of 55 strains representing 45 bacterial species of the subgingival flora were tested. Each strain was incubated with the highly toxic strain of A. actinomycetemcomitans HK 1519 and the leukotoxic activity of the suspension against human polymorphonuclear leukocytes was determined from the activity of the lactate dehydrogenase released upon lysis of the leukocytes. Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Prevotella melaninogenica and Prevotella loeschii inhibited the leukotoxicity of A. actinomycetemcomitans cells as well as the activity of leukotoxin purified from the same strain. The bacterial strains without the ability to block leukotoxic activity also failed to destroy pure leukotoxin even after 5 h of incubation. The proteolytic degradation of leukotoxin by P. gingivalis was mainly dependent on the activity of the enzymes R- and K-gingipains. P. intermedia and P. nigrescens also degraded the leukotoxin by enzymes. The results imply a role of the periodontal microflora in modifying the virulence of A. actinomycetemcomitans by destroying its leukotoxin.

Intra-oral colonization of macaque monkeys by Actinobacillus actinomycetemcomitans

PubMed Central

Beighton, David; Taichman, Norton S.; Simpson, David L.; Dirienzo, Joseph M.; Johnson, Newell W.

2012-01-01

Actinobacillus actinomycetemcomitans was acquired by captive Macaca fascicularis 3 to 6 months after birth, and all monkeys aged over 6 months harbored detectable levels. This microorganism was most frequently isolated from the gingival plaque of the incisor (and other) teeth compared with other oral sites. Strains were leukotoxic by bioassay and Western blot analysis. Antibodies in macaque serum contained neutralized the leukotoxin of a human A. actinomycetemcomitans strain. High titres of maternal neutralizing anti-leukotoxin antibodies were detected in neonates; the titre then fell rapidly so that by 6 months the antibody titer was zero. Antileukotoxin antibody production was detected after 6 months of age, rapidly reaching a high level within 2 years after birth. The presence of leukotoxic strains of A. actinomycetemcomitans in the gingival region did not appear to be correlated with an increase in susceptibility to periodontal disease. PMID:2628866

Opsonic antibody activity against Actinobacillus actinomycetemcomitans in patients with rapidly progressive periodontitis.

PubMed Central

Sjöström, K; Darveau, R; Page, R; Whitney, C; Engel, D

1992-01-01

Actinobacillus actinomycetemcomitans has been closely associated with early-onset, severe periodontitis, and such patients often have serum immunoglobulin G (IgG) antibodies reactive with antigens of this gram-negative pathogen. We examined the functionality and potential importance of these antibodies. The opsonic activity against A. actinomycetemcomitans of sera from 30 patients with rapidly progressive periodontitis (RPP) and from 28 periodontally normal subjects was tested by using polymorphonuclear leukocyte (PMN) chemiluminescence and bactericidal assays. Peak chemiluminescence values correlated strongly with killing observed in the PMN-dependent bactericidal assay (r = 0.88; P < 0.001). Neither the mean IgG titer nor the mean peak chemiluminescence differed significantly between the two groups. However, when the relationship between chemiluminescence and titer was examined, regression analysis showed that antibodies present in low-titer normal sera were significantly more effective at opsonizing A. actinomycetemcomitans than antibodies present in low-titer RPP patient sera (P = 0.04). Thus, periodontally normal individuals may be better able than RPP patients to clear A. actinomycetemcomitans in early stages of colonization, and anti-A. actinomycetemcomitans antibodies in RPP patients may be relatively ineffective in preventing infection by this organism. PMID:1398993

Actinobacillus actinomycetemcomitans in Human Periodontal Disease: a Cross-Sectional Microbiological Investigation

PubMed Central

Slots, Jørgen; Reynolds, Homer S.; Genco, Robert J.

1980-01-01

Actinobacillus actinomycetemcomitans is a facultative gram-negative bacterium which has been associated with severe oral and nonoral infections. This study examined its occurrence in the oral cavities of 10 normal juveniles, 11 normal adults, 10 juvenile periodontitis patients, and 12 adult periodontitis patients. Four deep periodontal pockets and two normal periodontal sites were sampled in the diseased patients, and six normal periodontal sites were sampled in the healthy individuals. In all subjects samples were obtained from the cheek, tongue, and saliva. Samples from a total of 172 normal periodontal sites, 83 deep periodontal pockets, 42 cheek mucosae, 42 tongue dorsa, and 42 salivas were examined. Isolation was performed by using a medium for selective isolation of A. actinomycetemcomitans (Trypticase soy agar [BBL Microbiology Systems] supplemented with 10% serum and 75 μg of bacitracin per ml). The carrier rates were 20% for normal juveniles, 36% for normal adults, 50% for adult periodontitis patients, and 90% for juvenile periodontitis patients. A. actinomycetemcomitans was on average recovered in about fivefold-higher numbers from infected deep periodontal pockets than from infected normal subgingival areas. Samples of periodontal pockets generally contained 100-fold-more cells of A. actinomycetemcomitans than did samples of the cheek, tongue, and saliva. A. actinomycetemcomitans is commonly isolated from patients with juvenile periodontitis, often isolated from patients with adult periodontitis, and occasionally isolated from normal juveniles and adults. Its primary oral ecological niche appears to be dental plaque and periodontal pockets. PMID:6968718

In vivo induced antigenic determinants of Actinobacillus actinomycetemcomitans.

PubMed

Cao, Sam Linsen; Progulske-Fox, Ann; Hillman, Jeffrey D; Handfield, Martin

2004-08-01

Actinobacillus actinomycetemcomitans is a Gram-negative capnophilic rod and the etiological agent of localized aggressive periodontitis. The genome-wide survey of A. actinomycetemcomitans using in vivo induced antigen technology (IVIAT) has previously resulted in the discovery of antigenic determinants expressed specifically in diseased patients. The present study evaluated the potential of these antigens as putative disease markers, and investigating their contribution to the pathogenesis of the microorganism. Sera from patients had a significantly greater antibody titer than sera from healthy controls against six antigens, which supports the in vivo expression of these antigens, and suggests their usefulness as disease markers. A. actinomycetemcomitans invasion of epithelium-derived HeLa cells resulted in the induction of all three genes tested, as evidenced by real-time PCR. Isogenic mutants of these three genes were constructed and the adhesion and intracellular survival of the mutants was assayed in a competition assay with the wild-type strain. A significant defect in the intracellular survival of two of these mutant strains (orf1402 and orf859) was found. This defect could not be attributed to an adhesion defect. In contrast, a mutation in vapA, a homologue of a novel putative transcriptional regulator, out-competed the wild-type strain in the same assay. The virulent phenotype was restored for a mutant strain in orf859 upon complementation. This data provided new insight into the pathogenic personality of A. actinomycetemcomitans in vivo and supported the use of HeLa cells as a valid in vitro host-pathogen interactions model for that microorganism. IVIAT is applicable to most pathogens and will undoubtedly lead to the discovery of novel therapies, antibiotics and diagnostic tools.

Effect of treatment on titer, function, and antigen recognition of serum antibodies to Actinobacillus actinomycetemcomitans in patients with rapidly progressive periodontitis.

PubMed Central

Sjöström, K; Ou, J; Whitney, C; Johnson, B; Darveau, R; Engel, D; Page, R C

1994-01-01

Although periodontal treatment by scaling and root planing (SCRP) is known to induce bacteremia, the effect of this procedure on the host immune response is not known. We have determined pre- and post-SCRP immunoglobulin G antibody titers to antigens of Actinobacillus actinomycetemcomitans in the sera of 22 patients with rapidly progressive periodontitis. We also assessed the ability of these sera to enhance phagocytosis and killing of A. actinomycetemcomitans by human polymorphonuclear leukocytes by using a polymorphonuclear leukocyte chemiluminescence (CL) assay. Specific anti-A. actinomycetemcomitans antibody titers were significantly increased at 6 and 12 months after beginning treatment, and CL values were significantly increased at 12 months, whereas mean interproximal pocket depths were significantly decreased at 12 months after beginning treatment. When patients were classified as either seropositive (twice the median titer of control subjects; n = 10) or seronegative (n = 12), both median titers and CL values were significantly increased for the seronegative group at 6 and 12 months after treatment. In the seropositive group, only the median titer was significantly increased at 12 months. Western blot (immunoblot) patterns for six seronegative and six seropositive patients differed remarkably at the baseline. Before treatment, all of the seropositive patients recognized high-molecular-mass lipopolysaccharide (LPS) and a large number of protein components. Patterns were virtually unaffected by therapy. Before treatment, only one of the seronegative patients recognized the LPS smear and none reacted strongly with protein components. Following treatment, slight LPS staining was observed for five of six seronegative patients and detection of protein bands was enhanced in all cases. We conclude that treatment by SCRP induces a humoral immune response, especially in seronegative patients, and that response may play a role in the observed beneficial effects of

Nonspecific Adherence by Actinobacillus actinomycetemcomitans Requires Genes Widespread in Bacteria and Archaea

PubMed Central

Kachlany, Scott C.; Planet, Paul J.; Bhattacharjee, Mrinal K.; Kollia, Evyenia; DeSalle, Rob; Fine, Daniel H.; Figurski, David H.

2000-01-01

The gram-negative coccobacillus, Actinobacillus actinomycetemcomitans, is the putative agent for localized juvenile periodontitis, a particularly destructive form of periodontal disease in adolescents. This bacterium has also been isolated from a variety of other infections, notably endocarditis. Fresh clinical isolates of A. actinomycetemcomitans form tenacious biofilms, a property likely to be critical for colonization of teeth and other surfaces. Here we report the identification of a locus of seven genes required for nonspecific adherence of A. actinomycetemcomitans to surfaces. The recently developed transposon IS903φkan was used to isolate mutants of the rough clinical isolate CU1000 that are defective in tight adherence to surfaces (Tad−). Unlike wild-type cells, Tad− mutant cells adhere poorly to surfaces, fail to form large autoaggregates, and lack long, bundled fibrils. Nucleotide sequencing and genetic complementation analysis revealed a 6.7-kb region of the genome with seven adjacent genes (tadABCDEFG) required for tight adherence. The predicted TadA polypeptide is similar to VirB11, an ATPase involved in macromolecular transport. The predicted amino acid sequences of the other Tad polypeptides indicate membrane localization but no obvious functions. We suggest that the tad genes are involved in secretion of factors required for tight adherence of A. actinomycetemcomitans. Remarkably, complete and highly conserved tad gene clusters are present in the genomes of the bubonic plague bacillus Yersinia pestis and the human and animal pathogen Pasteurella multocida. Partial tad loci also occur in strikingly diverse Bacteria and Archaea. Our results show that the tad genes are required for tight adherence of A. actinomycetemcomitans to surfaces and are therefore likely to be essential for colonization and pathogenesis. The occurrence of similar genes in a wide array of microorganisms indicates that they have important functions. We propose that tad

Association between periodontal condition and subgingival microbiota in women during pregnancy: a longitudinal study.

PubMed

Borgo, Priscila Viola; Rodrigues, Viviane Aparecida Arenas; Feitosa, Alfredo Carlos Rodrigues; Xavier, Karla Correa Barcelos; Avila-Campos, Mario Julio

2014-01-01

In this study, the gingival conditions and the quantitative detection for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in pregnant women were determined. Quantitative determinations of periodontal bacteria by using a SyBr green system in women during pregnancy were performed. Women at the 2nd and 3rd trimesters of pregnancy and non-pregnant women were included in this study. A. actinomycetemcomitans was observed in high numbers in women at the 2nd and 3rd trimesters of pregnancy with a significant difference (p<0.05). F. nucleatum and P. intermedia were also observed in high levels. Our results show that pregnant women are more susceptible to gingivitis, and the presence of A. actinomycetemcomitans in subgingival biofilm might be taken into account for the treatment of periodontal disease.

[Non-specific immunosuppressive effect induced by A. actinomycetemcomitans].

PubMed

Ochiai, K; Kurita, T; Kamino, Y; Ikeda, T

1990-09-01

Previous studies have shown that immunosuppressive effects are related to the pathogenicity of periodontopathic bacteria and the development of periodontal disease. We reported soluble sonic extracts (SE) from A. actinomycetemcomitans and B. intermedius had a strong immunosuppressive effect on primary response of anti-SRBC plaque forming cells. SE from A. actinomycetemcomitans inhibited the IgM----IgG isotype switching. The purpose of this study was to investigate the effect of SE on secondary immunoresponse. As a control, mice (C3H/HeN) were immunized with intraperitoneal injection of SRBC and complete Freund's adjuvant, and additional SRBC after 30 days. In order to study the effect of SE from A. actinomycetemcomitans on secondary response, four groups were prepared in this study. One group of C3H/HeN mice were injected SE intravenously before the primary immunization of SRBC. The other three groups were given SE at different time on secondary injection of SRBC and designated the pre-, post-, or simultaneous injection, respectively. Hemolytic plaque assay was performed and estimated anti-SRBC plaque forming cells in each immunoglobulin class and IgG subclass, on the 5th day after the secondary injection. The immunosuppressive effect was found in all the groups which we examined. The present study strongly suggests that periodontopathic bacteria have strong adjuvant activity, and long-term Actinobacillus infection accompanied by periodontal fluctuation in bacterial flora may induce aberration in the immune system. The suppressed immune system explain the explosive growth of bacteria tested in our investigation, resulting in the mixed or opportunistic infection by bacteria harbored in the gingival crevice.

Defining Genetic Fitness Determinants and Creating Genomic Resources for an Oral Pathogen

PubMed Central

Narayanan, Ajay M.; Ramsey, Matthew M.

2017-01-01

ABSTRACT Periodontitis is a microbial infection that destroys the structures that support the teeth. Although it is typically a chronic condition, rapidly progressing, aggressive forms are associated with the oral pathogen Aggregatibacter actinomycetemcomitans. One of this bacterium's key virulence traits is its ability to attach to surfaces and form robust biofilms that resist killing by the host and antibiotics. Though much has been learned about A. actinomycetemcomitans since its initial discovery, we lack insight into a fundamental aspect of its basic biology, as we do not know the full set of genes that it requires for viability (the essential genome). Furthermore, research on A. actinomycetemcomitans is hampered by the field's lack of a mutant collection. To address these gaps, we used rapid transposon mutant sequencing (Tn-seq) to define the essential genomes of two strains of A. actinomycetemcomitans, revealing a core set of 319 genes. We then generated an arrayed mutant library comprising >1,500 unique insertions and used a sequencing-based approach to define each mutant's position (well and plate) in the library. To demonstrate its utility, we screened the library for mutants with weakened resistance to subinhibitory erythromycin, revealing the multidrug efflux pump AcrAB as a critical resistance factor. During the screen, we discovered that erythromycin induces A. actinomycetemcomitans to form biofilms. We therefore devised a novel Tn-seq-based screen to identify specific factors that mediate this phenotype and in follow-up experiments confirmed 4 mutants. Together, these studies present new insights and resources for investigating the basic biology and disease mechanisms of a human pathogen. IMPORTANCE Millions suffer from gum disease, which often is caused by Aggregatibacter actinomycetemcomitans, a bacterium that forms antibiotic-resistant biofilms. To fully understand any organism, we should be able to answer: what genes does it require for life

Association between periodontal condition and subgingival microbiota in women during pregnancy: a longitudinal study

PubMed Central

BORGO, Priscila Viola; RODRIGUES, Viviane Aparecida Arenas; FEITOSA, Alfredo Carlos Rodrigues; XAVIER, Karla Correa Barcelos; AVILA-CAMPOS, Mario Julio

2014-01-01

Objectivo In this study, the gingival conditions and the quantitative detection for Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia in pregnant women were determined. Material and Methods Quantitative determinations of periodontal bacteria by using a SyBr green system in women during pregnancy were performed. Women at the 2nd and 3rd trimesters of pregnancy and non-pregnant women were included in this study. A. actinomycetemcomitans was observed in high numbers in women at the 2nd and 3rd trimesters of pregnancy with a significant difference (p<0.05). F. nucleatum and P. intermedia were also observed in high levels. Results and Conclusion Our results show that pregnant women are more susceptible to gingivitis, and the presence of A. actinomycetemcomitans in subgingival biofilm might be taken into account for the treatment of periodontal disease. PMID:25591021

Cerebral hemorrhage in infective endocarditis caused by Actinobacillus actinomycetemcomitans.

PubMed

Lin, Gen-Min; Chu, Kai-Min; Juan, Chun-Jung; Chang, Feng-Yee

2007-11-01

Cerebral hemorrhage occurs rarely in endocarditis caused by Actinobacillus actinomycetemcomitans. A 51-year-old man with a prosthetic mitral valve, who had been prophylactically treated (7 years) with warfarin, presented with intermittent fever. On admission, a Levine grade II/VI systolic cardiac murmur was detected. A transthoracic echocardiogram was negative for valve vegetation. Cefepime (1 g every 8 hours) was administered intravenously. On day 4, culturing of Gram-negative bacilli from blood and a transesophageal echocardiogram revealed a small oscillating filament attached to lateral mitral prosthetic ring on the atrial side. Ceftriaxone (2 g once daily) was started. Gait instability and left-side weakness developed abruptly 2 weeks later; brain magnetic resonance imaging revealed a hematoma over the right parietal-occipital lobe. Ceftriaxone was adjusted to 2 g every 12 hours. Actinobacillus actinomycetemcomitans was identified 3 weeks later. Recovery was achieved, with significant interval improvement and resolution of the cerebral lesions evident on CT.

Antibacterial activity of the lactoperoxidase system combined with edible Laminaria hot-water extract as a source of halide ions.

PubMed

Shin, Kouichirou; Nakano, Manabu; Yamauchi, Koji; Toida, Tomohiro; Iwatsuki, Keiji

2012-01-01

Hot-water extracts prepared from nine out of 12 samples of dried edible Laminaria reduced the viable numbers of Aggregatibacter actinomycetemcomitans, Staphylococcus aureus, and Esherichia coli below the detection limit after incubation for 5 min when combined with lactoperoxidase, glucose oxidase, and glucose. Some extracts showed higher bactericidal activity and a higher OI(-) concentration in the assay mixture after ultrafiltration.

Cervical spondylodiscitis with spinal epidural abscess caused by Aggregatibacter aphrophilus.

PubMed

Pasqualini, Leonella; Mencacci, Antonella; Scarponi, Anna Maria; Leli, Christian; Fabbriciani, Gianluigi; Callarelli, Laura; Schillaci, Giuseppe; Bistoni, Francesco; Mannarino, Elmo

2008-05-01

Spondylodiscitis caused by Aggregatibacter aphrophilus, formerly known as Haemophilus paraphrophilus, is an unusual condition and can be very difficult to diagnose. We report a case of cervical spondylodiscitis complicated by spinal epidural abscess in a 63-year-old woman, without underlying predisposing conditions. The source of infection was identified as a periodontal infection. The patient was successfully treated with systemic antibiotics.

Gram-negative periodontal bacteria induce the activation of Toll-like receptors 2 and 4, and cytokine production in human periodontal ligament cells.

PubMed

Sun, Ying; Shu, Rong; Li, Chao-Lun; Zhang, Ming-Zhu

2010-10-01

Periodontitis is a bacterially induced chronic inflammatory disease. Toll-like receptors (TLRs), which could recognize microbial pathogens, are important components in the innate and adaptive immune systems. Both qualitatively and quantitatively distinct immune responses might result from different bacteria stimulation and the triggering of different TLRs. This study explores the interaction of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) with TLR2 and TLR4. We studied the gene expression changes of TLR2 and TLR4 and cytokine production (interleukin-1β, -6, -8, -10, and tumor necrosis factor-alpha) in human periodontal ligament cells (HPDLCs) stimulated with heat-killed bacteria or P. gingivalis lipopolysaccharide (LPS) in the presence or absence of monoclonal antibodies to TLR2 or TLR4 (anti-TLR2/4 mAb). Both test bacteria and 10 microg/ml P. gingivalis LPS treatment increased the gene expression of TLR2 and TLR4 and cytokine production in HPDLCs. In addition, these upregulations could be blocked by anti-TLR2/4 mAb. However, the expression of TLR4 mRNA in HPDLCs stimulated with 1 microg/ml P. gingivalis LPS was not increased. No differences were found in the cytokine production caused by 1 microg/ml P. gingivalis LPS treatment in the presence or absence of anti-TLR4 mAb. These patterns of gene expression and cytokine production indicate that Gram-negative periodontal bacteria or their LPS might play a role in triggering TLR2 and/or TLR4, and be of importance for the immune responses in periodontitis.

Complete Genome Sequence of Aggregatibacter (Haemophilus) aphrophilus NJ8700▿

PubMed Central

Di Bonaventura, Maria Pia; DeSalle, Rob; Pop, Mihai; Nagarajan, Niranjan; Figurski, David H.; Fine, Daniel H.; Kaplan, Jeffrey B.; Planet, Paul J.

2009-01-01

We report the finished and annotated genome sequence of Aggregatibacter aphrophilus strain NJ8700, a strain isolated from the oral flora of a healthy individual, and discuss characteristics that may affect its dual roles in human health and disease. This strain has a rough appearance, and its genome contains genes encoding a type VI secretion system and several factors that may participate in host colonization. PMID:19447908

Detection and quantification of periodontal pathogens in smokers and never-smokers with chronic periodontitis by real-time polymerase chain reaction.

PubMed

Guglielmetti, Mariana R; Rosa, Ecinele F; Lourenção, Daniele S; Inoue, Gislene; Gomes, Elaine F; De Micheli, Giorgio; Mendes, Fausto Medeiros; Hirata, Rosário D C; Hirata, Mario H; Pannuti, Claudio M

2014-10-01

The purpose of the present investigation is to compare the presence and number of periodontal pathogens in the subgingival microbiota of smokers versus never-smokers with chronic periodontitis and matched probing depths (PDs) using real-time polymerase chain reaction (RT-PCR). Forty current smokers and 40 never-smokers, matched for age, sex, and mean PD of sampling site, were included in this investigation. A full-mouth periodontal examination was performed, and a pooled subgingival plaque sample was collected from the deepest site in each quadrant of each participant. To confirm smoking status, expired carbon monoxide (CO) concentrations were measured with a CO monitor. The presence and quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were determined using RT-PCR. Smokers had greater overall mean PD (P = 0.001) and attachment loss (P = 0.006) and fewer bleeding on probing sites (P = 0.001). An association was observed between smoking status and the presence of A. actinomycetemcomitans (P <0.001). The counts of A. actinomycetemcomitans (P <0.001), P. gingivalis (P = 0.042), and T. forsythia (P <0.001) were significantly higher in smokers. Smokers showed significantly greater amounts of P. gingivalis, A. actinomycetemcomitans, and T. forsythia than never-smokers. There was a significant association between smoking and the presence of A. actinomycetemcomitans.

Antimicrobial effects of citrus sinensis peel extracts against periodontopathic bacteria: an in vitro study.

PubMed

Hussain, Khaja Amjad; Tarakji, Bassel; Kandy, Binu Purushothaman Panar; John, Jacob; Mathews, Jacob; Ramphul, Vandana; Divakar, Darshan Devang

2015-01-01

Use of plant extracts and phytochemicals with known antimicrobial properties may have great significance in therapeutic treatments. To assess the in vitro antimicrobial potential and also determine the minimum inhibitory concentration (MIC) of Citrus sinensis peel extracts with a view of searching a novel extract as a remedy for periodontal pathogens. Aqueous and ethanol (cold and hot) extracts prepared from peel of Citrus sinensis were screened for in vitro antimicrobial activity against Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, using agar well diffusion method. The lowest concentration of every extract considered as the minimal inhibitory concentration (MIC) values were determined for both test organisms. Confidence level and level of significance were set at 95% and 5% respectively. Prevotella intermedia and Porphyromonas gingivalis were resistant to aqueous extracts while Aggregatibacter actinomycetemcomitans was inhibited at very high cncentrations. Hot ethanolic extracts showed significantly higher zone of inhibition than cold ethanolic extract. Minimum inhibitory concentration of hot and cold ethanolic extracts of Citrus sinensis peel ranged between 12-15 mg/ml against all three periodontal pathogens. Both extracts were found sensitive and contain compounds with therapeutic potential. Nevertheless, clinical trials on the effect of these plants are essential before advocating large-scale therapy.

Racial tropism of a highly toxic clone of Actinobacillus actinomycetemcomitans associated with juvenile periodontitis.

PubMed Central

Haubek, D; Dirienzo, J M; Tinoco, E M; Westergaard, J; López, N J; Chung, C P; Poulsen, K; Kilian, M

1997-01-01

Actinobacillus actinomycetemcomitans strains with enhanced levels of production of leukotoxin are characterized by a 530-bp deletion from the promoter region of the leukotoxin gene operon. Previous isolates with this deletion constituted a single clone belonging to serotype b, although they displayed minor differences among each other. We have analyzed the geographic dissemination of this clone by examining 326 A. actinomycetemcomitans isolates from healthy and periodontally diseased individuals as well as from patients with different types of extraoral infections originating from countries worldwide. A total of 38 isolates, all belonging to the same clone, showed the 530-bp deletion. Comparison of a 440-bp sequence from the promoter region of the leukotoxin gene operon from 10 of these strains revealed complete identity, which indicates that the deletion originates from a single mutational event. This particular clone was exclusively associated with localized juvenile periodontitis (LJP). In at least 12 of 28 families from which the clone was isolated, more than one family member had LJP. Notably, all the subjects carrying this clone had a genetic affiliation with the African population. These observations suggest that juvenile periodontitis in some adolescents with an African origin is associated with a disseminating clone of A. actinomycetemcomitans. PMID:9399490

Effects of ozone nano-bubble water on periodontopathic bacteria and oral cells - in vitro studies

NASA Astrophysics Data System (ADS)

Hayakumo, Sae; Arakawa, Shinichi; Takahashi, Masayoshi; Kondo, Keiko; Mano, Yoshihiro; Izumi, Yuichi

2014-10-01

The aims of the present study were to evaluate the bactericidal activity of a new antiseptic agent, ozone nano-bubble water (NBW3), against periodontopathogenic bacteria and to assess the cytotoxicity of NBW3 against human oral cells. The bactericidal activities of NBW3 against representative periodontopathogenic bacteria, Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) were evaluated using in vitro time-kill assays. The cytotoxicity of NBW3 was evaluated using three-dimensional human buccal and gingival tissue models. The numbers of colony forming units (CFUs)/mL of P. gingivalis and A. actinomycetemcomitans exposed to NBW3 dropped to below the lower limit of detection (<10 CFUs mL-1) after only 0.5 min of exposure. There were only minor decreases in the viability of oral tissue cells after 24 h of exposure to NBW3. These results suggest that NBW3 possesses potent bactericidal activity against representative periodontopathogenic bacteria and is not cytotoxic to cells of human oral tissues. The use of NBW3 as an adjunct to periodontal therapy would be promising.

Essential Oils from Ugandan Aromatic Medicinal Plants: Chemical Composition and Growth Inhibitory Effects on Oral Pathogens

PubMed Central

Ocheng, Francis; Bwanga, Freddie; Joloba, Moses; Softrata, Abier; Azeem, Muhammad; Pütsep, Katrin; Borg-Karlson, Anna-Karin; Obua, Celestino; Gustafsson, Anders

2015-01-01

The study assessed the growth inhibitory effects of essential oils extracted from ten Ugandan medicinal plants (Bidens pilosa, Helichrysum odoratissimum, Vernonia amygdalina, Hoslundia opposita, Ocimum gratissimum, Cymbopogon citratus, Cymbopogon nardus, Teclea nobilis, Zanthoxylum chalybeum, and Lantana trifolia) used traditionally in the management of oral diseases against oral pathogens. Chemical compositions of the oils were explored by GC-MS. Inhibitory effects of the oils were assessed on periodontopathic Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans and cariogenic Streptococcus mutans and Lactobacillus acidophilus using broth dilution methods at concentrations of 1%, 0.1%, and 0.01%. The most sensitive organism was A. actinomycetemcomitans. Its growth was markedly inhibited by six of the oils at all the concentrations tested. Essential oil from C. nardus exhibited the highest activity with complete growth inhibition of A. actinomycetemcomitans and P. gingivalis at all the three concentrations tested, the major constituents in the oil being mainly oxygenated sesquiterpenes. Most of the oils exhibited limited effects on L. acidophilus. We conclude that essential oils from the studied plants show marked growth inhibitory effects on periodontopathic A. actinomycetemcomitans and P. gingivalis, moderate effects on cariogenic S. mutans, and the least effect on L. acidophilus. The present study constitutes a basis for further investigations and development of certain oils into alternative antiplaque agents. PMID:26170872

Impact of CDT Toxin on Human Diseases.

PubMed

Faïs, Tiphanie; Delmas, Julien; Serres, Arnaud; Bonnet, Richard; Dalmasso, Guillaume

2016-07-15

Cytolethal distending toxin (CDT) is found in Gram-negative bacteria, especially in certain Proteobacteria such as the Pasteurellaceae family, including Haemophilus ducreyi and Aggregatibacter (Actinobacillus) actinomycetemcomitans, in the Enterobacteriaceae family and the Campylobacterales order, including the Campylobacter and Helicobacter species. In vitro and in vivo studies have clearly shown that this toxin has a strong effect on cellular physiology (inflammation, immune response modulation, tissue damage). Some works even suggest a potential involvement of CDT in cancers. In this review, we will discuss these different aspects.

Changes in oral microflora after full-mouth tooth extraction: a prospective cohort study.

PubMed

de Waal, Yvonne C M; Winkel, Edwin G; Raangs, Gerwin C; van der Vusse, Marleen L; Rossen, John W A; van Winkelhoff, Arie Jan

2014-10-01

The aim of the study was to evaluate the effect of full-mouth tooth extraction on the oral microflora, with emphasis on the presence and load of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Adult patients (n = 30), with moderate to advanced periodontitis and scheduled for full-mouth tooth extraction, were consecutively selected. Prior to and 1 and 3 months after full-mouth tooth extraction saliva, tongue, buccal and gingival mucosa and subgingival plaque/prosthesis samples were obtained. Aerobic and anaerobic culture techniques and quantitative real-time polymerase chain reaction (qPCR) were employed for the detection of oral pathogens. Full-mouth tooth extraction resulted in reduction below detection level of A. actinomycetemcomitans and P. gingivalis in 15 of 16 and 8 of 16 previously positive patients using culture techniques and qPCR, respectively. Those patients remaining qPCR positive showed a significant reduction in load of these bacteria. Full-mouth tooth extraction significantly changes the oral microflora. These changes include reduction of A. actinomycetemcomitans and P. gingivalis, frequently to levels below detection threshold. In some patients, A. actinomycetemcomitans and P. gingivalis can persist in the edentulous oral cavity up to 3 months after full-mouth tooth extraction. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Detection of selected periodontal bacteria in preschool children affected by early childhood caries.

PubMed

Pantuckova, Pavla; Bartosova, Michaela; Broukal, Zdenek; Kukletova, Martina; Holla, Lydie Izakovicova

2016-11-01

The aim of this study was to compare the detection frequency of periodontal bacteria in dental plaque in children with early childhood caries (ECC) with and without gingival inflammation. A convenience sample of 25 preschool children (mean age 3.61 years, SD 1.42) was recruited. Dental plaque was taken from periodontal areas with and without visible signs of inflammation and processed using the StomaGene® (Protean s.r.o. Czech Republic) and ParoCheck® 20 (Greiner Bio-one GmbH, Germany) detection kits. The two sample t tests between percents for differences between inflammatory and healthy sites and kappa statistics for the agreement of both systems were used. At the inflammatory sites, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were significantly more frequently detected by StomaGene® while Fusobacterium nucleatum, A. actinomycetemcomitans, Tanarella forsythia and Prevotella intermedia were significantly more frequently identified by ParoCheck® test. The agreement between the two detection systems was substantial for A. actinomycetemcomitans and F. nucleatum in the samples collected from inflamed sites and only for F. nucleatum from clinically healthy sites. Therefore, we recommend that the same system should be used when the same patient is examined repeatedly.

Bactericidal effects of a high-power, red light-emitting diode on two periodontopathic bacteria in antimicrobial photodynamic therapy in vitro.

PubMed

Umeda, Makoto; Tsuno, Akiko; Okagami, Yoshihide; Tsuchiya, Fumito; Izumi, Yuichi; Ishikawa, Isao

2011-11-01

  Light-emitting diodes have been investigated as new light activators for photodynamic therapy. We investigated the bactericidal effects of high-power, red light-emitting diodes on two periodontopathic bacteria in vitro.   A light-emitting diode (intensity: 1100 mW/cm(2) , peak wavelength: 650 nm) was used to irradiate a bacterial solution for either 10 or 20 s. Bacterial solutions (Porphyromonas gingivalis or Aggregatibacter actinomycetemcomitans) at a concentration of 2.5 × 10(6) c.f.u./mL were mixed with an equal volume of either methylene blue or toluidine blue O (0-20 μg/mL) and added to titer plate wells. The plate wells were irradiated with red light-emitting diode light from a distance of 22 or 40 mm. The contents were diluted, and 50 μL was smeared onto blood agar plates. After 1 week of culturing, bacterial c.f.u. were counted.   The light-emitting diode energy density was estimated to be approximately 4 and 8 J/cm(2) after 10 and 20 s of irradiation, respectively. Red light-emitting diode irradiation for 10 s from a distance of 22 mm, combined with methylene blue at concentrations >10 μg/mL, completely killed Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans.   High-power, red light-emitting diode irradiation with a low concentration of dye showed effective bactericidal effects against two periodontopathic bacteria. © 2011 Blackwell Publishing Asia Pty Ltd.

Crystallization and preliminary X-ray crystallographic analysis of MacA from Actinobacillus actinomycetemcomitans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piao, Shunfu; Xu, Yongbin; Ha, Nam-Chul, E-mail: hnc@pusan.ac.kr

2008-05-01

A periplasmic membrane-fusion protein MacA from Actinobacillus actinomycetemcomitans, an essential component of the multidrug efflux pump in Gram-negative bacteria, was crystallized. Periplasmic membrane-fusion proteins (MFPs) are an essential component of the multidrug efflux pump in Gram-negative bacteria. They play a crucial role in bridging the outer membrane porin TolC and two distinct types of inner membrane transporters. The MFP MacA bridges the inner membrane ABC-type multidrug transporter MacB and the outer membrane porin TolC. MacA from the pathogenic bacterium Actinobacillus actinomycetemcomitans was expressed in Escherichia coli B834 (DE3) and the recombinant protein was purified using Ni–NTA affinity, Q anion-exchange andmore » gel-filtration chromatography. The purified MacA protein was crystallized using the vapour-diffusion method. A MAD diffraction data set was collected to a resolution of 3.0 Å at 100 K. The crystal belongs to space group P622, with unit-cell parameters a = b = 109.2, c = 255.4 Å, α = β = 90, γ = 120°, and contains one molecule in the asymmetric unit.« less

Antimicrobial effect of platelet-rich plasma and platelet-rich fibrin.

PubMed

Badade, Pallavi S; Mahale, Swapna A; Panjwani, Alisha A; Vaidya, Prutha D; Warang, Ayushya D

2016-01-01

Platelet concentrates have been extensively used in a variety of medical fields to promote soft- and hard-tissue regeneration. The significance behind their use lies in the abundance of growth factors (GFs) in platelets α-granules that promote wound healing. Other than releasing a pool of GFs upon activation, platelets also have many features that indicate their role in the anti-infective host defense. The aim of this study is to evaluate the antimicrobial activities of platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) against periodontal disease-associated bacteria. Blood samples were obtained from ten adult male patients. PRP and PRF were procured using centrifugation. The antimicrobial activity of PRP and PRF was evaluated by microbial culturing using bacterial strains of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. P. gingivalis and A. actinomycetemcomitans were inhibited by PRP but not by PRF. PRP is a potentially useful substance in the fight against periodontal pathogens. This might represent a valuable property in adjunct to the enhancement of tissue regeneration.

Periodontal microbiology in Latin America.

PubMed

Contreras, Adolfo; Moreno, Sandra M; Jaramillo, Adriana; Pelaez, Melissa; Duque, Andres; Botero, Javier E; Slots, Jørgen

2015-02-01

This review article describes the microbiota associated with periodontal disease in Latin America. This vast territory includes 22 nations, which show great ethnic diversity, with large groups of White people, Black people, Mestizo people and Native people. Widespread poverty and limited access to education and health-care services, including periodontal care, are prominent predisposing factors for destructive periodontal disease in Latin America. Black people and Mestizo people seem to have particularly severe periodontal disease and are frequently colonized by the major periodontal pathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. The 'red complex' bacterial pathogens and A. actinomycetemcomitans predominate in chronic and aggressive periodontitis, but gram-negative enteric rods and herpesviruses can also play important periodontopathic roles in Latin America. The key to minimizing the risk of periodontal disease is control of the pathogens, and new low-cost periodontal treatments deserve serious consideration in Latin America. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In vitro antibacterial activity of ethanolic extract of Morus alba leaf against periodontal pathogens.

PubMed

Gunjal, Shilpa; Ankola, Anil V; Bhat, Kishore

2015-01-01

Antibiotic resistance is a major problem with inadvertent usage. Thus, there is a need to search for new antimicrobial agents of herbal origin to combat antibiotic resistance. One such plant is Morus alba which has a long history of medicinal use in traditional Chinese medicine. To compare the antibacterial activity of ethanolic extract of M. alba leaves with chlorhexidine gluconate against Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia. Experimental in vitro study. Crude extract from the leaves of M. alba were prepared by Soxhlet extraction method by using ethanol as a solvent. Minimum inhibitory concentration (MIC) of the extract was assessed against A. actinomycetemcomitans, P. gingivalis and T. forsythia, and compared with that of chlorhexidine gluconate by broth dilution method. P. gingivalis was the most sensitive organism against the M. alba extract with an MIC value of 1.95 mg/ml; while T. forsythia and P. gingivalis both were most sensitive organisms against chlorhexidine gluconate with MIC values of 0.00781 mg/ml. M. alba possess good antibacterial activity against A. actinomycetemcomitans, P. gingivalis and T. forsythia and thus would be beneficial for the prevention and treatment of periodontal disease. However, chlorhexidine gluconate was found to be more effective when compared to M. alba.

Bacterial Heat Shock Protein GroEL (Hsp64) Exerts Immunoregulatory Effects on T Cells by Utilizing Apoptosis

PubMed Central

Nalbant, Ayten; Kant, Melis

2016-01-01

Aggregatibacter actinomycetemcomitans (Aa) expresses a 64-kDa GroEL protein belonging to the heat shock family of proteins. This protein has been shown to influence human host cells, but the apoptotic capacity of the GroEL protein regarding T cells is not yet known. The purpose of this study was to investigate the ability of A. actinomycetemcomitans GroEL (AaGroEL) protein to induce human peripheral blood T-cell apoptosis. Endogenous, purified AaGroEL protein was used as an antigen. In AaGroEL-treated T cells, the data indicated that phosphatidylserine exposure, an early apoptotic event, was dose- and time-dependent. The AaGroEL-treated T cells were also positive for active caspase-3 in a dose-dependent manner. The rate of AaGroEL-induced apoptosis was suppressed by the addition of the general caspase inhibitor Z-VAD-FMK. Furthermore, cleaved caspase-8 bands (40/36 kDa and 23 kDa) were identified in cells responding to AaGroEL. DNA fragmentation was also detected in the AaGroEL-treated T cells. Overall, we demonstrated that the endogenous GroEL from A. actinomycetemcomitans has the capacity to induce T-cell apoptosis. PMID:27736933

Assessment of Photodynamic Inactivation against Periodontal Bacteria Mediated by a Chitosan Hydrogel in a 3D Gingival Model.

PubMed

Peng, Po-Chun; Hsieh, Chien-Ming; Chen, Chueh-Pin; Tsai, Tsuimin; Chen, Chin-Tin

2016-11-01

Chitosan hydrogels containing hydroxypropyl methylcellulose (HPMC) and toluidine blue O were prepared and assessed for their mucoadhesive property and antimicrobial efficacy of photodynamic inactivation (PDI). Increased HPMC content in the hydrogels resulted in increased mucoadhesiveness. Furthermore, we developed a simple In Vitro 3D gingival model resembling the oral periodontal pocket to culture the biofilms of Staphylococcus aureus ( S. aureus ), Aggregatibacter actinomycetemcomitans ( A. actinomycetemcomitans ), and Porphyromonas gingivalis ( P. gingivalis ). The PDI efficacy of chitosan hydrogel was examined against periodontal biofilms cultured in this 3D gingival model. We found that the PDI effectiveness was limited due to leaving some of the innermost bacteria alive at the non-illuminated site. Using this 3D gingival model, we further optimized PDI procedures with various adjustments of light energy and irradiation sites. The PDI efficacy of the chitosan hydrogel against periodontal biofilms can significantly improve via four sides of irradiation. In conclusion, this study not only showed the clinical applicability of this chitosan hydrogel but also the importance of the light irradiation pattern in performing PDI for periodontal disease.

Assessment of Photodynamic Inactivation against Periodontal Bacteria Mediated by a Chitosan Hydrogel in a 3D Gingival Model

PubMed Central

Peng, Po-Chun; Hsieh, Chien-Ming; Chen, Chueh-Pin; Tsai, Tsuimin; Chen, Chin-Tin

2016-01-01

Chitosan hydrogels containing hydroxypropyl methylcellulose (HPMC) and toluidine blue O were prepared and assessed for their mucoadhesive property and antimicrobial efficacy of photodynamic inactivation (PDI). Increased HPMC content in the hydrogels resulted in increased mucoadhesiveness. Furthermore, we developed a simple In Vitro 3D gingival model resembling the oral periodontal pocket to culture the biofilms of Staphylococcus aureus (S. aureus), Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), and Porphyromonas gingivalis (P. gingivalis). The PDI efficacy of chitosan hydrogel was examined against periodontal biofilms cultured in this 3D gingival model. We found that the PDI effectiveness was limited due to leaving some of the innermost bacteria alive at the non-illuminated site. Using this 3D gingival model, we further optimized PDI procedures with various adjustments of light energy and irradiation sites. The PDI efficacy of the chitosan hydrogel against periodontal biofilms can significantly improve via four sides of irradiation. In conclusion, this study not only showed the clinical applicability of this chitosan hydrogel but also the importance of the light irradiation pattern in performing PDI for periodontal disease. PMID:27809278

Clinical and microbiological effects of levofloxacin in the treatment of chronic periodontitis: a randomized, placebo-controlled clinical trial.

PubMed

Pradeep, Avani R; Singh, Sonender P; Martande, Santosh S; Naik, Savitha B; N, Priyanka; Kalra, Nitish; Suke, Deepak K

2015-08-01

The aim of the present study was to evaluate the clinical and microbiological effect of systemic levofloxacin (LFX) as an adjunct to scaling and root planing (SRP) in patients with chronic periodontitis (CP). Sixty-five patients with CP were randomly divided into a test (n = 33, SRP and LFX 500 mg, once daily [o.d.]) and a control group (n = 32, SRP and placebo, o.d.). Plaque index (PI), gingival index (GI), percentage of sites with bleeding on probing (%BoP), probing depth (PD), and clinical attachment level (CAL) were recorded at baseline, 10 days, and 1-, 3-, and 6-month intervals. The percentage of sites positive for Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), Porphyromonas gingivalis, and Tannerella forsythia were recorded at baseline and at 3 and 6 months. Patients receiving LFX showed statistically-significant improvements in mean PD and CAL. The intergroup difference in PI, GI, and%BoP was not significant at any interval. There was a reduction in the percentage of sites positive for periodontopathic bacteria over the duration of the study in both groups, and a statistically-significant reduction in the number of sites positive for A. actinomycetemcomitans in the LFX group (P < 0.001). Levofloxacin was found to significantly improve the clinical and microbiological parameters in CP individuals. © 2014 Wiley Publishing Asia Pty Ltd.

Non-surgical periodontal therapy decreases serum elastase levels in aggressive but not in chronic periodontitis.

PubMed

Eickholz, Peter; Siegelin, Yasemin; Scharf, Susanne; Schacher, Beate; Oremek, Gerhard M; Sauer-Eppel, Hildegund; Schubert, Ralf; Wohlfeil, Martin

2013-04-01

Assessment of the effect of non-surgical periodontal therapy (SRP) on serum inflammatory parameters in patients with untreated aggressive (AgP) and chronic (ChP) periodontitis. Overall, 31 ChP and 29 AgP were examined clinically prior to and 12 weeks after SRP (subgingival scaling of all pockets within 2 days) with systemic antibiotics for patients positive for Aggregatibacter actinomycetemcomitans (14 AgP, 9 ChP). Blood was sampled prior to, one day, 6, and 12 weeks after the first SRP visit. Serum elastase, C-reactive protein (CRP), lipopolysaccharide-binding protein (LBP), interleukin (IL) 6, 8, and leukocyte counts were assessed. At baseline, serum elastase, CRP, and LBP were significantly (p < 0.01) higher in AgP than ChP. Serum elastase, CRP, LBP, and IL-6 were significantly (p < 0.001) elevated one day after scaling in both groups. Both groups showed significant clinical improvement (p < 0.001). A significant difference was observed regarding change of serum elastase 12 weeks after SRP between AgP and ChP (p = 0.015). Multiple regression analysis revealed AgP, African origin, and bleeding on probing to be associated with more pronounced elastase reduction. CRP reduction was associated with African origin, systemic antibiotics, and baseline probing pocket depth. SRP results in serum elastase reduction in AgP but not in ChP. © 2013 John Wiley & Sons A/S.

Probiotics and periodontal health

PubMed Central

2011-01-01

Periodontitis is one of the most common chronic inflammatory diseases. The etiology is clearly bacterial and a number of putative bacterial pathogens have been associated with the disease, including Aggregatibacter actinomycetemcomitans, Tannerella forsythus and Porphyromonas gingivalis. Comparatively, little attention has been paid to the identification of health-associated and potentially beneficial bacterial species that may reside in the gingival sulcus. Probiotic technology represents a breakthrough approach to maintaining oral health by using natural beneficial bacteria, commonly found in healthy mouths, to provide a natural defense against those bacteria which are thought to be harmful to teeth and gums. This article endeavors to introduce the concepts of probiotics in periodontics. PMID:22514571

Probiotics and periodontal health.

PubMed

Gupta, G

2011-11-14

Periodontitis is one of the most common chronic inflammatory diseases. The etiology is clearly bacterial and a number of putative bacterial pathogens have been associated with the disease, including Aggregatibacter actinomycetemcomitans, Tannerella forsythus and Porphyromonas gingivalis. Comparatively, little attention has been paid to the identification of health-associated and potentially beneficial bacterial species that may reside in the gingival sulcus. Probiotic technology represents a breakthrough approach to maintaining oral health by using natural beneficial bacteria, commonly found in healthy mouths, to provide a natural defense against those bacteria which are thought to be harmful to teeth and gums. This article endeavors to introduce the concepts of probiotics in periodontics.

Brain abscess due to Aggregatibacter aphrophilus and Bacteroides uniformis.

PubMed

Bogdan, Maja; Zujić Atalić, Vlasta; Hećimović, Ivan; Vuković, Dubravka

2015-01-01

The aim of this report was to describe the occurrence of a bacterial brain abscess in a healthy individual, without any predisposing condition. A thirteen-year old boy was admitted to the Department of Neurosurgery after the onset of vomiting, headache and dizziness. A neurological deficit was detected during the physical examination so urgent magnetic resonance imaging of the brain was performed, revealing an intrahemispheric, right positioned solitary expansive mass with ring enhancement. Purulent material was obtained during osteoplastic craniotomy with total extirpation of the brain abscess. Aggregatibacter aphrophilus and Bacteroides uniformis were isolated. The patient's general condition improved and the neurological deficit subsided as a result of the prompt recognition and treatment of this life threatening condition. To achieve a favourable clinical outcome, prompt recognition and surgical treatment of a brain abscess are of primary importance,followed by administration of appropriate antimicrobial therapy. To our best knowledge, this is the first report of this combination of microorganisms as the cause of a brain abscess. Copyright © 2015 by Academy of Sciences and Arts of Bosnia and Herzegovina.

Protective effects of the angiotensin type 1 receptor antagonist losartan in infection-induced and arthritis-associated alveolar bone loss.

PubMed

Queiroz-Junior, C M; Silveira, K D; de Oliveira, C R; Moura, A P; Madeira, M F M; Soriani, F M; Ferreira, A J; Fukada, S Y; Teixeira, M M; Souza, D G; da Silva, T A

2015-12-01

The angiotensin type 1 (AT1) receptor has been implicated in the pathogenesis of inflammatory bone disorders. This study aimed to investigate the effect of an AT1 receptor antagonist in infection-induced and arthritis-associated alveolar bone loss in mice. Mice were subjected to Aggregatibacter actinomycetemcomitans oral infection or antigen-induced arthritis and treated daily with 10 mg/kg of the prototype AT1 antagonist, losartan. Treatment was conducted for 30 d in the infectious condition and for 17 d and 11 d in the preventive or therapeutic regimens in the arthritic model, respectively. The mice were then killed, and the maxillae, serum and knee joints were collected for histomorphometric and immunoenzymatic assays. In vitro osteoclast assays were performed using RAW 264.7 cells stimulated with A. actinomycetemcomitans lipopolysacharide (LPS). Arthritis and A. actinomycetemcomitans infection triggered significant alveolar bone loss in mice and increased the levels of myeloperoxidase and of TRAP(+) osteoclasts in periodontal tissues. Losartan abolished such a phenotype, as well as the arthritis joint inflammation. Both arthritis and A. actinomycetemcomitans conditions were associated with the release of tumor necrosis factor alpha (TNF-α), interferon-gamma, interleukin-17 and chemokine (C-X-C motif) ligand 1 and an increased RANKL/osteoprotegerin ratio in periodontal tissues, but such expression decreased after losartan treatment, except for TNF-α. The therapeutic approach was as beneficial as the preventive one. In vitro, losartan prevented LPS-induced osteoclast differentiation and activity. The blockade of AT1 receptor exerts anti-inflammatory and anti-osteoclastic effects, thus protecting periodontal tissues in distinct pathophysiological conditions of alveolar bone loss. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Cloning and sequence analysis of recombinant fusion gene of Escherichia coli heat-liable enterotoxin B subunit and Actinobacillus actinomycetemcomitans fimbria associative protein].

PubMed

Li, Yi; Sun, Hong-chen; Guo, Xue-jun; Feng, Shu-zhang

2005-02-01

To clone the recombinant fusion gene of Escherichia coli heat-liable enterotoxin B subunit (Ltb) and Actinobacillus actinomycetemcomitans fimbria associative protein (Fap). Two couples of primers were designed for PCR according to the known sequence of ltb and fap. The ltb and fap gene were obtained by amplification PCR technique from plasmid EWD299 of Escherichia coli and Actinobacillus actinomycetemcomitans 310 DNA respectively, and fused them by PCR. The fusion gene ltb-fap were cloning into plasmid pET28a(+). The recombined plasmid pET28a ltb-fap was transformed into Escherichia coli DH5alpha. The recombinant was screened and identified by restriction enzyme and PCR. The cloned gene was sequenced. The ltb-fap about 531bp in size was obtained successfully, and identified by PCR, restrictive enzyme and sequence analysis. The vector of pET28a ltb-fap was obtained.

Lipopolysaccharide-binding protein, lipopolysaccharide, and soluble CD14 in sepsis of critically ill neonates and children.

PubMed

Pavcnik-Arnol, Maja; Hojker, Sergej; Derganc, Metka

2007-06-01

To compare the diagnostic accuracy of lipopolysaccharide-binding protein (LBP) for sepsis in critically ill neonates and children with the two markers participating in the same inflammatory pathway, lipopolysaccharide and soluble CD14. Prospective, observational study in a multidisciplinary neonatal and pediatric intensive care unit. 47 critically ill neonates and 49 critically ill children with systemic inflammatory response syndrome (SIRS) and suspected sepsis, classified into two groups: those with and those without sepsis. Serum LBP, lipopolysaccharide, soluble CD14, C-reactive protein, and procalcitonin were measured on 2 consecutive days. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and predictive values were evaluated. AUC for LBP on the first day of suspected infection was 0.97 in neonates aged under 48 h, 0.93 in neonates over 48 h and 0.82 in children. AUCs for lipopolysaccharide and soluble CD14 were 0.77 and 0.74 in neonates under 48 h, 0.53 and 0.76 in neonates over 48 h, and 0.72 and 0.53 in children. AUCs for procalcitonin and C-reactive protein were 0.65 and 0.89 in neonates under 48 h, 0.65 and 0.91 in neonates over 48 h, and 0.76 and 0.69 in children. In critically ill neonates and children LBP concentration on the first day of suspected sepsis is a better marker of sepsis than lipopolysaccharide, soluble CD14, procalcitonin, and in neonates younger than 48 h and children, also a better marker than C-reactive protein. Lipopolysaccharide and soluble CD14 are not suitable markers for the differentiation of infectious and noninfectious SIRS.

Rheumatoid arthritis is an autoimmune disease caused by periodontal pathogens

PubMed Central

Ogrendik, Mesut

2013-01-01

A statistically significant association between periodontal disease (PD) and systemic diseases has been identified. Rheumatoid arthritis (RA), which is a chronic inflammatory joint disease, exhibits similar characteristics and pathogenesis to PD. The association between RA and PD has been investigated, and numerous publications on this subject exist. Approximately 20 bacterial species have been identified as periodontal pathogens, and these organisms are linked to various types of PD. The most analyzed species of periodontopathic bacteria are Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans. Antibodies and DNA from these oral pathogens have been isolated from the sera and synovial fluids of RA patients. This rapid communication describes the role of periodontal pathogens in the etiopathogenesis of RA. PMID:23737674

Competition between yogurt probiotics and periodontal pathogens in vitro.

PubMed

Zhu, Yunwo; Xiao, Liying; Shen, Da; Hao, Yuqing

2010-09-01

To investigate the competition between probiotics in bio-yogurt and periodontal pathogens in vitro. The antimicrobial activity of bio-yogurt was studied by agar diffusion assays, using eight species of putative periodontal pathogens and a 'protective bacteria' as indicator strains. Four probiotic bacterial species (Lactobacillus bulgaricus, Streptococcus thermophilus, Lactobacillus acidophilus, and Bifidobacterium) were isolated from yogurt and used to rate the competitive exclusion between probiotics and periodontal pathogens. Fresh yogurt inhibited all the periodontal pathogens included in this work, showing inhibition zones ranging from 9.3 (standard deviation 0.6) mm to 17.3 (standard deviation 1.7) mm, whereas heat-treated yogurt showed lower antimicrobial activity. In addition, neither fresh yogurt nor heat-treated yogurt inhibited the 'protective bacteria', Streptococcus sanguinis. The competition between yogurt probiotics and periodontal pathogens depended on the sequence of inoculation. When probiotics were inoculated first, Bifidobacterium inhibited Porphyromonas gingivalis, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans, Porphyromonas circumdentaria, and Prevotella nigrescens; L. acidophilus inhibited P. gingivalis, A. actinomycetemcomitans, P. circumdentaria, P. nigrescens, and Peptostreptococcus anaerobius; L. bulgaricus inhibited P. gingivalis, A. actinomycetemcomitans, and P. nigrescens; and S. thermophilus inhibited P. gingivalis, F. nucleatum, and P. nigrescens. However, their antimicrobial properties were reduced when both species (probiotics and periodontal pathogens) were inoculated simultaneously. When periodontal pathogens were inoculated first, Prevotella intermedia inhibited Bifidobacterium and S. thermophilus. The results demonstrated that bio-yogurt and the probiotics that it contains are capable of inhibiting specific periodontal pathogens but have no effect on the periodontal protective bacteria.

Proinflammatory effect in whole blood by free soluble bacterial components released from planktonic and biofilm cells

PubMed Central

Oscarsson, Jan; Karched, Maribasappa; Thay, Bernard; Chen, Casey; Asikainen, Sirkka

2008-01-01

Background Aggregatibacter actinomycetemcomitans is an oral bacterium associated with aggressive forms of periodontitis. Increasing evidence points to a link between periodontitis and cardiovascular diseases, however, the underlying mechanisms are poorly understood. This study investigated the pathogenic potential of free-soluble surface material, released from live planktonic and biofilm A. actinomycetemcomitans cells. Results By employing an ex vivo insert model (filter pore size 20 nm) we demonstrated that the A. actinomycetemcomitans strain D7S and its derivatives, in both planktonic and in biofilm life-form, released free-soluble surface material independent of outer membrane vesicles. This material clearly enhanced the production of several proinflammatory cytokines (IL-1β, TNF-α, IL-6, IL-8, MIP-1β) in human whole blood, as evidenced by using a cytokine antibody array and dissociation-enhanced-lanthanide-fluorescent-immunoassay. In agreement with this, quantitative real-time PCR indicated a concomitant increase in transcription of each of these cytokine genes. Experiments in which the LPS activity was blocked with polymyxin B showed that the stimulatory effect was only partly LPS-dependent, suggesting the involvement of additional free-soluble factors. Consistent with this, MALDI-TOF-MS and immunoblotting revealed release of GroEL-like protein in free-soluble form. Conversely, the immunomodulatory toxins, cytolethal distending toxin and leukotoxin, and peptidoglycan-associated lipoprotein, appeared to be less important, as evidenced by studying strain D7S cdt/ltx double, and pal single mutants. In addition to A. actinomycetemcomitans a non-oral species, Escherichia coli strain IHE3034, tested in the same ex vivo model also released free-soluble surface material with proinflammatory activity. Conclusion A. actinomycetemcomitans, grown in biofilm and planktonic form, releases free-soluble surface material independent of outer membrane vesicles, which

Proinflammatory effect in whole blood by free soluble bacterial components released from planktonic and biofilm cells.

PubMed

Oscarsson, Jan; Karched, Maribasappa; Thay, Bernard; Chen, Casey; Asikainen, Sirkka

2008-11-27

Aggregatibacter actinomycetemcomitans is an oral bacterium associated with aggressive forms of periodontitis. Increasing evidence points to a link between periodontitis and cardiovascular diseases, however, the underlying mechanisms are poorly understood. This study investigated the pathogenic potential of free-soluble surface material, released from live planktonic and biofilm A. actinomycetemcomitans cells. By employing an ex vivo insert model (filter pore size 20 nm) we demonstrated that the A. actinomycetemcomitans strain D7S and its derivatives, in both planktonic and in biofilm life-form, released free-soluble surface material independent of outer membrane vesicles. This material clearly enhanced the production of several proinflammatory cytokines (IL-1 beta, TNF-alpha, IL-6, IL-8, MIP-1 beta) in human whole blood, as evidenced by using a cytokine antibody array and dissociation-enhanced-lanthanide-fluorescent-immunoassay. In agreement with this, quantitative real-time PCR indicated a concomitant increase in transcription of each of these cytokine genes. Experiments in which the LPS activity was blocked with polymyxin B showed that the stimulatory effect was only partly LPS-dependent, suggesting the involvement of additional free-soluble factors. Consistent with this, MALDI-TOF-MS and immunoblotting revealed release of GroEL-like protein in free-soluble form. Conversely, the immunomodulatory toxins, cytolethal distending toxin and leukotoxin, and peptidoglycan-associated lipoprotein, appeared to be less important, as evidenced by studying strain D7S cdt/ltx double, and pal single mutants. In addition to A. actinomycetemcomitans a non-oral species, Escherichia coli strain IHE3034, tested in the same ex vivo model also released free-soluble surface material with proinflammatory activity. A. actinomycetemcomitans, grown in biofilm and planktonic form, releases free-soluble surface material independent of outer membrane vesicles, which induces proinflammatory

Gram-positive bacteria as an antigen topically applied into gingival sulcus of immunized rat accelerates periodontal destruction.

PubMed

Nagano, F; Kaneko, T; Yoshinaga, Y; Ukai, T; Kuramoto, A; Nakatsu, S; Oshino, K; Ichimura, I; Hara, Y

2013-08-01

Periodontitis is generally accepted to relate to gram-negative bacteria, and the host defense system influences its onset and progression. However, little is known about the relation between gram-positive bacteria and periodontitis. In this study, we topically applied gram-positive and gram-negative bacterial suspensions to the gingival sulcus in rats after immunization, and then histopathologically examined their influence on periodontal destruction. Rats previously immunized with heat-treated and sonicated Staphylococcus aureus or Aggregatibacter actinomycetemcomitans were used as immunized groups. The non-immunized group received only sterile phosphate-buffered saline. In each animal, S. aureus or A. actinomycetemcomitans suspension was applied topically to the palatal gingival sulcus of first molars every 24 h for 10 d. Blood samples were collected and the serum level of anti-S. aureus or anti-A. actinomycetemcomitans immunoglobulin G (IgG) antibodies was determined by enzyme-linked immunosorbent assay. The first molar regions were resected and observed histopathologically. Osteoclasts were stained with tartrate-resistant acid phosphatase (TRAP). The formation of immune complexes was confirmed by immunohistological staining of C1qB. Serum levels of anti-S. aureus and anti-A. actinomycetemcomitans IgG antibodies in the immunized groups were significantly higher than those in the non-immunized groups were. The loss of attachment, increase in apical migration of the junctional epithelium, and decreases in alveolar bone level and number of TRAP-positive multinuclear cells in each immunized group were significantly greater than in each non-immunized group. The presence of C1qB was observed in the junctional epithelium and adjacent connective tissue in the immunized groups. Heat-treated and sonicated S. aureus and A. actinomycetemcomitans induced attachment loss in rats immunized with their suspensions. Our results suggest that not only gram-negative but also gram

Lipopolysaccharides in liver injury: molecular mechanisms of Kupffer cell activation.

PubMed

Su, Grace L

2002-08-01

Endogenous gut-derived bacterial lipopolysaccharides have been implicated as important cofactors in the pathogenesis of liver injury. However, the molecular mechanisms by which lipopolysaccharides exert their effect are not entirely clear. Recent studies have pointed to proinflammatory cytokines such as tumor necrosis factor-alpha as mediators of hepatocyte injury. Within the liver, Kupffer cells are major sources of proinflammatory cytokines that are produced in response to lipopolysaccharides. This review will focus on three important molecular components of the pathway by which lipopolysaccharides activate Kupffer cells: CD14, Toll-like receptor 4, and lipopolysaccharide binding protein. Within the liver, lipopolysaccharides bind to lipopolysaccharide binding protein, which then facilitates its transfer to membrane CD14 on the surface of Kupffer cells. Signaling of lipopolysaccharide through CD14 is mediated by the downstream receptor Toll-like receptor 4 and results in activation of Kupffer cells. The role played by these molecules in liver injury will be examined.

Quantification of periodontal pathogens in vascular, blood, and subgingival samples from patients with peripheral arterial disease or abdominal aortic aneurysms.

PubMed

Figuero, Elena; Lindahl, Christeel; Marín, María José; Renvert, Stefan; Herrera, David; Ohlsson, Ola; Wetterling, Thomas; Sanz, Mariano

2014-09-01

The aim of this investigation is to quantify periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Campylobacter rectus, and Tannerella forsythia) in vascular, blood, and subgingival samples. As a secondary objective, two molecular bacterial identification methods (nested polymerase chain reaction [PCR] and quantitative PCR [qPCR]) are compared. Seventy consecutive patients provided a vascular lesion, a blood sample, and 36 subgingival samples. Bacterial DNA was extracted, and qPCR was used to determine the prevalence and amounts of the target pathogens in each sample. Nested PCR was performed only in the samples from vascular lesions. Periodontal examination was performed in 42 patients. Mann-Whitney U or χ(2) tests were used to compare microbiologic results according to periodontal diagnosis. All targeted periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, T. forsythia, or C. rectus) were detected in subgingival samples, with a prevalence rate of 72.2%, 47.2%, 74.3%, and 82.9%, respectively. In 7.1% and 11.4% of vascular and blood samples, bacterial DNA was detected. One patient was positive for A. actinomycetemcomitans in the three types of samples. No differences were found in the levels of targeted bacteria when comparing patients with and without periodontitis. Prevalence rates obtained with nested PCR were significantly higher than those obtained with qPCR. The presence of A. actinomycetemcomitans was demonstrated in vascular, blood, and subgingival samples in one of 36 patients. These results, although with a very low frequency, may support the hypothesis of a translocation of periodontal pathogens from subgingival microbiota to the bloodstream and then to atheromatous plaques in carotid or other peripheral arteries. Nested PCR is not an adequate method for identifying DNA of periodontal pathogens in low quantities because of the high number of false-negative results.

Inhibition of host extracellular matrix destructive enzyme production and activity by a high-molecular-weight cranberry fraction.

PubMed

Bodet, C; Chandad, F; Grenier, D

2007-04-01

Periodontal diseases are a group of inflammatory disorders that are initiated by specific gram-negative bacteria and lead to connective tissue destruction. Proteolytic enzymes, including matrix metalloproteinases (MMPs) and elastase, produced by resident and inflammatory cells in response to periodontopathogens and their products, play a major role in gingival tissue destruction. The aim of this study was to investigate the effect of a high-molecular-weight fraction prepared from cranberry juice concentrate on MMP-3, MMP-9 and elastase activities, as well as on MMP production by human cells stimulated with lipopolysaccharide of Actinobacillus actinomycetemcomitans. MMP-3 and MMP-9 production by gingival fibroblasts and macrophages treated with the cranberry fraction and then stimulated with lipopolysaccharide was measured by enzyme-linked immunosorbent assay. MMP-3, MMP-9 and elastase activities in the presence of the cranberry fraction were evaluated using colorimetric or fluorogenic substrates. The changes in expression and phosphorylation state of fibroblast intracellular signaling proteins induced by A. actinomycetemcomitans lipopolysaccharide and the cranberry fraction were characterized by antibody microarrays. The lipopolysaccharide-induced MMP-3 and MMP-9 responses of fibroblasts and macrophages were inhibited in a dose-dependent manner by the cranberry fraction. This fraction was found to inhibit fibroblast intracellular signaling proteins, a phenomenon that may lead to a down-regulation of activating protein-1 activity. MMP-3, MMP-9 and elastase activities were also efficiently inhibited by the cranberry fraction, even when it was used at low concentrations. These results suggest that cranberry compounds offer promising perspectives for the development of novel host-modulating strategies for an adjunctive treatment of periodontitis.

Periodontopathogen profile of healthy and oral lichen planus patients with gingivitis or periodontitis

PubMed Central

Seckin Ertugrul, Abdullah; Arslan, Ugur; Dursun, Recep; Sezgin Hakki, Sema

2013-01-01

Oral lichen planus (OLP) is a chronic inflammatory disease that is frequently detected in oral tissues. The aim of our study was to identify the prevalence of the detection of periodontopathogenic microorganisms (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Treponema denticola in OLP patients and to compare with this prevalence of periodontopathogenic microorganisms in healthy non-OLP patients. Our study included 27 (18 chronic periodontitis (OLPP) and 9 gingivitis (OLPG)) patients diagnosed with OLP along with 26 (13 chronic periodontitis (HP) and 13 gingivitis (HG)) healthy non-OLP patients. The multiplex polymerase chain reaction (PCR) with subsequent reverse hybridization method (micro-IDent) was used for identifying periodontopathogenic microorganisms present in subgingival plaque samples. The percentages of detection for A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola in subgingival plaque samples taken from OLP patients (OLPG and OLPP) were 18.5%, 85.1%, 81.4%, 88.8% and 74%, respectively. Meanwhile, in the non-OLP patients (HG and HP), these values were 7.6%, 50%, 46.1%, 73% and 57.7%, respectively. Thus, comparing the non-OLP groups with the OLP groups, the periodontopathogens' percentages of detection in the OLP groups were higher than those in the non-OLP groups. According to our study results, OLP patients have higher levels of infection with A. actinomycetemcomitans, P. gingivalis, P. intermedia, T. forsythia and T. denticola than non-OLP patients. We argue that the high percentages in patients with OLP may help identify the importance of periodontopathogenic microorganisms in the progress of periodontal diseases of OLP. PMID:23743616

Development of novel electrospun dual-drug fiber mats loaded with a combination of ampicillin and metronidazole.

PubMed

Schkarpetkin, Dennis; Reise, Markus; Wyrwa, Ralf; Völpel, Andrea; Berg, Albrecht; Schweder, Martina; Schnabelrauch, Matthias; Watts, David C; Sigusch, Bernd W

2016-08-01

Our study was performed with the aim of preparing electrospun polylactide fibers with a combination of ampicillin (AMP) and metronidazole (MNZ) and investigating their drug release behavior and the antibacterial effect on Aggregatibacter actinomycetemcomitans and other oral pathogens. AMP and MNZ were integrated as a combination in two separate fibers (dual fiber mats - DFW mix) of electrospun PLA fiber mats by means of multijet electrospinning and in a single fiber (single fiber mats - SFW mix). HPLC (high-performance liquid chromatography) was used to measure the released drug quantities. Agar diffusion tests were used to determine the antibacterial effect of the eluates on A. actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis and Enterococcus faecalis. The neutral red test was made to examine the cytocompatibility of the eluates with human gingival fibroblasts (hGFs). The release of the active agents varied with the antibiotic concentrations initially used in the fiber mats, but also with the distribution of the active agents in one or two fibers. Of the total quantity of MNZ (AMP), the SFW mix fiber mats released >60% (>70%) within a span of 5min, and 76% (71%) after 96h. With these drug concentrations released by the fiber mats (≥5m%), an antibacterial effect was achieved on A. actinomycetemcomitans and on all other species tested. Fiber mats and their eluates have no cytotoxic influence on human gingival fibroblasts (hGFs). Electrospun AMP/MNZ-loaded polymer fibers are a potential drug delivery system for use in periodontal and endodontic infections. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Effect of Lactobacillus rhamnosus and Bifidobacterium lactis on gingival health, dental plaque, and periodontopathogens in adolescents: a randomised placebo-controlled clinical trial.

PubMed

Alanzi, A; Honkala, S; Honkala, E; Varghese, A; Tolvanen, M; Söderling, E

2018-04-10

To determine the effect of a probiotic combination of Lactobacillus rhamnosus GG (LGG) and Bifidobacterium lactis BB-12 on the gingival health, dental plaque accumulation, and the oral carriage of four putative periodontal pathogens in healthy adolescents. 108 schoolboys, aged 13-15 years, participated in this study. They were divided into two groups: probiotics (n=54) and placebo (n=54). Both groups received two probiotic-laced or placebo lozenges twice a day during a four-week period. Plaque Index (PI) and Gingival Index (GI) were recorded at baseline and after four weeks. Salivary and plaque carriage of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum were also monitored likewise. 101 subjects completed the study. A statistically significant reduction in GI was seen in the probiotic group as compared to the placebo group (P=0.012). A reduction in PI was found for both groups, with no difference observed between the groups after intervention (P=0.819). Probiotic lozenges significantly reduced levels of A. actinomycetemcomitans and F. nucleatum in saliva and plaque (P<0.05) and levels of P. gingivalis in plaque (P<0.05), while no significant changes were found in the control group. A significant reduction (P<0.001) was also noted in the total salivary bacterial counts of the test group. The short-term daily consumption of LGG and BB-12 probiotic lozenges improved the gingival health in adolescents and decreased the microbial counts of A. actinomycetemcomitans, and P. gingivalis. Hence probiotic supplements may serve as a simple adjunct to standard oral care for promoting the oral health in adolescents.

Structure of bacterial lipopolysaccharides.

PubMed

Caroff, Martine; Karibian, Doris

2003-11-14

Bacterial lipopolysaccharides are the major components of the outer surface of Gram-negative bacteria They are often of interest in medicine for their immunomodulatory properties. In small amounts they can be beneficial, but in larger amounts they may cause endotoxic shock. Although they share a common architecture, their structural details exert a strong influence on their activity. These molecules comprise: a lipid moiety, called lipid A, which is considered to be the endotoxic component, a glycosidic part consisting of a core of approximately 10 monosaccharides and, in "smooth-type" lipopolysaccharides, a third region, named O-chain, consisting of repetitive subunits of one to eight monosaccharides responsible for much of the immunospecificity of the bacterial cell.

Transformation of Human Erythrocyte Shape by Endotoxic Lipopolysaccharide

PubMed Central

Warren, John R.; Harris, Alan S.; Wallas, Charles H.

1983-01-01

Human erythrocytes were observed to undergo a discocyte to echinocyte to spheroechinocyte shape transformation during brief incubation with endotoxic lipopolysaccharide. It was concluded that lipopolysaccharide-membrane interactions alter the curvature of erythrocyte membranes. Images PMID:6822423

The pathogenic persona of community-associated oral streptococci.

PubMed

Whitmore, Sarah E; Lamont, Richard J

2011-07-01

The mitis group streptococci (MGS) are widespread in the oral cavity and are traditionally associated with oral health. However, these organisms have many attributes that contribute to the development of pathogenic oral communities. MGS adhere rapidly to saliva-coated tooth surfaces, thereby providing an attachment substratum for more overtly pathogenic organisms such as Porphyromonas gingivalis, and the two species assemble into heterotypic communities. Close physical association facilitates physiologic support, and pathogens such as Aggregatibacter actinomycetemcomitans display resource partitioning to favour carbon sources generated by streptococcal metabolism. MGS exchange information with community members through a number of interspecies signalling systems including AI-2 and contact dependent mechanisms. Signal transduction systems induced in P. gingivalis are based on protein dephosphorylation mediated by the tyrosine phosphatase Ltp1, and converge on a LuxR-family transcriptional regulator, CdhR. Phenotypic responses in P. gingivalis include regulation of hemin uptake systems and gingipain activity, processes that are intimately linked to the virulence of the organism. Furthermore, communities of S. gordonii with P. gingivalis or with A. actinomycetemcomitans are more pathogenic in animal models than the constituent species alone. We propose that MGS should be considered accessory pathogens, organisms whose pathogenic potential only becomes evident in the context of a heterotypic microbial community. © 2011 Blackwell Publishing Ltd.

Antimicrobial activity of platelet-rich plasma and other plasma preparations against periodontal pathogens.

PubMed

Yang, Li-Chiu; Hu, Suh-Woan; Yan, Min; Yang, Jaw-Ji; Tsou, Sing-Hua; Lin, Yuh-Yih

2015-02-01

In addition to releasing a pool of growth factors during activation, platelets have many features that indicate their role in the anti-infective host defense. The antimicrobial activities of platelet-rich plasma (PRP) and related plasma preparations against periodontal disease-associated bacteria were evaluated. Four distinct plasma fractions were extracted in the formulation used commonly in dentistry and were tested for their antibacterial properties against three periodontal bacteria: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum. The minimum inhibitory concentration of each plasma preparation was determined, and in vitro time-kill assays were used to detect their abilities to inhibit bacterial growth. Bacterial adhesion interference and the susceptibility of bacterial adherence by these plasma preparations were also conducted. All plasma preparations can inhibit bacterial growth, with PRP showing the superior activity. Bacterial growth inhibition by PRP occurred in the first 24 hours after application in the time-kill assay. PRP interfered with P. gingivalis and A. actinomycetemcomitans attachment and enhanced exfoliation of attached P. gingivalis but had no influences on F. nucleatum bacterial adherence. PRP expressed antibacterial properties, which may be attributed to platelets possessing additional antimicrobial molecules. The application of PRP on periodontal surgical sites is advisable because of its regenerative potential and its antibacterial effects.

Antibacterial activity of moxifloxacin on bacteria associated with periodontitis within a biofilm.

PubMed

Tsaousoglou, Phoebus; Nietzsche, Sandor; Cachovan, Georg; Sculean, Anton; Eick, Sigrun

2014-02-01

The activity of moxifloxacin was compared with ofloxacin and doxycycline against bacteria associated with periodontitis within a biofilm (single strain and mixed population) in vitro. MICs and minimal bactericidal concentrations (MBCs) of moxifloxacin, ofloxacin and doxycyline were determined against single strains and mixed populations in a planktonic state. Single-species biofilms of two Porphyromonas gingivalis and two Aggregatibacter actinomycetemcomitans strains and a multispecies biofilm consisting of 12 species were formed for 3 days. The minimal biofilm eradication concentrations (MBECs) were determined after exposing the biofilms to the antibacterials (0.002-512 µg ml(-1)) for 18 h, addition of nutrient broth for 3 days and subsequent subcultivation. Photographs were taken using confocal laser-scanning microscopy and scanning electron microscopy. The MICs and MBCs did not differ between ofloxacin and moxifloxacin against A. actinomycetemcomitans, whilst moxifloxacin was more active than the other tested antibacterials against anaerobes and the mixed population. The single-species biofilms were eradicated by moderate concentrations of the antibacterials, and the lowest MBECs were always found for moxifloxacin (2-8 µg ml(-1)). MBECs against the multispecies biofilms were 128, >512 and >512 µg ml(-1) for moxifloxacin, ofloxacin and doxycycline, respectively. In summary, moxifloxacin in a topical formulation may have potential as an adjunct to mechanical removal of the biofilms.

Epithelial cell pro-inflammatory cytokine response differs across dental plaque bacterial species.

PubMed

Stathopoulou, Panagiota G; Benakanakere, Manjunatha R; Galicia, Johnah C; Kinane, Denis F

2010-01-01

The dental plaque is comprised of numerous bacterial species, which may or may not be pathogenic. Human gingival epithelial cells (HGECs) respond to perturbation by various bacteria of the dental plaque by production of different levels of inflammatory cytokines, which is a putative reflection of their virulence. The aim of the current study was to determine responses in terms of interleukin (IL)-1beta, IL-6, IL-8 and IL-10 secretion induced by Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Streptococcus gordonii in order to gauge their virulence potential. HGECs were challenged with the four bacterial species, live or heat killed, at various multiplicity of infections and the elicited IL-1beta, IL-6, IL-8 and IL-10 responses were assayed by enzyme-linked immunosorbent assay. Primary HGECs challenged with live P. gingivalis produced high levels of IL-1beta, while challenge with live A. actinomycetemcomitans gave high levels of IL-8. The opportunistic pathogen F. nucleatum induces the highest levels of pro-inflammatory cytokines, while the commensal S. gordonii is the least stimulatory. We conclude that various dental plaque biofilm bacteria induce different cytokine response profiles in primary HGECs that may reflect their individual virulence or commensal status.

Modification of Salmonella Lipopolysaccharides Prevents the Outer Membrane Penetration of Novobiocin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nobre, Thatyane M.; Martynowycz, Michael W.; Andreev, Konstantin

Small hydrophilic antibiotics traverse the outer membrane of Gram-negative bacteria through porin channels. Large lipophilic agents traverse the outer membrane through its bilayer, containing a majority of lipopolysaccharides in its outer leaflet. Genes controlled by the two-component regulatory system PhoPQ modify lipopolysaccharides. We isolate lipopolysaccharides from isogenic mutants of Salmonella sp., one lacking the modification, the other fully modified. These lipopolysaccharides were reconstituted asmonolayers at the air-water interface, and their properties, aswell as their interaction with a large lipophilic drug, novobiocin, was studied. X-ray reflectivity showed that the drug penetrated the monolayer of the unmodified lipopolysaccharides reaching the hydrophobic region,butwasmore » prevented fromthis penetration intothemodified lipopolysaccharides.Results correlatewith behavior of bacterial cells, which become resistant to antibiotics after PhoPQ-regulated modifications. Grazing incidence x-ray diffraction showed that novobiocin produced a striking increase in crystalline coherence length, and the size of the near-crystalline domains.« less

Attenuation of methamphetamine-induced nigrostriatal dopaminergic neurotoxicity in mice by lipopolysaccharide pretreatment.

PubMed

Lin, Yin Chiu; Kuo, Yu-Min; Liao, Pao-Chi; Cherng, Chianfang G; Su, Su-Wen; Yu, Lung

2007-04-30

Immunological activation has been proposed to play a role in methamphetamine-induced dopaminergic terminal damage. In this study, we examined the roles of lipopolysaccharide, a pro-inflammatory and inflammatory factor, treatment in modulating the methamphetamine-induced nigrostriatal dopamine neurotoxicity. Lipopolysaccharide pretreatment did not affect the basal body temperature or methamphetamine-elicited hyperthermia three days later. Such systemic lipopolysaccharide treatment mitigated methamphetamine-induced striatal dopamine and 3,4-dihydroxyphenylacetic acid depletions in a dose-dependent manner. As the most potent dose (1 mg/kg) of lipopolysaccharide was administered two weeks, one day before or after the methamphetamine dosing regimen, methamphetamine-induced striatal dopamine and 3,4-dihydroxyphenylacetic acid depletions remained unaltered. Moreover, systemic lipopolysaccharide pretreatment (1 mg/kg) attenuated local methamphetamine infusion-produced dopamine and 3,4-dihydroxyphenylacetic acid depletions in the striatum, indicating that the protective effect of lipopolysaccharide is less likely due to interrupted peripheral distribution or metabolism of methamphetamine. We concluded a critical time window for systemic lipopolysaccharide pretreatment in exerting effective protection against methamphetamine-induced nigrostriatal dopamine neurotoxicity.

Integration of non-oral bacteria into in vitro oral biofilms.

PubMed

Thurnheer, Thomas; Belibasakis, Georgios N

2015-01-01

Biofilms are polymicrobial communities that grow on surfaces in nature. Oral bacteria can spontaneously form biofilms on the surface of teeth, which may compromise the health of the teeth, or their surrounding (periodontal) tissues. While the oral bacteria exhibit high tropism for their specialized ecological niche, it is not clear if bacteria that are not part of the normal oral microbiota can efficiently colonize and grow within oral biofilms. By using an in vitro "supragingival" biofilm model of 6 oral species, this study aimed to investigate if 3 individual bacterial species that are not part of the normal oral microbiota (Eschericia coli, Staphylococcus aureus, Enterococcus faecails) and one not previously tested oral species (Aggregatibacter actinomycetemcomitans) can be incorporated into this established supragingival biofilm model. Staphylococcus aureus and A. actinomycetemcomitans were able to grow efficiently in the biofilm, without disrupting the growth of the remaining species. They localized in sparse small aggregates within the biofilm mass. Enterococcus faecalis and E. coli were both able to populate the biofilm at high numbers, and suppressed the growth of A. oris and S. mutants. Enterococcus faecalis was arranged in a chain-like conformation, whereas E. coli was densely and evenly spread throughout the biofilm mass. In conclusion, it is possible for selected species that are not part of the normal oral microbiota to be introduced into an oral biofilm, under the given experimental micro-environmental conditions. Moreover, the equilibrated incorporation of A. actinomycetemcomitans and S. aureus in this oral biofilm model could be a useful tool in the study of aggressive periodontitis and peri-implantitis, in which these organisms are involved, respectively.

Regulation of matrix metalloproteinase secretion by green tea catechins in a three-dimensional co-culture model of macrophages and gingival fibroblasts.

PubMed

Morin, Marie-Pierre; Grenier, Daniel

2017-03-01

Elevated levels of matrix metalloproteinases (MMPs) have been associated with the active phases of tissue and bone destruction in periodontitis, an inflammatory disease characterized by a significant breakdown of tooth support. In the present study, we used a three-dimensional (3D) co-culture model of macrophages and gingival fibroblasts to investigate the ability of a green tea extract and its major constituent epigallocatechin-3-gallate (EGCG) to regulate the secretion of MMP-3, -8, and -9. The 3D co-culture model was composed of gingival fibroblasts embedded in a type I collagen matrix overlaid with macrophages. Two arbitrary ratios were tested. The ratio composed of 1 macrophage to 10 fibroblasts was used to mimic a slightly inflamed periodontal site while the ratio composed of 10 macrophages to 1 fibroblast was used to mimic a severely inflamed periodontal site. The 3D co-culture model was pre-treated for 2h with either the green tea extract or EGCG. It was then stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS). The model was also first stimulated with LPS for 2h and then incubated with the green tea extract or EGCG. The concentrations of secreted MMP-3, -8, and -9 were quantified by enzyme-linked immunoassays. When the 3D co-culture model was stimulated with A. actinomycetemcomitans LPS, the 10:1 ratio of macrophages to gingival fibroblasts was associated with a highest secretion of MMP-3 and -9 and, to a lesser extent, MMP-8, than the 1:10 ratio. Non-cytotoxic concentrations of the green tea extract or EGCG reduced the basal secretion levels of all three MMPs. A 2-h treatment with the green tea extract or EGCG prior to the stimulation with LPS resulted in a dose-dependent decrease in MMP secretion, with MMP-9 showing the most significant decrease. A decrease in MMP secretion was also observed when the green tea extract or EGCG was added following a 2-h stimulation with LPS. Our results suggested that green tea catechins, and more

Enhanced antimicrobial activities of silver-nanoparticle-decorated reduced graphene nanocomposites against oral pathogens.

PubMed

Peng, Jian-Min; Lin, Jia-Cheng; Chen, Zhuo-Yu; Wei, Meng-Chao; Fu, Yuan-Xiang; Lu, Shu-Shen; Yu, Dong-Sheng; Zhao, Wei

2017-02-01

As a means of capitalizing on the synergistic properties between reduced graphene nanosheets (R-GNs) and silver nanoparticles (AgNPs), an efficient and convenient chemical reduction method was used to prepare silver-nanoparticle-decorated reduced graphene nanocomposites (R-GNs/Ag). The products were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman spectroscopy, which confirmed the loading of well-dispersed silver nanoparticles on reduced graphene sheets. Their antimicrobial activities against oral pathogens such as Candida albicans, Lactobacillus acidophilus, Streptococcus mutans, and Aggregatibacter actinomycetemcomitans were investigated by MIC determination, the counting of colony-forming units (CFU), agar diffusion tests, and growth curve observation. Compared with pure R-GNs and AgNPs, R-GNs/Ag composites exhibited enhanced antimicrobial properties owing to highly dispersed AgNPs on R-GNs. Copyright © 2016 Elsevier B.V. All rights reserved.

Subgingival Microbiota in White Patients With Desquamative Gingivitis: A Cross-Sectional Study.

PubMed

Arduino, Paolo G; Romano, Federica; Sasia, Danilo; Broccoletti, Roberto; Ricceri, Fulvio; Barbui, Anna Maria; Brossa, Silvia; Cipriani, Raffaella; Cricenti, Luca; Cabras, Marco; Aimetti, Mario

2017-07-01

Presence of epithelial desquamation, erythema, and erosions on gingival tissue is usually described in the literature as desquamative gingivitis (DG). A wide range of autoimmune/dermatologic disorders can manifest as DG, although the two more common are oral lichen planus and mucous membrane pemphigoid. The aim of this study is to investigate prevalence of 11 periodontopathogenic microorganisms in patients with DG and to compare it with the microbiologic status of individuals affected by plaque-induced gingivitis (pGI). Cross-sectional clinical and microbiologic data were obtained from 66 patients (33 in each group). Subgingival plaque samples were analyzed using semiquantitative polymerase chain reaction analysis. Statistically significant difference, but with little clinical significance, was observed in gingival conditions between the two groups, probably due to the worse home control hygiene of patients with DG. Prevalence and levels of Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum/periodonticum were statistically higher in samples from patients with DG than in those with pGI. In multivariate regression models, subgingival colonization of A. actinomycetemcomitans and F. nucleatum/periodonticum was not statistically associated with DG, whereas, high levels of E. corrodens were associated with 13-fold increased odds for DG. Microbiologic differences were found in subgingival plaque for patients with DG and pGI. This may suggest possible association between periodontal pathogens and DG.

Prediagnostic plasma antibody levels to periodontopathic bacteria and risk of coronary heart disease.

PubMed

Ueno, Masayuki; Izumi, Yuichi; Kawaguchi, Yoko; Ikeda, Ai; Iso, Hiroyasu; Inoue, Manami; Tsugane, Shoichiro

2012-01-01

Many epidemiological studies have indicated that periodontitis is an important risk factor for coronary heart disease (CHD). We examined whether plasma antibody levels to 3 major periodontal pathogens, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia predicted the risk of CHD events. A nested case-control research design (case: n = 191, control: n = 382), by matching gender, age, study area, date of blood collection, and time since last meal at blood collection, was employed in a large cohort of Japanese community residents.Antibody levels of periodontopathic bacteria were associated with risk of CHD after adjusting for BMI, smoking status, alcohol intake, history of hypertension, history of diabetes mellitus, exercise during leisure time, and perceived mental stress. The association was different by age subgroup. For subjects aged 40-55 years, the medium (31.7-184.9 U/mL) or high tertile plasma antibody level (> 184.9 U/mL) of A. actinomycetemcomitans showed higher risk of CHD (medium: OR = 3.72; 95% CI = 1.20-11.56, high: OR = 4.64; 95% CI = 1.52-14.18) than the low tertile level (< 31.7 U/mL). The ORs of CHD incidence became higher with an increase in IgG level of A. actinomycetemcomitans (P for trend = 0.007). For subjects aged 56-69 years, the high tertile level (> 414.1 U/mL) of P. intermedia was associated with higher risk of CHD (OR = 2.65; 95% CI = 1.18-5.94) in a dose-response fashion (P for trend = 0.007). The possible role of periodontopathic bacteria as a risk factor for CHD incidence was suggested by the results of this study by the elevated antibody level to these bacteria with the increased risk of CHD.

Response to antiseptic agents of periodontal pathogens in in vitro biofilms on titanium and zirconium surfaces.

PubMed

Sánchez, M C; Fernández, E; Llama-Palacios, A; Figuero, E; Herrera, D; Sanz, M

2017-04-01

The aim of this study was to develop in vitro biofilms on SLA titanium (Ti-SLA) and zirconium oxide (ZrO 2 ) surfaces and to evaluate the effect of antiseptic agents on the number of putative periodontal pathogenic species. An in vitro biofilm model was developed on sterile discs of Ti-SLA and ZrO 2 . Three antiseptic agents [chlorhexidine and cetyl-pyridinium-chloride (CHX/CPC), essential oils (EEOOs) and cetyl-peridinium-chloride (CPC)] were applied to 72-h biofilms, immersing discs during 1min in the antiseptic solution, either with or without mechanical disruption. Viable bacteria [colony forming units (CFU/mL)] were measured by quantitative polymerase chain reaction (qPCR) combined with propidium monoazide. A generalized lineal model was constructed to determine the effect of the agents on the viable bacterial counts of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Fusobacterium nucleatum on each surface. The exposure to each antiseptic solution resulted in a statistically significant reductions in the number of viable target species included in the in vitro multi-species biofilm, on both Ti-SLA and ZrO 2 (p<0.001) which was of up to 2 orders for A. actinomycetemcomitans, for P. gingivalis 2 orders on Ti-SLA and up to 3 orders on ZrO 2, and, for F. nucleatum up to 4 orders. No significant differences were found in counts of the tested bacteria between in vitro biofilms formed on both Ti-SLA and ZrO 2 , after topically exposure to the antimicrobial agents whether the application was purely chemical or combined with mechanical disruption. A. actinomycetemcomitans, P. gingivalis and F. nucleatum responded similarly to their exposure to antiseptics when grown in multispecies biofilms on titanium and zirconium surfaces, in spite of the described structural differences between these bacterial communities. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Regulation of adrenomedullin and nitric oxide production by periodontal bacteria.

PubMed

Hussain, Q A; McKay, I J; Gonzales-Marin, C; Allaker, R P

2015-10-01

In periodontitis the host response to bacterial challenge includes activity of the multifunctional molecules adrenomedullin (AM) and nitric oxide (NO). The aim of this study was to investigate the role of periodontal bacteria in regulating the production of these molecules from cultured cells. Regulation of AM and NO production from oral keratinocytes when challenged with culture supernatants from Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Veillonella atypica, Streptococcus salivarius and Candida albicans was examined. AM and NO were measured in cell culture supernatants using an enzyme-linked immunosorbent assay and the nitrate/nitrite (NO metabolites) Griess assay respectively. Cellular production of AM and inducible NO synthase was also analysed in target cells by immunofluorescence and Western blot analysis. The inter-relationship of AM and NO production were further investigated with macrophages. A. actinomycetemcomitans and C. rectus induced maximal levels of both AM and NO after 6 and 48 h respectively from oral keratinocytes. AM production in macrophages was upregulated in response to the NO donor S-nitrosoglutathione and partially blocked by the inducible NO synthase inhibitor, N(ω) -Nitro-l-arginine methyl ester hydrochloride. Likewise, NO production was increased upon exposure to AM, while the AM receptor antagonist AM 22-52 reduced the release of NO. Pathogens associated with aggressive periodontitis, A. actinomycetemcomitans and C. rectus, were more effective than those associated with chronic periodontitis, P. gingivalis and Prev. intermedia, and commensals, S. salivarius and V. atypica, as regards the upregulation of AM and NO production from oral keratinocytes. Interaction between these molecules was also demonstrated with macrophages. Understanding the coordinated regulation of AM and NO production in response to periodontal bacteria may identify

Antimicrobial peptides and nitric oxide production by neutrophils from periodontitis subjects

PubMed Central

Mariano, F.S.; Campanelli, A.P.; Nociti, F.H.; Mattos-Graner, R.O.; Gonçalves, R.B.

2012-01-01

Neutrophils play an important role in periodontitis by producing nitric oxide (NO) and antimicrobial peptides, molecules with microbicidal activity via oxygen-dependent and -independent mechanisms, respectively. It is unknown whether variation in the production of antimicrobial peptides such as LL-37, human neutrophil peptides (HNP) 1-3, and NO by neutrophils influences the pathogenesis of periodontal diseases. We compared the production of these peptides and NO by lipopolysaccharide (LPS)-stimulated neutrophils isolated from healthy subjects and from patients with periodontitis. Peripheral blood neutrophils were cultured with or without Aggregatibacter actinomycetemcomitans-LPS (Aa-LPS), Porphyromonas gingivalis-LPS (Pg-LPS) and Escherichia coli-LPS (Ec-LPS). qRT-PCR was used to determine quantities of HNP 1-3 and LL-37 mRNA in neutrophils. Amounts of HNP 1-3 and LL-37 proteins in the cell culture supernatants were also determined by ELISA. In addition, NO levels in neutrophil culture supernatants were quantitated by the Griess reaction. Neutrophils from periodontitis patients cultured with Aa-LPS, Pg-LPS and Ec-LPS expressed higher HNP 1-3 mRNA than neutrophils from healthy subjects. LL-37 mRNA expression was higher in neutrophils from patients stimulated with Aa-LPS. Neutrophils from periodontitis patients produced significantly higher LL-37 protein levels than neutrophils from healthy subjects when stimulated with Pg-LPS and Ec-LPS, but no difference was observed in HNP 1-3 production. Neutrophils from periodontitis patients cultured or not with Pg-LPS and Ec-LPS produced significantly lower NO levels than neutrophils from healthy subjects. The significant differences in the production of LL-37 and NO between neutrophils from healthy and periodontitis subjects indicate that production of these molecules might influence individual susceptibility to important periodontal pathogens. PMID:22850872

A novel approach to the use of subgingival controlled-release chlorhexidine delivery in chronic periodontitis: a randomized clinical trial.

PubMed

Gonzales, Jose R; Harnack, Lutz; Schmitt-Corsitto, Gabriella; Boedeker, Rolf H; Chakraborty, Trinad; Domann, Eugen; Meyle, Joerg

2011-08-01

We aimed to analyze clinical, microbiologic, and serologic effects of chlorhexidine (CHX) chips used as a subgingival controlled-release delivery device before and immediately after scaling and root planing (SRP). Twenty-four patients presenting with ≥12 teeth with probing depth (PD) ≥5 mm and bleeding on probing were assigned in test or control groups. After prophylaxis, CHX chips (test) or placebo chips (control) were placed in pockets with PD ≥5 mm. Ten days later, SRP was performed in all teeth with PD ≥4 mm in a single appointment. Immediately after SRP, new chips were inserted in all pockets with PD ≥5 mm. Parameters were assessed at baseline; beginning of SRP; and 1, 3, and 6 months after treatment. Subgingival samples were obtained at baseline; beginning of SRP; and at 1 month after treatment. Periodontal pathogens Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola were analyzed. Serum levels of high sensitive C-reactive and lipopolysaccharide-binding proteins were measured. The changes of the parameters between and within the groups were tested by Mann-Whitney U test (P <0.05). All clinical and serologic parameters improved in both groups over time. There was a significant difference in clinical attachment level (CAL) gain from baseline to 6 months between groups (1.17 mm in the test group versus 0.79 mm in the placebo group) (P <0.05). The treatment with CHX chips showed a greater reduction of the microorganisms of the "red complex" after 1 month (P = 0.02). The use of CHX chips before and immediately after SRP improved CAL and reduced the subgingival microorganisms of the red complex in the treatment of chronic periodontitis.

Critical Role of MKP-1 in Lipopolysaccharide-Induced Osteoclast Formation through CXCL1 and CXCL2

PubMed Central

Valerio, Michael S.; Herbert, Bethany A.; Basilakos, Dimitrios S.; Browne, Courtney; Yu, Hong; Kirkwood, Keith L.

2014-01-01

Osteoclast (OC) progenitors (OCP) have been defined in the bone marrow (BM) as CD3−CD45R(B220)−GR1−CD11blo/−CD115+ (dOCP) and more recently in the peripheral blood (PB) as Lym−Ly6G−CD11b+Ly6C+. These progenitors respond to stimuli, including LPS from periopathogenic Aggregatibacter actinomycetemcomitans, activating MAPK signaling, resulting in cytokine/chemokine-mediated osteoclastogenesis. Intracellular negative signaling pathways, including MAPK phosphatase-1 (MKP-1, gene Dusp1) deactivate MAPK pathways (p-p38 and p-JNK) and reduce inflammatory cytokines/chemokines. Objective To delineate the role of MKP-1 in chemokine-mediated OC formation using defined OC progenitor populations. Given its role in innate immune inflammatory signaling, we hypothesize that MKP-1 regulates LPS-induced OC formation from BM OCP through deregulated chemokines. Methods BM and PB from WT and Dusp1−/− female mice (8–12wks) was obtained and sorted into defined progenitor populations. BM sorted dOCP were primed with MCSF and RANKL (48hrs), blocked with vehicle or chemokine blocking antibodies and stimulated with LPS (48–96hrs). TRAP assay and OC activity were measured for OC formation and activity following treatments. Nanostring Array and qPCR were utilized for gene expression analysis. Results Dusp1−/− dOCPs formed more and larger osteoclasts from CD11bhi and dOCP compared to matched WT (P<0.05 each). PB-derived dOCP produced larger and more functional osteoclasts from Dusp1−/− mice compared to WT controls. Nanostring array data revealed significant deregulation in chemokine expression from Dusp1−/− vs. WT cells. qPCR validation of target genes revealed that Dusp1 deficient CD11b+ populations display 1.5–3.5-fold greater expression of CXCL1 and 2–3-fold greater expression of CXCL2 compared to WT in CD11bhi and dOCP (P<0.05 each). Antibody blocking studies using anti-CXCL1 and CXCL2 antibodies blunted osteoclastogenesis in Dusp1−/− cells. Conclusion

The presence of cariogenic and periodontal pathogens in the oral cavity of one-year-old infants delivered pre-term with very low birthweights: a case control study

PubMed Central

2014-01-01

Background Recently, the dental literature has focused mainly on the microbial colonization of healthy full-term infants and their mothers or caretakers. However, oral microbial acquisition by premature infants has not been adequately investigated, and the correlation between pre-term birth and the presence of cariogenic and periodontal pathogens has not been determined. The aim of this study was to identify the presence and quantities of representative cariogenic and periodontal pathogens in the oral cavities of 12-month-old infants and compare the occurrence of these microbes between a cohort of pre-term infants with very low birthweights and a control cohort comprising full-term infants. Methods The research cohort was composed of 69 one-year-old infants, of whom 24 were born prematurely with very low birthweights and 45 of whom were carried to full term. Information regarding the infants’ gestational age, mode of delivery, general health status, birthweight and antibiotic use were obtained from hospital records and through oral interviews. At 12 months of age, both groups of infants were examined, and unstimulated saliva samples from the dorsum of the tongue and dental plaque samples were collected. The microorganisms (Streptococcus mutans, Lactobacillus spp., Actinomyces spp., Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Peptostreptococcus micros, Prevotella intermedia, Fusobacterium nucleatum) were identified and their quantities were evaluated using a PCR-based method. The chi-squared and Fisher’s factorial tests were used for the statistical evaluations. Results The infants had a high prevalence of cariogenic microbes and of Fusosbacterium nucleatum and Aggregatibacter actinomycetemcomitans. Cariogenic microbes were detected in 91.7% of the very low birthweight infants and in all full-term infants. Periodontal pathogens were present in 83% of the pre-term infants and in 96% of the full

Fatty Acids Present in the Lipopolysaccharide of Rhizobium trifolii

PubMed Central

Russa, R.; Lorkiewicz, Z.

1974-01-01

Approximately 70% of the fatty acids recovered after acid or alkaline hydrolysis of the lipopolysaccharide of Rhizobium trifolii were hydroxy fatty acids identified as hydroxymyristic and hydroxypalmitic acids. Palmitic acid was the only saturated fatty acid found in the lipopolysaccharide of R. trifolii. Octadecenoic and a small amount of hexadecenoic acids were also identified. The results of BF3 methanolysis and hydroxylaminolysis suggest that hydroxypalmitic acid is N-acyl bound. PMID:4852028

SIRT2 ameliorates lipopolysaccharide-induced inflammation in macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Ae Sin; Jung, Yu Jin; Kim, Dal

2014-08-08

Highlights: • Knockout of SIRT2 attenuates lipopolysaccharide-induced iNOS expression. • Lipopolysaccharide-induced NO production is decreased in SIRT2 KO macrophage. • SIRT2 deficiency suppresses lipopolysaccharide-induced ROS production in macrophage. • M1-macrophage related factors are decreased in SIRT2 deficient cells. • SIRT2 deficiency decreases lipopolysaccharide-induced activation of NFκB. - Abstract: Introduction: SIRT2 is a NAD(+)-dependent deacetylases and associated with numerous processes such as infection, carcinogenesis, DNA damage and cell cycle regulation. However, the role of SIRT2 in inflammatory process in macrophage remains unclear. Materials and methods: In the present study, we have evaluated the regulatory effects of SIRT2 in lipopolysaccharide (LPS)-stimulated macrophagesmore » isolated from SIRT2 knockout (KO) and wild type (WT) mice or Raw264.7 macrophage cells. As inflammatory parameters, expression of inducible nitric oxide synthase (iNOS), the productions of nitric oxide, reactive oxygen species (ROS) and M1-macrophage-related factors were evaluated. We also examined the effects of SIRT2 on activation of nuclear factor-kappaB (NFκB) signaling. Results: SIRT2 deficiency inhibits LPS-induced iNOS mRNA and protein expression in bone marrow derived macrophages. SIRT2-siRNA transfection also suppressed LPS-induced iNOS expression in Raw264.7 macrophage cells. Bone marrow derived macrophages isolated from SIRT2 KO mice produced lower nitric oxide and expressed lower levels of M1-macrophage related markers including iNOS and CD86 in response to LPS than WT mice. Decrease of SIRT2 reduced the LPS-induced reactive oxygen species production. Deficiency of SIRT2 resulted in inhibition of NFκB activation through reducing the phosphorylation and degradation of IκBα. The phosphorylation and nuclear translocation of p65 was significantly decreased in SIRT2-deficient macrophages after LPS stimulation. Discussion: Our data suggested

Influence of feeding status on neuronal activity in the hypothalamus during lipopolysaccharide-induced anorexia in rats.

PubMed

Gautron, L; Mingam, R; Moranis, A; Combe, C; Layé, S

2005-01-01

Fasting attenuates disease-associated anorexia, but the mechanisms underlying this effect are not well understood. In the present study, we investigated the extent to which a 48 h fast alters hypothalamic neuronal activity in response to the anorectic effects of lipopolysaccharide in rats. Male rats were fed ad libitum or fasted, and were injected with i.p. saline or lipopolysaccharide (250 microg/kg). Immunohistochemistry for Fos protein was used to visualize neuronal activity in response to lipopolysaccharide within selected hypothalamic feeding regulatory nuclei. Additionally, food intake, body weight, plasma interleukin-1 and leptin levels, and the expression of mRNA for appetite-related neuropeptides (neuropeptide Y, proopiomelanocortin and cocaine-amphetamine-regulated transcript) were measured in a time-related manner. Our data show that the pattern of lipopolysaccharide-induced Fos expression was similar in most hypothalamic nuclei whatever the feeding status. However, we observed that fasting significantly reduced lipopolysaccharide-induced Fos expression in the paraventricular nucleus, in association with an attenuated lipopolysaccharide-induced anorexia and body weight loss. Moreover, lipopolysaccharide reduced fasting-induced Fos expression in the perifornical area of the lateral hypothalamus. Lipopolysaccharide-induced circulating levels of interleukin-1 were similar across feeding status. Finally, fasting, but not lipopolysaccharide, affected circulating level of leptin and appetite-related neuropeptides expression in the arcuate nucleus. Together, our data show that fasting modulates lipopolysaccharide-induced anorexia and body weight loss in association with neural changes in specific hypothalamic nuclei.

Structure and Function of Lipopolysaccharide Binding Protein

NASA Astrophysics Data System (ADS)

Schumann, Ralf R.; Leong, Steven R.; Flaggs, Gail W.; Gray, Patrick W.; Wright, Samuel D.; Mathison, John C.; Tobias, Peter S.; Ulevitch, Richard J.

1990-09-01

The primary structure of lipopolysaccharide binding protein (LBP), a trace plasma protein that binds to the lipid A moiety of bacterial lipopolysaccharides (LPSs), was deduced by sequencing cloned complementary DNA. LBP shares sequence identity with another LPS binding protein found in granulocytes, bactericidal/permeability-increasing protein, and with cholesterol ester transport protein of the plasma. LBP may control the response to LPS under physiologic conditions by forming high-affinity complexes with LPS that bind to monocytes and macrophages, which then secrete tumor necrosis factor. The identification of this pathway for LPS-induced monocyte stimulation may aid in the development of treatments for diseases in which Gram-negative sepsis or endotoxemia are involved.

Reactive oxygen species are involved in lipopolysaccharide-induced intrauterine growth restriction and skeletal development retardation in mice.

PubMed

Xu, De-Xiang; Chen, Yuan-Hua; Zhao, Lei; Wang, Hua; Wei, Wei

2006-12-01

Maternal infection is a cause of adverse developmental outcomes including embryonic resorption, intrauterine fetal death, and preterm labor. Lipopolysaccharide-induced developmental toxicity at early gestational stages has been well characterized. The purpose of the present study was to investigate the effects of maternal lipopolysaccharide exposure at late gestational stages on intrauterine fetal growth and skeletal development and to assess the potential role of reactive oxygen species in lipopolysaccharide-induced intrauterine fetal growth restriction and skeletal development retardation. The timed pregnant CD-1 mice were intraperitoneally injected with lipopolysaccharide (25 to 75 microg/kg per day) on gestational day 15 to 17. To investigate the role of reactive oxygen species on lipopolysaccharide-induced intrauterine fetal growth restriction and skeletal development retardation, the pregnant mice were injected with alpha-phenyl-N-t-butylnitrone (100 mg/kg, intraperitoneally) at 30 minutes before lipopolysaccharide (75 microg/kg per day, intraperitoneally), followed by an additional dose of alpha-phenyl-N-t-butylnitrone (50 mg/kg, intraperitoneally) at 3 hours after lipopolysaccharide. The number of live fetuses, dead fetuses, and resorption sites was counted on gestational day 18. Live fetuses in each litter were weighed. Crown-rump and tail lengths were examined and skeletal development was evaluated. Maternal lipopolysaccharide exposure significantly increased fetal mortality, reduced fetal weight and crown-rump and tail lengths of live fetuses, and retarded skeletal ossification in caudal vertebrae, anterior and posterior phalanges, and supraoccipital bone in a dose-dependent manner. Alpha-phenyl-N-t-butylnitrone, a free radical spin-trapping agent, almost completely blocked lipopolysaccharide-induced fetal death (63.2% in lipopolysaccharide group versus 6.5% in alpha-phenyl-N-t-butylnitrone + lipopolysaccharide group, P < .01). In addition, alpha

Structural analysis and involvement in plant innate immunity of Xanthomonas axonopodis pv. citri lipopolysaccharide.

PubMed

Casabuono, Adriana; Petrocelli, Silvana; Ottado, Jorgelina; Orellano, Elena G; Couto, Alicia S

2011-07-22

Xanthomonas axonopodis pv. citri (Xac) causes citrus canker, provoking defoliation and premature fruit drop with concomitant economical damage. In plant pathogenic bacteria, lipopolysaccharides are important virulence factors, and they are being increasingly recognized as major pathogen-associated molecular patterns for plants. In general, three domains are recognized in a lipopolysaccharide: the hydrophobic lipid A, the hydrophilic O-antigen polysaccharide, and the core oligosaccharide, connecting lipid A and O-antigen. In this work, we have determined the structure of purified lipopolysaccharides obtained from Xanthomonas axonopodis pv. citri wild type and a mutant of the O-antigen ABC transporter encoded by the wzt gene. High pH anion exchange chromatography and matrix-assisted laser desorption/ionization mass spectrum analysis were performed, enabling determination of the structure not only of the released oligosaccharides and lipid A moieties but also the intact lipopolysaccharides. The results demonstrate that Xac wild type and Xacwzt LPSs are composed mainly of a penta- or tetra-acylated diglucosamine backbone attached to either two pyrophosphorylethanolamine groups or to one pyrophosphorylethanolamine group and one phosphorylethanolamine group. The core region consists of a branched oligosaccharide formed by Kdo₂Hex₆GalA₃Fuc3NAcRha₄ and two phosphate groups. As expected, the presence of a rhamnose homo-oligosaccharide as O-antigen was determined only in the Xac wild type lipopolysaccharide. In addition, we have examined how lipopolysaccharides from Xac function in the pathogenesis process. We analyzed the response of the different lipopolysaccharides during the stomata aperture closure cycle, the callose deposition, the expression of defense-related genes, and reactive oxygen species production in citrus leaves, suggesting a functional role of the O-antigen from Xac lipopolysaccharides in the basal response.

Structural and functional insights into the lipopolysaccharide ABC transporter LptB2FG.

PubMed

Dong, Haohao; Zhang, Zhengyu; Tang, Xiaodi; Paterson, Neil G; Dong, Changjiang

2017-08-09

The cell surface of most Gram-negative bacteria contains lipopolysaccharide that is essential for their viability and drug resistance. A 134-kDa protein complex LptB 2 FG is unique among ATP-binding cassette transporters because it extracts lipopolysaccharide from the external leaflet of the inner membrane and propels it along a filament that extends across the periplasm to directly deliver lipopolysaccharide into the external leaflet of the outer membrane. Here we report the crystal structure of the lipopolysaccharide transporter LptB 2 FG from Klebsiella pneumoniae, in which both LptF and LptG are composed of a β-jellyroll-like periplasmic domain and six α-helical segments in the transmembrane domain. LptF and LptG form a central cavity containing highly conserved hydrophobic residues. Structural and functional studies suggest that LptB 2 FG uses an alternating lateral access mechanism to extract lipopolysaccharide and traffic it along the hydrophobic cavity toward the transporter's periplasmic domains.Lipopolysaccharides (LPS) are synthesized at the periplasmic side of the inner membrane of Gram-negative bacteria and are then extracted by the LptB 2 FG complex during the first step of LPS transport to the outer membrane. Here the authors present the LptB 2 FG structure, which supports an alternating lateral access mechanism for LPS extraction.

Structure, viability and bacterial kinetics of an in vitro biofilm model using six bacteria from the subgingival microbiota.

PubMed

Sánchez, M C; Llama-Palacios, A; Blanc, V; León, R; Herrera, D; Sanz, M

2011-04-01

There are few in vitro models available in the scientific literature for study of the structure, formation and development of the subgingival biofilm. The purpose of this study was to develop and validate an in vitro biofilm model, using representative selected bacteria from the subgingival microbiota. Six standard reference strains were used to develop biofilms over sterile ceramic calcium hydroxyapatite discs coated with saliva within the wells of presterilized polystyrene tissue culture plates. The selected species represent initial (Streptococcus oralis and Actinomyces naeslundii), early (Veillonella parvula), secondary (Fusobacterium nucleatum) and late colonizers (Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). The structure of the biofilm obtained was studied using a vital fluorescence technique in conjunction with confocal laser scanning microscopy. The biofilm bacterial kinetics were studied by terminal restriction fragment length polymorphism analysis. After 12 h, initial and early colonizers were the first microorganisms detected adhering to the calcium hydroxyapatite discs. The intermediate colonizer F. nucleatum was not detected in the model until 24 h of incubation. Late colonizers A. actinomycetemcomitans and P. gingivalis could be measured inside the biofilm after 48 h. The biofilm reached its steady state between 72 and 96 h after inoculation, with bacterial vitality increasing from the hydroxyapatite surface to the central part of the biofilm. An in vitro biofilm model was developed and validated, demonstrating a pattern of bacterial colonization and maturation similar to the in vivo development of the subgingival biofilm. © 2011 John Wiley & Sons A/S.

Clinical and microbiological parameters in patients with self-ligating and conventional brackets during early phase of orthodontic treatment.

PubMed

Pejda, Slavica; Varga, Marina Lapter; Milosevic, Sandra Anic; Mestrovic, Senka; Slaj, Martina; Repic, Dario; Bosnjak, Andrija

2013-01-01

To determine the effect of different bracket designs (conventional brackets and self-ligating brackets) on periodontal clinical parameters and periodontal pathogens in subgingival plaque. The following inclusion criteria were used: requirement of orthodontic treatment plan starting with alignment and leveling, good general health, healthy periodontium, no antibiotic therapy in the previous 6 months before the beginning of the study, and no smoking. The study sample totaled 38 patients (13 male, 25 female; mean age, 14.6 ± 2.0 years). Patients were divided into two groups with random distribution of brackets. Recording of clinical parameters was done before the placement of the orthodontic appliance (T0) and at 6 weeks (T1), 12 weeks (T2), and 18 weeks (T3) after full bonding of orthodontic appliances. Periodontal pathogens of subgingival microflora were detected at T3 using a commercially available polymerase chain reaction test (micro-Dent test) that contains probes for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia, and Treponema denticola. There was a statistically significant higher prevalence of A actinomycetemcomitans in patients with conventional brackets than in patients with self-ligating brackets, but there was no statistically significant difference for other putative periodontal pathogens. The two different types of brackets did not show statistically significant differences in periodontal clinical parameters. Bracket design does not seem to have a strong influence on periodontal clinical parameters and periodontal pathogens in subgingival plaque. The correlation between some periodontal pathogens and clinical periodontal parameters was weak.

Killing activity of LFchimera on periodontopathic bacteria and multispecies oral biofilm formation in vitro.

PubMed

Ruangcharoen, Sopita; Suwannarong, Waraporn; Lachica, Marie Rossini Carmela T; Bolscher, Jan G M; Nazmi, Kamran; Khunkitti, Watcharee; Taweechaisupapong, Suwimol

2017-08-19

Lactoferrin chimera (LFchimera), a heterodimeric peptide containing lactoferrampin (LFampin265-284) and a part of lactoferricin (LFcin17-30), possesses a broad spectrum of antimicrobial activity. However, there is no report on the inhibitory effects of LFchimera against multispecies oral biofilms. This study aimed to determine the effects of LFchimera in comparison to chlorhexidine digluconate (CHX) and minocycline hydrochloride (MH), on in vitro multispecies biofilms derived from subgingival plaque of periodontitis patients harboring Aggregatibacter actinomycetemcomitans. First the effects of LFchimera against planktonic and an 1-day old biofilm of the periodontopathic bacteria, A. actinomycetemcomitans ATCC 43718 were established. Then, the effects on biofilm formation and bacterial viability in the multispecies biofilm were determined by crystal violet staining and LIVE/DEAD BacLight Bacterial Viability kit, respectively. The results revealed that a significant reduction (P < 0.05) in biofilm formation occurred after 15 min exposure to 20 µM of LFchimera or CHX compared to control. In contrast, MH at concentration up to 100 µM did not inhibit biofilm formation. The ratio of live/dead bacteria in biofilm was also significantly lower after 15 min exposure to 20 µM of LFchimera compared to control and 20-50 µM of CHX and MH. Altogether, the results obtained indicate that LFchimera is able to inhibit in vitro subgingival biofilm formation and reduce viability of multispecies bacteria in biofilm better than CHX and MH.

Oral and endotracheal tubes colonization by periodontal bacteria: a case-control ICU study.

PubMed

Porto, A N; Cortelli, S C; Borges, A H; Matos, F Z; Aquino, D R; Miranda, T B; Oliveira Costa, F; Aranha, A F; Cortelli, J R

2016-03-01

Periodontal infection is a possible risk factor for respiratory disorders; however, no studies have assessed the colonization of periodontal pathogens in endotracheal tubes (ET). This case-control study analyzed whether periodontal pathogens are able to colonize ET of dentate and edentulous patients in intensive care units (ICU) and whether oral and ET periodontal pathogen profiles have any correlation between these patients. We selected 18 dentate and 18 edentulous patients from 78 eligible ICU patients. Oral clinical examination including probing depth, clinical attachment level, gingival index , and plaque index was performed by a single examiner, followed by oral and ET sampling and processing by quantitative polymerase chain reaction (total bacterial load, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia). Data were statistically analyzed by Mann-Whitney U, two-way analysis of variance (p < 0.05). Among dentate, there was no correlation between clinical parameters and ET bacterial levels. Both dentate and edentulous patients showed similar ET bacterial levels. Dentate patients showed no correlation between oral and ET bacterial levels, while edentulous patients showed positive correlations between oral and ET levels of A. actinomycetemcomitans, P. gingivalis, and T. forsythia. Periodontal pathogens can colonize ET and the oral cavity of ICU patients. Periodontal pathogen profiles tend to be similar between dentate and edentulous ICU patients. In ICU patients, oral cavity represents a source of ET contamination. Although accompanied by higher oral bacterial levels, teeth do not seem to influence ET bacterial profiles.

Effect of teenage smoking on the prevalence of periodontal bacteria.

PubMed

Heikkinen, Anna Maria; Pitkäniemi, Janne; Kari, Kirsti; Pajukanta, Riitta; Elonheimo, Outi; Koskenvuo, Markku; Meurman, Jukka H

2012-04-01

The aim of our study was to investigate how teenage smoking affects the prevalence of periodontal bacteria and periodontal health with the hypothesis that smoking increases the prevalence of the bacteria. Oral health of 264 adolescents (15- to 16-year-olds) was clinically examined, and their smoking history was recorded. The participants also filled in a structured questionnaire recording their general health and health habits. Pooled subgingival plaque samples were taken for polymerase chain reaction analysis of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Prevotella nigrescens, and Treponema denticola. The prevalence of P. intermedia (21% vs. 4%, p = 0.01) and T. forsythia and T. denticola (23% vs. 8%, p < 0.05, for both) was higher among female smokers than among non-smokers. T. forsythia and T. denticola were more often associated with bleeding on probing (29% vs. 12%; 25% vs. 10%, respectively) and deep pockets (25% vs. 15%; 23% vs. 10%, respectively) with smokers than non-smokers. Among the girls, a significant association was found between pack-years and the prevalence of P. nigrescens (p < 0.007). In both genders, A. actinomycetemcomitans and P. gingivalis were rare in this study. To conclude, periodontal bacteria were associated with higher periodontal index scores among all teenage smokers. Smoking girls harbored more frequently certain periodontal bacteria than non-smokers, but this was not seen in boys. Hence, our study hypothesis was only partly confirmed.

Deoxyribonucleic Acid Probes Analyses for the Detection of Periodontal Pathogens.

PubMed

Al Yahfoufi, Zoubeida; Hadchiti, Wahib; Berberi, Antoine

2015-09-01

In clinical microbiology several techniques have been used to identify bacteria. Recently, Deoxyribonucleic acid (DNA)-based techniques have been introduced to detect human microbial pathogens in periodontal diseases. Deoxyribonucleic acid probes can detect bacteria at a very low level if we compared with the culture methods. These probes have shown rapid and cost-effective microbial diagnosis, good sensitivity and specificity for some periodontal pathogens in cases of severe periodontitis. Eighty-five patients were recruited for the study. Twenty-one subjects ranging between 22 and 48 years of age fulfilled the inclusion and exclusion criteria. Seventy-eight samples became available for DNA probe analysis from the deepest pockets in each quadrant. All 21 patients showed positive results for Prevotella intermedia; also, Prevotella gingivalis was identified in 19 subjects, Aggregatibacter actinomycetemcomitans in 6 subjects. P. intermedia was diagnosed positive in 82% of the subgingival samples taken, 79% for P. gingivalis, and 23% for A. actinomycetemcomitans. This study shows a high frequency of putative periodontal pathogens by using DNA probe technology, which is semi-quantitative in this study. Deoxyribonucleic acid probes can detect bacteria at very low level about 10(3) which is below the detection level of culture methods. The detection threshold of cultural methods. The three types of bacteria can be detected rapidly with high sensitivity by using the DNA probe by general practitioners, and thus can help in the diagnosis process and the treatment.

Structural Analysis and Involvement in Plant Innate Immunity of Xanthomonas axonopodis pv. citri Lipopolysaccharide*

PubMed Central

Casabuono, Adriana; Petrocelli, Silvana; Ottado, Jorgelina; Orellano, Elena G.; Couto, Alicia S.

2011-01-01

Xanthomonas axonopodis pv. citri (Xac) causes citrus canker, provoking defoliation and premature fruit drop with concomitant economical damage. In plant pathogenic bacteria, lipopolysaccharides are important virulence factors, and they are being increasingly recognized as major pathogen-associated molecular patterns for plants. In general, three domains are recognized in a lipopolysaccharide: the hydrophobic lipid A, the hydrophilic O-antigen polysaccharide, and the core oligosaccharide, connecting lipid A and O-antigen. In this work, we have determined the structure of purified lipopolysaccharides obtained from Xanthomonas axonopodis pv. citri wild type and a mutant of the O-antigen ABC transporter encoded by the wzt gene. High pH anion exchange chromatography and matrix-assisted laser desorption/ionization mass spectrum analysis were performed, enabling determination of the structure not only of the released oligosaccharides and lipid A moieties but also the intact lipopolysaccharides. The results demonstrate that Xac wild type and Xacwzt LPSs are composed mainly of a penta- or tetra-acylated diglucosamine backbone attached to either two pyrophosphorylethanolamine groups or to one pyrophosphorylethanolamine group and one phosphorylethanolamine group. The core region consists of a branched oligosaccharide formed by Kdo2Hex6GalA3Fuc3NAcRha4 and two phosphate groups. As expected, the presence of a rhamnose homo-oligosaccharide as O-antigen was determined only in the Xac wild type lipopolysaccharide. In addition, we have examined how lipopolysaccharides from Xac function in the pathogenesis process. We analyzed the response of the different lipopolysaccharides during the stomata aperture closure cycle, the callose deposition, the expression of defense-related genes, and reactive oxygen species production in citrus leaves, suggesting a functional role of the O-antigen from Xac lipopolysaccharides in the basal response. PMID:21596742

Survey of Innate Immune Responses to Burkholderia pseudomallei in Human Blood Identifies a Central Role for Lipopolysaccharide

PubMed Central

Chantratita, Narisara; Tandhavanant, Sarunporn; Myers, Nicolle D.; Seal, Sudeshna; Arayawichanont, Arkhom; Kliangsa-ad, Aroonsri; Hittle, Lauren E.; Ernst, Robert K.; Emond, Mary J.; Wurfel, Mark M.; Day, Nicholas P. J.; Peacock, Sharon J.; West, T. Eoin

2013-01-01

B. pseudomallei is a gram-negative bacterium that causes the tropical infection melioidosis. In northeast Thailand, mortality from melioidosis approaches 40%. As exemplified by the lipopolysaccharide-Toll-like receptor 4 interaction, innate immune responses to invading bacteria are precipitated by activation of host pathogen recognition receptors by pathogen associated molecular patterns. Human melioidosis is characterized by up-regulation of pathogen recognition receptors and pro-inflammatory cytokine release. In contrast to many gram-negative pathogens, however, the lipopolysaccharide of B. pseudomallei is considered only weakly inflammatory. We conducted a study in 300 healthy Thai subjects to investigate the ex vivo human blood response to various bacterial pathogen associated molecular patterns, including lipopolysaccharide from several bacteria, and to two heat-killed B. pseudomallei isolates. We measured cytokine levels after stimulation of fresh whole blood with a panel of stimuli. We found that age, sex, and white blood cell count modulate the innate immune response to B. pseudomallei. We further observed that, in comparison to other stimuli, the innate immune response to B. pseudomallei is most highly correlated with the response to lipopolysaccharide. The magnitude of cytokine responses induced by B. pseudomallei lipopolysaccharide was significantly greater than those induced by lipopolysaccharide from Escherichia coli and comparable to many responses induced by lipopolysaccharide from Salmonella minnesota despite lower amounts of lipid A in the B. pseudomallei lipopolysaccharide preparation. In human monocytes stimulated with B. pseudomallei, addition of polymyxin B or a TLR4/MD-2 neutralizing antibody inhibited the majority of TNF-α production. Challenging existing views, our data indicate that the innate immune response to B. pseudomallei in human blood is largely driven by lipopolysaccharide, and that the response to B. pseudomallei

Lipopolysaccharide and Aldoheptose Biosynthesis in Transketolase Mutants of Salmonella typhimurium

PubMed Central

Eidels, L.; Osborn, M. J.

1971-01-01

Genetic and biochemical evidence that sedoheptulose-7-phosphate is an obligatory precursor of the L-glycero-D-mannoheptose residues of the lipopolysaccharide of Salmonella was obtained by isolation and characterization of transketolase-negative mutants of Salmonella typhimurium. These mutants, which are defective in synthesis of sedoheptulose-7-phosphate, were found to produce an incomplete heptose-deficient lipopolysaccharide, and were also sensitive to bile salts, a characteristic property of heptose-deficient mutants. Phenotypic repair of the defect in lipopolysaccharide synthesis was obtained by addition of exogenous sedoheptulose-7-phosphate to growing cultures of the mutant strains. Characterization of revertants isolated either as transketolase-positive or heptose-positive provided further evidence that the heptose deficiency resulted from mutation at the transketolase locus. On the basis of these findings a possible pathway for conversion of sedoheptulose-7-phosphate to L-glycero-D-mannoheptose is proposed. PMID:4942911

DNA from Periodontopathogenic Bacteria Is Immunostimulatory for Mouse and Human Immune Cells

PubMed Central

Nonnenmacher, Claudia; Dalpke, Alexander; Zimmermann, Stefan; Flores-de-Jacoby, Lavin; Mutters, Reinier; Heeg, Klaus

2003-01-01

Although bacterial DNA (bDNA) containing unmethylated CpG motifs stimulates innate immune cells through Toll-like receptor 9 (TLR-9), its precise role in the pathophysiology of diseases is still equivocal. Here we examined the immunostimulatory effects of DNA extracted from periodontopathogenic bacteria. A major role in the etiology of periodontal diseases has been attributed to Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Peptostreptococcus micros. We therefore isolated DNA from these bacteria and stimulated murine macrophages and human gingival fibroblasts (HGF) in vitro. Furthermore, HEK 293 cells transfected with human TLR-9 were also stimulated with these DNA preparations. We observed that DNA from these pathogens stimulates macrophages and gingival fibroblasts to produce tumor necrosis factor alpha and interleukin-6 in a dose-dependent manner. Methylation of the CpG motifs abolished the observed effects. Activation of HEK 293 cells expressing TLR-9 which were responsive to bDNA but not to lipopolysaccharide confirmed that immunostimulation was achieved by bDNA. In addition, the examined bDNA differed in the ability to stimulate murine macrophages, HGF, and TLR-9-transfected cells. DNA from A. actinomycetemcomitans elicited a potent cytokine response, while DNA from P. gingivalis and P. micros showed lower immunostimulatory activity. Taken together, the results strongly suggest that DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros possesses immunostimulatory properties in regard to cytokine secretion by macrophages and fibroblasts. These stimulatory effects are due to unmethylated CpG motifs within bDNA and differ between distinct periodontopathogenic bacteria strains. Hence, immunostimulation by DNA from A. actinomycetemcomitans, P. gingivalis, and P. micros could contribute to the pathogenesis of periodontal diseases. PMID:12540566

Targeted Gene Silencing of Tumor Necrosis Factor Attenuates the Negative Inotropic Effects of Lipopolysaccharide in Isolated Contracting Cardiac Myocytes

PubMed Central

Ramabadran, R. S.; Chancey, Amanda; Vallejo, Jesus G.; Barger, Philip M.; Sivasubramanian, Natarajan; Mann, Douglas L.

2008-01-01

Bacterial endotoxin (lipopolysaccharide) depresses cardiovascular function; however, the mediators and signaling pathways that are responsible for the negative inotropic effects of lipopolysaccharide are not fully known. We used RNA interference to determine the relative role of tumor necrosis factor with respect to mediating the negative inotropic effects of lipopolysaccharide in isolated cardiac myocytes. Cardiac myocyte cultures were treated with lipopolysaccharide in the presence or absence of small interfering RNAs (siRNA) for tumor necrosis factor. We examined the effects of tumor necrosis factor siRNA on lipopolysaccharide-induced tumor necrosis factor messenger RNA (mRNA) and protein biosynthesis, as well as the negative inotropic effects of lipopolysaccharide in isolated contracting cardiac myocytes. Treatment of adult cardiac myocyte cultures with tumor necrosis factor siRNA significantly attenuated lipopolysaccharide-induced tumor necrosis factor mRNA and protein biosynthesis, whereas transfection with a double-stranded RNA that does not target mammalian mRNA had no effect. Pretreatment with tumor necrosis factor siRNA significantly attenuated, but did not abrogate, the lipopolysaccharide-induced decrease in sarcomere shortening in isolated contracting cardiac myocytes. In contrast, tumor necrosis factor siRNA had a comparatively smaller effect on improving sarcomere shortening once the negative inotropic effects of lipopolysaccharide were fully established. These results suggest that tumor necrosis factor plays an important upstream role in lipopolysaccharide-induced negative inotropic effects in isolated contracting cardiac myocytes and that other molecular mechanisms are responsible for the decrease in sarcomere shortening after sustained lipopolysaccharide signaling. PMID:18427645

Antibacterial activities of extracts from Ugandan medicinal plants used for oral care.

PubMed

Ocheng, Francis; Bwanga, Freddie; Joloba, Moses; Borg-Karlson, Ann-Karin; Gustafsson, Anders; Obua, Celestino

2014-08-08

Medicinal plants are widely used for treatment of oral/dental diseases in Uganda. To investigate antibacterial activities of 16 commonly used medicinal plants on microorganisms associated with periodontal diseases (PD) and dental caries (DC). Pulp juice and solvent extracts (hexane, methanol and water) from the plants were tested against Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia associated with PD and Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus associated with DC. Tests were done using agar well-diffusion (pulp juice) and agar-dilution (Solvent extracts) assays. Pulp juice from Zanthoxylum chalybeum and Euclea latidens showed activity against all the bacteria, Zanthoxylum chalybeum being most active. Hexane extract from aerial part of Helichrysum odoratissimum was most active (MIC: 0.125-0.5 mg/ml). Methanol extract from leaves of Lantana trifolia showed activity against all bacteria (MIC: 0.25-1 mg/ml). Several of the tested plants showed antibacterial activities against bacteria associated with PD and DC, meriting further investigations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Differentiation of oral bacteria in in vitro cultures and human saliva by secondary electrospray ionization - mass spectrometry

NASA Astrophysics Data System (ADS)

Bregy, Lukas; Müggler, Annick R.; Martinez-Lozano Sinues, Pablo; García-Gómez, Diego; Suter, Yannick; Belibasakis, Georgios N.; Kohler, Malcolm; Schmidlin, Patrick R.; Zenobi, Renato

2015-10-01

The detection of bacterial-specific volatile metabolites may be a valuable tool to predict infection. Here we applied a real-time mass spectrometric technique to investigate differences in volatile metabolic profiles of oral bacteria that cause periodontitis. We coupled a secondary electrospray ionization (SESI) source to a commercial high-resolution mass spectrometer to interrogate the headspace from bacterial cultures and human saliva. We identified 120 potential markers characteristic for periodontal pathogens Aggregatibacter actinomycetemcomitans (n = 13), Porphyromonas gingivalis (n = 70), Tanerella forsythia (n = 30) and Treponema denticola (n = 7) in in vitro cultures. In a second proof-of-principle phase, we found 18 (P. gingivalis, T. forsythia and T. denticola) of the 120 in vitro compounds in the saliva from a periodontitis patient with confirmed infection with P. gingivalis, T. forsythia and T. denticola with enhanced ion intensity compared to two healthy controls. In conclusion, this method has the ability to identify individual metabolites of microbial pathogens in a complex medium such as saliva.

Staphylococcus epidermidis Biofilms: Functional Molecules, Relation to Virulence, and Vaccine Potential

NASA Astrophysics Data System (ADS)

Mack, Dietrich; Davies, Angharad P.; Harris, Llinos G.; Knobloch, Johannes K. M.; Rohde, Holger

Medical device-associated infections, most frequently caused by Staphylococcus epidermidis and Staphylococcus aureus, are of increasing importance in modern medicine. The formation of adherent, multilayered bacterial biofilms is crucial in the pathogenesis of these infections. Polysaccharide intercellular adhesin (PIA), a homoglycan of β-1,6-linked 2-acetamido-2-deoxy-d-glucopyranosyl residues, of which about 15% are non-N-acetylated, is central to biofilm accumulation in staphylococci. It transpires that polysaccharides - structurally very similar to PIA - are also key to biofilm formation in a number of other organisms including the important human pathogens Escherichia coli, Aggregatibacter (Actinobacillus) actinomycetemcomitans, Yersinia pestis, and Bordetella spp. Apparently, synthesis of PIA and related polysaccharides is a general feature important for biofilm formation in diverse bacterial genera. Current knowledge about the structure and biosynthesis of PIA and related polysaccharides is reviewed. Additionally, information on their role in pathogenesis of biomaterial-related and other type of infections and the potential use of PIA and related compounds for prevention of infection is evaluated.

Periodontitis and myocardial hypertrophy.

PubMed

Suzuki, Jun-Ichi; Sato, Hiroki; Kaneko, Makoto; Yoshida, Asuka; Aoyama, Norio; Akimoto, Shouta; Wakayama, Kouji; Kumagai, Hidetoshi; Ikeda, Yuichi; Akazawa, Hiroshi; Izumi, Yuichi; Isobe, Mitsuaki; Komuro, Issei

2017-04-01

There is a deep relationship between cardiovascular disease and periodontitis. It has been reported that myocardial hypertrophy may be affected by periodontitis in clinical settings. Although these clinical observations had some study limitations, they strongly suggest a direct association between severity of periodontitis and left ventricular hypertrophy. However, the detailed mechanisms between myocardial hypertrophy and periodontitis have not yet been elucidated. Recently, we demonstrated that periodontal bacteria infection is closely related to myocardial hypertrophy. In murine transverse aortic constriction models, a periodontal pathogen, Aggregatibacter actinomycetemcomitans markedly enhanced cardiac hypertrophy with matrix metalloproteinase-2 activation, while another pathogen Porphyromonas gingivalis (P.g.) did not accelerate these pathological changes. In the isoproterenol-induced myocardial hypertrophy model, P.g. induced myocardial hypertrophy through Toll-like receptor-2 signaling. From our results and other reports, regulation of chronic inflammation induced by periodontitis may have a key role in the treatment of myocardial hypertrophy. In this article, we review the pathophysiological mechanism between myocardial hypertrophy and periodontitis.

Serum lipopolysaccharide-binding protein prediction of severe bacterial infection in cirrhotic patients with ascites.

PubMed

Albillos, Agustín; de-la-Hera, Antonio; Alvarez-Mon, Melchor

2004-05-15

Serum lipopolysaccharide-binding protein is increased in a subset of non-infected ascitic cirrhotic patients, a finding previously related to bacterial passage from the gut to the circulation without overt infection. We prospectively analysed the risk factors associated with a first episode of severe bacterial infection in 84 ascitic cirrhotics, followed up for a median of 46 weeks. The cumulative probability of such infection in patients with raised and normal lipopolysaccharide-binding protein was 32.4% and 8.0% (p=0.004), respectively. Increased lipopolysaccharide-binding protein was the only factor independently associated with severe bacterial infection in a multivariate analysis (relative risk 4.49, 95% CI 1.42-14.1). Monitoring of serum lipopolysaccharide-binding protein could, therefore, help to target cirrhotic patients with ascites for antibiotic prophylaxis.

Malva sylvestris Inhibits Inflammatory Response in Oral Human Cells. An In Vitro Infection Model

PubMed Central

Benso, Bruna; Rosalen, Pedro Luiz; Alencar, Severino Matias; Murata, Ramiro Mendonça

2015-01-01

The aim of this study was to investigate the in vitro anti-inflammatory activity of Malva sylvestris extract (MSE) and fractions in a co-culture model of cells infected by Aggregatibacter actinomycetemcomitans. In addition, we evaluated the phytochemical content in the extract and fractions of M. sylvestris and demonstrated that polyphenols were the most frequent group in all samples studied. An in vitro dual-chamber model to mimic the periodontal structure was developed using a monolayer of epithelial keratinocytes (OBA-9) and a subepithelial layer of fibroblasts (HGF-1). The invasive periodontopathogen A. actinomycetemcomitans (D7S-1) was applied to migrate through the cell layers and induce the synthesis of immune factors and cytokines in the host cells. In an attempt to analyze the antimicrobial properties of MSE and fractions, a susceptibility test was carried out. The extract (MIC 175 μg/mL, MBC 500μg/mL) and chloroform fraction (MIC 150 μg/mL, MBC 250 μg/mL) were found to have inhibitory activity. The extract and all fractions were assessed using a cytotoxicity test and results showed that concentrations under 100 μg/mL did not significantly reduce cell viability compared to the control group (p > 0.05, viability > 90%). In order to analyze the inflammatory response, transcriptional factors and cytokines were quantified in the supernatant released from the cells. The chloroform fraction was the most effective in reducing the bacterial colonization (p< 0.05) and controlling inflammatory mediators, and promoted the down-regulation of genes including IL-1beta, IL-6, IL-10, CD14, PTGS, MMP-1 and FOS as well as the reduction of the IL-1beta, IL-6, IL-8 and GM-CSF protein levels (p< 0.05). Malva sylvestris and its chloroform fraction minimized the A. actinomycetemcomitans infection and inflammation processes in oral human cells by a putative pathway that involves important cytokines and receptors. Therefore, this natural product may be considered as a

Effect of photoactivated disinfection with a light-emitting diode on bacterial species and biofilms associated with periodontitis and peri-implantitis.

PubMed

Eick, Sigrun; Markauskaite, Giedre; Nietzsche, Sandor; Laugisch, Oliver; Salvi, Giovanni E; Sculean, Anton

2013-05-01

To determine the effect of photoactivated disinfection (PAD) using toluidine blue and a light-emitting diode (LED) in the red spectrum (wave length at 625-635 nm) on species associated with periodontitis and peri-implantitis and bacteria within a periodontopathic biofilm. Sixteen single microbial species including 2 Porphyromonas gingivalis and 2 Aggregatibacter actinomycetemcomitans and a multispecies mixture consisting of 12 species suspended in saline without and with 25% human serum were exposed to PAD. Moreover, single-species biofilms consisting of 2 P. gingivalis and 2 A. actinomycetemcomitans strains and a multi-species biofilm on 24-well-plates, grown on titanium discs and in artificial periodontal pockets were exposed to PAD with and without pretreatment with 0.25% hydrogen peroxide. Changes in the viability were determined by counting the colony forming units (cfu). PAD reduced the cfu counts in saline by 1.42 log₁₀ after LED application for 30s and by 1.99 log₁₀ after LED application for 60s compared with negative controls (each p<0.001). Serum did not inhibit the efficacy of PAD. PAD reduced statistically significantly (p<0.05) the cfu counts of the P. gingivalis biofilms. The viability of the A. actinomycetemcomitans biofilms and the multi-species biofilms was statistically significantly decreased when PAD was applied after a pretreatment with 0.25% hydrogen peroxide. The biofilm formed in artificial pockets was more sensitive to PAD with and without pretreatment with hydrogen peroxide compared with those formed on titanium discs. PAD using a LED was effective against periodontopathic bacterial species and reduced viability in biofilms but was not able to completely destroy complex biofilms. The use of PAD following pretreatment with hydrogen peroxide resulted in an additional increase in the antimicrobial activity which may represent a new alternative to treat periodontal and peri-implant infections thus warranting further testing in clinical

Inhibition of proinflammatory activities of major periodontal pathogens by aqueous extracts from elder flower (Sambucus nigra).

PubMed

Harokopakis, Evlambia; Albzreh, Mohamad H; Haase, Elaine M; Scannapieco, Frank A; Hajishengallis, George

2006-02-01

Prolonged induction of excessive levels of inflammatory mediators contributes to the pathogenesis of chronic disease states, such as periodontitis. It is thus important to develop safe and effective anti-inflammatory strategies for therapeutic reasons. In this study, we determined the ability of aqueous extracts from elder flower (Sambucus nigra) to inhibit the proinflammatory activity of major virulence factors from the periodontal pathogens Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. Monocytes/macrophages or neutrophils were incubated with whole cells of P. gingivalis, A. actinomycetemcomitans, or purified components thereof (lipopolysaccharide and fimbriae) in the absence or presence of elder flower extract and were assayed for cytokine production, integrin activation, or induction of the oxidative burst. The elder flower extract was found to potently inhibit all proinflammatory activities tested. Investigation of the underlying mechanisms revealed that the anti-inflammatory extract inhibited activation of the nuclear transcription factor kappaB and of phosphatidylinositol 3-kinase. The elder flower extract displays useful anti-inflammatory properties that could be exploited therapeutically for the control of inflammation in human periodontitis.

A possible mechanism of maxillofacial abscess formation: involvement of Porphyromonas endodontalis lipopolysaccharide via the expression of inflammatory cytokines.

PubMed

Murakami, Y; Hanazawa, S; Tanaka, S; Iwahashi, H; Yamamoto, Y; Fujisawa, S

2001-12-01

In a previous study, we developed a specific monoclonal antibody against Porphyromonas endodontalis lipopolysaccharide, and demonstrated that this lipopolysaccharide was detected in bacterially infected root canal fluid. We suggest here that P. endodontalis lipopolysaccharide in the infectious materials plays a stimulatory role in maxillofacial abscess formation via the expression of inflammatory cytokines. Our epidemiological study showed that this lipopolysaccharide was detected in significant levels the infectious material of patients with periapical periodontitis and odontogenic abscesses. Interestingly, infectious material-induced expression of tumor necrosis factor-alpha, interleukin-1beta, or neutrophil chemoattractant KC genes in mouse macrophages, was significantly neutralized by monoclonal antibody against the lipopolysaccharide. In addition, we also detected a significant amount of tumor necrosis factor-alpha in the infectious material. These results suggest that P. endodontalis lipopolysaccharide plays an important role in the pathogenic mechanism of maxillofacial abscess formation via the expression of inflammatory cytokines.

Lipopolysaccharide Density and Structure Govern the Extent and Distance of Nanoparticle Interaction with Actual and Model Bacterial Outer Membranes

DOE PAGES

Jacobson, Kurt H.; Gunsolus, Ian L.; Kuech, Thomas R.; ...

2015-07-24

We report that design of nanomedicines and nanoparticle-based antimicrobial and antifouling formulations, and assessment of the potential implications of nanoparticle release into the environment require understanding nanoparticle interaction with bacterial surfaces. Here we demonstrate electrostatically driven association of functionalized nanoparticles with lipopolysaccharides of Gram-negative bacterial outer membranes and find that lipopolysaccharide structure influences the extent and location of binding relative to the lipid-solution interface. By manipulating the lipopolysaccharide content in Shewanella oneidensis outer membranes, we observed electrostatically driven interaction of cationic gold nanoparticles with the lipopolysaccharide-containing leaflet. We probed this interaction by quartz crystal microbalance with dissipation monitoring (QCM-D) andmore » second harmonic generation (SHG) using solid-supported lipopolysaccharide-containing bilayers. Association of cationic nanoparticles increased with lipopolysaccharide content, while no association of anionic nanoparticles was observed. The harmonic-dependence of QCM-D measurements suggested that a population of the cationic nanoparticles was held at a distance from the outer leaflet-solution interface of bilayers containing smooth lipopolysaccharides (those bearing a long O-polysaccharide). Additionally, smooth lipopolysaccharides held the bulk of the associated cationic particles outside of the interfacial zone probed by SHG. Lastly, our results demonstrate that positively charged nanoparticles are more likely to interact with Gram-negative bacteria than are negatively charged particles, and this interaction occurs primarily through lipopolysaccharides.« less

Transcranial magnetic stimulation modifies astrocytosis, cell density and lipopolysaccharide levels in experimental autoimmune encephalomyelitis.

PubMed

Medina-Fernández, Francisco J; Luque, Evelio; Aguilar-Luque, Macarena; Agüera, Eduardo; Feijóo, Montserrat; García-Maceira, Fe I; Escribano, Begoña M; Pascual-Leone, Álvaro; Drucker-Colín, René; Túnez, Isaac

2017-01-15

Experimental autoimmune encephalomyelitis (EAE) is considered a valid experimental model for multiple sclerosis, a chronic neuroinflammatory condition of the central nervous system. Additionally, some evidence has shown that some microbial products such as the bacterial lipopolysaccharide could lead to the activation of reactive immune cells, triggering neuroinflammation. Several studies have found that transcranial magnetic stimulation (TMS) may exert a neuroprotective effect. Therefore, we aimed to assess the effect of TMS on the neuroinflammation occurring in EAE. A total of 44 male Dark Agouti rats were used. EAE induction was performed administering subcutaneously at the dorsal base of the tail a single dose of myelin oligodendrocyte glycoprotein. Clinical evaluation of motor symptoms was performed. Brain and spinal cord were collected and analyzed for nitric oxide, bacterial lipopolysaccharide and lipopolysaccharide-binding protein. We also carried out a histologic exam, which included an astrocyte immunostaining and Nissl staining for the assessment of brain cell density and pyknotic nuclei. TMS effectively ameliorated motor impairment secondary to EAE. This form of magnetic field was capable of decreasing the proliferation of astrocytes as a response to the autoimmune attack, reducing the content of nitric oxide, bacterial lipopolysaccharide and lipopolysaccharide-binding protein in central nervous system. Moreover, in treated animals, brain cell density was improved and the number of pyknotic nuclei was decreased. Transcranial magnetic stimulation modifies astrocytosis, cell density and lipopolysaccharide levels in EAE. These results suggest that TMS could be a promising treatment for neuroinflammatory conditions such as multiple sclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Quaternized Zn(II) phthalocyanines for photodynamic strategy against resistant periodontal bacteria.

PubMed

Kussovski, Vesselin; Mantareva, Vanya; Durmuş, Mahmut; Angelov, Ivan

2018-04-25

Photodynamic inactivation (PDI) has been featured as an effective strategy in the treatment of acute drug-resistant infections. The efficiency of PDI was evaluated against three periodontal pathogenic bacteria that were tested as drug-resistant strains. In vitro studies were performed with four water-soluble cationic Zn(II) phthalocyanines (ZnPc1-4) and irradiation of a specific light source (light-emitting diode, 665 nm) with three doses (15, 36 and 60 J/cm2). The well detectable fluorescence of ZnPcs allowed the cellular imaging, which suggested relatively high uptakes of ZnPcs into bacterial species. Complete photoinactivation was achieved with all studied ZnPc1-4 for Enterococcus faecalis (E. faecalis) at a light dose of 15 J/cm2. The photodynamic response was high for Prevotella intermedia (P. intermedia) after the application of 6 μM of ZnPc1 and a light dose of 36 J/cm2 and for 6 μM of ZnPc2 at 60 J/cm2. P. intermedia was inactivated with ZnPc3 (4 log) and ZnPc4 (2 log) with irradiation at an optimal dose of 60 J/cm2. Similar photoinactivation results (2 log) were achieved for Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) treated with 6 μM ZnPc1 and ZnPc2 at a light dose of 60 J/cm2. The study suggested that PDI with quaternized Zn(II) phthalocyanines and specific light irradiation appears to be a very useful antimicrobial strategy for effective inactivation of drug-resistant periodontal pathogens.

Prevalence of periodontopathogens and Candida spp. in smokers after nonsurgical periodontal therapy - a pilot study.

PubMed

Camargo, Gabriela Alessandra da Cruz Galhardo; Abreu, Mariana Gouvêa Latini; Cordeiro, Renata Dos Santos; Wenderoscky, Letícia de Farias; Duque, Cristiane

2016-08-22

This pilot study aimed to evaluate the influence of smoking on clinical and microbiological parameters after nonsurgical periodontal therapy. Forty-eight subjects were grouped into smokers (SM, n = 24) and nonsmokers (NS, n = 24) and paired according to gender, age, ethnicity, and periodontal status. Both groups received oral hygiene education and scaling and root planing. Clinical evaluation was performed using plaque index (PI), bleeding on probing (BOP), pocket probing depth (PPD), gingival recession (GR), and clinical attachment level (CAL) before instrumentation (baseline) and at 3 and 6 months. The prevalence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Candida albicans, Candida glabrata, Candida tropicalis, and Candida dubliniensis in subgingival biofilm was determined by polymerase chain reaction. The data were statistically analyzed considering p < 0.05. Clinical conditions improved between baseline and 3 months after periodontal treatment. However, NS had a better clinical response, presenting greater PPD reduction and CAL increase in comparison to SM. Periodontal treatment reduced the levels of P. gingivalis, A. actinomycetemcomitans, and T. forsythia individually after 3 months for the NS group and after 6 months for both groups. The prevalence of Candida species was markedly higher in SM than in NS at all time points evaluated. Periodontopathogens associated or not with C. albicans or C. dubliniensis were more prevalent in SM than in NS at baseline and after 3 months. It was concluded that smoking impairs clinical and microbiological responses to periodontal therapy. Periodontopathogens combined or not with some Candida species are resistant to short-term periodontal therapy in SM.

Genetic characteristics and pathogenic mechanisms of periodontal pathogens.

PubMed

Amano, A; Chen, C; Honma, K; Li, C; Settem, R P; Sharma, A

2014-05-01

Periodontal disease is caused by a group of bacteria that utilize a variety of strategies and molecular mechanisms to evade or overcome host defenses. Recent research has uncovered new evidence illuminating interesting aspects of the virulence of these bacteria and their genomic variability. This paper summarizes some of the strategies utilized by the major species - Aggregatibacter actinomycetemcomitans, Tannerella forsythia, Treponema denticola, and Porphyromonas gingivalis - implicated in the pathogenesis of periodontal disease. Whole-genome sequencing of 14 diverse A. actinomycetemcomitans strains has revealed variations in their genetic content (ranging between 0.4% and 19.5%) and organization. Strikingly, isolates from human periodontal sites showed no genomic changes during persistent colonization. T. forsythia manipulates the cytokine responses of macrophages and monocytes through its surface glycosylation. Studies have revealed that bacterial surface-expressed O-linked glycans modulate T-cell responses during periodontal inflammation. Periodontal pathogens belonging to the "red complex" consortium express neuraminidases, which enables them to scavenge sialic acid from host glycoconjugates. Analysis of recent data has demonstrated that the cleaved sialic acid acts as an important nutrient for bacterial growth and a molecule for the decoration of bacteria surfaces to help evade the host immune attack. In addition, bacterial entry into host cells is also an important prerequisite for the lifestyle of periodontal pathogens such as P. gingivalis. Studies have shown that, after its entry into the cell, this bacterium uses multiple sorting pathways destined for autophagy, lysosomes, or recycling pathways. In addition, P. gingivalis releases outer membrane vesicles which enter cells via endocytosis and cause cellular functional impairment.

Lactobacillus salivarius NK02: a Potent Probiotic for Clinical Application in Mouthwash.

PubMed

Sajedinejad, Neda; Paknejad, Mojgan; Houshmand, Behzad; Sharafi, Hakimeh; Jelodar, Reza; Shahbani Zahiri, Hossein; Noghabi, Kambiz Akbari

2017-06-19

A specific strain of naturally occurring oral lactobacilli was isolated and identified based on morphological, biochemical, and 16S rRNA gene sequencing. The phylogenetic affiliation of the isolate confirmed that the NK02 strain had close association with the Lactobacillus salivarius. An effective mouthwash was developed for treatment of periodontitis and suppression of the indicator bacterium Aggregatibacter actinomycetemcomitans which is an obvious pathogen of periodontal disease. The mouthwash containing L. salivarius NK02 was tested at a dose level of 10 8 (colony forming units (CFU) ml -1 ), monitoring over a period of 4 weeks. The study was a randomized double-blind placebo control trial, and the patients were treated in two groups of control and test by using scaling and root planing (SRP) + placebo and scaling and root planing (SRP) + probiotic, respectively. It appeared that the probiotic mouthwash was able to inhibit the bacterial growth on both saliva and sub-gingival crevice and exhibited antibacterial activity against A. actinomycetemcomitans. The results also showed that SRP+ probiotic treatment led to a significant decrease of gingival index (GI) and bleeding on probing (BOP) compared with that of SRP + placebo for the probiotic group. The rate of decrease in pocket depth was displayed in the group with SRP + probiotic treatment equal to 1/2 mm, and probing pocket depth (PPD) value was decreased in the probiotic bacteria treatment group that can explain the decrease in inflammation in gingiva. Our findings suggest that probiotic mouthwash is healthy for daily use as an alternative for maintaining dental and periodontal health.

Protective effects of a selective neutrophil elastase inhibitor (sivelestat) on lipopolysaccharide-induced acute dysfunction of the pulmonary microcirculation.

PubMed

Inoue, Yoshiaki; Seiyama, Akitoshi; Tanaka, Hiroshi; Ukai, Isao; Akimau, Pavel; Nishino, Masato; Shimazu, Takeshi; Sugimoto, Hisashi

2005-08-01

The purpose of this study was to evaluate the effect of a neutrophil elastase inhibitor, sivelestat, on lipopolysaccharide-induced acute lung injury through analysis of hemodynamic changes in the pulmonary microcirculation. Randomized animal study. Medical school laboratory. Twenty-seven Wistar rats (15 rats for microspectroscopic observations, 12 rats for measurements of neutrophil elastase activity and wet-to-dry ratio). Thoracosternotomy was performed on male Wistar rats under continuous anesthesia and mechanical ventilation. Rats were divided into three groups (n = 5 each groups) on the basis of the reagent used: lipopolysaccharide group (100 microg/kg lipopolysaccharide intravenously), sivelestat group (10 mg/kg sivelestat; 100 microg/kg lipopolysaccharide intravenously), and control group (saline only, intravenously). We measured morphologic changes and hemodynamic variables, including tissue blood flow, erythrocyte velocity, erythrocyte count, thickness of interalveolar septa, and leukocyte adhesion in the pulmonary microcirculation, with a video-rate (33 msec/frame) dual-spot microspectroscopy system (DSMSS) and a laser-Doppler flowmeter. Blood-free wet-to-dry ratio and neutrophil elastase activity in bronchoalveolar lavage fluid, serum, and supernatant of lung homogenate were measured in another set of experiments (n = 4 for each group). Sixty minutes after lipopolysaccharide administration, severe thickening of the interalveolar septa was observed in the lipopolysaccharide but not the sivelestat group. In the lipopolysaccharide group, DSMSS measurements of erythrocyte velocity and hemoglobin oxygenation in single capillaries were decreased significantly (vs. control p < .05, vs. sivelestat p < .01), whereas tissue blood flow and erythrocyte velocity measurements from laser-Doppler flowmeter were increased significantly (vs. control p < .05, vs. sivelestat p < .01). The number of adherent leukocytes was increased significantly in the lipopolysaccharide

Comparative and network-based proteomic analysis of low dose ethanol- and lipopolysaccharide-induced macrophages.

PubMed

Kamal, Abu Hena M; Fessler, Michael B; Chowdhury, Saiful M

2018-01-01

Macrophages are specialized phagocytes that play an essential role in inflammation, immunity, and tissue repair. Profiling the global proteomic response of macrophages to microbial molecules such as bacterial lipopolysaccharide is key to understanding fundamental mechanisms of inflammatory disease. Ethanol is a widely abused substance that has complex effects on inflammation. Reports have indicated that ethanol can activate or inhibit the lipopolysaccharide receptor, Toll-like Receptor 4, in different settings, with important consequences for liver and neurologic inflammation, but the underlying mechanisms are poorly understood. To profile the sequential effect of low dose ethanol and lipopolysaccharide on macrophages, a gel-free proteomic technique was applied to RAW 264.7 macrophages. Five hundred four differentially expressed proteins were identified and quantified with high confidence using ≥ 5 peptide spectral matches. Among these, 319 proteins were shared across all treatment conditions, and 69 proteins were exclusively identified in ethanol-treated or lipopolysaccharide-stimulated cells. The interactive impact of ethanol and lipopolysaccharide on the macrophage proteome was evaluated using bioinformatics tools, enabling identification of differentially responsive proteins, protein interaction networks, disease- and function-based networks, canonical pathways, and upstream regulators. Five candidate protein coding genes (PGM2, ISYNA1, PARP1, and PSAP) were further validated by qRT-PCR that mostly related to glucose metabolism and fatty acid synthesis pathways. Taken together, this study describes for the first time at a systems level the interaction between ethanol and lipopolysaccharide in the proteomic programming of macrophages, and offers new mechanistic insights into the biology that may underlie the impact of ethanol on infectious and inflammatory disease in humans.

Comparative and network-based proteomic analysis of low dose ethanol- and lipopolysaccharide-induced macrophages

PubMed Central

Kamal, Abu Hena M.; Fessler, Michael B.

2018-01-01

Macrophages are specialized phagocytes that play an essential role in inflammation, immunity, and tissue repair. Profiling the global proteomic response of macrophages to microbial molecules such as bacterial lipopolysaccharide is key to understanding fundamental mechanisms of inflammatory disease. Ethanol is a widely abused substance that has complex effects on inflammation. Reports have indicated that ethanol can activate or inhibit the lipopolysaccharide receptor, Toll-like Receptor 4, in different settings, with important consequences for liver and neurologic inflammation, but the underlying mechanisms are poorly understood. To profile the sequential effect of low dose ethanol and lipopolysaccharide on macrophages, a gel-free proteomic technique was applied to RAW 264.7 macrophages. Five hundred four differentially expressed proteins were identified and quantified with high confidence using ≥ 5 peptide spectral matches. Among these, 319 proteins were shared across all treatment conditions, and 69 proteins were exclusively identified in ethanol-treated or lipopolysaccharide-stimulated cells. The interactive impact of ethanol and lipopolysaccharide on the macrophage proteome was evaluated using bioinformatics tools, enabling identification of differentially responsive proteins, protein interaction networks, disease- and function-based networks, canonical pathways, and upstream regulators. Five candidate protein coding genes (PGM2, ISYNA1, PARP1, and PSAP) were further validated by qRT-PCR that mostly related to glucose metabolism and fatty acid synthesis pathways. Taken together, this study describes for the first time at a systems level the interaction between ethanol and lipopolysaccharide in the proteomic programming of macrophages, and offers new mechanistic insights into the biology that may underlie the impact of ethanol on infectious and inflammatory disease in humans. PMID:29481576

Influence UHF radiation on the process of self-assembly and lethal effect of bacterial lipopolysaccharide

NASA Astrophysics Data System (ADS)

Brill, G. E.; Egorova, A. V.; Bugaeva, I. O.; Postnov, D. E.; Melnikov, A. G.; Ushakova, O. V.

2018-04-01

The influence of low-intensity electromagnetic radiation on the process of self-assembly, spectral-fluorescent characteristics and lethal effect of bacterial lipopolysaccharide (endotoxin) was performed. A solution of bacterial lipopolysaccharide exposed to electromagnetic waves with a frequency of 1 GHz, the power density of 0.1 μW/cm2 for 10 min. In experiments on a large group of control and irradiated mice, a comparative analysis of the estimated lethal dose of endotoxin was performed. It was proved that UHF radiation of certain parameters reduces the lethal effects of bacterial lipopolysaccharide on 26%.

The effect of lipopolysaccharide-induced obesity and its chronic inflammation on influenza virus-related pathology.

PubMed

Ahn, Sun-Young; Sohn, Sung-Hwa; Lee, Sang-Yeon; Park, Hye-Lim; Park, Yong-Wook; Kim, Hun; Nam, Jae-Hwan

2015-11-01

Obese individuals show increased susceptibility to infection, low vaccine efficacy, and worse pathophysiology. However, it is unclear how obesity affects these events. The aim of this study was to investigate the effect of obesity-triggered chronic inflammation on immune cells after influenza virus infection. Control and lipopolysaccharide mice, in which an osmotic pump continually released Tween saline or lipopolysaccharide, were prepared and 3 weeks later were infected with pandemic H1N1 2009 influenza A virus. In lipopolysaccharide mice, we found a reduction in macrophage activation markers in the steady state, and reduced production of pro-inflammatory cytokines including tumor necrosis factor-α, interleukin-1β, and interleukin-6, in restimulated peritoneal macrophages. Interestingly, lipopolysaccharide-triggered chronic inflammation exacerbated the severity of pathological symptoms in the lungs after challenge with influenza virus. Taken together, the increased severity of virus-induced symptoms in obese individuals with chronic inflammation may be, at least partially, caused by macrophage dysfunction. Copyright © 2015 Elsevier B.V. All rights reserved.

Proteomic analysis of macrophage activated with salmonella lipopolysaccharide

USDA-ARS?s Scientific Manuscript database

Macrophages play pivotal role in immunity. They are activated by many pathogen derived molecules such as lipopolysaccharides (LPS) which trigger the production of various proteins and peptides that drive and resolve inflammation. There are numerous studies on the effect of LPS at the genome level bu...

Antimicrobial activity of isothiocyanates (ITCs) extracted from horseradish (Armoracia rusticana) root against oral microorganisms.

PubMed

Park, Ho-Won; Choi, Kyu-Duck; Shin, Il-Shik

2013-01-01

The antimicrobial activity of isothiocyanates (ITCs) extracted from horseradish root was investigated against oral microorganisms: 6 strains of facultative anaerobic bacteria, Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei, Staphylococcus aureus, Enterococcus faecalis and Aggregatibacter actinomycetemcomitans; one strain of yeast, Candida albicans, and 3 strains of anaerobic bacteria, Fusobacterium nucleatum, Prevotella nigrescens, and Clostridium perfringens. The ITCs extracted from horseradish root showed antimicrobial activity against all oral microorganisms by the paper disk method. The minimum bactericidal concentration (MBC) of the ITCs extracted from horseradish root ranged from 1.25 to 5.00 mg/ml against 6 strains of facultative anaerobic bacteria and one strain of yeast, and 4.17 to 16.67 mg/ml against 3 strains of anaerobic bacteria. The ITCs extracted from horseradish root showed the strongest antimicrobial activity, with a MBC of 1.25 mg/ml, against C. albicans among facultative microorganisms, and 4.17 mg/ml against F. nucleatum among anaerobic bacteria. These results suggest that the ITCs extracted from horseradish root may be a candidate for use as an antimicrobial agent against oral microorganisms.

Incidence of periodontitis in Japanese patients with cardiovascular diseases: a comparison between abdominal aortic aneurysm and arrhythmia.

PubMed

Suzuki, Jun-Ichi; Aoyama, Norio; Aoki, Mieko; Tada, Yuko; Wakayama, Kouji; Akazawa, Hiroshi; Shigematsu, Kunihiro; Hoshina, Katsuyuki; Izumi, Yuichi; Komuro, Issei; Miyata, Tetsuro; Hirata, Yasunobu; Isobe, Mitsuaki

2015-07-01

Although there is a link between periodontitis and cardiovascular disease (CVD), the influence of periodontitis on CVD is unclear. The aim of this study was to assess the relationship between periodontal bacterial burden and CVD. We studied 142 patients with tachyarrhythmia (TA) and 25 patients with abdominal aortic aneurysm (AAA). We examined periodontitis and the presence of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans and Prevotella intermedia in the patients' saliva and subgingival plaque using PCR. We also measured serum antibody titers against the pathogens using ELISA. We found that the patients with AAA had fewer remaining teeth (14.6 ± 2.0 vs. 20.9 ± 0.7, P < 0.05) and deeper pocket depth (3.01 ± 0.26 vs. 2.52 ± 0.05 mm, P < 0.05) compared to the TA patients. The existence of each periodontal bacterium in their saliva or subgingival plaque and serum antibody titers was comparable between the two groups. Periodontitis may have a larger affect on aneurysm progression compared to arrhythmia.

Microarray Analysis of Microbiota of Gingival Lesions in Noma Patients

PubMed Central

Huyghe, Antoine; François, Patrice; Mombelli, Andrea; Tangomo, Manuela; Girard, Myriam; Baratti-Mayer, Denise; Bolivar, Ignacio; Pittet, Didier; Schrenzel, Jacques

2013-01-01

Noma (cancrum oris) is a gangrenous disease of unknown etiology affecting the maxillo-facial region of young children in extremely limited resource countries. In an attempt to better understand the microbiological events occurring during this disease, we used phylogenetic and low-density microarrays targeting the 16S rRNA gene to characterize the gingival flora of acute noma and acute necrotizing gingivitis (ANG) lesions, and compared them to healthy control subjects of the same geographical and social background. Our observations raise doubts about Fusobacterium necrophorum, a previously suspected causative agent of noma, as this species was not associated with noma lesions. Various oral pathogens were more abundant in noma lesions, notably Atopobium spp., Prevotella intermedia, Peptostreptococcus spp., Streptococcus pyogenes and Streptococcus anginosus. On the other hand, pathogens associated with periodontal diseases such as Aggregatibacter actinomycetemcomitans, Capnocytophaga spp., Porphyromonas spp. and Fusobacteriales were more abundant in healthy controls. Importantly, the overall loss of bacterial diversity observed in noma samples as well as its homology to that of ANG microbiota supports the hypothesis that ANG might be the immediate step preceding noma. PMID:24086784

Detection of five potentially periodontal pathogenic bacteria in peri-implant disease: A comparison of PCR and real-time PCR.

PubMed

Schmalz, Gerhard; Tsigaras, Sandra; Rinke, Sven; Kottmann, Tanja; Haak, Rainer; Ziebolz, Dirk

2016-07-01

The aim of this study was to compare the microbial analysis methods of polymerase chain reaction (PCR) and real-time PCR (RT-PCR) in terms of detection of five selected potentially periodontal pathogenic bacteria in peri-implant disease. Therefore 45 samples of healthy, mucositis and peri-implantitis (n = 15 each) were assessed according to presence of the following bacteria using PCR (DNA-strip technology) and RT-PCR (fluorescent dye SYBR green-system): Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Treponema denticola (Td), Tanerella forsythia (Tf), and Fusobacterium nucleatum (Fn). There were no significant correlations between the bacterial and disease patterns, so the benefit of using microbiological tests for the diagnosis of peri-implant diseases is questionable. Correlations between the methods were highest for Tf (Kendall's Tau: 0.65, Spearman: 0.78), Fn (0.49, 0.61) and Td (0.49, 0.59). For Aa (0.38, 0.42) and Pg (0.04, 0.04), lower correlation values were detected. Accordingly, conventional semi-quantitative PCR seems to be sufficient for analyzing potentially periodontal pathogenic bacterial species. Copyright © 2016 Elsevier Inc. All rights reserved.

Structural and functional peculiarities of the lipopolysaccharide of Azospirillum brasilense SR55, isolated from the roots of Triticum durum.

PubMed

Boyko, Alevtina S; Konnova, Svetlana A; Fedonenko, Yulia P; Zdorovenko, Evelina L; Smol'kina, Olga N; Kachala, Vadim V; Ignatov, Vladimir V

2011-10-20

Azospirillum brasilense SR55, isolated from the rhizosphere of Triticum durum, was classified as serogroup II on the basis of serological tests. Such serogroup affiliation is uncharacteristic of wheat-associated Azospirillum species. The lipid A of A. brasilense SR55 lipopolysaccharide contained 3-hydroxytetradecanoic, 3-hydroxyhexadecanoic, hexadecanoic and octadecenoic fatty acids. The structure of the lipopolysaccharide's O polysaccharide was established, with the branched octasaccharide repeating unit being represented by l-rhamnose, l-3-O-Me-rhamnose, d-galactose and d-glucuronic acid. The SR55 lipopolysaccharide induced deformations of wheat root hairs. The lipopolysaccharide was not involved in bacterial cell aggregation, but its use to pretreat wheat roots was conducive to cell adsorption. This study shows that Azospirillum bacteria can utilise their own lipopolysaccharide as a carbon source, which may give them an advantage in competitive natural environments. Copyright © 2011 Elsevier GmbH. All rights reserved.

Antimicrobial activity of polyhexamethylene guanidine phosphate in comparison to chlorhexidine using the quantitative suspension method.

PubMed

Vitt, A; Sofrata, A; Slizen, V; Sugars, R V; Gustafsson, A; Gudkova, E I; Kazeko, L A; Ramberg, P; Buhlin, K

2015-07-17

Polyhexamethylene guanidine phosphate (PHMG-P) belongs to the polymeric guanidine family of biocides and contains a phosphate group, which may confer better solubility, a detoxifying effect and may change the kinetics and dynamics of PHMG-P interactions with microorganisms. Limited data regarding PHMG-P activity against periodontopathogenic and cariogenic microorganisms necessitates studies in this area. Aim is to evaluate polyhexamethylene guanidine phosphate antimicrobial activity in comparison to chlorhexidine. Quantitative suspension method was used enrolling Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Streptococcus mutans and Lactobacillus acidophilus. Both tested antiseptics at their clinically-used concentrations, of 0.2% (w/v) and 1% (w/v), correspondingly provided swift bactericidal effects against S. aureus, P. aeruginosa, E. coli and C. albicans, A. actinomycetemcomitans and P. gingivalis with reduction factors higher than 6.0. Diluted polyhexamethylene guanidine phosphate and chlorhexidine to 0.05% continued to display anti-bacterial activity and decreased titers of standard quality control, periopathogens to below 1.0 × 10(3) colony forming units/ml, albeit requiring prolonged exposure time. To achieve a bactericidal effect against S. mutans, both antiseptics at all concentrations required a longer exposure time. We found that a clinically-used 1% of polyhexamethylene guanidine phosphate concentration did not have activity against L. acidophilus. High RF of polyhexamethylene guanidine phosphate and retention of bactericidal effects, even at 0.05%, support the use of polyhexamethylene guanidine phosphate as a biocide with sufficient anti-microbial activity against periopathogens. Polyhexamethylene guanidine phosphate displayed bactericidal activity against periopathogens and S. mutans and could potentially be applied in the management of oral

Protective effect of mangiferin against lipopolysaccharide-induced depressive and anxiety-like behaviour in mice.

PubMed

Jangra, Ashok; Lukhi, Manish M; Sulakhiya, Kunjbihari; Baruah, Chandana C; Lahkar, Mangala

2014-10-05

Numerous studies have demonstrated that inflammation, oxidative stress and altered level of neurotrophins are involved in the pathogenesis of depressive illness. Mangiferin, a C-glucosylxanthone is abundant in the stem and bark of Mangifera indica L. The compound has been shown to possess antioxidant, anti-inflammatory and immunomodulatory activities. The present study was performed to investigate the effect of mangiferin pretreatment on lipopolysaccharide-induced increased proinflammatory cytokines, oxidative stress and neurobehavioural abnormalities. Mice were challenged with lipopolysaccharide (0.83 mg/kg, i.p.) after 14 days of mangiferin (20 and 40 mg/kg, p.o.) pretreatment. Mangiferin pretreatment significantly ameliorated the anxiety-like behaviour as evident from the results of an elevated plus maze, light-dark box and open field test. Mangiferin pretreatment also improved the anhedonic behaviour as revealed by sucrose preference test and increased social interaction time. It also prevented the lipopolysaccharide-evoked depressive-like effect by reducing the immobility time in forced swim and tail suspension test. Lipopolysaccharide-induced elevated oxidative stress was decreased with mangiferin pretreatment due to its potential to increase reduced glutathione concentration, Superoxide dismutase and catalase activity and decrease lipid peroxidation and nitrite level in the hippocampus as well as in the prefrontal cortex. Mangiferin pretreatment also attenuated neuroinflammation by reducing the interleukin-1 beta (IL-1β) level in hippocampus and prefrontal cortex. In conclusion, our results demonstrated that mangiferin possessed antidepressant and anti-anxiety properties due to its ability to attenuate IL-1β level and oxidative stress evoked by intraperitoneal administration of lipopolysaccharide. Mangiferin may be a potential therapeutic agent for the treatment of depressive and anxiety illness. Copyright © 2014. Published by Elsevier B.V.

Chemical composition of lipopolysaccharides isolated from various endophytic nitrogen-fixing bacteria of the genus Herbaspirillum.

PubMed

Serrato, R V; Sassaki, G L; Cruz, L M; Carlson, R W; Muszyński, A; Monteiro, R A; Pedrosa, F O; Souza, E M; Iacomini, M

2010-04-01

Bacteria from the genus Herbaspirillum are endophytes responsible for nitrogen fixation in gramineous plants of economic importance such as maize, sugarcane, sorghum, rice, and wheat. Some species are known to produce plant growth substances. In contrast, Herbaspirillum rubrisubalbicans strains are known to be mild plant pathogens. The molecular communication between the plant and the microbes might involve lipopolysaccharides present in the outer membrane of these gram-negative bacteria. Phenol-water extraction was used to obtain lipopolysaccharides from 7 strains of Herbaspirillum seropedicae (SmR1, Z67, Z78, ZA95, and M2) and H. rubrisubalbicans (M1 and M4). The electrophoretic profiles and chemical composition of the lipopolysaccharides obtained in the phenol and aqueous extracts were shown herein.

Proteins required for lipopolysaccharide assembly in Escherichia coli form a transenvelope complex.

PubMed

Chng, Shu-Sin; Gronenberg, Luisa S; Kahne, Daniel

2010-06-08

The viability of Gram-negative organisms is dependent on the proper placement of lipopolysaccharide (LPS) in the outer leaflet of its outer membrane. LPS is synthesized inside the cell and transported to the surface by seven essential lipopolysaccharide transport (Lpt) proteins. How these proteins cooperate to transport LPS is unknown. We show that these Lpt proteins can be found in a membrane fraction that contains inner and outer membranes and that they copurify. This constitutes the first evidence that the Lpt proteins form a transenvelope complex. We suggest that this protein bridge provides a route for LPS transport across the cell envelope.

Rodent nutritional model of steatohepatitis: effects of endotoxin (lipopolysaccharide) and tumor necrosis factor alpha deficiency.

PubMed

Kirsch, Richard; Clarkson, Vivian; Verdonk, Robert C; Marais, Adrian D; Shephard, Enid G; Ryffel, Bernard; de la M Hall, Pauline

2006-01-01

Intestinal endotoxin (lipopolysaccharide) is thought to contribute to liver injury in both alcoholic and nonalcoholic steatohepatitis (NASH). Tumor necrosis factor alpha (TNFalpha) is an important mediator of this process and is considered central to the inflammatory response in NASH. This study aimed to investigate the effects of lipopolysaccharide on liver injury in the methionine choline deficient (MCD) nutritional model of NASH, and to determine if TNFalpha is required for the development of steatohepatitis in this model. Male C57/BL6 mice received a MCD diet for 4 weeks, whilst a control group received an identical diet supplemented with 0.2% choline bitartrate and 0.3% methionine. At 4 weeks, mice received either an intraperitoneal injection of lipopolysaccharide (0.5 microg/g body mass) or sterile saline, and were killed 24 h thereafter. In a separate study, TNFalpha knockout and wild type C57BL/6 mice received either MCD or control diets for 4 weeks. Serum transaminase levels, liver histology (steatosis, inflammation and apoptosis), hepatic triglyceride concentration and hepatic lipid peroxidation products (conjugated dienes, lipid hydroperoxides and thiobarbituric reactive substances, free and total) were evaluated. Intraperitoneal administration of lipopolysaccharide augmented serum alanine aminotransferase (ALT) levels (P<0.02), hepatic inflammation (P<0.025), apoptosis (P<0.01) and free thiobarbituric acid reactive substances (P<0.025) in MCD mice. TNFalpha knockout mice fed the MCD diet developed steatohepatitis with histological and biochemical changes similar to those seen in wild type counterparts. Lipopolysaccharide augments liver injury in MCD mice, and TNFalpha is not required for the development of steatohepatitis in MCD mice.

Interleukin-6 production by human monocytes treated with granulocyte-macrophage colony-stimulating factor in the presence of lipopolysaccharide of oral microorganisms.

PubMed

Baqui, A A; Meiller, T F; Chon, J J; Turng, B F; Falkler, W A

1998-06-01

This study focused on the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) and lipopolysaccharide of the putative periodontal pathogens Porphyromonas gingivalis or Fusobacterium nucleatum on IL-6 production by THP-1 cells (a human monocytic cell line). Resting THP-1 cells were alternatively treated with GM-CSF (50 IU/ml) and lipopolysaccharide of P. gingivalis or F. nucleatum, in varying concentrations for varying time periods. IL-6 production in supernatant fluids of treated cells was evaluated by an enzyme-linked immunosorbent assay (ELISA) and a reverse transcription polymerase chain reaction (RT-PCR) was used to evaluate gene expression. Untreated THP-1 cells did not produce IL-6 as determined by ELISA. RT-PCR also failed to detect IL-6 mRNA in untreated THP-1 cells, indicating that IL-6 was not constitutively produced. After stimulation of THP-1 cells with lipopolysaccharide of F. nucleatum or P. gingivalis, IL-6 was produced, peaking at 4 h (200-300 pg/ml) and thereafter sharply declining by 8 h. When GM-CSF was added together with lipopolysaccharide of P. gingivalis or F. nucleatum, there was a synergistic quantitative increase in production of IL-6 as measured by ELISA as compared with lipopolysaccharide alone. IL-6 mRNA was detected by RT-PCR, 15 min after stimulation with lipopolysaccharide of either P. gingivalis or F. nucleatum. GM-CSF supplementation with lipopolysaccharide of P. gingivalis shortened the transcription of IL-6 mRNA to 5 min, a shift which was not observed with lipopolysaccharide of F. nucleatum, possibly indicating a different mechanism of initiation of transcription. Production of IL-6 by GM-CSF-treated THP-1 cells in the presence of lipopolysaccharide of oral microorganisms may provide a model for studying the role of macrophages in acute and chronic periodontal diseases, including the clinical periodontal exacerbation as observed in chemotherapy patients receiving GM-CSF for bone marrow recovery.

Proteomic changes in chicken plasma induced by Salmonella typhimurium lipopolysaccharides

USDA-ARS?s Scientific Manuscript database

Lipopolysaccharides (LPS) are cell wall components of gram-negative bacteria that cause inflammation and sickness through genetic and proteomic activation. The objective of our study was to identify the proteomic changes in plasma associated with inflammation induced by LPS treatment. Five-week-old ...

[Erythropoietin influence on oxygen transport function of blood and prooxidant/antioxidant balance in rabbits under lipopolysaccharide injection].

PubMed

Zinchuk, V V; Shul'ga, E V; Guliaĭ, I E

2010-01-01

We aimed to study the erythropoietin influence on oxygen transport function of blood and prooxidant/antioxidant balance in rabbits under lipopolysaccharide injection. Recombinant human erythropoietin-alpha was administered intraperitoneally in the dose 1000 U/kg 30 minutes before intravenous injection of 500 mkg/kg lipopolysaccharide from E. coli. After 12 hours, blood samples were collected for the assessment of oxygen transport function of blood; nitrate/nitrite levels and tissue samples were collected for measurement of conjugated dienes, malondialdehyde, alpha-tocopherol and catalase. Erythropoietin improves parameters of oxygen transport function of blood, increases hemoglobin-oxygen affinity through the NO-dependent mechanism, reduces activity of free radical processes, and increases antioxidant protection under lipopolysaccharide injection.

Association of red complex, A. actinomycetemcomitans and non-oral bacteria with periodontal diseases.

PubMed

da Silva-Boghossian, Carina Maciel; do Souto, Renata Martins; Luiz, Ronir R; Colombo, Ana Paula Vieira

2011-09-01

Pathogens related to systemic infections have been detected in the periodontal microbiota. The relationship amongst these pathogens, periodontal bacteria and periodontal clinical status is poorly understood. This study evaluated the association amongst red complex, A. actinomycetemcomitans (A.a) and non-oral pathogenic bacteria in subjects with good periodontal health (PH), gingivitis (G), chronic (CP) and aggressive (AP) periodontitis. Subgingival biofilm samples were obtained from 51 PH, 42 G, 219 CP and 90 AP subjects. The presence and levels of A.a, red complex (Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola), Acinetobacter baumannii, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, and Staphylococcus aureus were determined by DNA probes and DNA-DNA hybridization technique. CP and AP subjects presented significantly higher prevalence and levels of A.a, red complex and A. baumannii than G and PH individuals (p<0.01), whereas S. aureus was detected in lower frequency and counts in AP as compared to the other groups (p<0.001). The predictor variables age, prevalence of red complex, and the presence of A. baumannii and P. aeruginosa were strongly associated with the frequency of sites with PD and CAL ≥5 mm. Increasing age (OR 1.08), high frequency of red complex (OR 6.10), and the presence of A.a with P. aeruginosa (OR 1.90) were associated with periodontal disease (p<0.001). Subjects harbouring a high prevalence of A.a, A. baumannii, and red complex with P. aeruginosa were more likely to have AP than CP (p<0.001). Putative periodontal pathogens and non-oral bacteria alone or in association were strongly associated with periodontitis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Influence of Periodontal Therapy on Systemic Lipopolysaccharides in Children with Localized Aggressive Periodontitis.

PubMed

Kalash, D; Vovk, A; Huang, H; Aukhil, I; Wallet, S M; Shaddox, L M

2015-01-01

A previous study has shown that children with localized aggressive periodontitis (LAP) demonstrate a lipopolysaccharide (LPS) hyper-responsiveness in addition to elevated levels of systemic LPS when compared to periodontally healthy children. The purpose of this study was to evaluate whether periodontal therapy modulates systemic lipopolysaccharide levels and whether these levels may influence clinical outcomes. Peripheral blood samples and clinical parameters (probing depth [PD], clinical attachment levels [CAL], percent sites greater than four mm, bleeding on probing [BoP], and visible plaque [P]) were collected from 29 LAP patients prior to and at three, six, and 12 months following scaling and root planning and systemic antibiotics. Serum LPS levels were quantified using a chromogenic assay. Twenty-five patients were compliant with the prescribed antibiotic treatment and demonstrated a significant reduction in LPS as well as overall PD, CAL, and plaque at all time points post-therapy. Additionally LPS reductions correlated with reductions in PD, CAL, and plaque. Localized aggressive periodontitis therapy with antibiotics plays an important role in reducing systemic lipopolysaccharide levels. Since LPS is a key mediator of the LAP hyperinflammatory response, its systemic reduction is especially important for the successful management of these children.

Plant Proanthocyanidins Bind to and Neutralize Bacterial Lipopolysaccharides

DTIC Science & Technology

2008-01-01

2008 NRL REVIEW 101 Plant Proanthocyanidins Bind to and Neutralize Bacterial Lipopolysaccharides J.B. Delehanty,1 B.J. Johnson,1 T.E. Hickey,1 T...polymers derived from higher plants and they have recently been associated with several potential positive health benefits such as antibacterial...and 2) a core oligosaccharide region which gives rise to 3) the O-antigen, a branched polysaccharide that extends from the core oligosaccharide .2

Does pregnancy have an impact on the subgingival microbiota?

PubMed

Adriaens, Laurence M; Alessandri, Regina; Spörri, Stefan; Lang, Niklaus P; Persson, G Rutger

2009-01-01

We investigated clinical and subgingival microbiologic changes during pregnancy in 20 consecutive pregnant women > or =18 years not receiving dental care. Bacterial samples from weeks 12, 28, and 36 of pregnancy and at 4 to 6 weeks postpartum were processed for 37 species by checkerboard DNA-DNA hybridization. Clinical periodontal data were collected at week 12 and at 4 to 6 weeks postpartum, and bleeding on probing (BOP) was recorded at sites sampled at the four time points. The mean BOP at week 12 and postpartum was 40.1% +/- 18.2% and 27.4% +/- 12.5%, respectively. The corresponding mean BOP at microbiologic test sites was 15% (week 12) and 21% (postpartum; not statistically significant). Total bacterial counts decreased between week 12 and postpartum (P <0.01). Increased bacterial counts over time were found for Neisseria mucosa (P <0.001). Lower counts (P <0.001) were found for Capnocytophaga ochracea, Capnocytophaga sputigena, Eubacterium saburreum, Fusobacterium nucleatum naviforme, Fusobacterium nucleatum polymorphum, Leptotrichia buccalis, Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Prevotella intermedia, Prevotella melaninogenica, Staphylococcus aureus, Streptococcus anginosus, Streptococcus intermedius, Streptococcus mutans, Streptococcus oralis, Streptococcus sanguinis, Selenomonas noxia, and Veillonella parvula. No changes occurred between weeks 12 and 28 of pregnancy. Counts of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), and Treponema denticola did not change. Counts of P. gingivalis and T. forsythia at week 12 were associated with gingivitis (P <0.001). Subgingival levels of bacteria associated with periodontitis did not change. P. gingivalis and T. forsythia counts were associated with BOP at week 12. A decrease was found in 17 of 37 species from week 12 to postpartum. Only counts of N. mucosa

Release of metronidazole from electrospun poly(L-lactide-co-D/L-lactide) fibers for local periodontitis treatment.

PubMed

Reise, Markus; Wyrwa, Ralf; Müller, Ulrike; Zylinski, Matthias; Völpel, Andrea; Schnabelrauch, Matthias; Berg, Albrecht; Jandt, Klaus D; Watts, David C; Sigusch, Bernd W

2012-02-01

We aimed to achieve detailed biomaterials characterization of a drug delivery system for local periodontitis treatment based on electrospun metronidazole-loaded resorbable polylactide (PLA) fibers. PLA fibers loaded with 0.1-40% (w/w) MNA were electrospun and were characterized by SEM and DSC. HPLC techniques were used to analyze the release profiles of metronidazole (MNA) from these fibers. The antibacterial efficacy was determined by measuring inhibition zones of drug-containing aliquots from the same electrospun fiber mats in an agar diffusion test. Three pathogenic periodontal bacterial strains: Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were studied. Cytotoxicity testing was performed with human gingival fibroblasts by: (i) counting viable cells via live/dead staining methods and (ii) by exposing cells directly onto the surface of MNA-loaded fibers. MNA concentration influenced fiber diameters and thus w/w surface areas: diameter being minimal and area maximal at 20% MNA. HPLC showed that these 20% MNA fibers had the fastest initial MNA release. From the third day, MNA release was slower and nearly linear with time. All fiber mats released 32-48% of their total drug content within the first 7 days. Aliquots of media taken from the fiber mats inhibited the growth of all three bacterial strains. MNA released up to the 28th day from fiber mats containing 40% MNA significantly decreased the viability of F. nucleatum and P. gingivalis and up to the 2nd day also for the resistant A. actinomycetemcomitans. All of the investigated fibers and aliquots showed excellent cytocompatibility. This study shows that MNA-loaded electrospun fiber mats represent an interesting class of resorbable drug delivery systems. Sustained drug release properties and cytocompatibility suggest their potential clinical applicability for the treatment of periodontal diseases. Copyright © 2011 Academy of Dental Materials. Published by Elsevier

Increased levels of Porphyromonas gingivalis are associated with ischemic and hemorrhagic cerebrovascular disease in humans: an in vivo study

PubMed Central

GHIZONI, Janaina Salomon; TAVEIRA, Luís Antônio de Assis; GARLET, Gustavo Pompermaier; GHIZONI, Marcos Flávio; PEREIRA, Jefferson Ricardo; DIONÍSIO, Thiago José; BROZOSKI, Daniel Thomas; SANTOS, Carlos Ferreira; SANT'ANA, Adriana Campos Passanezi

2012-01-01

Objective: This study investigated the role of periodontal disease in the development of stroke or cerebral infarction in patients by evaluating the clinical periodontal conditions and the subgingival levels of periodontopathogens. Material and Methods: Twenty patients with ischemic (I-CVA) or hemorrhagic (H-CVA) cerebrovascular episodes (test group) and 60 systemically healthy patients (control group) were evaluated for: probing depth, clinical attachment level, bleeding on probing and plaque index. Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were both identified and quantified in subgingival plaque samples by conventional and real-time PCR, respectively. Results: The test group showed a significant increase in each of the following parameters: pocket depth, clinical attachment loss, bleeding on probing, plaque index and number of missing teeth when compared to control values (p<0.05, unpaired t-test). Likewise, the test group had increased numbers of sites that were contaminated with P. gingivalis (60%x10%; p<0.001; chi-squared test) and displayed greater prevalence of periodontal disease, with an odds ratio of 48.06 (95% CI: 5.96-387.72; p<0.001). Notably, a positive correlation between probing depth and the levels of P. gingivalis in ischemic stroke was found (r=0.60; p=0.03; Spearman's rank correlation coefficient test). A. actinomycetemcomitans DNA was not detected in any of the groups by conventional or real-time PCR. Conclusions: Stroke patients had deeper pockets, more severe attachment loss, increased bleeding on probing, increased plaque indexes, and in their pockets harbored increased levels of P. gingivalis. These findings suggest that periodontal disease is a risk factor for the development of cerebral hemorrhage or infarction. Early treatment of periodontitis may counteract the development of cerebrovascular episodes. PMID:22437687

Smoking-related cotinine levels and host responses in chronic periodontitis.

PubMed

Ebersole, J L; Steffen, M J; Thomas, M V; Al-Sabbagh, M

2014-10-01

Smoking has been reported to increase the risk of periodontal disease by disrupting the balance of immune responses and tissue repair processes; however, this risk varies among smokers. Cotinine levels in saliva are routinely used to measure the level of smoking, and reflect the quantity of nicotine, and other smoking-related xenobiotics that challenge host systems. This study delineated characteristics of inflammatory mediators in saliva and serum antibody responses to both periodontal pathogens and commensal bacteria in smokers as they related to cotinine levels. This case-control study (n = 279) examined salivary inflammatory mediator responses [interleukin (IL)-1ß, IL-10, prostaglandin E2, myeloperoxidase and plasminogen activator inhibitor-1], and serum IgG antibody responses to three periodontal pathogens (Aggregatibacter actinomyce-temcomitans, Porphyromonas gingivalis, Treponema denticola) and five commensal oral microorganisms (Veillonella parvula, Streptococcus sanguis, Prevotella loescheii, Actinomyces naeslundii, Capnocytophaga ochracea). The patients were stratified into health (n = 30), gingivitis (n = 55) and periodontitis (n = 184); cotinine levels correlated with reported smoking habits in health, less so with gingivitis, and were not correlated in periodontitis. Of the inflammatory mediators/acute phase proteins, only IL-1ß levels were positively associated (p < 0.001) with the pack years and cotinine levels. As might be predicted, patients with periodontitis smoked more (p < 0.001) and had higher levels of cotinine. IL-1ß and antibody to A. actinomycetemcomitans, P. gingivalis and T. denticola were significantly higher in the patients with periodontitis than either patients with gingivitis or who were healthy. Generally, antibody to the pathogens and commensals was lower with decreased cotinine levels. Smoking exacerbated differences in both inflammatory mediators and three antibody in periodontal disease compared to healthy

Photodynamic therapy as an adjunct to non-surgical periodontal treatment: a randomized, controlled clinical trial.

PubMed

Christodoulides, Nicos; Nikolidakis, Dimitris; Chondros, Panagiotis; Becker, Jürgen; Schwarz, Frank; Rössler, Ralf; Sculean, Anton

2008-09-01

Recent preclinical and clinical data have suggested a potential benefit of photodynamic therapy (PDT) in the treatment of periodontitis. However, there are very limited data from controlled clinical trials evaluating the effect of PDT in the treatment of periodontitis. The aim of this study was to evaluate the clinical and microbiologic effects of the adjunctive use of PDT to non-surgical periodontal treatment. Twenty-four subjects with chronic periodontitis were randomly treated with scaling and root planing followed by a single episode of PDT (test) or scaling and root planing alone (control). Full-mouth plaque score (FMPS), full-mouth bleeding score (FMBS), probing depth (PD), gingival recession, and clinical attachment level (CAL) were measured at baseline and 3 and 6 months after therapy. Primary outcome variables were changes in PD and CAL. Microbiologic evaluation of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia (previously T. forsythensis), Treponema denticola, Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Fusobacterium nucleatum, Campylobacter rectus, Eubacterium nodatum, Eikenella corrodens, and Capnocytophaga spp. was performed at baseline and 3 and 6 months following therapy by using a commercially available polymerase chain reaction test. At 3 and 6 months after treatment, there were no statistically significant differences between the groups with regard to CAL, PD, FMPS, or microbiologic changes. At 3 and 6 months, a statistically significantly greater improvement in FMBS was found in the test group. The additional application of a single episode of PDT to scaling and root planing failed to result in an additional improvement in terms of PD reduction and CAL gain, but it resulted in a significantly higher reduction in bleeding scores compared to scaling and root planing alone.

C-reactive protein as a systemic marker of inflammation in periodontitis.

PubMed

Pejcic, A; Kesic, L J; Milasin, J

2011-03-01

Periodontitis has been identified as a potential risk factor for systemic pathologies such as cardiovascular disease (CVD). The aims of this investigation were to assess the relationship between periodontitis and systemic inflammatory factor, as well as to discover whether there is a relation to the severity of periodontitis and to the periodontopathogens. Periodontal examinations and serum C-reactive protein (CRP) level measurements were performed in 50 patients with periodontitis. Periodontal health indicators included the gingival bleeding on probing index and periodontal disease status. The patients with moderate periodontitis had low attachment loss and pocket depth <4 mm. The patients with severe periodontitis had high attachment loss and pocket depth >5 mm. The control group comprised 25 volunteers with healthy gingiva, gingival sulcus <2 mm and no attachment loss. The presence of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans in subgingival plaque samples was analysed by the polymerase chain reaction (PCR) method. The periodontal parameters and CRP levels were significantly higher in the patients with periodontitis. Patients who had severe periodontitis, with high levels of mean clinical attachment loss, and subjects with moderate periodontitis had higher mean CRP levels. The percentage of subjects with elevated levels of CRP >5 mg/l was greater in the higher clinical attachment loss group compared to the group with lower attachment loss. The presence of P. gingivalis and A. actinomycetemcomitans were also associated with elevated CRP levels and poor periodontal status. Periodontitis and the presence of P. gingivalis are associated with an enhanced inflammatory response expressed by higher CRP levels. The association of periodontitis with CRP levels appears to be a contributing factor for CVD and might be a possible intermediate pathway in this association.

In-vitro activity of taurolidine on single species and a multispecies population associated with periodontitis.

PubMed

Zollinger, Lilly; Schnyder, Simone; Nietzsche, Sandor; Sculean, Anton; Eick, Sigrun

2015-04-01

The antimicrobial activity of taurolidine was compared with minocycline against microbial species associated with periodontitis (four single strains and a 12-species mixture). Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs), killing as well as activities on established and forming single-species biofilms and a 12-species biofilm were determined. The MICs of taurolidine against single species were always 0.31 mg/ml, the MBCs were 0.64 mg/ml. The used mixed microbiota was less sensitive to taurolidine, MIC and the MBC was 2.5 mg/ml. The strains and the mixture were completely killed by 2.5 mg/ml taurolidine, whereas 256 μg/ml minocycline reduced the bacterial counts of the mixture by 5 log10 colony forming units (cfu). Coating the surface with 10 mg/ml taurolidine or 256 μg/ml minocycline prevented completely biofilm formation of Porphyromonas gingivalis ATCC 33277 but not of Aggregatibacter actinomycetemcomitans Y4 and the mixture. On 4.5 d old biofilms, taurolidine acted concentration dependent with a reduction by 5 log10 cfu (P. gingivalis ATCC 33277) and 7 log10 cfu (A. actinomycetemcomitans Y4) when applying 10 mg/ml. Minocycline decreased the cfu counts by 1-2 log10 cfu independent of the used concentration. The reduction of the cfu counts in the 4.5 d old multi-species biofilms was about 3 log10 cfu after application of any minocycline concentration and after using 10 mg/ml taurolidine. Taurolidine is active against species associated with periodontitis, even within biofilms. Nevertheless a complete elimination of complex biofilms by taurolidine seems to be impossible and underlines the importance of a mechanical removal of biofilms prior to application of taurolidine. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lipopolysaccharide based oral nanocarriers for the improvement of bioavailability and anticancer efficacy of curcumin.

PubMed

Chaurasia, Sundeep; Patel, Ravi R; Chaubey, Pramila; Kumar, Nagendra; Khan, Gayasuddin; Mishra, Brahmeshwar

2015-10-05

Soluthin MD(®), a unique phosphatidylcholine-maltodextrin based hydrophilic lipopolysaccharide, which exhibits superior biocompatibility and bioavailability enhancer properties for poorly water soluble drug(s). Curcumin (CUR) is a potential natural anticancer drug with low bioavailability due to poor aqueous solubility. The study aims at formulation and optimization of CUR loaded lipopolysaccharide nanocarriers (C-LPNCs) to enhance oral bioavailability and anticancer efficacy in colon-26 tumor-bearing mice in vitro and in vivo. The Optimized C-LPNCs demonstrated favorable mean particle size (108 ± 3.4 nm) and percent entrapment efficiency (65.29 ± 1.0%). Pharmacokinetic parameters revealed ∼130-fold increase in oral bioavailability and cytotoxicity studies demonstrated ∼23-fold reduction in 50% cell growth inhibition when treated with optimized C-LPNCs as compared to pure CUR. In vivo anticancer study performed with optimized C-LPNCs showed significant increase in efficacy compared with pure CUR. Thus, lipopolysaccharide nanocarriers show potential delivery strategy to improve oral bioavailability and anticancer efficacy of CUR in the treatment of colorectal cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.

New Features in the Lipid A Structure of Brucella suis and Brucella abortus Lipopolysaccharide

NASA Astrophysics Data System (ADS)

Casabuono, Adriana C.; Czibener, Cecilia; Del Giudice, Mariela G.; Valguarnera, Ezequiel; Ugalde, Juan E.; Couto, Alicia S.

2017-12-01

Brucellaceae are Gram-negative bacteria that cause brucellosis, one of the most distributed worldwide zoonosis, transmitted to humans by contact with either infected animals or their products. The lipopolysaccharide exposed on the cell surface has been intensively studied and is considered a major virulence factor of Brucella. In the last years, structural studies allowed the determination of new structures in the core oligosaccharide and the O-antigen of this lipopolysaccharide. In this work, we have reinvestigated the lipid A structure isolated from B. suis and B. abortus lipopolysaccharides. A detailed study by MALDI-TOF mass spectrometry in the positive and negative ion modes of the lipid A moieties purified from both species was performed. Interestingly, a new feature was detected: the presence of a pyrophosphorylethanolamine residue substituting the backbone. LID-MS/MS analysis of some of the detected ions allowed assurance that the Lipid A structure composed by the diGlcN3N disaccharide, mainly hexa-acylated and penta-acylated, bearing one phosphate and one pyrophosphorylethanolamine residue. [Figure not available: see fulltext.

New Features in the Lipid A Structure of Brucella suis and Brucella abortus Lipopolysaccharide.

PubMed

Casabuono, Adriana C; Czibener, Cecilia; Del Giudice, Mariela G; Valguarnera, Ezequiel; Ugalde, Juan E; Couto, Alicia S

2017-12-01

Brucellaceae are Gram-negative bacteria that cause brucellosis, one of the most distributed worldwide zoonosis, transmitted to humans by contact with either infected animals or their products. The lipopolysaccharide exposed on the cell surface has been intensively studied and is considered a major virulence factor of Brucella. In the last years, structural studies allowed the determination of new structures in the core oligosaccharide and the O-antigen of this lipopolysaccharide. In this work, we have reinvestigated the lipid A structure isolated from B. suis and B. abortus lipopolysaccharides. A detailed study by MALDI-TOF mass spectrometry in the positive and negative ion modes of the lipid A moieties purified from both species was performed. Interestingly, a new feature was detected: the presence of a pyrophosphorylethanolamine residue substituting the backbone. LID-MS/MS analysis of some of the detected ions allowed assurance that the Lipid A structure composed by the diGlcN3N disaccharide, mainly hexa-acylated and penta-acylated, bearing one phosphate and one pyrophosphorylethanolamine residue. Graphical abstract ᅟ.

Strawberry extracts efficiently counteract inflammatory stress induced by the endotoxin lipopolysaccharide in Human Dermal Fibroblast.

PubMed

Gasparrini, Massimiliano; Giampieri, Francesca; Forbes-Hernandez, Tamara Y; Afrin, Sadia; Cianciosi, Danila; Reboredo-Rodriguez, Patricia; Varela-Lopez, Alfonso; Zhang, JiaoJiao; Quiles, Josè L; Mezzetti, Bruno; Bompadre, Stefano; Battino, Maurizio

2018-04-01

A protracted pro-inflammatory state is the common denominator in the development, progression and complication of the common chronic diseases. Dietary antioxidants represent an efficient tool to counteract this inflammatory state. The aim of the present work was to evaluate the effects of strawberry extracts on inflammation evoked by E. Coli lipopolysaccharide in Human Dermal Fibroblast, by measuring reactive oxygen species production, apoptosis rate, antioxidant enzymes activity, mitochondria functionality and also investigating the molecular pathway involved in inflammatory and antioxidant response. The results demonstrated that strawberry pre-treatment reduced intracellular reactive oxygen species levels, apoptotic rate, improved antioxidant defences and mitochondria functionality in lipopolysaccharide -treated cells. Strawberry exerted these protective activities through the inhibition of the NF-kB signalling pathway and the stimulation of the Nrf2 pathway, with a mechanism AMPK-dependent. These results confirm the health benefits of strawberry in the prevention of inflammation and oxidative stress condition in lipopolysaccharide-treated cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

Sirtuin inhibition attenuates the production of inflammatory cytokines in lipopolysaccharide-stimulated macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandes, Claudia A.; Fievez, Laurence; Neyrinck, Audrey M.

Highlights: Black-Right-Pointing-Pointer Lipopolysaccharide-stimulated macrophages were treated with cambinol and sirtinol. Black-Right-Pointing-Pointer Cambinol and sirtinol decreased lipopolysaccharide-induced cytokines. Black-Right-Pointing-Pointer Cambinol decreased NF-{kappa}B activity but had no impact on p38 MAPK activation. Black-Right-Pointing-Pointer Sirtuins are an interesting target for the treatment of inflammatory diseases. -- Abstract: In several inflammatory conditions such as rheumatoid arthritis or sepsis, the regulatory mechanisms of inflammation are inefficient and the excessive inflammatory response leads to damage to the host. Sirtuins are class III histone deacetylases that modulate the activity of several transcription factors that are implicated in immune responses. In this study, we evaluated the impact ofmore » sirtuin inhibition on the activation of lipopolysaccharide (LPS)-stimulated J774 macrophages by assessing the production of inflammatory cytokines. The pharmacologic inhibition of sirtuins decreased the production of tumour necrosis factor-alpha (TNF-{alpha}) interleukin 6 (IL-6) and Rantes. The reduction of cytokine production was associated with decreased nuclear factor kappa B (NF-{kappa}B) activity and inhibitor kappa B alpha (I{kappa}B{alpha}) phosphorylation while no impact was observed on the phosphorylation status of p38 mitogen-activated kinase (p38 MAPK). This work shows that sirtuin pharmacologic inhibitors are a promising tool for the treatment of inflammatory conditions.« less

The antimicrobial efficacy of commercial dentifrices.

PubMed

Haraszthy, Violet I; Zambon, Joseph J; Sreenivasan, Prem K

2010-01-01

This investigation compared the effects of a fluoride dentifrice and toothpastes formulated with antimicrobial ingredients (stannous fluoride and triclosan/copolymer) on oral micro-organisms, including those found in samples taken from the human oral cavity. Microbiological techniques determined the minimum inhibitory concentrations (MICs) of each dentifrice necessary to inhibit the growth of bacterial strains from the healthy oral cavity, as well as those found in dental caries, periodontal disease, and halitosis. Ex vivo studies utilized oral rinse samples and supragingival plaque from adults to determine antimicrobial effects on the entire microbial diversity of these samples, including biofilm-derived micro-organisms. The triclosan/copolymer dentifrice demonstrated the lowest MICs and significantly inhibited Gram-positive and Gram-negative bacteria (including the periodontal pathogens Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum). In the ex vivo tests, the triclosan/copolymer dentifrice demonstrated substantial inhibition in the oral rinse samples over each treatment period (p > 0.0005) as compared to either the fluoride or stannous fluoride dentifrices. Similarly, the triclosan/copolymer dentifrice demonstrated the highest inhibition of micro-organisms in the supragingival plaque biofilm (p < 0.0005). No significant differences were observed between the fluoride and stannous fluoride dentifrices (p > 0.5).

Effect of green tea catechin, a local drug delivery system as an adjunct to scaling and root planing in chronic periodontitis patients: A clinicomicrobiological study

PubMed Central

Kudva, Praveen; Tabasum, Syeda Tawkhira; Shekhawat, Nirmal Kanwar

2011-01-01

Background: Evaluate the adjunctive use of locally delivered green tea catechin with scaling and root planing, as compared to scaling and root planing alone in the management of chronic periodontitis. Materials and Methods: Fourteen patients with two sites in the contralateral quadrants with probing pocket depth of 5–8mm were selected. Each of the sites was assessed for the plaque index, gingival index, and probing pocket depth at baseline and 21 days and for microbiological analysis at baseline, 1 week and 21 days. Test sites received scaling and root planing along with green tea catechin strips and control sites received scaling and root planning alone. Results: The result showed intercomparison of the plaque index and gingival index for test and control groups at 21 days was not significant with P>0.05, whereas the probing depth at 21 days was significant with P<0.001. Intercomparison between microbial results demonstrated a considerable reduction of occurrence of Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Fusobacterium species and Capnocytophaga in test. Conclusion: Green tea catechin local delivery along with scaling and root planing is more effective than scaling and root planing alone. PMID:21772720

Oral microbiota in youth with perinatally acquired HIV infection.

PubMed

Starr, Jacqueline R; Huang, Yanmei; Lee, Kyu Ha; Murphy, C M; Moscicki, Anna-Barbara; Shiboski, Caroline H; Ryder, Mark I; Yao, Tzy-Jyun; Faller, Lina L; Van Dyke, Russell B; Paster, Bruce J

2018-05-31

Microbially mediated oral diseases can signal underlying HIV/AIDS progression in HIV-infected adults. The role of the oral microbiota in HIV-infected youth is not known. The Adolescent Master Protocol of the Pediatric HIV/AIDS Cohort Study is a longitudinal study of perinatally HIV-infected (PHIV) and HIV-exposed, uninfected (PHEU) youth. We compared oral microbiome levels and associations with caries or periodontitis in 154 PHIV and 100 PHEU youth. Species richness and alpha diversity differed little between PHIV and PHEU youth. Group differences in average counts met the significance threshold for six taxa; two Corynebacterium species were lower in PHIV and met thresholds for noteworthiness. Several known periodontitis-associated organisms (Prevotella nigrescens, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, and Filifactor alocis) exhibited expected associations with periodontitis in PHEU youth, associations not observed in PHIV youth. In both groups, odds of caries increased with counts of taxa in four genera, Streptococcus, Scardovia, Bifidobacterium, and Lactobacillus. The microbiomes of PHIV and PHEU youth were similar, although PHIV youth seemed to have fewer "health"-associated taxa such as Corynebacterium species. These results are consistent with the hypothesis that HIV infection, or its treatment, may contribute to oral dysbiosis.

Simultaneous detection of periodontal pathogens in subgingival plaque and placenta of women with hypertension in pregnancy.

PubMed

Swati, P; Thomas, Betsy; Vahab, Saadi Abdul; Kapaettu, Satyamoorthy; Kushtagi, Pralhad

2012-03-01

There are many studies documenting increased prevalence of periodontal infection in women with preeclampsia. But, very few studies have attempted to establish causal relationship between the two. To find out causal circumstantial evidence by isolating specific periodontal pathogens in oral and placental samples. Antenatal periodontal screening and subgingival plaque collection was carried out in ten women with hypertension in pregnancy and ten normotensive controls on their hospital admission at term for cesarean delivery. Placental biopsy was obtained after aseptic placental collection at the time of elective cesarean delivery. Subgingival plaque and placental biopsy were studied for Porphyromonas gingivalis, Fusobacterium nucleatum, Treponema denticola, Prevotella intermedia and Aggregatibacter actinomycetemcomitans using quantitative polymerase chain reaction technique. Periodontist and laboratory personnel were unaware of case or control status. Periodontal status was not informed to the obstetrician recruiting the cases and laboratory. Microbiology report was not revealed till end of the study. Periodontal pathogens were found to be high in the group with hypertension than the controls. P gingivalis was found in all the samples from subgingival plaque and placenta, irrespective of the periodontal disease status. In cases with hypertension, periodontal pathogens are present in higher proportion in subgingival plaque and placenta.

MIF induces osteoclast differentiation and contributes to progression of periodontal disease in mice.

PubMed

Madeira, Mila Fernandes Moreira; Queiroz-Junior, Celso Martins; Costa, Graciela Mitre; Santos, Patrícia Campi; Silveira, Elcia Maria; Garlet, Gustavo Pompermaier; Cisalpino, Patrícia Silva; Teixeira, Mauro Martins; Silva, Tarcília Aparecida; Souza, Daniele da Glória

2012-02-01

Periodontal disease (PD) is a chronic inflammatory and alveolar bone destructive disease triggered by microorganisms from the oral biofilm. Oral inoculation of mice with the periodontopathogen Aggregatibacter actinomycetemcomitans (Aa) induces marked alveolar bone loss and local production of inflammatory mediators, including Macrophage Migration Inhibitory Factor (MIF). The role of MIF for alveolar bone resorption during PD is not known. In the present study, experimental PD was induced in BALB/c wild-type mice (WT) and MIF knockout mice (MIF⁻/⁻) through oral inoculation of Aa. Despite enhanced number of bacteria, MIF⁻/⁻ mice had reduced infiltration of TRAP-positive cells and reduced alveolar bone loss. This was associated with decreased neutrophil accumulation and increased levels of IL-10 in periodontal tissues. TNF-α production was similar in both groups. In vitro, LPS from Aa enhanced osteoclastic activity in a MIF-dependent manner. In conclusion, MIF has role in controlling bacterial growth in the context of PD but contributes more significantly to the progression of bone loss during PD by directly affecting differentiation and activity of osteoclasts. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

The green tea polyphenol (-)-epigallocatechin gallate precipitates salivary proteins including alpha-amylase: biochemical implications for oral health.

PubMed

Hara, Kumiko; Ohara, Masaru; Hayashi, Ikue; Hino, Takamune; Nishimura, Rumi; Iwasaki, Yoriko; Ogawa, Tetsuji; Ohyama, Yoshihiko; Sugiyama, Masaru; Amano, Hideaki

2012-04-01

Green tea is a popular drink throughout the world, and it contains various components, including the green tea polyphenol (-)-epigallocatechin gallate (EGCG). Tea interacts with saliva upon entering the mouth, so the interaction between saliva and EGCG interested us, especially with respect to EGCG-protein binding. SDS-PAGE revealed that several salivary proteins were precipitated after adding EGCG to saliva. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) peptide mass fingerprinting indicated that the major proteins precipitated by EGCG were alpha-amylase, S100, and cystatins. Surface plasmon resonance revealed that EGCG bound to alpha-amylase at dissociation constant (K(d)) = 2.74 × 10(-6) M, suggesting that EGCG interacts with salivary proteins with a relatively strong affinity. In addition, EGCG inhibited the activity of alpha-amylase by non-competitive inhibition, indicating that EGCG is effective at inhibiting the formation of fermentable carbohydrates involved in caries formation. Interestingly, alpha-amylase reduced the antimicrobial activity of EGCG against the periodontal bacterium Aggregatibacter actinomycetemcomitans. Therefore, we considered that EGCG-salivary protein interactions might have both protective and detrimental effects with respect to oral health. © 2012 Eur J Oral Sci.

An improved cost-effective, reproducible method for evaluation of bone loss in a rodent model.

PubMed

Fine, Daniel H; Schreiner, Helen; Nasri-Heir, Cibele; Greenberg, Barbara; Jiang, Shuying; Markowitz, Kenneth; Furgang, David

2009-02-01

This study was designed to investigate the utility of two "new" definitions for assessment of bone loss in a rodent model of periodontitis. Eighteen rats were divided into three groups. Group 1 was infected by Aggregatibacter actinomycetemcomitans (Aa), group 2 was infected with an Aa leukotoxin knock-out, and group 3 received no Aa (controls). Microbial sampling and antibody titres were determined. Initially, two examiners measured the distance from the cemento-enamel-junction to alveolar bone crest using the three following methods; (1) total area of bone loss by radiograph, (2) linear bone loss by radiograph, (3) a direct visual measurement (DVM) of horizontal bone loss. Two "new" definitions were adopted; (1) any site in infected animals showing bone loss >2 standard deviations above the mean seen at that site in control animals was recorded as bone loss, (2) any animal with two or more sites in any quadrant affected by bone loss was considered as diseased. Using the "new" definitions both evaluators independently found that infected animals had significantly more disease than controls (DVM system; p<0.05). The DVM method provides a simple, cost effective, and reproducible method for studying periodontal disease in rodents.

Periodontal bacteria in the genital tract: are they related to adverse pregnancy outcome?

PubMed

Cassini, M A; Pilloni, A; Condò, S G; Vitali, L A; Pasquantonio, G; Cerroni, L

2013-01-01

One of the most important factors implicated in preterm birth (PTB) is acute genitourinary tract infection. The bacteria causing chronic periodontal inflammation include Gram-negative rods and anaerobes similar to those found in women with bacterial vaginosis. The aim of this prospective study is to investigate the relationship between oral and vaginal microflora and preterm low birth weight. Real-time polymerase chain reaction was used to detect both the presence and level of six periodontitis-related species: Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Treponema denticola (Td), Fusobacterium nucleatum ssp(Fn), and Prevotella intermedia (Pi) for both oral samples of subgingival plaque and cervical samples, obtained from 80 patients, during gynaecological examinations. The more representative oral pathogen (less than 60 percent) species in oral samples of preterm and term group were Tf, Td, and Fn. 24.4 percent of pregnant women presented periodontal pathogens in vaginal swab; the most representative species with a percentage over 0.1 percent of total bacteria in genital tract of preterm group were Tf, Td, and Piwith a positive correlation (less than 0.5). The presence of the bacterium T. denticolain the vagina, regardless of the amount, adversely affects preterm delivery.

Lipopolysaccharide-Induced Toxic Shock Syndrome in Rabbits.

PubMed

Stach, Christopher S; Schlievert, Patrick M

2016-01-01

Enhancement of susceptibility to lipopolysaccharide (LPS; endotoxin) is a defining characteristic of Staphylococcus aureus superantigens. At the time of this publication, there are 24 identified staphylococcal superantigens (SAgs), some of which have yet to be fully characterized. Testing the capacity of superantigens to potentiate LPS sensitivity is essential to characterize the role of these proteins in disease development. Here we describe how to perform studies of the enhancement of LPS-induced toxic shock syndrome in rabbits. This protocol also provides information on a second important activity of superantigens: the production of fever.

Coxiella burnetii Lipopolysaccharide: What Do We Know?

PubMed Central

Abnave, Prasad; Muracciole, Xavier; Ghigo, Eric

2017-01-01

A small gram-negative bacterium, Coxiella burnetii (C. burnetii), is responsible for a zoonosis called Q fever. C. burnetii is an intracellular bacterium that can survive inside microbicidal cells like monocytes and macrophages by hijacking several functions of the immune system. Among several virulence factors, the lipopolysaccharide (LPS) of C. burnetii is one of the major factors involved in this immune hijacking because of its atypical composition and structure. Thus, the aim of this mini-review is to summarize the repressive effects of C. burnetii LPS on the antibacterial immunity of cells. PMID:29168790

Influence of corrosion on lipopolysaccharide affinity for two different titanium materials.

PubMed

Barão, Valentim Adelino Ricardo; Mathew, Mathew T; Yuan, Judy Chia-Chun; Knoernschild, Kent L; Assunção, Wirley Gonçalves; Wimmer, Markus A; Sukotjo, Cortino

2013-12-01

Titanium is subject to corrosion in the oral cavity, which could contribute to periimplantitis. However, the effect of corrosion on the lipopolysaccharide affinity for titanium remains unknown. This study evaluated the role of corrosion (in artificial saliva at pHs 3, 6.5, and 9) on the lipopolysaccharide (LPS) affinity for commercially pure titanium (cp-Ti) and Ti-6Al-4V alloy. Seventy-two titanium disks were anodically polarized in a controlled environment (n=9). Control specimens were not corroded. Deionized water with different concentrations of LPS (1.5, 15, and 150 μg/mL) were used to treat the disks for 24 hours to investigate LPS adherence (n=3). Then specimens were immersed in LPS-free water to evaluate LPS elution at 24, 48, and 72 hours. Data were analyzed by the 2-way, 3-way, and 3-way repeated measures ANOVA, t tests, and the Tukey honestly significant difference (HSD) tests (α=.05). A greater corrosion rate of cp-Ti and Ti-6Al-4V alloy and a higher LPS adherence to titanium surfaces (P<.05) were noted at acidic pH. The LPS affinity was higher for the Ti-6Al-4V alloy than for cp-Ti (P<.05). More LPS was eluted from titanium surfaces after a 24-hour interval. Lipopolysaccharide affinity for cp-Ti and Ti-6Al-4V alloy is influenced by the corrosion process. Copyright © 2013 Editorial Council for the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE

EPA Science Inventory

EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE
S. Mundandhara1 and M.C. Madden2, 1UNC Center for Environmental Medicine, Asthma, and Lung Biology, 2US EPA, NHEERL, Human Studies Division, Chapel Hill, NC, USA

Epidemiologica...

Role of outer membrane lipopolysaccharides in the protection of Salmonella enterica serovar Typhimurium from desiccation damage.

PubMed

Garmiri, Penelope; Coles, Karen E; Humphrey, Tom J; Cogan, Tristan A

2008-04-01

The ability to survive desiccation between hosts is often essential to the success of pathogenic bacteria. The bacterial outer membrane is both the cellular interface with hostile environments and the focus of much of the drying-induced damage. This study examined the contribution of outer membrane-associated polysaccharides to the survival of Salmonella enterica serovar Typhimurium in air-dried blood droplets following growth in high and low osmolarity medium and under conditions known to induce expression of these polysaccharides. Strains lacking the O polysaccharide (OPS) element of the outer membrane lipopolysaccharide were more sensitive to desiccation. Lipopolysaccharide core mutation further to OPS loss did not result in increased susceptibility to drying. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed lipopolysaccharide profiles that supported the hypothesis that OPS expression is required for optimal drying resistance in S. Typhimurium. The role of O antigen in Salmonella spp. in maintaining a hydrated layer around the dried cell or in slowing the rate of dehydration and rehydration is discussed.

Green tea polyphenol epigallocatechin-3-gallate and cranberry proanthocyanidins act in synergy with cathelicidin (LL-37) to reduce the LPS-induced inflammatory response in a three-dimensional co-culture model of gingival epithelial cells and fibroblasts.

PubMed

Lombardo Bedran, Telma Blanca; Palomari Spolidorio, Denise; Grenier, Daniel

2015-06-01

The human antimicrobial peptide cathelicidin (LL-37) possesses anti-inflammatory properties that may contribute to attenuating the inflammatory process associated with chronic periodontitis. Plant polyphenols, including those from cranberry and green tea, have been reported to reduce inflammatory cytokine secretion by host cells. In the present study, we hypothesized that A-type cranberry proanthocyanidins (AC-PACs) and green tea epigallocatechin-3-gallate (EGCG) act in synergy with LL-37 to reduce the secretion of inflammatory mediators by oral mucosal cells. A three-dimensional (3D) co-culture model of gingival epithelial cells and fibroblasts treated with non-cytotoxic concentrations of AC-PACs (25 and 50 μg/ml), EGCG (1 and 5 μg/ml), and LL-37 (0.1 and 0.2 μM) individually and in combination (AC-PACs+LL-37 and EGCG+LL-37) were stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS). Multiplex ELISA assays were used to quantify the secretion of 54 host factors, including chemokines, cytokines, growth factors, matrix metalloproteinases (MMPs), and tissue inhibitors of metalloproteinases (TIMPs). LL-37, AC-PACs, and EGCG, individually or in combination, had no effect on the regulation of MMP and TIMP secretion but inhibited the secretion of several cytokines. AC-PACs and LL-37 acted in synergy to reduce the secretion of CXC-chemokine ligand 1 (GRO-α), granulocyte colony-stimulating factor (G-CSF), and interleukin-6 (IL-6), and had an additive effect on reducing the secretion of interleukin-8 (IL-8), interferon-γ inducible protein 10 (IP-10), and monocyte chemoattractant protein-1 (MCP-1) in response to LPS stimulation. EGCG and LL-37 acted in synergy to reduce the secretion of GRO-α, G-CSF, IL-6, IL-8, and IP-10, and had an additive effect on MCP-1 secretion. The combination of LL-37 and natural polyphenols from cranberry and green tea acted in synergy to reduce the secretion of several cytokines by an LPS-stimulated 3D co

[Establishment of a D-galactosamine/lipopolysaccharide induced acute-on-chronic liver failure model in rats].

PubMed

Liu, Xu-hua; Chen, Yu; Wang, Tai-ling; Lu, Jun; Zhang, Li-jie; Song, Chen-zhao; Zhang, Jing; Duan, Zhong-ping

2007-10-01

To establish a practical and reproducible animal model of human acute-on-chronic liver failure for further study of the pathophysiological mechanism of acute-on-chronic liver failure and for drug screening and evaluation in its treatment. Immunological hepatic fibrosis was induced by human serum albumin in Wistar rats. In rats with early-stage cirrhosis (fibrosis stage IV), D-galactosamine and lipopolysaccharide were administered. Mortality and survival time were recorded in 20 rats. Ten rats were sacrificed at 4, 8, and 12 hours. Liver function tests and plasma cytokine levels were measured after D-galactosamine/lipopolysaccharide administration and liver pathology was studied. Cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Most of the rats treated with human albumin developed cirrhosis and fibrosis, and 90% of them died from acute liver failure after administration of D-galactosamine/lipopolysaccharide, with a mean survival time of (16.1+/-3.7) hours. Liver histopathology showed massive or submassive necrosis of the regenerated nodules, while fibrosis septa were intact. Liver function tests were compatible with massive necrosis of hepatocytes. Plasma level of TNFalpha increased significantly, parallel with the degree of the hepatocytes apoptosis. Plasma IL-10 levels increased similarly as seen in patients with acute-on-chronic liver failure. We established an animal model of acute-on-chronic liver failure by treating rats with human serum albumin and later with D-galactosamine and lipopolysaccharide. TNFalpha-mediated liver cell apoptoses plays a very important role in the pathogenesis of acute liver failure.

Oral arginine reduces gut mucosal injury caused by lipopolysaccharide endotoxemia in rat.

PubMed

Sukhotnik, Igor; Mogilner, Jorge; Krausz, Michael M; Lurie, Michael; Hirsh, Mark; Coran, Arnold G; Shiloni, Eitan

2004-12-01

The objective of this study was to evaluate the effects of lipopolysaccharide (LPS) endotoxemia and enteral arginine (ARG) supplementation on intestinal structural changes, enterocyte proliferation, and apoptosis in rat. Male Sprague-Dawley rats, weighing 250-280 g, were divided into three experimental groups: control rats, LPS rats treated with lipopolysaccharide given ip at a dose of 10 mg/kg every 24 h (two injections), and LPS-ARG rats treated with enteral arginine given in drinking water (2%) 72 h before and following injection of LPS. Intestinal structural changes, enterocyte proliferation, and enterocyte apoptosis were determined on day 3 following the first LPS injection. LPS rats demonstrated a significant decrease in bowel weight in duodenum, mucosal weight in duodenum, jejunum, and ileum, mucosal DNA and protein in jejunum and ileum, and villus height in jejunum and ileum compared to control animals. LPS rats also had a significantly lower cell proliferation index in jejunum and ileum and a higher apoptotic index in jejunum and ileum compared to control rats. LPS-ARG animals demonstrated greater duodenal bowel weight, duodenal and ileal mucosal weight, ileal mucosal DNA and protein, ileal villus height, and jejunal and ileal cell proliferation index compared to LPS animals. LPS endotoxemia impairs the integrity of the gastrointestinal mucosa in rat. Decreased cell proliferation and increased apoptosis may be considered the main mechanisms responsible for the decreased cell mass. Enteral arginine administration decreases the mucosal injury caused by lipopolysaccharide.

Comparative airway inflammatory response of normal volunteers to ozone and lipopolysaccharide challenge

EPA Science Inventory

Ozone and lipopolysaccharide (LPS) are environmental pollutants with adverse heatth effects noted in both healthy and asthmatic individuals. The authors and others have shown that inhalation of ozone and LPS both induce airway neutrophilia. Based on these similarities, the author...

EFFECTS OF DIESEL EXHAUST PARTICLES ON HUMAN ALVEOLAR MACROPHAGE RESPONSIVENESS TO LIPOPOLYSACCHARIDE

EPA Science Inventory

Effects of diesel exhaust particles on human alveolar macrophage responsiveness to lipopolysaccharide
S. Mundandhara1 , S. Becker2 and M. Madden2, 1UNC Center for Environmental Medicine, Asthma, and Lung Biology, 2US EPA, NHEERL, HSD, Chapel Hill, NC, US

Epidemiological...

Bacterial Lipopolysaccharide Destabilizes Influenza Viruses.

PubMed

Bandoro, Christopher; Runstadler, Jonathan A

2017-01-01

Depending on the specific viral pathogen, commensal bacteria can promote or reduce the severity of viral infection and disease progression in their hosts. Influenza A virus (IAV) has a broad host range, comprises many subtypes, and utilizes different routes of transmission, including the fecal-oral route in wild birds. It has been previously demonstrated that commensal bacteria can interact with the host's immune system to protect against IAV pathogenesis. However, it is unclear whether bacteria and their products may be interacting directly with IAV to impact virion stability. Herein we show that gastrointestinal (GI) tract bacterial isolates in an in vitro system significantly reduce the stability of IAV. Moreover, bacterial lipopolysaccharide (LPS), found on the exterior surfaces of bacteria, was sufficient to significantly decrease the stability of both human and avian viral strains in a temperature-dependent manner, including at the relevant temperatures of their respective hosts and the external aquatic habitat. The subtype and host origin of the viruses were shown to affect the extent to which IAV was susceptible to LPS. Furthermore, using a receptor binding assay and transmission electron microscopy, we observed that LPS binds to and alters the morphology of influenza virions, suggesting that direct interaction with the viral surface contributes to the observed antiviral effect of LPS on influenza. IMPORTANCE Influenza A virus (IAV), transmitted primarily via the fecal-oral route in wild birds, encounters high concentrations of bacteria and their products. Understanding the extent to which bacteria affect the infectivity of IAV will lead to a broader understanding of viral ecology in reservoir hosts and may lead to insights for the development of therapeutics in respiratory infection. Herein we show that bacteria and lipopolysaccharide (LPS) interact with and destabilize influenza virions. Moreover, we show that LPS reduces the long-term persistence and

Bacterial Lipopolysaccharide Destabilizes Influenza Viruses

PubMed Central

2017-01-01

ABSTRACT Depending on the specific viral pathogen, commensal bacteria can promote or reduce the severity of viral infection and disease progression in their hosts. Influenza A virus (IAV) has a broad host range, comprises many subtypes, and utilizes different routes of transmission, including the fecal-oral route in wild birds. It has been previously demonstrated that commensal bacteria can interact with the host’s immune system to protect against IAV pathogenesis. However, it is unclear whether bacteria and their products may be interacting directly with IAV to impact virion stability. Herein we show that gastrointestinal (GI) tract bacterial isolates in an in vitro system significantly reduce the stability of IAV. Moreover, bacterial lipopolysaccharide (LPS), found on the exterior surfaces of bacteria, was sufficient to significantly decrease the stability of both human and avian viral strains in a temperature-dependent manner, including at the relevant temperatures of their respective hosts and the external aquatic habitat. The subtype and host origin of the viruses were shown to affect the extent to which IAV was susceptible to LPS. Furthermore, using a receptor binding assay and transmission electron microscopy, we observed that LPS binds to and alters the morphology of influenza virions, suggesting that direct interaction with the viral surface contributes to the observed antiviral effect of LPS on influenza. IMPORTANCE Influenza A virus (IAV), transmitted primarily via the fecal-oral route in wild birds, encounters high concentrations of bacteria and their products. Understanding the extent to which bacteria affect the infectivity of IAV will lead to a broader understanding of viral ecology in reservoir hosts and may lead to insights for the development of therapeutics in respiratory infection. Herein we show that bacteria and lipopolysaccharide (LPS) interact with and destabilize influenza virions. Moreover, we show that LPS reduces the long

High glucose-boosted inflammatory responses to lipopolysaccharide are suppressed by statin.

PubMed

Nareika, A; Maldonado, A; He, L; Game, B A; Slate, E H; Sanders, J J; London, S D; Lopes-Virella, M F; Huang, Y

2007-02-01

It has been established that periodontal diseases are more prevalent and of greater severity in diabetic patients than in nondiabetic patients. Recent studies have underscored the role of monocytes and macrophages in periodontal tissue inflammation and destruction in diabetic patients. Although it has been shown that monocytes isolated from diabetic patients produce more inflammatory cytokines and that gingival crevicular fluid collected from diabetic patients contains higher levels of inflammatory cytokines than that obtained from nondiabetic patients, the underlying mechanisms are not well understood. U937 histiocytes cultured in medium containing either normal (5 mM) or high (25 mM) glucose were treated with 100 ng/ml of lipopolysaccharide for 24h. After the treatment, cytokines in the medium and cytokine mRNA in the cells were quantified using enzyme-linked immunosorbet assay and real-time polymerase chain reaction, respectively. In this study, we demonstrated that the pre-exposure of U937 histiocytes to high glucose concentrations markedly increased the lipopolysaccharide-induced secretion of pro-inflammatory cytokines and chemokines and the cellular inducible nitric oxide level compared with pre-exposure to normal glucose. Our data also showed that the increased secretion of cytokines was a result of increased mRNA expression. Furthermore, the effects of statin and peroxisome proliferators-activated receptor agonists on high glucose-enhanced secretion of cytokines were determined. The results showed that simvastatin, but not fenofibrate or pioglitazone, inhibited high glucose-enhanced cytokine release. This study has shown that high glucose concentrations and lipopolysaccharide act synergistically to stimulate the secretion of inflammatory mediators, and that statin is capable of suppressing the high glucose-boosted proinflammatory response. This study therefore delineates a novel mechanism by which hyperglycemia enhances the inflammatory responses of

Effects of OPC-6535 on lipopolysaccharide-induced acute liver injury in the rat: involvement of superoxide and tumor necrosis factor-alpha from hepatic macrophages.

PubMed

Hasegawa, Tadashi; Sakurai, Kazushi; Kambayashi, Yasuhiro; Saniabadi, Abby R; Nagamoto, Hisashi; Tsukada, Katsuhiko; Takahashi, Atsushi; Kuwano, Hiroyuki; Nakano, Minoru

2003-11-01

The objective of this study was to investigate the effects of OPC-6535 on Propionibacterium acnes-primed and lipopolysaccharide-induced liver injury in the rat. P. acnes was administered intravenously to the rat at 16 mg/kg 7 days before the experiments. In liver perfusion experiments, lipopolysaccharide was mixed in perfusion buffer at 2.5 microg/mL. The chemiluminescence method and histochemical reduction of nitro blue tetrazolium were used for detecting superoxide. Release of cytokines into the perfusate was examined. In in vivo experiments, lipopolysaccharide was administered intravenously to the rat at 200 microg/kg. Concentrations of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and cytokines were determined in the plasma, and myeloperoxidase activity was measured in the liver tissue. OPC-6535 was given intravenously at 1 mg/kg 30 minutes before lipopolysaccharide challenge, and was then, in perfusion experiments, added to the buffer at 10 micromol/L. In perfusion experiments, P. acnes and lipopolysaccharide caused dramatic production of superoxide, tumor necrosis factor-alpha (TNF-alpha) and growth-related oncogene/cytokine-induced neutrophil chemoattractant-1 (GRO/CINC-1). Superoxide was mainly from hepatic macrophages. Treatment with OPC-6535 suppressed superoxide and TNF-alpha but did not affect GRO/CINC-1. In in vivo experiments, P. acnes and lipopolysaccharide increased the level of TNF-alpha, GRO/CINC-1, AST and ALT in the plasma, and myeloperoxidase activity in the liver. OPC-6535 reduced TNF-alpha, AST, and ALT, but did not affect GRO/CINC-1 or myeloperoxidase. Attenuation of liver injury by OPC-6535 is believed to be due to its inhibitory effects on superoxide and TNF-alpha production by hepatic macrophages in P. acnes- and lipopolysaccharide-treated rats.

Effect of Alkali-Treated Lipopolysaccharide on Erythrocyte Membrane Stability

PubMed Central

Čižnár, I.; Shands, J. W.

1971-01-01

The interaction of various lipopolysaccharides (LPS) with sheep erythrocytes was studied. When subjected to mild alkaline hydrolysis, the affinity of LPS for the red cell surface was greatly increased, as others have reported. In addition, excessive quantities of alkali-treated LPS (but not parent or heated products) were found to cause hemolysis of red cells. Experiments indicated that the hemolysis was caused by the LPS particles themselves and not by liberated free fatty acids. PMID:4949496

Lipopolysaccharide Membrane Building and Simulation

PubMed Central

Jo, Sunhwan; Wu, Emilia L.; Stuhlsatz, Danielle; Klauda, Jeffery B.; Widmalm, Göran; Im, Wonpil

2015-01-01

Summary While membrane simulations are widely employed to study the structure and dynamics of various lipid bilayers and membrane proteins in the bilayers, simulations of lipopolysaccharides (LPS) in membrane environments have been limited due to its structural complexity, difficulties in building LPS-membrane systems, and lack of appropriate molecular force field. In this work, as a first step to extend CHARMM-GUI Membrane Builder to incorporate LPS molecules and to explore their structures and dynamics in membrane environments using molecular dynamics simulations, we describe step-by-step procedures to build LPS bilayer systems using CHARMM and the recently developed CHARMM carbohydrate and lipid force fields. Such procedures are illustrated by building various bilayers of Escherichia coli O6 LPS and their preliminary simulation results are given in terms of per-LPS area and density distributions of various components along the membrane normal. PMID:25753722

The Antibiotic Novobiocin Binds and Activates the ATPase That Powers Lipopolysaccharide Transport.

PubMed

May, Janine M; Owens, Tristan W; Mandler, Michael D; Simpson, Brent W; Lazarus, Michael B; Sherman, David J; Davis, Rebecca M; Okuda, Suguru; Massefski, Walter; Ruiz, Natividad; Kahne, Daniel

2017-12-06

Novobiocin is an orally active antibiotic that inhibits DNA gyrase by binding the ATP-binding site in the ATPase subunit. Although effective against Gram-positive pathogens, novobiocin has limited activity against Gram-negative organisms due to the presence of the lipopolysaccharide-containing outer membrane, which acts as a permeability barrier. Using a novobiocin-sensitive Escherichia coli strain with a leaky outer membrane, we identified a mutant with increased resistance to novobiocin. Unexpectedly, the mutation that increases novobiocin resistance was not found to alter gyrase, but the ATPase that powers lipopolysaccharide (LPS) transport. Co-crystal structures, biochemical, and genetic evidence show novobiocin directly binds this ATPase. Novobiocin does not bind the ATP binding site but rather the interface between the ATPase subunits and the transmembrane subunits of the LPS transporter. This interaction increases the activity of the LPS transporter, which in turn alters the permeability of the outer membrane. We propose that novobiocin will be a useful tool for understanding how ATP hydrolysis is coupled to LPS transport.

Decreased neuronal CD200 expression in IL-4-deficient mice results in increased neuroinflammation in response to lipopolysaccharide.

PubMed

Lyons, Anthony; McQuillan, Keith; Deighan, Brian F; O'Reilly, Julie-Ann; Downer, Eric J; Murphy, Aine C; Watson, Melanie; Piazza, Alessia; O'Connell, Florence; Griffin, Rebecca; Mills, Kingston H G; Lynch, Marina A

2009-10-01

Maintenance of the balance between pro- and anti-inflammatory cytokines in the brain, which is affected by the activation state of microglia, is important for maintenance of neuronal function. Evidence has suggested that IL-4 plays an important neuromodulatory role and has the ability to decrease lipopolysaccharide-induced microglial activation and the production of IL-1beta. We have also demonstrated that CD200-CD200R interaction is involved in immune homeostasis in the brain. Here, we investigated the anti-inflammatory role of IL-4 and, using in vitro and in vivo analysis, established that the effect of lipopolysaccharide was more profound in IL-4(-/-), compared with wildtype, mice. Intraperitoneal injection of lipopolysaccharide exerted a greater inhibitory effect on exploratory behaviour in IL-4(-/-), compared with wildtype, mice and this was associated with evidence of microglial activation. We demonstrate that the increase in microglial activation is inversely related to CD200 expression. Furthermore, CD200 was decreased in neurons prepared from IL-4(-/-) mice, whereas stimulation with IL-4 enhanced CD200 expression. Importantly, neurons prepared from wildtype, but not from IL-4(-/-), mice attenuated the lipopolysaccharide-induced increase in pro-inflammatory cytokine production by glia. These findings suggest that the neuromodulatory effect of IL-4, and in particular its capacity to maintain microglia in a quiescent state, may result from its ability to upregulate CD200 expression on neurons.

Structure and functional analysis of LptC, a conserved membrane protein involved in the lipopolysaccharide export pathway in Escherichia coli.

PubMed

Tran, An X; Dong, Changjiang; Whitfield, Chris

2010-10-22

LptC is a conserved bitopic inner membrane protein from Escherichia coli involved in the export of lipopolysaccharide from its site of synthesis in the cytoplasmic membrane to the outer membrane. LptC forms a complex with the ATP-binding cassette transporter, LptBFG, which is thought to facilitate the extraction of lipopolysaccharide from the inner membrane and release it into a translocation pathway that includes the putative periplasmic chaperone LptA. Cysteine modification experiments established that the catalytic domain of LptC is oriented toward the periplasm. The structure of the periplasmic domain is described at a resolution of 2.2-Å from x-ray crystallographic data. The periplasmic domain of LptC consists of a twisted boat structure with two β-sheets in apposition to each other. The β-sheets contain seven and eight antiparallel β-strands, respectively. This structure bears a high degree of resemblance to the crystal structure of LptA. Like LptA, LptC binds lipopolysaccharide in vitro. In vitro, LptA can displace lipopolysaccharide from LptC (but not vice versa), consistent with their locations and their proposed placement in a unidirectional export pathway.

Structural studies of the O-specific polysaccharide(s) from the lipopolysaccharide of Azospirillum brasilense type strain Sp7.

PubMed

Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

2013-10-18

Lipopolysaccharide was obtained by phenol-water extraction from dried bacterial cells of Azospirillum brasilense type strain Sp7. Mild acid hydrolysis of the lipopolysaccharide followed by GPC on Sephadex G-50 resulted in a polysaccharide mixture, which was studied by composition and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy. The following polysaccharide structures were established, where italics indicate a non-stoichiometric (∼40%) 2-O-methylation of l-rhamnose. Copyright © 2013 Elsevier Ltd. All rights reserved.

Exposure to lipopolysaccharide in utero alters the postnatal metabolic response in heifers

USDA-ARS?s Scientific Manuscript database

This study was designed to determine the effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal metabolic response to an LPS challenge in beef heifers. Pregnant crossbred cows (n = 50) were assigned to a prenatal immune stimulation (PIS; n = 25; administered 0.1 micrograms/kg BW LPS s...

MiR-146a activates WAVE2 expression and enhances phagocytosis in lipopolysaccharide-stimulated RAW264.7 macrophages

PubMed Central

Cao, Zhongwei; Yao, Qunyan; Zhang, Shuncai

2015-01-01

MiR-146a has been shown to play a critical role in cell immunity and phagocytosis, processes that require rearrangement of the cytoskeleton. However, the detailed mechanism by which miR-146a regulates these events remains elusive. Here, we used luciferase reporter and protein assays to show that the cytoskeleton-regulatingprotein verprolin-homologous protein 2 (WAVE2), is a direct target of miR-146a. MiR-146a overexpression resulted in a decrease in WAVE2 protein expression under endotoxin-free culture conditions. Unexpectedly, however, miR-146a activated rather than repressed the expression of WAVE2 in macrophage RAW264.7 cells when cultured continuously in the presence of endotoxin. Furthermore, we demonstrated that miR-146a induced WAVE2 expression and enhanced phagocytosis in lipopolysaccharide-stimulated RAW264.7 macrophages. Our study suggests that lipopolysaccharide- induced miR146a indirectly activates WAVE2 expression; thus, facilitating cytoskeletal reorganization and phagocytosis in lipopolysaccharide-stimulated macrophages. PMID:26396677

MiR-146a activates WAVE2 expression and enhances phagocytosis in lipopolysaccharide-stimulated RAW264.7 macrophages.

PubMed

Cao, Zhongwei; Yao, Qunyan; Zhang, Shuncai

2015-01-01

MiR-146a has been shown to play a critical role in cell immunity and phagocytosis, processes that require rearrangement of the cytoskeleton. However, the detailed mechanism by which miR-146a regulates these events remains elusive. Here, we used luciferase reporter and protein assays to show that the cytoskeleton-regulatingprotein verprolin-homologous protein 2 (WAVE2), is a direct target of miR-146a. MiR-146a overexpression resulted in a decrease in WAVE2 protein expression under endotoxin-free culture conditions. Unexpectedly, however, miR-146a activated rather than repressed the expression of WAVE2 in macrophage RAW264.7 cells when cultured continuously in the presence of endotoxin. Furthermore, we demonstrated that miR-146a induced WAVE2 expression and enhanced phagocytosis in lipopolysaccharide-stimulated RAW264.7 macrophages. Our study suggests that lipopolysaccharide- induced miR146a indirectly activates WAVE2 expression; thus, facilitating cytoskeletal reorganization and phagocytosis in lipopolysaccharide-stimulated macrophages.

Structural studies on lipopolysaccharides of serologically non-typable strains of Helicobacter pylori, AF1 and 007, expressing Lewis antigenic determinants.

PubMed

Knirel, Y A; Kocharova, N A; Hynes, S O; Widmalm, G; Andersen, L P; Jansson, P E; Moran, A P

1999-11-01

In contrast to other Helicobacter pylori strains, which have serologically detectable Lewis(x)+ (Le(x)) and Lewis(y)++ (++Le(y)) antigenic determinants in the O-specific polysaccharide chains of the lipopolysaccharides, H. pylori AF1 and 007 were non-typable with anti-Le(x) and anti-Le(y) antibodies. The carbohydrate portions of the lipopolysaccharides were liberated by mild acid hydrolysis and subsequently studied by sugar and methylation analyses, 1H-NMR spectroscopy and electrospray ionization-mass spectrometry. Compared with each other, and with lipopolysaccharides of strains studied previously, the lipopolysaccharides of both AF1 and 007 showed similarities, but also differences, in the structures of the core region and O-specific polysaccharide chains. The O-specific polysaccharide chains of both strains consisted of a short or long polyfucosylated poly-N-acetyl-beta-lactosamine chains, which were distinguished from those of other strains by a high degree of fucosylation producing a polymeric Le(x)chain terminating with Le(x) or Le(y) units:[sequence: see text] where n = 0 or 1 in strain AF1 and 0 in strain 007, m = 0-2, 6-7 in strain AF1 and m = 0-2, 6-7 or approximately 40 in strain 007, the medium-size species being predominant. Therefore, compared with other strains, the lack of reactivity of lipopolysaccharide of H. pylori AF1 and 007 with anti-Le(x) and anti-Le(y) may reflect the presence of a polymeric Le(x) chain and has important implications for serological and pathogenesis studies. As the substitution pattern of a D-glycero-D-manno-heptose residue in the outer core varied in the two strains, and an extended DD-heptan chain was present in some lipopolysaccharide species but not in others, this region was less conservative than the inner core region. The inner core L-glycero-D-manno-heptose region of both strains carried a 2-aminoethyl phosphate group, rather than a phosphate group, as reported previously for other H. pylori strains.

An antibacterial vaccination strategy based on a glycoconjugate containing the core lipopolysaccharide tetrasaccharide Hep2Kdo2

NASA Astrophysics Data System (ADS)

Kong, Lingbing; Vijayakrishnan, Balakumar; Kowarik, Michael; Park, Jin; Zakharova, Alexandra N.; Neiwert, Larissa; Faridmoayer, Amirreza; Davis, Benjamin G.

2016-03-01

Certain non-mammalian cell wall sugars are conserved across a variety of pathogenic bacteria. This conservation of structure, combined with their structural differences when compared with mammalian sugars, make them potentially powerful epitopes for immunization. Here, we report the synthesis of a glycoconjugate that displays the so-called ‘inner core’ sugars of Gram-negative bacterial cell walls. We also describe an antibacterial vaccination strategy based on immunization with the glycoconjugate and the subsequent administration of an inhibitor that uncovers the corresponding epitope in pathogenic bacteria. The core tetrasaccharide, Hep2Kdo2, a common motif in bacterial lipopolysaccharides, was synthesized and attached via a chain linker to a diphtheria toxin mutant carrier protein. This glycoconjugate generated titres of antibodies towards the inner core tetrasaccharide of the lipopolysaccharide, which were capable of binding the cell-surface sugars of bacterial pathogenic strains including Neisseria meningitidis, Pseudomonas aeruginosa and Escherichia coli. Exposure of bacterial lipopolysaccharide in in vitro experiments, using an inhibitor of capsular polysaccharide transport, enabled potent bacterial killing with antiserum.

Sensitive assay, based on hydroxy fatty acids from lipopolysaccharide lipid A, for Gram-negative bacteria in sediments.

PubMed Central

Parker, J H; Smith, G A; Fredrickson, H L; Vestal, J R; White, D C

1982-01-01

Biochemical measures have provided insight into the biomass and community structure of sedimentary microbiota without the requirement of selection by growth or quantitative removal from the sediment grains. This study used the assay of the hydroxy fatty acids released from the lipid A of the lipopolysaccharide in sediments to provide an estimate of the gram-negative bacteria. The method was sensitive to picomolar amounts of hydroxy fatty acids. The recovery of lipopolysaccharide hydroxy fatty acids from organisms added to sediments was quantitative. The lipids were extracted from the sediments with single-phase chloroform-methanol extraction. The lipid-extraction residue was hydrolyzed in 1 N HCl, and the hydroxy fatty acids of the lipopolysaccharide were recovered in chloroform for analysis by gas-liquid chromatography. This method proved to be about fivefold more sensitive than the classical phenol-water or trichloroacetic acid methods when applied to marine sediments. By examination of the patterns of hydroxy fatty acids, it was also possible to help define the community structure of the sedimentary gram-negative bacteria. PMID:6817712

Doxycycline Attenuates Lipopolysaccharide-Induced Microvascular Endothelial Cell Derangements.

PubMed

Wiggins-Dohlvik, Katie; Stagg, Hayden W; Han, Min Suk; Alluri, Himakarnika; Oakley, Ryan P; Anasooya Shaji, Chinchusha; Davis, Matthew L; Tharakan, Binu

2016-06-01

Lipopolysaccharide (LPS) is known to induce vascular derangements. The pathophysiology involved therein is unknown, but matrix metalloproteinases (MMPs) may be an important mediator. We hypothesized that in vitro LPS provokes vascular permeability, damages endothelial structural proteins, and increases MMP activity; that in vivo LPS increases permeability and fluid requirements; and that the MMP inhibitor doxycycline mitigates such changes. Rat lung microvascular endothelial cells were divided into four groups: control, LPS, LPS plus doxycycline, and doxycycline. Permeability, structural proteins β-catenin and Filamentous-actin, and MMP-9 activity were examined. Sprauge Dawley rats were divided into sham, IV LPS, and IV LPS plus IV doxycycline groups. Mesenteric postcapillary venules were observed. Blood pressure was measured as animals were resuscitated and fluid requirements were compared. Statistical analysis was conducted using Student's t-test and ANOVA. In vitro LPS increased permeability, damaged adherens junctions, induced actin stress fiber formation, and increased MMP-9 enzyme activity. In vivo, IV LPS administration induced vascular permeability. During resuscitation, significantly more fluid was necessary to maintain normotension in the IV LPS group. Doxycycline mitigated all derangements observed. We conclude that LPS increases permeability, damages structural proteins, and increases MMP-9 activity in endothelial cells. Additionally, endotoxemia induces hyperpermeability and increases the amount of IV fluid required to maintain normotension in vivo. Doxycycline mitigates such changes both in vitro and in vivo. Our findings illuminate the possible role of matrix metalloproteinases in the pathophysiology of lipopolysaccharide-induced microvascular hyperpermeability and pave the way for better understanding and treatment of this process.

Alpha-lipoic acid protects mitochondrial enzymes and attenuates lipopolysaccharide-induced hypothermia in mice

EPA Science Inventory

Abstract: Hypothermia is a key symptom of sepsis and the mechanism(s) leading to hypothermia during sepsis is largely unknown. To investigate a potential mechanism and find an effective treatment for hypothermia in sepsis, we induced hypothermia in mice by lipopolysaccharide (LP...

The role of lipopolysaccharide on the electrochemical behavior of titanium.

PubMed

Barão, V A; Mathew, M T; Assunção, W G; Yuan, J C; Wimmer, M A; Sukotjo, C

2011-05-01

Lipopolysaccharide (LPS) may induce peri-implantitis and implant failure. However, the role of LPS in titanium (Ti) electrochemical behavior remains unknown. We hypothesized that LPS in saliva with different pHs affects Ti corrosion properties. Thirty-six Ti discs (15 mm × 3 mm) were divided into 12 groups according to saliva pH (3, 6.5, and 9) and Escherichia coli LPS concentration (0, 0.15, 15, and 150 µg/mL). Electrochemical tests, such as open circuit potential, potentiodynamic, and electrochemical impedance spectroscopy, were conducted in a controlled environment. Data were evaluated by Pearson correlation and regression analysis (α = 0.05). LPS and pH affected Ti corrosive behavior. In general, lower pH and higher LPS concentration accelerated Ti corrosion. In the control group, the increase of pH significantly reduced the corrosion rate and increased the capacitance of the double layer. In LPS groups, the decrease of pH significantly increased the corrosion rate of Ti. LPS negatively influenced Ti corrosion behavior. C(dl), capacitance of double layer; E(corr), corrosion potential; EIS, electrochemical impedance spectroscopy; I(corr), corrosion current density; I(pass), passivation current density; LPS, lipopolysaccharide; OCP, open circuit potential; R(p), polarization resistance; Ti, titanium.

Dietary L-arginine supplementation modulates lipopolysaccharide-induced systemic inflammatory response in broiler chickens

USDA-ARS?s Scientific Manuscript database

This study was conducted to evaluate whether dietary supplementation with L-arginine (Arg) could attenuate lipopolysaccharide (LPS)-induced systemic inflammatory response through LPS/TLR-4 signaling pathway in broilers. The experiment was designed as a 2 × 3 factorial arrangement (n = 8 cages/treatm...

Lipopolysaccharides in diazotrophic bacteria.

PubMed

Serrato, Rodrigo V

2014-01-01

Biological nitrogen fixation (BNF) is a process in which the atmospheric nitrogen (N2) is transformed into ammonia (NH3) by a select group of nitrogen-fixing organisms, or diazotrophic bacteria. In order to furnish the biologically useful nitrogen to plants, these bacteria must be in constant molecular communication with their host plants. Some of these molecular plant-microbe interactions are very specific, resulting in a symbiotic relationship between the diazotroph and the host. Others are found between associative diazotrophs and plants, resulting in plant infection and colonization of internal tissues. Independent of the type of ecological interaction, glycans, and glycoconjugates produced by these bacteria play an important role in the molecular communication prior and during colonization. Even though exopolysaccharides (EPS) and lipochitooligosaccharides (LCO) produced by diazotrophic bacteria and released onto the environment have their importance in the microbe-plant interaction, it is the lipopolysaccharides (LPS), anchored on the external membrane of these bacteria, that mediates the direct contact of the diazotroph with the host cells. These molecules are extremely variable among the several species of nitrogen fixing-bacteria, and there are evidences of the mechanisms of infection being closely related to their structure.

Lipopolysaccharides in diazotrophic bacteria

PubMed Central

Serrato, Rodrigo V.

2014-01-01

Biological nitrogen fixation (BNF) is a process in which the atmospheric nitrogen (N2) is transformed into ammonia (NH3) by a select group of nitrogen-fixing organisms, or diazotrophic bacteria. In order to furnish the biologically useful nitrogen to plants, these bacteria must be in constant molecular communication with their host plants. Some of these molecular plant-microbe interactions are very specific, resulting in a symbiotic relationship between the diazotroph and the host. Others are found between associative diazotrophs and plants, resulting in plant infection and colonization of internal tissues. Independent of the type of ecological interaction, glycans, and glycoconjugates produced by these bacteria play an important role in the molecular communication prior and during colonization. Even though exopolysaccharides (EPS) and lipochitooligosaccharides (LCO) produced by diazotrophic bacteria and released onto the environment have their importance in the microbe-plant interaction, it is the lipopolysaccharides (LPS), anchored on the external membrane of these bacteria, that mediates the direct contact of the diazotroph with the host cells. These molecules are extremely variable among the several species of nitrogen fixing-bacteria, and there are evidences of the mechanisms of infection being closely related to their structure. PMID:25232535

The role of lipopolysaccharide in infectious bone resorption of periapical lesion.

PubMed

Hong, Chi-Yuan; Lin, Sze-Kwan; Kok, Sang-Heng; Cheng, Shih-Jung; Lee, Ming-Shu; Wang, Tong-Mei; Chen, Chuan-Shuo; Lin, Li-Deh; Wang, Juo-Song

2004-03-01

The role of lipopolysaccharide (LPS) in periapical lesion-induced bone resorption was investigated. Polymyxin B (PMB), a specific inhibitor of LPS, was evaluated to treat the apical lesion. Lipopolysaccharide isolated from two common endodontic pathogens, Fusobacterium nucleatum and Porphyromonas endodontalis, stimulated mouse macrophage (J774) to release interleukin-1alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) in a time-dependent manner. Combination of LPS further enhanced the stimulation. PMB inhibited these effects significantly. LPS also stimulated matrix metalloproteinase-1 (MMP-1) gene expression in J774, whereas anti-IL-1 alpha and anti-TNF-alpha antibodies, as well as PMB, diminished this effect. A disease model of periapical lesion was established in Wistar rat. Administration of PMB reduced the extent of lesion-associated bone resorption by 76% to approximately 80%, and simultaneously reduced the numbers of MMP-1-producing macrophages. It is suggested that LPS released from the infected root canal triggers the synthesis of IL-1 alpha and TNF-alpha from macrophages. These pro-inflammatory cytokines up-regulate the production of MMP-1 by macrophages to promote periapical bone resorption.

Structural basis for lipopolysaccharide extraction by ABC transporter LptB2FG.

PubMed

Luo, Qingshan; Yang, Xu; Yu, Shan; Shi, Huigang; Wang, Kun; Xiao, Le; Zhu, Guangyu; Sun, Chuanqi; Li, Tingting; Li, Dianfan; Zhang, Xinzheng; Zhou, Min; Huang, Yihua

2017-05-01

After biosynthesis, bacterial lipopolysaccharides (LPS) are transiently anchored to the outer leaflet of the inner membrane (IM). The ATP-binding cassette (ABC) transporter LptB 2 FG extracts LPS molecules from the IM and transports them to the outer membrane. Here we report the crystal structure of nucleotide-free LptB 2 FG from Pseudomonas aeruginosa. The structure reveals that lipopolysaccharide transport proteins LptF and LptG each contain a transmembrane domain (TMD), a periplasmic β-jellyroll-like domain and a coupling helix that interacts with LptB on the cytoplasmic side. The LptF and LptG TMDs form a large outward-facing V-shaped cavity in the IM. Mutational analyses suggest that LPS may enter the central cavity laterally, via the interface of the TMD domains of LptF and LptG, and is expelled into the β-jellyroll-like domains upon ATP binding and hydrolysis by LptB. These studies suggest a mechanism for LPS extraction by LptB 2 FG that is distinct from those of classical ABC transporters that transport substrates across the IM.

In Vitro Antimicrobial and Antiproliferative Activity of Amphipterygium adstringens

PubMed Central

Rodriguez-Garcia, A.; Peixoto, I. T. A.; Verde-Star, M. J.; De la Torre-Zavala, S.; Aviles-Arnaut, H.; Ruiz, A. L. T. G.

2015-01-01

Amphipterygium adstringens is a plant widely used in Mexican traditional medicine for its known anti-inflammatory and antiulcer properties. In this work, we evaluated the in vitro antimicrobial and antiproliferative activities of the methanolic extract of A. adstringens against oral pathogens such as Streptococcus mutans, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Candida albicans, and Candida dubliniensis, using microdilution (MIC) and agar diffusion methods (MBC), and the antiproliferative activity evaluating total growth inhibition (TGI) by staining the protein content with sulforhodamine B (SRB), using nine human cancer cell lines. Crude extract (CE) of A. adstringens showed some degree of activity against one or more of the strains with a MIC from 0.125 mg/mL to 63 mg/mL and MBC from 1.6 to 6.3 mg/mL and cytotoxic activity, particularly against NCI-ADR/RES, an ovarian cell line expressing multiple resistance drugs phenotype. The CE is a complex mixture of possible multitarget metabolites that could be responsible for both antimicrobial and antiproliferative activities, and further investigation is required to elucidate the identity of active compounds. Nevertheless the CE itself is useful in the development of new antimicrobial treatment based on natural products to prevent oral diseases and as alternative natural source for cancer treatment and prevention. PMID:26451151

A 6-month study of the effects of 0.3% triclosan/copolymer dentifrice on dental implants.

PubMed

Sreenivasan, Prem K; Vered, Yuval; Zini, Avi; Mann, Jonathan; Kolog, Hilla; Steinberg, Doron; Zambon, Joseph J; Haraszthy, Violet I; da Silva, Maike P; De Vizio, William

2011-01-01

Supportive therapy to maintain dental implants is increasingly important. This study examined the effect of a 0.3% triclosan/2% copolymer dentifrice on oral biofilms and gingival inflammation (GI) on dental implants and peri-implant tissues. One hundred and twenty adults with a dental implant and contra-lateral tooth were enrolled in this 6 month, double-blind, two-treatment, parallel group study. Sixty subjects were randomly assigned to a triclosan/copolymer dentifrice test group and 60 subjects to a fluoride dentifrice control group and instructed to brush twice daily for 6 months. At baseline, 3, and 6 months, a calibrated dentist assessed dental plaque, GI and collected supragingival dental plaque for microbiological analysis. Subjects in the triclosan/copolymer group demonstrated significantly lower levels of dental plaque, gingivitis, and bleeding on probing at 3 and 6 months at both the implant and contra-lateral tooth compared with the fluoride group (p<0.05). There were significantly fewer Gram-negative anaerobes in the triclosan/copolymer group (p<0.05) including >90% reductions in Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Eubacterium saburreum, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella melaninogenica, Solobacterium moorei, and Tannerella forsythia. Twice daily use of a triclosan/copolymer dentifrice may enhance dental implant maintenance by reducing dental plaque and GI. © 2010 John Wiley & Sons A/S.

Laser supported reduction of specific microorganisms in the periodontal pocket with the aid of an Er,Cr:YSGG laser: a pilot study.

PubMed

Gutknecht, N; Van Betteray, C; Ozturan, S; Vanweersch, L; Franzen, R

2015-01-01

The aim of this study was to evaluate the effectiveness of a radial firing tip of an Er,Cr:YSGG laser as an adjunct to a nonsurgical periodontal treatment. Twelve patients with chronic or aggressive periodontitis were treated by conventional periodontal treatment using ultrasonic devices and hand instruments and, additionally, in two quadrants with an Er,Cr:YSGG laser. A new radial firing tip (RFPT 14-5, Biolase) was used with 1.5 W, 30 Hz, 11% air, 20% water, and pulse duration 140 μs. Microbiological smears were taken before treatment, one day after lasing, and three and six months after lasing. Pocket depths of all periodontal sites were measured before and six months after treatment. The total bacterial load of Prevotella intermedia, Tannerella forsythia, Treponema denticola, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans inside the pocket was reduced significantly throughout the whole examination time. Greater pocket depth reductions were observed in all groups. There was a slight higher reduction of pocket depth in the lased group after six months. These results support the thesis that Er,Cr:YSGG laser supported periodontal treatment leads to a significant reduction of periopathogenes and thereby helps the maintenance of periodontal health.

Anti-leukemia activity of a bacterial toxin with natural specificity for LFA-1 on white blood cells

PubMed Central

Kachlany, Scott C.; Schwartz, Amy B.; Balashova, Nataliya V.; Hioe, Catarina E.; Tuen, Michael; Le, Amy; Kaur, Manpreet; Mei, Yongyi; Rao, Jia

2009-01-01

The oral bacterium, Aggregatibacter actinomycetemcomitans, produces a leukotoxin (LtxA) that is specific for white blood cells (WBCs) from humans and Old World primates by interacting with lymphocyte function antigen-1 (LFA-1) on susceptible cells. To determine if LtxA could be used as a therapeutic agent for the treatment of WBC diseases, we tested the in vitro and in vivo anti-leukemia activity of the toxin. LtxA kills human malignant WBC lines and primary leukemia cells from acute myeloid leukemia patients, but healthy peripheral blood mononuclear cells (PBMCs) are relatively resistant to LtxA-mediated cytotoxicity. Levels of LFA-1 on cell lines correlated with killing by LtxA and the toxin preferentially killed cells expressing the activated form of LFA-1. In a SCID mouse model for human leukemia, LtxA had potent therapeutic value resulting in long-term survival in LtxA-treated mice. Intravenous infusion of LtxA into a rhesus macaque resulted in a drop in WBC counts at early times post-infusion; however, red blood cells, platelets, hemoglobin and blood chemistry values remained unaffected. Thus, LtxA may be an effective and safe novel therapeutic agent for the treatment of hematologic malignancies. PMID:19747730

Total Antioxidant Capacity and Total Oxidant Status in Saliva of Periodontitis Patients in Relation to Bacterial Load

PubMed Central

Zhang, Taowen; Andrukhov, Oleh; Haririan, Hady; Müller-Kern, Michael; Liu, Shutai; Liu, Zhonghao; Rausch-Fan, Xiaohui

2016-01-01

The detection of salivary biomarkers has a potential application in early diagnosis and monitoring of periodontal inflammation. However, searching sensitive salivary biomarkers for periodontitis is still ongoing. Oxidative stress is supposed to play an important role in periodontitis progression and tissue destruction. In this cross-sectional study, we investigated total antioxidant capacity (TAC) and total oxidant status (TOS) in saliva of periodontitis patients compared to healthy controls and their relationship with periodontopathic bacteria and periodontal disease severity. Unstimulated saliva was collected from 45 patients with generalized severe periodontitis and 37 healthy individuals and the TAC/TOS were measured. In addition, salivary levels of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum in saliva were measured. Salivary TAC was lower in periodontitis patients compared to healthy controls. Moreover, a significant negative correlation of salivary TAC with clinical attachment loss was observed in periodontitis patients. No significant difference in the salivary TOS was observed between periodontitis patients and healthy controls. Bacterial load was enhanced in periodontitis patients and exhibited correlation with periodontal disease severity but not with salivary TAC/TOS. Our data suggest that changes in antioxidant capacity in periodontitis patients are not associated with increased bacterial load and are probably due to a dysregulated immune response. PMID:26779448

Porphyromonas gingivalis Fim-A genotype distribution among Colombians

PubMed Central

Jaramillo, Adriana; Parra, Beatriz; Botero, Javier Enrique; Contreras, Adolfo

2015-01-01

Introduction: Porphyromonas gingivalis is associated with periodontitis and exhibit a wide array of virulence factors, including fimbriae which is encoded by the FimA gene representing six known genotypes. Objetive: To identify FimA genotypes of P. gingivalis in subjects from Cali-Colombia, including the co-infection with Aggregatibacter actinomycetemcomitans, Treponema denticola, and Tannerella forsythia. Methods: Subgingival samples were collected from 151 people exhibiting diverse periodontal condition. The occurrence of P. gingivalis, FimA genotypes and other bacteria was determined by PCR. Results: P. gingivalis was positive in 85 patients. Genotype FimA II was more prevalent without reach significant differences among study groups (54.3%), FimA IV was also prevalent in gingivitis (13.0%). A high correlation (p= 0.000) was found among P. gingivalis, T. denticola, and T. forsythia co-infection. The FimA II genotype correlated with concomitant detection of T. denticola and T. forsythia. Conclusions: Porphyromonas gingivalis was high even in the healthy group at the study population. A trend toward a greater frequency of FimA II genotype in patients with moderate and severe periodontitis was determined. The FimA II genotype was also associated with increased pocket depth, greater loss of attachment level, and patients co-infected with T. denticola and T. forsythia. PMID:26600627

Oxidative Stress Parameters in Saliva and Its Association with Periodontal Disease and Types of Bacteria.

PubMed

Almerich-Silla, Jose Manuel; Montiel-Company, Jose María; Pastor, Sara; Serrano, Felipe; Puig-Silla, Miriam; Dasí, Francisco

2015-01-01

To determine the association between oxidative stress parameters with periodontal disease, bleeding, and the presence of different periodontal bacteria. A cross-sectional study in a sample of eighty-six patients, divided into three groups depending on their periodontal status. Thirty-three with chronic periodontitis, sixteen with gingivitis, and thirty-seven with periodontal healthy as control. Oxidative stress biomarkers (8-OHdG and MDA), total antioxidant capacity (TAOC), and the activity of two antioxidant enzymes (GPx and SOD) were determined in saliva. Subgingival plaque samples were obtained from the deepest periodontal pocket and PCR was used to determine the presence of the 6 fimA genotypes of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, and Treponema denticola. Periodontal disease was found to be associated with increased oxidative stress parameter levels. These levels rose according to the number and type of different periodontal bacteria found in the periodontal pockets. The presence of different types of periodontal bacteria is predictive independent variables in linear regresion models of oxidative stress parameters as dependent variable, above all 8-OHdG. Oxidative stress parameter levels are correlated with the presence of different types of bacteria. Determination of these levels and periodontal bacteria could be a potent tool for controlling periodontal disease development.

Effect of lipopolysaccharide on sickness behaviour in hens kept in cage and free range environments.

PubMed

Gregory, N G; Payne, S R; Devine, C D; Cook, C J

2009-08-01

The aim of this study was to assess whether environmental enrichment and environmental conditions can influence the expression of sickness behaviour. The behaviour in response to injection of lipopolysaccharide or saline was examined in a total of 96 62-weeks old hatchmate hens kept in a free range or cage environment. There were eight experimental treatments, each with 12 birds. Half the birds were sourced from a commercial cage layer unit (C/-) and half from a commercial free range unit (FR/-). After intraperitoneal injection with either lipopolysaccharide or saline (as a control), the hens were placed in either a cage (-/C) or free range (-/FR) environment. Lipopolysaccharide caused greater suppression of activity in free range (FR/FR) than in caged hens, including less walking (53% reduction), roosting (-86%) and preening (-60%) (p<0.05). Those responses were not observed in caged birds released into free range, nor in free range birds introduced to cages, suggesting that both the presence of and the familiarity with an environment affected sickness behaviour patterns. Increased sleeping was the most consistent response (+147%; p<0.001), and it was least influenced by environment. It was concluded that free range layer hens can express a greater range of sickness behaviours than caged hens, and this may make it more difficult to recognise disease expression in the caged environment.

Tissue- and cell-specific expression of mouse xanthine oxidoreductase gene in vivo: regulation by bacterial lipopolysaccharide.

PubMed Central

Kurosaki, M; Li Calzi, M; Scanziani, E; Garattini, E; Terao, M

1995-01-01

The expression of the xanthine oxidoreductase gene was studied in various mouse organs and tissues, under basal conditions and on treatment with bacterial lipopolysaccharide. Levels of xanthine oxidoreductase protein and mRNA were compared in order to understand the molecular mechanisms regulating the expression of this enzyme system. The highest amounts of xanthine oxidoreductase and the respective mRNA are observed in the duodenum and jejunum, where the protein is present in an unusual form because of a specific proteolytic cleavage of the primary translation product present in all locations. Under basal conditions, multiple tissue-specific mechanisms of xanthine oxidoreductase regulation are evident. Lipopolysaccharide increases enzyme activity in some, but not all tissues, mainly via modulation of the respective transcript, although translational and post-translational mechanisms are also active. In situ hybridization studies on tissue sections obtained from mice under control conditions or with lipopolysaccharide treatment demonstrate that xanthine oxidoreductase is present in hepatocytes, predominantly in the proximal tubules of the kidney, epithelial layer of the gastrointestinal mucosa, the alveolar compartment of the lung, the pulpar region of the spleen and the vascular component of the heart. Images Figure 1 Figure 2 Figure 4 Figure 5 Figure 6 PMID:7864814

Use of Monoclonal Antibodies to Lipopolysaccharide for Antigenic Analysis of Coxiella burnetii

PubMed Central

Hotta, Akitoyo; Kawamura, Midori; To, Ho; Andoh, Masako; Yamaguchi, Tsuyoshi; Fukushi, Hideto; Amano, Ken-Ichi; Hirai, Katsuya

2003-01-01

Antigenic differences among Coxiella burnetii strains were analyzed. The monoclonal antibodies against the lipopolysaccharide outer core did not react with the strains containing a QpRS plasmid or with plasmidless strains, whereas they reacted with strains containing a QpH1 or QpDV plasmid. C. burnetii isolates could be divided into two groups immunologically. PMID:12682176

Periodontal Bacteria and Prediabetes Prevalence in ORIGINS

PubMed Central

Demmer, R.T.; Jacobs, D.R.; Singh, R.; Zuk, A.; Rosenbaum, M.; Papapanou, P.N.; Desvarieux, M.

2015-01-01

Periodontitis and type 2 diabetes mellitus are known to be associated. The relationship between periodontal microbiota and early diabetes risk has not been studied. We investigated the association between periodontal bacteria and prediabetes prevalence among diabetes-free adults. ORIGINS (the Oral Infections, Glucose Intolerance and Insulin Resistance Study) cross sectionally enrolled 300 diabetes-free adults aged 20 to 55 y (mean ± SD, 34 ± 10 y; 77% female). Prediabetes was defined as follows: 1) hemoglobin A1c values ranging from 5.7% to 6.4% or 2) fasting plasma glucose ranging from 100 to 125 mg/dL. In 1,188 subgingival plaque samples, 11 bacterial species were assessed at baseline, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Actinomyces naeslundii. Full-mouth clinical periodontal examinations were performed, and participants were defined as having no/mild periodontitis vs. moderate/severe periodontitis per the definition of the Centers for Disease Control and Prevention / American Academy of Periodontology. Modified Poisson regression evaluated prediabetes prevalence across bacterial tertiles. Prevalence ratios and 95% confidence intervals for third vs. first tertiles are presented. All analyses were adjusted for cardiometabolic risk factors. All results presented currently arise from the baseline cross section. Prediabetes prevalence was 18%, and 58% of participants had moderate/severe periodontitis. Prevalence ratios (95% confidence intervals) summarizing associations between bacterial levels and prediabetes were as follows: A. actinomycetemcomitans, 2.48 (1.34, 4.58), P = 0.004; P. gingivalis, 3.41 (1.78, 6.58), P = 0.0003; T. denticola, 1.99 (0.992, 4.00), P = 0.052; T. forsythia, 1.95 (1.0, 3.84), P = 0.05; A. naeslundii, 0.46 (0.25, 0.85), P = 0.01. The prevalence ratio for prediabetes among participants with moderate/severe vs. no/mild periodontitis was 1.47 (0.78, 2.74), P

Periodontal Bacteria and Prediabetes Prevalence in ORIGINS: The Oral Infections, Glucose Intolerance, and Insulin Resistance Study.

PubMed

Demmer, R T; Jacobs, D R; Singh, R; Zuk, A; Rosenbaum, M; Papapanou, P N; Desvarieux, M

2015-09-01

Periodontitis and type 2 diabetes mellitus are known to be associated. The relationship between periodontal microbiota and early diabetes risk has not been studied. We investigated the association between periodontal bacteria and prediabetes prevalence among diabetes-free adults. ORIGINS (the Oral Infections, Glucose Intolerance and Insulin Resistance Study) cross sectionally enrolled 300 diabetes-free adults aged 20 to 55 y (mean ± SD, 34 ± 10 y; 77% female). Prediabetes was defined as follows: 1) hemoglobin A1c values ranging from 5.7% to 6.4% or 2) fasting plasma glucose ranging from 100 to 125 mg/dL. In 1,188 subgingival plaque samples, 11 bacterial species were assessed at baseline, including Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Actinomyces naeslundii. Full-mouth clinical periodontal examinations were performed, and participants were defined as having no/mild periodontitis vs. moderate/severe periodontitis per the definition of the Centers for Disease Control and Prevention / American Academy of Periodontology. Modified Poisson regression evaluated prediabetes prevalence across bacterial tertiles. Prevalence ratios and 95% confidence intervals for third vs. first tertiles are presented. All analyses were adjusted for cardiometabolic risk factors. All results presented currently arise from the baseline cross section. Prediabetes prevalence was 18%, and 58% of participants had moderate/severe periodontitis. Prevalence ratios (95% confidence intervals) summarizing associations between bacterial levels and prediabetes were as follows: A. actinomycetemcomitans, 2.48 (1.34, 4.58), P = 0.004; P. gingivalis, 3.41 (1.78, 6.58), P = 0.0003; T. denticola, 1.99 (0.992, 4.00), P = 0.052; T. forsythia, 1.95 (1.0, 3.84), P = 0.05; A. naeslundii, 0.46 (0.25, 0.85), P = 0.01. The prevalence ratio for prediabetes among participants with moderate/severe vs. no/mild periodontitis was 1.47 (0.78, 2.74), P

Brainstem metabotropic glutamate receptors reduce food intake and activate dorsal pontine and medullar structures after peripheral bacterial lipopolysaccharide administration.

PubMed

Chaskiel, Léa; Paul, Flora; Gerstberger, Rüdiger; Hübschle, Thomas; Konsman, Jan Pieter

2016-08-01

During infection-induced inflammation food intake is reduced. Vagal and brainstem pathways are important both in feeding regulation and immune-to-brain communication. Glutamate is released by vagal afferent terminals in the nucleus of the solitary tract and by its neurons projecting to the parabrachial nuclei. We therefore studied the role of brainstem glutamate receptors in spontaneous food intake of healthy animals and during sickness-associated hypophagia after peripheral administration of bacterial lipopolysaccharides or interleukin-1beta. Brainstem group I and II metabotropic, but not ionotropic, glutamate receptor antagonism increased food intake both in saline- and lipopolysaccharide-treated rats. In these animals, expression of the cellular activation marker c-Fos in the lateral parabrachial nuclei and lipopolysaccharide-induced activation of the nucleus of the solitary tract rostral to the area postrema were suppressed. Group I metabotropic glutamate receptors did not colocalize with c-Fos or neurons regulating gastric function in these structures. Group I metabotropic glutamate receptors were, however, found on raphé magnus neurons that were part of the brainstem circuit innervating the stomach and on trigeminal and hypoglossal motor neurons. In conclusion, our findings show that brainstem metabotropic glutamate receptors reduce food intake and activate the lateral parabrachial nuclei as well as the rostral nucleus of the solitary tract after peripheral bacterial lipopolysaccharide administration. They also provide insight into potential group I metabotropic glutamate receptor-dependent brainstem circuits mediating these effects. Copyright © 2016 Elsevier Ltd. All rights reserved.

Expression of macrophage migration inhibitory factor and CD74 in the inner ear and middle ear in lipopolysaccharide-induced otitis media.

PubMed

Ishihara, Hisashi; Kariya, Shin; Okano, Mitsuhiro; Zhao, Pengfei; Maeda, Yukihide; Nishizaki, Kazunori

2016-10-01

Significant expression of macrophage migration inhibitory factor and its receptor (CD74) was observed in both the middle ear and inner ear in experimental otitis media in mice. Modulation of macrophage migration inhibitory factor and its signaling pathway might be useful in the management of inner ear inflammation due to otitis media. Inner ear dysfunction secondary to otitis media has been reported. However, the specific mechanisms involved are not clearly understood. The aim of this study is to investigate the expression of macrophage migration inhibitory factor and CD74 in the middle ear and inner ear in lipopolysaccharide-induced otitis media. BALB/c mice received a transtympanic injection of either lipopolysaccharide or phosphate-buffered saline (PBS). The mice were sacrificed 24 h after injection, and temporal bones were processed for polymerase chain reaction (PCR) analysis, histologic examination, and immunohistochemistry. PCR examination revealed that the lipopolysaccharide-injected mice showed a significant up-regulation of macrophage migration inhibitory factor in both the middle ear and inner ear as compared with the PBS-injected control mice. The immunohistochemical study showed positive reactions for macrophage migration inhibitory factor and CD74 in infiltrating inflammatory cells, middle ear mucosa, and inner ear in the lipopolysaccharide-injected mice.

Nitric oxide mediates the lipopolysaccharide dependent upregulation of the heme oxygenase-1 gene expression in cultured rat Kupffer cells.

PubMed

Immenschuh, S; Tan, M; Ramadori, G

1999-01-01

Heme oxygenase catalyzes the rate-limiting enzymatic step of heme degradation. The inducible isoform of heme oxygenase, heme oxygenase-1, is expressed at a low level in most tissues and is upregulated by its substrate heme and various stress stimuli. Kupffer cells which represent the largest population of the body's tissue macrophages serve physiological functions in the defense against various pathogens such as lipopolysaccharide. The goal of the present study was to investigate the heme oxygenase-1 gene expression in Kupffer cells of rat liver and in isolated Kupffer cell cultures during treatment with lipopolysaccharide. Cryostat sections of normal rat liver were investigated by immunofluorescence double-staining using specific antibodies for rat heme oxygenase-1 and ED2. Isolation and cell culture of Kupffer cells and primary hepatocytes from rat liver, as well as Northern and Western blot analysis, were performed with standard protocols. Heme oxygenase-1 protein was highly expressed in large sinusoidal cells of normal rat liver, which were identified as Kupffer cells by staining with the macrophage surface marker ED2. By contrast, no expression of heme oxygenase-1 was detected in liver parenchymal cells. High expression of heme oxygenase-1 was also found in isolated Kupffer cells in culture by immunocytochemical staining as well as by Western and Northern blot analysis. After treatment of Kupffer cells cultures with lipopolysaccharide, heme oxygenase-1 was upregulated on the protein and mRNA level in a time- and dose-dependent manner. This increase in heme oxygenase-1 expression by lipopolysaccharide was prevented by the nitric oxide inhibitor N(G)-monomethyl-L-arginine which was reversed by an excess of L-arginine. Various nitric oxide donors up-regulated heme oxygenase-1 mRNA expression in Kupffer cells. The lipopolysaccharide-dependent upregulation of the heme oxygenase-1 gene which is highly expressed in Kupffer cells is mediated by a nitric oxide

Cross-reactions of lipopolysaccharides of Pseudomonas aeruginosa in antipneumococcal and other antisera.

PubMed Central

Heidelberger, M; Horton, D; Haskell, T H

1986-01-01

Lipopolysaccharides of the seven Fisher immunotypes of Pseudomonas aeruginosa gave cross-precipitation in many antipneumococcal sera. The reaction of Pseudomonas type IV in type 25 antipneumococcal serum was immediate and heavy: 93 micrograms of antibody nitrogen per ml. Correlations are described, mainly between the structures of the O-chains of the immunotypes and their specificities as shown by the cross-reactions. PMID:3096896

In utero exposure to lipopolysaccharide alters the postnatal acute phase response in beef heifers

USDA-ARS?s Scientific Manuscript database

This study was designed to determine the potential effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal acute phase response (APR) to an LPS challenge in heifers. Pregnant crossbred cows (n = 50) were separated into prenatal immune stimulation (PIS; n = 25; administered 0.1 microgr...

Inhibition of experimental bone resorption and osteoclast formation and survival by 2-aminoethanesulphonic acid.

PubMed

Koide, M; Okahashi, N; Tanaka, R; Kazuno, K; Shibasaki, K; Yamazaki, Y; Kaneko, K; Ueda, N; Ohguchi, M; Ishihara, Y; Noguchi, T; Nishihara, T

1999-09-01

It is known that bone resorption is mediated by osteoclasts, and lipopolysaccharide (LPS) and inflammatory mediators such as interleukin-1 (IL-1) and prostaglandin E2 (PGE2) induce osteoclast differentiation from haemopoietic cells, 2-aminoethanesulphonic acid, which is known as taurine, is an important nutrient and is added to most synthetic human infant milk formulas. In this study, it was found that 2-aminoethanesulphonic acid inhibits the stimulation of bone resorption mediated by LPS of the periodontopathic microorganism Actinobacillus actinomycetemcomitans Y4 in organ cultures of newborn mouse calvaria. The effect of 2-aminoethanesulphonic acid on the development and survival of osteoclast-like multinucleated cells produced in a mouse bone-marrow culture system was also examined. 2-aminoethanesulphonic acid (100 microg/ml) suppressed the formation of these osteoclast-like cells in the presence of LPS of A. actinomycetemcomitans Y4, IL-1alpha or PGE2 in mouse marrow cultures. On the other hand, 2-aminoethanesulphonic acid did not inhibit 1alpha, 25-dihydroxyvitamin D3-mediated osteoclast differentiation. Although IL-1alpha elongated the survival of the osteoclast-like cells, 2-aminoethanesulphonic acid blocked the supportive effect of IL-1alpha on osteoclast survival. 2-aminoethanesulphonic acid showed no effect on the growth of mouse osteoblasts. Finally, it was found that 2-aminoethanesulphonic acid inhibited alveolar bone resorption in experimental periodontitis in hamsters. These results suggest that 2-aminoethanesulphonic acid is an effective agent in preventing inflammatory bone resorption in periodontal diseases.

Structural studies of the polysaccharides from the lipopolysaccharides of Azospirillum brasilense Sp246 and SpBr14.

PubMed

Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Grinev, Vyacheslav S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

2014-10-29

Lipopolysaccharides from closely related Azospirillum brasilense strains, Sp246 and SpBr14, were obtained by phenol-water extraction. Mild acid hydrolysis of the lipopolysaccharides followed by GPC on Sephadex G-50 resulted in polysaccharide mixtures. On the basis of sugar and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy data, it was concluded that both bacteria possess the same two distinct polysaccharides having structures 1 and 2: [structure: see text]. Structure 1 has been reported earlier for a polysaccharide of A. brasilense 54 [Fedonenko et al., 2011] whereas to our knowledge structure 2 has not been hitherto found in bacterial polysaccharides. Copyright © 2014 Elsevier Ltd. All rights reserved.

Biochemical characterization of an ABC transporter LptBFGC complex required for the outer membrane sorting of lipopolysaccharides.

PubMed

Narita, Shin-ichiro; Tokuda, Hajime

2009-07-07

Seven Lpt proteins (A through G) are thought to be involved in lipopolysaccharide transport from the inner to outer membrane of Escherichia coli. LptB belongs to the ATP-binding cassette transporter superfamily. Although the lptB gene lacks neighboring genes encoding membrane subunits, bioinformatic analyses recently indicated that two distantly located consecutive genes, lptF and lptG, could encode membrane subunits. To examine this possibility, LptB was expressed with LptF and LptG. We report here that both LptF and LptG formed a complex with LptB. Furthermore, an inner membrane protein, LptC, which had been implicated in lipopolysaccharide transport, was also included in this complex.

Cyanobacterial lipopolysaccharides and human health – a review

PubMed Central

Stewart, Ian; Schluter, Philip J; Shaw, Glen R

2006-01-01

Cyanobacterial lipopolysaccharide/s (LPS) are frequently cited in the cyanobacteria literature as toxins responsible for a variety of heath effects in humans, from skin rashes to gastrointestinal, respiratory and allergic reactions. The attribution of toxic properties to cyanobacterial LPS dates from the 1970s, when it was thought that lipid A, the toxic moiety of LPS, was structurally and functionally conserved across all Gram-negative bacteria. However, more recent research has shown that this is not the case, and lipid A structures are now known to be very different, expressing properties ranging from LPS agonists, through weak endotoxicity to LPS antagonists. Although cyanobacterial LPS is widely cited as a putative toxin, most of the small number of formal research reports describe cyanobacterial LPS as weakly toxic compared to LPS from the Enterobacteriaceae. We systematically reviewed the literature on cyanobacterial LPS, and also examined the much lager body of literature relating to heterotrophic bacterial LPS and the atypical lipid A structures of some photosynthetic bacteria. While the literature on the biological activity of heterotrophic bacterial LPS is overwhelmingly large and therefore difficult to review for the purposes of exclusion, we were unable to find a convincing body of evidence to suggest that heterotrophic bacterial LPS, in the absence of other virulence factors, is responsible for acute gastrointestinal, dermatological or allergic reactions via natural exposure routes in humans. There is a danger that initial speculation about cyanobacterial LPS may evolve into orthodoxy without basis in research findings. No cyanobacterial lipid A structures have been described and published to date, so a recommendation is made that cyanobacteriologists should not continue to attribute such a diverse range of clinical symptoms to cyanobacterial LPS without research confirmation. PMID:16563160

Arginine supplementation does not alter nitrogen metabolism of beef steers during a lipopolysaccharide challenge

USDA-ARS?s Scientific Manuscript database

Demand for arginine (Arg) is reported to increase during immune challenges. This study evaluated effects of lipopolysaccharide (LPS) and abomasal Arg infusion on nitrogen (N) metabolism and immune response of 20 ruminally cannulated steers (369 ± 46 kg BW) in a randomized block design. Each block co...

An ex vivo ruminal ovine model to study the immediate immune response in the context of bacterial lipopolysaccharide.

PubMed

Abouhajer, Fathi; El-Ashram, Saeed; Karama, Musafiri; Huang, Shujian; Liu, Jian-Feng

2018-05-01

We have set up an ex vivo ovine ruminal model, which can mimic the multicellular process to explore the early steps in Salmonella typhimurium lipopolysaccharide (LPS) stimulation using RNA-seq technology. Ovine ruminal explants were collected for histological and transcriptional analysis and supernatants collected to quantitate lactate dehydrogenase (LDH) enzymes. A total of 8 and 523 genes were significantly over-expressed between LPS-treated and control tissues at 6 and 12 h, respectively. However, six and seven hundred and thirteen genes were substantially repressed between the aforementioned tissues, correspondingly. Key genes up-regulated in response to the addition of LPS were tumor necrosis factor (TNF), interlukin (IL)-1 beta(b), IL-6, IL-8, IL-17B, IL-19, MMP-1, MMP-3, and integrin alpha 2 (ITGA8, 9). This study shows for the first time that galectin-1 is up-regulated in an ex vivo ruminal segment model exposed to bacterial lipopolysaccharide following 6 h of incubation. The ruminal segment model has been shown to be a suitable tool to study the bacterial lipopolysaccharide effects on the ovine ruminal tissues prior to in vivo assessment.

Bacterial lipopolysaccharide-induced systemic inflammation alters perfusion of white matter-rich regions without altering flow in brain-irrigating arteries: Relationship to blood-brain barrier breakdown?

PubMed

Dhaya, Ibtihel; Griton, Marion; Raffard, Gérard; Amri, Mohamed; Hiba, Bassem; Konsman, Jan Pieter

2018-01-15

To better understand brain dysfunction during sepsis, cerebral arterial blood flow was assessed with Phase Contrast Magnetic Resonance Imaging, perfusion with Arterial Spin Labeling and structure with diffusion-weighted Magnetic Resonance Imaging in rats after intraperitoneal administration of bacterial lipopolysaccharides. Although cerebral arterial flow was not altered, perfusion of the corpus callosum region and diffusion parallel to its fibers were higher after lipopolysaccharide administration as compared to saline injection. In parallel, lipopolysaccharide induced perivascular immunoglobulin-immunoreactivity in white matter. These findings indicate that systemic inflammation can result in increased perfusion, blood-brain barrier breakdown and altered water diffusion in white matter. Copyright © 2017 Elsevier B.V. All rights reserved.

Copper sulfate pentahydrate reduced epithelial cytotoxicity induced by lipopolysaccharide from enterogenic bacteria.

PubMed

Feyzi, Adel; Delkhosh, Aref; Nasrabadi, Hamid Tayefi; Cheraghi, Omid; Khakpour, Mansour; Barekati-Mowahed, Mazyar; Soltani, Sina; Mohammadi, Seyede Momeneh; Kazemi, Masoumeh; Hassanpour, Mehdi; Rezabakhsh, Aysa; Maleki-Dizaji, Nasrin; Rahbarghazi, Reza; Namdarian, Reza

2017-05-01

The over usage of multiple antibiotics contributes to the emergence of a whole range of antibiotic-resistant strains of bacteria causing enterogenic infections in poultry science. Therefore, finding an appropriate alternative natural substance carrying an antibacterial capacity would be immensely beneficial. It has been previously discovered that the different types of cupric salts, especially copper sulfate pentahydrate (CuSO 4 ·5H 2 O), to carry a potent bactericidal capacity. We investigated the neutralizing effect of CuSO 4 ·5H 2 O (6.25μg/ml) on the reactive oxygen species generation, and expression of MyD88, an essential adaptor protein of Toll-like receptor, and NF-κB in three intestinal epithelial cell lines exposed to 50ng/ml lipopolysaccharide. In order to find the optimal cupric sulfate concentration without enteritis-inducing toxicity, broiler chickens were initially fed with water containing 0.4, 0.5, and 1mg/l during a period of 4days. After determination of appropriate dosage, two broiler chickens and turkey flocks with enteritis were fed with cupric compound for 4days. We found that cupric sulfate can lessen the cytotoxic effect of lipopolysaccharide by reducing the reactive oxygen species content (p<0.05). Additionally, the expression of MyD88 and NF-κB was remarkably down-regulated in the presence of lipopolysaccharide and cupric sulfate. The copper sulfate in doses lower than 0.4mg/ml expressed no cytotoxic effect on the liver, kidney, and the intestinal tract while a concentration of 0.5 and 1mg/ml contributed to a moderate to severe tissue injuries. Pearson Chi-Square analysis revealed the copper cation significantly diminished the rate of mortality during 4-day feeding of broiler chicken and turkey with enteritis (p=0.000). Thus, the results briefed above all confirm the potent anti-bactericidal feature of cupric sulfate during the course of enteritis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Transcriptional Activation of Mucin by Pseudomonas aeruginosa Lipopolysaccharide in the Pathogenesis of Cystic Fibrosis Lung Disease

NASA Astrophysics Data System (ADS)

Li, Jian-Dong; Dohrman, Austin F.; Gallup, Marianne; Miyata, Susumu; Gum, James R.; Kim, Young S.; Nadel, Jay A.; Prince, Alice; Basbaum, Carol B.

1997-02-01

An unresolved question in cystic fibrosis (CF) research is how mutations of the CF transmembrane conductance regulator, a CI ion channel, cause airway mucus obstruction leading to fatal lung disease. Recent evidence has linked the CF transmembrane conductance regulator mutation to the onset and persistence of Pseudomonas aeruginosa infection in the airways, and here we provide evidence directly linking P. aeruginosa infection to mucus overproduction. We show that P. aeruginosa lipopolysaccharide profoundly upregulates transcription of the mucin gene MUC 2 in epithelial cells via inducible enhancer elements and that this effect is blocked by the tyrosine kinase inhibitors genistein and tyrphostin AG 126. These findings improve our understanding of CF pathogenesis and suggest that the attenuation of mucin production by lipopolysaccharide antagonists and tyrosine kinase inhibitors could reduce morbidity and mortality in this disease.

Heterotrimeric G proteins physically associated with the lipopolysaccharide receptor CD14 modulate both in vivo and in vitro responses to lipopolysaccharide.

PubMed Central

Solomon, K R; Kurt-Jones, E A; Saladino, R A; Stack, A M; Dunn, I F; Ferretti, M; Golenbock, D; Fleisher, G R; Finberg, R W

1998-01-01

Septic shock induced by lipopolysaccharide (LPS) triggering of cytokine production from monocytes/macrophages is a major cause of morbidity and mortality. The major monocyte/macrophage LPS receptor is the glycosylphosphatidylinositol (GPI)-anchored glycoprotein CD14. Here we demonstrate that CD14 coimmunoprecipitates with Gi/Go heterotrimeric G proteins. Furthermore, we demonstrate that heterotrimeric G proteins specifically regulate CD14-mediated, LPS-induced mitogen-activated protein kinase (MAPK) activation and cytokine production in normal human monocytes and cultured cells. We report here that a G protein binding peptide protects rats from LPS-induced mortality, suggesting a functional linkage between a GPI-anchored receptor and the intracellular signaling molecules with which it is physically associated. PMID:9835628

Effects of equine metabolic syndrome on inflammatory responses of horses to intravenous lipopolysaccharide infusion.

PubMed

Tadros, Elizabeth M; Frank, Nicholas; Donnell, Robert L

2013-07-01

To test the hypothesis that inflammatory responses to endotoxemia differ between healthy horses and horses with equine metabolic syndrome (EMS). Animals-6 healthy horses and 6 horses with EMS. Each horse randomly received an IV infusion of lipopolysaccharide (20 ng/kg [in 60 mL of sterile saline {0.9% NaCl} solution]) or saline solution, followed by the other treatment after a 7-day washout period. Baseline data were obtained 30 minutes before each infusion. After infusion, a physical examination was performed hourly for 9 hours and at 15 and 21 hours; a whole blood sample was collected at 30, 60, 90, 120, 180, and 240 minutes for assessment of inflammatory cytokine gene expression. Liver biopsy was performed between 240 and 360 minutes after infusion. Results-Following lipopolysaccharide infusion in healthy horses and horses with EMS, mean rectal temperature, heart rate, and respiratory rate increased, compared with baseline findings, as did whole blood gene expression of interleukin (IL)-1β, IL-6, IL-8, IL-10, and tumor necrosis factor-α. The magnitude of blood cytokine responses did not differ between groups, but increased expression of IL-6, IL-8, IL-10, and tumor necrosis factor-α persisted for longer periods in EMS-affected horses. Lipopolysaccharide infusion increased liver tissue gene expressions of IL-6 in healthy horses and IL-8 in both healthy and EMS-affected horses, but these gene expressions did not differ between groups. Results supported the hypothesis that EMS affects horses' inflammatory responses to endotoxin by prolonging cytokine expression in circulating leukocytes. These findings are relevant to the association between obesity and laminitis in horses with EMS.

Arginine supplementation does not alter nitrogen metabolism of beef steers during a lipopolysaccharide challenge

USDA-ARS?s Scientific Manuscript database

Demand for Arg is reported to increase during immune challenge. This study evaluated the effects of lipopolysaccharide (LPS) and abomasal Arg infusion on N metabolism and immune response of 20 ruminally cannulated steers (369 ± 46 kg BW) in a randomized block design. Each block was 20 d and consiste...

Lectin-Like Bacteriocins from Pseudomonas spp. Utilise D-Rhamnose Containing Lipopolysaccharide as a Cellular Receptor

PubMed Central

Josts, Inokentijs; Roszak, Aleksander W.; Waløen, Kai I.; Cogdell, Richard J.; Milner, Joel; Evans, Tom; Kelly, Sharon; Tucker, Nicholas P.; Byron, Olwyn; Smith, Brian; Walker, Daniel

2014-01-01

Lectin-like bacteriocins consist of tandem monocot mannose-binding domains and display a genus-specific killing activity. Here we show that pyocin L1, a novel member of this family from Pseudomonas aeruginosa, targets susceptible strains of this species through recognition of the common polysaccharide antigen (CPA) of P. aeruginosa lipopolysaccharide that is predominantly a homopolymer of d-rhamnose. Structural and biophysical analyses show that recognition of CPA occurs through the C-terminal carbohydrate-binding domain of pyocin L1 and that this interaction is a prerequisite for bactericidal activity. Further to this, we show that the previously described lectin-like bacteriocin putidacin L1 shows a similar carbohydrate-binding specificity, indicating that oligosaccharides containing d-rhamnose and not d-mannose, as was previously thought, are the physiologically relevant ligands for this group of bacteriocins. The widespread inclusion of d-rhamnose in the lipopolysaccharide of members of the genus Pseudomonas explains the unusual genus-specific activity of the lectin-like bacteriocins. PMID:24516380

An Integrated Omics Analysis: Impact of Microgravity on Host Response to Lipopolysaccharide in vitro

DTIC Science & Technology

2014-08-07

on host response to lipopolysaccharide in vitro 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Nabarun Chakraborty...49. Mateescu B, Batista L, Cardon M, Gruosso T, de Feraudy Y, Mariani O, Nicolas A, Meyniel JP, Cottu P, Sastre Garau X, Mechta Grigoriou F: miR 141

EFFECTS OF CHRONIC EXERCISE CONDITIONING ON THERMAL RESPONSES TO LIPOPOLYSACCHARIDE AND TURPENTINE ABSCESS IN FEMALE RATS.

EPA Science Inventory

Chronic exercise conditioning has been shown to alter basal thermoregulatory processes as well as the response to inflammatory agents. Two such agents, lipopolysaccharide (LPS) and turpentine (TPT) are inducers of fever in rats. LPS, given intraperitoneally (i.p.), involves a sys...

The Cytolethal Distending Toxin Induces Receptor Activator of NF-κB Ligand Expression in Human Gingival Fibroblasts and Periodontal Ligament Cells

PubMed Central

Belibasakis, G. N.; Johansson, A.; Wang, Y.; Chen, C.; Kalfas, S.; Lerner, U. H.

2005-01-01

Actinobacillus actinomycetemcomitans is associated with localized aggressive periodontitis, a disease characterized by rapid loss of the alveolar bone surrounding the teeth. Receptor activator of NF-κB Ligand (RANKL) and osteoprotegerin (OPG) are two molecules that regulate osteoclast formation and bone resorption. RANKL induces osteoclast differentiation and activation, whereas OPG blocks this process by acting as a decoy receptor for RANKL. The purpose of this study was to investigate the effect of A. actinomycetemcomitans on the expression of RANKL and OPG in human gingival fibroblasts and periodontal ligament cells. RANKL mRNA expression was induced in both cell types challenged by A. actinomycetemcomitans extract, whereas OPG mRNA expression remained unaffected. Cell surface RANKL protein was also induced by A. actinomycetemcomitans, whereas there was no change in OPG protein secretion. A cytolethal distending toxin (Cdt) gene-knockout strain of A. actinomycetemcomitans did not induce RANKL expression, in contrast to its wild-type strain. Purified Cdt from Haemophilus ducreyi alone, or in combination with extract from the A. actinomycetemcomitans cdt mutant strain, induced RANKL expression. Pretreatment of A. actinomycetemcomitans wild-type extract with Cdt antiserum abolished RANKL expression. In conclusion, A. actinomycetemcomitans induces RANKL expression in periodontal connective tissue cells. Cdt is crucial for this induction and may therefore be involved in the pathological bone resorption during the process of localized aggressive periodontitis. PMID:15618171

Enhanced interleukin-8 production in THP-1 human monocytic cells by lipopolysaccharide from oral microorganisms and granulocyte-macrophage colony-stimulating factor.

PubMed

Baqui, A A; Meiller, T F; Falkler, W A

1999-10-01

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has been used to assist in bone marrow recovery during cancer chemotherapy. Interleukin-8 (IL-8) plays an important role in macrophage mediated inflammatory processes including exacerbation of periodontal diseases, one of the most common complications in GM-CSF receiving cancer patients. The effect of GM-CSF supplementation on IL-8 production was investigated in a human monocyte cell line THP-1, stimulated with lipopolysaccharide extracted from two oral microorganisms, Porphyromonas gingivalis and Fusobacterium nucleatum. Resting THP-1 cells were treated with lipopolysaccharide (1 microgram/ml) of P. gingivalis or F. nucleatum and/or GM-CSF (50 IU/ml) for varying time periods. The production of IL-8 in THP-1 cells was measured by a solid-phase enzyme-linked immunosorbent assay (ELISA). A very low level of the cytokine IL-8 was produced constitutive in THP-1 cells. Starting from 8 h of treatment and afterwards GM-CSF alone significantly increased IL-8 production in THP-1 cells. Lipopolysaccharide (1 microgram/ml) extracts from either F. nucleatum or P. gingivalis amplified IL-8 production 500-800 times in comparison to resting THP-1 cells. When lipopolysaccharide of F. nucleatum or P. gingivalis was supplemented with 50 IU/ml of GM-CSF, there was a statistically significant enhanced production of IL-8 by THP-1 cells after 1 day to 7 days of treatment as compared with lipopolysaccharide treatment alone. GM-CSF (50 IU/ml) also significantly increased IL-8 production from 2-7 days of treatment of THP-1 cells when supplemented with a positive control, phorbol-12-myristate-13 acetate (PMA), as compared to PMA treatment alone. These investigations using the in vitro THP-1 human monocyte cell model indicate that there may be an increase in the response on a cellular level to oral endotoxin following GM-CSF therapy as evidenced by enhanced production of the tissue-reactive inflammatory cytokine, IL-8.

Structural insight into lipopolysaccharide transport from the Gram-negative bacterial inner membrane to the outer membrane.

PubMed

Dong, Haohao; Tang, Xiaodi; Zhang, Zhengyu; Dong, Changjiang

2017-11-01

Lipopolysaccharide (LPS) is an important component of the outer membrane (OM) of Gram-negative bacteria, playing essential roles in protecting bacteria from harsh environments, in drug resistance and in pathogenesis. LPS is synthesized in the cytoplasm and translocated to the periplasmic side of the inner membrane (IM), where it matures. Seven lipopolysaccharide transport proteins, LptA-G, form a trans‑envelope complex that is responsible for LPS extraction from the IM and transporting it across the periplasm to the OM. The LptD/E of the complex transports LPS across the OM and inserts it into the outer leaflet of the OM. In this review we focus upon structural and mechanistic studies of LPS transport proteins, with a particular focus upon the LPS ABC transporter LptB 2 FG. This ATP binding cassette transporter complex consists of twelve transmembrane segments and has a unique mechanism whereby it extracts LPS from the periplasmic face of the IM through a pair of lateral gates and then powers trans‑periplasmic transport to the OM through a slide formed by either of the periplasmic domains of LptF or LptG, LptC, LptA and the N-terminal domain of LptD. The structural and functional studies of the seven lipopolysaccharide transport proteins provide a platform to explore the unusual mechanisms of LPS extraction, transport and insertion from the inner membrane to the outer membrane. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop. Copyright © 2017 Elsevier B.V. All rights reserved.

Prunus mume extract exhibits antimicrobial activity against pathogenic oral bacteria.

PubMed

Seneviratne, Chamida J; Wong, Ricky W K; Hägg, Urban; Chen, Yong; Herath, Thanuja D K; Samaranayake, P Lakshman; Kao, Richard

2011-07-01

Prunus mume is a common fruit in Asia, which has been used in traditional Chinese medicine. In this study, we focused on the antimicrobial properties of Prunus mume extract against oral pathogens related to dental caries and periodontal diseases. A total of 15 oral pathogens including Streptococcus mutans, S. sobrinus, S. mitis, S. sanguinis, Lactobacillus acidophilus, P. gingivalis, Aggregatibacter actinomycetemcomitans, and Candida species were included in the study. Initially, agar diffusion assay was performed to screen the antimicrobial activities of Prunus mume extract. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were then determined for sensitive species. Effect of Prunus mume extract on human oral keratinocytes (HOK) viability was also tested. In the agar diffusion assay, drug suspension of 2 g/mL was able to inhibit all the bacterial species tested, but not the fungal species. MIC and MBC range of Prunus mume extract against the oral bacteria was 0.15625-0.0003 g/mL and P. gingivalis being the most susceptible species. Prune extract did not cause any detrimental effect on HOK. Prunus mume extract may be a potential candidate for developing an oral antimicrobial agent to control or prevent dental diseases associated with oral pathogenic bacteria. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

Does obesity influence the subgingival microbiota composition in periodontal health and disease?

PubMed

Maciel, Suellen Silva; Feres, Magda; Gonçalves, Tiago Eduardo Dias; Zimmermann, Glaucia Santos; da Silva, Hélio Doyle Pereira; Figueiredo, Luciene Cristina; Duarte, Poliana Mendes

2016-12-01

To evaluate whether obesity affects the subgingival microbial composition of patients with periodontal health or chronic periodontitis (CP). Based on periodontal parameters, body mass index and waist-hip ratio, 166 patients were allocated into one of the following groups: Normal weight (NW) patients with periodontal health (n = 44), NW patients with CP (n = 40), obese patients with periodontal health (n = 40) and obese patients with CP (n = 42). Six subgingival biofilm samples per patient were analysed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. Obese patients with CP harboured higher levels and/or higher proportions of several periodontal pathogens than those with NW and CP, including Aggregatibacter actinomycetemcomitans, Eubacterium nodatum, Fusobacterium nucleatum ss vincentii, Parvimonas micra, Prevotella intermedia, Tannerella forsythia, Prevotella melaninogenica and Treponema socranskii. The proportions of most of these pathogens, as well Campylobacter rectus and Eikenella corrodens, were more increased in the diseased sites of the obese patients than in those with NW. Furthermore, the healthy sites of the obese patients, presenting or not CP, also exhibited higher proportions of some of the pathogens than patients with NW. Obesity is associated with increased levels and proportions of periodontal pathogens, especially in patients with CP. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Relationship of clinical and microbiological variables in patients with type 1 diabetes mellitus and periodontitis.

PubMed

Sakalauskiene, Jurgina; Kubilius, Ricardas; Gleiznys, Alvydas; Vitkauskiene, Astra; Ivanauskiene, Egle; Šaferis, Viktoras

2014-10-08

The aim of the study was to analyze how metabolic control of type 1 diabetes is related to clinical and microbiological periodontal parameters. The study involved 56 subjects aged from 19 to 50 years divided into 2 groups: healthy subjects (the H group), and diabetic (type 1 diabetes) patients with chronic untreated generalized periodontitis (the DM group). The glycosylated hemoglobin value (HbA1c) was determined using the UniCel DxC 800 SYNCHRON System (Beckman Coulter, USA), and the concentration in blood was measured by the turbidimetric immunoinhibition method. A molecular genetic assay (Micro-IDent plus, Germany) was used to detect periodontopathogenic bacteria in plaque samples. Periodontitis was confirmed by clinical and radiological examination. Fusobacterium nucleatum, Capnocytophaga species, and Eikenella corrodens were the most frequently found bacteria in dental plaque samples (77.8%, 66.7%, and 33.4%, respectively), whereas Aggregatibacter actinomycetemcomitans was identified 40.7% less frequently in the DM group than in the H group. The strongest relationship was observed between the presence of 2 periodontal pathogens - F. nucleatum and Capnocytophaga spp. - and poorer metabolic control in type 1 diabetes patients (HbA1c) and all clinical parameters of periodontal pathology. Periodontal disease was more evident in type 1 diabetic patients, and the prevalence of periodontitis was greatly increased in subjects with poorer metabolic control.

The association between subgingival periodontal pathogens and systemic inflammation.

PubMed

Winning, Lewis; Patterson, Christopher C; Cullen, Kathy M; Stevenson, Kathryn A; Lundy, Fionnuala T; Kee, Frank; Linden, Gerard J

2015-09-01

To investigate associations between periodontal disease pathogens and levels of systemic inflammation measured by C-reactive protein (CRP). A representative sample of dentate 60-70-year-old men in Northern Ireland had a comprehensive periodontal examination. Men taking statins were excluded. Subgingival plaque samples were analysed by quantitative real time PCR to identify the presence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia. High-sensitivity CRP (mg/l) was measured from fasting blood samples. Multiple linear regression analysis was performed using log-transformed CRP concentration as the dependent variable, with the presence of each periodontal pathogen as predictor variables, with adjustment for various potential confounders. A total of 518 men (mean age 63.6 SD 3.0 years) were included in the analysis. Multiple regression analysis showed that body mass index (p < 0.001), current smoking (p < 0.01), the detectable presence of P. gingivalis (p < 0.01) and hypertension (p = 0.01), were independently associated with an increased CRP. The detectable presence of P. gingivalis was associated with a 20% (95% confidence interval 4-35%) increase in CRP (mg/l) after adjustment for all other predictor variables. In these 60-70-year-old dentate men, the presence of P. gingivalis in subgingival plaque was significantly associated with a raised level of C-reactive protein. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Efficacy of taurolidine against periodontopathic species--an in vitro study.

PubMed

Eick, Sigrun; Radakovic, Sabrina; Pfister, Wolfgang; Nietzsche, Sandor; Sculean, Anton

2012-06-01

The antimicrobial effect of taurolidine was tested against periodontopathic species in comparison to chlorhexidine digluconate in the presence or absence of serum. Minimal inhibitory concentrations (MIC), microbiocidal concentrations (MBC), as well as killing were determined against 32 different microbial strains including 3 Porphyromonas gingivalis, 3 Aggregatibacter actinomycetemcomitans, and 15 potentially superinfecting species with and without 25% v/v human serum. The MIC(50) of taurolidine against the tested microbial strains was 0.025% and the MIC(90) 0.05%. The respective values for the MBCs were 0.05% and 0.1%. Addition of 25% serum (heat-inactivated) did not change the MIC and MBC values of taurolidine. In contrast, MICs and MBCs of chlorhexidine (CHX) increased by two steps after addition of serum. Taurolidine killed microorganisms in a concentration and time-dependent manner, the killing rate of 1.6% taurolidine was 99.08% ± 2.27% in mean after 2 h. Again, killing activity of taurolidine was not affected if serum was added, whereas addition of inactivated serum clearly reduced the killing rate of all selected bacterial strains by CHX. Therefore, taurolidine possesses antimicrobial properties which are not reduced in the presence of serum as a main component in gingival crevicular fluid and wound fluid. Taurolidine may have potential as an antimicrobial agent in non-surgical and surgical periodontal treatment.

Protective effect of topical Cordia verbenacea in a rat periodontitis model: immune-inflammatory, antibacterial and morphometric assays.

PubMed

Pimentel, Suzana Peres; Barrella, Guilherme Emerson; Casarin, Renato Corrêa Viana; Cirano, Fabiano Ribeiro; Casati, Márcio Zaffalon; Foglio, Mary Ann; Figueira, Glyn Mara; Ribeiro, Fernanda Vieira

2012-11-21

This study evaluated the effects of C. verbenacea essential oil topically administered in a rat periodontitis model. Periodontitis was induced on rats in one of the mandibular first molars assigned to receive a ligature. Animals were randomly divided into two groups: a) non-treatment group (NT) (n = 18): animals received 1mL of vehicle; b) C. verbenacea group (C.v.) (n = 18): animals received 5mg/Kg of essential oils isolated from C. verbenacea. The therapies were administered topically 3 times daily for 11 days. Then, the specimens were processed for morphometric analysis of bone loss. The ligatures were used for microbiological assessment of the presence of Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Porphyromonas gingivalis using PCR. The gingival tissue was collected to Elisa assay of interleukin (IL)-1α and IL-10 levels. Bone loss was inhibited by C. verbenacea when compared to the NT group (p < 0.05). A decrease in the levels of IL-1α and increase in the IL-10 amounts was observed in the C.v. group as compared to NT group (p < 0.05). A lower frequency of P. gingivalis was found in C.v. group (p < 0.05). C. verbenacea essential oil topically administered diminished alveolar bone resorption, promoting a positive local imbalance in the pro/anti-inflammatory system and reducing the frequency of detection of P. gingivalis.

Comparison of the detection of periodontal pathogens in bacteraemia after tooth brushing by culture and molecular techniques.

PubMed

Marín, M-J; Figuero, E; González, I; O'Connor, A; Diz, P; Álvarez, M; Herrera, D; Sanz, M

2016-05-01

The prevalence and amounts of periodontal pathogens detected in bacteraemia samples after tooth brushing-induced by means of four diagnostic technique, three based on culture and one in a molecular-based technique, have been compared in this study. Blood samples were collected from thirty-six subjects with different periodontal status (17 were healthy, 10 with gingivitis and 9 with periodontitis) at baseline and 2 minutes after tooth brushing. Each sample was analyzed by three culture-based methods [direct anaerobic culturing (DAC), hemo-culture (BACTEC), and lysis-centrifugation (LC)] and one molecular-based technique [quantitative polymerase chain reaction (qPCR)]. With culture any bacterial isolate was detected and quantified, while with qPCR only Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were detected and quantified. Descriptive analyses, ANOVA and Chi-squared tests, were performed. Neither BACTEC nor qPCR detected any type of bacteria in the blood samples. Only LC (2.7%) and DAC (8.3%) detected bacteraemia, although not in the same patients. Fusobacterium nucleatum was the most frequently detected bacterial species. The disparity in the results when the same samples were analyzed with four different microbiological detection methods highlights the need for a proper validation of the methodology to detect periodontal pathogens in bacteraemia samples, mainly when the presence of periodontal pathogens in blood samples after tooth brushing was very seldom.

Prenatal transportation alters the metabolic response of Brahman bull calves exposed to a lipopolysaccharide (LPS) challenge

USDA-ARS?s Scientific Manuscript database

This study was designed to determine if prenatal transportation influences the metabolic response to a postnatal lipopolysaccharide (LPS) challenge. Pregnant Brahman cows (n=96) matched by age and parity were separated into transported (TRANS; n=48; transported for 2 hours on gestational day 60, 80,...

Transcriptional profiles of Rel/NF-κB, inhibitor of NF-κB (IκB), and lipopolysaccharide-induced TNF-α factor (LITAF) in the lipopolysaccharide (LPS) and two Vibrio sp.-exposed intertidal copepod, Tigriopus japonicus.

PubMed

Kim, Bo-Mi; Jeong, Chang-Bum; Rhee, Jae-Sung; Lee, Jae-Seong

2014-02-01

The immune system and the role of immunity-related genes have rarely been studied in copepods, even though copepods have a primitive immune response system and also have a potential in pathogen transport higher trophic levels. In this study, we firstly cloned and characterized three core immune genes such as nuclear factor κB (NF-κB), inhibitor of NF-κB (IκB), and lipopolysaccharide-induced TNF-α factor (LITAF) genes in the intertidal copepod Tigriopus japonicus. Several in silico analyses based on conserved domains, motifs, and phylogenetic relationships were supporting their annotations. To investigate the immune-related role of three genes, we exposed lipopolysaccharide (LPS) and two Vibrio sp. to T. japonicus. After exposure of different concentrations of LPS and two Vibrio sp., transcripts of TJ-IκB and TJ-LITAF genes were significantly elevated during the time course in a dose-dependent manner, while TJ-NF-κB transcripts were not significantly changed during exposure. These findings demonstrated that the copepod T. japonicus has a conserved immunity against infection. Copyright © 2013 Elsevier Ltd. All rights reserved.

Identification of Actinobacillus actinomycetemcomitans, Treponema denticola and Porphyromonas gingivalis within human dental calculus: a pilot investigation.

PubMed

Calabrese, Nicolino; Galgut, Peter; Mordan, Nicola

2007-10-01

Dental calculus is considered to be simply a "plaque-retentive factor", and therefore only a secondary aetiological factor in the pathogenesis of periodontitis. Recent studies have suggested a more active role for calculus. Our objective was to demonstrate the presence of periodontal pathogens in the non-mineralised areas of supra- and subgingival dental calculus. Subjects for the study were derived from patients with substantial amounts of supragingival calculus in the lower anterior region who had moderate periodontal disease, having been referred to the periodontal department at the Eastman Dental Hospital for periodontal care. Calculus was removed in as large pieces as possible by the use of a sickle or a push scaler placed underneath the apical or facial border of the calculus and fracturing it from the tooth surface in a single stroke. The orientation and absence of dental plaque was confirmed using light microscopy for each sample prior to inclusion in this study. Samples were prepared for transmission electron microscopic (TEM) observation after immunogold staining with polyclonal antibodies for the presence of Actinobacillus actinomycetemcomitans (A. a.), Porphyromonas gingivalis (P. g.) and Treponema denticola (T. d.). Most of the samples contained at least one of the bacterial species examined, either in the lacunae or in the covering dental plaque. T. d. was the most frequently identified species and was found in nearly all of the subgingival samples, whilstA. a. was rarely observed. In this limited study, supra- and subgingival dental calculus appears to be capable of maintaining periodontal pathogens within the deep recesses of its structural lacunae and channels. Therefore, calculus could possibly play a relevant role in the aetiology and pathogenesis of periodontitis. The presence of T. d. in the majority of specimens requires further investigation as its pathogenic potential may be underestimated in current published microbiological research, and

Deciphering minimal antigenic epitopes associated with Burkholderia pseudomallei and Burkholderia mallei lipopolysaccharide O-antigens.

PubMed

Tamigney Kenfack, Marielle; Mazur, Marcelina; Nualnoi, Teerapat; Shaffer, Teresa L; Ngassimou, Abba; Blériot, Yves; Marrot, Jérôme; Marchetti, Roberta; Sintiprungrat, Kitisak; Chantratita, Narisara; Silipo, Alba; Molinaro, Antonio; AuCoin, David P; Burtnick, Mary N; Brett, Paul J; Gauthier, Charles

2017-07-24

Burkholderia pseudomallei (Bp) and Burkholderia mallei (Bm), the etiologic agents of melioidosis and glanders, respectively, cause severe disease in both humans and animals. Studies have highlighted the importance of Bp and Bm lipopolysaccharides (LPS) as vaccine candidates. Here we describe the synthesis of seven oligosaccharides as the minimal structures featuring all of the reported acetylation/methylation patterns associated with Bp and Bm LPS O-antigens (OAgs). Our approach is based on the conversion of an L-rhamnose into a 6-deoxy-L-talose residue at a late stage of the synthetic sequence. Using biochemical and biophysical methods, we demonstrate the binding of several Bp and Bm LPS-specific monoclonal antibodies with terminal OAg residues. Mice immunized with terminal disaccharide-CRM197 constructs produced high-titer antibody responses that crossreacted with Bm-like OAgs. Collectively, these studies serve as foundation for the development of novel therapeutics, diagnostics, and vaccine candidates to combat diseases caused by Bp and Bm.Melioidosis and glanders are multifaceted infections caused by gram-negative bacteria. Here, the authors synthesize a series of oligosaccharides that mimic the lipopolysaccharides present on the pathogens' surface and use them to develop novel glycoconjugates for vaccine development.

Temporal pattern and effect of sex on lipopolysaccharide-induced stress hormone and cytokine response in pigs

USDA-ARS?s Scientific Manuscript database

The temporal pattern and gender effect of immune and stress hormone responses to a lipopolysaccharide (LPS) challenge were assessed using a pig model. Secretion of the pro-inflammatory cytokines tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6 increased in a time-dependent manner f...

The Escherichia coli Lpt transenvelope protein complex for lipopolysaccharide export is assembled via conserved structurally homologous domains.

PubMed

Villa, Riccardo; Martorana, Alessandra M; Okuda, Suguru; Gourlay, Louise J; Nardini, Marco; Sperandeo, Paola; Dehò, Gianni; Bolognesi, Martino; Kahne, Daniel; Polissi, Alessandra

2013-03-01

Lipopolysaccharide is a major glycolipid component in the outer leaflet of the outer membrane (OM), a peculiar permeability barrier of Gram-negative bacteria that prevents many toxic compounds from entering the cell. Lipopolysaccharide transport (Lpt) across the periplasmic space and its assembly at the Escherichia coli cell surface are carried out by a transenvelope complex of seven essential Lpt proteins spanning the inner membrane (LptBCFG), the periplasm (LptA), and the OM (LptDE), which appears to operate as a unique machinery. LptC is an essential inner membrane-anchored protein with a large periplasm-protruding domain. LptC binds the inner membrane LptBFG ABC transporter and interacts with the periplasmic protein LptA. However, its role in lipopolysaccharide transport is unclear. Here we show that LptC lacking the transmembrane region is viable and can bind the LptBFG inner membrane complex; thus, the essential LptC functions are located in the periplasmic domain. In addition, we characterize two previously described inactive single mutations at two conserved glycines (G56V and G153R, respectively) of the LptC periplasmic domain, showing that neither mutant is able to assemble the transenvelope machinery. However, while LptCG56V failed to copurify any Lpt component, LptCG153R was able to interact with the inner membrane protein complex LptBFG. Overall, our data further support the model whereby the bridge connecting the inner and outer membranes would be based on the conserved structurally homologous jellyroll domain shared by five out of the seven Lpt components.

The Escherichia coli Lpt Transenvelope Protein Complex for Lipopolysaccharide Export Is Assembled via Conserved Structurally Homologous Domains

PubMed Central

Villa, Riccardo; Martorana, Alessandra M.; Okuda, Suguru; Gourlay, Louise J.; Nardini, Marco; Sperandeo, Paola; Dehò, Gianni; Bolognesi, Martino; Kahne, Daniel

2013-01-01

Lipopolysaccharide is a major glycolipid component in the outer leaflet of the outer membrane (OM), a peculiar permeability barrier of Gram-negative bacteria that prevents many toxic compounds from entering the cell. Lipopolysaccharide transport (Lpt) across the periplasmic space and its assembly at the Escherichia coli cell surface are carried out by a transenvelope complex of seven essential Lpt proteins spanning the inner membrane (LptBCFG), the periplasm (LptA), and the OM (LptDE), which appears to operate as a unique machinery. LptC is an essential inner membrane-anchored protein with a large periplasm-protruding domain. LptC binds the inner membrane LptBFG ABC transporter and interacts with the periplasmic protein LptA. However, its role in lipopolysaccharide transport is unclear. Here we show that LptC lacking the transmembrane region is viable and can bind the LptBFG inner membrane complex; thus, the essential LptC functions are located in the periplasmic domain. In addition, we characterize two previously described inactive single mutations at two conserved glycines (G56V and G153R, respectively) of the LptC periplasmic domain, showing that neither mutant is able to assemble the transenvelope machinery. However, while LptCG56V failed to copurify any Lpt component, LptCG153R was able to interact with the inner membrane protein complex LptBFG. Overall, our data further support the model whereby the bridge connecting the inner and outer membranes would be based on the conserved structurally homologous jellyroll domain shared by five out of the seven Lpt components. PMID:23292770

Human thioredoxin-1 attenuates the rate of lipopolysaccharide-induced preterm delivery in mice in association with its anti-inflammatory effect.

PubMed

Namba, Fumihiko; Kobayashi-Miura, Mikiko; Goda, Taro; Nakura, Yukiko; Nishiumi, Fumiko; Son, Aoi; Kubota, Akio; Yodoi, Junji; Yanagihara, Itaru

2016-09-01

Maternal intrauterine infection/inflammation represents the major etiology of preterm delivery and the leading cause of neonatal mortality and morbidity. The aim of this study was to investigate the anti-inflammatory properties of thioredoxin-1 in vivo and its potential ability to attenuate the rate of inflammation-induced preterm delivery. Two intraperitoneal injections of lipopolysaccharide from Escherichia coli were administered in pregnant mice on gestational day 15, with a 3-h interval between the injections. From either 1 h before or 1 h after the first lipopolysaccharide injection, mice received three intravenous injections of either recombinant human thioredoxin-1, ovalbumin, or vehicle, with a 3-h interval between injections. Intraperitoneal injection of lipopolysaccharide induced a rise of tumor necrosis factor-α, interferon-γ, monocyte chemotactic protein 1, and interleukin-6 in maternal serum levels and provoked preterm delivery. Recombinant human thoredoxin-1 prevented the rise in these proinflammatory cytokine levels. After the inflammatory challenge, placentas exhibited severe maternal vascular dilatation and congestion and a marked decidual neutrophil activation. These placental pathological findings were ameliorated by recombinant human thioredoxin-1, and the rate of inflammation-induced preterm delivery was attenuated. Thioredoxin-1 may thus represent a novel effective treatment to delay inflammation-induced preterm delivery.

Characterization of Xylella fastidiosa lipopolysaccharide and its role in key steps of the disease cycle in grapevine

USDA-ARS?s Scientific Manuscript database

This project aims to elucidate molecular mechanisms of Xylella fastidiosa (Xf) pathogenicity. Work is focused on the lipopolysaccharide (LPS) component of the outer membrane, which consists of lipid A, core oligosaccharides, and a variable O-antigen moiety. Specifically, the O-antigen portion of LPS...

Effects of dietary humic and butyric acid on growth performance and response to lipopolysaccharide in young pigs

USDA-ARS?s Scientific Manuscript database

Humic acid (MFG) and fat protected butyric acid (BA) has been shown to modulate energy metabolism and inflammation. Therefore, the objectives of this study were to determine the effects of MFG and BA, alone and in combination, on growth performance and response to lipopolysaccharide (LPS) induced in...

Effect of threonine on secretory immune system using a chicken intestinal ex vivo model with lipopolysaccharide challenge

USDA-ARS?s Scientific Manuscript database

Secretory IgA (sIgA) and its transcytosis receptor, polymeric immunoglobulin receptor (pIgR), along with mucus, form the first lines of intestinal defense. Threonine (Thr) is a major constituent component of intestinal mucins and IgA, which are highly secreted under lipopolysaccharide (LPS) induced ...

Correction to: Top Down Tandem Mass Spectrometric Analysis of a Chemically Modified Rough-Type Lipopolysaccharide Vaccine Candidate

NASA Astrophysics Data System (ADS)

Oyler, Benjamin L.; Khan, Mohd M.; Smith, Donald F.; Harberts, Erin M.; Kilgour, David P. A.; Ernst, Robert K.; Cross, Alan S.; Goodlett, David R.

2018-04-01

In the preceding article "Top Down Tandem Mass Spectrometric Analysis of a Chemically Modified Rough-Type Lipopolysaccharide Vaccine Candidate" by Oyler et al., an error in the J5 E. coli LPS chemical structure (Figs. 2 and 4) was introduced and propagated into the final revision.

Serratia marcescens Induces Apoptotic Cell Death in Host Immune Cells via a Lipopolysaccharide- and Flagella-dependent Mechanism*

PubMed Central

Ishii, Kenichi; Adachi, Tatsuo; Imamura, Katsutoshi; Takano, Shinya; Usui, Kimihito; Suzuki, Kazushi; Hamamoto, Hiroshi; Watanabe, Takeshi; Sekimizu, Kazuhisa

2012-01-01

Injection of Serratia marcescens into the blood (hemolymph) of the silkworm, Bombyx mori, induced the activation of c-Jun NH2-terminal kinase (JNK), followed by caspase activation and apoptosis of blood cells (hemocytes). This process impaired the innate immune response in which pathogen cell wall components, such as glucan, stimulate hemocytes, leading to the activation of insect cytokine paralytic peptide. S. marcescens induced apoptotic cell death of silkworm hemocytes and mouse peritoneal macrophages in vitro. We searched for S. marcescens transposon mutants with attenuated ability to induce apoptosis of silkworm hemocytes. Among the genes identified, disruption mutants of wecA (a gene involved in lipopolysaccharide O-antigen synthesis), and flhD and fliR (essential genes in flagella synthesis) showed reduced motility and impaired induction of mouse macrophage cell death. These findings suggest that S. marcescens induces apoptosis of host immune cells via lipopolysaccharide- and flagella-dependent motility, leading to the suppression of host innate immunity. PMID:22859304

Atomic force microscopy observation of lipopolysaccharide-induced cardiomyocyte cytoskeleton reorganization.

PubMed

Wang, Liqun; Chen, Tangting; Zhou, Xiang; Huang, Qiaobing; Jin, Chunhua

2013-08-01

We applied atomic force microscopy (AFM) to observe lipopolysaccharide (LPS)-induced intracellular cytoskeleton reorganization in primary cardiomyocytes from neonatal mouse. The nonionic detergent Triton X-100 was used to remove the membrane, soluble proteins, and organelles from the cell. The remaining cytoskeleton can then be directly visualized by AFM. Using three-dimensional technique of AFM, we were able to quantify the changes of cytoskeleton by the "density" and total "volume" of the cytoskeleton fibers. Compared to the control group, the density of cytoskeleton was remarkably decreased and the volume of cytoskeleton was significantly increased after LPS treatment, which suggests that LPS may induce the cytoskeleton reorganization and change the cardiomyocyte morphology. Copyright © 2013 Elsevier Ltd. All rights reserved.

Protopine reduces the inflammatory activity of lipopolysaccharide-stimulated murine macrophages.

PubMed

Bae, Deok Sung; Kim, Young Hoon; Pan, Cheol-Ho; Nho, Chu Won; Samdan, Javzan; Yansan, Jamyansan; Lee, Jae Kown

2012-02-01

Protopine is an isoquinoline alkaloid contained in plants in northeast Asia. In this study, we investigated whether protopine derived from Hypecoum erectum L could suppress lipopolysaccharide (LPS)-induced inflammatory responses in murine macrophages (Raw 264.7 cells). Protopine was found to reduce nitric oxide (NO), cyclooxygenase-2 (COX-2), and prostaglandin E(2) (PGE(2)) production by LPS-stimulated Raw 264.7 cells, without a cytotoxic effect. Pre-treatment of Raw 264.7 cells with protopine reduced the production of pro-inflammatory cytokines. These inhibitory effects were caused by blocking phosphorylation of mitogen-activated protein kinases (MAP kinases) and also blocking activation of a nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB).

Quantitative PCR analysis of salivary pathogen burden in periodontitis

PubMed Central

Salminen, Aino; Kopra, K. A. Elisa; Hyvärinen, Kati; Paju, Susanna; Mäntylä, Päivi; Buhlin, Kåre; Nieminen, Markku S.; Sinisalo, Juha; Pussinen, Pirkko J.

2015-01-01

Our aim was to investigate the value of salivary concentrations of four major periodontal pathogens and their combination in diagnostics of periodontitis. The Parogene study included 462 dentate subjects (mean age 62.9 ± 9.2 years) with coronary artery disease (CAD) diagnosis who underwent an extensive clinical and radiographic oral examination. Salivary levels of four major periodontal bacteria were measured by quantitative real-time PCR (qPCR). Median salivary concentrations of Porphyromonas gingivalis, Tannerella forsythia, and Prevotella intermedia, as well as the sum of the concentrations of the four bacteria, were higher in subjects with moderate to severe periodontitis compared to subjects with no to mild periodontitis. Median salivary Aggregatibacter actinomycetemcomitans concentrations did not differ significantly between the subjects with no to mild periodontitis and subjects with moderate to severe periodontitis. In logistic regression analysis adjusted for age, gender, diabetes, and the number of teeth and implants, high salivary concentrations of P. gingivalis, T. forsythia, and P. intermedia were significantly associated with moderate to severe periodontitis. When looking at different clinical and radiographic parameters of periodontitis, high concentrations of P. gingivalis and T. forsythia were significantly associated with the number of 4–5 mm periodontal pockets, ≥6 mm pockets, and alveolar bone loss (ABL). High level of T. forsythia was associated also with bleeding on probing (BOP). The combination of the four bacteria, i.e., the bacterial burden index, was associated with moderate to severe periodontitis with an odds ratio (OR) of 2.40 (95% CI 1.39–4.13). When A. actinomycetemcomitans was excluded from the combination of the bacteria, the OR was improved to 2.61 (95% CI 1.51–4.52). The highest OR 3.59 (95% CI 1.94–6.63) was achieved when P. intermedia was further excluded from the combination and only the levels of P. gingivalis and

The Interaction of Implant Luting Cements and Oral Bacteria Linked to Peri-Implant Disease: An In Vitro Analysis of Planktonic and Biofilm Growth--A Preliminary Study.

PubMed

Raval, Neal C; Wadhwani, Chandur P K; Jain, Sumita; Darveau, Richard P

2015-12-01

There is little consensus on the most appropriate cement to use when restoring a cement-retained, implant-supported restoration. One consideration should be the interaction of pathogenic oral bacteria with restorative cements. To determine how oral bacteria associated with peri-implant disease grow in the presence of implant cements. Five test cements with varying composition (zinc oxide-eugenol [TBO], eugenol-free zinc oxide [TBNE], zinc orthophosphate [FL], and two resin cements [PIC and ML]) were used to fabricate specimen disks. The disks were submerged in bacterial suspensions of either Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, or Porphyromonas gingivalis. Planktonic bacterial growth within the test media was measured by determining the optical density of the cultures (OD600 ). Positive controls (media and bacteria without cement disks) and negative controls (media alone) were similarly evaluated. The mean and standard deviations (SD) were calculated for planktonic growth from three separate experiments. ANOVA statistical analysis with post hoc Tukey tests was performed where differences existed (p < .05). Selected cement disks (TBO and ML) were further examined for bacterial biofilm growth. Surface bacteria were removed and grown on agar media, and colony-forming units (CFUs) were quantified. Planktonic growth for both A. actinomycetemcomitans and P. gingivalis was significantly inhibited (p < .05) when grown in the presence of cement disks consisting of TBNE, PIC, FL, and TBO. In contrast, neither of these bacteria displayed growth inhibition in the presence of ML cement disks. F. nucleatum growth was also significantly inhibited by PIC, FL. and TBO (p < .05), but not by ML and TBNE cement disks. CFU counts for the biofilm study for TBO gave minimal and, in some instances, no bacterial adherence and growth, in contrast to ML, which supported substantially greater bacterial biofilm growth. Cements display differing abilities to

Periodontopathogens and human β-defensin-2 expression in gingival crevicular fluid from patients with periodontal disease in Guangxi, China.

PubMed

Yong, X; Chen, Y; Tao, R; Zeng, Q; Liu, Z; Jiang, L; Ye, L; Lin, X

2015-06-01

Periodontal diseases are often induced by periodontopathogens, which are always exposed to certain innate immune factors in gingival crevicular fluid, including human β-defensin-2 (hBD-2). This study aims to investigate the relationship among periodontopathogens, clinical parameters and hBD-2 expression. Thirty-two healthy controls, 42 patients with chronic gingivitis and 95 patients with chronic periodontitis were recruited in Guangxi, China. Bleeding index, probing depth and clinical attachment level were measured for all teeth including mesiobuccal, buccal, disobuccal, mesiolingual, lingual, disolingual six sites of all patient. Gingival crevicular fluid samples were collected from the study sites. The prevalence and copy numbers (CN) of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, Tannerella forsythia and total bacteria in gingival crevicular fluid were quantified by real-time PCR. The hBD-2 concentration in gingival crevicular fluid was measured by ELISA. Both the prevalence and the CN of A. actinomycetemcomitans, P. gingivalis, T. denticola and T. forsythia were higher in patients with chronic periodontitis than in healthy controls and patients with chronic gingivitis; however, there was no significant difference in the prevalence of P. intermedia among the three study groups, and the highest CN was found in patients with chronic gingivitis, rather than in patients with chronic periodontitis. The loads of P. gingivalis, P. intermedia, T. denticola and total bacteria were positively related to probing depth, bleeding index and clinical attachment level. The concentration of hBD-2 in gingival crevicular fluid was higher in patients with chronic gingivitis and in patients with chronic periodontitis than in healthy controls. In addition, the hBD-2 concentration was positively related to the CN of P. gingivalis, T. forsythia and total bacteria, as well as to bleeding index and probing depth. The

Characterization of the First Molluscicidal Lipopolysaccharide from Moraxella osloensis

PubMed Central

Tan, Li; Grewal, Parwinder S.

2003-01-01

Moraxella osloensis is a bacterium that is mutualistically associated with Phasmarhabditis hermaphrodita, a nematode that has potential for the biocontrol of mollusk pests, especially the slug Deroceras reticulatum. We discovered that purified M. osloensis lipopolysaccharide (LPS) possesses a lethal toxicity to D. reticulatum when administered by injection but no contact or oral toxicity to this slug. The toxicity of the LPS resides in the lipid A moiety. M. osloensis LPS was semiquantitated at 6 × 107 endotoxin units per mg. The LPS is a rough-type LPS with an estimated molecular weight of 5,300. Coinjection of galactosamine with the LPS increased the LPS's toxicity to the slug two- to four-fold. The galactosamine-induced sensitization of the slug to the LPS was reversed completely by uridine. PMID:12788774

Characterization of the first molluscicidal lipopolysaccharide from Moraxella osloensis.

PubMed

Tan, Li; Grewal, Parwinder S

2003-06-01

Moraxella osloensis is a bacterium that is mutualistically associated with Phasmarhabditis hermaphrodita, a nematode that has potential for the biocontrol of mollusk pests, especially the slug Deroceras reticulatum. We discovered that purified M. osloensis lipopolysaccharide (LPS) possesses a lethal toxicity to D. reticulatum when administered by injection but no contact or oral toxicity to this slug. The toxicity of the LPS resides in the lipid A moiety. M. osloensis LPS was semiquantitated at 6 x 10(7) endotoxin units per mg. The LPS is a rough-type LPS with an estimated molecular weight of 5,300. Coinjection of galactosamine with the LPS increased the LPS's toxicity to the slug two- to four-fold. The galactosamine-induced sensitization of the slug to the LPS was reversed completely by uridine.

Systemic inflammatory response and serum lipopolysaccharide levels predict multiple organ failure and death in alcoholic hepatitis.

PubMed

Michelena, Javier; Altamirano, José; Abraldes, Juan G; Affò, Silvia; Morales-Ibanez, Oriol; Sancho-Bru, Pau; Dominguez, Marlene; García-Pagán, Juan Carlos; Fernández, Javier; Arroyo, Vicente; Ginès, Pere; Louvet, Alexandre; Mathurin, Philippe; Mehal, Wajahat Z; Caballería, Juan; Bataller, Ramón

2015-09-01

Alcoholic hepatitis (AH) frequently progresses to multiple organ failure (MOF) and death. However, the driving factors are largely unknown. At admission, patients with AH often show criteria of systemic inflammatory response syndrome (SIRS) even in the absence of an infection. We hypothesize that the presence of SIRS may predispose to MOF and death. To test this hypothesis, we studied a cohort including 162 patients with biopsy-proven AH. The presence of SIRS and infections was assessed in all patients, and multivariate analyses identified variables independently associated with MOF and 90-day mortality. At admission, 32 (19.8%) patients were diagnosed with a bacterial infection, while 75 (46.3%) fulfilled SIRS criteria; 58 patients (35.8%) developed MOF during hospitalization. Short-term mortality was significantly higher among patients who developed MOF (62.1% versus 3.8%, P < 0.001). The presence of SIRS was a major predictor of MOF (odds ratio = 2.69, P = 0.025) and strongly correlated with mortality. Importantly, the course of patients with SIRS with and without infection was similar in terms of MOF development and short-term mortality. Finally, we sought to identify serum markers that differentiate SIRS with and without infection. We studied serum levels of high-sensitivity C-reactive protein, procalcitonin, and lipopolysaccharide at admission. All of them predicted mortality. Procalcitonin, but not high-sensitivity C-reactive protein, serum levels identified those patients with SIRS and infection. Lipopolysaccharide serum levels predicted MOF and the response to prednisolone. In the presence or absence of infections, SIRS is a major determinant of MOF and mortality in AH, and the mechanisms involved in the development of SIRS should be investigated; procalcitonin serum levels can help to identify patients with infection, and lipopolysaccharide levels may help to predict mortality and the response to steroids. © 2015 by the American Association

Reliability of plasma lipopolysaccharide-binding protein (LBP) from repeated measures in healthy adults.

PubMed

Citronberg, Jessica S; Wilkens, Lynne R; Lim, Unhee; Hullar, Meredith A J; White, Emily; Newcomb, Polly A; Le Marchand, Loïc; Lampe, Johanna W

2016-09-01

Plasma lipopolysaccharide-binding protein (LBP), a measure of internal exposure to bacterial lipopolysaccharide, has been associated with several chronic conditions and may be a marker of chronic inflammation; however, no studies have examined the reliability of this biomarker in a healthy population. We examined the temporal reliability of LBP measured in archived samples from participants in two studies. In Study one, 60 healthy participants had blood drawn at two time points: baseline and follow-up (either three, six, or nine months). In Study two, 24 individuals had blood drawn three to four times over a seven-month period. We measured LBP in archived plasma by ELISA. Test-retest reliability was estimated by calculating the intraclass correlation coefficient (ICC). Plasma LBP concentrations showed moderate reliability in Study one (ICC 0.60, 95 % CI 0.43-0.75) and Study two (ICC 0.46, 95 % CI 0.26-0.69). Restricting the follow-up period improved reliability. In Study one, the reliability of LBP over a three-month period was 0.68 (95 % CI: 0.41-0.87). In Study two, the ICC of samples taken ≤seven days apart was 0.61 (95 % CI 0.29-0.86). Plasma LBP concentrations demonstrated moderate test-retest reliability in healthy individuals with reliability improving over a shorter follow-up period.

Murine P-glycoprotein deficiency alters intestinal injury repair and blunts lipopolysaccharide-induced radioprotection.

PubMed

Staley, Elizabeth M; Yarbrough, Vanisha R; Schoeb, Trenton R; Daft, Joseph G; Tanner, Scott M; Steverson, Dennis; Lorenz, Robin G

2012-09-01

P-glycoprotein (P-gp) has been reported to increase stem cell proliferation and regulate apoptosis. Absence of P-gp results in decreased repair of intestinal epithelial cells after chemical injury. To further explore the mechanisms involved in the effects of P-gp on intestinal injury and repair, we used the well-characterized radiation injury model. In this model, injury repair is mediated by production of prostaglandins (PGE(2)) and lipopolysaccharide (LPS) has been shown to confer radioprotection. B6.mdr1a(-/-) mice and wild-type controls were subjected to 12 Gy total body X-ray irradiation and surviving crypts in the proximal jejunum and distal colon were evaluated 3.5 days after irradiation. B6.mdr1a(-/-) mice exhibited normal baseline stem cell proliferation and COX dependent crypt regeneration after irradiation. However, radiation induced apoptosis was increased and LPS-induced radioprotection was blunted in the C57BL6.mdr1a(-/-) distal colon, compared to B6 wild-type controls. The LPS treatment induced gene expression of the radioprotective cytokine IL-1α, in B6 wild-type controls but not in B6.mdr1a(-/-) animals. Lipopolysaccharid-induced radioprotection was absent in IL-1R1(-/-) animals, indicating a role for IL-1α in radioprotection, and demonstrating that P-gp deficiency interferes with IL-1α gene expression in response to systemic exposure to LPS.

In vitro toxicity and interactions of environmental contaminants (Arochlor 1254 and mercury) and immunomodulatory agents (lipopolysaccharide and cortisol) on thymocytes from lake trout (Salvelinus namaycush)

USGS Publications Warehouse

Miller, Gregory G.; Sweet, Leonard I.; Adams, Jean V.; Omann, Geneva M.; Passino-Reader, Dora R.; Meier, Peter G.

2002-01-01

The immunotoxicity of chemical combinations commonly encountered by the lake trout (Salvelinus namaycush) immune system was the focus of this study. It was hypothesised that combinations of an environmental contaminant (mercuric chloride or Aroclor 1254) and an immunomodulatory agent (bacterial endotoxin or cortisol) might interact to produce a greater toxicity than that of the environmental contaminant alone at concentrations typically encountered in piscine blood and other tissues. Thus lake trout thymocytes were isolated and treated with mercuric chloride or Aroclor 1254 in the presence and absence of cortisol or lipopolysaccharide. Incubations were performed for 6 or 20 h at 4° C or 10° C. Lipopolysaccharide did not affect the toxicity of either contaminant. In contrast, cortisol enhanced the toxicity of both environmental contaminants. Hence, stressors that lead to increased cortisol production, but not lipopolysaccharide directly, may increase the toxicity of mercury and Aroclor 1254 to lake trout thymocytes.

Enhancement of ligand-dependent down-regulation of glucocorticoid receptor by lipopolysaccharide.

PubMed

Hirasawa, Noriyasu; Yashima, Kazushi; Ishihara, Kenji

2009-10-07

The inhibitory actions of glucocorticoids are often attenuated in inflamed tissues. The aim of the present study was to investigate whether the dexamethasone-induced downregulation of glucocorticoid receptor (GR) expression was enhanced by the stimulation with lipopolysaccharide (LPS). Various cells were stimulated with LPS (1microg/ml) for 30min and then treated with dexamethasone (1microM) for specified periods. The levels of GR and the phosphorylation at Ser211 were determined by Western blot. The effects of kinase inhibitors and a proteasome inhibitor on them were examined. The treatment of NCI-H292 cells with dexamethasone reduced the levels of GR, and the pretreatment with LPS accelerated the reduction. Such an enhancement by LPS of the dexamethasone-induced downregulation was observed in the respiratory epithelial cell lines BEAS-2B and A549, but not in the keratinocyte-like cell line HaCaT, the hematopoietic cell lines U937, THP-1 and Eol-1, or in hepatocytoma HepG2 cells. The treatment with dexamethasone and LPS apparently decreased GR levels in the lungs of BALB/c mice but not in the liver. In NCI-H292 cells, the LPS-enhanced downregulation of GR expression was recovered by the proteasome inhibitor MG-132. SP600125, SB203580 and roscovitine but not U0126 inhibited the LPS-induced enhancement of both the phosphorylation and the downregulation of GR. These findings suggested that the ligand-dependent downregulation of GR expression via the proteasome was apparent in the respiratory epithelial cells and enhanced by lipopolysaccharide via the activation of p38 MAP kinase, c-Jun N-terminal kinase and cyclin-dependent kinases.

Suppression of lipopolysaccharide-stimulated cytokine/chemokine production in skin cells by sandalwood oils and purified α-santalol and β-santalol.

PubMed

Sharma, M; Levenson, C; Bell, R H; Anderson, S A; Hudson, J B; Collins, C C; Cox, M E

2014-06-01

Medicinally, sandalwood oil (SO) has been attributed with antiinflammatory properties; however, mechanism(s) for this activity have not been elucidated. To examine how SOs affect inflammation, cytokine antibody arrays and enzyme-linked immunosorbent assays were used to assess changes in production of cytokines and chemokines by co-cultured human dermal fibroblasts and neo-epidermal keratinocytes exposed to lipopolysaccharides and SOs from Western Australian and East Indian sandalwood trees or to the primary SO components, α-santalol and β-santalol. Lipopolysaccharides stimulated the release of 26 cytokines and chemokines, 20 of which were substantially suppressed by simultaneous exposure to either of the two sandalwood essential oils and to ibuprofen. The increased activity of East Indian SO correlated with increased santalol concentrations. Purified α-santalol and β-santalol equivalently suppressed production of five indicator cytokines/chemokines at concentrations proportional to the santalol concentrations of the oils. Purified α-santalol and β-santalol also suppressed lipopolysaccharide-induced production of the arachidonic acid metabolites, prostaglandin E2, and thromboxane B2, by the skin cell co-cultures. The ability of SOs to mimic ibuprofen non-steroidal antiinflammatory drugs that act by inhibiting cyclooxygenases suggests a possible mechanism for the observed antiinflammatory properties of topically applied SOs and provides a rationale for use in products requiring antiinflammatory effects. Copyright © 2013 John Wiley & Sons, Ltd.

Insulin-like growth factor-I gene delivery to astrocytes reduces their inflammatory response to lipopolysaccharide

PubMed Central

2011-01-01

Background Insulin-like growth factor-I (IGF-I) exerts neuroprotective actions in the central nervous system that are mediated at least in part by control of activation of astrocytes. In this study we have assessed the efficacy of exogenous IGF-I and IGF-I gene therapy in reducing the inflammatory response of astrocytes from cerebral cortex. Methods An adenoviral vector harboring the rat IGF-I gene and a control adenoviral vector harboring a hybrid gene encoding the herpes simplex virus type 1 thymidine kinase fused to Aequorea victoria enhanced green fluorescent protein were used in this study. Primary astrocytes from mice cerebral cortex were incubated for 24 h or 72 h with vehicle, IGF-I, the IGF-I adenoviral vector, or control vector; and exposed to bacterial lipopolysaccharide to induce an inflammatory response. IGF-I levels were measured by radioimmunoassay. Levels of interleukin 6, tumor necrosis factor-α, interleukin-1β and toll-like receptor 4 mRNA were assessed by quantitative real-time polymerase chain reaction. Levels of IGF-I receptor and IGF binding proteins 2 and 3 were assessed by western blotting. The subcellular distribution of nuclear factor κB (p65) was assessed by immunocytochemistry. Statistical significance was assessed by one way analysis of variance followed by the Bonferroni pot hoc test. Results IGF-I gene therapy increased IGF-I levels without affecting IGF-I receptors or IGF binding proteins. Exogenous IGF-I, and IGF-I gene therapy, decreased expression of toll-like receptor 4 and counteracted the lipopolysaccharide-induced inflammatory response of astrocytes. In addition, IGF-I gene therapy decreased lipopolysaccharide-induced translocation of nuclear factor κB (p65) to the cell nucleus. Conclusion These findings demonstrate efficacy of exogenous IGF-I and of IGF-I gene therapy in reducing the inflammatory response of astrocytes. IGF-I gene therapy may represent a new approach to reduce inflammatory reactions in glial cells. PMID

Anti-inflammatory activity of hydroxycinnamic acid derivtives isolated from corn bran in lipopolysaccharide-stimulated raw 264.7 macrophages

USDA-ARS?s Scientific Manuscript database

In this study, the effect of the 80 percent ethanolic extract of corn bran (EECB) on inhibition of nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated Raw 264.7 cells was investigated. The EECB inhibited LPS induced NO production...

Murine P-glycoprotein Deficiency Alters Intestinal Injury Repair and Blunts Lipopolysaccharide-Induced Radioprotection

PubMed Central

Staley, Elizabeth M.; Yarbrough, Vanisha R.; Schoeb, Trenton R.; Daft, Joseph G.; Tanner, Scott M.; Steverson, Dennis; Lorenz, Robin G.

2012-01-01

P-glycoprotein (P-gp) has been reported to increase stem cell proliferation and regulate apoptosis. Absence of P-gp results in decreased repair of intestinal epithelial cells after chemical injury. To further explore the mechanisms involved in the effects of P-gp on intestinal injury and repair, we used the well-characterized radiation injury model. In this model, injury repair is mediated by production of prostaglandins (PGE2) and lipopolysaccharide (LPS) has been shown to confer radioprotection. B6.mdr1a−/− mice and wild-type controls were subjected to 12 Gy total body X-ray irradiation and surviving crypts in the proximal jejunum and distal colon were evaluated 3.5 days after irradiation. B6.mdr1a−/−mice exhibited normal baseline stem cell proliferation and COX dependent crypt regeneration after irradiation. However, radiation induced apoptosis was increased and LPS-induced radioprotection was blunted in the C57BL6.mdr1a−/−distal colon, compared to B6 wild-type controls. The LPS treatment induced gene expression of the radioprotective cytokine IL-1α, in B6 wild-type controls but not in B6.mdr1a−/− animals. Lipopolysaccharid-induced radioprotection was absent in IL-1R1−/− animals, indicating a role for IL-1α in radioprotection, and demonstrating that P-gp deficiency interferes with IL-1α gene expression in response to systemic exposure to LPS. PMID:22780103

Cytochrome P4502E1 inhibitor, chlormethiazole, decreases lipopolysaccharide-induced inflammation in rat Kupffer cells with ethanol treatment

USDA-ARS?s Scientific Manuscript database

To investigate the role of Cytochrome P4502E1 in sensitizing Kupffer cells to lipopolysaccharide (LPS)-mediated inflammation after ethanol induction. Sprague-Dawley rats were fed a liquid ethanol diet, control diet or ethanol diet supplemented with CYP2E1 inhibitor, chlormethiazole (CMZ), for 4'week...

Supplementation with a Lactobacillus acidophilus fermentation product alters the metabolic response following a lipopolysaccharide challenge in weaned pigs

USDA-ARS?s Scientific Manuscript database

This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would alter the metabolic response following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4+/-0.1 kg BW) were housed individually with ad libitum access to feed and water. Pigs were...

Supplementation of Lactobacillus acidophilus fermentation product can attenuate the acute phase response following a lipopolysaccharide challenge in pigs.

USDA-ARS?s Scientific Manuscript database

This study was designed to determine if feeding a Lactobacillus acidophilus fermentation product to weaned pigs would reduce stress and acute phase responses (APR) following a lipopolysaccharide (LPS) challenge. Pigs (n=30; 6.4±0.1 kilograms body weight) were housed individually in pens with ad libi...

Choline Supplementation During Pregnancy Protects Against Gestational Lipopolysaccharide-Induced Inflammatory Responses.

PubMed

Zhang, Min; Han, Xinjia; Bao, Juejie; Yang, Jinying; Shi, Shao-Qing; Garfield, Robert E; Liu, Huishu

2018-01-01

To estimate the effects and mechanisms of choline, an essential nutrient and a selective α7 nicotinic acetylcholine receptor (α7nAChR) agonist, on the prevention of symptoms and the effects on the cholinergic anti-inflammatory pathways (CAP) in a lipopolysaccharide (LPS)-induced inflammatory response in a rat model. Inflammation was induced by LPS treatment (1.0 μg LPS/kg body weight) on gestational day (GD) 14. Nonpregnant and pregnant Sprague Dawley rats were placed on a normal choline diet (1.1 g/kg) or supplemented choline diet (5.0 g/kg) from GDs 1 to 20. Systolic blood pressure (SBP), urinary albumin, and pregnancy outcomes were recorded. On GD 20, serum and placentas were assayed for cytokines. Western blots were used to determine the expression of placenta α7nAChR and components of the α7nAChR-CAP, including nuclear factor-κB (NF-κB) and protein kinase B (AKT). Immunohistochemistry was used to localize placental sites for the p65 subunit of NF-κB. Lipopolysaccharide significantly increased SBP and urinary albumin and decreased pregnancy outcomes, and these effects were partially reversed by higher choline treatment. Choline supplementation also significantly attenuated the LPS-induced increase in serum and placental inflammatory cytokines, decreased the expression of placental α7nAChR, lowered the activation of NF-κB signaling in placenta mononuclear cells, and inhibited placental AKT phosphorylation. This study confirms that LPS induces inflammatory conditions in pregnant rats and shows that choline supplementation protects against the inflammatory symptoms through its action on α7nAChR and CAP. These observations have important implications for the prevention and treatment of inflammatory responses associated with pregnancy.

A novel podocyte gene, semaphorin 3G, protects glomerular podocyte from lipopolysaccharide-induced inflammation.

PubMed

Ishibashi, Ryoichi; Takemoto, Minoru; Akimoto, Yoshihiro; Ishikawa, Takahiro; He, Peng; Maezawa, Yoshiro; Sakamoto, Kenichi; Tsurutani, Yuya; Ide, Shintaro; Ide, Kana; Kawamura, Harukiyo; Kobayashi, Kazuki; Tokuyama, Hirotake; Tryggvason, Karl; Betsholtz, Christer; Yokote, Koutaro

2016-05-16

Kidney diseases including diabetic nephropathy have become huge medical problems, although its precise mechanisms are still far from understood. In order to increase our knowledge about the patho-physiology of kidney, we have previously identified >300 kidney glomerulus-enriched transcripts through large-scale sequencing and microarray profiling of the mouse glomerular transcriptome. One of the glomerulus-specific transcripts identified was semaphorin 3G (Sema3G) which belongs to the semaphorin family. The aim of this study was to analyze both the in vivo and in vitro functions of Sema3G in the kidney. Sema3G was expressed in glomerular podocytes. Although Sema3G knockout mice did not show obvious glomerular defects, ultrastructural analyses revealed partially aberrant podocyte foot processes structures. When these mice were injected with lipopolysaccharide to induce acute inflammation or streptozotocin to induce diabetes, the lack of Sema3G resulted in increased albuminuria. The lack of Sema3G in podocytes also enhanced the expression of inflammatory cytokines including chemokine ligand 2 and interleukin 6. On the other hand, the presence of Sema3G attenuated their expression through the inhibition of lipopolysaccharide-induced Toll like receptor 4 signaling. Taken together, our results surmise that the Sema3G protein is secreted by podocytes and protects podocytes from inflammatory kidney diseases and diabetic nephropathy.

A novel podocyte gene, semaphorin 3G, protects glomerular podocyte from lipopolysaccharide-induced inflammation

PubMed Central

Ishibashi, Ryoichi; Takemoto, Minoru; Akimoto, Yoshihiro; Ishikawa, Takahiro; He, Peng; Maezawa, Yoshiro; Sakamoto, Kenichi; Tsurutani, Yuya; Ide, Shintaro; Ide, Kana; Kawamura, Harukiyo; Kobayashi, Kazuki; Tokuyama, Hirotake; Tryggvason, Karl; Betsholtz, Christer; Yokote, Koutaro

2016-01-01

Kidney diseases including diabetic nephropathy have become huge medical problems, although its precise mechanisms are still far from understood. In order to increase our knowledge about the patho-physiology of kidney, we have previously identified >300 kidney glomerulus-enriched transcripts through large-scale sequencing and microarray profiling of the mouse glomerular transcriptome. One of the glomerulus-specific transcripts identified was semaphorin 3G (Sema3G) which belongs to the semaphorin family. The aim of this study was to analyze both the in vivo and in vitro functions of Sema3G in the kidney. Sema3G was expressed in glomerular podocytes. Although Sema3G knockout mice did not show obvious glomerular defects, ultrastructural analyses revealed partially aberrant podocyte foot processes structures. When these mice were injected with lipopolysaccharide to induce acute inflammation or streptozotocin to induce diabetes, the lack of Sema3G resulted in increased albuminuria. The lack of Sema3G in podocytes also enhanced the expression of inflammatory cytokines including chemokine ligand 2 and interleukin 6. On the other hand, the presence of Sema3G attenuated their expression through the inhibition of lipopolysaccharide-induced Toll like receptor 4 signaling. Taken together, our results surmise that the Sema3G protein is secreted by podocytes and protects podocytes from inflammatory kidney diseases and diabetic nephropathy. PMID:27180624

Heme oxygenase-1 induction alters chemokine regulation and ameliorates human immunodeficiency virus-type-1 infection in lipopolysaccharide-stimulated macrophages

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Zhao-Hua; Kumari, Namita; Nekhai, Sergei

2013-06-07

Highlights: •Lipopolysaccharide stimulation of heme oxygenase-1 (HO-1) ameliorated HIV-1 infection of primary human macrophages. •The partial protection by HO-1 against HIV infection was associated with induction of chemokines such as MIP1α and MIP1β. •This mechanism explains lipopolysaccharide-stimulated HO-1-mediated inhibition of HIV-1 infection of macrophages. -- Abstract: We have elucidated a putative mechanism for the host resistance against HIV-1 infection of primary human monocyte-derived macrophages (MDM) stimulated with lipopolysaccharide (LPS). We show that LPS-activated MDM both inhibited HIV-1 entry into the cells and were refractory to post-entry productive viral replication. LPS-treated cells were virtually negative for mature virions as revealed bymore » transmission electron microscopy. LPS activation of MDM markedly enhanced the expression of heme oxygenase-1 (HO-1), a potent inducible cytoprotective enzyme. Increased HO-1 expression was accompanied by elevated production of macrophage inflammatory chemokines (MIP1α and MIP1β) by LPS-activated MDM, significantly decreased surface chemokine receptor-5 (CCR-5) expression, and substantially reduced virus replication. Treatment of cells with HO-1 inhibitor SnPP IX (tin protoporphyrin IX) attenuated the LPS-mediated responses, HIV-1 replication and secretion of MIP1α, MIP1β, and LD78β chemokines with little change in surface CCR-5 expression. These results identify a novel role for HO-1 in the modulation of host immune response against HIV infection of MDM.« less

Peripheral arterial disease associated with caries and periodontal disease.

PubMed

Soto-Barreras, Uriel; Olvera-Rubio, Javier O; Loyola-Rodriguez, Juan P; Reyes-Macias, Juan F; Martinez-Martinez, Rita E; Patiño-Marin, Nuria; Martinez-Castañon, Gabriel A; Aradillas-Garcia, Celia; Little, James W

2013-04-01

Peripheral arterial disease (PAD) is an important cardiovascular disorder of the peripheral arteries. Chronic infections, such as periodontitis, may play an important role in the etiology and pathophysiology of PAD and other cardiovascular conditions. Recently, Streptococcus mutans has been found with high frequency in atheromatous plaques. The aim of this study is to evaluate the possible clinical and microbiologic association between PAD and periodontitis and dental caries. Thirty patients with PAD and 30 control individuals were selected. PAD and its severity were established by the use of the ankle-brachial index (ABI). Clinical attachment loss (AL); probing depth; decayed, missing, and filled teeth (DMFT) index; and C-reactive protein (CRP) levels were evaluated. The presence of bacterial DNA from Streptococcus mutans, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Treponema denticola, and Aggregatibacter actinomycetemcomitans was identified by polymerase chain reaction in subgingival biofilm and serum. Patients with ≥30% AL ≥ 4 mm had six-fold increased risk of having PAD (odds ratio = 8.18; 95% confidence interval = 1.21 to 35.23; P = 0.031). There was statistical difference in the CRP (P = 0.0413) and DMFT index (P = 0.0002), with elevated number of missing teeth (P = 0.0459) in the PAD group compared with the control group. There were no significant differences in the frequency of bacteria in serum and subgingival plaque. There was a positive relationship between periodontitis based on AL and PAD determined by the ABI (odds ratio = 8.18).

Occurrence of periodontal pathogens in ethnic groups from a native Brazilian reservation.

PubMed

Gaetti-Jardim, Elerson; Pereira, Maurício Fabiano; Vieira, Evanice Menezes Marçal; Schweitzer, Christiane Marie; Okamoto, Ana Cláudia; Ávila-Campos, Mario J

2015-06-01

The present study was designed to evaluate the occurrence of periodontal pathogens in the subgingival biofilm of 100 native Brazilians living at the Umutina Indian Reservation, Mato Grosso State, Brazil. Periodontal clinical examinations were carried out prior to collection of subgingival biofilm, and the presence of 14 periodontal microorganisms was evaluated by polymerase chain reaction (PCR). The prevalence and risk analysis was performed using Cochran and Mantel-Haenszel statistics for dichotomous variables or Pearson's chi-squared test for analysis of proportions when variables had three or more categories. The interrelations between clinical and microbiological parameters were assessed using Fisher's exact test and the Mann-Whitney U test. Individuals with chronic periodontitis were frequently colonized by the association between Porphyromonas gingivalis and Campylobacter rectus, P. gingivalis and Prevotella intermedia, or P. gingivalis and Tannerella forsythia. Patients with chronic periodontitis were also colonized by Porphyromonas gulae and P. intermedia or by the association between P. gulae and T. forsythia. P. gulae was detected only in the subgingival samples from natives on a traditional diet. Gingival bleeding was associated with Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, T. forsythia, P. gingivalis, P. gulae, Porphyromonas endodontalis, P. intermedia, and Prevotella nigrescens. Treponema denticola was uncommon. Peculiar microbiota was demonstrated to be associated with different periodontal disease statuses in native Brazilians, with modest occurrence of certain pathogens, such as T. denticola, and the presence of P. gulae in natives with gingivitis or chronic periodontitis. Copyright © 2015. Published by Elsevier Ltd.

Tannerella forsythia and the HLA-DQB1 allele are associated with susceptibility to periodontal disease in Japanese adolescents.

PubMed

Shimomura-Kuroki, Junko; Yamashita, Kie; Shimooka, Shohachi

2009-01-01

Periodontal disease is a multiple factor disease caused by genetic factors, environmental factors, and periodontal bacteria (periodontal pathogens). The present study aimed to elucidate the risk factors for periodontal disease in Japanese adolescents. Subjects (11-16 years old) were classified into three groups: localized aggressive periodontitis (LAP), periodontal attachment loss (PAL), and periodontally healthy (PH) groups. Genomic DNA isolated from the buccal mucosa was used for single-nucleotide polymorphism analyses of the candidate genes (interleukin-1alpha-889; interleukin-1alpha +4845; interleukin-1beta +3954; an immunoglobulin G Fc gamma receptor, FcgammaRIIa-R/H131; and a human leukocyte antigen class II allele, HLA-DQB1) of aggressive periodontitis. Subgingival plaque samples obtained from the same subjects were used for 16S rRNAbased polymerase chain reaction analysis of five important periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Tannerella forsythia). Tannerella forsythia was detected in the deepest periodontal pockets in all subjects in the LAP and PAL groups. The prevalence of an atypical BamHI restriction site in HLA-DQB1 of the LAP group was significantly higher than that in the PH and PAL groups. Furthermore, all subjects who had the atypical BamHI restriction site in HLA-DQB1 had T. forsythia infection. These results suggested that T. forsythia is associated with periodontal disease in Japanese adolescents and also suggested that HLA-DQB1 is related to LAP and is associated with T. forsythia infection.

Nucleases from Prevotella intermedia can degrade neutrophil extracellular traps.

PubMed

Doke, M; Fukamachi, H; Morisaki, H; Arimoto, T; Kataoka, H; Kuwata, H

2017-08-01

Periodontitis is an inflammatory disease caused by periodontal bacteria in subgingival plaque. These bacteria are able to colonize the periodontal region by evading the host immune response. Neutrophils, the host's first line of defense against infection, use various strategies to kill invading pathogens, including neutrophil extracellular traps (NETs). These are extracellular net-like fibers comprising DNA and antimicrobial components such as histones, LL-37, defensins, myeloperoxidase, and neutrophil elastase from neutrophils that disarm and kill bacteria extracellularly. Bacterial nuclease degrades the NETs to escape NET killing. It has now been shown that extracellular nucleases enable bacteria to evade this host antimicrobial mechanism, leading to increased pathogenicity. Here, we compared the DNA degradation activity of major Gram-negative periodontopathogenic bacteria, Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans. We found that Pr. intermedia showed the highest DNA degradation activity. A genome search of Pr. intermedia revealed the presence of two genes, nucA and nucD, putatively encoding secreted nucleases, although their enzymatic and biological activities are unknown. We cloned nucA- and nucD-encoding nucleases from Pr. intermedia ATCC 25611 and characterized their gene products. Recombinant NucA and NucD digested DNA and RNA, which required both Mg 2+ and Ca 2+ for optimal activity. In addition, NucA and NucD were able to degrade the DNA matrix comprising NETs. © 2016 The Authors Molecular Oral Microbiology Published by John Wiley & Sons Ltd.

RbsB (NTHI_0632) mediates quorum signal uptake in nontypeable Haemophilus influenzae strain 86-028NP

PubMed Central

Armbruster, Chelsie E.; Pang, Bing; Murrah, Kyle; Juneau, Richard A.; Perez, Antonia C.; Weimer, Kristin E.D.; Swords, W. Edward

2011-01-01

Summary Nontypeable Haemophilus influenzae (NTHI) is a respiratory commensal and opportunistic pathogen, which persists within biofilms on airway mucosal surfaces. For many species, biofilm formation is impacted by quorum signaling. Our prior work shows that production of autoinducer-2 (AI-2) promotes biofilm development and persistence for NTHI 86-028NP. NTHI 86-028NP encodes an ABC transporter annotated as a ribose transport system that includes a protein (RbsB) with similarity to the Escherichia coli LsrB and Aggregatibacter actinomycetemcomitans RbsB proteins that bind AI-2. In this study, inactivation of rbsB significantly reduced uptake of AI-2 and the AI-2 precursor dihydroxypentanedione (DPD) by NTHI 86-028NP. Moreover, DPD uptake was not competitively inhibited by ribose or other pentose sugars. Transcript levels of rbsB increased in response to DPD and as bacteria approached stationary-phase growth. The NTHI 86-028NP rbsB mutant also formed biofilms with significantly reduced thickness and total biomass and reduced surface phosphorylcholine, similar to a luxS mutant. Infection studies revealed that loss of rbsB impaired bacterial persistence in the chinchilla middle-ear, similar to our previous results with luxS mutants. Based on these data, we conclude that in NTHI 86-028NP, RbsB is a LuxS/AI-2 regulated protein that is required for uptake of and response to AI-2. PMID:21923771

RbsB (NTHI_0632) mediates quorum signal uptake in nontypeable Haemophilus influenzae strain 86-028NP.

PubMed

Armbruster, Chelsie E; Pang, Bing; Murrah, Kyle; Juneau, Richard A; Perez, Antonia C; Weimer, Kristin E D; Swords, W Edward

2011-11-01

Nontypeable Haemophilus influenzae (NTHI) is a respiratory commensal and opportunistic pathogen, which persists within biofilms on airway mucosal surfaces. For many species, biofilm formation is impacted by quorum signalling. Our prior work shows that production of autoinducer-2 (AI-2) promotes biofilm development and persistence for NTHI 86-028NP. NTHI 86-028NP encodes an ABC transporter annotated as a ribose transport system that includes a protein (RbsB) with similarity to the Escherichia coli LsrB and Aggregatibacter actinomycetemcomitans RbsB proteins that bind AI-2. In this study, inactivation of rbsB significantly reduced uptake of AI-2 and the AI-2 precursor dihydroxypentanedione (DPD) by NTHI 86-028NP. Moreover, DPD uptake was not competitively inhibited by ribose or other pentose sugars. Transcript levels of rbsB increased in response to DPD and as bacteria approached stationary-phase growth. The NTHI 86-028NP rbsB mutant also formed biofilms with significantly reduced thickness and total biomass and reduced surface phosphorylcholine, similar to a luxS mutant. Infection studies revealed that loss of rbsB impaired bacterial persistence in the chinchilla middle ear, similar to our previous results with luxS mutants. Based on these data, we conclude that in NTHI 86-028NP, RbsB is a LuxS/AI-2 regulated protein that is required for uptake of and response to AI-2. © 2011 Blackwell Publishing Ltd.

Periodontal conditions during the pregnancy associated with periodontal pathogens.

PubMed

Usin, Maria Matilde; Tabares, Sandra M; Parodi, Ricardo J; Sembaj, Adela

2013-02-01

To describe the bacterial associations in the periodontal pockets of pregnant women and to correlate the presence of Prevotella intermedia, Tannerella forsythia (T. forsythia), Treponema denticola (T. denticola), Aggregatibacter actinomycetemcomitans, and Porphyromona gingivalis (P. gingivalis) with periodontal parameters of severity. The analysis was performed with 150 pregnant women. The examination consisted of an evaluation of bleeding, suppuration, probing depths, clinical attachment levels, hypermobility scores, the Silness and Löe Plaque Index, and the Löe and the Silness Gingival Index. Each periodontal pathogen was identified by polymerase chain reaction. A statistically-significant association was observed (P < 0.01) between P. gingivalis and T. forsythia, between P. gingivalis and T. denticola, and between T. forsythia and T. denticola. Age was observed to be a risk factor in the development of moderate periodontitis (odds ratio [OR] = 4.92, 95% confidence interval [CI] = 1.1-21.3, P = 0.0328). Age was significantly associated with increased pocket depth and plaque index (OR = 6.36, 95% CI = 1.8-22.2, P = 0.0037). In pregnant women, the presence of P. gingivalis was found to increase the risk of developing a clinical attachment level ≥ 5 mm. A high prevalence of P. gingivalis in pregnant women, especially in combination with T. forsythia and T. denticola, was associated with an increased risk of developing moderate periodontitis, and that association was more marked in pregnant women aged 30 years or older. © 2012 Wiley Publishing Asia Pty Ltd.

Subgingival air-polishing with erythritol during periodontal maintenance

PubMed Central

Müller, Nada; Moëne, Raphaël; Cancela, José A; Mombelli, Andrea

2014-01-01

Objectives To evaluate repeated subgingival air-polishing in residual pockets with a new erythritol powder containing 0.3% chlorhexidine. Material and Methods Single-centre, examiner masked, randomized clinical trial of 12 months with a two-arm, within-subject parallel design. Fifty patients in periodontal maintenance were monitored in 3-month intervals. At months 0, 3, 6 and 9, all sites presenting with a probing depth (PD) >4 mm were subject to subgingival air-polishing (test side) or ultrasonic debridement (control side). The primary endpoint was presence/absence of PD >4 mm after 12 months. Results Totally 6918 sites were monitored at baseline, 457 of them had a PD >4 mm (range 5–9 mm). The number of pockets >4 mm per subject, PD and bleeding on probing were significantly lower at month 12. Differences between test and control were not significant. There was a significant difference in favour of air-polishing for the perception of pain/discomfort. Differences of frequencies at >1000 and >100,000 cells/ml of six microorganisms between baseline and month 12 were not significant. At month 12, test sites were less frequently positive for Aggregatibacter actinomycetemcomitans at >1000 cells/ml than controls, and counts never exceeded 100,000 cells/ml. Conclusions Repeated subgingival air-polishing reduced the number of pockets >4 mm similar to ultrasonic debridement. It was safe and induced less pain. PMID:25041441

Efficacy of chlorhexidine digluconate-containing formulations and other mouthrinses against periodontopathogenic microorganisms.

PubMed

Eick, Sigrun; Goltz, Susann; Nietzsche, Sandor; Jentsch, Holger; Pfister, Wolfgang

2011-09-01

To determine in vitro the action of chlorhexidine digluconate and different commercially available mouthrinses on oral microorganisms. Minimal inhibitory concentrations and possible induction of resistance by chlorhexidine digluconate, an essential oil-containing mouthwash and an amine fluoride/stannous fluoride solution, were determined against microorganisms normally found in the oral cavity (10 streptococci, 2 enterobacteria, 1 Candida albicans, 8 Porphyromonas gingivalis, 6 Aggregatibacter actinomycetemcomitans, and 1 Fusobacterium nucleatum). Further, the effect of a 1-minute exposure on cell and bacterial viability was studied. The susceptibility of the oral microorganisms to chlorhexidine digluconate ranged from 0.01% to 0.50%. Passages on agar plates containing subinhibitory concentrations of chlorhexidine digluconate resulted in a transitory moderate increase in the tolerance to chlorhexidine digluconate in five of the 24 isolates. After 1 minute of exposure, chlorhexidine digluconate solutions as well as the essential oil and the amine/stannous fluoride-containing solutions showed a high activity against the tested microorganisms. Commercially available chlorhexidine digluconate formulations (ie, those with antidiscoloration systems) were partly less efficient than the corresponding manually prepared chlorhexidine digluconate preparation. The determination of MTT resulted in a strong cytotoxicity of all tested preparations to gingival fibroblasts. The results indicate that most of the chlorhexidine digluconate formulations as well as essential oil and the amine fluoride/stannous fluoride solutions are active against oral microbes. Long-term use of these agents would not result in emergent antimicrobial resistance.

Antimicrobial properties and dentin bonding strength of magnesium phosphate cements.

PubMed

Mestres, G; Abdolhosseini, M; Bowles, W; Huang, S-H; Aparicio, C; Gorr, S-U; Ginebra, M-P

2013-09-01

The main objective of this work was to assess the antimicrobial properties and the dentin-bonding strength of novel magnesium phosphate cements (MPC). Three formulations of MPC, consisting of magnesium oxide and a phosphate salt, NH4H2PO4, NaH2PO4 or a mixture of both, were evaluated. As a result of the setting reaction, MPC transformed into either struvite (MgNH4PO4·6H2O) when NH4H2PO4 was used or an amorphous magnesium sodium phosphate when NaH2PO4 was used. The MPC had appropriate setting times for hard tissue applications, high early compressive strengths and higher strength of bonding to dentin than commercial mineral trioxide aggregate cement. Bacteriological studies were performed with fresh and aged cements against three bacterial strains, Escherichia coli, Pseudomonas aeruginosa (planktonic and in biofilm) and Aggregatibacter actinomycetemcomitans. These bacteria have been associated with infected implants, as well as other frequent hard tissue related infections. Extracts of different compositions of MPC had bactericidal or bacteriostatic properties against the three bacterial strains tested. This was associated mainly with a synergistic effect between the high osmolarity and alkaline pH of the MPC. These intrinsic antimicrobial properties make MPC preferential candidates for applications in dentistry, such as root fillers, pulp capping agents and cavity liners. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

16S rDNA-based metagenomic analysis of dental plaque and lung bacteria in patients with severe acute exacerbations of chronic obstructive pulmonary disease.

PubMed

Tan, L; Wang, H; Li, C; Pan, Y

2014-12-01

Acute exacerbations of chronic obstructive pulmonary disease (AE-COPD) are leading causes of mortality in hospital intensive care units. We sought to determine whether dental plaque biofilms might harbor pathogenic bacteria that can eventually cause lung infections in patients with severe AE-COPD. Paired samples of subgingival plaque biofilm and tracheal aspirate were collected from 53 patients with severe AE-COPD. Total bacterial DNA was extracted from each sample individually for polymerase chain reaction amplification and/or generation of bacterial 16S rDNA sequences and cDNA libraries. We used a metagenomic approach, based on bacterial 16S rDNA sequences, to compare the distribution of species present in dental plaque and lung. Analysis of 1060 sequences (20 clones per patient) revealed a wide range of aerobic, anaerobic, pathogenic, opportunistic, novel and uncultivable bacterial species. Species indistinguishable between the paired subgingival plaque and tracheal aspirate samples (97-100% similarity in 16S rDNA sequence) were dental plaque pathogens (Aggregatibacter actinomycetemcomitans, Capnocytophaga sputigena, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola) and lung pathogens (Acinetobacter baumannii, Klebsiella pneumoniae, Pseudomonas aeruginosa and Streptococcus pneumoniae). Real-time polymerase chain reaction of 16S rDNA indicated lower levels of Pseudomonas aeruginosa and Porphyromonas gingivalis colonizing the dental plaques compared with the paired tracheal aspirate samples. These results support the hypothesis that dental bacteria may contribute to the pathology of severe AE-COPD. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Protective effect of topical Cordia verbenacea in a rat periodontitis model: immune-inflammatory, antibacterial and morphometric assays

PubMed Central

2012-01-01

Background This study evaluated the effects of C. verbenacea essential oil topically administered in a rat periodontitis model. Methods Periodontitis was induced on rats in one of the mandibular first molars assigned to receive a ligature. Animals were randomly divided into two groups: a) non-treatment group (NT) (n = 18): animals received 1mL of vehicle; b) C. verbenacea group (C.v.) (n = 18): animals received 5mg/Kg of essential oils isolated from C. verbenacea. The therapies were administered topically 3 times daily for 11 days. Then, the specimens were processed for morphometric analysis of bone loss. The ligatures were used for microbiological assessment of the presence of Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Porphyromonas gingivalis using PCR. The gingival tissue was collected to Elisa assay of interleukin (IL)-1α and IL-10 levels. Results Bone loss was inhibited by C. verbenacea when compared to the NT group (p < 0.05). A decrease in the levels of IL-1α and increase in the IL-10 amounts was observed in the C.v. group as compared to NT group (p < 0.05). A lower frequency of P. gingivalis was found in C.v. group (p < 0.05). Conclusion C. verbenacea essential oil topically administered diminished alveolar bone resorption, promoting a positive local imbalance in the pro/anti-inflammatory system and reducing the frequency of detection of P. gingivalis. PMID:23171319

Detection of periodontal bacteria in thrombi of patients with acute myocardial infarction by polymerase chain reaction.

PubMed

Ohki, Takahiro; Itabashi, Yuji; Kohno, Takashi; Yoshizawa, Akihiro; Nishikubo, Shuichi; Watanabe, Shinya; Yamane, Genyuki; Ishihara, Kazuyuki

2012-02-01

Numerous reports have demonstrated that periodontal bacteria are present in plaques from atherosclerotic arteries. Although periodontitis has recently been recognized as a risk factor for coronary artery disease, the direct relationship between periodontal bacteria and coronary artery disease has not yet been clarified. It has been suggested that these bacteria might contribute to inflammation and plaque instability. We assumed that if periodontal bacteria induce inflammation of plaque, the bacteria would be released into the bloodstream when vulnerable plaque ruptures. To determine whether periodontal bacteria are present in thrombi at the site of acute myocardial infarction, we tried to detect periodontal bacteria in thrombi of patients with acute myocardial infarction by polymerase chain reaction (PCR). We studied 81 consecutive adults with ST-segment elevation acute myocardial infarction who underwent primary percutaneous coronary intervention (PCI). All patients underwent removal of thrombus with aspiration catheters at the beginning of percutaneous coronary intervention, and a small sample of thrombus was obtained for PCR. The detection rates of periodontal bacteria by PCR were 19.7% for Aggregatibacter actinomycetemcomitans, 3.4% for Porphyromonas gingivalis, and 2.3% for Treponema denticola. Three species of periodontal bacteria were detected in the thrombi of patients with acute myocardial infarction. This raises the possibility that such bacteria are latently present in plaque and also suggests that these bacteria might have a role in plaque inflammation and instability. Copyright © 2012 Mosby, Inc. All rights reserved.

Structural Characterization of Core Region in Erwinia amylovora Lipopolysaccharide.

PubMed

Casillo, Angela; Ziaco, Marcello; Lindner, Buko; Merino, Susana; Mendoza-Barberá, Elena; Tomás, Juan M; Corsaro, Maria Michela

2017-03-04

Erwinia amylovora ( E. amylovora ) is the first bacterial plant pathogen described and demonstrated to cause fire blight, a devastating plant disease affecting a wide range of species including a wide variety of Rosaceae . In this study, we reported the lipopolysaccharide (LPS) core structure from E. amylovora strain CFBP1430, the first one for an E. amylovora highly pathogenic strain. The chemical characterization was performed on the mutants waaL (lacking only the O-antigen LPS with a complete LPS-core), wabH and wabG (outer-LPS core mutants). The LPSs were isolated from dry cells and analyzed by means of chemical and spectroscopic methods. In particular, they were subjected to a mild acid hydrolysis and/or a hydrazinolysis and investigated in detail by one and two dimensional Nuclear Magnetic Resonance (NMR) spectroscopy and ElectroSpray Ionization Fourier Transform-Ion Cyclotron Resonance (ESI FT-ICR) mass spectrometry.

Lipopolysaccharide administration in the dominant mouse destabilizes social hierarchy.

PubMed

Cohn, Daniel Wagner Hamada; Gabanyi, Ilana; Kinoshita, Denise; de Sá-Rocha, Luiz Carlos

2012-09-01

Sickness behavior is a set of behavioral changes that are part of an adaptive strategy to overcome infection. Mice that interact with conspecifics displaying sickness behavior also show relevant behavioral changes. In this work we sought to determine the role of sickness behavior display by a dominant mouse as a promoter of hierarchy instability. We treated the dominant mouse within a dyad with lipopolysaccharide (LPS) (400 μg/kg, i.p.) for three consecutive days and assessed social dominance behavior. Since elder animals display increased inflammatory responses and the behaviors toward conspecifics are influenced by kinship we also assessed whether kinship and age, might influence sickness related hierarchy instability. Our results show that administration of LPS in the dominant mouse promotes social instability within a dyad, and indicates that this instability could be influenced by kinship and age. Copyright © 2012 Elsevier B.V. All rights reserved.

Pleurotus eryngii Ameliorates Lipopolysaccharide-Induced Lung Inflammation in Mice.

PubMed

Kawai, Junya; Andoh, Tsugunobu; Ouchi, Kenji; Inatomi, Satoshi

2014-01-01

Pleurotus eryngii (P. eryngii) is consumed as a fresh cultivated mushroom worldwide and demonstrated to have multiple beneficial effects. We investigated the anti-inflammatory effect of P. eryngii in mice with acute lung injury (ALI). Intranasal instillation of lipopolysaccharide (LPS) (10  μ g/site/mouse) induced marked lung inflammation (increase in the number of inflammatory cells, protein leakage, and production of nitric oxide in bronchoalveolar lavage fluid) as well as histopathological damage in the lung, 6 h after treatment. Mice administered heat-treated P. eryngii (0.3-1 g/kg, p.o. (HTPE)) 1 h before LPS challenge showed decreased pulmonary inflammation and ameliorated histopathological damage. These results suggest that HTPE has anti-inflammatory effects against ALI. Thus, P. eryngii itself may also have anti-inflammatory effects and could be a beneficial food for the prevention of ALI induced by bacterial infection.

Pleurotus eryngii Ameliorates Lipopolysaccharide-Induced Lung Inflammation in Mice

PubMed Central

Andoh, Tsugunobu; Ouchi, Kenji; Inatomi, Satoshi

2014-01-01

Pleurotus eryngii (P. eryngii) is consumed as a fresh cultivated mushroom worldwide and demonstrated to have multiple beneficial effects. We investigated the anti-inflammatory effect of P. eryngii in mice with acute lung injury (ALI). Intranasal instillation of lipopolysaccharide (LPS) (10 μg/site/mouse) induced marked lung inflammation (increase in the number of inflammatory cells, protein leakage, and production of nitric oxide in bronchoalveolar lavage fluid) as well as histopathological damage in the lung, 6 h after treatment. Mice administered heat-treated P. eryngii (0.3–1 g/kg, p.o. (HTPE)) 1 h before LPS challenge showed decreased pulmonary inflammation and ameliorated histopathological damage. These results suggest that HTPE has anti-inflammatory effects against ALI. Thus, P. eryngii itself may also have anti-inflammatory effects and could be a beneficial food for the prevention of ALI induced by bacterial infection. PMID:24799939

Lipopolysaccharide Binding Protein Enables Intestinal Epithelial Restitution Despite Lipopolysaccharide Exposure

PubMed Central

Richter, Juli M.; Schanbacher, Brandon L.; Huang, Hong; Xue, Jianjing; Bauer, John A.; Giannone, Peter J.

2011-01-01

Intestinal epithelial restitution is the first part in the process of mucosal repair after injury in the intestine. Integrity of the intestinal mucosal barrier is important as a first line of defense against bacteria and endotoxin. Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in extremely low birth weight infants, but its mechanisms are not well defined. Abnormal bacterial colonization, immature barrier function, innate immunity activation and inflammation likely play a role. Lipopolysaccharide (LPS) binding protein (LBP) is secreted by enterocytes in response to inflammatory stimuli and has concentration-dependent effects. At basal concentrations, LBP stimulates the inflammatory response by presenting LPS to its receptor. However, at high concentrations, LBP is able to neutralize LPS and prevent an exaggerated inflammatory response. We sought to determine how LBP would affect wound healing in an in vitro model of intestinal cell restitution and protect against intestinal injury in a rodent model of NEC. Immature intestinal epithelial cells (IEC-6) were seeded in poly-l-lysine coated 8 chamber slides and grown to confluence. A 500μm wound was created using a cell scraper mounted on the microscope to achieve uniform wounding. Media was replaced with media containing LPS +/− LBP. Slide wells were imaged after 0, 8, and 24 hours and then fixed. Cellular restitution was evaluated via digital images captured on an inverted microscope and wound closure was determined by automated analysis. TLR4 was determined by rtPCR after RNA isolation from wounded cells 24 hours after treatment. LPS alone attenuated wound healing in immature intestinal epithelium. This attenuation is reversed by 24 hours with increasing concentrations of LBP so that wound healing is equivalent to control (p< 0.001). TLR4 was increased with LPS alone but levels returned to that of control after addition of LBP in the higher concentrations. LBP had no effect on the

Exogenous heat shock protein HSP70 reduces response of human neuroblastoma cells to lipopolysaccharide.

PubMed

Yurinskaya, M M; Funikov, S Y; Evgen'ev, M B; Vinokurov, M G

2016-07-01

The effect of exogenous heat shock protein HSP70 and lipopolysaccharide (LPS) on the production of reactive oxygen species (ROS), TNFα secretion, and mRNA expression by human neuroblastoma SK-N-SH cells. It was shown that exogenous HSP70 protects neuroblastoma cells from the action of LPS. The protection mechanism of HSP70 includes a reduction in the production of ROS and TNFα and a decrease in the expression of TLR4 and IL-1β mRNA in SK-N-SH cells induced by LPS.

Endotoxicosis induced by Coxiella burnetii lipopolysaccharide stimulates a ribosomal protein S6 kinase: some properties of the partially purified enzyme.

PubMed Central

Picking, W D; Hackstadt, T; Paretsky, D

1989-01-01

Guinea pig endotoxicosis induced by lipopolysaccharide from Coxiella burnetii Nine Mile phase I stimulates phosphorylation of liver ribosomal protein S6, with a 50% increase at 12 h postinoculation. The responsible protein kinase (S6PK) has been partially purified from liver; its activity is independent of cyclic AMP and of Ca2+ plus phosphatidyl serine or diacylglycerol. The preparation has an apparent optimum concentration of 20 mM Mg2+, while Ca2+ and Mn2+ are each inhibitory at 2 mM. The apparent Km for ATP is 30 microM with intact ribosomes. Because of the central role of phosphorylation in metabolic regulation and a purported role of phosphorylated S6 in protein synthesis, the lipopolysaccharide-induced stimulation of S6PK suggests a significant regulatory role of such enzymes in the pathobiochemistry of Q fever infection and endotoxicosis. Images PMID:2807543

Structural characterization of the lipid A region of Aeromonas salmonicida subsp. salmonicida lipopolysaccharide.

PubMed

Wang, Zhan; Li, Jianjun; Altman, Eleonora

2006-12-11

The lipid A components of Aeromonas salmonicida subsp. salmonicida from strains A449, 80204-1 and an in vivo rough isolate were isolated by mild acid hydrolysis of the lipopolysaccharide. Structural studies carried out by a combination of fatty acid, electrospray ionization-mass spectrometry and nuclear magnetic resonance analyses confirmed that the structure of lipid A was conserved among different isolates of A. salmonicida subsp. salmonicida. All analyzed strains contained three major lipid A molecules differing in acylation patterns corresponding to tetra-, penta- and hexaacylated lipid A species and comprising 4'-monophosphorylated beta-2-amino-2-deoxy-d-glucopyranose-(1-->6)-2-amino-2-deoxy-d-glucopyranose disaccharide, where the reducing end 2-amino-2-deoxy-d-glucose was present primarily in the alpha-pyranose form. Electrospray ionization-tandem mass spectrometry fragment pattern analysis, including investigation of the inner-ring fragmentation, allowed the localization of fatty acyl residues on the disaccharide backbone of lipid A. The tetraacylated lipid A structure containing 3-(dodecanoyloxy)tetradecanoic acid at N-2',3-hydroxytetradecanoic acid at N-2 and 3-hydroxytetradecanoic acid at O-3, respectively, was found. The pentaacyl lipid A molecule had a similar fatty acid distribution pattern and, additionally, carried 3-hydroxytetradecanoic acid at O-3'. In the hexaacylated lipid A structure, 3-hydroxytetradecanoic acid at O-3' was esterified with a secondary 9-hexadecenoic acid. Interestingly, lipid A of the in vivo rough isolate contained predominantly tetra- and pentaacylated lipid A species suggesting that the presence of the hexaacyl lipid A was associated with the smooth-form lipopolysaccharide.

Anti-Inflammatory Effects of Hyptis albida Chloroform Extract on Lipopolysaccharide-Stimulated Peritoneal Macrophages

PubMed Central

Sánchez Miranda, Elizabeth; Pérez Ramos, Julia; Fresán Orozco, Cristina; Zavala Sánchez, Miguel Angel; Pérez Gutiérrez, Salud

2013-01-01

We examined the effects of a chloroform extract of Hyptis albida (CHA) on inflammatory responses in mouse lipopolysaccharide (LPS) induced peritoneal macrophages. Our findings indicate that CHA inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin-6 (IL-6). During the process, levels of cyclooxygenase-2 (COX-2), nitric oxide synthase (iNOS), and nitric oxide (NO) increased in the mouse peritoneal macrophages; however, the extract suppressed them significantly. These results provide novel insights into the anti-inflammatory actions of CHA and support its potential use in the treatment of inflammatory diseases. PMID:23970974

Lipopolysaccharide induces amyloid formation of antimicrobial peptide HAL-2.

PubMed

Wang, Jiarong; Li, Yan; Wang, Xiaoming; Chen, Wei; Sun, Hongbin; Wang, Junfeng

2014-11-01

Lipopolysaccharide (LPS), the important component of the outer membrane of Gram-negative bacteria, contributes to the integrity of the outer membrane and protects the cell against bactericidal agents, including antimicrobial peptides. However, the mechanisms of interaction between antimicrobial peptides and LPS are not clearly understood. Halictines-2 (HAL-2), one of the novel antimicrobial peptides, was isolated from the venom of the eusocial bee Halictus sexcinctus. HAL-2 has exhibited potent antimicrobial activity against Gram-positive and Gram-negative bacteria and even against cancer cells. Here, we studied the interactions between HAL-2 and LPS to elucidate the antibacterial mechanism of HAL-2 in vitro. Our results show that HAL-2 adopts a significant degree of β-strand structure in the presence of LPS. LPS is capable of inducing HAL-2 amyloid formation, which may play a vital role in its antimicrobial activity. Copyright © 2014 Elsevier B.V. All rights reserved.

Naringin protects against lipopolysaccharide-induced cardiac injury in mice.

PubMed

Xianchu, Liu; Lan, Professor Zheng; Qiufang, Li; Yi, Liu; Xiangcheng, Ruan; Wenqi, Hou; Yang, Ding

2016-12-01

Previous research has demonstrated that lipopolysaccharide (LPS) can induce sepsis and lead to myocardial dysfunction. Naringin has various biological activities in LPS-induced sepsis. In this study, our aim was to investigate the effects of Naringin on LPS-induced cardiac injury and clarify its potential mechanism. We found that in vivo treatment with Naringin significantly ameliorated body weight loss, and attenuated cardiac histopathological changes after LPS challenge. Furthermore, Naringin inhibited LPS-induced increase of TNF-α, IL-1β and IL-6 activities to alleviate inflammatory response in heart. Moreover, Naringin supplement dramatically increased SOD levels, and prevented MDA levels to ameliorate oxidative stress compared with the LPS group in heart. Lastly, treatment with Naringin also significantly decreased the ratio of BAX to BCL-2 to resist apoptosis in heart. It is concluded that Naringin may be a promising therapeutic agent on LPS-induced cardiac injury by anti-inflammatory, anti-oxidant and anti-apoptotic effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Lipopolysaccharide Structure and Biosynthesis in Helicobacter pylori.

PubMed

Li, Hong; Liao, Tingting; Debowski, Aleksandra W; Tang, Hong; Nilsson, Hans-Olof; Stubbs, Keith A; Marshall, Barry J; Benghezal, Mohammed

2016-12-01

This review covers the current knowledge and gaps in Helicobacter pylori lipopolysaccharide (LPS) structure and biosynthesis. H. pylori is a Gram-negative bacterium which colonizes the luminal surface of the human gastric epithelium. Both a constitutive alteration of the lipid A preventing TLR4 elicitation and host mimicry of the Lewis antigen decorated O-antigen of H. pylori LPS promote immune escape and chronic infection. To date, the complete structure of H. pylori LPS is not available, and the proposed model is a linear arrangement composed of the inner core defined as the hexa-saccharide (Kdo-LD-Hep-LD-Hep-DD-Hep-Gal-Glc), the outer core composed of a conserved trisaccharide (-GlcNAc-Fuc-DD-Hep-) linked to the third heptose of the inner core, the glucan, the heptan and a variable O-antigen, generally consisting of a poly-LacNAc decorated with Lewis antigens. Although the glycosyltransferases (GTs) responsible for the biosynthesis of the H. pylori O-antigen chains have been identified and characterized, there are many gaps in regard to the biosynthesis of the core LPS. These limitations warrant additional mutagenesis and structural studies to obtain the complete LPS structure and corresponding biosynthetic pathway of this important gastric bacterium. © 2016 John Wiley & Sons Ltd.

The Myriad Properties of Pasteurella multocida Lipopolysaccharide

PubMed Central

Harper, Marina; Boyce, John Dallas

2017-01-01

Pasteurella multocida is a heterogeneous species that is a primary pathogen of many different vertebrates. This Gram-negative bacterium can cause a range of diseases, including fowl cholera in birds, haemorrhagic septicaemia in ungulates, atrophic rhinitis in swine, and lower respiratory tract infections in cattle and pigs. One of the primary virulence factors of P. multocida is lipopolysaccharide (LPS). Recent work has shown that this crucial surface molecule shows significant structural variability across different P. multocida strains, with many producing LPS structures that are highly similar to the carbohydrate component of host glycoproteins. It is likely that this LPS mimicry of host molecules plays a major role in the survival of P. multocida in certain host niches. P. multocida LPS also plays a significant role in resisting the action of chicken cathelicidins, and is a strong stimulator of host immune responses. The inflammatory response to the endotoxic lipid A component is a major contributor to the pathogenesis of certain infections. Recent work has shown that vaccines containing killed bacteria give protection only against other strains with identical, or nearly identical, surface LPS structures. Conversely, live attenuated vaccines give protection that is broadly protective, and their efficacy is independent of LPS structure. PMID:28825691

Protective Effects of Edaravone in Adult Rats with Surgery and Lipopolysaccharide Administration-Induced Cognitive Function Impairment.

PubMed

Wang, Peiqi; Cao, Jiangbei; Liu, Na; Ma, Li; Zhou, Xueyue; Zhang, Hong; Wang, Yongan

2016-01-01

Postoperative cognitive dysfunction (POCD) is a clinical syndrome characterized by cognitive declines in patients after surgery. Previous studies have suggested that surgery contributed to such impairment. It has been proven that neuroinflammation may exacerbate surgery-induced cognitive impairment in aged rats. The free radical scavenger edaravone has high blood brain barrier permeability, and was demonstrated to effectively remove free radicals from the brain and alleviate the development of POCD in patients undergoing carotid endarterectomy, suggesting its potential role in preventing POCD. For this reason, this study was designed to determine whether edaravone is protective against POCD through its inhibitory effects on inflammatory cytokines and oxidative stress. First, Sprague Dawley adult male rats were administered 3 mg/kg edaravone intraperitoneally after undergoing a unilateral nephrectomy combined with lipopolysaccharide injection. Second, behavioral parameters related to cognitive function were recorded by fear conditioning and Morris Water Maze tests. Last, superoxide dismutase activities and malondialdehyde levels were measured in the hippocampi and prefrontal cortex on postoperative days 3 and 7, and microglial (Iba1) activation, p-Akt and p-mTOR protein expression, and synaptic function (synapsin 1) were also examined 3 and 7 days after surgery. Rats that underwent surgery plus lipopolysaccharide administration showed significant impairments in spatial and working memory, accompanied by significant reductions in hippocampal-dependent and independent fear responses. All impairments were attenuated by treatment with edaravone. Moreover, an abnormal decrease in superoxide dismutase activation, abnormal increase in malondialdehyde levels, significant increase in microglial reactivity, downregulation of p-Akt and p-mTOR protein expression, and a statistically significant decrease in synapsin-1 were observed in the hippocampi and prefrontal cortices of

Protective Effects of Edaravone in Adult Rats with Surgery and Lipopolysaccharide Administration-Induced Cognitive Function Impairment

PubMed Central

Liu, Na; Ma, Li; Zhou, Xueyue; Zhang, Hong; Wang, Yongan

2016-01-01

Postoperative cognitive dysfunction (POCD) is a clinical syndrome characterized by cognitive declines in patients after surgery. Previous studies have suggested that surgery contributed to such impairment. It has been proven that neuroinflammation may exacerbate surgery-induced cognitive impairment in aged rats. The free radical scavenger edaravone has high blood brain barrier permeability, and was demonstrated to effectively remove free radicals from the brain and alleviate the development of POCD in patients undergoing carotid endarterectomy, suggesting its potential role in preventing POCD. For this reason, this study was designed to determine whether edaravone is protective against POCD through its inhibitory effects on inflammatory cytokines and oxidative stress. First, Sprague Dawley adult male rats were administered 3 mg/kg edaravone intraperitoneally after undergoing a unilateral nephrectomy combined with lipopolysaccharide injection. Second, behavioral parameters related to cognitive function were recorded by fear conditioning and Morris Water Maze tests. Last, superoxide dismutase activities and malondialdehyde levels were measured in the hippocampi and prefrontal cortex on postoperative days 3 and 7, and microglial (Iba1) activation, p-Akt and p-mTOR protein expression, and synaptic function (synapsin 1) were also examined 3 and 7 days after surgery. Rats that underwent surgery plus lipopolysaccharide administration showed significant impairments in spatial and working memory, accompanied by significant reductions in hippocampal-dependent and independent fear responses. All impairments were attenuated by treatment with edaravone. Moreover, an abnormal decrease in superoxide dismutase activation, abnormal increase in malondialdehyde levels, significant increase in microglial reactivity, downregulation of p-Akt and p-mTOR protein expression, and a statistically significant decrease in synapsin-1 were observed in the hippocampi and prefrontal cortices of

Proteins required for lipopolysaccharide assembly in Escherichia coli form a trans-envelope complex†

PubMed Central

Chng, Shu-Sin; Gronenberg, Luisa S.; Kahne, Daniel

2010-01-01

The viability of Gram-negative organisms is dependent on the proper placement of lipopolysaccharide (LPS) in the outer leaflet of its outer membrane. LPS is synthesized inside the cell and transported to the surface by seven essential Lpt proteins. How these proteins cooperate to transport LPS is unknown. We show that these Lpt proteins can be found in a membrane fraction that contains inner and outer membranes, and that they co-purify. This constitutes the first evidence that the Lpt proteins form a trans-envelope complex. We suggest that this protein bridge provides a route for LPS transport across the cell envelope. PMID:20446753

Dopamine-dependent neurotoxicity of lipopolysaccharide in substantia nigra.

PubMed

De Pablos, Rocío M; Herrera, Antonio J; Villarán, Ruth F; Cano, Josefina; Machado, Alberto

2005-03-01

Intranigral injection of lipopolysaccharide (LPS), a potent inductor of inflammation, induces degeneration of dopaminergic neurons, along with an inflammatory process that features activation of microglial cells and loss of astrocytes. To test the involvement of dopamine (DA) in this degeneration induced by LPS, we treated albino Wistar rats with different concentrations of alpha-methyl-p-tyrosine (alpha-MPT), an inhibitor of tyrosine hydroxylase (TH) activity. Results showed that alpha-MPT prevented LPS-induced loss of TH immunostaining and expression of mRNA for TH and DA transporter; it also prevented substantial activation of microglial cells. Loss of the astroglial population, a marker of damage in our model, was also prevented. This protective effect resulted from inhibition of TH and the consequent decrease in DA concentration, because treatment with L-DOPA/benserazide, which bypasses TH inhibition induced by alpha-MPT, reversed the protective effect produced by this drug. These results point out the important contribution of DA to the vulnerability and degeneration of dopaminergic neurons of the substantia nigra. Knowledge about the involvement of DA in this process may lead to the possibility of new protection strategies against this important degenerative process.

Long term effects of lipopolysaccharide on satellite glial cells in mouse dorsal root ganglia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blum, E.; Procacci, P.; Conte, V.

Lipopolysaccharide (LPS) has been used extensively to study neuroinflammation, but usually its effects were examined acutely (24 h<). We have shown previously that a single intraperitoneal LPS injection activated satellite glial cells (SGCs) in mouse dorsal root ganglia (DRG) and altered several functional parameters in these cells for at least one week. Here we asked whether the LPS effects would persist for 1 month. We injected mice with a single LPS dose and tested pain behavior, assessed SGCs activation in DRG using glial fibrillary acidic protein (GFAP) immunostaining, and injected a fluorescent dye intracellularly to study intercellular coupling. Electron microscopymore » was used to quantitate changes in gap junctions. We found that at 30 days post-LPS the threshold to mechanical stimulation was lower than in controls. GFAP expression, as well as the magnitude of dye coupling among SGCs were greater than in controls. Electron microscopy analysis supported these results, showing a greater number of gap junctions and an abnormal growth of SGC processes. These changes were significant, but less prominent than at 7 days post-LPS. We conclude that a single LPS injection exerts long-term behavioral and cellular changes. The results are consistent with the idea that SGC activation contributes to hyperalgesia. - Highlights: • A single lipopolysaccharides injection activated glia in mouse dorsal root ganglia for 30 days. • This was accompanied by increased communications by gap junctions among glia and by hyperalgesia. • Glial activation and coupling may contribute to chronic pain.« less

Bowman-Birk inhibitor and genistein among soy compounds that synergistically inhibit nitric oxide and prostaglandin E2 pathways in lipopolysaccharide-induced macrophages

USDA-ARS?s Scientific Manuscript database

Inflammation has an important role in the development of chronic diseases. In this study, we evaluated the anti-inflammatory properties of eight soybean bioactive compounds using lipopolysaccharide-induced RAW 264.7 macrophages. Genistein, daidzein, mix isoflavone glucosides, saponin A group glyco...

Lipopolysaccharide-induced early response genes in bovine peripheral blood mononuclear cells implicate GLG1/E-selectin as a key ligand–receptor interaction

USDA-ARS?s Scientific Manuscript database

This study uses a systems biology approach, integrating global gene expression information and knowledge of the regulatory events in cells to identify transcription networks controlling peripheral blood mononuclear cells’ (PBMCs) immune response to lipopolysaccharide (LPS) and to identify the molecu...

Relationship of the Structure of Bacterial Lipopolysaccharides to Its Function in Mitogenesis and Adjuvanticity

PubMed Central

Chiller, Jacques M.; Skidmore, Barry J.; Morrison, David C.; Weigle, William O.

1973-01-01

The ability of bacterial lipopolysaccharides to induce lymphocyte mitogenesis and to act as an adjuvant of antibody formation was attributable to the lipid-A region of the molecule. Measured by induction of DNA synthesis, lipid A was mitogenic for bone marrow-derived lymphocytes obtained from spleens of congenitally athymic mice but not for thymocytes obtained from thymuses of normal mice. Adjuvanticity was demonstrated by the ability of lipid A to convert a tolerogenic regimen of antigen into one eliciting an immune response and by its ability to markedly enhance the antibody response to a weak antigen. PMID:4579014

Evaluation of the innate immune response of Angus heifers with genetic marker variation for intramuscular fat deposition following a lipopolysaccharide challenge

USDA-ARS?s Scientific Manuscript database

This study evaluated the effect of genetic selection for markers related to marbling deposition in Angus heifers on the immune response following a lipopolysaccharide (LPS) challenge. Fall-born heifers (n = 19; ~7 months of age, 274 +/- 24 kg) with genetic variation for marbling were utilized inclu...

Modulation of the acute phase response following a lipopolysaccharide challenge in pigs supplemented with an all-natural Saccharomyces cerevisiae fermentation product

USDA-ARS?s Scientific Manuscript database

This study was designed to determine if feeding a Saccharomyces cerevisiae fermentation product to weaned pigs would reduce the stress and acute phase responses (APR) following an acute lipopolysaccharide (LPS) challenge. Pigs (n = 20; 6.4 +/- 0.2 kg body weight) were obtained and transported to an ...

Excretory, secretory, and tissue residues after label and extra-label administration of flunixin meglumine to saline or lipopolysaccharide-exposed dairy cows

USDA-ARS?s Scientific Manuscript database

Twenty lactating dairy cattle were intravenously infused with either lipopolysaccharide (n = 10) or sterile saline (n = 10). Five cattle in each group received 3 doses of flunixin meglumine administered by either IV infusion or IM injection at 24 h intervals. Milk, urine, and tissues were collected....

Effects of Dextrose and Lipopolysaccharide on the Corrosion Behavior of a Ti-6Al-4V Alloy with a Smooth Surface or Treated with Double-Acid-Etching

PubMed Central

Faverani, Leonardo P.; Assunção, Wirley G.; de Carvalho, Paulo Sérgio P.; Yuan, Judy Chia-Chun; Sukotjo, Cortino; Mathew, Mathew T.; Barao, Valentim A.

2014-01-01

Diabetes and infections are associated with a high risk of implant failure. However, the effects of such conditions on the electrochemical stability of titanium materials remain unclear. This study evaluated the corrosion behavior of a Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching, in simulated body fluid with different concentrations of dextrose and lipopolysaccharide. For the electrochemical assay, the open-circuit-potential, electrochemical impedance spectroscopy, and potentiodynamic test were used. The disc surfaces were characterized by scanning electron microscopy and atomic force microscopy. Their surface roughness and Vickers microhardness were also tested. The quantitative data were analyzed by Pearson's correlation and independent t-tests (α = 0.05). In the corrosion parameters, there was a strong lipopolysaccharide correlation with the Ipass (passivation current density), Cdl (double-layer capacitance), and Rp (polarization resistance) values (p<0.05) for the Ti-6Al-4V alloy with surface treatment by double-acid-etching. The combination of dextrose and lipopolysaccharide was correlated with the Icorr (corrosion current density) and Ipass (p<0.05). The acid-treated groups showed a significant increase in Cdl values and reduced Rp values (p<0.05, t-test). According to the topography, there was an increase in surface roughness (R2 = 0.726, p<0.0001 for the smooth surface; R2 = 0.405, p = 0.036 for the double-acid-etching-treated surface). The microhardness of the smooth Ti-6Al-4V alloy decreased (p<0.05) and that of the treated Ti-6Al-4V alloy increased (p<0.0001). Atomic force microscopy showed changes in the microstructure of the Ti-6Al-4V alloy by increasing the surface thickness mainly in the group associated with dextrose and lipopolysaccharide. The combination of dextrose and lipopolysaccharide affected the corrosion behavior of the Ti-6Al-4V alloy surface treated with double-acid-etching. However, no

Effects of dextrose and lipopolysaccharide on the corrosion behavior of a Ti-6Al-4V alloy with a smooth surface or treated with double-acid-etching.

PubMed

Faverani, Leonardo P; Assunção, Wirley G; de Carvalho, Paulo Sérgio P; Yuan, Judy Chia-Chun; Sukotjo, Cortino; Mathew, Mathew T; Barao, Valentim A

2014-01-01

Diabetes and infections are associated with a high risk of implant failure. However, the effects of such conditions on the electrochemical stability of titanium materials remain unclear. This study evaluated the corrosion behavior of a Ti-6Al-4V alloy, with a smooth surface or conditioned by double-acid-etching, in simulated body fluid with different concentrations of dextrose and lipopolysaccharide. For the electrochemical assay, the open-circuit-potential, electrochemical impedance spectroscopy, and potentiodynamic test were used. The disc surfaces were characterized by scanning electron microscopy and atomic force microscopy. Their surface roughness and Vickers microhardness were also tested. The quantitative data were analyzed by Pearson's correlation and independent t-tests (α = 0.05). In the corrosion parameters, there was a strong lipopolysaccharide correlation with the Ipass (passivation current density), Cdl (double-layer capacitance), and Rp (polarization resistance) values (p<0.05) for the Ti-6Al-4V alloy with surface treatment by double-acid-etching. The combination of dextrose and lipopolysaccharide was correlated with the Icorr (corrosion current density) and Ipass (p<0.05). The acid-treated groups showed a significant increase in Cdl values and reduced Rp values (p<0.05, t-test). According to the topography, there was an increase in surface roughness (R2 = 0.726, p<0.0001 for the smooth surface; R2 = 0.405, p = 0.036 for the double-acid-etching-treated surface). The microhardness of the smooth Ti-6Al-4V alloy decreased (p<0.05) and that of the treated Ti-6Al-4V alloy increased (p<0.0001). Atomic force microscopy showed changes in the microstructure of the Ti-6Al-4V alloy by increasing the surface thickness mainly in the group associated with dextrose and lipopolysaccharide. The combination of dextrose and lipopolysaccharide affected the corrosion behavior of the Ti-6Al-4V alloy surface treated with double-acid-etching. However, no

Structural correlation between lipophilicity and lipopolysaccharide-sequestering activity in spermine-sulfonamide analogs.

PubMed

Burns, Mark R; Jenkins, Scott A; Vermeulen, Nicolas M; Balakrishna, Rajalakshmi; Nguyen, Thuan B; Kimbrell, Matthew R; David, Sunil A

2006-12-15

Lipopolysaccharides (LPS), otherwise termed 'endotoxins', are outer-membrane constituents of Gram-negative bacteria, and play a key role in the pathogenesis of 'Septic Shock', a major cause of mortality in the critically ill patient. We had previously defined the pharmacophore necessary for small molecules to specifically bind and neutralize this complex carbohydrate. A series of aryl and aliphatic spermine-sulfonamide analogs were synthesized and tested in a series of binding and cell-based assays in order to probe the effect of lipophilicity on sequestration ability. A strong correlation was indeed found, supporting the hypothesis that endotoxin-neutralizing ability involves a lipophilic or membrane attachment event. The research discussed herein may be useful for the design of additional carbohydrate recognizing molecules and endotoxin-neutralizing drugs.

Calcium hydroxide suppresses Porphyromonas endodontalis lipopolysaccharide-induced bone destruction.

PubMed

Guo, J; Yang, D; Okamura, H; Teramachi, J; Ochiai, K; Qiu, L; Haneji, T

2014-05-01

Porphyromonas endodontalis and its main virulence factor, lipopolysaccharide (LPS), are associated with the development of periapical diseases and alveolar bone loss. Calcium hydroxide is commonly used for endodontic therapy. However, the effects of calcium hydroxide on the virulence of P. endodontalis LPS and the mechanism of P. endodontalis LPS-induced bone destruction are not clear. Calcium hydroxide rescued the P. endodontalis LPS-suppressed viability of MC3T3-E1 cells and activity of nuclear factor-κB (NF-κB) in these cells, resulting in the reduced expression of interleukin-6 and tumor necrosis factor-α. In addition, calcium hydroxide inhibited P. endodontalis LPS-induced osteoclastogenesis by decreasing the activities of NF-κB, p38, and ERK1/2 and the expression of nuclear factor of activated T-cell cytoplasmic 1 in RAW264.7 cells. Calcium hydroxide also rescued the P. endodontalis LPS-induced osteoclastogenesis and bone destruction in mouse calvaria. Taken together, our present results indicate that calcium hydroxide suppressed bone destruction by attenuating the virulence of P. endodontalis LPS on bone cells.

Actinobacillus actinomycetemcomitans Y4 capsular polysaccharide induces IL-1β mRNA expression through the JNK pathway in differentiated THP-1 cells

PubMed Central

Iwata, T; Mitani, A; Ishihara, Y; Tanaka, S; Yamamoto, G; Kikuchi, T; Naganawa, T; Matsumura, Y; Suga, T; Koide, M; Sobue, T; Suzuki, T; Noguchi, T

2005-01-01

Capsular polysaccharide from Actinobacillus actinomycetemcomitans Y4 (Y4 CP) induces bone resorption in a mouse organ culture system and osteoclast formation in mouse bone marrow cultures, as reported in previous studies. We also found that Y4 CP inhibits the release of interleukin (IL)-6 and IL-8 from human gingival fibroblast (HGF). Thus Y4 CP induces various responses in localized tissue and leads to the secretion of several cytokines. However, the effects of Y4 CP on human monocytes/macrophages are still unclear. In this study, THP-1 cells, which are a human monocytic cell line, were stimulated with Y4 CP, and we measured gene expression in inflammatory cytokine and signal transduction pathways. IL-1β and tumour necrosis factor (TNF)-α mRNA were induced from Y4 CP-treated THP-1 cells. IL-1β mRNA expression was increased according to the dose of Y4 CP, and in a time-dependent manner. IL-1β mRNA expression induced by Y4 CP (100 µg/ml) was approximately 7- to 10-fold greater than that in the control by real-time PCR analysis. Furthermore, neither PD98059, a specific inhibitor of extracellular signal-regulated kinase nor SB203580, a specific inhibitor of p38 kinase prevented the IL-1β expression induced by Y4 CP. However, JNK Inhibitor II, a specific inhibitor of c-Jun N-terminal kinase (JNK) prevented the IL-1β mRNA expression induced by Y4 CP in a concentration-dependent manner. These results indicate that Y4 CP-mediated JNK pathways play an important role in the regulation of IL-1β mRNA. Therefore, Y4 CP-transduced signals for IL-1β induction in the antibacterial action of macrophages may provide a therapeutic strategy for periodontitis. PMID:15996190

Modulation of the acute phase response following a lipopolysaccharide challenge in pigs supplemented with an all-natural saccharomyces cerevisiae fermentation product

USDA-ARS?s Scientific Manuscript database

This study was designed to determine if feeding a Saccharamyces cerevisiae fermentation product to weaned pigs would reduce the stress and acute phase responses (APR) following an acute lipopolysaccharide (LPS) challenge. Pigs (n = 20; 6.4 ± 0.2 kg BW) were obtained and transported to an environment...

Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li Song; Zhang Junjie

2009-01-09

Autotaxin (ATX) is a secreted enzyme with lysophospholipase D (lysoPLD) activity, which converts lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), a bioactive phospholipid involved in numerous biological activities, including cell proliferation, differentiation, and migration. In the present study, we found that bacterial lipopolysaccharide (LPS), a well-known initiator of the inflammatory response, induced ATX expression in monocytic THP-1 cells. The activation of PKR, JNK, and p38 MAPK was required for the ATX induction. The LPS-induced ATX in THP-1 cells was characterized as the {beta} isoform. In the presence of LPC, ATX could promote the migrations of THP-1 and Jurkat cells, which wasmore » inhibited by pertussis toxin (PTX), an inhibitor of Gi-mediated LPA receptor signaling. In summary, LPS induces ATX expression in THP-1 cells via a PKR, JNK and p38 MAPK-mediated mechanism, and the ATX induction is likely to enhance immune cell migration in proinflammatory response by regulating LPA levels in the microenvironment.« less

Modulation of lipopolysaccharide-induced chorioamnionitis by Ureaplasma parvum in sheep

PubMed Central

SNYDER, Candice C.; WOLFE, Katherine B.; GISSLEN, Tate; KNOX, Christine L.; KEMP, Matthew W.; KRAMER, Boris W.; NEWNHAM, John P.; JOBE, Alan H.; KALLAPUR, Suhas G.

2013-01-01

Objective Ureaplasma colonization in the setting of polymicrobial flora is common in women with chorioamnionitis, and is a risk factor for preterm delivery and neonatal morbidity. We hypothesized that ureaplasma colonization of amniotic fluid will modulate chorioamnionitis induced by E. coli lipopolysaccharide (LPS). Methods Sheep received intra-amniotic (IA) injections of media (control) or live ureaplasma either 7 or 70d before delivery. Another group received IA LPS 2d before delivery. To test for interactions, U. parvum exposed animals were challenged with IA LPS, and delivered 2d later. All animals were delivered preterm at 125±1 day gestation. Results Both IA ureaplasmas and LPS induced leukocyte infiltration of chorioamnion. LPS greatly increased the expression of pro-inflammatory cytokines and myeloperoxidase in leukocytes, while ureaplasmas alone caused modest responses. Interestingly, 7d but not 70d ureaplasma exposure significantly downregulated LPS induced pro-inflammatory cytokines and myeloperoxidase expression in the chorioamnion. Conclusion Acute U. parvum exposure (7d) can suppress LPS induced chorioamnionitis. PMID:23410690

Attenuation of lipopolysaccharide (LPS)-induced cytotoxicity by tocopherols and tocotrienols.

PubMed

Nishio, Keiko; Horie, Masanori; Akazawa, Yoko; Shichiri, Mototada; Iwahashi, Hitoshi; Hagihara, Yoshihisa; Yoshida, Yasukazu; Niki, Etsuo

2013-01-01

Lipopolysaccharide (LPS) induces host inflammatory responses and tissue injury and has been implicated in the pathogenesis of various age-related diseases such as acute respiratory distress syndrome, vascular diseases, and periodontal disease. Antioxidants, particularly vitamin E, have been shown to suppress oxidative stress induced by LPS, but the previous studies with different vitamin E isoforms gave inconsistent results. In the present study, the protective effects of α- and γ-tocopherols and α- and γ-tocotrienols on the oxidative stress induced by LPS against human lung carcinoma A549 cells were studied. They suppressed intracellular reactive oxygen formation, lipid peroxidation, induction of inflammatory mediator cytokines, and cell death. Tocopherols were incorporated into cultured cells much slower than tocotrienols but could suppress LPS-induced oxidative stress at much lower intracellular concentration than tocotrienols. Considering the bioavailability, it was concluded that α-tocopherol may exhibit the highest protective capacity among the vitamin E isoforms against LPS-induced oxidative stress.

Lipopolysaccharide O-antigen delays plant innate immune recognition of Xylella fastidiosa.

PubMed

Rapicavoli, Jeannette N; Blanco-Ulate, Barbara; Muszyński, Artur; Figueroa-Balderas, Rosa; Morales-Cruz, Abraham; Azadi, Parastoo; Dobruchowska, Justyna M; Castro, Claudia; Cantu, Dario; Roper, M Caroline

2018-01-26

Lipopolysaccharides (LPS) are among the known pathogen-associated molecular patterns (PAMPs). LPSs are potent elicitors of PAMP-triggered immunity (PTI), and bacteria have evolved intricate mechanisms to dampen PTI. Here we demonstrate that Xylella fastidiosa (Xf), a hemibiotrophic plant pathogenic bacterium, possesses a long chain O-antigen that enables it to delay initial plant recognition, thereby allowing it to effectively skirt initial elicitation of innate immunity and establish itself in the host. Lack of the O-antigen modifies plant perception of Xf and enables elicitation of hallmarks of PTI, such as ROS production specifically in the plant xylem tissue compartment, a tissue not traditionally considered a spatial location of PTI. To explore translational applications of our findings, we demonstrate that pre-treatment of plants with Xf LPS primes grapevine defenses to confer tolerance to Xf challenge.

In vitro antioxidant capacities of eight different kinds of apples and their effects on lipopolysaccharide-induced oxidative damage in mice.

PubMed

Guo, Shuang; Wang, Yuehua; Chou, Shurui; Cui, Huijun; Li, Dongnan; Li, Bin

2018-01-01

In the present study, the DPPH and ABTS+ radical scavenging activity of eight types of apples decreased (P < 0.05) during the 70-day storage at 4°C. The Fushi (F2) apples from Xin Jiang showed the highest radical scavenging activity. For in vivo study, 40 male Kunming mice (body weight 20-25 g) were selected and randomly assigned to four groups (10 mice per group). The F2 groups (F2S, F2 + sterile saline and F2L, F2 + lipopolysaccharide) were administered with 0.3 mL F2 filtrate via gastric intubation daily for 28 days. The control groups (CS, CON + sterile saline and CL, CON + lipopolysaccharide) were treated with sterile saline at the same volume. At day 29, mice of F2L and CL groups were injected with 100 μg/kg body weight of lipopolysaccharide (LPS) intraperitoneally, while those of F2S and CS groups were injected equal volume of sterile saline. In comparison to the CS group, the CL group showed a decrease (P < 0.05) in serum, liver, and hepatic mitochondrial antioxidant capacity, reduction (P < 0.05) in the expression of hepatic antioxidant-related genes, and an increase (P < 0.05) in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), malondialdehyde (MDA), protein carbonyl (PC), and reactive oxygen species (ROS). In comparison to the CL group, the F2L group showed lower (P < 0.05) levels of serum ALT, AST, and ROS, higher (P < 0.05) level of serum, liver, and hepatic mitochondrial antioxidant capacity, increased mitochondrial membrane potential (MMP), and enhanced (P < 0.05) expression of hepatic antioxidant-related genes. These results suggest that F2 may exert protective effect against LPS-induced oxidative damage by improving the antioxidant capacity.

Multiple mechanisms involved in diabetes protection by lipopolysaccharide in non-obese diabetic mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jun; Department of Pharmacology, College of Medicine, Wuhan University of Science and Technology, Wuhan; Cao, Hui

Toll-like receptor 4 (TLR4) activation has been proposed to be important for islet cell inflammation and eventually β cell loss in the course of type 1 diabetes (T1D) development. However, according to the “hygiene hypothesis”, bacterial endotoxin lipopolysaccharide (LPS), an agonist on TLR4, inhibits T1D progression. Here we investigated possible mechanisms for the protective effect of LPS on T1D development in non-obese diabetic (NOD) mice. We found that LPS administration to NOD mice during the prediabetic state neither prevented nor reversed insulitis, but delayed the onset and decreased the incidence of diabetes, and that a multiple-injection protocol is more effectivemore » than a single LPS intervention. Further, LPS administration suppressed spleen T lymphocyte proliferation, increased the generation of CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T cells (Tregs), reduced the synthesis of strong Th1 proinflammatory cytokines, and downregulated TLR4 and its downstream MyD88-dependent signaling pathway. Most importantly, multiple injections of LPS induced a potential tolerogenic dendritic cell (DC) subset with low TLR4 expression without influencing the DC phenotype. Explanting DCs from repeated LPS-treated NOD mice into NOD/SCID diabetic mice conferred sustained protective effects against the progression of diabetes in the recipients. Overall, these results suggest that multiple mechanisms are involved in the protective effects of LPS against the development of diabetes in NOD diabetic mice. These include Treg induction, down-regulation of TLR4 and its downstream MyD88-dependent signaling pathway, and the emergence of a potential tolerogenic DC subset. - Highlights: • Administration of lipopolysaccharide (LPS) prevented type 1 diabetes in NOD mice. • Downregulating TLR4 level and MyD88-dependent pathway contributed to protection of LPS. • LPS administration also hampered DC maturation and promoted Treg differentiation.« less

Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up

PubMed Central

Morales, Alicia; Gandolfo, Alessandro; Bravo, Joel; Carvajal, Paola; Silva, Nora; Godoy, Claudia; Garcia-Sesnich, Jocelyn; Hoare, Anilei; Diaz, Patricia; Gamonal, Jorge

2018-01-01

ABSTRACT Objective The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Material and Methods Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. Results All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups. Conclusions The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group. PMID:29364340

Evaluating clinical periodontal measures as surrogates for bacterial exposure: The Oral Infections and Vascular Disease Epidemiology Study (INVEST)

PubMed Central

2010-01-01

Background Epidemiologic studies of periodontal infection as a risk factor for cardiovascular disease often use clinical periodontal measures as a surrogate for the underlying bacterial exposure of interest. There are currently no methodological studies evaluating which clinical periodontal measures best reflect the levels of subgingival bacterial colonization in population-based settings. We investigated the characteristics of clinical periodontal definitions that were most representative of exposure to bacterial species that are believed to be either markers, or themselves etiologic, of periodontal disease. Methods 706 men and women aged ≥ 55 years, residing in northern Manhattan were enrolled. Using DNA-DNA checkerboard hybridization in subgingival biofilms, standardized values for Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia were averaged within mouth and summed to define "bacterial burden". Correlations of bacterial burden with clinical periodontal constructs defined by the severity and extent of attachment loss (AL), pocket depth (PD) and bleeding on probing (BOP) were assessed. Results Clinical periodontal constructs demonstrating the highest correlations with bacterial burden were: i) percent of sites with BOP (r = 0.62); ii) percent of sites with PD ≥ 3 mm (r = 0.61); and iii) number of sites with BOP (r = 0.59). Increasing PD or AL severity thresholds consistently attenuated correlations, i.e., the correlation of bacterial burden with the percent of sites with PD ≥ 8 mm was only r = 0.16. Conclusions Clinical exposure definitions of periodontal disease should incorporate relatively shallow pockets to best reflect whole mouth exposure to bacterial burden. PMID:20056008

Adjunct Antimicrobial Therapy and Periodontal Surgery to Treat Generalized Aggressive Periodontitis: A Case Report.

PubMed

Irokawa, Daisuke; Makino-Oi, Asako; Fujita, Takahisa; Yamamoto, Shigeki; Tomita, Sachiyo; Saito, Atsushi

2016-01-01

Here we report a case of generalized aggressive periodontitis treated with periodontal therapy including adjunct antimicrobial therapy and periodontal surgery. The patient was a 22-year-old woman who presented with the chief complaint of gingival recession. Baseline examination revealed generalized plaque deposition and gingival inflammation. Thirty-nine percent of the sites had a probing depth (PD) of 4-6 mm and 2% a PD of ≥7 mm; 63% exhibited bleeding on probing (BOP). Radiographic examination revealed vertical bone loss in the molars and horizontal bone loss in other teeth. Microbiological examination of subgingival plaque revealed the presence of Aggregatibacter actinomycetemcomitans and Tannerella forsythia. Oral health-related quality of life was assessed as a measure of patient-reported outcome. Based on a clinical diagnosis of generalized aggressive periodontitis, initial periodontal therapy and adjunct antimicrobial therapy were implemented. After reducing inflammation and subgingival bacteria, open flap debridement was performed for teeth with a PD of ≥4 mm. Reevaluation showed no sites with a PD of ≥5 mm, a minimal level of BOP, and a marked reduction in the level of the targeted periodontal pathogens. The patient's oral health-related quality of life was slightly worsened during supportive periodontal therapy (SPT). Implementation of adjunct antimicrobial therapy targeting periodontal pathogens and subsequent periodontal surgery resulted in improvement in periodontal and microbiological parameters. This improvement has been adequately maintained over a 2-year period. However, additional care is necessary to further improve the patient's oral health-related quality of life during SPT.

Java project on periodontal diseases: effect of vitamin C/calcium threonate/citrus flavonoids supplementation on periodontal pathogens, CRP and HbA1c.

PubMed

Amaliya, Amaliya; Laine, Marja L; Loos, Bruno G; Van der Velden, Ubele

2015-12-01

To assess in a periodontally diseased rural population deprived from regular dental care and having poor dietary conditions, the effect of vitamin C/calcium threonate/citrus flavonoids (VitC/Ca/Fl) supplementation on subgingival microbiota and plasma levels of vitamin C, HbA1c and hsCRP. The study population consisted of 98 subjects who previously participated in a prospective study on the natural history of periodontitis. Participants were instructed to consume one tablet/day containing 200 mg Ester C(®) calcium ascorbate, 25 mg calcium threonate and 100 mg citrus flavonoids for 90 days. Following parameters were evaluated: prevalence/amount of seven traditional periodontal pathogens, cytomegalovirus, Epstein-Barr virus (EBV); and plasma levels of vitamin C, HbA1c and hsCRP. After VitC/Ca/Fl supplementation, 100% of subjects showed normal plasma vitamin C values compared to 55% before. At baseline, 48% of subjects harboured Aggregatibacter actinomycetemcomitans, >97% the other periodontal pathogens and 73% EBV. Supplementation with VitC/Ca/F reduced the subgingival load of all studied bacteria (p-values: 0.014-0.0001) and EBV (p < 0.0001) substantially in all initially positive subjects. Plasma levels of HbA1c and hsCRP dropped in all subjects (p < 0.0001). This uncontrolled study suggested that supplemental VitC/Ca/Fl may be helpful in reducing subgingival numbers of periodontal pathogens and EBV, and promoting systemic health. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microbial signature profiles of periodontally healthy and diseased patients.

PubMed

Lourenço, Talita Gomes Baêta; Heller, Débora; Silva-Boghossian, Carina Maciel; Cotton, Sean L; Paster, Bruce J; Colombo, Ana Paula Vieira

2014-11-01

To determine microbial profiles that discriminate periodontal health from different forms of periodontal diseases. Subgingival biofilm was obtained from patients with periodontal health (27), gingivitis (11), chronic periodontitis (35) and aggressive periodontitis (24), and analysed for the presence of >250 species/phylotypes using HOMIM. Microbial differences among groups were examined by Mann-Whitney U-test. Regression analyses were performed to determine microbial risk indicators of disease. Putative and potential new periodontal pathogens were more prevalent in subjects with periodontal diseases than periodontal health. Detection of Porphyromonas endodontalis/Porphyromonas spp. (OR 9.5 [1.2-73.1]) and Tannerella forsythia (OR 38.2 [3.2-450.6]), and absence of Neisseria polysaccharea (OR 0.004 [0-0.15]) and Prevotella denticola (OR 0.014 [0-0.49], p < 0.05) were risk indicators of periodontal disease. Presence of Aggregatibacter actinomycetemcomitans (OR 29.4 [3.4-176.5]), Cardiobacterium hominis (OR 14.9 [2.3-98.7]), Peptostreptococcaceae sp. (OR 35.9 [2.7-483.9]), P. alactolyticus (OR 31.3 [2.1-477.2]), and absence of Fretibacterium spp. (OR 0.024 [0.002-0.357]), Fusobacterium naviforme/Fusobacterium nucleatum ss vincentii (OR 0.015 [0.001-0.223]), Granulicatella adiacens/Granulicatella elegans (OR 0.013 [0.001-0.233], p < 0.05) were associated with aggressive periodontitis. There were specific microbial signatures of the subgingival biofilm that were able to distinguish between microbiomes of periodontal health and diseases. Such profiles may be used to establish risk of disease. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microbial Signature Profiles of Periodontally Healthy and Diseased Patients

PubMed Central

Lourenço, Talita Gomes Baêta; Heller, Débora; da Silva-Boghossian, Carina Maciel; Cotton, Sean L.; Paster, Bruce J.; Colombo, Ana Paula Vieira

2014-01-01

Aim To determine microbial profiles that discriminate periodontal health from different forms of periodontal diseases. Methods Subgingival biofilm was obtained from patients with periodontal health (27), gingivitis (11), chronic periodontitis (35) and aggressive periodontitis (24), and analyzed for the presence of >250 species/phylotypes using HOMIM. Microbial differences among groups were examined by Mann-Whitney. Regression analyses were performed to determine microbial risk indicators of disease. Results Putative and potential new periodontal pathogens were more prevalent in subjects with periodontal diseases than periodontal health. Detection of Porphyromonas endodontalis/Porphyromonas spp. (OR 9.5 [1.2–73.1]) and Tannerella forsythia (OR 38.2 [3.2–450.6]), and absence of Neisseria polysaccharea (OR 0.004 [0–0.15]) and Prevotella denticola (OR 0.014 [0–0.49], p<0.05) were risk indicators of periodontal disease. Presence of Aggregatibacter actinomycetemcomitans (OR 29.4 [3.4–176.5]), Cardiobacterium hominis (OR 14.9 [2.3–98.7]), Peptostreptococcaceae sp. (OR 35.9 [2.7–483.9]), P. alactolyticus (OR 31.3 [2.1–477.2]), and absence of Fretibacterium spp. (OR 0.024 [0.002–0.357]), Fusobacterium naviforme/Fusobacterium nucleatum ss vincentii (OR 0.015 [0.001–0.223]), Granulicatella adiacens/Granulicatella elegans (OR 0.013 [0.001–0.233], p<0.05) were associated with aggressive periodontitis. Conclusion There were specific microbial signatures of the subgingival biofilm that were able to distinguish between microbiomes of periodontal health and diseases. Such profiles may be used to establish risk of disease. PMID:25139407

Peptides: β-cyclodextrin inclusion compounds as highly effective antimicrobial and anti-epithelial proliferation agents.

PubMed

Consuegra, Jessika; de Lima, Maria Elena; Santos, Daniel; Sinisterra, Rubén Dario; Cortés, Maria Esperanza

2013-12-01

The use of antimicrobial peptides (AMPs) as therapeutic agents for periodontal infections has great advantages, such as broad spectrum of action, low toxicity, and limited bacterial resistance. However, their practical use is limited because of the large amount of peptide required to exercise the microbicidal function. LyeTxI, LL37f, and KR12 cationic peptides were prepared with β-cyclodextrin (βCD) at 1:1 molar ratios. The susceptibility of Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum were assessed in anaerobic conditions. Cytotoxicity assays were performed using osteoblast and Caco-2 epithelial cells, and hemolytic activity was assessed on rabbit erythrocytes at an absorbance of 414 nm. Parameters of surface roughness and electrical charge were established by atomic force microscopy and zeta (ζ) potential, respectively. AMP/βCDs drastically decreased the peptide concentration required for activity against the bacteria tested. Moreover, AMPs associated with βCD were able to modify cell-surface parameters, such as roughness and ζ potential. On the other hand, AMP/βCD did not alter the degree of hemolysis induced by the pure AMPs. The effective concentration at half-maximum values of the peptides and compounds on osteoblasts were greater than the concentrations required to achieve inhibition of bacterial growth in all the species tested. AMP/βCDs inhibited the proliferation of Caco-2 epithelial cells in a more efficient manner than AMPs alone. AMP/βCD compounds more effectively inhibit periodontopathogenic bacteria than AMPs alone, with the additional ability of inhibiting the proliferation of epithelial cells at concentrations that are non-cytotoxic for osteoblasts and erythrocytes.

Oral pathogens change proliferation properties of oral tumor cells by affecting gene expression of human defensins.

PubMed

Hoppe, T; Kraus, D; Novak, N; Probstmeier, R; Frentzen, M; Wenghoefer, M; Jepsen, S; Winter, J

2016-10-01

The impact of oral pathogens onto the generation and variability of oral tumors has only recently been investigated. To get further insights, oral cancer cells were treated with pathogens and additionally, as a result of this bacterial cellular infection, with human defensins, which are as anti-microbial peptide members of the innate immune system. After cell stimulation, proliferation behavior, expression analysis of oncogenic relevant defensin genes, and effects on EGFR signaling were investigated. The expression of oncogenic relevant anti-microbial peptides was analyzed with real-time PCR and immunohistochemistry. Cell culture experiments were performed to examine cellular impacts caused by stimulation, i.e., altered gene expression, proliferation rate, and EGF receptor-dependent signaling. Incubation of oral tumor cells with an oral pathogen (Porphyromonas gingivalis) and human α-defensins led to an increase in cell proliferation. In contrast, another oral bacterium used, Aggregatibacter actinomycetemcomitans, enhanced cell death. The bacteria and anti-microbial peptides exhibited diverse effects on the transcript levels of oncogenic relevant defensin genes and epidermal growth factor receptor signaling. These two oral pathogens exhibited opposite primary effects on the proliferation behavior of oral tumor cells. Nevertheless, both microbe species led to similar secondary impacts on the proliferation rate by modifying expression levels of oncogenic relevant α-defensin genes. In this respect, oral pathogens exerted multiplying effects on tumor cell proliferation. Additionally, human defensins were shown to differently influence epidermal growth factor receptor signaling, supporting the hypothesis that these anti-microbial peptides serve as ligands of EGFR, thus modifying the proliferation behavior of oral tumor cells.

Generalized aggressive periodontitis: microbiological composition and clinical parameters in non-surgical therapy.

PubMed

Usin, María M; Tabares, Sandra M; Menso, Julieta; de Albera, Estela R; Sembaj, Adela

2016-12-01

The aim of this study was to determine the variations in periodontal parameters and microbiological composition in periodontal pockets at the baseline and 3 and 6 months post treatmentin patients with Generalized Aggressive Periodontitis(GAP) undergoing non surgical periodontal treatment combined with chlorhexidine and systemic antibiotics. Medical and dental history was taken from 10 subjects, average age 30.6±2.7 years, diagnosed with GAP. A non surgical periodontal treatment combined with 0.12% chlorhexidine, 875 mg amoxicillin and 500 mg metronidazole every 12 hours for ten days was conducted. At each visit, the following measurements wererecorded: bacterial plaque (BP), bleeding on probing (BOP), probing depth (PD), clinical attachment level (CAL), hypermobility, and furcation lesions, and a sample of subgingivalplaque was taken from the site of the deepest probing depth of each sextant to identify Porphyromonas gingivalis, Treponemadenticola, Tannerella forsythia, Prevotella intermedia and Aggregatibacter actinomycetemcomitans using molecular biology techniques. After 6 months, the Wilcoxon test showed an increase of 0.97 mm in CAL (p=0.0047) and 2.54 mm in PD(p=0.009). A healthy site was defined as having a PD <5 mm, negative BOP and no pathogenic bacteria detected at 6 months, indicating significant improvement (p=0.008), with OR (95%CI) =4.7 (1.102220.11).With the treatment protocol used in this study, 6 months after treatment, patients had an approximately 4- fold higher possibility of presenting PD <5 mm and periodontal pockets without periodontal pathogenic bacteria. Sociedad Argentina de Investigación Odontológica.

Effect of Periodontal Pathogens on the Metatranscriptome of a Healthy Multispecies Biofilm Model

PubMed Central

Duran-Pinedo, Ana

2012-01-01

Oral bacterial biofilms are highly complex microbial communities with up to 700 different bacterial taxa. We report here the use of metatranscriptomic analysis to study patterns of community gene expression in a multispecies biofilm model composed of species found in healthy oral biofilms (Actinomyces naeslundii, Lactobacillus casei, Streptococcus mitis, Veillonella parvula, and Fusobacterium nucleatum) and the same biofilm plus the periodontopathogens Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. The presence of the periodontopathogens altered patterns in gene expression, and data indicate that transcription of protein-encoding genes and small noncoding RNAs is stimulated. In the healthy biofilm hypothetical proteins, transporters and transcriptional regulators were upregulated while chaperones and cell division proteins were downregulated. However, when the pathogens were present, chaperones were highly upregulated, probably due to increased levels of stress. We also observed a significant upregulation of ABC transport systems and putative transposases. Changes in Clusters of Orthologous Groups functional categories as well as gene set enrichment analysis based on Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways showed that in the absence of pathogens, only sets of proteins related to transport and secondary metabolism were upregulated, while in the presence of pathogens, proteins related to growth and division as well as a large portion of transcription factors were upregulated. Finally, we identified several small noncoding RNAs whose predicted targets were genes differentially expressed in the open reading frame libraries. These results show the importance of pathogens controlling gene expression of a healthy oral community and the usefulness of metatranscriptomic techniques to study gene expression profiles in complex microbial community models. PMID:22328675

Effect of Periodontitis on Adiponectin, C-Reactive Protein, and Immunoglobulin G Against Porphyromonas gingivalis in Thai People With Overweight or Obese Status.

PubMed

Thanakun, Supanee; Izumi, Yuichi

2016-05-01

Obesity and periodontitis are associated with an inflammatory background. Inflammatory mediators involved may have reciprocal effects on one another. In this study, the levels of inflammatory mediators implicated in overweight or obese status and periodontitis are simultaneously evaluated. Body mass index (BMI) and waist circumference, periodontal disease status, and plasma levels of adiponectin, leptin, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule 1, C-reactive protein (CRP), immunoglobulin (Ig)G antibody against Porphyromonas gingivalis, and IgG against Aggregatibacter actinomycetemcomitans in 109 periodontitis participants with various BMIs were measured. BMI ≥23.0 kg/m(2) was considered overweight or obese. Plasma adiponectin was decreased (P = 0.04), whereas CRP and IgG against P. gingivalis were increased (P = 0.04 and P = 0.001, respectively) in patients with severe periodontitis compared with patients with mild or moderate periodontitis, independent of overweight or obese status. Plasma CRP, ICAM-1, and leptin were increased (P <0.001, P = 0.007, and P <0.001, respectively) and adiponectin was decreased (P = 0.04) in overweight or obese participants compared with normal weight participants, without influence of periodontitis severity. No interaction effect between periodontitis and overweight or obese status existed for these protein levels after the data were adjusted for age, sex, plasma levels of triglycerides, high-density lipoprotein cholesterol, fasting plasma glucose, and blood pressure (P = 0.48). Periodontitis and overweight or obese BMI change plasma levels of the inflammatory mediators adiponectin and CRP, independently. This study suggests a role of periodontitis in systemic inflammatory response in Thai people who are overweight or obese.

Effect of Helicobacter pylori infection on chronic periodontitis by the change of microecology and inflammation

PubMed Central

Hu, Zhekai; Zhang, Yu; Li, Zhiyu; Yu, Yuedi; Kang, Wenyan; Han, Yingnan; Geng, Xiwen; Ge, Shaohua; Sun, Yundong

2016-01-01

Helicobacter pylori (H. pylori), a pathogen inducing peptic disease, is recently found to be binding to the progress of periodontitis. Most previous studies are case-controlled, and they investigate the risk of H. pylori infection in disease the development of while few studies evaluate the correlation between H. pylori and periodontal pathogens. Therefore, we investigated the correlation between H. pylori infection with periodontal parameters, periodontal pathogens and inflammation. The results indicated that patients with H. pylori showed significantly higher probing depth and attachment loss than those without (p < 0.05). Among 28 subgingival plaque samples from 14 patients, the frequencies of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Treponema denticola were significantly higher with H. pylori infection than those without H. pylori infection (p < 0.05). However, the frequency of Aggregatibacter actinomycetemcomitans was lower (p < 0.05). Furthermore, after human acute monocytic leukemia cell line (THP-1) was stimulated with cagA-positive standard strains (cagA+ H. pylori 26695), the expression of periodontitis-related molecules Wnt5a, interleukin 8 (IL-8), interleukin 6 (IL-6) and interferon gamma (IFN-γ) significantly increased (p < 0.05). Conversely, the expression of tumor necrosis factor alpha (TNF-α) was almost stable. Meanwhile, cagA+ H. pylori promoted significantly higher expression of IL-8 and Wnt5a than isogenic cagA mutants strains (cagA− H. pylori 26695) did. Taken together, our data suggested that H. pylori might promote the growth of some periodontal pathogens and aggravate the progress of chronic periodontitis. PMID:27602578

Effect of Helicobacter pylori infection on chronic periodontitis by the change of microecology and inflammation.

PubMed

Hu, Zhekai; Zhang, Yu; Li, Zhiyu; Yu, Yuedi; Kang, Wenyan; Han, Yingnan; Geng, Xiwen; Ge, Shaohua; Sun, Yundong

2016-10-11

Helicobacter pylori (H. pylori), a pathogen inducing peptic disease, is recently found to be binding to the progress of periodontitis. Most previous studies are case-controlled, and they investigate the risk of H. pylori infection in disease the development of while few studies evaluate the correlation between H. pylori and periodontal pathogens. Therefore, we investigated the correlation between H. pylori infection with periodontal parameters, periodontal pathogens and inflammation. The results indicated that patients with H. pylori showed significantly higher probing depth and attachment loss than those without (p < 0.05). Among 28 subgingival plaque samples from 14 patients, the frequencies of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Treponema denticola were significantly higher with H. pylori infection than those without H. pylori infection (p < 0.05). However, the frequency of Aggregatibacter actinomycetemcomitans was lower (p < 0.05). Furthermore, after human acute monocytic leukemia cell line (THP-1) was stimulated with cagA-positive standard strains (cagA+ H. pylori 26695), the expression of periodontitis-related molecules Wnt5a, interleukin 8 (IL-8), interleukin 6 (IL-6) and interferon gamma (IFN-γ) significantly increased (p < 0.05). Conversely, the expression of tumor necrosis factor alpha (TNF-α) was almost stable. Meanwhile, cagA+ H. pylori promoted significantly higher expression of IL-8 and Wnt5a than isogenic cagA mutants strains (cagA- H. pylori 26695) did. Taken together, our data suggested that H. pylori might promote the growth of some periodontal pathogens and aggravate the progress of chronic periodontitis.

Association of Porphyromonas gingivalis with high levels of stress-induced hormone cortisol in chronic periodontitis patients.

PubMed

Ardila, Carlos M; Guzmán, Isabel C

2016-11-01

The aim of the present study was to evaluate the association between the occurrence of periodontopathogens with cortisol levels in chronic periodontitis patients. Seventy-five chronic periodontitis patients were invited to participate in the present study. Cortisol levels in serum were measured using an immunoassay method. Porphyromonas gingivalis (P. gingivalis) Tannerella forsythia, Treponema denticola, and Aggregatibacter actinomycetemcomitans were detected by polymerase chain reaction using primers designed to target the respective 16S rRNA gene sequences. Severe chronic periodontitis patients showed higher mean levels of cortisol (P < 0.05). Twenty-six patients had hypercortisolemia. High cortisol levels showed a positive significant correlation with P. gingivalis (r = 0.237, P < 0.01). Of the 26 patients with hypercortisolemia, 81% had P. gingivalis, of which 86% had severe chronic periodontitis (P < 0.001). There were higher levels of cortisol with the presence of P. gingivalis (478.65 ± 122.57 vs 402.58 ± 139.60, P = 0.01). The adjusted logistic regression model showed a significant association between high cortisol levels and P. gingivalis (odds ratio = 1.7, 95% confidence interval = 1.6-1.8). This research offers support for the association between P. gingivalis and higher levels of cortisol in chronic periodontitis patients. These results suggest that high levels of cortisol could increase the occurrence of P. gingivalis in the biofilm. © 2015 Wiley Publishing Asia Pty Ltd.

Microbiological and clinical assessment of the abutment and non-abutment teeth of partial removable denture wearers.

PubMed

Costa, Luciana; do Nascimento, Cássio; de Souza, Valéria Oliveira Pagnano; Pedrazzi, Vinícius

2017-03-01

The aim of this study was assessing the changes in both clinical and microbiological parameters of healthy individuals after rehabilitation with removable partial denture (RPD). 11 women received unilateral or bilateral free-end saddle RPD in the mandibular arch. Clinical and microbiological parameters of abutment, non-abutment, and antagonist teeth were assessed at baseline (RPD installation) and after 7, 30, 90, and 180days of function. The Checkerboard DNA-DNA hybridization technique was used to identify and quantify up to 43 different microbial species from subgingival biofilm samples. Probing depth, gingival recession, and bleeding on probing were also investigated over time. The total and individual microbial genome counts were shown significantly increased after 180days with no significant differences between abutment, non-abutment, or antagonist teeth. Streptococcus spp., Aggregatibacter actinomycetemcomitans, and other species associated to periodontitis (Peptostreptococcus anaerobius, Prevotella nigrescens, and Tannerella forsythia), as well as opportunistic Candida spp., were recovered in moderate counts. Abutment teeth presented higher values of gingival recession when compared with non-abutment or antagonist teeth, irrespectively time of sampling (p<0.05). No significant differences were found between groups regarding bleeding on probing or probing depth over time. Overall, the microbial counts significantly increased after 6 months of denture loading for both abutment and non-abutment teeth with no significant differences regarding the microbial profile over time. Bleeding on probing and probing depth showed no significant difference between groups over time whereas gingival recession increased in the abutment teeth. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of Riboflavin and Toluidine Blue O as Photosensitizers for Photoactivated Disinfection on Endodontic and Periodontal Pathogens In Vitro.

PubMed

Nielsen, Henrik Krarup; Garcia, Javier; Væth, Michael; Schlafer, Sebastian

2015-01-01

Photoactivated disinfection has a strong local antimicrobial effect. In the field of dentistry it is an emerging adjunct to mechanical debridement during endodontic and periodontal treatment. In the present study, we investigate the effect of photoactivated disinfection using riboflavin as a photosensitizer and blue LED light for activation, and compare it to photoactivated disinfection with the widely used combination of toluidine blue O and red light. Riboflavin is highly biocompatible and can be activated with LED lamps at hand in the dental office. To date, no reports are available on the antimicrobial effect of photoactivated disinfection using riboflavin/blue light on oral microorganisms. Planktonic cultures of eight organisms frequently isolated from periodontal and/or endodontic lesions (Aggregatibacter actinomycetemcomitans, Candida albicans, Enterococcus faecalis, Escherischia coli, Lactobacillus paracasei, Porphyromonas gingivalis, Prevotella intermedia and Propionibacterium acnes) were subjected to photoactivated disinfection with riboflavin/blue light and toluidine blue O/red light, and survival rates were determined by CFU counts. Within the limited irradiation time of one minute, photoactivated disinfection with riboflavin/blue light only resulted in minor reductions in CFU counts, whereas full kills were achieved for all organisms when using toluidine blue O/red light. The black pigmented anaerobes P. gingivalis and P. intermedia were eradicated completely by riboflavin/blue light, but also by blue light treatment alone, suggesting that endogenous chromophores acted as photosensitizers in these bacteria. On the basis of our results, riboflavin cannot be recommended as a photosensitizer used for photoactivated disinfection of periodontal or endodontic infections.

Role and Regulation of the Flp/Tad Pilus in the Virulence of Pectobacterium atrosepticum SCRI1043 and Pectobacterium wasabiae SCC3193

PubMed Central

Nykyri, Johanna; Mattinen, Laura; Niemi, Outi; Adhikari, Satish; Kõiv, Viia; Somervuo, Panu; Fang, Xin; Auvinen, Petri; Mäe, Andres; Palva, E. Tapio; Pirhonen, Minna

2013-01-01

In this study, we characterized a putative Flp/Tad pilus-encoding gene cluster, and we examined its regulation at the transcriptional level and its role in the virulence of potato pathogenic enterobacteria of the genus Pectobacterium. The Flp/Tad pilus-encoding gene clusters in Pectobacterium atrosepticum, Pectobacterium wasabiae and Pectobacterium aroidearum were compared to previously characterized flp/tad gene clusters, including that of the well-studied Flp/Tad pilus model organism Aggregatibacter actinomycetemcomitans, in which this pilus is a major virulence determinant. Comparative analyses revealed substantial protein sequence similarity and open reading frame synteny between the previously characterized flp/tad gene clusters and the cluster in Pectobacterium, suggesting that the predicted flp/tad gene cluster in Pectobacterium encodes a Flp/Tad pilus-like structure. We detected genes for a novel two-component system adjacent to the flp/tad gene cluster in Pectobacterium, and mutant analysis demonstrated that this system has a positive effect on the transcription of selected Flp/Tad pilus biogenesis genes, suggesting that this response regulator regulate the flp/tad gene cluster. Mutagenesis of either the predicted regulator gene or selected Flp/Tad pilus biogenesis genes had a significant impact on the maceration ability of the bacterial strains in potato tubers, indicating that the Flp/Tad pilus-encoding gene cluster represents a novel virulence determinant in Pectobacterium. Soft-rot enterobacteria in the genera Pectobacterium and Dickeya are of great agricultural importance, and an investigation of the virulence of these pathogens could facilitate improvements in agricultural practices, thus benefiting farmers, the potato industry and consumers. PMID:24040039

Role and regulation of the Flp/Tad pilus in the virulence of Pectobacterium atrosepticum SCRI1043 and Pectobacterium wasabiae SCC3193.

PubMed

Nykyri, Johanna; Mattinen, Laura; Niemi, Outi; Adhikari, Satish; Kõiv, Viia; Somervuo, Panu; Fang, Xin; Auvinen, Petri; Mäe, Andres; Palva, E Tapio; Pirhonen, Minna

2013-01-01

In this study, we characterized a putative Flp/Tad pilus-encoding gene cluster, and we examined its regulation at the transcriptional level and its role in the virulence of potato pathogenic enterobacteria of the genus Pectobacterium. The Flp/Tad pilus-encoding gene clusters in Pectobacterium atrosepticum, Pectobacterium wasabiae and Pectobacterium aroidearum were compared to previously characterized flp/tad gene clusters, including that of the well-studied Flp/Tad pilus model organism Aggregatibacter actinomycetemcomitans, in which this pilus is a major virulence determinant. Comparative analyses revealed substantial protein sequence similarity and open reading frame synteny between the previously characterized flp/tad gene clusters and the cluster in Pectobacterium, suggesting that the predicted flp/tad gene cluster in Pectobacterium encodes a Flp/Tad pilus-like structure. We detected genes for a novel two-component system adjacent to the flp/tad gene cluster in Pectobacterium, and mutant analysis demonstrated that this system has a positive effect on the transcription of selected Flp/Tad pilus biogenesis genes, suggesting that this response regulator regulate the flp/tad gene cluster. Mutagenesis of either the predicted regulator gene or selected Flp/Tad pilus biogenesis genes had a significant impact on the maceration ability of the bacterial strains in potato tubers, indicating that the Flp/Tad pilus-encoding gene cluster represents a novel virulence determinant in Pectobacterium. Soft-rot enterobacteria in the genera Pectobacterium and Dickeya are of great agricultural importance, and an investigation of the virulence of these pathogens could facilitate improvements in agricultural practices, thus benefiting farmers, the potato industry and consumers.

Transcriptional activation of the tad type IVb pilus operon by PypB in Yersinia enterocolitica.

PubMed

Schilling, Jennifer; Wagner, Karin; Seekircher, Stephanie; Greune, Lilo; Humberg, Verena; Schmidt, M Alexander; Heusipp, Gerhard

2010-07-01

Type IV pili are virulence factors in various bacteria and mediate, among other functions, the colonization of diverse surfaces. Various subclasses of type IV pili have been identified, but information on pilus expression, biogenesis, and the associated phenotypes is sparse for the genus Yersinia. We recently described the identification of PypB as a transcriptional regulator in Yersinia enterocolitica. Here we show that the pypB gene is associated with the tad locus, a genomic island that is widespread among bacterial and archaeal species. The genetic linkage of pypB with the tad locus is conserved throughout the yersiniae but is not found among other bacteria carrying the tad locus. We show that the genes of the tad locus form an operon in Y. enterocolitica that is controlled by PypB and that pypB is part of this operon. The tad genes encode functions necessary for the biogenesis of the Flp subfamily of type IVb pili initially described for Aggregatibacter actinomycetemcomitans to mediate a tight-adherence phenotype. In Y. enterocolitica, the Flp pilin protein shows some peculiarities in its amino acid sequence that imply similarities as well as differences compared to typical motifs found in the Flp subtype of type IVb pili. Flp is expressed and processed after PypB overproduction, resulting in microcolony formation but not in increased adherence to biotic or abiotic surfaces. Our data describe the transcriptional regulation of the tad type IVb pilus operon by PypB in Y. enterocolitica but fail to show most previously described phenotypes associated with this type of pilus in other bacteria.

Anaerobic culture to detect periodontal and caries pathogens

PubMed Central

Tanner, Anne C. R.

2014-01-01

Background Anaerobic culture has been critical in our understanding of the oral microbiotas. Highlight Studies in advanced periodontitis in the 1970’s revealed microbial complexes that associated with different clinical presentations. Taxonomy studies identified species newly-observed in periodontitis as Aggregatibacter (Actinobacillus) actinomycetemcomitans, Campylobacter (Wolinella) rectus and other Campylobacter species, and Tannerella (Bacteroides) forsythia. Anaerobic culture of initial periodontitis showed overlap in the microbiota with gingivitis, and added Selenomonas noxia and Filifactor alocis as putative periodontal pathogens. Porphyromonas gingivalis and T. forsythia were found to be associated with initial periodontitis in adults. The dominant microbiota of dental caries differs from that of periodontitis. The major cariogenic species are acidogenic and acid tolerant species particularly Streptococcus mutans, and Lactobacillus and Bifidobacterium species. Anaerobic culture of severe early childhood caries revealed a widely diverse microbiota, comparable to that observed using cloning and sequencing. The PCR-based cloning approach, however, underestimated Actinobacteria compared with culture. Only a subset of the caries-associated microbiota was acid tolerant, with different segments of the microbiota cultured on blood agar compared to a low pH acid agar. While the major caries-associated species was S. mutans, a new species, Scardovia wiggsiae, was significantly associated with early childhood caries. Higher counts of S. wiggsiae were also observed in initial white spot carious lesions in adolescents. Conclusion In periodontitis and dental caries, anaerobic culture studies of advanced disease provided a comprehensive analysis of the microbiota of these infections. Anaerobic culture highlighted the limitation of PCR with standard primers that underestimate detection of Actinobacteria. PMID:25678835

Changes in salivary periodontal pathogens after orthodontic treatment: An in vivo prospective study.

PubMed

Kim, Kyungsun; Jung, Woo-Sun; Cho, Soha; Ahn, Sug-Joon

2016-11-01

  To analyze the initial changes in salivary levels of periodontal pathogens after orthodontic treatment with fixed appliances.   The subjects consisted of 54 adult patients. The Simplified Oral Hygiene Index, Plaque Index, and Gingival Index were measured as periodontal parameters. Both the plaque and gingival indexes were obtained from the central and lateral incisors and first molars of both arches. Whole saliva and periodontal parameters were obtained at the following four time points: immediately before debonding (T1), 1 week after debonding (T2), 5 weeks after debonding (T3), and 13 weeks after debonding (T4). Repeated measures analysis of variance was used to determine salivary bacterial levels and periodontal parameters among the four time points after quantifying salivary levels of Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf), and total bacteria using the real-time polymerase chain reaction.   All periodontal parameters were significantly decreased immediately after debonding (T2). The salivary levels of total bacteria and Pg were decreased at T3, while Pi and Tf levels were decreased at T4. However, the amount of Aa and Fn remained at similar levels in saliva during the experimental period. Interestingly, Aa and Fn were present in saliva at higher levels than were Pg, Pi, and Tf.   The higher salivary levels of Aa and Fn after debonding suggests that the risk of periodontal problems cannot be completely eliminated by the removal of fixed orthodontic appliances during the initial retention period, despite improved oral hygiene.

Frequency of periodontal pathogens and Helicobacter pylori in the mouths and stomachs of obese individuals submitted to bariatric surgery: a cross-sectional study

PubMed Central

PATARO, André Luiz; CORTELLI, Sheila Cavalca; ABREU, Mauro Henrique Nogueira Guimarães; CORTELLI, José Roberto; FRANCO, Gilson Cesar Nobre; AQUINO, Davi Romeiro; COTA, Luis Otavio Miranda; COSTA, Fernando Oliveira

2016-01-01

ABSTRACT Objectives This cross-sectional study compared the frequency of oral periodontopathogens and H. pylori in the mouths and stomachs of obese individuals with or without periodontitis submitted to bariatric surgery. Material and Methods One hundred and fifty-four men and women aged 18-65 were conveniently distributed into four groups. Two groups were composed of individuals who underwent bariatric surgery with (BP) (n=40) and without (BNP) (n=39) periodontitis and two obese control groups with (CP) (n=35) and without (CNP) (n=40) periodontitis. The oral pathogens Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Parvimonas micra, Treponema denticola, Tannerella forsythia, Campylobacter rectus, and Helicobacter pylori were detected by a polymerase chain reaction technique using saliva, tongue and stomach biopsy samples. Results Statistical analysis demonstrated that periodontopathogens were highly frequent in the mouth (up to 91.4%). In the bariatric surgically treated group, orally, P. gingivalis, T. denticola and T. forsythia were more frequent in periodontitis, while C. rectus was more frequent in non-periodontitis subjects. Stomach biopsies also revealed the high frequency of five oral species in both candidates for bariatric surgery (91.6%) and the bariatric (83.3%) groups. H. pylori was frequently detected in the mouth (50.0%) and stomach (83.3%). In the stomach, oral species and H. pylori appeared in lower frequency in the bariatric group. Conclusions Obese individuals showed high frequencies of periodontopathogens and H. pylori in their mouths and stomachs. Bariatric surgery showed an inverse microbial effect on oral and stomach environments by revealing higher oral and lower stomach bacterial frequencies. PMID:27383704

Site-level progression of periodontal disease during a follow-up period

PubMed Central

Morozumi, Toshiya; Nakagawa, Taneaki; Sugaya, Tsutomu; Kawanami, Masamitsu; Suzuki, Fumihiko; Takahashi, Keiso; Abe, Yuzo; Sato, Soh; Makino-Oi, Asako; Saito, Atsushi; Takano, Satomi; Minabe, Masato; Nakayama, Yohei; Ogata, Yorimasa; Kobayashi, Hiroaki; Izumi, Yuichi; Sugano, Naoyuki; Ito, Koichi; Sekino, Satoshi; Numabe, Yukihiro; Fukaya, Chie; Yoshinari, Nobuo; Fukuda, Mitsuo; Noguchi, Toshihide; Kono, Tomoo; Umeda, Makoto; Fujise, Osamu; Nishimura, Fusanori; Yoshimura, Atsutoshi; Hara, Yoshitaka; Nakamura, Toshiaki; Noguchi, Kazuyuki; Kakuta, Erika; Hanada, Nobuhiro; Takashiba, Shogo; Amitani, Yasuharu; Yoshie, Hiromasa

2017-01-01

Periodontal disease is assessed and its progression is determined via observations on a site-by-site basis. Periodontal data are complex and structured in multiple levels; thus, applying a summary statistical approach (i.e., the mean) for site-level evaluations results in loss of information. Previous studies have shown the availability of mixed effects modeling. However, clinically beneficial information on the progression of periodontal disease during the follow-up period is not available. We conducted a multicenter prospective cohort study. Using mixed effects modeling, we analyzed 18,834 sites distributed on 3,139 teeth in 124 patients, and data were collected 5 times over a 24-month follow-up period. The change in the clinical attachment level (CAL) was used as the outcome variable. The CAL at baseline was an important determinant of the CAL changes, which varied widely according to the tooth surface. The salivary levels of periodontal pathogens, such as Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans, were affected by CAL progression. “Linear”- and “burst”-type patterns of CAL progression occurred simultaneously within the same patient. More than half of the teeth that presented burst-type progression sites also presented linear-type progression sites, and most of the progressions were of the linear type. Maxillary premolars and anterior teeth tended to show burst-type progression. The parameters identified in this study may guide practitioners in determining the type and extent of treatment needed at the site and patient levels. In addition, these results show that prior hypotheses concerning "burst" and "linear" theories are not valid. PMID:29206238

Activity of antimicrobial peptide mimetics in the oral cavity: II. Activity against periopathogenic biofilms and anti-inflammatory activity

PubMed Central

Hua, J; Scott, R.W.; Diamond, G

2011-01-01

Whereas periodontal disease is ultimately of bacterial etiology, from multispecies biofilms of gram-negative anaerobic microorganisms, much of the deleterious effects are caused by the resultant epithelial inflammatory response. Hence, development of a treatment that combines anti-biofilm antibiotic activity with anti-inflammatory activity would be of great utility. Antimicrobial peptides (AMPs) such as defensins are naturally occurring peptides that exhibit broad-spectrum activity as well as a variety of immunomodulatory activities. Furthermore, bacteria do not readily develop resistance to these agents. However, clinical studies have suggested that they do not represent optimal candidates for exogenous therapeutic agents. Small-molecule mimetics of these AMPs exhibit similar activities to the parent peptides, in addition to having low toxicity, high stability and low cost. To determine whether AMP mimetics have the potential for treatment of periodontal disease, we examined the activity of one mimetic, mPE, against biofilm cultures of Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis. Metabolic assays as well as culture and biomass measurement assays demonstrated that mPE exhibits potent activity against biofilm cultures of both species. Furthermore, as little as 2 µg ml−1 mPE was sufficient to inhibit interleukin-1β-induced secretion of interleukin-8 in both gingival epithelial cells and THP-1 cells. This anti-inflammatory activity is associated with a reduction in activation of nuclear factor-κB, suggesting that mPE can act both as an anti-biofilm agent in an anaerobic environment and as an anti-inflammatory agent in infected tissues. PMID:21040516

Structure and biosynthesis of free lipid A molecules that replace lipopolysaccharide in Francisella novicida

PubMed Central

Wang, Xiaoyuan; Ribeiro, Anthony A.; Guan, Ziqiang; McGrath, Sara C.; Cotter, Robert J.; Raetz, Christian R. H.

2008-01-01

Francisella novicida U112 phospholipids, extracted without hydrolysis, consist mainly of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine, and two lipid A species, designated A1 and A2. These lipid A species, present in a ratio of 7:1, comprise 15 % of the total phospholipids, as judged by 32Pi labeling. Although lipopolysaccharide is detectable in F. novicida U112, less than 5 % of the total lipid A is covalently linked to it. A1 and A2 were analyzed by electrospray ionization and matrix-assisted laser desorption ionization mass spectrometry, gas chromatography/mass spectrometry and NMR spectroscopy. Both compounds are disaccharides of glucosamine, acylated with primary 3-hydroxystearoyl chains at positions 2, 3, and 2′, and a secondary palmitoyl residue at position 2′. Minor isobaric species and some lipid A molecules containing a 3-hydroxypalmitoyl chain in place of 3-hydroxystearate are also present. The 4′- and 3′-positions of A1 and A2 are not derivatized, and Kdo is not detectable. The 1-phosphate groups of both A1 and A2 are modified with an α-linked galactosamine residue, as shown by NMR spectroscopy and gas chromatography/mass spectrometry. An α-linked glucose moiety is attached to the 6′-position of A2. The lipid A released by mild acid hydrolysis of F. novicida lipopolysaccharide consists solely of component A1. F. novicida mutants lacking the arnT gene do not contain a galactosamine residue on their lipid A. Formation of free lipid A in F. novicida might be initiated by an unusual Kdo hydrolase present in the membranes of this organism. PMID:17128982

n-Butanol extract from Folium isatidis inhibits lipopolysaccharide-induced inflammatory cytokine production in macrophages and protects mice against lipopolysaccharide-induced endotoxic shock

PubMed Central

Jiang, Lili; Lu, Yili; Jin, Jiahui; Dong, Lili; Xu, Fengli; Chen, Shuangshuang; Wang, Zhanyue; Liang, Guang; Shan, Xiaoou

2015-01-01

Sepsis, which is caused by severe infection, is an important cause of mortality, but effective clinical treatment against sepsis is extremely limited. As the main component of the outer membrane of Gram-negative bacteria, lipopolysaccharide (LPS) plays a major role in inflammatory responses. Studies have shown beneficial pharmacological effects for Folium isatidis. The present study further illuminated the effects of n-butanol extract from Folium isatidis in LPS-induced septic shock and identified the main active chemical components. Our study showed that pretreatment with n-butanol extract from Folium isatidis not only significantly inhibited LPS-induced tumor necrosis factor-α and interleukin-6 production but also markedly and dose dependently enhanced the recruitment of MyD88, the phosphorylation of extracellular signal-regulated kinase, and the degradation of IκB-α. Additionally, the extract exhibited dramatic protective effects against lung injury and death in mice with septic shock. Eight main active compounds were identified, including organic acids, glycoside, indolinones, and flavonoids. These findings provide a perspective on the respiratory protection offered by n-butanol extract from Folium isatidis in LPS-induced sepsis and outline a novel therapeutic strategy for the treatment of sepsis. PMID:26491261

Resurrecting Inactive Antimicrobial Peptides from the Lipopolysaccharide Trap

PubMed Central

Mohanram, Harini

2014-01-01

Host defense antimicrobial peptides (AMPs) are a promising source of antibiotics for the treatment of multiple-drug-resistant pathogens. Lipopolysaccharide (LPS), the major component of the outer leaflet of the outer membrane of Gram-negative bacteria, functions as a permeability barrier against a variety of molecules, including AMPs. Further, LPS or endotoxin is the causative agent of sepsis killing 100,000 people per year in the United States alone. LPS can restrict the activity of AMPs inducing aggregations at the outer membrane, as observed for frog AMPs, temporins, and also in model AMPs. Aggregated AMPs, “trapped” by the outer membrane, are unable to traverse the cell wall, causing their inactivation. In this work, we show that these inactive AMPs can overcome LPS-induced aggregations while conjugated with a short LPS binding β-boomerang peptide motif and become highly bactericidal. The generated hybrid peptides exhibit activity against Gram-negative and Gram-positive bacteria in high-salt conditions and detoxify endotoxin. Structural and biophysical studies establish the mechanism of action of these peptides in LPS outer membrane. Most importantly, this study provides a new concept for the development of a potent broad-spectrum antibiotic with efficient outer membrane disruption as the mode of action. PMID:24419338

Benzoxazole derivatives suppress lipopolysaccharide-induced mast cell activation.

PubMed

Cho, Kyung-Ah; Park, Minhwa; Kim, Yu-Hee; Choo, Hea-Young Park; Lee, Kyung Ho

2018-05-01

Mast cells are central regulators of allergic inflammation that function by releasing various proallergic inflammatory mediators, including histamine, eicosanoids and proinflammatory cytokines. Occasionally, bacterial infections may initiate or worsen allergic inflammation. A number of studies have indicated that activation of lipoxygenase in mast cells positive regulates allergic inflammatory responses by generating leukotrienes and proinflammatory cytokines. In the present study, the effects of benzoxazole derivatives on the lipopolysaccharide (LPS)‑induced expression of proinflammatory cytokines, production of histamine and surface expression of co‑stimulatory molecules on bone marrow-derived mast cells (BMMCs) were studied. The benzoxazole derivatives significantly reduced the expression of interleukin (IL)‑1β, IL‑6, IL‑13, tumor necrosis factor‑α, perilipin (PLIN) 2, and PLIN3 in BMMCs treated with LPS. Furthermore, histamine production was suppressed in BMMCs treated with LPS, or treated with phorbol-12-myristate-13-acetate/ionomycin. Benzoxazole derivatives marginally affected the surface expression of cluster of differentiation (CD)80 and CD86 on BMMCs in the presence of LPS, although LPS alone did not increase the expression of those proteins. Therefore, benzoxazole derivatives inhibited the secretion of proinflammatory cytokines in mast cells and may be potential candidate anti‑allergic agents to suppress mast cell activation.

The lipopolysaccharide lipid-a long chain fatty acid is important for rhizobium leguminosarum growth and stress adaptation in free-living and nodule environments

USDA-ARS?s Scientific Manuscript database

Rhizobium bacteria live in soil and plant environments, are capable of inducing symbiotic nodules on legumes, invade these nodules, and develop into bacteroids that fix atmospheric nitrogen into ammonium. Lipopolysaccharide (LPS) is anchored in the bacterial outer membrane through a specialized lipi...

Effects of intravenous lipopolysaccharide infusion on glucose and insulin dynamics in horses with equine metabolic syndrome.

PubMed

Tadros, Elizabeth M; Frank, Nicholas; De Witte, Fiamma Gomez; Boston, Raymond C

2013-07-01

To test the hypothesis that glucose and insulin dynamics during endotoxemia differ between healthy horses and horses with equine metabolic syndrome (EMS). 6 healthy adult mares and 6 horses with EMS. Each horse randomly received an IV infusion of lipopolysaccharide (20 ng/kg [in 60 mL of sterile saline {0.9% NaCl} solution]) or saline solution, followed by the other treatment after a 7-day washout period. Baseline insulin-modified frequently sampled IV glucose tolerance tests were performed 27 hours before and then repeated at 0.5 and 21 hours after infusion. Results were assessed via minimal model analysis and area under the curve values for plasma glucose and serum insulin concentrations. Lipopolysaccharide infusion decreased insulin sensitivity and increased area under the serum insulin concentration curve (treatment × time) in both healthy and EMS-affected horses, compared with findings following saline solution administration. The magnitude of increase in area under the plasma glucose curve following LPS administration was greater for the EMS-affected horses than it was for the healthy horses. Horses with EMS that received LPS or saline solution infusions had decreased insulin sensitivity over time. Glucose and insulin responses to endotoxemia differed between healthy horses and horses with EMS, with greater loss of glycemic control in EMS-affected horses. Horses with EMS also had greater derangements in glucose and insulin homeostasis that were potentially stress induced. It may therefore be helpful to avoid exposure of these horses to stressful situations.

Characterization of basal and lipopolysaccharide-induced microRNA expression in equine peripheral blood mononuclear cells using Next-Generation Sequencing

PubMed Central

Buechner-Maxwell, Virginia A.; Witonsky, Sharon G.; Pleasant, R. Scott; Werre, Stephen R.; Ahmed, S. Ansar

2017-01-01

The innate immune response to lipopolysaccharide contributes substantially to the morbidity and mortality of gram-negative sepsis. Horses and humans share an exquisite sensitivity to lipopolysaccharide and thus the horse may provide valuable comparative insights into this aspect of the inflammatory response. MicroRNAs, small non-coding RNA molecules acting as post-transcriptional regulators of gene expression, have key roles in toll-like receptor signaling regulation but have not been studied in this context in horses. The central hypothesis of this study was that lipopolysaccharide induces differential microRNA expression in equine peripheral blood mononuclear cells in a manner comparable to humans. Illumina Next Generation Sequencing was used to characterize the basal microRNA transcriptome in isolated peripheral blood mononuclear cells from healthy adult horses, and to evaluate LPS-induced changes in microRNA expression in cells cultured for up to four hours. Selected expression changes were validated using quantitative reverse-transcriptase PCR. Only miR-155 was significantly upregulated by LPS, changing in parallel with supernatant tumor necrosis factor-α concentration. Eight additional microRNAs, including miR-146a and miR-146b, showed significant expression change with time in culture without a clear LPS effect. Target predictions indicated a number of potential immunity-associated targets for miR-155 in the horse, including SOCS1, TAB2 and elements of the PI3K signaling pathway, suggesting that it is likely to influence the acute inflammatory response to LPS. Gene alignment showed extensive conservation of the miR-155 precursor gene and associated promoter regions between horses and humans. The basal and LPS-stimulated microRNA expression pattern characterized here were similar to those described in human leukocytes. As well as providing a resource for further research into the roles of microRNAs in immune responses in horses, this will facilitate inter

Modulation of lipopolysaccharide-induced chorioamnionitis in fetal sheep by maternal betamethasone.

PubMed

Wolfe, Katherine B; Snyder, Candice C; Gisslen, Tate; Kemp, Matthew W; Newnham, John P; Kramer, Boris W; Jobe, Alan H; Kallapur, Suhas

2013-12-01

We tested the hypothesis that the order of exposure to maternal betamethasone and intra-amniotic (IA) lipopolysaccharide (LPS) will differentially modulate inflammation in the chorioamnion. Time-mated Merino ewes with singleton fetuses received saline alone, IA LPS alone, maternal betamethasone before LPS, or betamethasone after LPS. We assessed inflammatory markers in the chorioamnion and the amniotic fluid. Inflammatory cell infiltration, expression of myeloperoxidase, serum amyloid A3 (acute phase reactant) in the chorioamnion, and levels of interleukin (IL)-8 in the amniotic fluid increased 7 days after LPS exposure. Betamethasone prior to LPS decreased infiltration of the inflammatory cells, CD3+ T cells, and decreased the levels of IL-1β and IL-8 in the amniotic fluid. Betamethasone 7 days prior to LPS exposure suppressed LPS-induced inflammation. The markers of inflammation largely had returned to the baseline 14 days after LPS exposure.

Paeonol attenuates lipopolysaccharide-induced depressive-like behavior in mice.

PubMed

Tao, Weiwei; Wang, Hanqing; Su, Qiang; Chen, Yanyan; Xue, Wenda; Xia, Baomei; Duan, Jinao; Chen, Gang

2016-04-30

The present study was designed to detect the anti-depressant effects of paeonol and the possible mechanisms in the lipopolysaccharide-induced depressive-like behavior. Open-field test(OFT), tail suspension test(TST) and forced swimming test(FST) were used to evaluate the behavioral activity. The contents of 5-hydroxytryptamine (5-HT) and norepinephrine (NE) in mice hippocampus were determined by HPLC-ECD. Serum interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α levels were evaluated by enzyme-linked immunosorbent assay (ELISA). Our results showed that LPS significantly decreased the levels of 5-HT and NE in the hippocampus. LPS also reduced open-field activity, as well as increased immobility duration in FST and TST. Paeonol administration could effectively reverse the alterations in the concentrations of 5-HT, NE and reduce the IL-6 and TNF-α levels. Moreover, paeonol effectively downregulated brain-derived neurotrophic factor (BDNF), tropomyosin-related kinase B (TrkB) and Nuclear factor-κB (NF-κB) in hippocampal. In conclusion, paeonol administration exhibited significant antidepressant-like effects in mice with LPS-induced depression. Copyright © 2016. Published by Elsevier Ireland Ltd.

Lipopolysaccharide interactions of C-terminal peptides from human thrombin.

PubMed

Singh, Shalini; Kalle, Martina; Papareddy, Praveen; Schmidtchen, Artur; Malmsten, Martin

2013-05-13

Interactions with bacterial lipopolysaccharide (LPS), both in aqueous solution and in lipid membranes, were investigated for a series of amphiphilic peptides derived from the C-terminal region of human thrombin, using ellipsometry, dual polarization interferometry, fluorescence spectroscopy, circular dichroism (CD), dynamic light scattering, and z-potential measurements. The ability of these peptides to block endotoxic effects caused by LPS, monitored through NO production in macrophages, was compared to peptide binding to LPS and its endotoxic component lipid A, and to size, charge, and secondary structure of peptide/LPS complexes. While the antiendotoxic peptide GKY25 (GKYGFYTHVFRLKKWIQKVIDQFGE) displayed significant binding to both LPS and lipid A, so did two control peptides with either selected D-amino acid substitutions or with maintained composition but scrambled sequence, both displaying strongly attenuated antiendotoxic effects. Hence, the extent of LPS or lipid A binding is not the sole discriminant for the antiendotoxic effect of these peptides. In contrast, helix formation in peptide/LPS complexes correlates to the antiendotoxic effect of these peptides and is potentially linked to this functionality. Preferential binding to LPS over lipid membrane was furthermore demonstrated for these peptides and preferential binding to the lipid A moiety within LPS inferred.

Curcumin Attenuation of Lipopolysaccharide Induced Cardiac Hypertrophy in Rodents

PubMed Central

Graham, Thomas; Reddy, Gopal

2013-01-01

To study the ameliorating effects of curcumin in lipopolysaccharide (LPS) induced cardiac hypertrophy, mice were assigned to 4 groups (3 males and 3 females in each group): (A) control, (B) curcumin: 100 μg/kg of body weight by intraperitoneal route (IP), (C) LPS: 60 mg/kg (IP), and (D) LPS + curcumin: both at previously stated concentrations by IP route. All mice were sacrificed as 12 hr and 24 hrs groups accordingly after LPS injection. The hearts were collected, photographed for cardiomegaly, and weighed to compare heart weight/brain weight (HW/BW) in mg/mg. For immunohistochemistry, the tissue sections were exposed to histone H3, H4 and acetylated histone H3, H4 antibody. LPS induced a significant increase in histone acetylation as shown by intense staining. In curcumin + LPS treated mice nuclear staining was similar to the control group indicating that curcumin traversed the histone acetylation activity of the LPS. To further check the mechanism of action of curcumin, p300 protein acetylation levels were analyzed. This study suggests that the probable mechanism of action of curcumin is via the reduction of p300 HAT activity. PMID:24236240

Involvement of cannabinoids in the cardioprotection induced by lipopolysaccharide

PubMed Central

Lagneux, Caroline; Lamontagne, Daniel

2001-01-01

We have examined the involvement of the endocannabinoid system in the cardioprotection triggered by lipopolysaccharide (LPS). Rats were treated with saline or LPS (10 μg Kg−1). 24 h later, hearts were excised, retrogradely perfused, submitted to a low-flow ischaemia (0.6 ml min−1) for 90 min and reperfused for 60 min. Some hearts were perfused with either SR 141716A (a cannabinoid CB1, receptor antagonist 1 μM), SR 144528 (a CB2 receptor anagonist μM), NNLA (3 μM) or sodium nitroprusside (1 μM) 5 min before ischaemia and during the ischaemic period. The cardioprotective effects of LPS treatment, in terms of infarction and functional recovery, were not altered by the perfusion of SR 141716A but abolished by both SR 144528 and NNLA. Finally, SR 144528 abolished the beneficial effects of SNP perfusion. Our results suggest an involvement of endocannabinoids, acting through the CB2 receptors, in the cardioprotection triggered by LPS against myocardial ischaemia. This could be attributed to a relationship between cannabinoids and NO. PMID:11181418

The Alternaria alternata Mycotoxin Alternariol Suppresses Lipopolysaccharide-Induced Inflammation

PubMed Central

Grover, Shivani; Lawrence, Christopher B.

2017-01-01

The Alternaria mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) have been shown to possess genotoxic and cytotoxic properties. In this study, the ability of AOH and AME to modulate innate immunity in the human bronchial epithelial cell line (BEAS-2B) and mouse macrophage cell line (RAW264.7) were investigated. During these studies, it was discovered that AOH and to a lesser extent AME potently suppressed lipopolysaccharide (LPS)-induced innate immune responses in a dose-dependent manner. Treatment of BEAS-2B cells with AOH resulted in morphological changes including a detached pattern of growth as well as elongated arms. AOH/AME-related immune suppression and morphological changes were linked to the ability of these mycotoxins to cause cell cycle arrest at the G2/M phase. This model was also used to investigate the AOH/AME mechanism of immune suppression in relation to aryl hydrocarbon receptor (AhR). AhR was not found to be important for the immunosuppressive properties of AOH/AME, but appeared important for the low levels of cell death observed in BEAS-2B cells. PMID:28726766

Studies on a lipopolysaccharide-protein complex from Yersinia pseudotuberculosis. 1 isolation and characterization.

PubMed

Solov'eva, T F; Yermak, I M; Bondarenko, O D; Frolova, G M; Ovodov, Y S

1979-01-01

A comparative study of various procedures of a lipopolysaccharide-protein complex (LPPC) from Yersinia pseudotuberculosis was carried out. The materials obtained were fractionated by molecular-sieve chromatography on Sepharose 2B resulting in highly aggregated complexes with antigen activity. LPPC aggregates dissociated in the presence of sodium dodecylsulphate (SDS) and urea. The chemical composition and serologic properties of fractions obtained are under consideration. The protein component of the complex consists of two major polypeptides (molecular weights--45,000 and 20,000) and some minor ones. The LPS component appeared to give 2--3 narrow bands in gel under conditions of SDS-polyacrylamide gel electrophoresis. It is suggested that such fractionation is caused by LPS association-dissociation in the course of electrophoresis.

Distribution of flunixin residues in muscles of dairy cattle dosed with lipopolysaccharide or saline and treated with flunixin by intravenous or intramuscular injection

USDA-ARS?s Scientific Manuscript database

Twenty dairy cows received flunixin meglumine at 2.2 mg/kg bw, administered once daily by either the intravenous (IV) or intra muscular (IM) route for three consecutive days with either intravenous normal saline (NS) or lipopolysaccharide (LPS) providing a balanced design with five animals per group...

New Amphiphilic Neamine Derivatives Active against Resistant Pseudomonas aeruginosa and Their Interactions with Lipopolysaccharides

PubMed Central

Sautrey, Guillaume; Zimmermann, Louis; Deleu, Magali; Delbar, Alicia; Souza Machado, Luiza; Jeannot, Katy; Van Bambeke, Françoise; Buyck, Julien M.; Decout, Jean-Luc

2014-01-01

The development of novel antimicrobial agents is urgently required to curb the widespread emergence of multidrug-resistant bacteria like colistin-resistant Pseudomonas aeruginosa. We previously synthesized a series of amphiphilic neamine derivatives active against bacterial membranes, among which 3′,6-di-O-[(2″-naphthyl)propyl]neamine (3′,6-di2NP), 3′,6-di-O-[(2″-naphthyl)butyl]neamine (3′,6-di2NB), and 3′,6-di-O-nonylneamine (3′,6-diNn) showed high levels of activity and low levels of cytotoxicity (L. Zimmermann et al., J. Med. Chem. 56:7691–7705, 2013). We have now further characterized the activity of these derivatives against colistin-resistant P. aeruginosa and studied their mode of action; specifically, we characterized their ability to interact with lipopolysaccharide (LPS) and to alter the bacterial outer membrane (OM). The three amphiphilic neamine derivatives were active against clinical colistin-resistant strains (MICs, about 2 to 8 μg/ml), The most active one (3′,6-diNn) was bactericidal at its MIC and inhibited biofilm formation at 2-fold its MIC. They cooperatively bound to LPSs, increasing the outer membrane permeability. Grafting long and linear alkyl chains (nonyl) optimized binding to LPS and outer membrane permeabilization. The effects of amphiphilic neamine derivatives on LPS micelles suggest changes in the cross-bridging of lipopolysaccharides and disordering in the hydrophobic core of the micelles. The molecular shape of the 3′,6-dialkyl neamine derivatives induced by the nature of the grafted hydrophobic moieties (naphthylalkyl instead of alkyl) and the flexibility of the hydrophobic moiety are critical for their fluidifying effect and their ability to displace cations bridging LPS. Results from this work could be exploited for the development of new amphiphilic neamine derivatives active against colistin-resistant P. aeruginosa. PMID:24867965

Pharmacologic studies on ET-26 hydrochloride in a rat model of lipopolysaccharide-induced sepsis.

PubMed

Wang, Bin; Jiang, Junli; Yang, Jun; Chen, Jun; Zhu, Zhaoqiong; Liu, Jin; Zhang, Wensheng

2017-11-15

ET-26 hydrochloride (ET-26 HCl) is a promising sedation-hypnotic compound with stable hemodynamic features that elicits virtually no adrenocortical suppression. However, whether it preserves better pharmacologic characteristics in a rat model of sepsis is not known. This study compared the survival rate, levels of corticosterone and pro-inflammatory cytokines, and histologic injury in the lungs and kidneys of rats suffering from sepsis treated with ET-26 HCl, etomidate, or normal saline (NS). Rats were given lipopolysaccharide (1mg/kg body weight, i.v.) to establish a sepsis model. Thirty minutes after lipopolysaccharide administration, ET-26 HCl, etomidate or NS were given as a bolus injection at equivalent doses. Plasma levels of corticosterone, interleukin-1β, interleukin-6, interleukin-10, and tumor necrosis factor-α were measured 1, 2, 4, 6 and 24h after administration. Histologic injury was observed at the time of death or 24h after drug administration. The survival rate for rats in the etomidate, ET-26 HCl and NS groups was 40%, 90% and 90%, respectively. Corticosterone concentrations in the etomidate group were lower than those in the other groups 1h after administration of hypnotic compounds. Concentrations of pro-inflammatory cytokines in the ET-26 HCl group and NS group were not significantly different, but were significantly lower than those in the etomidate group. The injury scores of kidneys and lungs in the etomidate group were higher than those in ET-26 HCl and NS groups. ET-26 HCl showed virtually no suppression of corticosterone synthesis, lower concentrations of pro-inflammatory cytokines, higher survival rate, and less organ injury in rats suffering from sepsis compared with the etomidate group. It may be safer to induce anesthesia using ET-26 HCl, rather than etomidate, in patients suffering from sepsis. Copyright © 2017 Elsevier B.V. All rights reserved.

THE EMBRYOLETHALITY OF LIPOPOLYSACCHARIDE IN CD-1 AND METALLOTHIONEIN I-II NULL MICE: LACK OF A ROLE FOR INDUCED ZINC DEFICIENCY OR METALLOTHIONEIN INDUCTION

EPA Science Inventory

ABSTRACT

Lipopolysaccharide (LPS) is embryolethal in CD-1 mice. LPS induces metallothionein (MT) via cytokines, including TNF-, IL-1 and IL-6, which initiate and maintain the acute phase response. Maternal hepatic MT induction in pregnant rats, by diverse toxicants, can ...

Visualization and analysis of lipopolysaccharide distribution in binary phospholipid bilayers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henning, Maria Florencia; Sanchez, Susana; Bakas, Laura, E-mail: lbakas@biol.unlp.edu.ar

2009-05-22

Lipopolysaccharide (LPS) is an endotoxin released from the outer membrane of Gram-negative bacteria during infections. It have been reported that LPS may play a role in the outer membrane of bacteria similar to that of cholesterol in eukaryotic plasma membranes. In this article we compare the effect of introducing LPS or cholesterol in liposomes made of dipalmitoylphosphatidylcholine/dioleoylphosphatidylcholine on the solubilization process by Triton X-100. The results show that liposomes containing LPS or cholesterol are more resistant to solubilization by Triton X-100 than the binary phospholipid mixtures at 4 {sup o}C. The LPS distribution was analyzed on GUVs of DPPC:DOPC usingmore » FITC-LPS. Solid and liquid-crystalline domains were visualized labeling the GUVs with LAURDAN and GP images were acquired using a two-photon microscope. The images show a selective distribution of LPS in gel domains. Our results support the hypothesis that LPS could aggregate and concentrate selectively in biological membranes providing a mechanism to bring together several components of the LPS-sensing machinery.« less

Modulation of lipopolysaccharide-induced chorioamnionitis by Ureaplasma parvum in sheep.

PubMed

Snyder, Candice C; Wolfe, Katherine B; Gisslen, Tate; Knox, Christine L; Kemp, Matthew W; Kramer, Boris W; Newnham, John P; Jobe, Alan H; Kallapur, Suhas G

2013-05-01

Ureaplasma colonization in the setting of polymicrobial flora is common in women with chorioamnionitis, and is a risk factor for preterm delivery and neonatal morbidity. We hypothesized that Ureaplasma colonization of amniotic fluid would modulate chorioamnionitis induced by Escherichia coli lipopolysaccharide (LPS). Sheep received intraamniotic (IA) injections of media (control) or live Ureaplasma either 7 or 70 days before delivery. Another group received IA LPS 2 days before delivery. To test for interactions, U parvum-exposed animals were challenged with IA LPS, and delivered 2 days later. All animals were delivered preterm at 125 ± 1 day of gestation. Both IA Ureaplasma and LPS induced leukocyte infiltration of chorioamnion. LPS greatly increased the expression of proinflammatory cytokines and myeloperoxidase in leukocytes, while Ureaplasma alone caused modest responses. Interestingly, 7-day but not 70-day Ureaplasma exposure significantly down-regulated LPS-induced proinflammatory cytokines and myeloperoxidase expression in the chorioamnion. Acute (7-day) U parvum exposure can suppress LPS-induced chorioamnionitis. Copyright © 2013 Mosby, Inc. All rights reserved.

Chlorogenic acid protects mice against lipopolysaccharide-induced acute lung injury.

PubMed

Zhang, Xu; Huang, Huang; Yang, Tingting; Ye, Yin; Shan, Jianhua; Yin, Zhimin; Luo, Lan

2010-07-01

Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in human diet. Our previous in vitro study demonstrates that CGA presents anti-inflammatory activities in RAW 264.7 cells. Here we show that CGA protects mice against lipopolysaccharide (LPS)-induced acute lung injury (ALI). We treated mice with CGA (5, 20 and 50 mg/kg body weight) 30 min or 3 h after intratracheal administration of LPS. The histological results showed that CGA, at dose of 50 mg/kg, protected mice from LPS-induced ALI which displayed by edema, haemorrhage, blood vessel and alveolar structural damage. CGA inhibited LPS-increased pulmonary MPO activity and migration of polymorphonuclear neutrophils (PMNs) into bronchoalveolar lavage fluid (BALF). Furthermore, CGA markedly decreased the activity of inducible nitric oxide synthase (iNOS) in lung tissues and thus prevented nitric oxide (NO) release in response to LPS challenge. In conclusion, these results indicated that CGA was greatly effective in inhibiting ALI and might act as a potential therapeutic reagent for treating ALI in the future. 2010 Elsevier Ltd. All rights reserved.

Effect of Kramecyne on the Inflammatory Response in Lipopolysaccharide-Stimulated Peritoneal Macrophages

PubMed Central

Sánchez-Miranda, E.; Lemus-Bautista, J.; Pérez, S.; Pérez-Ramos, J.

2013-01-01

Kramecyne is a new peroxide, it was isolated from Krameria cytisoides, methanol extract, and this plant was mostly found in North and South America. This compound showed potent anti-inflammatory activity; however, the mechanisms by which this compound exerts its anti-inflammatory effect are not well understood. In this study, we examined the effects of kramecyne on inflammatory responses in mouse lipopolysaccharide- (LPS-) induced peritoneal macrophages. Our findings indicate that kramecyne inhibits LPS-induced production of tumor necrosis factor (TNF-α) and interleukin- (IL-) 6. During the inflammatory process, levels of cyclooxygenase- (COX-) 2, nitric oxide synthase (iNOS), and nitric oxide (NO) increased in mouse peritoneal macrophages; however, kramecyne suppressed them significantly. These results provide novel insights into the anti-inflammatory actions and support its potential use in the treatment of inflammatory diseases. PMID:23573152

Structure of the polysaccharides from the lipopolysaccharide of Azospirillum brasilense Jm125A2.

PubMed

Sigida, Elena N; Fedonenko, Yuliya P; Shashkov, Alexander S; Zdorovenko, Evelina L; Konnova, Svetlana A; Ignatov, Vladimir V; Knirel, Yuriy A

2015-10-30

Two polysaccharides were obtained by mild acid degradation of the lipopolysaccharide of associative nitrogen-fixing bacteria Azospirillum brasilense Jm125A2 isolated from the rhizosphere of a pearl millet. The following structures of the polysaccharides were established by sugar and methylation analyses, Smith degradation, and (1)H and (13)C NMR spectroscopy: [Formula: see text] Structure 1 has been reported earlier for a polysaccharide from A. brasilense S17 (Fedonenko YP, Konnova ON, Zdorovenko EL, Konnova SA, Zatonsky GV, Shaskov AS, Ignatov VV, Knirel YA. Carbohydr Res 2008;343:810-6), whereas to our knowledge structure 2 has not been hitherto found in bacterial polysaccharides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microglial ablation and lipopolysaccharide preconditioning affects pilocarpine-induced seizures in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mirrione, M.M.; Mirrione, M.M.; Konomosa, D.K.

2010-04-01

Activated microglia have been associated with neurodegeneration in patients and in animal models of Temporal Lobe Epilepsy (TLE), however their precise functions as neurotoxic or neuroprotective is a topic of significant investigation. To explore this, we examined the effects of pilocarpine-induced seizures in transgenic mice where microglia/macrophages were conditionally ablated. We found that unilateral ablation of microglia from the dorsal hippocampus did not alter acute seizure sensitivity. However, when this procedure was coupled with lipopolysaccharide (LPS) preconditioning (1 mg/kg given 24 h prior to acute seizure), we observed a significant pro-convulsant phenomenon. This effect was associated with lower metabolic activationmore » in the ipsilateral hippocampus during acute seizures, and could be attributed to activity in the mossy fiber pathway. These findings reveal that preconditioning with LPS 24 h prior to seizure induction may have a protective effect which is abolished by unilateral hippocampal microglia/macrophage ablation.« less

Adaptive Redox Response of Mesenchymal Stromal Cells to Stimulation with Lipopolysaccharide Inflammagen: Mechanisms of Remodeling of Tissue Barriers in Sepsis

DTIC Science & Technology

2013-03-08

Mechanisms of Remodeling of Tissue Barriers in Sepsis Nikolai V. Gorbunov1*, Bradley R. Garrison1, Dennis P. McDaniel2, Min Zhai1, Pei-Jyun Liao1...Adaptive Redox Response of Mesenchymal Stromal Cells to Stimulation with Lipopolysaccharide Inflammagen: Mechanisms of Remodeling of Tissue Barriers... mechanisms driving homeostatic responses of defense barriers to infections. This report presents results of in vitro investigations of the redox

Salmonella enterica Serovar Typhi Lipopolysaccharide O-Antigen Modification Impact on Serum Resistance and Antibody Recognition

DOE PAGES

Kintz, Erica; Heiss, Christian; Black, Ian; ...

2017-02-06

Salmonella enterica serovar Typhi is a human-restricted Gram-negative bacterial pathogen responsible for causing an estimated 27 million cases of typhoid fever annually, leading to 217,000 deaths, and current vaccines do not offer full protection. The O-antigen side chain of the lipopolysaccharide is an immunodominant antigen, can define host-pathogen interactions, and is under consideration as a vaccine target for some Gram-negative species. The composition of the O-antigen can be modified by the activity of glycosyltransferase (gtr) operons acquired by horizontal gene transfer. Here we investigate the role of two gtr operons that we identified in the S. Typhi genome. Strains weremore » engineered to express specific gtr operons. Full chemical analysis of the O-antigens of these strains identified gtr-dependent glucosylation and acetylation. The glucosylated form of the O-antigen mediated enhanced survival in human serum and decreased complement binding. A single nucleotide deviation from an epigenetic phase variation signature sequence rendered the expression of this glucosylating gtr operon uniform in the population. In contrast, the expression of the acetylating gtrC gene is controlled by epigenetic phase variation. Acetylation did not affect serum survival, but phase variation can be an immune evasion mechanism, and thus, this modification may contribute to persistence in a host. In murine immunization studies, both O-antigen modifications were generally immunodominant. Our results emphasize that natural O-antigen modifications should be taken into consideration when assessing responses to vaccines, especially O-antigen-based vaccines, and that the Salmonella gtr repertoire may confound the protective efficacy of broad-ranging Salmonella lipopolysaccharide conjugate vaccines.« less

Salmonella enterica Serovar Typhi Lipopolysaccharide O-Antigen Modification Impact on Serum Resistance and Antibody Recognition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kintz, Erica; Heiss, Christian; Black, Ian

Salmonella enterica serovar Typhi is a human-restricted Gram-negative bacterial pathogen responsible for causing an estimated 27 million cases of typhoid fever annually, leading to 217,000 deaths, and current vaccines do not offer full protection. The O-antigen side chain of the lipopolysaccharide is an immunodominant antigen, can define host-pathogen interactions, and is under consideration as a vaccine target for some Gram-negative species. The composition of the O-antigen can be modified by the activity of glycosyltransferase (gtr) operons acquired by horizontal gene transfer. Here we investigate the role of two gtr operons that we identified in the S. Typhi genome. Strains weremore » engineered to express specific gtr operons. Full chemical analysis of the O-antigens of these strains identified gtr-dependent glucosylation and acetylation. The glucosylated form of the O-antigen mediated enhanced survival in human serum and decreased complement binding. A single nucleotide deviation from an epigenetic phase variation signature sequence rendered the expression of this glucosylating gtr operon uniform in the population. In contrast, the expression of the acetylating gtrC gene is controlled by epigenetic phase variation. Acetylation did not affect serum survival, but phase variation can be an immune evasion mechanism, and thus, this modification may contribute to persistence in a host. In murine immunization studies, both O-antigen modifications were generally immunodominant. Our results emphasize that natural O-antigen modifications should be taken into consideration when assessing responses to vaccines, especially O-antigen-based vaccines, and that the Salmonella gtr repertoire may confound the protective efficacy of broad-ranging Salmonella lipopolysaccharide conjugate vaccines.« less

Toll-like receptor 4 mediates lipopolysaccharide-induced muscle catabolism via coordinate activation of ubiquitin-proteasome and autophagy-lysosome pathways

PubMed Central

Doyle, Alexander; Zhang, Guohua; Abdel Fattah, Elmoataz A.; Eissa, N. Tony; Li, Yi-Ping

2011-01-01

Cachectic muscle wasting is a frequent complication of many inflammatory conditions, due primarily to excessive muscle catabolism. However, the pathogenesis and intervention strategies against it remain to be established. Here, we tested the hypothesis that Toll-like receptor 4 (TLR4) is a master regulator of inflammatory muscle catabolism. We demonstrate that TLR4 activation by lipopolysaccharide (LPS) induces C2C12 myotube atrophy via up-regulating autophagosome formation and the expression of ubiquitin ligase atrogin-1/MAFbx and MuRF1. TLR4-mediated activation of p38 MAPK is necessary and sufficient for the up-regulation of atrogin1/MAFbx and autophagosomes, resulting in myotube atrophy. Similarly, LPS up-regulates muscle autophagosome formation and ubiquitin ligase expression in mice. Importantly, autophagy inhibitor 3-methyladenine completely abolishes LPS-induced muscle proteolysis, while proteasome inhibitor lactacystin partially blocks it. Furthermore, TLR4 knockout or p38 MAPK inhibition abolishes LPS-induced muscle proteolysis. Thus, TLR4 mediates LPS-induced muscle catabolism via coordinate activation of the ubiquitin-proteasome and the autophagy-lysosomal pathways.—Doyle, A., Zhang, G., Abdel Fattah, E. A., Eissa, N. T., Li, Y.-P. Toll-like receptor 4 mediates lipopolysaccharide-induced muscle catabolism via coordinate activation of ubiquitin-proteasome and autophagy-lysosome pathways. PMID:20826541

Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation

PubMed Central

Reisenauer, Chris J.; Bhatt, Dhaval P.; Mitteness, Dane J.; Slanczka, Evan R.; Gienger, Heidi M.; Watt, John A.; Rosenberger, Thad A.

2011-01-01

Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6g/kg by oral gavage. In parallel experiments free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 hr. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 hr. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive GFAP-positive astrocytes and activated CD11b-positive microglia by 40–50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of ChAT-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. PMID:21272004

Hepatoprotective activity of Tridax procumbens against d-galactosamine/lipopolysaccharide-induced hepatitis in rats.

PubMed

Ravikumar, Vilwanathan; Shivashangari, Kanchi Subramanian; Devaki, Thiruvengadam

2005-10-03

The hepatoprotective activity of aerial parts of Tridax procumbens was investigated against d-Galactosamine/Lipopolysaccharide (d-GalN/LPS) induced hepatitis in rats. d-GalN/LPS (300 mg/kg body weight/30 microg/kg body weight)-induced hepatic damage was manifested by a significant increase in the activities of marker enzymes (aspartate transaminase, alanine transaminase, alkaline phosphatase, lactate dehydrogenase and gamma glutamyl transferase) and bilirubin level in serum and lipids both in serum and liver. Pretreatment of rats with a chloroform insoluble fraction from ethanolic extract of Tridax procumbens reversed these altered parameters to normal values. The biochemical observations were supplemented by histopathological examination of liver sections. Results of this study revealed that Tridax procumbens could afford a significant protection in the alleviation of d-GalN/LPS-induced hepatocellular injury.

Dose-Dependent Effects of Multispecies Probiotic Supplementation on the Lipopolysaccharide (LPS) Level and Cardiometabolic Profile in Obese Postmenopausal Women: A 12-Week Randomized Clinical Trial.

PubMed

Szulińska, Monika; Łoniewski, Igor; van Hemert, Saskia; Sobieska, Magdalena; Bogdański, Paweł

2018-06-15

During the postmenopausal period, the risk of cardiovascular diseases is increased in many obese women and is associated with a worse cardiometabolic profile and a sub-chronic low-grade systemic inflammation caused by a gut barrier permeability dysfunction. Here, we tested whether administration of two different dosages of the multispecies probiotic Ecologic ® Barrier influenced the cardiometabolic biochemical parameters and lipopolysaccharide levels, the latter used as a marker of increased gut permeability in obese postmenopausal women. A total of 81 obese Caucasian postmenopausal women participated in the trial. The subjects were randomly assigned to three groups that received a placebo, a low dose (LD) (2.5 × 10⁸ colony forming units (CFU) per day), or a high dose (HD) (1 × 10 10 CFU per day) of lyophilisate powder containing live multispecies probiotic bacteria. The probiotic supplement was administered each day in two equal portions for 12 weeks. We found significant ( p < 0.05) favorable changes (mostly large or medium effects) in the evaluated parameters in both the HD and LD groups but not in the placebo group. In the HD group, lipopolysaccharide, waist, fat mass, subcutaneous fat, uric acid, total cholesterol, triglycerides, low-density lipoprotein cholesterol, glucose, insulin, and insulin-resistant index (HOMA-IR) were improved. Similar changes were observed in the LD group, except for lipopolysaccharide, uric acid, triglycerides, and glucose levels. Additionally, significant differences were observed in both groups in terms of fat percentage and visceral fat. When the mean changes were compared between the three groups, statistically significant differences in lipopolysaccharide levels, uric acid, glucose, insulin, and HOMA-IR were found. Post hoc tests revealed significant differences in the mean changes (mostly medium effects) between the HD and LD groups for uric acid, glucose, insulin, and HOMA-IR. In the 12-week randomized

Polymethoxy flavonoids, nobiletin and tangeretin, prevent lipopolysaccharide-induced inflammatory bone loss in an experimental model for periodontitis.

PubMed

Tominari, Tsukasa; Hirata, Michiko; Matsumoto, Chiho; Inada, Masaki; Miyaura, Chisato

2012-01-01

Nobiletin, a polymethoxy flavonoid (PMF), inhibits systemic bone resorption and maintains bone mass in estrogen-deficient ovariectomized mice. This study examined the anti-inflammatory effects of PMFs, nobiletin, and tangeretin on lipopolysaccharide (LPS)-induced bone resorption. Nobiletin and tangeretin suppressed LPS-induced osteoclast formation and bone resorption and suppressed the receptor activator of NFκB ligand-induced osteoclastogenesis in RAW264.7 macrophages. Nobiletin clearly restored the alveolar bone mass in a mouse experimental model for periodontitis by inhibiting LPS-induced bone resorption. PMFs may therefore provide a new therapeutic approach for periodontal bone loss.

DNA polymorphism analysis of Brucella lipopolysaccharide genes reveals marked differences in O-polysaccharide biosynthetic genes between smooth and rough Brucella species and novel species-specific markers

PubMed Central

2009-01-01

Background The lipopolysaccharide is a major antigen and virulence factor of Brucella, an important bacterial pathogen. In smooth brucellae, lipopolysaccharide is made of lipid A-core oligosaccharide and N-formylperosamine O-polysaccharide. B. ovis and B. canis (rough species) lack the O-polysaccharide. Results The polymorphism of O-polysaccharide genes wbkE, manAO-Ag, manBO-Ag, manCO-Ag, wbkF and wbkD) and wbo (wboA and wboB), and core genes manBcore and wa** was analyzed. Although most genes were highly conserved, species- and biovar-specific restriction patterns were found. There were no significant differences in putative N-formylperosamyl transferase genes, suggesting that Brucella A and M serotypes are not related to specific genes. In B. pinnipedialis and B. ceti (both smooth), manBO-Ag carried an IS711, confirming its dispensability for perosamine synthesis. Significant differences between smooth and rough species were found in wbkF and wbkD, two adjacent genes putatively related to bactoprenol priming for O-polysaccharide polymerization. B. ovis wbkF carried a frame-shift and B. canis had a long deletion partially encompassing both genes. In smooth brucellae, this region contains two direct repeats suggesting the deletion mechanism. Conclusion The results define species and biovar markers, confirm the dispensability of manBO-Ag for O-polysaccharide synthesis and contribute to explain the lipopolysaccharide structure of rough and smooth Brucella species. PMID:19439075

Lipopolysaccharide stimulates HepG2 human hepatoma cells in the presence of lipopolysaccharide-binding protein via CD14.

PubMed

Nanbo, A; Nishimura, H; Muta, T; Nagasawa, S

1999-02-01

Lipopolysaccharide (LPS)-binding protein (LBP), an opsonin for activation of macrophages by bacterial LPS, is synthesized in hepatocytes and is known to be an acute phase protein. Recently, cytokine-induced production of LBP was reported to increase 10-fold in hepatocytes isolated from LPS-treated rats, compared with those from normal rats. However, the mechanism by which the LPS treatment enhances the effect of cytokines remains to be clarified. In the present study, we examined whether LPS alone or an LPS/LBP complex directly stimulates the hepatocytes, leading to acceleration of the cytokine-induced LBP production. HepG2 cells (a human hepatoma cell line) were shown to express CD14, a glycosylphosphatidylinositol-anchored LPS receptor, by both RT/PCR and flow cytometric analyses. An LPS/LBP complex was an effective stimulator for LBP and CD14 production in HepG2 cells, but stimulation of the cells with either LPS or LBP alone did not significantly accelerate the production of these proteins. The findings were confirmed by semiquantitative RT/PCR analysis of mRNA levels of LBP and CD14 in HepG2 cells after stimulation with LPS alone and an LPS/LBP complex. In addition, two monoclonal antibodies (mAbs) to CD14 (3C10 and MEM-18) inhibited LPS/LBP-induced cellular responses of HepG2 cells. Furthermore, prestimulation of HepG2 cells with LPS/LBP augmented cytokine-induced production and gene expression of LBP and CD14. All these findings suggest that an LPS/LBP complex, but not free LPS, stimulates HepG2 cells via CD14 leading to increased basal and cytokine-induced LBP and CD14 production.

Annexin A5 binds to lipopolysaccharide and reduces its endotoxin activity.

PubMed

Rand, Jacob H; Wu, Xiao-Xuan; Lin, Elaine Y; Griffel, Alexander; Gialanella, Philip; McKitrick, John C

2012-01-01

Annexin A5 (AnxA5) has a high affinity for phosphatidylserine. The protein is widely used to detect apoptotic cells because phosphatidylserine, a phospholipid that is normally present in the inner leaflets of cytoplasmic membranes, becomes translocated to the outer leaflets during programmed cell death. Here we report the novel observation that AnxA5 binds to Gram-negative bacteria via the lipid A domain of lipopolysaccharide (LPS). Binding of AnxA5 to bacteria was measured quantitatively, confirmed by fluorescence microscopy, and found to be inhibited by antibodies against lipid A. AnxA5 also bound to purified dot-blotted LPS and lipid A. Through ellipsometry, we found that the binding of AnxA5 to purified LPS was calcium dependent and rapid and showed a high affinity-characteristics similar to those of AnxA5 binding to phosphatidylserine. Initial functional studies indicated that AnxA5 can affect LPS activities. AnxA5 inhibited LPS-mediated gelation in the Limulus amebocyte lysate assay. Incubation of LPS with the protein reduced the quantity of tumor necrosis factor alpha (TNF-α) released by cultured monocytes compared to that released upon incubation with LPS alone. Initial in vivo experiments indicated that injection of mice with LPS preincubated with AnxA5 produced serum TNF-α levels lower than those seen after injection of LPS alone. These data demonstrate that AnxA5 binds to LPS and open paths to investigation of the potential biological and therapeutic implications of this interaction. AnxA5 is highly expressed in cells that have a barrier function-including, among others, vascular endothelium, placental trophoblasts, and epithelial cells lining bile ducts, renal tubules, mammary ducts, and nasal epithelium. The protein has been well characterized for its binding to phospholipid bilayers that contain phosphatidylserine. This report of a previously unrecognized activity of AnxA5 opens the door to investigation of the possibility that this binding may have

The effect of lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response as assessed by luminol-amplified chemiluminescence in dairy cows

USDA-ARS?s Scientific Manuscript database

The differences between lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) on whole blood oxidative response using luminol-amplified chemiluminescence (CL) are currently unknown in cattle. Luminol-dependent CL measures the amount of reactive oxygen species released from leukocytes a...

Evening primrose oil or forskolin ameliorates celecoxib-enhanced upregulation of tissue factor expression in mice subjected to lipopolysaccharide-induced endotoxemia.

PubMed

Mosaad, Sarah M; Zaitone, Sawsan A; Ahmed, Amal A M; Abo-Elmatty, Dina M; El-Baz, Amani A; Moustafa, Yasser M

2017-05-01

Celecoxib, a selective cyclooxygenase-2 inhibitor, produces thrombotic events in patients predisposed to cardiovascular risk factors. One theory reported an increase in endothelial expression of tissue factor (TF) as a predisposing factor. This work explored the effect of evening primrose oil (EPO), a source of prostaglandin E1, and forskolin (a cyclic adenosine monophosphate stimulator) against the prothrombotic effect of celecoxib in mice. Lipopolysaccharide mouse model of endotoxemia was used to induce an upregulation of TF activity. Male mice received celecoxib (25 mg/kg), celecoxib plus EPO, or celecoxib plus forskolin for 4 weeks and then subjected to a prothrombotic challenge in the form of an intraperitoneal injection of lipopolysaccharide. Results showed an increase in plasma TF activity, endothelial TF expression, and thrombin-antithrombin (TAT) but lower antithrombin III (ATIII) level in mice that received celecoxib in comparison to those that received the vehicle. Adding EPO or forskolin to celecoxib regimen significantly decreased the prothrombotic effect of celecoxib. A positive correlation (r = 0.8501) was found between TF activity and TAT. Co-administration of EPO or forskolin decreased the activity of TF and mitigated the prothrombotic effect of celecoxib. Therefore, these combinations may have the utility to abrogate the prothrombotic adverse effect of celecoxib in clinical setting.

Patterns of B-lymphocyte gene expression elicited by lipopolysaccharide mitogen.

PubMed Central

Janossy, G; Snajdr, J; Simak-Ellis, M

1976-01-01

When large proportions of B lymphocytes from the murine spleen are stimulated in vitro by bacterial lipopolysaccharide (LPS) B lymphoblasts with small amounts of intracellular immunoglobulin (Ig) and plasmablasts with large amounts of intracellular Ig concomitantly proliferate. It is likely that B lymphocytes are heterogeneous and LPS activates B cells to express their predetermined functional capacity since bromodeoxyuridine does not inhibit the initiation of Ig synthesis in plasmablasts, and Ig synthesis starts before these cells complete their first mitosis. The results suggest that LPS is a potent polyclonal activator (of a B-cell subset) but it is not a differentiation factor in the sense that it is unable to determine whether its target cell develops extensive endoplasmic reticulum or follows a different pathway. The results do not exclude that modulation of B cells' genetic programming might take place during T cell-dependent B-lymphocyte activation. The observed B-cell heterogeneity offers a possible explanation for the concomitant emergence of B memory cells and antibody producers during the early phase of immune responses in vivo. Images Figure 3 Figure 5 Figure 7 Figure 8 PMID:1088414

Structure-activity relationships of lipopolysaccharide sequestration in guanylhydrazone-bearing lipopolyamines.

PubMed

Wu, Wenyan; Sil, Diptesh; Szostak, Michal L; Malladi, Subbalakshmi S; Warshakoon, Hemamali J; Kimbrell, Matthew R; Cromer, Jens R; David, Sunil A

2009-01-15

The toxicity of gram-negative bacterial endotoxin (lipopolysaccharide, LPS) resides in its structurally highly conserved glycolipid component called lipid A. Our major goal has been to develop small-molecules that would sequester LPS by binding to the lipid A moiety, so that it could be useful for the prophylaxis or adjunctive therapy of gram-negative sepsis. We had previously identified in rapid-throughput screens several guanylhydrazones as potent LPS binders. We were desirous of examining if the presence of the guanylhydrazone (rather than an amine) functionality would afford greater LPS sequestration potency. In evaluating a congeneric set of guanylhydrazone analogues, we find that C(16) alkyl substitution is optimal in the N-alkylguanylhydrazone series; a homospermine analogue with the terminal amine N-alkylated with a C(16) chain with the other terminus of the molecule bearing an unsubstituted guanylhydrazone moiety is marginally more active, suggesting very slight, if any, steric effects. Neither C(16) analogue is significantly more active than the N-C(16)-alkyl or N-C(16)-acyl compounds that we had characterized earlier, indicating that basicity of the phosphate-recognizing cationic group, is not a determinant of LPS sequestration activity.

Protective effects of kaempferol on lipopolysaccharide-induced mastitis in mice.

PubMed

Cao, Rongfeng; Fu, Kaiqiang; Lv, Xiaopei; Li, Weishi; Zhang, Naisheng

2014-10-01

Kaempferol isolated from the root of Zingiberaceae plants galangal and other Chinese herbal medicines have been reported to have anti-inflammatory properties. However, the anti-inflammatory effects of kaempferol on lipopolysaccharide (LPS)-induced mastitis are unknown and their underlying molecular mechanisms remain to be explored. The aim of this study was to evaluate the effects of kaempferol on LPS-induced mouse mastitis. The mouse model of mastitis was induced by injection of LPS through the duct of mammary gland. Kaempferol was injected 1 h before and 12 h after induction of LPS intraperitoneally. The present results showed that kaempferol markedly reduced infiltration of neutrophilic granulocyte, activation of myeloperoxidase (MPO), expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in a dose-dependent manner, which were increased in LPS-induced mouse mastitis. Furthermore, kaempferol suppressed the phosphorylation of nuclear factor-κB (NF-κB) p65 subunit and the degradation of its inhibitor IκBα. All results suggest that anti-inflammatory effects of kaempferol against the LPS-induced mastitis possibly through inhibition of the NF-κB signaling pathway. Kaempferol may be a potential therapeutic agent for mastitis.

Lipopolysaccharide precipitates hepatic encephalopathy and increases blood-brain barrier permeability in mice with acute liver failure.

PubMed

Chastre, Anne; Bélanger, Mireille; Nguyen, Bich N; Butterworth, Roger F

2014-03-01

Acute liver failure (ALF) is frequently complicated by infection leading to precipitation of central nervous system complications such as hepatic encephalopathy (HE) and increased mortality. There is evidence to suggest that when infection occurs in ALF patients, the resulting pro-inflammatory mechanisms may be amplified that could, in turn, have a major impact on blood-brain barrier (BBB) function. The aim of this study was to investigate the role of endotoxemia on the progression of encephalopathy in relation to BBB permeability during ALF. Adult male C57-BL6 mice with ALF resulting from azoxymethane-induced toxic liver injury were administered trace amounts of the endotoxin component lipopolysaccharide (LPS). Effects on the magnitude of the systemic inflammatory response, liver pathology and BBB integrity were measured as a function of progression of HE, defined as time to loss of corneal reflex (coma). Lipopolysaccharide caused additional two- to seven-fold (P < 0.001) increases in circulating pro-inflammatory cytokines (TNF-α, IL-1β, IL-6), worsening liver pathology and associated increases of circulating transaminases as well as increased hyperammonaemia consistent with a further loss of viable hepatocytes. LPS treatment of ALF mice led to a rapid precipitation of hepatic coma and the BBB became permeable to the 25-kDa protein immunoglobulin G (IgG). This extravasation of IgG was accompanied by ignificant up-regulation of matrix metalloproteinase-9 (MMP-9), an endopeptidase known to modulate opening of the BBB in a wide range of neurological disorders. These findings represent the first direct evidence of inflammation-related BBB permeability changes in ALF. © 2013 John Wiley & Sons A/S. Publishing by John Wiley & Sons Ltd.

Involvement of nitric oxide in lipopolysaccharide induced anorexia.

PubMed

Riediger, Thomas; Cordani, Caroline; Potes, Catarina Soares; Lutz, Thomas A

2010-11-01

Treatment with the bacterial endotoxin lipopolysaccharide (LPS) is a commonly used model to induce disease-related anorexia. Following LPS treatment inducible nitric oxide synthase (iNOS) is expressed in the hypothalamic arcuate nucleus (ARC), where nitric oxide (NO) inhibits orexigenic neurons. Intracellular STAT signaling is triggered by inflammatory stimuli and has been linked to the transcriptional regulation of iNOS. We evaluated whether pharmacological blockade of iNOS by the specific inhibitor 1400W attenuates LPS-induced anorexia. Furthermore, we hypothesized that the tolerance to the anorectic effect occurring after repeated LPS treatment is paralleled by a blunted STAT3 phosphorylation in the ARC. Rats treated with a subcutaneous injection of 1400W (10 mg/kg) showed an attenuated anorectic LPS response relative to control rats receiving only LPS (100 µg/kg; i.p.). Similarly, iNOS blockade attenuated LPS-induced adipsia, hyperthermia, inactivity and the concomitant drop in energy expenditure. While single LPS treatment increased STAT3 phosphorylation in the ARC, rats treated repeatedly with LPS showed no anorectic response and also no STAT3 phosphorylation in the ARC after the second and third LPS injections, respectively. Hence, pSTAT3 signaling in the ARC might be part of the intracellular cascades translating pro-inflammatory stimuli into suppression of food intake. The current findings substantiate a role of iNOS dependent NO formation in disease-related anorexia. Copyright © 2010 Elsevier Inc. All rights reserved.

Melanocortin agonism as a viable strategy to control alveolar bone loss induced by oral infection.

PubMed

Madeira, Mila F M; Queiroz-Junior, Celso M; Montero-Melendez, Trinidad; Werneck, Silvia M C; Corrêa, Jôice D; Soriani, Frederico M; Garlet, Gustavo P; Souza, Daniele G; Teixeira, Mauro M; Silva, Tarcilia A; Perretti, Mauro

2016-12-01

Alveolar bone loss is a result of an aggressive form of periodontal disease (PD) associated with Aggregatibacter actinomycetemcomitans (Aa) infection. PD is often observed with other systemic inflammatory conditions, including arthritis. Melanocortin peptides activate specific receptors to exert antiarthritic properties, avoiding excessing inflammation and modulating macrophage function. Recent work has indicated that melanocortin can control osteoclast development and function, but whether such protection takes place in infection-induced alveolar bone loss has not been investigated. The purpose of this study was to evaluate the role of melanocortin in Aa-induced PD. Mice were orally infected with Aa and treated with the melanocortin analog DTrp 8 -γMSH or vehicle daily for 30 d. Then, periodontal tissue was collected and analyzed. Aa-infected mice treated with DTrp 8 -γMSH presented decreased alveolar bone loss and a lower degree of neutrophil infiltration in the periodontium than vehicle-treated animals; these actions were associated with reduced periodontal levels of TNF-α, IFN-γ, and IL-17A. In vitro experiments with cells differentiated into osteoclasts showed that osteoclast formation and resorptive activity were attenuated after treatment with DTrp 8 -γMSH. Thus, melanocortin agonism could represent an innovative way to tame overexuberant inflammation and, at the same time, preserve bone physiology, as seen after Aa infection.-Madeira, M. F. M., Queiroz-Junior, C. M., Montero-Melendez, T., Werneck, S. M. C., Corrêa, J. D., Soriani, F. M., Garlet, G. P., Souza, D. G., Teixeira, M. M., Silva, T. A., Perretti, M. Melanocortin agonism as a viable strategy to control alveolar bone loss induced by oral infection. © FASEB.

Immunologic burden links periodontitis to acute coronary syndrome.

PubMed

Liljestrand, John M; Paju, Susanna; Pietiäinen, Milla; Buhlin, Kåre; Persson, G Rutger; Nieminen, Markku S; Sinisalo, Juha; Mäntylä, Päivi; Pussinen, Pirkko J

2018-01-01

Periodontitis, a common polymicrobial inflammatory disease in the tooth supporting tissues, is a risk factor for coronary artery disease. One of the proposed underlying mechanisms is the systemic immune response to periodontal infection. We studied how serum antibodies against seven periodontal pathogens and their subgingival levels associate with each other, periodontitis, and coronary artery disease. The Parogene cohort included 505 Finnish patients (mean age 63 y) who underwent coronary angiography, and clinical and radiographic oral examinations. Coronary diagnosis was defined as no significant coronary artery disease (<50% stenosis, n = 152), stable coronary artery disease (≥50% stenosis, n = 184) and acute coronary syndrome (n = 169). Levels of subgingival Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Tannerella forsythia, Campylobacter rectus, and Fusobacterium nucleatum were determined by checkerboard DNA-DNA hybridization. Serum antibody (IgA/IgG) levels were analyzed with enzyme-linked immunosorbent assay (ELISA). Aggregate IgA/IgG burdens were calculated by summing and standardizing the serum antibody levels. Patients with active periodontitis were characterized by higher levels of subgingival bacteria and corresponding IgA/IgG response. Quartiles 2-4 of serum IgA/IgG burden indicated higher risk for acute coronary syndrome (OR 1.84, 95%CI 1.01-3.35 for IgA; OR 1.87, 95%CI 1.01-3.46 for IgG) independently of established cardiovascular risk factors, body mass index, number of teeth, subgingival bacterial levels and periodontal diagnosis. Our findings support the hypothesis that the association between periodontitis and cardiovascular diseases is partly mediated by the immunologic response for periodontal pathogens. Copyright © 2017 Elsevier B.V. All rights reserved.

The subgingival microbiota of Papillon-Lefèvre syndrome.

PubMed

Albandar, Jasim M; Khattab, Razan; Monem, Fawza; Barbuto, Sara M; Paster, Bruce J

2012-07-01

There is little information about the microbiologic profiles of periodontal lesions in Papillon-Lefèvre syndrome (PLS) and the significance of bacteria in the pathogenesis of periodontitis in these patients. This comprehensive analysis of the subgingival microbiota in patients with PLS used 16S ribosomal RNA (rRNA) clonal analysis and the 16S rRNA-based Human Oral Microbe Identification Microarray (HOMIM). Thirteen patients with PLS from seven unrelated families volunteered for this microbiologic study. Subgingival plaque was collected with sterile paper points from multiple sites with ≥5 mm probing depth, and whole genomic DNA was extracted. The 16S rRNA genes were amplified, cloned, and sequenced. The samples were then probed for ≈300 predominant oral bacterial species using the HOMIM. The most commonly detected phylotypes in the clonal analysis were Gemella morbillorum, Gemella haemolysans, Granulicatella adiacens, Lachnospiraceae OT 100 (EI074), Parvimonas micra, Selenomonas noxia, and Veillonella parvula. As a group, streptococci were commonly detected in these individuals. In the HOMIM analysis, a total of 170 bacterial species/phylotypes were detected, with a range of 40 to 80 species per patient with PLS. Of these, 12 bacterial species were detected in medium to high levels in ≥50% of the individuals. The high-frequency strains were clustered into eight groups: Aggregatibacter actinomycetemcomitans, Campylobacter spp., Capnocytophaga granulosa, G. morbillorum, P. micra, Porphyromonas endodontalis, Streptococcus spp., and Tannerella forsythia. The subgingival microbiota in PLS is diverse. Periodontal pathogens commonly associated with chronic and aggressive periodontitis and opportunistic pathogens may be associated with the development of severe periodontitis in patients with PLS.

Oral microbe-host interactions: influence of β-glucans on gene expression of inflammatory cytokines and metabolome profile.

PubMed

Silva, Viviam de Oliveira; Pereira, Luciano José; Murata, Ramiro Mendonça

2017-03-07

The aim of this study was to evaluate the effects of β-glucan on the expression of inflammatory mediators and metabolomic profile of oral cells [keratinocytes (OBA-9) and fibroblasts (HGF-1) in a dual-chamber model] infected by Aggregatibacter actinomycetemcomitans. The periodontopathogen was applied and allowed to cross the top layer of cells (OBA-9) to reach the bottom layer of cells (HGF-1) and induce the synthesis of immune factors and cytokines in the host cells. β-glucan (10 μg/mL or 20 μg/mL) were added, and the transcriptional factors and metabolites produced were quantified in the remaining cell layers and supernatant. The relative expression of interleukin (IL)-1-α and IL-18 genes in HGF-1 decreased with 10 μg/mL or 20 μg/mL of β-glucan, where as the expression of PTGS-2 decreased only with 10 μg/mL. The expression of IL-1-α increased with 20 μg/mL and that of IL-18 increased with 10 μg/mL in OBA-9; the expression of BCL 2, EP 300, and PTGS-2 decreased with the higher dose of β-glucan. The production of the metabolite 4-aminobutyric acid presented lower concentrations under 20 μg/mL, whereas the concentrations of 2-deoxytetronic acid NIST and oxalic acid decreased at both concentrations used. Acetophenone, benzoic acid, and pinitol presented reduced concentrations only when treated with 10 μg/mL of β-glucan. Treatment with β-glucans positively modulated the immune response and production of metabolites.

An in vitro biofilm model associated to dental implants: structural and quantitative analysis of in vitro biofilm formation on different dental implant surfaces.

PubMed

Sánchez, M C; Llama-Palacios, A; Fernández, E; Figuero, E; Marín, M J; León, R; Blanc, V; Herrera, D; Sanz, M

2014-10-01

The impact of implant surfaces in dental biofilm development is presently unknown. The aim of this investigation was to assess in vitro the development of a complex biofilm model on titanium and zirconium implant surfaces, and to compare it with the same biofilm formed on hydroxyapatite surface. Six standard reference strains were used to develop an in vitro biofilm over sterile titanium, zirconium and hydroxyapatite discs, coated with saliva within the wells of pre-sterilized polystyrene tissue culture plates. The selected species used represent initial (Streptococcus oralis and Actinomyces naeslundii), early (Veillonella parvula), secondary (Fusobacterium nucleatum) and late colonizers (Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans). The developed biofilms (growth time 1 to 120h) were studied with confocal laser scanning microscopy using a vital fluorescence technique and with low-temperature scanning electron microscopy. The number (colony forming units/biofilm) and kinetics of the bacteria within the biofilm were studied with quantitative PCR (qPCR). As outcome variables, the biofilm thickness, the percentage of cell vitality and the number of bacteria were compared using the analysis of variance. The bacteria adhered and matured within the biofilm over the three surfaces with similar dynamics. Different surfaces, however, demonstrated differences both in the thickness, deposition of the extracellular polysaccharide matrix as well as in the organization of the bacterial cells. While the formation and dynamics of an in vitro biofilm model was similar irrespective of the surface of inoculation (hydroxyapatite, titanium or zirconium), there were significant differences in regards to the biofilm thickness and three-dimensional structure. Copyright © 2014 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Association between Polycystic Ovary Syndrome, Oral Microbiota and Systemic Antibody Responses

PubMed Central

Akcalı, Aliye; Bostanci, Nagihan; Özçaka, Özgün; Öztürk-Ceyhan, Banu; Gümüş, Pınar; Buduneli, Nurcan; Belibasakis, Georgios N.

2014-01-01

Polycystic ovary syndrome (PCOS) is a hormonal disorder of women that not only is the leading cause of infertility but also shows a reciprocal link with oral health. This study aimed to investigate the hypothesis that the levels of putative periodontal pathogens in saliva and their antibody response in serum are elevated in PCOS, compared to systemic health. A total of 125 women were included in four groups; 45 women with PCOS and healthy periodontium, 35 women with PCOS and gingivitis, 25 systemically and periodontally healthy women, 20 systemically healthy women with gingivitis. Salivary levels of seven putative periodontal pathogens were analyzed by quantitative real-time polymerase chain reaction and serum antibody levels were analyzed by ELISA. In women with PCOS, salivary Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus oralis and Tannerella forsythia levels were higher than matched systemically healthy women, particularly in the case of gingivitis. Aggregatibacter actinomycetemcomitans and Treponema denticola levels were similar among study groups. The presence of PCOS also enhanced P. gingivalis, Prevotella intermedia and S. oralis serum antibody levels, when gingivitis was also present. Gingival inflammation correlated positively with levels of the studied taxa in saliva, particularly in PCOS. The presence of P. gingivalis and F. nucleatum in saliva also exhibited a strong positive correlation with the corresponding serum antibody levels. In conclusion, as an underlying systemic endocrine condition, PCOS may quantitatively affect the composition of oral microbiota and the raised systemic response to selective members of this microbial community, exerting a confounding role in resultant gingival inflammation and periodontal health. The most consistent effect appeared to be exerted on P. gingivalis. PMID:25232962

Comparative evaluation of the efficacy of a herbal mouthwash and chlorhexidine mouthwash on select periodontal pathogens: An in vitro and ex vivo study

PubMed Central

Pathan, Multazim Muradkhan; Bhat, Kishore Gajanan; Joshi, Vinayak Mahableshwar

2017-01-01

Background: Several herbal mouthwash and herbal extracts have been tested in vitro and in vivo in search of a suitable adjunct to mechanical therapy for long-term use. In this study, we aimed to look at the antimicrobial effect of the herbal mouthwash and chlorhexidine (CHX) mouthwash on select organisms in in vitro test and an ex vivo model. Materials and Methods: The antimicrobial effects were determined against standard strains of bacteria that are involved in different stages of periodontal diseases. The in vitro tests included determination of minimum inhibitory concentration (MIC) using broth dilution and agar diffusion. In the ex vivo part of the study supragingival dental plaque were obtained from 20 periodontally healthy adult volunteers. Descriptive analysis was done for the entire quantitative and qualitative variable recorded. Results: The MIC by broth dilution method found no statistically significant difference between the mouthwashes. The agar dilution method showed CHX was more effective as compared to the herbal mouthwash against standard strains of Streptococcus mutans, Streptococcus sanguinis, and Aggregatibacter actinomycetemcomitans. However, no difference was observed between the mouthwashes for Porphyromonas, Pseudomonas aeruginosa, and Fusobacterium nucleatum. The ex vivo results conclude that none of the selected mouthwashes were statistically significantly different from each other. Conclusion: In the present study, CHX showed higher levels of antimicrobial action than the herbal mouthwash against bacterial species. The results reinforce the earlier findings that the in vitro testing is sensitive to methods and due diligence is needed when extrapolating the data for further use. However, long-term use and in vivo effectiveness against the periopathogens need to be tested in well-planned clinical trials. PMID:29456300

IgG sera levels against a subset of periodontopathogens and severity of disease in aggressive periodontitis patients: a cross-sectional study of selected pocket sites.

PubMed

Saraiva, Luciana; Rebeis, Estela S; Martins, Eder de S; Sekiguchi, Ricardo T; Ando-Suguimoto, Ellen S; Mafra, Carlos Eduardo S; Holzhausen, Marinella; Romito, Giuseppe A; Mayer, Marcia P A

2014-10-01

To evaluate the association among serum immunoglobulin G (IgG) responses to Aggregatibacter actinomycetemcomitans (Aa) serotypes a, b and c, Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf) and clinical parameters in Aggressive Periodontitis (AP) subjects. Associations between periodontal pathogens and clinical and immunological parameters were also evaluated. Thirty-eight subjects diagnosed with generalized AP (GAP) and localized AP (LAP) were included. Ten healthy controls were also evaluated. Clinical parameters were assessed and percentages of subgingival levels of Aa, Pg and Tf (beyond bacterial load), were determined by quantitative real-time polymerase chain reaction. Serum IgG antibody levels against Aa, Pg and Tf were evaluated by enzyme-linked immunosorbent assay. Percentages of Aa, Pg and Tf were significantly higher in AP than in controls. The response to Aa serotype c was higher in LAP subjects than in controls. There were no differences in microbial composition or antibodies responses between GAP and LAP, except for IgG response to Tf. Pg levels were correlated with probing depth (PD), BoP and CAL in GAP but not in LAP subjects. Tf levels correlated with PD and CAL in GAP subjects. In GAP, the infection levels of Aa and Pg correlated with the corresponding IgG levels to Aa serotype c and Pg. Given the evidences that IgG response in AP patients correlated with bacterial infection level in GAP, but not in LAP, and that LAP patients lack a response to Tf, despite harbouring this species, our data suggest a difference in host immune defence between these two forms of aggressive periodontitis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Periowave demonstrates bactericidal activity against periopathogens and leads to improved clinical outcomes in the treatment of adult periodontitis

NASA Astrophysics Data System (ADS)

Street, Cale N.; Andersen, Roger; Loebel, Nicolas G.

2009-02-01

Periodontitis affects half of the U.S. population over 50, and is the leading cause of tooth loss after 35. It is believed to be caused by growth of complex bacterial biofilms on the tooth surface below the gumline. Photodynamic therapy, a technology used commonly in antitumor applications, has more recently been shown to exhibit antimicrobial efficacy. We have demonstrated eradication of the periopathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans in vitro using PeriowaveTM; a commercial photodisinfection system. In addition, several clinical studies have now demonstrated the efficacy of this treatment. A pilot study in the U.S. showed that 68% of patients treated with PeriowaveTM adjunctively to scaling and root planing (SRP) showed clinical attachment level increase of >1 mm, as opposed to 30% with SRP alone. In a subsequent larger study, a second PeriowaveTM treatment 6 weeks after initial treatment led to pocket depth improvements of >1.5 mm in 89% of patients. Finally, in the most recent multicenter, randomized, examiner-blinded study conducted on 121 subjects in Canada, PeriowaveTM treatment produced highly significant gains in attachment level (0.88 mm vs. 0.57 mm; p=0.003) and pocket depth (0.87 mm vs. 0.63 mm; p=0.01) as compared to SRP alone. In summary, PeriowaveTM demonstrated strong bactericidal activity against known periopathogens, and treatment of periodontitis using this system produced significantly better clinical outcomes than SRP alone. This, along with the absence of any adverse events in patients treated to date demonstrates that PDT is a safe and effective treatment for adult chronic periodontitis.

Adhesion of periodontal pathogens to self-ligating orthodontic brackets: An in-vivo prospective study.

PubMed

Jung, Woo-Sun; Kim, Kyungsun; Cho, Soha; Ahn, Sug-Joon

2016-09-01

Our aims were to analyze adhesion of periodontopathogens to self-ligating brackets (Clarity-SL [CSL], Clippy-C [CC] and Damon Q [DQ]) and to identify the relationships between bacterial adhesion and oral hygiene indexes. Central incisor brackets from the maxilla and mandible were collected from 60 patients at debonding after the plaque and gingival indexes were measured. Adhesions of Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Fusobacterium nucleatum (Fn), and Tannerella forsythia (Tf) were quantitatively determined using real-time polymerase chain reactions. Factorial analysis of variance was used to analyze bacterial adhesion in relation to bracket type and jaw position. Correlation coefficients were calculated to determine the relationships between bacterial adhesion and the oral hygiene indexes. Total bacteria showed greater adhesion to CSL than to DQ brackets, whereas Aa, Pg, and Pi adhered more to DQ than to CSL brackets. CC brackets showed an intermediate adhesion pattern between CSL and DQ brackets, but it did not differ significantly from either bracket type. Adhesion of Fn and Tf did not differ significantly among the 3 brackets. Most bacteria were detected in greater quantities in the mandibular than in the maxillary brackets. The plaque and gingival indexes were not strongly correlated with bacterial adhesion to the brackets. Because Aa, Pg, and Pi adhered more to the DQ brackets in the mandibular area, orthodontic patients with periodontal problems should be carefully monitored in the mandibular incisors where the distance between the bracket and the gingiva is small, especially when DQ brackets are used. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Comparison of the use of the Halimeter and the Oral Chroma™ in the assessment of the ability of common cultivable oral anaerobic bacteria to produce malodorous volatile sulfur compounds from cysteine and methionine.

PubMed

Salako, Nathanael O; Philip, Leeba

2011-01-01

To compare the use of the Halimeter and the Oral Chroma™ to assess the ability of common oral anaerobic bacteria isolated from the Kuwaiti population to produce volatile sulfur compounds (VSCs). Broth cultures of common anaerobes isolated from supragingival plaque were centrifuged and pellets resuspended in phosphate buffer (pH 7.7) with an optical density OD(550) of 0.3. 100 μl of this suspension and 870 μl of buffer were added in 2 sterile 15-ml head space vials. Reaction was initiated by addition of 30 μl of 33 mML-methionine and L-cysteine, respectively, in each vial and incubation at 37°C for 90 min. 500 μl of 3 M phosphoric acid was added to tubes and was kept aside for 10 min. Production of VSCs was measured using the Halimeter and the Oral Chroma. The major VSC producers identified by both Halimeter and Oral Chroma with L-cystenine as substrate were Campylobacter ureolyticus, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Aggregatibacter actinomycetemcomitans and Gemella morbillorum. The concentrations of hydrogen sulfide recorded by both Halimeter and Oral Chroma were essentially identical. With L-methionine as substrate, both Halimeter and Oral Chroma identified different complements of anaerobes with C. ureolyticus,P. gingivalis,Fusobacterium nucleatum and P. intermedia as major VSC producers. The concentrations of methyl mercaptan recorded by the Halimeter were lower compared to those assessed by the Oral Chroma. The results suggest that the Oral Chroma may produce a more comprehensive assessment of VSC production by oral microflora than the Halimeter. Copyright © 2010 S. Karger AG, Basel.

Dental caries and microbiota in children with black stain and non-discoloured dental plaque.

PubMed

Heinrich-Weltzien, R; Bartsch, B; Eick, S

2014-01-01

We aimed to assess caries experience and microbiota in systemically healthy children with black stain (BS) and non-discoloured plaque. Forty-six children with BS and 47 counterparts with non-discoloured plaque aged 7.9 ± 1.3 years were clinically examined. Dental caries was scored using WHO criteria. Samples of BS and non-discoloured dental plaque were collected from tooth surfaces. The DNA of the samples was extracted and real-time PCR was performed to determine the total number of bacteria and the species Streptococcus mutans, S. sobrinus, Lactobacillus sp., Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia and Fusobacterium nucleatum. Children with BS had lower DMFT (p = 0.013), lower DT values (p = 0.005) and a tendency to lower caries prevalence (p = 0.061) than children with non-discoloured plaque. Plaque samples of the BS group contained higher numbers of A. naeslundii (p = 0.005) and lower numbers of F. nucleatum (p = 0.001) and Lactobacillus sp. (p = 0.001) compared to the non-discoloured plaque samples of the control group. Comparing the children with BS and non-discoloured plaque, higher counts for A. naeslundii (p = 0.013) were observed in caries-free children with BS while in caries-affected children with BS, lower counts of F. nucleatum (p = 0.007) were found. Counts of Lactobacillus sp. were higher in non-discoloured plaque samples than in BS of caries-free and caries-affected children. Results suggest that the different microbial composition of BS might be associated with the lower caries experience in affected subjects. The role of black-pigmented bacteria associated with periodontitis needs further studies.

Periodontal Therapy Effects on Nitrite Related to Oral Bacteria: A 6-Month Randomized Clinical Trial.

PubMed

Cortelli, Sheila C; Costa, Fernando O; Rodrigues, Edson; Cota, Luis O M; Cortelli, Jose R

2015-08-01

Nitrite is a biologic factor relevant to oral and systemic homeostasis. Through an oral bacteria reduction process, it was suggested that periodontal therapy and chlorhexidine (CHX) rinse could affect nitrite levels, leading to negative effects, such as an increase in blood pressure. This 6-month randomized clinical trial evaluated the effects of periodontal therapeutic protocols on salivary nitrite and its relation to subgingival bacteria. One hundred patients with periodontitis were allocated randomly to debridement procedures in four weekly sections (quadrant scaling [QS]) or within 24 hours (full-mouth scaling [FMS]) in conjunction with a 60-day CHX (QS + CHX and FMS + CHX), placebo (QS + placebo and FMS + placebo), or no mouthrinse (QS + none and FMS + none) use. Real-time polymerase chain reaction determined total bacterial, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Streptococcus oralis, and Actinomyces naeslundii levels. Salivary nitrite concentration was determined with Griess reagent. Data were analyzed statistically at baseline and 3 and 6 months by analysis of variance, Kruskal-Wallis, Mann-Whitney U, and Spearman correlation tests (P <0.05). Nitrite concentrations did not tend to change over time. Regarding CHX use, there was a negative correlation between nitrite and total bacterial load at 6 months (FMS + CHX) and one positive correlation between P. gingivalis and nitrite at baseline (QS + CHX). Independently of rinse type, in the FMS group, nitrite correlated negatively with several microbial parameters and also with a higher percentage of deep periodontal pockets. The relationship between nitrite and bacterial levels appears weak. Short-term scaling exhibited a greater influence on nitrite concentrations then long-term CHX use.

Real-time PCR quantification of six periodontal pathogens in saliva samples from healthy young adults.

PubMed

Zhou, Xiaodong; Liu, Xiaoli; Li, Jing; Aprecio, Raydolfo M; Zhang, Wu; Li, Yiming

2015-05-01

The use of saliva as a diagnostic fluid for the evaluation of periodontal health has gained attention recently. Most published real-time PCR assays focused on quantification of bacteria in subgingival plaque, not in saliva. The aims of this study were to develop a real-time PCR assay for quantification of six periodontal pathogens in saliva and to establish a relationship between the amount of DNA (fg) and colony-forming unit (CFU). TaqMan primers/probe sets were used for the detection of Aggregatibacter actinomycetemcomitans (Aa), Eikenella corrodens (Ec), Fusobacterium nucleatum (Fn), Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Tannerella forsythia (Tf), and total bacteria. Six periodontal pathogens and total bacteria in saliva from 24 periodontally healthy individuals were determined. The relationship between the amount of DNA (fg) and CFU was established by measuring the concentrations of extracted bacterial DNA and CFU per milliliter of bacteria on agar plates. Fn, Ec, and Pi were detected in all saliva samples, while 58.5, 45.8, and 33.3% were detected for Tf, Pg, and Aa, respectively. Numbers of Ec and Fn in saliva were highly correlated (R(2) = 0.93, P < 0.01). The values of DNA (fg) per CFU ranged from 64 for Ec to 121 for Pg. The real-time PCR assay in combination with the relationship between DNA (fg) and CFU can be used to quantitate periodontal pathogens in saliva and estimate the number of live bacteria (CFU). This real-time PCR assay in combination with the relationship between DNA (fg) and CFU has the potential to be an adjunct in evaluation of periodontal health status.

Effects of tylosin, tilmicosin and tulathromycin on inflammatory mediators in bronchoalveolar lavage fluid of lipopolysaccharide-induced lung injury.

PubMed

Er, Ayse; Yazar, Enver

2012-12-01

The aim of this study was to determine the anti-inflammatory effects of macrolides through kinetic parameters in bronchoalveolar lavage fluid (BALF) of lipopolysaccharide-induced lung injury. Rats were divided into four groups: lipopolysaccharide (LPS), LPS + tylosin, LPS + tilmicosin and LPS + tulathromycin. BALF samples were collected at sampling times. TNF, IL-1β, IL-6, IL-10 and 13,14-dihydro-15-keto-prostaglandin F2α (PGM) and C-reactive protein (CRP) were analysed. Area under the curve (AUC) and maximum plasma concentration (Cmax) values of inflammatory mediators were determined by a pharmacokinetic computer programme. When inflammatory mediator concentrations were compared between the LPS group and other groups for each sampling time, the three macrolides had no pronounced depressor effect on cytokine levels, but they depressed PGM and CRP levels. In addition, tylosin and tilmicosin decreased the AUC0-24 level of TNF, while tilmicosin decreased the AUC0-24 level of IL-10. Tylosin and tulathromycin decreased the AUC0-24 of PGM, and all three macrolides decreased the AUC0-24 of CRP. Especially tylosin and tulathromycin may have more expressed anti-inflammatory effects than tilmicosin, via depressing the production of inflammatory mediators in the lung. The AUC may be used for determining the effects of drugs on inflammation. In this study, the antiinflammatory effects of these antibiotics were evaluated with kinetic parameters as a new and different approach.

Complete structural characterization of the lipid A fraction of a clinical strain of B. cepacia genomovar I lipopolysaccharide.

PubMed

Silipo, Alba; Molinaro, Antonio; Cescutti, Paola; Bedini, Emiliano; Rizzo, Roberto; Parrilli, Michelangelo; Lanzetta, Rosa

2005-05-01

Burkholderia cepacia, a Gram-negative bacterium ubiquitous in the environment, is a plant pathogen causing soft rot of onions. This microorganism has recently emerged as a life-threatening multiresistant pathogen in cystic fibrosis patients. An important virulence factor of B. cepacia is the lipopolysaccharide (LPS) fraction. Clinical isolates and environmental strains possess LPS of high inflammatory nature, which induces a high level production of cytokines. For the first time, the complete structure of the lipid A components isolated from the lipopolysaccharide fraction of a clinical strain of B. cepacia is described. The structural studies carried out by selective chemical degradations, MS, and NMR spectroscopy revealed multiple species differing in the acylation and in the phosphorylation patterns. The highest mass species was identified as a penta-acylated tetrasaccharide backbone containing two phosphoryl-arabinosamine residues in addition to the archetypal glucosamine disaccharide [Arap4N-l-beta-1-P-4-beta-D-GlcpN-(1-6)-alpha-D-GlcpN-1-P-1-beta-L-Arap4N]. Lipid A fatty acids substitution was also deduced, with two 3-hydroxytetradecanoic acids 14:0 (3-OH) in ester linkage, and two 3-hydroxyhexadecanoic acids 16:0 (3-OH) in amide linkage, one of which was substituted by a secondary 14:0 residue at its C-3. Other lipid A species present in the mixture and exhibiting lower molecular weight lacked one or both beta-L-Arap4N residues.

Microbiology of destructive periodontal disease in adolescent patients with congenital neutropenia. A report of 3 cases.

PubMed

van Winkelhoff, A J; Schouten-van Meeteren, A Y; Baart, J A; Vandenbroucke-Grauls, C M

2000-11-01

Congenital neutropenia is one condition that may predispose for destructive periodontal disease at a young age. In this report, we describe the microbiology of 3 adolescent patients with congenital neutropenia two of whom suffered from severe periodontitis. Microbiological testing of the parents was also performed in 1 case. DNA fingerprinting was used to study transmission of putative periodontal pathogens in this case. From 1 patient with periodontitis, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were isolated; a 2nd periodontitis patient was infected with P. gingivalis. A 3rd patient had gingivitis only and no A. actinomycetemcomitans or P. gingivalis were found. Using the amplified fragment length polymorphism DNA fingerprinting technique, bacterial transmission between the father and a patient was shown for A. actinomycetemcomitans but not for P. gingivalis.

Dose-dependent lipopolysaccharide-induced fetal brain injury in the guinea pig.

PubMed

Harnett, Erica L; Dickinson, Michelle A; Smith, Graeme N

2007-08-01

This study determined whether a lipopolysaccharide (LPS) dose-dependent increase in fetal brain injury occurs to further characterize the relationship between maternal inflammation and fetal brain injury. Pregnant guinea pigs (n = 59) at 70% gestation were injected intraperitoneally with 1, 5, 25, 50, 100, 200, or 300 microg LPS per kilogram of maternal body weight or an equivalent volume of vehicle. Animals were killed 7 days later. Maternal serum and amniotic fluid samples were assayed for proinflammatory cytokines tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6 using enzyme-linked immunosorbent assay kits. Fetal brains (n = 72) were stained for evidence of cell death with NeuroTACS stain. Seven days after LPS injections, cytokine concentrations in maternal serum and amniotic fluid were not different (P > .05) from controls. Levels of cell death in all brain regions examined were highest following the maternal administration of 300 mug/kg LPS (P < .05). The dose effect was brain region-dependent (P < .05). A threshold of maternal infection/inflammation exists, beyond which demonstrable fetal brain injury may result.

Efficient method for preparation of highly purified lipopolysaccharides by hydrophobic interaction chromatography.

PubMed

Muck, A; Ramm, M; Hamburger, M

1999-09-10

A method for the efficient preparation of highly purified lipopolysaccharides (LPSs) by hydrophobic interaction chromatography (HIC) has been developed. The procedure can be used for the purification of cell wall bound LPSs after hot phenol-water extraction and for the isolation of extracellular LPSs from the supernatant, respectively. The method described has been tested with artificial mixtures containing LPSs, polysaccharide, protein and RNA and subsequently employed for the preparative purification of two LPSs of different origin, namely the extracellular LPS secreted by Escherichia coli E49 into the culture medium, and the cell wall bound LPS from Pseudomonas aeruginosa VA11465/1. Compared to currently used methods for LPS purification such as enzymatic digestion and ultracentrifugation, the chromatographic separation reported here combines superior purity with minimal loss of LPS, high reproducibility and simple handling. The removal of contaminants such as protein, RNA and polysaccharides and the recovery of LPSs were monitored by appropriate assays.

Porphyromonas endodontalis lipopolysaccharides induce RANKL by mouse osteoblast in a way different from that of Escherichia coli lipopolysaccharide.

PubMed

Tang, Yin; Sun, Feifei; Li, Xiaoting; Zhou, Yuan; Yin, Shihai; Zhou, Xuedong

2011-12-01

Porphyromonas endodontalis lipopolysaccharide (LPS) has been shown to have a high positive rate in infected root canals and symptomatic apical periodontitis. It may play an integral role as a potent stimulator of inflammatory cytokines involved in apical lesions. The receptor activator of nuclear factor-κB ligand (RANKL) has been proven to be the key regulator of bone remodeling. This study investigated P. endodontalis LPS-induced RANKL production and LPS signaling in mouse osteoblasts. LPS-induced RANKL production in mouse osteoblast MC3T3-E1 cells was measured by Western blot and real-time polymerase chain reaction, and the Toll-like receptors (TLRs) were determined by the blocking test using anti-TLRs antibodies. In addition, specific inhibitors were used to analyze the intracellular signaling pathways. Escherichia coli LPS was used as the control. Both of the anti-TLR2 and anti-TLR4 antibodies significantly (P < .05) inhibited the expression of RANKL from osteoblasts stimulated with P. endodontalis LPS; only anti-TLR2 antibody had a significant (P < .05) inhibitory effect on E. coli LPS signaling. SP600125 (c-Jun N-terminal kinase [JNK] inhibitor) prevented the up-regulation of RANKL expression in P. endodontalis LPS-infected osteoblasts (P < .05). The inhibitory effect of wortmannin (phosphatidylinositol 3-kinase inhibitor) and PD98059 (mitogen-activated protein kinase [MAPK]/extracellular signal-regulated kinase [ERK] kinase-1/2 [MEK 1/2] inhibitor) were observed in E. coli LPS-treated mouse osteoblasts (P < .05). Results from this study showed that P. endodontalis LPS has the ability to promote the expression of RANKL in mouse osteoblasts, and this induction was mainly through the TLR2/4-JNK signaling pathway, a situation quite different from that of typical bacterial endotoxin (E. coli LPS). Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Screening and confirmatory analyses of flunixin in tissues and bodily fluids after intravenous or intramuscular administration to cull dairy cows with or without lipopolysaccharide challenge

USDA-ARS?s Scientific Manuscript database

Twenty cull dairy cows (645 ± 83 kg) were treated with 2.2 mg/kg bw flunixin by intravenous (IV) or intramuscular (IM) administration with, or without, exposure to lipopolysaccharide in a two factor balanced design. The usefulness of screening assays to identify violative flunixin levels in a varie...

GENETIC APPROACH TO THE STUDY OF EPIDEMIOLOGY AND PATHOGENESIS OF ACTINOBACILLUS ACTINOMYCETEMCOA4ITANS IN LOCALIZED JUVENILE PERIODONTITIS

PubMed Central

DiRienzo, J.M.; Slots, J.

2012-01-01

Summary Actinobacillus acrinomycetemcomirans isolates from periodontal pockets were examined for restriction fragment-length polymorphism using a characterized 4.7-kb DNA probe. A total of 6 patterns of RFLP was found in 133 isolates originating from 12 subjects. No relatedness was found between RFLP types and serotypes. Different periodontal sites within the same subject and different individuals within the same family sometimes showed only one type of A. actinomycetemcomitans RFLP. When members among the same family showed 2 RFLP types, children were always infected with the A. acfinomycefemcomitans strains found in at least one of the parents. These findings support the concept of familial spread of A. actinomycetemcomitans. A. actinomycetemcomitans RFLP type B, corresponding to reference strain JP2, seems to be particularly virulent, as indicated from the presence of RFLP type B in 3 subjects who converted from a healthy periodontal state to localized juvenile periodontitis. RFLP type B was not detected in any of the 21 A. acrinomycetemcomitans-infected patients with adult periodontitis. The RFLP method seems to be useful in determining the epidemiology and possibly the potential virulence of periodontal strains of A. actinomycetemcomitans. PMID:1982406

Effect of Thalidomide on Nitric Oxide Production in Lipopolysaccharide-Activated RAW 264.7 Cells

PubMed Central

Park, Eunkyue; Levis, WR; Greig, NH; Euisun, Jung; Schuller-Levis, G

2016-01-01

Thalidomide is anti-inflammatory under some conditions, yet has been reported to up regulate TH1 immunity measured by increased IL-2 and gamma interferon. We have assessed the effect of thalidomide and analogues, di- and tri-thiothalidomide, on a lipopolysaccharide (LPS) activated macrophage cell line (RAW 246.7 cells). Our findings showed that nitric oxide (NO) was significantly inhibited by thalidomide (15%) and its analogues (di-thiothalidomide; 15%, tri-thiothalidomide; 32%). The proinflammatory molecules TNF-α and IL-6 were not significantly inhibited. Pretreatment with thalidomide and analogues before activation was not different from simultaneous treatment. Inhibition of inducible nitric oxide synthase (iNOS) may prove to be an important target for the anti-inflammatory and anti-cancer effects of thalidomide and related immunomodulatory drugs (IMIDs). PMID:20514789

Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation.

PubMed

Reisenauer, Chris J; Bhatt, Dhaval P; Mitteness, Dane J; Slanczka, Evan R; Gienger, Heidi M; Watt, John A; Rosenberger, Thad A

2011-04-01

Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6 g/kg by oral gavage. In parallel experiments, free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 h. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 h. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive glial fibrillary acidic protein-positive astrocytes and activated CD11b-positive microglia by 40-50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of choline acetyltransferase (ChAT)-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. © 2011 The Authors

Up-regulation of microglial cathepsin C expression and activity in lipopolysaccharide-induced neuroinflammation.

PubMed

Fan, Kai; Wu, Xuefei; Fan, Bin; Li, Ning; Lin, Yongzhong; Yao, Yiwen; Ma, Jianmei

2012-05-20

Cathepsin C (Cat C) functions as a central coordinator for activation of many serine proteases in inflammatory cells. It has been recognized that Cat C is responsible for neutrophil recruitment and production of chemokines and cytokines in many inflammatory diseases. However, Cat C expression and its functional role in the brain under normal conditions or in neuroinflammatory processes remain unclear. Our previous study showed that Cat C promoted the progress of brain demyelination in cuprizone-treated mice. The present study further investigated the Cat C expression and activity in lipopolysaccharide (LPS)-induced neuroinflammation in vivo and in vitro. C57BL/6 J mice were intraperitoneally injected with either 0.9% saline or lipopolysaccharide (LPS, 5 mg/kg). Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to analyze microglial activation, TNF-α, IL-1β, IL-6, iNOS mRNAs expressions and cellular localization of Cat C in the brain. Nitrite assay was used to examine microglial activation in vitro; RT-PCR and ELISA were used to determine the expression and release of Cat C. Cat C activity was analyzed by cellular Cat C assay kit. Data were evaluated for statistical significance with paired t test. Cat C was predominantly expressed in hippocampal CA2 neurons in C57BL/6 J mice under normal conditions. Six hours after LPS injection, Cat C expression was detected in cerebral cortical neurons; whereas, twenty-four hours later, Cat C expression was captured in activated microglial cells throughout the entire brain. The duration of induced Cat C expression in neurons and in microglial cells was ten days and three days, respectively. In vitro, LPS, IL-1β and IL-6 treatments increased microglial Cat C expression in a dose-dependent manner and upregulated Cat C secretion and its activity. Taken together, these data indicate that LPS and proinflammatory cytokines IL-1β, IL-6 induce the expression, release and upregulate enzymatic activity of Cat C in

Up-regulation of microglial cathepsin C expression and activity in lipopolysaccharide-induced neuroinflammation

PubMed Central

2012-01-01

Background Cathepsin C (Cat C) functions as a central coordinator for activation of many serine proteases in inflammatory cells. It has been recognized that Cat C is responsible for neutrophil recruitment and production of chemokines and cytokines in many inflammatory diseases. However, Cat C expression and its functional role in the brain under normal conditions or in neuroinflammatory processes remain unclear. Our previous study showed that Cat C promoted the progress of brain demyelination in cuprizone-treated mice. The present study further investigated the Cat C expression and activity in lipopolysaccharide (LPS)-induced neuroinflammation in vivo and in vitro. Methods C57BL/6 J mice were intraperitoneally injected with either 0.9% saline or lipopolysaccharide (LPS, 5 mg/kg). Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to analyze microglial activation, TNF-α, IL-1β, IL-6, iNOS mRNAs expressions and cellular localization of Cat C in the brain. Nitrite assay was used to examine microglial activation in vitro; RT-PCR and ELISA were used to determine the expression and release of Cat C. Cat C activity was analyzed by cellular Cat C assay kit. Data were evaluated for statistical significance with paired t test. Results Cat C was predominantly expressed in hippocampal CA2 neurons in C57BL/6 J mice under normal conditions. Six hours after LPS injection, Cat C expression was detected in cerebral cortical neurons; whereas, twenty-four hours later, Cat C expression was captured in activated microglial cells throughout the entire brain. The duration of induced Cat C expression in neurons and in microglial cells was ten days and three days, respectively. In vitro, LPS, IL-1β and IL-6 treatments increased microglial Cat C expression in a dose-dependent manner and upregulated Cat C secretion and its activity. Conclusions Taken together, these data indicate that LPS and proinflammatory cytokines IL-1β, IL-6 induce the expression, release and

Relationship between size and surface modification of silica particles and enhancement and suppression of inflammatory cytokine production by lipopolysaccharide- or peptidoglycan-stimulated RAW264.7 macrophages

NASA Astrophysics Data System (ADS)

Uemura, Eiichiro; Yoshioka, Yasuo; Hirai, Toshiro; Handa, Takayuki; Nagano, Kazuya; Higashisaka, Kazuma; Tsutsumi, Yasuo

2016-06-01

Although nanomaterials are used in an increasing number of commodities, the relationships between their immunotoxicity and physicochemical properties such as size or surface characteristics are not fully understood. Here we demonstrated that pretreatment with amorphous silica particles (SPs) of various sizes (diameters of 10-1000 nm), with or without amine surface modification, significantly decreased interleukin 6 production by RAW264.7 macrophages following lipopolysaccharide or peptidoglycan stimulation. Furthermore, nanosized, but not microsized, SPs significantly enhanced tumor necrosis factor-α production in macrophages stimulated with lipopolysaccharide. This altered cytokine response was distinct from the inflammatory responses induced by treatment with the SPs alone. Additionally, the uptake of SPs into macrophages by phagocytosis was found to be crucial for the suppression of macrophage immune response to occur, irrespective of particle size or surface modification. Together, these results suggest that SPs may not only increase susceptibility to microbial infection, but that they may also be potentially effective immunosuppressants.

Total Lipopolysaccharide from the Human Gut Microbiome Silences Toll-Like Receptor Signaling.

PubMed

d'Hennezel, Eva; Abubucker, Sahar; Murphy, Leon O; Cullen, Thomas W

2017-01-01

Cohabitation of microbial communities with the host enables the formation of a symbiotic relationship that maintains homeostasis in the gut and beyond. One prevailing model suggests that this relationship relies on the capacity of host cells and tissues to remain tolerant to the strong immune stimulation generated by the microbiota such as the activation of Toll-like receptor 4 (TLR4) pathways by lipopolysaccharide (LPS). Indeed, gut microbial LPS is thought to be one of the most potent activators of innate immune signaling and an important mediator of the microbiome's influence on host physiology. In this study, we performed computational and experimental analyses of healthy human fecal samples to examine the TLR4 signaling capacity of the gut microbiota. These analyses revealed that an immunoinhibitory activity of LPS, conserved across the members of the order Bacteroidales and derived from an underacylated structural feature, silences TLR4 signaling for the entire consortium of organisms inhabiting the human gut. Comparative analysis of metagenomic data from the Human Microbiome Project and healthy-donor samples indicates that immune silencing via LPS is a microbe-intrinsic feature in all healthy adults. These findings challenge the current belief that robust TLR4 signaling is a feature of the microbiome and demonstrate that microbiome-derived LPS has the ability to facilitate host tolerance of gut microbes. These findings have broad implications for how we model host-microbe interactions and for our understanding of microbiome-linked disease. IMPORTANCE While the ability for humans to host a complex microbial ecosystem is an essential property of life, the mechanisms allowing for immune tolerance of such a large microbial load are not completely understood and are currently the focus of intense research. This study shows that an important proinflammatory pathway that is commonly triggered by pathogenic bacteria upon interaction with the host is, in fact

Rapid, highly sensitive detection of Gram-negative bacteria with lipopolysaccharide based disposable aptasensor.

PubMed

Zhang, Jian; Oueslati, Rania; Cheng, Cheng; Zhao, Ling; Chen, Jiangang; Almeida, Raul; Wu, Jayne

2018-07-30

Gram-negative bacteria are one of the most common microorganisms in the environment. Their differential detection and recognition from Gram-positive bacteria has been attracting much attention over the years. Using Escherichia coli (E. coli) as a model, we demonstrated on-site detection of Gram-negative bacteria by an AC electrokinetics-based capacitive sensing method using commercial microelectrodes functionalized with an aptamer specific to lipopolysaccharides. Dielectrophoresis effect was utilized to enrich viable bacteria to the microelectrodes rapidly, achieving a detection limit of 10 2 cells/mL within a 30 s' response time. The sensor showed a negligible response to Staphylococcus aureus (S. aureus), a Gram-positive species. The developed sensor showed significant advantages in sensitivity, selectivity, cost, operation simplicity, and response time. Therefore, this sensing method has shown great application potential for environmental monitoring, food safety, and real-time diagnosis. Copyright © 2018 Elsevier B.V. All rights reserved.

Stimulation of interleukin-6 production of periodontal ligament cells by Porphyromonas endodontalis lipopolysaccharide.

PubMed

Ogura, N; Shibata, Y; Kamino, Y; Matsuda, U; Hayakawa, M; Oikawa, T; Takiguchi, H; Izumi, H; Abiko, Y

1994-12-01

Interleukin-6 (IL-6), which is a multifunctional cytokine, has important roles in acute and chronic inflammation and may also be implicated in bone resorption. We examined the IL-6 production in periodontal ligament (PDL) cells which were treated with lipopolysaccharide (LPS) from several oral inflammatory pathogens. The LPS from Porphyromonas endodontalis, which was isolated from infected root canals and radicular cyst fluids, was more potent than the LPS from any other periodontal organisms examined. P. endodontalis LPS stimulated IL-6 release from PDL cells in a time- and dose-dependent manner. Northern blot hybridization analysis revealed that the IL-6 mRNA level in PDL cells was increased by P. endodontalis LPS. These results suggest that stimulation of the IL-6 release of PDL cells by P. endodontalis LPS may have a role in the progression of inflammation and alveolar bone resorption in periodontal and periapical diseases.

Characterization of a novel anti-lipopolysaccharide factor isoform (SpALF5) in mud crab, Scylla paramamosain.

PubMed

Sun, Wanwei; Wan, Weisong; Zhu, Shuo; Wang, Shasha; Wang, Shuqi; Wen, Xiaobo; Zheng, Huaiping; Zhang, Yueling; Li, Shengkang

2015-04-01

Anti-lipopolysaccharide factors (ALFs), the potential antimicrobial peptides that bind and neutralize lipopolysaccharide (LPS), are common effectors of innate immunity in crustaceans. In this study, a novel isoform of ALFs (SpALF5) was isolated from the hemocytes of mud crab Scylla paramamosain. The full-length 975bp SpALF5 contains a 375bp open reading frame (ORF) encoding 125 amino acids. Although SpALF5 exhibits a low degree of nucleotide homology with other reported ALFs, it contains the conserved amino acid sequence with a signal peptide and a LPS-binding domain including two conservative cysteine residues. The genomic organization of SpALF5 consists of four exons and three introns, with each intron containing one or more tandem repeats. Unlike most of ALFs mainly distributed in crab hemocytes, SpALF5 transcript was predominantly observed in the brain, muscle and skin, while barely detected in the hemocytes in our study. In situ hybridization assay also showed that SpALF5 mRNA was localized in brain, muscle and skin tissues of mud crab. Further, SpALF5 transcript was significantly up-regulated after challenge with LPS, polyinosinic polycytidylic acid (PolyI:C) (with the except of that in brain), Vibrio parahemolyticus or white spot syndrome virus (WSSV). The recombinant SpALF5 protein showed a varying degree of binding activity towards bacteria and fungus. Moreover, in vitro, the recombinant SpALF5 revealed a strong antimicrobial activity against Gram-negative bacteria (V. parahemolyticus, Vibrio alginolyticus, Escherichia coli, Aeromonas hydrophila) and fungus (Sacchromyces cerevisiae), but could only inhibited the growth of some Gram-positive bacteria like Staphylococcus aureus. The results suggest that SpALF5 is a potent immune protector and plays an important role in immune defense against invading pathogens in S. paramamosain. Copyright © 2014 Elsevier Ltd. All rights reserved.

Lipopolysaccharide (LPS) stimulation of fungal secondary metabolism

PubMed Central

Khalil, Zeinab G.; Kalansuriya, Pabasara; Capon, Robert J.

2014-01-01

We report on a preliminary investigation of the use the Gram-negative bacterial cell wall constituent lipopolysaccharide (LPS) as a natural chemical cue to stimulate and alter the expression of fungal secondary metabolism. Integrated high-throughput micro-cultivation and micro-analysis methods determined that 6 of 40 (15%) of fungi tested responded to an optimal exposure to LPS (0.6 ng/mL) by activating, enhancing or accelerating secondary metabolite production. To explore the possible mechanisms behind this effect, we employed light and fluorescent microscopy in conjunction with a nitric oxide (NO)-sensitive fluorescent dye and an NO scavenger to provide evidence that LPS stimulation of fungal secondary metabolism coincided with LPS activation of NO. Several case studies demonstrated that LPS stimulation can be scaled from single microplate well (1.5 mL) to preparative (>400 mL) scale cultures. For example, LPS treatment of Penicillium sp. (ACM-4616) enhanced pseurotin A and activated pseurotin A1 and pseurotin A2 biosynthesis, whereas LPS treatment of Aspergillus sp. (CMB-M81F) substantially accelerated and enhanced the biosynthesis of shornephine A and a series of biosynthetically related ardeemins and activated production of neoasterriquinone. As an indication of broader potential, we provide evidence that cultures of Penicillium sp. (CMB-TF0411), Aspergillus niger (ACM-4993F), Rhizopus oryzae (ACM-165F) and Thanatephorus cucumeris (ACM-194F) were responsive to LPS stimulation, the latter two examples being particular noteworthy as neither are known to produce secondary metabolites. Our results encourage the view that LPS stimulation can be used as a valuable tool to expand the molecular discovery potential of fungal strains that either have been exhaustively studied by or are unresponsive to traditional culture methodology. PMID:25379339

The Lipid A from Vibrio fischeri Lipopolysaccharide

PubMed Central

Phillips, Nancy J.; Adin, Dawn M.; Stabb, Eric V.; McFall-Ngai, Margaret J.; Apicella, Michael A.; Gibson, Bradford W.

2011-01-01

Vibrio fischeri, a bioluminescent marine bacterium, exists in an exclusive symbiotic relationship with the Hawaiian bobtail squid, Euprymna scolopes, whose light organ it colonizes. Previously, it has been shown that the lipopolysaccharide (LPS) or free lipid A of V. fischeri can trigger morphological changes in the juvenile squid's light organ that occur upon colonization. To investigate the structural features that might be responsible for this phenomenon, the lipid A from V. fischeri ES114 LPS was isolated and characterized by multistage mass spectrometry (MSn). A microheterogeneous mixture of mono- and diphosphorylated diglucosamine disaccharides was observed with variable states of acylation ranging from tetra- to octaacylated forms. All lipid A species, however, contained a set of conserved primary acyl chains consisting of an N-linked C14:0(3-OH) at the 2-position, an unusual N-linked C14:1(3-OH) at the 2′-position, and two O-linked C12:0(3-OH) fatty acids at the 3- and 3′-positions. The fatty acids found in secondary acylation were considerably more variable, with either a C12:0 or C16:1 at the 2-position, C14:0 or C14:0(3-OH) at the 2′-position, and C12:0 or no substituent at the 3′-position. Most surprising was the presence of an unusual set of modifications at the secondary acylation site of the 3-position consisting of phosphoglycerol (GroP), lysophosphatidic acid (GroP bearing C12:0, C16:0, or C16:1), or phosphatidic acid (GroP bearing either C16:0 + C12:0 or C16:0 + C16:1). Given their unusual nature, it is possible that these features of the V. fischeri lipid A may underlie the ability of E. scolopes to recognize its symbiotic partner. PMID:21498521

Melatonin protects against myocardial hypertrophy induced by lipopolysaccharide.

PubMed

Lu, Qi; Yi, Xin; Cheng, Xiang; Sun, Xiaohui; Yang, Xiangjun

2015-04-01

Melatonin is thought to have the ability of antiatherogenic, antioxidant, and vasodilatory. It is not only a promising protective in acute myocardial infarction but is also a useful tool in the treatment of pathological remodeling. However, its role in myocardial hypertrophy remains unclear. In this study, we investigated the protective effects of melatonin on myocardial hypertrophy induced by lipopolysaccharide (LPS) and to identify their precise mechanisms. The cultured myocardial cell was divided into six groups: control group, LPS group, LPS + ethanol (4%), LPS + melatonin (1.5 mg/ml) group, LPS + melatonin (3 mg/ml) group, and LPS + melatonin (6 mg/ml) group. The morphologic change of myocardial cell was observed by inverted phase contrast microscope. The protein level of myocardial cell was measured by Coomassie brilliant blue protein kit. The secretion level of tumor necrosis factor-α (TNF-α) was evaluated by enzyme-linked immunosorbent assay (ELISA). Ca(2+) transient in Fura-2/AM-loaded cells was measured by Till image system. The expression of Ca(2+)/calmodulin-dependent kinase II (CaMKII) and calcineurin (CaN) was measured by Western blot analysis. Our data demonstrated that LPS induced myocardial hypertrophy, promoted the secretion levels of TNF-α, and increased Ca(2+) transient level and the expression of CaMKII and CaN. Administration of melatonin 30 min prior to LPS stimulation dose-dependently attenuated myocardial hypertrophy. In conclusion, the results revealed that melatonin had the potential to protect against myocardial hypertrophy induced by LPS in vitro through downregulation of the TNF-α expression and retains the intracellular Ca(2+) homeostasis.

Detoxification of Salmonella typhimurium lipopolysaccharide by ionizing radiation.

PubMed

Previte, J J; Chang, Y; el-Bisi, H M

1967-05-01

The efficiency of ionizing radiation in detoxifying the lethal determinant(s) of the lipopolysaccharide (LPS) of Salmonella typhimurium, S. enteritidis, and Escherichia coli in aqueous solution and associated with heat-killed S. typhimurium cells in suspension decreased with doses above 1 Mrad. The 50% end point of inactivation was more than 7.0 Mrad for heat-killed salmonellae and 4.8, 4.5, and 1.0 Mrad for the LPS of S. typhimurium, S. enteritidis, and E. coli, respectively. After exposure to 20 Mrad, S. typhimurium LPS retained a small portion of its lethal properties although the ld(50) was much greater than 9.5 mg per 20-g mouse. However, at -184 C, no inactivation of the lethal determinant(s) occurred after exposure to as much as 20 Mrad. This demonstrated the significance of the indirect effect and the mobility and formation of free radicals. At 22 C, the optical density at 400 mmu increased and the pH decreased with increasing radiation dose, but no qualitative changes were observed in the infrared spectrum. No change was observed in the pyrogenicity of S. typhimurium LPS; a slight decrease in antigenicity was revealed when 6 days, but not when 1 day, elapsed between vaccination and challenge in the mouse protection test. The results were interpreted as evidence of the existence of two or more lethal and antigenic determinants. The differential effect of radiation on these properties and on the pyrogenic component(s) probably are indicative of separate functional sites for lethal, antigenic, and pyrogenic activities.

HSP90 Inhibition Suppresses Lipopolysaccharide-Induced Lung Inflammation In Vivo

PubMed Central

Lilja, Andrew; Weeden, Clare E.; McArthur, Kate; Nguyen, Thao; Donald, Alastair; Wong, Zi Xin; Dousha, Lovisa; Bozinovski, Steve; Vlahos, Ross; Burns, Christopher J.; Asselin-Labat, Marie-Liesse; Anderson, Gary P.

2015-01-01

Inflammation is an important component of cancer diathesis and treatment-refractory inflammation is a feature of many chronic degenerative lung diseases. HSP90 is a 90kDa protein which functions as an ATP-dependent molecular chaperone that regulates the signalling conformation and expression of multiple protein client proteins especially oncogenic mediators. HSP90 inhibitors are in clinical development as cancer therapies but the myeleosuppressive and neutropenic effect of first generation geldanamycin-class inhibitors has confounded studies on the effects on HSP90 inhibitors on inflammation. To address this we assessed the ability of Ganetespib, a non-geldanamycin HSP90 blocker, to suppress lipopolysaccharide (LPS)-induced cellular infiltrates, proteases and inflammatory mediator and transcriptional profiles. Ganetespib (10–100mg/kg, i.v.) did not directly cause myelosuppression, as assessed by video micrography and basal blood cell count, but it strongly and dose-dependently suppressed LPS-induced neutrophil mobilization into blood and neutrophil- and mononuclear cell-rich steroid-refractory lung inflammation. Ganetespib also suppressed B cell and NK cell accumulation, inflammatory cytokine and chemokine induction and MMP9 levels. These data identify non-myelosuppresssive HSP90 inhibitors as potential therapies for inflammatory diseases refractory to conventional therapy, in particular those of the lung. PMID:25615645

Establishment of hydrochloric acid/lipopolysaccharide-induced pelvic inflammatory disease model.

PubMed

Oh, Yeonsu; Lee, Jaehun; Kim, Hyeon-Cheol; Hahn, Tae-Wook; Yoon, Byung-Il; Han, Jeong-Hee; Kwon, Yong-Soo; Park, Joung Jun; Koo, Deog-Bon; Rhee, Ki-Jong; Jung, Bae Dong

2016-09-30

Pelvic inflammatory disease (PID), which is one of the most problematic complications experienced by women with sexually transmitted diseases, frequently causes secondary infections after reproductive abnormalities in veterinary animals. Although the uterus is self-protective, it becomes fragile during periods or pregnancy. To investigate PID, bacteria or lipopolysaccharide (LPS) extracted from gram negative bacteria has been used to induce the disease in several animal models. However, when LPS is applied to the peritoneum, it often causes systemic sepsis leading to death and the PID was not consistently demonstrated. Hydrochloric acid (HCl) has been used to induce inflammation in the lungs and stomach but not tested for reproductive organs. In this study, we developed a PID model in mice by HCl and LPS sequential intracervical (i.c.) administration. The proinflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor-α, were detected in the mouse uterus by western blot analysis and cytokine enzyme-linked immunosorbent assay after HCl (25 mg/kg) administration i.c. followed by four LPS (50 mg/kg) treatments. Moreover, mice exhibited increased infiltration of neutrophils in the endometrium and epithelial layer. These results suggest that ic co-administration of HCl and LPS induces PID in mice. This new model may provide a consistent and reproducible PID model for future research.

Alkaline Phosphatase Protects Lipopolysaccharide-Induced Early Pregnancy Defects in Mice

PubMed Central

Lei, Wei; Ni, Hua; Herington, Jennifer; Reese, Jeff; Paria, Bibhash C.

2015-01-01

Excessive cytokine inflammatory response due to chronic or superphysiological level of microbial infection during pregnancy leads to pregnancy complications such as early pregnancy defects/loss and preterm birth. Bacterial toxin lipopolysaccharide (LPS), long recognized as a potent proinflammatory mediator, has been identified as a risk factor for pregnancy complications. Alkaline phosphatase (AP) isozymes have been shown to detoxify LPS by dephosphorylation. In this study, we examined the role of alkaline phosphatase (AP) in mitigating LPS-induced early pregnancy complications in mice. We found that 1) the uterus prior to implantation and implantation sites following embryo implantation produce LPS recognition and dephosphorylation molecules TLR4 and tissue non-specific AP (TNAP) isozyme, respectively; 2) uterine TNAP isozyme dephosphorylates LPS at its sites of production; 3) while LPS administration following embryo implantation elicits proinflammatory cytokine mRNA levels at the embryo implantation sites (EISs) and causes early pregnancy loss, dephosphorylated LPS neither triggers proinflammatory cytokine mRNA levels at the EISs nor induces pregnancy complications; 4) AP isozyme supplementation to accelerate LPS detoxification attenuates LPS-induced pregnancy complications following embryo implantation. These findings suggest that a LPS dephosphorylation strategy using AP isozyme may have a unique therapeutic potential to mitigate LPS- or Gram-negative bacteria-induced pregnancy complications in at-risk women. PMID:25910276

Alkaline phosphatase protects lipopolysaccharide-induced early pregnancy defects in mice.

PubMed

Lei, Wei; Ni, Hua; Herington, Jennifer; Reese, Jeff; Paria, Bibhash C

2015-01-01

Excessive cytokine inflammatory response due to chronic or superphysiological level of microbial infection during pregnancy leads to pregnancy complications such as early pregnancy defects/loss and preterm birth. Bacterial toxin lipopolysaccharide (LPS), long recognized as a potent proinflammatory mediator, has been identified as a risk factor for pregnancy complications. Alkaline phosphatase (AP) isozymes have been shown to detoxify LPS by dephosphorylation. In this study, we examined the role of alkaline phosphatase (AP) in mitigating LPS-induced early pregnancy complications in mice. We found that 1) the uterus prior to implantation and implantation sites following embryo implantation produce LPS recognition and dephosphorylation molecules TLR4 and tissue non-specific AP (TNAP) isozyme, respectively; 2) uterine TNAP isozyme dephosphorylates LPS at its sites of production; 3) while LPS administration following embryo implantation elicits proinflammatory cytokine mRNA levels at the embryo implantation sites (EISs) and causes early pregnancy loss, dephosphorylated LPS neither triggers proinflammatory cytokine mRNA levels at the EISs nor induces pregnancy complications; 4) AP isozyme supplementation to accelerate LPS detoxification attenuates LPS-induced pregnancy complications following embryo implantation. These findings suggest that a LPS dephosphorylation strategy using AP isozyme may have a unique therapeutic potential to mitigate LPS- or Gram-negative bacteria-induced pregnancy complications in at-risk women.

[Endoplasmic reticulum stress mediates lipopolysaccharide-induced apoptosis in rat hepatocyte].

PubMed

Ji, Ying-Lei; Yan, Jun; Wang, Yan-Sha; Liu, Yi-Chang; Gu, Zhen-Yong

2014-02-01

To investigate the role of endoplasmic reticulum stress (ERS) in lipopolysaccharide (LPS)-induced hepatocyte apoptosis. Cells of the rat hepatocyte line BRL were cultured. The hepatocytes were treated with LPS, ERS inducer thapsigargin (TG), and ERS inhibitor 4-phenylbutyric acid (4-PBA), respectively or in their different combination. The cell viability was measured by MTT assay. The cyto-nuclear morphological changes of apoptosis cells were detected by the fluorescent dye Hoechst 33258. The apoptosis rate was assessed by flow cytometry with Annexin V-FITC/PI double-staining. Expressions of GRP78 as ERS marker protein, CHOP, caspase-12 and cleaved-caspase-3 as ERS related protein were detected by Western blotting. LPS could cause a decrease in cell viability and an increase in apoptosis rate in a dose- and time-dependent manner. The expression of GRP78, CHOP, caspase-12 and cleaved-caspase-3 proteins were significantly increased with LPS treatment. TG led to a marked decrease in cell viability and an increase in apoptosis rate, which aggravated the hepatocyte injury induced by LPS; whereas 4-PBA alleviated LPS-induced apoptosis. ERS mediates LPS-induced hepatocyte injuries, indicating that ERS may play a vital role in the pathogenesis of LPS-induced hepatocyte injuries.

Effect of lipopolysaccharide on the hemocyte apoptosis of Eriocheir sinensis *

PubMed Central

Xu, Hai-sheng; Lyu, Sun-jian; Xu, Jie-hao; Lu, Bin-jie; Zhao, Jing; Li, Song; Li, Yi-qun; Chen, Yu-yin

2015-01-01

In the present study, we investigated the possible toxicity mechanism of lipopolysaccharide (LPS) extracted from Gram-negative bacteria in Eriocheir sinensis hemocytes. Apoptotic hemocytes and reactive oxygen species (ROS) production induced by the LPS were monitored by the combination of flow cytometry and microscope observation. It was shown that LPS induced serious damage on the DNA and morphological changes in hemocytes, including cell shrinkage, fracture of nucleus membrane, margination, condensation and fragmentation of chromatin, and formation of apoptotic bodies indicating obvious hemocyte apoptosis. As compared with the control group, the apoptotic cell ratio increased to 30.61% and 39.01% after 1-h exposure and 57.72% and 75.01% after 2-h exposure to 1 and 10 μg/ml LPS, respectively (P<0.05). Significant outburst of ROS production was observed in LPS-treated hemocytes with approximately 176.6% of relative dichlorofluorescein mean fluorescence at 1-h exposure, followed by a drastic decline (P<0.05). These results indicated that LPS would induce oxidative stress on hemocytes from E. sinensis and cause ROS burst, DNA damage, and subsequently apoptosis. The process of ROS-mediated apoptosis might be one of the potential toxicity mechanisms of LPS on crustacean hemocytes. PMID:26642180

Epigallocatechin gallate (EGCG) suppresses lipopolysaccharide-induced inflammatory bone resorption, and protects against alveolar bone loss in mice.

PubMed

Tominari, Tsukasa; Matsumoto, Chiho; Watanabe, Kenta; Hirata, Michiko; Grundler, Florian M W; Miyaura, Chisato; Inada, Masaki

2015-01-01

Epigallocatechin gallate (EGCG), a major polyphenol in green tea, possesses antioxidant properties and regulates various cell functions. Here, we examined the function of EGCG in inflammatory bone resorption. In calvarial organ cultures, lipopolysaccharide (LPS)-induced bone resorption was clearly suppressed by EGCG. In osteoblasts, EGCG suppressed the LPS-induced expression of COX-2 and mPGES-1 mRNAs, as well as prostaglandin E2 production, and also suppressed RANKL expression, which is essential for osteoclast differentiation. LPS-induced bone resorption of mandibular alveolar bones was attenuated by EGCG in vitro, and the loss of mouse alveolar bone mass was inhibited by the catechin in vivo.

Neisseria meningitidis expressing lgtB lipopolysaccharide targets DC-SIGN and modulates dendritic cell function.

PubMed

Steeghs, Liana; van Vliet, Sandra J; Uronen-Hansson, Heli; van Mourik, Andries; Engering, Anneke; Sanchez-Hernandez, Martha; Klein, Nigel; Callard, Robin; van Putten, Jos P M; van der Ley, Peter; van Kooyk, Yvette; van de Winkel, Jan G J

2006-02-01

Neisseria meningitidis lipopolysaccharide (LPS) has been identified as a major determinant of dendritic cell (DC) function. Here we report that one of a series of meningococcal mutants with defined truncations in the lacto-N-neotetraose outer core of the LPS exhibited unique strong adhesion and internalization properties towards DC. These properties were mediated by interaction of the GlcNAc(beta1-3)-Gal(beta1-4)-Glc-R oligosaccharide outer core of lgtB LPS with the dendritic-cell-specific ICAM-3 grabbing non-integrin (DC-SIGN) lectin receptor. Activation of DC-SIGN with this novel oligosaccharide ligand skewed T-cell responses driven by DC towards T helper type 1 activity. Thus, the use of lgtB LPS may provide a powerful instrument to selectively induce the desired arm of the immune response and potentially increase vaccine efficacy.

Resveratrol counteracts lipopolysaccharide-mediated microglial inflammation by modulating a SOCS-1 dependent signaling pathway.

PubMed

Dragone, Teresa; Cianciulli, Antonia; Calvello, Rosa; Porro, Chiara; Trotta, Teresa; Panaro, Maria Antonietta

2014-09-01

Brain damage or exposure to inflammatory agents provokes the activation of microglia and secretion of pro-inflammatory and neurotoxic mediators responsible for neuronal loss. Several lines of evidence show that resveratrol, a natural non-flavonoid polyphenol, may exert a neuroprotective action in neurodegenerative diseases. Suppressor of cytokine signaling (SOCS) proteins are a family of eight members expressed by immune cells and the central nervous system (CNS) cells, that regulate immune processes within the CNS, including microglia activation. We demonstrate that resveratrol had anti-inflammatory effects in murine N13 microglial cells stimulated with lipopolysaccharide (LPS), through up-regulating SOCS-1 expression. Interestingly, in SOCS-1-silenced cells resveratrol failed to play a protective role after LPS treatment. Our data demonstrate that resveratrol can impair microglia activation by activating a SOCS-1 mediated signaling pathway. Copyright © 2014 Elsevier Ltd. All rights reserved.

Intestinal Alkaline Phosphatase Detoxifies Lipopolysaccharide and Prevents Inflammation in Response to the Gut Microbiota

PubMed Central

Bates, Jennifer M.; Akerlund, Janie; Mittge, Erika; Guillemin, Karen

2009-01-01

SUMMARY Vertebrates harbor abundant lipopolysaccharide (LPS) or endotoxin in their gut microbiota. Here we demonstrate that the brush border enzyme intestinal alkaline phosphatase (Iap), which dephosphorylates LPS, is induced during establishment of the microbiota and plays a crucial role in promoting mucosal tolerance to gut bacteria in zebrafish. We demonstrate that Iap deficient animals are hypersensitive to LPS toxicity through a mechanism mediated by Myd88 and Tumor Necrosis Factor Receptor (Tnfr). We further show that the endogenous microbiota establish the normal homeostatic level of neutrophils in the intestine through a process involving Myd88 and Tnfr. Iap deficient animals exhibit excessive intestinal neutrophil influx, similar to wild type animals exposed to LPS. When reared germ-free, however, the intestines of Iap deficient animals are devoid of neutrophils, demonstrating that Iap functions to prevent inflammatory responses to resident gut bacteria. PMID:18078689

Effect of thalidomide on nitric oxide production in lipopolysaccharide-activated RAW 264.7 cells.

PubMed

Park, Eunkyue; Levis, William R; Greig, Nigel; Jung, Euisun; Schuller-Levis, Georgia

2010-04-01

Thalidomide is anti-inflammatory under some conditions, yet has been reported to up-regulate Th1 (T helper 1) immunity measured by increased IL-2 (Interleukin-2) and gamma interferon. The authors have assessed the effect of thalidomide and analogues, di- and tri-thiothalidomide, on a lipopolysaccharide (LPS) activated macrophage cell line (RAW 246.7 cells). The authors' findings showed that nitric oxide (NO) was significantly inhibited by thalidomide (15%) and its analogues (di-thiothalidomide; 15%, tri-thiothalidomide; 32%). The proinflammatory molecules TNF-alpha (tumor necrosis factor-alpha) and IL-6 were not significantly inhibited. Pretreatment with thalidomide and analogues before activation was not different from simultaneous treatment. Inhibition of inducible nitric oxide synthase (iNOS) may prove to be an important target for the anti-inflammatory and anti-cancer effects of thalidomide and related immunomodulatory drugs (IMiDs).

Identification of the lipopolysaccharide modifications controlled by the Salmonella PmrA/PmrB system mediating resistance to Fe(III) and Al(III)

PubMed Central

Nishino, Kunihiko; Hsu, Fong-Fu; Turk, John; Cromie, Michael J; Wösten, Marc M S M; Groisman, Eduardo A

2006-01-01

Iron is an essential metal but can be toxic in excess. While several homeostatic mechanisms prevent oxygen-dependent killing promoted by Fe(II), little is known about how cells cope with Fe(III), which kills by oxygen-independent means. Several Gram-negative bacterial species harbour a regulatory system – termed PmrA/PmrB – that is activated by and required for resistance to Fe(III). We now report the identification of the PmrA-regulated determinants mediating resistance to Fe(III) and Al(III) in Salmonella enterica serovar Typhimurium. We establish that these determinants remodel two regions of the lipopolysaccharide, decreasing the negative charge of this major constituent of the outer membrane. Remodelling entails the covalent modification of the two phosphates in the lipid A region with phosphoethanolamine and 4-aminoarabinose, which has been previously implicated in resistance to polymyxin B, as well as dephosphorylation of the Hep(II) phosphate in the core region by the PmrG protein. A mutant lacking the PmrA-regulated Fe(III) resistance genes bound more Fe(III) than the wild-type strain and was defective for survival in soil, suggesting that these PmrA-regulated lipopolysaccharide modifications aid Salmonella's survival and spread in non-host environments. PMID:16803591

Detection of lipopolysaccharides in serum using a waveguide-based optical biosensor

NASA Astrophysics Data System (ADS)

Noormohamed, Aneesa; Stromberg, Loreen R.; Anderson, Aaron S.; Karim, Zachary; Dighe, Priya; Kempaiah, Prakasha; Ong'echa, John M.; Perkins, Douglas J.; Doggett, Norman; McMahon, Benjamin; Mukundan, Harshini

2017-02-01

Direct ultra-sensitive detection of pathogen biomarkers in blood could provide a universal strategy for diagnosis of bacterial infections, which remain a leading cause of morbidity and mortality in many areas of the world. Many factors complicate diagnosis, including the presence of multiple co-infections in a given patient, and lack of infrastructure in rural settings. In some pediatric patients, such as those in areas with poor resources, an additional challenge exists with low sample volumes due to age and other health factors such as anemia and dehydration. Our team is working on developing novel diagnostic assays, with a waveguide-based biosensor platform, to rapidly and specifically identify pathogen biomarkers from small samples of serum or plasma, allowing for the timely and sensitive diagnosis of infection at the point of care. In addition to the platform, we have developed novel membrane insertion and lipoprotein capture assay methods, to capture lipidated pathogen biomarkers in aqueous blood, by virtue of their interactions with host lipoprotein carriers. Herein, we demonstrate our efforts to adapt the lipoprotein capture assay for the detection of small concentrations of pathogen-secreted lipopolysaccharides in aqueous blood, with the ultimate aim of diagnosing Gram-negative infections effectively.

Lipopolysaccharide Binding Protein and Oxidative Stress in a Multiple Sclerosis Model.

PubMed

Escribano, Begoña M; Medina-Fernández, Francisco J; Aguilar-Luque, Macarena; Agüera, Eduardo; Feijoo, Montserrat; Garcia-Maceira, Fe I; Lillo, Rafael; Vieyra-Reyes, Patricia; Giraldo, Ana I; Luque, Evelio; Drucker-Colín, René; Túnez, Isaac

2017-01-01

Recent findings in experimental autoimmune encephalomyelitis (EAE) suggest that altering certain bacterial populations present in the gut may lead to a proinflammatory condition, that could result in the development of multiple sclerosis (MS). Also, Reactive Oxygen Species seem to be involved in the course of MS. In this study, it has been aimed to relate all these variables starting from an analysis of the lipopolysaccharide (LPS) and LPS-binding protein (LBP) with the determination of parameters related to oxidative stress in the blood, brain and spinal cord. For this purpose, samples obtained from EAE rats and relapsing-remitting (RRMS) MS patients were used. In addition, EAE rats were treated with Natalizumab, N-acetyl-cysteine and dimethyl fumarate. Natalizumab was also employed in RRMS. The results of this study revealed an improvement in the clinical symptoms of the EAE and MS with the treatments, as well as a reduction in the oxidative stress parameters and in LBP. Correlations between the clinical variables of the disease, i.e. oxidative damage and LBP, were established. Although the conclusions of this research are indeed relevant, further investigation would be necessary to establish the intrinsic mechanisms of the MS-oxidative stress-microbiota relationship.

Vildagliptin ameliorates pulmonary fibrosis in lipopolysaccharide-induced lung injury by inhibiting endothelial-to-mesenchymal transition.

PubMed

Suzuki, Toshio; Tada, Yuji; Gladson, Santhi; Nishimura, Rintaro; Shimomura, Iwao; Karasawa, Satoshi; Tatsumi, Koichiro; West, James

2017-10-16

Pulmonary fibrosis is a late manifestation of acute respiratory distress syndrome (ARDS). Sepsis is a major cause of ARDS, and its pathogenesis includes endotoxin-induced vascular injury. Recently, endothelial-to-mesenchymal transition (EndMT) was shown to play an important role in pulmonary fibrosis. On the other hand, dipeptidyl peptidase (DPP)-4 was reported to improve vascular dysfunction in an experimental sepsis model, although whether DPP-4 affects EndMT and fibrosis initiation during lipopolysaccharide (LPS)-induced lung injury is unclear. The aim of this study was to investigate the anti-EndMT effects of the DPP-4 inhibitor vildagliptin in pulmonary fibrosis after systemic endotoxemic injury. A septic lung injury model was established by intraperitoneal injection of lipopolysaccharide (LPS) in eight-week-old male mice (5 mg/kg for five consecutive days). The mice were then treated with vehicle or vildagliptin (intraperitoneally, 10 mg/kg, once daily for 14 consecutive days from 1 day before the first administration of LPS.). Flow cytometry, immunohistochemical staining, and quantitative polymerase chain reaction (qPCR) analysis was used to assess cell dynamics and EndMT function in lung samples from the mice. Lung tissue samples from treated mice revealed obvious inflammatory reactions and typical interstitial fibrosis 2 days and 28 days after LPS challenge. Quantitative flow cytometric analysis showed that the number of pulmonary vascular endothelial cells (PVECs) expressing alpha-smooth muscle actin (α-SMA) or S100 calcium-binding protein A4 (S100A4) increased 28 days after LPS challenge. Similar increases in expression were also confirmed by qPCR of mRNA from isolated PVECs. EndMT cells had higher proliferative activity and migration activity than mesenchymal cells. All of these changes were alleviated by intraperitoneal injection of vildagliptin. Interestingly, vildagliptin and linagliptin significantly attenuated EndMT in the absence of immune

Anti-inflammatory activity of fisetin in human gingival fibroblasts treated with lipopolysaccharide.

PubMed

Gutiérrez-Venegas, Gloria; Contreras-Sánchez, Anabel; Ventura-Arroyo, Jairo Agustín

2014-10-01

Fisetin is an anti-inflammatory flavonoid; however, its anti-inflammatory mechanism is not yet understood. In this study, we evaluated the anti-inflammatory effect of fisetin and its association with mitogen-activated protein kinase (MAPK) and nuclear factor kappa-beta pathways in human gingival fibroblasts (HGFs) treated with lipopolysaccharide (LPS) obtained from Porphyromonas gingivalis. The cell signaling, cell viability, and cyclooxygenase-2 (COX-2) expression of HGFs treated with various concentrations (0, 1, 5, 10, and 15 μM) of fisetin were measured by cell viability assay (MTT), Western blotting, and reverse transcriptase polymerase chain reaction analysis on COX-2. We found that fisetin significantly reduced the synthesis and expression of prostaglandin E2 in HGFs treated with LPS. Activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 MAPK was suppressed consistently by fisetin in HGFs treated with LPS. The data indicate that fisetin inhibits MAPK activation and COX-2 expression without affecting cell viability. These findings may be valuable for understanding the mechanism of the effect of fisetin on periodontal disease.

Serum antibodies against gangliosides and Campylobacter jejuni lipopolysaccharides in Miller Fisher syndrome.

PubMed Central

Neisser, A; Bernheimer, H; Berger, T; Moran, A P; Schwerer, B

1997-01-01

Seven patients with Miller Fisher syndrome (MFS), six in the acute phase and one in the recovery phase, were investigated for serum antibodies against gangliosides and purified lipopolysaccharides (LPS) from different strains of Campylobacter jejuni, including the MFS-associated serotypes O:2 and O:23. Immunoglobulin G antibodies against gangliosides GT1a and GQ1b were found in five of six patients in the acute phase of disease. Three of these patients also displayed antibodies to ganglioside GD2, a finding not previously reported for MFS. All anti-GT1a- and anti-GQ1b-seropositive patients showed antibody binding to C. jejuni LPS, predominantly to O:2 and O:23 LPS. Antibody cross-reactivity between gangliosides GT1a and GQ1b and O:2 and O:23 LPS was demonstrated by adsorption studies. This cross-reactivity between gangliosides and C.jejuni LPS, which is obviously due to oligosaccharide homologies, may be an important pathogenetic factor in the development of MFS after C. jejuni infection. PMID:9317004

Opposing effects of cationic antimicrobial peptides and divalent cations on bacterial lipopolysaccharides

NASA Astrophysics Data System (ADS)

Smart, Matthew; Rajagopal, Aruna; Liu, Wing-Ki; Ha, Bae-Yeun

2017-10-01

The permeability of the bacterial outer membrane, enclosing Gram-negative bacteria, depends on the interactions of the outer, lipopolysaccharide (LPS) layer, with surrounding ions and molecules. We present a coarse-grained model for describing how cationic amphiphilic molecules (e.g., antimicrobial peptides) interact with and perturb the LPS layer in a biologically relevant medium, containing monovalent and divalent salt ions (e.g., Mg2+). In our approach, peptide binding is driven by electrostatic and hydrophobic interactions and is assumed to expand the LPS layer, eventually priming it for disruption. Our results suggest that in parameter ranges of biological relevance (e.g., at micromolar concentrations) the antimicrobial peptide magainin 2 effectively disrupts the LPS layer, even though it has to compete with Mg2+ for the layer. They also show how the integrity of LPS is restored with an increasing concentration of Mg2+. Using the approach, we make a number of predictions relevant for optimizing peptide parameters against Gram-negative bacteria and for understanding bacterial strategies to develop resistance against cationic peptides.

Increase of heat-shock protein and induction of gamma/delta T cells in peritoneal exudate of mice after injection of live Fusobacterium nucleatum.

PubMed Central

Saito, K; Katsuragi, H; Mikami, M; Kato, C; Miyamaru, M; Nagaso, K

1997-01-01

Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans are Gram-negative rod periodontal pathogens. The peritoneal cavity of Institute of Cancer Research (ICR) mice was used as the local infection model. In vivo production of heat-shock proteins (hsp) was studied by injection of 1/10 minimum lethal dose (MLD) of each live bacteria into mice. Heat-shock proteins 70 and 60 were examined in the extract of peritoneal exudate cells (PEC) from mice injected intraperitoneally with either F. nucleatum or A. actinomycetemcomitans by using sodium dodecylsulphate-polyacrylamide gel electrophoresis and immunoblotting analysis. Although hsp are present in PEC without injection of the bacteria, both hsp increased and reached a peak on day 3 after F. nucleatum injection but not after A. actinomycetemcomitans. Kinetic study of gamma/delta cells in PEC after injection of bacteria showed that the increase of gamma/delta T cells was observed only in the PEC from mice injected with F. nucleatum but not A. actinomycetemcomitans. The gamma/delta T cells in PEC were either CD3+ and CD4+ or CD3+ and CD8+. The differential cell count of PEC suggested that gamma/delta T-cell induction is related to the expansion of the macrophage population. The phagocytic and chemiluminescence responses of macrophages against the same bacteria were compared after intensive immunization with live F. nucleatum and A. actinomycetemcomitans. Elevations of chemiluminescence response and phagocytic function by immunization were observed in the macrophages of mice immunized with F. nucleatum. These results suggest the sequential appearance of hsp, gamma/delta T cells and macrophage activation after fusobacterial infection. Images Figure 2 PMID:9135551

Protective effect of magnolol-loaded polyketal microparticles on lipopolysaccharide-induced acute lung injury in rats.

PubMed

Tsai, Tsuimin; Kao, Chen-Yu; Chou, Chun-Liang; Liu, Lu-Chun; Chou, Tz-Chong

2016-08-01

Magnolol has shown inhibitory effects on NO production and TNF-alpha production in lipopolysaccharide (LPS)-activated macrophages and LPS-induced acute lung injury; however, the poor solubility of magnolol has hindered its clinical success. In this study, magnolol-loaded microparticles were prepared via single emulsion method from a polyketal polymer, termed PK3. The particle sizes of magnolol-loaded PK3 microparticle is 3.73 ± 0.41 μm, and was suitable for phagocytosis by macrophages and pulmonary drug delivery. PK3 microparticles exhibited excellent biocompatibility both in vitro and in vivo. More importantly, intratracheal delivery of these magnolol-loaded microparticles significantly reduced the lung inflammatory responses at low dosage of magnolol (0.5 mg/kg), and have great clinical potential in treating acute lung injury.

Structural and functional features of a developmentally regulated lipopolysaccharide-binding protein.

PubMed

Krasity, Benjamin C; Troll, Joshua V; Lehnert, Erik M; Hackett, Kathleen T; Dillard, Joseph P; Apicella, Michael A; Goldman, William E; Weiss, Jerrold P; McFall-Ngai, Margaret J

2015-10-13

Mammalian lipopolysaccharide (LPS) binding proteins (LBPs) occur mainly in extracellular fluids and promote LPS delivery to specific host cell receptors. The function of LBPs has been studied principally in the context of host defense; the possible role of LBPs in nonpathogenic host-microbe interactions has not been well characterized. Using the Euprymna scolopes-Vibrio fischeri model, we analyzed the structure and function of an LBP family protein, E. scolopes LBP1 (EsLBP1), and provide evidence for its role in triggering a symbiont-induced host developmental program. Previous studies showed that, during initial host colonization, the LPS of V. fischeri synergizes with peptidoglycan (PGN) monomer to induce morphogenesis of epithelial tissues of the host animal. Computationally modeled EsLBP1 shares some but not all structural features of mammalian LBPs that are thought important for LPS binding. Similar to human LBP, recombinant EsLBP1 expressed in insect cells bound V. fischeri LPS and Neisseria meningitidis lipooligosaccharide (LOS) with nanomolar or greater affinity but bound Francisella tularensis LPS only weakly and did not bind PGN monomer. Unlike human LBP, EsLBP1 did not bind N. meningitidis LOS:CD14 complexes. The eslbp1 transcript was upregulated ~22-fold by V. fischeri at 24 h postinoculation. Surprisingly, this upregulation was not induced by exposure to LPS but, rather, to the PGN monomer alone. Hybridization chain reaction-fluorescent in situ hybridization (HCR-FISH) and immunocytochemistry (ICC) localized eslbp1 transcript and protein in crypt epithelia, where V. fischeri induces morphogenesis. The data presented here provide a window into the evolution of LBPs and the scope of their roles in animal symbioses. Mammalian lipopolysaccharide (LPS)-binding protein (LBP) is implicated in conveying LPS to host cells and potentiating its signaling activity. In certain disease states, such as obesity, the overproduction of this protein has been a

Protective effects of melatonin on lipopolysaccharide-induced mastitis in mice.

PubMed

Shao, Guoxi; Tian, Yinggang; Wang, Haiyu; Liu, Fangning; Xie, Guanghong

2015-12-01

Melatonin, a secretory product of the pineal gland, has been reported to have antioxidant and anti-inflammatory effects. However, the protective effects of melatonin on lipopolysaccharide (LPS)-induced mastitis have not been reported. The purpose of this study was to investigate the anti-inflammatory effects and the underlying mechanisms of melatonin on LPS-induced mastitis both in vivo and in vitro. In vivo, our results showed that melatonin attenuated LPS-induced mammary histopathologic changes and myeloperoxidase (MPO) activity. Melatonin also inhibited LPS-induced inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) production in mammary tissues. In vitro, melatonin was found to inhibit LPS-induced TNF-α and IL-6 production in mouse mammary epithelial cells. Melatonin also suppressed LPS-induced Toll-like receptor 4 (TLR4) expression and nuclear factor-kappaB (NF-κB) activation in a dose-dependent manner. In addition, melatonin was found to up-regulate the expression of PPAR-γ. Inhibition of PPAR-γ by GW9662 reduced the anti-inflammatory effects of melatonin. In conclusion, we found that melatonin, for the first time, had protective effects on LPS-induced mastitis in mice. The anti-inflammatory mechanism of melatonin was through activating PPAR-γ which subsequently inhibited LPS-induced inflammatory responses. Copyright © 2015 Elsevier B.V. All rights reserved.

Establishment of hydrochloric acid/lipopolysaccharide-induced pelvic inflammatory disease model

PubMed Central

Oh, Yeonsu; Lee, Jaehun; Kim, Hyeon-Cheol; Hahn, Tae-Wook; Yoon, Byung-Il; Han, Jeong-Hee; Kwon, Yong-Soo; Park, Joung Jun; Koo, Deog-Bon; Rhee, Ki-Jong

2016-01-01

Pelvic inflammatory disease (PID), which is one of the most problematic complications experienced by women with sexually transmitted diseases, frequently causes secondary infections after reproductive abnormalities in veterinary animals. Although the uterus is self-protective, it becomes fragile during periods or pregnancy. To investigate PID, bacteria or lipopolysaccharide (LPS) extracted from gram negative bacteria has been used to induce the disease in several animal models. However, when LPS is applied to the peritoneum, it often causes systemic sepsis leading to death and the PID was not consistently demonstrated. Hydrochloric acid (HCl) has been used to induce inflammation in the lungs and stomach but not tested for reproductive organs. In this study, we developed a PID model in mice by HCl and LPS sequential intracervical (i.c.) administration. The proinflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor-α, were detected in the mouse uterus by western blot analysis and cytokine enzyme-linked immunosorbent assay after HCl (25 mg/kg) administration i.c. followed by four LPS (50 mg/kg) treatments. Moreover, mice exhibited increased infiltration of neutrophils in the endometrium and epithelial layer. These results suggest that ic co-administration of HCl and LPS induces PID in mice. This new model may provide a consistent and reproducible PID model for future research. PMID:26726020