AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate...AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate at the ratio of 2:1) for 24 h.Cytotoxicity and apoptosis were evaluated by 3-(4,5-dmethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and Annexin V/propidium iodide staining,respectively.Cellular total lipid was determined using a photocolorimetric method after Nile red staining,and triglyceride content was measured using an enzymatic kit.To study the effects of Sch B on steatosis,L-02 cells were treated with Sch B (1-100 μmol/L) in the absence or presence of 1 mmol/L FFA for 24 h,and cellular total lipid and triglyceride levels were measured.To explore the mechanisms of action of Sch B in the steatotic L-02 cells,mRNA levels of several regulators of hepatic lipid metabolism including adipose differentiation related protein (ADRP),sterol regulatory element binding protein 1 (SREBP-1),peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ were measured by quantitative real-time polymerase chain reaction (PCR),and protein levels of ADRP and SREBP-1 were measured by immunoblotting.RESULTS:Treatment with 1 mmol/L FFA for 24 h induced intracellular lipid accumulation in L-02 cells comparable to that in human steatotic livers without causing apparent apoptosis and cytotoxicity.Sch B mitigated cellular total lipid and triglyceride accumulations in the steatotic L-02 cells in a dose-dependent manner.Quantitative real-time PCR and Western blot analyses revealed that treatment of L-02 cells with 100 μmol/L Sch B reverted the FFA-stimulated up-regulation of ADRP and SREBP-1.CONCLUSION:Sch B inhibits FFA-induced steatosis in L-02 cells by,at least in part,reversing the up-regulation of ADRP and SREBP-1.展开更多
HSV-1 infection-mediated regulation of mRNA translation in host cells is a systematic and complicated process. Investigation of the details of this mechanism will facilitate understanding of biological variations in t...HSV-1 infection-mediated regulation of mRNA translation in host cells is a systematic and complicated process. Investigation of the details of this mechanism will facilitate understanding of biological variations in the viral replication process and host cells. In this study, a comparative proteomics technology platform was applied by two-dimension electrophoresis of HSV-1 infected normal human L-02 cell and control cell lysates. The observed protein spots were analyzed qualitatively and quantitatively by the PDQuest software package. A number of the different observed protein spots closely associated with cellular protein synthesis were identified by matrix-assisted laser-desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The expression levels of the RPLP1 protein, which is required for mRNA translation, and KHSRP protein, which is involved in rapid decay of mRNA, were up-regulated, whereas the expression level of RNP H2, which is involved in positive regulation on the mRNA splicing process, was down-regulated. All of these results suggest that HSV-1 infection can influence cellular protein synthesis via modulation of cellular regulatory proteins involved in RNA splicing, translation and decay, resulting in optimisation of viral protein synthesis when cellular protein synthesis is shut off. Although there is need for further investigations regarding the detailed mechanisms of cellular protein control, our studies provide new insight into the targeting of varied virus signaling pathways involved in host cellular protein synthesis.展开更多
Trichloroethylene （TCE） is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TC...Trichloroethylene （TCE） is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TCE cytotoxicity have been made in cultured liver cells. However, the molecular mechanisms by which TCE induces hepatotoxicity are not well understood. SET （also known as protein phosphatase 2A inhibitor, 12PP2A, or template-activating factor-I, TAF-D is a nuclear protein that regulates histone modification, gene transcription, DNA replication, nucleosome assembly,展开更多
[Objectives] To study the protection of compatibility of Saikosapon d and Baicalin on carbon tetrachloride( CCl_4) injured L-02 cells. [Methods] Normal human hepatocyte cell line L-02 cells were cultured in vitro,and ...[Objectives] To study the protection of compatibility of Saikosapon d and Baicalin on carbon tetrachloride( CCl_4) injured L-02 cells. [Methods] Normal human hepatocyte cell line L-02 cells were cultured in vitro,and CCl_4 was used to induce hepatocellular injury. Interventions were carried out with Saikosaponin d and Baicalin at different dosage. The proliferation of L-02 cells in each group was determined by methylthiazolyl tetrazolium( MTT) assay; the levels of AST and ALT in the culture supernatants were detected by enzyme-linked immunosorbent assay( ELISA); the expressions of TLR4 and NFκBp65 proteins in each group were determined by immunohistochemistry.[Results] In the CCl_4 injured group,the proliferation of L-02 cells was significantly declined,the levels of AST and ALT in cell culture medium were significantly increased,and the expressions of TLR4 and NFκBp65 in L-02 cells were increased; after the intervention of Saikosaponin d and Baicalin,1. 75 μg/mL group and 1. 5 μg/mL group had an effect of promoting the proliferation of L-02 cells and could reduce the levels of AST and ALT in the cell culture medium,and TLR4 and NFκBp65 proteins in L-02 cells also had a certain inhibitory effect. [Conclusions] The compatibility of Saikosapon d and Baicalin has a certain protective effect on CCl_4 injured L-02 cells. The protection mechanism may be related with its down-regulating TLR4-NFκB signaling pathway and reducing the inflammation.展开更多
Objective： To detect differential protein expression in malignant and normal liver cell lines in vitro using the SELDI ProteinChip platform, for investigating the pathogenesis of liver cancer. Methods： Two cell line...Objective： To detect differential protein expression in malignant and normal liver cell lines in vitro using the SELDI ProteinChip platform, for investigating the pathogenesis of liver cancer. Methods： Two cell lines, human normal liver cell line L02 and hepatoma cell line SMMC-7721 were cultured routinely, harvested in good condition and lysed. After quantification, the supernatant of the lysate was tested by IMAC3 （Immobilized Mental Affinity Capture） and WCX2 （Weak Cation Exchange） chips on the SELDI-TOF-MS ProteinChip reader. Results： Protein expression differed between the malignant and normal liver cell lines. A total of 20 differentially expressed proteins were found, among which, 7 were captured by the IMAC3 chip and 14 by the WCX2 chip. Peaks at 5,419, 7,979 and 11,265 Da were higher and at 8,103, 8,492, 10,160 and 11,304 Da lower in SMMC-7721 cells by the IMAC3 chip; peaks at 7,517, 7,945 and 7,979 Da were higher and at 5,061, 5,551, 5,818, 7,439, 9,401,10,100, 10,312, 11,621, 11,662, 11,830 and 12,772 Da lower in SMMC-7721 cells by the WCX2 chip. Interestingly, both chips captured the 7,979 Da peak. In addition, the 11,081 Da peak corresponded precisely with the molecular mass of the calcium binding protein S100A10, which may participate in the formation of liver cancer in association with p36. Conclusion： Detecting differential protein expression in malignant and normal liver cell lines using the SELDI ProteinChip platform was simple, sensitive and repeatable. The results we obtained can serve as a basis for investigating the pathogenesis of liver cancer and aid the discovery of new therapeutic targets.展开更多
Objective To investigate the effects of sodium arsenite（NaAsO2）on the expression of microRNA-191（miR-191）and tissue inhibitor of metalloproteinase 3（TIMP-3）in human normal hepatic cells（L-02 cells）.Methods L-0...Objective To investigate the effects of sodium arsenite（NaAsO2）on the expression of 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 Na2As O2[0（control group）,5,25,50 and 75μmol/L]展开更多
目的研究莲房原花青素(LSPC)对乙醇诱导的人胚肝细胞株L-02凋亡的拮抗作用机制。方法观察5、10、25mg/L的LSPC与200mmol/L乙醇共同作用于肝细胞L-0224h后,对细胞生存率、凋亡率的影响,对细胞凋亡通路的相关基因MAPK38、Caspase3、p53以...目的研究莲房原花青素(LSPC)对乙醇诱导的人胚肝细胞株L-02凋亡的拮抗作用机制。方法观察5、10、25mg/L的LSPC与200mmol/L乙醇共同作用于肝细胞L-0224h后,对细胞生存率、凋亡率的影响,对细胞凋亡通路的相关基因MAPK38、Caspase3、p53以及生长抑制DNA损伤诱导基因(growth arrest and DNA damage-in-ducible gene,GADD)GADD34、GADD45β、GADD153表达的影响。结果与乙醇组相比,5mg/L和10mg/LLSPC使细胞的生存率由73.14%上升到84.79%和90.52%,通过抑制细胞p53和Caspase3通路,并通过降低DNA损伤而降低GADD34、GADD45β、GADD153的表达(P<0.01),从而有效降低细胞的凋亡率,从11.54%分别降至8.21%和9.10%(P<0.05);抑制凋亡率的效果以LSPC5mg/L组最佳,10mg/L组效果次之,但高剂量组(25mg/L)对乙醇所致凋亡的拮抗作用不明显,对细胞生存率也无影响。乙醇和LSPC处理均不影响L-02细胞的MAPK38表达。结论适当浓度的莲房原花青素对乙醇诱导的肝细胞L-02的凋亡有拮抗作用。其抑制凋亡的作用主要是通过p53、Caspase3和GADD途径,而与MAPK途径无关。展开更多
基金Supported by The Hong Kong Baptist University,No.FRG 08-09/II-30
文摘AIM:To investigate the effects of schisandrin B (Sch B) on free fatty acid (FFA)-induced steatosis in L-02 cells.METHODS:Cellular steatosis was induced by incubating L-02 cells with a FFA mixture (oleate and palmitate at the ratio of 2:1) for 24 h.Cytotoxicity and apoptosis were evaluated by 3-(4,5-dmethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and Annexin V/propidium iodide staining,respectively.Cellular total lipid was determined using a photocolorimetric method after Nile red staining,and triglyceride content was measured using an enzymatic kit.To study the effects of Sch B on steatosis,L-02 cells were treated with Sch B (1-100 μmol/L) in the absence or presence of 1 mmol/L FFA for 24 h,and cellular total lipid and triglyceride levels were measured.To explore the mechanisms of action of Sch B in the steatotic L-02 cells,mRNA levels of several regulators of hepatic lipid metabolism including adipose differentiation related protein (ADRP),sterol regulatory element binding protein 1 (SREBP-1),peroxisome proliferator-activated receptor (PPAR)-α and PPAR-γ were measured by quantitative real-time polymerase chain reaction (PCR),and protein levels of ADRP and SREBP-1 were measured by immunoblotting.RESULTS:Treatment with 1 mmol/L FFA for 24 h induced intracellular lipid accumulation in L-02 cells comparable to that in human steatotic livers without causing apparent apoptosis and cytotoxicity.Sch B mitigated cellular total lipid and triglyceride accumulations in the steatotic L-02 cells in a dose-dependent manner.Quantitative real-time PCR and Western blot analyses revealed that treatment of L-02 cells with 100 μmol/L Sch B reverted the FFA-stimulated up-regulation of ADRP and SREBP-1.CONCLUSION:Sch B inhibits FFA-induced steatosis in L-02 cells by,at least in part,reversing the up-regulation of ADRP and SREBP-1.
基金National Natural Science Funds (30570081 and 30670094)
文摘HSV-1 infection-mediated regulation of mRNA translation in host cells is a systematic and complicated process. Investigation of the details of this mechanism will facilitate understanding of biological variations in the viral replication process and host cells. In this study, a comparative proteomics technology platform was applied by two-dimension electrophoresis of HSV-1 infected normal human L-02 cell and control cell lysates. The observed protein spots were analyzed qualitatively and quantitatively by the PDQuest software package. A number of the different observed protein spots closely associated with cellular protein synthesis were identified by matrix-assisted laser-desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The expression levels of the RPLP1 protein, which is required for mRNA translation, and KHSRP protein, which is involved in rapid decay of mRNA, were up-regulated, whereas the expression level of RNP H2, which is involved in positive regulation on the mRNA splicing process, was down-regulated. All of these results suggest that HSV-1 infection can influence cellular protein synthesis via modulation of cellular regulatory proteins involved in RNA splicing, translation and decay, resulting in optimisation of viral protein synthesis when cellular protein synthesis is shut off. Although there is need for further investigations regarding the detailed mechanisms of cellular protein control, our studies provide new insight into the targeting of varied virus signaling pathways involved in host cellular protein synthesis.
基金supported by NSFC (the National Natural Science Foundation of China) [81273126, 30972454]the Key Project of Guangdong Natural Science Foundation [S2012020010903]+2 种基金the Project of Shenzhen Basic Research Plan [JCYJ20120616 154222545]the Upgrade Scheme of Shenzhen Municipal Key Laboratory [CXB201005260068A]Medical Scientific Research Foundation of Guangdong Province (A2012577)
文摘Trichloroethylene （TCE） is a major pollutant that affects both occupational and general environments. The liver is an important target organ of TCEE. Substantial efforts and remarkable progress into understanding TCE cytotoxicity have been made in cultured liver cells. However, the molecular mechanisms by which TCE induces hepatotoxicity are not well understood. SET （also known as protein phosphatase 2A inhibitor, 12PP2A, or template-activating factor-I, TAF-D is a nuclear protein that regulates histone modification, gene transcription, DNA replication, nucleosome assembly,
基金Supported by Project of Shaanxi Administration of Traditional Chinese Medicine(zy06)Special Project of Education Department of Shaanxi Provincial Government(12JK1016)Program of Shaanxi Provincial Department of Science and Technology(2013jk4023)
文摘[Objectives] To study the protection of compatibility of Saikosapon d and Baicalin on carbon tetrachloride( CCl_4) injured L-02 cells. [Methods] Normal human hepatocyte cell line L-02 cells were cultured in vitro,and CCl_4 was used to induce hepatocellular injury. Interventions were carried out with Saikosaponin d and Baicalin at different dosage. The proliferation of L-02 cells in each group was determined by methylthiazolyl tetrazolium( MTT) assay; the levels of AST and ALT in the culture supernatants were detected by enzyme-linked immunosorbent assay( ELISA); the expressions of TLR4 and NFκBp65 proteins in each group were determined by immunohistochemistry.[Results] In the CCl_4 injured group,the proliferation of L-02 cells was significantly declined,the levels of AST and ALT in cell culture medium were significantly increased,and the expressions of TLR4 and NFκBp65 in L-02 cells were increased; after the intervention of Saikosaponin d and Baicalin,1. 75 μg/mL group and 1. 5 μg/mL group had an effect of promoting the proliferation of L-02 cells and could reduce the levels of AST and ALT in the cell culture medium,and TLR4 and NFκBp65 proteins in L-02 cells also had a certain inhibitory effect. [Conclusions] The compatibility of Saikosapon d and Baicalin has a certain protective effect on CCl_4 injured L-02 cells. The protection mechanism may be related with its down-regulating TLR4-NFκB signaling pathway and reducing the inflammation.
基金the grant from the National Natural Science Foundation of China(No.30471527, No. 30540075)Mt. Tai Scholar Construction Engineering Foundation
文摘Objective： To detect differential protein expression in malignant and normal liver cell lines in vitro using the SELDI ProteinChip platform, for investigating the pathogenesis of liver cancer. Methods： Two cell lines, human normal liver cell line L02 and hepatoma cell line SMMC-7721 were cultured routinely, harvested in good condition and lysed. After quantification, the supernatant of the lysate was tested by IMAC3 （Immobilized Mental Affinity Capture） and WCX2 （Weak Cation Exchange） chips on the SELDI-TOF-MS ProteinChip reader. Results： Protein expression differed between the malignant and normal liver cell lines. A total of 20 differentially expressed proteins were found, among which, 7 were captured by the IMAC3 chip and 14 by the WCX2 chip. Peaks at 5,419, 7,979 and 11,265 Da were higher and at 8,103, 8,492, 10,160 and 11,304 Da lower in SMMC-7721 cells by the IMAC3 chip; peaks at 7,517, 7,945 and 7,979 Da were higher and at 5,061, 5,551, 5,818, 7,439, 9,401,10,100, 10,312, 11,621, 11,662, 11,830 and 12,772 Da lower in SMMC-7721 cells by the WCX2 chip. Interestingly, both chips captured the 7,979 Da peak. In addition, the 11,081 Da peak corresponded precisely with the molecular mass of the calcium binding protein S100A10, which may participate in the formation of liver cancer in association with p36. Conclusion： Detecting differential protein expression in malignant and normal liver cell lines using the SELDI ProteinChip platform was simple, sensitive and repeatable. The results we obtained can serve as a basis for investigating the pathogenesis of liver cancer and aid the discovery of new therapeutic targets.
文摘Objective To investigate the effects of sodium arsenite（NaAsO2）on the expression of 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 Na2As O2[0（control group）,5,25,50 and 75μmol/L]
文摘目的研究莲房原花青素(LSPC)对乙醇诱导的人胚肝细胞株L-02凋亡的拮抗作用机制。方法观察5、10、25mg/L的LSPC与200mmol/L乙醇共同作用于肝细胞L-0224h后,对细胞生存率、凋亡率的影响,对细胞凋亡通路的相关基因MAPK38、Caspase3、p53以及生长抑制DNA损伤诱导基因(growth arrest and DNA damage-in-ducible gene,GADD)GADD34、GADD45β、GADD153表达的影响。结果与乙醇组相比,5mg/L和10mg/LLSPC使细胞的生存率由73.14%上升到84.79%和90.52%,通过抑制细胞p53和Caspase3通路,并通过降低DNA损伤而降低GADD34、GADD45β、GADD153的表达(P<0.01),从而有效降低细胞的凋亡率,从11.54%分别降至8.21%和9.10%(P<0.05);抑制凋亡率的效果以LSPC5mg/L组最佳,10mg/L组效果次之,但高剂量组(25mg/L)对乙醇所致凋亡的拮抗作用不明显,对细胞生存率也无影响。乙醇和LSPC处理均不影响L-02细胞的MAPK38表达。结论适当浓度的莲房原花青素对乙醇诱导的肝细胞L-02的凋亡有拮抗作用。其抑制凋亡的作用主要是通过p53、Caspase3和GADD途径,而与MAPK途径无关。
