Objective: To investigate the inhibitory effect of Rh2 on HepG2 cells and explore the underlying mechanism.Methods: We used lentivirus carrying β-catenin to infect HepG2 cell, and detected expression of β-catenin using fluorescence microscopy.The effect of Rh2 on proliferation of HepG2-β-catenin and HepG2 cells was measured by CKK-8 assay,and flow cytometry was used to detect cell cycle and apoptosis.The activity of Gsk-3βwas checked by ELISA kit.The expression of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 genes were measured by qRT-PCR.In order to checked the relationship between β-catenin and TCF4,CHIP assay kit was used,the expression of Bax,Bcl2,CyclinD1,MMP3 genes were measured by PCR.The expressions of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 proteins were examined by Western blot.Results:HepG2 cells were successfully infected by pLOV-EF1a-MCS-3FLAG-β-catenin lentivirus,named HepG2-β-catenin.CCK-8 showed that ginsenoside Rh2 could effectively inhibit the proliferation of HepG2 and HepG2-β-catenin cells in vitro,which exhibits a dose-dependent manner at range of 10-160 μmol/L Rh2.The IC50 of Rh2 exposure on HepG2 cell for 48,72 h were 100 μmol/L and 58.12 μmol/L,but the IC50 of Rh2 exposure on HepG2-β-catenin for 48,72 h were 129.2 μmol/L,83.33 μmol/L,respectively.The IC50 of Rh2 exposure on HepG2-β-catenin cell was higher than HepG2 cell, compared with HepG2 group the differences was statistically significant ( P<0.01 ).Flow cytometry indicated that Rh2 could arrest HepG2 and HepG2-β-catenin cells in G0/G1 phase;the cell population in G0/G1 phase of HepG2+Rh2 group was(64.57±0.65)%,HepG2-β-catenin+Rh2 group was(58.61±2.01)%.Flow cytometry indicated that Rh2 could induced early apoptosis in HepG2 and HepG2-β-catenin cells.The apoptosis rate of HepG2 +Rh2 group was (17.27 ±2.77)%,HepG2-β-catenin +Rh2 group(9.02 ±1.76)%.The ELISA results indicated that HepG2 cells was induced by Rh2 for 12,24,48,72 h,the activity of Gsk-3βgradually increased,peak in 48 h,then decreased.Compared with control group,Rh2 induced HepG2 and HepG2-β-catenin cells for 48 hours, Gsk-3βactivity were increased, and their activity reduced after adding Bio, there were no significant differences between HepG2+Rh2 and HepG2-β-catenin+Rh2 groups.The PCR,CHIP and WB results showed that the expression of Gsk-3β,Bax gene and proteins increased,while theβ-catenin,CyclinD1,Bcl2,MMP3 gene and proteins down-regulation in HepG2 and HepG2-β-catenin cell induced by Rh2.Compared with HepG2-β-catenin +Rh2 group, the expression of other gene and proteins changed significantly,however,Gsk-3βwas no significant difference.Conclusion:Over-expression of β-catenin may weaken the phar-macological effects of ginsenoside Rh2 on HepG2 cells.The activity of Gsk-3βwas increased by ginsenoside Rh2 to degradeβ-catenin, affecting the expression of downstream genes,promoting apoptosis of liver cancer cells and inhibiting metastasis.

Objective:To study the mechanism of ginsenoside Rh2 inhibiting HepG2 cells migration.Methods:HepG2 cells in logarithmic growth phase were cultured in 96-well plates,which were induced by different concentration Rh2,respectively for 24,48,72 hours.The cell inhibition was detected by Cell Counting Kit.Transwell chambers was used to checked HepG2 cell migration ability;luciferase was tested by Luciferase Reporter Assay system reagent;The expressions of P-ERK,ERK,P-P38,P-38,P-JUK,JUK,MMP3 proteins were detect by Western blot;the expression of AP1,MMP3 gene were detected by Quantitative PCR;The expression of AP1, MMP3 fluorescence protein were observed by fluorescence microscopy.Results:Administrated with different concentration of Rh2 after 24 ,48 ,72 h,the proliferation of HepG2 cells were inhibited ( P<0.05) ,and in dose-and time-dependent manner.Transwell assay showed Rh2 could significantly inhibited migration of HepG2 cells.The expressions of P-ERK , MMP3 proteins were significantly decreased,the expressions of P-JUK, P-P38 proteins were significantly increased, expression levels of ERK, P-38, JUK were no significant difference.Expression of AP1,MMP3 gene were significantly decreased,the expressions of AP1,MMP3 fluorescence proteins were significantly decreased.Conclusion:Ginsenoside Rh2 can activate MAPK pathway to inhibit the migration of HepG2 cells.

OBJECTIVETo investigate the role of phospholipid transfer protein (PLTP) in cigarette smoke extract (CSE)-induced apoptosis of rat alveolar type II cells (RLE-6TN) in vitro.

METHODSRat alveolar epithelial cell line RLE-6TN were transfected with a small interfering RNA (siRNA) targeting PLTP prior to exposure to different concentrations of CSE for 24 or 48 h. The morphological changes of the apoptotic cells were observed by fluorescence microscopy with Hochest staining, and the cell apoptosis rate was measured with flow cytometry. The expression level of PLTP and caspase-3 activity in the cells were examined with Western blotting.

RESULTSExposure to CSE significantly increased the cell apoptosis rate from (1.68∓0.098)% to (18.663∓0.964)% (P<0.001). Hoechst staining revealed distinct apoptotic changes in CSE-treated cells, which showed increased PLTP expression and caspase-3 activity. PLTP knockdown with the specific siRNA partly suppressed the SCE-induced enhancement of caspase-3 activity in the cells.

CONCLUSIONPLTP may play a role in CSE-induced apoptosis of rat alveolar cells in vitro.

Animals ; Apoptosis ; Caspase 3 ; metabolism ; Cell Line ; Epithelial Cells ; cytology ; Phospholipid Transfer Proteins ; metabolism ; RNA, Small Interfering ; Rats ; Smoke ; adverse effects ; Tobacco ; adverse effects

OBJECTIVETo investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism.

METHODSHepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR.

RESULTSExposure to TSA caused significant dose- and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)% and (18.14 ± 0.42)% after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes.

CONCLUSIONSTSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.

Acetylation ; Apoptosis ; Cell Cycle Checkpoints ; Cell Proliferation ; drug effects ; Cyclin D1 ; metabolism ; Hep G2 Cells ; drug effects ; Histone Deacetylase 1 ; metabolism ; Histone Deacetylases ; metabolism ; Histones ; metabolism ; Humans ; Hydroxamic Acids ; pharmacology ; Wnt Signaling Pathway ; bcl-2-Associated X Protein ; metabolism ; beta Catenin ; metabolism