Therapeutic Effects of Ethyl Pyruvate on Tumor Growth and Metastasis in a Severe Combined Immunodeficiency Mouse Orthotopic Implantation Model

Ethyl pyruvate (EP) has been shown to have significant anti-inflammatory activities. Here, we explore the therapeutic effects of EP administration on tumor growth and metastasis in orthotopic implantation human gastric cancer models in severe combined immunodeficiency (SCID) mice. After SCID mice were treated with EP, the tumor growth and liver metastasis from gastric cancer were investigated and its possible molecular mechanisms were further studied. As a result, it was found that EP could inhibit tumor growth and liver metastasis of gastric cancer, and reduce tumor lymphangiogenesis indicated by lymphatic microvessel density (LVD) in gastric cancer and metastatic liver tumor. Also, EP decreased the expression of high mobility group box-B1 (HMGB1), receptor for advanced glycation endproducts (RAGE), vascular endothelial growth factor (VEGF) and membrane type-1 matrix metalloprotease (MT1-MMP) in gastric cancer and metastatic liver tumor, but it exerted no effect on expression of nuclear factor-kappa B (NF-κB). Taken together, we suggest that the new application of EP could be a therapeutic option in the treatment of gastric cancer and metastatic liver tumor.

A Chitinase from Aeromonas veronii CD3 with the potential to control myxozoan disease

Background

The class Myxosporea encompasses about 2,400 species, most of which are parasites of fish and cause serious damage in aquaculture. Due to the concerns about food safety issues and limited knowledge of Myxozoa life cycle and fish immune system, no chemicals, antibiotics or immune modulators are available to control myxozoa infection. Therefore, little can be done once Myxozoa establishment has occurred.

Methodology/Principal Findings

In this paper we isolated Aeromonas veronii CD3 with significant myxospore shell valve-degrading ability from pond sediment. A 3,057-bp full-length chitinase gene was consequently cloned, and the corresponding mature, recombinant chitinase (ChiCD3) produced by Escherichia coli had substantial chitinase activity. The deduced sequence of ChiCD3 contained one catalytic domain, two chitin-binding domains, and one putative signal peptide. ChiCD3 had an optimal activity at 50°C and pH 6.0, and retained more than 50% of its optimal activity under warm water aquaculture conditions (∼30°C and pH ∼7.0). After incubation with ChiCD3, 38.0±4.8% of the myxospores had damaged shell valves, whereas myxospores incubated with commercially available chitinases remained intact.

Conclusion/Significance

This study reveals a new strategy to control myxozoan disease. ChiCD3 that has capacity to damage the shell valve of myxospores can be supplemented into fish feed and used to control Myxozoa-induced diseases specifically.

PubChem's BioAssay Database

PubChem (http://pubchem.ncbi.nlm.nih.gov) is a public repository for biological activity data of small molecules and RNAi reagents. The mission of PubChem is to deliver free and easy access to all deposited data, and to provide intuitive data analysis tools. The PubChem BioAssay database currently contains 500,000 descriptions of assay protocols, covering 5000 protein targets, 30,000 gene targets and providing over 130 million bioactivity outcomes. PubChem's bioassay data are integrated into the NCBI Entrez information retrieval system, thus making PubChem data searchable and accessible by Entrez queries. Also, as a repository, PubChem constantly optimizes and develops its deposition system answering many demands of both high- and low-volume depositors. The PubChem information platform allows users to search, review and download bioassay description and data. The PubChem platform also enables researchers to collect, compare and analyze biological test results through web-based and programmatic tools. In this work, we provide an update for the PubChem BioAssay resource, including information content growth, data model extension and new developments of data submission, retrieval, analysis and download tools.

Neuronal Nogo-A regulates glutamate receptor subunit expression in hippocampal neurons

Nogo-A and its cognate receptor NogoR1 (NgR1) are both expressed in neurons. To explore the function of these proteins in neurons of the CNS, we carried out a series of studies using postnatal hippocampal neurons in culture. Interfering with the binding of Nogo-A to NgR1 either by adding truncated soluble fragment of NgR1 (NgSR) or by reducing NgR1 protein with a specific siRNA, resulted in a marked reduction in Nogo-A expression. Inhibition of Rho-ROCK or MEK-MAPK signaling resulted in a similar reduction in neuronal Nogo-A mRNA and protein. Reducing Nogo-A protein levels by siRNA resulted in an increase in the post-synaptic scaffolding protein PSD95, as well as increases in GluA1/GluA2 AMPA receptor and GluN1/GluN2A/GluN2B NMDA glutamate receptor subunits. siRNA treatment to reduce Nogo-A resulted in phosphorylation of mTOR; addition of rapamycin to block mTOR signaling prevented the up-regulation in glutamate receptor subunits. siRNA reduction of NgR1 resulted in increased expression of the same glutamate receptor subunits. Taken together the results suggest that transcription and translation of Nogo-A in hippocampal neurons is regulated by a signaling through NgR1, and that interactions between neuronal Nogo-A and NgR1 regulate glutamatergic transmission by altering NMDA and AMPA receptor levels through an rapamycin-sensitive mTOR-dependent translation mechanism.

Comparison of cryopreservation methods on T-cell responses to islet and control antigens from type 1 diabetic patients and controls

BACKGROUND

Type 1 diabetes (T1D) is a cell-mediated autoimmune disease characterized by destruction of the pancreatic islet cells. The use of cryopreserved cells is preferable to the use of freshly isolated cells to monitor clinical trials to decrease assay and laboratory variability.

METHODS

The T-Cell Workshop Committee of the Immunology of Diabetes Society compared two widely accepted T-cell freezing protocols (warm and cold) to freshly isolated peripheral blood mononuclear cells from patients with T1D and controls in terms of recovery, viability, cell subset composition, and performance in functional assays currently in use in T1D-related research. Nine laboratories participated in the study with four different functional assays included.

RESULTS

The cold freezing method yielded higher recovery and viability compared with the warm freezing method. Irrespective of freezing protocol, B cells and CD8+ T cells were enriched, monocyte fraction decreased, and islet antigen-reactive responses were lower in frozen versus fresh cells. However, these results need to take in to account that the overall response to islet autoantigens was low in some assays.

CONCLUSIONS

In the current study, none of the tested T-cell functional assays performed well using frozen samples. More research is required to identify a freezing method and a T-cell functional assay that will produce responses in patients with T1D comparable to responses using fresh peripheral blood mononuclear cells.

Identification of Differentially-Expressed Proteins between Early Submucosal Non-Invasive and Invasive Colorectal Cancer Using 2D-DIGE and Mass Spectrometry

Early detection and diagnosis of colorectal cancer (CRC) are closely related to a better therapeutic outcome, and the five-year survival rate of early CRC is over 90%. Though endoscopic minimally invasive treatment has become a quick and effective therapy for early CRC, endoscopic biopsies are usually not deep enough to obtain tissues from the submucosal layer and it is difficult to determine whether early CRC has infiltrated into the submucosa. Therefore, in the present study, we constructed tumor models of early submucosal non-invasive CRC (SNICRC) and submucosal invasive CRC (SICRC) in Fischer-344 rats induced by N-methyl-N-nitrosourea (MNU). The differentially-expressed proteins were analyzed and identified in SNICRC, SICRC and normal control (NC) tissues using highly sensitive two-dimensional differential gel electrophoresis (2D-DIGE) coupled with mass spectrometry (MS). Proteomic data revealed 132 protein spots between SNICRC and SICRC, 162 protein spots between SICRC and NC and 154 protein spots between SNICRC and NC which were found differentially expressed. These differential spots were picked, in-gel digested and peptide mass fingerprints were obtained by MALDI-TOF-MS/MS. Finally, five differentially-expressed proteins in SNICRC, SICRC and NC were identified, and increases in Transgelin, peptidylprolyl isomerase A (PPIA) and tropomyosin alpha isoform d were observed, while decreases in carbonic anhydrase 2 (CAII) and an unnamed protein were detected in SICRC compared with SNICRC and NC. Furthermore, Fluorescence-based quantitative polymerase chain reaction (FQ-PCR), Western blotting and immunohistochemistry assays also revealed significant upregulation of Transgelin expression and down-regulation of CAII expression in SICRC tissues. In conclusion, 2D-DIGE is confirmed to be an efficient strategy that enables us to identify differentially-expressed proteins between early SNICRC and SICRC. The potential biomarkers such as Transgelin and CAII may be used for the detection of early SICRC

Combined approach in bedside assessment of aspiration risk post stroke: PASS

BACKGROUND

Swallowing disorders are common and serious problems post stroke. Physical signs and ingestion test consist of main approaches of bedside screening of aspiration.

AIM

To assess the composability of these approaches.

DESIGN

A pilot study to develop a combined schema; secondly a validation study of this schema.

SETTING

Inpatient of Neurology Department and of Rehabilitation Department.

POPULATION

Forty-one patients post acute stroke included in the pilot study; 107 patients of subacute stroke for validation study.

METHODS

In pilot study, patients were assessed using Clinical Predicative Scale of Aspiration (CPSA) and 3-ounce Water swallow Test (3oz WT). Videofluoroscopic examination (VFSE) was performed as gold standard when the results of screening were discordant. In validation study, swallowing disorders were assessed systematically using CPSA, 3 oz WT and VFSE.

RESULTS

The combined screening schema, Practical Aspiration Screening Scheme (PASS), consisted of a 3oz WT to enhance results of the uncertain range of CPSA. Validation study showed that sensitivity and specificity of the 3oz WT were 87.3% and 42.3% respectively; those of CPSA were 50.1% and 50.0%, with a range of uncertainty in 42.6% of patients. The sensitivity of PASS was 89.1%, comparable to that of the 3oz WT, while the specificity of PASS was 80.8%, significantly higher than that of single tests. PASS also reduced systematic recourse to VFSE with a substantial agreement with it (kappa=0.7).

CONCLUSION

Physical signs and ingestion test are complementary in the screening of aspiration.

CLINICAL REHABILITATION IMPACT

Combined schema enhances the efficiency of bedside screening of aspiration.

Rho GTPase regulation of α-synuclein and VMAT2: implications for pathogenesis of Parkinson's disease

Accumulation of α-synuclein (Asyn) in neuronal perikarya and dystrophic neurites is characteristic of idiopathic and familial Parkinson's disease. In this study, we investigated the relationship between α-synuclein expression and neurite outgrowth-maturation using MN9D dopaminergic cells and demonstrated key features of Asyn regulation in hippocampal neurons. Neurite elongation elicited by inhibition of Rho GTPase activity with C3 transferase or by db-cAMP treatment was associated with marked reduction of α-synuclein mRNA and protein expression. Rho inhibition resulted in reduction of transcription factor SRF in the nuclear fraction and retention of MKL-1 - the SRF co-transactivator of SRE - in cytosol, indicating that these effects of Rho inhibition may be mediated though reduction of SRF-SRE transcription. Inhibition of Rho GTPase activity led to decreased nuclear localization of GATA2, a key regulator of α-synuclein promoter activity. Rho inhibition-induced neurite extension was associated with increased VMAT2 and SNARE proteins synaptophysin and synapsin I. These results indicate that in the MN9D dopaminergic cell line, α-synuclein transcription and levels of synaptic vesicle associated proteins are inversely correlated with neurite growth. We confirm that in mature hippocampal neurons inhibition of RhoA and knock down of SRF by siRNA also lead to decrease GATA2 and Asyn. The results suggest that RhoA signaling may be potential therapeutic target for the treatment of synucleinopathies.

[High expression and characterization of N-acyl-homoserine lactonase-xylanase recombinant protein]

OBJECTIVE

The fusion protein SL2B with both xylanase and N-acyl-homoserine lactonase activities was expressed in Pichia pastori. Characterization of the purified xylanase and N-acyl-homoserine lactonase fusion protein SL2B was investigated.

METHODS

The fusion gene sl2b was amplified from the N-acyl-homoserine lactonase gene aiiA-B546 and the xylanase gene xynAS27cd via overlap PCR technique. After the recombinant vector pPIC9/sl2b was transformed into P. pastoris, transformants with both xylanase and N-acyl-homoserine lactonase activity were screened. The purified SL2B was obtained with ammonium sulfate precipitation and molecular sieve. Both N-acyl-homoserine lactonase and xylanase activities of SL2B were characterized.

RESULTS

The purified SL2B showed that the xylanase had optimal pH and temperature at pH 6.5 and 60 degrees C, respectively. The enzyme was stable between pH 6.0 and 8.0, retained over 80% enzyme activity between 50 and 65 degrees C. It resisted various neutral proteases and chemical reagents. With oat spelt xylan as substrate, the Km value of SL2B was 2.9 mg/L. The N-acyl-homoserine lactonase had optimal pH and temperature at pH 8.0 and 30 degrees C, respectively. The enzyme was stable between pH 4.0 and 10.0, retained over 80% enzyme activity between 0 and 50 degrees C. It resisted various neutral proteases and chemical reagents. The fusion protein can hydrolyze many N-acyl homoserine lactones substrates. With N-(3-oxo-octanoyl)-L-homoserine lactone as substrate, the Km value of SL2B was 0.050 mmol/L.

CONCLUSION

High level expression is achieved by fusing N-acyl-homoserine lactonase to the xylanase.

Focal adhesion kinase regulates smooth muscle cell recruitment to the developing vasculature

OBJECTIVE

The investment of newly formed endothelial cell tubes with differentiated smooth muscle cells (SMC) is critical for appropriate vessel formation, but the underlying mechanisms remain unknown. We previously showed that depletion of focal adhesion kinase (FAK) in the nkx2.5 expression domain led to aberrant outflow tract (OFT) morphogenesis and strove herein to determine the cell types and mechanisms involved.

METHODS AND RESULTS

We crossed fak(loxp) targeted mice with available Cre drivers to deplete FAK in OFT SMC (FAK(wnt) and FAK(nk)) or coronary SMC (FAK(cSMC)). In each case, depletion of FAK led to defective vasculogenesis that was incompatible with postnatal life. Immunohistochemical analysis of the mutant vascular structures revealed that FAK was not required for progenitor cell proliferation, survival, or differentiation into SMC but was necessary for subsequent SMC recruitment to developing vasculature. Using a novel FAK-null SMC culture model, we found that depletion of FAK did not influence SMC growth or survival, but blocked directional SMC motility and invasion toward the potent endothelial-derived chemokine, platelet-derived growth factor PDGFBB. FAK depletion resulted in unstable lamellipodial protrusions due to defective spatial-temporal activation of the small GTPase, Rac-1, and lack of Rac1-dependent recruitment of cortactin (an actin stabilizing protein) to the leading edge. Moreover, FAK null SMC exhibited a significant reduction in stimulated extracellular matrix degradation.

CONCLUSIONS

FAK drives PDGFBB-stimulated SMC chemotaxis/invasion and is essential for SMC to appropriately populate the aorticopulmonary septum and the coronary vascular plexus.

Multi-conformation 3D QSAR study of benzenesulfonyl-pyrazol-ester compounds and their analogs as cathepsin B inhibitors

Cathepsin B has been found being responsible for many human diseases. Inhibitors of cathepsin B, a ubiquitous lysosomal cysteine protease, have been developed as a promising treatment for human diseases resulting from malfunction and over-expression of this enzyme. Through a high throughput screening assay, a set of compounds were found able to inhibit the enzymatic activity of cathepsin B. The binding structures of these active compounds were modeled through docking simulation. Three-dimensional (3D) quantitative structure-activity relationship (QSAR) models were constructed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) based on the docked structures of the compounds. Strong correlations were obtained for both CoMFA and CoMSIA models with cross-validated correlation coefficients (q²) of 0.605 and 0.605 and the regression correlation coefficients (r²) of 0.999 and 0.997, respectively. The robustness of these models was further validated using leave-one-out (LOO) method and training-test set method. The activities of eight (8) randomly selected compounds were predicted using models built from training set of compounds with prediction errors of less than 1 unit for most compounds in CoMFA and CoMSIA models. Structural features for compounds with improved activity are suggested based on the analysis of the CoMFA and CoMSIA contour maps and the property map of the protein ligand binding site. These results may help to provide better understanding of the structure-activity relationship of cathepsin B inhibitors and to facilitate lead optimization and novel inhibitor design. The multi-conformation method to build 3D QSAR is very effective approach to obtain satisfactory models with high correlation with experimental results and high prediction power for unknown compounds.