Background: Mfa1 fimbriae of the periodontal pathogen Porphyromonas gingivalis are responsible for biofilm formation and comprise five proteins: Mfa1-5. Two major genotypes, mfa1 and mfa1, encode major fimbrillin. The mfa1 genotype is further divided into the mfa1 and mfa1 subtypes.
View Article and Find Full Text PDFBackground: Sports mouthguards, worn in the oral cavity to prevent sports injuries, are constantly exposed to various microorganisms that cause oral infections. Hence, the optimal cleaning methods for sports mouthguards have been thoroughly examined. In this study, we evaluated the efficiency of cleaning effects with a mouthguard cleaner (MC) on microbial biofilm formation in sports mouthguards and .
View Article and Find Full Text PDFThe effect of Mfa1 fimbriae of on the progression of bone resorption remains unclear, especially compared with another fimbriae, FimA. We investigated the effect of Mfa1 on osteoclastogenesis together with FimA. We also investigated the role of Toll-like receptors (TLRs) in Mfa1 recognition during osteoclast differentiation.
View Article and Find Full Text PDFis an important causative organism of respiratory tract infections. Although periodontal bacteria have been shown to influence respiratory infections such as aspiration pneumonia, the synergistic effect of and , a periodontopathic bacterium, on pneumococcal infections is unclear. To investigate whether accelerates pneumococcal infections, we tested the effects of inoculating culture supernatant (PgSup) into -infected mice.
View Article and Find Full Text PDFMfa1 fimbriae are thought to act as adhesion factors and to direct periodontal tissue destruction but their immunomodulatory actions are poorly understood. Here, we investigated the effect of Mfa1 stimulation on the immune and metabolic mechanisms of gingival fibroblasts from periodontal connective tissue. We also determined the role of Toll-like receptor (TLR) 2 and TLR4 in Mfa1 recognition.
View Article and Find Full Text PDFSendai virus V protein is a known antagonist of RIG-I-like receptors (RLRs) RIG-I and MDA5, which activate transcription factors IRF3, leading to activation of ISGF3 and NF-κB. These transcription factors are known activators of inducible NO synthase (iNOS) and increase the production of nitric oxide (NO). By inhibiting ISGF3 and NF-κB, the V protein acts as an indirect negative regulator of iNOS and NO.
View Article and Find Full Text PDFPM2.5 is a particle with a diameter <2.5 µm that is often involved in air pollution.
View Article and Find Full Text PDFTo suppress virus multiplication, infected macrophages produce NO. However, it remains unclear how infecting viruses then overcome NO challenge. In the present study, we report the effects of accessory protein C from Sendai virus (SeV), a prototypical paramyxovirus, on NO output.
View Article and Find Full Text PDFInflammasomes play a key role in host innate immune responses to viral infection by caspase-1 (Casp-1) activation to facilitate interleukin-1β (IL-1β) secretion, which contributes to the host antiviral defense. The NLRP3 inflammasome consists of the cytoplasmic sensor molecule NLRP3, adaptor protein ASC, and effector protein pro-caspase-1 (pro-Casp-1). NLRP3 and ASC promote pro-Casp-1 cleavage, leading to IL-1β maturation and secretion.
View Article and Find Full Text PDFA Wnt agonist, 2-amino-4-[3,4-(methylenedioxy)benzylamino]-6-(3-methoxyphenyl) pyrimidine, is a cell-permeable pyrimidine compound that has been shown to mimic the effect of Wnt. In this study, leukemic mouse cell lines, RAW 264.7 and J774.
View Article and Find Full Text PDFIL-1β is one of the inflammatory cytokines and is cleaved from pro-IL-1β proteolytically by activated Caspase 1. For the activation of Caspase 1, inflammasome was formed by two signals, what is called, priming and triggering signals. In this study, it was found that mouse macrophage J774.
View Article and Find Full Text PDFIt has been known that LPS activates macrophages and induces IFN-β production from macrophages. The endogenous IFN-β produced by LPS stimulates the cells, which plays a role in innate immune. However, it was not elucidated yet if the signaling by exogenous IFN-β was influenced by LPS stimulation.
View Article and Find Full Text PDFThe effect of TGF-β1 on CpG DNA-induced type I IFN production was examined by reconstituting a series of signaling molecules in TLR 3 signaling. TGF-β1 inhibited CpG DNA-induced IFN-α4 productivity in HeLa cells. Transfection of IFN regulatory factor (IRF)7 but not TNF receptor-associated factor (TRAF)6 and TRAF3 into cells triggered IFN-α4 productivity, and TGF-β1 inhibited IRF7-mediated type I IFN production in the presence of TRAF6.
View Article and Find Full Text PDFThe effect of Sendai virus (SeV) C protein on lipopolysaccharide (LPS)-induced nitric oxide (NO) production was examined using RAW 264.7 macrophage cells. Infection of SeV inhibited LPS-induced NO production via downregulating the expression of an inducible NO synthase protein (iNOS).
View Article and Find Full Text PDFThe effect of lipopolysaccharide (LPS) on the expression of p53 protein in RAW 264.7 macrophage cells was examined. LPS downregulated the expression of p53 protein 4-24 h after the stimulation.
View Article and Find Full Text PDFThe inhibitory effect of valproic acid (VPA) on lipopolysaccharide (LPS)-induced inflammatory response was studied by using mouse RAW 264.7 macrophage-like cells. VPA pretreatment attenuated LPS-induced phosphorylation of phosphatidylinositol 3-kinase (PI3K) and Akt, but not nuclear factor (NF)-κB and mitogen-activated protein kinases.
View Article and Find Full Text PDFHere we report that LPS induces osteoclast (OC) formation in murine RAW 264.7 macrophage cells in RPMI-1640 medium but not in α-minimum essential medium (α-MEM) as the original culture medium. LPS-induced OC formation in both media was examined to clarify the differential response.
View Article and Find Full Text PDFThe effect of lipopolysaccharide (LPS) on insulin sensitivity in adipocytes were examined by using differentiated 3T3-L1 adipocytes. Insulin-mediated activation of insulin receptor substrate (IRS) 1/2 was inhibited in LPS-pretreated adipocytes and IRS1/2-mediated Akt activation was also attenuated in those cells. LPS inhibited activation of glycogen synthase kinase 3 as a negative regulator of glycogenesis and impaired the glycogen synthesis in response to insulin.
View Article and Find Full Text PDFA toll-like receptor 4 (TLR-4) ligand, lipopolysaccharide (LPS) not only activates expression and secretion of inflammatory cytokines, but it also often shows toxicity in monocytes. Whether an oncogenic protein, β-catenin, is positively involved in LPS-induced cytotoxicity in a mouse leukemic monocyte cell line, RAW 264.7, was examined.
View Article and Find Full Text PDFThe effect of LPS on the production of vascular endothelial growth factor (VEGF) was examined using RAW 264.7 macrophage cells. LPS induced VEGF production in RAW 264.
View Article and Find Full Text PDFThe effect of Pam3CSK4, a Toll-like receptor 2 (TLR2) ligand, on interferon-γ (IFN-γ) -induced nitric oxide (NO) production in mouse vascular endothelial END-D cells was studied. Pre-treatment or post-treatment with Pam3CSK4 augmented IFN-γ-induced NO production via enhanced expression of an inducible NO synthase (iNOS) protein and mRNA. Pam3CSK4 augmented phosphorylation of Janus kinase 1 and 2, followed by enhanced phosphorylation of signal transducer and activator of transcription 1 (STAT1) at tyrosine 701.
View Article and Find Full Text PDFThe effect of lipopolysaccharide (LPS) on valproic acid (VPA)-induced cell death was examined by using mouse RAW 264.7 macrophage cells. LPS inhibited the activation of caspase 3 and poly (ADP-ribose) polymerase and prevented VPA-induced apoptosis.
View Article and Find Full Text PDFThe pyrin and HIN-domain (PYHIN) family member1 (pyhin1) is a member of PYHIN proteins and involved in transcriptional regulation of genes important for cell cycle control, differentiation and apoptosis. The regulatory action of mouse pyhin1 on LPS-induced inflammatory response was examined. LPS augmented the pyhin1 mRNA expression in murine RAW 264.
View Article and Find Full Text PDFThe effect of pyrroloquinoline quinine (PQQ) on receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast formation was examined using RAW 264.7 macrophage-like cells. RANKL led to the formation of osteoclasts identified as tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells in the culture of RAW 264.
View Article and Find Full Text PDFAn ADP ribosylation factor-GTPase activating protein (ASAP1) is highly expressed in a variety of tumor cells and is involved in the cell motility, invasion, and metastasis. In order to elucidate the involvement of ASAP1 in lipopolysaccharide (LPS)-mediated inflammatory response, the effect of ASAP1 silencing on LPS-induced proinflammatory mediators production was examined by using RAW 264.7 macrophage-like cells.
View Article and Find Full Text PDF