Sedum mexicanum Britt. Induces Apoptosis of Primary Rat Activated Hepatic Stellate Cells

Background. Liver fibrosis is a significant liver disease in Asian countries. Sedum mexicanum Britt. (SM) has been claimed to have antihepatitis efficacy. In traditional folk medicine, a solution of boiling water-extracted SM (SME) is consumed to prevent and treat hepatitis. However, its efficacy has not yet been verified. The purpose of this study was to investigate the in vitro effect of SME on hepatoprotection. Methods. Hepatic stellate cells (HSCs) and hepatocytes (HCs) were isolated from the livers of the rats by enzymatic digestion and density gradient centrifugation. Results. Treating the HCs and aHSCs with SME caused a dose-dependent decrease in the viability of aHSCs but not that of HCs. In addition, treatment with SME resulted in apoptosis of aHSCs, as determined by DAPI analysis and flow cytometry. SME also increased the amount of cleaved caspase-3, cleaved caspase-9, and cleaved poly ADP-ribose polymerase (PARP) in aHSCs. Furthermore, SME treatment induced a dose-dependent reduction in Bcl-2 expression and increased the expression of Bax in aHSCs. Conclusions. SME did not cause cytotoxicity in HCs, but it induced apoptosis in aHSCs through the mitochondria-dependent caspase-3 pathway. Therefore, SME may possess therapeutic potential for liver fibrosis

Modeling of Human Hepatic and Gastrointestinal Ethanol Metabolism with Kinetic-Mechanism-Based Full-Rate Equations of the Component Alcohol Dehydrogenase Isozymes and Allozymes

Alcohol dehydrogenase (ADH) is the principal enzyme responsible for the metabolism of ethanol. Human ADH constitutes a complex family of isozymes and allozymes with striking variation in kinetic properties and tissue distribution. The liver and the gastrointestinal tract are the major sites for first-pass metabolism (FPM). The quantitative contributions of ADH isozymes and ethnically distinct allozymes to cellular ethanol metabolism remain poorly understood. To address this issue, kinetic mechanism and the steady-state full-rate equations for recombinant human class I ADH1A, ADH1B (including allozymes ADH1B1, ADH1B2, and ADH1B3), ADH1C (including allozymes ADH1C1 and ADH1C2), class II ADH2, and class IV ADH4 were determined by initial velocity, product inhibition, and dead-end inhibition experiments in 0.1 M sodium phosphate at pH 7.5 and 25 °C. Models of the hepatic and gastrointestinal metabolisms of ethanol were constructed by linear combination of the numerical full-rate equations of the component isozymes and allozymes in target organs. The organ simulations indicate that in homozygous <i>ADH1B*1/*1</i> livers, a representative genotype among ethnically distinct populations due to high prevalence of the allele, major contributors at 1 to 10 mM ethanol are ADH1B1 (45% to 24%) and the ADH1C allozymes (54% to 40%). The simulated activities at 1 to 50 mM ethanol for the gastrointestinal tract (total mucosae of <i>ADH1C*1/*1–ADH4</i> stomach and the <i>ADH1C*1/*1–ADH2</i> duodenum and jejunum) account for 0.68%–0.76% of that for the <i>ADH1B*1/*1–ADH1C*1/*1</i> liver, suggesting gastrointestinal tract plays a relatively minor role in the human FPM of ethanol. Based on the flow-limited sinusoidal perfusion model, the simulated hepatic <i>K</i>_m^app, <i>V</i>_max^app, and <i>C</i>_i at a 95% clearance of ethanol for <i>ADH1B*1/*1–ADH1C*1/*1</i> livers are compatible to that documented in hepatic vein catheterization and pharmacokinetic studies with humans that controlled for the genotypes. The model simulations suggest that slightly higher or similar ethanol elimination rates for <i>ADH1B*2/*2</i> and <i>ADH1B*3/*3</i> individuals compared with those for <i>ADH1B*1/*1</i> individuals may result from higher hepatocellular acetaldehyde

Lysophosphatidic acid alters the expression profiles of angiogenic factors, cytokines, and chemokines in mouse liver sinusoidal endothelial cells.

Lysophosphatidic acid (LPA) is a multi-function glycerophospholipid. LPA affects the proliferation of hepatocytes and stellate cells in vitro, and in a partial hepatectomy induced liver regeneration model, the circulating LPA levels and LPA receptor (LPAR) expression levels in liver tissue are significantly changed. Liver sinusoidal endothelial cells (Lsecs) play an important role during liver regeneration. However, the effects of LPA on Lsecs are not well known. Thus, we investigated the effects of LPA on the expression profiles of angiogenic factors, cytokines, and chemokines in Lsecs.Mouse Lsecs were isolated using CD31-coated magnetic beads. The mRNA expression levels of LPAR's and other target genes were determined by quantitative RT-PCR. The protein levels of angiogenesis factors, cytokines, and chemokines were determined using protein arrays and enzyme immunoassay (EIA). Critical LPAR related signal transduction was verified by using an appropriate chemical inhibitor.LPAR1 and LPAR3 mRNA's were expressed in mouse LPA-treated Lsecs. Treating Lsecs with a physiological level of LPA significantly enhanced the protein levels of angiogenesis related proteins (cyr61 and TIMP-1), cytokines (C5/C5a, M-CSF, and SDF-1), and chemokines (MCP-5, gp130, CCL28, and CXCL16). The LPAR1 and LPAR3 antagonist ki16425 significantly inhibited the LPA-enhanced expression of cyr61, TIMP-1, SDF-1, MCP-5, gp130, CCL28, and CXCL16, but not that of C5/C5a or M-CSF. LPA-induced C5/C5a and M-CSF expression may have been through an indirect regulation mechanism.LPA regulated the expression profiles of angiogenic factors, cytokines, and chemokines in Lsecs that was mediated via LPAR1 and LPAR3 signaling. Most of the factors that were enhanced by LPA have been found to play critical roles during liver regeneration. Thus, these results may prove useful for manipulating LPA effects on liver regeneration

Characterization of Secondary Metabolites from Purple Ipomoea batatas Leaves and Their Effects on Glucose Uptake

Ipomoea batatas has long been used in folk medicine for the treatment of hyperglycemia or as a food additive for the prevention of type 2 diabetes. However, neither the plant extract nor its active components have been evaluated systematically. In this work four crude extracts, including n-hexane- (IBH), 95% MeOH- (IBM), n-BuOH- (IBB), and H2O-soluble (IBW) fractions, were prepared by fractionation of a methanolic extract of purple I. batatas leaves. Twenty-four pure compounds 1–24 were then isolated by various chromatographic techniques and their structures identified from NMR and MS data. Glucose uptake assays in differentiated 3T3-L1 adipocytes and rat primary hepatocytes, as well as western blot analysis, were carried out to evaluate the antidiabetic activity of this species. The IBH crude fraction, with methyl decanoate (22) as a major and active compound, showed the greatest effect on glucose uptake, most likely via activation of Glut4 and regulation of the PI3K/AKT pathway. Quercetin 3-O-β-d-sophoroside (1), quercetin (3), benzyl β-d-glucoside (10), 4-hydroxy-3-methoxybenzaldehyde (12), and methyl decanoate (22) could be important components contributing to the antidiabetic effects. We conclude that purple I. batatas leaves have potential as an antidiabetic plant source and the active constituents 1, 3, 10, 12, and 22 are promising lead candidates for future investigation

Epidemiological survey of Toxoplasma gondii and Neospora caninum infections in dairy goats in Central-Southern Taiwan

Toxoplasma gondii and Neospora caninum are intracellular protozoan parasites that cause reproductive disorders in ruminants and humans. Information on the risk factors of T. gondii and N. caninum infections in goats is very limited in Taiwan. The aim of the study was to investigate the epidemiology and identify the risk factors of these two infections in goats. A total of 630 caprine sera were collected from 42 dairy goat farms and the owners were interviewed by a structured questionnaire. The apparent seroprevalences of T. gondii in farm- and individual- levels were respectively 88.1% and 32.22%, while those of N. caninum were 19.05% and 2.54%, respectively. Toxoplasma gondii B1 gene was identified in 7 feed samples and 8 from the water samples whereas N. caninum was not found. Wooden flooring was the main risk factor for T. gondii infection while the frequency of visits by staff to other farms and the breed of goat were risk factors for N. caninum. The improvement of flooring materials or thorough cleaning, periodic disinfection and maintenance of dryness on the floor are highly recommended for the prevention of T. gondii infection in farmed goats. In addition, unnecessary visits to other farms should be limited to prevent the spread of N. caninum. These factors should be highlighted for the prevention of T. gondii and N. caninum in goats, particularly when raised in intensive housing system with flooring on height

The Contribution of Matrix Metalloproteinase-1 Genotypes to Hepatocellular Carcinoma Susceptibility in Taiwan

[[abstract]]Background/Aim: Metalloproteinases (MMPs) are a family of proteases which have been shown to be overexpressed in various types of cancers. However, the contribution of MMP1 genotype to hepatocellular carcinoma (HCC) has not been well studied. This study aimed to evaluate the contribution of MMP1 promoter 1607 genotype to the risk of HCC in Taiwan, where HCC incidence is relatively high in the world. Materials and Methods: In this case–control study, MMP1 genotype and its interaction with consumption of cigarettes and alcohol in determining HCC risk was investigated among 298 HCC patients and 889 age- and gender-matched healthy controls. Results: The percentages of ever smokers and ever alcohol drinkers were much higher in the case group than in the control group. The percentages of 2G/2G, 1G/2G and 1G/1G for MMP1 promoter 1607 genotype were 37.2%, 38.3% and 24.5% in the HCC group and 34.8%, 44.0% and 21.2% in the control group, respectively (p for trend=0.2048). The allelic frequency distribution analysis showed the variant 1G allele of MMP1 promoter 1607 conferred similar HCC susceptibility as the wild-type 2G allele (odds ratio (OR)=1.01, 95% confidence interval (CI)=0.84-1.22, p=0.8735). As for the gene–lifestyle interaction, there was an obvious protective effect of MMP1 promoter 1607 1G allele on the risk of HCC among non-smokers, but not non-smokers, even alcohol drinkers or non-drinkers. Conclusion: The 1G allele of MMP1 promoter 1607 may have a protective effect on HCC risk for non-smokers in Taiwan and further validations are needed in other population groups. *These Authors contributed equally to this study

Schematic for LPA enhanced expression of angiogenesis factors, cytokines, and chemokines in liver sinusoidal endothelial cells mediated by LPAR1 and LPAR3 signaling.

<p>Schematic for LPA enhanced expression of angiogenesis factors, cytokines, and chemokines in liver sinusoidal endothelial cells mediated by LPAR1 and LPAR3 signaling.</p

LPA effects on angiogenesis factor, cytokine, and chemokines expression are mediated by LPAR1 and LPAR3 signaling.

<p>(A) LPAR1 and LPAR3 signaling effects on LPA induced proteins level. Liver sinusoidal endothelial cells were pre-treated with an inhibitor of LPAR1 and LPAR3, ki16425 (1 uM), for 30 minutes prior 5 uM LPA treatment. After 24 hours, conditioned media derived from vehicle (1% BSA), LPA (5uM) alone, and ki16425 plus LPA treatment were collected for protein level determinations by EIA. Data shown are fold changes of induction with LPA alone versus vehicle treatment, and ki16425 treatment combined with LPA versus vehicle treatment. Results were compared between LPA treatment alone and ki16425 treatment combined with LPA (n = 3); *<i>p</i> < 0.05. (B) Time course for LPA effects on specific genes’ mRNA expressions. Liver sinusoidal endothelial cells were treated with vehicle (1% BSA) or LPA (5 uM). After 4, 8, and 16 hours, total RNA was isolated from vehicle and LPA treated cells for mRNA determinations by qRT-PCR. Data are fold changes of induction with LPA treatment versus vehicle treatment. Results were compared with vehicle treatment (n = 3); *<i>p</i> < 0.05.</p