Quanfang Huang

Protective effect of tormentic acid from Potentilla chinensis against lipopolysaccharide/d-galactosamine induced fulminant hepatic failure in mice

A compound was isolated from Potentilla chinensis, and it was identified as tormentic acid (TA) based on its physicochemical properties and spectral data. The hepatoprotective effect of TA was evaluated using an acute liver failure model induced by lipopolysaccharide (LPS)/D-galactosamine (D-GalN). The results revealed that TA significantly prevented LPS/D-GalN-induced fulminant hepatic failure, as evidenced by the decrease in serum aminotransferase and total bilirubin activities and the attenuation of histopathological changes. TA alleviated the pro-inflammatory cytokines including TNF-α and NO/iNOS by inhibiting nuclear factor-κB (NF-κB) activity. Moreover, TA strongly inhibited lipid peroxidation, recruited the anti-oxidative defense system, and increased HO-1 activity. In addition, TA significantly attenuated increases in TUNEL-positive hepatocytes through decreasing the levels of cytochrome c, as well as caspases-3, 8 and 9, while augmenting the expression of Bcl-2. In conclusion, TA protects hepatocytes against LPS/D-GalN-induced injury by blocking NF-κB signaling pathway for anti-inflammatory response and attenuating hepatocellular apoptosis. Consequently, TA is a potential agent for preventing acute liver injury and may be a major bioactive ingredient of Potentilla chinensis.

Protective effect of genistein isolated from Hydrocotyle sibthorpioides on hepatic injury and fibrosis induced by chronic alcohol in rats.

This study examined the effect of genistein isolated from Hydrocotyle sibthorpioides on chronic alcohol-induced hepatic injury and fibrosis. Rats underwent intragastric administration of alcohol (5.0-9.5g/kg) once a day for 24 weeks. A subset of rats were also intragastrically treated with genistein (0.5, 1 or 2mg/kg) once a day. Genistein significantly decreased the plasma alcohol concentration, inhibited the activities of alanine and aspartate aminotransferases and decreased levels of inflammatory mediators, including interleukin 6, tumor necrosis factor-α and myeloperoxidase, via down-regulation of nuclear factor-κB. Moreover, genistein effectively inhibited collagen deposition and reduced pathological tissue damage as determined by hepatic fibrosis biomarkers, such as total hyaluronic acid, laminin, and type III collagen. Mechanistically, studies showed that genistein markedly reduced lipid peroxidation, recruited the anti-oxidative defense system, inhibited CYP2El activity, promoted extracellular matrix degradation by modulating the levels of tissue inhibitor of matrix metalloproteinase-1 and matrix metalloproteinase-2, induced HSC apoptosis by down-regulating B-cell lymphoma 2 mRNA, and inhibited the expression of α-smooth muscle actin and transforming growth factor β(1) proteins. In conclusion, genistein exerts a preventative effect to ameliorate developing liver injury and even liver fibrosis induced by chronic alcohol administration in rats.

Protective effect of Fufang-Liu-Yue-Qing, a traditional Chinese herbal formula, on CCl4 induced liver fibrosis in rats

ETHNOPHARMACOLOGICAL RELEVANCE Chinese prescription Fufang-Liu-Yue-Qing (FLYQ) has long been employed clinically to treat chronic hepatitis B, and we have reported its beneficial effects on liver fibrosis in vitro. The present study was investigated to verify protective effects of FLYQ on liver fibrosis in a rat model and to investigate the underlying mechanisms which have not been explored yet. MATERIALS AND METHODS Liver fibrosis was established by intragastric administration of 2 ml/kg CCl(4) twice a week for 12 weeks. During the experiment, the model group received CCl(4) only, and the normal control group received an equal volume of saline. Treatment groups received not only CCl(4) for 12 weeks, but also the corresponding drugs, colchicine (1.00 mg/kg/day) or FLYQ (300, 150, 75 mg/kg/day) from 5 to 12 weeks. RESULTS Analysis experiments showed that FLYQ could significantly alleviate liver injury, as indicated by decreasing levels of ALT, AST, ALP, GGT, IL-6 and TNF-α. Moreover, FLYQ could effectively inhibit collagen deposition and reduce the pathological tissue damage. Research on mechanism showed that FLYQ was able to markedly reduce lipid peroxidation, recruit the anti-oxidative defense system, promote ECM degradation by modulating the levels of TIMP-1 and MMP-2, and induce HSC apoptosis by down-regulating bcl-2 mRNA, as well as inhibit the expressions of α-SMA and TGF-β(1) proteins. CONCLUSIONS Our results show that FLYQ is effective in attenuating hepatic injury and fibrosis in the CCl(4)-induced rat model, which should be developed as a new drug for treatment of liver fibrosis and even cirrhosis.

Protective effect of madecassoside against cognitive impairment induced by d-galactose in mice

This study was designed to investigate the protective effect of madecassoside from Hydrocotyle sibthorpioides against cognitive impairment induced by D-galactose (D-gal) in mice. The result revealed that treatment with madecassoside significantly reversed D-gal-induced learning and memory impairments, as measured by the Morris water-maze test. Studies on the potential mechanisms of this action showed that madecassoside significantly reduced oxidative stress and suppress inflammatory responses via blocking NF-κB and ERK/p38 MAPK pathways. Moreover, madecassoside markedly attenuated the content and deposition of β-amyloid peptide by inducing a decrease in the expression of amyloid protein precursor, β-site amyloid cleaving enzyme-1 and cathepsin B and an increase in the levels of neprilysin and insulin-degrading enzyme. Madecassoside significantly increased the expression of synapse plasticity-related proteins in the hippocampus, such as postsynaptic density 95, long-term potentiation, N-methyl-D-aspartic acid receptors, Ca(2+)/calmodulin-dependent protein kinase II, NMDA receptor subunit 1, protein kinase C, protein kinase A, cAMP-response element binding protein, and brain-derived neurotrophic factor. In addition, madecassoside significantly increased the levels of acetylcholine but decreased cholinesterase activity. In conclusion, the protective effect of madecassoside against d-gal-induced cognitive impairment was mainly due to its ability to reduce oxidative damage, improve synaptic plasticity and restore cholinergic function. These findings suggest that madecassoside can be considered as a potential agent for preventing cognitive impairment.

Isoorientin from Gypsophila elegans induces apoptosis in liver cancer cells via mitochondrial-mediated pathway.

ETHNOPHARMACOLOGICAL RELEVANCE Gypsophila elegans has been used as a traditional herbal medicine for treating immune disorders and chronic liver diseases in China. The aim of this study is to isolate an active ingredient from this herb and investigate its anti-tumor activity. MATERIALS AND METHODS An active ingredient was isolated from the ethanol extract using bioassay-guided screening. And its anti-tumor activity was analyzed by testing the cytotoxicity, lactate dehydrogenase (LDH) release, clonogenecity and migration in HepG2 cells. To investigate its potential mechanism, cell apoptosis, cell cycle arrest, reactive oxygen species (ROS), cytochrome c, mitochondria membrane potential (MMP) and caspase level were determined in liver cancer cell line HepG2. RESULTS A flavonoid glycoside, i.e., G. elegans isoorientin (GEI), was isolated from this herb and identified as Isoorientin-2″-O-α-l-arabinopyranosyl. Our results showed that GEI significantly inhibited the viability and proliferation of HepG2 cells in a dose- and time-dependent manner, and its cytotoxic effect was also confirmed by the elevated level of LDH. GEI treatment could markedly inhibit the clonogenicity and migration of HepG2 cells. Moreover, GEI induced remarkable apoptotic death of HepG2 cells through cell cycle arrest at G1 phase via the regulation of cell cycle-related genes, such as cyclin D, cyclin E and CDK2. Further study showed that GEI treatment significantly elevated ROS formation, followed by attenuation of MMP via up-regulation of Bax and down-regulation of Bcl-2, accompanied by cytochrome c release to the cytosol. In addition, GEI treatment resulted in a significant dose-dependent increase in caspase-3 and -9 proteolytic activities. CONCLUSION The present study demonstrates that the ability of GEI to induce apoptosis against HepG2 cells mediated by mitochondrial-mediated pathway.

Effect and mechanism of methyl helicterate isolated from Helicteres angustifolia (Sterculiaceae) on hepatic fibrosis induced by carbon tetrachloride in rats

ETHNOPHARMACOLOGICAL RELEVANCE Methyl helicterate is a triterpenoid isolated from Helicteres angustifolia (Sterculiaceae), one of the valuable traditional Chinese herbs. Antifibrotic activities of H. angustifolia have been extensively proved. AIM OF THE STUDY The purpose of this study was to investigate the effect of methyl helicterate (MH) on liver fibrosis in rats induced by carbon tetrachloride (CCl(4)) and to explore its underlying mechanism. MATERIALS AND METHODS Hepatic fibrosis was induced in male Sprague-Dawley (SD) rats by intragastric administration with 2 ml/kg CCl(4) (mixed 1:1 in peanut oil) twice a week for 12 weeks. To evaluate the effect of MH (16.72, 33.45, 66.90 mg/kg) on hepatic fibrosis, liver function, histological study and hepatic fibrosis evaluation were performed. Liver function was assessed by determining the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin (Alb) and total protein (TP). The biomarkers such as hydroxyproline (Hyp), hyaluronic acid (HA), type III precollagen (PCIII) and laminin (LN) were examined for the evaluation of hepatic fibrosis. The underlying mechanism was investigated by measuring oxidative stress level and detecting the expression of TGF-β1 mRNA and Smad3 protein. RESULTS MH (33.45, 66.90 mg/kg) treatment significantly inhibited the loss of body weight and the increase of liver index in rats induced by CCl(4). MH also improved the liver function as indicated by decreasing serum enzymatic activities of ALT, AST, TP and Alb (P<0.05). Histological results indicated that MH alleviated liver damage and reduced the formation of fibrous septa. Moreover, MH significantly decreased liver Hyp, HA, LN and PCIII (P<0.05). Research on mechanism showed that MH could markedly reduce liver malondialdehyde (MDA) concentration, increase activities of liver superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and inhibit the expression of TGF-β1 mRNA and Smad3 protein (P<0.05). CONCLUSIONS Our findings indicated that MH can inhibit CCl(4)-induced hepatic fibrosis, which may be ascribed to its radical scavenging action, antioxidant activity, and modulation of TGF-β-Smad3 signaling pathway.

Didymin Alleviates Hepatic Fibrosis Through Inhibiting ERK and PI3K/Akt Pathways via Regulation of Raf Kinase Inhibitor Protein

Background: Didymin has been reported to have anti-cancer potential. However, the effect of didymin on liver fibrosis remains illdefined. Methods: Hepatic fibrosis was induced by CCl4 in rats. The effects of didymin on liver pathology and collagen accumulation were observed by hematoxylin-eosin and Massons trichrome staining, respectively. Serum transaminases activities and collagen-related indicators levels were determined by commercially available kits. Moreover, the effects of didymin on hepatic stellate cell apoptosis and cell cycle were analyzed by flow cytometry. Mitochondrial membrane potential was detected by using rhodamine-123 dye. The expression of Raf kinase inhibitor protein (RKIP) and the phosphorylation of the ERK/MAPK and PI3K/Akt pathways were assessed by Western blot. Results: Didymin significantly ameliorated chronic liver injury and collagen deposition. It strongly inhibited hepatic stellate cells proliferation, induced apoptosis and caused cell cycle arrest in G2/M phase. Moreover, didymin notably attenuated mitochondrial membrane potential, accompanied by release of cytochrome C. Didymin significantly inhibited the ERK/MAPK and PI3K/Akt pathways. The effects of didymin on the collagen accumulation in rats and on the biological behaviors of hepatic stellate cells were largely abolished by the specific RKIP inhibitor locostatin. Conclusion: Didymin alleviates hepatic fibrosis by inhibiting ERK/MAPK and PI3K/Akt pathways via regulation of RKIP expression.

Gypsophila elegans isoorientin attenuates CCl4-induced hepatic fibrosis in rats via modulation of NF-κB and TGF-β1/Smad signaling pathways

The hepatoprotective effect of Gypsophila elegans isoorientin (GEI) was evaluated using a hepatic fibrosis model induced by CCl4 in rats. The results revealed that GEI significantly prevented CCl4-induced liver injury and fibrosis, as evidenced by the attenuation of histopathological changes, the decrease in serum aminotransferase, and the inhibition of collagen accumulation. GEI strongly inhibited lipid peroxidation and recruited anti-oxidative defense system. Moreover, GEI alleviated pro-inflammatory cytokines such as TNF-α, IL-1β and IL-6 via inhibiting nuclear factor-κB (NF-κB) activation. In addition, GEI down-regulated the phosphorylation of Smad2/3 and up-regulated the level of hepatic Smad7, thereby inhibiting TGFβ1/Smad signaling pathway. In conclusion, our findings indicate that GEI can inhibit CCl4-induced hepatic fibrosis, which may be ascribed to its radical scavenging action, antioxidant activity, and modulation of NF-κB and TGF-β1/Smad signaling pathways.

Pratensein attenuates Aβ-induced cognitive deficits in rats: enhancement of synaptic plasticity and cholinergic function.

An isoflavone was isolated from Trifolium pratense using bioassay-guided screening. The structure of this natural compound was elucidated based on its spectral data, and it was identified as pratensein. The protective effect of pratensein was evaluated using a cognitive impairment model induced by injecting amyloid beta (1-42) (Aβ1-42) into the bilateral hippocampus of rats. The results showed that pratensein treatment significantly protected against Aβ1-42-induced cognitive impairments, as evidenced by the improvement in learning and memory and the attenuation of neuronal degeneration and apoptosis in hippocampus. Analysis of the potential mechanisms of action showed that pratensein significantly decreased inflammatory indicators such as MDA, NO, nNOS, IL-1β and TNF-α. Pratensein markedly decreased the content and deposition of β-amyloid peptide through regulating the expressions of Aβ-related genes including APP, BACE1, CatB, NEP and IDE. Moreover, pratensein significantly increased the expressions of synapse plasticity-related proteins, i.e., PSD-95, p-NMDAR1, p-CaMKII, p-PKACβ, PKCγ, p-CREB and BDNF. In addition, pratensein significantly decreased the activity of cholinesterase, then subsequently elevated the level of acetylcholine. In summary, our study indicated that pratensein may have a likely protective effect against Alzheimers disease (AD) via improving synaptic plasticity and increasing cholinesterase activity.

Antiviral activity of methyl helicterate isolated from Helicteres angustifolia (Sterculiaceae) against hepatitis B virus

The anti-HBV effect of methyl helicterate (MH), a triterpenoid isolated from the Chinese herb Helicteres angustifolia, was explored both in vitro and in vivo. In the HBV-transfected cell line HepG2.2.15, the secretion of HBsAg/HBeAg, the levels of HBV DNA and cccDNA, and the amount of viral RNA were significantly decreased after treatment with MH for 144h. In addition, MH had no inhibitory effect on the mitochondrial DNA content. In DHBV-infected ducklings, MH significantly reduced the serum DHBV DNA, liver total viral DNA, and cccDNA levels. Furthermore, analysis of the liver pathological changes confirmed the hepatoprotective effect of MH. These results indicate that MH efficiently inhibits HBV replication both in vitro and in vivo and that MH may be a major bioactive ingredient in H. angustifolia.