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The loss of inner ear hair cells leads to irreversible acoustic injury in mammals, and regeneration of inner ear hair cells to restore hearing loss is challenging.

The molecular repertoire of porcine alveolar macrophages (PAMs) is greatly affected by the microenvironment they are exposed to, and specifically by inflammatory cytokines, such as interferon gamma (IFN-γ) released by activated lymphocytes, and microbial products, such as lipopolysaccharide (LPS). In our previous study, we found that IFN-γ- and LPS-activated PAMs (M1) could inhibit porcine reproductive and respiratory syndrome virus (PRRSV) replication. In this study, comprehensive analysis of the expression profiles of the genes associated with the polarization of M0-type PAMs (resting) toward M1 phenotypes (activated by IFN-γ and LPS) led to the following main results: 1) 1551 and 1823 genes were upregulated or downregulated in M1-type PAMs, respectively, compared with M0-type PAMs; 2) Among these, genes encoding ASS1 and CRTAM were the most upregulated and downregulated, respectively; 3) Genes involved in cytokine-cytokine receptor interaction and the JAK/STAT signaling pathway were significantly upregulated, suggesting their critical role in cellular activation; and 4) Genes involved in antigen proteolysis and presentation (immunoproteasome subunits), and inhibition of virus replication (host restriction factors) were significantly upregulated, emphasizing the critical role of these cytokines in immunity. Thus, our results provide important information for future studies on the role of PAM polarization in modulation of infection.

Both the lung and the thymus are vital target organ for pathogens including viruses. The immunoproteasome (i-proteasome) enhances antigen presentation for MHC class I molecules to activate CD8+T lymphocyte. These facilitate antiviral adaptive immune response. Our previous study found that, expression of i-proteasome subunits in porcine lung was altered during normal and inflammatory conditions. To date, the expression of i-proteasome subunits in porcine thymus to viruses has not been investigated. In the present study, LMP2, LMP7, and MECL-1 were cloned, identified and their sequences encoded predicted proteins of 216, 275, and 278 amino acids, respectively. Expression of LMP2, LMP7, and MECL-1, in the cytoplasm and nucleus, was markedly altered in the porcine reproductive and respiratory syndrome virus (PRRSV)-infected lung and thymus. And dendritic cells and epithelial cells readily expressed the i-proteasome subunit LMP2 in the thymus of PRRSV-infected pigs compared to that in mock-infected pigs. Additionally, the in vitro stimulation of a PAM cell line with PolyI:C for 12 and 24 h resulted in increased LMP2, LMP7, and MECL-1 expression. These results suggest a central role for these complexes in the activation of an antiviral immune response in pigs. A better understanding of the role of the i-proteasome in different cell types, tissues, and hosts could improve vaccine design and facilitate the development of effective treatment strategies for viral infections.

The immunoproteasomes are specific proteasomes that clear oxidant-damaged proteins under inflammatory conditions in various diseases. Toxoplasma gondii (T. gondii) infects the central nervous system and causeencephalitis. However, the relationship between the immunoproteasomes and brain inflammation during T. gondii infection is not well characterized. In this study, we established an in vivo mouse model of T. gondii PLK strain infection via intraperitoneal injection and evaluated the expression of immunoproteasome subunits in the brains of infected mice. The results demonstrated that first, pathological changes in the brains of infected mice increase in severity over time. Second, following T. gondii infection, activated microglia and astrocytes undergo a series of functional alterations and morphological transformations, including proliferation and migration. Third, T. gondii infection induces expression of inflammatory cytokines, including IFN-γ, IL-1β, TNF-α, and IL-6. Fourth, the immunoproteasome subunits low-molecular-weight polypeptide 2 (LMP2), LMP7, and LMP10 mRNA and protein levels are significantly upregulated in T. gondii-infected mouse brains, as shown by RT-qPCR and western blot analysis, compared with that in vehicle-treated brains, and their expression is localized in the microglia, astrocytes, and neurons of T. gondii-infected brains, as determined via immunofluorescence staining. Furthermore, the western blot mean gray value for the immunoproteasome subunits and the positive microglia and astrocyte immunohistochemical signals in the brains of T. gondii-infected mice were positively correlated, indicating that the observed relationships were highly significant. Therefore, it was concluded that the induction of the immunoproteasomes is a pathogenic mechanism underlying T. gondii infection-induced inflammation.

The elimination of infected cells by cytotoxic T lymphocytes (CTLs) occurs through interactions between T cell receptors (TCRs) and pathogen-derived antigenic peptide-major histocompatibility complex (MHC) class I complexes. The immunoproteasome (i-proteasome), which is a large proteolytic machine derived from the constitutive proteasome, is highly efficient at processing antigens for presentation on MHC class I molecules to activate CD8+ T lymphocytes; this in turn facilitates antiviral adaptive immune responses. To date, i-proteasome expression in the porcine lung has not been investigated. In this study, we systematically analyzed the expression of the i-proteasome in vivo in the porcine lung and in vitro in alveolar macrophages (AMs) under normal and inflammatory conditions such as with IFN-γ stimulation or PRRSV infection. AMs were shown to readily express low levels of i-proteasome subunits, which were confined to the cytoplasm and nucleus under normal conditions. While i-proteasome expression could also be detected in other lung parenchymal cells including alveolar type I and II cells and bronchial epithelial cells during inflammatory conditions. Results showed that i-proteasome expression is markedly increased in IFN-γ-stimulated AMs and PRRSV-infected lung tissue. In addition, PRRSV infection promoted i-proteasome expression in AMs during the early stage of infection, and this was independent of IFN-γ; expression was attenuated during the later stage of infection in vitro. These results suggested that i-proteasome subunit expression can be induced in the porcine lung, which facilitates the development of antiviral adaptive immune responses against intracellular infections. These results could facilitate the development of therapeutics that target intracellular pathogens.

Toxoplasma gondii is an intracellular opportunistic, parasitic protozoan. Microglia have been classified into two main types: M1 (classically activated macrophages) and M2 (alternatively activated macrophages). BV2 cells were used in this study, together with lipopolysaccharide (LPS) and interferon (IFN)-γ or interleukin (IL)-4, which were used to induce resting microglia. Expression levels of M1/M2 markers were determined at both mRNA and protein levels, using PCR, western blot, and flow cytometry. Furthermore, cells were infected with T. gondii PLK strain, and the dynamic changes in M1/M2 marker expression levels were determined. An in vitro polarization model was successfully established. Expression of Nos2 and M1-associated markers was significantly upregulated at 12 h post-infection in BV2 cells. Further, the JAK/STAT1 and NF-κB signaling pathways were also activated following T. gondii infection. This demonstrated that T. gondii infection induces M1-type microglial polarization in vitro. The present study demonstrated that T. gondii infection affects microglial activation in vitro and elucidated the effects of activated microglia on T. gondii proliferation. This data may serve as a useful reference for more detailed elucidation of interactions between T. gondii and the innate immune system.

Two new coumarinolignoids, sapiumins D (1) and E (2), a new lignanoid, lariciresinol 9′-benzoate (3), together with six known coumarinolignoids (4–9) and eight known lignanoids (10–17), were isolated from the stems and leaves of Sapium discolor. The structures of the isolated compounds were elucidated by extensive spectroscopic methods, including NMR, MS, and single crystal X-ray diffraction experiments. Compounds 5, 10, 11, and 13 significantly inhibited nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells, with IC50 values in the range of 2.13–11.37 μM.

BackgroundInhibition of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) pathway improves the neurological outcome in the transient middle cerebral artery occlusion (tMCAO) animal model. In this study we analyzed the microRNAs profile targeting NOX2 and NOX4 genes and its response to NOX2/4 inhibitor VAS2870 to understand the mechanisms of this protective effect.MethodsThe intraluminal filament tMCAO model was established in hyperglycemic rats (n=106) with 5 hours ischemia followed by 19 hours reperfusion. NOX inhibitor VAS2870 was delivered intravenously before reperfusion. Infarct volume, hemorrhagic transformation, and mortality were determined at 24 hours after cerebral ischemia. MicroRNAs profile targeting NOX2 and NOX4 genes were predicted by microRNA databases and further evaluated by microRNA microarray and quantitative RT-PCR.ResultsTen microRNAs potentially targeting NOX2 and NOX4 genes (including microRNA-29a, microRNA-29c, microRNA-126a, microRNA-132, microRNA-136, microRNA-138, microRNA-139, microRNA-153, microRNA-337, and microRNA-376a) were significantly downregulated in the ischemic hemisphere in the tMCAO group compared with the sham-operated group, as shown by microRNA microarray and quantitative RT-PCR (all pConclusionsSeveral microRNAs potentially targeting NOX2 and NOX4 genes displayed altered levels in hyperglycemic rats with the tMCAO model, suggesting their regulatory roles and targeting potentials for acute ischemic stroke treatment. Targeting specific microRNAs may represent a novel intervention opportunity to improve outcome and reduce hemorrhagic transformation after mechanical reperfusion for acute ischemic stroke.

The tumor suppressor p53 and the transcriptional repressor Enhancer of Zeste Homolog 2 (EZH2) have both been implicated in the regulation of epithelial-mesenchymal transition (EMT) and tumor metastasis via their impacts on microRNA expression. Here, we report that mutant p53 (mutp53) promotes EMT in endometrial carcinoma (EC) by disrupting p68-Drosha complex assembly. Overexpression of mutp53 has the opposite effect of wild-type p53 (WTp53), repressing miR-26a expression by reducing pri-miR-26a-1 processing in p53-null EC cells. Re-expression of miR-26a in mutp53 EC cells decreases cell invasion and promotes mesenchymal-epithelial transition (MET). Rescuing miR-26a expression also inhibits EZH2, N-cadherin, Vimentin, and Snail expression and induces E-cadherin expression both in vitro and in vivo. Moreover, patients with higher serum miR-26a levels have a better survival rate. These results suggest that p53 gain-of-function mutations accelerate EC tumor progression and metastasis by interfering with Drosha and p68 binding and pri-miR-26a-1 processing, resulting in reduced miR-26a expression and EZH2 overexpression.

BackgroundSevere hemorrhagic transformation (HT) after mechanical thrombectomy predicts a poor clinical outcome in acute ischemic stroke. To better understand the mechanism of HT, we investigated the role of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) in HT after reperfusion during acute stroke and whether NOX2/4 inhibitor VAS2870 reduces reperfusion-induced HT after mechanical recanalization.MethodsA model of reperfusion-induced HT was established in rats (n=182) with hyperglycemic challenge and 5 h middle cerebral artery occlusion followed by 19 h reperfusion. NOX inhibitor VAS2870 was delivered intravenously 30 min before reperfusion. Infarct volume, brain water content, HT, neurological score, mortality rate, blood–brain barrier (BBB) damage, neuronal apoptosis, and reactive oxygen species were determined at 24 h after cerebral ischemia. The expressions of NOX1, NOX2, NOX4, and BBB-associated proteins were measured.ResultsNOX2 and NOX4 upregulation and severe HT were observed in hyperglycemic rats after cerebral ischemia/reperfusion. VAS2870 suppressed oxidative stress, neuronal apoptosis, and NOX2/4 upregulation in the ischemic hemisphere. VAS2870 reduced infarct volume (17.2±5.3% vs 37.4±9.2%, pConclusionsNOX2 and NOX4 may mediate HT in rats with large vessel stroke after mechanical reperfusion. Infusion of NOX inhibitor VAS2870 before mechanical thrombectomy represents a novel adjunctive therapeutic strategy to prevent reperfusion-induced HT and improve outcome of acute stroke treatment.

There is often a delay in offering quality and prompt treatment after a stingray sting. We present 3 cases of stings and discuss the Poisoning Severity Score (PSS) and a simple tool to assess the severity of such injuries. A 34-year-old man, who worked as an aquarium keeper, presented a wound on the left fifth digit caused by a stingray. Acute myocardial injury and rhabdomyolysis were detected. After 6weeks, the wound had almost healed. A 27-year-old man who experienced a stingray injury on the left second digit recovered without sequelae after 5weeks. A 45-year-old man with a history of diabetes, who was accidentally stung in the right palm by a stingray, experienced rhabdomyolysis and returned to work after 2months. We performed debridement, administered the tetanus toxoid and antibiotics, and immersed the wounded hand in warm water (about 43°C) for all three cases. Meanwhile, patients with rhabdomyolysis were administered intravenous hydration. Upon presentation at the emergency department, we recorded the severity of the injury by using PSS. We found that relatively high PSSs were associated with lower platelet counts that happen due to various adverse events. We suggest that dynamic changes in platelet counts may be associated with the severity of the injury. Furthermore, lower platelet counts in the normal or abnormal range may indicate poor prognoses.

The baculovirus-induced actin polymerization is mainly associated with the virus nucleocapsid protein P78/83, which is homologous with WASP proteins that can activate Arp2/3 complex and induce the actin polymerization. In order to explore the role of Arp2/3 complex in the baculovirus replication, the P40 subunit of Arp2/3 complex from Sf9 (Spodoptera frugiperda 9) cell line was cloned and characterized. Immunofluorescent microscopy assay indicated that P40 was recruited to the inner-side of nuclear membrane during virus infection, which was in accordance with nuclear F-actin distribution in virus-infected cells as documented in our previous research, suggesting P40 could be used to track Arp2/3 complex subcellular distribution changes during virus infection. In addition, co-immunoprecipitation assay demonstrated that P40 interacted with P78/83 only in virus-infected cells, suggesting that actin polymerization induced by P78/83-Arp2/3 complex during baculovirus infection was regulated by some unidentified virus factors.

Glycine serves a dual role in neurotransmission. It is the primary inhibitory neurotransmitter in the spinal cord and brain stem and is also an obliga- tory coagonist at the excitatory glutamate, N-methyl-D-aspartate receptor (NMDAR). Therefore, the postsynaptic action of glycine should be strongly regulated to maintain a balance between its inhibitory and excitatory inputs. The glycine concentration at the synapse is tightly regulated by two types of glycine transporters, GlyT1 and GlyT2, located on nerve terminals or astrocytes. Genetic studies demonstrated that homozygous (GlyT12/2) newborn mice display severe sensorimotor deficits character- ized by lethargy, hypotonia, and hyporesponsivity to tactile stimuli and ultimately die in their first postnatal day. These symptoms are similar to those associated with the human disease glycine encephalopathy in which there is a high level of glycine in cerebrospinal fluid of affected individuals. The purpose of this investigation is to determine the impact of chronically high concentrations of endogenous glycine on glutamatergic neurotransmission during postnatal development using an in vivo mouse model (GlyT11/2). The results of our study indicate the following; that compared with wild-type mice, CA1 pyramidal neurons from mutants display signifi- cant disruptions in hippocampal glutamatergic neurotransmission, as suggested by a faster kinetic of NMDAR excitatory postsynaptic currents, a lower reduction of the amplitude of NMDAR excitatory postsynaptic currents by ifenprodil, no difference in protein expression for NR2A and NR2B but a higher protein expression for PSD-95, an increase in their number of synapses and finally, enhanced neuronal excitability. Synapse 65:1181-1195, 2011. V C 2011 Wiley-Liss, Inc.

To investigate the protective effect of glutamine in rats with pseudomonas pneumonia receiving total parenteral nutritional (TPN) therapy.Forty Sprague-Dawley rats were randomly divided into 4 groups (Group A, B, C and D). Rats in Group A received, by intra-tracheal route, infusion of 0.3 ml normal saline. Rats in Group B received, also by intra-tracheal route, infusion of 0.3 ml pseudomonas aeruginosa soliquoid so that the bacteria entered the lungs directly. A standard TPN solution not containing glutamine was administered intravenously to rats in Group C (160 ml/kg) for 5 days, and a TPN solution containing glutamine was administered intravenously to rats in Group D (160 ml/kg) for 5 days. On day 6, 0.3 ml pseudomonas aeruginosa soliquoid was administered by intra-tracheal route to rats in Group C and D. The weight of rats, their activity and mortality were recorded. 48 h after intratracheal administration, blood and bronchoalveolar lavage fluid (BALF) samples were collected for measurement of white blood cell count, TNFalpha, IL-1, IL-10 and total protein of BALF. Segments of the lung, the liver and the ileum tissues were collected for HE pathological slice.(1) Initially there was no difference in weight between the four groups, but on day 8 the weights of rats in Group B, C, and D were significantly decreased compared with that in Group A (P0.05). The mortality of rats in Group C was significantly higher than that in Group B and D (P0.05). (2) There were significant differences between Group C and D in white blood cell count, blood TNFalpha and IL-10 level, BALF, and total protein of BALF (P0.05). (3) Pathological changes of the lung, the liver and ileum in Group C were more severe than that in Group B and D. Group A was basically normal.Glutamine is able to protect gastrointestinal tract function in rats receiving TPN, to improve pulmonary anti-infection ability, and to alleviate injuries of important organs caused by severe infection.

Most cortical interneurons are generated in the subpallial ganglionic eminences and migrate tangentially to their final destinations in the neocortex. Within the cortex, interneurons follow mainly stereotype routes in the subventricular zone/intermediate zone (SVZ/IZ) and in the marginal zone. It has been suggested that interactions between invading interneurons and locally generated projection neurons are implicated in the temporal and spatial regulation of the invasion process. However, so far experimental evidence for such interactions is lacking.We show here that the chemokine stromal-derived factor 1 (SDF-1; CXCL12) is expressed in the main invasion route for cortical interneurons in the SVZ/IZ. Most SDF-1-positive cells are proliferating and express the homeodomain transcription factors Cux1 and Cux2. Using MASH-1 mutant mice in concert with the interneuron marker DLX, we exclude that interneurons themselves produce the chemokine in an autocrine manner. We conclude that the SDF-1-expressing cell population represents the precursors of projection neurons during their transition and amplification in the SVZ/IZ. Using mice lacking the SDF-1 receptor CXCR4 or Pax6, we demonstrate that SDF-1 expression in the cortical SVZ/IZ is essential for recognition of this pathway by interneurons. These results represent the first evidence for a molecular interaction between precursors of projection neurons and invading interneurons during corticogenesis.

To produce prokaryotic recombinant protein glyceraldehyde-3 phosphate dehydrogenase of Clonorchis sinensis (CsGAPDH), analyze its enzyme activity and immunological function. Methods The recombinant CsGAPDH was purified according to the protocol of GST-Bind kit and was digested with thrombin proteinase and eluted with wash buffer. The BALB/c mice were inoculated with the purified protein. The antisera collected from the mice were used to detect the titres of IgG antibodies by ELISA, and Western blotting was used to identify the specificity of the antisera with the purified CsGAPDH. S-P immunohistochemistry method was used to confirm the expression and distribution of CsGAPDH in adult Clonorchis sinensis with the polyclonal antibodies from immunized BALB/c mice. The CsGAPDH catalytic activity was evaluated employing the conventional substrate glyceraldehyde-3-phosphate (3-GAP).SDS-PAGE showed a single purified protein band. Gel scanning analysis revealed that the protein purity of CsGAPDH was 90%. ELISA analysis showed an increased IgG value. S-P immunohistochemistry analysis demonstrated that the recombinant plasmid pGEX-4T-1 GAPDH expressed and distributed in muscle cell membrane of immune mice. Western blotting result suggested that CsGAPDH protein contained essential epitopes with high antigenic activities. This protein CsGAPDH could catalyzed 3-GAP with enzymatic active unit of 2872 U min(-1) ml(-1).The recombinant protein CsGAPDH shows a proper enzymatic activity and immunogenicity.

To construct prokaryotic recombinant plasmids of transcriptional co-activator (TC) gene of Clonorchis sinensis, express and purify the recombinant protein and analyze its biological function.A pair of primers was designed according to the known sequence of TC gene. The TC gene fragment was amplified by PCR. After purification and digestion with BamH I and Sal I, the TC gene was connected to the prokaryotic expression vectors, pGEX-4T-1 and pET30a(+). By cloning target gene into these vectors, pGEX-4T-1 and pET30a(+), prokaryotic recombinant plasmids of TC gene were constructed and transferred into E. coli BL21. The positive expressed recombinants were detected by SDS-PAGE and Western blotting. Immobilized metal (Ni2+) chelation affinity chromatography was used to purify His-TC produced by the expression of the recombinant protein pET30a(+)-TC.The recombinant plasmids, pGEX-4T-1-TC and pET30a(+)-TC, were constructed successfully. SDS-PAGE testified that the molecular weight of the recombinant protein was correct. Western blot analysis of GST-TC recombinant protein testified that the recombinant protein could be recognized by immunized rabbit serum, which means the protein is GST-immune active and the clone can express recombinant Clonorchis sinensis antigen. After affinity chromatography of the pET-TC protein, there was only one protein band with expected size on the SDS-PAGE gel.The TC gene was screened from cDNA library of adult Clonorchis sinensis, cloned, expressed and purified. The purified protein of TC gene will be of importance for further research on the biological function of the gene.

To study the etiological role of human papillomavirus type 16 (HPV16) infection in the development of esophageal cancers.A recombinant retrovirus containing the E6E7 ORFs of HPV16 was packaged and human fetal esophageal fibroblasts were infected. The tumorigenecity of the fibroblasts was tested in SCID mice in synergy with 12-O-tetradecanoylphorbol-13-acetate (TPA).Human esophageal fibroblasts infected with the recombinant retrovirus induced sarcomas in SCID mice, the existence and expression of E6E7 ORFs was confirmed in the sarcomas. Fibroblasts cultured from the sarcoma were demonstrated heteroploid by cytoflowmetry. However, tumors were not observed in human fetal esophagus infected with such virus.These results revealed that the established recombinant retroviral system can successfully mediate the transference of HPV16 E6E7 genes, and such system is applicable to researches on tumorigenesis of HPV.

To study a new quick method for detecting serum IgG against Trichinella spiralis (T.s).Membrane antigen of muscle larva of T.s was isolated and combined with the nitrocellulose membrane. Goat anti-human IgG was conjugated with the golden pellets of colloidal state which was used as marked antibody for the experiment of dot-immunogold filtration assay to examine specific IgG.T.s IgG and its corresponding antigen reacted on the membrane by filtration, and the result could be observed with naked eyes within 10 min. In the examination of 76 clinical serum samples, the positive rate was 94.7%. It was not significantly higher than that of ELISA (chi 2 = 2.83, P0.05).The dot-immunogold filtration assay is rapid and simple for performing and reading in the detection of IgG against T.s with high sensitivity and specificity.