Alendronate Augments Lipid A-Induced IL-1α Release via Activation of ASC but Not Caspase-11.

Nitrogen-containing bisphosphonates (NBPs), such as alendronate (ALN), are anti-bone-resorptive drugs that have inflammatory side effects. We previously reported that ALN augmented lipid A-induced interleukin (IL)-1ß production and NOD-like receptor pyrin domain-containing-3 (NLRP3)/apoptosis-associated speck-like protein containing a CARD (ASC)-dependent cell death. The present study aimed to examine whether ALN augments lipid A-induced IL-1α release and necroptosis, which is induced by the activation of receptor-interacting protein kinase (RIPK) 3. Treatment of J774.1 cells with ALN augmented lipid A-induced IL-1α release, which was not inhibited by Ac-IETD-CHO, a caspase-8 inhibitor. ALN also activated mixed lineage kinase domain-like (MLKL), a key mediator of the necroptosis pathway, and upregulated the expression of caspase-11, a lipid A receptor. GSK'872, a RIPK3 inhibitor, suppressed the ALN-upregulated expression of caspase-11 and augmented lipid A-induced caspase-8 activation. Moreover, ALN induced the release of NLRP3 and ASC into culture supernatants. GSK'872, but not Ac-IETD-CHO, reduced the ALN-induced release of NLRP3, but not ASC, into culture supernatants, and reduced ALN-induced cell death, but not ALN-induced LDH release. Antibodies against NLRP3 and ASC upregulated caspase-11 expression in the cytosol by inhibiting ALN-induced cell death. However, pretreating cells with an antibody against ASC, but not NLRP3, before ALN addition also inhibited lipid A-induced IL-1α release. Pretreating cells with an antibody against caspase-11 before the addition of ALN or lipid A did not downregulate lipid A-induced production of IL-1α. Taken together, our findings suggest that ALN augments lipid A-induced IL-1α release via activation of ASC, but not caspase-11.

MPMBP down-regulates Toll-like receptor (TLR) 2 ligand-induced proinflammatory cytokine production by inhibiting NF-κB but not AP-1 activation.

MPMBP is a novel non-nitrogen-containing bisphosphonate (non-NBP) which possesses anti-bone resorptive activity and an antioxidant side chain. This study aimed to assess the effects of MPMBP on the production of proinflammatory cytokines and chemokines by the macrophage-like cell line, J774.1, in the presence of Toll-like receptor (TLR) agonists. J774.1 cells were pretreated with or without MPMBP for 5 min, and then incubated with or without Pam3Cys-Ser-(Lys)4 (Pam3CSK4, a TLR2 agonist) or lipid A (a TLR4 agonist) for 24 h. MPMBP down-regulated TLR2 ligand-induced production of IL-6, MCP-1, MIP-1α, and TNF-α, but not TLR4 ligand-induced proinflammatory cytokine production, and was not cytotoxic in J774.1 cells. Cu-CPT22, a TLR2 antagonist, down-regulated Pam3CSK4-induced production of IL-6, MCP-1, and MIP-1α, but not TNF-α. MPMBP inhibited the translocation of NF-κB p65, but not p50, RelB, or p52, and inhibited the activation of JNK, but not p38 MAPK or ERK, in J774.1 cells stimulated with Pam3CSK4. Moreover, MPMBP did not down-regulate AP-1 activation in J774.1 cells stimulated with Pam3CSK4 or lipid A. Our findings suggest that MPMBP inhibits proinflammatory cytokine production in J774.1 cells by suppressing NF-κB p65 activation in the TLR2, but not TLR4, pathway.

Effects of chemical treatment as an adjunctive of air-abrasive debridement on restoring the surface chemical properties and cytocompatibility of experimentally contaminated titanium surfaces.

The aim of this study was to evaluate the effects of three different chemotherapeutic agents, following air-abrasive debridement, on surface chemical properties and cytocompatibility. Disks contaminated with Streptococcus gordonii biofilm were treated with air-abrasion and immersion in either 0.9% NaCl (Air + NaCl), 0.05% alkaline electrolyzed water (AEW) (Air + AEW), or 3% H2 O2 (Air + H2 O2 ). Noncontaminated and untreated titanium disks served as a control (As-polished). The efficacy of biofilm removal, magnitude of initial cytocompatibility toward human bone marrow mesenchymal stem cells, and surface chemical properties were determined. In all treatment groups, biofilms containing microorganisms were observed to be completely removed. The data showed discrepancies for cell affinities among treatment groups, whereby: (1) the number of cells attached to the Air + AEW treated surfaces was approximately two times greater than that to the Air + NaCl treated surfaces; and (2) cell spreading was significantly enhanced on the Air + AEW treated surfaces compared with the Air + NaCl or Air + H2 O2 treated surfaces. X-ray photoelectron spectroscopy data showed that the mean relative concentrations of nitrogen to titanium on the As-polished, Air + NaCl, Air + AEW, and Air + H2 O2 surfaces were 0.0079, 0.0237, 0.0071, and 0.0210, respectively, which would provide a clear understanding that these discrepancies could be attributed to sufficient removals of organic-nitrogen deposits at the same magnitude as the As-polished following the Air + AEW treatment. This study clarifies that chemical surface treatment with AEW, as an adjunctive to air-abrasive debridement may be beneficial in restoring surface properties for tissue integration. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:183-191, 2020.

Draft Genome Sequences of Two Veillonella tobetsuensis Clinical Isolates from Intraoperative Bronchial Fluids of Elderly Patients with Pulmonary Carcinoma.

To date, Veillonella tobetsuensis has been known as an oral anaerobe and a facilitator of early-stage oral biofilm development with streptococci. Here, we report the draft genome sequences of 2 strains of V. tobetsuensis first isolated from intraoperative bronchial fluids of elderly patients with pulmonary carcinoma.

Identification of Veillonella Species in the Tongue Biofilm by Using a Novel One-Step Polymerase Chain Reaction Method.

Six Veillonella species have been frequently isolated from human oral cavities including infectious sites. Recently, it was reported that diet, smoking, and possibly socioeconomic status can influence the bacterial profile in oral cavities. In addition, oral hygiene habits may also influence oral microbiota in terms of both numbers and diversity of microorganisms. In this study, the identification of Veillonella species in tongue biofilms of Thai children, divided into three groups dependent on their status of oral hygiene. For this, we used a novel one-step PCR method with species-specific primer sets based on sequences of the rpoB gene. As shown in the results, the number of isolates of Veillonella species was 101 strains from only 10 of 89 subjects. However, the total number of bacteria was high for all subjects. Since it was reported in previous studies that Veillonella species were easy to isolate in human tongue biofilms at high numbers, the results obtained in this study may suggest country- or age-specific differences. Moreover, Veillonella species were detected predominantly in subjects who had poor oral hygiene compared to those with good or moderate oral hygiene. From these results, there is a possibility that Veillonella species may be an index of oral hygiene status. Furthermore, V. rogosae was a predominant species in tongue biofilms of Thai children, whereas V. parvula and V. denticariosi were not isolated at all. These characteristics of the distribution and frequency of Veillonella species are similar to those reported in previous studies. Although further studies are needed in other countries, in this study, a successful novel one-step PCR method was established to detect Veillonella species in human oral cavities easily and effectively. Furthermore, this is the first report investigating the distribution and frequency of Veillonella species in tongue biofilms of Thai children.