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Objective To investigate the radioprotective function and its mechanism of miR-223 in acute radiation-induced lung injury in mice.Methods Forty female C57BL/6 J mice were randomly divided into healthy control group,irradiation group,irradiation plus miR-223 group and irradiation plus NC group.Radiation groups were exposed with a single dose of 15 Gy of 6 MV X-rays delivered by a linear accelerator.The mice in drug group were administered by tail vein injection with miR-223 agomir or agomirNC every other day from 1 d before irradiation to 14 d after irradiation.The lung tissue samples of mice were taken at 14 d post-irradiation.The pathological changes were observed by HE staining.The localization and expressions of IL-1β and IL-18 were observed by immunohistochemistry (IHC).Real-time PCR was used to detect miR-223,but NLRP3 mRNA expression in lung tissue.Western blot was used to detect the protein expressions of NLRP3 and Caspase-1,and ELISA assay was used to detect the expressions of IL-1β and IL-18 in lung homogenate.Results Radiation decreased the expression of miR-223,but increased the expression of NLRP3 in lung tissue.Administration of miR-223 agomir inhibited the expression of NLRP3 and attenuated lung inflammation.HE and IHC staining showed that miR-223 reduced the acute inflammatory response and the expressions of IL-1β and IL-18 in lung tissue compared with irradiation group (t=10.16,6.00,P＜0.05).The expressions of NLRP3 and Caspase-1 protein in lung tissue of irradiated plus miR-223 group was lower than that in the irradiation alone group (t =12.47,4.95,P＜ 0.05).ELISA assay also showed a decrease of inflammatory factors IL-1β and IL-18 in lung tissue homogenate of the irradiation plus miR-223 group (t =8.22,8.47,P＜0.05).Conclusions MiR-223 effectively reduces the secretion of radiation-induced inflammatory factors IL-1β and IL-18 by inhibiting the expression of NLRP3 in lung tissue of mice,and thus has protective effect on radiation-induced lung injury.
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Objective@#To explore the value of plasma cell-free DNA (cfDNA) in the assessment of inflammatory bowel disease (IBD) activity. @*Methods@#From July 2014 to June 2017, 145 IBD patients from the First Affiliated Hospital of Fujian Medical University were selected. The plasma content of cfDNA was detected by picogreen-based fluorescent quantitative method. At the same period, 37 healthy individuals were enrolled as control group. The correlation between cfDNA content and C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and IBD activity was analyzed. The diagnostic capability of cfDNA in IBD activity was assessed by the receiver operating characteristic (ROC) curve. T-test was performed for comparison between two independent samples, and Pearson correlation coefficient test was used for correlation analysis between two variants. @*Results@#The content of plasma cfDNA of patients with Crohn′s disease (CD) and patients with ulcerative colitis (UC) were (29.17±2.07) μg/L and (26.86±1.97) μg/L, respectively; which were both higher than those of healthy control group (21.10±1.02) μg/L, and the differences were statistically significant (t=2.609 and 2.082, both P<0.05). Moreover, the content of cfDNA of patients with active CD or UC were (35.72±3.26) μg/L and (32.37±3.42) μg/L, respectively, which were both higher than those of patients with CD or UC in remission ((21.12±1.43) μg/L and (20.82±1.02) μg/L), and the differences were statistically significant (t=3.806 and 3.116, both P<0.01). The cfDNA content of CD patients was positively correlated with CRP, ESR and disease activity (r=0.555, 0.393 and 0.400, all P<0.01). The cfDNA content of UC patients was also positively correlated with CRP, ESR and disease activity (r=0.640, 0.421 and 0.360, all P<0.01). The diagnostic capability of the combination of CRP and ESR was the highest in CD diagnosis, with the area under curve (AUC) value being 0.841, and the sensitivity and specificity being 81.4% and 74.3%, respectively. The diagnostic capability of the combination of cfDNA, CRP and ESR was the highest in UC diagnosis, with the AUC value being 0.851, and the sensitivity and specificity being 74.3% and 96.9%, respectively. @*Conclusions@#Increased cfDNA levels in IBD patients are correlated with IBD activity. Detection of cfDNA is helpful in the identification of active IBD, and the combination of ESR and CRP can improve the diagnostic efficiency of UC.
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Objective@#To investigate the effect of ubiquitous mitochondrial creatine kinase 1(CKMT1) on the sensitivity of human nasopharyngeal carcinoma cell line CNE-1 to DDP. @*Methods@#CNE-1 cells were transiently transfected with CKMT1 overexpression (CKMT1) or empty vector (EV). The growth curve and DDP IC50 were developed by MTT assay, plate clone formation assay was performed by gradient concentration of DDP treatment, cell cycle and apoptosis were detected by flow cytometry, levels of apoptosis related protein Bax/Bcl-2/C-PARP and the transcription factor p-STAT3-Tyr705 were detected by Western Blot. @*Results@#The transfection efficiencies of CKMT1 and EV were more than 90% with a higher proliferation rate in the CKMT1-transfected cells. However, the CKMT1-transfected cells had a DDP IC50 of 2.76 μmol/L, which was significantly lower than that of 4.60 μmol/L in the EV-transfected cells (P<0.01). With the treatment of certain concentration of DDP, the CKMT1-transfected cells had a lower clone formation rate, the cell cycle arrested more obviously in G2/M phase, and the apoptosis rate was higher (P<0.01), with higher levels of Bax/C-PARP (P<0.05 or P<0.01), but lower levels of Bcl-2 (P<0.01) and p-STAT3-Tyr705 (P<0.01), compare with the EV-transfected cells. @*Conclusions@#CKMT1 may inhibit the activation of STAT3, increasing the sensitivity of CNE-1 to chemotherapeutic drug DDP.
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ObjectiveTo explore the endocytic pathway of TAT-LHRH modified chitosan/DNA nanoparticle (TLCDN) that exhibits high transfection efficiency and targeting to HepG2.MethodsPlasmid DNA was labeled with fluorescein,and the resulting fluorescent DNA was complexed with chitosan or TAT-LHRH modified chitosan to form chitosan/DNA nanoparticle (CDN) and TLCDN by the complex coacervation method.Internalization of TLCDN or CDN by HepG2 cells were measured in the presence of three kinds of inhibitors of endocytic pathway,Chlorpromazine,Filipin or Dynasore,using High-Content Analyzer to collect and analyze the data.ResultsChlorpromazine led to more decreased uptake of CDN than that of TLCDN,although not statistically significant.Filipin demonstrated significant inhibitory effect on the uptake of TLCDN while promoted the uptake of CDN.Dynasore resulted in a similar decrease in the uptake of both nanoprticles.ConclusionIt was demonstrated that CDN was taken up by HepG2 cells mainly through the clathrin-dependent endocytic pathway and TLCDN was more likely to be internalized by HepG2 cells through the caveolin-mediated endocytic pathway although the clathrin-dependent endocytic pathway was also involved.