Effects of the interleukin-21 expression in patients with immune thrombocytopenia and its regulation by high-dose dexamethasone / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the correlation of immunologic thrombocytopenia(ITP) pathogenesis with the abnormal expression of IL-21, and to explore the association of high-dose dexamethasone (HD-DEX) treatment with the IL-21 expression.</p><p><b>METHODS</b>26 newly diagnosed ITP patients and 24 healthy controls were enrolled in this study. The mononuclear cells and serum were obtain from density gradient centrifugation in the newly diagnosed ITP patients before HD-DXM treatment, and the samples of healthy controls were also used for assays. The protein and mRNA expression of IL-21 on peripheral blood mononuclear cells(MNC) were determined by flow cytometry and real-time reverse-transcription polymerase chain reaction. Plasma levels of IL-21, IFN-γ and IL-4 were determined by enzyme-linked immunoabsorbent assay (ELISA).</p><p><b>RESULTS</b>IL-21 expression on mononuclear cells was significantly higher in ITP patients (13.07%) than that in normal controls (8.2%), the ratio of IL-21/GAPDH mRNA expression on MNC was significantly higher in ITP patients (9.524±0.97) than that in normal controls (3.701±0.60, P<0.01). After HD-DXM therapy, the ratio of IL-21/GAPDH mRNA decreased significantly (5.87±1.21) as compared with the level before treatment. Significantly high levels of serum IL-21, IFN-γ and lower IL-4 were found in ITP patients, as compared with healthy controls. Serum IL-21 and IFN-γ levels in ITP patients decreased significantly after HD-DXM administration (P<0.01), while post-treatment levels of IL-4 were increased significantly, compared with the levels before treatment (P<0.01).</p><p><b>CONCLUSION</b>Therapeutic effect of DXM on ITP associates with down-regalation of IL-21 expression. The increased expression of IL-21 involves in the pathogenesis of ITP.</p>

Perfluorocarbon attenuates lipopolysaccharide-mediated inflammatory responses of alveolar epithelial cells in vitro / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Toll-like receptor-4 (TLR-4) is integrally involved in lipopolysaccharide (LPS) signaling and has a requisite role in the activation of nuclear factor-κB (NF-κB). The exact mechanisms that lend perfluorocarbon (PFC) liquids a cytoprotective effect have yet to be elucidated. Therefore we examined in an in vitro model the cytoprotective effect of PFC on LPS-stimulated alveolar epithelial cellls (AECs).</p><p><b>METHODS</b>AECs (A549 cells, human lung adenocarcinoma cell line) were divided into four groups: control, PFC, LPS and LPS + PFC (coculture group) groups. Intercellular adhesion molecule-1 (ICAM-1) was detected by ELISA, tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8) were detected by radioimmunological methods. The expression of TLR-4 mRNA and protein was detected by real time PCR and Western blotting, respectively. The activation of NF-κB was detected by Western blotting (proteins of I-κBa and NF-κB p65).</p><p><b>RESULTS</b>ICAM-1, TNF-α and IL-8 were significantly increased in LPS-stimulated AECs groups. The expression of TLR-4 mRNA and protein in LPS-stimulated groups was markedly increased. Meanwhile, NF-κB was activated as indicated by the significant degradation of IκB-α and the significant release of NF-κB P65 and its subsequent translocation into the nucleus. There were no significant effects of PFC alone on any of the factors studied while the coculture group showed significant downregulation of the secretion of ICAM-1, TNF-α and IL-8, the expression of TLR-4 mRNA and the activity of NF-κB.</p><p><b>CONCLUSIONS</b>Taken together, our results demonstrate that LPS can induce AEC-related inflammatory injury via the activation of TLR-4 and subsequent activation of NF-κB. PFC is able to protect AECs from LPS-induced inflammatory injury by blocking the initiation of the LPS signaling pathway, which is indicated by the significant decrease of TLR-4 expression and NF-κB activation.</p>

Gefitinib attenuates murine pulmonary fibrosis induced by bleomycin / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Gefitinib, an inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, is an effective treatment for epithelial tumors, including non-small cell lung cancer (NSCLC), and is generally well tolerated. However, some clinical trials revealed that gefitinib exposure caused lung fibrosis, a severe adverse reaction. This study investigated the effect of gefitinib on lung fibrosis in mice.</p><p><b>METHODS</b>We generated a mouse model of lung fibrosis induced by bleomycin to investigate the fibrotic effect of gefitinib. C57BL/6 mice were injected intratracheally with bleomycin or saline, with intragastric administration of gefitinib or saline. Lung tissues were harvested on day 14 or 21 for histology and genetic analysis.</p><p><b>RESULTS</b>The histological results showed that bleomycin successfully induced lung fibrosis in mice, and gefitinib prevented lung fibrosis and suppressed the proliferation of S100A4-positive fibroblast cells. In addition, Western blotting analysis revealed that gefitinib decreased the expression of phosphorylated EGFR (p-EGFR). Furthermore, quantitative real-time PCR (qRT-PCR) demonstrated that gefitinib inhibited the accumulation of collagens I and III.</p><p><b>CONCLUSIONS</b>These results reveal that gefitinib reduces pulmonary fibrosis induced by bleomycin in mice and suggest that administration of small molecule EGFR tyrosine kinase inhibitors has the potential to prevent pulmonary fibrosis by inhibiting the proliferation of mesenchymal cells, and that targeting tyrosine kinase receptors might be useful for the treatment of pulmonary fibrosis in humans.</p>