[Angiotensin (1-7) inhibits angiotensin II-stimulated expression of connective tissue growth factor mRNA in hepatic stellate cells].

To explore the angiotensin peptide [Ang (1-7)]-mediated inhibition of Ang II in human hepatic stellate cells (HSCs) and determine the involvement of the ACE2-Ang (1-7)-Mas axis. The human HSC line, LX2, was used in all experiments, and divided into control (unstimulated) and Ang II-stimulated (10-6 mol/L) groups. The Ang II-stimulated cells were further divided among several pre-treatment (prior to Ang II) groups: ROCK-inhibited (Y27632 blocking agent, 10-6 mol/L); irbesartan-inhibited (AT-1 receptor antagonist, 10-6 mol/L); and Mas receptor-inhibited (A779 Mas receptor antagonist, 10-6 mol/L).

Upregulation of angiotensin-converting enzyme (ACE) 2 in hepatic fibrosis by ACE inhibitors.

1. The role of angiotensin-converting enzyme (ACE) 2 is likely to balance the status of the renin-angiotensin system (RAS) by degrading angiotensin (Ang) II and generating Ang-(1-7). Earlier demonstrations that ACE2 is insensitive to ACE inhibitors prompted us to evaluate the effect of ACE inhibitors on ACE2 expression.

[Effect of angiotensin1-7 on alpha-smooth muscle actin protein expression in rat hepatic stellate cells].

Objective: To investigate the effect of angiotensin II and angiotensin1-7 on alpha-smooth muscle actin (alpha-SMA)-induced Ca(2+)-independent pathways mediated by Rho kinase2 in hepatic stellate cells (HSCs).

Methods: HSC-T6 cells were treated with 10 micromol/L of AngII, Ang1-7, AngII +Ang1-7, and Ang1-7+A779. RT-PCR was used to detect the expression of Rho kinase2 (Rock2) in Ca(2+)-independent pathways, and alpha-SMA protein expression was detected by Western blotting.

[Role of Rho-Rock pathways induced by angiotensin II in hepatic stellate cell contraction].

Objective: To investigate the mechanism of Ca(2+)-independent pathways mediated by Rho-kinase in contraction of hepatic stellate cells (HSCs) induced by angiotonin II (Ang II).

Methods: Human HSCs of the line HSC-T6 were cultured and randomly divided into 6 groups: negative control group, Ang II group treated by Ang II10 micromol/L for 15 min, Ang II + irbesartan (Ang II receptor inhibitor) group, exposed to irbesartan for 60 min prior to Ang II treatment, Ang II + Y27632 (Rho kinase specific inhibitor) exposed to Y27632 for 60 min prior to Ang II treatment, Ang II + ML-7 (myosin light chain kinase specific inhibitor) + saturo (protein kinase C specific inhibitor) group exposed to stauro for 60 min prior to Ang II treatment, and Ang II + Y27632 + ML-7 + stauro group, exposed to Y27632 and stauro for 60 min prior to Ang II treatment. The cell contraction was detected by silicone-rubber-membrane cultivation directly.

[Effect of angiotensin II on Rho-Rock pathway in rat hepatic stellate cell contraction].

Objective: To investigate the mechanisms of angiotonin II (AngII)-induced Ca(2+)-independent pathways mediated by Rho kinase in hepatic stellate cells (HSCs).

Methods: HSC-T6 cells were treated with 1 micromol/L of AngII, and the subsequent cell contraction was directly observed with silicone rubber membrane culture method. The cells with 10 micromol/L AngII treatment were examined for myosin light chain (MLC) phosphorylation level using Western blotting, and the effects of irbesartan (a specific inhibitor of AngII 1- receptor) and Y27632 (a Rho kinase inhibitor) on AngII-induced MLC phosphorylation were evaluated.

[Angiotensin II stimulates platelet-derived growth factor-B expression in hepatic stellate cells by activating EGR-1].

Objective: To investigate the signal transduction mechanism underlying the effects of angiotensin II (AngII) on extracellular signal-regulated kinase 1/2 (ERK1/2), early growth response-1 (EGR-1) and platelet-derived growth factor-B (PDGF-B) in hepatic stellate cells (HSCs).

Methods: HSC-T6 cells treated with AngII for 10 or 30 min were examined for phospho-P42/44 protein expression using Western blotting. In another experiment, the cells were preincubated for 1 h in the presence of U0126 (an inhibitor of the MAPK/ERK kinase), irbesartan (an AT-1 receptor blocker), or antioxidant-N-acetylcysteine (NAC) prior to AngII exposure, and the protein expression of phospho-P42/44 and PDGF-B were measured with Western blotting.

[A preliminary investigation of nuclear factor kappa B in peripheral blood lymphocytes of patients with hepatitis B].

Objective: To explore the activity of nuclear factor kappa B (NF-kappaB) in peripheral blood lymphocytes (PBL) of patients with hepatitis B.

Methods: The PBL of patients with different types of hepatitis B and healthy individuals were isolated and then the nuclear extract was prepared. Assessment of NF-kappaB DNA binding activity was performed by electrophoretic mobility shift assay (EMSA) using digoxin labeled double-stranded oligonucleotide containing kappa B consensus sequence.