AIM: To evaluate the possible role of Tribble 3 (TRB3) in a rat model of non-alcoholic fatty liver disease (NAFLD) and its signal transduction mechanism.METHODS: Thirty Sprague-Dawley rats were randomized into t...AIM: To evaluate the possible role of Tribble 3 (TRB3) in a rat model of non-alcoholic fatty liver disease (NAFLD) and its signal transduction mechanism.METHODS: Thirty Sprague-Dawley rats were randomized into three groups: normal control group, non-alcoholic fatty liver group A (fed on a high-fat diet for 8 wk) and group B (fed on a high-fat diet for 16 wk). To determine the degree of hepatic steatosis in rats of each group, livers were stained with hematoxylin and eosin, and evaluated; real-time fluorescent quantitative reverse transcriptase-polymerase chain reaction was performed to measure the expression levels of TRI33 mRNA, and Western blotting analysis was done to determine the expression levels of protein kinase B (Akt) and phosphorylated protein kinase B (p-Akt-Thr308, p-Akt-Ser473).RESULTS: Hepatic steatosis was evident in both NAFLD groups: mild to moderate hepatic steatosis occurred in group A, mainly as mild steatosis.Moderate to severe hepatic steatosis occurred in group B, mainly as severe steatosis. The expression level of TRB3 mRNA in group B was significantly higher than in the control group (122.28 ± 95.37 vs 3.06 ± 2.33,P = 0.002) and group A (122.28 ± 95.37 vs 5.77 ± 4.20,P = 0.001). There was no significant difference in the expression levels of Akt (1.03 ± 0.53 vs 1.12 ± 0.77,P = 0.729) and p-Akt-Thr308 (0.82 ± 0.45 vs 0.92 ± 0.38, P = 0.592) between group A and the control group. The expression level of Akt and p-Akt-Thr308 in group B was significantly lower than in group A (Akt 0.41 ± 0.16 vs 1.12 ± 0.77, P = 0.008; p-Akt-Thr308 0.47 ± 0.19 vs 0.82 ± 0.45, P = 0.036) and the control group (Akt 0.41 ± 0.16 vs 1.03 ± 0.53, P = 0.018;p-Akt-Thr308 0.47 ± 0.19 vs 0.92 ± 0.38, P = 0.010).The expression level of p-Akt-Ser473 in group A was significantly higher than in group B (1.48 ± 0.50 vs 0.81± 0.39, P = 0.041) as well as the control group (1.48 ± 0.50 vs 0.45 ± 0.26, P = 0.003).CONCLUSION: TRB3 blocks insulin signaling by inhibiting Akt activation, which contributes to insulin resistance. It may be an important factor in the occurrence and development of NAFLD.展开更多
Objective:The aim of the research was to study the effects of prolactin-inducible protein(PIP) downregulation on metastatic abilities of human breast cancer MDA-MB-453 cells.Methods:PIP-siRNA was transfected into huma...Objective:The aim of the research was to study the effects of prolactin-inducible protein(PIP) downregulation on metastatic abilities of human breast cancer MDA-MB-453 cells.Methods:PIP-siRNA was transfected into human breast cancer MDA-MB-453 cells through liposome.Reverse transcription PCR and immunocytochemistry were employed to detect the downregulated expression of PIP.Cell migration,adhesion and invasion assays were performed to assess the impacts of PIP downregulation on cell migration,adhesion and invasion respectively.Results:Knockdown of PIP obviously inhibited cell migration,the migrated cells were decreased by 83.1% compared with the negative control group.Cell adhesion was also reduced,the adhesion rates at 30 min and 60 min were decreased by 42.6% and 48.5% respectively compared with the negative control group.Moreover,PIP downregulation resulted in decreased invasion rate by 73.9%.Conclusion:Reduced PIP expression in MDA-MB-453 cells can inhibit the abilities of migration,adhesion and invasion,which suggests that PIP plays an important role in the metastatic potency of breast cancer cells.展开更多
文摘AIM: To evaluate the possible role of Tribble 3 (TRB3) in a rat model of non-alcoholic fatty liver disease (NAFLD) and its signal transduction mechanism.METHODS: Thirty Sprague-Dawley rats were randomized into three groups: normal control group, non-alcoholic fatty liver group A (fed on a high-fat diet for 8 wk) and group B (fed on a high-fat diet for 16 wk). To determine the degree of hepatic steatosis in rats of each group, livers were stained with hematoxylin and eosin, and evaluated; real-time fluorescent quantitative reverse transcriptase-polymerase chain reaction was performed to measure the expression levels of TRI33 mRNA, and Western blotting analysis was done to determine the expression levels of protein kinase B (Akt) and phosphorylated protein kinase B (p-Akt-Thr308, p-Akt-Ser473).RESULTS: Hepatic steatosis was evident in both NAFLD groups: mild to moderate hepatic steatosis occurred in group A, mainly as mild steatosis.Moderate to severe hepatic steatosis occurred in group B, mainly as severe steatosis. The expression level of TRB3 mRNA in group B was significantly higher than in the control group (122.28 ± 95.37 vs 3.06 ± 2.33,P = 0.002) and group A (122.28 ± 95.37 vs 5.77 ± 4.20,P = 0.001). There was no significant difference in the expression levels of Akt (1.03 ± 0.53 vs 1.12 ± 0.77,P = 0.729) and p-Akt-Thr308 (0.82 ± 0.45 vs 0.92 ± 0.38, P = 0.592) between group A and the control group. The expression level of Akt and p-Akt-Thr308 in group B was significantly lower than in group A (Akt 0.41 ± 0.16 vs 1.12 ± 0.77, P = 0.008; p-Akt-Thr308 0.47 ± 0.19 vs 0.82 ± 0.45, P = 0.036) and the control group (Akt 0.41 ± 0.16 vs 1.03 ± 0.53, P = 0.018;p-Akt-Thr308 0.47 ± 0.19 vs 0.92 ± 0.38, P = 0.010).The expression level of p-Akt-Ser473 in group A was significantly higher than in group B (1.48 ± 0.50 vs 0.81± 0.39, P = 0.041) as well as the control group (1.48 ± 0.50 vs 0.45 ± 0.26, P = 0.003).CONCLUSION: TRB3 blocks insulin signaling by inhibiting Akt activation, which contributes to insulin resistance. It may be an important factor in the occurrence and development of NAFLD.
文摘Objective:The aim of the research was to study the effects of prolactin-inducible protein(PIP) downregulation on metastatic abilities of human breast cancer MDA-MB-453 cells.Methods:PIP-siRNA was transfected into human breast cancer MDA-MB-453 cells through liposome.Reverse transcription PCR and immunocytochemistry were employed to detect the downregulated expression of PIP.Cell migration,adhesion and invasion assays were performed to assess the impacts of PIP downregulation on cell migration,adhesion and invasion respectively.Results:Knockdown of PIP obviously inhibited cell migration,the migrated cells were decreased by 83.1% compared with the negative control group.Cell adhesion was also reduced,the adhesion rates at 30 min and 60 min were decreased by 42.6% and 48.5% respectively compared with the negative control group.Moreover,PIP downregulation resulted in decreased invasion rate by 73.9%.Conclusion:Reduced PIP expression in MDA-MB-453 cells can inhibit the abilities of migration,adhesion and invasion,which suggests that PIP plays an important role in the metastatic potency of breast cancer cells.