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Arsenic is a potent toxic heavy metal found in the environment that can causes health problems, including liver disease in humans and animals. Chronic exposure to arsenic remains an environmental health problem worldwide, affecting hundreds of millions of people. Although the oxidative stress and apoptosis induced by arsenic have been confirmed, the underlying mechanism of apoptosis has not been fully elucidated. The purpose of this study is to investigate whether sodium arsenite (SA)induced liver toxicity is related to the regulation of DNA replication and repair pathways. The results of MTT and microscopy showed that SA has an inhibitory effect on the proliferation of human hepatocytes (L02), and this effect is time and concentration dependent. Flow cytometry detected the effects of different concentrations of SA on L02 cells. Compared with the control group, high concentrations of SA significantly affected the L02 cell cycle. In addition, RNA sequencing results showed that the differentially expressed genes in cells after SA treatment were concentrated in the DNA replication process and repair pathways. The effect of SA treatment on the expression of human RECQ DNA helicase and repair genes was further confirmed by Western blot and real-time quantitative PCR. In vitro study showed that SA treatment inhibited cell proliferation, and induced apoptosis as well as DNA damage and cell cycle arrest of human liver cell L02. Collectively, these results indicate that arsenic poisoning is related to the regulation of DNA replication and repair pathways, which provides insight for understanding the molecular mechanism of arsenic poisoning.
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Objective To investigate the effect of β1-Adrenoceptor autoantibody on liver function.Methods The biologically active of β1-AA was prepared and passive immunization model was established with β1-AA.The bio-chemical parameters of the liver were measured by the automatic serum biochemical analyzer.The liver size, hepatic vein,portal vein velocity were detected by liver ultrasound;hepatocytes apoptosis were tested by tunel stai-ning,annexin V/PI staining and caspase 3 activity detection.Results The biologically active of β1-AA and passive immunization model were established successfully.The ALT and AST of the liver significantly increased and the ALB decreased in the passive immunization process.The apoptosis of the hepatocytes increased,and meto-prolol partially reversed this effect.Conclusions β1-AA may induce hepatocytes apoptosis by β1-adrenergic receptor and participate in the development of liver injury.
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Objective To study the influence of radiation on autophagy and its protective effect on radiation injury of hepatic cells.Methods Autophagy in mouse liver tissues was examined by GFP-LC3 staining and Western blot.Radiation-induced hepatic injury was evaluated by ALT and AST in mouse serum,protein expressions,and H & E and TUNEL staining of liver tissue.L02 cells were used for in vitro study.Chloroquine and rapamycin were used to manipulate the level of autophagy.Results Total body irradiation (TBI) of 8 Gy caused an increase of autophagy in mouse liver tissue and AST level in serum (t =-7.47,P ＜0.05) at 12 h after irradiation.Irradiation significantly increased the apoptotic level in liver tissue as well.Inhibition of autophagy by chloroquine caused a further increases of AST [IR:(345.42±35.25)U/L vs.IR +CQ:(433.42 ±40.07)U/L,t =-2.86,P＜0.05] and ALT [IR:(35.67 ± 8.08) U/L vs.IR+CQ:(98.5±26.67)U/L,t=-3.09,P＜0.05] in the serum,and it also promoted apoptosis in live tissue.However,rapamycin as an autophagy promoter showed protective effect for radiation-induced hepatic injury [AST:IR:(345.42 ± 35.25) U/L vs.IR + Rap:(278.42 ± 20.09)U/L,t =-2.86,P ＜ 0.05].Similar changes of autophagy and apoptosis in L02 cells were also observed in the cells treated with chloroquine and rapamycin.Inhibition of autophagy by CQ caused an increase of ROS in vitro and in vivo and further increased ALT and AST levels in serum,reduced L02 cell viability.Activation of autophagy by Rap effectively reversed those changes.Conclusions Autophagy protects hepatic cells from radiation injury by decreasing ROS induction,which provides a potential target for the development of new clinical regimens against radiation induced liver injury.
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Objective To evaluate the effectiveness and safety of transarterial ehemoembolization(TACE) combined with radiofrequency ablation(RFA) and surgical resection(SR) in the treatment of early stage hepatocellular carcinoma(HCC).Methods PubMed,Medline,Embase,China biomedical database,Wanfang database,CQVIP database and Chinese Journal Full-text database were retrieved by computer.Prospective or retrospective studies of TACE combined with RFA and SR for treating early HCC published from January 2000 to March 2016 were collected.Results Four randomized or non-randomized concurrent controlled trials were included,involving 697 patients.The 1-year and 3-year overall survival(OS) rates in the TACE-RFA group were[94.40％(337/357) and 59.94％(214/357),which in the SR group were 92.35％(314/340) and 68.24％ (232/340),the difference between the two groups was not statistically significant(OR=1.43,95％CI:0.79-2.60,P=0.24,I2 =0％;OR=0.77,95％CI:0.56-1.07,P=0.12,I2 =45％).The 1-year relapse-free survival(RFS) rate of the TACE-RFA group and the SR group was similar [81.5％(291/357) vs.80.3％(273/340),OR=1.07,95％CI:0.73-1.57,P=0.74,I2=0％],while the 3-year RFSrate of the TACE-RFA group was obviously lower than that of the SR group(29.97％ vs.44.41％,OR=0.56,95％CI:0.40-0.77,P=0.000 5,I2 =0％).The incidence rate of severe complications in the TACE-RFA group was evidently lower than that in the SR group(1.43％ vs.5.07％,OR=0.23,95％CI:0.10-0.54,P=0.000 7,I2 =10％).Conclusion Compared with TACE-RFA,SR can significantly reduce the long term recurrence rate of early stage HCC,but the occurrence rate of severe complications in SR is higher than that in TACE-RFA.
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<p><b>OBJECTIVE</b>To find the signaling pathway of triptolide (TP)-induced liver injury and to reveal whether NF-E2-related factor 2 (Nrf2) plays an important role in cellular self-protection.</p><p><b>METHODS</b>The L-02 and HepG2 cells were cultured and treated with various concentrations of TP. The cell viability was observed, and the cell medium was collected for detecting the aspartate aminotransferase (ALT), alanine aminotransferase (AST), lactate dehydrogenase (LDH), superoxide dismutase (SOD) and L-glutathione production (GSH) levels. Nrf2 and its downstream target NAD(P)H: quinine oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1) expression, the nuclear translocation of Nrf2, and the binding ability of Nrf2 and antioxidant response element (ARE) were also identified. Meanwhile, shRNA was used to silence Nrf2 in L-02 cells to find out whether Nrf2 plays a protective role.</p><p><b>RESULTS</b>The viability of the L-02 and HepG2 cells treated with TP decreased in a doseand time-dependent manner, and TP (20-80 μg/mL) markedly induced the release of ALT, AST and LDH (P<0.05 or P<0.01), reduced the levels of SOD and GSH (P<0.01), and increased the intracellular reactive oxygen species. Meanwhile, TP augmented the Nrf2 expression in L-02 and HepG2 cells (P<0.05 or P<0.01), induced Nrf2 nuclear translocation, increased the Nrf2 ARE binding activity, and increased HO-1 and NQO1 expressions. Nrf2 knockdown revealed a more severe toxic effect of TP (P<0.05 or P<0.01).</p><p><b>CONCLUSIONS</b>Human hepatic cells treated with TP induced oxidative stress, and led to cytotoxicity. Self-protection against TP-induced toxicity in human hepatic cells might be via Nrf2-ARE-NQO1 transcriptional pathway.</p>
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Objectives To investigate the effects of sodium arsenite (NaAsO2) on the expression ot microRNA-191 (miR-191) and tissue inhibitor of metalloproteinase 3 (TIMP-3) in human normal hepatic cells (L-02 cells).Methods L-02 cells were exposed to different doses of NaAsO2 [0 (control group),5,25,50 and 75 μmol/L]for 24 h,or treated with 5 and 25 μmol/L NaAs02 for 0 (control group),12,24 and 48 h.The miR-191 inhibitor was used to suppress the expression of miR-191.qRT-PCR was performed to detect the expression level of miR-191 and TIMP-3 mRNA,and the protein level of TIMP-3 was analyzed by Western blotting.Results Dose-effect study:There were significant differences in the expressions of miR-191,TIMP-3 mRNA and protein between the 5 groups (F =85.674,20.952,123.393,all P ＜ 0.05).The expressions of miR-191 in all groups (1.702 ± 0.124,2.077 ±0.234,2.145 ± 0.105,2.003 ± 0.077) were higher than that of control group (0.990 ± 0.035,all P ＜ 0.05);the mRNA expressions of TIMP-3 in 25,50,75 μmol/L groups (0.848 ± 0.067,0.804 ± 0.081,0.813 ± 0.076) were all lower than that of control group (0.996 ± 0.007,all P ＜ 0.05),but there was no significant difference in the mRNA expression of TIMP-3 between the 5 μmol/L group and control group (0.939 ± 0.133 vs 0.996 ± 0.007,P＞ 0.05),and the protein expressions of TIMP-3 in all groups (0.846 ± 0.093,0.611 ± 0.123,0.554 ± 0.098,0.529 ± 0.067) were lower than that of control group (1.006 ± 0.003,all P ＜ 0.05).Time-effect study:there were significant differences in the expressions of miR-191,TIMP-3 mRNA and protein between the exposure groups of 5 and 25 μmol/L (For 5 μmol/L:F =86.355,16.404,22.898,all P ＜ 0.05;For 25 μmol/L:F =104.321,20.123,52.321,all P ＜ 0.05).The expressions of miR-191 in all exposure groups of 5 and 25 μmol/L (1.392 ± 0.152,1.691 ± 0.167,2.018 ± 0.130 and 1.456 ± 0.167,1.946 ± 0.178,2.259 ± 0.256) were higher than those of control groups (1.001 ± 0.014,1.008 ±0.027,all P ＜ 0.05);the mRNA expressions of TIMP-3 in 48 h exposure group of 5 μmol/L and all exposure groups of 25 μmol/L (0.824 ± 0.093 and 0.897 ± 0.033,0.815 ± 0.089,0.709 ± 0.103) were lower than those of control groups (1.004 ± 0.018,0.997 ± 0.057,all P ＜ 0.05),but there were no significant differences in the mRNA expressions of TIMP-3 between the 12,24 h exposure groups of 5 μmol/L and control group (0.952 ± 0.072,0.929 ± 0.121 vs1.004 ± 0.018,all P ＞ 0.05);the protein expressions of TIMP-3 in all exposure groups of 5 and 25 μmol/L (0.857 ±0.068,0.832 ± 0.106,0.691 ± 0.112 and 0.785 ± 0.097,0.620 ± 0.066,0.453 ± 0.075) were lower than those of control groups (1.006 ± 0.045,1.004 ± 0.078,all P ＜ 0.05).The treatment of miR-191 inhibitor:there were significant differences in the expressions of miR-191 and TIMP-3 protein between different groups (F =104.306,67.015,all P ＜ 0.05).The elevated expression level of miR-191 induced by NaAsO2 was significantly suppressed after transfected with miR-191 inhibitor (0.314 ± 0.094 vs 2.051 ± 0.371,P ＜ 0.05),which in turn up-regulated the protein expression of TIMP-3 (1.965 ± 0.277 vs 0.541 ± 0.183,P ＜ 0.05).Conclusion The expression level of miR-191 is elevated in response to NaAsO2 exposure,and miR-191 has subsequently suppressed the expression of TIMP-3,a potential target of miR-191.
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Objective To amplify four fragments of circumsporozoite ( CSP) protein gene from Plasmodium falciparum FCC1/HN strain and express recombinant CSP proteins in prokaryotic vector pET28 a/EGFP for further evaluation of their binding activities to hepatic cells .Methods Four pairs of primers were designed according to the cDNA sequence of CSP protein from Plasmodium falciparum FCC1/HN strain and used to amplify the gene fragments by PCR .The cloned gene fragments were inserted into pET28a/EGFP to construct the recombinant expression plasmids .The transformed E.coli BL21 strains carry-ing expression plasmids were induced by IPTG to express CPS proteins .The recombinant CSP proteins were purified with Ni2+chelating HiTrap HP column and detected by SDS-PAGE.The binding activities of the ex-pressed proteins to different tissues were also detected .Results Four gene fragments encoding CSP protein were successfully amplified and expressed in E.coil BL21 strain as fusion protein CSR1a-EGFP, CSR1b-EGFP, CSR2a-EGFP and CSR2b-EGFP with a relative molecular mass of about 39×103, 31×103, 33×103 and 30 ×10 3 , respectively .The purified fusion proteins reacted specifically with Plasmodium falciparum-posi-tive serum samples.Moreover, the recombinant protein CSR2a-EGFP could bind to the hepatic cells specif-ically rather than other cells.Conclusion The purified recombinant CSR2a-EGFP protein has a strong binding activity to hepatocytes , indicating its potential value as a targeting molecule for hepatic gene therapy .
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Objective To investigate the cause of differences in confluent growth between hepatic(L02) and hepatoma carcinoma(HCCLM3) cells by comparing responses of the two cells to different substrate stiffness (0.5, 4 kPa and glass). MethodsThe real-time photomicrography, immunofluorescence staining, flow cytometry, and Western Blotting techniques were respectively employed to observe the morphological characteristics, the cytoskeleton conformation and the distribution of E-cad of confluent L02 and HCCLM3 cells on different substrates, and test the changes in expression of E-cad, Integrinβ1 and p-Src. Results (1) Confluent L02 cells displayed a round or cubic shape, while HCCLM3 cells showed a polygon shape. The morphology of HCCLM3 cells were spread and polarized more obviously than that of L02 cells. With the increase of substrate stiffness, the variation of L02 cells with time was smaller than that of HCCLM3 cells. (2) The cytoskeleton of confluent L02 cells showed a ring-like conformation under the cortex, and E-cad was located at the cell-cell contact sites. However, the ring-like cytoskeleton of HCCLM3 cells was incomplete and distributed radially along the basement, while E-cad was dispersed in cytoplasm. (3) As the substrate stiffness increased, expression of E-cadherin in both L02 and HCCLM3 cells was significantly decreased (P<0.01), while the level of p-Src and integrinβ1 was increased significantly, with greater changes in HCCLM3 cells than in L02 cells. Conclusions The assembling of cortical ring-like cytoskeleton was positively correlated with the location of E-cad at the cell-cell contact sites. The substrate stiffness showed a more obvious impact on the balanced regulation between cadherin and integrin mediated adhesion system of hepatocarcinoma cells than that of hepatic cells.
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Objective To investigate the cause of tumor cell migration by comparing the effect of substrate stiffness on hepatic and hepatoma carcinoma cell migration so as to understand the invasive characteristics of tumor cells. Methods Immunofluorescence staining, morphological analysis and transwell were employed to observe the morphological characteristics of HCCLM3 and L02 cells on different substrates and test their migration characteristics with the quantitative analysis. Results (1) The migration rate and net translocation of HCCLM3 and L02 cells on 4 kPa substrate was higher than those both on 0.5 kPa(most soft one) and on glass (the hardest one) substrates, and L02 cells also displayed higher migration efficiency than HCCLM3 cells on such substrates. (2) The mean squared displacement of HCCLM3 and L02 cells on different substrates showed consistent tendency, and the directional persistence of L02 cells on the softer substrate was significantly higher than that of HCCLM3 cells. (3) In 0.5 and 1 mg/mL three dimensional collagen environment, the number of invasive cells of HCCLM3 was remarkably more than that of L02 cells. After adding MMPs inhibitor GM6001 (40 μg/mL), the number of invasive cells was notably increased in HCCLM3 cells, but notably decreased in L02 cells. Conclusions (1) In two dimensional comparatively soft environment, L02 cells displayed an efficient migration due to its higher directional persistence. (2) In three-dimensional collagen environment, the invasion efficiency of HCCLM3 cells was significantly higher due to the various modes of migration adaptation to the microenvironment.