Objective Using an adenoviral vector , the wild-type PTEN gene was transduced into activated hepatic stellate cell (HSC) in vitro and the phosphorylation status of Akt were investigated. Methods The wild type PTEN gene was transduced into activated HSC in vitro mediated by adenoviral vector. The expressions of PTEN and total Akt in HSC were measured by Western blot and Real-time fluorescent quantitation PCR. And the expressions of phosphorylated Akt (Thr308) in HSC was determined by Western blot. Results The data showed that exogenous wild type PTEN gene was successfully transduced and expressed in activated HSC in vitro. The over-expression of wild type PTEN resulted in the significant down-regulated expression of phosphorylated Akt (Thr308) in activated HSC (P < 0.01). But no significant defferences were found in the expression of total Akt in activated HSC at both transcriptional and translational levels(P>0.50). Conclusions The overexpression of wild-type PTEN can negatively regulate PI3K/Akt signaling transduction by inhibiting the phosphorylation of Akt in activated HSC in vitro.

Objective:To investigate the dynamic expression of protein tyrosine phosphatase SHP2 in liver tissue of rats with carbon tetrachloride (CCl 4)-induced liver fibrosis. Methods:Rat liver fibrosis model was established by intraperitoneal injection of CCl 4. Rat liver tissue histopathological changes were detected by HE and Masson-trichrome staining. Immunohistochemical staining, Western blot and real-time fluorescent quantitative PCR were used to detect SHP2 protein and mRNA expression in rat liver tissue. One-way analysis of variance was used for the comparison of means between multiple groups, and the LSD test was used for further inter-group comparison. Results:CCl 4-induced rat liver fibrosis model was successfully constructed, and with the extension of modeling time, the degree of liver fibrosis in rats were aggravated gradually. Immunohistochemical staining results showed that SHP2 was mainly expressed in the cytoplasm of rat liver tissues. With the aggravation of liver fibrosis, the number of cells with positive expression of SHP2 was aggravated gradually ( P < 0.05). Western blot and real-time fluorescent quantitative PCR results showed that the expressions of SHP2 protein and mRNA in rat fibrotic liver tissues at different times in week 2, 4, 6, and 8 were higher in modeling than control group ( P < 0.05), and was aggravated gradually with the liver fibrosis aggravation ( P < 0.05). Conclusion:The expression of SHP2 protein and mRNA in the liver tissue of rats with CCl 4-induced liver fibrosis increased gradually with the degree of liver fibrosis, and the degree of increase was consistent with the degree of liver fibrosis.

Objective:To investigate the effect of adenovirus-mediated short hairpin RNA (shRNA) downregulating SH2 domain-containing protein tyrosine phosphatase 2 (SHP2) on the apoptosis of human hepatic stellate cells LX-2 cultured in vitro.Methods:The recombinant adenovirus Ad-shRNA/SHP2 carrying shRNA targeted SHP2 and expressing green fluorescent protein (GFP), and the empty control virus Ad-GFP expressing GFP were transfected into LX-2 cells cultured in vitro. Real-time fluorescence quantitative PCR was used to detect SHP2 mRNA expression in LX-2 cells. Western blot was used to detect the protein expressions of SHP2, Bax, and Bcl-2 in LX-2 cells. TUNEL and annexin-V/propidium iodide dual-labeled flow cytometry were used to detect apoptosis in LX-2 cells. Experimental group: (1) Control group: LX-2 cells were transfected with DMEM instead of adenovirus; (2) Ad-GFP group: transfected with empty virus Ad-GFP; (3) Ad-shRNA/SHP2 group: transfected with recombinant adenovirus Ad-shRNA/SHP2. The means between multiple groups were compared using a one-way ANOVA and the LSD test was used for inter group comparisons.Results:shRNA-targeted SHP2 significantly down-regulated the expression of SHP2 protein and mRNA in LX-2 cells ( P < 0.05). The TUNEL and annexin-V/propidium iodide dual-labeled flow cytometry results showed that the apoptosis rate of LX-2 cells in the Ad-shRNA/SHP2 group (12.755%±1.606%, 19.340%±2.505%) ( P < 0.05) was significantly higher compared to the control group (3.077%±0.731%, 9.438%±0.804%) and the Ad-GFP group (3.250%±0.851%, 8.893%±1.982%), with no statistically significant difference between the control group and the Ad-GFP group ( P > 0.05). Western blot analysis of Bax and Bcl-2 protein expression in LX-2 cells of each group revealed that the Bax protein expression was significantly higher in the Ad shRNA/SHP2 group (2.493 ± 0.203) ( P < 0.05) compared to the control group and Ad-GFP group (1.989 ± 0.147, 1.999 ± 0.162), with no statistically significant difference between the control group and the Ad-GFP group ( P > 0.05), while the Bcl-2 protein was significantly decreased in the Ad-shRNA/SHP2 group (1.042±0.148) compared with the control group and the Ad-GFP group (1.707±0.146, 1.521±0.142), with no statistically significant difference between the control group and the Ad-GFP group ( P > 0.05). Conclusions:SHP2 expression down-regulation induces apoptosis of human hepatic stellate cells LX-2 in vitro by reducing Bcl-2/Bax.