Biochemical and biophysical research communications
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Biochem. Biophys. Res. Commun. · Jun 2010
TLR4-mediated activation of mouse macrophages by Korean mistletoe lectin-C (KML-C).
Korean mistletoe lectin (KML-C) is an adjuvant that activates systemic and mucosal immune cells to release cytokines including TNF-alpha, which induces immunity against viruses and cancer cells. Although the immunomodulatory activity of KML-C has been well established, the underlying mechanism of action of KML-C has yet to be explored. When mouse peritoneal macrophages were treated with KML-C, both transcription and translation of TLR4 were upregulated. ⋯ Moreover, TLR4-deficient mouse macrophages treated with KML-C also secreted greatly reduced level of TNF-alpha secretion. Finally, TLR4 molecules were co-precipitated with KML-C, to which agarose beads were conjugated, indicating that those molecules are associated. These data indicate that KML-C activates mouse macrophages to secrete TNF-alpha by interacting with the TLR4 molecule and activating its signaling pathways.
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Biochem. Biophys. Res. Commun. · May 2010
Spinal high-mobility group box 1 contributes to mechanical allodynia in a rat model of bone cancer pain.
Mechanisms underlying bone cancer-induced pain are largely unknown. Previous studies indicate that neuroinflammation in the spinal dorsal horn is especially involved. Being first reported as a nonhistone chromosomal protein, high-mobility group box 1 (HMGB1) is now implicated as a mediator of inflammation. ⋯ Tumor cells inoculation significantly increased HMGB1 expression in the spinal dorsal horn, while intrathecal injecting a neutralizing antibody against HMGB1 showed an effective and reliable anti-allodynia effect with a dose-dependent manner. IL-1beta was significantly increased in cancer pain rats while intrathecally administration of anti-HMGB1 could decrease IL-1beta. Together with previous reports, we predict that bone cancer induces HMGB1 production, enhancing spinal IL-1beta expression and thus modulating spinal excitatory synaptic transmission and pain response.
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Biochem. Biophys. Res. Commun. · Mar 2010
Clinical TrialSerum miR-146a and miR-223 as potential new biomarkers for sepsis.
Current biomarkers cannot completely distinguish sepsis from systemic inflammatory response syndrome (SIRS) caused by other non-infectious diseases. Circulating microRNAs (miRNAs) are promising biomarkers for several diseases, but their correlation with sepsis is not totally clarified. ⋯ Serum miR-146a and miR-223 might serve as new biomarkers for sepsis with high specificity and sensitivity. (ClinicalTrials.gov number, NCT00862290.).
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Biochem. Biophys. Res. Commun. · Feb 2010
Down-regulation of Notch1 by gamma-secretase inhibition contributes to cell growth inhibition and apoptosis in ovarian cancer cells A2780.
The release of Notch intracellular domain (NICD) is mediated by gamma-secretase. gamma-Secretase inhibitors have been shown to be potent inhibitors of NICD. We hypothesized that Notch1 is acting as an oncogene in ovarian cancer and that inhibition of Notch1 would lead to inhibition of cell growth and apoptotic cell death in ovarian cancer cells. In this study, expressions of Notch1 and hes1 in four human ovarian cancer (A2780, SKOV3, HO-8910, and HO-8910PM), and one ovarian surface (IOSE 144) cell lines were detected by Western blot and quantitative real-time RT-PCR. ⋯ In addition, hes1 was found to be down-regulated in dose- and time-dependent manner by DAPT in A2780. These results demonstrate that treatment with DAPT leads to growth inhibition and apoptosis of A2780 cells in dose- and time-dependent manner. These findings also support the conclusion that blocking of the Notch1 activity by gamma-secretase inhibitors represents a potentially attractive strategy of targeted therapy for ovarian cancer.
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Biochem. Biophys. Res. Commun. · Jan 2010
A murine model of sepsis following smoke inhalation injury.
Acute lung injury (ALI) by smoke inhalation with subsequent pneumonia and sepsis represents a major cause of morbidity and mortality in burn patients. The aim of the present study was to develop a murine model of ALI and sepsis to enhance the knowledge of mechanistic aspects and pathophysiological changes in patients with these injuries. In deeply anesthetized female C57BL/6 mice, injury was induced by four sets of cotton smoke using an inhalation chamber. ⋯ However, smoke alone significantly increased neutrophil accumulation and formation of reactive nitrogen species in lung tissue. In conclusion, bacterial pneumonia is predominantly responsible for mortality and morbidity in this novel murine model of smoke inhalation and pulmonary sepsis. Reactive oxygen and nitrogen species mediate the severity of lung injury.