Sophocarpine attenuates liver fibrosis by inhibiting the TLR4 signaling pathway in rats.

AIM: To explore the effect of sophocarpine on experimental liver fibrosis and the potential mechanism involved. METHODS: Sophocarpine was injected intraperitoneally in two distinct rat hepatic fibrosis models induced either by dimethylnitrosamine or bile duct ligation. Masson's trichrome staining, Sirius red staining and hepatic hydroxyproline level were used for collagen determination. Primary hepatic stellate cells (HSCs) were isolated and treated with different concentrations of sophocarpine. Real-time reverse transcription-polymerase chain reaction was used to detect the mRNA levels of fibrotic markers and cytokines. The expression of pathway proteins was measured by Western blot. The Cell Counting Kit-8 test was used to detect the proliferation rate of activated HSCs treated with a gradient concentration of sophocarpine. RESULTS: Sophocarpine decreased serum levels of aminotransferases and total bilirubin in rats under chronic insult. Moreover, administration of sophocarpine suppressed extracellular matrix deposition and prevented the development of hepatic fibrosis. Furthermore, sophocarpine inhibited the expression of α-smooth muscle actin (SMA), interleukin (IL)-6, transforming growth factor-ß1 (TGF-ß1), Toll-like receptor 4 (TLR4), and extracellular-related kinase (ERK) in rats. Sophocarpine also down-regulated the mRNA expression of α-SMA, collagen I, collagen III, TGF-ß1, IL-6, tumor necrosis factor-α and monocyte chemoattractant protein-1, and decreased protein levels of TLR4, p-ERK, p-JNK, p-P38 and p-IKK in vitro after Lipopolysaccharide induction. In addition, sophocarpine inhibited the proliferation of HSCs accompanied by a decrease in the expression of Cyclin D1. The protein level of proliferating cell nuclear antigen was decreased in activated HSCs following a gradient concentration of sophocarpine. CONCLUSION: Sophocarpine can alleviate liver fibrosis mainly by inhibiting the TLR4 pathway. Sophocarpine may be a potential chemotherapeutic agent for chronic liver diseases.

[Andrographolide inhibits extracellular signal-regulated kinase 1/2 signaling pathway in activated macrophages].

OBJECTIVE: To investigate the effects of andrographolide on extracellular signal-regulated kinase 1/2 (ERK1/2) signaling pathway and tumor necrosis factor-α (TNF-α) expression in lipopolysaccharide (LPS)-activated macrophages. METHODS: LPS-activated mouse peritoneal macrophages were cultured in media with different concentrations of andrographolide. Cytotoxicity of andrographolide was detected by cell counting kit-8. The macrophages were lysed, and then expressions of phosphorylated ERK1/2, JNK and p38 and nuclear factor-κB inhibitor (IκBα) protein were detected by Western blotting and TNF-α mRNA expression was detected by reverse transcription-polymerase chain reaction. Supernatants of the macrophages were used to detect content of TNF-α protein by enzyme-linked immunosorbent assay. RESULTS: Andrographolide at 1-100 µg/mL showed no cytotoxicity on LPS-activated mouse peritoneal macrophages. Andrographolide inhibited ERK1/2 phosphorylation in LPS-activated murine peritoneal macrophages, which was concentration-dependent (P<0.01). Andrographolide at 1-25 µg/mL had no effects on phosphorylation levels of JNK and p38 and IκBα degradation in LPS-stimulated mouse peritoneal macrophages. In activated macrophages, TNF-α expression was inhibited by 12 µg/mL andrographolide and 20 µmol/L PD98059 (inhibitor of ERK1/2 signaling pathway) at both mRNA expression and protein secretion levels. CONCLUSION: In LPS-activated macrophages, andrographolide may inhibit the expression of TNF-α by inhibiting ERK1/2 signaling pathway.

Sophocarpine alleviates non-alcoholic steatohepatitis in rats.

BACKGROUND AND AIM: Non-alcoholic steatohepatitis (NASH) is one entity in the spectrum of non-alcoholic fatty liver disease (NAFLD). The aim of this study was to explore the prevention and therapeutic effect of sophocarpine on experimental rat NASH. METHODS: Sophocarpine with the dosage of 20 mg/kg/day was injected into NASH rats. At the end of 12 weeks, all rats were killed to detect the degree of fatty degeneration, inflammation and fibrosis. RESULTS: Sophocarpine intervention (in the pro-treated and treated groups) resulted in a significant decrease of liver weight, liver index, serum transaminase and serum lipids. Messenger RNA expressions of leptin, interleukin (IL)-6, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-ß1, procollagen-I and α-smooth muscle actin (SMA) and deposition of IL-6, TNF-α and TGF-ß1 in liver decreased, whereas the messenger RNA expression of adiponectin increased significantly compared with that in the model group. Moreover, histological improvement was also observed in the sophocarpine intervention group. In addition, there was no significant difference in any detected indicator between the pro-treated and treated group. CONCLUSIONS: Sophocarpine could decrease the level of serum transaminase, improve lipid metabolism, reduce synthesis of inflammatory cytokines TNF-α, TGF-ß1 and IL-6, activate protective adipocytokine adiponectin, and might be selected as a promising agent for the clinical prevention and therapy of NASH.