[Effect of regulating TGF-ß1/Smad signaling pathway on apoptosis of hepatocellular carcinoma HepG2 cells under endoplasmic reticulum stress].

Objective: To investigate the effect of TGF-ß1/Smad signaling pathway on the apoptosis of HepG2 cells under endoplasmic reticulum stress (ERS). Methods: An ERS model was established firstly. Human hepatocellular carcinoma HepG2 cells were treated with 3 µmol/L tunicamycin (TM) for 24 h to induce ERS. Cells were divided into 6 groups, each with 3 replicate holes, and the experiment was repeated 3 times. The 6 groups included untreated group, TM group (3 µmol/L TM treatment group), TM + NC group(3 µmol/L TM + si-TGF-ß1 negative control group), TM + si-TGF-ß1 group(3 µmol/L TM + si-TGF-ß1 group), TM + pEX-3 group(3 µmol/L TM + plasmid control group), and TM + TGF-ß1 pEX-3 group(3 µmol/L TM + TGF-ß1 overexpressed plasmid group). HepG2 cells were transfected with TGF-ß1 small interfering RNA (TGF-ß1 si-RNA) and TGF-ß1 overexpressed plasmids (TGF-ß1 pEX-3) by Lipofectamine. Twenty-four hours after transfection, RT-qPCR and Western blot were used to detect the expression of TGF-ß1 and p-Smad2 in HepG2 cells of each group. CCK-8 and flow cytometry were used to analyze changes in the proliferation inhibition rate and apoptosis rate of HepG2 cells in each group. Results: Compared with the untreated group, the expressions of TGF-ß1 and p-Smad2 in TM group were significantly reduced (P＜0.05). Compared with the TM group, the expressions of TGF-ß1 and p-Smad2, as well as the cell proliferation inhibition rate and apoptosis rate in TM + si-TGF-ß1 group were obviously decreased (P＜ 0.01), while the expressions of TGF-ß1 and p-Smad2, cell proliferation inhibition rate and apoptosis rate of TM + TGF-ß1 pEX-3 group were significantly increased (P＜0.01). Conclusion: The TGF-ß1/Smad signaling pathway was inhibited in hepatocellular carcinoma HepG2 cells under ERS, when this pathway was activated, the apoptosis rate of HepG2 cells under ERS was increased significantly.

[Effects of astragaloside-IV on the expression of inflammatory factor and proliferation of glomerular mesangial cells induced by angiotensin â ¡].

OBJECTIVE: To study the effects of astragaloside-IV (As-IV) on the expression of inflammatory factor and proliferation of glomerular mesangial cells (GMCs) induced by angiotensin Ⅱ(AngⅡ). METHODS: The in vitro model of diabetic nephropathy(DN) was mimic by angiotensin Ⅱ (10-6mol/L)inducing GMCs injury. Then the GMCs were treated with As-IV at different concentrations(25,50,100 µmol/L)for 48 hours. The proliferation of GMCs was detected by MTT. The level of reactive oxidative species (ROS) was measured by flow cytometry. The expression of monocyte chemoattractant protein-1(MCP-1) protein in supernatant was detected by enzyme- linked immunosorbent assay (ELISA). The expression of transforming growth factor-ß1(TGF-ß1) in GMCs was measured by Western blot. RESULTS: Compared with model group, the proliferation of GMCs was inhibited in As-IV group. As-IV decreased the level of intercellular ROS, down-regulated the secretion of MCP-1 and the expression of TGF-ß1 proteins. CONCLUSIONS: As-IV could inhibit cell proliferation and inflammatory factors expression on GMCs induced by AngⅡ.