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Sepsis is life-threatening organ dysfunction due to dysregulated systemic inflammatory and immune response to infection, often leading to cognitive impairments. Growing evidence shows that artemisinin, an antimalarial drug, possesses potent anti-inflammatory and immunoregulatory activities. In this study we investigated whether artemisinin exerted protective effect against neurocognitive deficits associated with sepsis and explored the underlying mechanisms. Mice were injected with LPS (750 μg · kg -1  · d -1 , ip, for 7 days) to establish an animal model of sepsis. Artemisinin (30 mg · kg -1  · d -1 , ip) was administered starting 4 days prior LPS injection and lasting to the end of LPS injection. We showed that artemisinin administration significantly improved LPS-induced cognitive impairments assessed in Morris water maze and Y maze tests, attenuated neuronal damage and microglial activation in the hippocampus. In BV2 microglial cells treated with LPS (100 ng/mL), pre-application of artemisinin (40 μΜ) significantly reduced the production of proinflammatory cytokines (i.e., TNF-α, IL-6) and suppressed microglial migration. Furthermore, we revealed that artemisinin significantly suppressed the nuclear translocation of NF-κB and the expression of proinflammatory cytokines by activating the AMPKα1 pathway; knockdown of AMPKα1 markedly abolished the anti-inflammatory effects of artemisinin in BV2 microglial cells. In conclusion, atemisinin is a potential therapeutic agent for sepsis-associated neuroinflammation and cognitive impairment, and its effect is probably mediated by activation of the AMPKα1 signaling pathway in microglia.

Various nanoparticles, such as silver nanoparticles (AgNPs) and titanium nanoparticles (TiO 2 NPs) are increasingly used in industrial processes. Because they are released into the environment, research into their influence on the biosphere is necessary. Among its other effects, dietary TiO 2 NPs promotes silk protein synthesis in silkworms, which prompted our hypothesis that TiO 2 NPs influence protein kinase B (Akt)/Target of rapamycin (Tor) signaling pathway (Akt/Tor) signaling in their silk glands. The Akt/Tor signaling pathway is a principle connector integrating cellular reactions to growth factors, metabolites, nutrients, protein synthesis, and stress. We tested our hypothesis by determining the influence of dietary TiO 2 NPs (for 72 h) and, separately, of two Akt/Tor pathway inhibitors (LY294002 and rapamycin) on expression of Akt/Tor signaling pathway genes and proteins in the silk glands. TiO 2 NPs treatments led to increased accumulation of mRNAs for Akt, Tor1 and Tor2 by 1.6-, 12.1-, and 4.8-fold. Dietary inhibitors led to 2.6- to 4-fold increases in mRNAs encoding Akt and substantial decreases in mRNAs encoding Tor1 and Tor2. Western blot analysis showed that dietary TiO 2 NPs increased the phosphorylation of Akt and its downstream proteins. LY294002 treatments led to inhibition of Akt phosphorylation and its downstream proteins and rapamycin treatments similarly inhibited the phosphorylation of Tor-linked downstream proteins. These findings support our hypothesis that TiO 2 NPs influence Akt/Tor signaling in silk glands. The significance of this work is identification of specific sites of TiO 2 NPs actions., (© 2018 Wiley Periodicals, Inc.)

Objective: To study the correlation between the excessive activation of Hedgehog signal and the drug resistance of multiple myeloma., Methods: The resistant cell line RPMI 8226/R of multiple myeloma was established by an ascending concentration gradient method. The experiment consisted of 4 groups: RPMI8226/R, RPMI8226/S, GANT61+RPMI8226/R and GANT61+RPMI8226/S. The CCK-8 (cell counting kit-8) assay was used to detect the cell proliferation inhibition rate in 4 groups; the RT-PCR was used to detect the expression of Gli1, Gli2, Shh, Ihh, Smo and Sufu in the RPMI8226/S and RPMI8226/R cells. The Western blot was used to detect the expression of the resistant protein Cyclin D1, P21 and BCL-2 and MDR-related signaling pathways protein p-Akt, p-MAPK and STAT3 in the RPMI8226/S and RPMI8226/R cells. After adding different concentration of GANT61, the Western blot was used to detect the expression of Gli2 in RPMI8226/R and RPMI8226/S cells., Results: The expression of Shh, Ihh, Smo Gli2 was enhanced significantly in the RPMI8226/R cells, but the expression of Sufu inhibitor was reduced, the expression level of related protein in Hedgehog signaling pathway was significanly higher in RPMI8226/R than that in RPMI8226/S. After theatment of GANT61 in vitro, the expression level of Gli2 in multiple myelom cells obviously decreased, the decreasing effect of GANT61 on Gli2 expression in RPMI8226/R cells was more significant than that in RPMI8226/S cells. The sensitivity of RPMI8226/R cells to DOX after treatment with GANT61 (IC 50 ) was risen from 7.11±0.061 µmol/L to 0.99±0.053 µmol/L, the corresponding cell resistance index decreased from 5.51 to 1.69., Conclusion: the activation of Hedgehog signaling pathway is closely related with the resistance of multiple myeloma cells, and GANT61 can block the Hedgehog signaling pathway, thus Hedgehog signaling may be used as a new target for multiple myeloma treatment.

Polydnaviruses (PDVs) play a critical role in altering host gene expression to induce immunosuppression. However, it remains largely unclear how PDV genes affect host genes. Here, the complete genome sequence of Microplitis bicoloratus bracovirus (MbBV), which is known to be an apoptosis inducer, was determined. The MbBV genome consisted of 17 putative double-stranded DNA circles and 179 fragments with a total size of 336,336 bp and contained 116 open reading frames (ORFs). Based on conserved domains, nine gene families were identified, of which the IκB-like viral ankyrin (vank) family included 28 members and was one of the largest families. Among the 116 ORFs, 13 MbBV genes were expressed in hemocytes undergoing MbBV-induced apoptosis and further analyzed. Three vank genes (vank86, vank92, vank101) were expressed in hemocytes collected from Spodoptera litura larvae parasitized by M. bicoloratus, in which host NF-κB/IκBs, including relish, dorsal, and cactus, were also persistently expressed. When Spli221 cells were infected with MbBV viral particles, mRNA levels of host and viral NF-κB/IκB genes were persistent and also varied in Spli221 cells undergoing virus-induced pre-apoptosis cell from 1 to 5 hours postinfection. Both were then expressed in a time-dependent expression in virus-induced apoptotic cells. These data show that viral IκB-like transcription does not inhibit host NF-κB/IκB expression, suggesting that transcription of these genes might be regulated by different mechanisms.

Aim: To investigate the role of the Notch1 signaling pathway in growth arrest of an esophageal carcinoma cell line (EC109) in vitro and the mechanism involved., Methods: An intracellular domain of Notch1 (ICN) was transfected into cultured EC109 cells by lipofectamine transfection. Subsequently, the proliferation of the transfected cells was measured by an MTT assay. Cell cycle distribution was analyzed by flow cytometry. Human papillomavirus type 18 (HPV18) E6/E7 mRNA expression was detected by RT-PCR, and p53 protein expression was detected by Western blot., Results: Activation of Notch1 signaling resulted in inhibition of EC109 cell proliferation with the induction of G(2)/M arrest, downmodulation of HPV18 E6/E7 gene expression, and upregulation of p53 expression., Conclusion: Repression of HPV18 E6/E7 expression by Notch1 signaling results in the activation of p53-mediated pathways with concomitant growth suppression of HPV18-positive EC109 cells.

Purpose: Previous studies have identified sequences encoding vascular endothelial growth factor (VEGF)-A and one of the VEGF receptors (VEGFR2, Flk-1, KDR) in lens fiber cells. The current study was undertaken to determine the distribution of VEGF-A protein in the lens, whether signaling through VEGF receptors occurs in lens cells, the pattern of VEGF-A expression during lens development, and the effect of hypoxia on VEGF-A expression., Methods: VEGF-A and VEGFR2 were localized using immunocytochemistry. VEGF-A and VEGFR2 protein were identified and quantified by Western blot analysis. Activated (tyrosine phosphorylated) VEGFR2 was detected by immunoprecipitation with an anti-phosphotyrosine antibody followed by Western blot analysis with antibody to VEGFR2. Levels of VEGF-A mRNA were measured by quantitative PCR. Suturing the lids of adult mouse or rabbit eyes for 3 days was used to induce lens hypoxia., Results: VEGFR2 sequences were present in adult human lens epithelial cells, and VEGF-A transcripts were detected in chicken embryo, adult human, and mouse lens epithelial cells. VEGF-A protein localized to the ends of mouse embryo lens fiber cells at developmental stages when the fetal vasculature was forming. At later stages, VEGF-A was distributed uniformly throughout the cytoplasm of cortical fiber cells. VEGFR2 was present in mouse lens epithelial and fiber cells and was tyrosine phosphorylated at all stages examined. VEGF-A protein was barely detectable in lens epithelial cells during the first postnatal week, but increased as the capillaries of the anterior pupillary membrane regressed. VEGF-A levels were highest in adult lenses. Suturing the eyelid caused an increase in VEGF-A mRNA and protein in lens epithelial and fiber cells., Conclusions: VEGF-A secreted by lens cells may stimulate the formation of the fetal vasculature, but regression of these vessels is not likely to be caused by a reduction in VEGF-A production by the lens. An active VEGF-A signaling system of unknown function appears to be active in the lens. It is likely that VEGF-A expression is regulated by tissue hypoxia at all stages of lens development.