ABSTRACT
ObjectiveA good invasion ability of extravilloustrophoblas (EVTs) is the prerequisite for successful placental colonization and effective remodeling of the uterine spiral artery. This article aims to simulate the pathophysiological process of oxidative stress inducing trophoblasts to pyroptosis in vitro, exploring the correlation between trophoblasts pyroptosis and the pathogenesis of preeclampsia.MethodsTwenty-five patients with preeclampsia were selected from the Department of Obstetrics and Gynecology, Zhongda Hospital affiliated to Southeast University from September 2017 to January 2019. Among them, early-onset preeclampsia (gestational weeks<34) was early-onset group (n=17), late-onset preeclampsia (gestational weeks≥34) was late-onset group (n=8), and full-term pregnant women with normal blood pressure (39＜gestational weeks＞42) were selected as normal group (n=10). Human trophoblasts were cultured with HTR-8/SVneo for 12 hours, and then treated with H2O2 (100, 150, 200, 250μmol/L) (2, 4, 6, 12 h), to induce human trophoblast HTR-8/SVneo pyrolysis model; the control group was normal cultured cells of 1640+10% fetal bovine serum + 1% antibiotics. Placental specimens from 7 patients with preeclampsia were randomly selected, including 3 cases in early onset group, 4 cases in late onset group and 1 case in normal group. The total proteins of cells and placenta were extracted respectively, and the expression of scorch death-related molecular proteins was detected. The mRNA levels of pyroptosis related molecules in cells was detected by RT-qPCR, and the morphological changes of cells were observed by inverted phase contrast microscope.ResultsThe Western blot results showed that the activation of the key molecular activation form of the cell pyrogenesis pathway, Cleaved caspase1, could be detected in the placenta. When H2O2 was 150 mol/L for 2h, the mRNA levels of NLRP3 and IL-1, the key molecules of the upstream activation signal, were significantly up-regulated (8.680±0.481, 14.136±0.244) compared with the control group (1.00±0.00) (P<0.000). At 4h, mRNA levels of key molecule GSDMD and downstream inflammatory factor IL-18 (1.639±0.354 and 1.794±0.043) in the pyrogenesis pathway were significantly higher than those in the control group (1.00±0.00), with statistically significant differences (P<0.05). By reverse validation of the mRNA levels of the molecules associated with pyroptosis, the optimal conditions of the model induced by H2O2 were 150 mol/L and 4h, and the typical changes, such as cell swelling, fragmentation and plasma membrane bubble formation, could be seen under the light microscope.ConclusionThe pyroptosis model of trophoblast cells was successfully established, and the physiological process of oxidative stress inducing trophoblasts to pyroptosis in vitro was successfully simulated, providing new ideas and directions for the diagnosis and treatment of preeclampsia and the development of new drugs.
ABSTRACT
Japanese encephalitis virus (JEV) is a pathogenic mosquito-borne flavivirus which is responsible for outbreaks of severe viral encephalitis. The cellular entry of JEV is a prerequisite for Japanese encephalitis, so the understanding of its underlying mechanisms will provide more approaches for treating such disease. In recent years, increasing research has been conducted to investigate the mechanisms of cellular entry of JEV, and the results of research on other flavivirus have expanded the research directions for JEV. More methods will be used to suppress JEV infection because of the development of E protein antibodies and the discovery of several inhibitors of the cellular entry process. This review will summarize the recent advances in the mechanisms of JEV cellular entry and membrane fusion.
Subject(s)
Animals , Humans , Biomedical Research , Encephalitis Virus, Japanese , Genetics , Physiology , Encephalitis, Japanese , Virology , Virus InternalizationABSTRACT
<p><b>BACKGROUND</b>Aberrant DNA methylation plays a key role in human carcinogenesis. 5-aza-2'-deoxycytidine inhibits DNA methylation and induces the expression of genes putatively silenced by promoter methylation in vitro. There are few studies of the biological and clinical significance of 5-aza-2'-deoxycytidine in human hepatocellular carcinoma. This study explored the mechanism of 5-aza-2'-deoxycytidine targeting transcriptional repressor complexes affecting global gene expression in hepatocellular carcinoma cell line.</p><p><b>METHODS</b>High density oligonucleotide gene expression microarrays were used to examine the effects of 5-aza-2'-deoxycytidine treatments on human hepatocellular carcinoma cell line SMMC-7721. The 5' ends of the genes upregulated or downregulated in this manner were compared with BLAST database to determine whether they might have promoter CpG islands. Flow cytometry was used to detect stages of the cell cycle and apoptosis of SMMC-7721 after being treated with 5-aza-2'-deoxycytidine.</p><p><b>RESULTS</b>Data obtained 3 days after 4 days of treatment with 5-aza-2'-deoxycytidine showed that more genes were induced in tumorigenic cells including genes that function in cell proliferation, differentiation, regulation of transcription, and cytokine signalling. Approximately 30% of induced genes did not have CpG islands within their 5' regions, suggesting that some genes activated by 5-aza-2'-deoxycytidine may not result from the direct inhibition of promoter methylation. This phenomenon may contribute to a number of upregulated genes involving regulation of transcription in the treated cell. Results showed that 100 micromol/L 5-aza-2'-deoxycytidine blocked cell cycle at S/G2-M phase increasing rate of apoptosis. Notably, we found differential expression of molecular action in the methylation although DNA methyltransferases did not show significant difference in the treated cell line.</p><p><b>CONCLUSION</b>5-aza-2'-deoxycytidine could restore some silenced genes expression independently of DNA methylation inhibition and expression of DNA methyltransferases.</p>