Bisphenol A sulfonation is impaired in metabolic and liver disease

International Nuclear Information System (INIS)

Yalcin, Emine B.; Kulkarni, Supriya R.; Slitt, Angela L.; King, Roberta

2016-01-01

Background: Bisphenol A (BPA) is a widely used industrial chemical and suspected endocrine disruptor to which humans are ubiquitously exposed. The liver metabolizes and facilitates BPA excretion through glucuronidation and sulfonation. The sulfotransferase enzymes contributing to BPA sulfonation (detected in human and rodents) is poorly understood. Objectives: To determine the impact of metabolic and liver disease on BPA sulfonation in human and mouse livers. Methods: The capacity for BPA sulfonation was determined in human liver samples that were categorized into different stages of metabolic and liver disease (including obesity, diabetes, steatosis, and cirrhosis) and in livers from ob/ob mice. Results: In human liver tissues, BPA sulfonation was substantially lower in livers from subjects with steatosis (23%), diabetes cirrhosis (16%), and cirrhosis (18%), relative to healthy individuals with non-fatty livers (100%). In livers of obese mice (ob/ob), BPA sulfonation was lower (23%) than in livers from lean wild-type controls (100%). In addition to BPA sulfonation activity, Sult1a1 protein expression decreased by 97% in obese mouse livers. Conclusion: Taken together these findings establish a profoundly reduced capacity of BPA elimination via sulfonation in obese or diabetic individuals and in those with fatty or cirrhotic livers versus individuals with healthy livers. - Highlights: • Present study demonstrates that hepatic SULT 1A1/1A3 are primarily sulfonate BPA in mouse and human. • Hepatic BPA sulfonation is profoundly reduced steatosis, diabetes and cirrhosis. • With BPA-S detectable in urine under low or common exposures, these findings are novel and important.

Bisphenol A sulfonation is impaired in metabolic and liver disease

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Yalcin, Emine B.; Kulkarni, Supriya R.; Slitt, Angela L., E-mail: angela_slitt@uri.edu; King, Roberta, E-mail: rking@uri.edu

2016-02-01

Background: Bisphenol A (BPA) is a widely used industrial chemical and suspected endocrine disruptor to which humans are ubiquitously exposed. The liver metabolizes and facilitates BPA excretion through glucuronidation and sulfonation. The sulfotransferase enzymes contributing to BPA sulfonation (detected in human and rodents) is poorly understood. Objectives: To determine the impact of metabolic and liver disease on BPA sulfonation in human and mouse livers. Methods: The capacity for BPA sulfonation was determined in human liver samples that were categorized into different stages of metabolic and liver disease (including obesity, diabetes, steatosis, and cirrhosis) and in livers from ob/ob mice. Results: In human liver tissues, BPA sulfonation was substantially lower in livers from subjects with steatosis (23%), diabetes cirrhosis (16%), and cirrhosis (18%), relative to healthy individuals with non-fatty livers (100%). In livers of obese mice (ob/ob), BPA sulfonation was lower (23%) than in livers from lean wild-type controls (100%). In addition to BPA sulfonation activity, Sult1a1 protein expression decreased by 97% in obese mouse livers. Conclusion: Taken together these findings establish a profoundly reduced capacity of BPA elimination via sulfonation in obese or diabetic individuals and in those with fatty or cirrhotic livers versus individuals with healthy livers. - Highlights: • Present study demonstrates that hepatic SULT 1A1/1A3 are primarily sulfonate BPA in mouse and human. • Hepatic BPA sulfonation is profoundly reduced steatosis, diabetes and cirrhosis. • With BPA-S detectable in urine under low or common exposures, these findings are novel and important.

Metabolism of polybrominated diphenyl ethers and tetrabromobisphenol A by fish liver subcellular fractions in vitro.

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Shen, Mengnan; Cheng, Jie; Wu, Ruohan; Zhang, Shenghu; Mao, Liang; Gao, Shixiang

2012-06-15

Polybrominated diphenyl ethers (PBDEs) and tetrabromobisphenol A (TBBPA) are two major flame retardants that accumulate in fish tissues and are potentially toxic. Their debrominated and oxidated derivatives were also reported in fish tissues although the sources of theses derivatives were unidentified. Our study was to determine whether PBDEs and TBBPA could be metabolized by fish liver subcellular fractions in vitro and to identify what types of metabolites were formed. Liver microsomes and S9 fractions of crucian carp (Carassius auratus) were exposed to 4,4'-dibromodiphenyl ether (BDE 15), 2,2',4,4'-tetrabromodiphenyl ether (BDE 47) or TBBPA solutions for 4h. Exposure of liver subcellular fractions to BDE 15 resulted in the formation of bromophenol and two monohydroxylated dibromodiphenyl ether metabolites. Neither in microsomes nor in S9 studies has revealed the presence of hydroxylated metabolites with BDE 47 exposure which indicated that the oxidation reactions in vitro were hindered by the increased number of bromine substituents on the PBDEs. TBBPA underwent an oxidative cleavage near the central carbon of the molecule, which led to the production of 2,6-dibromo-4-isopropyl-phenol and three unidentified metabolites. Another metabolite of TBBPA characterized as a hexa-brominated compound with three aromatic rings was also found in the liver subcellular fractions. These results suggest that the biotransformation of BDE 15 and TBBPA in fish liver is mediated by cytochrome P450 (CYP450) enzymes, as revealed by the formation of hydroxylated metabolites and oxidative bond cleavage products. Moreover, further studies on the identification of specific CYP450 isozymes involved in the biotransformation revealed that CYP1A was the major enzyme responsible for the biotransformation of BDE 15 and TBBPA in fish liver subcellular fractions and CYP3A4 also played a major role in metabolism of TBBPA. Copyright © 2012 Elsevier B.V. All rights reserved.

Hepatic clearance of 6 polyaromatic aromatic hydrocarbons by isolated trout livers: Prediction from in vitro clearance by liver S9 fractions

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An isolated perfused trout liver preparation was used to evaluate in vitro-to-in vivo metabolism extrapolation procedures for fish. Hepatic clearance (CLH) studies were conducted with six polyaromatic hydrocarbons (PAH) using an experimental design wherein each liver acted as it...

Sphingosine kinase-1, S1P transporter spinster homolog 2 and S1P2 mRNA expressions are increased in liver with advanced fibrosis in human.

Science.gov (United States)

Sato, Masaya; Ikeda, Hitoshi; Uranbileg, Baasanjav; Kurano, Makoto; Saigusa, Daisuke; Aoki, Junken; Maki, Harufumi; Kudo, Hiroki; Hasegawa, Kiyoshi; Kokudo, Norihiro; Yatomi, Yutaka

2016-08-26

The role of sphingosine 1-phosphate (S1P) in liver fibrosis or inflammation was not fully examined in human. Controversy exists which S1P receptors, S1P1 and S1P3 vs S1P2, would be importantly involved in its mechanism. To clarify these matters, 80 patients who received liver resection for hepatocellular carcinoma and 9 patients for metastatic liver tumor were enrolled. S1P metabolism was analyzed in background, non-tumorous liver tissue. mRNA levels of sphingosine kinase 1 (SK1) but not SK2 were increased in livers with fibrosis stages 3-4 compared to those with 0-2 and to normal liver. However, S1P was not increased in advanced fibrotic liver, where mRNA levels of S1P transporter spinster homolog 2 (SPNS2) but not S1P-degrading enzymes were enhanced. Furthermore, mRNA levels of S1P2 but not S1P1 or S1P3 were increased in advanced fibrotic liver. These increased mRNA levels of SK1, SPNS2 and S1P2 in fibrotic liver were correlated with α-smooth muscle actin mRNA levels in liver, and with serum ALT levels. In conclusion, S1P may be actively generated, transported to outside the cells, and bind to its specific receptor in human liver to play a role in fibrosis or inflammation. Altered S1P metabolism in fibrotic liver may be their therapeutic target.

Energy Metabolism in the Liver

OpenAIRE

Rui, Liangyou

2014-01-01

The liver is an essential metabolic organ, and its metabolic activity is tightly controlled by insulin and other metabolic hormones. Glucose is metabolized into pyruvate through glycolysis in the cytoplasm, and pyruvate is completely oxidized to generate ATP through the TCA cycle and oxidative phosphorylation in the mitochondria. In the fed state, glycolytic products are used to synthesize fatty acids through de novo lipogenesis. Long-chain fatty acids are incorporated into triacylglycerol, p...

PCSK9 Induces CD36 Degradation and Affects Long-Chain Fatty Acid Uptake and Triglyceride Metabolism in Adipocytes and in Mouse Liver.

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Demers, Annie; Samami, Samaneh; Lauzier, Benjamin; Des Rosiers, Christine; Ngo Sock, Emilienne Tudor; Ong, Huy; Mayer, Gaetan

2015-12-01

Proprotein convertase subtilisin/kexin type 9 (PCSK9) promotes the degradation of the low-density lipoprotein receptor thereby elevating plasma low-density lipoprotein cholesterol levels and the risk of coronary heart disease. Thus, the use of PCSK9 inhibitors holds great promise to prevent heart disease. Previous work found that PCSK9 is involved in triglyceride metabolism, independently of its action on low-density lipoprotein receptor, and that other yet unidentified receptors could mediate this effect. Therefore, we assessed whether PCSK9 enhances the degradation of CD36, a major receptor involved in transport of long-chain fatty acids and triglyceride storage. Overexpressed or recombinant PCSK9 induced CD36 degradation in cell lines and primary adipocytes and reduced the uptake of the palmitate analog Bodipy FL C16 and oxidized low-density lipoprotein in 3T3-L1 adipocytes and hepatic HepG2 cells, respectively. Surface plasmon resonance, coimmunoprecipitation, confocal immunofluorescence microscopy, and protein degradation pathway inhibitors revealed that PCSK9 directly interacts with CD36 and targets the receptor to lysosomes through a mechanism involving the proteasome. Importantly, the level of CD36 protein was increased by >3-fold upon small interfering RNA knockdown of endogenous PCSK9 in hepatic cells and similarly increased in the liver and visceral adipose tissue of Pcsk9(-/-) mice. In Pcsk9(-/-) mice, increased hepatic CD36 was correlated with an amplified uptake of fatty acid and accumulation of triglycerides and lipid droplets. Our results demonstrate an important role of PCSK9 in modulating the function of CD36 and triglyceride metabolism. PCSK9-mediated CD36 degradation may serve to limit fatty acid uptake and triglyceride accumulation in tissues, such as the liver. © 2015 American Heart Association, Inc.

Genetic networks of liver metabolism revealed by integration of metabolic and transcriptional profiling.

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Christine T Ferrara

2008-03-01

Full Text Available Although numerous quantitative trait loci (QTL influencing disease-related phenotypes have been detected through gene mapping and positional cloning, identification of the individual gene(s and molecular pathways leading to those phenotypes is often elusive. One way to improve understanding of genetic architecture is to classify phenotypes in greater depth by including transcriptional and metabolic profiling. In the current study, we have generated and analyzed mRNA expression and metabolic profiles in liver samples obtained in an F2 intercross between the diabetes-resistant C57BL/6 leptin(ob/ob and the diabetes-susceptible BTBR leptin(ob/ob mouse strains. This cross, which segregates for genotype and physiological traits, was previously used to identify several diabetes-related QTL. Our current investigation includes microarray analysis of over 40,000 probe sets, plus quantitative mass spectrometry-based measurements of sixty-seven intermediary metabolites in three different classes (amino acids, organic acids, and acyl-carnitines. We show that liver metabolites map to distinct genetic regions, thereby indicating that tissue metabolites are heritable. We also demonstrate that genomic analysis can be integrated with liver mRNA expression and metabolite profiling data to construct causal networks for control of specific metabolic processes in liver. As a proof of principle of the practical significance of this integrative approach, we illustrate the construction of a specific causal network that links gene expression and metabolic changes in the context of glutamate metabolism, and demonstrate its validity by showing that genes in the network respond to changes in glutamine and glutamate availability. Thus, the methods described here have the potential to reveal regulatory networks that contribute to chronic, complex, and highly prevalent diseases and conditions such as obesity and diabetes.

Gender Differences in Adipocyte Metabolism and Liver Cancer Progression

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Otto Ka-Wing Cheung

2016-09-01

Full Text Available Liver cancer is the third most common cancer type and the second leading cause of deaths in men. Large population studies have demonstrated remarkable gender disparities in the incidence and the cumulative risk of liver cancer. A number of emerging risk factors regarding metabolic alterations associated with obesity, diabetes and dyslipidemia have been ascribed to the progression of non-alcoholic fatty liver diseases (NAFLD and ultimately liver cancer. The deregulation of fat metabolism derived from excessive insulin, glucose and lipid promotes cancer-causing inflammatory signaling and oxidative stress, which eventually triggers the uncontrolled hepatocellular proliferation. This review presents the current standing on the gender differences in body fat compositions and their mechanistic linkage with the development of NAFLD-related liver cancer, with an emphasis on genetic, epigenetic and microRNA control. The potential roles of sex hormones in instructing adipocyte metabolic programs may help unravel the mechanisms underlying gender dimorphism in liver cancer and identify the metabolic targets for disease management.

Application of localized 31P MRS saturation transfer at 7 T for measurement of ATP metabolism in the liver: reproducibility and initial clinical application in patients with non-alcoholic fatty liver disease

International Nuclear Information System (INIS)

Valkovic, Ladislav; Gajdosik, Martin; Chmelik, Marek; Trattnig, Siegfried; Traussnigg, Stefan; Kienbacher, Christian; Trauner, Michael; Wolf, Peter; Krebs, Michael; Bogner, Wolfgang; Krssak, Martin

2014-01-01

Saturation transfer (ST) phosphorus MR spectroscopy ( 31 P MRS) enables in vivo insight into energy metabolism and thus could identify liver conditions currently diagnosed only by biopsy. This study assesses the reproducibility of the localized 31 P MRS ST in liver at 7 T and tests its potential for noninvasive differentiation of non-alcoholic fatty liver (NAFL) and steatohepatitis (NASH). After the ethics committee approval, reproducibility of the localized 31 P MRS ST at 7 T and the biological variation of acquired hepato-metabolic parameters were assessed in healthy volunteers. Subsequently, 16 suspected NAFL/NASH patients underwent MRS measurements and diagnostic liver biopsy. The Pi-to-ATP exchange parameters were compared between the groups by a Mann-Whitney U test and related to the liver fat content estimated by a single-voxel proton ( 1 H) MRS, measured at 3 T. The mean exchange rate constant (k) in healthy volunteers was 0.31 ± 0.03 s -1 with a coefficient of variation of 9.0 %. Significantly lower exchange rates (p -1 ) when compared to healthy volunteers, and NAFL patients (k = 0.30 ± 0.05 s -1 ). Significant correlation was found between the k value and the liver fat content (r = 0.824, p 31 P MRS ST technique provides a tool for gaining insight into hepatic ATP metabolism and could contribute to the differentiation of NAFL and NASH. (orig.)

Serum aminotransferases in nonalcoholic fatty liver disease are a signature of liver metabolic perturbations at the amino acid and Krebs cycle level.

Science.gov (United States)

Sookoian, Silvia; Castaño, Gustavo O; Scian, Romina; Fernández Gianotti, Tomas; Dopazo, Hernán; Rohr, Cristian; Gaj, Graciela; San Martino, Julio; Sevic, Ina; Flichman, Diego; Pirola, Carlos J

2016-02-01

Extensive epidemiologic studies have shown that cardiovascular disease and the metabolic syndrome (MetS) are associated with serum concentrations of liver enzymes; however, fundamental characteristics of this relation are currently unknown. We aimed to explore the role of liver aminotransferases in nonalcoholic fatty liver disease (NAFLD) and MetS. Liver gene- and protein-expression changes of aminotransferases, including their corresponding isoforms, were evaluated in a case-control study of patients with NAFLD (n = 42), which was proven through a biopsy (control subjects: n = 10). We also carried out a serum targeted metabolite profiling to the glycolysis, gluconeogenesis, and Krebs cycle (n = 48) and an exploration by the next-generation sequencing of aminotransferase genes (n = 96). An in vitro study to provide a biological explanation of changes in the transcriptional level and enzymatic activity of aminotransferases was included. Fatty liver was associated with a deregulated liver expression of aminotransferases, which was unrelated to the disease severity. Metabolite profiling showed that serum aminotransferase concentrations are a signature of liver metabolic perturbations, particularly at the amino acid metabolism and Krebs cycle level. A significant and positive association between systolic hypertension and liver expression levels of glutamic-oxaloacetic transaminase 2 (GOT2) messenger RNA (Spearman R = 0.42, P = 0.03) was observed. The rs6993 located in the 3' untranslated region of the GOT2 locus was significantly associated with features of the MetS, including arterial hypertension [P = 0.028; OR: 2.285 (95% CI: 1.024, 5.09); adjusted by NAFLD severity] and plasma lipid concentrations. In the context of an abnormal hepatic triglyceride accumulation, circulating aminotransferases rise as a consequence of the need for increased reactions of transamination to cope with the liver metabolic derangement that is associated with greater gluconeogenesis and

Disturbed Vitamin A Metabolism in Non-Alcoholic Fatty Liver Disease (NAFLD

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Ali Saeed

2017-12-01

Full Text Available Vitamin A is required for important physiological processes, including embryogenesis, vision, cell proliferation and differentiation, immune regulation, and glucose and lipid metabolism. Many of vitamin A’s functions are executed through retinoic acids that activate transcriptional networks controlled by retinoic acid receptors (RARs and retinoid X receptors (RXRs.The liver plays a central role in vitamin A metabolism: (1 it produces bile supporting efficient intestinal absorption of fat-soluble nutrients like vitamin A; (2 it produces retinol binding protein 4 (RBP4 that distributes vitamin A, as retinol, to peripheral tissues; and (3 it harbors the largest body supply of vitamin A, mostly as retinyl esters, in hepatic stellate cells (HSCs. In times of inadequate dietary intake, the liver maintains stable circulating retinol levels of approximately 2 μmol/L, sufficient to provide the body with this vitamin for months. Liver diseases, in particular those leading to fibrosis and cirrhosis, are associated with impaired vitamin A homeostasis and may lead to vitamin A deficiency. Liver injury triggers HSCs to transdifferentiate to myofibroblasts that produce excessive amounts of extracellular matrix, leading to fibrosis. HSCs lose the retinyl ester stores in this process, ultimately leading to vitamin A deficiency. Non-alcoholic fatty liver disease (NAFLD is the hepatic manifestation of metabolic syndrome and is a spectrum of conditions ranging from benign hepatic steatosis to non-alcoholic steatohepatitis (NASH; it may progress to cirrhosis and liver cancer. NASH is projected to be the main cause of liver failure in the near future. Retinoic acids are key regulators of glucose and lipid metabolism in the liver and adipose tissue, but it is unknown whether impaired vitamin A homeostasis contributes to or suppresses the development of NAFLD. A genetic variant of patatin-like phospholipase domain-containing 3 (PNPLA3-I148M is the most prominent

Studies of liver-specific metabolic reactions with 15N. 1

International Nuclear Information System (INIS)

Hirschberg, K.; Jung, K.; Faust, H.; Matkowitz, R.

1987-01-01

The 15 N tracer technique was used to investigate liver-specific reactions (urea and hippurate synthesis) for studying the metabolism in the healthy and damaged pig liver. After [ 15 N]ammonium chloride administration the tracer distribution on non-protein compounds of serum and urine was followed. Blood samplings before and after liver passage rendered possible a direct analysis of the [ 15 N]ammonium metabolism. The thioacetamide-induced liver damage was used as model for an acute liver intoxication. The capacity for urea synthesis was not influenced by means of this noxious substance, but the metabolism of amino acids and hippuric acid. The considerably depressed excretion of [ 15 N]hippurate seems to be a suitable indicator of liver disfunction. (author)

Application of localized {sup 31}P MRS saturation transfer at 7 T for measurement of ATP metabolism in the liver: reproducibility and initial clinical application in patients with non-alcoholic fatty liver disease

Energy Technology Data Exchange (ETDEWEB)

Valkovic, Ladislav [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Slovak Academy of Sciences, Department of Imaging Methods, Institute of Measurement Science, Bratislava (Slovakia); Gajdosik, Martin; Chmelik, Marek; Trattnig, Siegfried [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Traussnigg, Stefan; Kienbacher, Christian; Trauner, Michael [Medical University of Vienna, Division of Gastroenterology and Hepatology, Department of Internal Medicine III, Vienna (Austria); Wolf, Peter; Krebs, Michael [Medical University of Vienna, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Vienna (Austria); Bogner, Wolfgang [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Harvard Medical School, Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Boston, MA (United States); Krssak, Martin [Medical University of Vienna, High Field MR Centre, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Medical University of Vienna, Division of Endocrinology and Metabolism, Department of Internal Medicine III, Vienna (Austria)

2014-07-15

Saturation transfer (ST) phosphorus MR spectroscopy ({sup 31}P MRS) enables in vivo insight into energy metabolism and thus could identify liver conditions currently diagnosed only by biopsy. This study assesses the reproducibility of the localized {sup 31}P MRS ST in liver at 7 T and tests its potential for noninvasive differentiation of non-alcoholic fatty liver (NAFL) and steatohepatitis (NASH). After the ethics committee approval, reproducibility of the localized {sup 31}P MRS ST at 7 T and the biological variation of acquired hepato-metabolic parameters were assessed in healthy volunteers. Subsequently, 16 suspected NAFL/NASH patients underwent MRS measurements and diagnostic liver biopsy. The Pi-to-ATP exchange parameters were compared between the groups by a Mann-Whitney U test and related to the liver fat content estimated by a single-voxel proton ({sup 1}H) MRS, measured at 3 T. The mean exchange rate constant (k) in healthy volunteers was 0.31 ± 0.03 s{sup -1} with a coefficient of variation of 9.0 %. Significantly lower exchange rates (p < 0.01) were found in NASH patients (k = 0.17 ± 0.04 s{sup -1}) when compared to healthy volunteers, and NAFL patients (k = 0.30 ± 0.05 s{sup -1}). Significant correlation was found between the k value and the liver fat content (r = 0.824, p < 0.01). Our data suggest that the {sup 31}P MRS ST technique provides a tool for gaining insight into hepatic ATP metabolism and could contribute to the differentiation of NAFL and NASH. (orig.)

Fatty Liver Index and Lipid Accumulation Product Can Predict Metabolic Syndrome in Subjects without Fatty Liver Disease

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Yuan-Lung Cheng

2017-01-01

Full Text Available Background. Fatty liver index (FLI and lipid accumulation product (LAP are indexes originally designed to assess the risk of fatty liver and cardiovascular disease, respectively. Both indexes have been proven to be reliable markers of subsequent metabolic syndrome; however, their ability to predict metabolic syndrome in subjects without fatty liver disease has not been clarified. Methods. We enrolled consecutive subjects who received health check-up services at Taipei Veterans General Hospital from 2002 to 2009. Fatty liver disease was diagnosed by abdominal ultrasonography. The ability of the FLI and LAP to predict metabolic syndrome was assessed by analyzing the area under the receiver operating characteristic (AUROC curve. Results. Male sex was strongly associated with metabolic syndrome, and the LAP and FLI were better than other variables to predict metabolic syndrome among the 29,797 subjects. Both indexes were also better than other variables to detect metabolic syndrome in subjects without fatty liver disease (AUROC: 0.871 and 0.879, resp., and the predictive power was greater among women. Conclusion. Metabolic syndrome increases the cardiovascular disease risk. The FLI and LAP could be used to recognize the syndrome in both subjects with and without fatty liver disease who require lifestyle modifications and counseling.

Pharmacokinetics and N-acetylation metabolism of S-methyl-l-cysteine and trans-S-1-propenyl-l-cysteine in rats and dogs.

Science.gov (United States)

Amano, Hirotaka; Kazamori, Daichi; Itoh, Kenji

2016-11-01

1. Pharmacokinetics and N-acetylation metabolism of S-methyl-L-cysteine (SMC) and trans-S-1-propenyl-L-cysteine (S1PC) were examined in rats and dogs. SMC and S1PC (2-5 mg/kg) were well absorbed in both species with high bioavailability (88-100%). 2. SMC and S1PC were excreted only to a small extent in the urine of rats and dogs. The small renal clearance values (l/h/kg) indicated the extensive renal reabsorption of SMC and S1PC, which potentially contributed to their long elimination half-lives (>5 h) in dogs. 3. S1PC, but not SMC, underwent N-acetylation extensively in vivo, which can be explained by the relative activities of N-acetylation of S1PC/SMC and deacetylation of their N-acetylated forms, N-acetyl-S1PC/N-acetyl-SMC, in the liver and kidney in vitro. The activities for S1PC N-acetylation were similar to or higher than those for N-acetyl-S1PC deacetylation in liver S9 fractions of rat and dog, whereas liver and kidney S9 fractions of rat and dog had little activity for SMC N-acetylation or considerably higher activities for N-acetyl-SMC deacetylation. 4. Our study demonstrated that the pharmacokinetics of SMC and S1PC in rats and dogs was characterized by high bioavailability and extensive renal reabsorption; however, the extent of undergoing the N-acetylation metabolism was extremely different between SMC and S1PC.

Recellularization of rat liver: An in vitro model for assessing human drug metabolism and liver biology.

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Matthew J Robertson

Full Text Available Liver-like organoids that recapitulate the complex functions of the whole liver by combining cells, scaffolds, and mechanical or chemical cues are becoming important models for studying liver biology and drug metabolism. The advantages of growing cells in three-dimensional constructs include enhanced cell-cell and cell-extracellular matrix interactions and preserved cellular phenotype including, prevention of de-differentiation. In the current study, biomimetic liver constructs were made via perfusion decellularization of rat liver, with the goal of maintaining the native composition and structure of the extracellular matrix. We optimized our decellularization process to produce liver scaffolds in which immunogenic residual DNA was removed but glycosaminoglycans were maintained. When the constructs were recellularized with rat or human liver cells, the cells remained viable, capable of proliferation, and functional for 28 days. Specifically, the cells continued to express cytochrome P450 genes and maintained their ability to metabolize a model drug, midazolam. Microarray analysis showed an upregulation of genes involved in liver regeneration and fibrosis. In conclusion, these liver constructs have the potential to be used as test beds for studying liver biology and drug metabolism.

Lack of the Lysosomal Membrane Protein, GLMP, in Mice Results in Metabolic Dysregulation in Liver.

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Xiang Yi Kong

Full Text Available Ablation of glycosylated lysosomal membrane protein (GLMP, formerly known as NCU-G1 has been shown to cause chronic liver injury which progresses into liver fibrosis in mice. Both lysosomal dysfunction and chronic liver injury can cause metabolic dysregulation. Glmp gt/gt mice (formerly known as Ncu-g1gt/gt mice were studied between 3 weeks and 9 months of age. Body weight gain and feed efficiency of Glmp gt/gt mice were comparable to wild type siblings, only at the age of 9 months the Glmp gt/gt siblings had significantly reduced body weight. Reduced size of epididymal fat pads was accompanied by hepatosplenomegaly in Glmp gt/gt mice. Blood analysis revealed reduced levels of blood glucose, circulating triacylglycerol and non-esterified fatty acids in Glmp gt/gt mice. Increased flux of glucose, increased de novo lipogenesis and lipid accumulation were detected in Glmp gt/gt primary hepatocytes, as well as elevated triacylglycerol levels in Glmp gt/gt liver homogenates, compared to hepatocytes and liver from wild type mice. Gene expression analysis showed an increased expression of genes involved in fatty acid uptake and lipogenesis in Glmp gt/gt liver compared to wild type. Our findings are in agreement with the metabolic alterations observed in other mouse models lacking lysosomal proteins, and with alterations characteristic for advanced chronic liver injury.

Serum Matrix Metalloproteinase-9 and Tissue Inhibitor of Metalloproteinase-1 Expression in Patients with Non-alcoholic Fatty Liver Disease

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Taner Akyol

2015-06-01

Full Text Available Non-alcoholic fatty liver disease (NAFLD is the most common chronic liver disease in developed countries. NAFLD may progress to non-alcoholic steatohepatitis (NASH and cirrhosis. Emerging evidence suggests that NAFLD is the hepatic manifestation of metabolic syndrome (MetS. NAFLD is closely linked to MetS, with a significant increase in cardiovascular risk. Several matrix metalloproteinases (MMPs and tissue inhibitors of MMPs (TIMPs play important roles in the pathophysiology of atherosclerosis and liver fibrosis. In this study we investigated the usefulness of serum metalloproteinases as noninvasive markers of NAFLD. Forty-six patients with NAFLD and twenty-six healthy controls were enrolled into the study, in Gulhane Military Medical Academy, Haydarpasa Training Hospital. Liver biopsies were performed on all patients with NAFLD and histopathological evaluations were made by an experienced pathologist. All NAFLD patients were divided into 2 subgroups according to MetS status using ATP III criteria. MMP-9 and TIMP-1 were studied in serum samples of all groups. Results were compared between both groups and subgroups. In this study, the NAFLD and control groups did not differ significantly on MMP-9, TIMP-1 and TIMP-1/MMP-9 ratio (p > 0.05. However, we found a significant relationship between the HOMA and TIMP-1 (p<0.05. Moreover, MMP-9 and TIMP-1/MMP-9 levels were significantly correlated with waist circumference (p<0.05. Our findings are not sufficient to suggest that MMP-9, TIMP-1 and TIMP-1/MMP-9 ratio might be used as noninvasive biochemical diagnostic tests among NAFLD patients. [Dis Mol Med 2015; 3(2.000: 11-17

Association of the components of the metabolic syndrome with non- alcoholic fatty liver disease among normal-weight, overweight and obese children and adolescents

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Kelishadi Roya

2009-12-01

Full Text Available Abstract Objectives This study aimed to determine the prevalence of the metabolic syndrome, abnormalities of liver enzymes and sonographic fatty liver, as well as the inter-related associations in normal weight, overweight and obese children and adolescents. Methods This cross-sectional study was conducted among a sample of 1107 students (56.1% girls, aged 6-18 years in Isfahan, Iran. In addition to physical examination, fasting blood glucose, serum lipid profile and liver enzymes were determined. Liver sonography was performed among 931 participants. These variables were compared among participants with different body mass index (BMI categories. Results From lower to higher BMI category, alanine aminotransferase (ALT, total cholesterol, LDL-cholesterol, triglycerides and systolic blood pressure increased, and HDL-cholesterol decreased significantly. Elevated ALT, aspartate aminotransferase (AST and alkaline phosphatase (ALP were documented in respectively 4.1%, 6.6% and 9.8% of normal weight group. The corresponding figure was 9.5%, 9.8% and 9.1% in overweight group, and 16.9%, 14.9% and 10.8% in obese group, respectively. In all BMI categories, ALT increased significantly by increasing the number of the components of the metabolic syndrome. Odds ratio for elevated liver enzymes and sonographic fatty liver increased significantly with higher number of the components of the metabolic syndrome and higher BMI categories before and after adjustment for age. Conclusions Because of the interrelationship of biochemical and sonographic indexes of fatty liver with the components of the metabolic syndrome, and with increase in their number, it is suggested to determine the clinical impact of such association in future longitudinal studies.

Actions of juglone on energy metabolism in the rat liver

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Saling, Simoni Cristina; Comar, Jurandir Fernando; Mito, Marcio Shigueaki; Peralta, Rosane Marina; Bracht, Adelar, E-mail: adebracht@uol.com.br

2011-12-15

Juglone is a phenolic compound used in popular medicine as a phytotherapic to treat inflammatory and infectious diseases. However, it also acts as an uncoupler of oxidative phosphorylation in isolated liver mitochondria and, thus, may interfere with the hepatic energy metabolism. The purpose of this work was to evaluate the effect of juglone on several metabolic parameters in the isolated perfused rat liver. Juglone, in the concentration range of 5 to 50 {mu}M, stimulated glycogenolysis, glycolysis and oxygen uptake. Gluconeogenesis from both lactate and alanine was inhibited with half-maximal effects at the concentrations of 14.9 and 15.7 {mu}M, respectively. The overall alanine transformation was increased by juglone, as indicated by the stimulated release of ammonia, urea, L-glutamate, lactate and pyruvate. A great increase (9-fold) in the tissue content of {alpha}-ketoglutarate was found, without a similar change in the L-glutamate content. The tissue contents of ATP were decreased, but those of ADP and AMP were increased. Experiments with isolated mitochondria fully confirmed previous notions about the uncoupling action of juglone. It can be concluded that juglone is active on metabolism at relatively low concentrations. In this particular it resembles more closely the classical uncoupler 2,4-dinitrophenol. Ingestion of high doses of juglone, thus, presents the same risks as the ingestion of 2,4-dinitrophenol which comprise excessive compromising of ATP production, hyperthermia and even death. Low doses, i.e., moderate consumption of natural products containing juglone, however, could be beneficial to health if one considers recent reports about the consequences of chronic mild uncoupling. -- Highlights: Black-Right-Pointing-Pointer We investigated how juglone acts on liver metabolism. Black-Right-Pointing-Pointer The actions on hepatic gluconeogenesis, glycolysis and ureogenesis. Black-Right-Pointing-Pointer Juglone stimulates glycolysis and ureagenesis and

Actions of juglone on energy metabolism in the rat liver

International Nuclear Information System (INIS)

Saling, Simoni Cristina; Comar, Jurandir Fernando; Mito, Márcio Shigueaki; Peralta, Rosane Marina; Bracht, Adelar

2011-01-01

Juglone is a phenolic compound used in popular medicine as a phytotherapic to treat inflammatory and infectious diseases. However, it also acts as an uncoupler of oxidative phosphorylation in isolated liver mitochondria and, thus, may interfere with the hepatic energy metabolism. The purpose of this work was to evaluate the effect of juglone on several metabolic parameters in the isolated perfused rat liver. Juglone, in the concentration range of 5 to 50 μM, stimulated glycogenolysis, glycolysis and oxygen uptake. Gluconeogenesis from both lactate and alanine was inhibited with half-maximal effects at the concentrations of 14.9 and 15.7 μM, respectively. The overall alanine transformation was increased by juglone, as indicated by the stimulated release of ammonia, urea, L-glutamate, lactate and pyruvate. A great increase (9-fold) in the tissue content of α-ketoglutarate was found, without a similar change in the L-glutamate content. The tissue contents of ATP were decreased, but those of ADP and AMP were increased. Experiments with isolated mitochondria fully confirmed previous notions about the uncoupling action of juglone. It can be concluded that juglone is active on metabolism at relatively low concentrations. In this particular it resembles more closely the classical uncoupler 2,4-dinitrophenol. Ingestion of high doses of juglone, thus, presents the same risks as the ingestion of 2,4-dinitrophenol which comprise excessive compromising of ATP production, hyperthermia and even death. Low doses, i.e., moderate consumption of natural products containing juglone, however, could be beneficial to health if one considers recent reports about the consequences of chronic mild uncoupling. -- Highlights: ► We investigated how juglone acts on liver metabolism. ► The actions on hepatic gluconeogenesis, glycolysis and ureogenesis. ► Juglone stimulates glycolysis and ureagenesis and inhibits gluconeogenesis. ► The cellular ATP content is diminished. ► Juglone can

Associations between Zinc Deficiency and Metabolic Abnormalities in Patients with Chronic Liver Disease

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Takashi Himoto

2018-01-01

Full Text Available Zinc (Zn is an essential trace element which has favorable antioxidant, anti-inflammatory, and apoptotic effects. The liver mainly plays a crucial role in maintaining systemic Zn homeostasis. Therefore, the occurrence of chronic liver diseases, such as chronic hepatitis, liver cirrhosis, or fatty liver, results in the impairment of Zn metabolism, and subsequently Zn deficiency. Zn deficiency causes plenty of metabolic abnormalities, including insulin resistance, hepatic steatosis and hepatic encephalopathy. Inversely, metabolic abnormalities like hypoalbuminemia in patients with liver cirrhosis often result in Zn deficiency. Recent studies have revealed the putative mechanisms by which Zn deficiency evokes a variety of metabolic abnormalities in chronic liver disease. Zn supplementation has shown beneficial effects on such metabolic abnormalities in experimental models and actual patients with chronic liver disease. This review summarizes the pathogenesis of metabolic abnormalities deriving from Zn deficiency and the favorable effects of Zn administration in patients with chronic liver disease. In addition, we also highlight the interactions between Zn and other trace elements, vitamins, amino acids, or hormones in such patients.

A20 modulates lipid metabolism and energy production to promote liver regeneration.

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Scott M Damrauer

2011-03-01

Full Text Available Liver regeneration is clinically of major importance in the setting of liver injury, resection or transplantation. We have demonstrated that the NF-κB inhibitory protein A20 significantly improves recovery of liver function and mass following extended liver resection (LR in mice. In this study, we explored the Systems Biology modulated by A20 following extended LR in mice.We performed transcriptional profiling using Affymetrix-Mouse 430.2 arrays on liver mRNA retrieved from recombinant adenovirus A20 (rAd.A20 and rAd.βgalactosidase treated livers, before and 24 hours after 78% LR. A20 overexpression impacted 1595 genes that were enriched for biological processes related to inflammatory and immune responses, cellular proliferation, energy production, oxidoreductase activity, and lipid and fatty acid metabolism. These pathways were modulated by A20 in a manner that favored decreased inflammation, heightened proliferation, and optimized metabolic control and energy production. Promoter analysis identified several transcriptional factors that implemented the effects of A20, including NF-κB, CEBPA, OCT-1, OCT-4 and EGR1. Interactive scale-free network analysis captured the key genes that delivered the specific functions of A20. Most of these genes were affected at basal level and after resection. We validated a number of A20's target genes by real-time PCR, including p21, the mitochondrial solute carriers SLC25a10 and SLC25a13, and the fatty acid metabolism regulator, peroxisome proliferator activated receptor alpha. This resulted in greater energy production in A20-expressing livers following LR, as demonstrated by increased enzymatic activity of cytochrome c oxidase, or mitochondrial complex IV.This Systems Biology-based analysis unravels novel mechanisms supporting the pro-regenerative function of A20 in the liver, by optimizing energy production through improved lipid/fatty acid metabolism, and down-regulated inflammation. These findings

Lactate metabolism in chronic liver disease

DEFF Research Database (Denmark)

Jeppesen, Johanne B; Mortensen, Christian; Bendtsen, Flemming

2013-01-01

Background. In the healthy liver there is a splanchnic net-uptake of lactate caused by gluconeogenesis. It has previously been shown that patients with acute liver failure in contrast have a splanchnic release of lactate caused by a combination of accelerated glycolysis in the splanchnic region...... and a reduction in hepatic gluconeogenesis. Aims. The aims of the present study were to investigate lactate metabolism and kinetics in patients with chronic liver disease compared with a control group with normal liver function. Methods. A total of 142 patients with chronic liver disease and 14 healthy controls...... underwent a liver vein catheterization. Blood samples from the femoral artery and the hepatic and renal veins were simultaneously collected before and after stimulation with galactose. Results. The fasting lactate levels, both in the hepatic vein and in the femoral artery, were higher in the patients than...

Liver enzymes and markers of inflammation in Nigerian adults with metabolic syndrome

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Udenze Ifeoma Christiana

2015-01-01

Full Text Available Aims and objectives: The aim of this study is to determine the plasma levels of the liver enzymes alanine aminotransferase (ALT, aspartate aminotransferase (AST, alkaline phosphatase (ALP, gamma-glutamyl transferase (GGT, and lactate dehydrogenase (LDH in people with metabolic syndrome and to determine the association between the liver enzymes and obesity, insulin resistance, interleukin 6 (IL-6, and C-reactive protein (CRP in adult Nigerians with metabolic syndrome. Materials and Methods: This was a case control study of 50 adult men and women with metabolic syndrome, and 50 age- and sex-matched males and females without metabolic syndrome. Metabolic syndrome was defined based on the National Cholesterol Education Program (NCEP-Adult Treatment Panel III (ATPIII criteria. Written informed consent was obtained from the participants. Sociodemographic and clinical data were collected using a structured questionnaire. Venous blood was collected after an overnight fast. The ethics committee of the Lagos University Teaching Hospital in Lagos, Nigeria, approved the study protocol. Comparison of continuous variables was done using the student′s t-test. Regression and correlation analysis were used to determine the associations between variables. Statistical significance was set at P < 0.05. Results: There was a statistically significant increase in the liver enzymes ALP (P = 0.031, ALT (P = 0.019, and GGT (P = 0.037, as well as in the inflammatory markers CRP (P = 0.019 and the cytokine IL-6 (P = 0.040 between the two study groups. ALP and ALT showed significant correlation with waist circumference, BMI, fasting insulin, and waist/hip ratio (P < 0.05. Multivariate regression also identified ALT, AST, and ALP to be associated with IL-6 and CRP (P < 0.05. Conclusion: Liver enzyme levels were increased in metabolic syndrome and associated with obesity, fasting insulin, and CRP. Elevated liver enzymes may indicate dysmetabolism and increased

Prioritizing Popular Proteins in Liver Cancer: Remodelling One-Carbon Metabolism.

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Mora, María Isabel; Molina, Manuela; Odriozola, Leticia; Elortza, Félix; Mato, José María; Sitek, Barbara; Zhang, Pumin; He, Fuchu; Latasa, María Uxue; Ávila, Matías Antonio; Corrales, Fernando José

2017-12-01

Primary liver cancer (HCC) is recognized as the fifth most common neoplasm and the second leading cause of cancer death worldwide. Most risk factors are known, and the molecular pathogenesis has been widely studied in the past decade; however, the underlying molecular mechanisms remain to be unveiled, as they will facilitate the definition of novel biomarkers and clinical targets for more effective patient management. We utilize the B/D-HPP popular protein strategy. We report a list of popular proteins that have been highly cocited with the expression "liver cancer". Several enzymes highlight the known metabolic remodeling of liver cancer cells, four of which participate in one-carbon metabolism. This pathway is central to the maintenance of differentiated hepatocytes, as it is considered the connection between intermediate metabolism and epigenetic regulation. We designed a targeted selective reaction monitoring (SRM) method to follow up one-carbon metabolism adaptation in mouse HCC and in regenerating liver following exposure to CCl 4 . This method allows systematic monitoring of one-carbon metabolism and could prove useful in the follow-up of HCC and of chronically liver-diseased patients (cirrhosis) at risk of HCC. The SRM data are available via ProteomeXchange in PASSEL (PASS01060).

Osteopontin regulates the cross-talk between phosphatidylcholine and cholesterol metabolism in mouse liver.

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Nuñez-Garcia, Maitane; Gomez-Santos, Beatriz; Buqué, Xabier; García-Rodriguez, Juan L; Romero, Marta R; Marin, Jose J G; Arteta, Beatriz; García-Monzón, Carmelo; Castaño, Luis; Syn, Wing-Kin; Fresnedo, Olatz; Aspichueta, Patricia

2017-09-01

Osteopontin (OPN) is involved in different liver pathologies in which metabolic dysregulation is a hallmark. Here, we investigated whether OPN could alter liver, and more specifically hepatocyte, lipid metabolism and the mechanism involved. In mice, lack of OPN enhanced cholesterol 7α-hydroxylase (CYP7A1) levels and promoted loss of phosphatidylcholine (PC) content in liver; in vivo treatment with recombinant (r)OPN caused opposite effects. rOPN directly decreased CYP7A1 levels through activation of focal adhesion kinase-AKT signaling in hepatocytes. PC content was also decreased in OPN-deficient (OPN-KO) hepatocytes in which de novo FA and PC synthesis was lower, whereas cholesterol (CHOL) synthesis was higher, than in WT hepatocytes. In vivo inhibition of cholesterogenesis normalized liver PC content in OPN-KO mice, demonstrating that OPN regulates the cross-talk between liver CHOL and PC metabolism. Matched liver and serum samples showed a positive correlation between serum OPN levels and liver PC and CHOL concentration in nonobese patients with nonalcoholic fatty liver. In conclusion, OPN regulates CYP7A1 levels and the metabolic fate of liver acetyl-CoA as a result of CHOL and PC metabolism interplay. The results suggest that CYP7A1 is a main axis and that serum OPN could disrupt liver PC and CHOL metabolism, contributing to nonalcoholic fatty liver disease progression in nonobese patients.

Risk factors for metabolic syndrome after liver transplantation

DEFF Research Database (Denmark)

Thoefner, Line Buch; Rostved, Andreas Arendtsen; Pommergaard, Hans-Christian

2018-01-01

syndrome after liver transplantation. METHODS: The databases Medline and Scopus were searched for observational studies evaluating prevalence and risk factors for metabolic syndrome after liver transplantation. Meta-analyses were performed based on odds ratios (ORs) from multivariable analyses...

A proteomic-based characterization of liver metabolism in dairy cows and young pigs

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Sejersen, Henrik

This thesis deals with studies on liver metabolism in cows and pigs. Proteome analysis was used to quantify a large number of proteins involved in metabolic pathways. In cows, the objective was to characterize differences in the liver proteome between early lactation dairy cows with low or high...... liver fat content and suggest potential blood-based biomarkers for early detection of fatty liver to substantiate prevention strategies. Our results show that several proteins in liver metabolic pathways are affected by liver fat content and that blood aspartate aminotransferase, ß...

Sorafenib metabolism is significantly altered in the liver tumor tissue of hepatocellular carcinoma patient.

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Ling Ye

Full Text Available BACKGROUND: Sorafenib, the drug used as first line treatment for hepatocellular carcinoma (HCC, is metabolized by cytochrome P450 (CYP 3A4-mediated oxidation and uridine diphosphate glucuronosyl transferase (UGT 1A9-mediated glucuronidation. Liver diseases are associated with reduced CYP and UGT activities, which can considerably affect drug metabolism, leading to drug toxicity. Thus, understanding the metabolism of therapeutic compounds in patients with liver diseases is necessary. However, the metabolism characteristic of sorafenib has not been systematically determined in HCC patients. METHODS: Sorafenib metabolism was tested in the pooled and individual tumor hepatic microsomes (THLMs and adjacent normal hepatic microsomes (NHLMs of HCC patients (n = 18. Commercial hepatic microsomes (CHLMs were used as a control. In addition, CYP3A4 and UGT1A9 protein expression in different tissues were measured by Western blotting. RESULTS: The mean rates of oxidation and glucuronidation of sorafenib were significantly decreased in the pooled THLMs compared with those in NHLMs and CHLMs. The maximal velocity (Vmax of sorafenib oxidation and glucuronidation were approximately 25-fold and 2-fold decreased in the pooled THLMs, respectively, with unchanged Km values. The oxidation of sorafenib in individual THLMs sample was significantly decreased (ranging from 7 to 67-fold than that in corresponding NHLMs sample. The reduction of glucuronidation in THLMs was observed in 15 out of 18 patients' samples. Additionally, the level of CYP3A4 and UGT1A9 expression were both notably decreased in the pooled THLMs. CONCLUSIONS: Sorafenib metabolism was remarkably decreased in THLMs. This result was associated with the down regulation of the protein expression of CYP3A4 and UGT1A9.

Monkey liver cytochrome P450 2C9 is involved in caffeine 7-N-demethylation to form theophylline.

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Utoh, Masahiro; Murayama, Norie; Uno, Yasuhiro; Onose, Yui; Hosaka, Shinya; Fujino, Hideki; Shimizu, Makiko; Iwasaki, Kazuhide; Yamazaki, Hiroshi

2013-12-01

Caffeine (1,3,7-trimethylxanthine) is a phenotyping substrate for human cytochrome P450 1A2. 3-N-Demethylation of caffeine is the main human metabolic pathway, whereas monkeys extensively mediate the 7-N-demethylation of caffeine to form pharmacological active theophylline. Roles of monkey P450 enzymes in theophylline formation from caffeine were investigated using individual monkey liver microsomes and 14 recombinantly expressed monkey P450 enzymes, and the results were compared with those for human P450 enzymes. Caffeine 7-N-demethylation activity in microsomes from 20 monkey livers was not strongly inhibited by α-naphthoflavone, quinidine or ketoconazole, and was roughly correlated with diclofenac 4'-hydroxylation activities. Monkey P450 2C9 had the highest activity for caffeine 7-N-demethylation. Kinetic analysis revealed that monkey P450 2C9 had a high Vmax/Km value for caffeine 7-N-demethylation, comparable to low Km value for monkey liver microsomes. Caffeine could dock favorably with monkey P450 2C9 modeled for 7-N-demethylation and with human P450 1A2 for 3-N-demethylation. The primary metabolite theophylline was oxidized to 8-hydroxytheophylline in similar ways by liver microsomes and by recombinant P450s in both humans and monkeys. These results collectively suggest a high activity for monkey liver P450 2C9 toward caffeine 7-N-demethylation, whereas, in humans, P450 1A2-mediated caffeine 3-N-demethylation is dominant.

Alanine metabolism in pyridoxine-depleted rat liver

International Nuclear Information System (INIS)

Okada, Mitsuko; Abe, Midori

1976-01-01

Alanine metabolism in normal and pyridoxine-deficient rats was studied in vivo and in vitro. Incorporation of 14 C-alanine into various liver components was determined and no difference was shown between normal and deficient animals in the incorporation into liver homogenates, lipid, protein and plasma glucose. Using the liver slice system, gluconeogenic activity from alanine or pyruvate was 40% lower in deficient rats compared with the activity of normal rats. However, inhibition was completely removed by the addition of 2-oxoglutarate to alanine. Penicillamine did not affect glucose formation from alanine in the liver slice. (auth.)

Insulin resistance and postreceptor changes of liver metabolism in fat-fed mice

DEFF Research Database (Denmark)

Hedeskov, Carl Jørgen; Capito, Kirsten; Hansen, Svend Erik

1992-01-01

Medicinsk biokemi, animal diabetes, insulin resistance, postreceptor defects, liver metabolism, high-fat diet......Medicinsk biokemi, animal diabetes, insulin resistance, postreceptor defects, liver metabolism, high-fat diet...

Metabolism, excretion, and pharmacokinetics of S-allyl-L-cysteine in rats and dogs.

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Amano, Hirotaka; Kazamori, Daichi; Itoh, Kenji; Kodera, Yukihiro

2015-05-01

The metabolism, excretion, and pharmacokinetics of S-allyl-l-cysteine (SAC), an active key component of garlic supplements, were examined in rats and dogs. A single dose of SAC was administered orally or i.v. to rats (5 mg/kg) and dogs (2 mg/kg). SAC was well absorbed (bioavailability >90%) and its four metabolites-N-acetyl-S-allyl-l-cysteine (NAc-SAC), N-acetyl-S-allyl-l-cysteine sulfoxide (NAc-SACS), S-allyl-l-cysteine sulfoxide (SACS), and l-γ-glutamyl-S-allyl-l-cysteine-were identified in the plasma and/or urine. Renal clearance values (l/h/kg) of SAC indicated its extensive renal reabsorption, which contributed to the long elimination half-life of SAC, especially in dogs (12 hours). The metabolism of SAC to NAc-SAC, principal metabolite of SAC, was studied in vitro and in vivo. Liver and kidney S9 fractions of rats and dogs catalyzed both N-acetylation of SAC and deacetylation of NAc-SAC. After i.v. administration of NAc-SAC, SAC appeared in the plasma and its concentration declined in parallel with that of NAc-SAC. These results suggest that the rate and extent of the formation of NAc-SAC are determined by the N-acetylation and deacetylation activities of liver and kidney. Also, NAc-SACS was detected in the plasma after i.v. administration of either NAc-SAC or SACS, suggesting that NAc-SACS could be formed via both N-acetylation of SACS and S-oxidation of NAc-SAC. In conclusion, this study demonstrated that the pharmacokinetics of SAC in rats and dogs is characterized by its high oral bioavailability, N-acetylation and S-oxidation metabolism, and extensive renal reabsorption, indicating the critical roles of liver and kidney in the elimination of SAC. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Bone morphogenetic protein 9 as a key regulator of liver progenitor cells in DDC-induced cholestatic liver injury.

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Addante, Annalisa; Roncero, Cesáreo; Almalé, Laura; Lazcanoiturburu, Nerea; García-Álvaro, María; Fernández, Margarita; Sanz, Julián; Hammad, Seddik; Nwosu, Zeribe C; Lee, Se-Jin; Fabregat, Isabel; Dooley, Steven; Ten Dijke, Peter; Herrera, Blanca; Sánchez, Aránzazu

2018-05-11

Bone morphogenetic protein 9 (BMP9) interferes with liver regeneration upon acute injury, while promoting fibrosis upon carbon tetrachloride-induced chronic injury. We have now addressed the role of BMP9 in 3,5 diethoxicarbonyl-1,4 dihydrocollidine (DDC)-induced cholestatic liver injury, a model of liver regeneration mediated by hepatic progenitor cell (known as oval cell), exemplified as ductular reaction and oval cell expansion. WT and BMP9KO mice were submitted to DDC diet. Livers were examined for liver injury, fibrosis, inflammation and oval cell expansion by serum biochemistry, histology, RT-qPCR and western blot. BMP9 signalling and effects in oval cells were studied in vitro using western blot and transcriptional assays, plus functional assays of DNA synthesis, cell viability and apoptosis. Crosslinking assays and short hairpin RNA approaches were used to identify the receptors mediating BMP9 effects. Deletion of BMP9 reduces liver damage and fibrosis, but enhances inflammation upon DDC feeding. Molecularly, absence of BMP9 results in overactivation of PI3K/AKT, ERK-MAPKs and c-Met signalling pathways, which together with an enhanced ductular reaction and oval cell expansion evidence an improved regenerative response and decreased damage in response to DDC feeding. Importantly, BMP9 directly targets oval cells, it activates SMAD1,5,8, decreases cell growth and promotes apoptosis, effects that are mediated by Activin Receptor-Like Kinase 2 (ALK2) type I receptor. We identify BMP9 as a negative regulator of oval cell expansion in cholestatic injury, its deletion enhancing liver regeneration. Likewise, our work further supports BMP9 as an attractive therapeutic target for chronic liver diseases. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Methods of measuring metabolism during surgery in humans: focus on the liver-brain relationship.

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Battezzati, Alberto; Bertoli, Simona

2004-09-01

The purpose of this work is to review recent advances in setting methods and models for measuring metabolism during surgery in humans. Surgery, especially solid organ transplantation, may offer unique experimental models in which it is ethically acceptable to gain information on difficult problems of amino acid and protein metabolism. Two areas are reviewed: the metabolic study of the anhepatic phase during liver transplantation and brain microdialysis during cerebral surgery. The first model offers an innovative approach to understand the relative role of liver and extrahepatic organs in gluconeogenesis, and to evaluate whether other organs can perform functions believed to be exclusively or almost exclusively performed by the liver. The second model offers an insight to intracerebral metabolism that is closely bound to that of the liver. The recent advances in metabolic research during surgery provide knowledge immediately useful for perioperative patient management and for a better control of surgical stress. The studies during the anhepatic phase of liver transplantation have showed that gluconeogenesis and glutamine metabolism are very active processes outside the liver. One of the critical organs for extrahepatic glutamine metabolism is the brain. Microdialysis studies helped to prove that in humans there is an intense trafficking of glutamine, glutamate and alanine among neurons and astrocytes. This delicate network is influenced by systemic amino acid metabolism. The metabolic dialogue between the liver and the brain is beginning to be understood in this light in order to explain the metabolic events of brain damage during liver failure.

Influence of dietary macronutrients on liver fat accumulation and metabolism

OpenAIRE

Parry, Siôn A; Hodson, Leanne

2017-01-01

The liver is a principal metabolic organ within the human body and has a major role in regulating carbohydrate, fat, and protein metabolism. With increasing rates of obesity, the prevalence of non-alcoholic fatty liver disease (NAFLD) is growing. It remains unclear why NAFLD, which is now defined as the hepatic manifestation of the metabolic syndrome, develops but lifestyle factors such as diet (ie, total calorie and specific nutrient intakes), appear to play a key role. Here we review the av...

Skeletal Muscle Derived IL-6 in Liver and Adipose Tissue Metabolism

DEFF Research Database (Denmark)

Knudsen, Jakob Grunnet

Summary Physical activity can lead to metabolic disease and treatment of several metabolic diseases include exercise training. Skeletal muscle has, due to its central role in glucose and fat metabolism at rest and during exercise been studied in detail with regard to exercise training. The role...... of both liver and adipose tissue regulation in whole body metabolism has come in to focus and it has been shown that both tissues are subject to exercise training-induced adaptations. However, the contribution of endocrine factors to the regulation of exercise training-induced adaptations in liver...... and adipose tissue metabolism is unknown. It has been suggested that myokines, such as IL-6, released from skeletal muscle affects liver and adipose tissue and are involved in the regulation of exercise training adaptations. Thus, the aim of this thesis was to investigate the role of skeletal muscle derived...

Bone metabolism dynamics in the early post-transplant period following kidney and liver transplantation.

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Schreiber, Peter W; Bischoff-Ferrari, Heike A; Boggian, Katia; Bonani, Marco; van Delden, Christian; Enriquez, Natalia; Fehr, Thomas; Garzoni, Christian; Hirsch, Hans H; Hirzel, Cédric; Manuel, Oriol; Meylan, Pascal; Saleh, Lanja; Weisser, Maja; Mueller, Nicolas J

2018-01-01

Bone disease contributes to relevant morbidity after solid organ transplantation. Vitamin D has a crucial role for bone metabolism. Activation of vitamin D depends on the endocrine function of both, liver and kidney. Our study assessed key markers of bone metabolism at time of transplantation and 6 months after transplantation among 70 kidney and 70 liver recipients. In 70 kidney recipients 25-OH vitamin D levels did not differ significantly between peri-transplant (median 32.5nmol/l) and 6 months post-transplant (median 41.9nmol/l; P = 0.272). Six months post-transplant median 1, 25-(OH)2 vitamin D levels increased by >300% (from 9.1 to 36.5ng/l; Ptransplantation and of intact parathyroid hormone 6 months post-transplant. Among 70 liver recipients, 25-OH vitamin D, 1, 25-(OH)2 vitamin D and intact parathyroid hormone levels were not significantly altered between peri-transplant and 6 months post-transplant. Contrary to kidney recipients, median CTx increased by 60.0% (from 0.45 to 0.72 ng/ml; P = 0.002) and P1NP by 49.3% (from 84.0 to 125.4ng/ml; P = 0.001) in the longitudinal course. Assessed biomarkers didn't differ between liver recipients with and without fractures. To conclude, the assessed panel of biomarkers proved highly dynamic after liver as well as kidney transplantation in the early post-transplant period. After kidney transplantation a significant gain in 1, 25-(OH)2 vitamin D combined with a decline in iPTH, CTx and P1NP, whereas after liver transplantation an increase in CTx and P1NP were characteristic.

The Metabolism of Separase Inhibitor Sepin-1 in Human, Mouse, and Rat Liver Microsomes

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Feng Li

2018-05-01

Full Text Available Separase, a known oncogene, is widely overexpressed in numerous human tumors of breast, bone, brain, blood, and prostate. Separase is an emerging target for cancer therapy, and separase enzymatic inhibitors such as sepin-1 are currently being developed to treat separase-overexpressed tumors. Drug metabolism plays a critical role in the efficacy and safety of drug development, as well as possible drug–drug interactions. In this study, we investigated the in vitro metabolism of sepin-1 in human, mouse, and rat liver microsomes (RLM using metabolomic approaches. In human liver microsomes (HLM, we identified seven metabolites including one cysteine–sepin-1 adduct and one glutathione–sepin-1 adduct. All the sepin-1 metabolites in HLM were also found in both mouse and RLM. Using recombinant CYP450 isoenzymes, we demonstrated that multiple enzymes contributed to the metabolism of sepin-1, including CYP2D6 and CYP3A4 as the major metabolizing enzymes. Inhibitory effects of sepin-1 on seven major CYP450s were also evaluated using the corresponding substrates recommended by the US Food and Drug Administration. Our studies indicated that sepin-1 moderately inhibits CYP1A2, CYP2C19, and CYP3A4 with IC50 < 10 μM but weakly inhibits CYP2B6, CYP2C8/9, and CYP2D6 with IC50 > 10 μM. This information can be used to optimize the structures of sepin-1 for more suitable pharmacological properties and to predict the possible sepin-1 interactions with other chemotherapeutic drugs.

Circadian Reprogramming in the Liver Identifies Metabolic Pathways of Aging.

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Sato, Shogo; Solanas, Guiomar; Peixoto, Francisca Oliveira; Bee, Leonardo; Symeonidi, Aikaterini; Schmidt, Mark S; Brenner, Charles; Masri, Selma; Benitah, Salvador Aznar; Sassone-Corsi, Paolo

2017-08-10

The process of aging and circadian rhythms are intimately intertwined, but how peripheral clocks involved in metabolic homeostasis contribute to aging remains unknown. Importantly, caloric restriction (CR) extends lifespan in several organisms and rewires circadian metabolism. Using young versus old mice, fed ad libitum or under CR, we reveal reprogramming of the circadian transcriptome in the liver. These age-dependent changes occur in a highly tissue-specific manner, as demonstrated by comparing circadian gene expression in the liver versus epidermal and skeletal muscle stem cells. Moreover, de novo oscillating genes under CR show an enrichment in SIRT1 targets in the liver. This is accompanied by distinct circadian hepatic signatures in NAD + -related metabolites and cyclic global protein acetylation. Strikingly, this oscillation in acetylation is absent in old mice while CR robustly rescues global protein acetylation. Our findings indicate that the clock operates at the crossroad between protein acetylation, liver metabolism, and aging. Copyright © 2017 Elsevier Inc. All rights reserved.

Studies of liver-specific metabolic reactions with /sup 15/N. 1. Metabolism of /sup 15/N-ammonium chloride in pigs

Energy Technology Data Exchange (ETDEWEB)

Hirschberg, K; Jung, K; Faust, H; Matkowitz, R

1987-07-01

The /sup 15/N tracer technique was used to investigate liver-specific reactions (urea and hippurate synthesis) for studying the metabolism in the healthy and damaged pig liver. After (/sup 15/N)ammonium chloride administration the tracer distribution on non-protein compounds of serum and urine was followed. Blood samplings before and after liver passage rendered possible a direct analysis of the (/sup 15/N)ammonium metabolism. The thioacetamide-induced liver damage was used as model for an acute liver intoxication. The capacity for urea synthesis was not influenced by means of this noxious substance, but the metabolism of amino acids and hippuric acid. The considerably depressed excretion of (/sup 15/N)hippurate seems to be a suitable indicator of liver disfunction.

Cholesteryl ester transfer protein alters liver and plasma triglyceride metabolism through two liver networks in female mice.

Science.gov (United States)

Palmisano, Brian T; Le, Thao D; Zhu, Lin; Lee, Yoon Kwang; Stafford, John M

2016-08-01

Elevated plasma TGs increase risk of cardiovascular disease in women. Estrogen treatment raises plasma TGs in women, but molecular mechanisms remain poorly understood. Here we explore the role of cholesteryl ester transfer protein (CETP) in the regulation of TG metabolism in female mice, which naturally lack CETP. In transgenic CETP females, acute estrogen treatment raised plasma TGs 50%, increased TG production, and increased expression of genes involved in VLDL synthesis, but not in nontransgenic littermate females. In CETP females, estrogen enhanced expression of small heterodimer partner (SHP), a nuclear receptor regulating VLDL production. Deletion of liver SHP prevented increases in TG production and expression of genes involved in VLDL synthesis in CETP mice with estrogen treatment. We also examined whether CETP expression had effects on TG metabolism independent of estrogen treatment. CETP increased liver β-oxidation and reduced liver TG content by 60%. Liver estrogen receptor α (ERα) was required for CETP expression to enhance β-oxidation and reduce liver TG content. Thus, CETP alters at least two networks governing TG metabolism, one involving SHP to increase VLDL-TG production in response to estrogen, and another involving ERα to enhance β-oxidation and lower liver TG content. These findings demonstrate a novel role for CETP in estrogen-mediated increases in TG production and a broader role for CETP in TG metabolism. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.

Alginate Immobilization of Metabolic Enzymes (AIME) for High ...

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Alginate Immobilization of Metabolic Enzymes (AIME) for High-Throughput Screening Assays DE DeGroot, RS Thomas, and SO SimmonsNational Center for Computational Toxicology, US EPA, Research Triangle Park, NC USAThe EPA’s ToxCast program utilizes a wide variety of high-throughput screening (HTS) assays to assess chemical perturbations of molecular and cellular endpoints. A key criticism of using HTS assays for toxicity assessment is the lack of xenobiotic metabolism (XM) which precludes both metabolic detoxification as well as bioactivation of chemicals tested in vitro thereby mischaracterizing the potential risk posed by these chemicals. To address this deficiency, we have developed an extracellular platform to retrofit existing HTS assays with XM activity. This platform utilizes the S9 fraction of liver homogenate encapsulated in an alginate gel network which reduces the cytotoxicity caused by direct addition of S9 to cells in culture. Alginate microspheres containing encapsulated human liver S9 were cross-linked to solid supports extending from a 96-well plate lid and were assayed using a pro-luciferin substrate specific for CYP3A4 (IPA). We demonstrate that S9 was successfully encapsulated and remained enzymatically active post-encapsulation with 5-10X the CYP3A4 activity as compared to 1 µg solubilized human liver S9. Ketoconazole, a known inhibitor of human CYP3A4, inhibited CYP3A4 activity in a concentration-dependent manner (IC50: 0.27 µM) and inhibiti

In Vivo Acute on Chronic Ethanol Effects in Liver: A Mouse Model Exhibiting Exacerbated Injury, Altered Metabolic and Epigenetic Responses

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Shivendra D. Shukla

2015-11-01

Full Text Available Chronic alcoholics who also binge drink (i.e., acute on chronic are prone to an exacerbated liver injury but its mechanism is not understood. We therefore investigated the in vivo effects of chronic and binge ethanol ingestion and compared to chronic ethanol followed by three repeat binge ethanol on the liver of male C57/BL6 mice fed ethanol in liquid diet (4% for four weeks followed by binge ethanol (intragastric administration, 3.5 g/kg body weight, three doses, 12h apart. Chronic followed by binge ethanol exacerbated fat accumulation, necrosis, decrease in hepatic SAM and SAM:SAH ratio, increase in adenosine levels, and elevated CYP2E1 levels. Histone H3 lysine acetylation (H3AcK9, dually modified phosphoacetylated histone H3 (H3AcK9/PS10, and phosphorylated H2AX increased after binge whereas phosphorylation of histone H3 ser 10 (H3S10 and H3 ser 28 (H3S28 increased after chronic ethanol-binge. Histone H3 lysine 4 and 9 dimethylation increased with a marked dimethylation in H3K9 in chronic ethanol binge group. Trimethylated histone H3 levels did not change. Nuclear levels of histone acetyl transferase GCN5 and histone deacetylase HDAC3 were elevated whereas phospho-CREB decreased in a distinctive manner. Taken together, acute on chronic ethanol ingestion caused amplification of liver injury and elicited characteristic profiles of histone modifications, metabolic alterations, and changes in nuclear protein levels. These findings demonstrate that chronic ethanol exposure renders liver more susceptible to repeat acute/binge ethanol induced acceleration of alcoholic liver disease.

Metabolic Disturbances in Children with Chronic Liver Disease

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A Rezaeian

2014-04-01

Full Text Available Introduction: Liver disease results in complex pathophysiologic disturbances affecting nutrient digestion, absorption, distribution, storage, and use. This article aimed to present a classification of metabolic disturbances in chronic liver disease in children?   Materials and Methods: In this review study databases including proquest, pubmedcentral, scincedirect, ovid, medlineplus were been searched with keyword words such as” chronic liver disease"  ” metabolic disorder””children” between 1999 to 2014. Finally, 8 related articles have been found.   Results: Metabolic disorder in this population could be categorized in four set: 1carbohydrates, 2proteins,3 fats and 4vitamins. 1 Carbohydrates: Children with CLD are at increased risk for fasting hypoglycemia, because the capacity for glycogen storage and gluconeogenesis is reduced as a result of abnormal hepatocyte function and loss of hepatocyte mass. 2 Proteins: The liver’s capacity for plasma protein synthesis is impaired by reduced substrate availability, impaired hepatocyte function, and increased catabolism. This results in hypoalbuminemia, leading to peripheral edema and contributing to ascites. Reduced synthesis of insulin-like growth factor (IGF-1 and its binding protein IGF-BP3 by the chronically diseased liver results in growth hormone resistance and may contribute to the poor growth observed in these children. 3 Fats: There is increased fat oxidation in children with end-stage liver disease in the fed and fasting states compared with controls, which is probably related to reduced carbohydrate availability. The increased lipolysis results in a decrease in fat stores, which may not be easily replenished in the setting of the fat malabsorption that accompanies cholestasis. Reduced bile delivery to the gut results in impaired fat emulsification, and hence digestion. The products of fat digestion are also poorly absorbed, because bile is also required for micelle formation

Inherited metabolic liver diseases in infants and children: an overview

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Ivo Barić

2013-10-01

Full Text Available Inborn errors of metabolism, which affect the liver are a large, continuously increasing group of diseases. Their clinical onset can occur at any age, from intrauterine period presenting as liver failure already at birth to late adulthood. Inherited metabolic disorders must be considered in differential diagnosis of every unexplained liver disease. Specific diagnostic work-up for either their confirmation or exclusion should start immediately since any postponing can result in delayed diagnosis and death or irreversible disability. This can be particularly painful while many inherited metabolic liver diseases are relatively easily treatable if diagnosed on time, for instance galactosemia or hereditary fructose intolerance by simple dietary means. Any unexplained liver disease, even one looking initially benign, should be considered as a potential liver failure and therefore should deserve proper attention. Diagnosis in neonates is additionally complicated because of the factors which can mask liver disease, such as physiological neonatal jaundice, normally relatively enlarged liver and increased transaminases at that age. In everyday practice, in order to reveal the etiology, it is useful to classify and distinguish some clinical patterns which, together with a few routine, widely available laboratory tests (aminotransferases, prothrombine time, albumin, gammaGT, total and conjugated bilirubin, ammonia, alkaline phosphatase and glucose make the search for the cause much easier. These patterns are isolated hyperbilirubinemia, syndrome of cholestasis in early infancy, hepatocellular jaundice, Reye syndrome, portal cirrhosis and isolated hepatomegaly. Despite the fact that some diseases can present with more than one pattern (for instance, alpha-1-antitrypsin deficiency as infantile cholestasis, but also as hepatocellular jaundice, and that in some disesases one pattern can evolve into another (for instance, Wilson disease from hepatocellular

Influence of dietary macronutrients on liver fat accumulation and metabolism

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Parry, Siôn A; Hodson, Leanne

2017-01-01

The liver is a principal metabolic organ within the human body and has a major role in regulating carbohydrate, fat, and protein metabolism. With increasing rates of obesity, the prevalence of non-alcoholic fatty liver disease (NAFLD) is growing. It remains unclear why NAFLD, which is now defined as the hepatic manifestation of the metabolic syndrome, develops but lifestyle factors such as diet (ie, total calorie and specific nutrient intakes), appear to play a key role. Here we review the available observational and intervention studies that have investigated the influence of dietary macronutrients on liver fat content. Findings from observational studies are conflicting with some reporting that relative to healthy controls, patients with NAFLD consume diets higher in total fat/saturated fatty acids, whilst others find they consume diets higher in carbohydrates/sugars. From the limited number of intervention studies that have been undertaken, a consistent finding is a hypercaloric diet, regardless of whether the excess calories have been provided either as fat, sugar, or both, increases liver fat content. In contrast, a hypocaloric diet decreases liver fat content. Findings from both hyper- and hypo-caloric feeding studies provide some suggestion that macronutrient composition may also play a role in regulating liver fat content and this is supported by data from isocaloric feeding studies; fatty acid composition and/or carbohydrate content/type appear to influence whether there is accrual of liver fat or not. The mechanisms by which specific macronutrients, when consumed as part of an isocaloric diet, cause a change in liver fat remain to be fully elucidated. PMID:28947639

Novel metabolic pathways for linoleic and arachidonic acid metabolism.

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Moghaddam, M; Motoba, K; Borhan, B; Pinot, F; Hammock, B D

1996-08-13

Mouse liver microsomes oxidized linoleic acid to form 9,10- or 12,13-epoxyoctadecenoate. These monoepoxides were subsequently hydrolyzed to their corresponding diols in the absence of the microsomal epoxide hydrolase inhibitor, 1,2-epoxy-3,3,3-trichloropropane. Furthermore, both 9,10- and 12,13-epoxyoctadecenoates were oxidized to diepoxyoctadecanoate at apparently identical rates by mouse liver microsomal P-450 epoxidation. Both epoxyoctadecanoates and diepoxyoctadecanoates were converted to tetrahydrofuran-diols by microsomes. Tetrahydroxides of linoleate were produced as minor metabolites. Arachidonic acid was metabolized to epoxyeicosatrienoates, dihydroxyeicosatrienoates, and monohydroxyeicosatetraenoates by the microsomes. Microsomes prepared from clofibrate (but not phenobarbital) -treated mice exhibited much higher production rates for epoxyeicosatrienoates and vic-dihydroxyeicosatrienoates. This indicated an induction of P-450 epoxygenase(s) and microsomal epoxide hydrolase in mice by clofibrate and not by phenobarbital. Incubation of synthetic epoxyeicosatrienoates with microsomes led to the production of diepoxyeicosadienoates. Among chemically generated diepoxyeicosadienoate isomers, three of them possessing adjacent diepoxides were hydrolyzed to their diol epoxides which cyclized to the corresponding tetrahydrofuran-diols by microsomes as well as soluble epoxide hydrolase at a much higher rate. Larger cyclic products from non-adjacent diepoxides were not observed. The results of our in vitro experiments suggest that linoleic and arachidonic acid can be metabolized to their tetrahydrofuran-diols by two consecutive microsomal cytochrome P-450 epoxidations followed by microsomal or soluble epoxide hydrolase catalyzed hydrolysis of the epoxides. Incubation experiments with the S-9 fractions indicate that the soluble epoxide hydrolase is more important in this conversion. This manuscript is the first report of techniques for the separation and

Coordinated and interactive expression of genes of lipid metabolism and inflammation in adipose tissue and liver during metabolic overload.

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Wen Liang

Full Text Available BACKGROUND: Chronic metabolic overload results in lipid accumulation and subsequent inflammation in white adipose tissue (WAT, often accompanied by non-alcoholic fatty liver disease (NAFLD. In response to metabolic overload, the expression of genes involved in lipid metabolism and inflammatory processes is adapted. However, it still remains unknown how these adaptations in gene expression in expanding WAT and liver are orchestrated and whether they are interrelated. METHODOLOGY/PRINCIPAL FINDINGS: ApoE*3Leiden mice were fed HFD or chow for different periods up to 12 weeks. Gene expression in WAT and liver over time was evaluated by micro-array analysis. WAT hypertrophy and inflammation were analyzed histologically. Bayesian hierarchical cluster analysis of dynamic WAT gene expression identified groups of genes ('clusters' with comparable expression patterns over time. HFD evoked an immediate response of five clusters of 'lipid metabolism' genes in WAT, which did not further change thereafter. At a later time point (>6 weeks, inflammatory clusters were induced. Promoter analysis of clustered genes resulted in specific key regulators which may orchestrate the metabolic and inflammatory responses in WAT. Some master regulators played a dual role in control of metabolism and inflammation. When WAT inflammation developed (>6 weeks, genes of lipid metabolism and inflammation were also affected in corresponding livers. These hepatic gene expression changes and the underlying transcriptional responses in particular, were remarkably similar to those detected in WAT. CONCLUSION: In WAT, metabolic overload induced an immediate, stable response on clusters of lipid metabolism genes and induced inflammatory genes later in time. Both processes may be controlled and interlinked by specific transcriptional regulators. When WAT inflammation began, the hepatic response to HFD resembled that in WAT. In all, WAT and liver respond to metabolic overload by

Metabolism, genomics, and DNA repair in the mouse aging liver

DEFF Research Database (Denmark)

Lebel, Michel; de Souza-Pinto, Nadja C; Bohr, Vilhelm A

2011-01-01

hepatic metabolic and detoxification activities, with implications for systemic aging and age-related disease. It has become clear, using rodent models as biological tools, that genetic instability in the form of gross DNA rearrangements or point mutations accumulate in the liver with age. DNA lesions......The liver plays a pivotal role in the metabolism of nutrients, drugs, hormones, and metabolic waste products, thereby maintaining body homeostasis. The liver undergoes substantial changes in structure and function within old age. Such changes are associated with significant impairment of many......, such as oxidized bases or persistent breaks, increase with age and correlate well with the presence of senescent hepatocytes. The level of DNA damage and/or mutation can be affected by changes in carcinogen activation, decreased ability to repair DNA, or a combination of these factors. This paper covers some...

Metabolic adaptations in models of fatty liver disease : Of mice and math

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Hijmans, Brenda

2017-01-01

The increasing incidence of overweight is accompanied by a plethora of medical symptoms together called the metabolic syndrome. Non-alcoholic fatty liver disease, characterized by persistent storage of lipids in the liver, is regarded as the hepatic component of the metabolic syndrome. An imbalance

Sex-specific metabolic interactions between liver and adipose tissue in MCD diet-induced non-alcoholic fatty liver disease.

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Lee, Yun-Hee; Kim, Sou Hyun; Kim, Sang-Nam; Kwon, Hyun-Jung; Kim, Jeong-Dong; Oh, Ji Youn; Jung, Young-Suk

2016-07-26

Higher susceptibility to metabolic disease in male exemplifies the importance of sexual dimorphism in pathogenesis. We hypothesized that the higher incidence of non-alcoholic fatty liver disease in males involves sex-specific metabolic interactions between liver and adipose tissue. In the present study, we used a methionine-choline deficient (MCD) diet-induced fatty liver mouse model to investigate sex differences in the metabolic response of the liver and adipose tissue. After 2 weeks on an MCD-diet, fatty liver was induced in a sex-specific manner, affecting male mice more severely than females. The MCD-diet increased lipolytic enzymes in the gonadal white adipose tissue (gWAT) of male mice, whereas it increased expression of uncoupling protein 1 and other brown adipocyte markers in the gWAT of female mice. Moreover, gWAT from female mice demonstrated higher levels of oxygen consumption and mitochondrial content compared to gWAT from male mice. FGF21 expression was increased in liver tissue by the MCD diet, and the degree of upregulation was significantly higher in the livers of female mice. The endocrine effect of FGF21 was responsible, in part, for the sex-specific browning of gonadal white adipose tissue. Collectively, these data demonstrated that distinctively female-specific browning of white adipose tissue aids in protecting female mice against MCD diet-induced fatty liver disease.

Liver Inflammation and Metabolic Signaling in ApcMin/+ Mice: The Role of Cachexia Progression

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Narsale, Aditi A.; Enos, Reilly T.; Puppa, Melissa J.; Chatterjee, Saurabh; Murphy, E. Angela; Fayad, Raja; Pena, Majorette O’; Durstine, J. Larry; Carson, James A.

2015-01-01

The ApcMin/+ mouse exhibits an intestinal tumor associated loss of muscle and fat that is accompanied by chronic inflammation, insulin resistance and hyperlipidemia. Since the liver governs systemic energy demands through regulation of glucose and lipid metabolism, it is likely that the liver is a pathological target of cachexia progression in the ApcMin/+ mouse. The purpose of this study was to determine if cancer and the progression of cachexia affected liver endoplasmic reticulum (ER)-stress, inflammation, metabolism, and protein synthesis signaling. The effect of cancer (without cachexia) was examined in wild-type and weight-stable ApcMin/+ mice. Cachexia progression was examined in weight-stable, pre-cachectic, and severely-cachectic ApcMin/+ mice. Livers were analyzed for morphology, glycogen content, ER-stress, inflammation, and metabolic changes. Cancer induced hepatic expression of ER-stress markers BiP (binding immunoglobulin protein), IRE-1α (endoplasmic reticulum to nucleus signaling 1), and inflammatory intermediate STAT-3 (signal transducer and activator of transcription 3). While gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK) mRNA expression was suppressed by cancer, glycogen content or protein synthesis signaling remained unaffected. Cachexia progression depleted liver glycogen content and increased mRNA expression of glycolytic enzyme PFK (phosphofrucktokinase) and gluconeogenic enzyme PEPCK. Cachexia progression further increased pSTAT-3 but suppressed p-65 and JNK (c-Jun NH2-terminal kinase) activation. Interestingly, progression of cachexia suppressed upstream ER-stress markers BiP and IRE-1α, while inducing its downstream target CHOP (DNA-damage inducible transcript 3). Cachectic mice exhibited a dysregulation of protein synthesis signaling, with an induction of p-mTOR (mechanistic target of rapamycin), despite a suppression of Akt (thymoma viral proto-oncogene 1) and S6 (ribosomal protein S6) phosphorylation. Thus, cancer

Liver inflammation and metabolic signaling in ApcMin/+ mice: the role of cachexia progression.

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Aditi A Narsale

Full Text Available The ApcMin/+ mouse exhibits an intestinal tumor associated loss of muscle and fat that is accompanied by chronic inflammation, insulin resistance and hyperlipidemia. Since the liver governs systemic energy demands through regulation of glucose and lipid metabolism, it is likely that the liver is a pathological target of cachexia progression in the ApcMin/+ mouse. The purpose of this study was to determine if cancer and the progression of cachexia affected liver endoplasmic reticulum (ER-stress, inflammation, metabolism, and protein synthesis signaling. The effect of cancer (without cachexia was examined in wild-type and weight-stable ApcMin/+ mice. Cachexia progression was examined in weight-stable, pre-cachectic, and severely-cachectic ApcMin/+ mice. Livers were analyzed for morphology, glycogen content, ER-stress, inflammation, and metabolic changes. Cancer induced hepatic expression of ER-stress markers BiP (binding immunoglobulin protein, IRE-1α (endoplasmic reticulum to nucleus signaling 1, and inflammatory intermediate STAT-3 (signal transducer and activator of transcription 3. While gluconeogenic enzyme phosphoenolpyruvate carboxykinase (PEPCK mRNA expression was suppressed by cancer, glycogen content or protein synthesis signaling remained unaffected. Cachexia progression depleted liver glycogen content and increased mRNA expression of glycolytic enzyme PFK (phosphofrucktokinase and gluconeogenic enzyme PEPCK. Cachexia progression further increased pSTAT-3 but suppressed p-65 and JNK (c-Jun NH2-terminal kinase activation. Interestingly, progression of cachexia suppressed upstream ER-stress markers BiP and IRE-1α, while inducing its downstream target CHOP (DNA-damage inducible transcript 3. Cachectic mice exhibited a dysregulation of protein synthesis signaling, with an induction of p-mTOR (mechanistic target of rapamycin, despite a suppression of Akt (thymoma viral proto-oncogene 1 and S6 (ribosomal protein S6 phosphorylation. Thus

Comparison of trout hepatocytes and liver S9 fractions as in vitro models for predicting hepatic clearance in fish

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Isolated hepatocytes and liver S9 fractions have been used to collect in vitro biotransformation data for fish as a means of improving modeled estimates of chemical bioaccumulation. To date, however, there have been few direct comparisons of these two methods. In the present st...

Fatty liver as a risk factor for progression from metabolically healthy to metabolically abnormal in non-overweight individuals.

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Hashimoto, Yoshitaka; Hamaguchi, Masahide; Fukuda, Takuya; Ohbora, Akihiro; Kojima, Takao; Fukui, Michiaki

2017-07-01

Recent studies identified that metabolically abnormal non-obese phenotype is a risk factor for cardiovascular diseases. However, little is known about risk factor for progression from metabolically healthy non-overweight to metabolically abnormal phenotype. We hypothesized that fatty liver had a clinical impact on progression from metabolically healthy non-overweight to metabolically abnormal phenotype. In this retrospective cohort study, 14,093 Japanese (7557 men and 6736 women), who received the health-checkup program from 2004 to 2012, were enrolled. Overweight and obesity were defined as body mass index 23.0-25.0 and ≥25.0 kg/m 2 . Four metabolic factors (impaired fasting glucose, hypertension, hypertriglyceridemia and low high density lipoprotein-cholesterol concentration) were used for definition of metabolically healthy (less than two factors) or metabolically abnormal (two or more). We divided the participants into three groups: metabolically healthy non-overweight (9755 individuals, men/women = 4290/5465), metabolically healthy overweight (2547 individuals, 1800/747) and metabolically healthy obesity (1791 individuals, 1267/524). Fatty liver was diagnosed by ultrasonography. Over the median follow-up period of 5.3 years, 873 metabolically healthy non-overweight, 512 metabolically healthy overweight and 536 metabolically healthy obesity individuals progressed to metabolically abnormal. The adjusted hazard risks of fatty liver on progression were 1.49 (95% confidence interval 1.20-1.83, p = 0.005) in metabolically healthy non-overweight, 1.37 (1.12-1.66, p = 0.002) in metabolically healthy overweight and 1.38 (1.15-1.66, p overweight individuals.

The association between donor genetic variations in one-carbon metabolism pathway genes and hepatitis B recurrence after liver transplantation.

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Lu, Di; Zhuo, Jianyong; Yang, Modan; Wang, Chao; Linhui, Pan; Xie, Haiyang; Xu, Xiao; Zheng, Shusen

2018-04-05

Hepatitis B recurrence adversely affects patients' survival after liver transplantation. This study aims to find association between donor gene variations of one carbon metabolism and post-transplant hepatitis B recurrence. This study enrolled 196 patients undergoing liver transplantation for HBV related end-stage liver diseases. We detected 11 single nucleotide polymorphisms (SNP) of 7 one-carbon metabolism pathway genes (including MTHFR, MTR, MTRR, ALDH1L1, GART, SHMT1 and CBS) in donor livers and analyzed their association with HBV reinfection after liver transplantation. Hepatitis B recurrence was observed in 19 of the 196 patients (9.7%) undergoing liver transplantation. Hepatitis B recurrence significantly affected post-transplant survival in the 196 patients (p = 0.018), and correlate with tumor recurrence in the subgroup of HCC patients (n = 99, p = 0.006). Among the 11 SNPs, donor liver mutation in rs1979277 (G > A) was adversely associated with post-transplant hepatitis B recurrence (p = 0.042). In the subgroup of HCC patients, survival analysis showed donor liver mutations in rs1801133 (G > A) and rs1979277 (G > A) were risk factors for hepatitis B recurrence (p B recurrence in non-HCC patients (n = 97, p > 0.05). Hepatitis B recurrence impaired post-transplant survival. Donor liver genetic variations in one-carbon metabolism pathway genes were significantly associated with post-transplant hepatitis B recurrence. Copyright © 2017. Published by Elsevier B.V.

New psychoactive substances: Studies on the metabolism of XLR-11, AB-PINACA, FUB-PB-22, 4-methoxy-α-PVP, 25-I-NBOMe, and meclonazepam using human liver preparations in comparison to primary human hepatocytes, and human urine.

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Richter, Lilian H J; Maurer, Hans H; Meyer, Markus R

2017-10-05

New psychoactive substances (NPS) are an increasing problem in clinical and forensic toxicology. The knowledge of their metabolism is important for toxicological risk assessment and for developing toxicological urine screenings. Considering the huge numbers of NPS annually appearing on the market, metabolism studies should be realized in a fast, simple, cost efficient, and reliable way. Primary human hepatocytes (PHH) were recommended to be the gold standard for in vitro metabolism studies as they are expected to contain natural enzyme clusters, co-substrates, and drug transporters. In addition, they were already successfully used for metabolism studies of NPS. However, they also have disadvantages such as high costs and limited applicability without special equipment. The aims of the present study were therefore first to investigate exemplarily the phase I and phase II metabolism of six NPS (XLR-11, AB-PINACA, FUB-PB-22, 4-methoxy-α-PVP, 25-I-NBOMe, and meclonazepam) from different drug classes using pooled human S9 fraction (pS9) or pooled human liver microsomes combined with cytosol (pHLM/pHLC) after addition of the co-substrates for the main metabolic phase I and II reactions. Second to compare results to published data generated using primary human hepatocytes and human urine samples. Results of the incubations with pS9 or pHLM/pHLC were comparable in number and abundance of metabolites. Formation of metabolites, particularly after multi-step reactions needed a longer incubation time. However, incubations using human liver preparations resulted in a lower number of total detected metabolites compared to PHH, but they were still able to allow the identification of the main human urinary excretion products. Human liver preparations and particularly the pooled S9 fraction could be shown to be a sufficient and more cost-efficient alternative in context of metabolism studies also for developing toxicological urine screenings. It might be recommended to use the

Nor-Ursodeoxycholic Acid as a Novel Therapeutic Approach for Cholestatic and Metabolic Liver Diseases.

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Halilbasic, Emina; Steinacher, Daniel; Trauner, Michael

2017-01-01

Norursodeoxycholic acid (norUDCA) is a side-chain-shortened derivative of ursodeoxycholic acid with relative resistance to amidation, which enables its cholehepatic shunting. Based on its specific pharmacologic properties, norUDCA is a promising drug for a range of cholestatic liver and bile duct disorders. Recently, norUDCA has been successfully tested clinically in patients with primary sclerosing cholangitis (PSC) as first application in patients. Moreover, hepatic enrichment of norUDCA facilitates direct therapeutic effects on both parenchymal and non-parenchymal liver cells, thereby counteracting cholestasis, steatosis, hepatic inflammation and fibrosis, inhibiting hepatocellular proliferation, and promoting autophagy. This may open its therapeutic use to other non-cholestatic and metabolic liver diseases. This review article is a summary of a lecture given at the XXIV International Bile Acid Meeting (Falk Symposium 203) on "Bile Acids in Health and Disease" held in Düsseldorf, on June 17-18, 2016 and summarizes the recent progress of norUDCA as novel therapeutic approach in cholestatic and metabolic liver disorders with a specific focus on PSC. © 2017 S. Karger AG, Basel.

The effectiveness of metformin in patients with metabolic syndrome and nonalcoholic fatty liver disease

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S A Butrova

2008-06-01

Full Text Available The mechanism of action of metformin is realized through activation of cAMP-dependent protein kinase, leading to a decrease hepatic glucose production as well as to decrease the synthesis of triglycerides and an increase in fat oxidation. Several studies have demonstrated the positive effect of the drug in non-alcoholic fatty liver disease, manifested in reducing the activity of enzymes, reducing the size of the liver and insulin resistance. The aim of our study was to evaluate the effectiveness of metformin in patients with metabolic syndrome and nonalcoholic fatty liver disease. The study found that the use Siofor 850 mg 2 times a day in conjunction with a reduced-calorie nutrition in patients with metabolic syndrome and nonalcoholic fatty liver disease leads to a significant reduction in insulin resistance associated with decreased activity of transaminases, improvement of metabolic parameters. The therapy Siofor majority of patients (60% with metabolic syndrome and nonalcoholic fatty liver disease achieved a clinically significant weight loss and improved body composition. Application Siofor improves lifestyle changes in obese patients with non-alcoholic liver disease dirovoy and metabolic disorders.

Diet and liver apoptosis in rats: a particular metabolic pathway.

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Monteiro, Maria Emilia Lopes; Xavier, Analucia Rampazzo; Azeredo, Vilma Blondet

2017-03-30

Various studies have indicated an association between modifi cation in dietary macronutrient composition and liver apoptosis. To explain how changes in metabolic pathways associated with a high-protein, high-fat, and low-carbohydrate diet causes liver apoptosis. Two groups of rats were compared. An experimental diet group (n = 8) using a high-protein (59.46%), high-fat (31.77%), and low-carbohydrate (8.77%) diet versus a control one (n = 9) with American Institute of Nutrition (AIN)-93-M diet. Animals were sacrificed after eight weeks, the adipose tissue weighed, the liver removed for flow cytometry analysis, and blood collected to measure glucose, insulin, glucagon, IL-6, TNF, triglycerides, malondialdehyde, and β-hydroxybutyrate. Statistical analysis was carried out using the unpaired and parametric Student's t-test and Pearson's correlation coeffi ents. Significance was set at p triglycerides lower levels compared with the control group. The results show a positive and significant correlation between the percentage of nonviable hepatocytes and malondialdehyde levels (p = 0.0217) and a statistically significant negative correlation with triglycerides levels (p = 0.006). Results suggest that plasmatic malondialdehyde and triglyceride levels are probably good predictors of liver damage associated with an experimental low-carbohydrate diet in rats.

Influence of dietary macronutrients on liver fat accumulation and metabolism.

Science.gov (United States)

Parry, Siôn A; Hodson, Leanne

2017-12-01

The liver is a principal metabolic organ within the human body and has a major role in regulating carbohydrate, fat, and protein metabolism. With increasing rates of obesity, the prevalence of non-alcoholic fatty liver disease (NAFLD) is growing. It remains unclear why NAFLD, which is now defined as the hepatic manifestation of the metabolic syndrome, develops but lifestyle factors such as diet (ie, total calorie and specific nutrient intakes), appear to play a key role. Here we review the available observational and intervention studies that have investigated the influence of dietary macronutrients on liver fat content. Findings from observational studies are conflicting with some reporting that relative to healthy controls, patients with NAFLD consume diets higher in total fat/saturated fatty acids, whilst others find they consume diets higher in carbohydrates/sugars. From the limited number of intervention studies that have been undertaken, a consistent finding is a hypercaloric diet, regardless of whether the excess calories have been provided either as fat, sugar, or both, increases liver fat content. In contrast, a hypocaloric diet decreases liver fat content. Findings from both hyper- and hypo-caloric feeding studies provide some suggestion that macronutrient composition may also play a role in regulating liver fat content and this is supported by data from isocaloric feeding studies; fatty acid composition and/or carbohydrate content/type appear to influence whether there is accrual of liver fat or not. The mechanisms by which specific macronutrients, when consumed as part of an isocaloric diet, cause a change in liver fat remain to be fully elucidated. © American Federation for Medical Research (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Diet-induced metabolic hamster model of nonalcoholic fatty liver disease

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Bhathena J

2011-06-01

Full Text Available Jasmine Bhathena, Arun Kulamarva, Christopher Martoni, Aleksandra Malgorzata Urbanska, Meenakshi Malhotra, Arghya Paul, Satya PrakashBiomedical Technology and Cell Therapy Research Laboratory, Department of Biomedical Engineering, Artificial Cells and Organs Research Centre, Faculty of Medicine, McGill University, Montreal, Québec, CanadaBackground: Obesity, hypercholesterolemia, elevated triglycerides, and type 2 diabetes are major risk factors for metabolic syndrome. Hamsters, unlike rats or mice, respond well to diet-induced obesity, increase body mass and adiposity on group housing, and increase food intake due to social confrontation-induced stress. They have a cardiovascular and hepatic system similar to that of humans, and can thus be a useful model for human pathophysiology.Methods: Experiments were planned to develop a diet-induced Bio F1B Golden Syrian hamster model of dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hamsters were fed a normal control diet, a high-fat/high-cholesterol diet, a high-fat/high-cholesterol/methionine-deficient/choline-devoid diet, and a high-fat/high-cholesterol/choline-deficient diet. Serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, glucose, atherogenic index, and body weight were quantified biweekly. Fat deposition in the liver was observed and assessed following lipid staining with hematoxylin and eosin and with oil red O.Results: In this study, we established a diet-induced Bio F1B Golden Syrian hamster model for studying dyslipidemia and associated nonalcoholic fatty liver disease in the metabolic syndrome. Hyperlipidemia and elevated serum glucose concentrations were induced using this diet. Atherogenic index was elevated, increasing the risk for a cardiovascular event. Histological analysis of liver specimens at the end of four weeks showed increased fat deposition in the liver of animals fed

Fasting-induced liver GADD45β restrains hepatic fatty acid uptake and improves metabolic health.

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Fuhrmeister, Jessica; Zota, Annika; Sijmonsma, Tjeerd P; Seibert, Oksana; Cıngır, Şahika; Schmidt, Kathrin; Vallon, Nicola; de Guia, Roldan M; Niopek, Katharina; Berriel Diaz, Mauricio; Maida, Adriano; Blüher, Matthias; Okun, Jürgen G; Herzig, Stephan; Rose, Adam J

2016-06-01

Recent studies have demonstrated that repeated short-term nutrient withdrawal (i.e. fasting) has pleiotropic actions to promote organismal health and longevity. Despite this, the molecular physiological mechanisms by which fasting is protective against metabolic disease are largely unknown. Here, we show that, metabolic control, particularly systemic and liver lipid metabolism, is aberrantly regulated in the fasted state in mouse models of metabolic dysfunction. Liver transcript assays between lean/healthy and obese/diabetic mice in fasted and fed states uncovered "growth arrest and DNA damage-inducible" GADD45β as a dysregulated gene transcript during fasting in several models of metabolic dysfunction including ageing, obesity/pre-diabetes and type 2 diabetes, in both mice and humans. Using whole-body knockout mice as well as liver/hepatocyte-specific gain- and loss-of-function strategies, we revealed a role for liver GADD45β in the coordination of liver fatty acid uptake, through cytoplasmic retention of FABP1, ultimately impacting obesity-driven hyperglycaemia. In summary, fasting stress-induced GADD45β represents a liver-specific molecular event promoting adaptive metabolic function. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

Detection of driver metabolites in the human liver metabolic network using structural controllability analysis

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2014-01-01

Background Abnormal states in human liver metabolism are major causes of human liver diseases ranging from hepatitis to hepatic tumor. The accumulation in relevant data makes it feasible to derive a large-scale human liver metabolic network (HLMN) and to discover important biological principles or drug-targets based on network analysis. Some studies have shown that interesting biological phenomenon and drug-targets could be discovered by applying structural controllability analysis (which is a newly prevailed concept in networks) to biological networks. The exploration on the connections between structural controllability theory and the HLMN could be used to uncover valuable information on the human liver metabolism from a fresh perspective. Results We applied structural controllability analysis to the HLMN and detected driver metabolites. The driver metabolites tend to have strong ability to influence the states of other metabolites and weak susceptibility to be influenced by the states of others. In addition, the metabolites were classified into three classes: critical, high-frequency and low-frequency driver metabolites. Among the identified 36 critical driver metabolites, 27 metabolites were found to be essential; the high-frequency driver metabolites tend to participate in different metabolic pathways, which are important in regulating the whole metabolic systems. Moreover, we explored some other possible connections between the structural controllability theory and the HLMN, and find that transport reactions and the environment play important roles in the human liver metabolism. Conclusion There are interesting connections between the structural controllability theory and the human liver metabolism: driver metabolites have essential biological functions; the crucial role of extracellular metabolites and transport reactions in controlling the HLMN highlights the importance of the environment in the health of human liver metabolism. PMID:24885538

Proteomic Profiles of Adipose and Liver Tissues from an Animal Model of Metabolic Syndrome Fed Purple Vegetables

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Hala M Ayoub

2018-04-01

Full Text Available Metabolic Syndrome (MetS is a complex disorder that predisposes an individual to Cardiovascular Diseases and type 2 Diabetes Mellitus. Proteomics and bioinformatics have proven to be an effective tool to study complex diseases and mechanisms of action of nutrients. We previously showed that substitution of the majority of carbohydrate in a high fat diet by purple potatoes (PP or purple carrots (PC improved insulin sensitivity and hypertension in an animal model of MetS (obese Zucker rats compared to a control sucrose-rich diet. In the current study, we used TMT 10plex mass tag combined with LC-MS/MS technique to study proteomic modulation in the liver (n = 3 samples/diet and adipose tissue (n = 3 samples/diet of high fat diet-fed rats with or without substituting sucrose for purple vegetables, followed by functional enrichment analysis, in an attempt to elucidate potential molecular mechanisms responsible for the phenotypic changes seen with purple vegetable feeding. Protein folding, lipid metabolism and cholesterol efflux were identified as the main modulated biological themes in adipose tissue, whereas lipid metabolism, carbohydrate metabolism and oxidative stress were the main modulated themes in liver. We propose that enhanced protein folding, increased cholesterol efflux and higher free fatty acid (FFA re-esterification are mechanisms by which PP and PC positively modulate MetS pathologies in adipose tissue, whereas, decreased de novo lipogenesis, oxidative stress and FFA uptake, are responsible for the beneficial effects in liver. In conclusion, we provide molecular evidence for the reported metabolic health benefits of purple carrots and potatoes and validate that these vegetables are good choices to replace other simple carbohydrate sources for better metabolic health.

Nonalcoholic Fatty Liver Disease: Prevalence, Influence on Age and Sex, and Relationship with Metabolic Syndrome and Insulin Resistance

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Hui-Yun Cheng

2013-12-01

Conclusion: Fatty liver can be considered as the hepatic consequence of metabolic syndrome, specifically IR. There is a high prevalence of metabolic syndrome and fatty liver among the elderly population. Metabolic disorders are closely related to fatty liver; moreover, fatty liver appears to be a good predictor for the clustering of risk factors for metabolic syndrome.

Intracerebroventricular ghrelin treatment affects lipid metabolism in liver of rainbow trout (Oncorhynchus mykiss).

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Velasco, Cristina; Librán-Pérez, Marta; Otero-Rodiño, Cristina; López-Patiño, Marcos A; Míguez, Jesús M; Soengas, José L

2016-03-01

We aimed to elucidate in rainbow trout (Oncorhynchus mykiss) the effects of central ghrelin (GHRL) treatment on the regulation of liver lipid metabolism, and the possible modulatory effect of central GHRL treatment on the simultaneous effects of raised levels of oleate. Thus, we injected intracerebroventricularly (ICV) rainbow trout GHRL in the presence or absence of oleate and evaluated in liver variables related to lipid metabolism. Oleate treatment elicited in liver of rainbow trout decreased lipogenesis and increased oxidative capacity in agreement with previous studies. Moreover, as demonstrated for the first time in fish in the present study, GHRL also acts centrally modulating lipid metabolism in liver, resulting in increased potential for lipogenesis and decreased potential for fatty acid oxidation, i.e. the converse effects to those elicited by central oleate treatment. The simultaneous treatment of GHRL and oleate confirmed these counteractive effects. Thus, the nutrient sensing mechanisms present in hypothalamus, particularly those involved in sensing of fatty acid, are involved in the control of liver energy metabolism in fish, and this control is modulated by the central action of GHRL. These results give support to the notion of hypothalamus as an integrative place for the regulation of peripheral energy metabolism in fish. Copyright © 2016 Elsevier Inc. All rights reserved.

HEPATOKIN1 is a biochemistry-based model of liver metabolism for applications in medicine and pharmacology.

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Berndt, Nikolaus; Bulik, Sascha; Wallach, Iwona; Wünsch, Tilo; König, Matthias; Stockmann, Martin; Meierhofer, David; Holzhütter, Hermann-Georg

2018-06-19

The epidemic increase of non-alcoholic fatty liver diseases (NAFLD) requires a deeper understanding of the regulatory circuits controlling the response of liver metabolism to nutritional challenges, medical drugs, and genetic enzyme variants. As in vivo studies of human liver metabolism are encumbered with serious ethical and technical issues, we developed a comprehensive biochemistry-based kinetic model of the central liver metabolism including the regulation of enzyme activities by their reactants, allosteric effectors, and hormone-dependent phosphorylation. The utility of the model for basic research and applications in medicine and pharmacology is illustrated by simulating diurnal variations of the metabolic state of the liver at various perturbations caused by nutritional challenges (alcohol), drugs (valproate), and inherited enzyme disorders (galactosemia). Using proteomics data to scale maximal enzyme activities, the model is used to highlight differences in the metabolic functions of normal hepatocytes and malignant liver cells (adenoma and hepatocellular carcinoma).

Long-Lasting Improvements in Liver Fat and Metabolism Despite Body Weight Regain After Dietary Weight Loss

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Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L.; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C.; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-01-01

OBJECTIVE Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. RESEARCH DESIGN AND METHODS We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were ra...

High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.

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Christensen, Karen E; Mikael, Leonie G; Leung, Kit-Yi; Lévesque, Nancy; Deng, Liyuan; Wu, Qing; Malysheva, Olga V; Best, Ana; Caudill, Marie A; Greene, Nicholas D E; Rozen, Rima

2015-03-01

Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions. Our goal was to investigate the impact of high folic acid intake on liver disease and methyl metabolism. Folic acid-supplemented diet (FASD, 10-fold higher than recommended) and control diet were fed to male Mthfr(+/+) and Mthfr(+/-) mice for 6 mo to assess gene-nutrient interactions. Liver pathology, folate and choline metabolites, and gene expression in folate and lipid pathways were examined. Liver and spleen weights were higher and hematologic profiles were altered in FASD-fed mice. Liver histology revealed unusually large, degenerating cells in FASD Mthfr(+/-) mice, consistent with nonalcoholic fatty liver disease. High folic acid inhibited MTHFR activity in vitro, and MTHFR protein was reduced in FASD-fed mice. 5-Methyltetrahydrofolate, SAM, and SAM/S-adenosylhomocysteine ratios were lower in FASD and Mthfr(+/-) livers. Choline metabolites, including phosphatidylcholine, were reduced due to genotype and/or diet in an attempt to restore methylation capacity through choline/betaine-dependent SAM synthesis. Expression changes in genes of one-carbon and lipid metabolism were particularly significant in FASD Mthfr(+/-) mice. The latter changes, which included higher nuclear sterol regulatory element-binding protein 1, higher Srepb2 messenger RNA (mRNA), lower farnesoid X receptor (Nr1h4) mRNA, and lower Cyp7a1 mRNA, would lead to greater lipogenesis and reduced cholesterol catabolism into bile. We suggest that high folic acid consumption reduces MTHFR protein and activity levels, creating a pseudo-MTHFR deficiency. This deficiency results in hepatocyte degeneration, suggesting a 2-hit mechanism whereby mutant hepatocytes cannot

S-Adenosylmethionine metabolism and its relation to polyamine synthesis in rat liver. Effect of nutritional state, adrenal function, some drugs and partial hepatectomy

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Eloranta, Terho O.; Raina, Aarne M.

1977-01-01

S-Adenosylmethionine metabolism and its relation to the synthesis and accumulation of polyamines was studied in rat liver under various nutritional conditions, in adrenalectomized or partially hepatectomized animals and after treatment with cortisol, thioacetamide or methylglyoxal bis(guanylhydrazone) {1,1′-[(methylethanediylidine)dinitrilo]diguanidine}. Starvation for 2 days only slightly affected S-adenosylmethionine metabolism. The ratio of spermidine/spermine decreased markedly, but the concentration of total polyamines did not change significantly. The activity of S-adenosylmethionine decarboxylase initially decreased and then increased during prolonged starvation. This increase was dependent on intact adrenals. Re-feeding of starved animals caused a rapid but transient stimulation of polyamine synthesis and also increased the concentrations of S-adenosylmethionine and S-adenosylhomocysteine. Similarly, cortisol treatment enhanced the synthesis of polyamines, S-adenosylmethionine and S-adenosylhomocysteine. Feeding with a methionine-deficient diet for 7–14 days profoundly increased the concentration of spermidine, whereas the concentrations of total polyamines and of S-adenosylmethionine showed no significant changes. The results show that nutritional state and adrenal function play a significant role in the regulation of hepatic metabolism of S-adenosylmethionine and polyamines. They further indicate that under a variety of physiological and experimental conditions the concentrations of S-adenosylmethionine and of total polyamines remain fairly constant and that changes in polyamine metabolism are not primarily connected with changes in the accumulation of S-adenosylmethionine or S-adenosylhomocysteine. PMID:597268

Early postnatal feed restriction reduces liver connective tissue levels and affects H3K9 acetylation state of regulated genes associated with protein metabolism in low birth weight pigs.

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Nebendahl, Constance; Görs, Solvig; Albrecht, Elke; Krüger, Ricarda; Martens, Karen; Giller, Katrin; Hammon, Harald M; Rimbach, Gerald; Metges, Cornelia C

2016-03-01

Intrauterine growth retardation is associated with metabolic consequences in adulthood. Since our previous data indicate birth weight-dependent effects of feed restriction (R) on protein degradation processes in the liver, it should be investigated whether effects on connective tissue turnover are obvious and could be explained by global changes of histone H3K9me3 and H3K9ac states in regulated genes. For this purpose, female littermate pigs with low (U) or normal (N) birth weight were subjected to 3-week R (60% of ad libitum fed controls) with subsequent refeeding (REF) for further 5 weeks. The 3-week R-period induced a significant reduction of connective tissue area by 43% in the liver of U animals at 98 d of age, which was not found in age-matched N animals. Of note, after REF at 131 d of age, in previously feed-restricted U animals (UR), the percentage of mean connective tissue was only 53% of ad libitum fed controls (UK), indicating a persistent effect. In U animals, R induced H3K9 acetylation of regulated genes (e.g. XBP1, ERLEC1, GALNT2, PTRH2), which were inter alia associated with protein metabolism. In contrast, REF was mostly accompanied by deacetylation in U and N animals. Thus, our epigenetic data may give a first explanation for the observed birth weight-dependent differences in this connective tissue phenotype. Copyright © 2015 Elsevier Inc. All rights reserved.

Metabolism of 1-[14C]nitropyrene in isolated perfused rat livers

International Nuclear Information System (INIS)

Bond, J.A.; Medinsky, M.A.; Dutcher, J.S.

1984-01-01

1-Nitropyrene (1-NP), a constituent of diesel exhaust, is carcinogenic to rats and is a bacterial and mammalian mutagen. Biliary and fecal excretion of 1-NP metabolites are the major routes of excretion in rats, suggesting that hepatic metabolism plays a dominant role in determining the biological fate of 1-NP. The purpose of this investigation was to quantitate 1-[14C]NP metabolites formed in isolated perfused rat livers and excreted in bile from rats. Perfused rat livers displayed a capacity for oxidation, reduction, acetylation, and conjugation of 1-NP (or its metabolites). Reduction of 1-NP followed by N-acetylation was the major metabolic pathway observed in the perfused livers. Acetylaminopyrene (AAP) was the major metabolite detected, with total quantities (150 nmol) accounting for about 60% of the total 1-[14C]NP dose (258 nmol) added to the perfusate. Considerably smaller quantities of aminopyrene and hydroxynitropyrenes were also detected. Livers perfused with 1-[14C]NP excreted about 36 nmol equivalents of 1-[14C]NP (12% of the total 1-NP dose) in bile after 60 min. Some of the biliary metabolites were tentatively identified as metabolites of the mercapturic acid pathway. The spectrum of biliary metabolites was qualitatively identical to that seen in bile from intact rats. Quantities of 14C covalently bound to hepatic macromolecules from perfused livers were 0.4 nmol 1-NP eq/g liver. The data from this study indicate that the liver may be an important site for metabolism of 1-NP

H2S-induced S-sulfhydration of pyruvate carboxylase contributes to gluconeogenesis in liver cells.

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Ju, YoungJun; Untereiner, Ashley; Wu, Lingyun; Yang, Guangdong

2015-11-01

Cystathionine gamma-lyase (CSE)-derived hydrogen sulfide (H(2)S) possesses diverse roles in the liver, affecting lipoprotein synthesis, insulin sensitivity, and mitochondrial biogenesis. H(2)S S-sulfhydration is now proposed as a major mechanism for H(2)S-mediated signaling. Pyruvate carboxylase (PC) is an important enzyme for gluconeogenesis. S-sulfhydration regulation of PC by H(2)S and its implication in gluconeogenesis in the liver have been unknown. Gene expressions were analyzed by real-time PCR and western blotting, and protein S-sulfhydration was assessed by both modified biotin switch assay and tag switch assay. Glucose production and PC activity was measured with coupled enzyme assays, respectively. Exogenously applied H(2)S stimulates PC activity and gluconeogenesis in both HepG2 cells and mouse primary liver cells. CSE overexpression enhanced but CSE knockout reduced PC activity and gluconeogenesis in liver cells, and blockage of PC activity abolished H(2)S-induced gluconeogenesis. H(2)S had no effect on the expressions of PC mRNA and protein, while H(2)S S-sulfhydrated PC in a dithiothreitol-sensitive way. PC S-sulfhydration was significantly strengthened by CSE overexpression but attenuated by CSE knockout, suggesting that H(2)S enhances glucose production through S-sulfhydrating PC. Mutation of cysteine 265 in human PC diminished H(2)S-induced PC S-sulfhydration and activity. In addition, high-fat diet feeding of mice decreased both CSE expression and PC S-sulfhydration in the liver, while glucose deprivation of HepG2 cells stimulated CSE expression. CSE/H(2)S pathway plays an important role in the regulation of glucose production through S-sulfhydrating PC in the liver. Tissue-specific regulation of CSE/H(2)S pathway might be a promising therapeutic target of diabetes and other metabolic syndromes. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of cryopreserved trout hepatocytes and liver S9 fractions as in vitro tools for bioaccumulation assessment of chemicals that undergo biotransformation in fish

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U.S. Environmental Protection Agency — The purpose of this study was to compare two in vitro systems, cryopreserved trout hepatocytes and trout liver S9 fractions, used to predict in vivo levels of...

Correlation between liver function tests and metabolic syndrome in hepatitis-free elderly

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Hung-Sheng Shang

2015-01-01

Full Text Available Background: We aimed to investigate the relationship between liver function tests (LFTs and metabolic syndrome (MetS as several studies have shown positive correlations between some of the LFTs, including alanine aminotransferase (ALT and γ-glutamyl transpeptidase (γ-GT, and MetS but have not fully explored the same in the elderly. Owing to the progress in public health, the aging of the general population becomes a major issue. Design: We enrolled subjects aged over 60 years who underwent routine health checkups in a Health Screening Center after excluding subjects with a history of hepatitis B or C infection, excessive alcohol consumption, liver fibrosis, cirrhosis, acute hepatitis, diabetes, hypertension, dyslipidemia, cardiovascular disease, or receiving medications for these diseases. Finally, 9,282 participants were eligible for analysis. Statistical Analysis: All data were tested for normal distribution with the Kolmogorov-Smirnov test and for homogeneity of variances with the Levene′s test. A t-test was used to evaluate the differences between the two groups. Univariate and multivariate regressions were used to observe correlations between different parameters. Receiver operating characteristic curves of each LFT were used to predict MetS. Areas under curves and 95% confidence interval were also estimated and compared. Results: With the exception of aspartate aminotransferase and α-fetal protein, the results of LFTs, including total and direct bilirubin, alkaline phosphatase (ALP, ALT, and γ-GT, were altered in the group with MetS. Furthermore, the levels of γ-GT in men and ALP in women were independently associated with all MetS components and had the highest areas under receiver operating characteristic curves. Conclusion: Abnormal LFTs are highly correlated with MetS in the hepatitis-free elderly, with levels of γ-GT in men and ALP in women being the most important factors. LFTs may represent an auxiliary tool for the

The in utero programming effect of increased maternal androgens and a direct fetal intervention on liver and metabolic function in adult sheep.

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Hogg, Kirsten; Wood, Charlotte; McNeilly, Alan S; Duncan, W Colin

2011-01-01

Epigenetic changes in response to external stimuli are fast emerging as common underlying causes for the pre-disposition to adult disease. Prenatal androgenization is one such model that results in reproductive and metabolic features that are present in conditions such as polycystic ovary syndrome (PCOS). We examined the effect of prenatal androgens on liver function and metabolism of adult sheep. As non-alcoholic fatty liver disease is increased in PCOS we hypothesized that this, and other important liver pathways including metabolic function, insulin-like growth factor (IGF) and steroid receptivity, would be affected. Pregnant ewes received vehicle control (C; n = 5) or testosterone propionate (TP; n = 9) twice weekly (100 mg; i.m) from d62-102 (gestation 147 days). In a novel treatment paradigm, a second cohort received a direct C (n = 4) or TP (20 mg; n = 7) fetal injection at d62 and d82. In adults, maternal TP exposure resulted in increased insulin secretion to glucose load (Pfetal intervention (C and TP) led to early fatty liver changes in all animals without differential changes in insulin secretion. Furthermore, hepatic phosphoenolpyruvate carboxykinase (PEPCK) was up-regulated in the fetal controls (Pfetal TP (Pfetal TP exposure. Adult liver metabolism and signaling can be altered by early exposure to sex steroids implicating epigenetic regulation of metabolic disturbances that are common in PCOS.

Long-lasting improvements in liver fat and metabolism despite body weight regain after dietary weight loss.

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Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-11-01

Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were randomized to either reduced carbohydrates or reduced fat content. Before, directly after diet, and at an average of 24 (range, 17-36) months follow-up, we assessed body fat distribution by magnetic resonance imaging and markers of liver function and insulin resistance. Body weight decreased with diet but had increased again at follow-up. Subjects also partially regained abdominal subcutaneous and visceral adipose tissue. In contrast, intrahepatic fat decreased with diet and remained reduced at follow-up (7.8 ± 9.8% [baseline], 4.5 ± 5.9% [6 months], and 4.7 ± 5.9% [follow-up]). Similar patterns were observed for markers of liver function, whole-body insulin sensitivity, and hepatic insulin resistance. Changes in intrahepatic fat und intrahepatic function were independent of macronutrient composition during intervention and were most effective in subjects with nonalcoholic fatty liver disease at baseline. A 6-month hypocaloric diet induced improvements in hepatic fat, liver test results, and insulin resistance despite regaining of weight up to 2 years after the active intervention. Body weight and adiposity measurements may underestimate beneficial long-term effects of dietary interventions.

Scaffold-free 3D bio-printed human liver tissue stably maintains metabolic functions useful for drug discovery.

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Kizawa, Hideki; Nagao, Eri; Shimamura, Mitsuru; Zhang, Guangyuan; Torii, Hitoshi

2017-07-01

The liver plays a central role in metabolism. Although many studies have described in vitro liver models for drug discovery, to date, no model has been described that can stably maintain liver function. Here, we used a unique, scaffold-free 3D bio-printing technology to construct a small portion of liver tissue that could stably maintain drug, glucose, and lipid metabolism, in addition to bile acid secretion. This bio-printed normal human liver tissue maintained expression of several kinds of hepatic drug transporters and metabolic enzymes that functioned for several weeks. The bio-printed liver tissue displayed glucose production via cAMP/protein kinase A signaling, which could be suppressed with insulin. Bile acid secretion was also observed from the printed liver tissue, and it accumulated in the culture medium over time. We observed both bile duct and sinusoid-like structures in the bio-printed liver tissue, which suggested that bile acid secretion occurred via a sinusoid-hepatocyte-bile duct route. These results demonstrated that our bio-printed liver tissue was unique, because it exerted diverse liver metabolic functions for several weeks. In future, we expect our bio-printed liver tissue to be applied to developing new models that can be used to improve preclinical predictions of long-term toxicity in humans, generate novel targets for metabolic liver disease, and evaluate biliary excretion in drug development.

Heart over mind: metabolic control of white adipose tissue and liver.

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Nakamura, Michinari; Sadoshima, Junichi

2014-12-01

Increasing evidence suggests that the heart controls the metabolism of peripheral organs. Olson and colleagues previously demonstrated that miR‐208a controls systemic energy homeostasis through the regulation of MED13 in cardiomyocytes (Grueter et al, 2012). In their follow‐up study in this issue of EMBO Molecular Medicine, white adipose tissue (WAT) and liver are identified as the physiological targets of cardiac MED13 signaling, most likely through cardiac‐derived circulating factors, which boost energy consumption by upregulating metabolic gene expression and increasing mitochondrial numbers (Baskin et al, 2014). In turn, increased energy expenditure in WAT and the liver confers leanness. These findings strengthen the evidence of metabolic crosstalk between the heart and peripheral tissues through cardiokines and also set the stage for the development of novel treatments for metabolic syndrome.

High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice12345

Science.gov (United States)

Christensen, Karen E; Mikael, Leonie G; Leung, Kit-Yi; Lévesque, Nancy; Deng, Liyuan; Wu, Qing; Malysheva, Olga V; Best, Ana; Caudill, Marie A; Greene, Nicholas DE

2015-01-01

Background: Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions. Objective: Our goal was to investigate the impact of high folic acid intake on liver disease and methyl metabolism. Design: Folic acid–supplemented diet (FASD, 10-fold higher than recommended) and control diet were fed to male Mthfr+/+ and Mthfr+/− mice for 6 mo to assess gene-nutrient interactions. Liver pathology, folate and choline metabolites, and gene expression in folate and lipid pathways were examined. Results: Liver and spleen weights were higher and hematologic profiles were altered in FASD-fed mice. Liver histology revealed unusually large, degenerating cells in FASD Mthfr+/− mice, consistent with nonalcoholic fatty liver disease. High folic acid inhibited MTHFR activity in vitro, and MTHFR protein was reduced in FASD-fed mice. 5-Methyltetrahydrofolate, SAM, and SAM/S-adenosylhomocysteine ratios were lower in FASD and Mthfr+/− livers. Choline metabolites, including phosphatidylcholine, were reduced due to genotype and/or diet in an attempt to restore methylation capacity through choline/betaine-dependent SAM synthesis. Expression changes in genes of one-carbon and lipid metabolism were particularly significant in FASD Mthfr+/− mice. The latter changes, which included higher nuclear sterol regulatory element-binding protein 1, higher Srepb2 messenger RNA (mRNA), lower farnesoid X receptor (Nr1h4) mRNA, and lower Cyp7a1 mRNA, would lead to greater lipogenesis and reduced cholesterol catabolism into bile. Conclusions: We suggest that high folic acid consumption reduces MTHFR protein and activity levels, creating a pseudo-MTHFR deficiency. This deficiency results in hepatocyte degeneration, suggesting a 2

Sexually dimorphic effects of maternal nutrient reduction on expression of genes regulating cortisol metabolism in fetal baboon adipose and liver tissues.

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Guo, Chunming; Li, Cun; Myatt, Leslie; Nathanielsz, Peter W; Sun, Kang

2013-04-01

Maternal nutrient reduction (MNR) during fetal development may predispose offspring to chronic disease later in life. Increased regeneration of active glucocorticoids by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in metabolic tissues is fundamental to the developmental programming of metabolic syndrome, but underlying mechanisms are unknown. Hexose-6-phosphate dehydrogenase (H6PD) generates NADPH, the cofactor for 11β-HSD1 reductase activity. CCAAT/enhancer binding proteins (C/EBPs) and the glucocorticoid receptor (GR) regulate 11β-HSD1 expression. We hypothesize that MNR increases expression of fetal C/EBPs, GR, and H6PD, thereby increasing expression of 11β-HSD1 and reductase activity in fetal liver and adipose tissues. Pregnant MNR baboons ate 70% of what controls ate from 0.16 to 0.9 gestation (term, 184 days). Cortisol levels in maternal and fetal circulations increased in MNR pregnancies at 0.9 gestation. MNR increased expression of 11β-HSD1; H6PD; C/EBPα, -β, -γ; and GR in female but not male perirenal adipose tissue and in male but not female liver at 0.9 gestation. Local cortisol level and its targets PEPCK1 and PPARγ increased correspondingly in adipose and liver tissues. C/EBPα and GR were found to be bound to the 11β-HSD1 promoter. In conclusion, sex- and tissue-specific increases of 11β-HSD1, H6PD, GR, and C/EBPs may contribute to sexual dimorphism in the programming of exaggerated cortisol regeneration in liver and adipose tissues and offsprings' susceptibility to metabolic syndrome.

Estimation of liver glucose metabolism after refeeding

International Nuclear Information System (INIS)

Rognstad, R.

1987-01-01

Refeeding or infusing glucose to rats fasted for 24 hr or more causes rapid liver glycogen synthesis, the carbon source now considered to be largely from gluconeogenesis. While substrate cycling between plasma glucose and liver glucose-6P is known to occur, this cycling has apparently been ignored when calculations are made of % contribution of direct and indirect pathways to liver glycogen synthesis, or when hepatic glucose output is calculated from glucose turnover minus the glucose infusion rate. They show that, isotopically, an estimate of the fluxes of liver glucokinase and glucose-6-phosphatase is required to quantitate sources of carbon for liver glycogen synthesis, and to measure hepatic glucose output (or uptake). They propose a method to estimate these fluxes, involving a short infusion of a 14 C labelled gluconeogenic precursor plus (6T)glucose, with determination of isotopic yields in liver glycogen and total glucose. Given also the rate of liver glycogen synthesis, this procedure permits the estimation of net gluconeogenesis and hepatic glucose output or uptake. Also, in vitro evidence against the notion of a drastic zonation of liver carbohydrate metabolism is presented, e.g. raising the glucose concentration from 10 to 25 mM increases the 14 C yield from H 14 CO 3 - in lactate, with the increased pyruvate kinase flux and decreased gluconeogenesis occurring in the same cell type, not opposing pathways in different hepatocyte types (as has been postulated by some to occur in vivo after refeeding

Liver fat content in type 2 diabetes: relationship with hepatic perfusion and substrate metabolism

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Rijzewijk, Luuk J.; van der Meer, Rutger W.; Lubberink, Mark; Lamb, Hildo J.; Romijn, Johannes A.; de Roos, Albert; Twisk, Jos W.; Heine, Robert J.; Lammertsma, Adriaan A.; Smit, Johannes W. A.; Diamant, Michaela

2010-01-01

Hepatic steatosis is common in type 2 diabetes. It is causally linked to the features of the metabolic syndrome, liver cirrhosis, and cardiovascular disease. Experimental data have indicated that increased liver fat may impair hepatic perfusion and metabolism. The aim of the current study was to

Risk assessment of silica nanoparticles on liver injury in metabolic syndrome mice induced by fructose.

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Li, Jianmei; He, Xiwei; Yang, Yang; Li, Mei; Xu, Chenke; Yu, Rong

2018-07-01

This study aims to assess the effects and the mechanisms of silica nanoparticles (SiNPs) on hepatotoxicity in both normal and metabolic syndrome mouse models induced by fructose. Here, we found that SiNPs exposure lead to improved insulin resistance in metabolic syndrome mice, but markedly worsened hepatic ballooning, inflammation infiltration, and fibrosis. Moreover, SiNPs exposure aggravated liver injury in metabolic syndrome mice by causing serious DNA damage. Following SiNPs exposure, liver superoxide dismutase and catalase activities in metabolic syndrome mice were stimulated, which is accompanied by significantly increased malondialdehyde and 8-hydroxy-2-deoxyguanosine levels as compared to normal mice. Scanning electron microscope (SEM) revealed that SiNPs were more readily deposited in the liver mitochondria of metabolic syndrome mice, resulting in more severe mitochondrial injury as compared to normal mice. We speculated that SiNPs-induced mitochondrial injury might be the cause of hepatic oxidative stress, which further lead to a series of liver lesions as observed in mice following SiNPs exposure. Based on these results, it is likely that SiNPs will increase the risk and severity of liver disease in individuals with metabolic syndrome. Therefore, SiNPs should be used cautiously in food additives and clinical settings. Copyright © 2018 Elsevier B.V. All rights reserved.

Sox17 regulates liver lipid metabolism and adaptation to fasting.

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Samuel Rommelaere

Full Text Available Liver is a major regulator of lipid metabolism and adaptation to fasting, a process involving PPARalpha activation. We recently showed that the Vnn1 gene is a PPARalpha target gene in liver and that release of the Vanin-1 pantetheinase in serum is a biomarker of PPARalpha activation. Here we set up a screen to identify new regulators of adaptation to fasting using the serum Vanin-1 as a marker of PPARalpha activation. Mutagenized mice were screened for low serum Vanin-1 expression. Functional interactions with PPARalpha were investigated by combining transcriptomic, biochemical and metabolic approaches. We characterized a new mutant mouse in which hepatic and serum expression of Vanin-1 is depressed. This mouse carries a mutation in the HMG domain of the Sox17 transcription factor. Mutant mice display a metabolic phenotype featuring lipid abnormalities and inefficient adaptation to fasting. Upon fasting, a fraction of the PPARα-driven transcriptional program is no longer induced and associated with impaired fatty acid oxidation. The transcriptional phenotype is partially observed in heterozygous Sox17+/- mice. In mutant mice, the fasting phenotype but not all transcriptomic signature is rescued by the administration of the PPARalpha agonist fenofibrate. These results identify a novel role for Sox17 in adult liver as a modulator of the metabolic adaptation to fasting.

Immunosuppressive and postoperative effects of orthotopic liver transplantation on bone metabolism

NARCIS (Netherlands)

Guichelaar, MMJ; Malinchoc, M; Sibonga, J; Clarke, BL; Hay, JE

Bone loss occurs early after orthotopic liver transplantation (OLT) in all liver transplant recipients and leads to postoperative fractures, especially in cholestatic patients with the lowest bone mass. Little is known about the underlying changes in bone metabolism after OLT or about the etiology

Chlamydia pneumoniae acute liver infection affects hepatic cholesterol and triglyceride metabolism in mice.

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Marangoni, Antonella; Fiorino, Erika; Gilardi, Federica; Aldini, Rita; Scotti, Elena; Nardini, Paola; Foschi, Claudio; Donati, Manuela; Montagnani, Marco; Cevenini, Monica; Franco, Placido; Roda, Aldo; Crestani, Maurizio; Cevenini, Roberto

2015-08-01

Chlamydia pneumoniae has been linked to atherosclerosis, strictly associated with hyperlipidemia. The liver plays a central role in the regulation of lipid metabolism. Since in animal models C. pneumoniae can be found at hepatic level, this study aims to elucidate whether C. pneumoniae infection accelerates atherosclerosis by affecting lipid metabolism. Thirty Balb/c mice were challenged intra-peritoneally with C. pneumoniae elementary bodies and thirty with Chlamydia trachomatis, serovar D. Thirty mice were injected with sucrose-phosphate-glutamate buffer, as negative controls. Seven days after infection, liver samples were examined both for presence of chlamydia and expression of genes involved in inflammation and lipid metabolism. C. pneumoniae was isolated from 26 liver homogenates, whereas C. trachomatis was never re-cultivated (P triglycerides levels compared both with negative controls (P metabolism. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Rb and p53 Liver Functions Are Essential for Xenobiotic Metabolism and Tumor Suppression.

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Sathidpak Nantasanti

Full Text Available The tumor suppressors Retinoblastoma (Rb and p53 are frequently inactivated in liver diseases, such as hepatocellular carcinomas (HCC or infections with Hepatitis B or C viruses. Here, we discovered a novel role for Rb and p53 in xenobiotic metabolism, which represent a key function of the liver for metabolizing therapeutic drugs or toxins. We demonstrate that Rb and p53 cooperate to metabolize the xenobiotic 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC. DDC is metabolized mainly by cytochrome P450 (Cyp3a enzymes resulting in inhibition of heme synthesis and accumulation of protoporphyrin, an intermediate of heme pathway. Protoporphyrin accumulation causes bile injury and ductular reaction. We show that loss of Rb and p53 resulted in reduced Cyp3a expression decreased accumulation of protoporphyrin and consequently less ductular reaction in livers of mice fed with DDC for 3 weeks. These findings provide strong evidence that synergistic functions of Rb and p53 are essential for metabolism of DDC. Because Rb and p53 functions are frequently disabled in liver diseases, our results suggest that liver patients might have altered ability to remove toxins or properly metabolize therapeutic drugs. Strikingly the reduced biliary injury towards the oxidative stress inducer DCC was accompanied by enhanced hepatocellular injury and formation of HCCs in Rb and p53 deficient livers. The increase in hepatocellular injury might be related to reduce protoporphyrin accumulation, because protoporphrin is well known for its anti-oxidative activity. Furthermore our results indicate that Rb and p53 not only function as tumor suppressors in response to carcinogenic injury, but also in response to non-carcinogenic injury such as DDC.

Diagnosis and management of non-alcoholic fatty liver disease and related metabolic disorders: Consensus statement from the Study Group of Liver and Metabolism, Chinese Society of Endocrinology

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Gao, Xin; Fan, Jian-Gao

2013-01-01

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in Western countries, affecting 20%–33% of the general population. Large population-based surveys in China indicate a prevalence of approximately 15%–30%. Worldwide, including in China, the prevalence of NAFLD has increased rapidly in parallel with regional trends of obesity, type2 diabetes and metabolic syndrome. In addition, NAFLD has contributed significantly to increased overall, as well as cardiovascular and liver-related, mortality in the general population. In view of rapid advances in research into NAFLD in recent years, this consensus statement provides a brief update on the progress in the field and suggests preferred approaches for the comprehensive management of NAFLD and its related metabolic diseases. PMID:23560695

Long-Lasting Improvements in Liver Fat and Metabolism Despite Body Weight Regain After Dietary Weight Loss

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Haufe, Sven; Haas, Verena; Utz, Wolfgang; Birkenfeld, Andreas L.; Jeran, Stephanie; Böhnke, Jana; Mähler, Anja; Luft, Friedrich C.; Schulz-Menger, Jeanette; Boschmann, Michael; Jordan, Jens; Engeli, Stefan

2013-01-01

OBJECTIVE Weight loss reduces abdominal and intrahepatic fat, thereby improving metabolic and cardiovascular risk. Yet, many patients regain weight after successful diet-induced weight loss. Long-term changes in abdominal and liver fat, along with liver test results and insulin resistance, are not known. RESEARCH DESIGN AND METHODS We analyzed 50 overweight to obese subjects (46 ± 9 years of age; BMI, 32.5 ± 3.3 kg/m2; women, 77%) who had participated in a 6-month hypocaloric diet and were randomized to either reduced carbohydrates or reduced fat content. Before, directly after diet, and at an average of 24 (range, 17–36) months follow-up, we assessed body fat distribution by magnetic resonance imaging and markers of liver function and insulin resistance. RESULTS Body weight decreased with diet but had increased again at follow-up. Subjects also partially regained abdominal subcutaneous and visceral adipose tissue. In contrast, intrahepatic fat decreased with diet and remained reduced at follow-up (7.8 ± 9.8% [baseline], 4.5 ± 5.9% [6 months], and 4.7 ± 5.9% [follow-up]). Similar patterns were observed for markers of liver function, whole-body insulin sensitivity, and hepatic insulin resistance. Changes in intrahepatic fat und intrahepatic function were independent of macronutrient composition during intervention and were most effective in subjects with nonalcoholic fatty liver disease at baseline. CONCLUSIONS A 6-month hypocaloric diet induced improvements in hepatic fat, liver test results, and insulin resistance despite regaining of weight up to 2 years after the active intervention. Body weight and adiposity measurements may underestimate beneficial long-term effects of dietary interventions. PMID:23963894

Independent and supra-additive effects of alcohol consumption, cigarette smoking, and metabolic syndrome on the elevation of serum liver enzyme levels.

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Eun Young Park

Full Text Available We investigated the independent and combined effects of alcohol consumption, cigarette smoking and metabolic syndrome on abnormal liver function, i.e., the elevation of serum liver enzyme levels. Participants of a Korean population-based prospective cohort aged ≥30 years without liver disease, diabetes, or cardiovascular diseases were included. Information on alcohol consumption, smoking status, and metabolic syndrome, defined as per the criteria of the Adult Treatment Panel III, were applied to evaluate their impact on serum levels of aspartate aminotransferase (AST, alanine aminotransferase (ALT, and gamma-glutamyl transferase (GGT. Alcohol consumption, cigarette smoking and metabolic syndrome were the significant individual factors that elevated serum liver enzyme levels. Supra-additive effects of metabolic syndrome and either alcohol consumption or cigarette smoking were also identified. The combination of heavy drinking (≥24 g/day and metabolic syndrome conferred an effect that was higher than the sum of the two individual effects (Synergic Index (SI: AST, 2.37 [1.20-4.67]; GGT, 1.91 [1.17-3.13]. Only GGT level (odds ratio 6.04 [3.68-9.94], SI 2.33 [1.24-4.41] was significantly elevated when the effect of moderate drinking (20 pack years, 1.80 for ≥24 g/day and ≤20 pack years, 2.03 for ≥24 g/day and >20 pack years, while only the combined effect of drinking ≥24 g/day and smoking >20 pack years elevated the AST level (SI 4.55 [3.12-6.61]. The combined effect of cigarette smoking and metabolic syndrome was not supra-additive. To prevent fatty liver disease and other related diseases, a multifactorial prevention strategy that includes limited alcohol consumption, smoking cessation and rectification of adverse metabolic profiles is required.

Global Liver Gene Expression Analysis on a Murine Metabolic Syndrome Model Treated by Low-molecular-weight Lychee Fruit Polyphenol (Oligonol®).

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Uchiyama, Hironobu; Uehara, Kaori; Nagashima, Takayuki; Nakata, Akifumi; Sato, Keisuke; Mihara, Yoshihiro; Komatsu, Ken-Ich; Takanari, Jun; Shimizu, Shigeomi; Wakame, Koji

2016-07-01

Oligonol® (OLG) is a low-molecular-weight lychee fruit polyphenol mainly containing catechin-type monomers and oligomers of proanthocyanidins. Dietary OLG supplementation reportedly improves lipid metabolism disorder and lowers the visceral fat level in animal and human studies. Thus, we investigated the mechanism behind the protective and beneficial effects of OLG on a Western diet (WD)-induced metabolic syndrome (MetS) of a murine model. Using the C57BL/6J mouse for the MetS model, mice were divided into three groups: control (normal diet: ND), Western diet (WD) and WD + 0.5% OLG (OLG) groups. The WD group was fed a high-calorie (high fructose plus high fat) diet for 12 weeks to develop MetS. At week 12, all mice were sacrificed and the blood and liver were obtained for histological and biological examinations and RNA sequencing (RNA-Seq). Body weight, liver weight, plasma triglycerides (TG), total cholesterol (T-Cho) and alanine aminotransferase (ATS) levels of both OLG groups were significantly lower than those of the WD group. On histological examination of the liver, the area of fatty deposits was shown to be suppressed by OLG administration. Expression gene analysis in the liver of WD- versus OLG-fed mice by RNA-Seq showed that 464/45,706 genes exhibited a significant change of expression (corrected p-value metabolism-related genes Lpin1, Adig and Cidea were regulated by OLG administration. OLG may function to suppress MetS and the progression of geriatric diseases in WD-fed mice by regulating the expression of lipid metabolism, inflammation and tumor-related genes in the liver. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Relationship between hepatocellular carcinoma, metabolic syndrome and non-alcoholic fatty liver disease: which clinical arguments?

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Rosmorduc, Olivier

2013-05-01

Obesity and the metabolic syndrome are growing epidemics associated with an increased risk for many types of cancer. In the liver, inflammatory and angiogenic changes due to insulin resistance and fatty liver disease are associated with an increased incidence of liver cancer. Regardless of underlying liver disease, cirrhosis remains the most important risk factor for hepatocellular carcinoma (HCC) although are cases of HCC arising without cirrhosis raise the possibility of a direct carcinogenesis secondary to Non-alcoholic Fatty Liver Disease (NAFLD). Moreover, metabolic syndrome and its different features may also increase the risk of HCC in the setting of chronic liver diseases of other causes such as viral hepatitis or alcohol abuse. Taking into account all these data, it is necessary to better determine the risk of developing HCC in patients with metabolic syndrome to improve the screening guidelines and develop prophylactic treatments in this setting. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Effects of a six-week intraduodenal supplementation with quercetin on liver lipid metabolism and oxidative stress in peripartal dairy cows.

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Stoldt, A-K; Mielenz, M; Nürnberg, G; Sauerwein, H; Esatbeyoglu, T; Wagner, A E; Rimbach, G; Starke, A; Wolffram, S; Metges, C C

2016-05-01

The purpose of this study was to evaluate possible effects of quercetin (Q) on liver lipid metabolism and antioxidative status in periparturient dairy cows. The periparturient period is associated with enormous metabolic changes for dairy cows. Energy needs for incipient lactation are too high to be balanced by feed intake, leading to negative energy balance and body fat mobilization. It has been estimated that this leads to the development of fatty liver in about 50% of cows, which are at high risk for disease. Furthermore, the antioxidative status of these cows may be impaired. Quercetin is a plant flavonoid having hepatoprotective and antioxidative potential and the ability to reduce liver lipid accumulation in monogastric animals. Little information is available in regard to these effects in ruminants. To prevent microbial Q degradation in the rumen, Q was administered via a duodenal fistula to improve systemic availability. Five cows of the Q-treated group received, daily, 100 mg of quercetin dehydrate/kg BW in a 0.9% sodium chloride solution from d -20 until d 20 relative to calving, whereas 5 control (CTR) cows received only a sodium chloride solution. Blood samples were taken weekly and liver biopsies were performed in wk -4, -2, and 3 relative to calving. Cows treated with Q showed a tendency ( = 0.082) for lower liver fat content compared with CTR cows. Liver glycogen, glutathione concentrations, and relative mRNA abundance of genes related to hepatic lipid metabolism and antioxidative status as well as parameters of antioxidative status in plasma were not affected ( > 0.1) by Q supplementation. In conclusion, liver fat content in dairy cows tended to be reduced by Q supplementation, but potential underlying mechanisms remain unclear because analyzed parameters related to hepatic lipid metabolism and antioxidative defense were not altered by Q supplementation.

Dendrobium nobile Lindl. alkaloids regulate metabolism gene expression in livers of mice.

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Xu, Yun-Yan; Xu, Ya-Sha; Wang, Yuan; Wu, Qin; Lu, Yuan-Fu; Liu, Jie; Shi, Jing-Shan

2017-10-01

In our previous studies, Dendrobium nobile Lindl. alkaloids (DNLA) has been shown to have glucose-lowering and antihyperlipidaemia effects in diabetic rats, in rats fed with high-fat diets, and in mice challenged with adrenaline. This study aimed to examine the effects of DNLA on the expression of glucose and lipid metabolism genes in livers of mice. Mice were given DNLA at doses of 10-80 mg/kg, po for 8 days, and livers were removed for total RNA and protein isolation to perform real-time RT-PCR and Western blot analysis. Dendrobium nobile Lindl. alkaloids increased PGC1α at mRNA and protein levels and increased glucose metabolism gene Glut2 and FoxO1 expression. DNLA also increased the expression of fatty acid β-oxidation genes Acox1 and Cpt1a. The lipid synthesis regulator Srebp1 (sterol regulatory element-binding protein-1) was decreased, while the lipolysis gene ATGL was increased. Interestingly, DNLA increased the expression of antioxidant gene metallothionein-1 and NADPH quinone oxidoreductase-1 (Nqo1) in livers of mice. Western blot on selected proteins confirmed these changes including the increased expression of GLUT4 and PPARα. DNLA has beneficial effects on liver glucose and lipid metabolism gene expressions, and enhances the Nrf2-antioxidant pathway gene expressions, which could play integrated roles in regulating metabolic disorders. © 2017 Royal Pharmaceutical Society.

Chimeric mice with humanized liver: Application in drug metabolism and pharmacokinetics studies for drug discovery.

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Naritomi, Yoichi; Sanoh, Seigo; Ohta, Shigeru

2018-02-01

Predicting human drug metabolism and pharmacokinetics (PK) is key to drug discovery. In particular, it is important to predict human PK, metabolite profiles and drug-drug interactions (DDIs). Various methods have been used for such predictions, including in vitro metabolic studies using human biological samples, such as hepatic microsomes and hepatocytes, and in vivo studies using experimental animals. However, prediction studies using these methods are often inconclusive due to discrepancies between in vitro and in vivo results, and interspecies differences in drug metabolism. Further, the prediction methods have changed from qualitative to quantitative to solve these issues. Chimeric mice with humanized liver have been developed, in which mouse liver cells are mostly replaced with human hepatocytes. Since human drug metabolizing enzymes are expressed in the liver of these mice, they are regarded as suitable models for mimicking the drug metabolism and PK observed in humans; therefore, these mice are useful for predicting human drug metabolism and PK. In this review, we discuss the current state, issues, and future directions of predicting human drug metabolism and PK using chimeric mice with humanized liver in drug discovery. Copyright © 2017 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

Interplay between FGF21 and insulin action in the liver regulates metabolism

DEFF Research Database (Denmark)

Emanuelli, Brice; Vienberg, Sara G; Smyth, Graham

2014-01-01

gluconeogenesis in these animals. Improvements in blood sugar were due in part to increased glucose uptake in brown fat, browning of white fat, and overall increased energy expenditure. These effects were preserved even after removal of the main interscapular brown fat pad. In contrast to its retained effects...... of insulin action in the liver by increasing energy metabolism via activation of brown fat and browning of white fat, but intact liver insulin action is required for FGF21 to control hepatic lipid metabolism....

Metabolic syndrome and risk factors for non-alcoholic fatty liver disease

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Mônica Rodrigues de Araújo Souza

2012-03-01

Full Text Available CONTEXT: Non-alcoholic fatty liver disease (NAFLD, hepatic manifestation of metabolic syndrome, has been considered the most common liver disease nowadays, which is also the most frequent cause of elevated transaminases and cryptogenic cirrhosis. The greatest input of fatty acids into the liver and consequent increased beta-oxidation contribute to the formation of free radicals, release of inflammatory cytokines and varying degrees of hepatocytic aggression, whose histological expression may vary from steatosis (HS to non-alcoholic steatohepatitis (NASH. The differentiation of these forms is required by the potential risk of progression to cirrhosis and development of hepatocellular carcinoma. OBJECTIVE: To review the literature about the major risk factors for NAFLD in the context of metabolic syndrome, focusing on underlying mechanisms and prevention. METHOD: PubMed, MEDLINE and SciELO data basis analysis was performed to identify studies describing the link between risk factors for metabolic syndrome and NAFLD. A combination of descriptors was used, non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, metabolic syndrome and risk factors. At the end, 96 clinical and experimental studies, cohorts, meta-analysis and systematic reviews of great impact and scientific relevance to the topic, were selected. RESULTS: The final analysis of all these data, pointed out the central obesity, type 2 diabetes, dyslipidemia and hypertension as the best risk factors related to NAFLD. However, other factors were highlighted, such as gender differences, ethnicity, genetic factors and the role of innate immunity system. How these additional factors may be involved in the installation, progression and disease prognosis is discussed. CONCLUSION: Risk factors for NAFLD in the context of metabolic syndrome expands the prospects to 1 recognize patients with metabolic syndrome at high risk for NAFLD, 2 elucidate pathways common to other co-morbidities, 3

Adrenergic Metabolic and Hemodynamic Effects of Octopamine in the Liver

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Adelar Bracht

2013-11-01

Full Text Available The fruit extracts of Citrus aurantium (bitter orange are traditionally used as weight-loss products and as appetite suppressants. A component of these extracts is octopamine, which is an adrenergic agent. Weight-loss and adrenergic actions are always related to metabolic changes and this work was designed to investigate a possible action of octopamine on liver metabolism. The isolated perfused rat liver was used to measure catabolic and anabolic pathways and hemodynamics. Octopamine increased glycogenolysis, glycolysis, oxygen uptake, gluconeogenesis and the portal perfusion pressure. Octopamine also accelerated the oxidation of exogenous fatty acids (octanoate and oleate, as revealed by the increase in 14CO2 production derived from 14C labeled precursors. The changes in glycogenolysis, oxygen uptake and perfusion pressure were almost completely abolished by α1-adrenergic antagonists. The same changes were partly sensitive to the β-adrenergic antagonist propranolol. It can be concluded that octopamine accelerates both catabolic and anabolic processes in the liver via adrenergic stimulation. Acceleration of oxygen uptake under substrate-free perfusion conditions also means acceleration of the oxidation of endogenous fatty acids, which are derived from lipolysis. All these effects are compatible with an overall stimulating effect of octopamine on metabolism, which is compatible with its reported weight-loss effects in experimental animals.

HDL activation of endothelial sphingosine-1-phosphate receptor-1 (S1P1) promotes regeneration and suppresses fibrosis in the liver.

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Ding, Bi-Sen; Liu, Catherine H; Sun, Yue; Chen, Yutian; Swendeman, Steven L; Jung, Bongnam; Chavez, Deebly; Cao, Zhongwei; Christoffersen, Christina; Nielsen, Lars Bo; Schwab, Susan R; Rafii, Shahin; Hla, Timothy

2016-12-22

Regeneration of hepatic sinusoidal vasculature is essential for non-fibrotic liver regrowth and restoration of its metabolic capacity. However, little is known about how this specialized vascular niche is regenerated. Here we show that activation of endothelial sphingosine-1-phosphate receptor-1 (S1P 1 ) by its natural ligand bound to HDL (HDL-S1P) induces liver regeneration and curtails fibrosis. In mice lacking HDL-S1P, liver regeneration after partial hepatectomy was impeded and associated with aberrant vascular remodeling, thrombosis and peri-sinusoidal fibrosis. Notably, this "maladaptive repair" phenotype was recapitulated in mice that lack S1P 1 in the endothelium. Reciprocally, enhanced plasma levels of HDL-S1P or administration of SEW2871, a pharmacological agonist specific for S1P 1 enhanced regeneration of metabolically functional vasculature and alleviated fibrosis in mouse chronic injury and cholestasis models. This study shows that natural and pharmacological ligands modulate endothelial S1P 1 to stimulate liver regeneration and inhibit fibrosis, suggesting that activation of this pathway may be a novel therapeutic strategy for liver fibrosis.

A liver stress-endocrine nexus promotes metabolic integrity during dietary protein dilution

DEFF Research Database (Denmark)

Maida, Adriano; Zota, Annika; Sjøberg, Kim Anker

2016-01-01

of impaired glucose homeostasis independently of obesity and food intake. DPD-mediated metabolic inefficiency and improvement of glucose homeostasis were independent of uncoupling protein 1 (UCP1), but required expression of liver-derived fibroblast growth factor 21 (FGF21) in both lean and obese mice. FGF21...... expression and secretion as well as the associated metabolic remodeling induced by DPD also required induction of liver-integrated stress response-driven nuclear protein 1 (NUPR1). Insufficiency of select nonessential amino acids (NEAAs) was necessary and adequate for NUPR1 and subsequent FGF21 induction...... and secretion in hepatocytes in vitro and in vivo. Taken together, these data indicate that DPD promotes improved glucose homeostasis through an NEAA insufficiency-induced liver NUPR1/FGF21 axis....

Fasting augments PCB impact on liver metabolism in anadromous Arctic Char

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Vijayan, M.M.; Aluru, N.; Maule, A.G.; Jorgensen, E.H.

2006-01-01

Anadromous arctic char (Salvelinus alpinus) undertake short feeding migrations to seawater every summer and accumulate lipids, while the rest of the year is spent in fresh water where the accumulated lipid reserves are mobilized. We tested the hypothesis that winter fasting and the associated polychlorinated biphenyls' (PCBs) redistribution from lipid depots to critical tissues impair the liver metabolic capacity in these animals. Char were administered Aroclor 1254 (0, 1, 10, and 100 mg/ kg body mass) orally and maintained for 4 months without feeding to mimic seasonal winter fasting, while fed groups (0 and 100 mg Aroclor 1254/kg) were maintained for comparison. A clear dose-related increase in PCB accumulation and cytochrome P4501A (CYP1A) protein content was observed in the livers of fasted fish. This PCB concentration and CYP1A response with the high dose of Aroclor were 1.5-fold and 3-fold greater in the fasted than in the fed fish, respectively. In fed fish, PCB exposure lowered liver glycogen content, whereas none of the other metabolic indicators were significantly affected. In fasted fish, PCB exposure depressed liver glycogen content and activities of glucose-6-phosphate dehydrogenase, alanine aminotransferase, lactate dehydrogenase, and phosphoenolpyruvate carboxykinase and elevated 3-hydroxyacylcoA dehydrogenase activity and glucocorticoid receptor protein expression. There were no significant impacts of PCB on heat shock protein 70 (hsp70) and hsp90 contents in either fed or fasted fish. Collectively, our study demonstrates that winter emaciation associated with the anadromous lifestyle predisposes arctic char to PCB impact on hepatic metabolism including disruption of the adaptive metabolic responses to extended fasting. ?? 2006 Oxford University Press.

Nine-year incident diabetes is predicted by fatty liver indices: the French D.E.S.I.R. study

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Vol Sylviane

2010-06-01

Full Text Available Abstract Background Fatty liver is known to be linked with insulin resistance, alcohol intake, diabetes and obesity. Biopsy and even scan-assessed fatty liver are not always feasible in clinical practice. This report evaluates the predictive ability of two recently published markers of fatty liver: the Fatty Liver Index (FLI and the NAFLD fatty liver score (NAFLD-FLS, for 9-year incident diabetes, in the French general-population cohort: Data from an Epidemiological Study on the Insulin Resistance syndrome (D.E.S.I.R. Methods At baseline, there were 1861 men and 1950 women, non-diabetic, aged 30 to 65 years. Over the follow-up, 203 incident diabetes cases (140 men, 63 women were identified by diabetes-treatment or fasting plasma glucose ≥ 7.0 mmol/l. The FLI includes: BMI, waist circumference, triglycerides and gamma glutamyl transferase, and the NAFLD-FLS: the metabolic syndrome, diabetes, insulin, alanine aminotransferase, and asparate aminotransferase. Logistic regression was used to determine the odds ratios for incident diabetes associated with categories of the fatty liver indices. Results In comparison to those with a FLI Conclusions These fatty liver indexes are simple clinical tools for evaluating the extent of liver fat and they are predictive of incident diabetes. Physicians should screen for diabetes in patients with fatty liver.

Isocaloric high-fat feeding directs hepatic metabolism to handling of nutrient imbalance promoting liver fat deposition

KAUST Repository

Diaz Rua, Ruben; Van Schothorst, E. M.; Keijer, J.; Palou, A.; Oliver, P.

2016-01-01

Background/Objectives: Consumption of fat-rich foods is associated with obesity and related alterations. However, there is a group of individuals, the metabolically obese normal-weight (MONW) subjects, who present normal body weight but have metabolic features characteristic of the obese status, including fat deposition in critical tissues such as liver, recognized as a major cause for the promotion of metabolic diseases. Our aim was to better understand metabolic alterations present in liver of MONW rats applying whole genome transcriptome analysis. Methods: Wistar rats were chronically fed a high-fat diet isocaloric relative to Control animals to avoid the hyperphagia and overweight and to mimic MONW features. Liver transcriptome analysis of both groups was performed. Results: Sustained intake of an isocaloric high-fat diet had a deep impact on the liver transcriptome, mainly affecting lipid metabolism. Although serum cholesterol levels were not affected, circulating triacylglycerols were lower, and metabolic adaptations at gene expression level indicated adaptation toward handling the increased fat content of the diet, an increased triacylglycerol and cholesterol deposition in liver of MONW rats was observed. Moreover, gene expression pointed to increased risk of liver injury. One of the top upregulated genes in this tissue was Krt23, a marker of hepatic disease in humans that was also increased at the protein level.Conclusion:Long-term intake of a high-fat diet, even in the absence of overweight/obesity or increase in classical blood risk biomarkers, promotes a molecular environment leading to hepatic lipid accumulation and increasing the risk of suffering from hepatic diseases.

Isocaloric high-fat feeding directs hepatic metabolism to handling of nutrient imbalance promoting liver fat deposition

KAUST Repository

Diaz Rua, Ruben

2016-03-22

Background/Objectives: Consumption of fat-rich foods is associated with obesity and related alterations. However, there is a group of individuals, the metabolically obese normal-weight (MONW) subjects, who present normal body weight but have metabolic features characteristic of the obese status, including fat deposition in critical tissues such as liver, recognized as a major cause for the promotion of metabolic diseases. Our aim was to better understand metabolic alterations present in liver of MONW rats applying whole genome transcriptome analysis. Methods: Wistar rats were chronically fed a high-fat diet isocaloric relative to Control animals to avoid the hyperphagia and overweight and to mimic MONW features. Liver transcriptome analysis of both groups was performed. Results: Sustained intake of an isocaloric high-fat diet had a deep impact on the liver transcriptome, mainly affecting lipid metabolism. Although serum cholesterol levels were not affected, circulating triacylglycerols were lower, and metabolic adaptations at gene expression level indicated adaptation toward handling the increased fat content of the diet, an increased triacylglycerol and cholesterol deposition in liver of MONW rats was observed. Moreover, gene expression pointed to increased risk of liver injury. One of the top upregulated genes in this tissue was Krt23, a marker of hepatic disease in humans that was also increased at the protein level.Conclusion:Long-term intake of a high-fat diet, even in the absence of overweight/obesity or increase in classical blood risk biomarkers, promotes a molecular environment leading to hepatic lipid accumulation and increasing the risk of suffering from hepatic diseases.

Induced hypoglycemia for 48 hours indicates differential glucose and insulin effects on liver metabolism in dairy cows.

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Kreipe, L; Vernay, M C M B; Oppliger, A; Wellnitz, O; Bruckmaier, R M; van Dorland, H A

2011-11-01

Hypoglycemia is a characteristic condition of early lactation dairy cows and is subsequently dependent on, and may affect, metabolism in the liver. The objective of the present study was to investigate the effects of induced hypoglycemia, maintained for 48 h, on metabolic parameters in plasma and liver of mid-lactation dairy cows. The experiment involved 3 treatments, including a hyperinsulinemic hypoglycemic clamp (HypoG, n=6) to obtain a glucose concentration of 2.5 mmol/L, a hyperinsulinemic euglycemic clamp (EuG, n=6) in which the effect of insulin was studied, and a control treatment with a 0.9% saline solution (NaCl, n=6). Blood samples for measurements of insulin, metabolites, and enzymes were taken at least once per hour. Milk yield was recorded and milk samples were collected before and after treatment. Liver biopsies were obtained before and after treatment to measure mRNA abundance by real-time, quantitative reverse transcription-PCR of 12 candidate genes involved in the main metabolic pathways. Milk yield decreased in HypoG and NaCl cows, whereas it remained unaffected in EuG cows. Energy-corrected milk yield (kg/d) was only decreased in HypoG cows. In plasma, concentration of β-hydroxybutyrate decreased in response to treatment in EuG cows and was lower (0.41±0.04 mmol/L) on d 2 of the treatment compared with that in HypoG and NaCl cows (on average 0.61±0.03 mmol/L, respectively). Nonesterified fatty acids remained unaffected in all treatments. In the liver, differences between treatments for their effects were only observed in case of mitochondrial phosphoenolpyruvate carboxykinase (PEPCKm) and glucose-6-phosphatase (G6PC). In HypoG, mRNA abundance of PEPCKm was upregulated, whereas in EuG and NaCl cows, it was downregulated. The EuG treatment downregulated mRNA expression of G6PC, a marked effect compared with the unchanged transcript expression in NaCl. The mRNA abundance of the insulin receptor remained unaffected in all treatments, and no

Biofabrication of a three-dimensional liver micro-organ as an in vitro drug metabolism model

Energy Technology Data Exchange (ETDEWEB)

Chang, Robert; Sun Wei [Department of Mechanical Engineering and Mechanics, Drexel University, Philadelphia, PA (United States); Emami, Kamal; Wu Honglu, E-mail: rcc34@drexel.ed, E-mail: sunwei@drexel.ed, E-mail: kamal.emami-1@nasa.go, E-mail: honglu.wu-1@nasa.go [Radiation Biophysics Laboratory, Human Adaptation and Countermeasures Office, NASA Johnson Space Center, Houston, TX (United States)

2010-12-15

In their normal in vivo matrix milieu, tissues assume complex well-organized three-dimensional architectures. Therefore, the primary aim in the tissue engineering design process is to fabricate an optimal analog of the in vivo scenario. This challenge can be addressed by applying emerging layered biofabrication approaches in which the precise configuration and composition of cells and bioactive matrix components can recapitulate the well-defined three-dimensional biomimetic microenvironments that promote cell-cell and cell-matrix interactions. Furthermore, the advent of and refinements in microfabricated systems can present physical and chemical cues to cells in a controllable and reproducible fashion unmatched with conventional cultures, resulting in the precise construction of engineered biomimetic microenvironments on the cellular length scale in geometries that are readily parallelized for high throughput in vitro models. As such, the convergence of layered solid freeform fabrication (SFF) technologies along with microfabrication techniques enables the creation of a three-dimensional micro-organ device to serve as an in vitro platform for cell culture, drug screening or to elicit further biological insights, particularly for NASA's interest in a flight-suitable high-fidelity microscale platform to study drug metabolism in space and planetary environments. The proposed model in this paper involves the combinatorial setup of an automated syringe-based, layered direct cell writing bioprinting process with micro-patterning techniques to fabricate a microscale in vitro device housing a chamber of bioprinted three-dimensional liver cell-encapsulated hydrogel-based tissue constructs in defined design patterns that biomimic the cell's natural microenvironment for enhanced biological functionality. In order to assess the structural formability and biological feasibility of such a micro-organ, reproducibly fabricated tissue constructs were biologically

Plasma plasminogen activator inhibitor-1 levels and nonalcoholic fatty liver in individuals with features of metabolic syndrome.

Science.gov (United States)

de Larrañaga, Gabriela; Wingeyer, Silvia Perés; Graffigna, Mabel; Belli, Susana; Bendezú, Karla; Alvarez, Silvia; Levalle, Oscar; Fainboim, Hugo

2008-07-01

Fatty liver represents the liver component of metabolic syndrome and may be involved in plasminogen activator inhibitor-1 (PAI-1) synthesis. We studied plasma PAI-1 levels and relationships with risk factors for metabolic syndrome, including fatty liver, in 170 patients. Liver ultrasound scan was performed on all patients, and a liver biopsy was performed on those patients with chronically elevated transaminase levels. Plasma PAI-1 levels correlated significantly (P < .05) with body mass index, degree of steatosis, insulin resistance, insulin level, waist circumference, triglycerides, and high-density lipoprotein (HDL) -cholesterol. However, only body mass index (beta = .455) and HDL-cholesterol (beta = .293) remained predictors of PAI-1 levels. Liver biopsy revealed a significant correlation (P < .05) between insulin resistance (r = 0.381) or insulin level (r = 0.519) and liver fibrosis. In patients presenting features of metabolic syndrome, plasma PAI-1 levels were mainly conditioned by the whole-body fat content.

High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.

OpenAIRE

Christensen, K. E.; Mikael, L. G.; Leung, K. Y.; Lévesque, N.; Deng, L.; Wu, Q.; Malysheva, O. V.; Best, A.; Caudill, M. A.; Greene, N. D.; Rozen, R.

2015-01-01

Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions.

A tryptophan derivative, ITE, enhances liver cell metabolic functions in vitro

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Zhang, Xiaoqian; Lu, Juan; He, Bin; Tang, Lingling; Liu, Xiaoli; Zhu, Danhua; Cao, Hongcui; Wang, Yingjie; Li, Lanjuan

2017-01-01

Cell encapsulation provides a three-dimensional support by incorporating isolated cells into microcapsules with the goal of simultaneously maintaining cell survival and function, as well as providing active transport for a bioreactor in vitro similarly to that observed in vivo. However, the biotransformation and metabolic functions of the encapsulated cells are not satisfactory for clinical applications. For this purpose, in this study, hepatoma-derived Huh7 cells/C3A cells were treated with 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), an endogenous non-toxic ligand for aryl hydrocarbon receptor, in monolayer cultures and on microspheres. The mRNA and protein levels, as well as the metabolic activities of drug metabolizing enzymes, albumin secretion and urea synthesis were determined. When the Huh7 and C3A cells cultured in a monolayer on two-dimensional surfaces, ITE enhanced the protein levels and the metabolic activities of the major cytochrome P450 (CYP450) enzymes, CYP1A1, CYP1A2, CYP3A4 and CYP1B1, and slightly increased albumin secretion and urea synthesis. Moreover, when cultured on microspheres, ITE also substantially increased the protein levels and metabolic activities of CYP1A1, CYP1A2, CYP3A4 and CYP1B1 in both liver cell lines. On the whole, our findings indicate that ITE enhances the enzymatic activities of major CYP450 enzymes and the metabolic functions of liver cells cultured in monolayer or on microspheres, indicating that it may be utilized to improve the functions of hepatocytes. Thus, it may be used in the future for the treatment of liver diseases. PMID:27959388

Radiorespirometric study of carbohydrate metabolism in childhood liver disease

International Nuclear Information System (INIS)

DaCosta, H.; Shreeve, W.W.; Merchant, S.

1976-01-01

The need for a suitable parameter to evaluate patients with chronic liver disease has been felt for some time, especially in order to judge the response to surgical shunts and the influence of certain drugs and diets on the liver. Since the liver is a major organ for carbohydrate metabolism, it was decided to analyze the in vivo oxidation of such substrates as glucose and galactose labeled with 14 C. Moderately advanced ''Indian childhood cirrhosis'' and idiopathic fatty hepatic infiltration were selected to represent diffuse chronic liver disease. Oral administration of 14 C-U-glucose or 14 C-1-galactose was followed by analyses of 14 CO 2 in breath by liquid scintillation counting. Conversion of 14 C-glucose to 14 CO 2 was accelerated by both diseases. On the other hand, oxidation of 14 C-galactose was slowed in fatty infiltration and was markedly subnormal in Indian childhood cirrhosis

Contribution of liver alcohol dehydrogenase to metabolism of alcohols in rats.

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Plapp, Bryce V; Leidal, Kevin G; Murch, Bruce P; Green, David W

2015-06-05

The kinetics of oxidation of various alcohols by purified rat liver alcohol dehydrogenase (ADH) were compared with the kinetics of elimination of the alcohols in rats in order to investigate the roles of ADH and other factors that contribute to the rates of metabolism of alcohols. Primary alcohols (ethanol, 1-propanol, 1-butanol, 2-methyl-1-propanol, 3-methyl-1-butanol) and diols (1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol) were eliminated in rats with zero-order kinetics at doses of 5-20 mmol/kg. Ethanol was eliminated most rapidly, at 7.9 mmol/kgh. Secondary alcohols (2-propanol-d7, 2-propanol, 2-butanol, 3-pentanol, cyclopentanol, cyclohexanol) were eliminated with first order kinetics at doses of 5-10 mmol/kg, and the corresponding ketones were formed and slowly eliminated with zero or first order kinetics. The rates of elimination of various alcohols were inhibited on average 73% (55% for 2-propanol to 90% for ethanol) by 1 mmol/kg of 4-methylpyrazole, a good inhibitor of ADH, indicating a major role for ADH in the metabolism of the alcohols. The Michaelis kinetic constants from in vitro studies (pH 7.3, 37 °C) with isolated rat liver enzyme were used to calculate the expected relative rates of metabolism in rats. The rates of elimination generally increased with increased activity of ADH, but a maximum rate of 6±1 mmol/kg h was observed for the best substrates, suggesting that ADH activity is not solely rate-limiting. Because secondary alcohols only require one NAD(+) for the conversion to ketones whereas primary alcohols require two equivalents of NAD(+) for oxidation to the carboxylic acids, it appears that the rate of oxidation of NADH to NAD(+) is not a major limiting factor for metabolism of these alcohols, but the rate-limiting factors are yet to be identified. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Metabolically based liver damage pathophysiology in patients with urea cycle disorders - A new hypothesis.

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Ivanovski, Ivan; Ješić, Miloš; Ivanovski, Ana; Garavelli, Livia; Ivanovski, Petar

2017-11-28

The underlying pathophysiology of liver dysfunction in urea cycle disorders (UCDs) is still largely elusive. There is some evidence that the accumulation of urea cycle (UC) intermediates are toxic for hepatocyte mitochondria. It is possible that liver injury is directly caused by the toxicity of ammonia. The rarity of UCDs, the lack of checking of iron level in these patients, superficial knowledge of UC and an underestimation of the metabolic role of fumaric acid, are the main reasons that are responsible for the incomprehension of the mechanism of liver injury in patients suffering from UCDs. Owing to our routine clinical practice to screen for iron overload in severely ill neonates, with the focus on the newborns suffering from acute liver failure, we report a case of citrullinemia with neonatal liver failure and high blood parameters of iron overload. We hypothesize that the key is in the decreased-deficient fumaric acid production in the course of UC in UCDs that causes several sequentially intertwined metabolic disturbances with final result of liver iron overload. The presented hypothesis could be easily tested by examining the patients suffering from UCDs, for liver iron overload. This could be easily performed in countries with a high population and comprehensive national register for inborn errors of metabolism. Providing the hypothesis is correct, neonatal liver damage in patients having UCD can be prevented by the supplementation of pregnant women with fumaric or succinic acid, prepared in the form of iron supplementation pills. After birth, liver damage in patients having UCDs can be prevented by supplementation of these patients with zinc fumarate or zinc succinylate, as well.

Comparative Metabolism Study of Five Protoberberine Alkaloids in Liver Microsomes from Rat, Rhesus Monkey, and Human.

Science.gov (United States)

Li, Yan; Zhou, Yanyan; Si, Nan; Han, Lingyu; Ren, Wei; Xin, Shaokun; Wang, Hongjie; Zuo, Ran; Wei, Xiaolu; Yang, Jian; Zhao, Haiyu; Bian, Baolin

2017-11-01

Protoberberine alkaloids including berberine, palmatine, jatrorrhizine, coptisine, and epiberberine are major components in many medicinal plants. They have been widely used for the treatment of cancer, inflammation, diabetes, depression, hypertension, and various infectious areas. However, the metabolism of five protoberberine alkaloids among different species has not been clarified previously. In order to elaborate on the in vitro metabolism of them, a comparative analysis of their metabolic profile in rat, rhesus monkey, and human liver microsomes was carried out using ultrahigh-performance liquid chromatography coupled with a high-resolution linear trap quadrupole-Orbitrap mass spectrometer (UHPLC-electrospray ionization-Orbitrap MS) for the first time. Each metabolite was identified and semiquantified by its accurate mass data and peak area. Fifteen metabolites were characterized based on accurate MS/MS spectra and the proposed MS/MS fragmentation pathways including demethylation, hydroxylation, and methyl reduction. Among them, the content of berberine metabolites in human liver microsomes was similar with those in rhesus monkey liver microsomes, whereas berberine in rat liver microsomes showed no demethylation metabolites and the content of metabolites showed significant differences with that in human liver microsomes. On the contrary, the metabolism of palmatine in rat liver microsomes resembled that in human liver microsomes. The content of jatrorrhizine metabolites presented obvious differences in all species. The HR-ESI-MS/MS fragmentation behavior of protoberberine alkaloids and their metabolic profile in rat, rhesus monkey, and human liver microsomes were investigated for the first time. The results demonstrated that the biotransformation characteristics of protoberberine alkaloids among different species had similarities as well differences that would be beneficial for us to better understand the pharmacological activities of protoberberine alkaloids

Adipokines, inflammatory mediators, and insulin-resistance parameters may not be good markers of metabolic syndrome after liver transplant.

Science.gov (United States)

Anastácio, Lucilene Rezende; de Oliveira, Marina Chaves; Diniz, Kiara Gonçalves; Ferreira, Adaliene Matos Versiane; Lima, Agnaldo Soares; Correia, Maria Isabel Toulson Davisson; Vilela, Eduardo Garcia

2016-09-01

The role of adipokines in liver transplantation (LTx) recipients who have metabolic syndrome (MetS) has seldom been assessed. The aim of this study was to investigate the concentrations of adipokines, inflammatory mediators, and insulin-resistance markers in liver recipients with MetS and its components. Serum samples from 34 patients (55.9% male; 54.9 ± 13.9 y; 7.7 ± 2.9 y after LTx; 50% presented with MetS) were assessed for adiponectin, resistin, tumor necrosis factor (TNF)-α, monocyte chemoattractant protein (MCP)-1, interleukin (IL)-6, C-reactive protein (CRP), homeostatic model assessment-insulin resistance (HOMA-IR) and free fatty acid (FFA) levels. The dosages were uni- and multivariate analyzed to cover MetS (using the Harmonizing MetS criteria), its components, and dietary intake. A higher concentration of adiponectin (P < 0.05) was observed among patients with MetS (5.2 ± 3.2 μg/mL) compared with those without MetS (3.2 ± 1.2 μg/mL), as well as those with MetS components versus those without them: abdominal obesity (4.6 ± 2.6 μg/mL versus 2.6 ± 0.6 μg/mL), high triacylglycerols (TGs; 5.6 ± 3.1 μg/mL versus 3 ± 0.9 μg/mL) and low high-density lipoprotein (HDL; 6.1 ± 2.7 μg/mL versus 3.3 ± 1.9 μg/mL). Increased TNF-α and HOMA-IR values were seen in patients with abdominal obesity. Patients with high TGs also had greater FFA values. Independent predictors for adiponectin were waist-to-hip ratio, low HDL and high TGs. High TGs and fasting blood glucose were independent predictors for HOMA-IR. Independent predictors could not be identified for CRP, TNF-α, MCP-1, IL-6, or FFA. MetS and its components are related to an increased HOMA-IR concentration and FFA. Adiponectin, resistin, and inflammatory markers, such as TNF-α, IL-6, MCP-1, and CRP, were not associated with MetS in this sample of post-LTx patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Genetic dissection in a mouse model reveals interactions between carotenoids and lipid metabolism[S

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Palczewski, Grzegorz; Widjaja-Adhi, M. Airanthi K.; Amengual, Jaume; Golczak, Marcin; von Lintig, Johannes

2016-01-01

Carotenoids affect a rich variety of physiological functions in nature and are beneficial for human health. However, knowledge about their biological action and the consequences of their dietary accumulation in mammals is limited. Progress in this research field is limited by the expeditious metabolism of carotenoids in rodents and the confounding production of apocarotenoid signaling molecules. Herein, we established a mouse model lacking the enzymes responsible for carotenoid catabolism and apocarotenoid production, fed on either a β-carotene- or a zeaxanthin-enriched diet. Applying a genome wide microarray analysis, we assessed the effects of the parent carotenoids on the liver transcriptome. Our analysis documented changes in pathways for liver lipid metabolism and mitochondrial respiration. We biochemically defined these effects, and observed that β-carotene accumulation resulted in an elevation of liver triglycerides and liver cholesterol, while zeaxanthin accumulation increased serum cholesterol levels. We further show that carotenoids were predominantly transported within HDL particles in the serum of mice. Finally, we provide evidence that carotenoid accumulation influenced whole-body respiration and energy expenditure. Thus, we observed that accumulation of parent carotenoids interacts with lipid metabolism and that structurally related carotenoids display distinct biological functions in mammals. PMID:27389691

The Influence of Epicardial Fat and Nonalcoholic Fatty Liver Disease on Heart Rate Recovery in Metabolic Syndrome.

Science.gov (United States)

Cho, Kyoung Im; Jo, Eun Ah; Cho, Sang Hoon; Kim, Bo Hyun

2017-06-01

Epicardial adipose tissues reflecting visceral fat accumulations of the heart are associated with metabolic syndrome (MetS) and can be a predictor of other cardiometabolic diseases. It can adversely influence autonomic nervous system (ANS) of heart. Heart rate recovery (HRR) is an easy method for measuring ANS dysfunction. The purpose of this study was to determine whether epicardial fat thickness (EFT) and nonalcoholic fatty liver disease (NAFLD) are related to HRR in patients with MetS. We enrolled 772 consecutive patients from a health-screening center who underwent abdominal ultrasonography, treadmill test, and cardiac echocardiography. EFT using echocardiography and HRR by symptom-limited exercise testing was assessed. According to the presence of MetS and NAFLD, patients were classified into the four groups. In NAFLD patients, EFT was higher and HRR was lower, especially in patients with MetS and NAFLD, compared to non-MetS participants without NAFLD (MetS with NAFLD, EFT 7.5 ± 4.4 mm, HRR 31.9 ± 12.7; MetS without NAFLD, EFT 4.9 ± 3.0 mm, HRR 39.5 ± 11.1; non-MetS with NAFLD, EFT 5.9 ± 3.6 mm, HRR 36.6 ± 12.7; and non-MetS without NAFLD, EFT 4.4 ± 3.5 mm, HRR 43.4 ± 14.5, p < 0.001). Patients with severe liver steatosis (LS) showed significantly higher EFT than those with moderate LS (14.2 ± 2.0 vs. 7.5 ± 3.1 mm, P < 0.001), and EFT was positively correlated with severity of LS (r = 0.431, P < 0.001). HRR was significantly correlated with EFT (r = -0.386, P < 0.001) and severity of LS (r = -0.324, P < 0.001). EFT and NAFLD were significantly correlated with HRR in patients with MetS and they may be highly related to increased cardiovascular risk. These results suggest a cross-link among EFT, NAFLD, and cardiac autonomic dysfunction in patients with MetS.

In vitro biotransformation rates in fish liver S9: effect of dosing techniques.

Science.gov (United States)

Lee, Yung-Shan; Lee, Danny H Y; Delafoulhouze, Maximilien; Otton, S Victoria; Moore, Margo M; Kennedy, Chris J; Gobas, Frank A P C

2014-08-01

In vitro biotransformation assays are currently being explored to improve estimates of bioconcentration factors of potentially bioaccumulative organic chemicals in fish. The present study compares thin-film and solvent-delivery dosing techniques as well as single versus multiple chemical dosing for measuring biotransformation rates of selected polycyclic aromatic hydrocarbons in rainbow trout (Oncorhynchus mykiss) liver S9. The findings show that biotransformation rates of very hydrophobic substances can be accurately measured in thin-film sorbent-dosing assays from concentration-time profiles in the incubation medium but not from those in the sorbent phase because of low chemical film-to-incubation-medium mass-transfer rates at the incubation temperature of 13.5 °C required for trout liver assays. Biotransformation rates determined by thin-film dosing were greater than those determined by solvent-delivery dosing for chrysene (octanol-water partition coefficient [KOW ] =10(5.60) ) and benzo[a]pyrene (KOW  =10(6.04) ), whereas there were no statistical differences in pyrene (KOW  =10(5.18) ) biotransformation rates between the 2 methods. In sorbent delivery-based assays, simultaneous multiple-chemical dosing produced biotransformation rates that were not statistically different from those measured in single-chemical dosing experiments for pyrene and benzo[a]pyrene but not for chrysene. In solvent-delivery experiments, multiple-chemical dosing produced biotransformation rates that were much smaller than those in single-chemical dosing experiments for all test chemicals. While thin-film sorbent-phase and solvent delivery-based dosing methods are both suitable methods for measuring biotransformation rates of substances of intermediate hydrophobicity, thin-film sorbent-phase dosing may be more suitable for superhydrophobic chemicals. © 2014 SETAC.

An Overview of Novel Dietary Supplements and Food Ingredients in Patients with Metabolic Syndrome and Non-Alcoholic Fatty Liver Disease

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Priscila Silva Figueiredo

2018-04-01

Full Text Available Metabolic syndrome (MetS is characterized by interconnected factors related to metabolic disturbances, and is directly related to the occurrence of some diseases such as cardiovascular diseases and type 2 diabetes. MetS is described as one or both of insulin resistance and visceral adiposity, considered the initial causes of abnormalities that include hyperglycemia, elevated blood pressure, dyslipidemia, elevated inflammatory markers, and prothrombotic state, as well as polycystic ovarian syndrome in women. Other than in MetS, visceral adiposity and the pro-inflammatory state are also key in the development of non-alcoholic fatty liver disease (NAFLD, which is the most prevalent chronic liver disease in modern society. Both MetS and NAFLD are related to diet and lifestyle, and their treatment may be influenced by dietary pattern changes and the use of certain dietary supplements. This study aimed to review the role of food ingredients and supplements in the management of MetS and NAFLD specifically in human clinical trials. Moreover, bioactive compounds and polyunsaturated fatty acids (PUFAs may be used as strategies for preventing the onset of and treatment of metabolic disorders, such as MetS and NAFLD, improving the inflammatory state and other comorbidities, such as obesity, dyslipidemias, and cardiovascular diseases (CVD.

Evolving insights on metabolism, autophagy and epigenetics in liver myofibroblasts

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Zeribe Chike Nwosu

2016-06-01

Full Text Available Liver myofibroblasts (MFB are crucial mediators of extracellular matrix (ECM deposition in liver fibrosis. They arise mainly from hepatic stellate cells (HSCs upon a process termed activation. To a lesser extent, and depending on the cause of liver damage, portal fibroblasts, mesothelial cells and fibrocytes may also contribute to the MFB population. Targeting MFB to reduce liver fibrosis is currently an area of intense research. Unfortunately, a clog in the wheel of antifibrotic therapies is the fact that although MFB are known to mediate scar formation, and participate in liver inflammatory response, many of their molecular portraits are currently unknown. In this review, we discuss recent understanding of MFB in health and diseases, focusing specifically on three evolving research fields: metabolism, autophagy and epigenetics. We have emphasized on therapeutic prospects where applicable and mentioned techniques for use in MFB studies. Subsequently, we highlighted uncharted territories in MFB research to help direct future efforts aimed at bridging gaps in current knowledge.

Effect of phenobarbital pretreatment on benzene biotransformation in the rat. Pt. 2. 9. 000 g supernatant and isolated perfused liver versus living rat

Energy Technology Data Exchange (ETDEWEB)

Gut, I.; Hatle, K.; Zizkova, L.

1981-03-01

Factors responsible for different quantitative effect of phenobarbital (PB) pretreatment on benzene metabolism to phenol in vivo and in vitro were studied in male Wistar rats. A more than 4-fold increase of benzene metabolism was observed with 9,000 g supernatant of liver homogenate, 2.8- to 4-fold increase with isolated perfused liver; phenol formation in vivo after oral benzene was increased by PB 2-fold, but only shortly following benzene administration and the enhancement rapidly diminished to 1.15-fold increase in the total excreted phenol. Benzene concentrations in 9,000 g supernatant incubations were 2 mM, those with isolated perfused livers were up to 4 mM, but those in blood in vivo were below 0.3 mM; the effect of PB induction in vivo disappeared along with decreasing benzene and increasing phenol blood concentrations which surpassed benzene 2-3 h after oral benzene administration. The effect of benzene concentration on the manifestation of PB induction is also supported by almost a 2-fold increased phenol formation in PB rats over controls in vivo after repeated administration of benzene. The elimination of radioactive metabolites of orally administered benzene-/sup 14/C, in urine was markedly inhibited by intraperitoneal administration of phenol, but not by pyrocatechol, resorcinol or hydroquinol suggesting that phenol might inhibit benzene metabolism in vivo especially when its concentration exceeds that of benzene.

Non-alcoholic fatty liver disease and metabolic syndrome in Brazilian middle-aged and older adults

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Mauro Karnikowski

Full Text Available CONTEXT AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD is a complex clinicopathological entity characterized by diffuse or focal fat accumulation in the hepatic parenchyma of patients who deny abusive alcohol consumption. This study aimed to assess idiopathic NAFLD in community-dwelling, middle-aged and older adults living in the Brazilian Federal District. Associations between NAFLD and components of metabolic syndrome and the whole syndrome were investigated. DESIGN AND SETTINGS: This was a cross-sectional study on 139 subjects aged 55 years or older. METHODS: NAFLD was diagnosed by means of clinical procedures, to exclude subjects with signs of liver disorders, abusive alcohol consumption and influence from hepatotoxic drugs. Phenotypes were graded based on ultrasound examination. Metabolic syndrome was defined using the NCEP ATP III criteria. Laboratory tests were performed to assist clinical examinations and define the syndrome. RESULTS NAFLD was present in 35.2% of the subjects. Taken together, the two most intense phenotypes correlated with increased serum fasting glucose, triglyceride and VLDL cholesterol levels. Metabolic syndrome was diagnosed in 25.9% of the sample. In addition to associating NAFLD with specific traits of metabolic syndrome, non-parametric analysis confirmed the existence of a relationship (p < 0.05 between the steatotic manifestation and the syndromic condition. CONCLUSION: Compared with the literature, this study reveals greater frequency of idiopathic NAFLD among Brazilian middle-aged and older adults than is described elsewhere. The findings also suggest that impaired glycemic metabolism coupled with increased fat delivery and/or sustained endogenous biosynthesis is the most likely physiopathogenic mechanisms underlying the onset of NAFLD in this population.

Tocotrienols Reverse Cardiovascular, Metabolic and Liver Changes in High Carbohydrate, High Fat Diet-Fed Rats

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Weng-Yew Wong

2012-10-01

Full Text Available Tocotrienols have been reported to improve lipid profiles, reduce atherosclerotic lesions, decrease blood glucose and glycated haemoglobin concentrations, normalise blood pressure in vivo and inhibit adipogenesis in vitro, yet their role in the metabolic syndrome has not been investigated. In this study, we investigated the effects of palm tocotrienol-rich fraction (TRF on high carbohydrate, high fat diet-induced metabolic, cardiovascular and liver dysfunction in rats. Rats fed a high carbohydrate, high fat diet for 16 weeks developed abdominal obesity, hypertension, impaired glucose and insulin tolerance with increased ventricular stiffness, lower systolic function and reduced liver function. TRF treatment improved ventricular function, attenuated cardiac stiffness and hypertension, and improved glucose and insulin tolerance, with reduced left ventricular collagen deposition and inflammatory cell infiltration. TRF improved liver structure and function with reduced plasma liver enzymes, inflammatory cell infiltration, fat vacuoles and balloon hepatocytes. TRF reduced plasma free fatty acid and triglyceride concentrations but only omental fat deposition was decreased in the abdomen. These results suggest that tocotrienols protect the heart and liver, and improve plasma glucose and lipid profiles with minimal changes in abdominal obesity in this model of human metabolic syndrome.

Putrescine treatment reverses α-tocopherol-induced desynchronization of polyamine and retinoid metabolism during rat liver regeneration

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Lourdes Sánchez-Sevilla

2016-10-01

Full Text Available Abstract Background The pre-treatment with α-tocopherol inhibits progression of rat liver proliferation induced by partial hepatectomy (PH, by decreasing and/or desynchronizing cyclin D1 expression and activation into the nucleus, activation and nuclear translocation of STAT-1 and -3 proteins and altering retinoid metabolism. Interactions between retinoic acid and polyamines have been reported in the PH-induced rat liver regeneration. Therefore, we evaluated the effect of low dosage of α-tocopherol on PH-induced changes in polyamine metabolism. Methods This study evaluated the participation of polyamine synthesis and metabolism during α-tocopherol-induced inhibition of rat liver regeneration. In PH-rats (Wistar treated with α-tocopherol and putrescine, parameters indicative of cell proliferation, lipid peroxidation, ornithine decarboxylase expression (ODC, and polyamine levels, were determined. Results Pre-treatment with α-tocopherol to PH-animals exerted an antioxidant effect, shifting earlier the increased ODC activity and expression, temporally affecting polyamine synthesis and ornithine metabolism. Whereas administration of putrescine induced minor changes in PH-rats, the concomitant treatment actually counteracted most of adverse actions exerted by α-tocopherol on the remnant liver, restituting its proliferative potential, without changing its antioxidant effect. Putrescine administration to these rats was also associated with lower ODC expression and activity in the proliferating liver, but the temporally shifting in the amount of liver polyamines induced by α-tocopherol, was also “synchronized” by the putrescine administration. The latter is supported by the fact that a close relationship was observed between fluctuations of polyamines and retinoids. Conclusions Putrescine counteracted most adverse actions exerted by α-tocopherol on rat liver regeneration, restoring liver proliferative potential and restituting the decreased

The in utero programming effect of increased maternal androgens and a direct fetal intervention on liver and metabolic function in adult sheep.

Directory of Open Access Journals (Sweden)

Kirsten Hogg

Full Text Available Epigenetic changes in response to external stimuli are fast emerging as common underlying causes for the pre-disposition to adult disease. Prenatal androgenization is one such model that results in reproductive and metabolic features that are present in conditions such as polycystic ovary syndrome (PCOS. We examined the effect of prenatal androgens on liver function and metabolism of adult sheep. As non-alcoholic fatty liver disease is increased in PCOS we hypothesized that this, and other important liver pathways including metabolic function, insulin-like growth factor (IGF and steroid receptivity, would be affected. Pregnant ewes received vehicle control (C; n = 5 or testosterone propionate (TP; n = 9 twice weekly (100 mg; i.m from d62-102 (gestation 147 days. In a novel treatment paradigm, a second cohort received a direct C (n = 4 or TP (20 mg; n = 7 fetal injection at d62 and d82. In adults, maternal TP exposure resulted in increased insulin secretion to glucose load (P<0.05 and the histological presence of fatty liver (P<0.05 independent of central obesity. Additionally, hepatic androgen receptor (AR; P<0.05, glucocorticoid receptor (GR; P<0.05, UDP- glucose ceramide glucosyltransferase (UGCG; P<0.05 and IGF1 (P<0.01 expression were upregulated. The direct fetal intervention (C and TP led to early fatty liver changes in all animals without differential changes in insulin secretion. Furthermore, hepatic phosphoenolpyruvate carboxykinase (PEPCK was up-regulated in the fetal controls (P<0.05 and this was opposed by fetal TP (P<0.05. Hepatic estrogen receptor (ERα; P<0.05 and mitogen activated protein kinase kinase 4 (MAP2K4; P<0.05 were increased following fetal TP exposure. Adult liver metabolism and signaling can be altered by early exposure to sex steroids implicating epigenetic regulation of metabolic disturbances that are common in PCOS.

Metabolic profiling of fatty liver in young and middle‐aged adults: Cross‐sectional and prospective analyses of the Young Finns Study

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Würtz, Peter; Suomela, Emmi; Lehtovirta, Miia; Kangas, Antti J.; Jula, Antti; Mikkilä, Vera; Viikari, Jorma S.A.; Juonala, Markus; Rönnemaa, Tapani; Hutri‐Kähönen, Nina; Kähönen, Mika; Lehtimäki, Terho; Soininen, Pasi; Ala‐Korpela, Mika; Raitakari, Olli T.

2016-01-01

Nonalcoholic fatty liver is associated with obesity‐related metabolic disturbances, but little is known about the metabolic perturbations preceding fatty liver disease. We performed comprehensive metabolic profiling to assess how circulating metabolites, such as lipoprotein lipids, fatty acids, amino acids, and glycolysis‐related metabolites, reflect the presence of and future risk for fatty liver in young adults. Sixty‐eight lipids and metabolites were quantified by nuclear magnetic resonance metabolomics in the population‐based Young Finns Study from serum collected in 2001 (n = 1,575), 2007 (n = 1,509), and 2011 (n = 2,002). Fatty liver was diagnosed by ultrasound in 2011 when participants were aged 34‐49 years (19% prevalence). Cross‐sectional associations as well as 4‐year and 10‐year risks for fatty liver were assessed by logistic regression. Metabolites across multiple pathways were strongly associated with the presence of fatty liver (P fatty acids including omega‐6 (OR = 0.37, 0.32‐0.42). The metabolic associations were attenuated but remained significant after adjusting for waist, physical activity, alcohol consumption, and smoking (P fatty liver diagnosis. Conclusion: Circulating lipids, fatty acids, and amino acids reflect fatty liver independently of routine metabolic risk factors; these metabolic aberrations appear to precede the development of fatty liver in young adults. (Hepatology 2017;65:491‐500). PMID:27775848

Maternal obesity disrupts circadian rhythms of clock and metabolic genes in the offspring heart and liver.

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Wang, Danfeng; Chen, Siyu; Liu, Mei; Liu, Chang

2015-06-01

Early life nutritional adversity is tightly associated with the development of long-term metabolic disorders. Particularly, maternal obesity and high-fat diets cause high risk of obesity in the offspring. Those offspring are also prone to develop hyperinsulinemia, hepatic steatosis and cardiovascular diseases. However, the precise underlying mechanisms leading to these metabolic dysregulation in the offspring remain unclear. On the other hand, disruptions of diurnal circadian rhythms are known to impair metabolic homeostasis in various tissues including the heart and liver. Therefore, we investigated that whether maternal obesity perturbs the circadian expression rhythms of clock, metabolic and inflammatory genes in offspring heart and liver by using RT-qPCR and Western blotting analysis. Offspring from lean and obese dams were examined on postnatal day 17 and 35, when pups were nursed by their mothers or took food independently. On P17, genes examined in the heart either showed anti-phase oscillations (Cpt1b, Pparα, Per2) or had greater oscillation amplitudes (Bmal1, Tnf-α, Il-6). Such phase abnormalities of these genes were improved on P35, while defects in amplitudes still existed. In the liver of 17-day-old pups exposed to maternal obesity, the oscillation amplitudes of most rhythmic genes examined (except Bmal1) were strongly suppressed. On P35, the oscillations of circadian and inflammatory genes became more robust in the liver, while metabolic genes were still kept non-rhythmic. Maternal obesity also had a profound influence in the protein expression levels of examined genes in offspring heart and liver. Our observations indicate that the circadian clock undergoes nutritional programing, which may contribute to the alternations in energy metabolism associated with the development of metabolic disorders in early life and adulthood.

A tryptophan derivative, ITE, enhances liver cell metabolic functions in vitro.

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Zhang, Xiaoqian; Lu, Juan; He, Bin; Tang, Lingling; Liu, Xiaoli; Zhu, Danhua; Cao, Hongcui; Wang, Yingjie; Li, Lanjuan

2017-01-01

Cell encapsulation provides a three-dimensional support by incorporating isolated cells into microcapsules with the goal of simultaneously maintaining cell survival and function, as well as providing active transport for a bioreactor in vitro similarly to that observed in vivo. However, the biotra-nsformation and metabolic functions of the encapsulated cells are not satisfactory for clinical applications. For this purpose, in this study, hepatoma-derived Huh7 cells/C3A cells were treated with 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE), an endogenous non-toxic ligand for aryl hydrocarbon receptor, in monolayer cultures and on microspheres. The mRNA and protein levels, as well as the metabolic activities of drug metabolizing enzymes, albumin secretion and urea synthesis were determined. When the Huh7 and C3A cells cultured in a monolayer on two‑dimensional surfaces, ITE enhanced the protein levels and the metabolic activities of the major cytochrome P450 (CYP450) enzymes, CYP1A1, CYP1A2, CYP3A4 and CYP1B1, and slightly increased albumin secretion and urea synthesis. Moreover, when cultured on microspheres, ITE also substantially increased the protein levels and metabolic activities of CYP1A1, CYP1A2, CYP3A4 and CYP1B1 in both liver cell lines. On the whole, our findings indicate that ITE enhances the enzymatic activities of major CYP450 enzymes and the metabolic functions of liver cells cultured in monolayer or on microspheres, indicating that it may be utilized to improve the functions of hepatocytes. Thus, it may be used in the future for the treatment of liver diseases.

Dietary pattern associated with selenoprotein P and MRI-derived body fat volumes, liver signal intensity, and metabolic disorders.

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di Giuseppe, Romina; Plachta-Danielzik, Sandra; Koch, Manja; Nöthlings, Ute; Schlesinger, Sabrina; Borggrefe, Jan; Both, Marcus; Müller, Hans-Peter; Kassubek, Jan; Jacobs, Gunnar; Lieb, Wolfgang

2018-02-14

The association of complex dietary patterns with circulating selenoprotein P (SELENOP) levels in humans is unknown. In a general population sample, we aimed to identify a dietary pattern explaining inter-individual variation in circulating SELENOP concentrations and to study this pattern in relation to prevalent diabetes, metabolic syndrome (MetS), MRI-determined total volumes of visceral (VAT) and subcutaneous (SAT) abdominal adipose tissue, and liver signal intensity/fatty liver disease. In this cross-sectional study, serum SELENOP levels were measured in 853 individuals. In a subsample of 553 participants, whole-body MRI was performed to assess body fat distribution and liver fat. Dietary intake was assessed by a self-administered food frequency questionnaire and the dietary pattern identified using reduced-rank regression (RRR). Multivariable linear and logistic regressions were used to investigate associations between dietary pattern score and metabolic traits. Characterized by high intake of fruit, vegetables and antioxidant beverages, the RRR-derived dietary pattern displayed inverse associations with VAT, SAT, MetS, and prevalent diabetes in multivariable-adjusted restricted cubic splines. Each unit increase in dietary pattern score was associated with 31% higher SELENOP levels, 12% lower VAT (95% CI: - 19%; - 5%), 13% (95% CI: - 20%; - 6%) lower SAT values and 46% (95% CI: 27%; 60%) and 53% (95% CI: 22%; 72%) lower odds of having MetS or diabetes, respectively. No meaningful relations were observed between the dietary pattern and liver traits. Our observations propose diet-related regulation in SELENOP levels and that the identified dietary pattern is inversely related to VAT, SAT, MetS, and prevalent diabetes.

Effects of acupuncture on the citrate and glucose metabolism in the liver under various types of stress

International Nuclear Information System (INIS)

Liao, Y.Y.; Seto, K.; Saito, H.; Kawakami, M.

1980-01-01

A study was made of the effect of acupuncture on citrate and glucose metabolism in the liver in terms of incorporation of 14 C-1, 5-citric acid and 14 C-u-glucose in some metabolites. The effect of acupuncture on citrate metabolism in the liver under control conditions was such as to increase production of G and reduce that of KB, FC and FFA. No effect of acupuncture on glucose metabolism in the liver under such conditions was observed. Both citrate and glucose metabolism were affected to a marked extent by immobilization stress or exposure to heat or cold. The deleterious effect of these types of stress was less prominent in animals receiving acupuncture at the Tsu-San-Li locus than in those treated otherwise or receiving no treatment

Effects of acupuncture on the citrate and glucose metabolism in the liver under various types of stress

Energy Technology Data Exchange (ETDEWEB)

Liao, Y.Y.; Seto, K.; Saito, H.; Kawakami, M.

A study was made of the effect of acupuncture on citrate and glucose metabolism in the liver in terms of incorporation of /sup 14/C-1, 5-citric acid and /sup 14/C-u-glucose in some metabolites. The effect of acupuncture on citrate metabolism in the liver under control conditions was such as to increase production of G and reduce that of KB, FC and FFA. No effect of acupuncture on glucose metabolism in the liver under such conditions was observed. Both citrate and glucose metabolism were affected to a marked extent by immobilization stress or exposure to heat or cold. The deleterious effect of these types of stress was less prominent in animals receiving acupuncture at the Tsu-San-Li locus than in those treated otherwise or receiving no treatment.

Relationship between obesity, metabolic syndrome, and nonalcoholic fatty liver disease in the elderly agricultural and fishing population of Taiwan.

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Shen, Hsi-Che; Zhao, Zi-Hao; Hu, Yi-Chun; Chen, Yu-Fen; Tung, Tao-Hsin

2014-01-01

The purpose of this study was to explore the relationship between obesity, the metabolic syndrome, and nonalcoholic fatty liver disease (NAFLD) in the elderly agricultural and fishing population of Taipei, Taiwan. The study participants comprised 6,511 (3,971 male and 2,540 female) healthy elderly subjects voluntarily attending a teaching hospital for a physical check-up in 2010. Blood samples and real-time ultrasound-proven fatty liver sonography results were collected. The prevalence of NAFLD in this elderly population was 27.2%, including mild NAFLD (16.0%), moderate NAFLD (10.3%), and severe NAFLD (0.9%). The prevalence of moderate or severe NAFLD for metabolic syndrome proved to be substantially greater (P<0.0001, χ(2) test) for one or two metabolic factors. Using multinomial logistic regression analysis, age, sex, metabolic syndrome, and higher body mass index had a statistically significant association with mild NAFLD. Age, sex, metabolic syndrome, higher body mass index, and higher alanine aminotransferase were significantly related to moderate NAFLD. In addition, higher body mass index, higher uric acid, and higher alanine aminotransferase levels were significantly related to severe NAFLD. The sensitivity and specificity of body mass index and waist circumference as markers of NAFLD were estimated to be 81% and 84%, respectively, and 77% and 69%, respectively. The prevalence of mild or moderate NAFLD was related to obesity and metabolic syndrome. Higher body mass index was also related to severe NAFLD but not to metabolic syndrome. Targeting this population for control of obesity and improved metabolic function is important.

Non-alcoholic fatty liver disease and subclinical atherosclerosis: A comparison of metabolically- versus genetically-driven excess fat hepatic storage.

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Di Costanzo, Alessia; D'Erasmo, Laura; Polimeni, Licia; Baratta, Francesco; Coletta, Paola; Di Martino, Michele; Loffredo, Lorenzo; Perri, Ludovica; Ceci, Fabrizio; Montali, Anna; Girelli, Gabriella; De Masi, Bruna; Angeloni, Antonio; Catalano, Carlo; Maranghi, Marianna; Del Ben, Maria; Angelico, Francesco; Arca, Marcello

2017-02-01

Non-alcoholic fatty liver disease (NAFLD) is frequently associated with atherosclerosis. However, it is unclear whether this association is related to excess fat liver storage per se or to metabolic abnormalities that typically accompany NAFLD. To investigate this, we compared individuals with hepatic steatosis driven by metabolic disturbances to those with hepatic steatosis associated with the rs738409 GG genotype in the patatin-like phospholipase domain-containing 3 gene (PNPLA3). Carotid intima-media thickness (CIMT), as a surrogate marker of subclinical atherosclerosis, was measured in 83 blood donors with the mutant GG genotype (group G), 100 patients with features of metabolic syndrome (MetS) but the wildtype CC genotype (group M), and 74 blood donors with the wildtype CC genotype (controls). Fatty liver was evaluated by ultrasonography and hepatic fat fraction (HFF) was measured using magnetic resonance (MRS/MRI) in 157 subjects. Compared with group G and controls, group M subjects were older and had increased adiposity indices, dyslipidemia, insulin resistance and elevated transaminase levels (all p hepatic steatosis), the median CIMT in group M (0.84 [0.70-0.95] mm) was significantly greater than that in group G (0.66 [0.55-0.74] mm; p < 0.001), which was similar to that in controls (0.70 [0.64-0.81] mm). Results were similar in the subgroup evaluated using MRS/MRI. Excess liver fat accumulation appeared to increase the burden of subclinical atherosclerosis only when it is associated with metabolic abnormalities. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Effect of CAR activation on selected metabolic pathways in normal and hyperlipidemic mouse livers.

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Rezen, Tadeja; Tamasi, Viola; Lövgren-Sandblom, Anita; Björkhem, Ingemar; Meyer, Urs A; Rozman, Damjana

2009-08-19

Detoxification in the liver involves activation of nuclear receptors, such as the constitutive androstane receptor (CAR), which regulate downstream genes of xenobiotic metabolism. Frequently, the metabolism of endobiotics is also modulated, resulting in potentially harmful effects. We therefore used 1,4-Bis [2-(3,5-dichloropyridyloxy)] benzene (TCPOBOP) to study the effect of CAR activation on mouse hepatic transcriptome and lipid metabolome under conditions of diet-induced hyperlipidemia. Using gene expression profiling with a dedicated microarray, we show that xenobiotic metabolism, PPARalpha and adipocytokine signaling, and steroid synthesis are the pathways most affected by TCPOBOP in normal and hyperlipidemic mice. TCPOBOP-induced CAR activation prevented the increased hepatic and serum cholesterol caused by feeding mice a diet containing 1% cholesterol. We show that this is due to increased bile acid metabolism and up-regulated removal of LDL, even though TCPOBOP increased cholesterol synthesis under conditions of hyperlipidemia. Up-regulation of cholesterol synthesis was not accompanied by an increase in mature SREBP2 protein. As determined by studies in CAR -/- mice, up-regulation of cholesterol synthesis is however CAR-dependent; and no obvious CAR binding sites were detected in promoters of cholesterogenic genes. TCPOBOP also affected serum glucose and triglyceride levels and other metabolic processes in the liver, irrespective of the diet. Our data show that CAR activation modulates hepatic metabolism by lowering cholesterol and glucose levels, through effects on PPARalpha and adiponectin signaling pathways, and by compromising liver adaptations to hyperlipidemia.

Liver carbohydrates metabolism: A new islet-neogenesis associated protein peptide (INGAP-PP) target.

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Villagarcía, Hernán Gonzalo; Román, Carolina Lisi; Castro, María Cecilia; González, Luisa Arbeláez; Ronco, María Teresa; Francés, Daniel Eleazar; Massa, María Laura; Maiztegui, Bárbara; Flores, Luis Emilio; Gagliardino, Juan José; Francini, Flavio

2018-03-01

Islet-Neogenesis Associated Protein-Pentadecapeptide (INGAP-PP) increases β-cell mass and enhances glucose and amino acids-induced insulin secretion. Our aim was to demonstrate its effect on liver metabolism. For that purpose, adult male Wistar rats were injected twice-daily (10 days) with saline solution or INGAP-PP (250 μg). Thereafter, serum glucose, triglyceride and insulin levels were measured and homeostasis model assessment (HOMA-IR) and hepatic insulin sensitivity (HIS) were determined. Liver glucokinase and glucose-6-phosphatase (G-6-Pase) expression and activity, phosphoenolpyruvate carboxykinase (PEPCK) expression, phosphofructokinase-2 (PFK-2) protein content, P-Akt/Akt and glycogen synthase kinase-3β (P-GSK3/GSK3) protein ratios and glycogen deposit were also determined. Additionally, glucokinase activity and G-6-Pase and PEPCK gene expression were also determined in isolated hepatocytes from normal rats incubated with INGAP-PP (5 μg/ml). INGAP-PP administration did not modify any of the serum parameters tested but significantly increased activity of liver glucokinase and the protein level of its cytosolic activator, PFK-2. Conversely, INGAP-PP treated rats decreased gene expression and enzyme activity of gluconeogenic enzymes, G-6-Pase and PEPCK. They also showed a higher glycogen deposit and P-GSK3/GSK3 and P-Akt/Akt ratio. In isolated hepatocytes, INGAP-PP increased GK activity and decreased G-6-Pase and PEPCK expression. These results demonstrate a direct effect of INGAP-PP on the liver acting through P-Akt signaling pathway. INGAP-PP enhances liver glucose metabolism and deposit and reduces its production/output, thereby contributing to maintain normal glucose homeostasis. These results reinforce the concept that INGAP-PP might become a useful tool to treat people with impaired islet/liver glucose metabolism as it occurs in T2D. Copyright © 2018 Elsevier Inc. All rights reserved.

The metabolic effects of diuron in the rat liver.

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da Silva Simões, Mellina; Bracht, Lívia; Parizotto, Angela Valderrama; Comar, Jurandir Fernando; Peralta, Rosane Marina; Bracht, Adelar

2017-09-01

A systematic study on the effects of diuron on the hepatic metabolism was conducted with emphasis on parameters linked to energy metabolism. The experimental system was the isolated perfused rat liver. The results demonstrate that diuron inhibited biosynthesis (gluconeogenesis) and ammonia detoxification, which are dependent of ATP generated within the mitochondria. Conversely, it stimulated glycolysis and fructolysis, which are compensatory phenomena for an inhibited mitochondrial ATP generation. Furthermore, diuron diminished the cellular ATP content under conditions where the mitochondrial respiratory chain was the only source of this compound. Besides the lack of circulating glucose due to gluconeogenesis inhibition, one can expect metabolic acidosis due to excess lactate production, impairment of ammonia detoxification and cell damage due to a deficient maintenance of its homeostasis. Some of the general signs of toxicity that were observed in diuron-treated rats can be attributed, partly at least, to the effects of the herbicide on energy metabolism. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of naphthenic acid exposure on development and liver metabolic processes in anuran tadpoles

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Melvin, Steven D.; Lanctôt, Chantal M.; Craig, Paul M.; Moon, Thomas W.; Peru, Kerry M.; Headley, John V.; Trudeau, Vance L.

2013-01-01

Naphthenic acids (NA) are used in a variety of commercial and industrial applications, and are primary toxic components of oil sands wastewater. We investigated developmental and metabolic responses of tadpoles exposed to sub-lethal concentrations of a commercial NA blend throughout development. We exposed Lithobates pipiens tadpoles to 1 and 2 mg/L NA for 75 days and monitored growth and development, condition factor, gonad and liver sizes, and levels of liver glucose, glycogen, lipids and cholesterol following exposure. NA decreased growth and development, significantly reduced glycogen stores and increased triglycerides, indicating disruption to processes associated with energy metabolism and hepatic glycolysis. Effects on liver function may explain reduced growth and delayed development observed in this and previous studies. Our data highlight the need for greater understanding of the mechanisms leading to hepatotoxicity in NA-exposed organisms, and indicate that strict guidelines may be needed for the release of NA into aquatic environments. -- Highlights: ► We exposed Lithobates pipiens tadpoles to 1–2 mg/L NA in the laboratory. ► We monitored survival, growth and development for 75 days. ► We measured liver glycogen, glucose, triglycerides, and cholesterol levels. ► NA significantly reduced growth and development compared to controls. ► NA significantly reduced glycogen levels and increased triglycerides. -- Leopard frog (Lithobates pipiens) tadpoles chronically exposed to sub-lethal NA concentrations (1–2 mg/L) suffered decreased growth and development and disruption to liver metabolic processes

Citrate Defines a Regulatory Link Between Energy Metabolism and the Liver Hormone Hepcidin

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Ladeira Courelas da Silva, Ana Rita

2017-01-01

Iron plays a critical role as an oxygen carrier in hemoglobin as well as a constituent of iron-sulfur clusters. Increasing evidence suggests that mechanisms maintaining iron homeostasis cross-talk to intermediary metabolism. The liver hormone hepcidin is the key regulator of systemic iron metabolism. Hepcidin transcriptional control is linked to the nutrient-sensing mTOR pathway, proliferative signals, gluconeogenic responses during starvation and hormones that modulate energy metabolism. The...

Metabolic Profiling of Liver Tissue in Diabetic Mice Treated with Artemisia Capillaris and Alisma Rhizome Using LC-MS and CE-MS.

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Kim, Yumi; Lee, In-Seung; Kim, Kang-Hoon; Park, Jiyoung; Lee, Ji-Hyun; Bang, Eunjung; Jang, Hyeung-Jin; Na, Yun-Cheol

2016-01-01

Artemisia Capillaris (AC) and Alisma Rhizome (AR) are natural products for the treatment of liver disorders in oriental medicine clinics. Here, we report metabolomic changes in the evaluation of the treatment effects of AC and AR on fatty livers in diabetic mice, along with a proposition of the underlying metabolic pathway. Hydrophobic and hydrophilic metabolites extracted from mouse livers were analyzed using HPLC-QTOF and CE-QTOF, respectively, to generate metabolic profiles. Statistical analysis of the metabolites by PLS-DA and OPLA-DA fairly discriminated between the diabetic, and the AC- and AR-treated mice groups. Various PEs mostly contributed to the discrimination of the diabetic mice from the normal mice, and besides, DG (18:1/16:0), TG (16:1/16:1/20:1), PE (21:0/20:5), and PA (18:0/21:0) were also associated with discrimination by s-plot. Nevertheless, the effects of AC and AR treatment were indistinct with respect to lipid metabolites. Of the 97 polar metabolites extracted from the CE-MS data, 40 compounds related to amino acid, central carbon, lipid, purine, and pyrimidine metabolism, with [Formula: see text] values less than 0.05, were shown to contribute to liver dysregulation. Following treatment with AC and AR, the metabolites belonging to purine metabolism preferentially recovered to the metabolic state of the normal mice. The AMP/ATP ratio of cellular energy homeostasis in AR-treated mice was more apparently increased ([Formula: see text]) than that of AC-treated mice. On the other hand, amino acids, which showed the main alterations in diabetic mice, did not return to the normal levels upon treatment with AR or AC. In terms of metabolomics, AR was a more effective natural product in the treatment of liver dysfunction than AC. These results may provide putative biomarkers for the prognosis of fatty liver disorder following treatment with AC and AR extracts.

Metabolism of S-adenosylmethionine in rat hepatocytes: transfer of methyl group from S-adenosylmethionine by methyltransferase reactions

International Nuclear Information System (INIS)

Tsukada, K.; Abe, T.; Kuwahata, T.; Mitsui, K.

1985-01-01

Treatment of rats with a methionine diet leads not only to a marked increase of S-adenosylmethionine synthetase in liver, but also to the increase of glycine, guanidoacetate and betaine-homocysteine methyltransferases. The activity of tRNA methyltransferase decreased with the increased amounts of methionine in the diets. However, the activities of phospholipids and S-adenosylmethionine-homocysteine methyltransferases did not show any significant change. When hepatocarcinogenesis induced by 2-fluorenylacetamide progresses, the activities of glycine and guanidoacetate methyltransferases in rat liver decreased, and could not be detected in tumorous areas 8 months after treatment. The levels of S-adenosylmethionine in the liver also decreased to levels of one-fifth of control animals at 8 months. The uptake and metabolism of [methyl- 3 H]-methionine and -S-adenosylmethionine have been investigated by in vivo and isolated hepatocytes. The uptake of methionine and transfer of methyl group to phospholipid in the cells by methionine were remarkably higher than those by S-adenosylmethionine. These results indicate that phospholipids in hepatocytes accept methyl group from S-adenosylmethionine immediately, when it is synthesized from methionine, before mixing its pool in the cells. 39 references, 1 figure, 2 tables

Coenzyme Q Metabolism Is Disturbed in High Fat Diet-Induced Non Alcoholic Fatty Liver Disease in Rats

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Kathleen M Botham

2012-02-01

Full Text Available Oxidative stress is believed to be a major contributory factor in the development of non alcoholic fatty liver disease (NAFLD, the most common liver disorder worldwide. In this study, the effects of high fat diet-induced NAFLD on Coenzyme Q (CoQ metabolism and plasma oxidative stress markers in rats were investigated. Rats were fed a standard low fat diet (control or a high fat diet (57% metabolizable energy as fat for 18 weeks. The concentrations of total (reduced + oxidized CoQ9 were increased by > 2 fold in the plasma of animals fed the high fat diet, while those of total CoQ10 were unchanged. Reduced CoQ levels were raised, but oxidized CoQ levels were not, thus the proportion in the reduced form was increased by about 75%. A higher percentage of plasma CoQ9 as compared to CoQ10 was in the reduced form in both control and high fat fed rats. Plasma protein thiol (SH levels were decreased in the high fat-fed rats as compared to the control group, but concentrations of lipid hydroperoxides and low density lipoprotein (LDL conjugated dienes were unchanged. These results indicate that high fat diet-induced NAFLD in rats is associated with altered CoQ metabolism and increased protein, but not lipid, oxidative stress.

Identification of the Metabolic Enzyme Involved Morusin Metabolism and Characterization of Its Metabolites by Ultraperformance Liquid Chromatography Quadrupole Time-of-Flight Mass Spectrometry (UPLC/Q-TOF-MS/MS

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Xianbao Shi

2016-01-01

Full Text Available Morusin, the important active component of a traditional Chinese medicine, Morus alba L., has been shown to exhibit many vital pharmacological activities. In this study, six recombinant CYP450 supersomes and liver microsomes were used to perform metabolic studies. Chemical inhibition studies and screening assays with recombinant human cytochrome P450s were also used to characterize the CYP450 isoforms involved in morusin metabolism. The morusin metabolites identified varied greatly among different species. Eight metabolites of morusin were detected in the liver microsomes from pigs (PLMs, rats (RLMs, and monkeys (MLMs by LC-MS/MS and six metabolites were detected in the liver microsomes from humans (HLMs, rabbits (RAMs, and dogs (DLMs. Four metabolites (M1, M2, M5, and M7 were found in all species and hydroxylation was the major metabolic transformation. CYP1A2, CYP2C9, CYP2D6, CYP2E1, CYP3A4, and CYP2C19 contributed differently to the metabolism of morusin. Compared to other CYP450 isoforms, CYP3A4 played the most significant role in the metabolism of morusin in human liver microsomes. These results are significant to better understand the metabolic behaviors of morusin among various species.

Urinary Metabolomics in Pediatric Obesity and NAFLD Identifies Metabolic Pathways/Metabolites Related to Dietary Habits and Gut-Liver Axis Perturbations

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Jacopo Troisi

2017-05-01

Full Text Available To get insight into still elusive pathomechanisms of pediatric obesity and non-alcoholic fatty liver disease (NAFLD we explored the interplay among GC-MS studied urinary metabolomic signature, gut liver axis (GLA abnormalities, and food preferences (Kid-Med. Intestinal permeability (IP, small intestinal bacterial overgrowth (SIBO, and homeostatic model assessment-insulin resistance were investigated in forty children (mean age 9.8 years categorized as normal weight (NW or obese (body mass index <85th or >95th percentile, respectively ± ultrasonographic bright liver and hypertransaminasemia (NAFLD. SIBO was increased in all obese children (p = 0.0022, IP preferentially in those with NAFLD (p = 0.0002. The partial least-square discriminant analysis of urinary metabolome correctly allocated children based on their obesity, NAFLD, visceral fat, pathological IP and SIBO. Compared to NW, obese children had (1 higher levels of glucose/1-methylhistidine, the latter more markedly in NAFLD patients; and (2 lower levels of xylitol, phenyl acetic acid and hydroquinone, the latter especially in children without NAFLD. The metabolic pathways of BCAA and/or their metabolites correlated with excess of visceral fat centimeters (leucine/oxo-valerate, and more deranged IP and SIBO (valine metabolites. Urinary metabolome analysis contributes to define a metabolic fingerprint of pediatric obesity and related NAFLD, by identifying metabolic pathways/metabolites reflecting typical obesity dietary habits and GLA perturbations.

Rb and p53 Liver Functions Are Essential for Xenobiotic Metabolism and Tumor Suppression

NARCIS (Netherlands)

Nantasanti, Sathidpak; Toussaint, Mathilda J. M.; Youssef, Sameh A.; Tooten, Peter C. J.; de Bruin, Alain

2016-01-01

The tumor suppressors Retinoblastoma (Rb) and p53 are frequently inactivated in liver diseases, such as hepatocellular carcinomas (HCC) or infections with Hepatitis B or C viruses. Here, we discovered a novel role for Rb and p53 in xenobiotic metabolism, which represent a key function of the liver

Prevalence of Nonalcoholic Fatty Liver Disease in Normal-weight and Overweight Preadolescent Children in Haryana, India.

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Das, Manoja Kumar; Bhatia, Vidyut; Sibal, Anupam; Gupta, Abha; Gopalan, Sarath; Sardana, Raman; Sahni, Reeti; Roy, Ankur; Arora, Narendra K

2017-12-15

To document the prevalence of non-alcoholic fatty liver disease (NAFLD) and metabolic parameters among normal-weight and overweight schoolchildren. Cross-sectional study. Thirteen private schools in urban Faridabad, Haryana. 961 school children aged 5-10 years. Ultrasound testing was done, and 215 with fatty liver on ultrasound underwent further clinical, biochemical and virological testing. Prevalence of fatty liver on ultrasound, and NAFLD and its association with biochemical abnormalities and demographic risk factors. On ultrasound, 215 (22.4%) children had fatty liver; 18.9% in normal-weight and 45.6% in overweight category. Presence and severity of fatty liver disease increased with body mass index (BMI) and age. Among the children with NAFLD, elevated SGOT and SGPT was observed in 21.5% and 10.4% children, respectively. Liver enzyme derangement was significantly higher in overweight children (27% vs 19.4% in normal-weight) and severity of fatty liver (28% vs 20% in mild fatty liver cases). Eleven (8.1%) children with NAFLD had metabolic syndrome. Higher BMI (OR 35.9), severe fatty liver disease (OR 1.7) and female sex (OR 1.9) had strong association with metabolic syndrome. 22.4% of normal-weight and overweight children aged 5-10 years had fatty liver. A high proportion (18.9%) of normal-weight children with fatty liver on ultrasound indicates the silent burden in the population.

Selective androgen receptor modulators: in vitro and in vivo metabolism and analysis

NARCIS (Netherlands)

Rijke, de E.; Essers, M.L.; Rijk, J.C.W.; Thevis, M.; Bovee, T.F.H.; Ginkel, van L.A.; Sterk, S.S.

2013-01-01

For future targeted screening in National Residue Control Programmes, the metabolism of seven SARMs, from the arylpropionamide and the quinolinone classes, was studied in vitro using S9 bovine liver enzymes. Metabolites were detected and identified with ultra-performance liquid chromatography (UPLC)

[Comparative metabolism of three amide alkaloids from Piper longum in five different species of liver microsomes].

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He, Huan; Guo, Wei-Wei; Chen, Xiao-Qing; Zhao, Hai-Yu; Wu, Xia

2016-08-01

Piperine, piperlonguminine and pellitorine are three major amide alkaloids from Piper longum, showing a variety of pharmacological activities. In order to investigate the different metabolism pathways of these compounds in five species of liver microsomes in vitro, the data of full mass spectrum, and MS2, MS3 spectra of these three alkaloids were collected and analyzed by using ultra-high-performance liquid chromatography coupled with a LTQ-orbitrap mass spectrometer (UHPLC-LTQ-Orbitrap MS); gragment ion information was collected and combined with fragmentation regularities of mass spectra and accurate mass spectrometry data of metabolites, to compare the metabolism difference of three amide alkaloids in liver microsomes of human, rhesus monkey, Beagle dogs, rats and mice. 3 metabolites of piperine, 2 metabolites of piperlonguminine and 1 metabolite of pellitorine were identified quickly. The results showed that the major metabolic pathways of these amide alkaloids in liver microsomes were methylenedioxy group demethylation and oxidation reaction, and metabolic rates were different between species. This study provides basis for further research on in vivo metabolism of piperine analogues from Piper longum. Copyright© by the Chinese Pharmaceutical Association.

Determination of aluminium induced metabolic changes in mice liver: a Fourier transform infrared spectroscopy study.

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Sivakumar, S; Sivasubramanian, J; Khatiwada, Chandra Prasad; Manivannan, J; Raja, B

2013-06-01

In this study, we made a new approach to evaluate aluminium induced metabolic changes in liver tissue of mice using Fourier transform infrared spectroscopy analysis taking one step further in correlation with strong biochemical evidence. This finding reveals the alterations on the major biochemical constituents, such as lipids, proteins, nucleic acids and glycogen of the liver tissues of mice. The peak area value of amide A significantly decrease from 288.278±3.121 to 189.872±2.012 between control and aluminium treated liver tissue respectively. Amide I and amide II peak area value also decrease from 40.749±2.052 to 21.170±1.311 and 13.167±1.441 to 8.953±0.548 in aluminium treated liver tissue respectively. This result suggests an alteration in the protein profile. The absence of olefinicCH stretching band and CO stretching of triglycerides in aluminium treated liver suggests an altered lipid levels due to aluminium exposure. Significant shift in the peak position of glycogen may be the interruption of aluminium in the calcium metabolism and the reduced level of calcium. The overall findings exhibit that the liver metabolic program is altered through increasing the structural modification in proteins, triglycerides and quantitative alteration in proteins, lipids, and glycogen. All the above mentioned modifications were protected in desferrioxamine treated mice. Histopathological results also revealed impairment of aluminium induced alterations in liver tissue. The results of the FTIR study were found to be in agreement with biochemical studies and which demonstrate FTIR can be used successfully to indicate the molecular level changes. Copyright © 2013 Elsevier B.V. All rights reserved.

Effect of specific amino acids on hepatic lipid metabolism in fructose-induced non-alcoholic fatty liver disease.

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Jegatheesan, Prasanthi; Beutheu, Stéphanie; Ventura, Gabrielle; Sarfati, Gilles; Nubret, Esther; Kapel, Nathalie; Waligora-Dupriet, Anne-Judith; Bergheim, Ina; Cynober, Luc; De-Bandt, Jean-Pascal

2016-02-01

Fructose diets have been shown to induce insulin resistance and to alter liver metabolism and gut barrier function, ultimately leading to non-alcoholic fatty liver disease. Citrulline, Glutamine and Arginine may improve insulin sensitivity and have beneficial effects on gut trophicity. Our aim was to evaluate their effects on liver and gut functions in a rat model of fructose-induced non-alcoholic fatty liver disease. Male Sprague-Dawley rats (n = 58) received a 4-week fructose (60%) diet or standard chow with or without Citrulline (0.15 g/d) or an isomolar amount of Arginine or Glutamine. All diets were made isonitrogenous by addition of non-essential amino acids. At week 4, nutritional and metabolic status (plasma glucose, insulin, cholesterol, triglycerides and amino acids, net intestinal absorption) was determined; steatosis (hepatic triglycerides content, histological examination) and hepatic function (plasma aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, bilirubin) were assessed; and gut barrier integrity (myeloperoxidase activity, portal endotoxemia, tight junction protein expression and localization) and intestinal and hepatic inflammation were evaluated. We also assessed diets effects on caecal microbiota. In these experimental isonitrogenous fructose diet conditions, fructose led to steatosis with dyslipidemia but without altering glucose homeostasis, liver function or gut permeability. Fructose significantly decreased Bifidobacterium and Lactobacillus and tended to increase endotoxemia. Arginine and Glutamine supplements were ineffective but Citrulline supplementation prevented hypertriglyceridemia and attenuated liver fat accumulation. While nitrogen supply alone can attenuate fructose-induced non-alcoholic fatty liver disease, Citrulline appears to act directly on hepatic lipid metabolism by partially preventing hypertriglyceridemia and steatosis. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition

The Effects of Liver Transplantation on the Bone Metabolism and Gonadal Functions

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Funda Atamaz

2005-06-01

Full Text Available The present study was designed to evaluate the effects of liver transplantation (LT on the bone mineral density (BMD, characteristics of bone turnover, mineral metabolism and sex hormons. Fifty one patients (34 men, 11 women aged 43.5 ± 12.1, who underwent LT were studied, assessing the following parameters: lumbar spine and proximal femur BMD, osteocalcin, deoxypyridinoline (DPD, parathyroid hormone (PTH, free testesterone (FT, gonadotropins (FSH, LH, tyroid hormones, growth hormone (GH and blood/ 24-hours urine Ca and P. All the measures were obtained at baseline and at 3rd month after LT. At baseline, 12 patients (%23.5 had osteoporosis, 22 patients (%43.1 had osteopenia and the mean BMD was 0.892 ± 0.1 for lumbar spine. Whereas, osteoporosis was seen less at femoral neck and total femur: 5 (%9.8 and 4 (%7.8, respectively. Three months after LT, 3.9% drop for lumbar spine, 5.3% drop for femur neck, 6.3% drop for total femur were observed, in BMD these decreases were statistically significant for all sites (p<0.05. The thyroid hormones, GH, PTH, blood Ca, P and osteocalcin levels and urinary DPD excretion were within normal range, while the levels of FSH and LH in women and level of FT in men were lower than normal range. After LT, statistically significant increases were observed in the PTH, osteocalcin, DPD, FSH, LH and FT levels (p<0.05. There was a highly significant negative correlation between duration of liver disease and all the BMD measures (p<0.01. Consequently, the increased osteoporosis ratio which was characterized by high bone turnover was found in patients who underwent LT in this study. The normalization of liver functions following LT was characterized by an early rise in sex hormones.

Nonalcoholic Fatty Liver Disease/Non-Alcoholic Steatohepatitis in Childhood: Endocrine-Metabolic “Mal-Programming”

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Manti, Sara; Romano, Claudio; Chirico, Valeria; Filippelli, Martina; Cuppari, Caterina; Loddo, Italia; Salpietro, Carmelo; Arrigo, Teresa

2014-01-01

Context: Nonalcoholic Fatty Liver Disease (NAFLD) is the major chronic liver disease in the pediatric population. NAFLD includes a broad spectrum of abnormalities (inflammation, fibrosis and cirrhosis), ranging from accumulation of fat (also known as steatosis) towards non-alcoholic steatohepatitis (NASH). The development of NAFLD in children is significantly increased. Evidence Acquisition: A literature search of electronic databases was undertaken for the major studies published from 1998 to today. The databases searched were: PubMed, EMBASE, Orphanet, Midline and Cochrane Library. We used the key words: "non-alcoholic fatty liver disease, children, non-alcoholic steatohepatitis and fatty liver". Results: NAFLD/NASH is probably promoted by “multiple parallel hits”: environmental and genetic factors, systemic immunological disorders (oxidative stress, persistent-low grade of inflammation) as well as obesity and metabolic alterations (insulin resistance and metabolic syndrome). However its exact cause still underdiagnosed and unknown. Conclusions: Pediatric NAFLD/NASH is emerging problem. Longitudinal follow-up studies, unfortunately still insufficient, are needed to better understand the natural history and outcome of NAFLD in children. This review focuses on the current knowledge regarding the epidemiology, pathogenesis, environmental, genetic and metabolic factors of disease. The review also highlights the importance of studying the underlying mechanisms of pediatric NAFLD and the need for complete and personalized approach in the management of NAFLD/NASH. PMID:24829591

Molecular modifications of cholesterol metabolism in the liver and the brain after chronic contamination with cesium 137.

Science.gov (United States)

Racine, R; Grandcolas, L; Grison, S; Gourmelon, P; Guéguen, Y; Veyssière, G; Souidi, M

2009-07-01

Twenty years after Chernobyl accident, the daily ingestion of foodstuff grown on contaminated grounds remains the main source for internal exposure to ionizing radiations, and primarily to cesium 137 ((137)Cs). Though the effects of a long-term internal contamination with radionuclides are poorly documented, several non-cancerous pathologies have been described in this population. However, lipid metabolism was never investigated after chronic internal contamination although disturbances were observed in externally-exposed people. In this regard, we assessed the effects of a chronic ingestion of (137)Cs on hepatic and cerebral cholesterol metabolism. To mimic a chronically-exposed population, rats were given (137)Cs-supplemented water at a post-accidental dose (150 Bq/rat/day) during 9 months. The plasma profile, and brain and liver cholesterol concentrations were unchanged. A decrease of ACAT 2, Apo E, and LXRmRNA levels was recorded in the liver. In the brain, a decrease of CYP27A1 and ACAT 1 gene expression was observed. These results clearly show that cholesterol metabolism is not disrupted by a chronic ingestion of (137)Cs, although several molecular alterations are observed. This work would be interestingly completed by studying the influence of (137)Cs in models likely more sensitive to contaminants, such as the fetus or individuals susceptible to a lipidic disease.

Potential use of metabolic breath tests to assess liver disease and prognosis: has the time arrived for routine use in the clinic?

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Stravitz, R Todd; Ilan, Yaron

2017-03-01

The progression of liver disease may be unique among organ system diseases in that progressive fibrosis compromises not only the sufficiency of hepatocyte mass but also impairs blood flow to the liver, resulting in porto-systemic shunting. Although liver biopsy as an assessment of fibrosis has become the key biomarker of and target for new therapies, it is invasive and subject to sampling error, and cannot quantify metabolic function or porto-systemic shunting. Measurement of the hepatic venous pressure gradient accommodates some of the deficiencies of biopsy but requires expertise not widely available and misses minor changes in hepatocellular mass and thereby information about metabolic function. Thus, an unmet need in clinical hepatology remains unfulfilled: a noninvasive biomarker which quantitates both the hepatocellular insufficiency and porto-systemic shunting inherent in progressive hepatic fibrosis. Ideally, such a biomarker should correlate with clinical endpoints including liver-related survival and cirrhotic complications, be performed at the point-of-care, and be affordable and easy to use. This review, an expert opinion, summarizes background and recent data suggesting that metabolic breath tests may now meet these requirements and have a valid place in clinical hepatology to supplant the time-honoured assessment of hepatic fibrosis. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Stereoselective in vitro metabolism of rhynchophylline and isorhynchophylline epimers of Uncaria rhynchophylla in rat liver microsomes.

Science.gov (United States)

Wang, Xin; Qiao, Zhou; Liu, Jia; Zheng, Mei; Liu, Wenyuan; Wu, Chunyong

2017-11-10

1. The objective was to investigate the underlying mechanism of the stereoselectivity in the metabolism of rhynchophylline (RIN) and isorhynchophylline (IRN) epimers in rat liver microsomes (RLM). 2. After incubation, eight metabolites of RIN (M1-5) and IRN (M6-8) reacted at A- and C-ring were identified using LC-Q-TOF/MS. Metabolic pathways included oxidation, hydroxylation, N-oxidation and dehydrogenation. In addition, hydroxylation at A-ring was the major metabolic pathway for RIN whereas the oxidation at C-ring was the major one for IRN. 3. Enzyme kinetics showed that the intrinsic clearance (CL int ) for IRN elimination was 1.9-fold higher than RIN and the degradation half-life (T 1/2 ) of RIN was 4.7-fold higher than that of IRN, indicating IRN was more favorable to be metabolized than RIN in RLM. 4. Data from chemical inhibition study demonstrated CYP3A was the predominant isoform involved in the metabolic elimination of both epimers, as well as the formation of M1-8. 5. In conclusion, data revealed that due to the spatial configurations at C-7 position, RIN and IRN epimers possessed different hepatic metabolic pathways and elimination rates which were mainly mediated by CYP3A.

Competing pathways in drug metabolism. I. Effect of input concentration on the conjugation of gentisamide in the once-through in situ perfused rat liver preparation

International Nuclear Information System (INIS)

Morris, M.E.; Yuen, V.; Tang, B.K.; Pang, K.S.

1988-01-01

Sulfation and glucuronidation are two parallel pathways for the metabolism of phenolic substrates. Gentisamide (GAM) was used as a model compound to examine the effects of parallel competing pathways on drug disappearance and metabolite formation in the once-through perfused rat liver preparation. GAM was found to form one glucuronide (GAM-5G) and two sulfate (GAM-2S and GAM-5S) conjugates. These GAM conjugates were biosynthesized in recirculating rat liver preparations, and were isolated by preparative high-performance liquid chromatography. Specific incorporation of 35S-sodium sulfate and [14C]glucose into GAM sulfate and glucuronide conjugates revealed corresponding elution patterns as labeled GAM metabolites. Their identities were characterized by enzymatic and acid hydrolyses and by NMR spectroscopy. Gentisamide-5-sulfate (GAM-5S) and gentisamide-5-glucuronide (GAM-5G) are major metabolites, and gentisamide-2-sulfate (GAM-2S) is a minor metabolite. Single-pass rat liver perfusions were used to examine the effect of stepwise increases/decreases of input GAM concentration (CIn) on the extraction ratio (E) of GAM and formation of metabolites. The E of GAM remained constant (about 0.89) at input concentrations from 0.9 to 120 microM and decreased at CIn greater than 120 microM. Metabolite patterns, however, changed with GAM CIn, even when E was constant at CIn up to 120 microM. GAM-5S was present as the major metabolite of GAM at all GAM CInS in most liver preparations but the proportions of GAM-5S and GAM-2S decreased at increasing CIn; the proportion of GAM-5G, a minor metabolite at low CIn, increased with increasing CIn. Biliary excretion rates at steady state accounted for 5.3 +/- 2.7% (mean +/- S.D.) of the input rate: GAM-5G was the predominant metabolite found

Application of chimeric mice with humanized liver for study of human-specific drug metabolism.

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Bateman, Thomas J; Reddy, Vijay G B; Kakuni, Masakazu; Morikawa, Yoshio; Kumar, Sanjeev

2014-06-01

Human-specific or disproportionately abundant human metabolites of drug candidates that are not adequately formed and qualified in preclinical safety assessment species pose an important drug development challenge. Furthermore, the overall metabolic profile of drug candidates in humans is an important determinant of their drug-drug interaction susceptibility. These risks can be effectively assessed and/or mitigated if human metabolic profile of the drug candidate could reliably be determined in early development. However, currently available in vitro human models (e.g., liver microsomes, hepatocytes) are often inadequate in this regard. Furthermore, the conduct of definitive radiolabeled human ADME studies is an expensive and time-consuming endeavor that is more suited for later in development when the risk of failure has been reduced. We evaluated a recently developed chimeric mouse model with humanized liver on uPA/SCID background for its ability to predict human disposition of four model drugs (lamotrigine, diclofenac, MRK-A, and propafenone) that are known to exhibit human-specific metabolism. The results from these studies demonstrate that chimeric mice were able to reproduce the human-specific metabolite profile for lamotrigine, diclofenac, and MRK-A. In the case of propafenone, however, the human-specific metabolism was not detected as a predominant pathway, and the metabolite profiles in native and humanized mice were similar; this was attributed to the presence of residual highly active propafenone-metabolizing mouse enzymes in chimeric mice. Overall, the data indicate that the chimeric mice with humanized liver have the potential to be a useful tool for the prediction of human-specific metabolism of xenobiotics and warrant further investigation.

[In vitro metabolism of fenbendazole prodrug].

Science.gov (United States)

Wen, Ai-Dan; Duan, Li-Ping; Liu, Cong-Shan; Tao, Yi; Xue, Jian; Wu, Ning-Bo; Jiang, Bin; Zhang, Hao-Bing

2013-02-01

Synthesized fenbendazole prodrug N-methoxycarbonyl-N'-(2-nitro-4-phenylthiophenyl) thiourea (MPT) was analyzed in vitro in artificial gastric juice, intestinal juice and mouse liver homogenate model by using HPLC method, and metabolic curve was then generated. MPT was tested against Echinococcus granulosus protoscolices in vitro. The result showed that MPT could be metabolized in the three biological media, and to the active compound fenbendazole in liver homogenate, with a metabolic rate of 7.92%. Besides, the prodrug showed a weak activity against E. granulosus protoscolices with a mortality of 45.9%.

Comparison of hepatotoxicity and metabolism of butyltin compounds in the liver of mice, rats and guinea pigs

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Ueno, Shunji; Kashimoto, Takashige; Susa, Nobuyuki; Ishii, Masamitsu; Chiba, Toshikazu [Laboratory of Veterinary Public Health, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, 034-8628, Towada-shi, Aomori (Japan); Mutoh, Ken-ichiro [Laboratory of Veterinary Anatomy, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, 034-8628, Towada-shi, Aomori (Japan); School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, 034-8628, Towada-shi, Aomori (Japan); Hoshi, Fumio [Laboratory of Veterinary Anatomy, School of Veterinary Medicine and Animal Sciences, Kitasato University, Higashi 23-35-1, 034-8628, Towada-shi, Aomori (Japan); Suzuki, Takashi [Laboratory of Environmental Health and Toxicology, Kyoto Prefectural University, Hangi-cho, Shimogamo, Sakyo-ku, 606-5822, Kyoto (Japan); Sugiyama, Masayasu [Sugiyama Pharmacy, 1335-1 Shimotama, Tamagawa-cho, 759-3112, Yamaguchi (Japan)

2003-03-01

The hepatotoxicity of tributyltin chloride (TBTC) and dibutyltin dichloride (DBTC) was compared among mice, rats and guinea pigs in vivo. Further, the metabolism of these butyltin compounds in the liver was also investigated in these species. The oral administration of TBTC and DBTC to mice induced obvious liver injury, as demonstrated by both serodiagnosis and histopathological diagnosis. The concentrations of TBTC and DBTC that induced hepatotoxicity in mice at 24 h after oral administration were 180 and 60 {mu}mol/kg, respectively. In the case of rats, the liver injury induced by TBTC and DBTC was detected at 24 h by the serodiagnosis, but not by histopathological diagnosis. On the other hand, in guinea pigs, TBTC and DBTC administration did not produce any clear liver injury at 24 h, as evaluated by these two diagnostic methods. Thus, the following ranking was obtained with regard to increasing order of sensitivity to liver injury caused by TBTC and DBTC: mice, rats and guinea pigs. The total butyltin contents in the liver of mice were equivalent at 3 h and 24 h after the administration of TBTC or DBTC; however, the contents in the liver of rats and guinea pigs were relatively lower at 3 h and higher at 24 h than those of mice, although there were no differences between rats and guinea pigs in the total liver butyltin content. Concerning the liver metabolism of these butyltin compounds, the main form of butyltin compounds in these animals treated with TBTC was DBTC within 3 h after oral administration, while the main metabolites at 24 h were different in each species, indicating that the liver metabolism of TBTC might vary by animal type. When the animals were treated with DBTC orally, DBTC was hardly metabolized in the livers of these animals even at 24 h, and the liver levels of DBTC were two times greater in mice and guinea pigs than in rats at 3 h and were lower in mice at 24 h than in rats and guinea pigs. The analysis of cellular distributions of DBTC in

Effects of Castration on Expression of Lipid Metabolism Genes in the Liver of Korean Cattle

OpenAIRE

Baik, Myunggi; Nguyen, Trang Hoa; Jeong, Jin Young; Piao, Min Yu; Kang, Hyeok Joong

2015-01-01

Castration induces the accumulation of body fat and deposition of intramuscular fat in Korean cattle, resulting in improved beef quality. However, little is known about the metabolic adaptations in the liver following castration. To understand changes in lipid metabolism following castration, hepatic expression levels of lipid metabolism genes were compared between Korean bulls and steers. Steers had higher (p

Metabolic Circuit Involving Free Fatty Acids, microRNA 122, and Triglyceride Synthesis in Liver and Muscle Tissues.

Science.gov (United States)

Chai, Chofit; Rivkin, Mila; Berkovits, Liav; Simerzin, Alina; Zorde-Khvalevsky, Elina; Rosenberg, Nofar; Klein, Shiri; Yaish, Dayana; Durst, Ronen; Shpitzen, Shoshana; Udi, Shiran; Tam, Joseph; Heeren, Joerg; Worthmann, Anna; Schramm, Christoph; Kluwe, Johannes; Ravid, Revital; Hornstein, Eran; Giladi, Hilla; Galun, Eithan

2017-11-01

Effective treatments are needed for hepatic steatosis characterized by accumulation of triglycerides in hepatocytes, which leads to hepatocellular carcinoma. MicroRNA 122 (MIR122) is expressed only in the liver, where it regulates lipid metabolism. We investigated the mechanism by which free fatty acids (FFAs) regulate MIR122 expression and the effect of MIR122 on triglyceride synthesis. We analyzed MIR122 promoter activity and validated its target mRNAs by transfection of Luciferase reporter plasmids into Huh7, BNL-1ME, and HEK293 cultured cell lines. We measured levels of microRNAs and mRNAs by quantitative real-time PCR analysis of RNA extracted from plasma, liver, muscle, and adipose tissues of C57BL/6 mice given the FFA-inducer CL316243. MIR122 was inhibited using an inhibitor of MIR122. Metabolic profiles of mice were determined using metabolic chambers and by histologic analyses of liver tissues. We performed RNA sequence analyses to identify metabolic pathways involving MIR122. We validated human Agpat1 and Dgat1 mRNAs, involved in triglyceride synthesis, as targets of MIR122. FFAs increased MIR122 expression in livers of mice by activating the retinoic acid-related orphan receptor alpha, and induced secretion of MIR122 from liver to blood. Circulating MIR122 entered muscle and adipose tissues of mice, reducing mRNA levels of genes involved in triglyceride synthesis. Mice injected with an inhibitor of MIR122 and then given CL316243, accumulated triglycerides in liver and muscle tissues, and had reduced rates of β-oxidation. There was a positive correlation between level of FFAs and level of MIR122 in plasma samples from 6 healthy individuals, collected before and during fasting. In biochemical and histologic studies of plasma, liver, muscle, and adipose tissues from mice, we found that FFAs increase hepatic expression and secretion of MIR122, which regulates energy storage vs expenditure in liver and peripheral tissues. Strategies to reduce

Potential role of liver enzymes levels as predictor markers of glucose metabolism disorders in Tunisian population.

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Bouhajja, Houda; Abdelhedi, Rania; Amouri, Ali; Hadj Kacem, Faten; Marrakchi, Rim; Safi, Wajdi; Mrabet, Houcem; Chtourou, Lassaad; Charfi, Nadia; Fourati, Mouna; Bensassi, Salwa; Jamoussi, Kamel; Abid, Mohamed; Ayadi, Hammadi; Feki, Mouna Mnif; Elleuch, Noura Bougacha

2018-03-10

The relationship between liver enzymes and type 2 diabetes (T2D) risk is inconclusive. We aimed to evaluate the association between liver markers and risk of carbohydrate metabolism disorders and their discriminatory power for T2D prediction. This cross-sectional study enrolled 216 participants classified as normoglycemic, prediabetes, newly-diagnosed diabetes and diagnosed diabetes. All participants underwent anthropometric and biochemical measurements. The relationship between hepatic enzymes and glucose metabolism markers was evaluated by ANCOVA analyses. The associations between liver enzymes and incident carbohydrate metabolism disorders were analyzed through logistic regression and their discriminatory capacity for T2D by receiver operating characteristic (ROC) analysis. High alkaline phosphatase (AP), alanine aminotransferase (ALT), γ-glutamyltransferase (γGT) and aspartate aminotrasferase (AST) levels were independently related to decreased insulin sensitivity. Interestingly, higher AP level was significantly associated with increased risk of prediabetes (p=0.017), newly-diagnosed diabetes (p=0.004) and T2D (p=0.007). Elevated γGT level was an independent risk factor for T2D (p=0.032) and undiagnosed-T2D (p=0.010) in prediabetic and normoglycemic subjects, respectively. In ROC analysis, AP was a powerful predictor of incident diabetes and significantly improved T2D prediction. Liver enzymes within normal range, specifically AP levels, are associated with increased risk of carbohydrate metabolism disorders and significantly improved T2D prediction.

High expression of liver histone deacetylase 3 contributes to high-fat-diet-induced metabolic syndrome by suppressing the PPAR-γ and LXR-α-pathways in E3 rats.

Science.gov (United States)

Li, Dongmin; Wang, Xuan; Ren, Wuchao; Ren, Juan; Lan, Xi; Wang, Feimiao; Li, Hongmin; Zhang, Fujun; Han, Yan; Song, Tianbao; Holmdahl, Rikard; Lu, Shemin

2011-09-15

In the previous experiment, we found that there was a different response between E3 rats and DA.1U rats to high-fat-diet-induced metabolic syndrome (HFD-MetS). The aim of this study was to explore the cause and molecular mechanism of the genetic difference in susceptibility to metabolic syndrome in E3 rats as compared with DA.1U rats. Firstly, a 12-week HFD-MetS model in E3 and DA.1U rats was carried out and assessed. Then, the expression of key insulin signaling molecules, metabolic nuclear receptors, metabolic key enzymes and histone deacetylases (Hdacs) was determined by different methods. Finally, the effects of overexpression and disruption of Hdac3 on metabolic nuclear receptors were analyzed in CBRH-7919 cells and primarily-hepatic cells from DA.1U and E3 rats. We found that E3 rats were susceptible, while DA.1U rats were resisted to HFD-MetS. The expression of liver X receptor α,β (LXR-α,β), farnesoid X receptor (FXR), peroxisome proliferator activated receptor γ (PPAR-γ) and cholesterol 7α-hydroxylase (CYP7A1) increased markedly in DA.1U rat liver, whereas they decreased significantly in E3 rats. The expression of Hdac3 increased by HFD treatment in both E3 and DA.1U rat livers, but the constitutive Hdac3 expression was lower in DA.IU rat liver than in E3 rat liver. Importantly, overexpression of Hdac3 could downregulate the expression of LXR-α, PPAR-γ and CYP7A1 in both CBRH-7919 cells and primarily cultured hepatic cells from DA.IU rats. On the contrary, disruption of Hdac3 by shRNA upregulated the expression of LXR-α, PPAR-γ and CYP7A1 in both CBRH-7919 cells and primarily cultured hepatic cells from E3 rats. The results suggested that a high constitutive expression of Hdac3 inhibiting the expression of PPAR-γ, LXR-α and CYP7A1 in liver contributes to HFD-MetS in E3 rats. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Central melanin-concentrating hormone influences liver and adipose metabolism via specific hypothalamic nuclei and efferent autonomic/JNK1 pathways.

Science.gov (United States)

Imbernon, Monica; Beiroa, Daniel; Vázquez, María J; Morgan, Donald A; Veyrat-Durebex, Christelle; Porteiro, Begoña; Díaz-Arteaga, Adenis; Senra, Ana; Busquets, Silvia; Velásquez, Douglas A; Al-Massadi, Omar; Varela, Luis; Gándara, Marina; López-Soriano, Francisco-Javier; Gallego, Rosalía; Seoane, Luisa M; Argiles, Josep M; López, Miguel; Davis, Roger J; Sabio, Guadalupe; Rohner-Jeanrenaud, Françoise; Rahmouni, Kamal; Dieguez, Carlos; Nogueiras, Ruben

2013-03-01

Specific neuronal circuits modulate autonomic outflow to liver and white adipose tissue. Melanin-concentrating hormone (MCH)-deficient mice are hypophagic, lean, and do not develop hepatosteatosis when fed a high-fat diet. Herein, we sought to investigate the role of MCH, an orexigenic neuropeptide specifically expressed in the lateral hypothalamic area, on hepatic and adipocyte metabolism. Chronic central administration of MCH and adenoviral vectors increasing MCH signaling were performed in rats and mice. Vagal denervation was performed to assess its effect on liver metabolism. The peripheral effects on lipid metabolism were assessed by real-time polymerase chain reaction and Western blot. We showed that the activation of MCH receptors promotes nonalcoholic fatty liver disease through the parasympathetic nervous system, whereas it increases fat deposition in white adipose tissue via the suppression of sympathetic traffic. These metabolic actions are independent of parallel changes in food intake and energy expenditure. In the liver, MCH triggers lipid accumulation and lipid uptake, with c-Jun N-terminal kinase being an essential player, whereas in adipocytes MCH induces metabolic pathways that promote lipid storage and decreases lipid mobilization. Genetic activation of MCH receptors or infusion of MCH specifically in the lateral hypothalamic area modulated hepatic lipid metabolism, whereas the specific activation of this receptor in the arcuate nucleus affected adipocyte metabolism. Our findings show that central MCH directly controls hepatic and adipocyte metabolism through different pathways. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

An update on the use of benzoate, phenylacetate and phenylbutyrate ammonia scavengers for interrogating and modifying liver nitrogen metabolism and its implications in urea cycle disorders and liver disease.

Science.gov (United States)

De Las Heras, Javier; Aldámiz-Echevarría, Luis; Martínez-Chantar, María-Luz; Delgado, Teresa C

2017-04-01

Ammonia-scavenging drugs, benzoate and phenylacetate (PA)/phenylbutyrate (PB), modulate hepatic nitrogen metabolism mainly by providing alternative pathways for nitrogen disposal. Areas covered: We review the major findings and potential novel applications of ammonia-scavenging drugs, focusing on urea cycle disorders and liver disease. Expert opinion: For over 40 years, ammonia-scavenging drugs have been used in the treatment of urea cycle disorders. Recently, the use of these compounds has been advocated in acute liver failure and cirrhosis for reducing hyperammonemic-induced hepatic encephalopathy. The efficacy and mechanisms underlying the antitumor effects of these ammonia-scavenging drugs in liver cancer are more controversial and are discussed in the review. Overall, as ammonia-scavenging drugs are usually safe and well tolerated among cancer patients, further studies should be instigated to explore the role of these drugs in liver cancer. Considering the relevance of glutamine metabolism to the progression and resolution of liver disease, we propose that ammonia-scavenging drugs might also be used to non-invasively probe liver glutamine metabolism in vivo. Finally, novel derivatives of classical ammonia-scavenging drugs with fewer and less severe adverse effects are currently being developed and used in clinical trials for the treatment of acute liver failure and cirrhosis.

Methylation of Septin9 mediated by DNMT3a enhances hepatic stellate cells activation and liver fibrogenesis

Energy Technology Data Exchange (ETDEWEB)

Wu, Yuting, E-mail: wuyuting1302@sina.com; Bu, Fangtian; Yu, Haixia; Li, Wanxia; Huang, Cheng; Meng, Xiaoming; Zhang, Lei; Ma, Taotao; Li, Jun, E-mail: lj@ahmu.edu.cn

2017-01-15

Liver fibrosis, resulting from chronic and persistent injury to the liver, is a worldwide health problem. Advanced liver fibrosis results in cirrhosis, liver failure and even hepatocellular cancer (HCC), often eventually requiring liver transplantation, poses a huge health burden on the global community. However, the specific pathogenesis of liver fibrosis remains not fully understood. Numerous basic and clinical studies have provided evidence that epigenetic modifications, especially DNA methylation, might contribute to the activation of hepatic stellate cells (HSCs), the pivotal cell type responsible for the fibrous scar in liver. Here, reduced representation bisulfite sequencing (RRBS) and bisulfite pyrosequencing PCR (BSP) analysis identified hypermethylation status of Septin9 (Sept9) gene in liver fibrogenesis. Sept9 protein was dramatically decreased in livers of CCl4-treated mice and immortalized HSC-T6 cells exposed to TGF-β1. Nevertheless, the suppression of Sept9 could be blocked by DNMT3a-siRNA and DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5-azadC). Overexpressed Sept9 attenuated TGF-β1-induced expression of myofibroblast markers α-SMA and Col1a1, accompanied by up-regulation of cell apoptosis-related proteins. Conversely, RNAi-mediated silencing of Sept9 enhanced accumulation of extracellular matrix. These observations suggested that Sept9 contributed to alleviate liver fibrosis might partially through promoting activated HSCs apoptosis and this anti-fibrogenesis effect might be blocked by DNMT-3a mediated methylation of Sept9. Therefore, pharmacological agents that inhibit Sept9 methylation and increase its expression could be considered as valuable treatments for liver fibrosis. - Highlights: • This is the first report of Sept9 methylation and function in liver fibrosis. • Ectopic expression of Sept9 could block the liver fibrogenesis. • DNMT3a might be responsible for the suppression of Sept9 in liver fibrosis.

Methylation of Septin9 mediated by DNMT3a enhances hepatic stellate cells activation and liver fibrogenesis

International Nuclear Information System (INIS)

Wu, Yuting; Bu, Fangtian; Yu, Haixia; Li, Wanxia; Huang, Cheng; Meng, Xiaoming; Zhang, Lei; Ma, Taotao; Li, Jun

2017-01-01

Liver fibrosis, resulting from chronic and persistent injury to the liver, is a worldwide health problem. Advanced liver fibrosis results in cirrhosis, liver failure and even hepatocellular cancer (HCC), often eventually requiring liver transplantation, poses a huge health burden on the global community. However, the specific pathogenesis of liver fibrosis remains not fully understood. Numerous basic and clinical studies have provided evidence that epigenetic modifications, especially DNA methylation, might contribute to the activation of hepatic stellate cells (HSCs), the pivotal cell type responsible for the fibrous scar in liver. Here, reduced representation bisulfite sequencing (RRBS) and bisulfite pyrosequencing PCR (BSP) analysis identified hypermethylation status of Septin9 (Sept9) gene in liver fibrogenesis. Sept9 protein was dramatically decreased in livers of CCl4-treated mice and immortalized HSC-T6 cells exposed to TGF-β1. Nevertheless, the suppression of Sept9 could be blocked by DNMT3a-siRNA and DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5-azadC). Overexpressed Sept9 attenuated TGF-β1-induced expression of myofibroblast markers α-SMA and Col1a1, accompanied by up-regulation of cell apoptosis-related proteins. Conversely, RNAi-mediated silencing of Sept9 enhanced accumulation of extracellular matrix. These observations suggested that Sept9 contributed to alleviate liver fibrosis might partially through promoting activated HSCs apoptosis and this anti-fibrogenesis effect might be blocked by DNMT-3a mediated methylation of Sept9. Therefore, pharmacological agents that inhibit Sept9 methylation and increase its expression could be considered as valuable treatments for liver fibrosis. - Highlights: • This is the first report of Sept9 methylation and function in liver fibrosis. • Ectopic expression of Sept9 could block the liver fibrogenesis. • DNMT3a might be responsible for the suppression of Sept9 in liver fibrosis.

Metabolism of 5-fluorouracil in human liver: an in vivo 19F NMR study

International Nuclear Information System (INIS)

Mohankrishnan, P.; Sprigg, J.; Cardwell, D.; Komoroski, R.A.; Hutchins, L.; Nauke, S.; Williamson, M.R.; Jagannathan, N.R.

1999-01-01

In vivo fluorine-19 nuclear magnetic resonance ( 19 F NMR) spectroscopy was used to study the metabolism and pharmacokinetics of 5-fluorouracil (5-FU) in human liver. Nine patients received 5-FU, and additional chemotherapeutic agents (methotrexate, leucovorin, or levamisole) either prophylactically after breast cancer surgery or for colorectal cancer. The time constant for the disappearance of 5-FU from the liver in vivo varied from 5 to 17 min, while the time constant for the appearance of α-fluoro-β-alanine (the major catabolite of 5 FU) varied from 7 to 86 min. The modulators of 5-FU metabolism did not appear to affect the time constant for the disappearance of 5-FU from the liver or for the appearance of α-fluoro-β-alanine. Results obtained indicate that the pharmacokinetics of 5-FU and α-fluoro-β-alanine may vary substantially at different times in a given individual. (author)

Fumarylacetoacetate hydrolase deficient pigs are a novel large animal model of metabolic liver disease

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Raymond D. Hickey

2014-07-01

FAH-deficiency produced a lethal defect in utero that was corrected by administration of 2-(2-nitro-4-trifluoromethylbenzoyl-1,3 cyclohexanedione (NTBC throughout pregnancy. Animals on NTBC were phenotypically normal at birth; however, the animals were euthanized approximately four weeks after withdrawal of NTBC due to clinical decline and physical examination findings of severe liver injury and encephalopathy consistent with acute liver failure. Biochemical and histological analyses, characterized by diffuse and severe hepatocellular damage, confirmed the diagnosis of severe liver injury. FAH−/− pigs provide the first genetically engineered large animal model of a metabolic liver disorder. Future applications of FAH−/− pigs include discovery research as a large animal model of HT1 and spontaneous acute liver failure, and preclinical testing of the efficacy of liver cell therapies, including transplantation of hepatocytes, liver stem cells, and pluripotent stem cell-derived hepatocytes.

The significance of liver in metabolism of plutonium 239

International Nuclear Information System (INIS)

Netchev, Christo.

1977-01-01

Plutonium 239 has an important toxicological significance and is widely used in the nuclear industry which makes the study of its metabolism in the organism appear of substantial interest. The role of the liver in the distribution of radionuclide and its barrier capabilities, determining to a certain extent the back transport of the isotope from the blood plasma into the gut is studied. The storage of Plutonium 239 in the organ and its reexcretion by way of the gull is quantitatively demonstrated. This question is related to the exact determination of the coefficient of absorption of the radioisotope in the digestive tract. The radionuclide is inserted into organism as PuCl 3 directly into vein jugularis and vein portae. The peculiarities of its distribution in the liver by the two ways of introduction as well as the essential differences in the radioactivity of the products of excretion by portal application are described. The mechanism of the storage of the radioisotope in the organ is explained to a great extent with its physical and chemical condition in the liver tissue. Plutonium 239 is found in the liver completely as a complex compound with the tissue proteins, the combining with globulines predominating. The dynamics of exchange of the radionuclide in the organ is determined mainly by its complex combination with the globulins. The part of nuclide connected with the other protein fractions of liver is not significant and hence they do not much influence kinetics in the organ

Trapping of cis-2-butene-1,4-dial to measure furan metabolism in human liver microsomes by cytochrome P450 enzymes.

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Gates, Leah A; Lu, Ding; Peterson, Lisa A

2012-03-01

Furan is a liver toxicant and carcinogen in rodents. It is classified as a possible human carcinogen, but the human health effects of furan exposure remain unknown. The oxidation of furan by cytochrome P450 (P450) enzymes is necessary for furan toxicity. The product of this reaction is the reactive α,β-unsaturated dialdehyde, cis-2-butene-1,4-dial (BDA). To determine whether human liver microsomes metabolize furan to BDA, a liquid chromatography/tandem mass spectrometry method was developed to detect and quantify BDA by trapping this reactive metabolite with N-acetyl-l-cysteine (NAC) and N-acetyl-l-lysine (NAL). Reaction of NAC and NAL with BDA generates N-acetyl-S-[1-(5-acetylamino-5-carboxypentyl)-1H-pyrrol-3-yl]-l-cysteine (NAC-BDA-NAL). Formation of NAC-BDA-NAL was quantified in 21 different human liver microsomal preparations. The levels of metabolism were comparable to that observed in F-344 rat and B6C3F1 mouse liver microsomes, two species known to be sensitive to furan-induced toxicity. Studies with recombinant human liver P450s indicated that CYP2E1 is the most active human liver furan oxidase. The activity of CYP2E1 as measured by p-nitrophenol hydroxylase activity was correlated to the extent of NAC-BDA-NAL formation in human liver microsomes. The formation of NAC-BDA-NAL was blocked by CYP2E1 inhibitors but not other P450 inhibitors. These results suggest that humans are capable of oxidizing furan to its toxic metabolite, BDA, at rates comparable to those of species sensitive to furan exposure. Therefore, humans may be susceptible to furan's toxic effects.

S-Adenosylmethionine and S-adenosylhomocystein metabolism in isolated rat liver. Effects of L-methionine, L-homocystein, and adenosine.

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Hoffman, D R; Marion, D W; Cornatzer, W E; Duerre, J A

1980-11-25

The effects of varying concentrations of L-methionine, L-homocysteine, and adenosine on the tissue levels of S-adenosylmethionine (AdoMet) and S-adenosyl-homocystein (AdoHcy) were investigated in perfused liver. In the normal liver, the intracellular concentration of AdoMet was dependent upon the availability of methionine. In the presence of high concentrations of methionine the maximum level of AdoMet attainable was 300 nmol/g of liver. The exogenous concentration of methionine did not alter the hepatic concentration of AdoHcy (8 to 20 nmol/g) while adenosine or homocysteine blocked hydrolysis of AdoHcy resulting in elevated levels of AdoHcy (400 to 600 nmol/g) and AdoMet (300 to 600 nmol/g). The addition of both adenosine (4mM) and homocysteine (3.4 mM) to the perfusate further increased the levels of AdoHcy (4 mumol/g) and AdoMet (1.2 mumol/g). As the concentration of AdoHcy increased, significant amounts of this compound were released into the perfusate, while AdoMet was not detected. Under all conditions where AdoHcy accumulated in the cell, a concomitant increase in the AdoMet level occurred. Apparently AdoHcy acts as a positive effector of the S-adenosylmethionine synthase. The hepatocytes did not take up significant amounts of [methyl-14C]AdoMet from the perfusate nor were any [14C]methyl groups from this compound incorporated into histones, DNA, or phospholipids. In contrast, [14C]methyl groups were readily incorporated into these macromolecules from exogenous [methyl-14C]methionine. The addition of adenosine (4 mM) and homocystein (3.4 mM) shifted the AdoMet:AdoHcy ratio from 8.2 to 0.3. Under these conditions, transmethylation was inhibited markedly.

The nucleic acid metabolism in rat liver after single and long-term administration of tritium oxide

International Nuclear Information System (INIS)

Shorokhova, V.B.

1984-01-01

It was shown that after a single administration of tritiUm oxide in a dose of 22.2 MBq/g body mass the liver mass increased, the concentration of nucleic acids decreased and the biosynthesjs rate increased dUring a one-month observation. By the end of the observation period (the first year) the parameters under study were normalized. The long-term administration of tritium oxide in daily doses of 0.37, 0.925 and 1.85 MBq/g body mass caused changes in the nucleac acid metabolism which were less manifest (at early times), than in the case of a single injection. At the same time, the long-term administration of tritium oxide in the dose of 0.925 MBq/g caused a substantial disturbance of the nucleic acid metabolism at later times (after 2-9 months)

Inhibition of mirtazapine metabolism by Ecstasy (MDMA) in isolated perfused rat liver model.

Science.gov (United States)

Jamshidfar, Sanaz; Ardakani, Yalda H; Lavasani, Hoda; Rouini, Mohammadreza

2017-06-28

Nowadays MDMA (3,4-methylendioxymethamphetamine), known as ecstasy, is widely abused among the youth because of euphoria induction in acute exposure. However, abusers are predisposed to depression in chronic consumption of this illicit compound. Mirtazapine (MRZ), an antidepressant agent, may be prescribed in MDMA-induced depression. MRZ is extensively metabolized in liver by CYP450 isoenzymes. 8-hydroxymirtazapine (8-OH) is mainly produced by CYP2D6. N-desmethylmirtazapine (NDES) is generated by CYP3A4. MDMA is also metabolized by the mentioned isoenzymes and demonstrates mechanism-based inhibition (MBI) in association with CYP2D6. Several studies revealed that MDMA showed inhibitory effects on CYP3A4. In the present study, our aim was to evaluate the impact of MDMA on the metabolism of MRZ in liver. Therefore, isolated perfused rat liver model was applied as our model of choice in this assessment. The subjects of the study were categorized into two experimental groups. Rats in the control group received MRZ-containing Krebs-Henselit buffer (1 μg/ml). Rats in the treatment group received aqueous solution of 1 mg/ml MDMA (3 mg/kg) intraperitoneally 1 hour before receiving MRZ. Perfusate samples were analyzed by HPLC. Analyses of perfusate samples showed 80% increase in the parent drug concentrations and 50% decrease in the concentrations of both metabolites in our treatment group compared to the control group. In the treatment group compared to the control group, AUC (0-120) of the parent drug demonstrated 50% increase and AUC (0-120) of 8-OH and NDES showed 70% and 60% decrease, respectively. Observed decrease in metabolic ratios were 83% and 79% for 8-OH and NDES in treatment group compared to control group, respectively. Hepatic clearance (CL h ) and intrinsic clearance (Cl int ) showed 20% and 60% decrease in treatment group compared to control group. All findings prove the inhibitory effects of ecstasy on both CYP2D6 and CYP3A4 hepatic isoenzymes. In

Effects of a 6-wk intraduodenal supplementation with quercetin on energy metabolism and indicators of liver damage in periparturient dairy cows.

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Stoldt, Ann-Kathrin; Derno, Michael; Nürnberg, Gerd; Weitzel, Joachim M; Otten, Winfried; Starke, Alexander; Wolffram, Siegfried; Metges, Cornelia C

2015-07-01

Periparturient dairy cows experience metabolic challenges that result in a negative energy balance (EB) and a range of postpartum health problems. To compensate for the negative EB, cows mobilize fatty acids from adipose tissues, which can lead to fatty liver disease, a periparturient metabolic disorder. Flavonoids, such as quercetin (Q), are polyphenolic substances found in all higher plants and have hepatoprotective potential and the ability to prevent or reduce lipid accumulation in the liver. In ruminants, few studies on the metabolic effects of Q are available, and thus this study was conducted to determine whether Q has beneficial effects on EB, lipid metabolism, and hepatoprotective effects in periparturient dairy cows. Quercetin was supplemented intraduodenally to circumvent Q degradation in the rumen. Cows (n=10) with duodenal fistulas were monitored for 7wk. Beginning 3wk before expected calving, 5 cows were treated with 100mg of quercetin dihydrate per kilogram of body weight daily in a 0.9% sodium chloride solution for a total period of 6wk, whereas the control cows received only the sodium chloride solution. The plasma flavonoid levels were higher in the Q-treated cows than in the control cows. A tendency for higher postpartum (pp) than antepartum (ap) plasma flavonoid levels was observed in the Q-treated cows than in the controls, which was potentially caused by a reduced capacity to metabolize Q. However, the metabolic status of the Q-treated cows did not differ from that of the control cows. The pp increases in plasma aspartate aminotransferase and glutamate dehydrogenase activities were less in the Q-treated cows than in the control cows. The Q had no effect on energy expenditures, but from ap to pp the cows had a slight decline in respiratory quotients. Irrespective of the treatment group, the oxidation of fat peaked after calving, suggesting that the increase occurred because of an increased supply of fatty acids from lipomobilization. In

NON-ALCOHOLIC FATTY LIVER DISEASE IN CHILDREN

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L.V. Chistova

2010-01-01

Full Text Available Metabolic syndrome that represents a totality of interrelated carbohydrate metabolism and lipid disorders, as well as a mechanism regulating arterial tension and endothelium function is one of the critical issues in pediatrics. In recent years, children with metabolic syndrome are increasingly diagnosed with liver injuries symptoms that are associated with a fatty transformation of the liver [1–3]. In this case, non-alcoholic fatty liver disease (NAFLD, a liver manifestation of metabolic syndrome is diagnosed. The diagnosis is confirmed in the absence of alcohol abuse in the past medical history, virus and autoimmune liver disease markers, elimination of toxic and drug influence, as wells as disorders of copper and iron exchange in the patient’s system. One of the key risk factors for developing NAFLD in children is overeating and reduced physical activities. It was believed in the past that NAFLD is relatively benign, however, there is evidence in current literature that this is a pathological condition that may develop and result in extreme fibrotic alterations in the liver parenchymatous tissue all the way to cirrhosis and hepatocellular carcinoma [4]. Early-stage identification and timely launch of therapy for NAFLD in children represents one of the most important objectives in modern healthcare. Key words: metabolic syndrome, non-alcoholic fatty liver disease, children, steatohepatosis. (Pediatric Pharmacology. – 2010; 7(6:68-72

Lipid biomarkers and metabolic effects of lycopene from tomato juice on liver of rats with induced hepatic steatosis.

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Bernal, Cristina; Martín-Pozuelo, Gala; Lozano, Ana B; Sevilla, Angel; García-Alonso, Javier; Canovas, Manuel; Periago, María J

2013-11-01

Nonalcoholic fatty liver disease (NAFLD) is one of the most common liver disorders, covering steatosis to nonalcoholic steatohepatitis (NASH). Dietary factors may modulate its evolution, and antioxidants have been proposed as therapeutic agents. Among them, lycopene has been demonstrated to prevent the development of steatohepatitis and even to inhibit NASH-promoted early hepatocarcinogenesis induced by a high-fat diet in rats. These conclusions have been related to its antioxidant activity; however, NAFLD is more complex than a simple redox imbalance state since it disturbs several metabolic systems in the liver. In consequence, there is a lack of information related to the action of lycopene beyond antioxidant biomarkers. In this work, NAFLD was induced in rats using a hypercholesterolemic and high-fat diet to evaluate the effect of lycopene consumption from tomato juice on liver metabolism. Several classical antioxidant biomarkers related to NAFLD were measured to check the state of this disease after 7 weeks of the controlled diet. Moreover, a metabolomics platform was applied to measure more than 70 metabolites. Results showed clear differences in the classical antioxidant biomarkers as well as in the metabolic pattern, attending not only to the diet but also to the intake of lycopene from tomato juice. Interestingly, tomato juice administration partially reverted the metabolic pattern from a high-fat diet to a normal diet even in metabolites not related to the redox state, which could lead to new targets for therapeutic agents against NAFLD and to achieving a better understanding of the role of lycopene in liver metabolism. Copyright © 2013 Elsevier Inc. All rights reserved.

Hepatic Metabolism of Sakuranetin and Its Modulating Effects on Cytochrome P450s and UDP-Glucuronosyltransferases

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Hyesoo Jeong

2018-06-01

Full Text Available Sakuranetin (SKN, found in cherry trees and rice, is a flavanone with various pharmacological activities. It is biosynthesized from naringenin in rice or cherry trees, and the metabolism of SKN has been studied in non-human species. The present study aimed to investigate the metabolic pathways of SKN in human liver microsomes and identify the phase I and phase II metabolites, as well as evaluate the potential for drug–herb interactions through the modulation of drug metabolizing enzymes (DMEs. HPLC-DAD and HPLC-electrospray mass spectrometry were used to study the metabolic stability and identify the metabolites from human liver microsomes incubated with SKN. The potential of SKN to inhibit the DMEs was evaluated by monitoring the formation of a DME-specific product. The cytochrome P450 2B6 and 3A4-inductive effects were studied using promoter reporter assays in human hepatocarcinoma cells. The major pathways for SKN metabolism include B-ring hydroxylation, 5-O-demethylation, and conjugation with glutathione or glucuronic acid. The phase I metabolites were identified as naringenin and eriodictyol. SKN was found to be a UDP-glucuronosyltransferases (UGT 1A9 inhibitor, whereas it induced transactivation of the human pregnane X receptor-mediated cytochrome P450 (CYP 3A4 gene.

[Effect of acute biliary pancreatitis on liver metabolism of phenazone].

Science.gov (United States)

Hartleb, M; Nowak, A; Nowakowska-Duława, E; Mańczyk, I; Becker, A; Kacperek, T

1990-03-01

In 22 patients with acute pancreatitis caused by biliary calculi and 9 healthy controls the rate of hepatic elimination of phenazone was measured. The aim of the study was evaluation of the oxidative-detoxicating action of the liver in this disease in relation to its severity. In pancreatitis patients the half-time (T2) of phenazone was significantly (p less than 0.01 longer than in healthy subjects (23.6 +/- 10.5 vs 13.2 +/- 7.2 hrs). The T2 of phenazone was not correlated with the concentrations of transaminases, bilirubin and prothrombin, but was correlated positively with the concentration of hepatic lactic dehydrogenase (p less than 0.001). In the initial stage of pancreatitis the T2 of phenazone was without prognostic significance and showed no agreement with Ranson's clinical-laboratory classification of the severity of the disease. The degree of impairment of the hepatic metabolism of phenazone measured with the percent difference between T2 of phenazone in both tests was significantly (p less than 0.05) greater in the group of patients with complications than in those without pancreatitis complications (70.7 +/- 64.4% vs 21.4 +/- 16.2%). Biliary pancreatitis impairs the oxidative-reductive function of the liver proportionally to the degree of hepatic lactic dehydrogenase in the serum. Evaluation of the rate of hepatic elimination of phenazone in the initial stage of this pancreatitis was without prognostic importance for the severity of the disease.

The fatty liver dystrophy (fld) mutation: Developmentally related alterations in hepatic triglyceride metabolism and protein expression

Energy Technology Data Exchange (ETDEWEB)

Reue, K.; Rehnmark, S.; Cohen, R.D.; Leete, T.H.; Doolittle, M.H. [West Los Angeles VA Medical Center, CA (United States). Lipid Research Lab.]|[Univ. of California, Los Angeles, CA (United States). Dept. of Medicine; Giometti, C.S.; Mishler, K. [Argonne National Lab., IL (United States); Slavin, B.G. [Univ. of Southern California, Los Angeles, CA (United States)

1997-07-01

Fatty liver dystrophy (fld) is an autosomal recessive mutation in mice characterized by hypertriglyceridemia and development of a fatty liver in the early neonatal period. Also associated with the fld phenotype is a tissue-specific deficiency in the expression of lipoprotein lipase and hepatic lipase, as well as elevations in hepatic apolipoprotein A-IV and apolipoprotein C-II mRNA levels. Although these lipid abnormalities resolve at the age of weaning, adult mutant mice exhibit a peripheral neuropathy associated with abnormal myelin formation. The fatty liver in fld/fld neonates is characterized by the accumulation of large triglyceride droplets within the parenchymal cells, and these droplets persist within isolated hepatocytes maintained in culture for several days. To identify the metabolic defect that leads to lipid accumulation, the authors investigated several aspects of cellular triglyceride metabolism. The mutant mice exhibited normal activity of acid triacylglycerol lipase, an enzyme thought to be responsible for hydrolysis of dietary triglycerides in the liver. Metabolic labeling studies performed with oleic acid revealed that free fatty acids accumulate in the liver of 3 day old fld/fld mice, but not in adults. This accumulation in liver was mirrored by elevated free fatty acid levels in plasma of fld/fld neonates, with levels highest in very young mice and returning to normal by the age of one month. Quantitation of fatty acid oxidation in cells isolated from fld/fld neonates revealed that oxidation rate is reduced 60% in hepatocytes and 40% in fibroblasts; hepatocytes from adult fld/fld mice exhibited an oxidation rate similar to those from wild-type mice.

Concentration dependence of biotransformation in fish liver S9: Optimizing substrate concentrations to estimate hepatic clearance for bioaccumulation assessment.

Science.gov (United States)

Lo, Justin C; Allard, Gayatri N; Otton, S Victoria; Campbell, David A; Gobas, Frank A P C

2015-12-01

In vitro bioassays to estimate biotransformation rate constants of contaminants in fish are currently being investigated to improve bioaccumulation assessments of hydrophobic contaminants. The present study investigates the relationship between chemical substrate concentration and in vitro biotransformation rate of 4 environmental contaminants (9-methylanthracene, pyrene, chrysene, and benzo[a]pyrene) in rainbow trout (Oncorhynchus mykiss) liver S9 fractions and methods to determine maximum first-order biotransformation rate constants. Substrate depletion experiments using a series of initial substrate concentrations showed that in vitro biotransformation rates exhibit strong concentration dependence, consistent with a Michaelis-Menten kinetic model. The results indicate that depletion rate constants measured at initial substrate concentrations of 1 μM (a current convention) could underestimate the in vitro biotransformation potential and may cause bioconcentration factors to be overestimated if in vitro biotransformation rates are used to assess bioconcentration factors in fish. Depletion rate constants measured using thin-film sorbent dosing experiments were not statistically different from the maximum depletion rate constants derived using a series of solvent delivery-based depletion experiments for 3 of the 4 test chemicals. Multiple solvent delivery-based depletion experiments at a range of initial concentrations are recommended for determining the concentration dependence of in vitro biotransformation rates in fish liver fractions, whereas a single sorbent phase dosing experiment may be able to provide reasonable approximations of maximum depletion rates of very hydrophobic substances. © 2015 SETAC.

Associations between liver 18F fluoro-2-deoxy-D-glucose accumulation and various clinical parameters in a Japanese population. Influence of the metabolic syndrome

International Nuclear Information System (INIS)

Kamimura, Kiyohisa; Nagamachi, Shigeki; Wakamatsu, Hideyuki

2010-01-01

Liver demonstrates a heterogeneous 18 F fluoro-2-deoxy-D-glucose ( 18 F-FDG) uptake pattern and sometimes shows an abnormally increased uptake even when there is no malignant tissue. The aim of this study was to evaluate the relationships of liver 18 F-FDG uptake as related to physical factors, fatty liver, blood glucose (BG), and other biochemical data. 18 F-FDG positron emission tomography (PET) imaging was performed in 101 consecutive subjects for cancer screening. Multiple stepwise regression analysis was used to define the best predictors of the liver standardized uptake value (SUV) among height, weight, waist circumference, body mass index (BMI), systolic and diastolic blood pressure, BG and other biochemical data, id est (i.e.), aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transpeptidase, total cholesterol, high-density lipoprotein cholesterol, triglycerides, total protein, total bilirubin, and alkaline phosphatase. Furthermore, we evaluated the association between liver 18 F-FDG uptake and the metabolic syndrome. The independent factors for increased liver 18 F-FDG uptake (mean SUV >=2) were BMI (P 18 F-FDG uptake. In addition, the liver 18 F-FDG uptake of metabolic syndrome subjects was significantly higher than that of a non-metabolic syndrome subjects. BMI was the strongest determinant of liver 18 F-FDG uptake, and the liver 18 F-FDG uptake of metabolic syndrome subjects was significantly higher than that of non-metabolic syndrome subjects. This result suggests that a subject with a high liver 18 F-FDG uptake should be screened for the metabolic syndrome. (author)

Seaweed supplements normalise metabolic, cardiovascular and liver responses in high-carbohydrate, high-fat fed rats.

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Kumar, Senthil Arun; Magnusson, Marie; Ward, Leigh C; Paul, Nicholas A; Brown, Lindsay

2015-02-02

Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO) and Derbesia tenuissima (DT), in a rat model of human metabolic syndrome. Male Wistar rats (330-340 g) were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium.

Seaweed Supplements Normalise Metabolic, Cardiovascular and Liver Responses in High-Carbohydrate, High-Fat Fed Rats

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Senthil Arun Kumar

2015-02-01

Full Text Available Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO and Derbesia tenuissima (DT, in a rat model of human metabolic syndrome. Male Wistar rats (330–340 g were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium.

Seaweed Supplements Normalise Metabolic, Cardiovascular and Liver Responses in High-Carbohydrate, High-Fat Fed Rats

Science.gov (United States)

Kumar, Senthil Arun; Magnusson, Marie; Ward, Leigh C.; Paul, Nicholas A.; Brown, Lindsay

2015-01-01

Increased seaweed consumption may be linked to the lower incidence of metabolic syndrome in eastern Asia. This study investigated the responses to two tropical green seaweeds, Ulva ohnoi (UO) and Derbesia tenuissima (DT), in a rat model of human metabolic syndrome. Male Wistar rats (330–340 g) were fed either a corn starch-rich diet or a high-carbohydrate, high-fat diet with 25% fructose in drinking water, for 16 weeks. High-carbohydrate, high-fat diet-fed rats showed the signs of metabolic syndrome leading to abdominal obesity, cardiovascular remodelling and non-alcoholic fatty liver disease. Food was supplemented with 5% dried UO or DT for the final 8 weeks only. UO lowered total final body fat mass by 24%, systolic blood pressure by 29 mmHg, and improved glucose utilisation and insulin sensitivity. In contrast, DT did not change total body fat mass but decreased plasma triglycerides by 38% and total cholesterol by 17%. UO contained 18.1% soluble fibre as part of 40.9% total fibre, and increased magnesium, while DT contained 23.4% total fibre, essentially as insoluble fibre. UO was more effective in reducing metabolic syndrome than DT, possibly due to the increased intake of soluble fibre and magnesium. PMID:25648511

Review article: coffee consumption, the metabolic syndrome and non-alcoholic fatty liver disease.

Science.gov (United States)

Yesil, A; Yilmaz, Y

2013-11-01

Coffee consumption may modulate the risk of the metabolic syndrome (MetS) and non-alcoholic fatty liver disease (NAFLD). To review the experimental, epidemiological and clinical studies investigating the association between coffee consumption and the risk of MetS and NAFLD. A literature search was conducted with the aim of finding original experimental, epidemiological and clinical articles on the association between coffee consumption, MetS and NAFLD. The following databases were used: PubMed, Embase, Scopus and Science Direct. We included articles written in English and published up to July 2013. Three experimental animal studies investigated the effects of coffee in the MetS, whereas five examined whether experimental coffee intake may modulate the risk of fatty liver infiltration. All of the animal studies showed a protective effect of coffee towards the development of MetS and NAFLD. Moreover, we identified eleven epidemiological and clinical studies that met the inclusion criteria. Of them, six were carried out on the risk of the MetS and five on the risk of NAFLD. Four of the six studies reported an inverse association between coffee consumption and the risk of MetS. The two studies showing negative results were from the same study cohort consisting of young persons with a low prevalence of the MetS. All of the epidemiological and clinical studies on NAFLD reported a protective effect of coffee intake. Coffee intake can reduce the risk of NAFLD. Whether this effect may be mediated by certain components of the MetS deserves further investigation. © 2013 John Wiley & Sons Ltd.

Changes in serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease

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OU Qiang

2016-12-01

Full Text Available ObjectiveTo investigate the changes in the serum markers of iron metabolism and their clinical significance in patients with nonalcoholic fatty liver disease (NAFLD. MethodsA total of 68 NAFLD patients who were admitted to The Eighth People′s Hospital of Shanghai from July 2014 to April 2016 were enrolled as NAFLD group, and 70 healthy persons who underwent physical examination were enrolled as healthy control group. Among the 68 patients in the NAFLD group, 24 had NAFLD alone and 44 were complicated by abnormal alanine aminotransferase (ALT level. The levels of aspartate aminotransferase (AST, ALT, total cholesterol (TC, triglyceride (TG, and serum markers of iron metabolism ［serum iron (SI, serum ferritin (SF, and serum hepcidin (HEPC］ were measured for all patients, and the correlations between abnormal ALT level and serum markers of iron metabolism were analyzed. The independent samples t-test was used for comparison of continuous data between groups, the chi-square test was used for comparison of categorical data between groups, and the Pearson correlation coefficient was used to investigate the correlation between two variables. ResultsThe NAFLD group had significantly higher body mass index and serum levels of ALT, AST, TC, and TG than the healthy control group (t=9.8, 8.6, 8.5, 9.2, and 2.7, all P＜0.05. Compared with the healthy control group, the NAFLD group had significantly higher levels of SI (21.7±7.1 μmol/L vs 187±6.9 μmol/L, t=2.3, P=0.02 and SF (340.2±257.6 μg/L vs 119.1±81.2 μg/L, t=6.7, P＜0.01 and a significantly lower level of HEPC (12.2±5.3 μg/L vs 22.2±6.5 μg/L, t=9.9, P＜0.01. Compared with those with NAFLD alone, the patients complicated by abnormal ALT level had significantly higher serum levels of ALT (89±58 U/L vs 26±8 U/L, t=7.1, P＜0.01, SI (23.4±6.2 μmol/L vs 19.6±7.9 μmol/L, t=2.2, P=0.03, and SF (406.2±290.0 μg/L vs 219.4±112.0 μg/L, t=3.7, P＜0.01, as well as a significantly

Uric Acid Stimulates Fructokinase and Accelerates Fructose Metabolism in the Development of Fatty Liver

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Lanaspa, Miguel A.; Sanchez-Lozada, Laura G.; Cicerchi, Christina; Li, Nanxing; Roncal-Jimenez, Carlos A.; Ishimoto, Takuji; Le, Myphuong; Garcia, Gabriela E.; Thomas, Jeffrey B.; Rivard, Christopher J.; Andres-Hernando, Ana; Hunter, Brandi; Schreiner, George; Rodriguez-Iturbe, Bernardo; Sautin, Yuri Y.; Johnson, Richard J.

2012-01-01

Excessive dietary fructose intake may have an important role in the current epidemics of fatty liver, obesity and diabetes as its intake parallels the development of these syndromes and because it can induce features of metabolic syndrome. The effects of fructose to induce fatty liver, hypertriglyceridemia and insulin resistance, however, vary dramatically among individuals. The first step in fructose metabolism is mediated by fructokinase (KHK), which phosphorylates fructose to fructose-1-phosphate; intracellular uric acid is also generated as a consequence of the transient ATP depletion that occurs during this reaction. Here we show in human hepatocytes that uric acid up-regulates KHK expression thus leading to the amplification of the lipogenic effects of fructose. Inhibition of uric acid production markedly blocked fructose-induced triglyceride accumulation in hepatocytes in vitro and in vivo. The mechanism whereby uric acid stimulates KHK expression involves the activation of the transcription factor ChREBP, which, in turn, results in the transcriptional activation of KHK by binding to a specific sequence within its promoter. Since subjects sensitive to fructose often develop phenotypes associated with hyperuricemia, uric acid may be an underlying factor in sensitizing hepatocytes to fructose metabolism during the development of fatty liver. PMID:23112875

The Severity of Fatty Liver Disease Relating to Metabolic Abnormalities Independently Predicts Coronary Calcification

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Lee, Ying-Hsiang; Wu, Yih-Jer; Liu, Chuan-Chuan; Hou, Charles Jia-Yin; Yeh, Hung-I.; Tsai, Cheng-Ho; Shih, Shou-Chuan; Hung, Chung-Lieh

2011-01-01

Background. Nonalcoholic fatty liver disease (NAFLD) is one of the metabolic disorders presented in liver. The relationship between severity of NAFLD and coronary atherosclerotic burden remains largely unknown. Methods and Materials. We analyzed subjects undergoing coronary calcium score evaluation by computed tomography (MDCT) and fatty liver assessment using abdominal ultrasonography. Framingham risk score (FRS) and metabolic risk score (MRS) were obtained in all subjects. A graded, semiquantitative score was established to quantify the severity of NAFLD. Multivariate logistic regression analysis was used to depict the association between NAFLD and calcium score. Results. Of all, 342 participants (female: 22.5%, mean age: 48.7 ± 7.0 years) met the sufficient information rendering detailed analysis. The severity of NAFLD was positively associated with MRS (X 2 = 6.12, trend P < 0.001) and FRS (X 2 = 5.88, trend P < 0.001). After multivariable adjustment for clinical variables and life styles, the existence of moderate to severe NAFLD was independently associated with abnormal calcium score (P < 0.05). Conclusion. The severity of NAFLD correlated well with metabolic abnormality and was independently predict coronary calcification beyond clinical factors. Our data suggests that NAFLD based on ultrasonogram could positively reflect the burden of coronary calcification

Metabolic profiling of five flavonoids from Dragon's Blood in human liver microsomes using high-performance liquid chromatography coupled with high resolution mass spectrometry.

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Li, Yujuan; Zhang, Yushi; Wang, Rui; Wei, Lizhong; Deng, Yulin; Ren, Wei

2017-05-01

Although much is known about the pharmacological activities of Dragon's Blood (DB, a traditional Chinese herb), its metabolism in human liver microsomes (HLMs) and the cytochrome P450 (CYP) enzymes has not been studied. This study aims to identify the metabolic profile of five flavonoids (loureirin A, loureirin B, loureirin C, 7,4'-dihydroxyflavone and 5,7,4'-trihydroxyflavanone) from DB in HLMs as well as the CYP enzymes that are involved in the metabolism of them. High-resolution mass spectrometry was used to characterize the structures of their metabolites and 10 cDNA-expressed CYP enzymes (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5) were used to verify which isozymes mediate in the metabolism of the metabolites. Totally, 29 metabolites including 10 metabolites of loureirin A, 10 metabolites of loureirin B, 4 metabolites of loureirin C, 2 metabolites of 7,4'-dihydroxyflavone and 3 metabolites of 5,7,4'-trihydroxyflavanone were elucidated and identified on the basis of the high-resolution MS n data. The metabolic profile of the five flavonoids in HLMs involved hydroxylation, oxidation and demethylation. Among them, hydroxylation was the predominant biotransformation of the five flavonoids in HLMs, occurring in combination with other metabolic reactions. Assay with recombinant P450s revealed that CYP2C9 and CYP2C19 played an important role in the hydroxylation of flavonoids in HLMs. To the best of our knowledge, this is the first in vitro evaluation of the metabolic profile of loureirin A, loureirin B, loureirin C, 7,4'-dihydroxyflavone and 5,7,4'-trihydroxyflavanone in HLMs. Copyright © 2017 Elsevier B.V. All rights reserved.

Strong association between non alcoholic fatty liver disease (NAFLD and low 25(OH vitamin D levels in an adult population with normal serum liver enzymes

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Pozzilli Paolo

2011-07-01

Full Text Available Abstract Background Hypovitaminosis D has been recently recognized as a worldwide epidemic. Since vitamin D exerts significant metabolic activities, comprising free fatty acids (FFA flux regulation from the periphery to the liver, its deficiency may promote fat deposition into the hepatocytes. Aim of our study was to test the hypothesis of a direct association between hypovitaminosis D and the presence of NAFLD in subjects with various degree of insulin-resistance and related metabolic disorders. Methods We studied 262 consecutive subjects referred to the Diabetes and Metabolic Diseases clinics for metabolic evaluation. NAFLD (non-alcoholic fatty liver disease was diagnosed by upper abdomen ultrasonography, metabolic syndrome was identified according to the Third Report of National Cholesterol Education Program/Adult Treatment Panel (NCEP/ATPIII modified criteria. Insulin-resistance was evaluated by means of HOMA-IR. Fatty-Liver-Index, a recently identified correlate of NAFLD, was also estimated. Serum 25(OHvitamin D was measured by colorimetric method. Results Patients with NAFLD (n = 162,61.8% had reduced serum 25(OH vitamin D levels compared to subjects without NAFLD (14.8 ± 9.2 vs 20.5 ± 9.7 ng/ml, p Conclusions Low 25(OHvitamin D levels are associated with the presence of NAFLD independently from metabolic syndrome, diabetes and insulin-resistance profile.

Glycogen metabolism in the liver of Indian desert gerbils (Meriones hurrianae, Jerdon) exposed to internal beta irradiation

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Gupta, N.K.

1996-01-01

Glycogen content and the activities of phosphorylase, glycogen synthetase, phosphohexose isomerase, glucose-6-phosphatase, succinate dehydrogenase, alanine and aspartate aminotransferases have been biochemically determined in the liver of Indian desert gerbils following radiocalcium internal irradiation. Decline in glycogen, phosphohexose isomerase, with a concomitant increase in phosphorylase, succinate dehydrogenase reveals a switch over from glycolytic to oxidative metabolism in liver. Activities of aminotransferases indicate the utilization of transamination products of alanine and aspartate in oxidative pathway during early periods. Transiently increased glucose-6-phosphatase seems to restrict glycogenolytic and glycolytic metabolism and thereby pave way for the acceleration of oxidative metabolism. (author). 52 refs., 2 tabs

Regional metabolic liver function measured in patients with cirrhosis by 2-[¹⁸F]fluoro-2-deoxy-D-galactose PET/CT.

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Sørensen, Michael; Mikkelsen, Kasper S; Frisch, Kim; Villadsen, Gerda E; Keiding, Susanne

2013-06-01

There is a clinical need for methods that can quantify regional hepatic function non-invasively in patients with cirrhosis. Here we validate the use of 2-[(18)F]fluoro-2-deoxy-d-galactose (FDGal) PET/CT for measuring regional metabolic function to this purpose, and apply the method to test the hypothesis of increased intrahepatic metabolic heterogeneity in cirrhosis. Nine cirrhotic patients underwent dynamic liver FDGal PET/CT with blood samples from a radial artery and a liver vein. Hepatic blood flow was measured by indocyanine green infusion/Fick's principle. From blood measurements, hepatic systemic clearance (Ksyst, Lblood/min) and hepatic intrinsic clearance (Vmax/Km, Lblood/min) of FDGal were calculated. From PET data, hepatic systemic clearance of FDGal in liver parenchyma (Kmet, mL blood/mL liver tissue/min) was calculated. Intrahepatic metabolic heterogeneity was evaluated in terms of coefficient-of-variation (CoV, %) using parametric images of Kmet. Mean approximation of Ksyst to Vmax/Km was 86% which validates the use of FDGal as PET tracer of hepatic metabolic function. Mean Kmet was 0.157 mL blood/mL liver tissue/min, which was lower than 0.274 mL blood/mL liver tissue/min, previously found in healthy subjects (pdynamic FDGal PET/CT with arterial sampling provides an accurate measure of regional hepatic metabolic function in patients with cirrhosis. This is likely to have clinical implications for the assessment of patients with liver disease as well as treatment planning and monitoring. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Adipose Tissue Dysfunction and Altered Systemic Amino Acid Metabolism Are Associated with Non-Alcoholic Fatty Liver Disease.

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Sulin Cheng

Full Text Available Fatty liver is a major cause of obesity-related morbidity and mortality. The aim of this study was to identify early metabolic alterations associated with liver fat accumulation in 50- to 55-year-old men (n = 49 and women (n = 52 with and without NAFLD.Hepatic fat content was measured using proton magnetic resonance spectroscopy (1H MRS. Serum samples were analyzed using a nuclear magnetic resonance (NMR metabolomics platform. Global gene expression profiles of adipose tissues and skeletal muscle were analyzed using Affymetrix microarrays and quantitative PCR. Muscle protein expression was analyzed by Western blot.Increased branched-chain amino acid (BCAA, aromatic amino acid (AAA and orosomucoid were associated with liver fat accumulation already in its early stage, independent of sex, obesity or insulin resistance (p<0.05 for all. Significant down-regulation of BCAA catabolism and fatty acid and energy metabolism was observed in the adipose tissue of the NAFLD group (p<0.001for all, whereas no aberrant gene expression in the skeletal muscle was found. Reduced BCAA catabolic activity was inversely associated with serum BCAA and liver fat content (p<0.05 for all.Liver fat accumulation, already in its early stage, is associated with increased serum branched-chain and aromatic amino acids. The observed associations of decreased BCAA catabolism activity, mitochondrial energy metabolism and serum BCAA concentration with liver fat content suggest that adipose tissue dysfunction may have a key role in the systemic nature of NAFLD pathogenesis.

Comparative Analysis of the Relationship between Trichloroethylene Metabolism and Tissue-Specific Toxicity among Inbred Mouse Strains: Liver Effects

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Yoo, Hong Sik; Bradford, Blair U.; Kosyk, Oksana; Shymonyak, Svitlana; Uehara, Takeki; Collins, Leonard B.; Bodnar, Wanda M.; Ball, Louise M.; Gold, Avram; Rusyn, Ivan

2014-01-01

Trichloroethylene (TCE) is a widely used organic solvent. Although TCE is classified as carcinogenic to humans, substantial gaps remain in our understanding of inter-individual variability in TCE metabolism and toxicity, especially in the liver. We tested a hypothesis that amounts of oxidative metabolites of TCE in mouse liver are associated with liver-specific toxicity. Oral dosing with TCE was conducted in sub-acute (600 mg/kg/d; 5 days; 7 inbred mouse strains) and sub-chronic (100 or 400 mg/kg/d; 1, 2, or 4 weeks; 2 inbred mouse strains) designs. We evaluated the quantitative relationship between strain-, dose-, and time-dependent formation of TCE metabolites from cytochrome P450-mediated oxidation [trichloroacetic acid (TCA), dichloroacetic acid (DCA), and trichloroethanol] and glutathione conjugation [S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)glutathione] in serum and liver, and various liver toxicity phenotypes. In sub-acute study, inter-strain variability in TCE metabolite amounts was observed in serum and liver. No induction of Cyp2e1 protein levels in liver was detected. Serum and liver levels of TCA and DCA were correlated with increased transcription of peroxisome proliferator-marker genes Cyp4a10 and Acox1, but not with degree of induction in hepatocellular proliferation. In sub-chronic study, serum and liver levels of oxidative metabolites gradually decreased over time despite continuous dosing. Liver protein levels of Cyp2e1, Adh and Aldh2 were unaffected by treatment with TCE. While the magnitude of induction of peroxisome proliferator-marker genes also declined, hepatocellular proliferation increased. This study offers a unique opportunity to provide a scientific data-driven rationale for some of the major assumptions in human health assessment of TCE. PMID:25424544

A hepatic amino acid/mTOR/S6K-dependent signalling pathway modulates systemic lipid metabolism via neuronal signals.

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Uno, Kenji; Yamada, Tetsuya; Ishigaki, Yasushi; Imai, Junta; Hasegawa, Yutaka; Sawada, Shojiro; Kaneko, Keizo; Ono, Hiraku; Asano, Tomoichiro; Oka, Yoshitomo; Katagiri, Hideki

2015-08-13

Metabolism is coordinated among tissues and organs via neuronal signals. Levels of circulating amino acids (AAs), which are elevated in obesity, activate the intracellular target of rapamycin complex-1 (mTORC1)/S6kinase (S6K) pathway in the liver. Here we demonstrate that hepatic AA/mTORC1/S6K signalling modulates systemic lipid metabolism via a mechanism involving neuronal inter-tissue communication. Hepatic expression of an AA transporter, SNAT2, activates the mTORC1/S6K pathway, and markedly elevates serum triglycerides (TGs), while downregulating adipose lipoprotein lipase (LPL). Hepatic Rheb or active-S6K expression have similar metabolic effects, whereas hepatic expression of dominant-negative-S6K inhibits TG elevation in SNAT2 mice. Denervation, pharmacological deafferentation and β-blocker administration suppress obesity-related hypertriglyceridemia with adipose LPL upregulation, suggesting that signals are transduced between liver and adipose tissue via a neuronal pathway consisting of afferent vagal and efferent sympathetic nerves. Thus, the neuronal mechanism uncovered here serves to coordinate amino acid and lipid levels and contributes to the development of obesity-related hypertriglyceridemia.

Med1 subunit of the mediator complex in nuclear receptor-regulated energy metabolism, liver regeneration, and hepatocarcinogenesis.

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Jia, Yuzhi; Viswakarma, Navin; Reddy, Janardan K

2014-01-01

Several nuclear receptors regulate diverse metabolic functions that impact on critical biological processes, such as development, differentiation, cellular regeneration, and neoplastic conversion. In the liver, some members of the nuclear receptor family, such as peroxisome proliferator-activated receptors (PPARs), constitutive androstane receptor (CAR), farnesoid X receptor (FXR), liver X receptor (LXR), pregnane X receptor (PXR), glucocorticoid receptor (GR), and others, regulate energy homeostasis, the formation and excretion of bile acids, and detoxification of xenobiotics. Excess energy burning resulting from increases in fatty acid oxidation systems in liver generates reactive oxygen species, and the resulting oxidative damage influences liver regeneration and liver tumor development. These nuclear receptors are important sensors of exogenous activators as well as receptor-specific endogenous ligands. In this regard, gene knockout mouse models revealed that some lipid-metabolizing enzymes generate PPARα-activating ligands, while others such as ACOX1 (fatty acyl-CoA oxidase1) inactivate these endogenous PPARα activators. In the absence of ACOX1, the unmetabolized ACOX1 substrates cause sustained activation of PPARα, and the resulting increase in energy burning leads to hepatocarcinogenesis. Ligand-activated nuclear receptors recruit the multisubunit Mediator complex for RNA polymerase II-dependent gene transcription. Evidence indicates that the Med1 subunit of the Mediator is essential for PPARα, PPARγ, CAR, and GR signaling in liver. Med1 null hepatocytes fail to respond to PPARα activators in that these cells do not show induction of peroxisome proliferation and increases in fatty acid oxidation enzymes. Med1-deficient hepatocytes show no increase in cell proliferation and do not give rise to liver tumors. Identification of nuclear receptor-specific coactivators and Mediator subunits should further our understanding of the complexities of metabolic

Coenzyme metabolism in rat liver transketolase

International Nuclear Information System (INIS)

Gorbach, Z.V.; Kubyshin, V.L.; Maglysh, S.S.; Zabrodskaya, S.V.

1987-01-01

On the basis of the results of kinetic investigations, two binding sites for hydroxythiamine diphosphate were determined in apotransketolase, with sharply differing values of K/sub i/: (7-22) x 10 -9 and (13.0-19.7) x 10 -8 M. A study was made of the turnover rate of thiamine diphosphate in holotransketolase in rat liver tissue by a radioisotope method, using [ 14 C] thiamine as the labeled precursor. The half-substitution time and rate constant of degradation of the coenzyme in transketolase are close in absolute values to the analogous indices for the protein portion of the enzyme and constitute 153 h and 0.108 day -1 , respectively. Rat liver transketolase exists in vivo in the form of a substituted α-carbanion. Replacement of thiamine diphosphate by hydroxythiamine diphosphate in the holoenzyme has no effect on the formation of the intermediate α-carbanion form of the enzyme

The Role of Lipid and Lipoprotein Metabolism in Non‐Alcoholic Fatty Liver Disease

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Francesco Massimo Perla

2017-06-01

Full Text Available Due to the epidemic of obesity across the world, nonalcoholic fatty liver disease (NAFLD has become one of the most prevalent chronic liver disorders in children and adolescents. NAFLD comprises a spectrum of fat-associated liver conditions that can result in end-stage liver disease and the need for liver transplantation. Simple steatosis, or fatty liver, occurs early in NAFLD and may progress to nonalcoholic steatohepatitis, fibrosis and cirrhosis with increased risk of hepatocellular carcinoma. The mechanism of the liver injury in NAFLD is currently thought to be a “multiple-hit process” where the first “hit” is an increase in liver fat, followed by multiple additional factors that trigger the inflammatory activity. At the onset of disease, NAFLD is characterized by hepatic triglyceride accumulation and insulin resistance. Liver fat accumulation is associated with increased lipotoxicity from high levels of free fatty acids, free cholesterol and other lipid metabolites. As a consequence, mitochondrial dysfunction with oxidative stress and production of reactive oxygen species and endoplasmic reticulum stress-associated mechanisms, are activated. The present review focuses on the relationship between intra-cellular lipid accumulation and insulin resistance, as well as on lipid and lipoprotein metabolism in NAFLD.

Study on oxidative metabolism of S180 cells induced by meretrix glycopeptide

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Wu, Jielian; Wang, Ping; Kang, Huizhu

2017-03-01

Previous in vitro researches have showed that MGP0501, a natural glycopeptide isolated from Meretrix meretrix, can inhibit proliferation or induce apoptosis in human gastric carcinoma, lung cance (A549), Leukemia K562, mouse melanoma B16, hepatoma or breast cancer cells (MDA-MB-231). In this study, we performed an in vivo study to investigate the anti-tumor effect and mechanisms of MGP0501 on xenografted sarcoma 180 (S180) in mice. Results revealed that the inhibition rates of S180 on solid tumors were 69.72%, with a concentration of 6 mg/kg MGP0501,which was significantly higher than that of CTX. In addition, the biochemical metabolism analysis showed that MGP0501 could enhance the activities of glutathione tablets (GSH-Px) and catalase (CAT) and supersxide dismutase (SOD) in liver of mice. The content of malondialdehyde (MDA) in liver, on the contrary, was decreased. The promotion to antioxidation and the elimination of free radical in liver also attribute the antitumor activity of MGP0501. These results indicated that in vivo antitumor activity is associated with enhanced antioxidant capacity in S180 xenografts-bearing mice.

Dithiobiuret metabolism in the rat

International Nuclear Information System (INIS)

Williams, K.D.; Porter, W.R.; Peterson, R.E.

1982-01-01

Our main objective was to describe the metabolism of dithiobiuret (DTB) in the adult, male rat. Based on the thin-layer chromatographic analysis of urine from animals treated with [ 14 C] or [ 35 S] labeled DTB, two pathways for metabolism are proposed. One pathway is reversible and involves the oxidation of DTB to thiuret and the reduction of thiuret back to DTB. The other pathway consists of the desulfurization of DTB to monothiobiuret. The liver appears to desulfurate DTB because DTB-derived [35S] was eliminated from the liver more rapidly than [ 14 C]. The liver was the only tissue where the elimination kinetics of [ 35 S] and [ 14 C] DTB were different. DTB-derived radioactivity in urine that co-chromatographed with DTB, monothiobiuret, thiuret and sulfate was quantitated along with that of three uncharacterized metabolites. The presence of these unknown metabolites suggests that DTB metabolism is complex. The present study is the first description of the metabolic fate of DTB in the rat and serves as a starting point for determining whether DTB neurotoxicity is caused by the parent compound or a metabolite

Effects of disturbed liver growth and oxidative stress of high-fat diet-fed dams on cholesterol metabolism in offspring mice.

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Kim, Juyoung; Kim, Juhae; Kwon, Young Hye

2016-08-01

Changes in nutritional status during gestation and lactation have detrimental effects on offspring metabolism. Several animal studies have shown that maternal high-fat diet (HFD) can predispose the offspring to development of obesity and metabolic diseases, however the mechanisms underlying these transgenerational effects are poorly understood. Therefore, we examined the effect of maternal HFD consumption on metabolic phenotype and hepatic expression of involved genes in dams to determine whether any of these parameters were associated with the metabolic outcomes in the offspring. Female C57BL/6 mice were fed a low-fat diet (LFD: 10% calories from fat) or a high-fat diet (HFD: 45% calories from fat) for three weeks before mating, and during pregnancy and lactation. Dams and their male offspring were studied at weaning. Dams fed an HFD had significantly higher body and adipose tissue weights and higher serum triglyceride and cholesterol levels than dams fed an LFD. Hepatic lipid levels and mRNA levels of genes involved in lipid metabolism, including LXRα, SREBP-2, FXR, LDLR, and ABCG8 were significantly changed by maternal HFD intake. Significantly lower total liver DNA and protein contents were observed in dams fed an HFD, implicating the disturbed liver adaptation in the pregnancy-related metabolic demand. HFD feeding also induced significant oxidative stress in serum and liver of dams. Offspring of dams fed an HFD had significantly higher serum cholesterol levels, which were negatively correlated with liver weights of dams and positively correlated with hepatic lipid peroxide levels in dams. Maternal HFD consumption induced metabolic dysfunction, including altered liver growth and oxidative stress in dams, which may contribute to the disturbed cholesterol homeostasis in the early life of male mice offspring.

Pyrrolizidine Alkaloids: Metabolic Activation Pathways Leading to Liver Tumor Initiation.

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Fu, Peter P

2017-01-17

Pyrrolizidine alkaloids (PAs) and PA N-oxides are a class of phytochemical carcinogens contained in over 6000 plant species spread around the world. It has been estimated that approximately half of the 660 PAs and PA N-oxides that have been characterized are cytotoxic, genotoxic, and tumorigenic. It was recently determined that a genotoxic mechanism of liver tumor initiation mediated by PA-derived DNA adducts is a common metabolic activation pathway of a number of PAs. We proposed this set of PA-derived DNA adducts could be a common biological biomarker of PA exposure and a potential biomarker of PA-induced liver tumor formation. We have also found that several reactive secondary pyrrolic metabolites can dissociate and interconvert to other secondary pyrrolic metabolites, resulting in the formation of the same exogenous DNA adducts. This present perspective reports the current progress on these new findings and proposes future research needed for obtaining a greater understanding of the role of this activation pathway and validating the use of this set of PA-derived DNA adducts as a biological biomarker of PA-induced liver tumor initiation.

Etiologies of chronic liver disease in children

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Farahmand F

2001-11-01

Full Text Available Chronic Liver diseases in children is the result of many different diseases including: metabolic, genetic, infectious, toxic and idiopathic causes. This was a case series study on 133 infants and children with age range 6 month to 12 years old, who presented clinically with manifestation of chronic liver disease and were admitted to Children Hospital Medical Center from year 1999 to 2000. In this study, 32 (24.5 percent patients had autoimmune chronic hepatitis, 15 (11.3 percent Glycogen storage diseases, 12 (9 percent extrahepatic biliary atresia, 11 (8.2 percent willson disease, 10 (7.5 percent cryptogenic cirrhosis, 6 (4.5 percent chronic hepatitis C, 5 (3.8 percen chronic hepatitic B, 5 (3.8 percent galactosemia 3 (2.25 percent congenital hepatic fibrosis, 3 (3.8 percent histiocytosis X, 3 (2.25 percent sclerosing cholangitis, 2 (1.5 percent byler’s disease 2 (1.5 percent primary tuberculosis, 1 (0.75 percent choledocalcyst, 1 (0.75 percent Alagyle syndrome. According to our data, chronic liver disease should be considered in infants and children. In our study, the most common causes are found to be: metabolic and genetic diseases (37.5 percent, chronic autoimmune hepatitis (24 percent and biliary disorders (14 percent, that encompass 86 percent of the patients.

Molecular modeling used to evaluate CYP2C9-dependent metabolism: homology modeling, molecular dynamics and docking simulations.

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Mendieta-Wejebe, Jessica E; Correa-Basurto, José; García-Segovia, Erika M; Ceballos-Cancino, Gisela; Rosales-Hernández, Martha C

2011-07-01

Cytochrome P450 (CYP) 2C9 is the principal isoform of the CYP2C subfamily in the human liver and is involved in the oxidation of several endogenous and xenobiotic compounds, including many therapeutic drugs. The metabolism of drugs by CYP2C9 can yield either safe or toxic products, which may be related to the recognition and binding modes of the substrates to this isoform. These interactions can be studied using in silico methods such as quantum chemistry, molecular dynamics and docking simulations, which can also be useful for predicting the structure of metabolites. In these types of studies, the ligand and the protein must be tridimensional models; thus, the protein can be built by homology modeling or retrieved from the Protein Data Bank. Therefore, the current review emphasizes the importance of using in silico methods to predict the metabolism of CYP2C9 because these computational tools have allowed the description of the principal characteristics of the active site of this isoform at the molecular level and the chemical properties of its ligands.

Liver upregulation of genes involved in cortisol production and action is associated with metabolic syndrome in morbidly obese patients.

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Torrecilla, Esther; Fernández-Vázquez, Gumersindo; Vicent, David; Sánchez-Franco, Franco; Barabash, Ana; Cabrerizo, Lucio; Sánchez-Pernaute, Andrés; Torres, Antonio J; Rubio, Miguel Angel

2012-03-01

Hepatic 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) activity, which converts cortisone (inactive) to cortisol, is downregulated in obesity. However, this compensation fails in obese with metabolic abnormalities, such as diabetes. To further characterize the tissue-specific cortisol regeneration in obesity, we have investigated the mRNA expression of genes related to local cortisol production, i.e., 11β-HSD1, hexose-6-phosphate dehydrogenase (H6PDH) and cortisol action, glucocorticoid receptor (GR) and a cortisol target gene, phosphoenolpyruvate carboxykinase (PEPCK) in the liver, and visceral (VAT) and subcutaneous (SAT) adipose tissues from morbidly obese patients with and without metabolic syndrome (MS). Fifty morbidly obese patients undergoing bariatric surgery, 14 men (mean age, 41.3 ± 3.5 years; BMI, 48.0 ± 3.6 kg/m(2)) and 36 women (mean age, 44.6 ± 1.9 years; BMI, 44.9 ± 1.2 kg/m(2)), were classified as having MS (MS+, n = 20) or not (MS-, n = 30). Tissue mRNA levels were measured by real-time polymerase chain reaction. Hepatic mRNA levels of these genes were higher in obese patients with MS (11β-HSD1, P = 0.002; H6PDH, P = 0.043; GR, P = 0.033; PEPCK, P = 0.032) and positively correlated with the number of clinical characteristics that define the MS. The expression of the four genes positively correlated among them. In contrast to the liver, these genes were not differently expressed in VAT or SAT, when MS+ and MS- obese patients were compared. Coordinated liver-specific upregulation of genes involved in local cortisol regeneration and action support the concept that local hepatic hypercortisolism contributes to development of MS in morbidly obese patients.

Potential of nor-Ursodeoxycholic Acid in Cholestatic and Metabolic Disorders.

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Trauner, Michael; Halilbasic, Emina; Claudel, Thierry; Steinacher, Daniel; Fuchs, Claudia; Moustafa, Tarek; Pollheimer, Marion; Krones, Elisabeth; Kienbacher, Christian; Traussnigg, Stefan; Kazemi-Shirazi, Lili; Munda, Petra; Hofer, Harald; Fickert, Peter; Paumgartner, Gustav

2015-01-01

24-nor-ursodeoxycholic acid (norUDCA) is a side-chain shortened derivate of ursodeoxycholic acid (UDCA). Since norUDCA is only ineffectively conjugated with glycine or taurine, it has specific physicochemical and therapeutic properties distinct from UDCA. Nonamidated norUDCA undergoes cholehepatic shunting enabling 'ductular targeting' and inducing a bicarbonate-rich hypercholeresis, with cholangioprotective effects. At the same time it has direct anti-inflammatory, antilipotoxic, anti fibrotic, and antiproliferative properties targeting various liver cell populations. norUDCA appears to be one of the most promising novel treatment approaches targeting the liver and the bile duct system at multifactorial and multicellular levels. This review article is a summary of a lecture given at the XXIII International Bile Acid Meeting (Falk Symposium 194) on 'Bile Acids as Signal Integrators and Metabolic Modulators' held in Freiburg, October 8-9, 2014, and summarizes the recent progress with norUDCA as a novel therapeutic approach in cholestatic and metabolic (liver) disorders. 2015 S. Karger AG, Basel.

Effects of Ginkgo biloba extract on free radical metabolism of liver in ...

African Journals Online (AJOL)

This study investigated the effect of Ginkgo biloba extract on Free Radical Metabolism of Liver in mice during endurance exercise. Forty-eight mice were divided into the quiet group and the exercised group. And the two groups were both grouped again, including the control group and the drug-treated group.

Limited value of 18F-FDG PET/CT and S-100B tumour marker in the detection of liver metastases from uveal melanoma compared to liver metastases from cutaneous melanoma

International Nuclear Information System (INIS)

Strobel, K.; Veit-Haibach, P.; Fischer, D.R.; Steinert, Hans C.; Schulthess, G.K. von; Bode, B.; Dummer, R.; Imhof, L.; Goldinger, S.

2009-01-01

The objective of this study was to evaluate the value of 18 F-FDG PET/CT and S-100B tumour marker for the detection of liver metastases from uveal melanoma in comparison to liver metastases from cutaneous melanoma. A retrospective evaluation was conducted of 27 liver metastases in 13 patients with uveal melanoma (UM) (mean age: 56.8, range: 30-77) and 43 liver metastases in 14 patients (mean age: 57.9, range: 40-82) with cutaneous melanoma (CM) regarding size and FDG uptake by measuring the maximum standardized uptake value (SUV max ). S-100B serum tumour markers were available in 20 patients. Cytology, histology, additional morphological imaging and follow-up served as reference standard. In nine patients liver metastases were further evaluated histologically regarding GLUT-1 and S-100 receptor expression and regarding epithelial or spindle cell growth pattern. Of 27 liver metastases in 6 of 13 patients (46%) with UM, 16 (59%) were FDG negative, whereas all liver metastases from CM were positive. Liver metastases from UM showed significantly (p max (mean: 3.5, range: 1.5-13.4) compared with liver metastases from CM (mean: 6.6, range: 2.3-15.3). In four of six (66.7%) patients with UM and liver metastases S-100B was normal and in two (33.3%) increased. All PET-negative liver metastases were detectable by morphological imaging (CT or MRI). S-100B was abnormal in 13 of 14 patients with liver metastases from CM. S-100B values were significantly higher (p = 0.007) in the CM patient group (mean S-100B: 10.9 μg/l, range: 0.1-115 μg/l) compared with the UM patients (mean: 0.2 μg/l, range: 0.0-0.5 μg/l). Histological work-up of the liver metastases showed no obvious difference in GLUT-1 or S-100 expression between UM and CM liver metastases. The minority (36%) of patients with UM had extrahepatic metastases and the majority (86%) of patients with CM had extrahepatic metastases, respectively. There was a close to significant trend to better survival of UM patients

Metabolic activity and mRNA levels of human cardiac CYP450s involved in drug metabolism.

Directory of Open Access Journals (Sweden)

Veronique Michaud

2010-12-01

Full Text Available Tissue-specific expression of CYP450s can regulate the intracellular concentration of drugs and explain inter-subject variability in drug action. The overall objective of our study was to determine in a large cohort of samples, mRNA levels and CYP450 activity expressed in the human heart.CYP450 mRNA levels were determined by RTPCR in left ventricular samples (n = 68 of explanted hearts from patients with end-stage heart failure. Samples were obtained from ischemic and non-ischemic hearts. In some instances (n = 7, samples were available from both the left and right ventricles. A technique for the preparation of microsomes from human heart tissue was developed and CYP450-dependent activity was determined using verapamil enantiomers as probe-drug substrates.Our results show that CYP2J2 mRNA was the most abundant isoform in all human heart left ventricular samples tested. Other CYP450 mRNAs of importance were CYP4A11, CYP2E1, CYP1A1 and CYP2C8 mRNAs while CYP2B6 and CYP2C9 mRNAs were present at low levels in only some of the hearts analyzed. CYP450 mRNAs did not differ between ischemic and non-ischemic hearts and appeared to be present at similar levels in the left and right ventricles. Incubation of verapamil with heart microsomes led to the formation of nine CYP450-dependent metabolites: a major finding was the observation that stereoselectivity was reversed compared to human liver microsomes, in which the R-enantiomer is metabolized to a greater extent.This study determined cardiac mRNA levels of various CYP450 isozymes involved in drug metabolism and demonstrated the prevalent expression of CYP2J2 mRNA. It revealed that cardiomyocytes can efficiently metabolize drugs and that cardiac CYP450s are highly relevant with regard to clearance of drugs in the heart. Our results support the claim that drug metabolism in the vicinity of a drug effector site can modulate drug effects.

Influence of nutrition on liver oxidative metabolism.

Science.gov (United States)

Jorquera, F; Culebras, J M; González-Gallego, J

1996-06-01

The liver plays a major role in the disposition of the majority of drugs. This is due to the presence of several drug-metabolizing enzyme systems, including a group of membrane-bound mixed-function oxidative enzymes, mainly the cytochrome P450 system. Hepatic oxidative capacity can be assessed by changes in antipyrine metabolism. Different drugs and other factors may induce or inhibit the cytochrome P450-dependent system. This effect is important in terms of the efficacy or toxicity of drugs that are substrates for the system. Microsomal oxidation in animals fed with protein-deficient diets is depressed. The mixed-function oxidase activity recovers after a hyperproteic diet or the addition of lipids. Similar findings have been reported in patients with protein-calorie malnutrition, although results in the elderly are conflicting. Different studies have revealed that microsomal oxidation is impaired by total parenteral nutrition and that this effect is absent when changing the caloric source from carbohydrates to a conventional amino acid solution or after lipid addition, especially when administered as medium-chain/long-chain triglyceride mixtures. Peripheral parenteral nutrition appears to increase antipyrine clearance.

A study about the prevalence and the related factors of metabolic syndrome and fatty liver comparing the urban area to tbe industrial area

Energy Technology Data Exchange (ETDEWEB)

Jeong, Hyo Eun; Cho, Pyong Kon [Dept. of of Radiological Science, Catholic University of Daegu. Daegu (Korea, Republic of)

2016-09-15

As the tertiary industry is being developed, many problems are introduced in an industrial area in Korea. This study aims to investigate the residents' health conditions, such as the prevalence of metabolic syndrome and fatty liver diagnosed by ultrasonography, comparing the urban with the industrial areas. The subjects were 378 adults in the urban area and 376 adults in the industrial area. Subject variables accounted for were gender, age, drinking habits, smoking habits, physical activities, waist circumferences and BMI. In blood tests, fasting blood glucose, triglyceride, HDL, blood pressures, total cholesterol, AST, ALT and GGT were examined. Also, the presence and absence of fatty liver, diagnosed using ultrasonography, was investigated. As a result, the prevalence of metabolic syndrome were 43.7% in the urban area and 51.6% in the industrial area, hence it was significantly higher in the industrial area than in the urban area. Fasting blood glucose, triglyceride and waist circumference in the distribution of the individual components were 47.4, 53.7, and 16.1% in the urban area and 54.5, 61.5, and 22.9% in the industrial area respectively, so it was substantially higher in the industrial area than in the urban area. On the other hand, HDL, diastolic blood pressure, and fatty liver were 25.7, 43.4, and 44.7% in the urban area and 21.3, 19.9, and 36.7% in the industrial area respectively and thus it was much higher in the urban area than in the industrial area. In conclusion, this study shows that there were significant differences between the residents' health condition, comparing the urban area to the industrial area. Therefore, the precaution and aggressive management of metabolic syndrome may be necessary, in accordance with the characteristics of the industrial zone.

A study about the prevalence and the related factors of metabolic syndrome and fatty liver comparing the urban area to tbe industrial area

International Nuclear Information System (INIS)

Jeong, Hyo Eun; Cho, Pyong Kon

2016-01-01

As the tertiary industry is being developed, many problems are introduced in an industrial area in Korea. This study aims to investigate the residents' health conditions, such as the prevalence of metabolic syndrome and fatty liver diagnosed by ultrasonography, comparing the urban with the industrial areas. The subjects were 378 adults in the urban area and 376 adults in the industrial area. Subject variables accounted for were gender, age, drinking habits, smoking habits, physical activities, waist circumferences and BMI. In blood tests, fasting blood glucose, triglyceride, HDL, blood pressures, total cholesterol, AST, ALT and GGT were examined. Also, the presence and absence of fatty liver, diagnosed using ultrasonography, was investigated. As a result, the prevalence of metabolic syndrome were 43.7% in the urban area and 51.6% in the industrial area, hence it was significantly higher in the industrial area than in the urban area. Fasting blood glucose, triglyceride and waist circumference in the distribution of the individual components were 47.4, 53.7, and 16.1% in the urban area and 54.5, 61.5, and 22.9% in the industrial area respectively, so it was substantially higher in the industrial area than in the urban area. On the other hand, HDL, diastolic blood pressure, and fatty liver were 25.7, 43.4, and 44.7% in the urban area and 21.3, 19.9, and 36.7% in the industrial area respectively and thus it was much higher in the urban area than in the industrial area. In conclusion, this study shows that there were significant differences between the residents' health condition, comparing the urban area to the industrial area. Therefore, the precaution and aggressive management of metabolic syndrome may be necessary, in accordance with the characteristics of the industrial zone

Differential effect of waterborne cadmium exposure on lipid metabolism in liver and muscle of yellow catfish Pelteobagrus fulvidraco

International Nuclear Information System (INIS)

Chen, Qi-Liang; Gong, Yuan; Luo, Zhi; Zheng, Jia-Lang; Zhu, Qing-Ling

2013-01-01

Highlights: •Cd triggered hepatic lipid accumulation through the improvement of lipogenesis. •Lipid homeostasis in muscle after Cd exposure derived from the down-regulation of both lipogenesis and lipolysis. •Our study determines the mechanism of waterborne Cd exposure on lipid metabolism in fish on a molecular level. •Our study indicates the tissue-specific regulatory effect of lipid metabolism under waterborne Cd exposure. -- Abstract: The present study was conducted to investigate the effect of waterborne cadmium (Cd) exposure on lipid metabolism in liver and muscle of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to 0 (control), 0.49 and 0.95 mg Cd/l, respectively, for 6 weeks, the lipid deposition, Cd accumulation, the activities and expression level of several enzymes as well as the mRNA expression of transcription factors involved in lipid metabolism in liver and muscle were determined. Waterborne Cd exposure reduced growth performance, but increased Cd accumulation in liver and muscle. In liver, lipid content, the activities and the mRNA expression of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), fatty acid synthetase (FAS)) and lipoprotein lipase (LPL) activity increased with increasing waterborne Cd concentrations. However, the mRNA expressions of LPL and peroxisome proliferators-activated receptor (PPAR) α were down-regulated by Cd exposure. Carnitine palmitoyltransferase 1 (CPT1) activity as well as the mRNA expressions of CPT1 and PPARγ showed no significant differences among the treatments. In muscle, lipid contents showed no significant differences among the treatments. The mRNA expression of 6PGD, FAS, CPT1, LPL, PPARα and PPARγ were down-regulated by Cd exposure. Thus, our study indicated that Cd triggered hepatic lipid accumulation through the improvement of lipogenesis, and that lipid homeostasis in muscle was probably conducted by the down

Differential effect of waterborne cadmium exposure on lipid metabolism in liver and muscle of yellow catfish Pelteobagrus fulvidraco

Energy Technology Data Exchange (ETDEWEB)

Chen, Qi-Liang; Gong, Yuan [Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070 (China); Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070 (China); Luo, Zhi, E-mail: luozhi99@mail.hzau.edu.cn [Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070 (China); Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070 (China); Zheng, Jia-Lang; Zhu, Qing-Ling [Key Laboratory of Freshwater Animal Breeding, Ministry of Agriculture of P.R.C., Fishery College, Huazhong Agricultural University, Wuhan 430070 (China); Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan 430070 (China)

2013-10-15

Highlights: •Cd triggered hepatic lipid accumulation through the improvement of lipogenesis. •Lipid homeostasis in muscle after Cd exposure derived from the down-regulation of both lipogenesis and lipolysis. •Our study determines the mechanism of waterborne Cd exposure on lipid metabolism in fish on a molecular level. •Our study indicates the tissue-specific regulatory effect of lipid metabolism under waterborne Cd exposure. -- Abstract: The present study was conducted to investigate the effect of waterborne cadmium (Cd) exposure on lipid metabolism in liver and muscle of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to 0 (control), 0.49 and 0.95 mg Cd/l, respectively, for 6 weeks, the lipid deposition, Cd accumulation, the activities and expression level of several enzymes as well as the mRNA expression of transcription factors involved in lipid metabolism in liver and muscle were determined. Waterborne Cd exposure reduced growth performance, but increased Cd accumulation in liver and muscle. In liver, lipid content, the activities and the mRNA expression of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), fatty acid synthetase (FAS)) and lipoprotein lipase (LPL) activity increased with increasing waterborne Cd concentrations. However, the mRNA expressions of LPL and peroxisome proliferators-activated receptor (PPAR) α were down-regulated by Cd exposure. Carnitine palmitoyltransferase 1 (CPT1) activity as well as the mRNA expressions of CPT1 and PPARγ showed no significant differences among the treatments. In muscle, lipid contents showed no significant differences among the treatments. The mRNA expression of 6PGD, FAS, CPT1, LPL, PPARα and PPARγ were down-regulated by Cd exposure. Thus, our study indicated that Cd triggered hepatic lipid accumulation through the improvement of lipogenesis, and that lipid homeostasis in muscle was probably conducted by the down

Effects of chronic ethanol intake on metabolic conversions of 14C erucic acid by the livers of rat fed with rapeseed or ground nut oil

International Nuclear Information System (INIS)

Lecerf, J.; Bezard, J.

1975-01-01

The effects of addition of ethanol to diets containing rapeseed or ground nut oil on the metabolic conversion of 14 14 C erudic and 9-10 3 H oleic acid were studied in the rat liver. Whatever the diet more 14 C than 3 H radioactivity was recovered in liver lipids 2 and 19 hours after injection of labelled fatty acids. Ethanol has little effect on this incorporation. Only small amounts of 3 H oleic acid were converted. In all cases, the metabolic conversion of erucic acid was identical: the main part of 14 C was not recovered as erucic acid but was present in other mono unsaturated fatty acids n-9:oleic acid (18:1), which was the most labelled acid, 16:1, 20:1 and nervonic acid (24:1). The amount of erucic acid converted to shorter chain fatty acids was unchanged by addition of ethanol but the alcohol increased the proportion of 14 C radioactivity recovered as nervonic acid. This latter effect was opposite to the effect of rapeseed oil diet, which consisted in a decrease in the conversion of erucic to nervonic acid. A high amount of 14 C radioactivity was recovered in the F.F.A. fraction of the liver as an unknown compound (13 and 80% of 14 C radioacitivty respectively after 2 and 19h). Its identification is presently under investigation [fr

Use of external metabolizing systems when testing for endocrine disruption in the T-screen assay

International Nuclear Information System (INIS)

Taxvig, Camilla; Olesen, Pelle Thonning; Nellemann, Christine

2011-01-01

Although, it is well-established that information on the metabolism of a substance is important in the evaluation of its toxic potential, there is limited experience with incorporating metabolic aspects into in vitro tests for endocrine disrupters. The aim of the current study was a) to study different in vitro systems for biotransformation of ten known endocrine disrupting chemicals (EDs): five azole fungicides, three parabens and 2 phthalates, b) to determine possible changes in the ability of the EDs to bind and activate the thyroid receptor (TR) in the in vitro T-screen assay after biotransformation and c) to investigate the endogenous metabolic capacity of the GH3 cells, the cell line used in the T-screen assay, which is a proliferation assay used for the in vitro detection of agonistic and antagonistic properties of compounds at the level of the TR. The two in vitro metabolizing systems tested the human liver S9 mix and the PCB-induced rat microsomes gave an almost complete metabolic transformation of the tested parabens and phthalates. No marked difference the effects in the T-screen assay was observed between the parent compounds and the effects of the tested metabolic extracts. The GH3 cells themselves significantly metabolized the two tested phthalates dimethyl phthalate (DMP) and diethyl phthalate (DEP). Overall the results and qualitative data from the current study show that an in vitro metabolizing system using liver S9 or microsomes could be a convenient method for the incorporation of metabolic and toxicokinetic aspects into in vitro testing for endocrine disrupting effects.

Celastrol ameliorates liver metabolic damage caused by a high-fat diet through Sirt1

Directory of Open Access Journals (Sweden)

Yinliang Zhang

2017-01-01

. Conclusions: Celastrol ameliorates NAFLD by decreasing lipid synthesis and improving the anti-oxidative and anti-inflammatory status. And Sirt1 has an important role in Celastrol-ameliorating liver metabolic damage caused by HFD. Keywords: Nonalcoholic fatty liver disease, Celastrol, Sirt1, Lipid metabolism, Chronic inflammation, Oxidative stress

Quantitative proteomics analysis reveals perturbation of lipid metabolic pathways in the liver of Atlantic cod (Gadus morhua) treated with PCB 153.

Science.gov (United States)

Yadetie, Fekadu; Oveland, Eystein; Døskeland, Anne; Berven, Frode; Goksøyr, Anders; Karlsen, Odd André

2017-04-01

PCB 153 is one of the most abundant PCB congeners detected in biological samples. It is a persistent compound that is still present in the environment despite the ban on production and use of PCBs in the late 1970s. It has strong tendencies to bioaccumulate and biomagnify in biota, and studies have suggested that it is an endocrine and metabolic disruptor. In order to study mechanisms of toxicity, we exposed Atlantic cod (Gadus morhua) to various doses of PCB 153 (0, 0.5, 2 and 8mg/kg body weight) for two weeks and examined the effects on expression of liver proteins using label-free quantitative proteomics. Label-free liquid chromatography-mass spectrometry analysis of the liver proteome resulted in the quantification of 1272 proteins, of which 78 proteins were differentially regulated in the PCB 153-treated dose groups compared to the control group. Functional enrichment analysis showed that pathways significantly affected are related to lipid metabolism, cytoskeletal remodeling, cell cycle and cell adhesion. Importantly, the main effects appear to be on lipid metabolism, with up-regulation of enzymes in the de novo fatty acid synthesis pathway, consistent with previous transcriptomics results. Increased plasma triglyceride levels were also observed in the PCB 153 treated fish, in agreement with the induction of the lipogenic genes and proteins. The results suggest that PCB 153 perturbs lipid metabolism in the Atlantic cod liver. Elevated levels of lipogenic enzymes and plasma triglycerides further suggest increased synthesis of fatty acids and triglycerides. Copyright © 2017 Elsevier B.V. All rights reserved.

Energy metabolism and biotransformation as endpoints to pre-screen hepatotoxicity using a liver spheroid model

International Nuclear Information System (INIS)

Xu Jinsheng; Purcell, Wendy M.

2006-01-01

The current study investigated liver spheroid culture as an in vitro model to evaluate the endpoints relevant to the status of energy metabolism and biotransformation after exposure to test toxicants. Mature rat liver spheroids were exposed to diclofenac, galactosamine, isoniazid, paracetamol, m-dinitrobenzene (m-DNB) and 3-nitroaniline (3-NA) for 24 h. Pyruvate uptake, galactose biotransformation, lactate release and glucose secretion were evaluated after exposure. The results showed that pyruvate uptake and lactate release by mature liver spheroids in culture were maintained at a relatively stable level. These endpoints, together with glucose secretion and galactose biotransformation, were related to and could reflect the status of energy metabolism and biotransformation in hepatocytes. After exposure, all of the test agents significantly reduced glucose secretion, which was shown to be the most sensitive endpoint of those evaluated. Diclofenac, isoniazid, paracetamol and galactosamine reduced lactate release (P < 0.01), but m-DNB increased lactate release (P < 0.01). Diclofenac, isoniazid and paracetamol also reduced pyruvate uptake (P < 0.01), while galactosamine had little discernible effect. Diclofenac, galactosamine, paracetamol and m-DNB also reduced galactose biotransformation (P < 0.01), by contrast, isoniazid did not. The metabolite of m-DNB, 3-NA, which served as a negative control, did not cause significant changes in lactate release, pyruvate uptake or galactose biotransformation. It is concluded that pyruvate uptake, galactose biotransformation, lactate release and glucose secretion can be used as endpoints for evaluating the status of energy metabolism and biotransformation after exposure to test agents using the liver spheroid model to pre-screen hepatotoxicity

Intestinal first pass metabolism of midazolam in liver cirrhosis --effect of grapefruit juice

DEFF Research Database (Denmark)

Andersen, Vibeke; Pedersen, Natalie; Larsen, Niels-Erik

2002-01-01

Grapefruit juice inhibits CYP3A4 in the intestinal wall leading to a reduced intestinal first pass metabolism and thereby an increased oral bioavailability of certain drugs. For example, it has been shown that the oral bioavailability of midazolam, a CYP3A4 substrate, increased by 52% in healthy...... subjects after ingestion of grapefruit juice. However, this interaction has not been studied in patients with impaired liver function. Accordingly, the effect of grapefruit juice on the AUC of midazolam and the metabolite alpha-hydroxymidazolam was studied in patients with cirrhosis of the liver....

S-Adenosylmethionine attenuates bile duct early warm ischemia reperfusion injury after rat liver transplantation.

Science.gov (United States)

Tang, Yong; Chu, Hongpeng; Cao, Guojun; Du, Xiaolong; Min, Xiaobo; Wan, Chidan

2018-03-01

Warm ischemia reperfusion injury (IRI) plays a key role in biliary complication, which is a substantial vulnerability of liver transplantation. The early pathophysiological changes of IRI are characterized by an excessive inflammatory response. S-Adenosylmethionine (SAM) is an important metabolic intermediate that modulates inflammatory reactions; however, its role in bile duct warm IRI is not known. In this study, male rats were treated with or without SAM (170 μmol/kg body weight) after orthotopic autologous liver transplantation. The histopathological observations showed that bile duct injury in the IRI group was more serious than in the SAM group. The alanine aminotransferase (ALT), alkaline phosphatase (ALP) and direct bilirubin (DBIL) levels in the serum of the IRI group were significantly increased compared to the SAM group (P liver and bile duct tissues, down-regulated TNF-α levels and up-regulated IL-10 expression in bile duct tissues compared to the IRI group (P livers were much higher compared to those in SAM-treated rats at 24 h after liver transplantation (P bile ducts against warm IRI by suppressing oxidative stress, inflammatory reactions and apoptosis of biliary epithelial cells after liver transplantation.α. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effects of castration on expression of lipid metabolism genes in the liver of korean cattle.

Science.gov (United States)

Baik, Myunggi; Nguyen, Trang Hoa; Jeong, Jin Young; Piao, Min Yu; Kang, Hyeok Joong

2015-01-01

Castration induces the accumulation of body fat and deposition of intramuscular fat in Korean cattle, resulting in improved beef quality. However, little is known about the metabolic adaptations in the liver following castration. To understand changes in lipid metabolism following castration, hepatic expression levels of lipid metabolism genes were compared between Korean bulls and steers. Steers had higher (pcastration of bulls. However, we found no differences in the hepatic expression levels of genes related to triglyceride synthesis (mitochondrial glycerol-3-phosphate acyltransferase, diacylglycerol O-acyltransferase 1 and 2) and fatty acid (FA) oxidation (carnitine palmitoyltransferase 1A, C-4 to C-12 straight chain acyl-CoA dehydrogenase, very long chain acyl-CoA dehydrogenase) between bulls and steers. No differences in gene expression for very-low-density lipoprotein (VLDL) secretion, including apolipoprotein B mRNA and microsomal triglyceride transfer protein (MTTP) protein, were observed in the liver although MTTP mRNA levels were higher in steers compared to bulls. In conclusion, FA synthesis may contribute to increased hepatic lipid deposition in steers following castration. However, hepatic lipid metabolism, including triglyceride synthesis, FA oxidation, and VLDL secretion, was not significantly altered by castration. Our results suggest that hepatic lipid metabolism does not significantly contribute to increased body fat deposition in steers following castration.

Non-alcoholic and alcoholic Fatty Liver Disease - two Diseases of Affluence associated with the Metabolic Syndrome and Type 2 Diabetes: the FIN-D2D Survey

Directory of Open Access Journals (Sweden)

Saltevo Juha

2010-05-01

Full Text Available Abstract Background Non-alcoholic fatty liver disease (NAFLD is known to be associated with the metabolic syndrome (MetS and abnormal glucose tolerance. Whether alcoholic fatty liver disease (AFLD is associated with similar metabolic abnormalities has not been examined in a population-based study. We aimed at assessing the prevalences of NAFLD and AFLD, and to examine to what extent these conditions are associated with MetS and abnormal glucose tolerance. Methods The cohort included 2766 Finnish subjects (45-74 years from the population-based FIN-D2D survey. Features of insulin resistance, components of the MetS, glucose tolerance status by oral glucose tolerance test, serum liver enzyme concentrations, and daily alcohol consumption were assessed. Results Subjects with NAFLD and AFLD were equally obese and had similar fasting and insulin concentrations. The prevalences of NAFLD and AFLD were 21% (95% CI: 19%-22% and 7% (95% CI: 6%-8%. The MetS was slightly more prevalent in AFLD (73% than in NAFLD (70%, p = 0.028, and type 2 diabetes was similarly prevalent in NAFLD and AFLD (24-25%. The MetS and type 2 diabetes were more prevalent in subjects with NAFLD or AFLD compared to subjects with normal LFTs (53% and 14%, p Discussion and conclusion In Finnish middle-aged population, the prevalence of NAFLD is 3-fold higher than that of AFLD. The prevalences of MetS and type 2 diabetes are, however, significantly increased in both NAFLD and AFLD compared to subjects with normal LFTs. Subjects with AFLD are thus similarly metabolically unhealthy as subjects with NAFLD.

Systemic responses to inhaled ozone in mice: cachexia and down-regulation of liver xenobiotic metabolizing genes

Energy Technology Data Exchange (ETDEWEB)

Last, Jerold A [Pulmonary and Critical Care Medicine, School of Medicine, Toxic Substances Program, 1131 Surge I, University of California, Davis, CA 95616-8723 (United States); Gohil, Kishorchandra [Pulmonary and Critical Care Medicine, School of Medicine, Toxic Substances Program, 1131 Surge I, University of California, Davis, CA 95616-8723 (United States); Mathrani, Vivek C [Pulmonary and Critical Care Medicine, School of Medicine, Toxic Substances Program, 1131 Surge I, University of California, Davis, CA 95616-8723 (United States); Kenyon, Nicholas J [Pulmonary and Critical Care Medicine, School of Medicine, Toxic Substances Program, 1131 Surge I, University of California, Davis, CA 95616-8723 (United States)

2005-10-15

Rats or mice acutely exposed to high concentrations of ozone show an immediate and significant weight loss, even when allowed free access to food and water. The mechanisms underlying this systemic response to ozone have not been previously elucidated. We have applied the technique of global gene expression analysis to the livers of C57BL mice acutely exposed to ozone. Mice lost up to 14% of their original body weight, with a 42% decrease in total food consumption. We previously had found significant up-regulation of genes encoding proliferative enzymes, proteins related to acute phase reactions and cytoskeletal functions, and other biomarkers of a cachexia-like inflammatory state in lungs of mice exposed to ozone. These results are consistent with a general up-regulation of different gene families responsive to NF-{kappa}B in the lungs of the exposed mice. In the present study, we observed significant down-regulation of different families of mRNAs in the livers of the exposed mice, including genes related to lipid and fatty acid metabolism, and to carbohydrate metabolism in this tissue, consistent with a systemic cachexic response. Several interferon-dependent genes were down-regulated in the liver, suggesting a possible role for interferon as a signaling molecule between lung and liver. In addition, transcription of several mRNAs encoding enzymes of xenobiotic metabolism in the livers of mice exposed to ozone was decreased, suggesting cytokine-mediated suppression of cytochrome P450 expression. This finding may explain a previously controversial report from other investigators more than 20 years ago of prolongation of pentobarbital sleeping time in mice exposed to ozone.

Systemic responses to inhaled ozone in mice: cachexia and down-regulation of liver xenobiotic metabolizing genes

International Nuclear Information System (INIS)

Last, Jerold A.; Gohil, Kishorchandra; Mathrani, Vivek C.; Kenyon, Nicholas J.

2005-01-01

Rats or mice acutely exposed to high concentrations of ozone show an immediate and significant weight loss, even when allowed free access to food and water. The mechanisms underlying this systemic response to ozone have not been previously elucidated. We have applied the technique of global gene expression analysis to the livers of C57BL mice acutely exposed to ozone. Mice lost up to 14% of their original body weight, with a 42% decrease in total food consumption. We previously had found significant up-regulation of genes encoding proliferative enzymes, proteins related to acute phase reactions and cytoskeletal functions, and other biomarkers of a cachexia-like inflammatory state in lungs of mice exposed to ozone. These results are consistent with a general up-regulation of different gene families responsive to NF-κB in the lungs of the exposed mice. In the present study, we observed significant down-regulation of different families of mRNAs in the livers of the exposed mice, including genes related to lipid and fatty acid metabolism, and to carbohydrate metabolism in this tissue, consistent with a systemic cachexic response. Several interferon-dependent genes were down-regulated in the liver, suggesting a possible role for interferon as a signaling molecule between lung and liver. In addition, transcription of several mRNAs encoding enzymes of xenobiotic metabolism in the livers of mice exposed to ozone was decreased, suggesting cytokine-mediated suppression of cytochrome P450 expression. This finding may explain a previously controversial report from other investigators more than 20 years ago of prolongation of pentobarbital sleeping time in mice exposed to ozone

Hepatic injury induces contrasting response in liver and kidney to chemicals that are metabolically activated: Role of male sex hormone

International Nuclear Information System (INIS)

Kim, Young C.; Yim, Hye K.; Jung, Young S.; Park, Jae H.; Kim, Sung Y.

2007-01-01

Injury to liver, resulting in loss of its normal physiological/biochemical functions, may adversely affect a secondary organ. We examined the response of the liver and kidney to chemical substances that require metabolic activation for their toxicities in mice with a preceding liver injury. Carbon tetrachloride treatment 24 h prior to a challenging dose of carbon tetrachloride or acetaminophen decreased the resulting hepatotoxicity both in male and female mice as determined by histopathological examination and increases in serum enzyme activities. In contrast, the renal toxicity of the challenging toxicants was elevated markedly in male, but not in female mice. Partial hepatectomy also induced similar changes in the hepatotoxicity and nephrotoxicity of a challenging toxicant, suggesting that the contrasting response of male liver and kidney was associated with the reduction of the hepatic metabolizing capacity. Carbon tetrachloride pretreatment or partial hepatectomy decreased the hepatic xenobiotic-metabolizing enzyme activities in both sexes but elevated the renal p-nitrophenol hydroxylase, p-nitroanisole O-demethylase and aminopyrine N-demethylase activities significantly only in male mice. Increases in Cyp2e1 and Cyp2b expression were also evident in male kidney. Castration of males or testosterone administration to females diminished the sex-related differences in the renal response to an acute liver injury. The results indicate that reduction of the hepatic metabolizing capacity induced by liver injury may render secondary target organs susceptible to chemical substances activated in these organs. This effect may be sex-specific. It is also suggested that an integrated approach should be taken for proper assessment of chemical hazards

Adipose Tissue Dysfunction and Altered Systemic Amino Acid Metabolism Are Associated with Non-Alcoholic Fatty Liver Disease

NARCIS (Netherlands)

Cheng, Sulin; Wiklund, Petri; Autio, Reija; Borra, Ronald; Ojanen, Xiaowei; Xu, Leiting; Törmäkangas, Timo; Alen, Markku

2015-01-01

BACKGROUND: Fatty liver is a major cause of obesity-related morbidity and mortality. The aim of this study was to identify early metabolic alterations associated with liver fat accumulation in 50- to 55-year-old men (n = 49) and women (n = 52) with and without NAFLD. METHODS: Hepatic fat content was

Transcriptome Analyses Reveal Lipid Metabolic Process in Liver Related to the Difference of Carcass Fat Content in Rainbow Trout (Oncorhynchus mykiss

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Guo Hu

2016-01-01

Full Text Available Excessive accumulation of carcass fat in farm animals, including fish, has a significant impact on meat quality and on the cost of feeding. Similar to farmed animals and humans, the liver can be considered one of the most important organs involved in lipid metabolism in rainbow trout (Oncorhynchus mykiss. RNA-seq based whole transcriptome sequencing was performed to liver tissue of rainbow trout with high and low carcass fat content in this study. In total 1,694 differentially expressed transcripts were identified, including many genes involved in lipid metabolism, such as L-FABP, adiponectin, PPAR-α, PPAR-β, and IGFBP1a. Evidence presented in this study indicated that lipid metabolic process in liver may be related to the difference of carcass fat content. The relevance of PPAR-α and PPAR-β as molecular markers for fat storage in liver should be worthy of further investigation.

Liver X receptor antagonist reduces lipid formation and increases glucose metabolism in myotubes from lean, obese and type 2 diabetic individuals

DEFF Research Database (Denmark)

Kase, E T; Thoresen, G H; Westerlund, S

2007-01-01

AIMS/HYPOTHESIS: Liver X receptors (LXRs) play important roles in lipid and carbohydrate metabolism. The purpose of the present study was to evaluate effects of the endogenous LXR agonist 22-R-hydroxycholesterol (22-R-HC) and its stereoisomer 22-S-hydroxycholesterol (22-S-HC), in comparison...... with the synthetic agonist T0901317 on lipid and glucose metabolism in human skeletal muscle cells (myotubes). METHODS: Myotubes established from lean and obese control volunteers and from obese type 2 diabetic volunteers were treated with LXR ligands for 4 days. Lipid and glucose metabolisms were studied...... with labelled precursors, and gene expression was analysed using real-time PCR. RESULTS: Treatment with T0901317 increased lipogenesis (de novo lipid synthesis) and lipid accumulation in myotubes, this increase being more pronounced in myotubes from type 2 diabetic volunteers than from lean volunteers...

In vitro metabolism of the anti-androgenic fungicide vinclozolin by rat liver microsomes.

Science.gov (United States)

Sierra-Santoyo, Adolfo; Angeles-Soto, Esperanza; de Lourdes López-González, Ma; Harrison, Randy A; Hughes, Michael F

2012-03-01

Vinclozolin (V) is a fungicide used in agricultural settings. V administered to rats is hydrolyzed to 2-[[(3,5-dichlorophenyl)-carbamoyl]oxy]-2-methyl-3-butenoic acid (M1) and 3',5'-dichloro-2-hydroxy-2-methylbut-3-enanilide (M2). V, M1 and M2 have antiandrogenic properties by interacting with the androgen receptor. Data on V, M1 and M2 biotransformation are limited. Our objective was to characterize V metabolism by rat liver microsomes. V was incubated with non-treated adult male Long-Evans rat liver microsomes and NADPH. Several metabolites were detected following the extraction of incubate with acetonitrile and analysis by HPLC/DAD/MSD. One metabolite was identified as [3-(3,5-dichlorophenyl)-5-methyl-5-(1,2-dihydroxyethyl)-1,3-oxazolidine-2,4-dione] (M4), which was gradually converted to 3',5'-dichloro-2,3,4-trihydroxy-2-methylbutylanilide (M5). Both co-eluted in the same HPLC peak. Another metabolite ([M7]) was detected by UV but was unstable for mass spectral analysis. The K(M app) for co-eluted M4/M5 and [M7] was 53.7 and 135.4 μM, the V(max app) was 0.812 and 0.669 nmoles/min/mg protein, and CL(int) was 15.1 and 4.9 ml/min/g protein, respectively. Pilocarpine, orphenadrine and proadifen and anti-rat cytochrome P450 (CYP)2A, 2B and 3A antibodies inhibited M4/M5 and [M7] formation. These results indicate that V is efficiently metabolized by CYP. Determination of the metabolites of V will provide further insight into the relationship between toxicity and tissue dose of V and its metabolites.

Monkey liver cytochrome P450 2C19 is involved in R- and S-warfarin 7-hydroxylation.

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Hosoi, Yoshio; Uno, Yasuhiro; Murayama, Norie; Fujino, Hideki; Shukuya, Mitsunori; Iwasaki, Kazuhide; Shimizu, Makiko; Utoh, Masahiro; Yamazaki, Hiroshi

2012-12-15

Cynomolgus monkeys are widely used as primate models in preclinical studies. However, some differences are occasionally seen between monkeys and humans in the activities of cytochrome P450 enzymes. R- and S-warfarin are model substrates for stereoselective oxidation in humans. In this current research, the activities of monkey liver microsomes and 14 recombinantly expressed monkey cytochrome P450 enzymes were analyzed with respect to R- and S-warfarin 6- and 7-hydroxylation. Monkey liver microsomes efficiently mediated both R- and S-warfarin 7-hydroxylation, in contrast to human liver microsomes, which preferentially catalyzed S-warfarin 7-hydroxylation. R-Warfarin 7-hydroxylation activities in monkey liver microsomes were not inhibited by α-naphthoflavone or ketoconazole, and were roughly correlated with P450 2C19 levels and flurbiprofen 4-hydroxylation activities in microsomes from 20 monkey livers. In contrast, S-warfarin 7-hydroxylation activities were not correlated with the four marker drug oxidation activities used. Among the 14 recombinantly expressed monkey P450 enzymes tested, P450 2C19 had the highest activities for R- and S-warfarin 7-hydroxylations. Monkey P450 3A4 and 3A5 slowly mediated R- and S-warfarin 6-hydroxylations. Kinetic analysis revealed that monkey P450 2C19 had high V(max) and low K(m) values for R-warfarin 7-hydroxylation, comparable to those for monkey liver microsomes. Monkey P450 2C19 also mediated S-warfarin 7-hydroxylation with V(max) and V(max)/K(m) values comparable to those for recombinant human P450 2C9. R-warfarin could dock favorably into monkey P450 2C19 modeled. These results collectively suggest high activities for monkey liver P450 2C19 toward R- and S-warfarin 6- and 7-hydroxylation in contrast to the saturation kinetics of human P450 2C9-mediated S-warfarin 7-hydroxylation. Copyright © 2012 Elsevier Inc. All rights reserved.

The metabolism of 32P-CP-PLLA seed implanted in the liver and its damage to the normal liver tissue: a study in the experimental dogs

International Nuclear Information System (INIS)

Tan Zhongbao; Liu Lu; Guo Jinhe; Zhu Guangyu; Wang Fuan; Nie Qi; Gao Hailin; Teng Gaojun

2010-01-01

Objective: To investigate the effects of intratumoral implantation of 32 P -CP-PLLA seeds on the normal canine liver tissue and to explore the metabolism of 32 P-CP-PLLA seeds implanted in the liver of experimental dogs. Methods: Twelve beagles were enrolled in this study. The dogs were randomly and equally divided into four groups: group A (185 MBq), group B (370 MBq), group C (740 MBq) and group D (0 MBq). By using laparotomy procedure 32 P-CP-PLLA seeds were implanted into dog's liver. CT scan was performed before operation as well as before the dog was sacrificed. All dogs were sacrificed three months after the implantation. Before the procedure and 1, 2, 4, 8 and 12 weeks after the procedure the blood tests and serum biochemical tests were conducted. One dog from group B and group C was selected respectively and was fed in a metabolic cage. Within one month after the procedure the cpm in feces and in urine was determined every 24 hours. One dog was picked out from each of the three groups and was punctured to get its liver tissue for pathologic exam each time at 1, 2, 4, 8 and 12 weeks after the implantation, and SPECT imaging was also performed at the same time. Pathologic study, both macroscopic and microscopic (including optical and electronic microscopy) was made to observe the liver damage after the dog was sacrificed. The statistical analysis was processed by using SPSS 13.0 software and the measuring data were expressed with mean ± standard deviation (x ± s). Results: Two months after the procedure, serological examination found that the serum alkaline phosphatase (BKP) in both group B and group C was significantly higher than that in other groups, the difference was statistically significant (P 32 P-CP-PLLA seeds was manifested as a spherical lesion which was encysted by a layer of fibrous tissue with an edematous zone peripherally. Conclusion: The implantation of 32 P-CP-PLLA seeds in dog's liver causes only localized hepatic damage with no general

Tc-99 m-GSA liver scintigraphy in alcoholic liver cirrhosis

International Nuclear Information System (INIS)

Itano, Satoshi; Harada, Masaru; Nagamatsu, Hiroaki

2003-01-01

We compared 15 alcoholic liver cirrhosis patients with 10 viral liver cirrhosis patients using technetium-99 m-galactosyl human serum albumin (Tc-99 m-GSA) liver scintigraphy and could clinically reveal the disorder of metabolism of asialoglycoprotein in alcoholic liver cirrhosis. Receptor index (LHL 15 = liver count divided by the sum of liver and heart counts at 15 minutes) was significantly (p <0.01) lower in patients with alcoholic cirrhosis (median: 0.821), compared with patients with viral cirrhosis (0.915). Grading score, which was an index showed by the difference in the isotope uptake patterns between liver and heart, was significantly (p <0.01) worse in patients with alcoholic cirrhosis, compared with patients with viral cirrhosis. These results suggested that alcoholic liver cirrhosis had a specific disorder of a metabolic function for asialoglycoprotein. (author)

Radioprotection of whole-body gamma irradiation induced alterations in lipid metabolism of liver and plasma by AET (S-2, aminoethyl isothiuronium Br. H. Br.) and serotonin in rats

International Nuclear Information System (INIS)

Ramanathan, R.; Misra, U.K.

1975-01-01

Radioprotective effect of AET, serotonin and their mixture has been studied on liver and plasma lipid metabolism 24 hrs and 48 hrs after irradiation in fasted male rats. AET and serotonin both gave significant radioprotection to certain liver and plasma lipid components, but the mixture of the two afforded a better protection. The non-radioprotection of plasma NEFA, phospholipids and phosphatidyl choline levels by serotonin observed in irradiated rats was because serotonin itself raised the levels of these lipids in control rats. Serotonin alone or in mixture effectively protected the radiation-induced increased incorporation of NaH 2 32 PO 4 into liver phospholipids. Mixture of AET and serotonin failed to protect the increased incorporation of aceae-1-14-C into liver total fatty acids and cholesterol, but it prevented this increased incorporation into liver triglycerides and phospholipids. (orig.) [de

Dietary Omega-3 Fatty Acid Deficiency and High Fructose Intake in the Development of Metabolic Syndrome, Brain Metabolic Abnormalities, and Non-Alcoholic Fatty Liver Disease

Directory of Open Access Journals (Sweden)

Artemis P. Simopoulos

2013-07-01

Full Text Available Western diets are characterized by both dietary omega-3 fatty acid deficiency and increased fructose intake. The latter found in high amounts in added sugars such as sucrose and high fructose corn syrup (HFCS. Both a low intake of omega-3 fatty acids or a high fructose intake contribute to metabolic syndrome, liver steatosis or non-alcoholic fatty liver disease (NAFLD, promote brain insulin resistance, and increase the vulnerability to cognitive dysfunction. Insulin resistance is the core perturbation of metabolic syndrome. Multiple cognitive domains are affected by metabolic syndrome in adults and in obese adolescents, with volume losses in the hippocampus and frontal lobe, affecting executive function. Fish oil supplementation maintains proper insulin signaling in the brain, ameliorates NAFLD and decreases the risk to metabolic syndrome suggesting that adequate levels of omega-3 fatty acids in the diet can cope with the metabolic challenges imposed by high fructose intake in Western diets which is of major public health importance. This review presents the current status of the mechanisms involved in the development of the metabolic syndrome, brain insulin resistance, and NAFLD a most promising area of research in Nutrition for the prevention of these conditions, chronic diseases, and improvement of Public Health.

Nutrition and Liver Health.

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Jackson, Alan A

2017-01-01

that would enable a more precise nutritional diagnosis, but these require systematic investigation and application. For the present, approaches that place emphasis on being able to control the metabolic state without exposing the liver to unnecessary metabolic stress remain the basis for successful nutritional support. © 2017 S. Karger AG, Basel.

Clinical features of male patients with alcoholic liver cirrhosis or hepatitis B cirrhosis complicated by abnormal glucose metabolism

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CHEN Qidan

2016-02-01

Full Text Available ObjectiveTo investigate the clinical features of male patients with alcoholic liver cirrhosis (ALC or hepatitis B cirrhosis (HBC complicated by abnormal glucose metabolism. MethodsA total of 287 patients with liver cirrhosis who were admitted to Guangzhou Panyu Central Hospital from January 2008 to September 2013 were selected. Among these patients, 74 had ALC and were all male, including 54 with abnormal glucose metabolism; the other 213 had HBC, including 97 with abnormal glucose metabolism (69 male patients and 28 female patients. A controlled study was performed for the clinical data of ALC and HBC patients with abnormal glucose metabolism, to investigate the association of patients′ clinical manifestations with the indices for laboratory examination, insulin resistance index, incidence rate of abnormal glucose metabolism, and Child-Pugh class. The t-test was applied for comparison of continuous data between groups, the chi-square test was applied for comparison of categorical data between groups, and the Spearman rank correlation was applied for correlation analysis. ResultsCompared with HBC patients, ALC patients had significantly higher incidence rates of abnormal glucose metabolism (730% vs 32.4%, hepatogenous diabetes (35.1% vs 14.6%, fasting hypoglycemia (27.0% vs 10.3%, and impaired glucose tolerance (31.1% vs 14.1% (χ2=4.371, 3.274, 4.784, and 1.633, all P＜0.05. The Spearman correlation analysis showed that in ALC and HBC patients, the incidence rate of abnormal glucose metabolism was positively correlated with Child-Pugh class (rs=0.41, P＜005. Compared with the HBC patients with abnormal glucose metabolism, the ALC patients with abnormal glucose metabolism had a significantly higher incidence rate of Child-Pugh class A (χ2=7.520, P=0.001, and a significantly lower incidence rate of Child-Pugh class C (χ2=6.542, P=0.003. There were significant differences in the incidence rates of dim complexion, telangiectasia of the

Usefulness of granular BCAA after hepatectomy for liver cancer complicated with liver cirrhosis.

Science.gov (United States)

Togo, Shinji; Tanaka, Kuniya; Morioka, Daisuke; Sugita, Mitsutaka; Ueda, Michio; Miura, Yasuhiko; Kubota, Toru; Nagano, Yasuhiko; Matsuo, Kenichi; Endo, Itaru; Sekido, Hitoshi; Shimada, Hiroshi

2005-04-01

Nutritional disturbances such as ascites and hypoalbuminemia frequently arise after hepatectomy for liver cancer with liver cirrhosis. We examined the possibility of maintaining a favorable state of nutrition by outpatient administration of branched-chain amino acid (BCAA) granules. Forty-three patients who had gross liver cirrhosis complicated by liver cancer and underwent surgery up to May 2002 were given BCAA granules (n = 21, BCAA group) or no granules (n = 22, control group). 1) Background details such as age, sex, surgical technique, blood loss, and duration of surgery showed no significant differences. 2) Among objective findings, improvement of ascites and edema tended to occur sooner in the BCAA group, but without a significant difference. 3) Although serum albumin recovered its preoperative value 9 mo after surgery in the control group, only 6 mo was required for recovery in the BCAA group. Total protein showed similar changes, but neither group showed any difference in changes of aspartate aminotransferase, alanine transferase, or platelets. 4) One year postoperatively, the change from the preoperative indocyanine green retention rate at 15 min after intravenous administration tended to be worse in the control group, but not significantly so. 5) In the BCAA group, hyaluronic acid and type IV collagen 7S improved significantly sooner than in the control group. BCAA supplementation after hepatectomy promotes rapid improvement in protein metabolism and inhibits progression to liver cirrhosis. Administration of BCAA after hepatectomy is considered beneficial to a patient's nutritional state.

The role of the autonomic nervous liver innervation in the control of energy metabolism

NARCIS (Netherlands)

Yi, Chun-Xia; la Fleur, Susanne E.; Fliers, Eric; Kalsbeek, Andries

2010-01-01

Despite a longstanding research interest ever since the early work by Claude Bernard, the functional significance of autonomic liver innervation, either sympathetic or parasympathetic, is still ill defined. This scarcity of information not only holds for the brain control of hepatic metabolism, but

System-level perturbations of cell metabolism using CRISPR/Cas9

DEFF Research Database (Denmark)

Jakociunas, Tadas; Jensen, Michael Krogh; Keasling, Jay

2017-01-01

CRISPR/Cas9 (clustered regularly interspaced palindromic repeats and the associated protein Cas9) techniques have made genome engineering and transcriptional reprogramming studies more advanced and cost-effective. For metabolic engineering purposes, the CRISPR-based tools have been applied...... previously possible. In this mini-review we highlight recent studies adopting CRISPR/Cas9 for systems-level perturbations and model-guided metabolic engineering....

Abdominal ultrasonography in inheredited diseases of carbohydrate metabolism

International Nuclear Information System (INIS)

Pozzato, Carlo; Curti, Alessandra; Cornalba, Gianpaolo; Radaelli, Giovanni; Fiori, Laura; Rossi, Samantha; Riva, Enrica

2005-01-01

Purpose: To determine the usefulness of abdominal sonography in inherited diseases of carbohydrate metabolism. Materials and methods: Thirty patients (age range, 4 months to 27 years) with glycogen storage diseases, galactosemia, disorders of fructose metabolism were studied with sonography. Echogenicity of the liver, sonographic dimensions of liver, kidneys and spleen were evaluated. Plasma blood parameters (ALT, AST, total cholesterol, triglycerides) were determined. Results: Liver was enlarged in 21/22 patients (95.4%) with glycogen storage diseases, in both subjects with disorders of fructose metabolism, and in 2/6 patients (33.3%) with galactosemia. Hepatic echogenicity was increased in 20/22 patients (90.9%) with glycogen storage diseases, and in the subject with hereditary fructose intolerance. Patients with galactosemia did not show increased liver echogenicity. Both kidney were enlarged in 8/17 patients (47.0%) with glycogen storage disease type I. Subjects with increased hepatic echogenicity exhibited higher plasma concentrations of any blood parameter than the others with normal echogenicity (p [it

Liver and muscle protein metabolism in cachexia

NARCIS (Netherlands)

Peters, J.A.C.

2009-01-01

Up to 50% of cancer patients suffer from progressive weight loss (cachexia). Cachexia is induced by proinflammatory mediators (cytokines), induced by the tumor’s presence. These cytokines induce so-called acute phase protein synthesis by the liver, followed by skeletal muscle protein breakdown.

羟基多溴联苯醚(3'-OH-BDE-7)的大鼠体外肝代谢研究%IN VITRO METABOLISM STUDY OF 3＇-OH-2,4-diBDE-7 IN RAT LIVER S9 FRACTION

Institute of Scientific and Technical Information of China (English)

赖永权; 陈学国; 蔡宗苇

2011-01-01

本文利用液相色谱-质谱联用技术,建立了羟基多溴联苯醚3'-OH-BDE-7在S.D.大鼠肝匀浆中的体外代谢研究方法.实验结果表明,3'-OH-BDE-7的主要代谢产物为2,4-二溴苯酚和二羟基多溴联苯醚(diOHPBDEs),并且其在温孵30min,时代谢转化率为90%.3'-OH-BDE-7的代谢研究为其它羟基多溴联苯醚的相应研究提供了信息,其代谢行为也对更好地理解PBDEs和OH-PBDEs的毒理和动力学具有一定意义.%Polybrominated diphenyl ethers (PBDEs) are an important class of brominated flame retardants that have been widely used in industrial and consumer products. PBDEs have become worldwide environmental pollutants because of the bioaccumulation, long-distance transportation and potential biological toxicities.Hydroxylated polybrominated diphenyl ethers (OH-PBDEs) are a relatively new group of phenolic compounds that have attracted particular interest due to their endocrine disrupting potency. OH-PBDEs are similar to PBDEs in chemical structure, but were reported to show stronger biological effects. In this study, we investigated in vitro metabolic behaviors of selected 3＇-OH-BDE-7 in rat liver S9 fraction. The obtained results indicated that 2,4-dibromophenol and diOH-PBDEs were the major metabolites of OH-PBDEs. It＇s worth noting that the hydroquinone like metabolites might pose a potential health risk to human and wild animals.

Functional proteomic analysis of corticosteroid pharmacodynamics in rat liver: Relationship to hepatic stress, signaling, energy regulation, and drug metabolism.

Science.gov (United States)

Ayyar, Vivaswath S; Almon, Richard R; DuBois, Debra C; Sukumaran, Siddharth; Qu, Jun; Jusko, William J

2017-05-08

Corticosteroids (CS) are anti-inflammatory agents that cause extensive pharmacogenomic and proteomic changes in multiple tissues. An understanding of the proteome-wide effects of CS in liver and its relationships to altered hepatic and systemic physiology remains incomplete. Here, we report the application of a functional pharmacoproteomic approach to gain integrated insight into the complex nature of CS responses in liver in vivo. An in-depth functional analysis was performed using rich pharmacodynamic (temporal-based) proteomic data measured over 66h in rat liver following a single dose of methylprednisolone (MPL). Data mining identified 451 differentially regulated proteins. These proteins were analyzed on the basis of temporal regulation, cellular localization, and literature-mined functional information. Of the 451 proteins, 378 were clustered into six functional groups based on major clinically-relevant effects of CS in liver. MPL-responsive proteins were highly localized in the mitochondria (20%) and cytosol (24%). Interestingly, several proteins were related to hepatic stress and signaling processes, which appear to be involved in secondary signaling cascades and in protecting the liver from CS-induced oxidative damage. Consistent with known adverse metabolic effects of CS, several rate-controlling enzymes involved in amino acid metabolism, gluconeogenesis, and fatty-acid metabolism were altered by MPL. In addition, proteins involved in the metabolism of endogenous compounds, xenobiotics, and therapeutic drugs including cytochrome P450 and Phase-II enzymes were differentially regulated. Proteins related to the inflammatory acute-phase response were up-regulated in response to MPL. Functionally-similar proteins showed large diversity in their temporal profiles, indicating complex mechanisms of regulation by CS. Clinical use of corticosteroid (CS) therapy is frequent and chronic. However, current knowledge on the proteome-level effects of CS in liver and

Metabolic changes associated with the long winter fast dominate the liver proteome in 13-lined ground squirrels

Science.gov (United States)

Hindle, Allyson G.; Grabek, Katharine R.; Epperson, L. Elaine; Karimpour-Fard, Anis

2014-01-01

Small-bodied hibernators partition the year between active homeothermy and hibernating heterothermy accompanied by fasting. To define molecular events underlying hibernation that are both dependent and independent of fasting, we analyzed the liver proteome among two active and four hibernation states in 13-lined ground squirrels. We also examined fall animals transitioning between fed homeothermy and fasting heterothermy. Significantly enriched pathways differing between activity and hibernation were biased toward metabolic enzymes, concordant with the fuel shifts accompanying fasting physiology. Although metabolic reprogramming to support fasting dominated these data, arousing (rewarming) animals had the most distinct proteome among the hibernation states. Instead of a dominant metabolic enzyme signature, torpor-arousal cycles featured differences in plasma proteins and intracellular membrane traffic and its regulation. Phosphorylated NSFL1C, a membrane regulator, exhibited this torpor-arousal cycle pattern; its role in autophagosome formation may promote utilization of local substrates upon metabolic reactivation in arousal. Fall animals transitioning to hibernation lagged in their proteomic adjustment, indicating that the liver is more responsive than preparatory to the metabolic reprogramming of hibernation. Specifically, torpor use had little impact on the fall liver proteome, consistent with a dominant role of nutritional status. In contrast to our prediction of reprogramming the transition between activity and hibernation by gene expression and then within-hibernation transitions by posttranslational modification (PTM), we found extremely limited evidence of reversible PTMs within torpor-arousal cycles. Rather, acetylation contributed to seasonal differences, being highest in winter (specifically in torpor), consistent with fasting physiology and decreased abundance of the mitochondrial deacetylase, SIRT3. PMID:24642758

Partition and metabolic fate of dietary glycerol in muscles and liver of juvenile tilapia.

Science.gov (United States)

da Costa, Diego Vicente; Dias, Jorge; Colen, Rita; Rosa, Priscila Vieira; Engrola, Sofia

2017-04-01

This study investigated the effect of dietary glycerol on the metabolism of juvenile tilapia (Oreochromis mossambicus) and to determine its metabolic fate. The experimental diets contained 0% (Group CON), 5% (Group G5) and 15% glycerol (Group G15) and were fed for 40 d to apparent satiation, three times a day. For the metabolism trials, six fish from each treatment were randomly chosen and tube-fed with five pellets labelled with 14 C-glycerol [ 14 C(U)] in order to evaluate the absorption, catabolism, retention and partition of glycerol in muscle and liver. Group G5 presented the highest 14 C-glycerol retention and the lowest catabolism, with no significant differences between Groups CON and G15. In Group CON, the highest percentage of 14 C was incorporated in muscle lipids; with no significant differences between Groups G5 and G15. Furthermore, no treatment effects were found for hepatic 14 C-lipid and for 14 C in hepatic and muscle non-lipid extract. In the non-lipid and non-protein fraction, the highest radioactivity was measured in livers of Group G5, however no significant differences were found for this fraction between Groups CON and G15 in liver and for all treatments in muscle. The results of the present study can have practical implications in diet formulations for tilapia and for other aquaculture species with similar feeding pattern since juvenile tilapia are able to metabolise dietary glycerol into lipids, protein and/or carbohydrates and to use it as energy source.

Aerobic interval exercise improves parameters of nonalcoholic fatty liver disease (NAFLD) and other alterations of metabolic syndrome in obese Zucker rats.

Science.gov (United States)

Kapravelou, Garyfallia; Martínez, Rosario; Andrade, Ana M; Nebot, Elena; Camiletti-Moirón, Daniel; Aparicio, Virginia A; Lopez-Jurado, Maria; Aranda, Pilar; Arrebola, Francisco; Fernandez-Segura, Eduardo; Bermano, Giovanna; Goua, Marie; Galisteo, Milagros; Porres, Jesus M

2015-12-01

Metabolic syndrome (MS) is a group of metabolic alterations that increase the susceptibility to cardiovascular disease and type 2 diabetes. Nonalcoholic fatty liver disease has been described as the liver manifestation of MS. We aimed to test the beneficial effects of an aerobic interval training (AIT) protocol on different biochemical, microscopic, and functional liver alterations related to the MS in the experimental model of obese Zucker rat. Two groups of lean and obese animals (6 weeks old) followed a protocol of AIT (4 min at 65%-80% of maximal oxygen uptake, followed by 3 min at 50%-65% of maximal oxygen uptake for 45-60 min, 5 days/week, 8 weeks of experimental period), whereas 2 control groups remained sedentary. Obese rats had higher food intake and body weight (P metabolism and increased the liver protein expression of PPARγ, as well as the gene expression of glutathione peroxidase 4 (P < 0.001). The training protocol also showed significant effects on the activity of hepatic antioxidant enzymes, although this action was greatly influenced by rat phenotype. The present data suggest that AIT protocol is a feasible strategy to improve some of the plasma and liver alterations featured by the MS.

Metabolically induced liver inflammation leads to NASH and differs from LPS- or IL-1β-induced chronic inflammation.

Science.gov (United States)

Liang, Wen; Lindeman, Jan H; Menke, Aswin L; Koonen, Debby P; Morrison, Martine; Havekes, Louis M; van den Hoek, Anita M; Kleemann, Robert

2014-05-01

The nature of the chronic inflammatory component that drives the development of non-alcoholic steatohepatitis (NASH) is unclear and possible inflammatory triggers have not been investigated systematically. We examined the effect of non-metabolic triggers (lipopolysaccharide (LPS), interleukin-1β (IL-1β), administered by slow-release minipumps) and metabolic dietary triggers (carbohydrate, cholesterol) of inflammation on the progression of bland liver steatosis (BS) to NASH. Transgenic APOE3*Leiden.huCETP (APOE3L.CETP) mice fed a high-fat diet (HFD) developed BS after 10 weeks. Then, inflammatory triggers were superimposed or not (control) for six more weeks. Mouse livers were analyzed with particular emphasis on hallmarks of inflammation which were defined in human liver biopsies with and without NASH. Livers of HFD-treated control mice remained steatotic and did not progress to NASH. All four inflammatory triggers activated hepatic nuclear factor-κB (NF-κB) significantly and comparably (≥5-fold). However, HFD+LPS or HFD+IL-1β did not induce a NASH-like phenotype and caused intrahepatic accumulation of almost exclusively mononuclear cells. By contrast, mice treated with metabolic triggers developed NASH, characterized by enhanced steatosis, hepatocellular hypertrophy, and formation of mixed-type inflammatory foci containing myeloperoxidase-positive granulocytes (neutrophils) as well as mononuclear cells, essentially as observed in human NASH. Specific for the metabolic inducers was an activation of the proinflammatory transcription factor activator protein-1 (AP-1), neutrophil infiltration, and induction of risk factors associated with human NASH, that is, dyslipidemia (by cholesterol) and insulin resistance (by carbohydrate). In conclusion, HFD feeding followed by NF-κB activation per se (LPS, IL-1β) does not promote the transition from BS to NASH. HFD feeding followed by metabolically evoked inflammation induces additional inflammatory components

Metabolic Characterization of Peripheral Host Responses to Drainage-Resistant Klebsiella pneumoniae Liver Abscesses by Serum 1H-NMR Spectroscopy

Directory of Open Access Journals (Sweden)

Zhihui Chang

2018-06-01

Full Text Available Purpose: To explore the metabolic characterization of host responses to drainage-resistant Klebsiella pneumoniae liver abscesses (DRKPLAs with serum 1H-nuclear magnetic resonance (NMR spectroscopy.Materials and Methods: The hospital records of all patients with a diagnosis of a liver abscess between June 2015 and December 2016 were retrieved from an electronic hospital database. Eighty-six patients with Klebsiella pneumoniae (K. pneumoniae liver abscesses who underwent percutaneous drainage were identified. Twenty patients with confirmed DRKPLAs were studied. Moreover, we identified 20 consecutive patients with drainage-sensitive Klebsiella pneumoniae liver abscesses (DSKPLAs as controls. Serum samples from the two groups were analyzed with 1H NMR spectroscopy. Partial least squares discriminant analysis (PLS-DA was used to perform 1H NMR metabolic profiling. Metabolites were identified using the Human Metabolome Database, and pathway analysis was performed with MetaboAnalyst 3.0.Results: The PLS-DA test was able to discriminate between the two groups. Five key metabolites that contributed to their discrimination were identified. Glucose, lactate, and 3-hydroxybutyrate were found to be upregulated in DRKPLAs, whereas glutamine and alanine were downregulated compared with the DSKPLAs. Pathway analysis indicated that amino acid metabolisms were significantly different between the DRKPLAs and the DSKPLAs. The D-glutamine and D-glutamate metabolisms exhibited the greatest influences.Conclusions: The five key metabolites identified in our study may be potential targets for guiding novel therapeutics of DRKPLAs and are worthy of additional investigation.

Reduction of liver fructokinase expression and improved hepatic inflammation and metabolism in liquid fructose-fed rats after atorvastatin treatment

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Vila, Laia; Rebollo, Alba; Adalsteisson, Gunnar S [Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, School of Pharmacy, University of Barcelona, Barcelona (Spain); Alegret, Marta; Merlos, Manuel; Roglans, Nuria [Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, School of Pharmacy, University of Barcelona, Barcelona (Spain); IBUB - Institute of Biomedicine, University of Barcelona, Barcelona (Spain); CIBERobn, [Center for Biomedical Investigation Network in Obesity and Nutrition Physiopathology; Spain; Laguna, Juan C., E-mail: jclagunae@ub.edu [Pharmacology Unit, Department of Pharmacology and Therapeutic Chemistry, School of Pharmacy, University of Barcelona, Barcelona (Spain); IBUB -Institute of Biomedicine, University of Barcelona, Barcelona (Spain); CIBERobn, [Center for Biomedical Investigation Network in Obesity and Nutrition Physiopathology; Spain

2011-02-15

Consumption of beverages that contain fructose favors the increasing prevalence of metabolic syndrome alterations in humans, including non-alcoholic fatty liver disease (NAFLD). Although the only effective treatment for NAFLD is caloric restriction and weight loss, existing data show that atorvastatin, a hydroxymethyl-glutaryl-CoA reductase inhibitor, can be used safely in patients with NAFLD and improves hepatic histology. To gain further insight into the molecular mechanisms of atorvastatin's therapeutic effect on NAFLD, we used an experimental model that mimics human consumption of fructose-sweetened beverages. Control, fructose (10% w/v solution) and fructose + atorvastatin (30 mg/kg/day) Sprague-Dawley rats were sacrificed after 14 days. Plasma and liver tissue samples were obtained to determine plasma analytes, liver histology, and the expression of liver proteins that are related to fatty acid synthesis and catabolism, and inflammatory processes. Fructose supplementation induced hypertriglyceridemia and hyperleptinemia, hepatic steatosis and necroinflammation, increased the expression of genes related to fatty acid synthesis and decreased fatty acid {beta}-oxidation activity. Atorvastatin treatment completely abolished histological signs of necroinflammation, reducing the hepatic expression of metallothionein-1 and nuclear factor kappa B binding. Furthermore, atorvastatin reduced plasma (x 0.74) and liver triglyceride (x 0.62) concentrations, decreased the liver expression of carbohydrate response element binding protein transcription factor (x0.45) and its target genes, and increased the hepatic activity of the fatty acid {beta}-oxidation system (x 1.15). These effects may be related to the fact that atorvastatin decreased the expression of fructokinase (x 0.6) in livers of fructose-supplemented rats, reducing the metabolic burden on the liver that is imposed by continuous fructose ingestion. - Graphical Abstract: Display Omitted Research Highlights

Reduction of liver fructokinase expression and improved hepatic inflammation and metabolism in liquid fructose-fed rats after atorvastatin treatment

International Nuclear Information System (INIS)

Vila, Laia; Rebollo, Alba; Adalsteisson, Gunnar S.; Alegret, Marta; Merlos, Manuel; Roglans, Nuria; Laguna, Juan C.

2011-01-01

Consumption of beverages that contain fructose favors the increasing prevalence of metabolic syndrome alterations in humans, including non-alcoholic fatty liver disease (NAFLD). Although the only effective treatment for NAFLD is caloric restriction and weight loss, existing data show that atorvastatin, a hydroxymethyl-glutaryl-CoA reductase inhibitor, can be used safely in patients with NAFLD and improves hepatic histology. To gain further insight into the molecular mechanisms of atorvastatin's therapeutic effect on NAFLD, we used an experimental model that mimics human consumption of fructose-sweetened beverages. Control, fructose (10% w/v solution) and fructose + atorvastatin (30 mg/kg/day) Sprague-Dawley rats were sacrificed after 14 days. Plasma and liver tissue samples were obtained to determine plasma analytes, liver histology, and the expression of liver proteins that are related to fatty acid synthesis and catabolism, and inflammatory processes. Fructose supplementation induced hypertriglyceridemia and hyperleptinemia, hepatic steatosis and necroinflammation, increased the expression of genes related to fatty acid synthesis and decreased fatty acid β-oxidation activity. Atorvastatin treatment completely abolished histological signs of necroinflammation, reducing the hepatic expression of metallothionein-1 and nuclear factor kappa B binding. Furthermore, atorvastatin reduced plasma (x 0.74) and liver triglyceride (x 0.62) concentrations, decreased the liver expression of carbohydrate response element binding protein transcription factor (x0.45) and its target genes, and increased the hepatic activity of the fatty acid β-oxidation system (x 1.15). These effects may be related to the fact that atorvastatin decreased the expression of fructokinase (x 0.6) in livers of fructose-supplemented rats, reducing the metabolic burden on the liver that is imposed by continuous fructose ingestion. - Graphical Abstract: Display Omitted Research Highlights: �

BIOCHEMICAL MARKERS OF BONE RESORPTION AND HORMONAL REGULATION OF BONE METABOLISM FOLLOWING LIVER TRANSPLANTATION

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V. P. Buzulina

2013-01-01

Full Text Available Aim. Comparative evaluation of two biochemical markers of bone resorption and hormonal regulation of bone metabolism in liver recipients. Methods and results. Bоne densitometry of L2–L4 and neck of femur, serum level of some hormones (PTH, vitamin D3, estradiol, testosterone regulating osteoclastogenesis as well as com- parative analyses of two bone resorption markers β-crosslaps and tartrate-resistant acid phosphatase type 5b (TRAP-5b were fulfilled in patients after orthotopic liver transplantation (OLT. In 1 month after OLT bone density reduction of L2–L4 and neck of femur; decrease of vitamin D3, estradiol in women, testosterone in men and increase levels of bone resorption markers were observed. In 1 and 2 years after OLT the rise of bone density, increased levels of PTH, estradiol, testosterone and decreased β-crosslaps levels were revealed, while vitamin D3 and TRAP-5b levels remained stable. Conclusion. TRAP-5b was found to be a more speciffic marker of bone resorption, independent from collagen metabolism in liver. Osteoporosis defined in long-term period after OLT was associated with higher TRAP-5b and revialed in women with low estradiol level. 

Ob/ob mouse livers show decreased oxidative phosphorylation efficiencies and anaerobic capacities after cold ischemia.

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Michael J J Chu

Full Text Available BACKGROUND: Hepatic steatosis is a major risk factor for graft failure in liver transplantation. Hepatic steatosis shows a greater negative influence on graft function following prolonged cold ischaemia. As the impact of steatosis on hepatocyte metabolism during extended cold ischaemia is not well-described, we compared markers of metabolic capacity and mitochondrial function in steatotic and lean livers following clinically relevant durations of cold preservation. METHODS: Livers from 10-week old leptin-deficient obese (ob/ob, n = 9 and lean C57 mice (n = 9 were preserved in ice-cold University of Wisconsin solution. Liver mitochondrial function was then assessed using high resolution respirometry after 1.5, 3, 5, 8, 12, 16 and 24 hours of storage. Metabolic marker enzymes for anaerobiosis and mitochondrial mass were also measured in conjunction with non-bicarbonate tissue pH buffering capacity. RESULTS: Ob/ob and lean mice livers showed severe (>60% macrovesicular and mild (<30% microvesicular steatosis on Oil Red O staining, respectively. Ob/ob livers had lower baseline enzymatic complex I activity but similar adenosine triphosphate (ATP levels compared to lean livers. During cold storage, the respiratory control ratio and complex I-fueled phosphorylation deteriorated approximately twice as fast in ob/ob livers compared to lean livers. Ob/ob livers also demonstrated decreased ATP production capacities at all time-points analyzed compared to lean livers. Ob/ob liver baseline lactate dehydrogenase activities and intrinsic non-bicarbonate buffering capacities were depressed by 60% and 40%, respectively compared to lean livers. CONCLUSIONS: Steatotic livers have impaired baseline aerobic and anaerobic capacities compared to lean livers, and mitochondrial function indices decrease particularly from after 5 hours of cold preservation. These data provide a mechanistic basis for the clinical recommendation of shorter cold storage durations in

Metabolic profiles are principally different between cancers of the liver, pancreas and breast.

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Budhu, Anuradha; Terunuma, Atsushi; Zhang, Geng; Hussain, S Perwez; Ambs, Stefan; Wang, Xin Wei

2014-01-01

Molecular profiling of primary tumors may facilitate the classification of patients with cancer into more homogenous biological groups to aid clinical management. Metabolomic profiling has been shown to be a powerful tool in characterizing the biological mechanisms underlying a disease but has not been evaluated for its ability to classify cancers by their tissue of origin. Thus, we assessed metabolomic profiling as a novel tool for multiclass cancer characterization. Global metabolic profiling was employed to identify metabolites in paired tumor and non-tumor liver (n=60), breast (n=130) and pancreatic (n=76) tissue specimens. Unsupervised principal component analysis showed that metabolites are principally unique to each tissue and cancer type. Such a difference can also be observed even among early stage cancers, suggesting a significant and unique alteration of global metabolic pathways associated with each cancer type. Our global high-throughput metabolomic profiling study shows that specific biochemical alterations distinguish liver, pancreatic and breast cancer and could be applied as cancer classification tools to differentiate tumors based on tissue of origin.

Phenylalanine metabolism in isolated rat liver cells. Effects of glucagon and diabetes.

OpenAIRE

Carr, F P; Pogson, C I

1981-01-01

1. Methods are described for monitoring the metabolic flux through phenylalanine hydroxylase, the tyrosine catabolic pathway and phenylalanine: pyruvate transaminase in isolated liver cell incubations. 2. The relationship between hydroxylase flux and phenylalanine concentration is sigmoidal. 3. Glucagon increases hydroxylase activity at low, near-physiological, substrate concentrations only. The hormone does not affect the rate of formation of phenylpyruvate. 4. Experimental diabetes (for 10 ...

Ananas comosus L. Leaf Phenols and p-Coumaric Acid Regulate Liver Fat Metabolism by Upregulating CPT-1 Expression

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Weidong Xie

2014-01-01

Full Text Available In this study, we aimed to investigate the effect and action mechanisms of pineapple leaf phenols (PLPs on liver fat metabolism in high-fat diet-fed mice. Results show that PLP significantly reduced abdominal fat and liver lipid accumulation in high-fat diet-fed mice. The effects of PLP were comparable with those of FB. Furthermore, at the protein level, PLP upregulated the expression of carnitine palmitoyltransferase 1 (CPT-1, whereas FB had no effects on CPT-1 compared with the HFD controls. Regarding mRNA expression, PLP mainly promoted the expression of CPT-1, PGC1a, UCP-1, and AMPK in the mitochondria, whereas FB mostly enhanced the expression of Ech1, Acox1, Acaa1, and Ehhadh in peroxisomes. PLP seemed to enhance fat metabolism in the mitochondria, whereas FB mainly exerted the effect in peroxisomes. In addition, p-coumaric acid (CA, one of the main components from PLP, significantly inhibited fat accumulation in oleic acid-induced HepG2 cells. CA also significantly upregulated CPT-1 mRNA and protein expressions in HepG2 cells. We, firstly, found that PLP enhanced liver fat metabolism by upregulating CPT-1 expression in the mitochondria and might be promising in treatment of fatty liver diseases as alternative natural products. CA may be one of the active components of PLP.

Effects of Perfluorooctanoic Acid on Metabolic Profiles in Brain and Liver of Mouse Revealed by a High-throughput Targeted Metabolomics Approach

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Yu, Nanyang; Wei, Si; Li, Meiying; Yang, Jingping; Li, Kan; Jin, Ling; Xie, Yuwei; Giesy, John P.; Zhang, Xiaowei; Yu, Hongxia

2016-04-01

Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, can result in hepatotoxicity and neurobehavioral effects in animals. The metabolome, which serves as a connection among transcriptome, proteome and toxic effects, provides pathway-based insights into effects of PFOA. Since understanding of changes in the metabolic profile during hepatotoxicity and neurotoxicity were still incomplete, a high-throughput targeted metabolomics approach (278 metabolites) was used to investigate effects of exposure to PFOA for 28 d on brain and liver of male Balb/c mice. Results of multivariate statistical analysis indicated that PFOA caused alterations in metabolic pathways in exposed individuals. Pathway analysis suggested that PFOA affected metabolism of amino acids, lipids, carbohydrates and energetics. Ten and 18 metabolites were identified as potential unique biomarkers of exposure to PFOA in brain and liver, respectively. In brain, PFOA affected concentrations of neurotransmitters, including serotonin, dopamine, norepinephrine, and glutamate in brain, which provides novel insights into mechanisms of PFOA-induced neurobehavioral effects. In liver, profiles of lipids revealed involvement of β-oxidation and biosynthesis of saturated and unsaturated fatty acids in PFOA-induced hepatotoxicity, while alterations in metabolism of arachidonic acid suggesting potential of PFOA to cause inflammation response in liver. These results provide insight into the mechanism and biomarkers for PFOA-induced effects.

In vivo 19F-MRS observation of 5-FU metabolism in fatty liver induced by choline-deficient diet

International Nuclear Information System (INIS)

Otsuka, Hideki; Harada, Masafumi; Nishitani, Hiromu; Koga, Keiko.

1996-01-01

Using 19 F-MRS, 5-FU metabolism was investigated in rat fatty liver. Fatty liver was induced by choline-deficient diet (CD diet). This study showed differences in 5-FU metabolism between normal and fatty liver. After laparotomy, a surface coil was placed directly on the liver surface. Spectra were continuously obtained after injection of 5-FU 100 mg/kg body weight via a catheter inserted into femoral vein. We made MRI and 1 H-MRS study to examine the lipid accumulation. Histological study was also performed using HE (hematoxylin-eosin) and oil red stain. The livers of rats fed a CD diet showed very high intensity on T 1 -WI. 1 H-MRS was very useful in deteminating the fat content because the fat ratio demonstrated by 1 H-MRS is well correlated to histological findings. In 19 F-MRS, we recognized the following four peaks: 5-FU, FBAL, Fnct (fluoronucleotide) and FUPA. The decrease of 5-FU was not very apparent, but compared to the normal liver, the formation of Fnct increased and the formation of FBAL was suppressed in fatty liver. The rats fed a CD diet for four weeks showed a higher Fnct peak and lower FBAL peak compared with the results of rats fed a CD diet for two weeks. In a CD diet group, liver cell degeneration and necrotic changes were observed histologically. It is reported that cell degeneration is followed by cell proliferation in fatty liver induced by a choline deficient diet, and the high Fnct peak found in our study may reflect this phenomenon. The high Fnct peak on 19 F-MRS may correspond to recovering reaction from liver injury like fatty liver. (author)

Metabolic effects of the iodothyronine functional analogue TRC150094 on the liver and skeletal muscle of high-fat diet fed overweight rats: an integrated proteomic study.

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Silvestri, Elena; Glinni, Daniela; Cioffi, Federica; Moreno, Maria; Lombardi, Assunta; de Lange, Pieter; Senese, Rosalba; Ceccarelli, Michele; Salzano, Anna Maria; Scaloni, Andrea; Lanni, Antonia; Goglia, Fernando

2012-07-06

A novel functional iodothyronine analogue, TRC150094, which has a much lower potency toward thyroid hormone receptor (α1/β1) activation than triiodothyronine, has been shown to be effective at reducing adiposity in rats simultaneously receiving a high-fat diet (HFD). Here, by combining metabolic, functional and proteomic analysis, we studied how the hepatic and skeletal muscle phenotypes might respond to TRC150094 treatment in HFD-fed overweight rats. Drug treatment increased both the liver and skeletal muscle mitochondrial oxidative capacities without altering mitochondrial efficiency. Coherently, in terms of individual respiratory in-gel activity, blue-native analysis revealed an increased activity of complex V in the liver and of complexes II and V in tibialis muscle in TCR150094-treated animals. Subsequently, the identification of differentially expressed proteins and the analysis of their interrelations gave an integrated view of the phenotypic/metabolic adaptations occurring in the liver and muscle proteomes during drug treatment. TRC150094 significantly altered the expression of several proteins involved in key liver metabolic pathways, including amino acid and nitrogen metabolism, and fructose and mannose metabolism. The canonical pathways most strongly influenced by TRC150094 in tibialis muscle included glycolysis and gluconeogenesis, amino acid, fructose and mannose metabolism, and cell signaling. The phenotypic/metabolic influence of TRC150094 on the liver and skeletal muscle of HFD-fed overweight rats suggests the potential clinical application of this iodothyronine analogue in ameliorating metabolic risk parameters altered by diet regimens.

Characterisation of the cytochrome P450 enzymes involved in the in vitro metabolism of granisetron.

OpenAIRE

Bloomer, J C; Baldwin, S J; Smith, G J; Ayrton, A D; Clarke, S E; Chenery, R J

1994-01-01

1. The metabolism of granisetron was investigated in human liver microsomes to identify the specific forms of cytochrome P450 responsible. 2. 7-hydroxy and 9'-desmethyl granisetron were identified as the major products of metabolism following incubation of granisetron with human liver microsomes. At low, clinically relevant, concentrations of granisetron the 7-hydroxy metabolite predominated. Rates of granisetron 7-hydroxylation varied over 100-fold in the human livers investigated. 3. Enzyme...

Metabolic changes associated with the long winter fast dominate the liver proteome in 13-lined ground squirrels.

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Hindle, Allyson G; Grabek, Katharine R; Epperson, L Elaine; Karimpour-Fard, Anis; Martin, Sandra L

2014-05-15

Small-bodied hibernators partition the year between active homeothermy and hibernating heterothermy accompanied by fasting. To define molecular events underlying hibernation that are both dependent and independent of fasting, we analyzed the liver proteome among two active and four hibernation states in 13-lined ground squirrels. We also examined fall animals transitioning between fed homeothermy and fasting heterothermy. Significantly enriched pathways differing between activity and hibernation were biased toward metabolic enzymes, concordant with the fuel shifts accompanying fasting physiology. Although metabolic reprogramming to support fasting dominated these data, arousing (rewarming) animals had the most distinct proteome among the hibernation states. Instead of a dominant metabolic enzyme signature, torpor-arousal cycles featured differences in plasma proteins and intracellular membrane traffic and its regulation. Phosphorylated NSFL1C, a membrane regulator, exhibited this torpor-arousal cycle pattern; its role in autophagosome formation may promote utilization of local substrates upon metabolic reactivation in arousal. Fall animals transitioning to hibernation lagged in their proteomic adjustment, indicating that the liver is more responsive than preparatory to the metabolic reprogramming of hibernation. Specifically, torpor use had little impact on the fall liver proteome, consistent with a dominant role of nutritional status. In contrast to our prediction of reprogramming the transition between activity and hibernation by gene expression and then within-hibernation transitions by posttranslational modification (PTM), we found extremely limited evidence of reversible PTMs within torpor-arousal cycles. Rather, acetylation contributed to seasonal differences, being highest in winter (specifically in torpor), consistent with fasting physiology and decreased abundance of the mitochondrial deacetylase, SIRT3. Copyright © 2014 the American Physiological Society.

Metabolism of a sea lamprey pesticide by fish liver enzymes part A: identification and synthesis of TFM metabolites.

Science.gov (United States)

Bussy, Ugo; Chung-Davidson, Yu-Wen; Buchinger, Tyler; Li, Ke; Smith, Scott A; Jones, A Daniel; Li, Weiming

2018-02-01

The sea lamprey (Petromyzon marinus) is a destructive invasive species in the Great Lakes that contributed to the collapse of native fish populations in the mid-1900s. 3-Trifluoromethyl-4-nitrophenol (TFM) is a selective pesticide that has been applied to sea lamprey infested tributaries of the Great Lakes to kill larvae since the 1960s and has reduced the populations by as much as 90%. However, the metabolism of TFM by sea lamprey and non-target species is not fully illuminated. Elucidation of TFM metabolism is critical for understanding its mode of action and possible environmental impact. Here, we describe the screening, identification, synthesis and structural characterization of TFM metabolites in livers from sea lamprey and three non-target species that differ in their ability to survive TFM exposure. We identified glucuronidation, sulfation, N-acetylation, glutathione conjugation, and aromatic nitro group reduction as potential detoxification mechanisms. Seven metabolites were synthesized for use as markers of TFM metabolism in fish. Quantitative 1 H NMR was used to assay synthesized metabolite stock solutions that were then used as standard material to develop a quantitative LC-MS/MS method for TFM metabolites.

Effect of thiamine deficiency, pyrithiamine and oxythiamine on pyruvate metabolism in rat liver and brain in vivo

International Nuclear Information System (INIS)

Meghal, S.K.; O'Neal, R.M.; Koeppe, R.E.

1977-01-01

Rats were fed either a thiamine-deficient diet or diets containing pyrithiamine or oxythiamine. When symptoms of thiamine deficiency appeared, the animals were injected intraperitoneally with [2- 14 C] pyruvate six to twelve minutes prior to sacrifice. Free glutamic and aspartic acids were isolated from liver and brain and degraded. The results indicate that, in thiamine-deficient or oxythiamine-treated rats, pyruvate metabolism in liver and brain is similar to that in normal animals. In contrast, pyrithinamine drastically decreases the oxidative decarboxylation of pyruvate by rat liver. (auth.)

Dysfunctional Muscle and Liver Glycogen Metabolism in mdx Dystrophic Mice

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Stapleton, David I.; Lau, Xianzhong; Flores, Marcelo; Trieu, Jennifer; Gehrig, Stefan M.; Chee, Annabel; Naim, Timur; Lynch, Gordon S.; Koopman, René

2014-01-01

Background Duchenne muscular dystrophy (DMD) is a severe, genetic muscle wasting disorder characterised by progressive muscle weakness. DMD is caused by mutations in the dystrophin (dmd) gene resulting in very low levels or a complete absence of the dystrophin protein, a key structural element of muscle fibres which is responsible for the proper transmission of force. In the absence of dystrophin, muscle fibres become damaged easily during contraction resulting in their degeneration. DMD patients and mdx mice (an animal model of DMD) exhibit altered metabolic disturbances that cannot be attributed to the loss of dystrophin directly. We tested the hypothesis that glycogen metabolism is defective in mdx dystrophic mice. Results Dystrophic mdx mice had increased skeletal muscle glycogen (79%, (Pglycogen synthesis is initiated by glycogenin, the expression of which was increased by 50% in mdx mice (PGlycogen synthase activity was 12% higher (Pglycogen branching enzyme activity was 70% lower (Pglycogen breakdown, glycogen phosphorylase, had 62% lower activity (Pglycogen debranching enzyme expression was 50% higher (Pglycogen (Pglycogen metabolism in mdx mice identified reduced glycogenin protein expression (46% less; Pglycogen but reduced amounts of liver glycogen. PMID:24626262

Salecan protected against concanavalin A-induced acute liver injury by modulating T cell immune responses and NMR-based metabolic profiles

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Sun, Qi; Xu, Xi, E-mail: xuxi@njust.edu.cn; Yang, Xiao; Weng, Dan; Wang, Junsong; Zhang, Jianfa

2017-02-15

Salecan, a water-soluble extracellular β-glucan produced by Agrobacterium sp. ZX09, has been reported to exhibit a wide range of biological effects. The aims of the present study were to investigate the protective effect of salecan against Concanavalin A (ConA)-induced hepatitis, a well-established animal model of immune-mediated liver injury, and to search for possible mechanisms. C57BL/6 mice were pretreated with salecan followed by ConA injection. Salecan treatment significantly reduced ConA-induced acute liver injury, and suppressed the expression and secretion of inflammatory cytokines including interferon (IFN)-γ, interleukin (IL)-6 and IL-1β in ConA-induced liver injury model. The high expression levels of chemokines and adhesion molecules such as MIP-1α, MIP-1β, ICAM-1, MCP-1 and RANTES in the liver induced by ConA were also down-regulated after salecan treatment. Salecan inhibited the infiltration and activation of inflammatory cells, especially T cells, in the liver induced by ConA. Moreover, salecan reversed the metabolic profiles of ConA-treated mice towards the control group by partly recovering the metabolic perturbations induced by ConA. Our results suggest the preventive and therapeutic potential of salecan in immune-mediated hepatitis. - Highlights: • Salecan treatment significantly reduced ConA-induced liver injury. • Salecan suppressed the expression and secretion of inflammatory cytokines. • Salecan decreased the expression of chemokines and adhesion molecules in liver. • Salecan inhibited the infiltration and activation of T cells induced by ConA. • Salecan partly recovered the metabolic perturbations induced by ConA.

Basil extract inhibits the sulfotransferase mediated formation of DNA adducts of the procarcinogen 1'-hydroxyestragole by rat and human liver S9 homogenates and in HepG2 human hepatoma cells

NARCIS (Netherlands)

Jeurissen, S.M.F.; Punt, A.; Delatour, T.; Rietjens, I.M.C.M.

2008-01-01

The effects of a basil extract on the sulfation and concomitant DNA adduct formation of the proximate carcinogen 1¿-hydroxyestragole were studied using rat and human liver S9 homogenates and the human hepatoma cell line HepG2. Basil was chosen since it contains the procarcinogen estragole that can

Metabolic changes in the pig liver during warm ischemia and reperfusion measured by microdialysis

DEFF Research Database (Denmark)

Kannerup, Anne-Sofie; Funch-Jensen, Peter; Grønbaek, Henning

2008-01-01

AIM: Portal triad clamping can cause ischemia-reperfusion injury. The aim of the study was to monitor metabolic changes by microdialysis before, during, and after warm ischemia in the pigliver. MATERIAL AND METHODS: Eight pigs underwent laparotomy followed by ischemia by Pringle's maneuver. One...... in transaminase levels was observed. CONCLUSIONS: During and after warm ischemia, there were profound metabolic changes in the pigliver observed with an increase in lactate, glucose, glycerol, and the lactate-pyruvate ratio. There were no differences between the four liver lobes, indicating the piglivers...

Pulmonary Ozone Exposure Alters Essential Metabolic Pathways involved in Glucose Homeostasis in the Liver

Science.gov (United States)

Pulmonary Ozone Exposure Alters Essential Metabolic Pathways involved in Glucose Homeostasis in the Liver D.B. Johnson, 1 W.O. Ward, 2 V.L. Bass, 2 M.C.J. Schladweiler, 2A.D. Ledbetter, 2 D. Andrews, and U.P. Kodavanti 2 1 Curriculum in Toxicology, UNC School of Medicine, Cha...

(1)H-MRS measured ectopic fat in liver and muscle is associated with the metabolic syndrome in Danish girls but not in boys with overweight and obesity

DEFF Research Database (Denmark)

Nissen, A; Fonvig, Cilius E; Chabanova, E.

2016-01-01

BACKGROUND: The metabolic syndrome (MetS) is a complication to overweight and obesity, which can be observed already in childhood. Ectopic lipid accumulation in muscle and liver has been shown to associate with the development of insulin resistance and dyslipidemia. Thus, the interaction between...

Multi-omic network-based interrogation of rat liver metabolism following gastric bypass surgery featuring SWATH proteomics.

Science.gov (United States)

Sridharan, Gautham Vivek; D'Alessandro, Matthew; Bale, Shyam Sundhar; Bhagat, Vicky; Gagnon, Hugo; Asara, John M; Uygun, Korkut; Yarmush, Martin L; Saeidi, Nima

2017-09-01

Morbidly obese patients often elect for Roux-en-Y gastric bypass (RYGB), a form of bariatric surgery that triggers a remarkable 30% reduction in excess body weight and reversal of insulin resistance for those who are type II diabetic. A more complete understanding of the underlying molecular mechanisms that drive the complex metabolic reprogramming post-RYGB could lead to innovative non-invasive therapeutics that mimic the beneficial effects of the surgery, namely weight loss, achievement of glycemic control, or reversal of non-alcoholic steatohepatitis (NASH). To facilitate these discoveries, we hereby demonstrate the first multi-omic interrogation of a rodent RYGB model to reveal tissue-specific pathway modules implicated in the control of body weight regulation and energy homeostasis. In this study, we focus on and evaluate liver metabolism three months following RYGB in rats using both SWATH proteomics, a burgeoning label free approach using high resolution mass spectrometry to quantify protein levels in biological samples, as well as MRM metabolomics. The SWATH analysis enabled the quantification of 1378 proteins in liver tissue extracts, of which we report the significant down-regulation of Thrsp and Acot13 in RYGB as putative targets of lipid metabolism for weight loss. Furthermore, we develop a computational graph-based metabolic network module detection algorithm for the discovery of non-canonical pathways, or sub-networks, enriched with significantly elevated or depleted metabolites and proteins in RYGB-treated rat livers. The analysis revealed a network connection between the depleted protein Baat and the depleted metabolite taurine, corroborating the clinical observation that taurine-conjugated bile acid levels are perturbed post-RYGB.

The hepatic stellate cell in sight : targeting antiproliferative drugs to the fibrotic liver

NARCIS (Netherlands)

Greupink, Albert Hendrikus

2006-01-01

Liver fibrosis is characterized by the accumulation of excessive amounts of scar tissue in response to chronic liver injury. Important causes of chronic liver injury are viral hepatitis, metabolic disorders such as Wilson’s disease, autoimmune diseases and chronic exposure to certain chemicals,

Shift work or food intake during the rest phase promotes metabolic disruption and desynchrony of liver genes in male rats.

Science.gov (United States)

Salgado-Delgado, Roberto C; Saderi, Nadia; Basualdo, María del Carmen; Guerrero-Vargas, Natali N; Escobar, Carolina; Buijs, Ruud M

2013-01-01

In the liver, clock genes are proposed to drive metabolic rhythms. These gene rhythms are driven by the suprachiasmatic nucleus (SCN) mainly by food intake and via autonomic and hormonal pathways. Forced activity during the normal rest phase, induces also food intake, thus neglecting the signals of the SCN, leading to conflicting time signals to target tissues of the SCN. The present study explored in a rodent model of night-work the influence of food during the normal sleep period on the synchrony of gene expression between clock genes and metabolic genes in the liver. Male Wistar rats were exposed to forced activity for 8 h either during the rest phase (day) or during the active phase (night) by using a slow rotating wheel. In this shift work model food intake shifts spontaneously to the forced activity period, therefore the influence of food alone without induced activity was tested in other groups of animals that were fed ad libitum, or fed during their rest or active phase. Rats forced to be active and/or eating during their rest phase, inverted their daily peak of Per1, Bmal1 and Clock and lost the rhythm of Per2 in the liver, moreover NAMPT and metabolic genes such as Pparα lost their rhythm and thus their synchrony with clock genes. We conclude that shift work or food intake in the rest phase leads to desynchronization within the liver, characterized by misaligned temporal patterns of clock genes and metabolic genes. This may be the cause of the development of the metabolic syndrome and obesity in individuals engaged in shift work.

On-line HPLC Analysis System for Metabolism and Inhibition Studies in Precision-Cut Liver Slices

NARCIS (Netherlands)

van Midwoud, Paul M.; Janssen, Joost; Merema, M.T.; de Graaf, Inge A. M.; Groothuis, Geny M. M.; Verpoorte, Elisabeth

2011-01-01

A novel approach for on-line monitoring of drug metabolism in continuously perifused, precision-cut liver slices (PCLS) in a microfluidic system has been developed using high-performance liquid chromatography with UV detection (HPLC-UV). In this approach, PCLS are incubated in a microfluidic device

Investigation on liver fast metabolism with CT

International Nuclear Information System (INIS)

Huebener, K.H.; Schmitt, W.G.H.

1981-01-01

Measurements of the density of normal and diffusely diseased liver parenchyma show a significant difference only in fatty liver. A linear relationship between the fat content and physical density has been demonstrated. Computed tomographic densitometry of liver tissue correlates well with physical in vitro measurements of fat content and is sufficiently accurate for clinical use. Other types of liver diseases cannot be differentiated by densitometry, Lipolisis in fatty liver in chronic alcoholism alcohol withdrawal has been investigated. It has been found that a rate of decrease of the fatty degeneration of the liver equals to 1 percent/day. Fatty degeneration of the liver in acute pancreatitis and other diseases have been also investigated. CT densitometry of the liver should be considered as a useful routine clinical method to determine the fat content of liver. (author)

Investigation on liver fast metabolism with CT

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Huebener, K.H.; Schmitt, W.G.H. (Heidelberg Univ. (Germany, F.R.). Pathologisches Inst.)

1981-01-01

Measurements of the density of normal and diffusely diseased liver parenchyma show a significant difference only in fatty liver. A linear relationship between the fat content and physical density has been demonstrated. Computed tomographic densitometry of liver tissue correlates well with physical in vitro measurements of fat content and is sufficiently accurate for clinical use. Other types of liver diseases cannot be differentiated by densitometry, Lipolisis in fatty liver in chronic alcoholism alcohol withdrawal has been investigated. It has been found that a rate of decrease of the fatty degeneration of the liver equals to 1 percent/day. Fatty degeneration of the liver in acute pancreatitis and other diseases have been also investigated. CT densitometry of the liver should be considered as a useful routine clinical method to determine the fat content of liver.

Effects of insulin-like growth factor-I on bone metabolism in patients with liver cirrhosis

International Nuclear Information System (INIS)

Li Xiaohong; Gao Wenjin; Wang Mingtao; Hu Haiqiang

2006-01-01

To study the effects of serum insulin-like growth factor-I (IGF-I) on bone metabolism in liver cirrhosis, 44 patients with hepatic cirrhosis were divided into 3 groups according to disease severity (Child Pugh Score) and 38 healthy subjects served as controls. Serum levels of IGF-I and osteocalcin(BGP) were measured in all patients and controls. Results showed that levels of IGF-I, BGP, and BMD were lower significantly in patients with liver cirrhosis than that in controls. When the condition of cirrhosis more deteriorated, these changes became much lower significantly. Serum levels of BGP and BMD were positively correlated with IGF-I. The decreasing level of IGF-I might be an important factor causing osteoporosis in patients with liver cirrhosis. (authors)

Effects of Castration on Expression of Lipid Metabolism Genes in the Liver of Korean Cattle

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Myunggi Baik

2015-01-01

Full Text Available Castration induces the accumulation of body fat and deposition of intramuscular fat in Korean cattle, resulting in improved beef quality. However, little is known about the metabolic adaptations in the liver following castration. To understand changes in lipid metabolism following castration, hepatic expression levels of lipid metabolism genes were compared between Korean bulls and steers. Steers had higher (p<0.001 hepatic lipids contents and higher (p<0.01 mRNA levels of lipogenic acetyl-CoA carboxylase. This differential gene expression may, in part, contribute to increased hepatic lipid content following the castration of bulls. However, we found no differences in the hepatic expression levels of genes related to triglyceride synthesis (mitochondrial glycerol-3-phosphate acyltransferase, diacylglycerol O-acyltransferase 1 and 2 and fatty acid (FA oxidation (carnitine palmitoyltransferase 1A, C-4 to C-12 straight chain acyl-CoA dehydrogenase, very long chain acyl-CoA dehydrogenase between bulls and steers. No differences in gene expression for very-low-density lipoprotein (VLDL secretion, including apolipoprotein B mRNA and microsomal triglyceride transfer protein (MTTP protein, were observed in the liver although MTTP mRNA levels were higher in steers compared to bulls. In conclusion, FA synthesis may contribute to increased hepatic lipid deposition in steers following castration. However, hepatic lipid metabolism, including triglyceride synthesis, FA oxidation, and VLDL secretion, was not significantly altered by castration. Our results suggest that hepatic lipid metabolism does not significantly contribute to increased body fat deposition in steers following castration.

Gene polymorphisms of desaturase enzymes of polyunsaturated fatty acid metabolism and adiponutrin and the increased risk of nonalcoholic fatty liver disease

OpenAIRE

Manvi Vernekar; Deepak Amarapurkar; Kalpana Joshi; Rekha Singhal

2017-01-01

Nonalcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome (MetS). Adiponutrin gene polymorphisms have been associated with NAFLD worldwide. Polyunsaturated fatty acids (PUFAs) have been studied to have anti-inflammatory effects and plasma lipid lowering properties. PUFAs are endogenously synthesized with the help of delta-6-desaturase and delta-5-desaturase enzymes. They are encoded by FADS2 and FADS1 genes respectively. Polymorphisms in ...

The effect of experimental diabetes on phenylalanine metabolism in isolated liver cells.

OpenAIRE

Santana, M A; Fisher, M J; Bate, A J; Pogson, C I

1985-01-01

Chronic (10-day) diabetes was associated with increased metabolic flux through phenylalanine hydroxylase in isolated liver cells. This flux was stimulated by 0.1 microM-glucagon, but not by 10 microM-noradrenaline; 0.1 microM-insulin affected neither basal nor glucagon-stimulated flux. The increased rate of phenylalanine hydroxylation in diabetes was accompanied by parallel increases in enzyme activity (as measured with artificial cofactor) and immunoreactive-enzyme-protein content. In contra...

Failure of Chemotherapy in Hepatocellular Carcinoma Due to Impaired and Dysregulated Primary Liver Drug Metabolizing Enzymes and Drug Transport Proteins: What to Do?

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Ul Islam, Salman; Ahmed, Muhammad Bilal; Shehzad, Adeeb; Ul-Islam, Mazhar; Lee, Young Sup

2018-05-28

Most of the drugs are metabolized in the liver by the action of drug metabolizing enzymes. In hepatocellular carcinoma (HCC), primary drug metabolizing enzymes are severely dysregulated, leading to failure of chemotherapy. Sorafenib is the only standard systemic drug available, but it still presents certain limitations, and much effort is required to understand who is responsive and who is refractory to the drug. Preventive and therapeutic approaches other than systemic chemotherapy include vaccination, chemoprevention, liver transplantation, surgical resection, and locoregional therapies. This review details the dysregulation of primary drug metabolizing enzymes and drug transport proteins of the liver in HCC and their influence on chemotherapeutic drugs. Furthermore, it emphasizes the adoption of safe alternative therapeutic strategies to chemotherapy. The future of HCC treatment should emphasize the understanding of resistance mechanisms and the finding of novel, safe, and efficacious therapeutic strategies, which will surely benefit patients affected by advanced HCC. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Animal experiments to study the connection between the radioreaction of the RNA metabolism of the liver and the activity of the protein metabolism

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Peters, E

1973-02-05

After selective deep X-ray irradiation of rat livers with 200 KeV X-rays, an enhanced incorporation of tritium uridine into various RNA species is observed. The extent and the rate of the radioreaction could be modified by experimentally changing the metabolic status of the liver cells. Partial deproteinisation of the plasma by means of an exchange function lead to a marked rise in the RNA synthesis rate of the liver for a short period of time. Additional irradiation had an inhibiting and delaying effect on the induction-dependent increase in tritium uridine incorporation in the case of transfer-RNA and m-RNA, while there was an enhanced incorporation in the messenger RNA of the heavy ribosome and polymer fraction.

Basil extract inhibits the sulfotransferase mediated formation of DNA adducts of the procarcinogen 1′-hydroxyestragole by rat and human liver S9 homogenates and in HepG2 human hepatoma cells

NARCIS (Netherlands)

Jeurissen, S.M.F.; Punt, A.; Delatour, T.; Rietjens, I.M.C.M.

2008-01-01

The effects of a basil extract on the sulfation and concomitant DNA adduct formation of the proximate carcinogen 1′-hydroxyestragole were studied using rat and human liver S9 homogenates and the human hepatoma cell line HepG2. Basil was chosen since it contains the procarcinogen estragole that can

Metformin in gestational diabetes: the offspring follow-up (MiG TOFU): body composition and metabolic outcomes at 7–9 years of age

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Rush, Elaine C; Plank, Lindsay D; Lu, Jun; Obolonkin, Victor; Coat, Suzette

2018-01-01

Objective To compare body composition and metabolic outcomes at 7–9 years in offspring of women with gestational diabetes (GDM) randomized to metformin (±insulin) or insulin treatment during pregnancy. Research design and methods Children were assessed at 7 years in Adelaide (n=109/181) and 9 years in Auckland (n=99/396) by anthropometry, bioimpedance analysis (BIA), dual-energy X-ray absorptiometry (DXA), magnetic resonance imaging (MRI) (n=92/99) and fasting bloods (n=82/99). Results In the Adelaide subgroup, mothers were similar at enrollment. Women randomized to metformin versus insulin had higher treatment glycemia (p=0.002) and more infants with birth weight >90th percentile (20.7% vs 5.9%; p=0.029). At 7 years, there were no differences in offspring measures. In Auckland, at enrollment, women randomized to metformin had a higher body mass index (BMI) (p=0.08) but gained less weight during treatment (p=0.07). Offspring birth measures were similar. At 9 years, metformin offspring were larger by measures of weight, arm and waist circumferences, waist:height (p<0.05); BMI, triceps skinfold (p=0.05); DXA fat mass and lean mass (p=0.07); MRI abdominal fat volume (p=0.051). Body fat percent was similar between treatment groups by DXA and BIA. Abdominal fat percentages (visceral adipose tissue, subcutaneous adipose tissue and liver) were similar by MRI. Fasting glucose, triglyceride, insulin, insulin resistance, glycosylated hemoglobin (HbA1c), cholesterol, liver transaminases, leptin and adiponectin were similar. Conclusions Metformin or insulin for GDM was associated with similar offspring total and abdominal body fat percent and metabolic measures at 7–9 years. Metformin-exposed children were larger at 9 years. Metformin may interact with fetal environmental factors to influence offspring outcomes. PMID:29682291

Green tea polyphenols alter lipid metabolism in the livers of broiler chickens through increased phosphorylation of AMP-activated protein kinase.

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Jinbao Huang

Full Text Available Our previous results showed that green tea polyphenols (GTPs significantly altered the expression of lipid-metabolizing genes in the liver of chickens. However, the underlying mechanism was not elucidated. In this study, we further characterized how GTPs influence AMP-activated protein kinase (AMPK in the regulation of hepatic fat metabolism. Thirty-six male chickens were fed GTPs at a daily dose of 0, 80 or 160 mg/kg of body weight for 4 weeks. The results demonstrated that oral administration of GTPs significantly reduced hepatic lipid content and abdominal fat mass, enhanced the phosphorylation levels of AMPKα and ACACA, and altered the mRNA levels and enzymatic activities of lipid-metabolizing enzymes in the liver. These results suggested that the activation of AMPK is a potential mechanism by which GTPs regulate hepatic lipid metabolism in such a way that lipid synthesis is reduced and fat oxidation is stimulated.

Eicosapentaenoic Acid-Enriched Phosphatidylcholine Attenuated Hepatic Steatosis Through Regulation of Cholesterol Metabolism in Rats with Nonalcoholic Fatty Liver Disease.

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Liu, Yanjun; Shi, Di; Tian, Yingying; Liu, Yuntao; Zhan, Qiping; Xu, Jie; Wang, Jingfeng; Xue, Changhu

2017-02-01

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. Disturbed cholesterol metabolism plays a crucial role in the development of NAFLD. The present study was conducted to evaluate the effects of EPA-PC extracted from sea cucumber on liver steatosis and cholesterol metabolism in NAFLD. Male Wistar rats were randomly divided into seven groups (normal control group, model group, lovastatin group, low- and high-dose EPA groups, and low- and high-dose EPA-PC groups). Model rats were established by administering a diet containing 1% orotic acid. To determine the possible cholesterol metabolism promoting mechanism of EPA-PC, we analyzed the transcription of key genes and transcriptional factors involved in hepatic cholesterol metabolism. EPA-PC dramatically alleviated hepatic lipid accumulation, reduced the serum TC concentration, and elevated HDLC levels in NAFLD rats. Fecal neutral cholesterol excretion was also promoted by EPA-PC administration. Additionally, EPA-PC decreased the mRNA expression of hydroxymethyl glutaric acid acyl (HMGR) and cholesterol 7α-hydroxylase (CYP7A), and increased the transcription of sterol carrying protein 2 (SCP2). Moreover, EPA-PC stimulated the transcription of peroxisome proliferators-activated receptor α (PPARα) and adenosine monophosphate activated protein kinase (AMPK) as well as its modulators, liver kinase B1 (LKB1) and Ca 2+ /calmodulin-dependent kinase kinase (CAMKK). Based on the results, the promoting effects of EPA-PC on NAFLD may be partly associated with the suppression of cholesterol synthesis via HMGR inhibition and the enhancement of fecal cholesterol excretion through increased SCP2 transcription. The underlying mechanism may involve stimulation of PPARα and AMPK.

Indigofera suffruticosa Mill extracts up-regulate the expression of the π class of glutathione S-transferase and NAD(P)H: quinone oxidoreductase 1 in rat Clone 9 liver cells.

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Chen, Chun-Chieh; Liu, Chin-San; Li, Chien-Chun; Tsai, Chia-Wen; Yao, Hsien-Tsung; Liu, Te-Chung; Chen, Haw-Wen; Chen, Pei-Yin; Wu, Yu-Ling; Lii, Chong-Kuei; Liu, Kai-Li

2013-09-01

Because induction of phase II detoxification enzyme is important for chemoprevention, we study the effects of Indigofera suffruticosa Mill, a medicinal herb, on the expression of π class of glutathione S-transferase (GSTP) and NAD(P)H: quinone oxidoreductase 1 (NQO1) in rat Clone 9 liver cells. Both water and ethanolic extracts of I. suffruticosa significantly increased the expression and enzyme activities of GSTP and NQO1. I. suffruticosa extracts up-regulated GSTP promoter activity and the binding affinity of nuclear factor erythroid 2-related factor 2 (Nrf2) with the GSTP enhancer I oligonucleotide. Moreover, I. suffruticosa extracts increased nuclear Nrf2 accumulation as well as ARE transcriptional activity. The level of phospho-ERK was augmented by I. suffruticosa extracts, and the ERK inhibitor PD98059 abolished the I. suffruticosa extract-induced ERK activation and GSTP and NQO-1 expression. Moreover, I. suffruticosa extracts, especially the ethanolic extract increased the glutathione level in mouse liver and red blood cells as well as Clone 9 liver cells. The efficacy of I. suffruticosa extracts in induction of phase II detoxification enzymes and glutathione content implies that I. suffruticosa could be considered as a potential chemopreventive agent. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Effects of berberine on the recovery of rat liver xenobiotic-metabolizing enzymes after partial hepatectomy].

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Zverinsky, I V; Zverinskaya, H G; Sutsko, I P; Telegin, P G; Shlyahtun, A G

2015-01-01

We have studied the effect of berberine on the recovery processes of liver xenobiotic-metabolizing function during its compensatory growth after 70% partial hepatectomy. It was found the hepatic ability to metabolize foreign substances are not restored up to day 8. Administration of berberine (10 mg/kg intraperitoneally) for 6 days led to normalization of both cytochrome P450-dependent and flavin-containing monooxygenases. It is suggested that in the biotransformation of berberine involved not only cytochrome P450, but also flavin-containing monooxygenases.

The Metabolic Role of Gut Microbiota in the Development of Nonalcoholic Fatty Liver Disease and Cardiovascular Disease

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Marco Sanduzzi Zamparelli

2016-07-01

Full Text Available The prevalence of metabolic disorders, such as type 2 diabetes (T2D, obesity, and non-alcoholic fatty liver disease (NAFLD, which are common risk factors for cardiovascular disease (CVD, has dramatically increased worldwide over the last decades. Although dietary habit is the main etiologic factor, there is an imperfect correlation between dietary habits and the development of metabolic disease. Recently, research has focused on the role of the microbiome in the development of these disorders. Indeed, gut microbiota is implicated in many metabolic functions and an altered gut microbiota is reported in metabolic disorders. Here we provide evidence linking gut microbiota and metabolic diseases, focusing on the pathogenetic mechanisms underlying this association.

Association between serum CA 19-9 and metabolic syndrome: A cross-sectional study.

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Du, Rui; Cheng, Di; Lin, Lin; Sun, Jichao; Peng, Kui; Xu, Yu; Xu, Min; Chen, Yuhong; Bi, Yufang; Wang, Weiqing; Lu, Jieli; Ning, Guang

2017-11-01

Increasing evidence suggests that serum CA 19-9 is associated with abnormal glucose metabolism. However, data on the association between CA 19-9 and metabolic syndrome is limited. The aim of the present study was to investigate the association between serum CA 19-9 and metabolic syndrome. A cross-sectional study was conducted on 3641 participants aged ≥40 years from the Songnan Community, Baoshan District in Shanghai, China. Logistic regression analysis was used to evaluate the association between serum CA 19-9 and metabolic syndrome. Multivariate logistic regression analysis showed that compared with participants in the first tertile of serum CA 19-9, those in the second and third tertiles had increased odds ratios (OR) for prevalent metabolic syndrome (multivariate adjusted OR 1.46 [95% confidence interval {CI} 1.11-1.92] and 1.51 [95% CI 1.14-1.98]; P trend  = 0.005). In addition, participants with elevated serum CA 19-9 (≥37 U/mL) had an increased risk of prevalent metabolic syndrome compared with those with serum CA 19-9 metabolic syndrome. In order to confirm this association and identify potential mechanisms, prospective cohort and mechanic studies should be performed. © 2017 Ruijin Hospital, Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.

The effect of alterations in total coenzyme A on metabolic pathways in the liver and heart

International Nuclear Information System (INIS)

Schlosser, C.A.S.

1989-01-01

The first set of experiments involved in vitro experiments using primary cultures of rat hepatocytes. A range of conditions were developed which resulted in cell cultures with variations in total CoA over a range of 1.3 to 2.9 nmol/mg protein with identical hormonal activation which simulated metabolic stress. Elevations of total CoA levels above that of controls due to preincubation with cyanamide plus pantothenate were correlated with diminished rates of total ketone body production, 3-hydroxybutyrate production and ratios of 3 hydroxybutyrate/acetoactetate with palmitate as substrate. In contrast, cells with elevated total CoA levels had higher rates of [ 14 C] CO 2 production from radioactive palmitate which implied greater flux of acetyl CoA units into the TCA cycle and less to the pathway of ketogenesis. The second set of experiments were designed to alter total CoA levels in vivo by maintaining rats on a chronic ethanol diet with or without pantothenate-supplementation. The effect of alterations of CoA on mitochondrial metabolism was evaluated by measuring substrate oxidation rates in liver and heat mitochondria as well as ketone body production with palmitoyl-1-carnitine as substrate

Effects of phthalic acid esters on the liver and thyroid

International Nuclear Information System (INIS)

Hinton, R.H.; Mitchell, F.E.; Mann, A.; Chescoe, D.; Price, S.C.; Nunn, A.; Grasso, P.; Bridges, J.W.

1986-01-01

The effects, over periods from 3 days to 9 months of administration, of diets containing di-2-ethylhexyl phthalate are very similar to those observed in rats administered diets containing hypolipidemic drugs such as clofibrate. Changes occur in a characteristic order commencing with alterations in the distribution of lipid within the liver, quickly followed by proliferation of hepatic peroxisomes and induction of the specialized P-450 isoenzyme(s) catalyzing omega oxidation of fatty acids. There follows a phase of mild liver damage indicated by changes in incorporation of 3 H-thymidine into DNA, by induction of glucose-6-phosphatase activity and a loss of glycogen, eventually leading to the formation of enlarged lysosomes through autophagy and the accumulation of lipofuscin. Associated changes are found in the kidney and thyroid. The renal changes are limited to the proximal convoluted tubules and are generally similar to changes found in the liver. The effects on the thyroid are more marked. Although the levels of thyroxine in plasma fall to about half normal values, serum triiodothyronine remains close to normal values while the appearance of the thyroid varies, very marked hyperactivity being noted 7 days after commencement of treatment, this is less marked at 14 days, but even after 9 months treatment there is clear cut evidence for hyperactivity with colloid changes which indicate this has persisted for some time. The short-term in vivo hepatic effects of the three phthalate esters can be reproduced in hepatocytes in tissue culture. All three phthalate esters, as well as clofibrate, have early marked effects on the metabolism of fatty acids in isolated hepatocytes. A hypothesis is presented to explain the progress from these initial metabolic effects to the final formation of liver tumors

Chemical-induced coordinated and reciprocal changes in heme metabolism, cytochrome P450 synthesis and others in the liver of humans and rodents.

Science.gov (United States)

Yoshida, Takemi; Ashino, Takashi; Kobayashi, Yasuna

2016-01-01

A wide variety of drugs and chemicals have been shown to produce induction and inhibition of heme-metabolizing enzymes, and of drug-metabolizing enzymes, including cytochrome P450s (P450s, CYPs), which consist of many molecular species with lower substrate specificity. Such chemically induced enzyme alterations are coordinately or reciprocally regulated through the same and/or different signal transductions. From the toxicological point of view, these enzymatic changes sometimes exacerbate inherited diseases, such as precipitation of porphyrogenic attacks, although the induction of these enzymes is dependent on the animal species in response to the differences in the stimuli of the liver, where they are also metabolized by P450s. Since P450s are hemoproteins, their induction and/or inhibition by chemical compounds could be coordinately accompanied by heme synthesis and/or inhibition. This review will take a retrospective view of research works carried out in our department and current findings on chemical-induced changes in hepatic heme metabolism in many places, together with current knowledge. Specifically, current beneficial aspects of induction of heme oxygenase-1, a rate-limiting heme degradation enzyme, and its relation to reciprocal and coordinated changes in P450s, with special reference to CYP2A5, in the liver are discussed. Mechanistic studies are also summarized in relation to current understanding on these aspects. Emphasis is also paid to an example of a single chemical compound that could cause various changes by mediating multiple signal transduction systems. Current toxicological studies have been developing by utilizing a sophisticated "omics" technology and survey integrated changes in the tissues produced by the administration of a chemical, even in time- and dose-dependent manners. Toxicological studies are generally carried out step by step to determine and elucidate mechanisms produced by drugs and chemicals. Such approaches are correct

[The effect of halothane on the fructose metabolism in the liver].

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Götz, E; Scholz, R

1975-10-01

Glucose production from frutose (2 mmol) and fructolysis was studied in perfused rat liver. In the presence of halothane (0.5, 1.5, and 4.0 vol%) glucose production was inhibited, whereas lactate production was stimulated. Total fructose metabolism was unchanged. Since halogenated hydrocarbon compounds are known to inhibit the mitochondrial respiratory chain, it is concluded that glucose synthesis is inhibited due to decreased supply of energy-rich phosphates from oxidative phosphorylation. On the other hand, this depletion of energy may be partially compensated for by an increased extramitochondrial energy production due to fructolysis.

Oxidative Inactivation of Liver Mitochondria in High Fructose Diet-Induced Metabolic Syndrome in Rats: Effect of Glycyrrhizin Treatment.

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Sil, Rajarshi; Chakraborti, Abhay Sankar

2016-09-01

Metabolic syndrome is a serious health problem in the present world. Glycyrrhizin, a triterpenoid saponin of licorice (Glycyrrhiza glabra) root, has been reported to ameliorate the primary complications and hepatocellular damage in rats with the syndrome. In this study, we have explored metabolic syndrome-induced changes in liver mitochondrial function and effect of glycyrrhizin against the changes. Metabolic syndrome was induced in rats by high fructose (60%) diet for 6 weeks. The rats were then treated with glycyrrhizin (50 mg/kg body weight) by single intra-peritoneal injection. After 2 weeks of the treatment, the rats were sacrificed to collect liver tissue. Elevated mitochondrial ROS, lipid peroxidation and protein carbonyl, and decreased reduced glutathione content indicated oxidative stress in metabolic syndrome. Loss of mitochondrial inner membrane cardiolipin was observed. Mitochondrial complex I activity did not change but complex IV activity decreased significantly. Mitochondrial MTT reduction ability, membrane potential, phosphate utilisation and oxygen consumption decreased in metabolic syndrome. Reduced mitochondrial aconitase activity and increased aconitase carbonyl content suggested oxidative damage of the enzyme. Elevated Fe(2+) ion level in mitochondria might be associated with increased ROS generation in metabolic syndrome. Glycyrrhizin effectively attenuated mitochondrial oxidative stress and aconitase degradation, and improved electron transport chain activity. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Characterization of liver changes in ZSF1 rats, an animal model of metabolic syndrome

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Marta Borges-Canha

Full Text Available Background: The non-alcoholic fatty liver disease is the hepatic counterpart of the metabolic syndrome. ZSF1 rats are a metabolic syndrome animal model in which liver changes have not been described yet. Aim: The characterization of liver histological and innate immunity changes in ZSF1 rats. Methods: Five groups of rats were included (n = 7 each group: healthy Wistar-Kyoto control rats (Ctrl, hypertensive ZSF1 lean (Ln, ZSF1 obese rats with a normal diet (Ob, ZSF1 obese rates with a high-fat diet (Ob-HFD, and ZSF1 obese rats with low-intensity exercise training (Ob-Ex. The animals were sacrificed at 20 weeks of age, their livers were collected for: a measurements of the area of steatosis, fibrosis and inflammation (histomorphological analysis; and b innate immunity (toll-like receptor [TLR] 2, TLR4, peroxisome proliferator-activated receptor γ [PPARγ], toll interacting protein [TOLLIP] and inflammatory marker (tumor necrosis factor-alpha [TNFvs], interleukin 1 [IL-1] expression analysis by real-time PCR. Results: Ob, Ob-HFD and Ob-Ex were significantly heavier than Ln and Ctrl animals. Ob, Ob-HFD and Ob-Ex animals had impaired glucose tolerance and insulin resistance. ZSF1 Ob, Ob-HFD and Ob-Ex presented a higher degree of steatosis (3,5x; p < 0.05 than Ctrl or ZSF1 Ln rats. Steatohepatitis and fibrosis were not observed in any of the groups. No differences in expression were observed between Ctrl, Ln and Ob animals (except for the significantly higher expression of TOLLIP observed in the Ob vs Ln comparison. Ob-HFD and Ob-Ex rats showed increased expression of PPARγ and TOLLIP as compared to other groups. However, both groups also showed increased expression of TLR2 and TLR4. Nevertheless, this did not translate into a differential expression of TNFα or IL-1 in any of the groups. Conclusion: The ZSF1 model is associated with liver steatosis but not with steatohepatitis or a significantly increased expression of innate immunity or

Metabolism of lysergic acid diethylamide (LSD) to 2-oxo-3-hydroxy LSD (O-H-LSD) in human liver microsomes and cryopreserved human hepatocytes.

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Klette, K L; Anderson, C J; Poch, G K; Nimrod, A C; ElSohly, M A

2000-10-01

The metabolism of lysergic acid diethylamide (LSD) to 2-oxo-3-hydroxy lysergic acid diethylamide (O-H-LSD) was investigated in liver microsomes and cyropreserved hepatocytes from humans. Previous studies have demonstrated that O-H-LSD is present in human urine at concentrations 16-43 times greater than LSD, the parent compound. Additionally, these studies have determined that O-H-LSD is not generated during the specimen extraction and analytical processes or due to parent compound degradation in aqueous urine samples. However, these studies have not been conclusive in demonstrating that O-H-LSD is uniquely produced during in vivo metabolism. Phase I drug metabolism was investigated by incubating human liver microsomes and cryopreserved human hepatocytes with LSD. The reaction was quenched at various time points, and the aliquots were extracted using liquid partitioning and analyzed by liquid chromatography-mass spectrometry. O-H-LSD was positively identified in all human liver microsomal and human hepatocyte fractions incubated with LSD. In addition, O-H-LSD was not detected in any microsomal or hepatocyte fraction not treated with LSD nor in LSD specimens devoid of microsomes or hepatocytes. This study provides definitive evidence that O-H-LSD is produced as a metabolic product following incubation of human liver microsomes and hepatocytes with LSD.

Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

International Nuclear Information System (INIS)

Chen, Qi-Liang; Luo, Zhi; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

2013-01-01

Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

Energy Technology Data Exchange (ETDEWEB)

Chen, Qi-Liang; Luo, Zhi, E-mail: luozhi99@yahoo.com.cn; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

2013-07-15

Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

Effect of resveratrol on 17beta-estradiol sulfation by human hepatic and jejunal S9 and recombinant sulfotransferase 1E1.

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Furimsky, Anna M; Green, Carol E; Sharp, Lewanne E Hunt; Catz, Paul; Adjei, Araba A; Parman, Toufan; Kapetanovic, Izet M; Weinshilboum, Richard M; Iyer, Lalitha V

2008-01-01

The purpose of this study was to investigate the sulfation of resveratrol (3,5,4'-trihydroxystilbene) and its potential to exhibit drug-drug interactions via sulfation. The possible interaction of resveratrol with 17beta-estradiol (E2), a major estrogen hormone and prototypic substrate for sulfate conjugation, was studied. Resveratrol and E2 are both known to undergo sulfate conjugation catalyzed by human sulfotransferases (SULTs). Resveratrol is a phytoestrogen with mixed estrogen agonist/antagonist properties that is being developed as a chemopreventive agent. The sulfate conjugation of E2 and resveratrol were studied individually using S9 fractions from human liver and jejunum as well as recombinant human SULT isoforms. The sulfation of E2 (3-20 nM) was then investigated in the presence of various concentrations (0, 0.5, 1, and 2 microM) of resveratrol using the two S9 preparations as well as recombinant SULT1E1, the major isoform responsible for E2 sulfation. Resveratrol inhibited E2 sulfation with estimated K(i) values of 1.1 microM (liver), 0.6 microM (jejunum), and 2.3 microM (SULT1E1), concentrations that could be pharmacologically relevant. The results suggest that these phytoestrogens can potentially alter the homeostasis of estrogen levels. These findings also imply that resveratrol may inhibit the metabolism of other estrogen analogs or therapeutic agents such as ethinylestradiol or dietary components that are also substrates for SULT1E1.

MicroRNA-mediated regulation of glutathione and methionine metabolism and its relevance for liver disease.

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Lu, Shelly C; Mato, José M; Espinosa-Diez, Cristina; Lamas, Santiago

2016-11-01

The discovery of the microRNA (miRNA) family of small RNAs as fundamental regulators of post-transcriptional gene expression has fostered research on their importance in every area of biology and clinical medicine. In the particular area of liver metabolism and disease, miRNAs are gaining increasing importance. By focusing on two fundamental hepatic biosynthetic pathways, glutathione and methionine, we review recent advances on the comprehension of the role of miRNAs in liver pathophysiology and more specifically of models of hepatic cholestasis/fibrosis and hepatocellular carcinoma. Copyright © 2016 Elsevier Inc. All rights reserved.

A switch in hepatic cortisol metabolism across the spectrum of non alcoholic fatty liver disease.

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Adeeba Ahmed

Full Text Available Non alcoholic fatty liver disease (NAFLD is the hepatic manifestation of the metabolic syndrome. NAFLD represents a spectrum of liver disease ranging from reversible hepatic steatosis, to non alcoholic steato-hepatitis (NASH and cirrhosis. The potential role of glucocorticoids (GC in the pathogenesis of NAFLD is highlighted in patients with GC excess, Cushing's syndrome, who develop central adiposity, insulin resistance and in 20% of cases, NAFLD. Although in most cases of NAFLD, circulating cortisol levels are normal, hepatic cortisol availability is controlled by enzymes that regenerate cortisol (F from inactive cortisone (E (11β-hydroxysteroid dehydrogenase type 1, 11β-HSD1, or inactivate cortisol through A-ring metabolism (5α- and 5β-reductase, 5αR and 5βR.In vitro studies defined 11β-HSD1 expression in normal and NASH liver samples. We then characterised hepatic cortisol metabolism in 16 patients with histologically proven NAFLD compared to 32 obese controls using gas chromatographic analysis of 24 hour urine collection and plasma cortisol generation profile following oral cortisone.In patients with steatosis 5αR activity was increased, with a decrease in hepatic 11β-HSD1 activity. Total cortisol metabolites were increased in this group consistent with increased GC production rate. In contrast, in patients with NASH, 11β-HSD1 activity was increased both in comparison to patients with steatosis, and controls. Endorsing these findings, 11β-HSD1 mRNA and immunostaining was markedly increased in NASH patients in peri septal hepatocytes and within CD68 positive macrophages within inflamed cirrhotic septa.Patients with hepatic steatosis have increased clearance and decreased hepatic regeneration of cortisol and we propose that this may represent a protective mechanism to decrease local GC availability to preserve hepatic metabolic phenotype. With progression to NASH, increased 11β-HSD1 activity and consequent cortisol regeneration may

A switch in hepatic cortisol metabolism across the spectrum of non alcoholic fatty liver disease.

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Ahmed, Adeeba; Rabbitt, Elizabeth; Brady, Theresa; Brown, Claire; Guest, Peter; Bujalska, Iwona J; Doig, Craig; Newsome, Philip N; Hubscher, Stefan; Elias, Elwyn; Adams, David H; Tomlinson, Jeremy W; Stewart, Paul M

2012-01-01

Non alcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome. NAFLD represents a spectrum of liver disease ranging from reversible hepatic steatosis, to non alcoholic steato-hepatitis (NASH) and cirrhosis. The potential role of glucocorticoids (GC) in the pathogenesis of NAFLD is highlighted in patients with GC excess, Cushing's syndrome, who develop central adiposity, insulin resistance and in 20% of cases, NAFLD. Although in most cases of NAFLD, circulating cortisol levels are normal, hepatic cortisol availability is controlled by enzymes that regenerate cortisol (F) from inactive cortisone (E) (11β-hydroxysteroid dehydrogenase type 1, 11β-HSD1), or inactivate cortisol through A-ring metabolism (5α- and 5β-reductase, 5αR and 5βR). In vitro studies defined 11β-HSD1 expression in normal and NASH liver samples. We then characterised hepatic cortisol metabolism in 16 patients with histologically proven NAFLD compared to 32 obese controls using gas chromatographic analysis of 24 hour urine collection and plasma cortisol generation profile following oral cortisone. In patients with steatosis 5αR activity was increased, with a decrease in hepatic 11β-HSD1 activity. Total cortisol metabolites were increased in this group consistent with increased GC production rate. In contrast, in patients with NASH, 11β-HSD1 activity was increased both in comparison to patients with steatosis, and controls. Endorsing these findings, 11β-HSD1 mRNA and immunostaining was markedly increased in NASH patients in peri septal hepatocytes and within CD68 positive macrophages within inflamed cirrhotic septa. Patients with hepatic steatosis have increased clearance and decreased hepatic regeneration of cortisol and we propose that this may represent a protective mechanism to decrease local GC availability to preserve hepatic metabolic phenotype. With progression to NASH, increased 11β-HSD1 activity and consequent cortisol regeneration may serve to

Biofabrication of a three-dimensional liver micro-organ as an in vitro drug metabolism model.

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Chang, Robert; Emami, Kamal; Wu, Honglu; Sun, Wei

2010-12-01

In their normal in vivo matrix milieu, tissues assume complex well-organized three-dimensional architectures. Therefore, the primary aim in the tissue engineering design process is to fabricate an optimal analog of the in vivo scenario. This challenge can be addressed by applying emerging layered biofabrication approaches in which the precise configuration and composition of cells and bioactive matrix components can recapitulate the well-defined three-dimensional biomimetic microenvironments that promote cell-cell and cell-matrix interactions. Furthermore, the advent of and refinements in microfabricated systems can present physical and chemical cues to cells in a controllable and reproducible fashion unmatched with conventional cultures, resulting in the precise construction of engineered biomimetic microenvironments on the cellular length scale in geometries that are readily parallelized for high throughput in vitro models. As such, the convergence of layered solid freeform fabrication (SFF) technologies along with microfabrication techniques enables the creation of a three-dimensional micro-organ device to serve as an in vitro platform for cell culture, drug screening or to elicit further biological insights, particularly for NASA's interest in a flight-suitable high-fidelity microscale platform to study drug metabolism in space and planetary environments. The proposed model in this paper involves the combinatorial setup of an automated syringe-based, layered direct cell writing bioprinting process with micro-patterning techniques to fabricate a microscale in vitro device housing a chamber of bioprinted three-dimensional liver cell-encapsulated hydrogel-based tissue constructs in defined design patterns that biomimic the cell's natural microenvironment for enhanced biological functionality. In order to assess the structural formability and biological feasibility of such a micro-organ, reproducibly fabricated tissue constructs were biologically characterized for

Biofabrication of a three-dimensional liver micro-organ as an in vitro drug metabolism model

International Nuclear Information System (INIS)

Chang, Robert; Sun Wei; Emami, Kamal; Wu Honglu

2010-01-01

In their normal in vivo matrix milieu, tissues assume complex well-organized three-dimensional architectures. Therefore, the primary aim in the tissue engineering design process is to fabricate an optimal analog of the in vivo scenario. This challenge can be addressed by applying emerging layered biofabrication approaches in which the precise configuration and composition of cells and bioactive matrix components can recapitulate the well-defined three-dimensional biomimetic microenvironments that promote cell-cell and cell-matrix interactions. Furthermore, the advent of and refinements in microfabricated systems can present physical and chemical cues to cells in a controllable and reproducible fashion unmatched with conventional cultures, resulting in the precise construction of engineered biomimetic microenvironments on the cellular length scale in geometries that are readily parallelized for high throughput in vitro models. As such, the convergence of layered solid freeform fabrication (SFF) technologies along with microfabrication techniques enables the creation of a three-dimensional micro-organ device to serve as an in vitro platform for cell culture, drug screening or to elicit further biological insights, particularly for NASA's interest in a flight-suitable high-fidelity microscale platform to study drug metabolism in space and planetary environments. The proposed model in this paper involves the combinatorial setup of an automated syringe-based, layered direct cell writing bioprinting process with micro-patterning techniques to fabricate a microscale in vitro device housing a chamber of bioprinted three-dimensional liver cell-encapsulated hydrogel-based tissue constructs in defined design patterns that biomimic the cell's natural microenvironment for enhanced biological functionality. In order to assess the structural formability and biological feasibility of such a micro-organ, reproducibly fabricated tissue constructs were biologically characterized for

MR of the liver in Wilson`s disease; MRT der Leber bei Morbus Wilson

Energy Technology Data Exchange (ETDEWEB)

Vogl, T.J. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Steiner, S. [Klinikum Grosshadern, Radiologische Klinik und Poliklinik, Univ. Muenchen (Germany); Hammerstingl, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany); Schwarz, S. [Klinikum Grosshadern, Neurologische Klinik, Univ. Muenchen (Germany); Kraft, E. [Klinikum Grosshadern, Neurologische Klinik, Univ. Muenchen (Germany); Weinzierl, M. [Klinikum Grosshadern, 2. Medizinische Klinik, Univ. Muenchen (Germany); Felix, R. [Strahlenklinik und Poliklinik, Universitaetsklinikum Rudolf Virchow, Freie Univ. Berlin (Germany)

1994-01-01

To show that Wilson`s disease is one likely cause of multiple low-intensity nodules of the liver we obtained MR images in 16 patients with clinically and histopathologically confirmed Wilson`s disease. Corresponding to morphological changes MRI enabled the subdivision of the patients into two groups. Using a T{sub 2}-weighted spin-echo sequence (TR/TE=2000/45-90) liver parenchyma showed multiple tiny low-intensity-nodules surrounded by high-intensity septa in 10 out of 16 patients. 5 patients had also low-intensity nodules in T{sub 1}-weighted images (TR/TE=600/20). In patients of this group histopathology revealed liver cirrhosis (n=7) and fibrosis (n=2). Common feature of this patient group was marked inflammatory cell infiltration into fibrous septa, increase of copper concentration in liver parenchyma and distinct pathological changes of laboratory data. In the remaining 6 patients no pathological change of liver morphology was demonstrated by MRI corresponding to slight histopathological changes of parenchyma and normal laboratory data. As low-intensity nodules surrounded by high intensity septa can be demonstrated in patients with marked inflammatory infiltration of liver parenchyma MRI may help to define Wilson patients with poorer prognosis. In patients with low-intensity nodules of the liver and unknown cause of liver cirrhosis laboratory data and histopathology should be checked when searching for disorders of copper metabolism. (orig.) [Deutsch] Im Rahmen einer prospektiven Studie wurde die Leber bei 16 Patienten mit klinisch gesichertem Morbus Wilson magnetresonanztomographisch untersucht. Zum Einsatz kamen T{sub 1}- und T{sub 2}-gewichtete Spin-Echo-Sequenzen vor und nach Applikation von Gd-DTPA (0,1 mmol/kg KG). Anhand der MRT-Befunde konnten zwei unterschiedliche Patientenkollektive definiert werden. 10 Patienten wiesen in der T{sub 2}-gewichteten Sequenz hypointense Regeneratknoten auf und zeigten histopathologisch ausgepraegte Befunde einer

Alcohol extract of North American ginseng (Panax quinquefolius) reduces fatty liver, dyslipidemia, and other complications of metabolic syndrome in a mouse model.

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Singh, Ratnesh K; Lui, Edmund; Wright, David; Taylor, Adrian; Bakovic, Marica

2017-09-01

We investigated whether North American ginseng (Panax quinquefolius) could reduce development of the metabolic syndrome phenotype in a mouse model (ETKO) of the disease. Young ETKO mice have no disease but similar to humans start to develop the fatty liver, hypertriglyceridemia, obesity, and insulin resistance at 25-30 weeks of age, and the disease continues to progress with ageing. ETKO mice were orally given an ethanol extract of ginseng roots at 4 and 32 weeks of age. Treatments with ginseng eliminated the ETKO fatty liver, reduced hepatic and intestinal lipoprotein secretion, and reduced the level of circulating lipids. Improvements by ginseng treatments were manifested as a reduction in the expression of genes involved in the regulation of fatty acid and triglyceride (fat) synthesis and secretion by the lipoproteins on one hand, and the stimulation of fatty acid oxidation and triglyceride degradation by lipolysis on the other hand. These processes altogether improved glucose, fatty acid, and triglyceride metabolism, reduced liver fat load, and reversed the progression of metabolic syndrome. These data confirm that treatments with North American ginseng could alleviate metabolic syndrome through the maintenance of a better balance between glucose and fatty acid metabolism, lipoprotein secretion, and energy homeostasis in disease-prone states.

[Liver transplantation].

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Pompili, Maurizio; Mirante, Vincenzo Giorgio; Rapaccini, Gian Ludovico; Gasbarrini, Giovanni

2004-01-01

Liver transplantation represents the first choice treatment for patients with fulminant acute hepatitis and for patients with chronic liver disease and advanced functional failure. Patients in the waiting list for liver transplantation are classified according to the severity of their clinical conditions (evaluated using staging systems mostly based on hematochemical parameters related to liver function). This classification, together with the blood group and the body size compatibility, remains the main criterion for organ allocation. The main indications for liver transplantation are cirrhosis (mainly HCV-, HBV- and alcohol-related) and hepatocellular carcinoma emerging in cirrhosis in adult patients, biliary atresia and some inborn errors of metabolism in pediatric patients. In adults the overall 5-year survival ranges between 60 and 70%, in both American and European series. Even better results have been reported for pediatric patients: in fact, the 5-year survival rate for children ranges between 70 and 80% in the main published series. In this study we evaluated the main medical problems correlated with liver transplantation such as immunosuppressive treatment, acute and chronic rejection, infectious complications, the recurrence of the liver disease leading to transplantation, and cardiovascular and metabolic complications.

Single nucleotide polymorphisms of one-carbon metabolism and cancers of the esophagus, stomach, and liver in a Chinese population.

Directory of Open Access Journals (Sweden)

Shen-Chih Chang

Full Text Available One-carbon metabolism (folate metabolism is considered important in carcinogenesis because of its involvement in DNA synthesis and biological methylation reactions. We investigated the associations of single nucleotide polymorphisms (SNPs in folate metabolic pathway and the risk of three GI cancers in a population-based case-control study in Taixing City, China, with 218 esophageal cancer cases, 206 stomach cancer cases, 204 liver cancer cases, and 415 healthy population controls. Study participants were interviewed with a standardized questionnaire, and blood samples were collected after the interviews. We genotyped SNPs of the MTHFR, MTR, MTRR, DNMT1, and ALDH2 genes, using PCR-RFLP, SNPlex, or TaqMan assays. To account for multiple comparisons and reduce the chances of false reports, we employed semi-Bayes (SB shrinkage analysis. After shrinkage and adjusting for potential confounding factors, we found positive associations between MTHFR rs1801133 and stomach cancer (any T versus C/C, SB odds-ratio [SBOR]: 1.79, 95% posterior limits: 1.18, 2.71 and liver cancer (SBOR: 1.51, 95% posterior limits: 0.98, 2.32. There was an inverse association between DNMT1 rs2228612 and esophageal cancer (any G versus A/A, SBOR: 0.60, 95% posterior limits: 0.39, 0.94. In addition, we detected potential heterogeneity across alcohol drinking status for ORs relating MTRR rs1801394 to esophageal (posterior homogeneity P = 0.005 and stomach cancer (posterior homogeneity P = 0.004, and ORs relating MTR rs1805087 to liver cancer (posterior homogeneity P = 0.021. Among non-alcohol drinkers, the variant allele (allele G of these two SNPs was inversely associated with the risk of these cancers; while a positive association was observed among ever-alcohol drinkers. Our results suggest that genetic polymorphisms related to one-carbon metabolism may be associated with cancers of the esophagus, stomach, and liver. Heterogeneity across alcohol consumption status of

Liver-Specific Deletion of Protein-Tyrosine Phosphatase 1B (PTP1B) Improves Metabolic Syndrome and Attenuates Diet-Induced Endoplasmic Reticulum Stress

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Delibegovic, Mirela; Zimmer, Derek; Kauffman, Caitlin; Rak, Kimberly; Hong, Eun-Gyoung; Cho, You-Ree; Kim, Jason K.; Kahn, Barbara B.; Neel, Benjamin G.; Bence, Kendra K.

2009-01-01

OBJECTIVE—The protein tyrosine phosphatase PTP1B is a negative regulator of insulin signaling; consequently, mice deficient in PTP1B are hypersensitive to insulin. Because PTP1B−/− mice have diminished fat stores, the extent to which PTP1B directly regulates glucose homeostasis is unclear. Previously, we showed that brain-specific PTP1B−/− mice are protected against high-fat diet–induced obesity and glucose intolerance, whereas muscle-specific PTP1B−/− mice have increased insulin sensitivity independent of changes in adiposity. Here we studied the role of liver PTP1B in glucose homeostasis and lipid metabolism. RESEARCH DESIGN AND METHODS—We analyzed body mass/adiposity, insulin sensitivity, glucose tolerance, and lipid metabolism in liver-specific PTP1B−/− and PTP1Bfl/fl control mice, fed a chow or high-fat diet. RESULTS—Compared with normal littermates, liver-specific PTP1B−/− mice exhibit improved glucose homeostasis and lipid profiles, independent of changes in adiposity. Liver-specific PTP1B−/− mice have increased hepatic insulin signaling, decreased expression of gluconeogenic genes PEPCK and G-6-Pase, enhanced insulin-induced suppression of hepatic glucose production, and improved glucose tolerance. Liver-specific PTP1B−/− mice exhibit decreased triglyceride and cholesterol levels and diminished expression of lipogenic genes SREBPs, FAS, and ACC. Liver-specific PTP1B deletion also protects against high-fat diet–induced endoplasmic reticulum stress response in vivo, as evidenced by decreased phosphorylation of p38MAPK, JNK, PERK, and eIF2α and lower expression of the transcription factors C/EBP homologous protein and spliced X box-binding protein 1. CONCLUSIONS—Liver PTP1B plays an important role in glucose and lipid metabolism, independent of alterations in adiposity. Inhibition of PTP1B in peripheral tissues may be useful for the treatment of metabolic syndrome and reduction of cardiovascular risk in addition to

System-level perturbations of cell metabolism using CRISPR/Cas9

Energy Technology Data Exchange (ETDEWEB)

Jakočiūnas, Tadas [Technical Univ. of Denmark, Lyngby (Denmark); Jensen, Michael K. [Technical Univ. of Denmark, Lyngby (Denmark); Keasling, Jay D. [Technical Univ. of Denmark, Lyngby (Denmark); Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)

2017-03-30

CRISPR/Cas9 (clustered regularly interspaced palindromic repeats and the associated protein Cas9) techniques have made genome engineering and transcriptional reprogramming studies much more advanced and cost-effective. For metabolic engineering purposes, the CRISPR-based tools have been applied to single and multiplex pathway modifications and transcriptional regulations. The effectiveness of these tools allows researchers to implement genome-wide perturbations, test model-guided genome editing strategies, and perform transcriptional reprogramming perturbations in a more advanced manner than previously possible. In this mini-review we highlight recent studies adopting CRISPR/Cas9 for systems-level perturbations and model-guided metabolic engineering.

Serum vaspin level as a predictive indicator in the amelioration of fatty liver and metabolic disturbance in patients with severe obesity after laparoscopic vertical banded gastroplasty.

Science.gov (United States)

Wang, Yong; Yu, Zong-Fan; Cheng, Yun-Sheng; Jia, Ben-Li; Yu, Gang; Yin, Xiao-Qiang; Wang, Yang

2017-07-01

This study is all about predicting the value of serum vaspin level in the amelioration of fatty liver and metabolic disturbance in patients with severe obesity after laparoscopic vertical banded gastroplasty (LVBG). A total of 164 patients (from January 2012 to May 2015) with severe obesity were chosen and performed LVBG. Enzyme-linked immunosorbent assay was performed to detect the serum vaspin level. The patients were given a biochemical automatic analyzer to measure the biochemical indicators. Homeostasis model assessment (HOMA) helps in the calculation of fasting insulin level (FINS) and insulin resistance (IR). The changes in fatty liver were examined by computed tomography (CT). Receiver operating characteristic curve is used to increase the predictive value of serum vaspin level in the amelioration of liver function and disturbances in the metabolism. Weight, BMI, waist circumference, serum vaspin level, and triglyceride (TG) decreased, but CT value of liver increased at 4th, 7th, and 12th month after surgery. After the 7th and 12th month period of surgery, the alanine aminotransferase, aspartate aminotransferase, FINS, and HOMA-IR reduced in the patients (P fatty liver and metabolic disturbance. This study proves that the serum vaspin level serves as a predictive indicator in the amelioration of fatty liver and metabolic disturbance in patients with severe obesity after LVBG.

Comprehensive Evaluation for Substrate Selectivity of Cynomolgus Monkey Cytochrome P450 2C9, a New Efavirenz Oxidase.

Science.gov (United States)

Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Uehara, Shotaro; Shimizu, Makiko; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

2015-07-01

Cynomolgus monkeys are widely used as primate models in preclinical studies, because of their evolutionary closeness to humans. In humans, the cytochrome P450 (P450) 2C enzymes are important drug-metabolizing enzymes and highly expressed in livers. The CYP2C enzymes, including CYP2C9, are also expressed abundantly in cynomolgus monkey liver and metabolize some endogenous and exogenous substances like testosterone, S-mephenytoin, and diclofenac. However, comprehensive evaluation regarding substrate specificity of monkey CYP2C9 has not been conducted. In the present study, 89 commercially available drugs were examined to find potential monkey CYP2C9 substrates. Among the compounds screened, 20 drugs were metabolized by monkey CYP2C9 at a relatively high rates. Seventeen of these compounds were substrates or inhibitors of human CYP2C9 or CYP2C19, whereas three drugs were not, indicating that substrate specificity of monkey CYP2C9 resembled those of human CYP2C9 or CYP2C19, with some differences in substrate specificities. Although efavirenz is known as a marker substrate for human CYP2B6, efavirenz was not oxidized by CYP2B6 but by CYP2C9 in monkeys. Liquid chromatography-mass spectrometry analysis revealed that monkey CYP2C9 and human CYP2B6 formed the same mono- and di-oxidized metabolites of efavirenz at 8 and 14 positions. These results suggest that the efavirenz 8-oxidation could be one of the selective markers for cynomolgus monkey CYP2C9 among the major three CYP2C enzymes tested. Therefore, monkey CYP2C9 has the possibility of contributing to limited specific differences in drug oxidative metabolism between cynomolgus monkeys and humans. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

Changes in energy metabolism of the juvenile Fasciola hepatica during its development in the liver parenchyma

NARCIS (Netherlands)

Tielens, A.G.M.; Heuvel, J.M. van den; Bergh, S.G. van den

1982-01-01

Juvenile Fasciola hepatica at different stages of development were isolated from the liver parenchyma of experimentally infected rats. Their energy metabolism was studied by incubation with D-[16-14C]glucose and compared with that of juveniles isolated immediately after in vitro emergence from the

Comparative liver accumulation of dioxin-like compounds in sheep and cattle: Possible role of AhR-mediated xenobiotic metabolizing enzymes.

Science.gov (United States)

Girolami, F; Spalenza, V; Benedetto, A; Manzini, L; Badino, P; Abete, M C; Nebbia, C

2016-11-15

PCDDs, PCDFs, and PCBs are persistent organic pollutants (POPs) that accumulate in animal products and may pose serious health problems. Those able to bind the aryl hydrocarbon receptor (AhR), eliciting a plethora of toxic responses, are defined dioxin-like (DL) compounds, while the remainders are called non-DL (NDL). An EFSA opinion has highlighted the tendency of ovine liver to specifically accumulate DL-compounds to a greater extent than any other farmed ruminant species. To examine the possible role in such an accumulation of xenobiotic metabolizing enzymes (XME) involved in DL-compound biotransformation, liver samples were collected from ewes and cows reared in an area known for low dioxin contamination. A related paper reported that sheep livers had about 5-fold higher DL-compound concentrations than cattle livers, while the content of the six marker NDL-PCBs did not differ between species. Specimens from the same animals were subjected to gene expression analysis for AhR, AhR nuclear translocator (ARNT) and AhR-dependent oxidative and conjugative pathways; XME protein expression and activities were also investigated. Both AhR and ARNT mRNA levels were about 2-fold lower in ovine samples and the same occurred for CYP1A1 and CYP1A2, being approximately 3- and 9-fold less expressed in sheep compared to cattle, while CYP1B1 could be detectable in cattle only. The results of the immunoblotting and catalytic activity (most notably EROD) measurements of the CYP1A family enzymes were in line with the gene expression data. By contrast, phase II enzyme expression and activities in sheep were higher (UGT1A) or similar (GSTA1, NQO1) to those recorded in cattle. The overall low expression of CYP1 family enzymes in the sheep is in line with the observed liver accumulation of DL-compounds and is expected to affect the kinetics and the dynamics of other POPs such as many polycyclic aromatic hydrocarbons, as well as of toxins (e.g. aflatoxins) or drugs (e.g. benzimidazole

Liver function evaluation in leptospirosis with colloidal gold 1 9 8 Au

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Walber Miranda Silva

1977-12-01

Full Text Available Eight patients with leptospirosis were studied with colloidal gold 1 9 8 Au. The radiocolloidal hepatic distribution was altered, presenting a non-homogeneous tiver concentration in seven cases, and a minute to moderate splenic visualization in five. Two patients presented doubtful splenic image, and one seemed to be normal. Liver scanning with colloidal gold 1 9 8 Au is demonstra ted to be a good liver function test.Oito pacientes com Leptospirose foram investigados com ouro coloidal radioativo (1 9 8 Au. A distribuição intrahepática do radiocoloide era alterada, apresentando uma concentração hepática não-homogênea em 7 casos, e visualização esp/ênica de mínima a moderada em 5. Dois tinham dúvida quanto à imagem do baço, e um parecia normal. A cintigrafia hepática com ouro coloidai radioativo (1 9 8 Au é demonstrada ser um bom teste de função hepática.

PGC-1α functions as a co-suppressor of XBP1s to regulate glucose metabolism

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Jaemin Lee

2018-01-01

Full Text Available Objective: Peroxisome proliferator-activated receptor γ (PPARγ coactivator-1α (PGC-1α promotes hepatic gluconeogenesis by activating HNF4α and FoxO1. PGC-1α expression in the liver is highly elevated in obese and diabetic conditions, leading to increased hepatic glucose production. We previously showed that the spliced form of X-box binding protein 1 (XBP1s suppresses FoxO1 activity and hepatic gluconeogenesis. The shared role of PGC-1α and XBP1s in regulating FoxO1 activity and gluconeogenesis led us to investigate the probable interaction between PGC-1α and XBP1s and its role in glucose metabolism. Methods: We investigated the biochemical interaction between PGC-1α and XBP1s and examined the role of their interaction in glucose homeostasis using animal models. Results: We show that PGC-1α interacts with XBP1s, which plays an anti-gluconeogenic role in the liver by suppressing FoxO1 activity. The physical interaction between PGC-1α and XBP1s leads to suppression of XBP1s activity rather than its activation. Upregulating PGC-1α expression in the liver of lean mice lessens XBP1s protein levels, and reducing PGC-1α levels in obese and diabetic mouse liver restores XBP1s protein induction. Conclusions: Our findings reveal a novel function of PGC-1α as a suppressor of XBP1s function, suggesting that hepatic PGC-1α promotes gluconeogenesis through multiple pathways as a co-activator for HNF4α and FoxO1 and also as a suppressor for anti-gluconeogenic transcription factor XBP1s. Keywords: PGC-1α, XBP1s, Glucose homeostasis, ER stress, UPR, Insulin resistance

[Diabetes in liver cirrhosis].

Science.gov (United States)

García-Compeán, Diego; Jáquez-Quintana, Joel O; González-González, José A; Lavalle-González, Fernando J; Villarreal-Pérez, Jesús Z; Maldonado-Garza, Hector J

2013-01-01

The prevalence of overt diabetes mellitus (DM) in liver cirrhosis is about 30%. However, DM or impaired glucose tolerance can be observed in 90% after an oral glucose tolerance test in patients with normal fasting plasma glucose. Type 2 DM may produce cirrhosis, whereas DM may be a complication of cirrhosis. The latter is known as «hepatogenous diabetes». Overt and subclinical DM is associated with liver complications and death in cirrhotic patients. Treating diabetes is difficult in cirrhotic patients because of the metabolic impairments due to liver disease and because the most appropriate pharmacologic treatment has not been defined. It is also unknown if glycemic control with hypoglycemic agents has any impact on the course of the liver disease. Copyright © 2013 Elsevier España, S.L. y AEEH y AEG. All rights reserved.

The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

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Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

1981-01-01

The effects of space flight conditions on the activities of certain enzymes regulating carbohydrate and lipid metabolism in rat liver are investigated in an attempt to account for the losses in body weight observed during space flight despite preflight caloric consumption. Liver samples were analyzed for the activities of 32 cytosolic and microsomal enzymes as well as hepatic glycogen and individual fatty acid levels for ground control rats and rats flown on board the Cosmos 936 biosatellite under normal space flight conditions and in centrifuges which were sacrificed upon recovery or 25 days after recovery. Significant decreases in the activities of glycogen phosphorylase, alpha-glycerol phosphate acyl transferase, diglyceride acyl transferase, aconitase and 6-phosphogluconate dehydrogenase and an increase in palmitoyl CoA desaturase are found in the flight stationary relative to the flight contrifuged rats upon recovery, with all enzymes showing alterations returning to normal values 25 days postflight. The flight stationary group is also observed to be characterized by more than twice the amount of liver glycogen of the flight centrifuged group as well as a significant increase in the ratio of palmitic to palmitoleic acid. Results thus indicate metabolic changes which may be involved in the mechanism of weight loss during weightlessness, and demonstrate the equivalence of centrifugation during space flight to terrestrial gravity.

Metabolism of six CYP probe substrates in fetal hepatocytes

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Abdul Naveed Shaik

2016-06-01

Full Text Available Cytochrome P-450 (CYP are the most common drug metabolizing enzymes and are abundantly expressed in liver apart from kidney, lungs, intestine, brain etc. Their expression levels change with physiological conditions and disease states. The expression of these CYPs is less in human foetus and neonates compared to adults, which results in lower clearance of xenobiotics in infants and neonates compared to adults. Hepatocytes are the cells which are largely used to study these CYPs. We have isolated hepatocytes from aborted foetus to study the metabolism of six probe substrates: phenacetin, diclofenac, S-mephenytoin, dextromethorphan, nifedipine and testosterone. The results obtained show the expression of various CYPs (CYP1A2, CYP2C19, CYP2C9, CYP2D6, and CYP3A4 in human foetus and their involvement in metabolism of CYP probe substrates.

Metabolic fingerprints of serum, brain, and liver are distinct for mice with cerebral and noncerebral malaria: a ¹H NMR spectroscopy-based metabonomic study.

Science.gov (United States)

Ghosh, Soumita; Sengupta, Arjun; Sharma, Shobhona; Sonawat, Haripalsingh M

2012-10-05

Cerebral malaria (CM) is a life-threatening disease in humans caused by Plasmodium falciparum, leading to high mortality. Plasmodium berghei ANKA (PbA) infection in C57Bl/6 mice induces pathologic symptoms similar to that in human CM. However, experimental CM incidence in mice is variable, and there are no known metabolic correlates/fingerprints for the animals that develop CM. Here, we have used (1)H NMR-based metabonomics to investigate the metabolic changes in the mice with CM with respect to the mice that have noncerebral malaria (NCM) of the same batchmates with identical genetic backgrounds and infected simultaneously. The metabolic profile of the infected mice (both CM and NCM) was separately compared with the metabolite profile of uninfected control mice of same genetic background. The objective of this study was to search for metabolic changes/fingerprints of CM and identify the pathways that might be differentially altered in mice that succumbed to CM. The results show that brain, liver, and sera exhibit unique metabolic fingerprints for CM over NCM mice. Some of the major fingerprints are increased level of triglycerides, VLDL-cholesterol in sera of CM mice, and decreased levels of glutamine in the sera concomitant with increased levels of glutamine in the brain of the mice with CM. Moreover, glycerophosphocholine is decreased in both the brain and the liver of animals with CM, and myo-inositol and histamine are increased in the liver of CM mice. The metabolic fingerprints in brain, sera, and liver of mice with CM point toward perturbation in the ammonia detoxification pathway and perturbation in lipid and choline metabolism in CM specifically. The study helps us to understand the severity of CM over NCM and in unrevealing the specific metabolic pathways that are compromised in CM.

Occurrence of lipids in the liver of the hypertriglyceridemic rats

Czech Academy of Sciences Publication Activity Database

Zemanová, Zdeňka; Strnadová, Miluše; Jirsová, Z.; Klusoňová, Petra

2009-01-01

Roč. 153, č. 1 (2009), s. 37-40 ISSN 1213-8118 R&D Projects: GA AV ČR(CZ) KJB500110703 Institutional research plan: CEZ:AV0Z50110509 Keywords : lipid histochemistry * liver glucocorticoid metabolism * Prague Hereditary Hypertriglyceridemic rats Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition

Metabolism of 64Cu and transfer of 125I-MT in the bearing liver ascites tumor (H22) mice

International Nuclear Information System (INIS)

Huai Qing; Fang Xingwang; Wang Wenqing

1998-01-01

The metabolism of 64 Cu in some tissues of the bearing liver ascites tumor mice has been studied. The liver in normal and tumor bearing mice preferentially accumulates intravenous injection copper, however, the liver in the later mice accumulates much less copper than that of the former. It suggests that in the bearing ascites tumor mice, ascites tumor influences the metabolism of copper. It is found that the content of 64 Cu in the tumor cell is more than 85% in ascites tumor. Gel filtration profile of mice liver homogenate on Sephadex G-75 shows that injected 64 Cu is mainly bound with metallothionein. The tissues uptake of 125 I-labelled (Cd, Zn)-MT which is given in abdominal cavity are also reported. Of the tissues studied, the ascites tumor and kidney accumulate the highest concentration of given 125 I-MT, since over 20% of entire dose accumulated in them. After 125 I-MT is given, it soon goes into ascites tumor, and reaches the maximum in ascites as well as in tumor cell. Therefore, 125 I-MT can go through the membrane of tumor cell and reaches in the tumor cell

Serum glucose and liver glycogen in gamma irradiated rats

International Nuclear Information System (INIS)

Ahlersova, E.; Ahlers, I.; Molcanova, A.

1988-01-01

Overnight fasted male rats of Wistar strain were irradiated with single whole-body doses of 4.78-7.17-9.57 and 14.35 Gy of gamma rays. After decapitation at intervals 1-28 d (4.78 and 7.17 Gy), 1-7 d (9.57 Gy) and 1-3 d (14.35 Gy) glucose concentration in serum and glycogen concentration in liver of irradiated and non-irradiated animals were determined. The higher was radiation dose the more expressive extent and depth of changes (hyperglycemia, accumulation of glycogen) occured. Blood glucose and liver glycogen may serve as a reliable and dose-dependent biological indicators of metabolic changes in irradiated rats. (author)

The effect of short-term fasting on liver and skeletal muscle lipid, glucose, and energy metabolism in healthy women and men

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Browning, Jeffrey D.; Baxter, Jeannie; Satapati, Santhosh; Burgess, Shawn C.

2012-01-01

Fasting promotes triglyceride (TG) accumulation in lean tissues of some animals, but the effect in humans is unknown. Additionally, fasting lipolysis is sexually dimorphic in humans, suggesting that lean tissue TG accumulation and metabolism may differ between women and men. This study investigated lean tissue TG content and metabolism in women and men during extended fasting. Liver and muscle TG content were measured by magnetic resonance spectroscopy during a 48-h fast in healthy men and women. Whole-body and hepatic carbohydrate, lipid, and energy metabolism were also evaluated using biochemical, calorimetric, and stable isotope tracer techniques. As expected, postabsorptive plasma fatty acids (FAs) were higher in women than in men but increased more rapidly in men with the onset of early starvation. Concurrently, sexual dimorphism was apparent in lean tissue TG accumulation during the fast, occurring in livers of men but in muscles of women. Despite differences in lean tissue TG distribution, men and women had identical fasting responses in whole-body and hepatic glucose and oxidative metabolism. In conclusion, TG accumulated in livers of men but in muscles of women during extended fasting. This sexual dimorphism was related to differential fasting plasma FA concentrations but not to whole body or hepatic utilization of this substrate. PMID:22140269

Maternal diets deficient in folic acid and related methyl donors modify mechanisms associated with lipid metabolism in the fetal liver of the rat.

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McNeil, Christopher J; Hay, Susan M; Rucklidge, Garry J; Reid, Martin D; Duncan, Gary J; Rees, William D

2009-11-01

Previously we have examined the effects of diets deficient in folic acid ( - F) or folate deficient with low methionine and choline ( - F LM LC) on the relative abundance of soluble proteins in the liver of the pregnant rat. In the present study we report the corresponding changes in the fetal liver at day 21 of gestation. The abundance of eighteen proteins increased when dams were fed the - F diet. When dams were fed the - F LM LC diet, thirty-three proteins increased and eight decreased. Many of the differentially abundant proteins in the fetal liver could be classified into the same functional groups as those previously identified in the maternal liver, namely protein synthesis, metabolism, lipid metabolism and proteins associated with the cytoskeleton and endoplasmic reticulum. The pattern was consistent with reduced cell proliferation in the - F LM LC group but not in the - F group. Metabolic enzymes associated with lipid metabolism changed in both the - F and - F LM LC groups. The mRNA for carnitine palmitoyl transferase were up-regulated and CD36 (fatty acid translocase) down-regulated in the - F group, suggesting increased mitochondrial oxidation of fatty acids as an indirect response to altered maternal lipid metabolism. In the - F LM LC group the mRNA for acetyl CoA carboxylase was down-regulated, suggesting reduced fatty acid synthesis. The mRNA for transcriptional regulators including PPARalpha and sterol response element-binding protein-1c were unchanged. These results suggest that an adequate supply of folic acid and the related methyl donors may benefit fetal development directly by improving lipid metabolism in fetal as well as maternal tissues.

Lack of significant metabolic abnormalities in mice with liver-specific disruption of 11β-hydroxysteroid dehydrogenase type 1.

LENUS (Irish Health Repository)

Lavery, Gareth G

2012-07-01

Glucocorticoids (GC) are implicated in the development of metabolic syndrome, and patients with GC excess share many clinical features, such as central obesity and glucose intolerance. In patients with obesity or type 2 diabetes, systemic GC concentrations seem to be invariably normal. Tissue GC concentrations determined by the hypothalamic-pituitary-adrenal (HPA) axis and local cortisol (corticosterone in mice) regeneration from cortisone (11-dehydrocorticosterone in mice) by the 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme, principally expressed in the liver. Transgenic mice have demonstrated the importance of 11β-HSD1 in mediating aspects of the metabolic syndrome, as well as HPA axis control. In order to address the primacy of hepatic 11β-HSD1 in regulating metabolism and the HPA axis, we have generated liver-specific 11β-HSD1 knockout (LKO) mice, assessed biomarkers of GC metabolism, and examined responses to high-fat feeding. LKO mice were able to regenerate cortisol from cortisone to 40% of control and had no discernible difference in a urinary metabolite marker of 11β-HSD1 activity. Although circulating corticosterone was unaltered, adrenal size was increased, indicative of chronic HPA stimulation. There was a mild improvement in glucose tolerance but with insulin sensitivity largely unaffected. Adiposity and body weight were unaffected as were aspects of hepatic lipid homeostasis, triglyceride accumulation, and serum lipids. Additionally, no changes in the expression of genes involved in glucose or lipid homeostasis were observed. Liver-specific deletion of 11β-HSD1 reduces corticosterone regeneration and may be important for setting aspects of HPA axis tone, without impacting upon urinary steroid metabolite profile. These discordant data have significant implications for the use of these biomarkers of 11β-HSD1 activity in clinical studies. The paucity of metabolic abnormalities in LKO points to important compensatory effects by HPA

The mouse liver displays daily rhythms in the metabolism of phospholipids and in the activity of lipid synthesizing enzymes.

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Gorné, Lucas D; Acosta-Rodríguez, Victoria A; Pasquaré, Susana J; Salvador, Gabriela A; Giusto, Norma M; Guido, Mario Eduardo

2015-02-01

The circadian system involves central and peripheral oscillators regulating temporally biochemical processes including lipid metabolism; their disruption leads to severe metabolic diseases (obesity, diabetes, etc). Here, we investigated the temporal regulation of glycerophospholipid (GPL) synthesis in mouse liver, a well-known peripheral oscillator. Mice were synchronized to a 12:12 h light-dark (LD) cycle and then released to constant darkness with food ad libitum. Livers collected at different times exhibited a daily rhythmicity in some individual GPL content with highest levels during the subjective day. The activity of GPL-synthesizing/remodeling enzymes: phosphatidate phosphohydrolase 1 (PAP-1/lipin) and lysophospholipid acyltransferases (LPLATs) also displayed significant variations, with higher levels during the subjective day and at dusk. We evaluated the temporal regulation of expression and activity of phosphatidylcholine (PC) synthesizing enzymes. PC is mainly synthesized through the Kennedy pathway with Choline Kinase (ChoK) as a key regulatory enzyme or through the phosphatidylethanolamine (PE) N-methyltransferase (PEMT) pathway. The PC/PE content ratio exhibited a daily variation with lowest levels at night, while ChoKα and PEMT mRNA expression displayed maximal levels at nocturnal phases. Our results demonstrate that mouse liver GPL metabolism oscillates rhythmically with a precise temporal control in the expression and/or activity of specific enzymes.

Mice with chimeric livers are an improved model for human lipoprotein metabolism.

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Ellis, Ewa C S; Naugler, Willscott Edward; Nauglers, Scott; Parini, Paolo; Mörk, Lisa-Mari; Jorns, Carl; Zemack, Helen; Sandblom, Anita Lövgren; Björkhem, Ingemar; Ericzon, Bo-Göran; Wilson, Elizabeth M; Strom, Stephen C; Grompe, Markus

2013-01-01

Rodents are poor model for human hyperlipidemias because total cholesterol and low density lipoprotein levels are very low on a normal diet. Lipoprotein metabolism is primarily regulated by hepatocytes and we therefore assessed whether chimeric mice extensively repopulated with human cells can model human lipid and bile acid metabolism. FRG [ F ah(-/-) R ag2(-/-)Il2r g (-/-)]) mice were repopulated with primary human hepatocytes. Serum lipoprotein lipid composition and distribution (VLDL, LDL, and HDL) was analyzed by size exclusion chromatography. Bile was analyzed by LC-MS or by GC-MS. RNA expression levels were measured by quantitative RT-PCR. Chimeric mice displayed increased LDL and VLDL fractions and a lower HDL fraction compared to wild type, thus significantly shifting the ratio of LDL/HDL towards a human profile. Bile acid analysis revealed a human-like pattern with high amounts of cholic acid and deoxycholic acid (DCA). Control mice had only taurine-conjugated bile acids as expcted, but highly repopulated mice had glycine-conjugated cholic acid as found in human bile. RNA levels of human genes involved in bile acid synthesis including CYP7A1, and CYP27A1 were significantly upregulated as compared to human control liver. However, administration of recombinant hFGF19 restored human CYP7A1 levels to normal. Humanized-liver mice showed a typical human lipoprotein profile with LDL as the predominant lipoprotein fraction even on a normal diet. The bile acid profile confirmed presence of an intact enterohepatic circulation. Although bile acid synthesis was deregulated in this model, this could be fully normalized by FGF19 administration. Taken together these data indicate that chimeric FRG-mice are a useful new model for human lipoprotein and bile-acid metabolism.

Hepatoselective Nitric Oxide (NO) Donors, V-PYRRO/NO and V-PROLI/NO, in Nonalcoholic Fatty Liver Disease: A Comparison of Antisteatotic Effects with the Biotransformation and Pharmacokinetics.

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Kus, Kamil; Walczak, Maria; Maslak, Edyta; Zakrzewska, Agnieszka; Gonciarz-Dytman, Anna; Zabielski, Piotr; Sitek, Barbara; Wandzel, Krystyna; Kij, Agnieszka; Chabowski, Adrian; Holland, Ryan J; Saavedra, Joseph E; Keefer, Larry K; Chlopicki, Stefan

2015-07-01

V-PYRRO/NO [O(2)-vinyl-1-(pyrrolidin-1-yl)diazen-1-ium-1,2-diolate] and V-PROLI/NO (O2-vinyl-[2-(carboxylato)pyrrolidin-1-yl]diazen-1-ium-1,2-diolate), two structurally similar diazeniumdiolate derivatives, were designed as liver-selective prodrugs that are metabolized by cytochrome P450 isoenzymes, with subsequent release of nitric oxide (NO). Yet, their efficacy in the treatment of nonalcoholic fatty liver disease (NAFLD) and their comparative pharmacokinetic and metabolic profiles have not been characterized. The aim of the present work was to compare the effects of V-PYRRO/NO and V-PROLI/NO on liver steatosis, glucose tolerance, and liver fatty acid composition in C57BL/6J mice fed a high-fat diet, as well as to comprehensively characterize the ADME (absorption, distribution, metabolism and excretion) profiles of both NO donors. Despite their similar structure, V-PYRRO/NO and V-PROLI/NO showed differences in pharmacological efficacy in the murine model of NAFLD. V-PYRRO/NO, but not V-PROLI/NO, attenuated liver steatosis, improved glucose tolerance, and favorably modified fatty acid composition in the liver. Both compounds were characterized by rapid absorption following i.p. administration, rapid elimination from the body, and incomplete bioavailability. However, V-PYRRO/NO was eliminated mainly by the liver, whereas V-PROLI/NO was excreted mostly in unchanged form by the kidney. V-PYRRO/NO was metabolized by CYP2E1, CYP2C9, CYP1A2, and CYP3A4, whereas V-PROLI/NO was metabolized mainly by CYP1A2. Importantly, V-PYRRO/NO was a better NO releaser in vivo and in the isolated, perfused liver than V-PROLI/NO, an effect compatible with the superior antisteatotic activity of V-PYRRO/NO. In conclusion, V-PYRRO/NO displayed a pronounced antisteatotic effect associated with liver-targeted NO release, whereas V-PROLI/NO showed low effectiveness, was not taken up by the liver, and was eliminated mostly in unchanged form by the kidney. U.S. Government work not protected by

Impact of grape pomace consumption on the blood lipid profile and liver genes associated with lipid metabolism of young rats.

Science.gov (United States)

Yu, Jianmei; Bansode, Rishipal R; Smith, Ivy N; Hurley, Steven L

2017-08-01

Herein, we investigated the effects of grape pomace (GP) in diet on body weight, blood lipid profile, and expression of liver genes associated with lipid metabolism using a young rat model. In this study, twenty female Sprague-Dawley rats at 7 weeks of age were randomly divided into 4 groups, which were fed modified AIN-93G diets containing 0% (control), 6.9%, 13.8%, and 20.7% of GP for 10 weeks. Feed consumption and body weight were weekly determined. Blood samples were obtained at the beginning and end of the feeding period for cholesterol, alanine aminotransferase (ALT), and glucose analysis. At the end of the feeding period, all rats were fasted overnight and euthanized. Heart, kidney, and liver samples were obtained and weighed. Liver tissues were used for gene expression analysis. GP-containing diet did not influence the body weight of the rats. As GP content increased, blood triglyceride and very low density lipoprotein (VLDL) decreased (P consumption of a diet containing appropriate amount of GP may help in the reduction of body fat accumulation and prevention of obesity. This is the first study revealing the change in gene expression caused by long-term consumption of GP-containing diet.

Subchronic effects of valproic acid on gene expression profiles for lipid metabolism in mouse liver

International Nuclear Information System (INIS)

Lee, Min-Ho; Kim, Mingoo; Lee, Byung-Hoon; Kim, Ju-Han; Kang, Kyung-Sun; Kim, Hyung-Lae; Yoon, Byung-Il; Chung, Heekyoung; Kong, Gu; Lee, Mi-Ock

2008-01-01

Valproic acid (VPA) is used clinically to treat epilepsy, however it induces hepatotoxicity such as microvesicular steatosis. Acute hepatotoxicity of VPA has been well documented by biochemical studies and microarray analysis, but little is known about the chronic effects of VPA in the liver. In the present investigation, we profiled gene expression patterns in the mouse liver after subchronic treatment with VPA. VPA was administered orally at a dose of 100 mg/kg/day or 500 mg/kg/day to ICR mice, and the livers were obtained after 1, 2, or 4 weeks. The activities of serum liver enzymes did not change, whereas triglyceride concentration increased significantly. Microarray analysis revealed that 1325 genes of a set of 32,996 individual genes were VPA responsive when examined by two-way ANOVA (P 1.5). Consistent with our previous results obtained using an acute VPA exposure model (Lee et al., Toxicol Appl Pharmacol. 220:45-59, 2007), the most significantly over-represented biological terms for these genes included lipid, fatty acid, and steroid metabolism. Biological pathway analysis suggests that the genes responsible for increased biosynthesis of cholesterol and triglyceride, and for decreased fatty acid β-oxidation contribute to the abnormalities in lipid metabolism induced by subchronic VPA treatment. A comparison of the VPA-responsive genes in the acute and subchronic models extracted 15 commonly altered genes, such as Cyp4a14 and Adpn, which may have predictive power to distinguish the mode of action of hepatotoxicants. Our data provide a better understanding of the molecular mechanisms of VPA-induced hepatotoxicity and useful information to predict steatogenic hepatotoxicity

Sphingosine kinase/sphingosine 1-phosphate (S1P)/S1P receptor axis is involved in liver fibrosis-associated angiogenesis.

Science.gov (United States)

Yang, Le; Yue, Shi; Yang, Lin; Liu, Xin; Han, Zhen; Zhang, Yuanyuan; Li, Liying

2013-07-01

Sphingosine kinase (SphK)/sphingosine 1-phosphate (S1P)/S1P receptor (S1PR) axis is involved in multiple biological processes, including liver fibrosis. Angiogenesis is an important pathophysiological process closely associated with liver fibrosis; however, the functional role of SphK/S1P/S1PR in this process remains incompletely defined. Bile duct ligation or carbon tetrachloride was used to induce liver fibrosis in mice. Human fibrotic samples were obtained from livers of patients undergoing liver transplantation. S1P levels in the liver were examined by HPLC. Expression of angiogenic markers, including angiopoietin 1, CD31, vascular cell adhesion molecule-1, and von Willebrand factor, was characterized by immunofluorescence, real-time RT-PCR, and Western blot in the fibrotic liver and primary mouse hepatic stellate cells (HSCs). SphK inhibitor (SKI) or S1PR antagonists were administered intraperitoneally in mice. S1P levels in the liver were closely correlated with mRNA expression of angiogenic markers. Ang1 is expressed in activated HSCs of the fibrotic liver and in primary HSCs. In HSCs, by using specific antagonists or siRNAs, we demonstrated S1P stimulation induced Ang1 expression via S1PR1 and S1PR3. In vivo, S1P reduction by SKI inhibited angiogenesis in fibrotic mice. Furthermore, S1PR1/3 antagonist significantly blocked upregulation of angiogenic markers in the injured liver, and attenuated the extent of liver fibrosis, while S1PR2 antagonist had no effect on angiogenesis, supporting the key role of S1PR1 and S1PR3 in angiogenesis underlying liver fibrosis process. SphK1/S1P/S1PR1/3 axis plays a crucial role in the angiogenic process required for fibrosis development, which may represent an effective therapeutic strategy for liver fibrosis. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Thermal manipulation during embryogenesis has long-term effects on muscle and liver metabolism in fast-growing chickens.

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Thomas Loyau

Full Text Available Fast-growing chickens have a limited ability to tolerate high temperatures. Thermal manipulation during embryogenesis (TM has previously been shown to lower chicken body temperature (Tb at hatching and to improve thermotolerance until market age, possibly resulting from changes in metabolic regulation. The aim of this study was to evaluate the long-term effects of TM (12 h/d, 39.5°C, 65% RH from d 7 to 16 of embryogenesis vs. 37.8°C, 56% RH continuously and of a subsequent heat challenge (32°C for 5 h at 34 d on the mRNA expression of metabolic genes and cell signaling in the Pectoralis major muscle and the liver. Gene expression was analyzed by RT-qPCR in 8 chickens per treatment, characterized by low Tb in the TM groups and high Tb in the control groups. Data were analyzed using the general linear model of SAS considering TM and heat challenge within TM as main effects. TM had significant long-term effects on thyroid hormone metabolism by decreasing the muscle mRNA expression of deiodinase DIO3. Under standard rearing conditions, the expression of several genes involved in the regulation of energy metabolism, such as transcription factor PGC-1α, was affected by TM in the muscle, whereas for other genes regulating mitochondrial function and muscle growth, TM seemed to mitigate the decrease induced by the heat challenge. TM increased DIO2 mRNA expression in the liver (only at 21°C and reduced the citrate synthase activity involved in the Krebs cycle. The phosphorylation level of p38 Mitogen-activated-protein kinase regulating the cell stress response was higher in the muscle of TM groups compared to controls. In conclusion, markers of energy utilization and growth were either changed by TM in the Pectoralis major muscle and the liver by thermal manipulation during incubation as a possible long-term adaptation limiting energy metabolism, or mitigated during heat challenge.

The Metabolic Effects of Traditional Chinese Medication Qiliqiangxin on H9C2 Cardiomyocytes

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Shenghui Lin

2015-11-01

Full Text Available Background/Aims: A traditional Chinese medicine, Qiliqiangxin (QLQX has been identified to perform protective effects on myocardium energy metabolism in mice with acute myocardial infarction, though the effects of QLQX on myocardial mitochondrial biogenesis under physiological condition is still largely elusive. Methods: H9C2 cells were treated with different concentrations of QLQX (0.25, 0.5, and 1.0 µg/mL from 6 to 48 hours. Oxidative metabolism and glycolysis were measured by oxygen consumption and extracellular acidification with XF96 analyzer (SeaHorse. Mitochondrial content and ultrastructure were assessed by Mitotracker staining, confocal microscopy, flow cytometry, and transmission electron microscopy. Mitochondrial biogenesis-related genes were measured by qRT-PCR and Western blot. Results: H9C2 cells treated with QLQX exhibited increased glycolysis at earlier time points (6, 12, and 24 hours, while QLQX could enhance oxidative metabolism and mitochondrial uncoupling in H9C2 cells with longer duration of treatment (48 hours. QLQX also increased mitochondrial content and mitochondrial biogenesis-related gene expression levels, including 16sRNA, SSBP1, TWINKLE, TOP1MT and PLOG, with an activation of peroxisome proliferator-activated receptor coactivator 1 alpha (PGC-1α and its downstream effectors. Silencing PGC-1α could abolish the increased mitochondrial content in H9C2 cells treated with QLQX. Conclusion: Our study is the first to document enhanced metabolism in cardiomyocytes treated with QLQX, which is linked to increased mitochondrial content and mitochondrial biogenesis via activation of PGC-1α.

Effect of vitamin E in nonalcoholic fatty liver disease with metabolic syndrome: A propensity score-matched cohort study

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Gi Hyun Kim

2015-12-01

Full Text Available Background/AimsVitamin E improves the biochemical profiles and liver histology in nonalcoholic steatohepatitis, but the role of vitamin E is not clearly defined in the management of nonalcoholic fatty liver disease (NAFLD which includes both simple steatosis and steatohepatitis. Co-morbid metabolic syndrome increases the probability of steatohepatitis in NAFLD. In this study, we aimed to determine the short-term effects of vitamin E and off-treatment durability of response in a propensity-score matched cohort of NAFLD patients with metabolic syndrome.MethodsA retrospective cohort was constructed by retrieving 526 consecutive NAFLD patients from the electronic medical record data warehouse of a tertiary referral hospital in South Korea. Among them, 335 patients (63.7% had metabolic syndrome and were eligible for vitamin E therapy. In order to assess the effect of vitamin E, propensity score matching was used by matching covariates between control patients (n=250 and patients who received vitamin E (n=85.ResultsThe PS-matched vitamin E group (n=58 and control group (n=58 exhibited similar baseline metabolic profiles. After 6 months of vitamin E therapy, the mean ALT levels decreased significantly compared to PS-matched control (P<0.01. The changes in metabolic profiles (body weight, lipid and glucose levels did not differ between control and vitamin E groups during the study period.ConclusionsShort-term vitamin E treatment significantly reduces ALT levels in NAFLD patients with metabolic syndrome, but metabolic profiles are not affected by vitamin E.