Therapeutic Effects of Inhibitor of ompA Expression against Carbapenem-Resistant Acinetobacter baumannii Strains

The widespread of carbapenem-resistant Acinetobacter baumannii (CRAB) is of great concern in clinical settings worldwide. It is urgent to develop new therapeutic agents against this pathogen. This study aimed to evaluate the therapeutic potentials of compound 62520, which has been previously identified as an inhibitor of the ompA promoter activity of A. baumannii, against CRAB isolates, both in vitro and in vivo. Compound 62520 was found to inhibit the ompA expression and biofilm formation in A. baumannii ATCC 17978 at sub-inhibitory concentrations in a dose-dependent manner. These inhibitory properties were also observed in clinical CRAB isolates belonging to sequence type (ST) 191. Additionally, compound 62520 exhibited a bacteriostatic activity against clinical clonal complex (CC) 208 CRAB isolates, including ST191, and ESKAPE pathogens. This bacteriostatic activity was not different between STs of CRAB isolates. Bacterial clearance was observed in mice infected with bioimaging A. baumannii strain 24 h after treatment with compound 62520. Compound 62520 was shown to significantly increase the survival rates of both immunocompetent and neutropenic mice infected with A. baumannii ATCC 17978. This compound also increased the survival rates of mice infected with clinical CRAB isolate. These results suggest that compound 62520 is a promising scaffold to develop a novel therapeutic agent against CRAB infections.

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Tolerogenic Splenic IDO+Dendritic Cells from the Mice Treated with Induced-Treg Cells Suppress Collagen-Induced Arthritis

Journal of Immunology Research ◽

10.1155/2014/831054 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12 ◽

Cited By ~ 9

Author(s):

Jie Yang ◽

Yiming Yang ◽

Huahua Fan ◽

Hejian Zou

Keyword(s):

Dendritic Cells ◽

Immune Responses ◽

Foxp3 Expression ◽

Treated Group ◽

Treg Cells ◽

Therapeutic Effects ◽

Dependent Manner ◽

Collagen Induced Arthritis

TGF-β-induced regulatory T cells (iTregs) retain Foxp3 expression and immune-suppressive activity in collagen-induced arthritis (CIA). However, the mechanisms whereby transferred iTregs suppress immune responses, particularly the interplay between iTregs and dendritic cells (DCs)in vivo, remain incompletely understood. In this study, we found that after treatment with iTregs, splenic CD11c+DCs, termed “DCiTreg,” expressed tolerogenic phenotypes, secreted high levels of IL-10, TGF-β, and IDO, and showed potent immunosuppressive activityin vitro. After reinfusion with DCiTreg, marked antiarthritic activity improved clinical scores and histological end-points were observed. The serological levels of inflammatory cytokines and anti-CII antibodies were low and TGF-βproduction was high in the DCiTreg-treated group. DCiTregalso induced new iTregsin vivo. Moreover, the inhibitory activity of DCiTregon CIA was lost following pretreatment with the inhibitor of indoleamine 2,3-dioxygenase (IDO). Collectively, these findings suggest that transferred iTregs could induce tolerogenic characteristics in splenic DCs and these cells could effectively dampen CIA in an IDO-dependent manner. Thus, the potential therapeutic effects of iTregs in CIA are likely maintained through the generation of tolerogenic DCsin vivo.

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Immunomodulatory Effects of Adipose Tissue-Derived Stem Cells on Concanavalin A-Induced Acute Liver Injury in Mice

Cell Medicine ◽

10.3727/215517916x693159 ◽

2017 ◽

Vol 9 (1-2) ◽

pp. 21-33 ◽

Cited By ~ 10

Author(s):

Yasuma Yoshizumi ◽

Hiroshi Yukawa ◽

Ryoji Iwaki ◽

Sanae Fujinaka ◽

Ayano Kanou ◽

...

Keyword(s):

Stem Cells ◽

Adipose Tissue ◽

Mouse Model ◽

Cell Therapy ◽

Concanavalin A ◽

Therapeutic Effects ◽

Dependent Manner ◽

Immunomodulatory Effects

Cell therapy with adipose tissue-derived stem cells (ASCs) is expected to be a candidate for the treatment of fulminant hepatic failure (FHF), which is caused by excessive immune responses. In order to evaluate the therapeutic effects of ASCs on FHF, the in vitro and in vivo immunomodulatory effects of ASCs were examined in detail in the mouse model. The in vitro effects of ASCs were examined by assessing their influence on the proliferation of lymphomononuclear cells (LMCs) stimulated with three kinds of mitogens: phorbol 12-myristate 13-acetate (PMA) plus ionomycin, concanavalin A (ConA), and lipopolysaccharide (LPS). The proliferation of LMCs was efficiently suppressed in a dose-dependent manner by ASCs in the cases of PMA plus ionomycin stimulation and ConA stimulation, but not in the case of LPS stimulation. The in vivo effects of transplanted ASCs were examined in the murine FHF model induced by ConA administration. The ALT levels and histological inflammatory changes in the ConA-administered mice were apparently relieved by the transplantation of ASCs. The analysis of mRNA expression patterns in the livers indicated that the expressions of the cytokines such as Il-6, Il-10, Ifn-γ, and Tnf-α, and the cell surface markers such as Cd3γ, Cd4, Cd8α, Cd11b, and Cd11c were downregulated in the ASC-transplanted mice. The immunomodulatory and therapeutic effects of ASCs were confirmed in the mouse model both in vitro and in vivo. These suggest that the cell therapy with ASCs is beneficial for the treatment of FHF.

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In Vitro and In Vivo Activity of AS101 against Carbapenem-Resistant Acinetobacter baumannii

Pharmaceuticals ◽

10.3390/ph14080823 ◽

2021 ◽

Vol 14 (8) ◽

pp. 823

Author(s):

Tsung-Ying Yang ◽

Sung-Pin Tseng ◽

Heather Nokulunga Dlamini ◽

Po-Liang Lu ◽

Lin Lin ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Antibacterial Activities ◽

Treated Group ◽

Infection Model ◽

High Dose ◽

Mouse Infection Model ◽

Carbapenem Resistant ◽

Time Kill

The increasing trend of carbapenem-resistant Acinetobacter baumannii (CRAB) worldwide has become a concern, limiting therapeutic alternatives and increasing morbidity and mortality rates. The immunomodulation agent ammonium trichloro (dioxoethylene-O,O′-) tellurate (AS101) was repurposed as an antimicrobial agent against CRAB. Between 2016 and 2018, 27 CRAB clinical isolates were collected in Taiwan. The in vitro antibacterial activities of AS101 were evaluated using broth microdilution, time-kill assay, reactive oxygen species (ROS) detection and electron microscopy. In vivo effectiveness was assessed using a sepsis mouse infection model. The MIC range of AS101 for 27 CRAB isolates was from 0.5 to 32 µg/mL, which is below its 50% cytotoxicity (approximately 150 µg/mL). Bactericidal activity was confirmed using a time-kill assay. The antibacterial mechanism of AS101 was the accumulation of the ROS and the disruption of the cell membrane, which, in turn, results in cell death. The carbapenemase-producing A. baumannii mouse sepsis model showed that AS101 was a better therapeutic effect than colistin. The mice survival rate after 120 h was 33% (4/12) in the colistin-treated group and 58% (7/12) in the high-dose AS101 (3.33 mg/kg/day) group. Furthermore, high-dose AS101 significantly decreased bacterial population in the liver, kidney and spleen (all p < 0.001). These findings support the concept that AS101 is an ideal candidate for further testing in future studies.

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Capsule carbohydrate structure determines virulence in Acinetobacter baumannii

PLoS Pathogens ◽

10.1371/journal.ppat.1009291 ◽

2021 ◽

Vol 17 (2) ◽

pp. e1009291

Author(s):

Yuli Talyansky ◽

Travis B. Nielsen ◽

Jun Yan ◽

Ulrike Carlino-Macdonald ◽

Gisela Di Venanzio ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Bacterial Pathogen ◽

Specific Gene ◽

Dependent Manner ◽

Bacterial Burden ◽

Carbohydrate Structure ◽

Loss Of Function ◽

Capsule Assembly

Acinetobacter baumannii is a highly antibiotic-resistant bacterial pathogen for which novel therapeutic approaches are needed. Unfortunately, the drivers of virulence in A. baumannii remain uncertain. By comparing genomes among a panel of A. baumannii strains we identified a specific gene variation in the capsule locus that correlated with altered virulence. While less virulent strains possessed the intact gene gtr6, a hypervirulent clinical isolate contained a spontaneous transposon insertion in the same gene, resulting in the loss of a branchpoint in capsular carbohydrate structure. By constructing isogenic gtr6 mutants, we confirmed that gtr6-disrupted strains were protected from phagocytosis in vitro and displayed higher bacterial burden and lethality in vivo. Gtr6+ strains were phagocytized more readily and caused lower bacterial burden and no clinical illness in vivo. We found that the CR3 receptor mediated phagocytosis of gtr6+, but not gtr6-, strains in a complement-dependent manner. Furthermore, hypovirulent gtr6+ strains demonstrated increased virulence in vivo when CR3 function was abrogated. In summary, loss-of-function in a single capsule assembly gene dramatically altered virulence by inhibiting complement deposition and recognition by phagocytes across multiple A. baumannii strains. Thus, capsular structure can determine virulence among A. baumannii strains by altering bacterial interactions with host complement-mediated opsonophagocytosis.

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Efficacy of adavosertib therapy against anaplastic thyroid cancer

Endocrine Related Cancer ◽

10.1530/erc-21-0001 ◽

2021 ◽

Author(s):

Yu-Ling Lu ◽

Yu-Tung Huang ◽

Ming-Hsien Wu ◽

Ting-Chao Chou ◽

Richard J Wong ◽

...

Keyword(s):

Thyroid Cancer ◽

Tumor Growth ◽

Single Agent ◽

Xenograft Model ◽

Anaplastic Thyroid Cancer ◽

Therapeutic Effects ◽

Dependent Manner ◽

Cancer Tumor

Wee1 is a kinase that regulates the G2/M progression by inhibition of CDK1, which is critical for ensuring DNA damage repair before initiation of mitotic entry. Targeting Wee1 may be a potential strategy in the treatment of anaplastic thyroid cancer, a rare but lethal disease. The therapeutic effects of adavosertib, a Wee1 inhibitor for anaplastic thyroid cancer was evaluated in this study. Adavosertib inhibited cell growth in three anaplastic thyroid cancer cell lines in a dose-dependent manner. Cell cycle analysis revealed cells were accumulated in the G2/M phase. Adavosertib induced caspase-3 activity and led to apoptosis. Adavosertib monotherapy showed significant retardation of the growth of two anaplastic thyroid cancer tumor models. The combination of adavosertib with dabrafenib and trametinib revealed strong synergism in vitro and demonstrated robust suppression of tumor growth in vivo in anaplastic thyroid cancer xenograft models with BRAFV600E mutation. The combination of adavosertib with either sorafenib or lenvatinib also demonstrated synergism in vitro and had strong inhibition of tumor growth in vivo in an anaplastic thyroid cancer xenograft model. No appreciable toxicity appeared in mice treated with either single agent or combination treatment. Our findings suggest adavosertib holds the promise for the treatment of patients with anaplastic thyroid cancer.

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Radioprotective Effect of Grape Seed Proanthocyanidins In Vitro and In Vivo

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/5706751 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Yijuan Huang ◽

Hainan Zhao ◽

Kun Cao ◽

Ding Sun ◽

Yanyong Yang ◽

...

Keyword(s):

Ionizing Radiation ◽

White Blood Cells ◽

Survival Rates ◽

Grape Seed ◽

Dependent Manner ◽

Grape Seed Proanthocyanidins ◽

Speed Up ◽

Dna Strand

We have demonstrated that grape seed proanthocyanidins (GSPs) could effectively scavenge hydroxyl radical (•OH) in a dose-dependent manner. Since most of the ionizing radiation- (IR-) induced injuries were caused by•OH, this study was to investigate whether GSPs would mitigate IR-induced injuries in vitro and in vivo. We demonstrated that GSPs could significantly reduce IR-induced DNA strand breaks (DSBs) and apoptosis of human lymphocyte AHH-1 cells. This study also showed that GSPs could protect white blood cells (WBC) from IR-induced injuries, speed up the weight of mice back, and decrease plasma malondialdehyde (MDA), thus improving the survival rates of mice after ionizing radiation. It is suggested that GSPs have a potential as an effective and safe radioprotective agent.

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Safety and Efficacy of a Phage, kpssk3, in an in vivo Model of Carbapenem-Resistant Hypermucoviscous Klebsiella pneumoniae Bacteremia

Frontiers in Microbiology ◽

10.3389/fmicb.2021.613356 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yunlong Shi ◽

Yuan Peng ◽

Yixin Zhang ◽

Yu Chen ◽

Cheng Zhang ◽

...

Keyword(s):

Klebsiella Pneumoniae ◽

Gut Microbiota ◽

Mammalian Cells ◽

Phage Therapy ◽

In Vivo Model ◽

Therapeutic Effects ◽

Global Public Health ◽

Carbapenem Resistant

Antimicrobial resistance (AMR) is one of the most significant threats to global public health. As antibiotic failure is increasing, phages are gradually becoming important agents in the post-antibiotic era. In this study, the therapeutic effects and safety of kpssk3, a previously isolated phage infecting carbapenem-resistant hypermucoviscous Klebsiella pneumoniae (CR-HMKP), were evaluated in a mouse model of systemic CR-HMKP infection. The therapeutic efficacy experiment showed that intraperitoneal injection with a single dose of phage kpssk3 (1 × 107 PFU/mouse) 3 h post infection protected 100% of BALB/c mice against bacteremia induced by intraperitoneal challenge with a 2 × LD100 dose of NY03, a CR-HMKP clinical isolate. In addition, mice were treated with antibiotics from three classes (polymyxin B, tigecycline, and ceftazidime/avibactam plus aztreonam), and the 7 days survival rates of the treated mice were 20, 20, and 90%, respectively. The safety test consisted of 2 parts: determining the cytotoxicity of kpssk3 and evaluating the short- and long-term impacts of phage therapy on the mouse gut microbiota. Phage kpssk3 was shown to not be cytotoxic to mammalian cells in vitro or in vivo. Fecal samples were collected from the phage-treated mice at 3 time points before (0 day) and after (3 and 10 days) phage therapy to study the change in the gut microbiome via high-throughput 16S rDNA sequence analysis, which revealed no notable alterations in the gut microbiota except for decreases in the Chao1 and ACE indexes.

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In vitro and in vivo Activity of Combinations of Polymyxin B with Other Antimicrobials Against Carbapenem-Resistant Acinetobacter baumannii

Infection and Drug Resistance ◽

10.2147/idr.s334200 ◽

2021 ◽

Vol Volume 14 ◽

pp. 4657-4666

Author(s):

Hui Zhang ◽

Yunzhu Zhu ◽

Ning Yang ◽

Qinxiang Kong ◽

Yahong Zheng ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Polymyxin B ◽

Carbapenem Resistant

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3BDO Inhibits proliferation, epithelial–mesenchymal transition (EMT) and stemness via suppressing survivin in human glioblastoma cells

10.21203/rs.3.rs-179269/v1 ◽

2021 ◽

Author(s):

zhaotao wang ◽

yongping Li ◽

minyi liu ◽

danmin chen ◽

yunxiang ji ◽

...

Keyword(s):

Cell Proliferation ◽

Mouse Model ◽

Molecular Mechanisms ◽

Migration And Invasion ◽

Therapeutic Effects ◽

Dependent Manner ◽

Mesenchymal Transition ◽

Xenograft Mouse Model

Abstract BackgroundGlioblastoma (GBM) is a tumor of the central nervous system carries an extremely poor prognosis. Unfortunately, it also is the most frequently encountered tumor in this region. These tumors arise from glioblastoma stem cells (GSCs), which are glioma cells that are known to possess high degrees of stemness. GBM invades through the process of EMT, which features loss of cell differentiation and polarity. Survivin is a type of apoptotic inhibitor that has been characterized in several malignancies such as glioma. Normal tissues rarely express survivin. On the other hand, 3-benzyl-5-((2-nitrophenoxy) methyl) dihydrofuran-2(3H)-one (3BDO) represents an autophagy inhibitor and activates the mTOR pathway. It has been reported that 3BDO shows anti-cancer activities in lung carcinoma. However, the effects of 3BDO on GBM reminds unknown. Therefore, the purpose of this study was to explore the role and molecular mechanisms that 3BDO mediates in GBM.MethodCCK-8 experiments and clone formation assay were performed to detect the cell proliferation. Transwell assay was conducted to examined cell migration and invasion. Western blotting and immunofluorescence staining was used to analyze protein expression levels. Xenograft mouse model was used to evaluate the effect of 3BDO in vivo.ResultsWe found that 3BDO inhibited U87 and U251 cell proliferation in a dose-dependent manner. Additonally, 3BDO decreased the sphere formation and stemness markers (sox2, nestin and CD133) in GSCs. 3BDO also inhibited migration, invasion and suppressed EMT markers (N-cadherin, vimentin and snail) in GBM cells. Moreover, we found that 3BDO downregulated survivin expression of survivin both in GBM cells (U87, U251) and GSCs. Furthermore, overexpression of survivin reduced the therapeutic effects of 3BDO on GBM cell EMT, invasion, migration and proliferation, as well as decreased stemness in GSCs. Finally, we demonstrated that 3BDO inhibited tumor growth in a tumor xenograft mouse model constructed using U87 cells. Similar to the in vitro findings, 3BDO diminished suvivin expression, stemness and levels of EMT makers in vivo.Conclusionsour results demonstrated that 3BDO repressed GBM via downregulating survivin-mediated stemness and EMT both in vitro and in vivo.

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