scholarly journals The Bacillus Virulome in Endophthalmitis

2020 ◽  
Author(s):  
Phillip S. Coburn ◽  
Frederick C. Miller ◽  
Morgan A. Enty ◽  
Craig Land ◽  
Austin L. LaGrow ◽  
...  
Keyword(s):  
Murine Model ◽  
Manganese Superoxide Dismutase ◽  
Current Treatment ◽  
Treatment Modalities ◽  
Rna Seq ◽  
Expression Of Genes ◽  
Manganese Superoxide ◽  
New Treatment

AbstractBacillus cereus is recognized as a causative agent of gastrointestinal syndromes, but can also cause a devastating form of intraocular infection known as endophthalmitis. We have previously reported that the PlcR/PapR master virulence factor regulator system regulates intraocular virulence, and that the S-layer protein (SlpA) contributes to the severity of B. cereus endophthalmitis. To begin to better understand the role of other B. cereus virulence genes in endophthalmitis, expression levels of a subset of factors was measured at the midpoint of disease progression in a murine model of experimental endophthalmitis by RNA-Seq. Several cytolytic toxins were expressed at significantly higher levels in vivo than in BHI. The virulence regulators codY, gntR, and nprR were also expressed in vivo. However, at this timepoint, plcR/papR was not detectable, we previously reported that a B. cereus mutant deficient in PlcR was attenuated in the eye. The motility-related genes fla, fliF, and motB, and the chemotaxis-related gene cheA were detected during infection. We have shown previously that motility and chemotaxis phenotypes are important in B. cereus endophthalmitis. The sodA2 variant of manganese superoxide dismutase was the most highly expression gene in vivo, suggesting that this gene is criticial for intraocular survival, potentially through inhibition of neutrophil activity. Expression of the surface layer protein gene, slpA, an activator of Toll-like receptors (TLR) −2 and −4, and a potent contributor to intraocular inflammation and disease severvity, was also detected during infection, albeit at low levels. In summary, genes expressed in a mouse model of Bacillus endophthalmitis might prove to play crucial roles in the unique virulence of B. cereus endophthalmitis, and serve as candidates for novel therapies designed attenuate the severity of this often blinding infection.Impact statementB. cereus causes a potent and rapid infection of the eye that usually results in blindness or enucleation, even with the utilization of current treatment modalities. This necessitates the development of new treatment modalities based on new targets. To begin to better define those B. cereus factors with roles in intraocular infection, we analyzed the expression of genes with both known and hypothesized roles in intraocular infection at the midpoint of infection using a murine model of Bacillus endophthalmitis. Potentially targetable candidate genes were demonstrated to be expressed in vivo, which suggests that these genes might contribute to the unique virulence of B. cereus endophthalmitis. Importantly, our results begin to define the virulome of B. cereus in intraocular infections and identify previously uncharacterized factors with potential roles in the severity and outcome of Bacillus endophthalmitis.

scholarly journals The Bacillus virulome in endophthalmitis

Microbiology ◽  
2021 ◽  
Vol 167 (5) ◽  
Author(s):  
Phillip S. Coburn ◽  
Frederick C. Miller ◽  
Morgan A. Enty ◽  
Craig Land ◽  
Austin L. LaGrow ◽  
...  
Keyword(s):  
Type Species ◽  
Manganese Superoxide Dismutase ◽  
Protein Gene ◽  
Rna Seq ◽  
Content Type ◽  
Link Type ◽  
Manganese Superoxide ◽  
Low Levels

Bacillus cereus is recognized as a causative agent of gastrointestinal syndromes, but can also cause a devastating form of intraocular infection known as endophthalmitis. We have previously reported that the PlcR/PapR master virulence factor regulator system regulates intraocular virulence, and that the S-layer protein (SlpA) contributes to the severity of B. cereus endophthalmitis. To better understand the role of other B. cereus virulence genes in endophthalmitis, expression of a subset of factors was measured at the midpoint of disease progression in a murine model of endophthalmitis by RNA-Seq. Several cytolytic toxins were expressed at significantly higher levels in vivo than in BHI. The virulence regulators codY, gntR, and nprR were also expressed in vivo. However, at this timepoint, plcR/papR was not detectable, although we previously reported that a B. cereus mutant deficient in PlcR was attenuated in the eye. The motility-related genes fla, fliF, and motB, and the chemotaxis-related gene cheA were detected during infection. We have shown previously that motility and chemotaxis phenotypes are important in B. cereus endophthalmitis. The sodA2 variant of manganese superoxide dismutase was the most highly expressed gene in vivo. Expression of the surface layer protein gene, slpA, an activator of Toll-like receptors (TLR)−2 and −4, was also detected during infection, albeit at low levels. Genes expressed in a mouse model of Bacillus endophthalmitis might play crucial roles in the unique virulence of B. cereus endophthalmitis, and serve as candidates for novel therapies designed to attenuate the severity of this often blinding infection.

scholarly journals Inhibitory Effects of a Reengineered Anthrax Toxin on Canine Oral Mucosal Melanomas

Toxins ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 157 ◽  
Author(s):  
Adriana Tomoko Nishiya ◽  
Marcia Kazumi Nagamine ◽  
Ivone Izabel Mackowiak da Fonseca ◽  
Andrea Caringi Miraldo ◽  
Nayra Villar Scattone ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Evaluation Criteria ◽  
Anthrax Toxin ◽  
Treatment Modalities ◽  
Inhibitory Effects ◽  
Upa Receptor ◽  
New Treatment ◽  
Oral Malignancy

Canine oral mucosal melanomas (OMM) are the most common oral malignancy in dogs and few treatments are available. Thus, new treatment modalities are needed for this disease. Bacillus anthracis (anthrax) toxin has been reengineered to target tumor cells that express urokinase plasminogen activator (uPA) and metalloproteinases (MMP-2), and has shown antineoplastic effects both, in vitro and in vivo. This study aimed to evaluate the effects of a reengineered anthrax toxin on canine OMM. Five dogs bearing OMM without lung metastasis were included in the clinical study. Tumor tissue was analyzed by immunohistochemistry for expression of uPA, uPA receptor, MMP-2, MT1-MMP and TIMP-2. Animals received either three or six intratumoral injections of the reengineered anthrax toxin prior to surgical tumor excision. OMM samples from the five dogs were positive for all antibodies. After intratumoral treatment, all dogs showed stable disease according to the canine Response Evaluation Criteria in Solid Tumors (cRECIST), and tumors had decreased bleeding. Histopathology has shown necrosis of tumor cells and blood vessel walls after treatment. No significant systemic side effects were noted. In conclusion, the reengineered anthrax toxin exerted inhibitory effects when administered intratumorally, and systemic administration of this toxin is a promising therapy for canine OMM.

scholarly journals Non-alcoholic fatty liver disease in mice with hepatocyte-specific deletion of mitochondrial fission factor

Diabetologia ◽  
2021 ◽  
Author(s):  
Yukina Takeichi ◽  
Takashi Miyazawa ◽  
Shohei Sakamoto ◽  
Yuki Hanada ◽  
Lixiang Wang ◽  
...  
Keyword(s):  
Er Stress ◽  
Mitochondrial Dynamics ◽  
Mitochondrial Fission ◽  
Primary Hepatocytes ◽  
Alcoholic Fatty Liver ◽  
Expression Of Genes ◽  
Specific Deletion

Abstract Aims/hypothesis Mitochondria are highly dynamic organelles continuously undergoing fission and fusion, referred to as mitochondrial dynamics, to adapt to nutritional demands. Evidence suggests that impaired mitochondrial dynamics leads to metabolic abnormalities such as non-alcoholic steatohepatitis (NASH) phenotypes. However, how mitochondrial dynamics are involved in the development of NASH is poorly understood. This study aimed to elucidate the role of mitochondrial fission factor (MFF) in the development of NASH. Methods We created mice with hepatocyte-specific deletion of MFF (MffLiKO). MffLiKO mice fed normal chow diet (NCD) or high-fat diet (HFD) were evaluated for metabolic variables and their livers were examined by histological analysis. To elucidate the mechanism of development of NASH, we examined the expression of genes related to endoplasmic reticulum (ER) stress and lipid metabolism, and the secretion of triacylglycerol (TG) using the liver and primary hepatocytes isolated from MffLiKO and control mice. Results MffLiKO mice showed aberrant mitochondrial morphologies with no obvious NASH phenotypes during NCD, while they developed full-blown NASH phenotypes in response to HFD. Expression of genes related to ER stress was markedly upregulated in the liver from MffLiKO mice. In addition, expression of genes related to hepatic TG secretion was downregulated, with reduced hepatic TG secretion in MffLiKO mice in vivo and in primary cultures of MFF-deficient hepatocytes in vitro. Furthermore, thapsigargin-induced ER stress suppressed TG secretion in primary hepatocytes isolated from control mice. Conclusions/interpretation We demonstrated that ablation of MFF in liver provoked ER stress and reduced hepatic TG secretion in vivo and in vitro. Moreover, MffLiKO mice were more susceptible to HFD-induced NASH phenotype than control mice, partly because of ER stress-induced apoptosis of hepatocytes and suppression of TG secretion from hepatocytes. This study provides evidence for the role of mitochondrial fission in the development of NASH. Graphical abstract

scholarly journals Role of Vitamin D in the Prevention of Pancreatic Cancer

2010 ◽  
Vol 2010 ◽  
pp. 1-9 ◽  
Author(s):  
Pubudu Bulathsinghala ◽  
Kostas N. Syrigos ◽  
Muhammad W. Saif
Keyword(s):  
Pancreatic Cancer ◽  
Vitamin D ◽  
Dietary Intake ◽  
Sun Exposure ◽  
Current Treatment ◽  
Treatment Modalities ◽  
Hydroxyvitamin D ◽  
Vitamin D Levels ◽  
Advanced Stages

Pancreatic cancer is a malignancy of poor prognosis which is mostly diagnosed at advanced stages. Current treatment modalities are very limited creating great interest for novel preventive and therapeutic options. Vitamin D seems to have a protective effect against pancreatic cancer by participating in numerous proapoptotic, antiangiogenic, anti-inflammatory, prodifferentiating, and immunomodulating mechanisms. 25-hydroxyvitamin D [25(OH)D] serum concentrations are currently the best indicator of vitamin D status. There are three main sources of vitamin D: sun exposure, diet,and dietary supplements. Sun exposure has been associated with lower incidence of pancreatic cancer in ecological studies. Increased vitamin D levels seem to protect against pancreatic cancer, but caution is needed as excessive dietary intake may have opposite results. Future studies will verify the role of vitamin D in the prevention and therapy of pancreatic cancer and will lead to guidelines on adequate sun exposure and vitamin D dietary intake.

Abstract MP259: The Role Of Sertad4 In Pathological Cardiac Remodeling

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Matthew Stratton ◽  
Ashley Francois ◽  
Oscar Bermeo-Blanco ◽  
Alessandro Canella ◽  
Lynn Marcho ◽  
...  
Keyword(s):  
Cardiac Remodeling ◽  
Cardiac Fibrosis ◽  
Systolic Function ◽  
Myocardial Infarct ◽  
Proteasome Inhibition ◽  
Rna Seq ◽  
Expression Of Genes ◽  
M Phase ◽  
Tgf Β1

Over 6 million Americans suffer from heart failure (HF) while the 5-year mortality rate following first admission for HF is over 40%. Cardiac fibrosis is a clinical hallmark of HF, regardless of the initiating pathology and is thought to contribute to disease progression. Using an epigenomics discovery approach, we uncovered a nuclear protein, Sertad4, as a potential anti-fibrotic target. Our data indicate that Sertad4 is a positive regulator of fibroblast activation. Specifically, cultured cardiac fibroblast experiments demonstrate that Sertad4 targeting with shRNAs blocks fibroblast proliferation and causes cells to arrest in the G2/M phase of the cell cycle. Also, shRNA targeting of Sertad4 dramatically blocked activation of myofibroblast differentiation genes (αSMA/POSTN/COL1A1). Mechanistically, these effects appear to be mediated by Sertad4 regulation of SMAD2 protein stability in the presence of TGF-β1 stimulation as demonstrated by proteasome inhibition experiments. RNA-seq analysis indicate that Sertad4 also regulates the expression of genes involved in ubiquitination and proteasome degradation. Next, we sought to determine the effect of global Sertad4 knockout on post-myocardial infarct (MI) remodeling and cardiac function in mice. After 4 weeks of permanent LAD ligation, echocardiography was performed to measure systolic function. Relative to wild-type (WT) controls, the Sertad4 KO mice showed preserved systolic function as evident by improved ejection fraction (WT 14.4 +/- 3.6 vs. KO 33.9+/-5.9, p=0.035) and fractional shortening (WT 6.5 +/- 1.7 vs. KO 16.4 +/- 3.4, p=0.046). β-gal staining in the Sertad4/LacZ reporter mouse subjected to MI showed robust Sertad4/LacZ expression in the ischemic scar and boarder-zone with almost no expression in control hearts. This data supports the notion that Sertad4 has a key role in cardiac remodeling in response to ischemic injury.

scholarly journals Requirement for PKC Epsilon in Kras-Driven Lung Tumorigenesis

2020 ◽  
Author(s):  
Rachana Garg ◽  
Mariana Cooke ◽  
Shaofei Wang ◽  
Fernando Benavides ◽  
Martin C. Abba ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Lung Adenocarcinoma ◽  
Cancer Therapeutics ◽  
Rna Seq ◽  
Lung Tumorigenesis ◽  
Mechanistic Analysis ◽  
Oncogenic Driver ◽  
Histological Form

ABSTRACTNon-small cell lung cancer (NSCLC), the most frequent subtype of lung cancer, remains a highly lethal malignancy and one of the leading causes of cancer deaths worldwide. Mutant KRAS is the prevailing oncogenic driver of lung adenocarcinoma, the most common histological form of NSCLC. In this study, we examined the role of PKCε, an oncogenic kinase highly expressed in NSCLC and other cancers, in KRAS-driven tumorigenesis. Notably, database analysis revealed an association between PKCε expression and poor outcome in lung adenocarcinoma patients specifically having KRAS mutation. By generating a PKCε-deficient, conditionally activatable allele of oncogenic Kras (LSL-KrasG12D;PKCε−/− mice) we were able to demonstrate the requirement of PKCε for Kras-driven lung tumorigenesis in vivo, which is consistent with the impaired transformed growth observed in PKCε-deficient KRAS-dependent NSCLC cells. Moreover, PKCε-knockout mice were found to be less susceptible to lung tumorigenesis induced by benzo[a]pyrene, a carcinogen that induces mutations in Kras. Mechanistic analysis using RNA-Seq revealed little overlapping for PKCε and KRAS in the control of genes/biological pathways relevant in NSCLC, suggesting that a permissive role of PKCε in KRAS-driven lung tumorigenesis may involve non-redundant mechanisms. Our results thus highlight the relevance and potential of targeting PKCε for lung cancer therapeutics.

scholarly journals USP7 Inhibition Alleviates H2O2-Induced Injury in Chondrocytes via Inhibiting NOX4/NLRP3 Pathway

2021 ◽  
Vol 11 ◽  
Author(s):  
Gang Liu ◽  
Qingbai Liu ◽  
Bin Yan ◽  
Ziqiang Zhu ◽  
Yaozeng Xu
Keyword(s):  
Treatment Options ◽  
Current Treatment ◽  
Pathological Process ◽  
Joint Disease ◽  
Matrix Remodeling ◽  
Ros Production ◽  
Caspase 1 ◽  
Enhanced Production

Osteoarthritis (OA), the most common form of arthritis, is a very common joint disease that often affects middle-aged to elderly people. However, current treatment options for OA are predominantly palliative. Thus, understanding its pathological process and exploring its potential therapeutic approaches are of great importance. Rat chondrocytes were isolated and exposed to hydrogen peroxide (H2O2) to mimic OA. The effects of H2O2 on ubiquitin-specific protease 7 (USP7) expression, reactive oxygen species (ROS) levels, proliferation, inflammatory cytokine release, and pyroptosis were measured. USP7 was knocked down (KD) or overexpressed to investigate the role of USP7 in OA. Co-immunoprecipitation (Co-IP) was used to study the interaction between USP7 and NAD(P)H oxidases (NOX)4 as well as NOX4 ubiquitination. NOX4 inhibitor was applied to study the involvement of NOX4 in USP7-mediated OA development. USP7 inhibitor was given to OA animals to further investigate the role of USP7 in OA in vivo. Moreover, H2O2 treatment significantly increased USP7 expression, enhanced ROS levels, and inhibited proliferation in rat chondrocytes. The overexpression of USP7 enhanced pyroptosis, ROS production, interleukin (IL)-1β and IL-18 levels, and the expression level of NLRP3, GSDMD-N, active caspase-1, pro-caspase-1, matrix metalloproteinases (MMP) 1, and MMP13, which was abolished by ROS inhibition. The USP7 KD protected rat chondrocytes against H2O2-induced injury. Co-IP results showed that USP7 interacted with NOX4, and USP7 KD enhanced NOX4 ubiquitinylation. The inhibition of NOX4 blocked the pro-OA effect of USP7. Moreover, the USP7 inhibitor given to OA animals suppressed OA in vivo. USP7 inhibited NOX4 ubiquitination for degradation which leads to elevated ROS production. ROS subsequently activates NLPR3 inflammasome, leading to enhanced production of IL-1β and IL-18, GSDMD-N-dependent pyroptosis, and extracellular matrix remodeling. Thus, UPS7 contributes to the progression of OA via NOX4/ROS/NLPR3 axis.

scholarly journals The role of the NMD factor UPF3B in olfactory sensory neurons

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Kun Tan ◽  
Samantha H Jones ◽  
Blue B Lake ◽  
Jennifer N Dumdie ◽  
Eleen Y Shum ◽  
...  
Keyword(s):  
Human Cognition ◽  
Cell Populations ◽  
Rna Seq ◽  
Wild Type ◽  
Single Cell Rna Sequencing ◽  
Nonsense Mediated Rna Decay ◽  
Different Levels ◽  
Selection Of

The UPF3B-dependent branch of the nonsense-mediated RNA decay (NMD) pathway is critical for human cognition. Here, we examined the role of UPF3B in the olfactory system. Single-cell RNA-sequencing (scRNA-seq) analysis demonstrated considerable heterogeneity of olfactory sensory neuron (OSN) cell populations in wild-type (WT) mice, and revealed that UPF3B loss influences specific subsets of these cell populations. UPF3B also regulates the expression of a large cadre of antimicrobial genes in OSNs, and promotes the selection of specific olfactory receptor (Olfr) genes for expression in mature OSNs (mOSNs). RNA-seq and Ribotag analyses identified classes of mRNAs expressed and translated at different levels in WT and Upf3b-null mOSNs. Integrating multiple computational approaches, UPF3B-dependent NMD target transcripts that are candidates to mediate the functions of NMD in mOSNs were identified in vivo. Together, our data provides a valuable resource for the olfactory field and insights into the roles of NMD in vivo.

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