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Sample records for rat liver dihydrodiol

  1. Radiochemical detection of dihydrodiol dehydrogenase: distribution of the indomethacin sensitive enzyme in rat tissues

    SciTech Connect

    Ivins, J.; Penning, T.

    1986-05-01

    Dihydrodiol dehydrogenase catalyzes the NADP/sup +/ dependent oxidation of trans-dihydrodiols of polycyclic aromatic hydrocarbons (PAH) which are potent proximate carcinogens. The authors have developed a highly sensitive radiochemical assay for this enzyme in which the oxidation of trans-1,2-dihydroxy-3,5-cyclohexadiene, a model substrate for trans-dihydrodiol proximate carcinogens, is coupled to O-methylation catalyzed by catechol O-methyl transferase. Using S-adenosyl-(/sup 3/H-methyl)-methionine as methyl donor at a specific activity of 0.1 nCi/pmol and extracting the product, /sup 3/H-o-methoxyphenol, the assay provides a 5000 fold increase in sensitivity over the existing spectrophotometric method. The radiochemical assay was validated by comparing the K/sub m/ and V/sub max/ values for rat liver cytosol with those derived spectrophotometrically. In both instances there was close agreement between values (K/sub m/ = 0.77 +/- 0.11 mM and V/sub max/ = 2.14 +/- 0.13 nmoles/min/mg protein determined radiochemically; K/sub m/ = 0.96 +/- 0.10 mM and V/sub max/ = 6.31 +/- 0.50 nmoles/min/mg protein determined spectrophotometrically). Using the radiochemical method, dihydrodiol dehydrogenase activity was detected in the following rat tissues: liver > lung > heart > small intestine > testis > seminal vesicle > bladder > prostate > spleen. Specific activities ranged between 0.944 and 0.016 nmoles/min/mg protein. In liver, lung, and testis, which are sites of PAH metabolism, the dehydrogenase is sensitive to inhibition by low ..mu..M concentrations of indomethacin, suggesting that this drug can prevent the detoxification of proximate carcinogens by this route.

  2. Activity of rat UGT1A1 towards benzo[a]pyrene phenols and dihydrodiols.

    PubMed

    Webb, Laura; Miles, Kristini; Kessler, Fay; Ritter, Joseph K

    2006-05-01

    Four UDP-glucuronosyltransferases from the rat UGT1A family were tested for activity towards benzo[a]pyrene phenols and dihydrodiols. UGT1A1 and UGT1A7 were found to be broadly active towards BaP metabolites. Antisera recognizing rat UGT1A1 and UGT1A7 were used to assess UGT levels in relation to UGT activity towards benzo[a]pyrene-7,8-dihydrodiol (BPD). The rank BPD UGT activities were liver=intestine≫kidney, whereas UGT1A1 was highest in liver and UGT1A7 was highest in intestine. Phenobarbital, an inducer of hepatic UGT1A1, only slightly increased BPD UGT activity, whereas UGT1A7 inducers more potently increased the activity. Inhibition studies using the differential UGT1A1 inhibitor, bilirubin, suggest that UGT1A1 is not a major contributor to the constitutive BPD glucuronidating activity of control rat liver microsomes. These data suggest that multiple UGT1A enzymes contribute to glucuronidation of BPD and other BaP metabolites, and that their relative contributions depend on tissue- and environmental-specific factors. PMID:21783661

  3. Dihydrodiol dehydrogenase and polycyclic aromatic hydrocarbon metabolism

    SciTech Connect

    Smithgall, T.E.

    1986-01-01

    Carcinogenic activation of polycyclic aromatic hydrocarbons by microsomal monoxygenases proceeds through trans-dihydrodiol metabolites to diol-epoxide ultimate carcinogens. This thesis directly investigated the role of dihydrodiol dehydrogenase, a cytosolic NAD(P)-linked oxidoreductase, in the detoxification of polycyclic aromatic trans-dihydrodiols. A wide variety of non-K-region trans-dihydrodiols were synthesized and shown to be substrates for the homogeneous rat liver dehydrogenase, including several potent proximate carcinogens derived from 7,12-dimethylbenz(a)anthracene, 5-methylchrysene, and benzo(a)pyrene. Since microsomal activation of polycyclic aromatic hydrocarbons is highly stereospecific, the stereochemical course of enzymatic trans-dihydrodiol oxidation was monitored using circular dichroism spectropolarimetry. The major product formed from the dehydrogenase-catalyzed oxidation of the trans-1,2-dihydrodiol of naphthalene was characterized using UV, IR, NMR, and mass spectroscopy, and appears to be 4-hydroxy-1,2-naphthoquinone. Mass spectral analysis suggests that an analogous hydroxylated o-quinone is formed as the major product of benzo(a)pyrene-7,8-dihydrodiol oxidation. Enzymatic oxidation of trans-dihydrodiols was shown to be potently inhibited by all of the major classes of the nonsteroidal antiinflammatory drugs. Enhancement of trans-dihydrodiol proximate carcinogen oxidation may protect against possible adverse effects of the aspirin-like drugs, and help maintain the balance between activation and detoxification of polycyclic aromatic hydrocarbons.

  4. Metabolic conversion of dibenz(a,h)anthracene (+/-)trans-1,2-dihydrodiol and chrysene (+/-)trans-3,4-dihydrodiol to vicinal dihydrodiol epoxides

    SciTech Connect

    Chou, M.W.; Fu, P.P.; Yang, S.K.

    1981-07-01

    The hydroxyl groups of dibenz(z,h)anthracene trans-1,2-dihydrodiol and chrysene trans-3,4-dihydrodiol are known to be predominantly in quasi-axial conformations. These dihydrodiols were metabolized by liver microsomes from 3-methylcholanthrene-pretreated rats to form 1,2,3,4-tetrahydrotetrols as the major products. The major metabolites of the dihydrodiols were isolated by reversed-phase high-performance liquid chromatography and identified by ultraviolet-visible absorption and mass spectral analyses. The results indicate that axial hydroxyl groups of dibenz(a,h)anthracene trans-1,2-dihydrodiol and of chrysene trans-3,4-dihydrodiol do not direct metabolism away from their respective vicinal double bond.

  5. Regio- and stereospecificity of 3. cap alpha. -hydroxysteroid/dihydrodiol dehydrogenase for trans-dihydrodiols of polycyclic aromatic hydrocarbons

    SciTech Connect

    Smithgall, T.E.; Harvey, R.G.; Penning, T.M.

    1986-03-01

    Homogeneous 3..cap alpha..-hydroxysteroid/dihydridiol dehydrogenase of rat liver cytosol catalyzes the NAD(P)-dependent oxidation of a variety of trans-dihydrodiols of aromatic hydrocarbons. V/sub max//K/sub m/ ratios indicate that benzenedihydrodiol and the trans-1,2- and trans-7,8-dihydrodiols of 5-methylchrysene are most efficiently oxidized, followed by the trans-7,8-dihydrodiol of benzo(a)pyrene. The enzyme displays rigid regio-selectivity, since it readily oxidizes non-K-region trans-dihydrodiols but not the corresponding K-region isomers. Using circular dichroism spectrometry the stereochemical course of the reaction was monitored. The dehydrogenase preferentially oxidizes the (+)-(1S,2S)-diols of benzene, naphthalene, phenanthrene, and chrysene. Apparent inversion of this preference occurs with the trans-7,8-dihydrodiol of 5-methylchrysene, as the (-)-enantiomer is utilized. No change in the sign of the Cotton Effect is observed following oxidation of the (+/-)-trans-7,8-dihydrodiol of benzo(a)pyrene. Incubation of the (/sup 3/H)-(+/-)-trans-7,8-dihydrodiol of benzo(a)pyrene with the purified dehydrogenase results in greater than 90% utilization of the potent proximate carcinogen, suggesting that both the (-)-(7R,8R)- and (+)-(7S,8S)-isomers are utilized. These data show that the dehydrogenase displays the appropriate regio-and stereospecificity to oxidized both the major and minor non-K-region trans-dihydrodiols that arise from the microsomal metabolism of benzo(a)pyrene in vivo.

  6. Cloning, sequencing, and functional analysis of the 5'-flanking region of the rat 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase gene.

    PubMed

    Lin, H K; Penning, T M

    1995-09-15

    Rat liver 3 alpha-hydroxysteroid/dihydrodiol dehydrogenase (3 alpha-HSD/DD) is a member of the aldo-keto reductase gene superfamily. It displays high constitutive expression and inactivates circulating steroid hormones and suppresses the formation of polycyclic aromatic hydrocarbon anti- and syn-diol-epoxides (ultimate carcinogens). To elucidate mechanisms responsible for constitutive expression of the 3 alpha-HSD/DD gene a rat genomic library obtained from adult Sprague-Dawley female liver (HaeIII partial digest) was screened, using a probe corresponding to the 5'-end of the cDNA (-15 to +250), and a 15.8-kb genomic clone was isolated. Sequencing revealed that 6.3 kb contained exon 1 (+16 to +138 bp) plus additional introns and exons. The transcription start site (+1) was located by primer extension analysis, and the initiation codon, ATG, was located at +55 bp. The remaining 9.5 kb represented the 5'-flanking region of the rat 3 alpha-HSD/DD gene. A 1.6-kb fragment of this region was sequenced. A TATTTAA sequence (TATA box) was found at 33 bp upstream from the major transcription start site. cis-acting elements responsible for the constitutive expression of the rat 3 alpha-HSD/DD gene were located on the 5'-flanking region by transient transfection of reporter-gene (chloramphenicol acetyl transferase, CAT) constructs into human hepatoma cells (HepG2). CAT assays identified the basal promoter between (-199 and +55 bp), the presence of a proximal enhancer (-498 to -199 bp) which stimulated CAT activity 6-fold, the existence of a powerful silencer (-755 to -498 bp), and a strong distal enhancer (-4.0 to -2.0 kb) which increased CAT activity by 20-40-fold. A computer search of available consensus sequences for trans-acting factors revealed that a cluster of Oct-sites were uniquely located in the silencer region. Using the negative response element (-797 to -498 bp) as a probe and nuclear extracts from HepG2 cells, three bands were identified by gel mobility shift

  7. Spectroscopic identification of 0-quinones as the products of polycyclic aromatic trans-dihydrodiol oxidation catalyzed by dihydrodiol dehydrogenase

    SciTech Connect

    Smithgall, T.; Penning, T.

    1987-05-01

    Dihydrodiol dehydrogenase catalyzes the NADP-dependent oxidation of polycyclic aromatic trans-dihydrodiols, a reaction that may suppress their carcinogenicity provided the products of the reaction are non-carcinogenic. Oxidation of the trans-1,2-dihydrodiol of naphthalene (NP-diol) or the 7,8-dihydrodiol of benzo(a)pyrene (BP-diol) by the homogeneous rat liver dehydrogenase resulted in the formation of multiple products by TLC, and none of these co-migrated with the corresponding 0-quinones standards. In subsequent reactions, the 0-quinones were trapped by conducting the oxidation of either NP-diol or BP-diol in phosphate buffer containing mercaptoethanol. The products of these reactions were identified by 500 Mhz NMR and electron impact mass spectrometry as mercaptoethanol adducts of the 1,2-quinone of naphthalene (m/e M+=234) and the 7,8-quinone of benzo(a)pyrene (m/e M+=358). The 7,8-quinone of benzo(a)pyrene also reacted with glutathione and cysteine to form water-soluble metabolites, but did not react with adenosine or guanosine.

  8. Toxicological significance of dihydrodiol metabolites

    SciTech Connect

    Hsia, M.T.

    1982-01-01

    Dihydrodiols are often found as the major organic-extractable metabolites of various olefinic or aromatic xenobiotics in many biological samples. Studies on the chemistry of dihydrodiol metabolites have provided insight into the pharmacokinetic behavior and the mode of action of the parent compound. The toxicology of dihydrodiol is more complex than what can be deduced solely on the basis of diminished bioavailability of the epoxide precursor, and the increased hydrophilicity associated with the dihydrodiol moiety. Dihydrodiols can be intrinsically toxic and may even represent metabolically activated species. Some of the dihydrodiol metabolites may still retain sufficient lipophilic character to serve again as substrates for microsomal oxygenases. Because of the tremendous chemical and biological diversity that existed among the various dihydrodiols, more mechanistic studies are needed to examine the toxicological properties of these compounds. It may be premature to conclude dihydrodiol formation as purely a detoxification route for xenobioties.

  9. Metabolism of benzo(c)chrysene by rat liver enzymes

    SciTech Connect

    Chadha, A.; Miyata, N.; Levin, W.; Jerina, D.M.

    1987-05-01

    Metabolism of the weak carcinogen benzo(c)chrysene by microsomes and by a purified system reconstituted with cytochrome P-450c and epoxide hydrolase has been examined. With microsomes from 3-methylcholanthrene-treated rats, the hydrocarbon is metabolized at a rate of 6.9 nmoles/min/nmole of cytochrome P-450 as compared to 0.86 for control and 0.65 for phenobarbital-treated rats. Dihydrodiols are the major metabolites, accounting for 50-70% of the total metabolism. The K-region 7,8-dihydrodiol is the principal metabolite while the benzo-ring 1,2- and 9,10 dihydrodiols, precursors to potentially tumorigenic bay-region epoxides are formed in much smaller amounts. The bay-region 3,4-dihydrodiol accounts for 10% of the total metabolites, except in the case of the reconstituted system. The K-region 7,8-dihydrodiol and the benzo-ring 1,2- and 9,10-dihydrodiols are formed with highest enantiomeric purity by microsomes from 3-methylcholanthrene-treated rats. In the case of the K-region dihydrodiol, the (7S,8S)-enantiomer predominates, however in the benzo-ring dihydrodiols it is the (R,R)-enantiomer which predominates in all three microsomal preparations. Phenols at the 3-, 4- and 9-positions account for the balance of the metabolites.

  10. Synthesis of fjord region tetraols and their use in hepatic biotransformation studies of dihydrodiols of benzo[c]chrysene, benzo[g]chrysene and dibenzo[a,l]pyrene.

    PubMed

    Luch, A; Platt, K L; Seidel, A

    1998-04-01

    Metabolic activation of the racemic benzo[c]chrysene-trans-9,10-, benzo[g]chrysene-trans-11,12- and dibenzo[a,l]pyrene-trans-11,12-dihydrodiols to fjord region syn- and anti-dihydrodiol epoxides by microsomes of Aroclor 1254-treated Sprague-Dawley rats has been examined. Since the fjord region dihydrodiol epoxides were hydrolytically unstable under the experimental conditions, their enzymatic formation was determined by analyzing the tetraols as their products of acidic hydrolysis upon addition of perchloric acid. The various stereoisomeric tetraols formed were separated by HPLC and identified by co-chromatography with authentic tetraols, which had been prepared by acidic hydrolysis of synthetically available syn- and anti-dihydrodiol epoxides and characterized by NMR and UV spectroscopy. Under standardized conditions the acidic hydrolysis of syn-dihydrodiol epoxides of benzo[c]chrysene, benzo[g]chrysene and dibenzo[a,l]pyrene resulted in the formation of two tetraols with cis/trans ratios of 81:19, 77:23 and 80:20, respectively, whereas the anti-dihydrodiol epoxides underwent almost exclusively trans hydrolysis. The proportion of the stereoisomeric tetraols obtained from microsomal incubations indicates that all three dihydrodiols are predominantly oxidized at the adjacent olefinic double bond to the anti-diastereomers of the corresponding fjord region dihydrodiol epoxides accounting for 4-35% of the ethyl acetate-extractable metabolites. To allow quantitative assessment of the metabolites 3H-labeled trans-dihydrodiols were synthesized by reduction of the corresponding o-quinones with sodium borotritide. Metabolic conversion of benzo[c]chrysene-trans-9,10- and dibenzo[a,l]pyrene-trans-11,12-dihydrodiol by rat liver microsomes were in a similar low range during the first 10 min of incubation (6.2 +/- 1.2 and 3.4 +/- 1.0 nmol substrate/nmol cytochrome P450/10 min, respectively), whereas the conversion of benzo[g]chrysene-trans-11,12-dihydrodiol was much higher (20

  11. Metabolism of phenanthrene by brown bullhead liver microsomes.

    PubMed

    Pangrekar, Jyotsna; Kole, Panna L; Honey, Sangeet A; Kumar, Subodh; Sikka, Harish C

    2003-09-10

    We have investigated the regio- and stereoselective metabolism of phenanthrene by the liver microsomes of brown bullhead (Ameriurus nebulosus), a bottom dwelling fish species. The liver microsomes from untreated and 3-methylcholanthrene (3-MC)-treated brown bullheads metabolized phenanthrene at a rate of 14.1 and 20.7 pmol/mg protein/min, respectively, indicating that the hydrocarbon is a rather poor substrate for bullhead liver microsomes contrary to what has been reported for rat liver microsomes. The major phenanthrene metabolites formed by liver microsomes from untreated and 3-MC-treated bullheads included benzo-ring 1,2-dihydrodiol (25.3 and 11.6%), K-region 9,10-dihydrodiol (9.6 and 9.6%), and phenols (40.5 and 54.5%). The 3,4-dihydrodiol represented a minor proportion of the total phenanthrene metabolites. The low proportion of the 9,10-dihydrodiol formed by both control and 3-MC-treated bullhead microsomes sharply contrasts the previous data reported for the corresponding rat liver microsomes which metabolized phenanthrene predominantly to its 9,10-dihydrodiol representing 76.6 and 67.1%, respectively of the total metabolites. Liver microsomes from 3-MC-treated bullheads, like rat liver microsomes, were more selective in their attack at the 1,2-position of the benzo-ring than at the 3,4-position of the benzo-ring. Phenanthrene 1,2-dihydrodiol and 3,4-dihydrodiol formed by liver microsomes from both control and 3-MC-treated bullheads consisted predominantly of their R,R enantiomer. Phenanthrene, compared with benzo[a]pyrene and chrysene, is metabolized by bullhead liver microsomal enzymes to its benzo-ring dihydrodiols with a relatively low degree of stereoselectivity.

  12. Stereoselective fungal metabolism of 7,12-dimethylbenz(a)anthracene: identification and enantiomeric resolution of a K-region dihydrodiol

    SciTech Connect

    McMillan, D.C.; Fu, P.P.; Cerniglia, C.E.

    1987-10-01

    Syncephalastrum racemosum UT-70 and Cunninghamella elegans ATCC 36112 metabolized 7,12-dimethylbenz(a)anthracene (7,12-DMBA) to hydroxymethyl metabolites as well as 7-hydroxymethyl-12-methylbenz(a)anthracene trans-3,4-, -5,6-, -8,9-, and -10,11-dihydrodiols. The 7,12-DMBA metabolites were isolated by reversed-phase high-performance liquid chromatography and identified by their UV-visible absorption, mass, and nuclear magnetic resonance spectral characteristics. A comparison of the circular dichroism spectra of the K-region (5,6-position) dihydrodiol of both fungal strains with those of the 7,12-DMBA 5S,6S-dihydrodiol formed from 7,12-DMBA by rat liver microsomes indicated that the major enantiomer of the 7-hydroxymethyl-12-methylbenz(a)anthracene trans-5,6-dihydrodiol formed by both fungal strains had a 5R,6R absolute stereochemistry. Direct resolution of the fungal trans-5,6-dihydrodiols by chiral stationary-phase high-performance liquid chromatography indicated that the ratios of the R,R and S,S, enantiomers were 88:12 and 77:23 for S. racemosum and C. elegans, respectively. These results indicate that the fungal metabolism of 7,12-DMBA at the K region (5,6-position) is highly stereoselective and different from that reported for mammalian enzyme systems.

  13. Stereoselective metabolism of chrysene by rat liver microsomes. Direct separation of diol enantiomers by chiral stationary phase h.p.l.c.

    PubMed

    Weems, H B; Fu, P P; Yang, S K

    1986-07-01

    The direct enantiomeric resolution of non-K region trans-1,2-dihydrodiol, 1,2,3,4-tetrahydro-trans-1,2-diol, trans-3,4-dihydrodiol and 1,2,3,4-tetrahydro-trans-3,4-diol, K region trans- and cis-5,6-dihydrodiols and their monomethyl ethers of chrysene was studied by chiral stationary phase high-performance liquid chromatography (CSP-h.p.l.c.). The chiral stationary phase columns were packed with gamma-aminopropylsilanized silica to which either (R)-N-(3,5-dinitrobenzoyl)-phenylglycine or (S)-N-(3,5-dinitrobenzoyl)leucine was bonded either ionically or covalently. Enantiomers of all dihydrodiol derivatives were resolved by one or more, but not all, of the chiral stationary phases utilized. Enantiomeric resolutions were substantially improved when the non-K region dihydrodiols were converted to tetrahydrodiols. The absolute configurations of the K region trans- and cis-5,6-dihydrodiols were established by the exciton chirality circular dichroism method. The (R,R):(S,S) enantiomer ratios, determined by CSP-h.p.l.c., of the 1,2-, 3,4- and 5,6-trans-dihydrodiols formed in the metabolism of chrysene by liver microsomes from untreated male rats of the Sprague--Dawley strain were found to be 51:49, 99:1 and 86:14, respectively; from phenobarbital-treated rats, 41:59, 99:1 and 87:13, respectively; from 3-methylcholanthrene-treated rats, 96:4, 99:1 and 92:8, respectively. The absolute configurations of chrysene 5,6-epoxide enantiomers, resolved by CSP-h.p.l.c., were elucidated by the determination of the structures and absolute configurations of their methoxylation products. Both enantiomers of chrysene 5,6-epoxide were hydrated by microsomal epoxide hydrolase to chrysene trans-5,6-dihydrodiol enriched (67-92%) in the 5R,6R enantiomer. Chrysene 5R,6S-epoxide was hydrated to trans-5,6-dihydrodiol at a rate approximately 6-fold faster than chrysene 5S,6R-epoxide.

  14. BIOTRANSFORMATION OF TRANS-4,5-DIHYDROXY-4,5-DIHYDROBENZO[A]PYRENE TO BENZO[A]PYRENE-BIS-DIOLS AND DNA ADDUCTS BY INDUCED RAT LIVER MICROSOMES

    EPA Science Inventory

    The biotransformation of (+)-trans-4,5-dihydroxy-4,5-dihydrobenzo[a]pyrene trans-B[a]P-4,5-diol), the K-region dihydrodiol of B[a]P, by B-naphthoflavone (BNF)-induced rat liver microsomes was studied. Trans-B[a]P-4,5-diol was metabolized to six major products as characterized by...

  15. Benzene toxicity: emphasis on cytosolic dihydrodiol dehydrogenases

    SciTech Connect

    Bolcsak, L.E.

    1982-01-01

    Blood dyscrasias such as leukopenia and anemia have been clearly identified as consequences of chronic benzene exposure. The metabolites, phenol, catechol, and hydroquinone produced inhibition of /sup 59/Fe uptake in mice which followed the same time course as that produced by benzene. The inhibitor of benzene oxidation, 3-amino-1,2,4-triazole, mitigated the inhibitory effects of benzene and phenol only. These data support the contention that benzene toxicity is mediated by a metabolite and suggest that the toxicity of phenol is a consequence of its metabolism to hydroquinone and that the route of metabolism to catechol may also contribute to the production of toxic metabolite(s). The properties of mouse liver cytosolic dihydrodiol dehydrogenases were examined. These enzymes catalyze the NADP/sup +/-dependent oxidation of trans-1,2-dihydro-1,2-dihydroxybenzene (BDD) to catechol, a possible toxic metabolite of benzene produced via this metabolic route. Four distinct dihydrodiol dehydrogenases (DD1, DD2, DD3, and DD4) were purified to apparent homogeneity as judged by SDS polyacrylamide gel electrophoresis and isoelectric focusing. DD1 appeared to be identical to the major ketone reductase and 17..beta..-hydroxysteroid dehydrogenase activity in the liver. DD2 exhibited aldehyde reductase activity. DD3 and DD4 oxidized 17..beta..-hydroxysteroids, but no carbonyl reductase activity was detected. These relationships between BDD dehydrogenases and carbonyl reductase and/or 17..beta..-hydroxysteroid dehydrogenase activities were supported by several lines of evidence.

  16. Regulation of human dihydrodiol dehydrogenase by Michael acceptor xenobiotics.

    PubMed

    Ciaccio, P J; Jaiswal, A K; Tew, K D

    1994-06-01

    A human oxidoreductase (H-37) that is overexpressed in ethacrynic acid-resistant HT29 colon cells (Ciaccio, P. J., Stuart, J.E., and Tew, K.D. (1993) Mol. Pharmacol. 43, 845-853) has been identified as a dihydrodiol dehydrogenase. Translated protein from a dihydrodiol dehydrogenase cDNA isolated from a library prepared from ethacrynic acid-resistant HT29 cell poly(A+) RNA was recognized by anti-H-37 IgG and was identical in molecular weight with H-37. The isolated cDNA was identical in both nucleotide and amino acid sequences with the recently cloned liver dihydrodiol dehydrogenase (Stolz, A., Hammond, L., Lou, H., Takikawa, H., Ronk, M., and Shively, J.E. (1993) J. Biol. Chem. 268, 10448-10457). Using this cDNA as probe, we have examined its induction by Michael acceptors. The steady state dihydrodiol dehydrogenase mRNA level in the ethacrynic acid-resistant line was increased 30-fold relative to that of wild-type cells. Twenty-four hour treatment of wild-type cells with ethacrynic acid or dimethyl maleate increased mRNA 10-fold and 5-fold, respectively. These changes are accompanied by both increased protein expression and increased NADP-dependent 1-acenaphthenol oxidative activity in cell cytosol. In gel shift assays, compared to wild type controls, increased binding of NAD(P)H quinone oxidoreductase human antioxidant response element (hARE) DNA to redox labile protein complexes present in treated and resistant cell nuclear extract was observed. Ethacrynic acid induced CAT activity 2-fold in Hepa1 cells stably transfected with NAD(P)H quinone oxidoreductase hARE-tk-CAT chimeric gene construct. Thus, dihydrodiol dehydrogenase protein is inducible by de novo synthesis from mRNA by structurally related monofunctional inducer Michael acceptors. Altered in vitro binding of nuclear protein to the hARE is indirect evidence for the involvement of an element similar to hARE in the regulation of dihydrodiol dehydrogenase by these agents. PMID:7515059

  17. Influence of gallic acid esters on drug-metabolizing enzymes of rat liver.

    PubMed

    Depner, M; Kahl, G F; Kahl, R

    1982-10-01

    The effect of three antioxidants, propyl, octyl and dodecyl gallate, on hepatic drug metabolism in male rats was studied in vivo and in vitro. When fed at a dietary concentration of 1% for 14 days, only dodecyl gallate increased relative liver weight. Cytochrome P-450 content was not influenced, but a slight increase in cytochrome b5 content was observed after the feeding of propyl gallate. Monooxygenase activity (benzo[a]pyrene-hydroxylase and ethoxycoumarin-deethylase activities) was not affected by propyl or octyl gallate, but a significant decrease in benzo[a]pyrene-hydroxylase activity was apparent in rats fed dodecyl gallate. Study of benzo[a]pyrene-metabolite formation in liver microsome preparations from control and propyl gallate-treated rats showed an overall decrease in metabolite production following gallate treatment, the decrease being statistically significant for the formation of the 9,10-dihydrodiol. Epoxide-hydratase activity was enhanced by a factor of 1.5 in rats fed propyl gallate; glutathione-transferase activity was unaffected. In vitro, the gallates proved to be potent inhibitors of ethoxycoumarin deethylation in liver microsomes from untreated and phenobarbital-treated rats; however, when cytochrome P-448 had been induced by pretreatment with 3-methylcholanthrene, ethoxycoumarin deethylase was less sensitive to the inhibitory action of the gallates.

  18. Isolating Lysosomes from Rat Liver.

    PubMed

    Pryor, Paul R

    2016-04-01

    This protocol describes the generation of a fraction enriched in lysosomes from rat liver. The lysosomes are rapidly isolated using density-gradient centrifugation with gradient media that retain the osmolarity of the lysosomes such that they are functional and can be used in in vitro assays.

  19. The stereochemistry of the major rat hepatic microsomal metabolites of 7,9-dimethylbenz[c]acridine and 7,10-dimethylbenz[c]acridine

    SciTech Connect

    Ye, Y.; Duke, C.C.; Holder, G.M.

    1995-03-01

    The monofunctionalized dihydrodiol metabolites of 7,9-dimethylbenz[c]acridine and 7,10-dimethylbenz[c]acridine formed in incubations with rat liver microsomes from untreated and phenobarbital and 3-methylcholanthrene-pretreated rats were isolated by reversed-phase high performance liquid chromatography. The relative amounts of each enantiomer were determined by HPLC of diasteroisomeric esters with (+)-(1R,2S,4S)-endo-1,4,5,6,7,7- hexachlorobicyclo-[2.2.1]hept-5ene-2-carboxylic acid (HCA). For the K-region dihydrodiols, absolute configurations were determined from their circular dichroic spectra using the empirical method. The absolute configuration of 3,4-dihydrodiol of 7,9-dimethylbenz[c]acridine was determined by the exciton chirality method from the CD spectrum of its bis-4-(dmethylamino)benzoate ester. For the 8,9-dihydrodiol of 7,10-dimethylbenz[c]acridine the absolute configurations were tentatively assigned by normal-phase HPLC comparison of the (+)-HCA esters with literature data. In every case the R,R-configuration predominated with optical purities >86% for non-K-region dihydrodiols and 56-68% for the K-region dihydrodiols. 38 refs., 5 figs., 2 tabs.

  20. Aspartate carbamoyltransferase from rat liver

    PubMed Central

    Bresnick, E.; Mossé, Helena

    1966-01-01

    1. Aspartate-carbamoyltransferase activity was concentrated from rat-liver preparations. Only l-aspartate, β-benzyl-l-aspartate and β-erythro-hydroxy-dl-aspartate were carbamoylated enzymically. The Km for l-aspartate and carbamoyl phosphate have been determined by three methods: colorimetric procedure, radioactive assay with [14C]aspartate and an assay with [14C]carbamoyl phosphate. 2. The Km for aspartate has been determined as a function of the pH; the pK of the functional group at the active site of the enzyme, pKe, was at pH9·0. Enzymic activity was diminished in the presence of N-ethylmaleimide, p-hydroxymercuribenzoate and the heavy metals Ag+, Hg2+, or Zn2+. The inhibitions could be prevented by mercaptoethanol. These findings suggested the association of a thiol group with the enzymic activity. 3. Enzymic activity was also decreased by sodium lauryl sulphate, urea and dioxan. Competitive inhibition (with l-aspartate) was manifested by maleate, succinate, oxaloacetate, β-erythro-hydroxy-dl-aspartate and β-benzyl-l-aspartate. The Ki for most of these inhibitions has been determined. 4. The properties of the liver enzyme are compared with those of Escherichia coli aspartate carbamoyltransferase and the implications of the findings are discussed. PMID:5339547

  1. Liver uptake of biguanides in rats.

    PubMed

    Sogame, Yoshihisa; Kitamura, Atsushi; Yabuki, Masashi; Komuro, Setsuko

    2011-09-01

    Metformin is an oral antihyperglycaemic agent widely used in the management of non-insulin-dependent diabetes mellitus. The liver is the primary target, metformin being taken up into human and rat hepatocytes via an active transport mechanism. The present study was designed to compare hepatic uptake of two biguanides, metformin and phenformin, in vitro and in vivo. In in vitro experiments, performed using rat cryopreserved hepatocytes, phenformin exhibited a much higher affinity and transport than metformin, with marked differences in kinetics. The K(m) values for metformin and phenformin were 404 and 5.17μM, respectively, with CLint (V(max)/K(m)) values 1.58μl/min per 10(6) cells and 34.7μl/min per 10(6) cells. In in vivo experiments, when (14)C-metformin and (14)C-phenformin were given orally to male rats at a dose of 50mg/kg, the liver concentrations of radioactivity at 0.5 hour after dosing were 21.5μg eq./g with metformin but 147.1μg eq./g for phenformin, ratios of liver to plasma concentrations being 4.2 and 61.3, respectively. In conclusion, the results suggest that uptake of biguanides by rat hepatocytes is in line with the liver distribution found in vivo, phenformin being more efficiently taken up by liver than metformin after oral administration.

  2. Methaqualone metabolism by rat liver microsomes.

    PubMed

    Manowitz, P; Shull, C M

    1976-01-01

    A rat hepatic microsomal system has been established which metabolizes methaqualone. The microsomes are obtained from livers of rats treated with phenobarbital. The methaqualone is dissolved in polyethylene glycol-200 prior to addition to the incubation mixture. A comparison is made between the metabolites obtained in this in vitro system and metabolites obtained from urines of phenobarbital treated rats injected with methaqualone. The same two and sometimes three metabolites, as determined by thin layer and gas liquid chromatography, were found in both the complete microsomal incubation system and the urines.

  3. Extensive exchange of rat liver microsomal phospholipids.

    PubMed

    Zilversmit, D B; Hughes, M E

    1977-08-15

    Liver microsomal fractions were prepared from rats injected with a single dose of choline [14C]methylchloride or with single or multiple doses of 32Pi. Exchangeability of microsomal phospholipids was determined by incubation with an excess of mitochondria and phospholipid exchange proteins derived from beef heart, beef liver or rat liver. Labeled phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylinositol were found to act as a single pool and were 85--95% exchangeable in 1--2h. High latencies of mannose-6-phosphate phosphohydrolase activities and impermeability of microsomes to EDTA proved that phospholipid exchange proteins did not have access to the intracisternal space. If microsomal membranes are largely composed of phospholipid bilayers, the experiments suggest that one or more of the phospholipid classes in microsomal membranes undergo rapid translocation between the inner and outer portions of the bilayer.

  4. Extensive exchange of rat liver microsomal phospholipids.

    PubMed

    Zilversmit, D B; Hughes, M E

    1977-08-15

    Liver microsomal fractions were prepared from rats injected with a single dose of choline [14C]methylchloride or with single or multiple doses of 32Pi. Exchangeability of microsomal phospholipids was determined by incubation with an excess of mitochondria and phospholipid exchange proteins derived from beef heart, beef liver or rat liver. Labeled phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidylinositol were found to act as a single pool and were 85--95% exchangeable in 1--2h. High latencies of mannose-6-phosphate phosphohydrolase activities and impermeability of microsomes to EDTA proved that phospholipid exchange proteins did not have access to the intracisternal space. If microsomal membranes are largely composed of phospholipid bilayers, the experiments suggest that one or more of the phospholipid classes in microsomal membranes undergo rapid translocation between the inner and outer portions of the bilayer. PMID:889827

  5. Stereoselective formations of K-region and non-K-region epoxides in the metabolism of chrysene by rat liver microsomal cytochrome P-450 isozymes.

    PubMed

    Yang, S K; Bao, Z P

    1987-07-01

    The K-region 5,6-epoxide and non-K-region 1,2- and 3,4-epoxides of chrysene were isolated by normal phase high performance liquid chromatography (HPLC) from a mixture of products formed in the metabolism of chrysene by liver microsomes from untreated (control), phenobarbital-treated, or 3-methylcholanthrene-treated rats in the presence of an epoxide hydrolase inhibitor, 3,3,3-trichloropropylene 1,2-oxide. Epoxides were characterized by ultraviolet, mass, and circular dichroism spectral and chiral stationary phase HPLC analyses. Each of the metabolically formed epoxides was hydrated by rat liver microsomal epoxide hydrolase to a trans-dihydrodiol. The metabolically formed chrysene 5,6-epoxides were determined by chiral stationary phase HPLC and were found to contain (5S,6R):(5R,6S) enantiomer ratios of 68:32 (control), 71:29 (phenobarbital), and 5:95 (3-methylcholanthrene), respectively. The enantiomers of chrysene 1,2-epoxide and 3,4-epoxide were also resolved by chiral stationary phase HPLC. However, the enantiomeric compositions of the metabolically formed chrysene 1,2- and 3,4-epoxides, which racemized rapidly at room temperature, could not be directly determined. By using molecular oxygen-18 in the in vitro incubation of chrysene and by mass spectral analyses of the resulting oxygen-18-containing dihydrodiol metabolites and their acid-catalyzed dehydration (phenolic) products, both 1,2-epoxide and 3,4-epoxide were found to be converted by microsomal epoxide hydrolase-catalyzed water attack at predominantly (greater than or equal to 97%) the allylic carbons.

  6. Rat liver endothelial and Kupffer cell-mediated mutagenicity and polycyclic aromatic hydrocarbons and aflatoxin B sub 1

    SciTech Connect

    Steinberg, P.; Schlemper, B.; Molitor, E.; Platt, K.L.; Seidel, A.; Oesch, F. )

    1990-08-01

    The ability of isolated rat liver endothelial and Kupffer cells to activate benzo(a)pyrene (BP), trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (DDBP), trans-1,2-dihydroxy-1,2-dihydrochrysene (DDCH), and aflatoxin B{sub 1} (AFB{sub 1}) to mutagenic metabolites was assessed by means of a cell-mediated bacterial mutagenicity assay and compared with the ability of parenchymal cells to activate these compounds. Endothelial and Kupffer cells from untreated rats were able to activate AFB{sub 1} and DDBP; DDBP was activated even in the absence of an NADPH-generating system. Pretreating the animals with Aroclor 1254 strongly enhanced the mutagenicity of the dihydrodiol, whereas the mutagenicity of AFB{sub 1} showed a slight increase. BP and DDCH were only activated by endothelial and Kupffer cells isolated from Aroclor 1254-pretreated rats. Parenchymal cells form untreated animals activated all four carcinogens tested; Aroclor 1254 enhanced the parenchymal cell-mediated mutagenicity of BP and DDCH but did not affect that of DDBP and clearly reduced that of AFB{sub 1}. The reduced mutagenicity of AFB{sub 1} correlates with the decrease in the amount of 2{alpha}-hydroxytestosterone formed when testosterone was incubated with parenchymal cell microsomes from Aroclor 1254-pretreated rats (compared with microsomes from untreated animals): the formation of 2{alpha}-hydroxytestosterone is specifically catalyzed by cytochrome P-450h, a hemoprotein thought to be involved in the activation of AFB{sub 1}. These results show that not only rat liver parenchymal cells, but also endothelial and Kupffer cells, activated several carcinogens to mutagenic metabolites.

  7. Generation and characterization of rat liver stem cell lines and their engraftment in a rat model of liver failure

    PubMed Central

    Kuijk, Ewart W.; Rasmussen, Shauna; Blokzijl, Francis; Huch, Meritxell; Gehart, Helmuth; Toonen, Pim; Begthel, Harry; Clevers, Hans; Geurts, Aron M.; Cuppen, Edwin

    2016-01-01

    The rat is an important model for liver regeneration. However, there is no in vitro culture system that can capture the massive proliferation that can be observed after partial hepatectomy in rats. We here describe the generation of rat liver stem cell lines. Rat liver stem cells, which grow as cystic organoids, were characterized by high expression of the stem cell marker Lgr5, by the expression of liver progenitor and duct markers, and by low expression of hepatocyte markers, oval cell markers, and stellate cell markers. Prolonged cultures of rat liver organoids depended on high levels of WNT-signalling and the inhibition of BMP-signaling. Upon transplantation of clonal lines to a Fah−/− Il2rg−/− rat model of liver failure, the rat liver stem cells engrafted into the host liver where they differentiated into areas with FAH and Albumin positive hepatocytes. Rat liver stem cell lines hold potential as consistent reliable cell sources for pharmacological, toxicological or metabolic studies. In addition, rat liver stem cell lines may contribute to the development of regenerative medicine in liver disease. To our knowledge, the here described liver stem cell lines represent the first organoid culture system in the rat. PMID:26915950

  8. An ethoxyquin-inducible aldehyde reductase from rat liver that metabolizes aflatoxin B1 defines a subfamily of aldo-keto reductases.

    PubMed

    Ellis, E M; Judah, D J; Neal, G E; Hayes, J D

    1993-11-01

    Protection of liver against the toxic and carcinogenic effects of aflatoxin B1 (AFB1) can be achieved through the induction of detoxification enzymes by chemoprotectors such as the phenolic antioxidant ethoxyquin. We have cloned and sequenced a cDNA encoding an aldehyde reductase (AFB1-AR), which is expressed in rat liver in response to dietary ethoxyquin. Expression of the cDNA in Escherichia coli and purification of the recombinant enzyme reveals that the protein exhibits aldehyde reductase activity and is capable of converting the protein-binding dialdehyde form of AFB1-dihydrodiol to the nonbinding dialcohol metabolite. We show that the mRNA encoding this enzyme is markedly elevated in the liver of rats fed an ethoxyquin-containing diet, correlating with acquisition of resistance to AFB1. AFB1-AR represents the only carcinogen-metabolizing aldehyde reductase identified to date that is induced by a chemoprotector. Alignment of the amino acid sequence of AFB1-AR with other known and putative aldehyde reductases shows that it defines a subfamily within the aldo-keto reductase superfamily. PMID:8234296

  9. Characterization of the rat developmental liver transcriptome.

    PubMed

    Chapple, Richard H; Tizioto, Polyana C; Wells, Kevin D; Givan, Scott A; Kim, JaeWoo; McKay, Stephanie D; Schnabel, Robert D; Taylor, Jeremy F

    2013-04-16

    Gene regulation and transcriptome studies have been enabled by the development of RNA-Seq applications for high-throughput sequencing platforms. Next generation sequencing is remarkably efficient and avoids many issues inherent in hybridization-based microarray methodologies including the exon-specific dependence of probe design. Biologically relevant transcripts including messenger and regulatory RNAs may now be quantified and annotated regardless of whether they have previously been observed. We used RNA-Seq to investigate global patterns of gene expression in early developing rat liver. Liver samples from timed-pregnant Lewis rats were collected at six fetal and neonatal stages [embryonic day (E)14, E16, E18, E20, postnatal day (P)1, P7], transcripts were sequenced using an Illumina HiSeq 2000, and data analysis was performed with the Tuxedo software suite. Genes and isoforms differing in abundance were queried for enrichment within functionally related gene groups using the Functional Annotation Tool of the DAVID Bioinformatics Database. While hematopoietic gene expression is initiated by E14, hepatocyte maturation is a gradual process involving clusters of genes responsible for response to nutrients and enzymes responsible for glycolysis and fatty acid catabolism. Following birth, a large cluster of differentially abundant genes was enriched for mitochondrial gene expression and cholesterol synthesis indicating that by 1 wk of age, the liver is engaged in lipid sensing and bile production. Clustering results for differentially abundant genes and isoforms were similar with the greatest difference for the E14/E16 comparison. Finally, a bioinformatic approach was used to annotate 1,307 novel liver transcripts assembled from sequences that aligned to intergenic regions of the rat genome.

  10. Nicotinamide nucleotide synthesis in regenerating rat liver

    PubMed Central

    Ferris, G. M.; Clark, J. B.

    1971-01-01

    1. The concentrations and total content of the nicotinamide nucleotides were measured in the livers of rats at various times after partial hepatectomy and laparotomy (sham hepatectomy) and correlated with other events in the regeneration process. 2. The NAD content and concentration in rat liver were relatively unaffected by laparotomy, but fell to a minimum, 25 and 33% below control values respectively, 24h after partial hepatectomy. NADP content and concentration were affected similarly by both laparotomy and partial hepatectomy, falling rapidly and remaining depressed for up to 48h. 3. The effect of injecting various doses of nicotinamide on the liver DNA and NAD 18h after partial hepatectomy was studied and revealed an inverse correlation between NAD content and DNA content. 4. Injections of nicotinamide at various times after partial hepatectomy revealed that the ability to synthesize NAD from nicotinamide was impaired during the first 12h, rose to a peak at 26h and fell again by 48h after partial hepatectomy. 5. The total liver activity of NAD pyrophosphorylase (EC 2.7.7.1) remained at or slightly above the initial value for 12h after partial hepatectomy and then rose continuously until 48h after operation. The activity of NMN pyrophosphorylase (EC 2.4.2.12) showed a similar pattern of change after partial hepatectomy, but was at no time greater than 5% of the activity of NAD pyrophosphorylase. 6. The results are discussed with reference to the control of NAD synthesis in rapidly dividing tissue. It is suggested that the availability of cofactors and substrates for NAD synthesis is more important as a controlling factor than the maximum enzyme activities. It is concluded that the low concentrations of nicotinamide nucleotides in rapidly dividing tissues are the result of competition between NAD synthesis and nucleic acid synthesis for common precursor and cofactors. PMID:4398891

  11. Native structure of rat liver immune proteasomes.

    PubMed

    Stepanova, A A; Lyupina, Yu V; Sharova, N P; Erokhov, P A

    2016-05-01

    Native structure of active forms of rat liver immune proteasomes has been studied by two-dimensional electrophoresis method modified for analysis of unpurified protein fractions. The developed method allowed revealing the proteasome immune subunits LMP7 and LMP2 in 20S subparticles and in the structures bound to one or two PA28αβ activators, but not to the PA700 activator, which is involved in the hydrolysis of ubiquitinated proteins. The results obtained indicate the participation of the immune proteasomes in delicate regulatory mechanisms based on the production of biologically active peptides and exclude their participation in processes of crude degradation of "rotated" ubiquitinated proteins. PMID:27417720

  12. Multiphoton spectral analysis of benzo[a]pyrene uptake and metabolism in a rat liver cell line

    SciTech Connect

    Barhoumi, Rola; Mouneimne, Youssef; Ramos, Ernesto; Morisseau, Christophe; Hammock, Bruce D.; Safe, Stephen; Parrish, Alan R.; Burghardt, Robert C.

    2011-05-15

    Dynamic analysis of the uptake and metabolism of polycyclic aromatic hydrocarbons (PAHs) and their metabolites within live cells in real time has the potential to provide novel insights into genotoxic and non-genotoxic mechanisms of cellular injury caused by PAHs. The present work, combining the use of metabolite spectra generated from metabolite standards using multiphoton spectral analysis and an 'advanced unmixing process', identifies and quantifies the uptake, partitioning, and metabolite formation of one of the most important PAHs (benzo[a]pyrene, BaP) in viable cultured rat liver cells over a period of 24 h. The application of the advanced unmixing process resulted in the simultaneous identification of 8 metabolites in live cells at any single time. The accuracy of this unmixing process was verified using specific microsomal epoxide hydrolase inhibitors, glucuronidation and sulfation inhibitors as well as several mixtures of metabolite standards. Our findings prove that the two-photon microscopy imaging surpasses the conventional fluorescence imaging techniques and the unmixing process is a mathematical technique that seems applicable to the analysis of BaP metabolites in living cells especially for analysis of changes of the ultimate carcinogen benzo[a]pyrene-r-7,t-8-dihydrodiol-t-9,10-epoxide. Therefore, the combination of the two-photon acquisition with the unmixing process should provide important insights into the cellular and molecular mechanisms by which BaP and other PAHs alter cellular homeostasis.

  13. Ideal Experimental Rat Models for Liver Diseases

    PubMed Central

    Lee, Sang Woo; Kim, Sung Hoon; Min, Seon Ok

    2011-01-01

    There are many limitations for conducting liver disease research in human beings due to the high cost and potential ethical issues. For this reason, conducting a study that is difficult to perform in humans using appropriate animal models, can be beneficial in ascertaining the pathological physiology, and in developing new treatment modalities. However, it is difficult to determine the appropriate animal model which is suitable for research purposes, since every patient has different and diverse clinical symptoms, adverse reactions, and complications due to the pathological physiology. Also, it is not easy to reproduce identically various clinical situations in animal models. Recently, the Guide for the Care and Use of Laboratory Animals has tightened up the regulations, and therefore it is advisable to select the appropriate animals and decide upon the appropriate quantities through scientific and systemic considerations before conducting animal testing. Therefore, in this review article the authors examined various white rat animal testing models and determined the appropriate usable rat model, and the pros and cons of its application in liver disease research. The authors believe that this review will be beneficial in selecting proper laboratory animals for research purposes. PMID:26421020

  14. Mutagenicity of comfrey (Symphytum Officinale) in rat liver.

    PubMed

    Mei, N; Guo, L; Fu, P P; Heflich, R H; Chen, T

    2005-03-14

    Comfrey is a rat liver toxin and carcinogen that has been used as a vegetable and herbal remedy by humans. In order to evaluate the mechanisms underlying its carcinogenicity, we examined the mutagenicity of comfrey in the transgenic Big Blue rat model. Our results indicate that comfrey is mutagenic in rat liver and the types of mutations induced by comfrey suggest that its tumorigenicity results from the genotoxicity of pyrrolizidine alkaloids in the plant. PMID:15726100

  15. Activation and metabolism of benz[j]aceanthrylene-9,10-dihydrodiol, the precursor to bay-region metabolism of the genotoxic cyclopenta-PAH benz[j]aceanthrylene.

    PubMed

    Newcomb, K O; Sangaiah, R; Gold, A; Ball, L M

    1993-06-01

    Benz[j]aceanthrylene, a cyclopentafused polycylic aromatic hydrocarbon produced in combustion emissions, possesses a bay region and an etheno bridge which may both contribute to the overall genotoxicity of the compound. In order to assess the role of activation at the bay region, the precursor epoxide benz[j]aceanthrylene 9,10-oxide, its dehydration product 10-hydroxybenz[j]aceanthrylene, the key dihydrodiol 9,10-dihydroxy-9,10-dihydrobenz[j]aceanthrylene and the bay-region diol-epoxide 7,8-epoxy-9,10-dihydroxy-7,8,9,10- tetrahydrobenz[j]aceanthrylene were evaluated in the bacterial histidine-reversion plate incorporation assay (Ames assay) with Salmonella typhimurium strain TA98. The diol-epoxide alone showed direct-acting mutagenicity (10 revertants per nmole), which was decreased by addition of exogenous metabolic activation (Aroclor 1254-treated rat-liver S9), whereas all the other compounds tested were activated by increasing concentrations of S9. The potency of the diol-epoxide was not sufficient to account for the activity of the parent compound. Identification by proton nuclear magnetic resonance and mass spectrometry of the major products of further metabolism by Aroclor 1254-treated rat-liver S9 of the bay region precursor dihydrodiol 9,10-dihydroxy-9,10-dihydrobenz[j]aceanthrylene indicated that oxidation occurred predominantly at the etheno bridge, to give 9,10-dihydroxy-9,10-dihydrobenz[j]aceanthrylene-2(1H)-one, arising by (non-enzymic) rearrangement of the etheno bridge epoxide and the tetrol 1,2,9,10-tetrahydroxy-1,2,9,10- tetrahydrobenz[j]aceanthrylene. The bay region tetrol 7,8,9,10-tetrahydroxy-7,8,9,10-tetrahydrobenz[j] aceanthrylene was observed, implying further bay-region metabolism; re-aromatization of the benzo ring to benz[j]aceanthrylene-9,10-diol also occurred. Thus oxidation at the etheno bridge accounts for the majority of the activity of benz[j]aceanthrylene and its derivatives when Aroclor 1254-treated rat-liver S9 is used for

  16. Benzo(a)pyrene metabolites: formation in rat liver cell-culture lines, binding to macromolecules, and mutagenesis in V79 hamster cells

    SciTech Connect

    Selkirk, J.K.; MacLeod, M.C.; Kuroki, T.; Drevon, C.; Piccoli, C.; Montesano, R.

    1982-01-01

    Benzo(a)pyrene was metabolized in liver cell lines derived from BD-IV and BD-VI rats which included several chemically-transformed lines (IAR-6-1; IAR-19; IAR-28), one spontaneous transformant (IAR-27) as well as one nonmalignant line (IAR-20). Cultures were treated with tritiated benzo(a)pyrene over a 5-day period. The cells and medium were extracted with ethyl acetate and the distribution between organic-soluble and water-soluble metabolites determined. Organic-soluble metabolites consisting of dihydrodiols, phenols and quinones were determined by high-pressure liquid chromatography, and macromolecular binding of BP to each cell line was measured over a 24-h period. Comparisons between binding and overall metabolism were not directly proportional in these liver cell lines. However, there was a positive correlation for benzo(a)pyrene mutagenesis in the V-79 hamster cell assay with 8-azaguanine as a marker when the cell lines with the highest (IAR-20) and lowest (IAR-27) metabolic competence were used as activating cell layers.

  17. Kinetics of lactate transport into rat liver in vivo

    SciTech Connect

    Lupo, M.A.; Cefalu, W.T.; Pardridge, W.M.

    1990-04-01

    Lactate clearance by liver plays an important role in lactate homeostasis and in the development of lactic acidosis. The role of lactate delivery to liver as a limiting factor in hepatic uptake of lactate is unclear. Lactate delivery of mechanisms could be important if rates of lactate transport approximate rates of lactate metabolism by liver. The rates of lactate transport into liver have been determined in vitro with isolated liver cells and the results have been conflicting. Therefore, the present studies measure the rate of transport of (14C)-L-lactate, and its poorly metabolizeable stereoisomer, (14C)-D-lactate, into rat liver in vivo using a portal vein injection technique. The transport of (3H)-water and of (14C)-sucrose, an extracellular reference compound, were also studied. Portal blood flow was determined from the kinetics of (3H)-water efflux in liver and was 1.93 +/- 0.22 mL/min/g. The volumes of distribution of (14C)-L-lactate, and (14C)-sucrose were 1.31 +/- 0.22, 0.71 +/- 0.07, and 0.22 +/- 0.07 mL/g, respectively. The extraction of unidirectional influx of (14C)-L-lactate and (14C)-D-lactate by rat liver was 93% +/- 10% and 91% +/- 9%, respectively. The rate of lactate transport into rat liver in vivo, 1.8 mumols.min-1.g-1, is approximately twofold greater than the rate of lactate metabolism by rat liver reported in the literature. Therefore, lactate uptake by liver may not be limited by transport under normal conditions. However, conditions such as decreased portal blood flow, which slow lactate delivery to liver by 50% or more, could cause lactate uptake by liver to be limited by transport of circulating lactate.

  18. Liver fibrosis impairs hepatic pharmacokinetics of liver transplant drugs in the rat model.

    PubMed

    Zou, Yu-Hong; Liu, Xin; Khlentzos, Alexander M; Asadian, Peyman; Li, Peng; Thorling, Camilla A; Robertson, Thomas A; Fletcher, Linda M; Crawford, Darrell H G; Roberts, Michael S

    2010-01-01

    This study aims to investigate hepatic pharmacokinetics of the four most common drugs (metoprolol, omeprazole, spironolactone, and furosemide) given to patients undergoing liver transplantation before surgery. The investigation was carried out in CCl(4)-induced fibrotic perfused rat livers and the results were compared to those in normal rat liver. Drug outflow fraction-time profiles were obtained after bolus injection into a single-pass-perfused normal or fibrotic rat liver. The pharmacokinetic parameters were estimated using previously developed barrier-limited and space-distributed models. The results showed a marked increase in the liver fibrosis index for CCl(4)-treated rats compared to controls (p<0.05). The extraction ratios (E) for all drugs were significantly lower (p<0.05) in fibrotic than in normal livers and the decrease in E was consistent with the decrease in intrinsic clearance and permeability-surface area product. In addition, other than for furosemide, the mean transit times for all drugs were significantly longer (p<0.01) in the fibrotic livers than in normal livers. Pharmacokinetic model and stepwise regression analyses suggest that these differences arise from a reduction in both the transport of drugs across the basolateral membrane and their metabolic clearance and were in a manner similar to those previously found for another group of drugs.

  19. Reduced liver uptake of arterially infused melphalan during retrograde rat liver perfusion with unaffected liver tumor uptake.

    PubMed

    Rothbarth, Joost; Sparidans, Rolf W; Beijnen, Jos H; Schultze-Kool, Leo J; Putter, Hein; van de Velde, Cornelis J H; Mulder, Gerard J

    2002-11-01

    Isolated hepatic perfusion (IHP) with melphalan is used for patients with nonresectable metastases confined to the liver. To improve the efficacy of IHP and to reduce the toxicity to the liver, reversion (retrograde perfusion) of the bloodstream through the liver in a rat model was studied. For liver tumor induction male WAG/Rij rats were inoculated with CC531 cells, a colorectal tumor cell line. After 11 to 12 days the tumor-bearing rat livers were perfused by single-pass perfusion through either the portal (orthograde) or caval vein (retrograde) for different time periods. During perfusion melphalan (160 Schultze) was infused in the hepatic artery. Melphalan concentrations were measured by high-performance liquid chromatography. A rapid extraction of melphalan by the liver occurred in the first 5 min, reaching steady state after 10 to 20 min for both perfusion directions. The melphalan concentration of the outflow perfusate was significantly higher in the retrograde perfusion compared with the orthograde perfusion. The melphalan content of the tumor tissue was unaffected by perfusion direction at any time point. To the contrary, the melphalan uptake in liver tissue was strongly influenced: the melphalan content after 40-min retrograde perfusion was 12% of that after orthograde perfusion. The average tumor/liver concentration ratio was 6 for orthograde perfusion and 30 for retrograde perfusion. In conclusion, retrograde IHP with continuous melphalan infusion in the hepatic artery provides a high tumor uptake of melphalan with potentially reduced liver toxicity compared with orthograde IHP. PMID:12388659

  20. Supercooling Preservation Of The Rat Liver For Transplantation

    PubMed Central

    Bruinsma, Bote G.; Berendsen, Tim A.; Izamis, Maria-Louisa; Yeh, Heidi; Yarmush, Martin L.; Uygun, Korkut

    2015-01-01

    The current standard for liver preservation is limited in duration. Employing a novel subzero preservation technique that includes supercooling and machine perfusion can significantly improve preservation and prolong storage times. By loading rat livers with cryoprotectants to prevent both intra- and extracellular ice formation and protect against hypothermic injury, livers can be cooled to −6 °C without freezing and kept viable for up to 96 hours. Here, we describe the procedures of loading cryoprotectants by means of subnormothermic machine perfusion (SNMP), controlled cooling to a supercooled state, followed by SNMP recovery and orthotopic liver transplantation. PMID:25692985

  1. Evidence for bay region activation of chrysene 1,2-dihydrodiol to an ultimate carcinogen.

    PubMed

    Levin, W; Wood, A W; Chang, R L; Yagi, H; Mah, H D; Jerina, D M; Conney, A H

    1978-06-01

    The tumor-initiating activities of chrysene and the three metabolically possible trans-dihydrodiols at the 1,2-, 3,4-, and 5,6-positions of chyrsene were determined on the skin of female CD-1 mice. A single topical application of 0.4, 1.25, or 4.0 mumol of each compound was followed 7 days later by twice-weekly applications of the tumor promoter 12-O-tetradecanoylphorbol-13-acetate for 25 weeks. The most potent tumor initiator was chrysene 1,2-dihydrodiol, which had approximately twice the tumorigenic activity of the parent hydrocarbon chrysene at all doses tested. Chrysene 3,4-dihydrodiol and chrysene 5,6-dihydrodiol had no significant tumorigenic activity. 1,2-Dihydroxy-1,2,3,4-tetrahydrochrysene, a compound related to chrysene 1,2-dihydrodiol but with the conjugated nonaromatic double bond removed from the 3,4-position of the molecule, had less than 25% of the tumorigenic activity of chrysene 1,2-dihydrodiol. These results indicate that chrysene 1,2-dihydrodiol is a proximate carcinogenic metabolite of chrysene and that a chrysene 1,2-diol-3,4-epoxide, in which the epoxide group forms part of the bay region in the molecule, is a likely candidate as an ultimate carcinogenic metabolite of chrysene.

  2. Modeling the mechanical properties of liver fibrosis in rats.

    PubMed

    Zhu, Ying; Chen, Xin; Zhang, Xinyu; Chen, Siping; Shen, Yuanyuan; Song, Liang

    2016-06-14

    The progression of liver fibrosis changes the biomechanical properties of liver tissue. This study characterized and compared different liver fibrosis stages in rats in terms of viscoelasticity. Three viscoelastic models, the Voigt, Maxwell, and Zener models, were applied to experimental data from rheometer tests and then the elasticity and viscosity were estimated for each fibrosis stage. The study found that both elasticity and viscosity are correlated with the various stages of liver fibrosis. The study revealed that the Zener model is the optimal model for describing the mechanical properties of each fibrosis stage, but there is no significant difference between the Zener and Voigt models in their performance on liver fibrosis staging. Therefore the Voigt model can still be effectively used for liver fibrosis grading. PMID:27017300

  3. Serial analysis of gene expression (SAGE) in rat liver regeneration

    SciTech Connect

    Cimica, Velasco . E-mail: vcimica@aecom.yu.edu; Batusic, Danko; Haralanova-Ilieva, Borislava; Chen, Yonglong; Hollemann, Thomas; Pieler, Tomas; Ramadori, Giuliano

    2007-08-31

    We have applied serial analysis of gene expression for studying the molecular mechanism of the rat liver regeneration in the model of 70% partial hepatectomy. We generated three SAGE libraries from a normal control liver (NL library: 52,343 tags), from a sham control operated liver (Sham library: 51,028 tags), and from a regenerating liver (PH library: 53,061 tags). By SAGE bioinformatics analysis we identified 40 induced genes and 20 repressed genes during the liver regeneration. We verified temporal expression of such genes by real time PCR during the regeneration process and we characterized 13 induced genes and 3 repressed genes. We found connective tissue growth factor transcript and protein induced very early at 4 h after PH operation before hepatocytes proliferation is triggered. Our study suggests CTGF as a growth factor signaling mediator that could be involved directly in the mechanism of liver regeneration induction.

  4. Oxidation of PAH trans-Dihydrodiols by Human Aldo-Keto Reductase AKR1B10

    PubMed Central

    Quinn, Amy M.; Harvey, Ronald G.; Penning, Trevor M.

    2009-01-01

    AKR1B10 has been identified as a potential biomarker for human non-small cell lung carcinoma and as a tobacco exposure and response gene. AKR1B10 functions as an efficient retinal reductase in vitro, and may regulate retinoic acid homeostasis. However, the possibility that this enzyme is able to activate polycyclic aromatic hydrocarbon (PAH) trans-dihydrodiols to form reactive and redox-active o-quinones has not been investigated to date. AKR1B10 was found to oxidize a wide range of PAH trans-dihydrodiol substrates in vitro to yield PAH o-quinones. Reactions of AKR1B10 proceeded with improper stereochemistry, since it was specific for the minor (+)-benzo[a]pyrene-7S,8S-dihydrodiol diastereomer formed in vivo. However, AKR1B10 displayed reasonable activity in the oxidation of both the (−)-R,R and (+)-S,S stereoisomers of benzo[g]chrysene-11,12-dihydrodiol and oxidized the potentially relevant, albeit minor, (+)-benz[a]anthracene-3S,4S-dihydrodiol metabolite. We find that AKR1B10 is therefore likely to play a contributing role in the activation of PAH trans-dihydrodiols in human lung. AKR1B10 retinal reductase activity was confirmed in vitro and found to be 5- to 150-fold greater than the oxidation of PAH trans-dihydrodiols examined. AKR1B10 was highly expressed at the mRNA and protein levels in human lung adenocarcinoma A549 cells, and robust retinal reductase activity was measured in lysates of these cells. The much greater catalytic efficiency of retinal reduction compared to PAH trans-dihydrodiol metabolism suggests AKR1B10 may play a greater role in lung carcinogenesis through dysregulation of retinoic acid homeostasis than through oxidation of PAH trans-dihydrodiols. PMID:18788756

  5. Impact of Propionic Acid on Liver Damage in Rats

    PubMed Central

    Al- Daihan, Sooad; Shafi Bhat, Ramesa

    2015-01-01

    Propionic acid (PA) is a short chain fatty acid, a common food preservative and metabolic end product of enteric bacteria in the gut. The present study was undertaken to investigate the effect of PA on liver injury in male rats. Male western albino rats were divided into two groups. The first group served as normal control, the second was treated with PA. The activities of serum hepatospecific markers such as aspartate transaminase, alanine transaminase, and alkaline phosphatase were estimated. Antioxidant status in liver tissues was estimated by determining the level of lipid peroxidation and activities of enzymatic and non-enzymatic antioxidants. Sodium and potassium levels were also measured in liver tissue. PA treatment caused significant changes in all hepatospecific markers. Biochemical analysis of liver homogenates from PA-treated rats showed an increase in oxidative stress markers like lipid peroxidation and lactate dehydrogenase, coupled with a decrease in glutathione, vitamin C and glutathione S- transferase. However, PA exposure caused no change in sodium and potassium levels in liver tissue. Our study demonstrated that PA persuade hepatic damage in rats. PMID:26629488

  6. Supercooling preservation and transplantation of the rat liver.

    PubMed

    Bruinsma, Bote G; Berendsen, Tim A; Izamis, Maria-Louisa; Yeh, Heidi; Yarmush, Martin L; Uygun, Korkut

    2015-03-01

    The current standard for liver preservation involves cooling of the organ on ice (0-4 °C). Although it is successful for shorter durations, this method of preservation does not allow long-term storage of the liver. The gradual loss of hepatic viability during preservation puts pressure on organ sharing and allocation, may limit the use of suboptimal grafts and necessitates rushed transplantation to achieve desirable post-transplantation outcomes. In an attempt to improve and prolong liver viability during storage, alternative preservation methods are under investigation. For instance, ex vivo machine perfusion systems aim to sustain and even improve viability by supporting hepatic function at warm temperatures, rather than simply slowing down deterioration by cooling. Here we describe a novel subzero preservation technique that combines ex vivo machine perfusion with cryoprotectants to facilitate long-term supercooled preservation. The technique improves the preservation of rat livers to prolong storage times as much as threefold, which is validated by successful long-term recipient survival after orthotopic transplantation. This protocol describes how to load rat livers with cryoprotectants to prevent both intracellular and extracellular ice formation and to protect against hypothermic injury. Cryoprotectants are loaded ex vivo using subnormothermic machine perfusion (SNMP), after which livers can be cooled to -6 °C without freezing and kept viable for up to 96 h. Cooling to a supercooled state is controlled, followed by 3 h of SNMP recovery and orthotopic liver transplantation.

  7. Reconstitution of liver mass via cellular hypertrophy in the rat.

    PubMed

    Nagy, P; Teramoto, T; Factor, V M; Sanchez, A; Schnur, J; Paku, S; Thorgeirsson, S S

    2001-02-01

    The liver has an extremely effective regenerative capacity. When 70% of a rat liver is removed by surgery, the liver mass regrows in 7 to 10 days by the compensatory hyperplasia of the remnant part. In case of damage to the surviving hepatocytes, the facultative stem-cell compartment is activated and the liver regenerates by means of oval-cell proliferation/differentiation. In the present study, we demonstrate that when both hepatocyte proliferation and stem-cell activation were prevented by dexamethasone (Dex) administration, the liver mass was restored in the absence of DNA synthesis. The restoration of the liver was accomplished by the preferential enlargement/hypertrophy of the periportal hepatocytes. A similar response was observed when cell proliferation was arrested by 5-fluorouracil (FU) following partial hepatectomy. Therefore, the hepatocytic hypertrophy appears to provide an alternative mechanism of liver-mass restoration. This hypertrophic condition of the liver is not stable, because following the withdrawal of Dex, the enlarged hepatocytes entered in the cell cycle and the normal liver structure and DNA content was re-established. PMID:11172335

  8. Effects of hypergravity on rat liver regeneration

    NASA Technical Reports Server (NTRS)

    Feller, D. D.

    1982-01-01

    The effects of centrifugation on liver regrowth were examined by measuring mitotic activity. The results indicate that the increased gravity caused a delay in the onset of mitotic activity and a significant decrease in overall mitotic activity.

  9. Creatine supplementation and oxidative stress in rat liver

    PubMed Central

    2013-01-01

    Background The objective of this study was to determine the effects of creatine supplementation on liver biomarkers of oxidative stress in exercise-trained rats. Methods Forty 90-day-old adult male Wistar rats were assigned to four groups for the eight-week experiment. Control group (C) rats received a balanced control diet; creatine control group (CCr) rats received a balanced diet supplemented with 2% creatine; trained group (T) rats received a balanced diet and intense exercise training equivalent to the maximal lactate steady state phase; and supplemented-trained (TCr) rats were given a balanced diet supplemented with 2% creatine and subjected to intense exercise training equivalent to the maximal lactate steady state phase. At the end of the experimental period, concentrations of creatine, hydrogen peroxide (H2O2) and thiobarbituric acid reactive substances (TBARS) were measured as well as the enzyme activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-GPx) and catalase (CAT). Liver tissue levels of reduced glutathione (GSH), oxidized glutathione (GSSG) and the GSH/GSSG ratio were also determined. Results Hepatic creatine levels were highest in the CCr and TCr groups with increased concentration of H2O2 observed in the T and TCr animal groups. SOD activity was decreased in the TCr group. GSH-GPx activity was increased in the T and TCr groups while CAT was elevated in the CCr and TCr groups. GSH, GGS and the GSH/GSSG ratio did not differ between all animal subsets. Conclusions Our results demonstrate that creatine supplementation acts in an additive manner to physical training to raise antioxidant enzymes in rat liver. However, because markers of liver oxidative stress were unchanged, this finding may also indicate that training-induced oxidative stress cannot be ameliorated by creatine supplementation. PMID:24325803

  10. IN VITRO METABOLISM OF PYRETHROIDS IN RAT LIVER MICROSOMES

    EPA Science Inventory


    IN VITRO METABOLISM OF PYRETHROIDS IN RAT LIVER MICROSOMES

    SJ Godin1, RA Harrison2 MF. Hughes 2, MJ DeVito2; 1Curriculum In Toxicology, UNC-CH, Chapel Hill NC, USA; 2ETD, NHEERL, ORD, US EPA, RTP, NC, 27711, USA.

    Pyrethroids are neurotoxic pesticides that bin...

  11. Molecular cloning, expression and catalytic activity of a human AKR7 member of the aldo-keto reductase superfamily: evidence that the major 2-carboxybenzaldehyde reductase from human liver is a homologue of rat aflatoxin B1-aldehyde reductase.

    PubMed Central

    Ireland, L S; Harrison, D J; Neal, G E; Hayes, J D

    1998-01-01

    The masking of charged amino or carboxy groups by N-phthalidylation and O-phthalidylation has been used to improve the absorption of many drugs, including ampicillin and 5-fluorouracil. Following absorption of such prodrugs, the phthalidyl group is hydrolysed to release 2-carboxybenzaldehyde (2-CBA) and the pharmaceutically active compound; in humans, 2-CBA is further metabolized to 2-hydroxymethylbenzoic acid by reduction of the aldehyde group. In the present work, the enzyme responsible for the reduction of 2-CBA in humans is identified as a homologue of rat aflatoxin B1-aldehyde reductase (rAFAR). This novel human aldo-keto reductase (AKR) has been cloned from a liver cDNA library, and together with the rat protein, establishes the AKR7 family of the AKR superfamily. Unlike its rat homologue, human AFAR (hAFAR) appears to be constitutively expressed in human liver, and is widely expressed in extrahepatic tissues. The deduced human and rat protein sequences share 78% identity and 87% similarity. Although the two AKR7 proteins are predicted to possess distinct secondary structural features which distinguish them from the prototypic AKR1 family of AKRs, the catalytic- and NADPH-binding residues appear to be conserved in both families. Certain of the predicted structural features of the AKR7 family members are shared with the AKR6 beta-subunits of voltage-gated K+-channels. In addition to reducing the dialdehydic form of aflatoxin B1-8,9-dihydrodiol, hAFAR shows high affinity for the gamma-aminobutyric acid metabolite succinic semialdehyde (SSA) which is structurally related to 2-CBA, suggesting that hAFAR could function as both a SSA reductase and a 2-CBA reductase in vivo. This hypothesis is supported in part by the finding that the major peak of 2-CBA reductase activity in human liver co-purifies with hAFAR protein. PMID:9576847

  12. Melatonin Alleviates Liver Apoptosis in Bile Duct Ligation Young Rats

    PubMed Central

    Sheen, Jiunn-Ming; Chen, Yu-Chieh; Hsu, Mei-Hsin; Tain, You-Lin; Huang, Ying-Hsien; Tiao, Mao-Meng; Li, Shih-Wen; Huang, Li-Tung

    2016-01-01

    Bile duct ligation (BDL)-treated rats display cholestasis and liver damages. The potential protective activity of melatonin in young BDL rats in terms of apoptosis, mitochondrial function, and endoplasmic reticulum (ER) homeostasis has not yet been evaluated. Three groups of young male Sprague-Dawley rats were used: one group received laparotomy (Sham), a second group received BDL for two weeks (BDL), and a third group received BDL and intraperitoneal melatonin (100 mg/day) for two weeks (BDL + M). BDL group rats showed liver apoptosis, increased pro-inflamamtory mediators, caspases alterations, anti-apoptotic factors changes, and dysfunction of ER homeostasis. Melatonin effectively reversed apoptosis, mainly through intrinsic pathway and reversed ER stress. In addition, in vitro study showed melatonin exerted its effect mainly through the melatonin 2 receptor (MT2) in HepG2 cells. In conclusion, BDL in young rats caused liver apoptosis. Melatonin rescued the apoptotic changes via the intrinsic pathway, and possibly through the MT2 receptor. Melatonin also reversed ER stress induced by BDL. PMID:27556445

  13. Melatonin Alleviates Liver Apoptosis in Bile Duct Ligation Young Rats.

    PubMed

    Sheen, Jiunn-Ming; Chen, Yu-Chieh; Hsu, Mei-Hsin; Tain, You-Lin; Huang, Ying-Hsien; Tiao, Mao-Meng; Li, Shih-Wen; Huang, Li-Tung

    2016-01-01

    Bile duct ligation (BDL)-treated rats display cholestasis and liver damages. The potential protective activity of melatonin in young BDL rats in terms of apoptosis, mitochondrial function, and endoplasmic reticulum (ER) homeostasis has not yet been evaluated. Three groups of young male Sprague-Dawley rats were used: one group received laparotomy (Sham), a second group received BDL for two weeks (BDL), and a third group received BDL and intraperitoneal melatonin (100 mg/day) for two weeks (BDL + M). BDL group rats showed liver apoptosis, increased pro-inflamamtory mediators, caspases alterations, anti-apoptotic factors changes, and dysfunction of ER homeostasis. Melatonin effectively reversed apoptosis, mainly through intrinsic pathway and reversed ER stress. In addition, in vitro study showed melatonin exerted its effect mainly through the melatonin 2 receptor (MT2) in HepG2 cells. In conclusion, BDL in young rats caused liver apoptosis. Melatonin rescued the apoptotic changes via the intrinsic pathway, and possibly through the MT2 receptor. Melatonin also reversed ER stress induced by BDL. PMID:27556445

  14. Antiulcer activity of cod liver oil in rats

    PubMed Central

    Khare, Salaj; Asad, Mohammed; Dhamanigi, Sunil S.; Prasad, V. Satya

    2008-01-01

    Objective: Cod liver oil is used widely as a dietary supplement. The present study was carried out to evaluate the effect of cod liver oil (0.5 g/kg, p.o. and 1 g/kg, p.o.) on gastric and duodenal ulcers. Materials and Methods: The study was carried out on different gastric ulcer models such as acetic acid induced chronic gastric ulcers, pylorus ligation, indomethacin induced ulcers, stress induced ulcers and ethanol induced ulcers. The duodenal ulcers were induced using cysteamine hydrochloride (HCl). Ranitidine (50 mg/kg p.o.) and misoprostol (100 µg/kg, p.o.) were used as standard drugs. Results: Both doses of cod liver oil showed gastric ulcer healing effect in acetic acid induced chronic gastric ulcers, produced gastric antisecretory effect in pylorus-ligated rats and also showed gastric cytoprotective effect in ethanol-induced and indomethacin-induced ulcer. Cod liver oil also produced a significant reduction in the development of stress induced gastric ulcers and cysteamine induced duodenal ulcer. The high dose of cod liver oil (1 g/kg, p.o.) was more effective compared to the low dose (0.5 g/kg, p.o.). Conclusion: Cod liver oil increases healing of gastric ulcers and prevents the development of experimentally induced gastric and duodenal ulcers in rats. PMID:20040959

  15. Characterization of deltamethrin metabolism by rat plasma and liver microsomes

    SciTech Connect

    Anand, Sathanandam S. . E-mail: sanand@rx.uga.edu; Bruckner, James V.; Haines, Wendy T.; Muralidhara, Srinivasa; Fisher, Jeffrey W.; Padilla, Stephanie

    2006-04-15

    Deltamethrin, a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. While the toxicity has been extensively examined, toxicokinetic studies of deltamethrin and most other pyrethroids are very limited. The aims of this study were to identify, characterize, and assess the relative contributions of esterases and cytochrome P450s (CYP450s) responsible for deltamethrin metabolism by measuring deltamethrin disappearance following incubation of various concentrations (2 to 400 {mu}M) in plasma (esterases) and liver microsomes (esterases and CYP450s) prepared from adult male rats. While the carboxylesterase metabolism in plasma and liver was characterized using an inhibitor, tetra isopropyl pyrophosphoramide (isoOMPA), CYP450 metabolism was characterized using the cofactor, NADPH. Michaelis-Menten rate constants were calculated using linear and nonlinear regression as applicable. The metabolic efficiency of these pathways was estimated by calculating intrinsic clearance (Vmax/Km). In plasma, isoOMPA completely inhibited deltamethrin biotransformation at concentrations (2 and 20 {mu}M of deltamethrin) that are 2- to 10-fold higher than previously reported peak blood levels in deltamethrin-poisoned rats. For carboxylesterase-mediated deltamethrin metabolism in plasma, Vmax = 325.3 {+-} 53.4 nmol/h/ml and Km = 165.4 {+-} 41.9 {mu}M. Calcium chelation by EGTA did not inhibit deltamethrin metabolism in plasma or liver microsomes, indicating that A-esterases do not metabolize deltamethrin. In liver microsomes, esterase-mediated deltamethrin metabolism was completely inhibited by isoOMPA, confirming the role of carboxylesterases. The rate constants for liver carboxylesterases were Vmax = 1981.8 {+-} 132.3 nmol/h/g liver and Km = 172.5 {+-} 22.5 {mu}M. Liver microsomal CYP450-mediated biotransformation of deltamethrin was a higher capacity (Vmax = 2611.3 {+-} 134.1 nmol/h/g liver) and higher affinity (Km = 74.9 {+-} 5.9 {mu}M) process than

  16. Oral administration of polyamines ameliorates liver ischemia/reperfusion injury and promotes liver regeneration in rats.

    PubMed

    Okumura, Shinya; Teratani, Takumi; Fujimoto, Yasuhiro; Zhao, Xiangdong; Tsuruyama, Tatsuaki; Masano, Yuki; Kasahara, Naoya; Iida, Taku; Yagi, Shintaro; Uemura, Tadahiro; Kaido, Toshimi; Uemoto, Shinji

    2016-09-01

    Polyamines are essential for cell growth and differentiation. They play important roles in protection from liver damage and promotion of liver regeneration. However, little is known about the effect of oral exogenous polyamine administration on liver damage and regeneration. This study investigated the impact of polyamines (spermidine and spermine) on ischemia/reperfusion injury (IRI) and liver regeneration. We used a rat model in which a 70% hepatectomy after 40 minutes of ischemia was performed to mimic the clinical condition of living donor partial liver transplantation (LT). Male Lewis rats were separated into 2 groups: a polyamine group given polyamines before and after operation as treatment and a vehicle group given distilled water as placebo. The levels of serum aspartate aminotransferase and alanine aminotransferase at 6, 24, and 48 hours after reperfusion were significantly lower in the polyamine group compared with those in the vehicle group. Polyamine treatment reduced the expression of several proinflammatory cytokines and chemokines at 6 hours after reperfusion. Histological analysis showed significantly less necrosis and apoptosis in the polyamine group at 6 hours after reperfusion. Sinusoidal endothelial cells were also well preserved in the polyamine group. In addition, the regeneration of the remnant liver at 24, 48, and 168 hours after reperfusion was significantly accelerated, and the Ki-67 labeling index and the expressions of proliferating cell nuclear antigen and phosphorylated retinoblastoma protein at 24 hours after reperfusion were significantly higher in the polyamine group compared with those in the vehicle group. In conclusion, perioperative oral polyamine administration attenuates liver IRI and promotes liver regeneration. It might be a new therapeutic option to improve the outcomes of partial LT. Liver Transplantation 22 1231-1244 2016 AASLD. PMID:27102080

  17. Electrophoretically unique amylases in rat livers: phylogenic and ontogenic study on the mammalian liver.

    PubMed

    Koyama, Iwao; Komine, Shin-Ichi; Hokari, Shigeru; Matsunaga, Toshiyuki; Nakamura, Koh-Ich; Komoda, Tsugikazu

    2002-09-01

    Liver amylase activity in rodents was assayed with Blue Starch as substrate, and found to be higher than in humans or pigs. Based on the result of concanavalin A affinity chromatography, we found that the sugar moieties of amylase molecules increased in parallel with amylase activity in the tested mammals. However, the amounts of amylase proteins determined by Western bloting with anti-human salivary-type antibody as the probe, were similar to the levels in mammalian livers. Moreover, a similar expression of amylase mRNA was also detected in the mammalian livers by a reverse transcriptional-polymerase chain reaction using primers specific for the human salivary and/or pancreatic amylase complementary DNA (cDNA) sequences. The amylase was detected at the catalytic activity, protein molecule and mRNA levels in rat liver at all ages from fetus to adult. Salivary-type liver amylase activity increased up to one week after birth, and was maintained at the adult level thereafter. However, based on the results of the electrophoretic mobility test, livers with accelerated amylase activity, e.g., at 2-4 weeks after birth or during liver regeneration after partial hepatectomy, were also found to express an amylase electrophoretical identical to pancreatic-type amylase in addition to salivary-type activity. These results suggest that the liver may express an etopic amylase in a certain condition.

  18. Sialyltransferase activity in regenerating rat liver

    PubMed Central

    Serafini-Cessi, Franca

    1977-01-01

    Liver microsomal fractions catalyse the transfer of sialic acid from CMP-N-acetyl-neuraminic acid to various exogenous acceptors such as desialylated fetuin, desialylated human Tamm–Horsfall glycoprotein and desialylated bovine submaxillary-gland mucin. An increase in the rate of incorporation of sialic acid into desialylated glycoproteins was found after a lag period (7h) in regenerating liver. The increase was maximum 24h after partial hepatectomy for all acceptors tested. At later times after operation the sialyltransferase activity remained high only for desialylated fetuin. No soluble factors from liver or serum of partially hepatectomized animals influenced the activity of the sialyltransferases bound to the microsomal fraction. The sensitivity of sialyltransferases to activation by Triton X-100, added to the incubation medium, was unchanged in the microsomal preparation from animals 24h after sham operation or partial hepatectomy. The full activity of sialyltransferases towards the various desialylated acceptors showed some differences. Human Tamm–Horsfall glycoprotein was a good acceptor of sialic acid only when desialylated by mild acid hydrolysis. After this treatment, but not after enzymic hydrolysis, a decrease in molecular weight of human Tamm–Horsfall glycoprotein was observed. Further, the sialyltransferase activity as a function of incubation temperature gave different curves according to the acceptor used. The relationship between the biosynthesis of glycoproteins by regenerating liver and the sialyltransferase activity of microsomal fraction after partial hepatectomy is discussed. PMID:597233

  19. Borax counteracts genotoxicity of aluminum in rat liver.

    PubMed

    Turkez, Hasan; Geyikoğlu, Fatime; Tatar, Abdulgani

    2013-10-01

    This study was carried out to evaluate the protective role of borax (BX) on genotoxicity induced by aluminum (Al) in rat liver, using liver micronucleus assay as an indicator of genotoxicity. Sprague-Dawley rats were randomly separated into six groups and each group had four animals. Aluminum chloride (AlCl₃; 5 mg/kg b.w.) and BX (3.25 and 13 mg/kg b.w.) were injected intraperitoneally to rats. Besides, animals were also treated with Al for 4 consecutive days followed by BX for 10 days. Rats were anesthetized after Al and BX injections and the hepatocytes were isolated for counting the number of micronucleated hepatocytes (MNHEPs). AlCl₃ was found to significantly (p < 0.05) increase the number of MNHEPs. Rats treated with BX, however, showed no increase in MNHEPs. Moreover, simultaneous treatments with BX significantly modulated the genotoxic effects of AlCl₃ in rats. It can be concluded that BX has beneficial influences and has the ability to antagonize Al toxicity. PMID:22491726

  20. Borax counteracts genotoxicity of aluminum in rat liver.

    PubMed

    Turkez, Hasan; Geyikoğlu, Fatime; Tatar, Abdulgani

    2013-10-01

    This study was carried out to evaluate the protective role of borax (BX) on genotoxicity induced by aluminum (Al) in rat liver, using liver micronucleus assay as an indicator of genotoxicity. Sprague-Dawley rats were randomly separated into six groups and each group had four animals. Aluminum chloride (AlCl₃; 5 mg/kg b.w.) and BX (3.25 and 13 mg/kg b.w.) were injected intraperitoneally to rats. Besides, animals were also treated with Al for 4 consecutive days followed by BX for 10 days. Rats were anesthetized after Al and BX injections and the hepatocytes were isolated for counting the number of micronucleated hepatocytes (MNHEPs). AlCl₃ was found to significantly (p < 0.05) increase the number of MNHEPs. Rats treated with BX, however, showed no increase in MNHEPs. Moreover, simultaneous treatments with BX significantly modulated the genotoxic effects of AlCl₃ in rats. It can be concluded that BX has beneficial influences and has the ability to antagonize Al toxicity.

  1. [Reperfusion injury in the isolated rat liver after hypothermic preservation].

    PubMed

    Kopecký, M; Balás, P; Semecký, V; Tilser, I; Rouchalová, E

    2002-03-01

    Histological changes which appear as a result of reperfusion injury of cold-preserved rat liver were studied at intervals of 0 hr, 3 hr, 24 hr and 48 hr of cold storage. The isolated livers were stored in a UW solution (University of Wisconsin), which is used in human liver transplantations. Computer image analysis of light microscopic sections (methyl green-pyronin stained) was used for the study and quantification of injured cells. The method of TUNEL was performed to prove possible apoptosis of sinusoidal endothelial cells and heptocytes. Bile production during reperfusion and ALT, AST, LDH and ACP were measured in the reperfusion medium at the end of the 90 min reperfusion. It has been confirmed that prolongation of the cold storage of liver results in extensive changes in the liver structure and increased injury of liver cells. Sinusoidal endothelial cells were damaged more and earlier than hepatocytes. It has been shown that methyl green-pyronin stained sections are advantageous for the study of these morphological changes, allowing the strongest view of these changes. The appearance of TUNEL positive cells and an increase in the levels of biochemical parameters, e.g. AST or ALT, indicate earlier cell injury. The methodology described in this article can be used for the study of reperfusion injury of the liver and for the study of this phenomenon in other experiments. PMID:11928282

  2. Monoclonal antibodies against the rat liver glucocorticoid receptor.

    PubMed Central

    Okret, S; Wikström, A C; Wrange, O; Andersson, B; Gustafsson, J A

    1984-01-01

    Splenic cells from one BALB/c mouse and one C57/BL mouse, immunized with purified rat liver glucocorticoid receptor (GR), were fused with the mouse myeloma cell line Sp 2/0-Ag 14. Screening for production of anti-GR-antibodies by the hybridomas was carried out with an enzyme-linked immunosorbent assay, using partially purified rat liver GR as antigen. Further screening was by a second-antibody immunoprecipitation assay using [3H]triamcinolone acetonide-GR complex from rat liver cytosol as tracer. Hybridomas from 10 different microplate wells, positive in both assays, were successfully cloned by the limiting dilution method to monoclonality. The different origins of the monoclonal antibodies were confirmed by their various isoelectric points when analyzed by isoelectric focusing. Four of the monoclonal hybridoma cell lines secreted IgM antibodies; two, IgG1; three, IgG2a; and one, IgG2b. The GR-antibody complex was identified in glycerol density gradients by a shift of the 4S GR to an 8.5S or 19S GR-antibody complex when incubated with monoclonal IgG or IgM antibody, respectively. The 10 monoclonal antibodies recognized different determinants on the GR, all situated on that domain of the receptor that is separate from the ligand and DNA-binding domains. Also, the cross-reactivity to the mouse liver GR varied among the monoclonal antibodies. No cross-reactivity was observed to the human lymphocytic GR. NaDodSO4 electrophoresis of a 0.5% pure GR preparation followed by immunoblotting using one of the monoclonal antibodies identified a single peptide with a molecular weight of 94,000, identical to the purified rat liver GR. Images PMID:6200880

  3. Deferoxamine alleviates liver fibrosis induced by CCl4 in rats.

    PubMed

    Mohammed, Aya; Abd Al Haleem, Ekram N; El-Bakly, Wesam M; El-Demerdash, Ebtehal

    2016-08-01

    Several chronic liver diseases can lead to the occurrence of hepatic fibrosis through the accumulation of iron, which causes induction of oxidative stress and consequently activation of fibrogenesis. The present study was designed to investigate the potential antifibrotic and anti-oxidant effects of deferoxamine (DFO), a well-known iron chelator in an experimental rat model of liver injury using carbon tetrachloride (CCl4 ). First, the potential effective dose of DFO was screened against CCl4 -induced acute hepatotoxicity. Then, rats were co-treated with DFO (300 mg/kg, i.p.) for 6 weeks starting from the third week of CCl4 induction of chronic hepatotoxicity. Liver function was assessed in addition to histopathological examination. Furthermore, oxidative stress and fibrosis markers were assessed. It was found that treatment of animals with DFO significantly counteracted the changes in liver function; histopathological lesions and hepatic iron deposition that were induced by CCl4 . DFO also significantly counteracted the CCl4 -induced lipid peroxidation increase and reduction in antioxidant activities of superoxide dismutase and glutathione peroxidase enzymes. In addition, DFO ameliorated significantly liver fibrosis markers including hydroxyproline, collagen accumulation, and the expression of the hepatic stellate cells (HSCs) activation marker; alpha smooth muscle actin and transforming growth factor-beta (TGF-β). Together, these findings indicate that DFO possesses a potent antifibrotic effect due to its antioxidant properties that counteracted oxidative stress and lipid peroxidation and restored antioxidant enzymes activities as well as reducing HSCs activation and fibrogenesis.

  4. Regulation of fibronectin expression in rat regenerating liver.

    PubMed Central

    Caputi, M; Melo, C A; Baralle, F E

    1995-01-01

    Fibronectin (FN) expression displays a complex regulation that results in precisely defined isoform patterns during different developmental stages, ageing and injury. The qualitative and quantitative changes that are observed derive from modulation of the rate of transcription of the single FN pre-mRNA and its specific differential processing in the EIIIA, EIIIB and V regions of rat FN. The liver is the major source of plasma FN which is characterised by the absence of the EIIIA and EIIIB exons. Here we show that in the rat regenerating liver there is a significant reprogramming of the splicing machinery that results in the synthesis by the liver of up to 17% of EIIIA+ FN linked with all the three V forms. On the other hand the EIIIB+ form is totally absent both in normal and regenerating liver. Furthermore there is a variation of the V pattern observed in the regenerating tissue, the V120 form (linked to both EIIIA+ and EIIIA- messengers) increases from 11 to 32%. The quantitative RT-PCR method was used to estimate the FN transcription rate, before and after partial hepatectomy. We have shown a 3-fold increase in FN mRNA in liver that is specifically linked to the regeneration process and not to the surgical stress. Images PMID:7862527

  5. Liver regeneration in rats administered high levels of carbohydrates.

    PubMed

    Gershbein, L L

    1976-01-01

    Partially hepatectomized male rats were administered high levels of carbohydrates by drinker, in a casein-cellulose synthetic medium and in a commercial meal over a period of 10 days after surgery and the amount of liver regenerating or the increment ascertained; representative hepatic glycogen changes were also followed. Of the carbohydrate solutions, 5% levulose, 5% levulose+5% glucose and 10% sucrose increased the extent of liver regeneration as was also the case with the synthetic diet suplemented with 30 and 60% glucose, 30 and 60% levulose, 30% levulose+30% glucose, 30% each of galactose and the arabinoglactan, Stractan and 60% each of sucrose, honey and unsulphured molasses. The liver increments and glycogen contents were in the control range for animals fed the synthetic diet containing 30% each of lactose, sorbitol, corn starch and raffinose pentahydrate, 5% ascorbic acid and 15% L-arabinose but the liver glycogen was depressed with 30% xylose, a diet which was poorly tolerated; 15% mannitol caused a decrease inthe increment. The incorporation of several sugars into the commercial rat meal, including xylose (11%), raffinose (15%), L-arabinose (8%), D-arabinose (5%), L-sorbose (17%), galactosamine (0.20%) and galactono-gamma-lactone (10%), led to little change over the control increments. In intact rats fed the synthetic diet containing 30% each of glucose, lactose, galactose, sucrose and levulose for an interval of 10 days, the wet and dry liver--body weight ratios were significantly elevated only with the last two sugars but liver glycogen was increased in each instance.

  6. Caffeic acid phenethyl ester inhibits liver fibrosis in rats

    PubMed Central

    Li, Mei; Wang, Xiu-Fang; Shi, Juan-Juan; Li, Ya-Ping; Yang, Ning; Zhai, Song; Dang, Shuang-Suo

    2015-01-01

    AIM: To investigate the hepatoprotective effects and antioxidant activity of caffeic acid phenethyl ester (CAPE) in rats with liver fibrosis. METHODS: A total of 75 male Sprague-Dawley rats were randomly assigned to seven experimental groups: a normal group (n = 10), a vehicle group (n = 10), a model group (n = 15), a vitamin E group (n = 10), and three CAPE groups (CAPE 3, 6 and 12 mg/kg, n = 10, respectively). Liver fibrosis was induced in rats by injecting CCl4 subcutaneously, feeding with high fat forage, and administering 30% alcohol orally for 10 wk. Concurrently, CAPE (3, 6 and 12 mg/kg) was intraperitoneally administered daily for 10 wk. After that, serum total bilirubin (TBil), aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured to assess hepatotoxicity. To investigate antioxidant activity of CAPE, malondialdehyde (MDA), glutathione (GSH) levels, catalase (CAT) and superoxide dismutase (SOD) activities in liver tissue were determined. Moreover, the effect of CAPE on α-smooth muscle actin (α-SMA), a characteristic hallmark of activated hepatic stellate cells (HSCs), and NF-E2-related factor 2 (Nrf2), a key transcription factor for antioxidant systems, was investigated by immunohistochemistry. RESULTS: Compared to the model group, intraperitoneal administration of CAPE decreased TBil, ALT, and AST levels in liver fibrosis rats (P < 0.05), while serum TBil was decreased by CAPE in a dose-dependent manner. In addition, the liver hydroxyproline contents in both the 6 and 12 mg/kg CAPE groups were markedly lower than that in the model group (P < 0.05 and P < 0.001, respectively). CAPE markedly decreased MDA levels and, in turn, increased GSH levels, as well as CAT and SOD activities in liver fibrosis rats compared to the model group (P < 0.05). Moreover, CAPE effectively inhibited α-SMA expression while increasing Nrf2 expression compared to the model group (P < 0.01). CONCLUSION: The protective effects of CAPE against liver

  7. [Effect of rapeseed from different distributors on the rat liver].

    PubMed

    Alvizouri, M

    1993-01-01

    In previous papers it was reported that rapeseed could prevent the development of cirrhosis induced by carbon tetrachloride and at the same time can induce liver regeneration in the rat. In such experiments rapeseed was always obtained from the same distributor "Semillas Berentsen". When reseed of different distributors was used, neither cirrhosis prevention or liver regeneration was observed. The difference among the rapeseed used was that "Semillas Berentsen" utilizes a fungicide to preserve the seed and the other distributors do not use any preservative. This circumstance made think that the active principle responsible for the effects observed is probably the fungicide. PMID:8159903

  8. Hormone-initiated maturation of rat liver mitochondria after birth.

    PubMed Central

    Sutton, R; Pollak, J K

    1980-01-01

    1. The injection of adrenaline, glucagon or cyclic AMP into foetal rats in utero initiates the maturation of energy transduction in rat liver mitochondria before birth. 2. The injection of the beta-blocker, propranolol, prevents this maturation process. 3. The maturation of mitochondrial energy transduction is measured in terms of the increase in the respiratory control index and mitochondrial adenine nucleotide concentration. 4. It is postulated that the actions of the hormones, acting through cyclic AMP, affect glycogenolysis and glycolysis to give rise to transient localized high concentrations of ATP. 5. It is the ATP that acts as the molecular trigger, effecting mitochondrial maturation. PMID:6245641

  9. Inhibitory effects of beryllium chloride on rat liver microsomal enzymes.

    PubMed

    Teixeira, C F; Yasaka, W J; Silva, L F; Oshiro, T T; Oga, S

    1990-04-30

    A single i.v. dose (0.1 mmol Be2+/kg) of beryllium chloride prolonged the duration of pentobarbital-induced sleep and zoxazolamine-induced paralysis, in rats. The effects are correlated with changes of the pharmacokinetic parameters and with the in vitro inhibition of both aliphatic and aromatic hydroxylation of pentobarbital and zoxazolamine. In vitro N-demethylation of meperidine and aminopyrine was partially inhibited while O-demethylation of quinidine was unaffected by liver microsomes of rats pretreated with beryllium salt. The findings give clues that beryllium chloride inhibits some forms of cytochrome P-450, especially those responsible for hydroxylation of substrates, like pentobarbital and zoxazolamine.

  10. Intestinal ischemic preconditioning reduces liver ischemia reperfusion injury in rats

    PubMed Central

    XUE, TONG-MIN; TAO, LI-DE; ZHANG, JIE; ZHANG, PEI-JIAN; LIU, XIA; CHEN, GUO-FENG; ZHU, YI-JIA

    2016-01-01

    The aim of the current study was to investigate whether intestinal ischemic preconditioning (IP) reduces damage to the liver during hepatic ischemia reperfusion (IR). Sprague Dawley rats were used to model liver IR injury, and were divided into the sham operation group (SO), IR group and IP group. The results indicated that IR significantly increased Bax, caspase 3 and NF-κBp65 expression levels, with reduced expression of Bcl-2 compared with the IP group. Compared with the IR group, the levels of AST, ALT, MPO, MDA, TNF-α and IL-1 were significantly reduced in the IP group. Immunohistochemistry for Bcl-2 and Bax indicated that Bcl-2 expression in the IP group was significantly increased compared with the IR group. In addition, IP reduced Bax expression compared with the IR group. The average liver injury was worsened in the IR group and improved in the IP group, as indicated by the morphological evaluation of liver tissues. The present study suggested that IP may alleviates apoptosis, reduce the release of pro-inflammatory cytokines, ameloriate reductions in liver function and reduce liver tissue injury. To conclude, IP provided protection against hepatic IR injury. PMID:26821057

  11. Re-utilization of pyrimidine nucleotides during rat liver regeneration.

    PubMed Central

    Nikolov, E N; Dabeva, M D

    1985-01-01

    The changes in the specific radioactivities of the pool of total acid-soluble uridine nucleotides and of uridine and cytidine components of total cellular and nuclear RNA were monitored in regenerating rat liver for 12 days after partial hepatectomy. Evidence is presented for the re-utilization of pyrimidine nucleotides derived from cytoplasmic RNA degradation for the synthesis of new RNA. The extent of recycling was assessed and the true rate of rRNA turnover determined more accurately. The reutilization of the uridine components of RNA was 7.0%/day during the proliferative and 3.2%/day during the post-proliferative phase, whereas that of the cytidine nucleotides was more pronounced (9.6%/day and 18.1%/day respectively). The results reveal the existence of partial compartmentalization of pyrimidine ribonucleoside triphosphate pools in the nucleus and cytoplasm of rat liver cells. PMID:2408609

  12. Effects of myosmine on antioxidative defence in rat liver.

    PubMed

    Simeonova, Rumyana; Vitcheva, Vessela; Gorneva, Galina; Mitcheva, Mitka

    2012-03-01

    Myosmine [3-(1-pyrrolin-2-yl) pyridine] is an alkaloid structurally similar to nicotine, which is known to induce oxidative stress. In this study we investigated the effects of myosmine on enzymatic and non-enzymatic antioxidative defence in rat liver. Wistar rats received a single i.p. injection of 19 mg kg-1 of myosmine and an oral dose of 190 mg kg-1 by gavage. Nicotine was used as a positive control. Through either route of administration, myosmine altered the hepatic function by decreasing the levels of reduced glutathione, superoxide dismutase, and glutathione peroxidase activities on one hand and by increasing malondialdehyde, catalase, and glutathione reductase activity on the other. Compared to control, both routes caused significant lipid peroxidation in the liver and altered hepatic enzymatic and non-enzymatic antioxidative defences. The pro-oxidant effects of myosmine were comparable with those of nicotine. PMID:22450200

  13. Casein kinase II stimulates rat liver mitochondrial glycerophosphate acyltransferase activity.

    PubMed

    Onorato, Thomas M; Haldar, Dipak

    2002-09-01

    Rat liver mitochondrial glycerophosphate acyltransferase (mtGAT) possesses 14 consensus sites for casein kinase II (CKII) phosphorylation. To study the functional relevance of phosphorylation to the activity of mtGAT, we treated isolated rat liver mitochondria with CKII and found that CKII stimulated mtGAT activity approximately 2-fold. Protein phosphatase-lambda treatment reversed the stimulation of mtGAT by CKII. Labeling of both solubilized and non-solubilized mitochondria with CKII and [gamma-32P]ATP resulted in a 32P-labeled protein of 85kDa, the molecular weight of mtGAT. Our findings suggest that CKII stimulates mtGAT activity by phosphorylation of the acyltransferase. The significance of this observation with respect to hormonal control of the enzyme is discussed.

  14. Role of the autonomic nervous system in rat liver regeneration.

    PubMed

    Xu, Cunshuan; Zhang, Xinsheng; Wang, Gaiping; Chang, Cuifang; Zhang, Lianxing; Cheng, Qiuyan; Lu, Ailing

    2011-05-01

    To study the regulatory role of autonomic nervous system in rat regenerating liver, surgical operations of rat partial hepatectomy (PH) and its operation control (OC), sympathectomy combining partial hepatectomy (SPH), vagotomy combining partial hepatectomy (VPH), and total liver denervation combining partial hepatectomy (TDPH) were performed, then expression profiles of regenerating livers at 2 h after operation were detected using Rat Genome 230 2.0 array. It was shown that the expressions of 97 genes in OC, 230 genes in PH, 253 genes in SPH, 187 genes in VPH, and 177 genes in TDPH were significantly changed in biology. The relevance analysis showed that in SPH, genes involved in stimulus response, immunity response, amino acids and K(+) transport, amino acid catabolism, cell adhesion, cell proliferation mediated by JAK-STAT, Ca(+), and platelet-derived growth factor receptor, cell growth and differentiation through JAK-STAT were up-regulated, while the genes involved in chromatin assembly and disassembly, and cell apoptosis mediated by MAPK were down-regulated. In VPH, the genes associated with chromosome modification-related transcription factor, oxygen transport, and cell apoptosis mediated by MAPK pathway were up-regulated, but the genes associated with amino acid catabolism, histone acetylation-related transcription factor, and cell differentiation mediated by Wnt pathway were down-regulated. In TDPH, the genes related to immunity response, growth and development of regenerating liver, cell growth by MAPK pathway were up-regulated. Our data suggested that splanchnic and vagal nerves could regulate the expressions of liver regeneration-related genes. PMID:21264506

  15. Effects of animal liver and bile extracts on biochemical values of rat ethanol-induced fatty liver.

    PubMed

    Wan, Tien-Chun; Liu, Yu-Tse; Duann, Lan-Tyi; Yu, Kuo-Hui; Chen, Chih-Ming; Lin, Liang-Chuan; Sakata, Ryoichi

    2014-01-01

    The purposes of this study were to assess the improvement of fatty liver induced by ethanol with animal liver and bile extracts. This research aimed to increase the economic values of animal liver and bile extracts and used these to reduce damage of ethanol-induced fatty liver. Extracts came from animal liver and bile, including pig bile powder, pig liver extract, a mixture of pig bile powder and pig liver extract, chicken bile powder, chicken liver extract, and a mixture of chicken bile powder and chicken liver extract, and these were fed to Long-Evans rats. The results showed that rats fed ethanol for long terms could increase values of aspartate transaminase, cholesterol, γ-glutamy-transferase and alkaline phosphatase. Pig bile powder could decrease the values of aspartate transaminase, cholesterol and γ-glutamy-transferase. The significances also decreased on aspartate transaminase, γ-glutamy-transferase and aspartate transaminase, which were carried out with the pig liver extract treatment. These results suggest pig bile and liver extracts have high potential to improve rats' ethanol-induced fatty liver with serum biochemical parameters.

  16. Determination of boron distribution in rat's brain, kidney and liver.

    PubMed

    Pazirandeh, Ali; Jameie, Behnam; Zargar, Maysam

    2009-07-01

    To determine relative boron distribution in rat's brain, liver and kidney, a mixture of boric acid and borax, was used. After transcardial injection of the solution, the animals were sacrificed and the brain, kidney and liver were removed. The coronal sections of certain areas of the brain were prepared by freezing microtome. The slices were sandwiched within two pieces of CR-39. The samples were bombarded in a thermal neutron field of the TRR pneumatic facility. The alpha tracks are registered on CR-39 after being etched in NaOH. The boron distribution was determined by counting these alpha tracks CR-39 plastics. The distribution showed non-uniformity in brain, liver and kidney. PMID:19375929

  17. 4-Nitrocatechol production from rho-nitrophenol by rat liver.

    PubMed

    Chrastil, J; Wilson, J T

    1975-05-01

    Time course studies of rho-nitroanisole O-demethylation revealed formaldehyde production in excess of rho-nitrophenol (PNP) and 4-nitrocatechol (NTC) formation by rat liver microsomes. This indicated that these products (PNP, NTC) were metabolised further. The hydroxylation reaction PNP yields NTC showed substrate and product inhibition and a requirement for reduced nicotinamide adenine dinucleotide phosphate and O2 and was localized in liver microsomes. It was strongly activated by ascorbic acid, cysteine, adenosine triphosphate or hydroxylamine in vitro and enhanced by phenobarbital treatment in vivo. Mercapturic derivatives were metabolized to the corresponding hydroxy compounds with the same speed as their parent compounds. Both PNP and NTC were metabolized to the corresponding glucuronide and sulfate conjugates. On the other hand, the PNP or NTC glucuronides and sulfates were metabolized with liver microsomes to PNP and NTC.

  18. Stereoselective metabolism of tetrahydropalmatine enantiomers in rat liver microsomes.

    PubMed

    Zhao, Ming; Li, Li-Ping; Sun, Dong-Li; Sun, Si-Yuan; Huang, Shan-Ding; Zeng, Su; Jiang, Hui-Di

    2012-05-01

    Tetrahydropalmatine (THP), with one chiral center, is an active alkaloid ingredient in Rhizoma Corydalis. The aim of the present paper is to study whether THP enantiomers are metabolized stereoselectively in rat, mouse, dog, and monkey liver microsomes, and then, to elucidate which Cytochrome P450 (CYP) isoforms are predominately responsible for the stereoselective metabolism of THP enantiomers in rat liver microsomes (RLM). The results demonstrated that (+)-THP was preferentially metabolized by liver microsomes from rats, mice, dogs, and monkeys, and the intrinsic clearance (Cl(int)) ratios of (+)-THP to (-)-THP were 2.66, 2.85, 4.24, and 1.67, respectively. Compared with the metabolism in untreated RLM, the metabolism of (-)-THP and (+)-THP was significantly increased in dexamethasone (Dex)-induced and β-naphthoflavone (β-NF)-induced RLM; meanwhile, the Cl(int) ratios of (+)-THP to (-)-THP in Dex-induced and β-NF-induced RLM were 5.74 and 0.81, respectively. Ketoconazole had stronger inhibitory effect on (+)-THP than (-)-THP, whereas fluvoxamine had stronger effect on (-)-THP in untreated and Dex-induced or β-NF-induced RLM. The results suggested that THP enantiomers were predominately metabolized by CYP3A1/2 and CYP1A2 in RLM, and CYP3A1/2 preferred to metabolize (+)-THP, whereas CYP1A2 preferred (-)-THP.

  19. Isolation and purification of rat liver morphine UDP-glucuronosyltransferase

    SciTech Connect

    Puig, J.F.; Tephly, T.R.

    1986-03-05

    The enhancement of rat liver microsomal morphine (M) and 4-hydroxybiphenyl (4-HBP) UDP-glucuronyltransferase (UDPGT) activities by phenobarbital treatment has been proposed to represent increased activity of a single enzyme form, GT-2. They have separated M and 4-HBP UDPGT activities from Emulgen 911-solubilized microsomes obtained from livers of phenobarbital-treated Wistar rats. A sensitive assay procedure was developed to quantify M-UDPGT and 4-HBP-UDPGT activities using /sup 14/C-UDP-glucuronic acid (UDPGA) and reversed phase C-18 minicolumns whereby the radioactive glucuronides were differentially eluted from labeled UDPGA. Trisacryl DEAE, and chromatofocusing procedures were employed to separate M-UDPGT and 4-HBP-UDPGT in the presence of exogenous phosphatidylcholine (PC). The PC is necessary to stabilize UDPGT activities. M-UDPGT was isolated to apparent homogeneity and displayed a monomeric molecular weight of 56,000 daltons on SDS-PAGE. It reacted with M but not with 4-HBP, bilirubin, p-nitrophenol, testosterone, androsterone, estrone, 4-aminobiphenyl or ..cap alpha..-naphthylamine. 4-HBP-UDPGT did not react with M. Therefore, M and 4-HBP glucuronidations are catalyzed by separate enzymes in rat liver microsomes.

  20. Isolation and characterization of endosomes from rat liver

    SciTech Connect

    Kennedy, G.C.

    1987-01-01

    Three fractions of rat liver endosomes, called 50 Kg Light, 50 Kg Heavy, and 150 Kg have been isolated on 16% Percoll gradients. The 50 Kg Heavy fraction accumulates ligand as a function of time after injection, using either /sup 125/I-asialoorosomucoid (/sup 125/I-ASOR) or /sup 125/I-immunoglobulin A (/sup 125/I-IgA) as ligands. A pulse-chase protocol was also used to study the kinetics of ligand entry into the endosomal compartments. A double-label, 3,3'-diaminobenzidine (DAB)-induced density shift protocol was used to study the internalization of two ligands with different destinations in the hepatocyte. Rats were injected intraportally with /sup 125/I-ASOR-HRP and /sup 131/I-IgA and the liver was fractionated at various times post-injection. The three ligand-containing endosomal fractions were isolated and each subjected to the DAB shift procedure. This treatment causes organelles containing /sup 125/I-ASOR-HRP and another ligand occupying the same compartment to shift to a higher density. Thus, information on whether the /sup 131/I-IgA is colocalized or segregated from the /sup 125/I-ASOR-HRP can be obtained. The authors have used an instantaneous pulse, temperature shift protocol to study the heterogeneity of these three endosomal fractions isolated from rat liver.

  1. Zonation of glucokinase in rat liver changes during postnatal development.

    PubMed

    Kirchner, G; Harbers, M; Bünsch, A; Seitz, H J; Höppner, W

    1993-08-01

    In the liver many metabolic pathways are preferentially localized in different zones of the acinus. It is assumed that this zonation allows an efficient adaptation to different states of nutrition, because alternative pathways can be regulated independently. It is reported that the rate limiting enzyme for the glycolytic pathway, glucokinase (EC 2.7.1.2), is predominantly located in the pericentral zone. The gene expression of glucokinase is induced to a maximum level after a carbohydrate-rich diet. In starved or diabetic rats glucokinase gene expression is barely detectable. In postnatal development glucokinase is induced to significant levels only from day 14 onwards. The distribution of the glucokinase protein in the rat liver lobule in the first 4 weeks of postnatal life was investigated by immunohistochemistry and compared to the distribution observed in adult rats. In adult rats considerably high levels of glucokinase are measureable as shown by immunoblotting utilizing a monospecific antibody and a photometric assay of glucokinase enzyme activity, respectively. Immunohistochemically the hepatic glucokinase protein is detected in the perivenous area. During postnatal development, the quantities of hepatic glucokinase protein and glucokinase enzyme activity start to increase significantly from day 15 onwards. Subsequently, glucokinase levels rise further until day 29. In contrast to the results obtained by immunoblotting, glucokinase is already detectable in some liver cells in sections from 6-day-old rats by immunohistochemistry. The liver lobule structure at this age is not completely developed, therefore it is not possible to definitely assign these cells to periportal or pericentral areas. At day 10 post partum the number of glucokinase expressing cells, which appear to be localized preferentially in the periportal zone, increases. In agreement with the immunoblotting, an immense increase in glucokinase activity was observed at day 14. The periportal

  2. CHARACTERIZATION OF RAT LIVER SUBCELLULAR MEMBRANES

    PubMed Central

    DeHeer, David H.; Olson, Merle S.; Pinckard, R. Neal

    1974-01-01

    The induction of acute hepatocellular necrosis in rats resulted in the production of complement fixing, IgM autoantibodies directed toward inner and outer mitochondrial membranes, microsomal membrane, lysosomal membrane, nuclear membrane, cytosol, but not to plasma membrane. Utilizing selective absorption procedures it was demonstrated that each subcellular membrane fraction possessed unique autoantigenic activity with little or no cross-reactivity between the various membrane fractions. It is proposed that the development of membrane-specific autoantibodies may provide an immunological marker useful in the differential characterization of various subcellular membranes. PMID:4813214

  3. Transformation and actions of extracellular NADP(+) in the rat liver.

    PubMed

    Broetto-Biazon, Ana Carla; Kangussu, Monica Mendes; Padilha, Fábio; Bracht, Fabrício; Kelmer-Bracht, Ana Maria; Bracht, Adelar

    2008-10-01

    The possible actions and transformation of extracellular NADP(+) in the rat liver have not yet been studied. Considering the various effects of its analogue NAD(+) in the liver, however, effects of NADP(+) can equally be expected. In the present work, this question was approached in the isolated perfused rat liver to get a preliminary picture of the action of extracellular NADP(+) in this organ. NADP(+) (100 microM) produced transient increases in the portal perfusion pressure. Glucose release (glycogenolysis) and lactate production from endogenous glycogen were transiently increased in antegrade and retrograde perfusion. Oxygen uptake was stimulated after a transient inhibition in antegrade perfusion, which was practically absent in retrograde perfusion. Pyruvate production was transiently inhibited. In the absence of Ca(2+), all of these effects were no longer observed. Bromophenacyl bromide, an inhibitor of eicosanoid synthesis, almost abolished all effects. Suramin, a non-specific purinergic P2(YX) antagonist, also inhibited the action of NADP(+). Single pass transformation of 75 microM NADP(+) was equal to 92%. Besides nicotinamide, at least two additional transformation products were detected: 2'-phospho-ADP-ribose and a non-identified component, the former being more important (67% of the transformed NADP(+)). Nicotinic acid adenine dinucleotide phosphate (NAADP) was not found in the outflowing perfusate. It was concluded that NADP(+), like NAD(+), acts on perfusion pressure and glycogen catabolism in the liver mainly via eicosanoid synthesis mediated by purinergic P2(YX) receptors.

  4. Epigenetic changes in the rat livers induced by pyrazinamide treatment

    SciTech Connect

    Kovalenko, V.M.; Bagnyukova, T.V.; Sergienko, O.V.; Bondarenko, L.B.; Shayakhmetova, G.M.; Matvienko, A.V.; Pogribny, I.P.

    2007-12-15

    Drug-induced liver injury, including drug-induced hepatotoxicity during the treatment of tuberculosis infection, is a major health problem with increasingly significant challenges to modern hepatology. Therefore, the assessment and monitoring of the hepatotoxicity of antituberculosis drugs for prevention of liver injury are great concerns during disease treatment. The recently emerged data showing the ability of toxicants, including pharmaceutical agents, to alter cellular epigenetic status, open a unique opportunity for early detection of drug hepatotoxicity. Here we report that treatment of male Wistar rats with antituberculosis drug pyrazinamide at doses of 250, 500 or 1000 mg/kg/day body weight for 45 days leads to an early and sustained decrease in cytosine DNA methylation, progressive hypomethylation of long interspersed nucleotide elements (LINE-1), and aberrant promoter hypermethylation of placental form glutathione-S-transferase (GSTP) and p16{sup INK4A} genes in livers of pyrazinamide-treated rats, while serum levels of bilirubin and activity of aminotransferases changed modestly. The early occurrence of these epigenetic alterations and their association with progression of liver injury specific pathological changes indicate that alterations in DNA methylation may be useful predictive markers for the assessment of drug hepatotoxicity.

  5. Histopathological effects of anthrax lethal factor on rat liver.

    PubMed

    Altunkaynak, Berrin Zuhal; Ozbek, Elvan

    2015-01-01

    Bacillus anthracis, the causative agent of anthrax, has become an increasingly important scientific topic due to its potential role in bioterrorism. The lethal toxin (LT) of B. anthracis consists of lethal factor (LF) and a protective antigen (PA). This study investigated whether only lethal factor was efficient as a hepatotoxin in the absence of the PA. To achieve this aim, LF (100 µg/kg body weight, dissolved in sterile distilled water) or distilled water vehicle were intraperitoneally injected once into adult rats. At 24 h post-injection, the hosts were euthanized and their livers removed and tissue samples examined under light and electron microscopes. As a result of LF application, hepatic injury - including cytoplasmic and nuclear damage in hepatocytes, sinusoidal dilatation, and hepatocellular lysis - became apparent. Further, light microscopic analyses of liver sections from the LF-injected rats revealed ballooning degeneration and cytoplasmic loss within hepatocytes, as well as peri-sinusoidal inflammation. Additionally, an increase in the numbers of Kupffer cells was evident. Common vascular injuries were also found in the liver samples; these injuries caused hypoxia and pathological changes. In addition, some cytoplasmic and nuclear changes were detected within the liver ultrastructure. The results of these studies allow one to suggest that LF could be an effective toxicant alone and that PA might act in situ to modify the effect of this agent (or the reverse situation wherein LF modifies effects of PA) such that lethality results.

  6. Improvement of Liver Cell Therapy in Rats by Dietary Stearic Acid

    PubMed Central

    Goradel, Nasser Hashemi; Eghbal, Mohammad Ali; Darabi, Masoud; Roshangar, Leila; Asadi, Maryam; Zarghami, Nosratollah; Nouri, Mohammad

    2016-01-01

    Background: Stearic acid is known as a potent anti-inflammatory lipid. This fatty acid has profound and diverse effects on liver metabolism. The aim of this study was to investigate the effect of stearic acid on markers of hepatocyte transplantation in rats with acetaminophen (APAP)-induced liver damage. Methods: Wistar rats were randomly assigned to 10-day treatment. Stearic acid was administered to the rats with APAP-induced liver damage. The isolated liver cells were infused intraperitoneally into rats. Blood samples were obtained to evaluate the changes in the serum liver enzymes, including activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) and the level of serum albumin. To assess the engraftment of infused hepatocytes, rats were euthanized, and the liver DNA was used for PCR using sex-determining region Y (SRY) primers. Results: The levels of AST, ALT and ALP in the serum of rats with APAP-induced liver injury were significantly increased and returned to the levels in control group by day six. The APAP-induced decrease in albumin was significantly improved in rats through cell therapy, when compared with that in the APAP-alone treated rats. SRY PCR analysis showed the presence of the transplanted cells in the liver of transplanted rats. Conclusion: Stearic acid-rich diet in combination with cell therapy accelerates the recovering of hepatic dysfunction in a rat model of liver injury. PMID:27090202

  7. Regulation of synthase phosphatase and phosphorylase phosphatase in rat liver.

    PubMed

    Tan, A W; Nuttall, F Q

    1976-08-12

    Using substrates purified from liver, the apparent Km values of synthase phosphatase ([UDPglucose--glycogen glucosyltransferase-D]phosphohydrolase, EC 3.1.3.42) and phosphorylase phosphatase (phosphorylase a phosphohydrolase, EC 3.1.3.17) were found to be 0.7 and 60 units/ml respectively. The maximal velocity of phosphorylase phosphatase was more than a 100 times that of synthase phosphatase. In adrenalectomized, fasted animals there was a complete loss of synthase phosphatase but only a slight decrease in phosphorylase phosphatase when activity was measured using endogenous substrates in a concentrated liver extract. When assayed under optimal conditions with purified substrates, both activities were present but had decreased to very low levels. Mixing experiments indicated that synthase D present in the extract of adrenalectomized fasted animals was altered such that it was no longer a substrate for synthase phosphatase from normal rats. Phosphorylase a substrate on the other hand was unaltered and readily converted. When glucose was given in vivo, no change in percent of synthase in the I form was seen in adrenalectomized rats but the percent of phosphorylase in the a form was reduced. Precipitation of protein from an extract of normal fed rats with ethanol produced a large activation of phosphorylase phosphatase activity with no corresponding increase in synthase phosphatase activity. Despite the low phosphorylase phosphatase present in extracts of adrenalectomized fasted animals, ethanol precipitation increased activity to the same high level as obtained in the normal fed rats. Synthase phosphatase and phosphorylase phosphatase activities were also decreased in normal fasted, diabetic fed and fasted, and adrenalectomized fed rats. Both enzymes recovered in the same manner temporally after oral glucose administration to adrenalectomized, fasted rats. These results suggest an integrated regulatory mechanism for the two phosphatase.

  8. The Dimethylnitrosamine Induced Liver Fibrosis Model in the Rat.

    PubMed

    Chooi, Kum Fai; Kuppan Rajendran, Dinesh Babu; Phang, Siew Siang Gary; Toh, Han Hui Alden

    2016-01-01

    Four to six week old, male Wistar rats were used to produce animal models of liver fibrosis. The process requires four weeks of administration of 10 mg/kg dimethylnitrosamine (DMN), given intraperitoneally for three consecutive days per week. Intraperitoneal injections were performed in the fume hood as DMN is a known hepatoxin and carcinogen. The model has several advantages. Firstly, liver changes can be studied sequentially or at particular stages of interest. Secondly, the stage of liver disease can be monitored by measurement of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzymes. Thirdly, the severity of liver damage at different stages can be confirmed by sacrifice of animals at designated time points, followed by histological examination of Masson's Trichome stained liver tissues. After four weeks of DMN dosing, the typical fibrosis score is 5 to 6 on the Ishak scale. The model can be reproduced consistently and has been widely used to assess the efficacy of potential anti-fibrotic agents. PMID:27340889

  9. Phosphoenolpyruvate carboxykinase and pyruvate carboxylase in developing rat liver

    PubMed Central

    Ballard, F. J.; Hanson, R. W.

    1967-01-01

    1. Phosphoenolpyruvate carboxykinase and pyruvate carboxylase were measured in foetal, newborn and adult rat liver extracts by a radiochemical assay involving the fixation of [14C]bicarbonate. 2. Pyruvate-carboxylase activity in both foetal and adult liver occurs mainly in mitochondrial and nuclear fractions, with about 10% of the activity in the cytoplasm. 3. Similar studies of the intracellular distribution of phosphoenolpyruvate carboxykinase show that more than 90% of the activity is in the cytoplasm. However, in the 17-day foetal liver about 90% of the activity is in mitochondria and nuclei. 4. Pyruvate-carboxylase activity in both particulate and soluble fractions is very low in the 17-day foetal liver and increases to near adult levels before birth. 5. Phosphoenolpyruvate-carboxykinase activity in the soluble cell fraction increases 25-fold in the first 2 days after birth. This same enzyme in the mitochondria has considerable activity in the foetal and adult liver and is lower in the newborn. 6. Kinetic and other studies on the properties of phosphoenolpyruvate carboxykinase have shown no differences between the soluble and mitochondrial enzymes. 7. It is suggested that the appearance of the soluble phosphoenolpyruvate carboxykinase at birth initiates the rapid increase in overall gluconeogenesis at this stage. PMID:6049928

  10. Interstitial photodynamic therapy in a rat liver metastasis model.

    PubMed Central

    van Hillegersberg, R.; Marijnissen, J. P.; Kort, W. J.; Zondervan, P. E.; Terpstra, O. T.; Star, W. M.

    1992-01-01

    Photodynamic therapy (PDT) of hepatic tumours has been restricted owing to the preferential retention of photosensitizers in liver tissue. We therefore investigated interstitial tumour illumination as a means of selective PDT. A piece of colon carcinoma CC531 was implanted in the liver of Wag/Rij rats. Photofrin was administered (5 mg kg-1 i.v.) 2 days before laser illumination. Tumours with a mean (+/- s.e.) diameter of 5.7 +/- 0.1 mm (n = 106, 20 days after implantation) were illuminated with 625 nm light, at 200 mW cm-1 from a 0.5 cm cylindrical diffuser and either 100, 200, 400, 800 or 1600 J cm-1. Control groups received either laser illumination only, Photofrin only or diffuser insertion only. Short-term effects were studied on the second day after illumination by light microscopy and computer-assisted integration of the circumference of damaged areas. Long-term effects were studied on day 36. To determine the biochemistry of liver damage and function, serum ASAT and ALAT levels were measured on day 1 and 2, and antipyrine clearance on day 1. Tumour and surrounding liver necrosis increased with light dose delivered (P < 0.001). Best long-term results were obtained at 800 J cm-1 with complete tumour remission in 4 out of 6 animals. No deterioration in liver function was found. The results of this study show the ability of interstitial PDT to cause major destruction of tumour tissue in the liver combined with minimal liver damage. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:1457339

  11. Characterization of chylomicron remnant binding to rat liver membranes.

    PubMed

    Cooper, A D; Erickson, S K; Nutik, R; Shrewsbury, M A

    1982-01-01

    The binding of chylomicron remnants to rat liver membranes was investigated using radioiodinated lipoproteins. The specific activity of binding increased in parallel with increased enrichment in plasma membrane markers. The yield of receptor activity, however, decreased with enrichment. Accordingly, a partially purified plasma membrane preparation was used for routine studies. Binding was saturable, with half maximal binding achieved at 4.6 micro g tetramethylurea-precipitable protein per ml. The rate of binding was time- and temperature-dependent. It could be inhibited only moderately by 10 mM EDTA. Chylomicron remnants appeared to bind to the membrane as a unit. The bound particle was richer in apoproteins of 20,000-50,000 molecular weight relative to low molecular weight apoproteins than the particles that were not bound. Lipoprotein particles containing only human apoB did not bind to liver membranes nor did they compete for the remnant binding site. Rat lipoproteins of d 1.019-1.063 g/ml did compete for remnant binding. When they were separated into apoB-rich (LDL) or apoE-rich (HDL(c)) fractions by block electrophoresis, the apoE-rich fraction was a more potent competitor. ApoE purified and reconstituted into dimyristoyl phosphatidylcholine vesicles was a potent competitor for the remnant binding site. Vesicles containing (125)I-labeled apoE bound to the membranes, and they could be displaced by unlabeled remnants. Dimyristoyl phosphatidylcholine vesicles themselves did not compete with either remnants or apoE-phospholipid vesicles. These results offer strong support for the hypothesis that the liver membrane chylomicron remnant receptor recognizes apoE with a high affinity, and this initiates the rapid removal of lipoproteins that contain this apoprotein.-Cooper, A. D., S. K. Erickson, R. Nutik, and M. A. Shrewsbury. Characterization of chylomicron remnant binding to rat liver membranes.

  12. Enantiomeric composition of the trans-dihydrodiols produced from phenanthrene by fungi

    SciTech Connect

    Sutherland, J.B.; Fu, P.P.; Von Tungeln, L.S.; Cerniglia, C.E. ); Yang, S.K. ); Casillas, R.P.; Crow, S.A. )

    1993-07-01

    Phenanthrene and other polycyclic aromatic hydrocarbons (PAHs) are widespread environmental pollutants. PAHs are frequently bioaccumulated by animals and can be activated to mutagenic and carcinogenic metabolites, but they are resistant to biodegradation by microorganisms. Although PAHs do not generally serve as carbon or energy sources for fungi, many fungi cometabolize one or more PAHs to trans-dihydrodiols. In this study, circular dichroism spectroscopy and chiral stationary-phase high-performance liquid chromatography is used to compare the stereoselectivity of three species of fungi that metabolize phenanthrene to trans-dihydrodiols, Cunninghamella elegans, Syncephalastrum racemosum, and Phanerochaete chrysosporium. 30 refs., 5 figs., 1 tab.

  13. Differential Sympathetic Vasomotor Activation Induced by Liver Cirrhosis in Rats

    PubMed Central

    Bergamaschi, Cássia T.; Campos, Ruy R.

    2016-01-01

    We tested the hypothesis that there is a topographical sympathetic activation in rats submitted to experimental cirrhosis. Baseline renal (rSNA) and splanchnic (sSNA) sympathetic nerve activities were evaluated in anesthetized rats. In addition, we evaluated main arterial pressure (MAP), heart rate (HR), and baroreceptor reflex sensitivity (BRS). Cirrhotic Wistar rats were obtained by bile duct ligation (BDL). MAP and HR were measured in conscious rats, and cardiac BRS was assessed by changes in blood pressure induced by increasing doses of phenylephrine or sodium nitroprusside. The BRS and baseline for the control of sSNA and rSNA were also evaluated in urethane-anesthetized rats. Cirrhotic rats had increased baseline sSNA (BDL, 102 vs control, 58 spikes/s; p<0.05), but no baseline changes in the rSNA compared to controls. These data were accompanied by increased splanchnic BRS (p<0.05) and decreased cardiac (p<0.05) and renal BRS (p<0.05). Furthermore, BDL rats had reduced basal MAP (BDL, 93 vs control, 101 mmHg; p<0.05) accompanied by increased HR (BDL, 378 vs control, 356; p<0.05). Our data have shown topographical sympathetic activation in rats submitted to experimental cirrhosis. The BDL group had increased baseline sSNA, independent of dysfunction in the BRS and no changes in baseline rSNA. However, an impairment of rSNA and HR control by arterial baroreceptor was noted. We suggest that arterial baroreceptor impairment of rSNA and HR is an early marker of cardiovascular dysfunction related to liver cirrhosis and probably a major mechanism leading to sympathoexcitation in decompensated phase. PMID:27055088

  14. Postnatal changes in sialylation of glycoproteins in rat liver.

    PubMed Central

    Oda-Tamai, S; Kato, S; Akamatsu, N

    1991-01-01

    Glycoproteins containing N-linked oligosaccharides were prepared from plasma and liver microsomes of rats aged 0-5 weeks, and galactose and sialic acid content were determined. The sialic acid/galactose ratios in plasma membrane N-glycans remained at about 1 throughout the postnatal period, suggesting that most of the galactose residues are sialylated. In the same way, it was suggested that most of the galactose residues of microsomal N-glycans were sialylated at 0, 4 and 5 weeks of age, but that the degree of sialylation was lower at the other ages, with a minimum at 2 weeks. When the activities of sialyltransferase and galactosyltransferase in liver Golgi membranes were determined, age-dependent changes were found, not only in the specific activities of the enzymes, but also in the Golgi membrane content per g of liver. The activity of galactosyltransferase per g of liver increased immediately after birth, whereas that of sialyltransferase remained at a low level for 2 weeks and then increased to a constant level at 4 weeks. It is probable that this delayed increase in the activity of sialyltransferase results in the decreased sialylation of microsomal N-glycans at 1, 2 and 3 weeks. Sialyltransferase was solubilized from the liver microsomes of rats aged 2, 3 and 4 weeks and characterized. Phosphocellulose column chromatography separated the activity into two subfractions, designated transferase I and transferase II in the order of elution. The increase in total sialyltransferase activity during this period was caused mainly by an increase in transferase I. Rechromatography of each transferase from 3-week-old rats after neuraminidase treatment showed that transferase I but not transferase II contained sialic acid residue(s) and that desialylated transferase I was eluted in a similar way as transferase II. Although the apparent Km value for CMP-N-acetylneuraminic acid and the heat stability of transferase I were different from those of transferase II, the

  15. Accumulation of D-arginine by rat liver mitochondria.

    PubMed

    Villalobos-Molina, R; Pardo, J P; Saavedra-Molina, A; Piña, E

    1987-12-01

    The permeability of the inner mitochondrial membrane from rat liver to D-arginine was studied. By using safranin as a probe of the membrane potential, depolarization of energized liver mitochondria occurred in a dose-dependent fashion starting at 3.3 mmol/L of D- or DL-arginine. When ethidium bromide fluorescence was employed, a decrease in the membrane potential due to D- or DL-arginine was observed. A parallel significant change in succinate-induced respiration in rat liver mitochondria was found in response to osmotic swelling in 125 mmol/L of D-arginine salts. L-Arginine, L-glutamine, L-asparagine, L-ornithine, D-ornithine, and L-lysine did not modify the membrane potential at the concentrations tested. D-Arginine was not transformed into citrulline, but 1.0 mmol/L of the D-amino acid inhibited, by 42%, the state 3 of mitochondrial respiration using succinate as substrate. When D-arginine was used in combination with nigericin, a 40% inhibition of mitochondrial respiration in state 3 was recorded with succinate and with glutamate-malate as substrates. PMID:3454185

  16. Quantitation of multistage carcinogenesis in rat liver.

    PubMed

    Pitot, H C; Dragan, Y P; Teeguarden, J; Hsia, S; Campbell, H

    1996-01-01

    A well characterized model of multistage carcinogenesis is that of hepatocarcinogenesis in the rat. The histopathology as well as the cell and molecular biology of the stages of initiation, promotion, and progression have been elucidated to varying degrees in this system. Putatively single initiated hepatocytes are identified by their expression of the ubiquitous marker of hepatocarcinogenesis, glutathione-S-transferase pi (GSTP). 0.5-1.0 x 10(6) GSTP-positive "initiated" hepatocytes developed within 14 days after initiation with a subcarcinogenic dose of diethylnitrosamine (DEN). Approximately 1% of these cells develop clonally into altered hepatic foci (AHF) in animals administered promoting agents, such as phenobarbital, chronically for 4-8 mo. Hepatocytes within AHF during the stage of promotion exhibit normal diploid karyotypes but various phenotypes depending on the chemical nature of the promoting agent. Continued administration of the promoting agent results in the infrequent development of hepatocellular carcinomas; however, administration of a complete carcinogen or a progressor agent during the stage of promotion results in substantial numbers of hepatic neoplasms. In order to quantitate the development of the stage of progression more accurately, markers selective for this stage have been sought. Transforming growth factor-alpha (TGF-alpha) appears to be such a marker of progression. About 500 TGF-alpha-positive lesions develop spontaneously following initiation and continued promotion, usually within GSTP-positive AHF, but administration of a single dose of a progressor agent such as ethylnitrosourea may increase this number 3-fold or more. Some agents such as gamma radiation and hydroxyurea, when administered as single or a few closely spaced multiple doses, result in no increased number in TGF-alpha-positive lesions but a markedly enhanced increase in their growth rate. By monitoring gene expression using quantitative stereology, the stages of

  17. Prilocaine elimination by isolated perfused rat lung and liver.

    PubMed

    Geng, W P; Ebke, M; Foth, H

    1995-01-01

    Prilocaine is assumed to undergo significant elimination by extrahepatic organs and to differ in this respect from other commonly used local anaesthetics. In order to clarify whether the lung may play an important role as a site of elimination of prilocaine, the kinetic parameters were studied in isolated perfused rat lungs and were compared to those of isolated livers. Furthermore, the structurally related compounds bupivacaine and mepivacaine were also investigated in this system. Prilocaine was dispersed into a relatively large apparent distribution volume in perfused rat lung (139 ml versus 97 ml in controls). In single-pass perfused lungs the observed maximum of concentration was decreased by about 60% compared to controls. The mean residence time was prolonged by about 40%. These observations suggest that prilocaine is substantially retained by rat lung and that this effect occurs particularly during first-pass. However, the ability of rat lung to degrade prilocaine was relatively low. The clearance values were about 0.3 ml/min equal to about 20% of the hepatic capacity calculated per g of tissue. Thus it must be assumed that prilocaine is only transiently retained by the lung and will gain systemic availability later on. In rat lungs the kinetics of prilocaine elimination were not substantially different from those of bupivacaine and mepivacaine (16 and 12%). These observations do not support the assumption that especially prilocaine undergoes extrahepatic elimination.

  18. Computer image analysis of toxic fatty degeneration in rat liver.

    PubMed

    Stetkiewicz, J; Zieliński, K; Stetkiewicz, I; Koktysz, R

    1989-01-01

    Fatty degeneration of the liver is one of the most frequently observed pathological changes in the experimental estimation of the toxicity of chemical compounds. The intensity of this kind of damage is most often detected by means of a generally accepted scale of points, whereas the classification is performed according to the subjective "feeling" of the pathologist. In modern pathological diagnostics, computer analysis of images is used to perform an objective estimation of the degree of damage to various organs. In order to check the usefulness of this kind of method, comparative biochemical and morphometrical studies were undertaken in trichloroethylene (TRI)-induced fatty degeneration of the liver. TRI was administered to rats intragastrically, in single doses: 1/2; 1/3; 1/4; 1/6 and 1/18 DL50. 24 hours after the administration, the animals were sacrificed. The content of triglycerides in the liver was determined according to Folch et al. (1956). Simple lipids in the histochemical samples were detected by means of staining with a lipotropic, Fat Red 7B. The area of fatty degeneration was estimated in the microscopic samples by the use of an automatic image analyser IBAS 2000 (Kontron). The morphometrical data concerning the area of fatty degeneration in the liver amplified a high degree of correlation with the content of triglycerides (r = 0.89) and the dose of TRI (r = 0.96). The degree of correlation between the biochemical data and the dose of TRI was 0.88. The morphometrical studies performed have proved to be of great use in estimating the degree of fatty degeneration in the liver. This method enables precise, quantitative measuring of this sort of liver damage in the material prepared for routine histopathological analysis. It requires, however, the application of a specialized device for quantitative image analysis.

  19. Hepatoprotective Activity of Heptoplus on Isoniazid and Rifampicin Induced Liver Damage in Rats

    PubMed Central

    Sankar, M.; Rajkumar, Johanna; Sridhar, Dorai

    2015-01-01

    The present study is designed to evaluate the efficacy of heptoplus a polyherbal formulation as an oral supplementary agent for isoniazid and rifampicin induced hepatotoxicity in rats. 50 and 100 mg/kg of heptoplus supplement were fed orally to the rats along with isoniazid and rifampicin and compared to rats treated with 100 mg/kg Liv 52 standard drug. Rats treated with isoniazid and rifampicin suffered from severe oxidative stress by the virtue of free radicals induced lipid per oxidation. As a result abnormal index of serum biochemical markers for liver function and increased liver lysosomal enzymes activity was observed. However rats nourished with 100 mg/kg of heptoplus and Liv 52 protected the liver from oxidative damage by maintaining normal antioxidant profile status and restored normal serum liver biochemical markers. Increased liver lysosomal enzymes activity is prevented in the rats supplemented with heptoplus and Liv 52. Histopathological analysis also revealed severe vascular changes and lobular necrosis in the treatment of isoniazid and rifampicin. Heptoplus (100 mg/kg) and Liv 52 supplemented rats liver apparently revealed normal architecture of liver. This study confirms that heptoplus has liver protective activity against Isoniazid and Rifampicin induced liver injury in rats, in par with Liv 52. PMID:26798170

  20. Deiodination of thyroid hormones by the perfused rat liver

    PubMed Central

    Hillier, A. P.

    1972-01-01

    1. An investigation has been made into the deiodination of thyroid hormones by the perfused rat liver. The hormones were labelled with 125I in the phenolic ring and the rate of deiodination was estimated by measuring the release of radio-iodide into the perfusate. 2. At tracer concentrations, 0·98% of the liver thyroxine is deiodinated/5 min. The deiodination of tri-iodothyronine is considerably faster, 3·3%/5 min. 3. Deiodination is very sensitive to changes in temperature. 4. The reaction shows saturation kinetics typical of many enzymes, the reciprocal of the rate of deiodination being proportional to the reciprocal of the hormone concentration in the tissue. The maximum rate of deiodination of each hormone is about 1·5 μg/min for a whole liver preparation weighing 16 g. 5. Tri-iodothyronine inhibits thyroxine deiodination and vice versa, suggesting that a single enzyme is responsible for both reactions. 6. Propyl thiouracil (PTU) at high concentrations inhibits the deiodination of both hormones. 7. An abnormally high rate of deiodination is associated with the actual injection of hormone into the preparation. This suggests that only the free (unbound) hormone in the tissue is directly available to the deiodinating enzyme. 8. About half of the whole body deiodination of thyroxine is relatively insensitive to PTU. It is suggested that most of this type of deiodination is performed in the liver and that the process is one of inactivation. PMID:5033472

  1. Purification and characterization of paraoxon hydrolase from rat liver.

    PubMed Central

    Rodrigo, L; Gil, F; Hernandez, A F; Marina, A; Vazquez, J; Pla, A

    1997-01-01

    Paraoxonase (paraoxon hydrolase), an enzyme that hydrolyses paraoxon (O,O-diethyl O-p-nitrophenyl phosphate), is located in mammals primarily in the serum and liver. Although considerable information is available regarding serum paraoxonase, little is known about the hepatic form of this enzyme. The present work represents the first study on the purification of rat liver paraoxonase. This enzyme has been purified 415-fold to apparent homogeneity with a final specific activity of 1370 units/mg using a protocol consisting of five steps: solubilization of the microsomal fraction, hydroxyapatite adsorption, chromatography on DEAE-Sepharose CL-6B, non-specific affinity chromatography on Cibacron Blue 3GA and anion exchange on Mono Q HR 5/5. The presence of Ca2+ and Triton X-100 in the buffers throughout the purification procedure was essential for maintaining enzyme activity. SDS/PAGE of the final preparation indicated a single protein-staining band with an apparent Mr of 45 000. N-terminal and internal amino acid sequences were determined and compared with those of paraoxonases from human and rabbit serum and mouse liver, showing a high similarity. The pH profile showed optimum activity at pH 8.5. The pH stability and heat inactivation of the enzyme were also studied. The Km for liver paraoxonase was 1.69 mM. PMID:9032442

  2. Sexual dimorphic expression of ADH in rat liver: importance of the hypothalamic-pituitary-liver axis.

    PubMed

    Simon, Francis R; Fortune, John; Iwahashi, Mieko; Sutherland, Eileen

    2002-09-01

    Hepatic alcohol dehydrogenase (ADH) activity is higher in female than in male rats. Although sex steroids, thyroid, and growth hormone (GH) have been shown to regulate hepatic ADH, the mechanism(s) for sexual dimorphic expression is unclear. We tested the possibility that the GH secretory pattern determined differential expression of ADH. Gonadectomized and hypophysectomized male and female rats were examined. Hepatic ADH activity was 2.1-fold greater in females. Because protein and mRNA content were also 1.7- and 2.4-fold greater, results indicated that activity differences were due to pretranslational mechanisms. Estradiol increased ADH selectively in males, and testosterone selectively decreased activity and mRNA levels in females. Effect of sex steroids on ADH was lost after hypophysectomy; infusion of GH in males increased ADH to basal female levels, supporting a role of the pituitary-liver axis. However, GH and L-thyroxine (T4) replacements alone in hypophysectomized rats did not restore dimorphic differences for either ADH activity or mRNA levels. On the other hand, T4 in combination with intermittent administration of GH reduced ADH activity and mRNA to basal male values, whereas T4 plus GH infusion replicated female levels. These results indicate that the intermittent male pattern of GH secretion combined with T4 is the principal determinant of low ADH activity in male liver.

  3. Glycyrrhetinic acid-induced permeability transition in rat liver mitochondria.

    PubMed

    Salvi, Mauro; Fiore, Cristina; Armanini, Decio; Toninello, Antonio

    2003-12-15

    Glycyrrhetinic acid, a hydrolysis product of one of the main constituents of licorice, the triterpene glycoside of glycyrrhizic acid, when added to rat liver mitochondria at micromolar concentrations induces swelling, loss of membrane potential, pyridine nucleotide oxidation, and release of cytochrome c and apoptosis inducing factor. These changes are Ca(2+) dependent and are prevented by cyclosporin A, bongkrekic acid, and N-ethylmaleimide. All these observations indicate that glycyrrhetinic acid is a potent inducer of mitochondrial permeability transition and can trigger the pro-apoptotic pathway. PMID:14637195

  4. Interaction of sulfur mustard with rat liver salt fractionated chromatin.

    PubMed

    Jafari, Mahvash; Nateghi, M; Rabbani, A

    2010-01-01

    In this study, the interaction of an alkylating agent, sulfur mustard (SM) with rat liver active (S1 and S2) and inactive (P2) chromatin was investigated employing UV/vis spectroscopy and gel electrophoreses. The results show that SM affects the chromatin structure in a dose-dependent manner. The binding of SM to fractions is different. At lower concentrations (<500 microM), SM seems to unfold the structure and at higher concentrations, it induces aggregation and condensation of chromatin possibly via forming cross-links between the chromatin components. The extent of condensation in S2 is higher when compared to the P2 fraction.

  5. Purification and photoaffinity labelling of lipid methyltransferase from rat liver.

    PubMed Central

    Pajares, M A; Alemany, S; Varela, I; Marin Cao, D; Mato, J M

    1984-01-01

    An enzyme that catalyses the three-step methylation of phosphatidylethanolamine to phosphatidylcholine as well as the methylation of fatty acids and that uses S-adenosylmethionine as the methyl donor has been purified about 200-fold from rat liver. Irradiation of the purified enzyme with a short-wavelength u.v. light in the presence of [methyl-3H]8-azido-S-adenosylmethionine followed by electrophoresis results in the incorporation of radioactivity into a single protein band of about 25 kDa. It is concluded that a single catalytic subunit catalyses the conversion of phosphatidylethanolamine into phosphatidylcholine and fatty acid methylation. Images Fig. 4. PMID:6497846

  6. Liver tumor promoting effects of fenbendazole in rats.

    PubMed

    Shoda, T; Onodera, H; Takeda, M; Uneyama, C; Imazawa, T; Takegawa, K; Yasuhara, K; Watanabe, T; Hirose, M; Mitsumori, K

    1999-01-01

    In order to examine whether fenbendazole has tumor-promoting activity, a total of 70 male Fischer 344 rats were initiated with a single intraperitoneal injection of 100 mg/kg of diethylnitrosamine (DEN) or were given the saline vehicle alone; beginning 1 wk later, rats were given a diet containing 3,600; 1,800; 600; 200; 70; or 0 ppm of fenbendazole for 8 wk. Subgroups of 5 rats each from the DEN+ 1,800; DEN+0; 1,800; and 0 ppm groups were euthanatized after 1 wk of fenbendazole treatment, and the remaining animals were euthanatized at 8 wk. After 1 wk, relative liver weights (ratios to body weights) were significantly increased in the DEN+ 1,800 and 1,800 ppm groups, and based on light microscopy, periportal hepatocellular hypertrophy was evident in these groups. After 8 wk, relative liver weights were significantly increased in the groups given > or =600 ppm with or without DEN initiation. Periportal hepatocellular hypertrophy, characterized by a marked increase in smooth endoplasmic reticulum, was observed in the groups given > or =600 ppm with or without DEN initiation. Induction of cytochrome P-450 (CYP) 1A2, 2B1, or 4A1 was noted in the fenbendazole-treated groups with or without DEN initiation; that associated with CYP 1A2 was most marked. Positive immunostaining for anti-CYP 1A1/2 or CYP 2B1/2 was observed diffusely in the livers of animals in the DEN+1,800 and DEN+3,600 ppm groups. The numbers and areas of connexin 32 (Cx32)-positive spots per square centimeter in centrilobular hepatocytes were significantly decreased in an almost dose-dependent manner with fenbendazole treatment after DEN initiation. In situ hybridization for Cx32 mRNA revealed a remarkable decrease in its expression in the centrilobular hepatocytes in the DEN+70 ppm group. The numbers of glutathione S-transferase placental-form positive single cells (plus mini foci) were significantly increased in the DEN+ 1,800 and DEN+3,600 ppm groups. Since those agents that induce CYP 2B1/2 isozymes

  7. Biochemical effects of three carcinogenic chlorinated methanes in rat liver

    SciTech Connect

    Kitchin, K.T.; Brown, J.L.

    1989-01-01

    Three chlorinated methanes, carbon tetrachloride, chloroform and methylene chloride known to cause liver tumors in rodents, were given by oral gavage to adult female rats both 21 and 4 hours before sacrifice. Then hepatic DNA damage, ornithine decarboxylase, cytochrome P-450, glutathione content and serum alanine aminotransferase activity assays were performed. Carbon tetrachloride increased rat hepatic ornithine decarboxylase activity and decreased cytochrome P-450 content at doses both below and above cytotoxicity (as measured by increased serum alanine aminotransferase activity). At 54 and 160 mg/kg, chloroform increased hepatic ornithine decarboxylase activity with minimal or no elevation in serum alanine aminotransferase activity. After oral administration of 480 mg/kg of chloroform, hepatic ornithine decarboxylase activity, serum alanine aminotransferase activity and hepatic DNA damage were increased while hepatic cytochrome P-450 content was decreased. The results with methylene chloride varied between replicates done on three different days.

  8. Mistletoe alkali inhibits peroxidation in rat liver and kidney

    PubMed Central

    Shi, Zheng-Ming; Feng, Ping; Jiang, Dong-Qiao; Wang, Xue-Jiang

    2006-01-01

    AIM: To explore the antioxidant and free radical scavenger properties of mistletoe alkali (MA). METHODS: The antioxidant effect of mistletoe alkali on the oxidative stress induced by carbon tetrachloride (CCl4) in rats was investigated. The rats were divided into four groups (n = 8): CCl4-treated group (1 mL/kg body weight), MA -treated group (90 mg/kg), CCl4+MA-treated group and normal control group. After 4 wk of treatment, the level of malondialdehyde (MDA), a lipid peroxidation product (LPO) was measured in serum and homogenates of liver and kidney. Also, the level of glutathione (GSH), and activities of glutathione reductase (GR), glutathione peroxidase (GSPx), superoxide dismutase (SOD), and glutathione-S-transferase (GST) in liver and kidney were determined. Scavenging effects on hydroxyl free radicals produced in vitro by Fenton reaction were studied by ESR methods using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a spin trap reagent and H2O2/UV as the OH· source. Urinary 8-hydroxydeoxyguanosine (8-OHdG) was determined by competitive ELISA. RESULTS: In CCl4-treated group, the level of LPO in serum of liver and kidney was significantly increased compared to controls. The levels of GSH and enzyme activities of SOD, GSPx and GR in liver and kidney were significantly decreased in comparison with controls. In CCl4+MA-treated group, the changes in the levels of LPO in serum of liver and kidney were not statistically significant compared to controls. The levels of SOD, GSPx and GR in liver and kidney were significantly increased in comparison with controls. There was a significant difference in urinary excretion of 8-OHdG between the CCl4-treated and MA-treated groups. CONCLUSION: Oxidative stress may be a major mechanism for the toxicity of CCl4. MA has a protective effect against CCl4 toxicity by inhibiting the oxidative damage and stimulating GST activities. Thus, clinical application of MA should be considered in cases with carbon tetrachloride-induced injury

  9. Reduction of 7-ketolithocholic acid to chenodeoxycholic acid by rat liver preparations in vitro.

    PubMed

    Amuro, Y; Yamade, W; Nakano, T; Hayashi, E; Hada, T; Higashino, K

    1985-08-16

    The formation of chenodeoxycholic acid via 7-ketolithocholic acid by rat liver preparations was examined in vitro. Results showed that a rat liver preparation reduced 7-ketolithocholic acid mainly to chenodeoxycholic acid and to ursodeoxycholic acid in a smaller amount, and that the reductase required NADPH but not NADH as coenzyme and was mainly localized in the microsomes. PMID:4016150

  10. Noninvasive Blood Perfusion Measurements of an Isolated Rat Liver and an Anesthetized Rat Kidney

    PubMed Central

    Mudaliar, Ashvinikumar V.; Ellis, Brent E.; Ricketts, Patricia L.; Lanz, Otto I.; Lee, Charles Y.; Diller, Thomas E.; Scott, Elaine P.

    2008-01-01

    A simple, cost effective, and noninvasive blood perfusion system is tested in animal models. The system uses a small sensor to measure the heat transfer response to a thermal event (convective cooling) imposed on the tissue surface. Heat flux data are compared with a mathematical model of the tissue to estimate both blood perfusion and thermal contact resistance between the tissue and the probe. The perfusion system was evaluated for repeatability and sensitivity using isolated rat liver and exposed rat kidney tests. Perfusion in the isolated liver tests was varied by controlling the flow of the perfusate into the liver, and the perfusion in the exposed kidney tests was varied by temporarily occluding blood flow through the renal artery and vein. The perfusion estimated by the convective perfusion probe was in good agreement with that of the metered flow of the perfusate into the liver model. The liver tests indicated that the probe can be used to detect small changes in perfusion (0.005 ml/ml/s). The probe qualitatively tracked the changes in the perfusion in the kidney model due to occlusion of the renal artery and vein. PMID:19045542

  11. Resveratrol inhibits nonalcoholic fatty liver disease in rats

    PubMed Central

    Bujanda, Luis; Hijona, Elizabeth; Larzabal, Mikel; Beraza, Marta; Aldazabal, Pablo; García-Urkia, Nerea; Sarasqueta, Cristina; Cosme, Angel; Irastorza, Belen; González, Alberto; Arenas, Juan I

    2008-01-01

    Background The prevalence of nonalcoholic fatty liver disease (NAFLD) is high. NAFLD is linked to obesity, diabetes mellitus, and hypertriglyceridemia. Approximately 20% of patients with NAFLD will eventually develop cirrhosis. Our purpose was to investigate whether resveratrol decreased hepatic steatosis in an animal model of steatosis, and whether this therapeutic approach resulted in a decrease in tumor necrosis factor α (TNF-α) production, lipid peroxidation and oxidative stress. Methods Male Wistar CRL: Wi (Han) (225 g) rats were randomized into three groups. A control group (n = 12) was given free access to regular dry rat chow for 4 weeks. The steatosis (n = 12) and resveratrol (n = 12) groups were given free access to feed (a high carbohydrate-fat free modified diet) and water 4 days per week, and fasted for the remaining 3 days for 4 weeks. Rats in the resveratrol group were given resveratrol 10 mg daily by the oral route. All rats were killed at 4 weeks and assessed for fatty infiltration and bacterial translocation. Levels of TNF-α in serum, hepatic malondialdehyde (MDA), oxidative stress (superoxide dismutase, glutathione peroxidase, catalase and nitric oxide synthase) and biochemical parameters were measured. Results Fat deposition was decreased in the resveratrol group as compared to the steatosis group (Grade 1 vs Grade 3, P < 0.05). TNF-α and MDA levels were significantly increased in the steatosis group (TNF-α; 33.4 ± 5.2 vs 26.24 ± 3.47 pg/ml and MDA; 9.08 ± 0.8 vs 3.17 ± 1.45 μM respectively, P < 0.05). This was accompanied by increased superoxide dismutase, glutathione peroxidase and catalase and decreased nitric oxide synthase in the liver of resveratrol group significantly (P < 0.05 vs steatosis group). Bacterial translocation was not found in any of the groups. Glucose levels were decreased in the group of rats given resveratrol (P < 0.05). Conclusion Resveratrol decreased NAFLD severity in rats. This effect was mediated, at least

  12. The biosynthesis of glycerides by mitochondria from rat liver

    PubMed Central

    Smith, Margaret E.; Hübscher, G.

    1966-01-01

    1. The synthesis of glycerides from l-3-glycerophosphate and palmitic acid by mitochondrial preparations from rat liver was shown to be stimulated markedly by a soluble factor from the supernatant fraction of the liver. 2. That the soluble factor was a protein was indicated by its inactivation after treatment with papain and after boiling for 3min. at 100°, its precipitation by ammonium sulphate and its behaviour on Sephadex G-200. The soluble factor was purified by ammonium sulphate fractionation and gel filtration. 3. Bovine serum albumin and lipoprotein fractions from rat and human serum also stimulated glyceride biosynthesis but the stimulations were one-twentieth to one-third of that obtained with the soluble factor. 4. The function of the soluble factor could not be explained by assuming a leakage of acyl-CoA synthetase, phosphatidate phosphatase or diglyceride acyltransferase from the mitochondria into the supernatant during preparation of the mitochondrial fraction. 5. Palmitic acid, in the presence of the soluble factor and optimum amounts of ATP and CoA, was a more effective substrate than palmitoyl-CoA or palmitoylcarnitine for the biosynthesis of glycerides by mitochondria. PMID:4290720

  13. Purification of phospholipid methyltransferase from rat liver microsomal fraction.

    PubMed Central

    Pajares, M A; Villalba, M; Mato, J M

    1986-01-01

    Phospholipid methyltransferase, the enzyme that converts phosphatidylethanolamine into phosphatidylcholine with S-adenosyl-L-methionine as the methyl donor, was purified to apparent homogeneity from rat liver microsomal fraction. When analysed by SDS/polyacrylamide-gel electrophoresis only one protein, with molecular mass about 50 kDa, is detected. This protein could be phosphorylated at a single site by incubation with [alpha-32P]ATP and the catalytic subunit of cyclic AMP-dependent protein kinase. A less-purified preparation of the enzyme is mainly composed of two proteins, with molecular masses about 50 kDa and 25 kDa, the 50 kDa form being phosphorylated at the same site as the homogeneous enzyme. After purification of both proteins by electro-elution, the 25 kDa protein forms a dimer and migrates on SDS/polyacrylamide-gel electrophoresis with molecular mass about 50 kDa. Peptide maps of purified 25 kDa and 50 kDa proteins are identical, indicating that both proteins are formed by the same polypeptide chain(s). It is concluded that rat liver phospholipid methyltransferase can exist in two forms, as a monomer of 25 kDa and as a dimer of 50 kDa. The dimer can be phosphorylated by cyclic AMP-dependent protein kinase. Images Fig. 3. Fig. 4. Fig. 6. PMID:3800912

  14. Ethynylestradiol increases expression and activity of rat liver MRP3.

    PubMed

    Ruiz, María L; Villanueva, Silvina S M; Luquita, Marcelo G; Vore, Mary; Mottino, Aldo D; Catania, Viviana A

    2006-06-01

    We evaluated the effect of ethynylestradiol (EE) administration (5 mg/kg b.wt. s.c., for 5 consecutive days) on the expression and activity of multidrug resistance-associated protein 3 (Mrp3) in rats. Western blotting analysis revealed decreased Mrp2 (-41%) and increased Mrp3 (+200%) expression by EE. To determine the functional impact of up-regulation of Mrp3 versus Mrp2, we measured the excretion of acetaminophen glucuronide (APAP-glu), a common substrate for both transporters, into bile and perfusate in the recirculating isolated perfused liver (IPL) model. APAP-glu was generated endogenously from acetaminophen (APAP), which was administered as a tracer dose (2 micromol/ml) into the perfusate. Biliary excretion of APAP-glu after 60 min of perfusion was reduced in EE-treated rats (-80%). In contrast, excretion into the perfusate was increased by EE (+45%). Liver content of APAP-glu at the end of the experiment was reduced by 36% in the EE group. The total amount of glucuronide remained the same in both groups. Taken together, these results indicate that up-regulation of Mrp3 led to an exacerbated basolateral versus canalicular excretion of conjugated APAP in IPL. We conclude that induced expression of basolateral Mrp3 by EE may represent a compensatory mechanism to prevent intracellular accumulation of common Mrp substrates, either endogenous or exogenous, due to reduced expression and activity of apical Mrp2. PMID:16554369

  15. Effective Prevention of Liver Fibrosis by Liver-targeted Hydrodynamic Gene Delivery of Matrix Metalloproteinase-13 in a Rat Liver Fibrosis Model

    PubMed Central

    Abe, Hiroyuki; Kamimura, Kenya; Kobayashi, Yuji; Ohtsuka, Masato; Miura, Hiromi; Ohashi, Riuko; Yokoo, Takeshi; Kanefuji, Tsutomu; Suda, Takeshi; Tsuchida, Masanori; Aoyagi, Yutaka; Zhang, Guisheng; Liu, Dexi; Terai, Shuji

    2016-01-01

    Liver fibrosis is the final stage of liver diseases that lead to liver failure and cancer. While various diagnostic methods, including the use of serum marker, have been established, no standard therapy has been developed. The objective of this study was to assess the approach of overexpressing matrix metalloproteinase-13 gene (MMP13) in rat liver to prevent liver fibrosis progression. A rat liver fibrosis model was established by ligating the bile duct, followed by liver-targeted hydrodynamic gene delivery of a MMP13 expression vector, containing a CAG promoter-MMP13-IRES-tdTomato-polyA cassette. After 14 days, the serum level of MMP13 peaked at 71.7 pg/ml in MMP13-treated group, whereas the nontreated group only showed a level of ~5 pg/ml (P < 0.001). These levels were sustained for the next 60 days. The statistically lower level of the hyaluronic acids in treated group versus the nontreated group (P < 0.05) reveals the therapeutic effect of MMP13 overexpression. Quantitative analysis of tissue stained with sirius red showed a statistically larger volume of fibrotic tissue in the nontreated group compared to that of MMP13-treated rats (P < 0.05). These results suggest that the liver-targeted hydrodynamic delivery of MMP13 gene could be effective in the prevention of liver fibrosis. PMID:26730813

  16. Abate Cytochrome C induced apoptosome to protect donor liver against ischemia reperfusion injury on rat liver transplantation model

    PubMed Central

    Zhuang, Zhuonan; Lian, Peilong; Wu, Xiaojuan; Shi, Baoxu; Zhuang, Maoyou; Zhou, Ruiling; Zhao, Rui; Zhao, Zhen; Guo, Sen; Ji, Zhipeng; Xu, Kesen

    2016-01-01

    Objective: Aim of this study is to protect donor liver against ischemia-reperfusion injury by abating Cytochrome C induced apoptosome on rat model. Methods: A total of 25 clean SD inbred male rats were used in this research. The rats in ischemia-reperfusion injury group (I/R group, n=5) were under liver transplantation operation; rats in dichloroacetate diisopropylamine group (DADA group, n=5) were treated DADA before liver transplantation; control group (Ctrl group, n=5); other 10 rats were used to offer donor livers. Results: In DADA therapy group, Cytochrome C expression in donor hepatocellular cytoplasm was detected lower than that in I/R group. And the Cytochrome C induced apoptosome was also decreased in according to the lower expressions of Apaf-1 and Caspase3. Low level of cleaved PARP expression revealed less apoptosis in liver tissue. The morphology of donor liver mitochondria in DADA group was observed to be slightly edema but less than I/R group after operation 12 h. The liver function indexes of ALT and AST in serum were tested, and the results in DADA group showed it is significantly lower than I/R group after operation 12 h. The inflammation indexes of IL-6 and TNF-α expressions in DADA group were significantly lower than that in I/R group after operation 24 h. Conclusion: The dichloroacetate diisopropylamine treatment could protect the hepatocellular mitochondria in case of the spillage of Cytochrome C induced apoptosome, and protect the liver against ischemia-reperfusion injury. Thus, it may be a method to promote the recovery of donor liver function after transplantation. PMID:27186297

  17. Isolation, propagation, and characterization of rat liver serosal mesothelial cells.

    PubMed Central

    Faris, R. A.; McBride, A.; Yang, L.; Affigne, S.; Walker, C.; Cha, C. J.

    1994-01-01

    Although rat liver epithelial cell (RLEC) lines have been developed by a number of laboratories, the identity of the clonogenic nonparenchymal progenitors is unknown. To provide insight into the derivation of RLEC, we immunoisolated serosal liver mesothelial cells (LMC) and bile duct epithelial cells and attempted to propagate each epithelial cell population using culture conditions routinely employed to establish RLEC lines. Briefly, the selective reactivity of LMC with two bile duct cell surface markers, OC.2 and BD.2, was exploited to develop an immunocytochemical technique to isolate LMC. Livers were collagenase dissociated, the mesothelial capsule was "peeled" and digested with pronase to destroy contaminating hepatocytes, and rare biliary ductal epithelial cells were immunodepleted using OC.2. LMC were subsequently isolated by selective binding to magnetic beads adsorbed with BD.2 and cultured in supplemented Waymouths 752/1 media containing 10% fetal calf serum. Proliferating BD.2+ LMC rapidly formed epithelial-like monolayers that could be continuously subcultured after trypsinization. In contrast, attempts to establish cell lines from purified OC.2+ bile duct epithelial cells were unsuccessful. Results from reverse transcriptase polymerase chain reaction analysis confirmed that LMC expressed Wilms' tumor transcripts, a lineage marker for mesodermally-derived cells. In summary, our findings clearly demonstrate that LMC can be continuously propagated using culture conditions routinely employed to establish RLEC lines, an observation that supports the contention that some RLEC lines may be derived from LMC. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:7992846

  18. Proteomic analysis of liver in rats chronically exposed to fluoride.

    PubMed

    Pereira, Heloísa Aparecida Barbosa da Silva; Leite, Aline de Lima; Charone, Senda; Lobo, Janete Gualiume Vaz Madureira; Cestari, Tania Mary; Peres-Buzalaf, Camila; Buzalaf, Marília Afonso Rabelo

    2013-01-01

    Fluoride (F) is a potent anti-cariogenic element, but when ingestion is excessive, systemic toxicity may be observed. This can occur as acute or chronic responses, depending on both the amount of F and the time of exposure. The present study identified the profile of protein expression possibly associated with F-induced chronic hepatotoxicity. Weanling male Wistar rats (three-weeks old) were divided into three groups and treated with drinking water containing 0, 5 or 50 mg/L F for 60 days (n=6/group). At this time point, serum and livers were collected for F analysis, which was done using the ion-sensitive electrode, after hexamethyldisiloxane-facilitated diffusion. Livers were also submitted to histological and proteomic analyses (2D-PAGE followed by LC-MS/MS). Western blotting was done for confirmation of the proteomic data A dose-response was observed in serum F levels. In the livers, F levels were significantly increased in the 50 mg/L F group compared to groups treated with 0 and 5 mg/L F. Liver morphometric analysis did not reveal alterations in the cellular structures and lipid droplets were present in all groups. Proteomic quantitative intensity analysis detected 33, 44, and 29 spots differentially expressed in the comparisons between control vs. 5 mg/L F, control vs. 50 mg/L F, and 5 mg/L vs. 50 mg/L F, respectively. From these, 92 proteins were successfully identified. In addition, 18, 1, and 5 protein spots were shown to be exclusive in control, 5, and 50 mg/L F, respectively. Most of proteins were related to metabolic process and pronounced alterations were seen for the high-F level group. In F-treated rats, changes in the apolipoprotein E (ApoE) and GRP-78 expression may account for the F-induced toxicity in the liver. This can contribute to understanding the molecular mechanisms underlying hepatoxicity induced by F, by indicating key-proteins that should be better addressed in future studies.

  19. Liver tumour-promoting effects of oxfendazole in rats.

    PubMed

    Mitsumori, K; Onodera, H; Shoda, T; Uneyama, C; Imazawa, T; Takegawa, K; Yasuhara, K; Watanabe, T; Takahashi, M

    1997-08-01

    To examine whether oxfendazole has tumour-promoting activity, a total of 100 male Fisher 344 rats were initiated with a single ip injection of 100 mg/kg of diethylnitrosamine (DEN) or given saline vehicle alone and starting 1 wk later given diet containing 500, 250, 100, 10 or 0 ppm of oxfendazole for 8 wk. Sub-groups of five rats each from the DEN plus 250 and 0 ppm groups were killed after wk 1 of oxfendazole treatment and the remaining animals at wk 8. At the termination relative liver weights were significantly increased in the DEN-initiated and non-initiated groups treated with 250 ppm and 100 ppm or more, respectively, compared with the corresponding controls values. Light microscopical examination showed centrilobular hepatocellular hypertrophy in all animals receiving 100 ppm or more. Electron microscopy also revealed marked increases in smooth endoplasmic reticulum in hepatocytes of the DEN plus 500 ppm group. Furthermore, induction of cytochrome P-450 (CYP) 1A1/2, 2B1/2 or 4A1 was observed in the DEN plus 100 ppm group, that of CYP 1A1/2 being most marked. A similar change in CYP 1A1/2 was seen in the DEN plus 10 ppm group. The numbers and areas of connexin 32 (Cx32)-positive spots per hepatocyte were also significantly decreased in a dose-dependent manner. Similar changes in liver weights, P-450 isozymes and Cx32 immunohistochemistry were already evident in the DEN plus 250 ppm group at wk 1. The number of placental form glutathione S-transferase positive single cells was significantly increased in the DEN-initiated groups treated with 250 ppm or more. The results therefore strongly suggest that oxfendazole exerts liver tumour promotion potential.

  20. Gene expression profiling analysis of 5-hydroxytryptamine signaling pathway in rat regenerating liver and different types of liver cells.

    PubMed

    Chang, C F; Yang, J; Zhao, W M; Li, Y; Guo, P J; Li, M H; Zhou, Y; Xu, C S

    2015-01-01

    We examined the gene expression profiles of the 5-hydroxytryptamine signaling pathway in the regenerating liver and 8 types of liver cells during rat liver regeneration, and explored expression differences in 5-hydroxytryptamine signaling pathway genes at the level of tissues and cells, as well as the role of the pathway on liver regeneration. Eight types of rat regenerating liver cells were isolated using Percoll density-gradient centrifugation and immunomagnetic bead methods. Rat Genome 230 2.0 Array was used to detect expression changes in 5-hydroxytryptamine signaling pathway genes. The results showed that 26, 47, 8, 21, 16, 19, 22, 27, and 20 genes changed significantly in hepatocytes, biliary epithelial cells, hepatic stellate cells, oval cells, sinusoidal endothelial cells, Kupffer cells, pit cells, dendritic cells, and the regenerating liver, respectively. Synthetic effects of 5-hydroxytryptamine signaling pathway genes in 8 types of liver cells showed that 26 genes were expressed significantly; the expression trends of 10 genes were the same in the regenerating liver, while others were different. Based on the gene expression profiles of the 8 types of liver cells, 5-hydroxytryptamine promoted hepatocyte proliferation through the RAS and STAT3 signaling pathways, proliferation and differentiation of sinusoidal endothelial cells through the STAT3 signaling pathway, and proliferation and apoptosis of pit cells through the AKT3 signaling pathway. There were large differences in genes involved in 5-hydroxytryptamine signaling at the tissue and cellular levels; thus, liver regeneration should be studied in-depth at the cellular level to reveal the molecular mechanism of liver regeneration.

  1. Lipoprotein receptors in copper-deficient rats: high density lipoprotein binding to liver membranes

    SciTech Connect

    Hassel, C.A.; Lei, K.Y.; Marchello, J.A.

    1986-03-05

    In copper-deficient rats, the observed hyperlipoproteinemia was mainly due to the elevation in high density lipoproteins (HDL). This study was designed to determine whether an impairment in the binding of HDL to liver membrane is responsible for the hyperlipoproteinemia. Sixty male Sprague-Dawley rats were randomly divided into 2 treatments, namely copper (Cu) deficient and adequate (less than 1 and 8 mg Cu/kg of diet). After 8 weeks, plasma, heart and liver tissues were obtained. Reduction in liver Cu content and elevation in heart to body weight ratio and plasma cholesterol confirmed that rats fed the test diet were Cu-deficient. Plasma HDL isolated from both Cu-deficient and control rats were iodinated and bound to liver membranes prepared from rats of each treatment. Binding of /sup 125/I-HDL was competitively inhibited by unlabelled rat HDL from both treatments, but not by human LDL. Scatchard analysis of specific binding data showed that maximal /sup 125/I-HDL binding (per mg membrane protein) to membranes prepared from Cu-deficient rats was not lower than controls. Furthermore, the amount of /sup 125/I-HDL from deficient rats specifically bound to liver membranes prepared from either treatment was not less than the amount of /sup 125/I-HDL from control rats bound to the same membranes. The data suggest that the hyperlipoproteinemia in Cu-deficient rats may not have resulted from a decrease in the number of hepatic HDL binding sites.

  2. Regulation of Bile Salt Transport in Rat Liver

    PubMed Central

    Simon, Francis R.; Sutherland, Eileen M.; Gonzalez, Manuel

    1982-01-01

    Expansion of the bile salt pool size in rats increases maximum excretory capacity for taurocholate. We examined whether increased bile salt transport is due to recruitment of centrolobular transport units or rather to adaptive changes in the hepatocyte. Daily sodium cholate (100 mg/100 g body wt) was administered orally to rats. This treatment was well tolerated for at least 4 d and produced an 8.2-fold expansion of the bile salt pool. This expanded pool consisted predominently (99%) of cholic and deoxycholic acids. Significantly increased bile salt transport was not observed until 16 h after bile acid loading, and maximum elevations of transport capacity to 2.3-fold of control required ∼2 d. In contrast, maximum sulfobromophthalein excretion rates increased 2.2-fold as early as 4 h and actually fell to 1.5-fold increase at 4 d. We studied the possibility that this adaptive increase in bile salt secretory transport was due to changes in canalicular surface membrane area, lipid composition, or increased number of putative carriers. Canalicular membrane protein recovery and the specific activities of leucine aminopeptidase, Mg++-ATPase and 5′-nucleotidase activities were unaltered by bile salt pool expansion. The content of free and esterified cholesterol and total phospholipids was unchanged in liver surface membrane fractions compared with control values. In contrast, sodium cholate administration selectively increased specific [14C]cholic acid binding sites twofold in liver surface membrane fractions. Increased numbers of [14C]cholic acid receptors (a) was associated with the time-dependent increase in bile salt transport, and (b) was selective for the taurine conjugate of cholate and (c) was reduced by chenodeoxycholate. Changes in bile acid binding sites 16 h following taurocholate and chenodeoxycholate and the lack of change with glycocholate was associated with comparable changes in bile salt transport. In conclusion, selective bile salts increase bile

  3. Alcoholic fatty liver in rats: Role of fat and ethanol intake

    SciTech Connect

    Sankaran, H.; Deveney, C.W. ); Larkin, E.C.; Rao, G.A. )

    1991-03-11

    The claim that high intake of both ethanol and fat is essential to induce fatty liver and high blood alcohol levels (BAL) was tested. Two groups of rats were fed liquid diets containing 26% and 36% of calories as ethanol respectively. After 4 weeks, all rats were bled for BAL and some were sacrificed to obtain liver morphology. Remaining rats in Group 1 (26% ethanol) were switched to 36% ethanol diet and Group 2 (36% ethanol) to 26% ethanol diet. All rats were sacrificed after 4 weeks to obtain blood for BAL and liver morphology. The results indicate that high ethanol intake and high fat ingestion is not the criterion for induction of fatty liver. Inadequate ingestion of macronutrients plays a major role in alcoholic fatty liver and BAL.

  4. Consecutive en-bloc liver (30%)-pancreas-duodenum-spleen-stomach transplant in Lewis rats.

    PubMed

    Yoo, C H; Hong, I C; Lee, S; Nam, S; Bai, S; Kim, K; Pivetti, C D; Niewiadomski, S T; Wolf, P; Gittes, R F

    2003-01-01

    It is well-known that 30% of the remaining liver mass, following partial hepatectomy, regenerates to full original mass within 2 weeks in rats. In order to carry the transplanted rat liver to repeated transplantation, a technique of combining 30% of the liver with the pancreaticoduodenum and spleen transplantation is performed in this consecutive organ transplantation study. Our laboratory observed several 37-month-old transplanted rats by carrying through 2-3 generations, and histological disclosure were made. Because the partial liver transplants did not regenerate after the transplantation with other splanchnic organs, this technique is not so difficult though subsequent surgical maneuvers are needed and the liver histology proved entirely normal in every aspect when followed beyond the rat's life span of 24 months.

  5. Abnormal hepatic copper accumulation of spheroid composed of liver cells from LEC rats in vitro.

    PubMed

    Ueno, K; Yoshizawa, M; Satoh, T; Yoneda, S; Ohmichi, M; Yamazaki, M; Mori, Y; Suzuki, K T

    1995-11-01

    The LEC rat is a mutant strain displaying hereditary hepatitis, and shows abnormal accumulation of copper (Cu) similar to that occurring in Wilson's disease. We prepared a multicellular spheroid composed of LEC rat liver cells to investigate the mechanism for abnormal accumulation of Cu. These multicellular spheroids were prepared by detaching the monolayer on the collagen-conjugated thermo-responsive polymer coated culture dish at a temperature below the critical solution temperature and culturing on the non-adhesive substratum. Long-term cultured spheroids of LEC rat liver cells as well as SD rat liver cells were attempted. Non-parenchymal cells obtained by collagenase perfusion from the LEC liver were fewer than those from the SD liver. Cells from the LEC rat, over 11 weeks of age, did not form a cell sheet; however, a mixture of parenchymal cells from LEC rats over aged 11 weeks and non-parenchymal cells from SD rats of any age yielded intact spheroids. We examined the toxicity, the accumulation and distribution of Cu in spheroids. The accumulation of Cu in LEC spheroids was higher than that in SD spheroids. Results suggest that spheroids consisting of LEC liver cells are useful as an alternative model to in vivo tests to investigate the mechanism for abnormal accumulation of Cu in liver.

  6. Effect of praseodymium chloride on liver microsomal enzymes of rats.

    PubMed

    Oga, S; Galvão, J F; Yasaka, W J; Araujo Filho, A P

    1986-06-01

    A single i.v. dose (5 mg/kg) of a light lanthanon, praseodymium, prolonged the duration of hexobarbital-induced sleep and zoxazolamine-induced paralysis, as well as it modified pharmacokinetic parameters of hexobarbital and zoxazolamine, in rats. Half-lives (t1/2) and area under the curve (AUC) were increased, while elimination coefficient (beta) and clearance (Cl) were decreased. However, in daily doses of 1 mg/kg i.p. for 15 days, praseodymium did not alter pharmacological effects and pharmacokinetic parameters. The in vitro hydroxylation of hexobarbital and zoxazolamine by liver microsomes was inhibited when the animals were treated previously with a single i.v. dose (5 mg/kg) of praseodymium chloride. In these animals, the amount of cytochromes P-450 and b5 were reduced significantly, whereas that of NADPH-cytochrome c reductase remained unchanged. The pretreatment of animals with phenobarbital normalized the microsomal enzyme impairment caused by praseodymium.

  7. Purification and characterization of aldehyde dehydrogenase from rat liver mitochondria.

    PubMed

    Senior, D J; Tsai, C S

    1988-04-01

    Nicotinamide adenine dinucleotide- and nicotinamide adenine dinucleotide phosphate-dependent dehydrogenase activities from rat liver mitochondria have been copurified to homogeneity using combined DEAE, Sepharose, and affinity chromatographic procedures. The enzyme has a native molecular weight of 240,000 and subunit molecular weight of 60,000. The enzyme is tetrameric consisting of four identical subunits as revealed by electrophoresis and terminal analyses. A partial summary of physical properties is provided. The amino acid composition by acid hydrolysis is reported. Specific activities for various NAD(P)+ analogs and alkanal substrates were compared. The action of the effectors chloral hydrate, disulfiram, diethylstilbestrol, and Mg2+ and K+ ions were also investigated. PMID:3355167

  8. Native fluorescence characteristics of blood plasma during rat liver regeneration

    NASA Astrophysics Data System (ADS)

    Ganesan, Singaravelu; Madhuri, S.; Anuradha, V.; Namasivayam, A.; Parmeswearan, Diagaradjane

    1999-05-01

    Native fluorescence characteristics of blood plasma was studied in the visible region, during the regenerating phase of the rat liver tissue. Animals were subjected to partial hepatectomy (PH). Blood samples were collected after several intervals of post PH time and also from control animals. Native fluorescence spectra of blood plasma were measured at 405 nm excitation. In addition to the primary emission peak around 440 nm, the fluorescence spectra of experimental group of animals showed distinct secondary emission peak around 620 nm, which is found to be absent in the case of control animals. This may be attributed to the presence of endogenous porphyrins. The fluorescence intensity at 620 nm was found to be maximum at about 16 hrs of post PH time and it decreased thereafter with increasing post PH time. The spectral differences between controls and experimental animals were found to be minimal at 240 hrs of post PH time.

  9. Characteristic expression profiles induced by genotoxic carcinogens in rat liver.

    PubMed

    Ellinger-Ziegelbauer, Heidrun; Stuart, Barry; Wahle, Brad; Bomann, Werner; Ahr, Hans-Jurgen

    2004-01-01

    When applied in toxicological studies, the recently developed gene expression profiling techniques using microarrays, which brought forth the new field of toxicogenomics, facilitate the interpretation of a toxic compound's mechanism of action. In this study, we investigated whether genotoxic carcinogens at doses known to induce liver tumors in the 2-year rat bioassay deregulate a common set of genes in a short-term in vivo study and, if so, whether these deregulated genes represent defined biological pathways. Rats were dosed with the four genotoxic hepatocarcinogens dimethylnitrosamine (4 mg/kg/day), 2-nitrofluorene (44 mg/kg/day), aflatoxin B1 (0.24 mg/kg/day), and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK, 20 mg/kg/day). After treatment for up to 14 days, the expression profiles of the livers were analyzed on Affymetrix RG_U34A microarrays. Among the significantly upregulated genes were a set of target genes of the tumor suppressor protein p53, indicating a DNA damage response. Such a response was expected and, therefore, confirmed the validity of our approach. In addition, the gene expression changes suggest a specific detoxification response, the activation of proliferative and survival signaling pathways, and some cell structural changes. These responses were strong throughout the 14 day time course for 2-nitrofluorene and aflatoxin B1; in the case of dimethylnitrosamine and NNK, the effects were weakly detectable at day 1 and then increased with time. For dimethylnitrosamine and aflatoxin B1, which caused observable inflammation in vivo, we found a corresponding upregulation of inflammatory genes at the same time points. Thus, by the toxicogenomic analysis of short-term in vivo studies, we identified genes and pathways commonly deregulated by genotoxic carcinogens, which may be indicative for the early events in tumorigenesis and, thus, predictive of later tumor development. PMID:14600272

  10. Burn trauma disrupts circadian rhythms in rat liver

    PubMed Central

    Rao, Rohit; Yang, Qian; Orman, Mehmet A; Berthiaume, Francois; Ierapetritou, Marianthi G; Androulakis, Ioannis P

    2016-01-01

    Circadian rhythms play an important role in maintaining homeostasis and solid organ function. The purpose of this study is to assess the implications of burn injury in rats on the underlying circadian patterns of gene expression in liver. Circadian-regulated genes and burn-induced genes were identified by applying consensus clustering methodology to temporally differentially expressed probe sets obtained from burn and sham-burn data sets. Of the liver specific genes which we hypothesize that exhibit circadian rhythmicity, 88% are not differentially expressed following the burn injury. Specifically, the vast majority of the circadian regulated-genes representing central carbon and nitrogen metabolism are “up-regulated” after the burn injury, indicating the onset of hypermetabolism. In addition, cell-cell junction and membrane structure related genes showing rhythmic behavior in the control group were not differentially expressed across time in the burn group, which could be an indication of hepatic damage due to the burn. Finally, the suppression of the immune function related genes is observed in the postburn phase, implying the severe “immunosuppression”. Our results demonstrated that the short term response (24-h post injury) manifests a loss of circadian variability possibly compromising the host in terms of subsequent challenges. PMID:27335693

  11. In vivo assembly of tight junctions in fetal rat liver.

    PubMed

    Montesano, R; Friend, D S; Perrelet, A; Orci, L

    1975-11-01

    Examination of glutaraldehyde-fixed, freeze-fractured livers from 14-15-day rat fetuses provided the basis for the following observations. Membrane particles align in otherwise poorly particulated areas of the presumptive pericanalicular plasma membrane (A face), frequently forming a discontinuous "honey-comb" network joining small particle islands. Even at this early stage, contiguous B-fracture faces contain furrows, rather than rows of pits, distinguishing the linear particle aggregates on the A face as developing tight junctions rather than gap junctions. Short segments of these linear arrays merge with smooth ridges clearly identifiable as segments of discontinuous tight junctions. With the continuing confluence of particulate and smooth ridge segments, mature tight junctions become fully appreciable. We conclude that tight junctions form de novo by the alignment and fusion of separate particles into beaded ridges which, in turn, become confluent and are transformed into continuous smooth ones. At 21 days of fetal life, most of the images of assembly have disappeared, and the liver reveals well-formed bile canaliculi sealed by mature tight junctions. PMID:1194351

  12. Disrupted Renal Mitochondrial Homeostasis after Liver Transplantation in Rats

    PubMed Central

    Liu, Qinlong; Krishnasamy, Yasodha; Rehman, Hasibur; Lemasters, John J.; Schnellmann, Rick G.; Zhong, Zhi

    2015-01-01

    Background Suppressed mitochondrial biogenesis (MB) contributes to acute kidney injury (AKI) after many insults. AKI occurs frequently after liver transplantation (LT) and increases mortality. This study investigated whether disrupted mitochondrial homeostasis plays a role in AKI after LT. Methods Livers were explanted from Lewis rats and implanted after 18 h cold storage. Kidney and blood were collected 18 h after LT. Results In the kidney, oxidative phosphorylation (OXPHOS) proteins ATP synthase-β and NADH dehydrogenase-3 decreased 44% and 81%, respectively, with marked reduction in associated mRNAs. Renal PGC-1α, the major regulator of MB, decreased 57% with lower mRNA and increased acetylation, indicating inhibited synthesis and suppressed activation. Mitochondrial transcription factor-A, which controls mtDNA replication and transcription, protein and mRNA decreased 66% and 68%, respectively, which was associated with 64% decreases in mtDNA. Mitochondrial fission proteins Drp-1 and Fis-1 and mitochondrial fusion protein mitofusin-1 all decreased markedly. In contrast, PTEN-induced putative kinase 1 and microtubule-associated protein 1A/1B-light chain 3 increased markedly after LT, indicating enhanced mitophagy. Concurrently, 18- and 13-fold increases in neutrophil gelatinase-associated lipocalin and cleaved caspase-3 occurred in renal tissue. Both serum creatinine and blood urea nitrogen increased >2 fold. Mild to moderate histological changes were observed in the kidney, including loss of brush border, vacuolization of tubular cells in the cortex, cast formation and necrosis in some proximal tubular cells. Finally, myeloperoxidase and ED-1 also increased, indicating inflammation. Conclusion Suppression of MB, inhibition of mitochondrial fission/fusion and enhancement of mitophagy occur in the kidneys of recipients of liver grafts after long cold storage, which may contribute to the occurrence of AKI and increased mortality after LT. PMID:26480480

  13. Interaction of human lactoferrin with the rat liver

    SciTech Connect

    Debanne, M.T.; Regoeczi, E.; Sweeney, G.D.; Krestynski, F.

    1985-04-01

    Binding of human lactoferrin (hLf) by purified rat liver plasma membranes was studied to clarify whether the liver possesses specific hLf receptors. The binding was rapid between 4 degrees and 37 degrees C, with a pH optimum close to 5.0. At 22 degrees C and in glycine-NaOH (5 mM, pH 7.4) containing 150 mM NaCl and 0.5% albumin, 1 microgram of membrane bound a maximum of 11.8 ng hLf. The dissociation constant of the interaction was 1.6 X 10(-7) M. Other proteins of high isoelectric points (lactoperoxidase, lysozyme, and particularly salmine sulfate) and a piperazine derivative inhibited hLf binding in a concentration- dependent manner. In contrast, monosaccharides (galactose, N- acetylgalactosamine, mannose, and fucose) were ineffective. By omitting NaCl from the incubation buffer, binding was increased 3.6-fold. Erythrocyte ghosts bound hLf less firmly and alveolar macrophages more firmly than hepatic plasma membranes. Liver cell fractionations performed after the intravenous injection of labeled hLf showed that approximately 88% of the hepatic radioligand was associated with parenchymal cells. When binding was expressed per unit of cell volume, however, more hLf was present in nonparenchymal than in parenchymal cells, implying that the above value was determined by the relative cell masses rather than affinities alone. It is concluded that the binding of hLf by hepatic plasma membranes is electrostatic, i.e., is mediated by the cationic nature of the ligand, and that it is explicable in terms of a ''specific nonreceptor interaction'' of the generalized type proposed by Cuatrecasas and Hollenberg.

  14. A study of liver microsomal enzymes in rats following propoxur (Baygon) administration.

    PubMed

    Nelson, D L; Lamb, D W; Mihail, F

    1984-08-01

    Groups of rats were given either propoxur, were left as untreated controls, or were given phenobarbital, DDT, chlordane or toxaphene which are known to induce liver microsomal detoxification enzymes. Microsomal enzyme activity was measured by testing the ability of liver homogenates to degrade EPN (O-ethyl O-(4-nitrophenyl) phenylphosphonothioate) to p-nitrophenol. The activity of aminopyrine-N-demethylase, cytochrome P-450 and p-nitroanisole-O-demethylase in liver homogenates of rats receiving propoxur was measured. Liver microsomal detoxification enzymes were not induced by propoxur exposure.

  15. Prolonged exposure of cholestatic rats to complete dark inhibits biliary hyperplasia and liver fibrosis

    PubMed Central

    Han, Yuyan; Onori, Paolo; Meng, Fanyin; DeMorrow, Sharon; Venter, Julie; Francis, Heather; Franchitto, Antonio; Ray, Debolina; Kennedy, Lindsey; Greene, John; Renzi, Anastasia; Mancinelli, Romina; Gaudio, Eugenio; Glaser, Shannon

    2014-01-01

    Biliary hyperplasia and liver fibrosis are common features in cholestatic liver disease. Melatonin is synthesized by the pineal gland as well as the liver. Melatonin inhibits biliary hyperplasia of bile duct-ligated (BDL) rats. Since melatonin synthesis (by the enzyme serotonin N-acetyltransferase, AANAT) from the pineal gland increases after dark exposure, we hypothesized that biliary hyperplasia and liver fibrosis are diminished by continuous darkness via increased melatonin synthesis from the pineal gland. Normal or BDL rats (immediately after surgery) were housed with light-dark cycles or complete dark for 1 wk before evaluation of 1) the expression of AANAT in the pineal gland and melatonin levels in pineal gland tissue supernatants and serum; 2) biliary proliferation and intrahepatic bile duct mass, liver histology, and serum chemistry; 3) secretin-stimulated ductal secretion (functional index of biliary growth); 4) collagen deposition, liver fibrosis markers in liver sections, total liver, and cholangiocytes; and 5) expression of clock genes in cholangiocytes. In BDL rats exposed to dark there was 1) enhanced AANAT expression/melatonin secretion in pineal gland and melatonin serum levels; 2) improved liver morphology, serum chemistry and decreased biliary proliferation and secretin-stimulated choleresis; and 4) decreased fibrosis and expression of fibrosis markers in liver sections, total liver and cholangiocytes and reduced biliary expression of the clock genes PER1, BMAL1, CLOCK, and Cry1. Thus prolonged dark exposure may be a beneficial noninvasive therapeutic approach for the management of biliary disorders. PMID:25214401

  16. Age-dependent changes in rat liver prenyltransferases.

    PubMed

    Thelin, A; Runquist, M; Ericsson, J; Swiezewska, E; Dallner, G

    1994-10-20

    Mevalonate pathway lipids including cholesterol, ubiquinone and dolichol, are of great importance for cellular function. Many of the enzymes of this pathway are thus strictly regulated. During development of the rat, the cellular levels of certain of these lipids vary. Prenyltransferases have been investigated and it is reported here that farnesyl pyrophosphate synthase activity in rat liver cytosol decreases after birth to a lower, steady level. This decrease is not paralleled by the level of synthase protein, which shows two maxima, one immediately after birth and the other 30 days later. cis-Prenyltransferase activity is low after birth, increases continuously up to day-54 and then decreases to a low level which was maintained throughout the remainder of the study (365 days). Squalene synthase exhibits high activity after birth, but decreases during the first 100 days thereafter, and subsequently remains at the low level thus reached. In contrast to these changes in the activities of the prenyltransferases, the level of cholesterol is constant and the dolichol concentration increases continuously throughout the entire period studied.

  17. Etoxazole is Metabolized Enantioselectively in Liver Microsomes of Rat and Human in Vitro.

    PubMed

    Yao, Zhoulin; Qian, Mingrong; Zhang, Hu; Nie, Jing; Ye, Jingqing; Li, Zuguang

    2016-09-01

    Acaricide etoxazole belongs to the ovicides/miticides diphenyloxazole class, affecting adults to lay sterile eggs by inhibiting chitin biosynthesis possibly. The reverse-phase HPLC-MS/MS method was used to determine the etoxazole enantiomers. The enantioselective degradation behavior of rac-etoxazole in liver microsomes of rat and human in vitro with NADPH was dramatically different. The t1/2 of (R)-etoxazole was 15.23 min in rat liver microsomes and 30.54 min in human liver microsomes, while 21.73 and 23.50 min were obtained for (S)-etoxazole, respectively. The Vmax of (R)-etoxazole was almost 5-fold of (S)-etoxazole in liver microsomes of rat in vitro. However, the Vmax of (S)-etoxazole was almost 2-fold of (R)-etoxazole in liver microsomes of human in vitro. The CLint of etoxazole was also shown the enantioselectivity on the contrary in liver microsomes of rat and human. These results indicated that the metabolism of two etoxazole enantiomers was selective in liver microsomes of rat and human in vitro, and enantioselectivity in the two kinds of liver microsomes was in the difference in degradation performance. The reason might be related to the composition and content involved in the enzyme system. PMID:27479246

  18. Folic acid supplementation for 4 weeks affects liver morphology in aged rats.

    PubMed

    Roncalés, María; Achón, María; Manzarbeitia, Félix; Maestro de las Casas, Carmen; Ramírez, Carmen; Varela-Moreiras, Gregorio; Pérez-Miguelsanz, Julia

    2004-05-01

    Several countries have approved universal folic acid (FA) fortification to prevent neural tube defects and/or high homocysteine levels; this has led to a chronic intake of FA. Traditionally, the vitamin is considered to be safe and nontoxic, except for the potential masking of vitamin B-12 deficiency. Recent reports from our laboratories showed several effects of high-dose folate supplementation in rats. In this work, we compared the effect of FA on the liver of weanling (3 wk) and aged (18 mo) male rats fed either a diet supplemented with 40 mg FA/kg diet or a control diet (1 mg FA/kg diet) for 4 wk. FA supplementation did not alter serum aspartate aminotransferase, alanine aminotransferase, urea, glucose oxidase, total bilirubin, or uric acid. Routine histological staining as well as immunohistochemistry with proliferating cell nuclear antibody for dividing cells, and cytokeratin-8 against bile ductal cells, showed that aged, supplemented rats had the same number of hepatocytes as both control and supplemented weanling rats, and tended to have more (17%, P = 0.07) hepatocytes than aged, control rats. Moreover, the bile duct cells of aged, control rats proliferated and transformed into cholestatic rosettes at a higher frequency than in aged, supplemented rats. The morphology of the liver in weanling rats was similar in both diet groups, and comparable to the supplemented, aged rats, thus indicating that a high intake of FA improves normal liver morphology in livers of aged rats.

  19. Estrogenic activity of an environmental pollutant, 2-nitrofluorene, after metabolic activation by rat liver microsomes.

    PubMed

    Fujimoto, Takashi; Kitamura, Shigeyuki; Sanoh, Seigo; Sugihara, Kazumi; Yoshihara, Shin'ichi; Fujimoto, Nariaki; Ohta, Shigeru

    2003-04-01

    In this study, the metabolic activation of 2-nitrofluorene (NF) to estrogenic compounds was examined. NF was negative in estrogen reporter assays using estrogen-responsive yeast and human breast cancer cell line MCF-7. However, the compound exhibited estrogenic activity after incubation with liver microsomes of 3-methylcholanthrene-treated rats in the presence of NADPH. Minor estrogenic activity was observed when liver microsomes of untreated or phenobarbital-treated rats were used instead of those from 3-methylcholanthrene-treated rats. When the compound was incubated with the liver microsomes of 3-methylcholanthrene-treated rats in the presence of NADPH, 7-hydroxy-2-nitrofluorene (7-OH-NF) was formed as a major metabolite. However, little of the metabolite was formed by liver microsomes of untreated or phenobarbital-treated rats. Rat recombinant cytochrome P450 1A1 exhibited a significant oxidase activity toward NF, affording 7-OH-NF. Liver microsomes of phenobarbital-treated rats also enhanced oxidase activity toward NF. In this case, 9-hydroxy-2-nitrofluorene was formed. 7-OH-NF exhibited a significant estrogenic activity, while the activity of 9-hydroxy-2-nitrofluorene was much lower. These results suggest that the estrogenic activity of NF was due to formation of the 7-hydroxylated metabolite by liver microsomes. PMID:12659833

  20. In vitro immunosuppressive activity of tacrolimus dihydrodiol precursors obtained by chemical oxidation and identification of a new metabolite of SDZ-RAD by electrospray and electrospray-linked scan mass spectrometry.

    PubMed

    Lhoëst, G; Hertsens, R; Verbeeck, R K; Maton, N; Wallemacq, P; Dehoux, J P; Latinne, D

    2001-08-01

    Different tacrolimus epoxides and dihydrodiol epoxides arising from the chemical oxidation of the parent drug are described. Open-chain tautomeric forms involving the lactone function were identified for the tacrolimus epoxides. Moreover, the identification by electrospray and electrospray linked scan mass spectrometry of an SDZ-RAD C16-C27 O-demethyl 17, 18-19, 20-21, 22 tris-epoxide new metabolite isolated from pig liver microsomes is reported. The in vitro immunosuppressive activity, using mixed lymphocyte reactions of the two macrolide reported oxidation compounds are discussed. PMID:11523088

  1. Effects of parsley (Petroselinum crispum) on the liver of diabetic rats: a morphological and biochemical study.

    PubMed

    Bolkent, S; Yanardag, R; Ozsoy-Sacan, O; Karabulut-Bulan, O

    2004-12-01

    Parsley is used by diabetics in Turkey to reduce blood glucose. The present study aims to investigate both the morphological and biochemical effects of parsley on liver tissue. Rat hepatocytes were examined by light and electron microscopy. Degenerative changes were observed in the hepatocytes of diabetic rats. These degenerative changes were significantly reduced or absent in the hepatocytes of diabetic rats treated with parsley. Blood glucose levels, alanine transaminase and alkaline phosphatase were observed to be raised in diabetic rats. Diabetic rats treated with parsley demonstrated significantly lower levels of blood glucose, alanine transaminase and alkaline phosphatase. The present study suggests that parsley demonstrates a significant hepatoprotective effect in diabetic rats.

  2. Participation of liver progenitor cells in liver regeneration: lack of evidence in the AAF/PH rat model.

    PubMed

    Dusabineza, Ange-Clarisse; Van Hul, Noémi K; Abarca-Quinones, Jorge; Starkel, Peter; Najimi, Mustapha; Leclercq, Isabelle A

    2012-01-01

    When hepatocyte proliferation is impaired, liver progenitor cells (LPC) are activated to participate in liver regeneration. We used the 2-acetaminofluorene/partial hepatectomy (AAF/PH) model to evaluate the contribution of LPC to liver cell replacement and function restoration. Fischer rats subjected to AAF/PH (or PH alone) were investigated 7, 10 and 14 days post-hepatectomy. Liver mass recovery (LMR) was estimated, and the liver mass to body weight ratio calculated. We used serum albumin and bilirubin levels, and liver albumin mRNA levels to assess the liver function. LPC expansion was analyzed by cytokeratin 19 (CK19), glutathione S-transferase protein (GSTp) immunohistochemistry and by CK19, CD133, transforming growth factor-β1 and hepatocyte growth factor mRNA expression in livers. Cell proliferation was evaluated by Ki67 and BrdU immunostaining. Compared with PH alone where LMR was ∼100% 14 days post-PH, LMR was defective in AAF/PH rats (64.1±15.5%, P=0.0004). LPC expansion was scarce in PH livers (0.5±0.4% of CK19(+) area), but significant in AAF/PH livers (8.5±7.2% of CK19(+)), and inversely correlated to LMR (r(2)=0.63, P<0.0001). A quarter of AAF/PH animals presented liver failure (low serum albumin and high serum bilirubin) 14 days post-PH. Compared with animals with preserved function, this was associated with a lower LMR (50±6.8 vs 74.6±9.4%, P=0.0005), a decreased liver to body weight ratio (2±0.3 vs 3.5±0.6%, P=0.001), and a larger LPC expansion such as proliferating Ki67(+) LPC covered 17.4±4.2% of the liver parenchyma vs 3.1±1.5%, (P<0.0001). Amongst those, rare LPC with an intermediate hepatocyte-like phenotype were seen. Also, less than 2% of hepatocytes were engaged into the cell cycle (Ki67(+)), while more numerous (∼25% of hepatocytes) in the livers with preserved function. These observations suggest that, in this model, the efficient recovery of the liver function was ensured rather by the proliferation of mature hepatocytes

  3. Alpha-lipoic acid treatment of acetaminophen-induced rat liver damage.

    PubMed

    Mahmoud, Y I; Mahmoud, A A; Nassar, G

    2015-01-01

    Acetaminophen (paracetamol) is a well-tolerated analgesic and antipyretic drug when used at therapeutic doses. Overdoses, however, cause oxidative stress, which leads to acute liver failure. Alpha lipoic acid is an antioxidant that has proven effective for ameliorating many pathological conditions caused by oxidative stress. We evaluated the effect of alpha lipoic acid on the histological and histochemical alterations of liver caused by an acute overdose of acetaminophen in rats. Livers of acetaminophen-intoxicated rats were congested and showed centrilobular necrosis, vacuolar degeneration and inflammatory cell infiltration. Necrotic hepatocytes lost most of their carbohydrates, lipids and structural proteins. Liver sections from rats pre-treated with lipoic acid showed fewer pathological changes; the hepatocytes appeared moderately vacuolated with moderate staining of carbohydrates and proteins. Nevertheless, alpha lipoic acid at the dose we used did not protect the liver fully from acetaminophen-induced acute toxicity. PMID:26179071

  4. Alpha-lipoic acid treatment of acetaminophen-induced rat liver damage.

    PubMed

    Mahmoud, Y I; Mahmoud, A A; Nassar, G

    2015-01-01

    Acetaminophen (paracetamol) is a well-tolerated analgesic and antipyretic drug when used at therapeutic doses. Overdoses, however, cause oxidative stress, which leads to acute liver failure. Alpha lipoic acid is an antioxidant that has proven effective for ameliorating many pathological conditions caused by oxidative stress. We evaluated the effect of alpha lipoic acid on the histological and histochemical alterations of liver caused by an acute overdose of acetaminophen in rats. Livers of acetaminophen-intoxicated rats were congested and showed centrilobular necrosis, vacuolar degeneration and inflammatory cell infiltration. Necrotic hepatocytes lost most of their carbohydrates, lipids and structural proteins. Liver sections from rats pre-treated with lipoic acid showed fewer pathological changes; the hepatocytes appeared moderately vacuolated with moderate staining of carbohydrates and proteins. Nevertheless, alpha lipoic acid at the dose we used did not protect the liver fully from acetaminophen-induced acute toxicity.

  5. Polyploidization delay in rat hepatocytes under liver growth inhibition by hypokinesia

    NASA Technical Reports Server (NTRS)

    Faktor, V. M.; Malyutin, V. F.; Li, S. Y.; Brodskiy, V. Y.

    1981-01-01

    A study of young rats, weighing 55 to 59 g, after being for 10 days in conditions of limited mobility, shows a retardation of body growth as well as that of liver growth. The decrease in the rate of growth is accompanied by a reduction of cell proliferation and by delay polyploidization of hepatocytes in the liver of experimental rats. The materials, methods, and results of research are discussed.

  6. Medium chain triglycerides dose-dependently prevent liver pathology in a rat model of non-alcoholic fatty liver disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolic syndrome is often accompanied by development of hepatic steatosis and less frequently by nonalcoholic fatty liver disease (NAFLD) leading to nonalcoholic steatohepatitis (NASH). Replacement of corn oil with medium chain triacylglycerols (MCT) in the diets of alcohol-fed rats has been show...

  7. PPAR{alpha} agonists up-regulate organic cation transporters in rat liver cells

    SciTech Connect

    Luci, Sebastian; Geissler, Stefanie; Koenig, Bettina; Koch, Alexander; Stangl, Gabriele I.; Hirche, Frank; Eder, Klaus . E-mail: klaus.eder@landw.uni-halle.de

    2006-11-24

    It has been shown that clofibrate treatment increases the carnitine concentration in the liver of rats. However, the molecular mechanism is still unknown. In this study, we observed for the first time that treatment of rats with the peroxisome proliferator activated receptor (PPAR)-{alpha} agonist clofibrate increases hepatic mRNA concentrations of organic cation transporters (OCTNs)-1 and -2 which act as transporters of carnitine into the cell. In rat hepatoma (Fao) cells, treatment with WY-14,643 also increased the mRNA concentration of OCTN-2. mRNA concentrations of enzymes involved in carnitine biosynthesis were not altered by treatment with the PPAR{alpha} agonists in livers of rats and in Fao cells. We conclude that PPAR{alpha} agonists increase carnitine concentrations in livers of rats and cells by an increased uptake of carnitine into the cell but not by an increased carnitine biosynthesis.

  8. Hepcidin expression in the liver of rats fed a magnesium-deficient diet.

    PubMed

    Ishizaki, Natsumi; Kotani, Megumi; Funaba, Masayuki; Matsui, Tohru

    2011-10-01

    Mg deficiency accelerates Fe accumulation in the liver, which may induce various metabolic disturbances. In the present study, we examined the gene expression of Hepcidin, a peptide hormone produced in the liver to regulate intestinal Fe absorption negatively, in Mg-deficient rats. Although liver Fe concentration was significantly higher in rats fed an Mg-deficient diet for 4 weeks than in rats fed a control diet, Hepcidin expression in the liver was comparable between the dietary groups. Previous studies revealed that Fe overload up-regulated Hepcidin expression through transcriptional activation by Fe-induced bone morphogenetic protein (Bmp) 6, a growth/differentiation factor belonging to the transforming growth factor-β family, in the liver. Mg deficiency up-regulated the expression of Bmp6 but did not affect the expression of inhibition of DNA binding 1, a sensitive Bmp-responsive gene. In addition, the expression of Bmp receptors such as activin receptor-like kinase 2 (Alk2), activin receptor type IIA (Actr2a), activin receptor type IIB (Actr2b) and Bmp type II receptor (Bmpr2) was lower in the liver of Mg-deficient rats than in that of control rats. The present study indicates that accumulation of hepatic Fe by Mg deficiency is a stimulant inducing Bmp6 expression but not Hepcidin expression by blunting Bmp signalling possibly resulting from down-regulation of the receptor expression. Unresponsive Hepcidin expression may have a role in Mg deficiency-induced changes related to increased liver Fe.

  9. Change of drug excretory pathway by CCl4-induced liver dysfunction in rat.

    PubMed

    Okumura, Hirotoshi; Katoh, Miki; Minami, Keiichi; Nakajima, Miki; Yokoi, Tsuyoshi

    2007-08-01

    Liver dysfunction affects the pharmacokinetics of drugs. The liver plays an important role in drug excretion as well as drug metabolism and pharmacokinetics. In the present study, the relationship between changes in the cefmetazole (CMZ) excretory pathway and the degree of liver dysfunction induced by CCl(4) treatment was investigated. CMZ is mainly excreted as an unchanged form in feces in control rats. Depending on the serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), urinary CMZ excretion was increased, whereas fecal CMZ excretion was decreased in rat with liver dysfunction. The AUC of CMZ in rats with severe liver dysfunction was approximately 2-fold higher than that in control rats. Since drug transporters could be involved in drug excretion, changes in the expression of representative hepatic drug transporters in liver dysfunction were investigated by rat DNA microarray. Basolateral solute carrier transporters such as Ntcp, Oct1, and Oatp2 were decreased and basolateral ATP-binding cassette transporters such as Mrp3 and Mrp4 were increased by the CCl(4) treatment. On the other hand, canalicular Mrp2 and Bsep were decreased, but Mdr1 was increased. However, the transporter system for CMZ has not been identified yet. In conclusion, we clarified that the fecal and urinary excretory profiles of CMZ were changed clearly depending on the serum AST and ALT levels in liver dysfunction. The changes in the CMZ excretory pathway might be responsible for the changes in the expression of drug transporters.

  10. Chronic ethanol inhibits receptor-stimulated phosphoinositide hydrolysis in rat liver slices

    SciTech Connect

    Gonzales, R.A.; Crews, F.T. )

    1991-03-01

    The effects of chronic ethanol feeding on norepinephrine (NE)- and arginine-vasopressin (AVP)-stimulated phosphoinositide (PI) hydrolysis in rat liver slices was determined. The maximum NE-stimulated PI response was significantly reduced by 40% in liver slices from 8-month-old rats which had been treated for 5 months with a liquid diet containing ethanol compared to pair-fed controls. The maximum AVP-stimulated PI response was decreased by 39% in liver slices from the ethanol-fed rats compared to control. EC50 values for NE- and AVP-stimulated PI hydrolysis in liver slices were not affected by the chronic ethanol treatment. Similar reductions in the maximal NE- and AVP-stimulated PI hydrolysis (28% and 27%, respectively) were found in 22-month-old rats which had been maintained on an ethanol containing diet for 5 months compared to pair-fed controls. The binding of (3H)prazosin and (3H)AVP to liver plasma membranes from 8-month-old ethanol-fed rats was not significantly different from binding to liver membranes from sucrose-fed controls. Our data suggest that chronic ethanol ingestion may lead to a reduction in PI-linked signal transduction in liver.

  11. Motor activity is modulated via different neuronal circuits in rats with chronic liver failure than in normal rats.

    PubMed

    Cauli, Omar; Mlili, Nisrin; Llansola, Marta; Felipo, Vicente

    2007-04-01

    The mechanisms by which liver failure alters motor function remain unclear. It has been suggested that liver disease alters the neuronal circuit between basal ganglia and cortex that modulates motor function. Activation of group I metabotropic glutamate receptors in the nucleus accumbens (NAcc) by injecting (S)-3,5-dihydroxyphenylglycine (DHPG) activates this circuit and induces locomotion We analysed by in vivo brain microdialysis the function of the circuits that modulate motor function in rats with liver failure due to portacaval shunt (PCS). We inserted cannulae in the NAcc and microdialysis probes in the NAcc, ventral pallidum (VP), substantia nigra pars reticulata (SNr), medio-dorsal thalamus (MDT), ventro-medial thalamus (VMT) or prefrontal cortex (PFCx). We injected DHPG in the NAcc and analysed extracellular neurotransmitters concentration in these areas. The results indicate that in control rats DHPG induces locomotion by activating the 'normal' neuronal circuit: NAcc --> VP --> MDT --> PFCx. In PCS rats this circuit is not activated. In PCS rats, DHPG injection activates an 'alternative' circuit: NAcc --> SNr --> VMT --> PFCx. This circuit is not activated in control rats. DHPG injection increases dopamine in the NAcc of control but not of PCS rats, and glutamate in PCS but not in control rats. DHPG-induced increase in dopamine would activate the 'normal' neuronal circuit, while an increase in glutamate would activate the 'alternative' circuit. The identification of the mechanisms responsible for altered motor function and coordination in liver disease would allow designing treatments to improve motor function in patients with hepatic encephalopathy.

  12. High affinity binding of (/sup 3/H)cocaine to rat liver microsomes

    SciTech Connect

    El-Maghrabi, E.A.; Calligaro, D.O.; Eldefrawi, M.E.

    1988-01-01

    )/sup 3/H)cocaine bound reversible, with high affinity and stereospecificity to rat liver microsomes. Little binding was detected in the lysosomal, mitochondrial and nuclear fractions. The binding kinetics were slow and the kinetically calculated K/sub D/ was 2 nM. Induction of mixed function oxidases by phenobarbital did not produce significant change in (/sup 3/H)cocaine binding. On the other hand, chronic administration of cocaine reduced (/sup 3/H)cocaine binding drastically. Neither treatment affected the affinity of the liver binding protein for cocaine. Microsomes from mouse and human livers had less cocaine-binding protein and lower affinity for cocaine than those from rat liver. Binding of (/sup 3/H)cocaine to rat liver microsomes was insensitive to monovalent cations and > 10 fold less sensitive to biogenic amines than the cocaine receptor in rat striatum. However, the liver protein had higher affinity for cocaine and metabolites except for norcocaine. Amine uptake inhibitors displaced (/sup 3/H)cocaine binding to liver with a different rank order of potency than their displacement of (/sup 3/H)cocaine binding to striatum. This high affinity (/sup 3/H)cocaine binding protein in liver is not likely to be monooxygenase, but may have a role in cocaine-induced hepatotoxicity

  13. Inositol is a constituent of detergent-solubilized immunoaffinity-purified rat liver 5'-nucleotidase.

    PubMed Central

    Bailyes, E M; Ferguson, M A; Colaco, C A; Luzio, J P

    1990-01-01

    myo-Inositol analysis of detergent-solubilized immunoaffinity-purified rat liver 5'-nucleotidase showed the presence of 1 mol of myo-inositol/mol of enzyme monomer. This provides unequivocal evidence that the ectoenzyme 5'-nucleotidase is attached to liver membranes by a glycosyl-phosphatidylinositol lipid anchor. PMID:2306224

  14. Long-term pathological and immunohistochemical features in the liver after intraoperative whole-liver irradiation in rats.

    PubMed

    Imaeda, Masumi; Ishikawa, Hitoshi; Yoshida, Yukari; Takahashi, Takeo; Ohkubo, Yu; Musha, Atsushi; Komachi, Mayumi; Nakazato, Yoichi; Nakano, Takashi

    2014-07-01

    Radiation therapy (RT) has become particularly important recently for treatment of liver tumors, but there are few experimental investigations pertaining to radiation-induced liver injuries over long-term follow-up periods. Thus, the present study examined pathological liver features over a 10-month period using an intraoperative whole-liver irradiation model. Liver function tests were performed in blood samples, whereas cell death, cell proliferation, and fibrotic changes were evaluated pathologically in liver tissues, which were collected from irradiated rats 24 h, 1, 2, 4 and 40 weeks following administration of single irradiation doses of 0 (control), 15 or 30 Gy. The impaired liver function, increased hepatocyte number, and decreased apoptotic cell proportion observed in the 15 Gy group, but not the 30 Gy group, returned to control group levels after 40 weeks; however, the Ki-67 indexes in the 15 Gy group were still higher than those in the control group after 40 weeks. Azan staining showed a fibrotic pattern in the irradiated liver in the 30 Gy group only, but the expression levels of alpha smooth muscle actin (α-SMA) and transforming growth factor-beta 1 (TGF-β1) in both the 15 and 30 Gy groups were significantly higher than those in the control group (P < 0.05). There were differences in the pathological features of the irradiated livers between the 15 Gy and 30 Gy groups, but TGF-β1 and α-SMA expression patterns supported the gradual progression of radiation-induced liver fibrosis in both groups. These findings will be useful in the future development of protective drugs for radiation-induced liver injury. PMID:24566720

  15. Actions of juglone on energy metabolism in the rat liver

    SciTech Connect

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

    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

  16. Triglyceride kinetics, tissue lipoprotein lipase, and liver lipogenesis in septic rats

    SciTech Connect

    Lanza-Jacoby, S.; Tabares, A. )

    1990-04-01

    The mechanism for the development of hypertriglyceridemia during gram-negative sepsis was studied by examining liver production and clearance of very-low-density lipoprotein (VLDL) triglyceride (TG). To assess liver output and peripheral clearance the kinetics of VLDL-TG were determined by a constant iv infusion of (2-3H)glycerol-labeled VLDL. Clearance of VLDL-TG was also evaluated by measuring activities of lipoprotein lipase (LPL) in heart, soleus muscle, and adipose tissue from fasted control, fasted E. coli-treated, fed control, and fed E. coli-treated rats. Lewis inbred rats, 275-300 g, were made septic with 8 x 10(7) live E. coli colonies per 100 g body wt. Twenty-four hours after E. coli injection, serum TG, free fatty acids (FFA), and cholesterol of fasted E. coli-treated rats were elevated by 170, 76, and 16%, respectively. The elevation of serum TG may be attributed to the 67% decrease in clearance rate of VLDL-TG in fasted E. coli-treated rats compared with their fasted controls. The suppressed activities of LPL in adipose tissue, skeletal muscle, and heart were consistent with reduced clearance of TG. Secretion of VLDL-TG declined by 31% in livers of fasted E. coli-treated rats, which was accompanied by a twofold increase in the composition of liver TG. Rates of in vivo TG synthesis in livers of the fasted E. coli-treated rats were twofold higher than in those of fasted control rats. Decreased rate of TG appearance along with the increase in liver synthesis of TG contributed to the elevation of liver lipids in the fasted E. coli-treated rats.

  17. Protective effects of vitamin D3 against d-galactosamine-induced liver injury in rats.

    PubMed

    Colakoglu, Neriman; Kuloglu, Tuncay; Ozan, Enver; Kocaman, Nevin; Dabak, Durrin Ozlem; Parlak, Gozde

    2016-08-01

    In this study, we examined liver damage induced by d-galactosamine (d-GaIN) and the protective effects of vitamin D3 in relation to d-GaIN toxicity. Twenty Wistar albino rats were used in this study. The rats were divided into four groups. Group I rats were used as the control group. Group II rats were given a single intraperitoneal injection of d-GaIN. Group III rats were given a single intraperitoneal injection of d-GaIN, intramuscular vitamin D3 for five days. Group IV rats were given intramuscular vitamin D3 for five days. All of rats were euthanized by cervical decapitation on the fifth day of experiment. Upon completion of the experiment, a midsaggital incision was performed, and the livers of all rats were removed and fixed. The livers were processed to perform TUNEL technique and histochemical staining. During the microscope examination, we observed inflamatory cell infiltration, sinusoidal dilatation, and apoptotic bodies due to d-GaIN exposure. In addition, glycogen content of the group II hepatocytes was significantly decreased. Vitamin D3 treatment provided better structural apperance of the livers in group III. TUNEL positive cells were extremly pervasive in the group II livers. The study found group III TUNEL positive cells at a reduced rate in relation to group II due to vitamin D3 treatment. This findings indicate that d-GaIN causes inflamation in the liver. This inflamation triggers the apoptotic process gradually. Vitamin D3 has potency to decrease the severity of d-GaIN-caused structural liver damage. PMID:27291692

  18. METABOLOMIC EVALUATION OF RAT LIVER AND TESTIS TO CHARACTERIZE THE TOXICITY OF TRIAZOLE FUNGICIDES

    EPA Science Inventory

    The effects of two triazole fungicides, myclobutanil and triadimefon, on endogenous rat metabolite profiles in blood serum, liver, and testis was assessed using proton nuclear magnetic resonance (1H-NMR) spectroscopy. Adult male Sprague-Dawley rats were dosed daily by gavage for...

  19. Content of bioelements in the lungs and liver in rats with alimentary obesity.

    PubMed

    Trunova, V A; Sidorina, A V; Zvereva, V V; Churin, B V; Starkova, E V; Sorokoletov, D S

    2016-01-01

    The synchrotron radiation X-ray fluorescence technique (SRXRF) was applied to the determination of K, Ca, Mn, Fe, Cu, Zn, Se, Br, Rb, and Sr concentrations in the liver and lungs in Wistar rats. The animals in the experiment included (1) healthy rats, (2) rats with alimentary obesity (AO), and (3) rats with alimentary obesity that were being given zinc sulphate with water for a long time (АО+Zn). Each group was divided into two subgroups. The experiment with the first subgroup was terminated with the animals in the state of physiological hunger and subsequent retrieval of liver and lung tissue, while the animals of the second subgroup were sacrificed two hours after ingestion of lard. The rats in physiological hunger manifested intergroup differences in the content of the bioelements (BEs) neither in the liver nor in the lungs. The rats with AO, as compared with the healthy animals, demonstrated in physiological hunger redistribution of inter-element correlations (IECs), which is an indirect reflection of sustained metabolic disorder. Additional zinc in the rats' ration did not affect their body weight and the concentration of the BEs (including zinc) in the liver and the lungs. However, the IECs in the tissues of these animals in physiological hunger also changed. This redistribution differed from that in the rats with AO. The IECs soon after ingestion of lard also changed, which also reflects sustained changes in the metabolism in the animals. PMID:26653749

  20. Protective Effects of Norursodeoxycholic Acid Versus Ursodeoxycholic Acid on Thioacetamide-induced Rat Liver Fibrosis

    PubMed Central

    Buko, Vyacheslav U.; Lukivskaya, Oxana Y.; Naruta, Elena E.; Belonovskaya, Elena B.; Tauschel, Horst-Dietmar

    2014-01-01

    Background/objectives Effects of norursodeoxycholic acid (norUDCA) and ursodeoxycholic acid (UDCA) on liver fibrosis progression and liver fibrosis reversal in thioacetamide (TAA)-treated rats were studied. Methods Advanced liver fibrosis was induced by TAA treatment (200 mg/kg, i.p.) for 12 weeks. In the second experiment resolution of liver fibrosis was assessed after 8 weeks of TAA withdrawal. During 8 last weeks of each trial, fibrotic rats were daily administered with UDCA (80 mg/kg) and norUDCA (equimolar to 80 mg/kg of UDCA) by oral gavage. Liver fibrosis was assessed by Sirius red staining, liver hydroxyproline and serum fibrosis markers determination. Results The TAA treatment resulted in advanced fibrosis and increase in liver hydroxyproline content and serum fibrosis markers. These signs of fibrosis were less pronounced in rats after TAA withdrawal. Treatment with of norUDCA significantly decreased the total and relative liver hydroxyproline contents in rats with fibrosis reversal, whereas UDCA did not change these parameters. Both compounds decreased serum TGFβ and type IV collagen contents, whereas other serum markers did not differ from the placebo group. In the fibrosis progression model the square of connective tissue was decreased by norUDCA. Serum type IV collagen and procollagen III-NT contents in these experiments were lowered by both UDCA and norUDCA, whereas rest of serum fibrosis markers were diminished only by norUDCA. Conclusions Both norUDCA and UDCA showed therapeutic and prophylactic antifibrotic effect in rats with TAA-induced liver fibrosis. For most of tested parameters norUDCA was more effective than UDCA, especially in the experiment with liver fibrosis regression. PMID:25755576

  1. Reaction with DNA and mutagenic specificity of syn-benzo[g]chrysene 11,12-dihydrodiol 13,14-epoxide

    SciTech Connect

    Szeliga, J.; Page, J.E.; Ross, H.L.; Routledge, M.N.; Dipple, A.; Lee, H.; Harvey, R.G.; Hilton, B.D.

    1994-05-01

    The spectroscopic characterization of purine deoxyribonucleoside adducts derived from the fjord-region syn-benzo[g]chrysene 11,12-dihydrodiol 13,14-epoxide and the mutagenic specificity of the latter compound for the supF gene in the pSP189 shuttle vector are described. This dihydrodiol epoxide preferentially forms adducts with deoxyadenosine residues in DNA and is preferentially opened trans in reactions with DNA or with deoxyribonucleotides. In common with other fjord-region syn-dihydrodiol epoxides, the most frequently observed mutational changes were A {yields} T and G {yields} T changes. This hydrocarbon dihydrodiol epoxide is structurally similar to syn-benzo[c]phenanthrene 3,4-dihydrodiol 1,2-epoxide but has an additional benzene ring annelated distant from the reaction center. As anticipated, there were some common features in the chemistry and mutagenicities of these two compounds, but there were also substantive differences which indicate factors of importance in controlling reactions of these kinds of compounds with DNA. 38 refs., 11 figs., 2 tabs.

  2. Glycine decarboxylase in Rhodopseudomonas spheroides and in rat liver mitochondria

    PubMed Central

    Tait, G. H.

    1970-01-01

    1. Glycine decarboxylase and glycine–bicarbonate exchange activities were detected in extracts of Rhodopseudomonas spheroides and in rat liver mitochondria and their properties were studied. 2. The glycine decarboxylase activity from both sources is stimulated when glyoxylate is added to the assay system. 3. Several proteins participate in these reactions and a heat-stable low-molecular-weight protein was purified from both sources. 4. These enzyme activities increase markedly when R. spheroides is grown in the presence of glycine, glyoxylate, glycollate, oxalate or serine. 5. All the enzymes required to catalyse the conversion of glycine into acetyl-CoA via serine and pyruvate were detected in extracts of R. spheroides; of these glycine decarboxylase has the lowest activity. 6. The increase in the activity of glycine decarboxylase on illumination of R. spheroides in a medium containing glycine, and the greater increase when ATP is also present in the medium, probably accounts for the increased incorporation of the methylene carbon atom of glycine into fatty acids found previously under these conditions (Gajdos, Gajdos-Török, Gorchein, Neuberger & Tait, 1968). 7. The results are compared with those obtained by other workers on the glycine decarboxylase and glycine–bicarbonate exchange activities in other systems. PMID:5476725

  3. CHLORDANE AND HEPTACHLOR ARE METABOLIZED ENANTIOSELECTIVELY BY RAT LIVER MICROSOMES

    PubMed Central

    Kania-Korwel, Izabela; Lehmler, Hans-Joachim

    2013-01-01

    Chlordane, heptachlor and their metabolites are chiral persistent organic pollutants that undergo enantiomeric enrichment in the environment. This study investigated the enantioselective metabolism of both chlordane isomers and heptachlor, major components of technical chlordane, by liver microsomes prepared from male rats treated with corn oil (CO) or inducers of CYP2B (PB; Phenobarbital) and CYP3A enzymes (DX; dexamethasone), isoforms induced by chlordane treatment. The extent of the metabolism of all three parent compounds was dependent on the microsomal preparation used, and followed the rank order PB > DX > CO. The mass balances ranged from 49-130 % of the parent compound added to the microsomal incubations. Both cis- and trans-chlordane were enantioselectively metabolized to oxychlordane (EF=0.45-0.89) and 1,2-dichlorochlordene (EF=0.42-0.90). Heptachlor was metabolized enantioselectively, with heptachlor epoxide B (EF=0.44-0.54) being the only metabolite. Interestingly, the direction on the enrichment for oxychlordane, 1,2-dichlorochlordene and heptachlor epoxide differed depending on the microsomal preparation. These findings demonstrate that the direction and extent of the enantioselective metabolism of both chlordane isomers and heptachlor is P450 isoform-dependent and can be modulated by the induction of P450 enzymes. PMID:23799267

  4. The cellular transport of magnesium in rat liver.

    PubMed

    Wallach, S; Gamponia, P J; Ahmed, S A

    1970-12-01

    The bidirectional transport of Mg in rat liver was studied using slices labeled with (28)Mg in a closed two-compartment system under steady-state conditions. The influx (K(bs)) and efflux (K(sb)) transfer coefficients governing transport between the extracellular phase and a rapidly exchanging cell fraction were 0.074 and 0.019 per min, respectively. An increased extracellular concentration of Mg(++) caused a 30% decrease in K(bs) and a 31% increase in K(sb). A decreased extracellular Mg(++) had an opposite effect. At 0 degrees C, both transfer coefficients were reduced by 65%. Increased pH and NaCN increased transport, whereas Ca(++) reduced transport. Reduced pH, altered Na(+):K(+) ratio, Sr(++), glucose deletion, iodoacetate, ethanol, and lactate had no significant influence. Dinitrophenol reduced K(sb) but had no effect on K(bs). These data support the thesis that the intracellular concentration of Mg is in part regulated by a reciprocal change in the influx transfer coefficient and a parallel change in the efflux transfer coefficient in response to altered extracellular concentrations of Mg(++). The qualitative and quantitative similarities of Mg and Ca transport in this system suggest that Mg and Ca share a common transport mechanism which is primarily dependent upon the binding of these divalent cations to macromolecular ligands within the cell membrane or within the cell.

  5. Reconstitution of rat liver vasopressin receptors into phospholipid vesicles

    SciTech Connect

    Dickey, B.; Navarro, J.; Fishman, J.; Fine, R.

    1986-05-01

    Isolation and characterization of the hepatic vasopressin (V1) receptor has been hampered by the loss of vasopressin binding when the receptor is solubilized. An alternative to a soluble binding assay is reconstitution of solubilized receptors into phospholipid vesicles. They report here the initial reconstitution of solubilized vasopressin receptors. Rat liver microsomes were solubilized with 3% 3-((3-cholamido-propyl)dimethyl-ammonio)-1-propanesulfonate (CHAPS) in 20mM HEPES (pH 7.4). The solubilized protein was combined with an equal volume of 7% soybean phospholipids dissolved in 3% CHAPS. This solution was passed over a column of Sephadex G50 equilibrated with 30 mM HEPES, 5mM MgCl/sub 2/ (pH 7.4). Reconstituted vesicles containing the microsomal proteins were recovered in the void volume. Binding of (/sup 3/H)-Vasopressin to the reconstituted vesicles at pH 7.4 was 80% specific, saturable, reversible and required magnesium. Solubilization of microsomes in the presence of glycerol, prebound ligand, phospholipids or magnesium did not improve subsequent binding. This reconstitution procedure will allow examination of signal transduction mechanisms and may be used as a functional assay in isolating the receptor.

  6. Purification and some kinetic properties of rat liver glucosamine synthetase

    PubMed Central

    Winterburn, P. J.; Phelps, C. F.

    1971-01-01

    1. Glucosamine synthetase (l-glutamine–d-fructose 6-phosphate aminotransferase, EC 2.6.1.16) was purified about 300-fold from rat liver by two techniques. One procedure utilized the protective action of fructose 6-phosphate and gave a relatively stable preparation, the other yielded an unstable enzyme (half-life of about 20h), free of contaminant activities, on which kinetic experiments were performed. Although the properties of the two preparations showed slight differences, the unstabilized form could be converted into the stabilized form. 2. During preparation the enzyme retained its sensitivity to the feedback inhibitor, UDP-N-acetylglucosamine. 3. The reversibility of the enzyme-catalysed reaction could not be demonstrated. There was no apparent requirement for a cofactor. 4. The pH optimum was at 7.5, at which pH the reaction obeyed a Ping Pong Bi Bi rate equation. At pH values outside the range 6.9–7.6 and at temperatures below 29°C the velocity was described by an ordered Bi Bi rate equation. 5. The molecular weight of the enzyme, determined by two procedures, was 360000–400000. 6. The aminotransferase was unable to utilize ammonia as a substrate. PMID:4255955

  7. Disposition kinetics of diclofenac in the dual perfused rat liver.

    PubMed

    Sahin, Selma; Rowland, Malcolm

    2013-09-01

    This study investigates the hepatic disposition of diclofenac as a function of route of input: portal vein (PV) versus hepatic artery (HA) in the presence of its binding protein, albumin. The in situ dual perfused rat liver was performed using Krebs bicarbonate buffer containing human serum albumin (HSA, 0.25%-1%) at constant PV (12 mL/min) and HA (3 mL/min) flow rates. Bolus doses of [(14) C]-diclofenac and (125) I-labeled HSA were injected randomly into the HA or PV and then, after an appropriate interval, into the alternate vessel. Regardless of route of input and perfusion medium protein concentration, the hepatic outflow profile of diclofenac displayed a characteristic sharp peak followed by a slower eluting tail, indicating that its radial distribution is not instantaneous. Based on the estimated effective permeability-surface area product/blood flow ratio, hepatic uptake of diclofenac is governed by both perfusion and permeability. Fractional effluent recovery (F) increased as unbound diclofenac fraction in the perfusate decreased. Although no significant difference in hepatic clearance of diclofenac as a function of route of delivery at 0.5% and 1% HSA, it was demonstrable at 0.25% HSA (p < 0.001), when the extraction ratio is higher.

  8. Organization of connexons in isolated rat liver gap junctions.

    PubMed

    Gogol, E; Unwin, N

    1988-07-01

    Gap junction plaques from rat liver plasma membranes have been subjected to a range of detergent treatments in order to evaluate systematically the influence of different isolation procedures on their structure. The separation of the connexons was found to vary depending on the conditions used. In the absence of detergent the center-to-center separation of the connexons is, on average, approximately 90 A, and they are arranged on a hexagonal lattice so that the symmetry of the double-layered structure approximates to p6m in projection (or p622 in three-dimensions). Exposure to increasing concentration of detergent reduces the connexon separation to values below 80 A. More severe detergent treatment leads to disintegration of the gap junction plaques. Specimens with center-to-center separations smaller than 86 A show progressively larger deviation from p6m symmetry, seen as apparent rotations of the connexon assemblies within the crystal lattice. This reorganization occurs with both ice-embedded and negatively-stained specimens, using ionic or nonionic detergents, and therefore is probably a packing readjustment caused by depletion of intervening lipid molecules. PMID:3416022

  9. N2-Guanine specific transfer RNA methyltransferase I from rat liver and leukemic rat spleen*

    PubMed Central

    Kraus, Jan; Staehelin, Matthys

    1974-01-01

    An enzyme was purified from rat liver and leukemic rat spleen which methylates guanosine residues in tRNA to N2-methylguanosine. By sequence analysis of bulk E. coli tRNA methylated with crude extracts it was shown that the enzyme is responsible for about 50% of total m2G formed invitro. The extent of methylation of a number of homogenous tRNA species was measured using the purified enzyme from both sources. Among tested E. coli tRNAs only tRNAArg, tRNAPhe, and tRNAVal yielded significantly more m2G than the bulk tRNA. The Km for tRNAArg in the methylation reaction with enzymes from either tissue was 7.8 × 10−7 M as compared to the value 1 × 10−5 M obtained for the bulk tRNA. In a pancreatic RNase digest of bulk tRNA as well as of pure tRNAArg, tRNAPhe, and tRNAVal, A-m2G-Cp was found to be the only sequence methylated. Thus, the mammalian methyltransferase specifically recognizes the guanylate residue at position 10 from the 5′-end contained in a sequence (s4)U-A-G-Cp. Furthermore, there is no change between the enzyme from normal liver and leukemic spleen in the affinity for tRNA, the methylating capacity, and tRNA site and sequence recognition specificity. PMID:10793703

  10. Effect of dietary factors on mutagenesis, metabolism, and binding to DNA of benzo(a)pyrene and benzo(a)pyrene 7,8-dihydrodiol

    SciTech Connect

    Vance, R.E.

    1988-01-01

    Ellagic acid (EA), a naturally occurring plant phenol, at concentrations of 5 to 50 {mu}g/plate, inhibited rate liver S9 protein dependent benzo(a)pyrene (B(a)P)-induced mutagenesis in Salmonella typhimurium TA 100 by 30-81% and B(a)P 7,8-dihydrodiol (DHD)-induced mutagenesis by 29 to 75%. EA did not significantly affect the metabolism of B(a)P or B(a)P 7,8-DHD as determined by high performance liquid chromatographic analysis of the organosoluble fraction and by the quantification of water-soluble conjugates. At these concentrations EA inhibited the covalent binding of ({sup 3}H) B(a)P and ({sup 3}H) B(a)P 7,8-DHD metabolites to calf thymus DNA by 5 to 42% and 27 to 64%, respectively. Formation of benzo(a)pyrene 7,8-dihydrodiol-9,10-epoxide:deoxyguanosine (BPDE:dG) adducts was inhibited by 13 to 56% for B(a)P for B(a)P and 11 to 38% for B(a)P 7,8-DHD. These results suggest that the antimutagenic effect of EA and its inhibition of B(a)P and B(a)P 7,8-DHD metabolite-binding to DNA is not due to the inhibition of S9-mediated metabolism of these compounds. The inhibitory effect may be by previously described scavenging mechanism or by a DNA-affinity binding mechanism that prevents BPDE:DNA adduct formation.

  11. Liver and plasma levels of descarboxyprothrombin (PIVKA II) in vitamin K deficiency in rats.

    PubMed

    Harauchi, T; Takano, K; Matsuura, M; Yoshizaki, T

    1986-04-01

    Descarboxyprothrombin (PIVKA II) is a precursor of prothrombin without biological activity, and it increases with vitamin K deficiency. We studied the time course changes in liver and plasma levels of PIVKA II during the progress of vitamin K deficiency in rats. Good correlation was observed between liver PIVKA II and plasma PIVKA II and between liver or plasma PIVKA II and plasma prothrombin in experiments in which rats were fed a vitamin K-deficient diet. Feeding of a vitamin K-deficient diet or fasting caused marked increases in liver and plasma PIVKA II in male rats and a weaker response in female rats. Warfarin, a vitamin K antagonist, caused an abrupt increase in liver PIVKA II, but the increase in plasma PIVKA II was delayed about 3 hr. Plasma prothrombin decreased from about 30 min later. Factor VII decreased similarly to prothrombin, and changes in the prothrombin time and activated partial thromboplastin time were slower than the changes in these substances. Sex differences were not seen in these warfarin actions. These observations indicate that liver and plasma PIVKA II are sensitive markers of vitamin K deficiency in rats, and assay of PIVKA II can be useful for analyzing the action mechanism of drugs which influence blood coagulation.

  12. [Mutagenic Activity of Four Aminoazo Compounds with Different Carcinogenicity for Rat Liver in the Ames Test].

    PubMed

    Frolova, T S; Sinitsyna, O I; Kaledin, V I

    2015-01-01

    In this paper in the bacterial Ames test we compared the mutagenicity of four aminoazo compounds, previously studied by other researchers and used for activation of rat liver enzymes, with the carcinogenicity in the rat liver. It was found that in the Ames test they have mutagenic activity, however, this activity does not correlate quantitatively with rat sensitivity to their hepatocarcinogenic action. Thus, the most active carcinogen 3'-methyl-4-dimethylaminoazobenzene causes mutations almost 2.5 times less than weakly carcinogenic ortho-aminoazotoluene, and exactly the same number of mutations as non-carcinogenic N,N-diethyl-4-aminoazobenzene. PMID:26591610

  13. [Mutagenic Activity of Four Aminoazo Compounds with Different Carcinogenicity for Rat Liver in the Ames Test].

    PubMed

    Frolova, T S; Sinitsyna, O I; Kaledin, V I

    2015-01-01

    In this paper in the bacterial Ames test we compared the mutagenicity of four aminoazo compounds, previously studied by other researchers and used for activation of rat liver enzymes, with the carcinogenicity in the rat liver. It was found that in the Ames test they have mutagenic activity, however, this activity does not correlate quantitatively with rat sensitivity to their hepatocarcinogenic action. Thus, the most active carcinogen 3'-methyl-4-dimethylaminoazobenzene causes mutations almost 2.5 times less than weakly carcinogenic ortho-aminoazotoluene, and exactly the same number of mutations as non-carcinogenic N,N-diethyl-4-aminoazobenzene.

  14. Oxidative stress associated with pathological lesions in the liver of rats experimentally infected by Fasciola hepatica.

    PubMed

    Bottari, Nathieli B; Mendes, Ricardo E; Lucca, Neuber J; Schwertz, Claiton I; Henker, Luan C; Olsson, Débora C; Piva, Manoela M; Sangoi, Manuela; Campos, Luízi P; Moresco, Rafael N; Jaques, Jeandre A; Da silva, Aleksandro S

    2015-12-01

    The aim of this study was to analyze the antioxidant status and oxidative profile in serum and liver of rats experimentally infected with Fasciola hepatica and its relationship with pathological findings. Twenty-four rats were divided into two groups: group A consisted of 12 healthy rats and group B of 12 rats infected orally with 20 metacercaria of F. hepatica. At days 20 and 150 post-infection (PI), blood and liver samples of six animals from each group were collected. The protein oxidation (AOPP technique: advanced oxidation protein products) and antioxidants (FRAP technique: ferric reducing antioxidant power) levels were measured in serum and liver. Furthermore, nitrite/nitrate (NOx) levels and lipid peroxidation (TBARS technique: thiobarbituric acid reactive substances) were measured in liver. AOPP and FRAP levels were increased (P < 0.05) in serum and liver of infected animals in acute and chronic infection when compared with healthy animals. The same occurred with TBARS and NOx levels in the liver (P < 0.05). Histopathology revealed periportal fibrous hepatitis, composed of an abundant inflammatory infiltrate in portal spaces on infected animals, as well as bile duct hyperplasia. The results found seem to be related to the host free radical production demonstrated in serum samples and liver due to the parasite infection.

  15. Effects of extract derived from Eriobotrya japonica on liver function improvement in rats.

    PubMed

    Nishioka, Yutaka; Yoshioka, Saburo; Kusunose, Masahiko; Cui, Tailin; Hamada, Atuhide; Ono, Masahide; Miyamura, Mituhiko; Kyotani, Shojiro

    2002-08-01

    Eriobotrya japonica is considered a medicinal plant, and its leaves (Eriobotrya folia) have been used to treat skin diseases, as well as to relieve inflammation, pain, coughing, and sputa. In our evaluation of the pharmacological efficacy of the seed extracts, constituents of the seeds were found to contain the unsaturated fatty acids linolenic and linoleic acids and the sterol beta-sitosterol in the 70% EtOH and the MeOH extracts. The seed extracts were orally administered to rats with dimethylnitrosamine-induced hepatopathy, and blood L-asparate aminotransferase (AST) and L-alanine aminotransferase (ALT) levels, liver retinoid level, and hydroxyproline level were measured. Liver fibrosis rates calculated after Azan-Mallory staining and evaluation of the liver function-improving effects of extracts were showed that AST, ALT, and hydroxyproline levels and liver fibrosis rates were significantly lower, and retinoid levels were significantly higher in hepatopathic rats treated with 70% EtOH and MeOH extracts of the seed than in water-treated control rats. This suggests that the positive effect on liver function of the extracts varies depending on the extracting solvent used. 70% EtOH and MeOH extract of the seeds inhibited the development of liver fibrosis in hepatopathic rats, thus exhibiting potent improvement. The unsaturated linolenic and linoleic acids and the sterol beta-sitosterol contained in these extracts may also contribute to the improvement of liver function.

  16. Ameliorated effects of green tea extract on lead induced liver toxicity in rats.

    PubMed

    Mehana, E E; Meki, Abdel Raheim M A; Fazili, Khalid Majid

    2012-05-01

    In the present study, the effect of green tea extract (GTE) on lead induced toxicity was studied in Sprague-Dawley rats. Four groups of rats were used in the study. Lead and GTE was given orally to the rats with drinking water for 8 weeks. Lead concentration in the digested tissues of liver was detected using atomic absorption spectroscopy. The activities of glutathione-S-transferase (GST) and superoxide dismutase (SOD) were used as markers to evaluate the anti oxidant status of tissues. Lead exposure was found to attenuate the antioxidant potential of liver, which was however augmented when supplemented with green tea extract. Liver enzymes ALT, AST and ALP and serum protein determinations indicated the protective effects of green tea extract. Histopathological studies of liver revealed that supplementation of green tea extract resulted in mild degeneration and congestion of the blood vessels and an enhanced regenerative capacity.

  17. Inhibition of diethylnitrosamine-induced liver cancer in rats by Rhizoma paridis saponin.

    PubMed

    Liu, Jing; Man, Shuli; Li, Jing; Zhang, Yang; Meng, Xin; Gao, Wenyuan

    2016-09-01

    Rhizoma Paridis saponin (RPS) had been regarded as the main active components responsible for the anti-tumor effects of the herb Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. In the present research, we set up a rat model of diethylnitrosamine (DEN) induced hepatoma to evaluate antitumor effect of RPS. After 20 weeks treatment, rats were sacrificed to perform histopathological examinations, liver function tests, oxidative stress assays and so forth. As a result, DEN-induced hepatoma formation. RPS alleviated levels of liver injury through inhibiting liver tissues of malondialdehyde (MDA) and nitric oxide (NO) formation, increasing superoxide dismutases (SOD) production, and up-regulating expression of GST-α/μ/π in DEN-induced rats. All in all, RPS would be a potent agent inhibiting chemically induced liver cancer in the prospective application.

  18. Inhibition of diethylnitrosamine-induced liver cancer in rats by Rhizoma paridis saponin.

    PubMed

    Liu, Jing; Man, Shuli; Li, Jing; Zhang, Yang; Meng, Xin; Gao, Wenyuan

    2016-09-01

    Rhizoma Paridis saponin (RPS) had been regarded as the main active components responsible for the anti-tumor effects of the herb Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. In the present research, we set up a rat model of diethylnitrosamine (DEN) induced hepatoma to evaluate antitumor effect of RPS. After 20 weeks treatment, rats were sacrificed to perform histopathological examinations, liver function tests, oxidative stress assays and so forth. As a result, DEN-induced hepatoma formation. RPS alleviated levels of liver injury through inhibiting liver tissues of malondialdehyde (MDA) and nitric oxide (NO) formation, increasing superoxide dismutases (SOD) production, and up-regulating expression of GST-α/μ/π in DEN-induced rats. All in all, RPS would be a potent agent inhibiting chemically induced liver cancer in the prospective application. PMID:27451357

  19. Three dimensional culture of HepG2 liver cells on a rat decellularized liver matrix for pharmacological studies.

    PubMed

    Hussein, Kamal H; Park, Kyung M; Ghim, Jinn H; Yang, Se R; Woo, Heung M

    2016-02-01

    Three-dimensional in vitro tumor models are needed to obtain more information about drug behavior in tumors. The aim of this study is to establish a new model for hepatocellular carcinoma (HCC) using decellularized rat livers. After generating the rat liver scaffolds, HepG2 liver cancer cells were perfused via the portal vein and placed in a bioreactor for 10 days. Histology was performed to analyze cell distribution within the scaffolds. Function and tumor-related gene expression were examined by polymerase chain reaction (PCR). We evaluated the function of HepG2 cells grown on scaffolds in the presence of a well-known anti-cancer drug to investigate the potential application of our system for drug screening. The scaffolds were devoid of cellular materials and preserved extracellular matrix components. HepG2 cells grew well on the scaffolds. The PCR results showed that the cells maintained function and invasion ability at significantly higher levels than cells grown on two-dimensional (2-D) dishes or spheroids on Matrigel. Unlike the 2-D cultures, albumin secretion and alpha-fetoprotein expression in three-dimensional cultures were less susceptible to lower concentrations of the drug. Cells grown in scaffolds seemed to respond to the drug in an analogous manner to its known activity in vivo. These findings strengthen the potential use of rat liver scaffolds for screening HCC drugs.

  20. Antioxidant effect of hydroxytyrosol (DPE) and Mn2+ in liver of cadmium-intoxicated rats.

    PubMed

    Casalino, Elisabetta; Calzaretti, Giovanna; Sblano, Cesare; Landriscina, Vito; Felice Tecce, Mario; Landriscina, Clemente

    2002-12-01

    Liver TBARS formation in cadmium-intoxicated rats was completely reduced by administering a low amount of MnCl(2) (2 mg/kg b.w.) 1 h before intoxication. A similar antioxidant effect was first shown by hydroxytyrosol (2-(3,4-dihydroxyphenyl)ethanol, (DPE), a phenolic compound present in olive oil, given twice to rats (9 mg/kg b.w.) after cadmium administration. The antioxidant properties shown in vivo by both Mn(2+) and DPE were also active in vitro when rat liver microsomes were subjected to lipid peroxidation by cadmium or other prooxidant systems. The increase in liver glutathione concentrations occurring in cadmium-intoxicated rats, was also found, for the first time, 24 h after MnCl(2) administration. Unlike cadmium intoxication, which caused a higher formation of both glutathione and TBARS, Mn(2+) induced glutathione synthesis without any TBARS formation. The same situation was also observed when cadmium plus Mn(2+) or cadmium plus DPE was given to rats. Our data show that: (a). both DPE and low Mn(2+) concentrations may have an antioxidant effect in the livers of cadmium-intoxicated rats and (b). Mn(2+), like cadmium, induces liver glutathione synthesis and this effect is probably independent of TBARS formation. PMID:12458190

  1. Alterations in activation and deactivation of mutagens in aging rat liver.

    PubMed

    Masuda, M; Nukuzuma, C; Kazusaka, A; Fujita, S

    1995-09-01

    Age-associated alternations in activation and deactivation of benzo[a]pyrene (BP), furylfuramide (AF2), and 2-nitrofluorene (NF) in rat liver were investigated. A modified Ames mutagenicity test system used liver 9000 g supernatant (S-9) from male Fischer 344 rats aged 3, 6, 12, and 24 months fortified with NADPH generating system alone or together with cofactors of conjugating enzymes. The numbers of revertant colonies due to mutagenic activation of BP during preincubation were markedly high in young rats and decreased with aging. They were decreased by the addition of UDP-glucuronic acid (15 mM) or glutathione (30 mM), the cofactors of UDP-glucuronyl transferase and glutathione S-transferase, respectively, in the preincubation mixture. The difference in the BP activation by liver S-9 from different age groups almost disappeared by the addition of reduced glutathione. A direct mutagen, AF2, was not metabolized during preincubation in the absence of cofactors of conjugating enzymes, but detoxified up to about 50% by the addition of glutathione to the preincubation mixture containing liver S-9 from rats of any age group. Another direct mutagen, NF, was partly detoxified during preincubation by liver S-9 from 3-month-old rats more than by that from 24-month-old rats. It is suggested that incidence of chemical carcinogenesis may increase along with aging due to the altered xenobiotics metabolism. PMID:7671022

  2. Production of septal fibrosis of the liver by means of foreign protein injections into rats.

    PubMed

    Gotardo, Bruna Magalhães; Andrade, Rodrigo Guimarães; Oliveira, Ludmila Fernandes; Andrade, Zilton A

    2003-01-01

    Similarities and differences in antigenic humoral responses and electrophoretic patterns between Capillaria hepatica and pig-serum were investigated as a contribution to the understanding of hepatic fibrosis induced by the parenteral administration of foreign proteins. Only two out of 10 rats receiving repeated intraperitoneal injections of an extract of Capillaria hepatica-infected mouse liver presented septal hepatic fibrosis (20%). Under the same experimental conditions, 4 out of 9 rats (44.4%) developed septal fibrosis following whole pig-serum administration. Injections of normal mouse liver extracts did not result in hepatic fibrosis. Since a 100% septal fibrosis rate is observed in experimentally Capillaria hepatica-infected rats, it appeared that Capillaria hepatica products continuously released from inside the liver creates a much more effective fibrosis inducing mechanism than the parenteral administration of such factors. Thus, repeated peritoneal administration of a foreign protein to rats would not reveal the full fibrogenic potential it may have under natural conditions.

  3. Effect of sesame oil on serum and liver lipid profiles in the rat.

    PubMed

    Satchithanandam, S; Chanderbhan, R; Kharroubi, A T; Calvert, R J; Klurfeld, D; Tepper, S A; Kritchevsky, D

    1996-01-01

    In our previous study (Satchithanandam, S., Reicks, M., Calvert, R.J., Cassidy, M.M. and Kritchevsky, D. (1993) J. Nutr. 123, 1852-1858), we found that the absorption of lymphatic cholesterol by rats fed diets containing 24% sesame oil was about 50% less than that by rats fed the control diet containing no sesame oil. The effect of sesame oil on serum cholesterol levels was not determined at that time. In the present study, three groups of male Wistar rats (75-100 g) were fed a control diet or a diet containing 12 or 24% sesame oil. To increase serum cholesterol levels, 1% cholesterol and 0.5% cholic acid were added to each diet. After rats were fed for 4 weeks, total cholesterol, LDL-cholesterol, HDL-cholesterol, and triglyceride levels were measured in the serum. Liver weight and cholesterol and triglyceride levels were determined. Liver cholesterol levels were significantly lower in rats fed the 24% sesame oil diet, and the liver lipid level was significantly higher in the 24% sesame oil-fed group, compared with levels in the group fed the control diet. Liver weights and esterified cholesterol and liver triglyceride levels were not significantly different among the groups. Levels of serum total cholesterol and LDL-cholesterol were significantly lower in rats fed the 24% sesame oil diet, compared with levels in the control group. Serum triglyceride and HDL-cholesterol levels did not differ significantly among the groups. The mechanism by which a diet containing 24% sesame oil reduces levels of serum and liver cholesterol, liver LDL cholesterol, and liver lipids is not known. However, the high degree of unsaturation (85%) of sesame oil and the presence of linoleic acid may be important factors. PMID:8979168

  4. Expression patterns and action analysis of genes associated with drug-induced liver diseases during rat liver regeneration

    PubMed Central

    Ning, Qian-Ji; Qin, Shao-Wei; Xu, Cun-Shuan

    2006-01-01

    AIM: To study the action of the genes associated with drug-induced liver diseases at the gene transcriptional level during liver regeneration (LR) in rats. METHODS: The genes associated with drug-induced liver diseases were obtained by collecting the data from databases and literature, and the gene expression changes in the regenerating liver were checked by the Rat Genome 230 2.0 array. RESULTS: The initial and total expression numbers of genes occurring in phases of 0.5-4 h after partial hepatectomy (PH), 4-6 h after PH (G0/G1 transition), 6-66 h after PH (cell proliferation), 66-168 h after PH (cell differentiation and structure-function reconstruction) were 21, 3, 9, 2 and 21, 9, 19, 18, respectively. It is illustrated that the associated genes were mainly triggered at the initial stage of LR and worked at different phases. According to their expression similarity, these genes were classified into 5 types: only up-regulated (12 genes), predominantly up-regulated (4 genes), only down-regulated (11 genes), predominantly down-regulated (3 genes), and approximately up-/down-regulated (2 genes). The total times of their up- and down-expression were 130 and 79, respectively, demonstrating that expression of most of the genes was increased during LR, while a few decreased. The cell physiological and biochemical activities during LR were staggered according to the time relevance and were diverse and complicated in gene expression patterns. CONCLUSION: Drug metabolic capacity in regenerating liver was enhanced. Thirty-two genes play important roles during liver regeneration in rats. PMID:17109518

  5. Different doses of partial liver irradiation promotes hepatic regeneration in rat.

    PubMed

    Liu, Ying; Shi, Changzheng; Cui, Meng; Yang, Zhenhua; Gan, Danhui; Wang, Yiming

    2015-01-01

    The aim of this study is to investigate whether partial liver irradiation promotes hepatic regeneration in rat. Left-half liver of rat was irradiated to 10 Gy, and the Right-half to 0, 5, 10 and 15 Gy, respectively. Then, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) levels were evaluated on 0 day, 15-day, 30-day, 45-day and 60-day after liver irradiation. Next, the serum HGF, NF-κB and TGF-β1 levels were also analyzed on 60-day after liver irradiation. Lastly, the cyclinD1 protein expression was appraised by western blots on 60-day after liver irradiation. ALT, AST and ALP levels were reduced compared with that of controls. The serum HGF, NF-κB and TGF-β1 levels, and the cyclinD1 protein expression in liver irradiation group were increased compared with that of controls group. However, hepatic regeneration of higher dose-irradiated cirrhotic liver was triggered a more enhanced regeneration, compared with that of higher doses group. In summary, these results suggest that different doses of partial liver irradiation promotes hepatic regeneration in rat.

  6. Effects of ventromedial and lateral hypothalamic stimulation on chemically-induced liver injury in rats

    SciTech Connect

    Iwai, M.; Shimazu, T.

    1988-01-01

    The effects of hypothalamic stimulation on experimental liver injury induced by carbon tetrachloride (CCL/sub 4/) or dimethylnitrosamine (DMN) were studied in rats, by measuring plasma alanine amino-transferase (ALT) activity as an index of acute liver injury. Electrical stimulation of the ventromedial hypothalamus (VHM) in CCl/sub 4/-treated rats caused a marked increase in plasma ALT activity, accompanied by a significant decrease in ALT activity in the liver, although CCl4 treatment alone had no significant effect on plasma ALT activity. A similar effect of VHM stimulation on plasma ALT activity was observed in rats treated with DMN, another hepatotoxic chemical. No such exaggerated effect of VMH stimulation on plasma ALT activity was observed after stimulation of the lateral hypothalamic area (LH). Surgical sympathetic denervation of the liver greatly suppressed the increase in plasma ALT activity after CCl/sub 4/ injection and VMH stimulation. Measurement of regional blood flow indicated that VMH stimulation did not produce a significant change in blood flow to the liver. These results suggest that the VMH is involved in the progress of chemically-induced liver injury through activation of the sympathetic nerve, possibly by affecting liver metabolism more than the blood flow change to the liver.

  7. Post-dive ultrasound detection of gas in the liver of rats and scuba divers.

    PubMed

    L'abbate, Antonio; Marabotti, Claudio; Kusmic, Claudia; Pagliazzo, Antonino; Navari, Alessandro; Positano, Vincenzo; Palermo, Mario; Benassi, Antonio; Bedini, Remo

    2011-09-01

    In a previous study, we obtained histologic documentation of liver gas embolism in the rat model of rapid decompression. The aim of the study was to assess in the same model occurrence and time course of liver embolism using 2-D ultrasound imaging, and to explore by this means putative liver gas embolism in recreational scuba divers. Following 42 min compression at 7 ATA breathing air and 12 min decompression, eight surviving female rats were anesthetized and the liver imaged by ultrasound at 20 min intervals up to 120 min. A significant enhancement of echo signal was recorded from 60 to 120 min as compared to earlier post-decompression times. Enzymatic markers of liver damage (AST, ALT, and GGT) increased significantly at 24 h upon decompression. Twelve healthy experienced divers were studied basally and at 15-min intervals up to 60 min following a 30-min scuba dive at 30 msw depth. At 30 min upon surfacing echo images showed significant signal enhancement that progressed and reached plateau at 45 and 60 min. Total bilirubin at 24 h increased significantly (p = 0.02) with respect to basal values although within the reference range. In conclusion, 2-D ultrasound liver imaging allowed detection of gas embolism in the rat and defined the time course of gas accumulation. Its application to scuba divers revealed liver gas accumulation in all subjects in the absence of clear-cut evidence of liver damage or of any symptom. The clinical significance of our findings remains to be investigated.

  8. [Mitochondrial dysfunction and compensatory mechanisms in liver cells during acute carbon tetrachloride-induced rat intoxication].

    PubMed

    Zavodnik, I B

    2015-01-01

    Electron-transport chain and redox-balance of mitochondria are important targets that are damaged during intoxication. The aim of the present work was to estimate the role of impairments in cellular bioenergetic function in the development of liver damage during acute carbon tetrachloride intoxication in rats and to elucidate possible compensatory mechanisms. Acute CCl4-induced rat intoxication (0.8 g/kg or 4 g/kg) resulted in considerable impairments of respiratory and synthetic mitochondrial functions; their manifestations depended on the dose of the toxic agent and the duration of the intoxication increased and accompanied by complete uncoupling of oxidation and phosphorylation processes in liver mitochondria. The intoxication induced considerable liver damage and accumulation of NO in blood plasma and liver tissue. The changes of some parameters of liver mitochondrial functional activity demonstrate an oscillative pattern, reflecting compensatory mechanisms during intoxication that involved increased reduced glutathione level and enhanced succinate dehydrogenase activity. PMID:26716745

  9. The effects of ultraviolet C radiation on the ultrastructure of the liver cells of mole rats.

    PubMed

    Tekın, Saban; Türker, Hüseyin; Güven, Turan; Yel, Mustafa

    2016-01-01

    The aim of this study was to elucidate the ultrastructural changes in the liver cells of mole rats (Spalax leucodon) exposed to ultraviolet radiation (UVR). Thirteen mole rats used in this study were caught from nature. They were divided into four groups. The first group was separated as a control and was not given any radiation. The rest were exposed to ultraviolet C (UVC) radiation for 7, 14, and 21 days. The electron microscopic examinations revealed that significant ultrastructural changes occurred in the liver tissue. These changes were the reduction in cytoplasmic organelles, dilatation in rough endoplasmic reticulum, impairment of nucleus membrane, and broadened and vacuolated mitochondria in the cytoplasm. Also, UVC radiation caused significant changes in liver enzymes of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and gama-glutamiltransferase values. After long-term exposure to radiation, some excessive ultrastructural changes occurred. These results indicated that longer exposure to UVR would cause more ultrastructural effects on the liver cells and liver enzymes.

  10. Decellularization and Recellularization of Rat Livers With Hepatocytes and Endothelial Progenitor Cells.

    PubMed

    Zhou, Pengcheng; Huang, Yan; Guo, Yibing; Wang, Lei; Ling, Changchun; Guo, Qingsong; Wang, Yao; Zhu, Shajun; Fan, Xiangjun; Zhu, Mingyan; Huang, Hua; Lu, Yuhua; Wang, Zhiwei

    2016-03-01

    Whole-organ decellularization has been identified as a promising choice for tissue engineering. The aim of the present study was to engineer intact whole rat liver scaffolds and repopulate them with hepatocytes and endothelial progenitor cells (EPCs) in a bioreactor. Decellularized liver scaffolds were obtained by perfusing Triton X-100 with ammonium hydroxide. The architecture and composition of the original extracellular matrix were preserved, as confirmed by morphologic, histological, and immunolabeling methods. To determine biocompatibility, the scaffold was embedded in the subcutaneous adipose layer of the back of a heterologous animal to observe the infiltration of inflammatory cells. Hepatocytes were reseeded using a parenchymal injection method and cultured by continuous perfusion. EPCs were reseeded using a portal vein infusion method. Morphologic and functional examination showed that the hepatocytes and EPCs grew well in the scaffold. The present study describes an effective method of decellularization and recellularization of rat livers, providing the foundation for liver engineering and the development of bioartificial livers.

  11. [Mitochondrial dysfunction and compensatory mechanisms in liver cells during acute carbon tetrachloride-induced rat intoxication].

    PubMed

    Zavodnik, I B

    2015-01-01

    Electron-transport chain and redox-balance of mitochondria are important targets that are damaged during intoxication. The aim of the present work was to estimate the role of impairments in cellular bioenergetic function in the development of liver damage during acute carbon tetrachloride intoxication in rats and to elucidate possible compensatory mechanisms. Acute CCl4-induced rat intoxication (0.8 g/kg or 4 g/kg) resulted in considerable impairments of respiratory and synthetic mitochondrial functions; their manifestations depended on the dose of the toxic agent and the duration of the intoxication increased and accompanied by complete uncoupling of oxidation and phosphorylation processes in liver mitochondria. The intoxication induced considerable liver damage and accumulation of NO in blood plasma and liver tissue. The changes of some parameters of liver mitochondrial functional activity demonstrate an oscillative pattern, reflecting compensatory mechanisms during intoxication that involved increased reduced glutathione level and enhanced succinate dehydrogenase activity.

  12. Role of adenosine monophosphate in regulation of metabolic pathways of perfused rat liver

    PubMed Central

    Hunter, A. R.; Jefferson, L. S.

    1969-01-01

    1. By perfusion of rat livers with 3mm-AMP in the perfusion medium we obtain increased intracellular concentrations of AMP. 2. These high intracellular concentrations of AMP lead to an increased output of glucose and urea into the perfusion medium. 3. The increased output of glucose in livers from fed rats is brought about primarily by an AMP-stimulated breakdown of liver glycogen. In livers from starved rats the increase in glucose output is not as great, reflecting the low contents of glycogen in livers from starved rats. 4. AMP inhibits gluconeogenesis from lactate in perfused livers. In the presence of high concentrations of lactate, however, the counteracting effects of AMP to increase glycogenolysis and to inhibit gluconeogenesis result in little change in the net glucose output. 5. The increased urea output is brought about by increased breakdown of amino acids that are present in the perfusion medium. In livers from starved rats the overall urea production is much higher, indicating increased catabolism of amino acids and other nitrogenous substrates in the absence of carbohydrate substrates. 6. AMP causes an inhibition of incorporation of labelled precursors into protein and nucleic acid. This may result from increased catabolism of precursors of proteins and nucleic acids as reflected by the more rapid breakdown of nitrogenous compounds. In support of this hypothesis, cell-free systems for amino acid incorporation isolated from livers perfused with and without AMP are equally capable of supporting protein synthesis. 7. The labelling pattern of RNA in perfused livers corresponds very closely to those found by pulse-labelling in vivo. AMP in no way alters the qualitative nature of the labelling patterns. 8. We consider these results as supporting evidence for the role of the concentration ratio of AMP to ATP in controlling the metabolic pathways that lead to the formation of ATP. PMID:5774478

  13. Repeated treatment with furazolidone induces multiple cytochrome p450-related activities in chicken liver, but not in rat liver.

    PubMed

    Sasaki, Nobuo; Matumoto, Tomoyuki; Ikenaka, Yoshinori; Nakayama, Shouta M M; Ishizuka, Mayumi; Kazusaka, Akio; Fujita, Shoichi

    2013-11-01

    The nitrofuran antimicrobial agent, furazolidone (FZ), is still used in veterinary medicine in some countries in the Middle and Far Eastern countries. The present study aimed to investigate the effects of successive bolus doses of FZ and its metabolite 3-amino-2-oxazolidinone (AOZ) on cytochrome P450 (CYP)-related activities in the livers of rats and chickens. Female Wistar rats and white Leghorn chickens were orally administered FZ once a day for 4 consecutive days. FZ-treated chickens showed an increase in multiple CYP-related activities, however, rats treated with FZ did not show these changes. In chickens, treatment with FZ also induced production of microsomal CYP2C6-like apoprotein. The present study demonstrated that FZ caused a multiple-type induction of CYP-related activities in chickens, but not in rats.

  14. Repeated Treatment with Furazolidone Induces Multiple Cytochrome P450-Related Activities in Chicken Liver, but Not in Rat Liver

    PubMed Central

    SASAKI, Nobuo; MATUMOTO, Tomoyuki; IKENAKA, Yoshinori; NAKAYAMA, Shouta M. M.; ISHIZUKA, Mayumi; KAZUSAKA, Akio; FUJITA, Shoichi

    2013-01-01

    ABSTRACT The nitrofuran antimicrobial agent, furazolidone (FZ), is still used in veterinary medicine in some countries in the Middle and Far Eastern countries. The present study aimed to investigate the effects of successive bolus doses of FZ and its metabolite 3-amino-2-oxazolidinone (AOZ) on cytochrome P450 (CYP)-related activities in the livers of rats and chickens. Female Wistar rats and white Leghorn chickens were orally administered FZ once a day for 4 consecutive days. FZ-treated chickens showed an increase in multiple CYP-related activities, however, rats treated with FZ did not show these changes. In chickens, treatment with FZ also induced production of microsomal CYP2C6-like apoprotein. The present study demonstrated that FZ caused a multiple-type induction of CYP-related activities in chickens, but not in rats. PMID:23774039

  15. Dioxygenase- and monooxygenase-catalysed synthesis of cis-dihydrodiols, catechols, epoxides and other oxygenated products.

    PubMed

    Nolan, Louise C; O'Connor, Kevin E

    2008-11-01

    Oxidoreductases are an emerging class of biotechnologically relevant enzymes due to their regio- and stereo-specificity. The selective oxygenation of aromatic compounds by oxidoreductases has received much attention and a wide range of reactions have been documented using these enzymes from various microbial sources. This review gives an overview of various dioxygenase, monooxygenase and oxidase enzymes that have been manipulated for the synthesis of products such as cis-dihydrodiols, catechols, epoxides and other oxygenated products. The use of protein engineering and its advancement in the synthesis of recombinant enzymes is also discussed.

  16. EVALUATION OF BENZO[C]CHRYSENE DIHYDRODIOLS IN THE MORPHOLOGICAL CELL TRANSFORMATION OF MOUSE EMBRYO FIBROBLAST C3H10T1/2CL8 CELLS

    EPA Science Inventory

    EVALUATION OF BENZO[c]CHRYSENE DIHYDRODIOLS IN THE MORPHOLOGICAL CELL TRANSFORMATION OF MOUSE EMBRYO FIBROBLAST C3H10T?CL8 CELLS

    Abstract The morphological cell transforming activities of three dihydrodiols of benzo[c]chrysene (B[c]C), trans-B[c]C-7,8-diol, trans-B[c]C-9...

  17. Effect of Azadirachta indica (Neem) leaf aqueous extract on paracetamol-induced liver damage in rats.

    PubMed

    Bhanwra, S; Singh, J; Khosla, P

    2000-01-01

    The effect of aqueous leaf extract of Azadirachta indica (A. indica) was evaluated in paracetamol induced hepatotoxicity in rats. Liver necrosis was produced by administering single dose of paracetamol (2 g/kg, p.o.). The liver damage was evidenced by elevated levels of serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transpeptidase (gamma-GT) and by histopathological observations of liver sections. Aqueous A. indica leaf extract (500 mg/kg, p.o.) significantly (P < 0.01) reduced these elevated levels of AST, ALT and gamma-GT. Paracetamol induced liver necrosis was also found to be reduced as observed macroscopically and histologically. PMID:10919097

  18. The Mechanisms Underlying the Hypolipidaemic Effects of Grifola frondosa in the Liver of Rats

    PubMed Central

    Ding, Yinrun; Xiao, Chun; Wu, Qingping; Xie, Yizhen; Li, Xiangmin; Hu, Huiping; Li, Liangqiu

    2016-01-01

    The present study investigated the hypolipidaemic effects of Grifola frondosa and its regulation mechanism involved in lipid metabolism in liver of rats fed a high-cholesterol diet. The body weights and serum lipid levels of control rats, of hyperlipidaemic rats, and of hyperlipidaemic rats treated with oral G. frondosa were determined. mRNA expression and concentration of key lipid metabolism enzymes were investigated. Serum cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were markedly decreased in hyperlipidaemic rats treated with G. frondosa compared with untreated hyperlipidaemic rats. mRNA expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), acyl-coenzyme A: cholesterol acyltransferase (ACAT2), apolipoprotein B (ApoB), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC1) were significantly down-regulated, while expression of cholesterol 7-alpha-hydroxylase (CYP7A1) was significantly up-regulated in the livers of treated rats compared with untreated hyperlipidaemic rats. The concentrations of these enzymes also paralleled the observed changes in mRNA expression. Two-dimensional polyacrylamide gel electrophoresis (2-DE) and Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) were used to identify 20 proteins differentially expressed in livers of rats treated with G. frondosa compared with untreated hyperlipidemic rats. Of these 20 proteins, seven proteins were down-regulated, and 13 proteins were up-regulated. These findings indicate that the hypolipidaemic effects of G. frondosa reflected its modulation of key enzymes involved in cholesterol and triacylglycerol biosynthesis, absorption, and catabolic pathways. G. frondosa may exert anti-atherosclerotic effects by inhibiting LDL oxidation through down-regulation and up-regulating proteins expression in the liver of rats. Therefore, G. frondosa may produce both hypolipidaemic and anti-atherosclerotic effects, and potentially

  19. The Mechanisms Underlying the Hypolipidaemic Effects of Grifola frondosa in the Liver of Rats.

    PubMed

    Ding, Yinrun; Xiao, Chun; Wu, Qingping; Xie, Yizhen; Li, Xiangmin; Hu, Huiping; Li, Liangqiu

    2016-01-01

    The present study investigated the hypolipidaemic effects of Grifola frondosa and its regulation mechanism involved in lipid metabolism in liver of rats fed a high-cholesterol diet. The body weights and serum lipid levels of control rats, of hyperlipidaemic rats, and of hyperlipidaemic rats treated with oral G. frondosa were determined. mRNA expression and concentration of key lipid metabolism enzymes were investigated. Serum cholesterol, triacylglycerol, and low-density lipoprotein cholesterol levels were markedly decreased in hyperlipidaemic rats treated with G. frondosa compared with untreated hyperlipidaemic rats. mRNA expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), acyl-coenzyme A: cholesterol acyltransferase (ACAT2), apolipoprotein B (ApoB), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC1) were significantly down-regulated, while expression of cholesterol 7-alpha-hydroxylase (CYP7A1) was significantly up-regulated in the livers of treated rats compared with untreated hyperlipidaemic rats. The concentrations of these enzymes also paralleled the observed changes in mRNA expression. Two-dimensional polyacrylamide gel electrophoresis (2-DE) and Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF-MS) were used to identify 20 proteins differentially expressed in livers of rats treated with G. frondosa compared with untreated hyperlipidemic rats. Of these 20 proteins, seven proteins were down-regulated, and 13 proteins were up-regulated. These findings indicate that the hypolipidaemic effects of G. frondosa reflected its modulation of key enzymes involved in cholesterol and triacylglycerol biosynthesis, absorption, and catabolic pathways. G. frondosa may exert anti-atherosclerotic effects by inhibiting LDL oxidation through down-regulation and up-regulating proteins expression in the liver of rats. Therefore, G. frondosa may produce both hypolipidaemic and anti-atherosclerotic effects, and potentially

  20. Mechanism of enhanced lipid peroxidation in the liver of Long-Evans cinnamon (LEC) rats.

    PubMed

    Yamamoto, H; Hirose, K; Hayasaki, Y; Masuda, M; Kazusaka, A; Fujita, S

    1999-11-01

    The Long-Evans Cinnamon (LEC) rat is a mutant strain of rats that accumulate copper (Cu) in the liver in much the same way as individuals who suffer from Wilson's disease (WD) and has been suggested as a model for this disease. Lipid peroxidation (LPO) is considered to be involved in the toxic action of Cu in the livers of LEC rats. We investigated the mechanism of LPO in the livers of LEC rats showing apparent signs of hepatitis. Several-fold higher LPO levels were observed in post-mitochondrial supernatant (S-9) fraction of livers from hepatitic LEC rats than in those from Wistar rats. To mimic living cells, we introduced NADPH-generating system (NADPH-gs) into the S-9 incubation system. Thus was ensured a constant supply of NADPH to vital enzymes that may be directly or indirectly involved in the generation and/or elimination of reactive oxygen species (ROSs), such as glutathione reductase (GSSG-R), which require NADPH for their reactions. The levels of LPO in liver S-9 from hepatitic LEC rats were further increased by incubating liver S-9 at 37 degrees C in the presence of NADPH-gs. This increase was inhibited by EDTA, butylated hydroxytoluene (BHT), and catalase (CAT), suggesting that some metal, most likely the accumulated Cu, and ROSs derived from hydrogen peroxide (H2O2) are involved in the increased levels of LPO in the livers of hepatitic LEC rats. The requirement of NADPH-gs for enhanced LPO in the livers of hepatitic LEC rats indicates the consumption of NADPH during reactions leading to LPO. It is known that H2O2, and consequently hydroxyl radical are generated during Cu-catalyzed glutathione (GSH) oxidation. The cyclic regeneration of GSH from GSSG by NADPH-dependent GSSG-R in the presence of NADPH-gs may cause sustained generation of hydroxyl radical in the presence of excess free Cu. The generation of H2O2 in S-9 fraction of livers from hepatitic LEC rats was observed to be significantly higher than that in S-9 fraction of livers from non

  1. Metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes.

    PubMed

    Li, Yan; Wu, Linan; Gu, Yuan; Si, Duanyun; Liu, Changxiao

    2014-06-01

    Aildenafil, 1-{[3-(6, 7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [4, 3-d] primidin-5-yl)-4-ethoxyphenyl] sulfonyl}-cis-3, 5-dimethylpiperazine, a phosphodiesterase type V enzyme inhibitor (PDE5I), is under development for treatment of erectile dysfunction (ED). The purpose of this study was to elucidate metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes. Thirty-one phase I metabolites have been found by LTQ/Orbitrap hybrid mass spectrometry in rat urine, faeces, and bile after oral administration. Major biotransformation pathways of aildenafil included N-dealkylation of the piperazine ring, hydroxylation and dehydrogenation, aliphatic hydroxylation and loss of alkyl group of piperazine ring. Minor pathways involved hydroxylation on the phenyl ring, pyrazole N-demethylation, O-deethylation, loss of piperazine ring (cleavage of N-S bond) and dehydrogenation on the piperazine ring. Similar metabolic pathways of aildenafil were observed in the incubations of liver microsomes from mouse, rat, and dog as well as from human. The depletion rate of parent drug in mouse and rat liver microsomes was significantly different from that in human liver microsomes. The cytochrome P450 reaction phenotyping analysis was conducted using isozyme-specific inhibitors. The results indicated that CYP3A was the main isoenzyme involved in oxidative metabolism of aildenafil. Overall, these in vitro and in vivo findings should provide valuable information on possible metabolic behaviours of aildenafil in humans. PMID:24311535

  2. Metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes.

    PubMed

    Li, Yan; Wu, Linan; Gu, Yuan; Si, Duanyun; Liu, Changxiao

    2014-06-01

    Aildenafil, 1-{[3-(6, 7-dihydro-1-methyl-7-oxo-3-propyl-1H-pyrazolo [4, 3-d] primidin-5-yl)-4-ethoxyphenyl] sulfonyl}-cis-3, 5-dimethylpiperazine, a phosphodiesterase type V enzyme inhibitor (PDE5I), is under development for treatment of erectile dysfunction (ED). The purpose of this study was to elucidate metabolism of aildenafil in vivo in rats and in vitro in mouse, rat, dog, and human liver microsomes. Thirty-one phase I metabolites have been found by LTQ/Orbitrap hybrid mass spectrometry in rat urine, faeces, and bile after oral administration. Major biotransformation pathways of aildenafil included N-dealkylation of the piperazine ring, hydroxylation and dehydrogenation, aliphatic hydroxylation and loss of alkyl group of piperazine ring. Minor pathways involved hydroxylation on the phenyl ring, pyrazole N-demethylation, O-deethylation, loss of piperazine ring (cleavage of N-S bond) and dehydrogenation on the piperazine ring. Similar metabolic pathways of aildenafil were observed in the incubations of liver microsomes from mouse, rat, and dog as well as from human. The depletion rate of parent drug in mouse and rat liver microsomes was significantly different from that in human liver microsomes. The cytochrome P450 reaction phenotyping analysis was conducted using isozyme-specific inhibitors. The results indicated that CYP3A was the main isoenzyme involved in oxidative metabolism of aildenafil. Overall, these in vitro and in vivo findings should provide valuable information on possible metabolic behaviours of aildenafil in humans.

  3. Maternal saturated-fat-rich diet promotes leptin resistance in fetal liver lipid catabolism and programs lipid homeostasis impairments in the liver of rat offspring.

    PubMed

    Mazzucco, María Belén; Fornes, Daiana; Capobianco, Evangelina; Higa, Romina; Jawerbaum, Alicia; White, Verónica

    2016-01-01

    We aimed to analyze if an overload of saturated fat in maternal diet induced lipid metabolic impairments in livers from rat fetuses that persist in the offspring and to identify potential mechanisms involving fetal leptin resistance. Female rats were fed either a diet enriched in 25% of saturated fat (SFD rats) or a regular diet (controls). Fetuses of 21days of gestation and offspring of 21 and 140days of age were obtained and plasma and liver were kept for further analysis. Livers from a group of control and SFD fetuses were cultured in the presence or absence of leptin. Leptin or vehicle was administered to control fetuses during the last days of gestation and, on day 21, fetal livers and plasma were obtained. Lipid levels were assessed by thin-layer chromatography and mRNA gene expression of CPT1, ACO and PPARα by RT-PCR. Liver lipid levels were increased and CPT1 and ACO were down-regulated in fetuses and offspring from SFD rats compared to controls. After the culture with leptin, control fetal livers showed increased ACO and CPT1 expression and decreased lipid levels, while fetal livers from SFD rats showed no changes. Fetal administration of leptin induced a decrease in ACO and no changes in CPT1 expression. In summary, our results suggest that a saturated fat overload in maternal diet induces fetal leptin resistance in liver lipid catabolism, which might be contributing to liver lipid alterations that are sustained in the offspring.

  4. Ameliorative effect of Partysmart in rat model of alcoholic liver disease.

    PubMed

    Gopumadhavan, S; Rafiq, Mohammed; Azeemuddin, M; Mitra, S K

    2008-02-01

    Present study was designed to investigate the effect of polyherbal formulation PartySmart in experimental model of alcoholic liver disease in male Wistar strain rats. Alcohol plus fish oil were administered to animals for 8 weeks to induce liver injury. PartySmart was administered at doses of 250 and 500 mg/kg body weight. After 8 weeks, parameters such as liver weight, liver function serum markers alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) and lipid peroxidation were studied. Livers from all the groups were subjected for histological evaluation. Treatment with PartySmart at the dose of 500 mg/kg body weight showed significant reduction in the levels of serum ALT, AST and ALP with a decrease in liver weight as compared to ethanol-fed rats. A significant decrease was also observed in malondialdehyde levels following treatment with PartySmart at 500 mg/kg body weight. Histological profile of liver tissue in PartySmart-treated animals showed lesser vacuolar degeneration and intactness of hepatic architecture along with improved glycogen deposition as demonstrated by PAS staining. PartySmart ameliorated alcohol-induced liver injury by preventing cell membrane disturbances, reduction of oxidative stress by free radical scavenging and antioxidant activity and normalization of altered intracellular redox status. Thus, PartySmart can be beneficial in the treatment of alcohol-induced liver damage. PMID:18335812

  5. The cellular transport of calcium in rat liver.

    PubMed

    Wallach, S; Reizenstein, D L; Bellavia, J V

    1966-03-01

    The bidirectional transport of calcium in rat liver was studied using slices labeled with Ca(47) in a closed two compartment system. Steady-state conditions were observed with influx and efflux transfer coefficients of 0.070 and 0.018 per minute, respectively. The rapidly exchanging cell fraction of calcium existed at a concentration three times higher than the average cell concentration of calcium and occupied cell loci comprising less than 25% of the cell mass, suggesting that calcium associated with the cell membranes, nuclei, and mitochondria participated in the rapidly exchanging fraction. At pH 7.4 and 377deg;C, the influx transfer coefficient was 25% above the steady-state condition and accumulation of calcium by the slices occurred. Studies of the effects of varied physical and chemical conditions revealed that the influx transfer coefficient was increased by elevated pH, strontium, certain metabolic inhibitors, and 2 mM concentrations of cyclic adenosinemonophosphate and adenosinetriphosphate. The influx transfer coefficient was decreased by reduced temperature, decreased pH, magnesium, and 10 mM adenosinetriphosphate. The efflux transfer coefficient was increased by elevated pH, strontium, iodoacetate, and adenosinetriphosphate, and was decreased by reduced temperature and by N-ethylmaleimide. These data support the thesis that cell transport of calcium is accomplished by the attachment of calcium atoms to the cell surface and transport through the plasma membrane bound to either specific carriers or to membrane constituents. Conditions which change the affinities, capacities, and mobilities of plasma membrane ligands that bind calcium or cause extracellular chelation of calcium are capable of altering the rate of calcium transport.

  6. D-Lactate transport and metabolism in rat liver mitochondria.

    PubMed Central

    de Bari, Lidia; Atlante, Anna; Guaragnella, Nicoletta; Principato, Giovanni; Passarella, Salvatore

    2002-01-01

    In the present study we investigated whether isolated rat liver mitochondria can take up and metabolize D-lactate. We found the following: (1) externally added D-lactate causes oxygen uptake by mitochondria [P/O ratio (the ratio of mol of ATP synthesized to mol of oxygen atoms reduced to water during oxidative phosphorylation)=2] and membrane potential (Delta(psi)) generation in processes that are rotenone-insensitive, but inhibited by antimycin A and cyanide, and proton release from coupled mitochondria inhibited by alpha-cyanocinnamate, but not by phenylsuccinate; (2) the activity of the putative flavoprotein (D-lactate dehydrogenase) was detected in inside-out submitochondrial particles, but not in mitochondria and mitoplasts, as it is localized in the matrix phase of the mitochondrial inner membrane; (3) three novel separate translocators exist to mediate D-lactate traffic across the mitochondrial inner membrane: the D-lactate/H(+) symporter, which was investigated by measuring fluorimetrically the rate of endogenous flavin reduction, the D-lactate/oxoacid antiporter (which mediates both the D-lactate/pyruvate and D-lactate/oxaloacetate exchanges) and D-lactate/malate antiporter studied by monitoring photometrically the appearance of the D-lactate counteranions outside mitochondria. The D-lactate translocators, in the light of their different inhibition profiles separate from the monocarboxylate carrier, were found to differ from each other in the V(max) values and in the inhibition and pH profiles and were shown to regulate mitochondrial D-lactate metabolism in vitro. The D-lactate translocators and the D-lactate dehydrogenase could account for the removal of the toxic methylglyoxal from cytosol, as well as for D-lactate-dependent gluconeogenesis. PMID:11955284

  7. [Regulation of autophagy on dendritic cells during rat liver regeneration by IPA].

    PubMed

    Qiwen, Wang; Wei, Jin; Cuifang, Chang; Cunshuan, Xu

    2015-03-01

    To understand the mechanism underlying autophagy in regulating dendritic cells during rat liver regeneration, we used the method of percoll density gradient centrifugation combined with immunomagnetic bead to isolate dendritic cells, the Rat Genome 230 2.0 Array to determine the expression changes of autophagy-related genes, and Ingenuity Pathway Analysis 9.0 (IPA) to determine the autophagy activities. The results indicated that LC3, BECN1, ATG7 and SQSTM1 genes had significant expression changes during rat liver regeneration. There were 593 genes related to autophagy, among which 210 genes were identified as significant. We also showed that the activity of autophagy was enhanced in the priming phase and teminal phase of liver regeneration, weakened in the proliferative stage by comparative analysis method of IPA. The autophagy-related physiological activities mainly included RNA expression, RNA transcription, cell differentiation and proliferation, involving in PPARα/RXRα activation, acute phase response signaling, TREM1 signaling, IL-6 signaling, IL-8 signaling and IL-1 signaling, whose activities were increased or decreased in liver regeneration. Cluster analysis found that P53 and AMPK signaling participated in the regulation of dendritic cells autophagy, with AMPK signaling in the priming phase of liver regeneration, and both signaling pathways in the terminal phase. We conclude that dendritic cells autophagy played an important role in initiation of the immune response in priming phase and depletion of dendritic cells in late phase during rat liver regeneration.

  8. Biochemical changes and oxidative stress induced by zearalenone in the liver of pregnant rats.

    PubMed

    Zhou, C; Zhang, Y; Yin, S; Jia, Z; Shan, A

    2015-01-01

    The aim of the present research was to examine the toxic influence of different doses of zearalenone (ZEN) on the liver, especially oxidative stress induced by ZEN on the liver. A total of 48 pregnant Sprague-Dawley rats were randomly assigned into 4 treatments groups with 12 animals in each. The rats were fed with a normal diet treated with 0 mg/kg (control), 50 mg/kg (treatment 1), 100 mg/kg (treatment 2), or 150 mg/kg (treatment 3) ZEN in feed on gestation days (GDs) 0-7 and then all the rats were fed with a normal diet on GDs 8-20. The experimental period lasted 21 days. The results showed that exposure to ZEN induced increase in aspartate amino transferase, alanine aminotransferase, and alkaline phosphatase activities and decrease in total protein and albumin content in a dose-dependent manner and also induce decrease in superoxide dismutase and glutathione peroxidase activities and increase in malondialdehyde content in a dose-dependent manner in the serum and the liver. The increased transcription of cytochrome P450 2E1 (CYP2E1) was detected in the liver after exposure to ZEN. These results suggested that ZEN not only caused damage in the liver of pregnant rats in a dose-dependent manner but also induced the messenger RNA expression of CYP2E1 in the liver. PMID:24717317

  9. Bisphenol A glucuronide/sulfate diconjugate in perfused liver of rats

    PubMed Central

    INOUE, Hiroki; KEMANAI, Shino; SANO, Chie; KATO, Seiyu; YOKOTA, Hiroshi; IWANO, Hidetomo

    2016-01-01

    In isolated hepatocytes, the environmental estrogen bisphenol A (BPA) is metabolized into a mono-glucuronide and a glucuronide/sulfate diconjugate. Little is known about the fate of the diconjugate in the liver. The present study focused on the metabolism and dispostion of BPA diconjugate in the liver using a perfusion method. In Sprague-Dawley rats, BPA (15,150 or 1,500 nmol) was applied into the liver. In male rats, the infused BPA was conjugated to both glucuronide and a diconjugate during passage through the liver. The diconjugate was observed at high-dose application of the substrate. In female rats, the chemical was conjugated almost exclusively to the glucuronide in all doses utilized in this study. In both the male and female rats, the resultant metabolites were preferentially excreted into the bile. These results suggest that BPA is conjugated primarily to mono-glucuronide in rat liver; and that in males, diconjugate production occurs under conditions of high-dose exposure to BPA. PMID:26782136

  10. Endotoxin-induced liver necrosis and intravascular coagulation in rats enhanced by portacaval collateral circulation.

    PubMed Central

    Liehr, H; Grün, M; Thiel, H; Brunswig, D; Rasenack, U

    1975-01-01

    The effects of intravenously administered endotoxin on the hepatic and systemic circulation as well as on the coagulation system were evaluated in normal rats (n = 26), in rats with experimental portal hypertension (n = 15), and in rats with portacaval anastomosis (n = 22). Endotoxin (1-5 mg/kg) in the normal rat leads to a prompt increase of transaminase activity and to a hyperdynamic circulation with a consequent increase in the total hepatic blood flow. In a later phase (6 h postoperatively) the hepatic artery dilated with a consequent hepatic arterial hyperperfusion. The coagulation system was affected with signs of consumption coagulopathy. In the rats with portal hypertension and portacaval collaterals as well as in those with portacaval anastomosis, the endotoxin injection resulted in acute liver necrosis within 12 to 15 hours. The hepatic artery became overdilated with a cardiac output fraction of 25% (normal 5-5%). Blood extravasates and thrombi, rich in fibrin, were detected in the liver. It is suggested that this exaggeration of the endotoxin effect was due to an impaired clearance function of the reticuloendothelial system, probably as consequence of portacaval collateral circulation. It is concluded that endotoxins (1) damage the liver even in a normal organism; (2) are potent to induce acute liver necrosis, if the reticuloendothelial system is altered; (3) have to be taken into consideration as contribution to the pathogenesis of acute as well as chronic liver diseases. Images Fig. 3 Fig. 4 PMID:1150113

  11. Protective effect of black tea on integral membrane proteins in rat liver.

    PubMed

    Szachowicz-Petelska, Barbara; Skrzydlewska, Elżbieta; Figaszewski, Zbigniew

    2013-01-01

    Ethanol intoxication is accompanied by oxidative stress formation. Consequently, it leads to disturbances in cellular metabolism that can alter the structure and function of cell membrane components. Black tea displays antioxidant properties, protects membrane phospholipids and may protect integral membrane proteins. In the present study, we examined whether black tea induces changes in the liver integral membrane proteins of 12-months old rats chronically intoxicated with ethanol. To estimate qualitatively and quantitatively the levels of the liver integral membrane proteins, the proteins were selectively hydrolyzed by trypsin, the obtained peptides were resolved by HPLC and the levels of specific amino acids within the individual peptides were determined. All of the obtained peptides contained phenylalanine (Phe), cysteine (Cys) and lysine (Lys). Compared to the control group, rats in the ethanol intoxication group showed decreased liver levels of integral membrane proteins as well as fewer trypsin-hydrolyzed peptides and amino acids in the hydrolyzed peptides. Administration of black tea to ethanol-intoxicated rats partially protected proteins against the structural changes caused by ethanol. Black tea prevented decreases in the levels of cysteine (in about 90% of cases), lysine (in about 60% of cases), phenylalanine (in about 70% of cases) and examined peptides (in about 60% of cases). The liver protein level was higher (by about 18%) in rats who received black tea and ethanol than in those who received ethanol alone. In conclusion, black tea partially protects the composition and level of rat liver cell integral membrane proteins against changes caused by ethanol intoxication.

  12. Glycyrrhizin ameliorates metabolic syndrome-induced liver damage in experimental rat model.

    PubMed

    Sil, Rajarshi; Ray, Doel; Chakraborti, Abhay Sankar

    2015-11-01

    Glycyrrhizin, a major constituent of licorice (Glycyrrhiza glabra) root, has been reported to ameliorate insulin resistance, hyperglycemia, dyslipidemia, and obesity in rats with metabolic syndrome. Liver dysfunction is associated with this syndrome. The objective of this study is to investigate the effect of glycyrrhizin treatment on metabolic syndrome-induced liver damage. After induction of metabolic syndrome in rats by high fructose (60%) diet for 6 weeks, the rats were treated with glycyrrhizin (50 mg/kg body weight, single intra-peritoneal injection). After 2 weeks of treatment, rats were sacrificed to collect blood samples and liver tissues. Compared to normal, elevated activities of serum alanine transaminase, alkaline phosphatase and aspartate transaminase, increased levels of liver advanced glycation end products, reactive oxygen species, lipid peroxidation, protein carbonyl, protein kinase Cα, NADPH oxidase-2, and decreased glutathione cycle components established liver damage and oxidative stress in fructose-fed rats. Activation of nuclear factor κB, mitogen-activated protein kinase pathways as well as signals from mitochondria were found to be involved in liver cell apoptosis. Increased levels of cyclooxygenase-2, tumor necrosis factor, and interleukin-12 proteins suggested hepatic inflammation. Metabolic syndrome caused hepatic DNA damage and poly-ADP ribose polymerase cleavage. Fluorescence-activated cell sorting using annexin V/propidium iodide staining confirmed the apoptotic hepatic cell death. Histology of liver tissue also supported the experimental findings. Treatment with glycyrrhizin reduced oxidative stress, hepatic inflammation, and apoptotic cell death in fructose-fed rats. The results suggest that glycyrrhizin possesses therapeutic potential against hepatocellular damage in metabolic syndrome. PMID:26400710

  13. [Effect of pyruvate, threonine, and phosphoethanolamine on acetaldehyde metabolism in rats with toxic liver injury].

    PubMed

    Pron'ko, P S; Satanovskaia, V I; Gorenshteĭn, B I; Kuz'mich, A B; Pyzhik, T N

    2002-01-01

    Pyruvate dehydrogenase, threonine aldolase and phosphoethanolamine lyase can produce acetaldehyde during normal metabolism. We studied the effect of loading with the substrates of these enzymes (pyruvate, 500 mg/kg, i.p., threonine 500 mg/kg, i.p., and phosphoethanolamine, 230 mg/kg, i.p.) on the blood concentrations of endogenous acetaldehyde and ethanol and the activities of enzymes producing and oxidizing acetaldehyde in the liver of normal rats and rats with liver injury provoked by chronic carbon tetrachloride (CCl4) treatment (0.2 ml i.p. per rat, 2 times a week during 4 weeks). Blood was collected before the treatment and then 30 min and 1 h following the administration of the substrates to intact and CCl4-treated rats. Endogenous acetaldehyde and ethanol were determined by headspace GC. The CCl4 treatment resulted in decreased liver alcohol dehydrogenase and aldehyde dehydrogenase activities and a significant elevation of liver endogenous ehtanol and a clear tendency to enhance blood acetaldehyde levels. Pyruvate increased blood endogenous acetaldehyde in CCl4-treated animals and endogenous ethanol--in the control group of animals. Threonine elevated endogenous acetaldehyde in normal rats. Phosphoethanolamine increased endogenous ethanol in the intact and CCl4 groups. At the same time, in CCl4-treated rats pyruvate administration increased the liver pyruvate dehydrogenase, threonine decreased threonine aldolase, whereas phosphoethanolamine decreased phosphoethanolamine lyase. Thus, the CCl4 effect on blood endogenous acetaldehyde and ethanol may be mediated through decreased liver ALDH and ADH activities. Liver injury promotes the accumulation of acetaldehyde, derived from physiological sources, including the degration of pyruvate and threonine by decreased acetaldehyde oxidation.

  14. Species differences in the handling of lysosomotropic metals and Triton WR 1339 by rat and Chinese hamster liver.

    PubMed

    Seidel, A; Heumann, H G; Sütterlin, U; Wiener, M; Haffner, H

    1985-05-01

    The study was undertaken in order to understand the reasons for the distinct differences in the elimination rate of lanthanides and transuranium elements from the liver of different mammalian species. The binding of monomeric 239Pu in livers of rats and Chinese hamsters was analyzed by density gradient centrifugation and electrophoresis. It was concluded that this nuclide is initially bound to lysosomes in liver of rats and Chinese hamsters. The influence of Triton WR 1339 (TWR) on the density of lysosomal marker enzymes from rat and Chinese hamster liver at day 4 was very similar for both animal species but the TWR induced shift persisted in Chinese hamsters up to day 60 whereas in rat liver the lysosomal density increased again with time. Electron microscopic inspection confirmed the similarity of the initial reaction of hepatocyte lysosomes. However, after 60 to 70 days typical TWR induced "tritosomes" were absent from rat hepatocytes but could be found regularly in hepatocytes from Chinese hamsters. The elimination rate of 3H-activity from liver injection of 3H-TWR was lower in Chinese hamsters than in rats. It was concluded that the differences in elimination rate of lanthanides and transuranium elements from liver of various mammalian species and the differences observed after TWR injection might reflect differences in the composition or function of the lysosomal system in the livers of different mammalian species. With respect to the transport of certain heavy metals the rat liver is not a reliable model for human liver. PMID:4029172

  15. Cilostazol improves hepatic blood perfusion, microcirculation, and liver regeneration after major hepatectomy in rats.

    PubMed

    von Heesen, Maximilian; Dold, Stefan; Müller, Simon; Scheuer, Claudia; Kollmar, Otto; Schilling, Martin K; Menger, Michael D; Moussavian, Mohammed R

    2015-06-01

    Major hepatectomy or small-for-size liver transplantation may result in postoperative liver failure. So far, no treatment is available to improve liver regeneration. Herein, we studied whether cilostazol, a selective phosphodiesterase III inhibitor, is capable of improving liver regeneration after major hepatectomy. Sprague-Dawley rats (n = 74) were treated with cilostazol (5 mg/kg daily) or a glucose solution and underwent either 70% liver resection or a sham operation. Before and after surgery, hepatic arterial and portal venous blood flow and hepatic microvascular perfusion were analyzed. Liver morphology, function, and regeneration were studied with histology, immunohistochemistry, western blotting, and bile excretion analysis. Cilostazol significantly increased hepatic blood flow and microcirculation before and after hepatectomy in comparison with sham-operated controls. This was associated with an elevation of hepatic vascular endothelial growth factor expression, an increase of hepatocellular proliferation, and an acceleration of liver regeneration. Furthermore, cilostazol protected the tissue of the remnant liver as indicated by an attenuation of hepatocellular disintegration. In conclusion, cilostazol increases hepatic blood perfusion, microcirculation, and liver regeneration after a major hepatectomy. Thus, cilostazol may represent a novel strategy to reduce the rate of liver failure after both extended hepatectomy and small-for-size liver transplantation.

  16. Effect of the Human Amniotic Membrane on Liver Regeneration in Rats

    PubMed Central

    Sipahi, Mesut; Şahin, Sevinç; Arslan, Ergin; Börekci, Hasan; Metin, Bayram; Cantürk, Nuh Zafer

    2015-01-01

    Introduction. Operations are performed for broader liver surgery indications for a better understanding of hepatic anatomy/physiology and developments in operation technology. Surgery can cure some patients with liver metastasis of some tumors. Nevertheless, postoperative liver failure is the most feared complication causing mortality in patients who have undergone excision of a large liver mass. The human amniotic membrane has regenerative effects. Thus, we investigated the effects of the human amniotic membrane on regeneration of the resected liver. Methods. Twenty female Wistar albino rats were divided into control and experimental groups and underwent a 70% hepatectomy. The human amniotic membrane was placed over the residual liver in the experimental group. Relative liver weight, histopathological features, and biochemical parameters were assessed on postoperative day 3. Results. Total protein and albumin levels were significantly lower in the experimental group than in the control group. No difference in relative liver weight was observed between the groups. Hepatocyte mitotic count was significantly higher in the experimental group than in the control group. Hepatic steatosis was detected in the experimental group. Conclusion. Applying the amniotic membrane to residual liver adversely affected liver regeneration. However, mesenchymal stem cell research has the potential to accelerate liver regeneration investigations. PMID:26457000

  17. A mode of action for induction of liver tumors by Pyrethrins in the rat

    SciTech Connect

    Price, Roger J.; Walters, David G.; Finch, John M.; Gabriel, Karl L.; Capen, Charles C.; Osimitz, Thomas G. . E-mail: tom@sciencestrategies.com; Lake, Brian G.

    2007-01-15

    High doses of Pyrethrins produce liver tumors in female rats. To elucidate the mode of action for tumor formation, the hepatic effects of Pyrethrins have been investigated. Male Sprague-Dawley CD rats were fed diets containing 0 (control) and 8000 ppm Pyrethrins and female rats' diets containing 0, 100, 3000 and 8000 ppm Pyrethrins for periods of 7, 14 and 42 days and 42 days followed by 42 days of reversal. As a positive control, rats were also fed diets containing 1200-1558 ppm sodium Phenobarbital (NaPB) for 7 and 14 days. The treatment of male rats with 8000 ppm Pyrethrins, female rats with 3000 and 8000 ppm Pyrethrins and both sexes with NaPB resulted in increased liver weights, which were associated with hepatocyte hypertrophy. Hepatocyte replicative DNA synthesis was also increased by treatment with Pyrethrins and NaPB. The treatment of male and female rats with Pyrethrins and NaPB produced significant increases in hepatic microsomal cytochrome P450 (CYP) content and a marked induction of CYP2B-dependent 7-pentoxyresorufin O-depentylase and testosterone 16{beta}-hydroxylase activities. Significant increases were also observed in CYP3A-dependent testosterone 6{beta}-hydroxylase activity. The hepatic effects of Pyrethrins were dose-dependent in female rats with 100 ppm being a no effect level and on cessation of treatment were reversible in both sexes. This study demonstrates that Pyrethrins are mitogenic CYP2B form inducers in rat liver. The mode of action for Pyrethrins-induced rat liver tumor formation appears to be similar to that of NaPB and some other non-genotoxic CYP2B inducers of hepatic xenobiotic metabolism.

  18. Sipa1l1 is an early biomarker of liver fibrosis in CCl4-treated rats

    PubMed Central

    Marfà, Santiago; Morales-Ruiz, Manuel; Oró, Denise; Ribera, Jordi; Fernández-Varo, Guillermo; Jiménez, Wladimiro

    2016-01-01

    ABSTRACT At present, several procedures are used for staging liver fibrosis. However, these methods may involve clinical complications and/or present diagnostic uncertainty mainly in the early stages of the disease. Thus, this study was designed to unveil new non-invasive biomarkers of liver fibrosis in an in vivo model of fibrosis/cirrhosis induction by CCl4 inhalation by using a label-free quantitative LC-MS/MS approach. We analyzed 94 serum samples from adult Wistar rats with different degrees of liver fibrosis and 36 control rats. Firstly, serum samples from 18 CCl4-treated rats were clustered into three different groups according to the severity of hepatic and the serum proteome was characterized by label-free LC-MS/MS. Furthermore, three different pooled serum samples obtained from 16 control Wistar rats were also analyzed. Based on the proteomic data obtained, we performed a multivariate analysis which displayed three main cell signaling pathways altered in fibrosis. In cirrhosis, more biological imbalances were detected as well as multi-organ alterations. In addition, hemopexin and signal-induced proliferation-associated 1 like 1 (SIPA1L1) were selected as potential serum markers of liver fibrogenesis among all the analyzed proteins. The results were validated by ELISA in an independent group of 76 fibrotic/cirrhotic rats and 20 controls which confirmed SIPA1L1 as a potential non-invasive biomarker of liver fibrosis. In particular, SIPA1L1 showed a clear diminution in serum samples from fibrotic/cirrhotic rats and a great accuracy at identifying early fibrotic stages. In conclusion, the proteomic analysis of serum samples from CCl4-treated rats has enabled the identification of SIPA1L1 as a non-invasive marker of early liver fibrosis. PMID:27230648

  19. Ameliorative Effects of Pomegranate Peel Extract against Dietary-Induced Nonalcoholic Fatty Liver in Rats.

    PubMed

    Al-Shaaibi, Siham N K; Waly, Mostafa I; Al-Subhi, Lyutha; Tageldin, Mohamed H; Al-Balushi, Nada M; Rahman, Mohammad S

    2016-03-01

    Non-alcoholic fatty liver disease (NAFLD) is caused by fat accumulation and is associated with oxidative stress. In this study, we investigated the potential protective effect of pomegranate (Punica granatum L.) peel extract (PPE) against oxidative stress in the liver of rats with NAFLD. Sprague-Dawley rats were fed a high fat diet (HFD), 20% corn oil, or palm oil for 8 weeks in the presence or absence of PPE. The control group was fed a basal diet. The progression of NAFLD was evaluated histologically and by measuring liver enzymes (alanine transaminase and aspartate transaminase), serum lipids (triglycerides and total cholesterol), and oxidative stress markers. The HFD feeding increased the body weight and caused NAFLD, liver steatosis, hyperlipidemia, oxidative stress, and elevated liver enzymes. Administration of PPE ameliorated the hepatic morphology, reduced body weight, improved liver enzymes, and inhibited lipogenesis. Furthermore, PPE enhanced the cellular redox status in the liver tissue of rats with NAFLD. Our findings suggest that PPE could improve HFD-induced NAFLD via abolishment of hepatic oxidative damage and hyperlipidemia. PPE might be considered as a potential lead material in the treatment of NAFLD and obesity through the modulation of lipid metabolism. PMID:27069901

  20. Ameliorative Effects of Pomegranate Peel Extract against Dietary-Induced Nonalcoholic Fatty Liver in Rats

    PubMed Central

    Al-Shaaibi, Siham N. K.; Waly, Mostafa I.; Al-Subhi, Lyutha; Tageldin, Mohamed H.; Al-Balushi, Nada M.; Rahman, Mohammad S.

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) is caused by fat accumulation and is associated with oxidative stress. In this study, we investigated the potential protective effect of pomegranate (Punica granatum L.) peel extract (PPE) against oxidative stress in the liver of rats with NAFLD. Sprague-Dawley rats were fed a high fat diet (HFD), 20% corn oil, or palm oil for 8 weeks in the presence or absence of PPE. The control group was fed a basal diet. The progression of NAFLD was evaluated histologically and by measuring liver enzymes (alanine transaminase and aspartate transaminase), serum lipids (triglycerides and total cholesterol), and oxidative stress markers. The HFD feeding increased the body weight and caused NAFLD, liver steatosis, hyperlipidemia, oxidative stress, and elevated liver enzymes. Administration of PPE ameliorated the hepatic morphology, reduced body weight, improved liver enzymes, and inhibited lipogenesis. Furthermore, PPE enhanced the cellular redox status in the liver tissue of rats with NAFLD. Our findings suggest that PPE could improve HFD-induced NAFLD via abolishment of hepatic oxidative damage and hyperlipidemia. PPE might be considered as a potential lead material in the treatment of NAFLD and obesity through the modulation of lipid metabolism. PMID:27069901

  1. Methanobactin reverses acute liver failure in a rat model of Wilson disease

    PubMed Central

    Lichtmannegger, Josef; Leitzinger, Christin; Wimmer, Ralf; Schmitt, Sabine; Schulz, Sabine; Eberhagen, Carola; Rieder, Tamara; Janik, Dirk; Neff, Frauke; Straub, Beate K.; Schirmacher, Peter; DiSpirito, Alan A.; Bandow, Nathan; Baral, Bipin S.; Flatley, Andrew; Kremmer, Elisabeth; Denk, Gerald; Reiter, Florian P.; Hohenester, Simon; Eckardt-Schupp, Friedericke; Dencher, Norbert A.; Sauer, Vanessa; Niemietz, Christoph; Schmidt, Hartmut H.J.; Merle, Uta; Gotthardt, Daniel Nils; Kroemer, Guido; Weiss, Karl Heinz

    2016-01-01

    In Wilson disease (WD), functional loss of ATPase copper-transporting β (ATP7B) impairs biliary copper excretion, leading to excessive copper accumulation in the liver and fulminant hepatitis. Current US Food and Drug Administration– and European Medicines Agency–approved pharmacological treatments usually fail to restore copper homeostasis in patients with WD who have progressed to acute liver failure, leaving liver transplantation as the only viable treatment option. Here, we investigated the therapeutic utility of methanobactin (MB), a peptide produced by Methylosinus trichosporium OB3b, which has an exceptionally high affinity for copper. We demonstrated that ATP7B-deficient rats recapitulate WD-associated phenotypes, including hepatic copper accumulation, liver damage, and mitochondrial impairment. Short-term treatment of these rats with MB efficiently reversed mitochondrial impairment and liver damage in the acute stages of liver copper accumulation compared with that seen in untreated ATP7B-deficient rats. This beneficial effect was associated with depletion of copper from hepatocyte mitochondria. Moreover, MB treatment prevented hepatocyte death, subsequent liver failure, and death in the rodent model. These results suggest that MB has potential as a therapeutic agent for the treatment of acute WD. PMID:27322060

  2. Methanobactin reverses acute liver failure in a rat model of Wilson disease.

    PubMed

    Lichtmannegger, Josef; Leitzinger, Christin; Wimmer, Ralf; Schmitt, Sabine; Schulz, Sabine; Kabiri, Yaschar; Eberhagen, Carola; Rieder, Tamara; Janik, Dirk; Neff, Frauke; Straub, Beate K; Schirmacher, Peter; DiSpirito, Alan A; Bandow, Nathan; Baral, Bipin S; Flatley, Andrew; Kremmer, Elisabeth; Denk, Gerald; Reiter, Florian P; Hohenester, Simon; Eckardt-Schupp, Friedericke; Dencher, Norbert A; Adamski, Jerzy; Sauer, Vanessa; Niemietz, Christoph; Schmidt, Hartmut H J; Merle, Uta; Gotthardt, Daniel Nils; Kroemer, Guido; Weiss, Karl Heinz; Zischka, Hans

    2016-07-01

    In Wilson disease (WD), functional loss of ATPase copper-transporting β (ATP7B) impairs biliary copper excretion, leading to excessive copper accumulation in the liver and fulminant hepatitis. Current US Food and Drug Administration- and European Medicines Agency-approved pharmacological treatments usually fail to restore copper homeostasis in patients with WD who have progressed to acute liver failure, leaving liver transplantation as the only viable treatment option. Here, we investigated the therapeutic utility of methanobactin (MB), a peptide produced by Methylosinus trichosporium OB3b, which has an exceptionally high affinity for copper. We demonstrated that ATP7B-deficient rats recapitulate WD-associated phenotypes, including hepatic copper accumulation, liver damage, and mitochondrial impairment. Short-term treatment of these rats with MB efficiently reversed mitochondrial impairment and liver damage in the acute stages of liver copper accumulation compared with that seen in untreated ATP7B-deficient rats. This beneficial effect was associated with depletion of copper from hepatocyte mitochondria. Moreover, MB treatment prevented hepatocyte death, subsequent liver failure, and death in the rodent model. These results suggest that MB has potential as a therapeutic agent for the treatment of acute WD. PMID:27322060

  3. Data on differentially expressed microRNAs in the liver between nonalcoholic fatty liver disease and normal Wistar rat using Solexa sequencing.

    PubMed

    Zhang, Deqing; Wang, Yuqian; Ji, Zhibin; Wang, Zhonghua

    2016-09-01

    The dataset includes data from the Solexa sequencing reported in our paper: "Identification and differential expression of microRNAs associated with fat deposition in the liver of Wistar rats with nonalcoholic fatty liver disease" [1]. The data collected include small RNAs and microRNAs in liver tissue from high glucose-induced NAFLD Wistar rats, using normal Wistar rats as their negative controls. 6 small RNA libraries were constructed and the expression profiles were compared between the two groups. Here we describe in detail how the data, deposited in the Gene Expression Omnibus (GEO) with the accession number GEO: GSE68411, was generated including the basic analysis. PMID:27331102

  4. Lysosomal acid lipase deficiency in rats: Lipid analyses and lipase activities in liver and spleen

    SciTech Connect

    Kuriyama, M.; Yoshida, H.; Suzuki, M.; Fujiyama, J.; Igata, A. )

    1990-09-01

    We report the biological characterization of an animal model of a genetic lipid storage disease analogous to human Wolman's disease. Affected rats accumulated cholesteryl esters (13.3-fold), free cholesterol (2.8-fold), and triglycerides (5.4-fold) in the liver, as well as cholesteryl esters (2.5-fold) and free cholesterol (1.33-fold) in the spleen. Triglycerides did not accumulate, and the levels actually decreased in the spleen. Analysis of the fatty acid composition of the cholesteryl esters and triglycerides showed high percentages of linoleic acid (18:2) and arachidonic acid (20:4) in both organs, especially in the liver. No accumulation of phospholipids, neutral glycosphingolipids, or gangliosides was found in the affected rats. Acid lipase activity for (14C)triolein, (14C)cholesteryl oleate, and 4-methyl-umbelliferyl oleate was deficient in both the liver and spleen of affected rats. Lipase activity at neutral pH was normal in both liver and spleen. Heterozygous rats showed intermediate utilization of these substrates in both organs at levels between those for affected rats and those for normal controls, although they did not accumulate any lipids. These data suggest that these rats represent an animal counterpart of Wolman's disease in humans.

  5. Nonalcoholic Fatty Liver Disease Progression in Rats is Accelerated by Splenic Regulation of Liver PTEN/AKT

    PubMed Central

    Wang, Ziming; Li, Naishu; Wang, Biao; Lin, Jianhua

    2015-01-01

    Background/Aim: The spleen has been reported to participate in the development of nonalcoholic fatty liver disease (NAFLD), but the mechanism has not been fully characterized. This study aims to elucidate how the spleen affects the development of NAFLD in a rat model. Materials and Methods: Following either splenectomy or sham operation, male Sprague–Dawley (SD) rats were fed a high-fat diet to drive the development of NAFLD; animals fed a normal diet were used as controls. Two months after surgery, livers and blood samples were collected. Serum lipids were measured; liver histology, phosphatase and tensin homologue deleted on chromosome 10 (PTEN) gene expression, and the ratio of pAkt/Akt were determined. Results: Splenectomy increased serum lipids, except triglyceride (TG) and high-density lipoprotein (HDL), in animals fed either a high-fat or normal diet. Furthermore, splenectomy significantly accelerated hepatic steatosis. Western blot analysis and real-time polymerase chain reaction showed splenectomy induced significant downregulation of PTEN expression and a high ratio of pAkt/Akt in the livers. Conclusions: The spleen appears to play a role in the development of NAFLD, via a mechanism involving downregulation of hepatic PTEN expression. PMID:26228367

  6. Correlation between liver cell necrosis and circulating alanine aminotransferase after ischaemia/reperfusion injuries in the rat liver.

    PubMed

    Knudsen, Anders R; Andersen, Kasper J; Hamilton-Dutoit, Stephen; Nyengaard, Jens R; Mortensen, Frank V

    2016-04-01

    Circulating liver enzymes such as alanine transaminase are often used as markers of hepatocellular damage. Ischaemia/reperfusion (I/R) injury is an inevitable consequence of prolonged liver ischaemia. The aim of this study was to examine the correlation between liver enzymes and volume of liver cell necrosis after ischaemia/reperfusion injuries, using design-unbiased stereological methods. Forty-seven male Wistar rats were subjected to 1 h of partial liver ischaemia, followed by either 4 or 24 h of reperfusion. Within each group, one-third of animals were subjected to ischaemic preconditioning and one-third to ischaemic postconditioning. At the end of reperfusion, blood and liver samples were collected for analysis. The volume of necrotic liver tissue was subsequently correlated to circulating markers of I/R injury. Correlation between histological findings and circulating markers was performed using Pearson's correlation coefficient. Alanine transferase peaked after 4 h of reperfusion; however, at this time-point, only mild necrosis was observed, with a Pearson's correlation coefficient of 0.663 (P = 0.001). After 24 h of reperfusion, alanine aminotransferase was found to be highly correlated to the degree of hepatocellular necrosis R = 0.836 (P = 0.000). Furthermore, alkaline phosphatase (R = 0.806) and α-2-macroglobulin (R = 0.655) levels were also correlated with the degree of necrosis. We show for the first time that there is a close correlation between the volume of hepatocellular necrosis and alanine aminotransferase levels in a model of I/R injury. This is especially apparent after 24 h of reperfusion. Similarly, increased levels of alkaline phosphatase and α-2-macroglobulin are correlated to the volume of liver necrosis. PMID:27292534

  7. Umbilical cord-derived mesenchymal stem cells alleviate liver fibrosis in rats

    PubMed Central

    Chai, Ning-Li; Zhang, Xiao-Bin; Chen, Si-Wen; Fan, Ke-Xing; Linghu, En-Qiang

    2016-01-01

    AIM: To evaluate the efficacy of umbilical cord-derived mesenchymal stem cells (UC-MSCs) transplantation in the treatment of liver fibrosis. METHODS: Cultured human UC-MSCs were isolated and transfused into rats with liver fibrosis induced by dimethylnitrosamine (DMN). The effects of UC-MSCs transfusion on liver fibrosis were then evaluated by histopathology; serum interleukin (IL)-4 and IL-10 levels were also measured. Furthermore, Kupffer cells (KCs) in fibrotic livers were isolated and cultured to analyze their phenotype. Moreover, UC-MSCs were co-cultured with KCs in vitro to assess the effects of UC-MSCs on KCs’ phenotype, and IL-4 and IL-10 levels were measured in cell culture supernatants. Finally, UC-MSCs and KCs were cultured in the presence of IL-4 antibodies to block the effects of this cytokine, followed by phenotypical analysis of KCs. RESULTS: UC-MSCs transfused into rats were recruited by the injured liver and alleviated liver fibrosis, increasing serum IL-4 and IL-10 levels. Interestingly, UC-MSCs promoted mobilization of KCs not only in fibrotic livers, but also in vitro. Co-culture of UC-MSCs with KCs resulted in increased production of IL-4 and IL-10. The addition of IL-4 antibodies into the co-culture system resulted in decreased KC mobilization. CONCLUSION: UC-MSCs could increase IL-4 and promote mobilization of KCs both in vitro and in vivo, subsequently alleviating the liver fibrosis induced by DMN. PMID:27468195

  8. [Cyclosporin, toxicity and efficacy in rejection of liver allografts in the rat].

    PubMed

    Settaf, A; Gugenheim, J; Lahlou, M K; Gigou, M; Capron-Laudereau, M; Charpentier, B; Reynes, M; Lokiec, F; Bismuth, H

    1989-01-01

    52 orthotopic liver transplants were performed in DA to lewis rat strain combination, in order to appreciate cyclosporine toxicity, and efficacy at doses of 10 mg/kg day (G II) and 20 mg/kg/day (GIII) compared to liver allografts in DA/lewis rats. The first signs of cyclosporine hepatotoxicity are biological (increased plasma level of bilirubine and transaminase) that were noticed at the dose of 20 mg/kg/day. Histological signs (cells inclusion, hepatocytic necrosis) appeared late and were less constant as well as difficult to assert creatinine plasma level was the best reflect of cyclosporine nephrotoxicity. Renal toxicity was practically constant at the dose of 20 mg/kg/day. In spite of renal and hepatic toxicity, cyclosporin by itself, allows the abolition of the acute rejection of liver allografts in the rat.

  9. Selective permeability of rat liver mitochondria to purified aspartate aminotransferases in vitro.

    PubMed Central

    Marra, E; Doonan, S; Saccone, C; Quagliariello, E

    1977-01-01

    1. A method was devised to allow determination of intramitochondrial aspartate amino-transferase activity in suspensions of intact mitochondria. 2. Addition of purified rat liver mitochondrial aspartate aminotransferase to suspensions of rat liver mitochondria caused an apparent increase in the intramitochondrial enzyme activity. No increase was observed when the mitochondria were preincubated with the purified cytoplasmic isoenzyme. 3. These results suggest that mitochondrial aspartate aminotransferase, but not the cytoplasmic isoenzyme, is able to pass from solution into the matrix of intact rat liver mitochondria in vitro. 4. This system may provide a model for studies of the little-understood processes by which cytoplasmically synthesized components are incorporated into mitochondria in vivo. PMID:883959

  10. Hepatoprotective activity of bacoside A against N-nitrosodiethylamine-induced liver toxicity in adult rats.

    PubMed

    Janani, Panneerselvam; Sivakumari, Kanakarajan; Parthasarathy, Chandrakesan

    2009-10-01

    N-Nitrosodiethylamine (DEN) is a notorious carcinogen, present in many environmental factors. DEN induces oxidative stress and cellular injury due to enhanced generation of reactive oxygen species; free radical scavengers protect the membranes from DEN-induced damage. The present study was designed to evaluate the protective effect of bacoside A (the active principle isolated from Bacopa monniera Linn.) on carcinogen-induced damage in rat liver. Adult male albino rats were pretreated with 15 mg/kg body weight/day of bacoside A orally (for 14 days) and then intoxicated with single necrogenic dose of N-nitrosodiethylamine (200 mg/kg bodyweight, intraperitonially) and maintained for 7 days. The liver weight, lipid peroxidation (LPO), and activity of serum marker enzymes (aspartate transaminases, alanine transaminases, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transpeptidase) were markedly increased in carcinogen-administered rats, whereas the activities of marker enzymes were near normal in bacoside A-pretreated rats. Activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutatione-S-transferase, and reduced glutathione) in liver also decreased in carcinogen-administered rats, which were significantly elevated in bacoside A-pretreated rats. It is concluded that pretreatment of bacoside A prevents the elevation of LPO and activity of serum marker enzymes and maintains the antioxidant system and thus protects the rats from DEN-induced hepatotoxicity.

  11. The effect of avocado oils on some liver characteristics in growing rats.

    PubMed

    Werman, M J; Mokady, S; Neeman, I; Auslaender, L; Zeidler, A

    1989-05-01

    The effects of various avocado oils on some liver characteristics were studied in growing rats. The rats were fed diets containing 10% (w/w) avocado oil for 4 wk. In comparison with rats fed refined oil obtained from cored fruit by centrifugal separation, rats fed unrefined avocado oil obtained by solvent extraction from the intact fruit, or refined avocado oil containing avocado-seed oil, showed significant growth inhibition, an increase in the amount of hepatic lipids (identified as steatosis by histopathological examination), and a decrease in levels of triglycerides in blood. Rats fed the refined oil containing unsaponifiable material prepared from unrefined oil from the intact fruit showed similar responses. Fatty livers were not induced by feeding rats unrefined avocado oil obtained from intact fruit by centrifugal separation, although a significant decrease in blood triglycerides was observed. There were no significant differences between groups in serum total protein, albumin or bilirubin content or in alanine aminotransferase activity. However, serum alkaline phosphatase activity was increased in rats fed the seed oil, the unrefined solvent-extracted oil from intact fruit, or the unsaponifiables, and aspartate aminotransferase activity was significantly increased in the group fed avocado-seed oil. These data suggest that consumption of avocado oil extracted from intact fruit may cause changes in liver metabolism.

  12. Cilostazol attenuates cholestatic liver injury and its complications in common bile duct ligated rats.

    PubMed

    Abdel Kawy, Hala S

    2015-04-01

    Cilostazol is a phosphodiesterase III inhibitor increases adenosine 3', 5'-cyclic monophosphate (cyclic AMP) level which inhibits hepatic stellate cell activation. Its pharmacological effects include vasodilation, inhibition of vascular smooth muscle cell growth, inhibition of platelet activation and aggregation. The aim of the current study was to determine the effects of early administration of low dose cilostazol on cholestatic liver injury induced by common bile duct ligation (CBDL) in rat. Male Wistar rats (180-200g) were divided into three groups: Group A; simple laparotomy group (sham). Group B; CBDL, Group C; CBDL rats treated with cilostazol (9mg/kg daily for 21 days). Six rats from each group were killed by the end of weeks one and three after surgery, livers and serum were collected for biochemical and histopathological studies. Aspartate aminotransferase, alanine aminotransferase, gama glutamyl transferase, alkaline phosphatase and total bilirubin serum levels decreased in the cilostazol treated rats, when compared with CBDL rats. The hepatic levels of tumor necrosis factor-alpha, transforming growth factor-beta, and platelet derived growth factor-B were significantly lower in cilostazol treated rats than that in CBDL rats. Cilostazol decreased vascular endothelial growth factor level and hemoglobin content in the livers. Cilostazol significantly lowered portal pressure, inhibited ductular proliferation, portal inflammation, hepatic fibrosis and decreased hepatic hydroxyproline contents. Administration of cilostazol in CBDL rats improved hepatic functions, decreased ductular proliferation, ameliorated portal inflammation, lowered portal hypertension and reduced fibrosis. These effects of cilostazol may be useful in the attenuation of liver injury in cholestasis.

  13. Local proliferation and extrahepatic recruitment of liver macrophages (Kupffer cells) in partial-body irradiated rats

    SciTech Connect

    Bouwens, L.; Knook, D.L.; Wisse, E.

    1986-06-01

    The relative significance of local proliferation and extrahepatic recruitment of Kupffer cells was investigated by partial-body irradiation before the induction of macrophage hyperplasia by zymosan. There was no difference in growth of the Kupffer cells population between nonirradiated rats and rats irradiated with the liver shielded, whereas irradiation of the liver with the rest of the body (bone marrow) shielded resulted in strong inhibition of growth (-61%). Splenectomy combined with bone marrow irradiation inhibited growth to a lesser extent as compared to liver irradiation (-38%). Monocyte and other leukocyte numbers were strongly reduced in peripheral blood and their accumulation in the liver was completely prevented by bone marrow irradiation. Our results demonstrate that local proliferation of resident Kupffer cells represents the predominant source for their increased number during hyperplasia.

  14. Hepatoprotective effect of green tea (Camellia sinensis) extract against tamoxifen-induced liver injury in rats.

    PubMed

    El-Beshbishy, Hesham A

    2005-09-30

    Tamoxifen citrate (TAM), is widely used for treatment of breast cancer. It showed a degree of hepatic carcinogenesis. The purpose of this study was to elucidate the antioxidant capacity of green tea (Camellia sinensis) extract (GTE) against TAM-induced liver injury. A model of liver injury in female rats was done by intraperitoneal injection of TAM in a dose of 45mg Kg(-1) day(-1), i.p. for 7 successive days. GTE in the concentration of 1.5 %, was orally administered 4 days prior and 14 days after TAM-intoxication as a sole source of drinking water. The antioxidant flavonoid; epicatechin (a component of green tea) was not detectable in liver and blood of rats in either normal control or TAM-intoxicated group, however, TAM intoxication resulted in a significant decrease of its level in liver homogenate of tamoxifenintoxicated rats. The model of TAM-intoxication elicited significant declines in the antioxidant enzymes (glutathione-S-transferase,glutathione peroxidase, superoxide dismutase and catalase) and reduced glutathione concomitant with significant elevations in TBARS (thiobarbituric acid reactive substance) and liver transaminases; sGPT (serum glutamate pyruvate transaminase) and sGOT (serum glutamate oxaloacetate transaminase) levels. The oral administration of 1.5 % GTE to TAM-intoxicated rats, produced significant increments in the antioxidant enzymes and reduced glutathione concomitant with significant decrements in TBARS and liver transaminases levels. The data obtained from this study speculated that 1.5 % GTE has the capacity to scavenge free radical and can protect against oxidative stress induced by TAM intoxication. Supplementation of GTE could be useful in alleviating tamoxifen-induced liver injury in rats.

  15. Endoplasmic reticulum stress involved in heart and liver injury in iron-loaded rats.

    PubMed

    Lou, Li-Xia; Geng, Bin; Chen, Yu; Yu, Fang; Zhao, Jing; Tang, Chao-Shu

    2009-07-01

    1. Iron overload contributes to the pathogenesis of various diseases and directly induces tissue injury. In the present study, we investigated the relationship between heart and liver injury induced by iron overload and cellular endoplasmic reticulum (ER) stress to explore the molecular mechanism of iron overload-induced cellular injury. 2. Iron overload in rats was generated by intraperitoneal injection of iron-dextran chronically (30 mg/kg per day for 9 weeks) or acutely (300 mg/kg once). Tissue injury was assessed by determining serum lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity, as well as malondialdehyde (MDA) content in the heart and liver. The ER stress response was analysed by expression of glucose-response protein 78 (GRP78) and activation of caspase 12. 3. In chronic iron-loaded rats, iron levels in the heart and liver were higher, by approximately 2- and 7.8-fold, respectively (P < 0.01), compared with control. Serum LDH, ALT and AST activity, as well as MDA content, GRP78 expression and caspase 12 activity in the heart and liver, were upregulated in chronically iron-loaded rats. In acute iron-loaded rats, iron content in the heart and liver was 51% and 63% higher than in controls (both P < 0.01). Serum LDH, ALT and AST activity, MDA content in the heart and liver and levels of ER stress markers were all increased in acute iron-loaded rats. N-Acetylcysteine (150 mg/kg, s.c.) lowered the levels of these parameters in acute iron-loaded rats. 4. The results of the present study indicate that ER stress may play an important role in iron-induced tissue injury and that reactive oxygen species may mediate the ER stress response in the pathogenesis of iron-overload cellular injury. PMID:19594550

  16. [Interaction of butylphthalide with rat and human liver CYP450 isoenzymes].

    PubMed

    Zhao, Qian; Hu, Jin-ping; Jiang, Ji; Li, Yan; Hu, Pei

    2015-05-01

    The work aims to study the drug metabolizing enzymes involved in the metabolism of butylphthalide and evaluate the induction and inhibition activities of butylphthalide on CYP450 isoenzymes by using in vitro (liver microsome incubation system of rats and human) and in vivo (CYP induced model of rats) method. Butylphthalide was incubated with selective inhibitors of CYP450, and its metabolic rate was determined to identify the metabolizing isoenzymes of NBP in rat (normal and induced rats) and human liver microsomes. The in vitro inhibition effect of butylphthalide on 6 main liver microsomal CYP450 isoenzymes was evaluated by using probe drugs; the induction and inhibition activities in vivo of butylphthalide on CYP450 isoenzymes were evaluated by NBP ig dosing (160 mg x kg(-1)) and iv dosing (20 mg x kg(-1)) in rats. After adding the specific inhibitors of CYP2C11, 2E1 and 3A 1/2 for rat, CYP2C19, 2E1 and 3A4/5 for human, the metabolism of NBP in rat and human liver microsomes were reduced 38.8%, 86.2%, 78.4% and 51.0%, 92.0%, 58.9% of control, respectively. The metabolic rates of NBP in CYP2E1 and 3A 1/2 induced rat liver microsomes were increased 25.5% and 68.9%. High concentration of NBP (≥ 200 μmol x L(-1), in vitro) could inhibit the activities of CYP1A2, 2C6, 2C11 and 2D2 in rats, and high concentration of NBP ( ≥ 15 μmol x L(-1), in vitro) could inhibit the activity of CYP2C19 in human. All the results indicated that NBP should be mainly metabolized by CYP2E1, 2C11 and 3A 1/2 in rats and CYP2E1, 2C19 and 3A4/5 in human. High concentration of NBP could inhibit human CYP2C19 in vitro. No significant induction/inhibition effects of NBP were observed on rat liver CYP450 isoforms after ig 160 mg x kg(-1) NBP or iv 20 mg x kg(-1) NBP. PMID:26234133

  17. Lipidomic changes in rat liver after long-term exposure to ethanol

    SciTech Connect

    Fernando, Harshica; Bhopale, Kamlesh K.; Kondraganti, Shakuntala; Kaphalia, Bhupendra S.; Shakeel Ansari, G.A.

    2011-09-01

    Alcoholic liver disease (ALD) is a serious health problem with significant morbidity and mortality. In this study we examined the progression of ALD along with lipidomic changes in rats fed ethanol for 2 and 3 months to understand the mechanism, and identify possible biomarkers. Male Fischer 344 rats were fed 5% ethanol or caloric equivalent of maltose-dextrin in a Lieber-DeCarli diet. Animals were killed at the end of 2 and 3 months and plasma and livers were collected. Portions of the liver were fixed for histological and immunohistological studies. Plasma and the liver lipids were extracted and analyzed by nuclear magnetic resonance (NMR) spectroscopy. A time dependent fatty infiltration was observed in the livers of ethanol-fed rats. Mild inflammation and oxidative stress were observed in some ethanol-fed rats at 3 months. The multivariate and principal component analysis of proton and phosphorus NMR spectroscopy data of extracted lipids from the plasma and livers showed segregation of ethanol-fed groups from the pair-fed controls. Significant hepatic lipids that were increased by ethanol exposure included fatty acids and triglycerides, whereas phosphatidylcholine (PC) decreased. However, both free fatty acids and PC decreased in the plasma. In liver lipids unsaturation of fatty acyl chains increased, contrary to plasma, where it decreased. Our studies confirm that over-accumulation of lipids in ethanol-induced liver steatosis accompanied by mild inflammation on long duration of ethanol exposure. Identified metabolic profile using NMR lipidomics could be further explored to establish biomarker signatures representing the etiopathogenesis, progression and/or severity of ALD. - Highlights: > Long term exposure to ethanol was studied. > A nuclear magnetic resonance (NMR) spectroscopy based lipidomic approach was used. > We examined the clustering pattern of the NMR data with principal component analysis. > NMR data were compared with histology and

  18. Hepatoprotective activity of Haridradi ghrita on carbon tetrachloride-induced liver damage in rats.

    PubMed

    Satturwar, P M; Fulzele, S V; Joshi, S B; Dorle, A K

    2003-12-01

    Haridradi ghrita, a ghee based polyherbal formulation, (50, 100, 200 and 300 mg/kg) significantly lowered marker enzymes (SGPT, SGOT, ALP) and bilirubin in serum and liver peroxide, superoxide dismutase and catalase in liver homogenate following CCl4 (0.7 ml/kg, ip) toxicity. The protective effect was further supported by reversal of CCl4 induced histological changes. The results demonstrate significant hepatoprotective action of H. ghrita in CCl4 damaged rats. PMID:15320500

  19. Extremely low-frequency magnetic field induces manganese accumulation in brain, kidney and liver of rats.

    PubMed

    Çelik, Mustafa Salih; Güven, Kemal; Akpolat, Veysi; Akdağ, Mehmet Zulkuf; Nazıroğlu, Mustafa; Gül-Güven, Reyhan; Çelik, M Yusuf; Erdoğan, Sait

    2015-06-01

    The aim of the present study was to determine the effects of extremely low-frequency magnetic field (ELF-MF) on accumulation of manganese (Mn) in the kidney, liver and brain of rats. A total of 40 rats were randomly divided into eight groups. Four control groups received 0, 3.75, 15 and 60 mg Mn per kg body weight orally every 2 days for 45 days, respectively. The remaining four groups received same concentrations of Mn and were also exposed to ELF-MF (1.5 mT; 50 Hz) for 4 h for 5 days a week during 45 days. Following the last exposure, kidney, liver and brain were taken from all rats and they were analyzed for Mn accumulation levels using an inductively coupled plasma-optical emission spectrometer. In result of the current study, we observed that Mn levels in brain, kidney and liver were higher in Mn groups than in control groups. Mn levels in brain, kidney and liver were also higher in Mn plus ELF-MF groups than in Mn groups. In conclusion, result of the current study showed that the ELF-MF induced manganese accumulation in kidney, liver and brain of rats.

  20. Characterization of CC-531 as a Rat Model of Colorectal Liver Metastases

    PubMed Central

    White, Sarah Beth; Procissi, Daniele; Chen, Jeane; Gogineni, Venkateswara Rao; Tyler, Patrick; Yang, Yihe; Omary, Reed A.; Larson, Andrew C.

    2016-01-01

    Purpose Surgical resection of colorectal liver metastases is not achievable in more than 70% of the cases. Although the liver directed therapies have become a part of the stand of care, lack of a preclinical model impedes the assessment of toxicity and therapeutic benefits attributed several candidate drugs or treatment regimens that can be designed. In the present study we aim develop and characterize a rat colorectal liver metastasis model. Materials and Methods Growth characteristics of CC-531 cells were determined in vitro followed by subcapsular liver implantation in syngeneic WAG/Rij rats. Tumor growth progression was followed over 3 weeks by ultrasound (US) and magnetic resonance imaging (MRI). Growth characteristics were also assessed by histopathology and immunohistochemistry in harvested tumor tissues. Results The doubling time of CC-531 cells was found be under 24hrs and all the implanted rats grew tumors. US imaging showed hypoechoic masses and MRI showed contrast enhancement representing complex tumor microenvironments. Hematoxylin and Eosin staining confirmed tumor growth and uniform CD31 staining in tumor confirmed even vessel density. Conclusion CC-531 can be used as a metastatic rat tumor colorectal liver metastases model with well-defined characteristics that can be readily followed by imaging whilst having a therapeutic window for interventions. PMID:27171151

  1. Purification of rat liver particulate neutral ribonuclease and comparison of properties with pancreas and serum ribonucleases.

    PubMed Central

    Bartholeyns, J; Baudhuin, P

    1977-01-01

    Rat liver particulate neutral ribonuclease (EC 3.1.4.22) was extensively purified (up to 40000-fold). It is shown to be an endonuclease, specific for pyrimidine bases, hydrolysing 5'-phosphate ester bonds. The enzyme specificity, Km, pH optimum, stability in acid medium and thermal stability at high temperature are the same as those of rat pancreatic and serum ribonucleases. Like pancreatic and serum neutral ribonucleases, the hepatic enzyme is sensitive to the liver natural inhibitor. This inhibitor was purified 8000-fold; its association with ribonuclease follows zero-order kinetics. These identical properties for ribonuclease of rat liver, pancreas and serum support the hypothesis [Bartholeyns, Peeters-Joris & Baudhuin (1975) Eur. J. Biochem. 60, 385-393] of an extrahepatic origin for the liver enzyme, the plasma ribonuclease of pancreatic origin being taken up by endocytosis in the liver. Neutral ribonuclease activity was detected in all rat organs investigated; its distribution among tissues is different from the distribution of the natural ribonuclear inhibitor. PMID:19011

  2. Antioxidative, antiapoptotic, and proliferative effect of curcumin on liver regeneration after partial hepatectomy in rats.

    PubMed

    Toydemir, Toygar; Kanter, Mehmet; Erboga, Mustafa; Oguz, Serhat; Erenoglu, Cengiz

    2015-02-01

    The aim of the present study was to assess the influence of curcumin on liver regeneration after partial hepatectomy (PH) in rats. A total of 24 male Sprague Dawley rats were divided into three groups: sham-operated (SH), PH, and PH + curcumin; each group contains eight animals. The rats in curcumin-treated groups were given curcumin (in a dose of 100 mg/kg body weight) once a day orally for 7 days, starting 3 days prior to hepatectomy operation. At 7 days after resection, liver samples were collected. The malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) levels were estimated in liver homogenates. Moreover, histopathological examination, mitotic index (MI), proliferating cell nuclear antigen labeling, proliferation index (PI), transferase-mediated 2'-deoxyuridine, 5'-triphosphate nick end-labeling assay, and apoptotic index (AI) were evaluated at 7 days after hepatectomy. As a result, curcumin significantly increased MI and PI and significantly decreased AI in PH rats. Additionally, curcumin remarkably inhibited MDA elevation, restored impaired antioxidant SOD activity and GSH level and also attenuated hepatic vacuolar degeneration and sinusoidal congestion. These results suggested that curcumin treatment had a beneficial effect on liver regenerative capacity of the remnant liver tissue after hepatectomy, probably due to its antioxidative, antiapoptotic, and proliferative properties.

  3. Respiration-driven proton translocation in rat liver mitochondria

    PubMed Central

    Mitchell, Peter; Moyle, Jennifer

    1967-01-01

    1. Pulses of acidity of the outer aqueous phase of rat liver mitochondrial suspensions induced by pulses of respiration are due to the translocation of H+ (or OH−) ions across the osmotic barrier (M phase) of the cristae membrane and cannot be attributed to the formation (with acid production) of a chemical intermediate that subsequently decomposes. 2. The effective quantity of protons translocated per bivalent reducing equivalent passing through the succinate-oxidizing and β-hydroxybutyrate-oxidizing spans of the respiratory chain are very close to 4 and 6 respectively. These quotients are constant between pH5·5 and 8·5 and are independent of changes in the ionic composition of the mitochondrial suspension medium provided that the conditions permit the accurate experimental measurement of the proton translocation. 3. Apparent changes in the →H+/O quotients may be induced by conditions preventing the occurrence of the usual backlash; these apparent changes of →H+/O are attributable to a very fast electrically driven component of the decay of the acid pulses that is not included in the experimental extrapolations. 4. Apparent changes in the →H+/O quotients may also be induced by the presence of anions, such as succinate, malonate and phosphate, or by cations such as Na+. These apparent changes of →H+/O are due to an increase in the rate of the pH-driven decay of the acid pulses. 5. The uncoupling agents, 2,4-dinitrophenol, carbonyl cyanide p-trifluoromethoxyphenylhydrazone and gramicidin increase the effective proton conductance of the M phase and thus increase the rate of decay of the respiration-driven acid pulses, but do not change the initial →H+/O quotients. The increase in effective proton conductance of the M phase caused by these uncouplers accounts quantitatively for their uncoupling action; and the fact that the initial →H+/O quotients are unchanged shows that uncoupler-sensitive chemical intermediates do not exist between the respiratory

  4. [Effect of Fuzheng Huayu recipe on CYP450 isozymes in normal and liver fibrosis rats].

    PubMed

    Zheng, Tian-hui; Liu, Wei; Li, Shu-ping; Yang, Tao; Wang, Chang-hong; Liu, Cheng-hai

    2015-03-01

    To study the effect of Fuzheng Huayu recipe (FZHY) on five types of isozymes of cytochrome P450 (CYP450) of normal and liver fibrosis rats by using the cocktail probe method. Dimethylnitrosamine ( DMN) was injected to induce the liver fibrosis model. After the tail vein injection with Cocktail probe solutions prepared with five CYP450s probe substrates (phenacetin-CYP1A2, omeprazole-CYP2C9, tolbutamide-CYP2C19, dextromethorphan-CYP2D6, midazolam-CYP3A4), the plasma concentrations of the five probe substrates were determined by LC-MS/MS, and the pharmacokinetic parameters were calculated by PK solutions 2. After the oral administration with FZHY, normal rats given phenacetin, omeprazole, tolbutamide and dextromethorphan showed increase in AUC(0-t) and decrease in CL to varying degrees, indicating that FZHY obviously inhibited the activities of CYP1A2, CYP2C9, CYP2C19 and CYP2D6 in normal rats, but with no obvious effect on the activity of CYP3A4. After the oral administration with FZHY, liver fibrosis rats treated with CYP2C9 showed the significant increase in AUC(0-t) and significant decrease in Vd, hut with no obvious changes in the pharmacokinetic parameters of other four types of prove substances, suggesting that FZHY could significantly inhibit the activity of CYP2C9 in rats but had no effect on the activities of CYP1A2, CYP2C19, CYP2D6 and CYP3A4. The changes in the activity of CYP450 isozymes in liver fibrosis rats may be the reason for FZHY's different effects on CYP450 isozymes in normal and liver fibrosis rats. PMID:26226765

  5. Influence of diets with different levels of protein and energy on liver albumin content in the rat.

    PubMed

    Maurice, M; Lardeux, B; De Saint-Steban, C; Bourdel, G; Feldmann, G

    1986-11-01

    The influence of protein ingestion on liver albumin synthesis and albumin content was investigated in rats fed protein as a meal (90% casein) given apart from the other dietary components provided ad libitum. In this condition, protein ingestion rapidly stimulates liver total protein synthesis. Separately fed rats were studied 6 and 20 h after the protein meal. Control rats fed mixed diets containing 13 or 80% casein were killed either during the absorptive (night) or postabsorptive (light) periods. The ratio of hepatic albumin synthesis to total protein synthesis remained fairly constant (12-15%) in all groups, indicating that albumin synthesis paralleled total protein synthesis. Liver albumin content measured in microsomes by immunonephelometry was significantly higher in separately fed rats killed 6 h postmeal than in those killed after 20 h. In rats fed 13% casein, the liver albumin content remained high regardless of the time of killing. In rats fed 80% casein, the albumin content was higher during the absorptive period than during the postabsorptive period. Immunoperoxidase staining of the hepatocyte organelles involved in albumin synthesis, especially the Golgi apparatus, was more intense for separately fed rats killed 6 h postmeal than for those killed after 20 h. Livers of rats fed 13% casein also exhibited a pattern indicative of high hepatocyte albumin content, whereas livers of rats fed 80% casein contained less. These results show that, in separate feeding, wide circadian variations of albumin synthesis run parallel to changes in liver albumin content.

  6. High-frequency ultrasound imaging to evaluate liver fibrosis progression in rats and yi guan jian herbal therapeutic effects.

    PubMed

    Chen, Wei; Chen, Jiun-Yu; Tung, Yu-Tang; Chen, Hsiao-Ling; Kuo, Chia-Wen; Chuang, Chia-Hui; Chong, Kowit-Yu; Mao, Frank Chiahung; Chen, Chuan-Mu

    2013-01-01

    The animals used in liver fibrosis studies must usually be sacrificed. Ultrasound has been demonstrated to have the ability to diagnose hepatic fibrosis and cirrhosis in experimental small-animal models. However, few studies have used high-frequency ultrasound (HFU, 40 MHz) to monitor changes in the rat liver and other hollow organs longitudinally. In this study, liver fibrosis was induced by administering dimethylnitrosamine (DMN) in SD rats, aged 8 weeks, for three consecutive days per week for up to 4 weeks. A Chinese herbal medicine Yi Guan Jian (YGJ) was orally administered (1.8 g/kg daily) to DMN-induced liver fibrosis rats for 2 weeks. Compared with the normal control rats, rats treated with DMN for either 2 weeks or 4 weeks had significantly lower body weights, liver indexes and elevation of hydroxyproline, GOT, and GPT contents. YGJ herbal treatment remarkably prevented rats from DMN-induced liver fibrosis. The HFU scoring results among the normal controls, 2-week DMN-treated rats, 4-week DMN-treated rats, and combined 2-week YGJ therapy with 4-week DMN-treated rats also reached statistical significance. Thus, HFU is an accurate tool for the longitudinal analysis of liver fibrosis progression in small-animal models, and the YGJ may be useful in reversing the development of hepatic fibrosis. PMID:24250714

  7. Effect of low temperature on metabolism of rat liver slices and epididymal fat pads.

    NASA Technical Reports Server (NTRS)

    Hillyard, L. A.; Entenman, C.

    1973-01-01

    Study of low temperature effects on the metabolism of radioisotope-tagged glucose and palmitate in rat liver slices and epididymal fat pads. The obtained data suggest that the oxidative capacity of rat liver and adipose tissue is maintained at low temperatures to a greater degree than the synthetic capacity. It was concluded that sufficient energy can be produced at 17 C for maintenance of essential tissue functions by these two tissues but that the energy requirements may not be met at 7 C.

  8. Kinetics and control of oxidative phosphorylation in rat liver mitochondria after dexamethasone treatment

    PubMed Central

    2004-01-01

    The present investigation was undertaken in order to evaluate the contributions of ATP synthesis and proton leak reactions to the rate of active respiration of liver mitochondria, which is altered following dexamethasone treatment (1.5 mg/kg per day for 5 days). We applied top-down metabolic control analysis and its extension, elasticity analysis, to gain insight into the mechanisms of glucocorticoid regulation of mitochondrial bioenergetics. Liver mitochondria were isolated from dexamethasone-treated, pair-fed and control rats when in a fed or overnight fasted state. Injection of dexamethasone for 5 days resulted in an increase in the fraction of the proton cycle of phosphorylating liver mitochondria, which was associated with a decrease in the efficiency of the mitochondrial oxidative phosphorylation process in liver. This increase in proton leak activity occurred with little change in the mitochondrial membrane potential, despite a significant decrease in the rate of oxidative phosphorylation. Regulation analysis indicates that mitochondrial membrane potential homoeostasis is achieved by equal inhibition of the mitochondrial substrate oxidation and phosphorylation reactions in rats given dexamethasone. Our results also suggest that active liver mitochondria from dexamethasone-treated rats are capable of maintaining phosphorylation flux for cellular purposes, despite an increase in the energetic cost of mitochondrial ATP production due to increased basal proton permeability of the inner membrane. They also provide a complete description of the effects of dexamethasone treatment on liver mitochondrial bioenergetics. PMID:15175015

  9. Metabonomic evaluation of idiosyncrasy-like liver injury in rats cotreated with ranitidine and lipopolysaccharide

    SciTech Connect

    Maddox, Jane F. . E-mail: maddox@msu.edu; Luyendyk, James P.; Cosma, Gregory N.; Breau, Alan P.; Bible, Roy H.; Harrigan, George G.; Goodacre, Royston; Ganey, Patricia E.; Cantor, Glenn H.; Cockerell, Gary L.; Roth, Robert A. . E-mail: rothr@msu.edu

    2006-04-01

    Idiosyncratic liver injury occurs in a small fraction of people on certain drug regimens. The cause of idiosyncratic hepatotoxicity is not known; however, it has been proposed that environmental factors such as concurrent inflammation initiated by bacterial lipopolysaccharide (LPS) increase an individual's susceptibility to drug toxicity. Ranitidine (RAN), a histamine-2 receptor antagonist, causes idiosyncratic liver injury in humans. In a previous report, idiosyncrasy-like liver toxicity was created in rats by cotreating them with LPS and RAN. In the present study, the ability of metabonomic techniques to distinguish animals cotreated with LPS and RAN from those treated with each agent individually was investigated. Rats were treated with LPS or its vehicle and with RAN or its vehicle, and urine was collected for nuclear magnetic resonance (NMR)- and mass spectroscopy-based metabonomic analyses. Blood and liver samples were also collected to compare metabonomic results with clinical chemistry and histopathology. NMR metabonomic analysis indicated changes in the pattern of metabolites consistent with liver damage that occurred only in the LPS/RAN cotreated group. Principal component analysis of urine spectra by either NMR or mass spectroscopy produced a clear separation of the rats treated with LPS/RAN from the other three groups. Clinical chemistry (serum alanine aminotransferase and aspartate aminotransferase activities) and histopathology corroborated these results. These findings support the potential use of a noninvasive metabonomic approach to identify drug candidates with potential to cause idiosyncratic liver toxicity with inflammagen coexposure.

  10. Bees' Honey Protects the Liver of Male Rats against Melamine Toxicity

    PubMed Central

    El Rabey, Haddad A.; Al-Seeni, Madeha N.; Al-Solamy, Suad M.

    2013-01-01

    The protective effect of natural bees' honey to the liver of male albino rats against melamine toxicity was studied. Melamine supplementation at a dose of 20000 ppm in the diet for 28 days induced adverse effects on the liver, decreased serum total protein and increased liver enzyme: alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. Histological changes of the melamine supplemented group showed necrosis in the hepatic tissues around the central veins of the liver and precipitation of melamine crystals. Treating the male albino rats (that were presupplemented regularly with 20000 ppm melamine) with natural bees' honey at a dose of 2.5 g/kg body weight for 28 days improved both liver functions and increased serum protein. In addition, a positive impact on the shape of the cells after treatment with honey compared to the positive melamine supplemented group was observed. In conclusion, the results of this study revealed that the use of natural bees' honey has the ability to protect the liver of rats against the toxic effects of melamine. PMID:23971045

  11. Peroxisome proliferator-activated receptor-alpha expression in rat liver during postnatal development.

    PubMed

    Panadero, M; Herrera, E; Bocos, C

    2000-08-01

    The expression of the peroxisome proliferator-activated receptor-alpha (PPARalpha) as well as of some related genes was studied in rat liver at different stages of development (from 19-day-old fetuses to 1 month-old rats). The level of PPARalpha mRNA appeared higher in neonates than in fetuses or 1 month-old rats. Whereas the pattern for phosphoenolpyruvate carboxykinase (PEPCK) mRNA level was similar to that of PPARalpha, the mRNA level of both acyl-CoA oxidase (ACO) and apolipoprotein CIII (apo CIII) showed diverse profiles. Western blotting analysis also revealed an increased level of PPARalpha protein in liver of suckling rats. Similarities of mRNA PEPCK and PPARalpha expression indicate a common control mechanism, where both nutritional and hormonal factors may be involved. PMID:11018288

  12. Estrogen- and progestin-receptor complexes and their interaction with rat liver cell nuclei during ontogenesis

    SciTech Connect

    Konoplya, E.F.; Luksha, G.L.; Savateev, S.K.; Naumov, A.D.

    1986-11-10

    Steroid-receptor complexes (SRC) of estrogens and progestins have been isolated from the rat liver and purified 1500-2000-fold. Both in the state of the initial cytosol and purified 2000-fold, the SRC were characterized by gel filtration on Sephadex G-100 and by DEAE-cellulose chromatography. The purified SRC from the rat liver were used for binding to isolated liver cell nuclei from rats of different ages (1.5 months, 6 months, 12 months, 24 months). The maximum binding of SRC of progestins and estrogens from the rat liver is observed with homologous nuclei of 1.5-month-old rats. With age the binding of SRC by the nuclei decreases progressively and reaches a minimum by 24 months. The detected differences in the binding of SRC by the nuclei of cells of animals of different ages, in their opinion, may lie at the basis of changes in the functioning of the organism under the influence of hormones at different stages of ontogenesis.

  13. Glutamic oxaloacetic transaminase isozymes from rat liver. Purification and physicochemical characterization.

    PubMed

    Huynh, Q K; Sakakibara, R; Watanabe, T; Wada, H

    1980-07-01

    Glutamic oxaloacetic transaminase isozymes were purified simultaneously to homogeneity from rat liver with high yields. Three subforms of mitochondrial isozyme and three subforms of cytosolic isozyme were separated by chromatography on CM-Sephadex and electrophoresis on polyacrylamide gel. The general enzymatic properties of the purified isozymes such as their kinetic parameters, isoelectric points, molecular weights, amino acid compositions, NH2-terminal amino acid sequences and COOH-terminal amino acids were determined. Most of these properties of the isozymes are similar to those of the corresponding isozymes from other sources, such as rat brain and pig and human heart. In amino acid compositions, cytosolic isozyme from rat liver has more proline and glycine and less arginine, threonine and leucine than pig heart cytosolic isozyme; the mitochondrial isozyme has more glutamic acid and glycine and less serine than the corresponding pig heart isozyme. The NH2-terminal amino acid sequences of GOT isozymes from rat liver were identical with those of the GOT isozymes from pig heart up to the 10th residues except for the 5th residues. The subforms of mitochondrial isozyme from rat liver were generated on storage at 4 degrees C for 4-8 weeks.

  14. Serine dehydratase expression decreases in rat livers injured by chronic thioacetamide ingestion.

    PubMed

    López-Flores, Inmaculada; Barroso, Juan B; Valderrama, Raquel; Esteban, Francisco J; Martínez-Lara, Esther; Luque, Francisco; Peinado, M Angeles; Ogawa, Hirofumi; Lupiáñez, José A; Peragón, Juan

    2005-01-01

    Serine dehydratase (SerDH) is a gluconeogenic enzyme involved in the catabolism of serine, which is regulated by the composition of their diet and their hormonal status in rats. This study examines how chronic injury caused to the liver of rats by the ingestion of thioacetamide (TAA) affects SerDH protein, mRNA levels, enzyme kinetics and its tissue location. After 97 days' oral intake of TAA, the activity of SerDH at all substrate concentrations assayed was about 60% lower than in controls. No significant differences in Km values were found between the treated group and controls. Immunoblotting and immunohistochemistry revealed a significant reduction in the level of SerDH protein in the livers of the treated rats. SerDH was detected specifically in the periportal zone of the hepatic acinus and this location did not change in response to TAA treatment. The level of SerDH mRNA, quantified by reverse transcription and polymerase chain reaction, was significantly lower in treated rats than in the controls. The present findings suggest that the SerDH expression is rendered to be down regulatory during chronic liver injury induced by TAA. These results enhance our understanding about the biochemical mechanisms implied in the control and integration of serine catabolism during liver injury in rat.

  15. PASS-Predicted Hepatoprotective Activity of Caesalpinia sappan in Thioacetamide-Induced Liver Fibrosis in Rats

    PubMed Central

    Kadir, Farkaad A.; Kassim, Normadiah M.; Abdulla, Mahmood Ameen; Ahmadipour, Fatemeh; Yehye, Wageeh A.

    2014-01-01

    The antifibrotic effects of traditional medicinal herb Caesalpinia sappan (CS) extract on liver fibrosis induced by thioacetamide (TAA) and the expression of transforming growth factor β1 (TGF-β1), α-smooth muscle actin (αSMA), and proliferating cell nuclear antigen (PCNA) in rats were studied. A computer-aided prediction of antioxidant and hepatoprotective activities was primarily performed with the Prediction Activity Spectra of the Substance (PASS) Program. Liver fibrosis was induced in male Sprague Dawley rats by TAA administration (0.03% w/v) in drinking water for a period of 12 weeks. Rats were divided into seven groups: control, TAA, Silymarin (SY), and CS 300 mg/kg body weight and 100 mg/kg groups. The effect of CS on liver fibrogenesis was determined by Masson's trichrome staining, immunohistochemical analysis, and western blotting. In vivo determination of hepatic antioxidant activities, cytochrome P450 2E1 (CYP2E1), and matrix metalloproteinases (MPPS) was employed. CS treatment had significantly increased hepatic antioxidant enzymes activity in the TAA-treated rats. Liver fibrosis was greatly alleviated in rats when treated with CS extract. CS treatment was noted to normalize the expression of TGF-β1, αSMA, PCNA, MMPs, and TIMP1 proteins. PASS-predicted plant activity could efficiently guide in selecting a promising pharmaceutical lead with high accuracy and required antioxidant and hepatoprotective properties. PMID:24701154

  16. LOCALIZATION OF POLYSOME-BOUND ALBUMIN AND SERINE DEHYDRATASE IN RAT LIVER CELL FRACTIONS

    PubMed Central

    Ikehara, Yukio; Pitot, Henry C.

    1973-01-01

    The polysomes involved in albumin and serine dehydratase synthesis were identified and localized by the binding to rat liver polysomes of anti-rat serum albumin and anti-serine dehydratase [125I]Fab dimer and monomer. Techniques were developed for the isolation of undegraded free and membrane-bound polysomes and for the preparation of [125I]Fab monomers and dimers from the IgG obtained from the antisera to the two proteins, rat serum albumin and serine dehydratase. The distribution of anti-rat serum albumin [125I]Fab dimer in the polysome profile is in accordance with the size of polysomes that are expected to be synthesizing albumin. By direct precipitation, it has been demonstrated that nascent chains isolated from the membrane-bound polysomes by puromycin were precipitated by anti-rat serum albumin-IgG at a level of 5–6 times those released from free polysomes. Anti-rat serum albumin-[125I]Fab dimer reacted with membrane-bound polysomes almost exclusively compared to the binding of nonimmune, control [125I]Fab dimer; a significant degree of binding of anti-rat serum albumin-[125I]Fab to free polysomes was also obtained. The [125I]Fab dimer made from normal control rabbit serum does not react with polysomes from liver at all and this preparation will not interact with polysomes extracted from tissues that do not synthesize rat serum albumin. Both anti-serine dehydratase-[125I]Fab monomer and dimer react with free and bound polysomes from livers of animals fed a chow diet or those fed a high 90% protein diet and given glucagon. In the latter instance, however, it is clear that the majority of the binding occurs to the bound polysomes. Furthermore, the specificity of this reaction may be further shown by the use of kidney polysomes that do not normally synthesize serine dehydratase. When these latter polysomes are isolated, even after the addition of crude and purified serine dehydratase, no reaction with anti-serine dehydratase-Fab fragments could be

  17. Ring-Oxidative Biotransformation and Drug Interactions of Propofol in the Livers of Rats

    PubMed Central

    Tai, Yu-Ting; Lin, Yi-Ling; Chang, Chia-Chen; Cherng, Yih-Giun; Don, Ming-Jaw; Chen, Ruei-Ming

    2015-01-01

    Propofol, an intravenous anesthetic agent, is widely used for inducing and maintaining anesthesia during surgical procedures and for sedating intensive care unit patients. In the clinic, rapid elimination is one of the major advantages of propofol. Meanwhile, the biotransformation and drug interactions of propofol in rat livers are still little known. In this study, we evaluated the ring-oxidative metabolism of propofol in phenobarbital-treated rat livers and possible drug interactions. Administration of phenobarbital to male Wistar rats significantly increased levels of hepatic cytochrome P450 (CYP) 2B1/2 and microsomal pentoxyresorufin O-dealkylase (PROD) activity. Analyses by high-performance liquid chromatography and liquid chromatography mass spectroscopy revealed that propofol was metabolized by phenobarbital-treated rat liver microsomes into 4-hydroxypropofol. In comparison, PROD activity and 4-hydroxy-propofol production from propofol metabolism were suppressed by orphenodrine, an inhibitor of CYP2B1/2, and a polyclonal antibody against rat CYP2B1/2 protein. Furthermore, exposure of rats to propofol did not affect the basal or phenobarbital-enhanced levels of hepatic CYP2B1/2 protein. Meanwhile, propofol decreased the dealkylation of pentoxyresorufin by phenobarbital-treated rat liver microsomes in a concentration-dependent manner. Taken together, this study shows that rat hepatic CYP2B1/2 plays a critical role in the ring-oxidative metabolism of propofol into 4-hydroxypropofol, and this anesthetic agent can inhibit CYP2B1/2 activity without affecting protein synthesis. PMID:25710017

  18. Caffeic acid attenuates rat liver reperfusion injury through sirtuin 3-dependent regulation of mitochondrial respiratory chain.

    PubMed

    Mu, Hong-Na; Li, Quan; Pan, Chun-Shui; Liu, Yu-Ying; Yan, Li; Hu, Bai-He; Sun, Kai; Chang, Xin; Zhao, Xin-Rong; Fan, Jing-Yu; Han, Jing-Yan

    2015-08-01

    Sirtuin 3 (Sirt3) plays critical roles in regulating mitochondrial oxidative metabolism. However, whether Sirt3 is involved in liver ischemia and reperfusion (I/R) injury remains elusive. Caffeic acid (CA) is a natural antioxidant derived from Salvia miltiorrhiza. Whether CA protects against liver I/R injury through regulating Sirt3 and the mitochondrial respiratory chain (MRC) is unclear. This study investigated the effect of CA on liver I/R injury, microcirculatory disturbance, and potential mechanisms, particularly focusing on Sirt3-dependent MRC. Liver I/R of male Sprague-Dawley rats was established by occlusion of portal area vessels for 30 min followed by 120 min of reperfusion. CA (15 mg/kg/h) was continuously infused via the femoral vein starting 30 min before ischemia. After I/R, Sirt3 expression, and MRC activity decreased, acetylation of NADH dehydrogenase [ubiquinone] 1 alpha subcomplex subunit 9 and succinate dehydrogenase complex, subunit A, flavoprotein variant provoked, and the liver microcirculatory disturbance and injury were observed. Treatment with CA attenuated liver injury, inhibited Sirt3 down-expression, and up-regulated MRC activity. CA attenuated rat liver microcirculatory disturbance and oxidative injury through regulation of Sirt3 and the mitochondrial respiratory chain. PMID:25960048

  19. Saturated hydrogen saline attenuates endotoxin-induced acute liver dysfunction in rats.

    PubMed

    Xu, X-F; Zhang, J

    2013-01-01

    To determine the effect of saturated hydrogen saline on lipopolysaccharide (LPS)-induced acute liver dysfunction, rats were divided into control, LPS, and LPS plus saturated hydrogen saline (LPS+H(2)) groups. Treatment with saturated hydrogen saline prolonged the median survival time and reduced liver dysfunction. Moreover, saturated hydrogen saline significantly reduced pathological alterations in liver tissues, the number of ballooned hepatocytes, serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 levels, and myeloperoxidase (MPO) and malondialdehyde (MDA) levels in liver tissues (P<0.05). Cell apoptosis was detected in liver tissues after LPS treatment, and attenuated by saturated hydrogen saline treatment. Saturated hydrogen saline also decreased phosphorylated extracellular signal-regulated kinase (p-ERK), phosphorylated Jun kinase (p-JNK), nuclear factor-kappa B (NF-kappaB), and second mitochondria-derived activator of caspase (Smac) levels, and increased p38 activation (P<0.05). Thus, saturated hydrogen saline may attenuate LPS-induced acute liver dysfunction in rats, possibly by reducing inflammation and cell apoptosis. Mitogen-activated protein kinase (MAPK), NF-kappaB, and Smac may contribute to saturated hydrogen saline-mediated liver protection.

  20. Simple steatosis sensitizes cholestatic rats to liver injury and dysregulates bile salt synthesis and transport

    PubMed Central

    Lionarons, Daniël A.; Heger, Michal; van Golen, Rowan F.; Alles, Lindy K.; van der Mark, Vincent A.; Kloek, Jaap J.; de Waart, Dirk R.; Marsman, Hendrik A.; Rusch, Henny; Verheij, Joanne; Beuers, Ulrich; Paulusma, Coen C.; van Gulik, Thomas M.

    2016-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder. It is uncertain if simple steatosis, the initial and prevailing form of NAFLD, sensitizes the liver to cholestasis. Here, we compared the effects of obstructive cholestasis in rats with a normal liver versus rats with simple steatosis induced by a methionine/choline-deficient diet. We found that plasma liver enzymes were higher and hepatic neutrophil influx, inflammation, and fibrosis were more pronounced in animals with combined steatosis and cholestasis compared to cholestasis alone. Circulating bile salt levels were markedly increased and hepatic bile salt composition shifted from hydrophilic tauro-β-muricholate to hydrophobic taurocholate. This shift was cytotoxic for HepG2 hepatoma cells. Gene expression analysis revealed induction of the rate-limiting enzyme in bile salt synthesis, cytochrome P450 7a1 (CYP7A1), and modulation of the hepatic bile salt transport system. In conclusion, simple steatosis sensitizes the liver to cholestatic injury, inflammation, and fibrosis in part due to a cytotoxic shift in bile salt composition. Plasma bile salt levels were elevated, linked to dysregulation of bile salt synthesis and enhanced trafficking of bile salts from the liver to the systemic circulation. PMID:27535001

  1. Food-anticipatory activity and liver per1-luc activity in diabetic transgenic rats

    NASA Technical Reports Server (NTRS)

    Davidson, Alec J.; Stokkan, Karl-Arne; Yamazaki, Shin; Menaker, Michael

    2002-01-01

    The mammalian Per1 gene is an important component of the core cellular clock mechanism responsible for circadian rhythms. The rodent liver and other tissues rhythmically express Per1 in vitro but typically damp out within a few cycles. In the liver, the peak of this rhythm occurs in the late subjective night in an ad lib-fed rat, but will show a large phase advance in response to restricted availability of food during the day. The relationship between this shift in the liver clock and food-anticipatory activity (FAA), the circadian behavior entrained by daily feeding, is currently unknown. Insulin is released during feeding in mammals and could serve as an entraining signal to the liver. To test the role of insulin in the shift in liver Per1 expression and the generation of FAA, per-luciferase transgenic rats were made diabetic with a single injection of streptozotocine. Following 1 week of restricted feeding and locomotor activity monitoring, liver was collected for per-luc recording. In two separate experiments, FAA emerged and liver Per1 phase-shifted in response to daytime 8-h food restriction. The results rule out insulin as a necessary component of this system.

  2. GH binding to liver in young and old female rats: relation to somatomedin-C secretion

    SciTech Connect

    Takahashi, S.; Meites, J.

    1987-11-01

    Age-related changes in binding of /sup 125/I-bovine GH to liver membrane fractions were measured in female Long-Evans rats 2, 6, 12, and 20 months of age. Specific GH binding did not change between 2 and 6 months of age but increased significantly at 12 and 20 months of age. Scatchard analyses showed that the plots were curvilinear and consisted of high- and low-affinity binding sites. The age-related increases in binding sites were mainly due to an increase in number of low-affinity binding sites. Serum somatomedim-C (SM-C) levels in 20-month-old rats were about half those in the 6-month-old rats. Twice daily injections of ovine GH (2 mg/kg body wt) for 7 days depressed liver GH binding and increased serum SM-C levels in 19-month-old female rats, but had no effect on GH binding in 2-month-old female rats. These results suggest that the increase in liver GH binding sites and the decrease in SM-C secretion are associated with our previously reported decrease in GH secretion in old female rats.

  3. Assessment of liver steatosis and fibrosis in rats using integrated coherent anti-Stokes Raman scattering and multiphoton imaging technique

    NASA Astrophysics Data System (ADS)

    Lin, Jian; Lu, Fake; Zheng, Wei; Xu, Shuoyu; Tai, Dean; Yu, Hanry; Huang, Zhiwei

    2011-11-01

    We report the implementation of a unique integrated coherent anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG), and two-photon excitation fluorescence (TPEF) microscopy imaging technique developed for label-free monitoring of the progression of liver steatosis and fibrosis generated in a bile duct ligation (BDL) rat model. Among the 21 adult rats used in this study, 18 rats were performed with BDL surgery and sacrificed each week from weeks 1 to 6 (n = 3 per week), respectively; whereas 3 rats as control were sacrificed at week 0. Colocalized imaging of the aggregated hepatic fats, collagen fibrils, and hepatocyte morphologies in liver tissue is realized by using the integrated CARS, SHG, and TPEF technique. The results show that there are significant accumulations of hepatic lipid droplets and collagen fibrils associated with severe hepatocyte necrosis in BDL rat liver as compared to a normal liver tissue. The volume of normal hepatocytes keeps decreasing and the fiber collagen content in BDL rat liver follows a growing trend until week 6; whereas the hepatic fat content reaches a maximum in week 4 and then appears to stop growing in week 6, indicating that liver steatosis and fibrosis induced in a BDL rat liver model may develop at different rates. This work demonstrates that the integrated CARS and multiphoton microscopy imaging technique has the potential to provide an effective means for early diagnosis and detection of liver steatosis and fibrosis without labeling.

  4. 31P-NMR SPECTROSCOPY OF RAT LIVER DURING SIMPLE STORAGE OR CONTINUOUS HYPOTHERMIC PERFUSION1

    PubMed Central

    Rossaro, Lorenzo; Murase, Noriko; Caldwell, Cary; Farghali, Hassan; Casavilla, Adrian; Starzl, Thomas E.; Ho, Chien; Van Thiel, David H.

    2010-01-01

    SUMMARY The ATP content and intracellular pH (pHi)3 of isolated rat liver before, during, and after cold preservation in either UW-lactobionate (UW, n=10) or Euro-Collins (EC, n=8) solutions were monitored using phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy. The 31P-NMR spectra were obtained on a 4.7-Tesla system operating at 81 MHz. Fructose metabolism, liver enzyme release, O2 consumption, and rat survival after liver transplantation were also evaluated. During simple cold storage (SCS), the ATP level declined to undetectable levels with both preservation solutions while the pHi declined to approximately 7.0. In contrast, during continuous hypothermic perfusion (CHP), hepatic ATP levels remained measurable during the 24-hour EC preservation and actually increased significantly (p>0.01) during UW preservation. After reperfusion at 37°C with Krebs-lactate, the SCS livers treated with EC differed significantly from the UW livers in terms of their ATP and pHi as well as their response to a fructose challenge. In contrast, livers undergoing CHP demonstrated similar behaviors with both solutions. These results demonstrate an increase in the hepatic ATP content during CHP which occurs with UW but is not seen with EC. On the other hand, only livers that were simply stored with UW achieved significant survival after transplant, while CHP livers were affected by vascular damage as demonstrated by fatal thrombosis after transplant. These data suggest that ATP content is not the only determinant of good liver function although a system of hypothermic perfusion might further improve liver preservation efficacy should injury to vascular endothelium be avoided. PMID:1402332

  5. Anti-inflammatory liposomes have no impact on liver regeneration in rats

    PubMed Central

    Jepsen, Betina Norman; Andersen, Kasper Jarlhelt; Knudsen, Anders Riegels; Nyengaard, Jens Randel; Hamilton-Dutoit, Stephen; Svendsen, Pia; Etzerodt, Anders; Møller, Holger Jon; Moestrup, Søren Kragh; Graversen, Jonas Heilskov; Mortensen, Frank Viborg

    2015-01-01

    Introduction Surgical resection is the gold standard in treatment of hepatic malignancies, giving the patient the best chance to be cured. The liver has a unique capacity to regenerate. However, an inflammatory response occurs during resection, in part mediated by Kupffer cells, that influences the speed of regeneration. The aim of this study was to investigate the effect of a Kupffer cell targeted anti-inflammatory treatment on liver regeneration in rats. Methods Two sets of animals, each including four groups of eight rats, were included. Paired groups from each set received treatment with placebo, low dose dexamethasone, high dose dexamethasone or low dose anti-CD163 dexamethasone. Subsequently, the rats underwent 70% partial hepatectomy. The two sets were evaluated on postoperative day 2 or 5, respectively. Blood was drawn for circulating markers of inflammation and liver cell damage; liver tissue was sampled for analysis of regeneration rate and proliferation index. Results The high dose dexamethasone group had significantly lower body and liver weight than the placebo and anti-CD163-dex groups. There were no differences in liver regeneration rates between groups. Hepatocyte proliferation was completed faster in the placebo group, although this was not significant. The anti-CD163-dex group showed increased blood levels of albumin and alanine aminotransferase and a diminished inflammatory response in terms of significantly reduced haptoglobin, α2-macroglobulin and Interleukine-6. Conclusion Low dose dexamethasone targeted to Kupffer cells does not affect histological liver cell regeneration after 70% hepatectomy in rats, but reduces the inflammatory response judged by circulating markers of inflammation. PMID:26779334

  6. Liver tumor promoting effect of etofenprox in rats and its possible mechanism of action.

    PubMed

    Hojo, Yuri; Shiraki, Ayako; Tsuchiya, Takuma; Shimamoto, Keisuke; Ishii, Yuji; Suzuki, Kazuhiko; Shibutani, Makoto; Mitsumori, Kunitoshi

    2012-01-01

    To investigate the liver tumor-promoting effects of etofenprox (ETF), a pyrethroid-like insecticide, 6 week-old male F344 rats were given an intraperitoneal injection of N-diethylnitrosamine (DEN). After 2 weeks from the DEN treatment, 12 rats per group received a powdered diet containing 0, 0.25, 0.50, or 1.0% ETF for 8 weeks. At the time of 2nd week of ETF administration, all animals were subjected to two-thirds partial hepatectomy (PH). One rat per group except for the 0.25% ETF group died due to surgical operation of PH. The number and area of glutathione S-transferase placental form (GST-P) positive foci significantly increased in the livers of DEN-initiated rats given 0.50% and 1.0% ETF compared with the DEN-alone group. Quantitative real-time RT-PCR analysis revealed that the mRNA expression of phase I enzymes Cyp2b1/2, phase II enzymes such as Akr7a3, Gsta5, Ugt1a6, Nqo1 significantly increased in the DEN+ETF groups. The immunohistochemistry showed the translocation of CAR from the cytoplasm to the nuclei of hepatocytes in the ETF-treated groups. Reactive oxygen species (ROS) production increased in microsomes isolated from the livers of ETF-treated rats, and thiobarbituric acid-reactive substances (TBARS) levels and 8- hydroxy-2-deoxyguanosine (8-OHdG) content significantly increased in all of the ETF-treated groups and DEN+1.0% ETF group, respectively. The results of the present study indicate that ETF has a liver tumor-promoting activity in rats, and suggest that ETF activates the constitutive active/androstane receptor (CAR) and enhances microsomal ROS production, resulting in the upregulation of Nrf2 gene batteries; such an oxidative stress subsequently induces liver tumor-promoting effects by increased cellular proliferation.

  7. Beneficial effects of enalapril on chlorhexidine digluconate-induced liver peritoneal fibrosis in rats.

    PubMed

    Lee, Chung-Jen; Subeq, Yi-Maun; Lee, Ru-Ping; Ke, Chen-Yen; Lin, Nien-Tsung; Hsu, Bang-Gee

    2011-08-31

    Peritoneal fibrosis (PF) is a recognized complication of long-term peritoneal dialysis (PD) and can lead to ultrafiltration failure. The present study was designed to investigate the protective effects of enalapril on chlorhexidine digluconate-induced liver PF by decreasing transforming growth factor-β1 (TGF-β1) production in rats. PF was induced in Sprague-Dawley rats by daily administration of 0.5 ml 0.1% chlorhexidine digluconate in normal saline via PD tube for one week. Rats received daily intravenous injections of low dose enalapril (1 mg/kg), or high dose enalapril (2.5 mg/kg), for one week. After 7 days, conventional 4.25% Dianeal (30 ml) was administered via a PD catheter with a dwell time of 4 h and assessment of peritoneal function. At the end of dialysis, the rats were sacrificed and liver peritoneum was harvested for microscopic examination and immunohistochemistry. There was no significant difference in mean arterial pressure and heart rate between groups. After 4 h of PD, the D₄/P₄(urea) level was reduced, the D₄/D₀ glucose level, serum and the dialysate TGF-β1 level was increased, the liver peritoneum was markedly thicker, and the expression of TGF-β1, alpha-smooth muscle actin (α-SMA), fibronectin, collagen and vascular endothelial growth factor (VEGF) were elevated in the PF group compared with the vehicle group. High dose of enalapril decreased the serum and dialysate TGF-β1 levels, decreased the thickness of the liver peritoneum, and decreased the expression of TGF-β1, α-SMA, fibronectin, collagen and VEGF-positive cells in the liver peritoneum. Low dose of enalapril did not protect against chlorhexidine digluconate-induced PF in the rat. Enalapril protected against chlorhexidine digluconate-induced PF in rats by decreasing TGF-β1 production. PMID:22129820

  8. Propiconazole-induced cytochrome P450 gene expression and enzymatic activities in rat and mouse liver.

    PubMed

    Sun, Guobin; Thai, Sheau-Fung; Tully, Douglas B; Lambert, Guy R; Goetz, Amber K; Wolf, Douglas C; Dix, David J; Nesnow, Stephen

    2005-02-15

    Propiconazole is a N-substituted triazole used as a fungicide on fruits, grains, seeds, hardwoods, and conifers. In the present study, propiconazole was examined for its effects on the expression of hepatic cytochrome P450 genes and on the activities of P450 enzymes in male Sprague-Dawley rats and male CD-1 mice. Rats and mice were administered propiconazole by gavage daily for 14 days at doses of 10, 75, and 150 mg/kg body weight/day. Quantitative real time RT-PCR assays of rat hepatic RNA samples from animals treated at the 150 mg/kg body weight/day dose revealed significant mRNA overexpression of the following genes compared to control: CYP1A2 (1.62-fold), CYP2B1 (10.8-fold), CYP3A1/CYP3A23 (2.78-fold), and CYP3A2 (1.84-fold). In mouse liver, propiconazole produced mRNA overexpression of Cyp2b10 (2.39-fold) and Cyp3a11 (5.19-fold). mRNA expression of CYP1A1 was not detected in liver tissues from treated or controls animals from either species. Propiconazole significantly induced both pentoxyresorufin O-dealkylation (PROD) and methoxyresorufin O-dealkylation (MROD) activities in both rat and mouse liver at the 150 mg/kg body weight/day and 75 mg/kg body weight/day doses. In summary, these results indicated that propiconazole induced CYP1A2 in rat liver and CYP2B and CYP3A families of isoforms in rat and mouse liver.

  9. Efficient liver repopulation of transplanted hepatocyte prevents cirrhosis in a rat model of hereditary tyrosinemia type I

    PubMed Central

    Zhang, Ludi; Shao, Yanjiao; Li, Lu; Tian, Feng; Cen, Jin; Chen, Xiaotao; Hu, Dan; Zhou, Yan; Xie, Weifen; Zheng, Yunwen; Ji, Yuan; Liu, Mingyao; Li, Dali; Hui, Lijian

    2016-01-01

    Hereditary tyrosinemia type I (HT1) is caused by a deficiency in the enzyme fumarylacetoacetate hydrolase (Fah). Fah-deficient mice and pigs are phenotypically analogous to human HT1, but do not recapitulate all the chronic features of the human disorder, especially liver fibrosis and cirrhosis. Rats as an important model organism for biomedical research have many advantages over other animal models. Genome engineering in rats is limited till the availability of new gene editing technologies. Using the recently developed CRISPR/Cas9 technique, we generated Fah−/− rats. The Fah−/− rats faithfully represented major phenotypic and biochemical manifestations of human HT1, including hypertyrosinemia, liver failure, and renal tubular damage. More importantly, the Fah−/− rats developed remarkable liver fibrosis and cirrhosis, which have not been observed in Fah mutant mice or pigs. Transplantation of wild-type hepatocytes rescued the Fah−/− rats from impending death. Moreover, the highly efficient repopulation of hepatocytes in Fah−/− livers prevented the progression of liver fibrosis to cirrhosis and in turn restored liver architecture. These results indicate that Fah−/− rats may be used as an animal model of HT1 with liver cirrhosis. Furthermore, Fah−/− rats may be used as a tool in studying hepatocyte transplantation and a bioreactor for the expansion of hepatocytes. PMID:27510266

  10. Efficient liver repopulation of transplanted hepatocyte prevents cirrhosis in a rat model of hereditary tyrosinemia type I.

    PubMed

    Zhang, Ludi; Shao, Yanjiao; Li, Lu; Tian, Feng; Cen, Jin; Chen, Xiaotao; Hu, Dan; Zhou, Yan; Xie, Weifen; Zheng, Yunwen; Ji, Yuan; Liu, Mingyao; Li, Dali; Hui, Lijian

    2016-01-01

    Hereditary tyrosinemia type I (HT1) is caused by a deficiency in the enzyme fumarylacetoacetate hydrolase (Fah). Fah-deficient mice and pigs are phenotypically analogous to human HT1, but do not recapitulate all the chronic features of the human disorder, especially liver fibrosis and cirrhosis. Rats as an important model organism for biomedical research have many advantages over other animal models. Genome engineering in rats is limited till the availability of new gene editing technologies. Using the recently developed CRISPR/Cas9 technique, we generated Fah(-/-) rats. The Fah(-/-) rats faithfully represented major phenotypic and biochemical manifestations of human HT1, including hypertyrosinemia, liver failure, and renal tubular damage. More importantly, the Fah(-/-) rats developed remarkable liver fibrosis and cirrhosis, which have not been observed in Fah mutant mice or pigs. Transplantation of wild-type hepatocytes rescued the Fah(-/-) rats from impending death. Moreover, the highly efficient repopulation of hepatocytes in Fah(-/-) livers prevented the progression of liver fibrosis to cirrhosis and in turn restored liver architecture. These results indicate that Fah(-/-) rats may be used as an animal model of HT1 with liver cirrhosis. Furthermore, Fah(-/-) rats may be used as a tool in studying hepatocyte transplantation and a bioreactor for the expansion of hepatocytes. PMID:27510266

  11. Hepatic lipase is localized at the parenchymal cell microvilli in rat liver.

    PubMed Central

    Breedveld, B; Schoonderwoerd, K; Verhoeven, A J; Willemsen, R; Jansen, H

    1997-01-01

    Hepatic lipase (HL) is thought to be located at the vascular endothelium in the liver. However, it has also been implicated in the binding and internalization of chylomicron remnants in the parenchymal cells. In view of this apparent discrepancy between localization and function, we re-investigated the localization of HL in rat liver using biochemical and immunohistochemical techniques. The binding of HL to endothelial cells was studied in primary cultures of rat liver endothelial cells. Endothelial cells bound HL in a saturable manner with high affinity. However, the binding capacity accounted for at most 1% of the total HL activity present in the whole liver. These results contrasted with earlier studies, in which non-parenchymal cell (NPC) preparations had been found to bind HL with a high capacity. To study HL binding to the different components of the NPC preparations, we separated endothelial cells, Kupffer cells and blebs by counterflow elutriation. Kupffer cells and endothelial cells showed a relatively low HL-binding capacity. In contrast, the blebs, representing parenchymal-cell-derived material, had a high HL-binding capacity (33 m-units/mg of protein) and accounted for more than 80% of the total HL binding in the NPC preparation. In contrast with endothelial and Kupffer cells, the HL-binding capacity of parenchymal cells could account for almost all the HL activity found in the whole liver. These data strongly suggest that HL binding occurs at parenchymal liver cells. To confirm this conclusion in situ, we studied HL localization by immunocytochemical techniques. Using immunofluorescence, we confirmed the sinusoidal localization of HL. Immunoelectron microscopy demonstrated that virtually all HL was located at the microvilli of parenchymal liver cells, with a minor amount at the endothelium. We conclude that, in rat liver, HL is localized at the microvilli of parenchymal cells. PMID:9020876

  12. Safety evaluation of mercury based Ayurvedic formulation (Sidh Makardhwaj) on brain cerebrum, liver & kidney in rats

    PubMed Central

    Kumar, Gajendra; Srivastava, Amita; Sharma, Surinder Kumar; Gupta, Yogendra Kumar

    2014-01-01

    Background & objectives: Sidh Makardhwaj (SM) is a mercury based Ayurvedic formulation used in rheumatoid arthritis and neurological disorders. However, toxicity concerns due to mercury content are often raised. Therefore, the present study was carried out to evaluate the effect of SM on brain cerebrum, liver and kidney in rats. Methods: Graded doses of SM (10, 50, 100 mg/kg), mercuric chloride (1 mg/kg) and normal saline were administered orally to male Wistar rats for 28 days. Behavioural parameters were assessed on days 1, 7, 14 and 28 using Morris water maze, passive avoidance, elevated plus maze and rota rod. Liver and kidney function tests were done on day 28. Animals were sacrificed and brain cerebrum acetylcholinesterase activity, levels of malondialdehyde (MDA), reduced glutathione (GSH) in brain cerebrum, liver, kidney were estimated. The levels of mercury in brain cerebrum, liver and kidney were estimated and histopathology of these tissues was also performed. Results: SM in the doses used did not cause significant change in neurobehavioural parameters, brain cerebrum AChE activity, liver (ALT, AST, ALP bilirubin) and kidney (serum urea and creatinine) function tests as compared to control. The levels of mercury in brain cerebrum, liver, and kidney were found to be raised in dose dependent manner. However, the levels of MDA and GSH in these tissues did not show significant changes at doses of 10 and 50 mg/kg. Also, there was no histopathological change in cytoarchitecture of brain cerebrum, liver, and kidney tissues at doses of 10 and 50 mg/kg. Interpretation & conclusions: The findings of the present study suggest that Sidh Makardhwaj upto five times the equivalent human dose administered for 28 days did not show any toxicological effects on rat brain cerebrum, liver and kidney. PMID:24927349

  13. Differential metabolism of 4-hydroxynonenal in liver, lung and brain of mice and rats

    SciTech Connect

    Zheng, Ruijin; Dragomir, Ana-Cristina; Mishin, Vladimir; Richardson, Jason R.; Heck, Diane E.; Laskin, Debra L.; Laskin, Jeffrey D.

    2014-08-15

    The lipid peroxidation end-product 4-hydroxynonenal (4-HNE) is generated in tissues during oxidative stress. As a reactive aldehyde, it forms Michael adducts with nucleophiles, a process that disrupts cellular functioning. Liver, lung and brain are highly sensitive to xenobiotic-induced oxidative stress and readily generate 4-HNE. In the present studies, we compared 4-HNE metabolism in these tissues, a process that protects against tissue injury. 4-HNE was degraded slowly in total homogenates and S9 fractions of mouse liver, lung and brain. In liver, but not lung or brain, NAD(P)+ and NAD(P)H markedly stimulated 4-HNE metabolism. Similar results were observed in rat S9 fractions from these tissues. In liver, lung and brain S9 fractions, 4-HNE formed protein adducts. When NADH was used to stimulate 4-HNE metabolism, the formation of protein adducts was suppressed in liver, but not lung or brain. In both mouse and rat tissues, 4-HNE was also metabolized by glutathione S-transferases. The greatest activity was noted in livers of mice and in lungs of rats; relatively low glutathione S-transferase activity was detected in brain. In mouse hepatocytes, 4-HNE was rapidly taken up and metabolized. Simultaneously, 4-HNE-protein adducts were formed, suggesting that 4-HNE metabolism in intact cells does not prevent protein modifications. These data demonstrate that, in contrast to liver, lung and brain have a limited capacity to metabolize 4-HNE. The persistence of 4-HNE in these tissues may increase the likelihood of tissue injury during oxidative stress. - Highlights: • Lipid peroxidation generates 4-hydroxynonenal, a highly reactive aldehyde. • Rodent liver, but not lung or brain, is efficient in degrading 4-hydroxynonenal. • 4-hydroxynonenal persists in tissues with low metabolism, causing tissue damage.

  14. No tumour-initiating risk associated with scAAV transduction in newborn rat liver.

    PubMed

    Gauttier, V; Pichard, V; Aubert, D; Kaeppel, C; Schmidt, M; Ferry, N; Conchon, S

    2013-07-01

    Delivery of recombinant adeno-associated virus (rAAV) vectors to the newborn liver is followed by a rapid loss of episomal vector copies because of hepatocyte proliferation. In selected hepatocytes, integration of rAAV genomes can lead to a sustained expression of the transgene. The safety of in vivo gene therapy with single-stranded AAV vectors has been questioned in a study reporting a high incidence of hepatocellular carcinoma, associated with provirus integration events in mice that receive an single-stranded AAV injection at birth. To investigate the tumour-initiating potential of the newly established self-complementary AAV (scAAV) vectors in the liver, groups of newborn rats received intravenous injection of a scAAV vector encoding the green fluorescent protein (GFP), or were injected with phosphate-buffered saline (PBS) or diethylnitrosamine (DEN), a well-known liver tumour initiator. The rats were fed on a diet containing 2-acetylaminofluorene, a potent liver tumour-promoting agent to accelerate the carcinogenic process. After 2 months, the animals were killed and their livers analysed. Preneoplastic nodules were identified by glutathion S-transferase-p (GSTp) staining, and GFP expression was detected by immunohistochemistry. Vector genome integration events were analysed. The numbers of GSTp-positive foci were comparable in the PBS and the scAAV-GFP groups and significantly higher in the DEN group. The proportion of GSTp-positive foci that also expressed GFP was low and in the range expected for random occurrence. No specific integration hot spots were detected by linear amplification-mediated-PCR in transduced liver. In conclusion, scAAV transduction of newborn rat liver does not trigger preneoplastic lesions suggesting an absence of liver tumourigenesis.

  15. Morphological and biochemical assessment of the liver response to excess dietary copper in Fischer 344 rats.

    PubMed Central

    Aburto, E M; Cribb, A E; Fuentealba, I C; Ikede, B O; Kibenge, F S; Markham, F

    2001-01-01

    The aim of this study was to determine the amount of excess dietary copper (Cu) necessary to experimentally induce liver lesions characteristic of Cu-associated disease in Fischer 344 rats. Male weanling Fischer 344 rats of uniform age were divided into 6 groups (n = 5) and fed a rodent diet containing 18 (control), 750, 1000, 1250, 1500, and 2000 microg/g Cu added as CuSO4. Rats were euthanized after 3 months on the experimental diets and their livers processed for histology, histochemistry, Cu analysis (by atomic absorption spectrophotometry), and quantification of malondialdehyde (MDA) by the thiobarbituric acid reaction. Hepatic Cu levels were significantly higher (P < 0.01) in rats receiving over 1000 microg/g Cu compared to the controls (means for each diet: control = 4.8 microg/g, 750 microg/g Cu = 39.6 microg/g, 1000 microg/g Cu = 111.2 microg/g, 1250 microg/g Cu = 389 microg/g, 1500 microg/g Cu = 509.4 microg/g, and 2000 microg/g Cu = 766 microg/g). Histological lesions increased gradually according to the level of dietary Cu. Significant morphologic changes (necrosis, portal inflammation, hyaline remnants) and reduced growth rate occurred in rats receiving over 1250 microg/g Cu. However, no significant differences were found for MDA levels between groups. The present study demonstrates that compared to other species, very high levels of excess dietary Cu are needed to induce significant liver injury in Fischer 344 rats. Increased MDA content was not detected in rats with morphologic evidence of liver damage, suggesting that lipid peroxidation may not play a major role in this model of Cu toxicity. Images Figure 2. Figure 3. Figure 4. PMID:11346262

  16. Protective effect of Xingnaojia formulation on rats with brain and liver damage caused by chronic alcoholism

    PubMed Central

    LI, SHUANG; WANG, SU; GUO, ZHI-GANG; HUANG, NING; ZHAO, FAN-RONG; ZHU, MO-LI; MA, LI-JUAN; LIANG, JIN-YING; ZHANG, YU-LIN; HUANG, ZHONG-LIN; WAN, GUANG-RUI

    2015-01-01

    The aim of this study was to observe the effect of a formulation of traditional Chinese medicine extracts known as Xingnaojia (XNJ) on the liver function, learning ability and memory of rats with chronic alcoholism and to verify the mechanism by which it protects the brain and liver. A rat model of chronic alcoholism was used in the study. The spatial learning ability and memory of the rats were tested. The rats were then sacrificed and their brains and hepatic tissues were isolated. The activity of superoxide dismutase (SOD) and levels of glutamate (Glu), N-methyl D-aspartate receptor subtype 2B (NR2B), cyclin-dependent kinase 5 (CDK5) and cannabinoid receptor 1 (CB1) in the hippocampus were analyzed. The ultrastructure of the hepatic tissue was observed by electron microscopy. In addition, the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in serum were tested and the levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and total cholesterol (TCHOL) were analyzed. XNJ enhanced the learning and memory of rats with chronic alcoholism. Treatment with XNJ increased the activity of SOD, and decreased the expression levels of NR2B mRNA and NR2B, CB1 and CDK5 proteins in the brain tissues compared with those in the model rats. It also increased the activity of ALDH in the serum and liver, decreased the serum levels of LDL, TG and TCHOL and increased the serum level of HDL. These results indicate that XNJ exhibited a protective effect against brain and liver damage in rats with chronic alcoholism. PMID:26640531

  17. Identification of a fibronectin receptor specific for rat liver endothelial cells

    SciTech Connect

    Johansson, S.; Gustafson, S.; Pertoft, H. )

    1987-10-01

    Antibodies raised against the fibronectin receptor of rat hepatocytes recognized one protein in immunoblotting of solubilized rat liver endothelial cells (LEC). The antibodies specifically precipitated a 200-kDa protein together with the 135-kDa component from {sup 125}I-labeled LEC. Spreading of LEC on fibronectin, but not on laminin or collagen, was inhibited by monovalent Fab fragments of the antibodies, implicating that the 135/200-kDa complex is a specific fibronectin receptor. The results indicate that LEC, hepatocytes, and fibroblasts of rat carry different fibronectin receptors, suggesting that the interaction of fibronectin with these cells may have different functional roles.

  18. ESTIMATING CHLOROFORM BIOTRANSFORMATION IN F-344 RAT LIVER USING IN VITRO TECHNIQUES AND PHARMACOKINETIC MODELING

    EPA Science Inventory

    ESTIMATING CHLOROFORM BIOTRANSFORMATION IN F-344 RAT LIVER USING IN VITRO TECHNIQUES AND PHARMACOKINETIC MODELING

    Linskey, C.F.1, Harrison, R.A.2., Zhao, G.3., Barton, H.A., Lipscomb, J.C4., and Evans, M.V2., 1UNC, ESE, Chapel Hill, NC ; 2USEPA, ORD, NHEERL, RTP, NC; 3 UN...

  19. Chronic iron overload in rats induces oval cells in the liver.

    PubMed Central

    Smith, P. G.; Yeoh, G. C.

    1996-01-01

    Liver damage induced by a variety of agents including hepatocarcinogens, alcohol, and virus induces proliferation of oval cells. In this study, iron overloading of the liver is used as a means of inducing liver damage over an extended period to ascertain whether it promotes the appearance of oval cells. Rats were fed a 2% carbonyl-iron-supplemented diet for 3 or 6 months. Extensive iron deposits appeared periportally in hepatocytes and some Kupffer cells. Iron deposition was less pronounced pericentrally. Small oval-like cells, morphologically and immunocytochemically similar to CDE-derived oval cells, were identified and quantified. They first emerged periportally and subsequently in small tracts or foci nearer central regions and stained positively for alpha-fetoprotein, pi-class glutathione S-transferase, and the embryonic form of pyruvate kinase. They contained very few iron deposits and were classified as iron free. The major difference between CDE- and iron-overload-derived oval cells was that the latter were negative for transferrin. This study shows that cellular changes occurring in iron-overloaded rat liver are similar to those observed in rats placed on a hepatocarcinogenic diet and in rats chronically exposed to alcohol. Images Figure 1 Figure 2 Figure 3 PMID:8701979

  20. Tissue inhibitor of metalloproteinase-1 and -2 RNA expression in rat and human liver fibrosis.

    PubMed Central

    Herbst, H.; Wege, T.; Milani, S.; Pellegrini, G.; Orzechowski, H. D.; Bechstein, W. O.; Neuhaus, P.; Gressner, A. M.; Schuppan, D.

    1997-01-01

    The remodeling of extracellular matrix during chronic liver disease may partially be attributed to altered activity of matrix metalloproteinases and their tissue inhibitors (TIMPs). Expression of TIMP-1 and -2 was studied by in situ hybridization combined with immunohistochemistry in rat (acute and chronic carbon tetrachloride intoxication and secondary biliary fibrosis) and human livers and on isolated rat hepatic stellate cells. TIMP-1 and -2 transcripts appeared in rat livers within 1 to 3 hours after intoxication, pointing to a role in the protection against accidental activation of matrix metalloproteinases, and were present at high levels in all fibrotic rat and human livers predominantly in stellate cells. TIMP-2 RNA distribution largely matched with previously reported patterns of matrix metalloproteinase-2 (72-kd gelatinase) expression, suggesting generation of a TIMP-2/matrix metalloproteinase-2 complex (large inhibitor of metalloproteinases). Isolated stellate cells expressed TIMP-1 and -2 RNA. Addition of transforming growth factor-beta 1 enhanced TIMP-1 and matrix metalloproteinase-2 RNA levels in vitro, whereas TIMP-2-specific signals were reduced, likely to result in a stoichiometric excess of matrix-metalloproteinase-2 over TIMP-2. In the context of previous demonstrations of transforming growth factor-beta 1 and matrix metalloproteinase-2 in vivo, these patterns suggest an intrahepatic environment permitting only limited matrix degradation, ultimately resulting in redistribution of extracellular matrix with relative accumulation of collagen type 1. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:9137090

  1. AN IMPROVED CELL FRACTIONATION PROCEDURE FOR THE PREPARATION OF RAT LIVER MEMBRANE-BOUND RIBOSOMES

    PubMed Central

    Adelman, M. R.; Blobel, Gunter; Sabatini, David D.

    1973-01-01

    A cell fractionation procedure is described which allows the preparation from rat liver of a rough microsome population containing almost 50% of the membrane-bound ribosomes of the tissue. The fraction is not contaminated with free ribosomes or smooth microsomes, and, by various other criteria, is suitable for studies of ribosome-membrane interaction. PMID:4345164

  2. [Biological function prediction of mir-210 in the liver of acute cold stress rat].

    PubMed

    Guo, Wen-Jin; Lian, Shuai; Guo, Jing-Ru; Zhai, Jun-Fei; Zhang, Yu-Chen; Li, Yue; Zhen, Li; Ji, Hong; Yang, Huan-Min

    2016-04-25

    The study was aimed to observe mir-210 expression in liver tissue of acute cold stress rat and predict the function of mir-210 in cold stress. Thirty SPF Wistar male rats which were 12-week-old and weighed (340 ± 20) g were used. The rats were pre-fed in normal room temperature for one week, and then were randomly divided into acute cold stress group at (4 ± 0.1) °C and normal control group at (24 ± 0.1) °C. After the rats were treated with cold stress for 12 h, the liver tissue was extracted and the gene expression of mir-210 was assayed using qRT-PCR. The results demonstrated that the gene expression of mir-210 was significantly enhanced in acute cold stress group compared with that in normal control group (n = 3, P < 0.01). The bioinformatics analysis showed that mir-210 has over hundreds of target genes and four kinds of target genes such as E2F3, RAD52, ISCU and Ephrin-A3 are more relative with liver cold stress. ISCU regulates the cell respiratory metabolism and Ephrin-A3 is related with cell proliferation and apoptosis. On the other hand, up-regulated mir-210 affects the DNA repairing mechanism which usually leads to genetic instabilities. Our results suggest that cold stress-induced up-regulation of mir-210 in liver harmfully influences cell growth, energy metabolism and hereditary.

  3. Deoxyribonucleic acid-dependent ribonucleic acid polymerase activity in rat liver after protein restriction.

    PubMed Central

    Andersson, G M; von der Decken, A

    1975-01-01

    Rats were fed for 6 days on a diet containing either 3 or 20% high-quality protein. Nuclei were isolated from liver and DNA-dependent RNA polymerases (EC 2.7.7.6) extracted with 1 M-(NH4)2SO4. The proteins were then precipitated with 3.5 M-(NH4)2SO4 and after dialysis applied to a DEAE-Sephadex column. The column was developed with a gradient of (NH4)2SO4. Polymerase I separated well from alpha-amanitin-sensitive polymerase II. The enzyme activities were compared between the two dietary groups. Rats that had received 3% protein showed a lower polymerase I activity per g wet wt. of liver, per mg of DNA and per mg of protein. Polymerase II was lower in activity per g wet wt. of liver and per mg of DNA, but was higher per mg of protein. Polyacrylamide-gel electrophoretograms showed a higher proportion of contaminating proteins in polymerase II fractions isolated from 20%-protein-fed rats. The data explain the lower activity obtained per mg of protein in these rats. It is concluded that a decrease in dietary protein content from 20 to 3% induces a fall in content and specific activity of RNA polymerase I and II in liver. PMID:1156400

  4. METABOLISM OF MYCLOBUTANIL AND TRIADIMEFON BY HUMAN AND RAT CYTOCHROME P450 ENZYMES AND LIVER MICROSOMES.

    EPA Science Inventory

    Metabolism of two triazole-containing antifungal azoles was studied using expressed human and rat cytochrome P450s (CYP) and liver microsomes. Substrate depletion methods were used due to the complex array of metabolites produced from myclobutanil and triadimefon. Myclobutanil wa...

  5. Effect of praseodymium on drug metabolism in rat liver smooth and rough endoplasmic reticulum.

    PubMed

    Arvela, P; von Lehmann, B; Grajewski, O; Oberdisse, E

    1980-07-15

    A small i.v. dose (3 mg/kg) of a light lanthanon, praseodymium, impairs the drug metabolizing capacity of both the smooth and rough fractions of rat liver endoplasmic reticulum. This decrease in the activity of drug metabolizing enzymes and in the amount of cytochromes P-450 and b5 is more pronounced in the rough endoplasmic reticulum fraction.

  6. An in vivo rat model for early development of colorectal cancer metastasis to liver.

    PubMed

    Robertson, John H P; Yang, Shi Yu; Iga, Arthur M; Seifalian, Alexander M; Winslet, Marc C

    2008-12-01

    At diagnosis of colorectal cancer, approximately 25% of the patients have established colorectal liver metastasis. Optimal management of disseminated disease requires therapies targeting multiple stages in hepatic colorectal cancer metastasis development. To facilitate this, biologically accurate in vivo models are required. Early colonic cancer liver metastases development was studied using BDIX and Sprague-Dawley rat strains with human HT29 and rat DHDK12 colonic cancer cell lines. Different cancer cell-host combinations were used. Rat DHDK12 was previously chemically induced in the BDIX rat. Real-time intra-vital microscopy was employed to analyse the early development of liver metastases in four groups (n = 6 per group) (HT29-BDIX, DHDK12-BDIX, HT29-SD and DHDK12-SD). Data were compared using one-way anova with Bonferroni's multiple comparison test. The total number of tumour cells visualized, adherent cells within the hepatic sinusoids, extravasated tumour cells and migration rates were significantly higher in the DHDK12-BDIX combination. Maximum number of visualized cells and maximum migration rate were also significantly higher in this group. No significant differences were observed in these experimental parameters among the other three groups or in the haemodynamic parameters among all groups. In conclusion, cancer cell line-host selection has a significant effect on early colonic cancer liver metastasis development.

  7. Hepatoprotective Effects of Panus giganteus (Berk.) Corner against Thioacetamide- (TAA-) Induced Liver Injury in Rats

    PubMed Central

    Wong, Wei-Lun; Abdulla, Mahmood Ameen; Chua, Kek-Heng; Kuppusamy, Umah Rani; Tan, Yee-Shin; Sabaratnam, Vikineswary

    2012-01-01

    Panus giganteus, a culinary and medicinal mushroom consumed by selected indigenous communities in Malaysia, is currently being considered for large scale cultivation. This study was undertaken to investigate the hepatoprotective effects of P. giganteus against thioacetamide- (TAA-) induced liver injury in Sprague-Dawley rats. The rats were injected intraperitoneally with TAA thrice weekly and were orally administered freeze-dried fruiting bodies of P. giganteus (0.5 or 1 g/kg) daily for two months, while control rats were given vehicle or P. giganteus only. After 60 days, rats administered with P. giganteus showed lower liver body weight ratio, restored levels of serum liver biomarkers and oxidative stress parameters comparable to treatment with the standard drug silymarin. Gross necropsy and histopathological examination further confirmed the hepatoprotective effects of P. giganteus. This is the first report on hepatoprotective effects of P. giganteus. The present study showed that P. giganteus was able to prevent or reduce the severity of TAA-induced liver injury. PMID:22649470

  8. Hepatoprotective activity of cinnamon ethanolic extract against CCI4-induced liver injury in rats

    PubMed Central

    Eidi, Akram; Mortazavi, Pejman; Bazargan, Maryam; Zaringhalam, Jalal

    2012-01-01

    The inner bark of cinnamon (Cinnamomum zeylanicum L.) is commonly used as a spice and has also been widely employed in the treatment and prevention of disease. The aim of the present study is to evaluate the protective effect of cinnamon bark extract against carbon tetrachloride (CCl4)-induced liver damage in male Wistar rats. Administration with cinnamon extracts (0.01, 0.05 and 0.1 g/kg) for 28 days significantly reduced the impact of CCl4 toxicity on the serum markers of liver damage, aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase. In addition, treatment of cinnamon extract resulted in markedly increased the levels of superoxide dismutase and catalase enzymes in rats. The histopathological studies in the liver of rats also supported that cinnamon extract markedly reduced the toxicity of CCl4 and preserved the histoarchitecture of the liver tissue to near normal. Thus, the results suggest that cinnamon extract acts as a potent hepatoprotective agent against CCl4 induced hepatotoxicity in rats. PMID:27547174

  9. Combined effects of fluoride and cadmium on liver and kidney function in male rats.

    PubMed

    Zhang, Junmin; Song, Jingjuan; Zhang, Jun; Chen, Xiao; Zhou, Meixia; Cheng, Guang; Xie, Xinyou

    2013-12-01

    It has been shown that cadmium and fluoride may both have adverse effects on liver and kidney functions, but most studies focus on a single agent. In this study, we observed the effects of cadmium and fluoride on liver and kidney functions using a rat model. Total of 24 Sprague-Dawley male rats were divided into four groups, one control group and three exposure groups that were given cadmium (50 mg/L) and fluoride (100 mg/L) alone or in combination via drinking water. At the 12th week, urine, blood, and kidney tissues were collected. Aspartate transaminase, alanine transaminase (ALT), urinary β2-microglobulin, and albumin were determined. Contents of malondialdehyde (MDA) and superoxide dismutase (SOD) in liver and kidney homogenates were measured to evaluate oxidative stress. There was a significant increase in serum ALT and urinary β2-microglobulin of rats in exposure groups compared with control. Serum ALT and urinary β2-microglobulin of rats exposed to cadmium and fluoride in combination was significantly higher than those treated with cadmium alone and fluoride alone. SOD declined significantly and MDA increased in combination group compared with control and those treated with cadmium and fluoride alone. Cadmium and fluoride co-exposure increase the liver and kidney damage compared with that exposed to cadmium or fluoride alone.

  10. A NOVEL S-ADENOSYL-L-METHIONINE: ARSENIC (III) METHYLTRANSFERASE FROM RAT LIVER CYTOSOL

    EPA Science Inventory

    A Novel S-Adenosyl-L-methionine: Arsenic(III) Methyltransferase from Rat Liver Cytosol
    Shan Lin, Qing Shi, F. Brent Nix, Miroslav Styblo, Melinda A. Beck, Karen M. Herbin-Davis, Larry L. Hall, Josef B. Simeonsson, and David J. Thomas
    S-adenosyl-L-methionine (AdoMet): ar...

  11. Antioxidant activity and hepatoprotective potential of Hammada scoparia against ethanol-induced liver injury in rats.

    PubMed

    Bourogaa, Ezzeddine; Nciri, Riadh; Mezghani-Jarraya, Raoudha; Racaud-Sultan, Claire; Damak, Mohamed; El Feki, Abdelfattah

    2013-06-01

    The present work was aimed at studying the antioxidative activity and hepatoprotective effects of methanolic extract (ME) of Hammada scoparia leaves against ethanol-induced liver injury in male rats. The animals were treated daily with 35 % ethanol solution (4 g kg(-1) day(-1)) during 4 weeks. This treatment led to an increase in the lipid peroxidation, a decrease in antioxidative enzymes (catalase, superoxide dismutase, and glutathione peroxidase) in liver, and a considerable increase in the serum levels of aspartate and alanine aminotransferase and alkaline phospahatase. However, treatment with ME protects efficiently the hepatic function of alcoholic rats by the considerable decrease in aminotransferase contents in serum of ethanol-treated rats. The glycogen synthase kinase-3 β was inhibited after ME administration, which leads to an enhancement of glutathione peroxidase activity in the liver and a decrease in lipid peroxidation rate by 76 %. These biochemical changes were consistent with histopathological observations, suggesting marked hepatoprotective effect of ME. These results strongly suggest that treatment with methanolic extract normalizes various biochemical parameters and protects the liver against ethanol induced oxidative damage in rats. PMID:22893526

  12. CHLORAL HYDRATE DECREASES GAP JUNCTION COMMUNICATION IN RAT LIVER EPITHELIAL CELLS

    EPA Science Inventory

    Chloral hydrate decreases gap junction communication in rat liver epithelial cells

    Gap junction communication (GJC) is involved in controlling cell proliferation and differentiation. Connexins (Cx) that make up these junctions are composed of a closely related group of m...

  13. Activation of ras oncogene in aflatoxin-induced rat liver carcinogenesis.

    PubMed Central

    Sinha, S; Webber, C; Marshall, C J; Knowles, M A; Proctor, A; Barrass, N C; Neal, G E

    1988-01-01

    The presence of activated transforming genes was investigated in four primary aflatoxin-induced rat liver tumors in male Fischer rats, in two cell lines generated from such tumors, in an epithelial liver-derived nontransformed cell line, and in the latter cell line after transformation by aflatoxin B1 in vitro. When DNA extracted from these sources was transfected into NIH 3T3 cells, negative results were obtained from focus assays. Cotransfection of these DNA samples with a gene for resistance to G418, followed by selection for resistance to that antibiotic, and tumorigenicity testing in nude mice demonstrated DNA-mediated transfer of the neoplastic phenotype in all cases except for DNA from the nontransformed cell line. DNA extracted from these primary nude mouse tumors used in a secondary round of transfection with NIH 3T3 cells gave positive results in focus assays, which were conserved through succeeding rounds of transfection. By use of appropriate radiolabeled probes, activated ras oncogenes were detected in all samples. N-ras activation was detected in three of the primary rat liver tumors and both hepatoma cell lines. Ki-ras activation was detected in one primary rat liver tumor, and Ha-ras activation was detected in the cell line transformed in vitro with activated aflatoxin B1. The activated Ki-ras oncogene was further characterized by use of synthetic oligonucleotide probes and was shown to contain a G----A transition at the second nucleotide in codon 12. Images PMID:3287372

  14. Effect of fipronil on energy metabolism in the perfused rat liver.

    PubMed

    de Medeiros, Hyllana Catarine Dias; Constantin, Jorgete; Ishii-Iwamoto, Emy Luiza; Mingatto, Fábio Erminio

    2015-07-01

    Fipronil is an insecticide used to control pests in animals and plants that can causes hepatotoxicity in animals and humans, and it is hepatically metabolized to fipronil sulfone by cytochrome P-450. The present study aimed to characterize the effects of fipronil (10-50μM) on energy metabolism in isolated perfused rat livers. In fed animals, there was increased glucose and lactate release from glycogen catabolism, indicating the stimulation of glycogenolysis and glycolysis. In the livers of fasted animals, fipronil inhibited glucose and urea production from exogenous l-alanine, whereas ammonia and lactate production were increased. In addition, fipronil at 50μM concentration inhibited the oxygen uptake and increased the cytosolic NADH/NAD⁺ ratio under glycolytic conditions. The metabolic alterations were found both in livers from normal or proadifen-pretreated rats revealing that fipronil and its reactive metabolites contributed for the observed activity. The effects on oxygen uptake indicated that the possible mechanism of toxicity of fipronil involves impairment on mitochondrial respiratory activity, and therefore, interference with energy metabolism. The inhibitory effects on oxygen uptake observed at the highest concentration of 50μM was abolished by pretreatment of the rats with proadifen indicating that the metabolites of fipronil, including fipronil sulfone, acted predominantly as inhibitors of respiratory chain. The hepatoxicity of both the parent compound and its reactive metabolites was corroborated by the increase in the activity of lactate dehydrogenase in the effluent perfusate in livers from normal or proadifen-pretreated rats.

  15. Absence of Nitric-oxide Synthase in Sequentially Purified Rat Liver Mitochondria*

    PubMed Central

    Venkatakrishnan, Priya; Nakayasu, Ernesto S.; Almeida, Igor C.; Miller, R. Timothy

    2009-01-01

    Data, both for and against the presence of a mitochondrial nitric-oxide synthase (NOS) isoform, is in the refereed literature. However, irrefutable evidence has not been forthcoming. In light of this controversy, we designed studies to investigate the existence of the putative mitochondrial NOS. Using repeated differential centrifugation followed by Percoll gradient fractionation, ultrapure, never frozen rat liver mitochondria and submitochondrial particles were obtained. Following trypsin digestion and desalting, the mitochondrial samples were analyzed by nano-HPLC-coupled linear ion trap-mass spectrometry. Linear ion trap-mass spectrometry analyses of rat liver mitochondria as well as submitochondrial particles were negative for any peptide from any NOS isoform. However, recombinant neuronal NOS-derived peptides from spiked mitochondrial samples were easily detected, down to 50 fmol on column. The protein calmodulin (CaM), absolutely required for NOS activity, was absent, whereas peptides from CaM-spiked samples were detected. Also, l-[14C]arginine to l-[14C]citrulline conversion assays were negative for NOS activity. Finally, Western blot analyses of rat liver mitochondria, using NOS (neuronal or endothelial) and CaM antibodies, were negative for any NOS isoform or CaM. In conclusion, and in light of our present limits of detection, data from carefully conducted, properly controlled experiments for NOS detection, utilizing three independent yet complementary methodologies, independently as well as collectively, refute the claim that a NOS isoform exists within rat liver mitochondria. PMID:19372221

  16. Protection effect of kallistatin on carbon tetrachloride-induced liver fibrosis in rats via antioxidative stress.

    PubMed

    Huang, Xiaoping; Wang, Xiao; Lv, Yinghui; Xu, Luli; Lin, Junsheng; Diao, Yong

    2014-01-01

    Prolonged inflammation and oxidative stress are emerging as key causes of pathological wound healing and the development of liver fibrosis. We have investigated the effects of recombinant human kallistatin, produced in Pichia. pastoris, on preventing carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Daily administration of kallistatin prevented development of CCl4-induced liver fibrosis, which was evidenced by histological study. In all kallistatin treated rats, activation of hepatic stellate cells (HSC) as assessed by s-smooth muscle actin staining was attenuated, TGF- β1 expression was inhibited, class I serum biomarkers associated with the process of fibrogenesis, such as hyaluronic acid, laminin, and procollagen III, were lowered, compared with that in the model control group. Furthermore, residual hepatic functional reserve was improved by kallistatin treatment. CCl4 induced elevation of malondialdehyde level and reduced superoxide dismutase activity in the liver, while kallistatin reduced these oxidative parameters. We also investigated the effects of kallistatin on rat primary HSC and LX-2, the human HSC cell line. Kallistatin scavenged H2O2-induced ROS in the LX-2 cells, and suppressed the activation of primary HSC. These results suggest recombinant human kallistatin might be a promising drug candidate for therapeutic intervention of liver fibrosis. PMID:24558397

  17. Effects of silymarin on the resolution of liver fibrosis induced by carbon tetrachloride in rats.

    PubMed

    Tsai, J H; Liu, J Y; Wu, T T; Ho, P C; Huang, C Y; Shyu, J C; Hsieh, Y S; Tsai, C C; Liu, Y C

    2008-07-01

    Silymarin, a standardized extract of the milk thistle (Silybum marianum), has a long tradition as a herbal remedy, and was introduced as a hepatoprotective agent a few years ago. However, the therapeutic effects of silymarin remain undefined. Carbon tetrachloride (CCl4) is a xenobiotic used extensively to induce oxidative stress and is one of the most widely used hepatic toxins for experimental induction of liver fibrosis in the laboratory. In this study, we investigated the restoration of the CCl4-induced hepatic fibrosis by high dose of silymarin in rats. After treatment with oil (as normal group; n = 6) or CCl4 [as model (n = 7) and therapeutic (n = 7) groups] by intragastric delivery for 8 weeks for the induction of liver fibrosis, the rats in the normal and model group were administered orally normal saline four times a week for 3 weeks whilst the therapeutic group received silymarin (200 mg/kg). The histopathological changes were observed with Masson staining. The results showed that the restoration of the CCl4-induced damage of liver fibrosis in the therapeutic group was significantly increased as compared to that in the model group. Moreover, silymarin significantly decreased the elevation of aspartate aminotransferase (AST), alanine aminotransferase, and alkaline phosphatase in serum, and also reversed the altered expressions of alpha-smooth muscle actin in liver tissue. Therefore, these findings indicated that silymarin may have the potential to increase the resolution of the CCl4-induced liver fibrosis in rats.

  18. Fatty acid synthase-positive hepatocytes and subsequent steatosis in rat livers by irinotecan

    PubMed Central

    SAWANO, TAKEYUKI; SHIMIZU, TAKESHI; YAMADA, TOSHIYUKI; NANASHIMA, NAOKI; MIURA, TAKUYA; MOROHASHI, SATOKO; KUDO, DAISUKE; HUI, FENG MAO; KIJIMA, HIROSHI; HAKAMADA, KENICHI; TSUCHIDA, SHIGEKI

    2015-01-01

    Using a rat model, we investigated factors contributing to the pathogenesis of irinotecan-associated fatty liver disease. Male Sprague-Dawley rats were administered 200 mg/kg irinotecan by intraperitoneal injection on days 1–4, but not on days 5–7. This schedule was repeated 3 times. Rats were sacrificed 4, 18 and 25 days after the last injection, and liver steatosis was evaluated by hematoxylin and eosin (H&E) staining, microarray analysis and immunohistochemistry. Panacinar intrahepatocyte vacuoles were absent on days 4 and 25, but present on day 18, and this alteration was more prominent around the bile ducts than the central veins. Microarray analysis showed that the expression of genes involved in the synthesis of cholesterol and fatty acids was upregulated on day 4. Immunohistochemistry detected fatty acid synthase (Fasn)-strongly positive hepatocytes as well as the activation of liver progenitor cells on day 4, whereas intracellular vacuoles were evident in carbonic anhydrase 3 (CA3)-positive hepatocytes on day 18. Thus, irinotecan-induced liver steatosis was preceded by Fasn-strongly-positive hepatocytes and liver progenitor cell activation. The magnitude of the decrease in the number of Fasn-strongly positive hepatocytes between days 4 and 18 was similar to that of the increase in the number of CA3-positive hepatocytes accompanying vacuoles. PMID:25708528

  19. Low G preconditioning reduces liver injury induced by high +Gz exposure in rats

    PubMed Central

    Shi, Bin; Feng, Zhi-Qiang; Li, Wen-Bing; Zhang, Hong-Yi

    2015-01-01

    AIM: To investigate the effect of repeated lower +Gz exposure on liver injury induced by high +Gz exposure in rats. METHODS: Sixty male Wister rats were randomly divided into a blank control group, a low G preconditioning group (LG) (exposed to +4 Gz/5 min per day for 3 d before +10 Gz/5 min exposure), and a +10 Gz/5 min group (10G) (n = 20 in each group). Blood specimens and liver tissue were harvested at 0 h and 6 h after +10 Gz/5 min exposure. Liver function was analyzed by measuring serum alanine transaminase (ALT) and aspartate aminotransferase (AST) levels, and liver injury was further assessed by histopathological observation. Malondialdehyde (MDA), superoxide dismutase (SOD) and Na+-K+-ATPase were determined in hepatic tissue. RESULTS: The group LG had lower ALT, AST, and MDA values at 0 h after exposure than those in group 10G. SOD values and Na+-K+-ATPase activity in the LG group were higher than in group 10G 0 h post-exposure. Hepatocyte injury was significantly less in group LG than in group 10G on histopathological evaluation. CONCLUSION: It is suggested that repeated low +Gz exposure shows a protective effect on liver injury induced by high +Gz exposure in rats. PMID:26074692

  20. Transmission electron microscopy of heart and liver tissues from rats fed with gums arabic and tragacanth.

    PubMed

    Anderson, D M; Ashby, P; Busuttil, A; Kempson, S A; Lawson, M E

    1984-04-01

    Transmission electron microscopy has been used to examine the ultrastructure of rat hearts and livers after diet supplementation with (a) 0, 0.5, 1.5, 2.5 and 3.5% (w/w) gum tragacanth (GT) for 91 days, (b) 0 and 1% GT for 5 days (c) 0, 1, 4 and 8% (w/w) gum arabic (GA) for 28 days. The preparation and scrutiny of the electron micrographs was undertaken by two independent teams of specialists. There were no detectable abnormalities in any of the organelles in the heart and liver specimens from any of the test animals and no inclusions nor other pathological changes were observed. All micrographs showed normal, healthy tissues; particular attention was given to the mitochondria in hepatocytes as they serve as sensitive indicators of the health and state of activity of cells. In addition, the data obtained from assays of the microsomal protein and cytochrome P-450 content of the livers showed that GA and GT did not cause inductive effects. These results do not support earlier suggestions, based on in vitro assays, that GA and GT cause changes in the function of rat heart and liver mitochondria and liver microsomes; however, they confirm a report by Zbinden that the ingestion of GT does not produce abnormalities in the cardiac function of rats.

  1. Lycopene Improves Diet-Mediated Recuperation in Rat Model of Nonalcoholic Fatty Liver Disease.

    PubMed

    Piña-Zentella, Rosa María; Rosado, Jorge L; Gallegos-Corona, Marco A; Madrigal-Pérez, Luis Alberto; García, Olga P; Ramos-Gomez, Minerva

    2016-06-01

    The aim of the present study was to evaluate the synergic effect of lycopene (LYC) treatment with a dietary control in a nonalcoholic fatty liver disease (NAFLD) model induced with a high-fat diet (HFD). Sprague-Dawley rats were fed during 4 weeks with a normal diet (ND·4w) or an HFD (HFD·4w) to produce an NAFLD model. Then, rats from the ND·4w group continued during 4 weeks with the same diet (ND·8w), and rats from HFD were fed during 4 weeks with an ND (HFD·4w+ND·4w) or an ND plus LYC (HFD·4w+ND+LYC·4w). LYC (20 mg/kg) was administered daily by gavage. ND and ND+LYC diets partially reverted the following alterations due to HFD: liver weight, serum low-density lipoproteins (LDL), hepatic total cholesterol (TC), and catalytic activity of hepatic superoxide dismutase, catalase, and glutathione peroxidase, as well as macroscopic and microscopic images of livers. A higher recuperation to reach normality was obtained with ND+LYC in: liver weight, hepatic TC, serum LDL, and, in some instances, macroscopic and microscopic images of livers. Failures to recovery with both NDs were observed for malondialdehyde level and serum aspartate aminotransferase activity. Taken together, the results from this study suggest the potentially protective role of LYC against NAFLD; however, more clinical trials are needed to support this idea. PMID:27214602

  2. Structural and ultrastructural study of rat liver influenced by electromagnetic radiation.

    PubMed

    Holovská, K; Almášiová, V; Cigánková, V; Beňová, K; Račeková, E; Martončíková, M

    2015-01-01

    Mobile communication systems are undoubtedly an environmental source of electromagnetic radiation (EMR). There is an increasing concern regarding the interactions of EMR with the humans. The aim of this study was to examine the effects of EMR on Wistar rat liver. Mature rats were exposed to electromagnetic field of frequency 2.45 GHz and mean power density of 2.8 mW/cm2 for 3 h/d for 3 wk. Samples of the liver were obtained 3 h after the last irradiation and processed histologically for light and transmission electron microscopy. Data demonstrated the presence of moderate hyperemia, dilatation of liver sinusoids, and small inflammatory foci in the center of liver lobules. Structure of hepatocytes was not altered and all described changes were classified as moderate. Electron microscopy of hepatocytes revealed vesicles of different sizes and shapes, lipid droplets, and proliferation of smooth endoplasmic reticulum. Occasionally necrotizing hepatocytes were observed. Our observations demonstrate that EMR exposure produced adverse effects on rat liver.

  3. Iron bioavailability of rats fed liver, lentil, spinach and their mixtures.

    PubMed

    Rewashdeh, Abdullah Y; El-Qudah, Jafar M; Al-Dmoor, Hanee; Al-Qudah, Maisa M; Mamkagh, Amer M; Tarawneh, Khaled A; Hawari, Azmi D; Dababneh, Basem F; Al-Bakheit, Alaa A; Haddad, Moawya A

    2009-02-15

    To study the effects of dietary iron source (basal diet-FeSO4 x 7H2O, liver, lentil, spinach, liver + lentil, liver+spinach and lentil+spinach) on iron bioavailability, fifty-six Albino Sprague Dawley derived male 21 days old rats were fed on iron-deficient diet (7.8 mg Fe kg(-1) diet) and the mentioned seven iron containing diets (40 mg Fe kg(-1) diet) for 10 days. Rats fed liver diet showed higher iron apparent absorption (52.1%), hemoglobin (Hb) gain (0.94 g/100 mL), Hb-iron gain (1.2 mg), Hb-regeneration efficiency (HRE%) (50.8%), relative efficiency of HRE% (106.5%), packed cell volume gain (2.22%) and mean corpuscular hemoglobin concentration (0.64 g dL(-1)). Liver resulted in an increase in these parameters when mixed with lentil and spinach diets. However, rats fed iron free diet showed the higher dry matter absorption.

  4. Protection Effect of Kallistatin on Carbon Tetrachloride-Induced Liver Fibrosis in Rats via Antioxidative Stress

    PubMed Central

    Huang, Xiaoping; Wang, Xiao; Lv, Yinghui; Xu, Luli; Lin, Junsheng; Diao, Yong

    2014-01-01

    Prolonged inflammation and oxidative stress are emerging as key causes of pathological wound healing and the development of liver fibrosis. We have investigated the effects of recombinant human kallistatin, produced in Pichia. pastoris, on preventing carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Daily administration of kallistatin prevented development of CCl4-induced liver fibrosis, which was evidenced by histological study. In all kallistatin treated rats, activation of hepatic stellate cells (HSC) as assessed by s-smooth muscle actin staining was attenuated, TGF- β1 expression was inhibited, class I serum biomarkers associated with the process of fibrogenesis, such as hyaluronic acid, laminin, and procollagen III, were lowered, compared with that in the model control group. Furthermore, residual hepatic functional reserve was improved by kallistatin treatment. CCl4 induced elevation of malondialdehyde level and reduced superoxide dismutase activity in the liver, while kallistatin reduced these oxidative parameters. We also investigated the effects of kallistatin on rat primary HSC and LX-2, the human HSC cell line. Kallistatin scavenged H2O2-induced ROS in the LX-2 cells, and suppressed the activation of primary HSC. These results suggest recombinant human kallistatin might be a promising drug candidate for therapeutic intervention of liver fibrosis. PMID:24558397

  5. Effects of Chamomilla recutita flavonoids on age-related liver sphingolipid turnover in rats.

    PubMed

    Babenko, Nataliya A; Shakhova, Elena G

    2006-01-01

    The increased sphingolipid turnover in the liver is associated with elevation of free radical production and state of chronic inflammation at old age. Plant polyphenols are reported to exhibit antioxidant and anti-inflammatory effects. In the present paper, the lipids contents and ceramide production in the liver and hepatocytes as well as the correction of sphingolipid metabolism at old age using the mixture of Chamomilla recutita flavonoids (chamiloflan) or apigenin-7-glucoside or luteolin-7-glucoside alone have been investigated. To study the sphingolipids turnover, the [14C]serine-pre-labeled hepatocytes and [14C-methyl]- or [14C]palmitate-pre-labeled sphingomyelin (SM) and ceramide were used. The ceramide content was higher in the liver and hepatocytes of 24- and 27-28-month-old animals as compared to adult 3-month-old Wistar rats. An addition of flavonoids to the culture medium did not influence significantly on the lipids contents and metabolism in the isolated hepatocytes. The administration of flavonoids to old rats decreased the elevated neutral and acid SMases activities and ceramide mass and did not affect both the lipid content in the liver of adult animals and ceramide conversion to the sphingosine or SM. These results suggest that the SMases play a key role in the flavonoid-induced decrease of ceramide levels in the liver of old rats. PMID:16183236

  6. Involvement of zinc in cell-free protein synthesizing systems from rat liver

    SciTech Connect

    Hicks, S.E.; Wallwork, J.C.

    1986-03-05

    There are conflicting reports in the literature concerning the role of zinc in protein synthesis. This study presents evidence for the direct involvement of zinc in the translation of polypeptide chains in rats. Cell-free systems for incorporation of amino acids into acid-insoluble proteins were prepared from livers of three populations of rats: (1) rats fed ad libitum a diet containing 25 ppm zinc; (2) rats fed a diet containing less than 1 ppm zinc and (3) rats pair-fed a diet containing 25 ppm zinc. The diets contained 20% egg white and were enriched with biotin. Distilled deionized drinking water was given. The animals were maintained on the regimen for 45 days with precautions to limit zinc contamination. Group 2 showed typical signs of zinc deficiency, including decreased bone zinc. In vitro systems containing liver polysomes and a pH5 precipitate enzyme fraction indicated that the synthetic ability of systems isolated from zinc-deficient rats was considerably depressed, resulting in incorporation of amino acids 15 to 30% less than systems from pair-fed rats and 30 to 50% less than ad libitum-fed control animals. The results of crossover experiments performed by mixing polysome and enzyme fractions from the different groups indicated that the defect is due primarily to the pH precipitate enzyme fraction and not the polysomes.

  7. Ultrasound imaging in an experimental model of fatty liver disease and cirrhosis in rats

    PubMed Central

    2010-01-01

    Background Domestic dogs and cats are very well known to develop chronic hepatic diseases, including hepatic lipidosis and cirrhosis. Ultrasonographic examination is extensively used to detect them. However, there are still few reports on the use of the ultrasound B-mode scan in correlation with histological findings to evaluate diffuse hepatic changes in rodents, which represent the most important animal group used in experimental models of liver diseases. The purpose of this study was to determine the reliability of ultrasound findings in the assessment of fatty liver disease and cirrhosis when compared to histological results in Wistar rats by following up a murine model of chronic hepatic disease. Results Forty Wistar rats (30 treated, 10 controls) were included. Liver injury was induced by dual exposure to CCl4 and ethanol for 4, 8 and 15 weeks. Liver echogenicity, its correlation to the right renal cortex echogenicity, measurement of portal vein diameter (PVD) and the presence of ascites were evaluated and compared to histological findings of hepatic steatosis and cirrhosis. Liver echogenicity correlated to hepatic steatosis when it was greater or equal to the right renal cortex echogenicity, with a sensitivity of 90%, specificity of 100%, positive and negative predictive values of 100% and 76.9% respectively, and accuracy of 92.5%. Findings of heterogeneous liver echogenicity and irregular surface correlated to liver cirrhosis with a sensitivity of 70.6%, specificity of 100%, positive and negative predictive values of 100% and 82.1% respectively, and accuracy of 87.5%. PVD was significantly increased in both steatotic and cirrhotic rats; however, the later had greater diameters. PVD cut-off point separating steatosis from cirrhosis was 2.1 mm (sensitivity of 100% and specificity of 90.5%). One third of cirrhotic rats presented with ascites. Conclusion The use of ultrasound imaging in the follow-up of murine diffuse liver disease models is feasible and

  8. Collagen arrangement in space of Disse correlates with fluid flow in normal and cirrhotic rat livers.

    PubMed

    Poonkhum, Raksawan; Showpittapornchai, Udomsri; Pradidarcheep, Wisuit

    2015-02-01

    Little is known about collagen arrangement in the space of Disse was related to the fluid flow both in normal and cirrhotic liver. We examined the changes in the arrangement of type-I collagen in thioacetamide-induced cirrhotic rat livers with immunohistochemistry and SEM after maceration of the noncollagenous tissues with NaOH. The sparse bundles of collagen fibers in the spaces of Disse were mostly elongated fibers with a disorganized arrangement in each nodule. They connected with the broad fibrous septa. Based on a comparison of the architecture of the collagen fibers and the established flow of fluid in the space of Disse, we hypothesize that the fluid in the space of Disse streams along collagen fibers in all directions to broad fibrous septa. The appearance of perinodular plexus in cirrhotic rat livers probably helps to reduce portal hypertension.

  9. Blood and liver acetaldehyde concentration in rats following acetaldehyde inhalation and intravenous and intragastric ethanol administration

    SciTech Connect

    Watanabe, A.; Hobara, N.; Nagashima, H.

    1986-10-01

    Ethanol is metabolized to acetaldehyde, a highly reactive product of ethanol oxidation. Ethanol might be blended with gasoline and used as a fuel in the future; biohazard of acetaldehyde inhalation must be discussed. Recent improvements in our ability to measure acetaldehyde levels in blood and various tissues have made the assessment of acetaldehyde's role in alcoholic organ intoxication possible. Blood and liver acetaldehyde concentrations in rats were reported as being linearly correlated following intragastric ethanol administration. Acetaldehyde was administered by inhalation to study its toxicity. However, liver concentrations following the inhalation was not investigated. The present communication describes the relationship between blood and liver acetaldehyde concentrations in rats following acetaldehyde inhalation and different routes of ethanol administration.

  10. Improvement of Rat Survival and Liver Mitochondrial Function in Biliary Obstruction After Treatment With Sodium Thiosulfate

    PubMed Central

    Myslovaty, B.; Kyzer, S.; Levinsky, H.; Chaimoff, C.

    1995-01-01

    The exact cause of liver failure occurring after long standing biliary obstruction is not known. Impairment of hepatic mitochondrial respiration was postulated in some studies. Sodium thiosulphate (STS) is known to have a protective effect on liver function during administration of hepatotoxic chemotherapy. In the present experimental study the effect of treatment with STS in the presence of obstructive jaundice was studied by determination of the survival rate of rats subjected to biliary obstruction and by polarographic determination of the hepatic mitochondrial function. Treatment with STS was found to result in a significant improvement in rats' survival rate (p < 0.05). Polarography demonstrated significant preservation of mitochondrial respiratory capacity after treatment with STS. The results of the present study show that the deterioration in liver function in the presence of biliary obstruction is probably caused by impairment of mitochondrial respiration. This may be preserved by treatment with STS. The exact explanation of its effect is not yet clear. PMID:18612479

  11. Improvement of rat survival and liver mitochondrial function in biliary obstruction after treatment with sodium thiosulfate.

    PubMed

    Myslovaty, B; Kyzer, S; Levinsky, H; Chaimoff, C

    1995-01-01

    The exact cause of liver failure occurring after long standing biliary obstruction is not known. Impairment of hepatic mitochondrial respiration was postulated in some studies. Sodium thiosulphate (STS) is known to have a protective effect on liver function during administration of hepatotoxic chemotherapy. In the present experimental study the effect of treatment with STS in the presence of obstructive jaundice was studied by determination of the survival rate of rats subjected to biliary obstruction and by polarographic determination of the hepatic mitochondrial function. Treatment with STS was found to result in a significant improvement in rats' survival rate (p < 0.05). Polarography demonstrated significant preservation of mitochondrial respiratory capacity after treatment with STS. The results of the present study show that the deterioration in liver function in the presence of biliary obstruction is probably caused by impairment of mitochondrial respiration. This may be preserved by treatment with STS. The exact explanation of its effect is not yet clear. PMID:18612479

  12. The 14-day repeated dose liver micronucleus test with methapyrilene hydrochloride using young adult rats.

    PubMed

    Inoue, Kenji; Ochi, Akimu; Koda, Akira; Wako, Yumi; Kawasako, Kazufumi; Doi, Takaaki

    2015-03-01

    The repeated dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect genotoxic hepatocarcinogens that can be integrated into a general toxicity study. The assay methods were thoroughly validated by 19 Japanese facilities. Methapyrilene hydrochloride (MP), known to be a non-genotoxic hepatocarcinogen, was examined in the present study. MP was dosed orally at 10, 30 and 100mg/kg/day to 6-week-old male Crl:CD (SD) rats daily for 14 days. Treatment with MP resulted in an increase in micronucleated hepatocytes (MNHEPs) with a dosage of only 100mg/kg/day. At this dose level, cytotoxicity followed by regenerative cell growth was noted in the liver. These findings suggest that MP may induce clastogenic effects indirectly on the liver or hepatotoxicity of MP followed by regeneration may cause increase in spontaneous incidence of MNHEPs.

  13. Expression and localization of regenerating gene I in a rat liver regeneration model

    SciTech Connect

    Wang Jingshu; Koyota, Souichi; Zhou, Xiaoping; Ueno, Yasuharu; Ma Li; Kawagoe, Masami; Koizumi, Yukio; Okamoto, Hiroshi; Sugiyama, Toshihiro

    2009-03-13

    Regenerating gene (Reg) I has been identified as a regenerative/proliferative factor for pancreatic islet cells. We examined Reg I expression in the regenerating liver of a rat model that had been administered 2-acetylaminofluorene and treated with 70% partial hepatectomy (2-AAF/PH model), where hepatocyte and cholangiocyte proliferation was suppressed and the hepatic stem cells and/or hepatic progenitor cells were activated. In a detailed time course study of activation of hepatic stem cells in the 2-AAF/PH model, utilizing immunofluorescence staining with antibodies of Reg I and other cell-type-specific markers, we found that Reg I-expressing cells are present in the bile ductules and increased during regeneration. Reg I-expressing cells were colocalized with CK19, OV6, and AFP. These results demonstrate that Reg I is significantly upregulated in the liver of the 2-AAF/PH rat model, accompanied by the formation of bile ductules during liver regeneration.

  14. Biosynthesis of thiamine triphosphate and identification of thiamine diphosphate-binding proteins of rat liver hyaloplasm

    SciTech Connect

    Voskoboev, A.I.; Chernikevich, I.P.

    1986-03-10

    The nature of the proteins of rat liver hyaloplasm that bind ThDP* was studied. When injection of (/sup 14/C)thiamine was used as the marker, an electrophoretically homogeneous protein preparations, containing (/sup 14/C)ThDP, identified as transketolase, was isolated from the soluble fraction of the liver. No other nonenzymatic proteins that bind ThDP and might serve as the substrate in the synthesis of ThTP were detected in the hyaloplasm. It was shown that transfer of the phosphate group by rat liver ThDP kinase occurs to the free ThDP, and not to protein-bound ThDP, as was previously asserted.

  15. Molecular cloning of cDNA for rat liver gap junction protein

    PubMed Central

    1986-01-01

    An affinity-purified antibody directed against the 27-kD protein associated with isolated rat liver gap junctions was produced. Light and electron microscopic immunocytochemistry showed that this antigen was localized specifically to the cytoplasmic surfaces of gap junctions. The antibody was used to select cDNA from a rat liver library in the expression vector lambda gt11. The largest cDNA selected contained 1,494 bp and coded for a protein with a calculated molecular mass of 32,007 daltons. Northern blot analysis indicated that brain, kidney, and stomach express an mRNA with similar size and homology to that expressed in liver, but that heart and lens express differently sized, less homologous mRNA. PMID:3013898

  16. Effect of liver fatty acid binding protein on fatty acid movement between liposomes and rat liver microsomes.

    PubMed Central

    McCormack, M; Brecher, P

    1987-01-01

    Although movement of fatty acids between bilayers can occur spontaneously, it has been postulated that intracellular movement is facilitated by a class of proteins named fatty acid binding proteins (FABP). In this study we have incorporated long chain fatty acids into multilamellar liposomes made of phosphatidylcholine, incubated them with rat liver microsomes containing an active acyl-CoA synthetase, and measured formation of acyl-CoA in the absence or presence of FABP purified from rat liver. FABP increased about 2-fold the accumulation of acyl-CoA when liposomes were the fatty acid donor. Using fatty acid incorporated into liposomes made either of egg yolk lecithin or of dipalmitoylphosphatidylcholine, it was found that the temperature dependence of acyl-CoA accumulation in the presence of FABP correlated with both the physical state of phospholipid molecules in the liposomes and the binding of fatty acid to FABP, suggesting that fatty acid must first desorb from the liposomes before FABP can have an effect. An FABP-fatty acid complex incubated with microsomes, in the absence of liposomes, resulted in greater acyl-CoA formation than when liposomes were present, suggesting that desorption of fatty acid from the membrane is rate-limiting in the accumulation of acyl-CoA by this system. Finally, an equilibrium dialysis cell separating liposomes from microsomes on opposite sides of a Nuclepore filter was used to show that liver FABP was required for the movement and activation of fatty acid between the compartments. These studies show that liver FABP interacts with fatty acid that desorbs from phospholipid bilayers, and promotes movement to a membrane-bound enzyme, suggesting that FABP may act intracellularly by increasing net desorption of fatty acid from cell membranes. PMID:3446187

  17. Insulin resistance and delayed clearance of peptide hormones in cirrhotic rat liver.

    PubMed

    Shankar, T P; Drake, S; Solomon, S S

    1987-06-01

    Clearance of porcine insulin, glucagon, and human growth hormone was measured in intact perfused cirrhotic and normal rat livers. Binding and degradation of 125I-insulin by hepatocytes isolated from cirrhotic and normal livers were also studied. The half-lives (t1/2) of immunoreactive insulin and glucagon were 14.0 +/- 3.1 and 9.6 +/- 2.1 min in normal livers and 26.0 +/- 6.1 and 25.0 +/- 7.1 min in cirrhotic livers (P less than 0.001). Insulin binding and degradation by hepatocytes from control and cirrhotic livers showed no significant differences. Intraportal insulin infusion in perfusion studies suppressed glucagon-stimulated increases in glucose output from control livers but failed to suppress glucose production by cirrhotic livers, suggesting the presence of hepatic insulin resistance in cirrhosis. Impaired clearance of insulin and glucagon by the intact cirrhotic liver and normal binding and degradation of insulin by isolated hepatocytes suggest that factors such as intrahepatic fibrosis and shunting and postbinding defects may be responsible for the impaired hormone clearance and hepatic insulin resistance. PMID:3296781

  18. Recovery of liver function in partially hepatectomized rats evaluated by aminopyrine demethylation capacity

    SciTech Connect

    Sendama, I.; de Hemptinne, B.; Lambotte, L.

    1985-07-01

    Aminopyrine demethylation was investigated in rats after a 70% hepatectomy to assess possible parallelism between the recovery of mass and function. Tests were performed by analyzing UCO2 exhalation from 0.1 microCi per 100 gm of body weight of (dimethylamine- UC)aminopyrine given intraperitoneally with incremental doses of unlabeled drug. Early after 70% hepatectomy, Vmax was reduced by 52%. This discordance between mass and function was not due to extrahepatic aminopyrine demethylation, since liver exclusion reduced demethylation of aminopyrine to nearly nil. Whether it results from increased liver blood flow in the remnant liver is less clear. The early increase in Vmax could be related to a hepatotrophic factor of splanchnic origin which increased after partial hepatectomy and decreased after portacaval shunt. After the early period, Vmax, expressed per gram of actual liver weight, returned to control range. Throughout regeneration (4 to 144 hr), no modification was observed in Km nor in cytochrome P-450 concentration. Enzymatic induction with phenobarbital increased the demethylation capacity more than liver weight in intact and regenerating liver. Except for the first hours after partial hepatectomy or after enzymatic induction, the aminopyrine demethylation capacity directly correlated with liver mass and may be useful in evaluating liver regeneration in vivo.

  19. Insulin resistance and delayed clearance of peptide hormones in cirrhotic rat liver

    SciTech Connect

    Shankar, T.P.; Drake, S.; Solomon, S.S.

    1987-06-01

    Clearance of porcine insulin, glucagon, and human growth hormone was measured in intact perfused cirrhotic and normal rat livers. Binding and degradation of /sup 125/I-insulin by hepatocytes isolated from cirrhotic and normal livers were also studied. The half-lives (t/sub 1/2/) of immunoreactive insulin and glucagon were 14.0 +/- 3.1 and 9.6 +/- 2.1 min in normal livers and 26.0 +/- 6.1 and 25.0 +/- 7.1 min in cirrhotic livers. Insulin binding and degradation by hepatocytes from control and cirrhotic livers showed no significant differences. Intraportal insulin infusion in perfusion studies suppressed glucagon-stimulated increases in glucose output from control livers but failed to suppress glucose production by cirrhotic livers, suggesting the presence of hepatic insulin resistance in cirrhosis. Impaired clearance of insulin and glucagon by the intact cirrhotic liver and normal binding and degradation of insulin by isolated hepatocytes suggest that factors such as intrahepatic fibrosis and shunting and postbinding defects may be responsible for the impaired hormone clearance and hepatic insulin resistance.

  20. Ethanol-induced impairment of hepatic glycoprotein secretion in the isolated rat liver perfusion model

    SciTech Connect

    Volentine, G.D.; Ogden, K.A.; Tuma, D.J.; Sorrell, M.F.

    1987-05-01

    The authors have previously shown that acute administration of ethanol inhibits hepatic glycoprotein secretion in vivo. This ethanol-induced effect appears to be mediated by its reactive metabolite, acetaldehyde. Since hormonal influences and vascular changes can not be controlled in vivo during ethanol administration, they investigated the effect of ethanol in the isolated perfused liver model. Rat liver from fed animals was perfused with oxygenated KRB at 3 ml/min/g liver for 4 hrs. Since ethanol inhibits proteins synthesis in vitro, protein acceptor pool size was equalized in both ethanol and control perfused livers with 1 mM cycloheximide. /sup 3/H-glucosamine was used to label hepatic secretory glycoproteins in the perfusate. Colchicine, a known inhibitor of protein secretion, impaired the secretion of labeled glycoproteins with a concomitant retention of these export proteins in the liver; therefore, confirming the authors secretory model. Ethanol (50 mM) inhibited the appearance of glucosamine-labeled glycoproteins by 60% into the perfusate as compared to control livers. Pretreatment of animals with cyanamide (an aldehyde dehydrogenase inhibitor) further potentiated this effect of ethanol in the isolated perfused liver. These data suggest that ethanol inhibits hepatic glycoprotein secretion in the isolated liver perfusion model, and this ethanol-induced impairment appears to be mediated by acetaldehyde.

  1. Protective effects of (-)-epigallocatechin-3-gallate against acetaminophen-induced liver injury in rats).

    PubMed

    Yao, Hsien-Tsung; Yang, Yu-Chi; Chang, Chen-Hui; Yang, Hui-Ting; Yin, Mei-Chin

    2015-09-01

    (-)-Epigallocatechin-3-gallate (EGCG) is the most abundant catechin with various biological activities found in tea. In this study, the effects of EGCG on the metabolism and toxicity of acetaminophen in rat liver were investigated. Male Sprague-Dawley rats were fed a controlled diet without or with EGCG (0.54 %, w/w) for 1 week and were then intraperitoneally injected with acetaminophen (1 g/kg body weight) and killed after 12 h. Concentrations of acetaminophen and its conjugates in plasma and liver were then determined. The cytochrome P450 (CYP) and phase II enzymes activities were also evaluated. Rats fed the EGCG diet had lower plasma alanine aminotransferase and aspartate aminotransferase activities, as indices of hepatotoxicity, after acetaminophen treatment. Morphological damage by acetaminophen was lower in rats fed the EGCG diet. In addition, EGCG significantly reduced hepatic activities of midazolam 1-hydroxylation (CYP3A), nitrophenol 6-hydroxylase (CYP2E1), UDP-glucurosyltransferase, and sulfotransferase. Finally, EGCG feeding reduced acetaminophen-glucuronate and acetaminophen-glutathione contents in plasma and liver. These results indicate that EGCG feeding may reduce the metabolism and toxicity of acetaminophen in rats. PMID:26264479

  2. Direct and indirect effects of kisspeptin on liver oxidant and antioxidant systems in young male rats.

    PubMed

    Aydin, M; Oktar, S; Yonden, Z; Ozturk, O H; Yilmaz, B

    2010-06-01

    Kisspeptin is a recently discovered hypothalamic peptide which plays an important role in the central control of reproductive functions. We have investigated direct and indirect effects of kisspeptin on the liver oxidative stress in young male rats. Twenty-four rats were divided into four groups (n = 6/group). First group served as control and received saline. Kisspeptin-10 was administered to the animals in the second group (20 nmol/rat/day), for a period of 7 days. Rats were given only one dose gosereline (0.9 mg/rat), a GnRH agonist in the third group. The last group received kisspeptin-10 with gosereline. The activities of catalase, superoxide dismutase (SOD), xanthine oxidase (XO), adenosine deaminase (AD) and level of malondialdehyde were studied in liver tissue. Serum samples were separated for total antioxidant capacity (TAC), total oxidant status (TOS), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, blood urea nitrogen (BUN), colesterol, high-density lipoprotein (HDL) and triglyceride. Kisspeptin increased the activities of SOD and catalase (p < 0.05). When compared to the control group, the levels of malondialdehyde, TOS and AST were lower, but levels of BUN, cholesterole, HDL and AD were higher in the other three groups (p < 0.05). In conclusion, our findings suggest that kisspeptin may have antioxidant and thus protective effects on the liver tissue. PMID:20517893

  3. Integrative proteomic and microRNA analysis of the priming phase during rat liver regeneration.

    PubMed

    Geng, Xiaofang; Chang, Cuifang; Zang, Xiayan; Sun, Jingyan; Li, Pengfei; Guo, Jianli; Xu, Cunshuan

    2016-01-10

    The partial hepatectomy (PH) model provides an effective medium for study of liver regeneration (LR). Considering that LR is regulated by microRNAs (miRNAs), investigation of the regulatory role of miRNAs is critical for revealing how regenerative processes are initiated and controlled. Using high-throughput sequencing technology, we examined miRNA expression profiles of the regenerating rat liver after PH, and found that 23 miRNAs were related to rat LR. Among them, several miRNAs were significantly altered at 2h and 6h after PH, corresponding to the priming phase of LR. Furthermore, we examined the protein profiles in the regenerating rat liver at 2h and 6h after PH by iTRAQ coupled with LC-MS/MS, and found that 278 proteins were significantly changed. Subsequently, an integrative proteomic and microRNA analysis by Ingenuity Pathway Analysis 9.0 (IPA) software showed that miR-125a, miR-143, miR-150, miR-181c, miR-182, miR-183, miR-199a, miR-429 regulated the priming phase of rat LR by modulating the expression of proteins involved in networks critical for cell apoptosis, cell survival, cell cycle, inflammatory response, metabolism, etc. Thus, our studies provide novel evidence for a functional molecular network populated by the down-regulated targets of the up-regulated miRNAs in the priming phase of rat LR.

  4. Natural killer (NK) activity of pit cells perfused from livers of rats treated with ethanol

    SciTech Connect

    Albornoz, L.; Jones, J.M.; Crutchfield, C.; Veech, R.L. Univ. of Arkansas Medical Sciences, Little Rock )

    1991-03-11

    The liver is the major site of ethanol (ETOH) metabolism. Liver sinusoids contain lymphocytes with NK activity. The authors treated LEW rats for 2 weeks with i.p. injection of 1.25 ml 25% ETOH/kg 3 times/week and 5% ETOH in drinking water. Livers were perfused at 5-fold physiological pressure and cells obtained were banded on 1.077 density Ficoll. Their cytotoxicity was tested against {sup 51}Cr-labeled YAC-1 or U937 and compared to spleen and blood lymphocytes. In untreated rats, pit cell NK activity was 2-fold that of splenic lymphocytes and 4-fold that of blood lymphocytes. Compared to controls, ETOH-treated rats exhibited a 30 to 90% rise in pit cell NK activity detected with YAC-1 or U937 targets. The pit cell enhanced NK activity in ETOH-treated rats was further increased if polyinosinicpolycytidilic acid was injection i.p. 18 hours before the assay. Blood and spleen lymphocyte NK activity of ETOH-treated rats was also greater than in controls. There was no evidence that ETOH merely redistributed lymphocytes among the tissues. Although ETOH acutely inhibits NK activity in vitro, chronic ETOH increases in vivo.

  5. Direct and indirect effects of kisspeptin on liver oxidant and antioxidant systems in young male rats.

    PubMed

    Aydin, M; Oktar, S; Yonden, Z; Ozturk, O H; Yilmaz, B

    2010-06-01

    Kisspeptin is a recently discovered hypothalamic peptide which plays an important role in the central control of reproductive functions. We have investigated direct and indirect effects of kisspeptin on the liver oxidative stress in young male rats. Twenty-four rats were divided into four groups (n = 6/group). First group served as control and received saline. Kisspeptin-10 was administered to the animals in the second group (20 nmol/rat/day), for a period of 7 days. Rats were given only one dose gosereline (0.9 mg/rat), a GnRH agonist in the third group. The last group received kisspeptin-10 with gosereline. The activities of catalase, superoxide dismutase (SOD), xanthine oxidase (XO), adenosine deaminase (AD) and level of malondialdehyde were studied in liver tissue. Serum samples were separated for total antioxidant capacity (TAC), total oxidant status (TOS), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, blood urea nitrogen (BUN), colesterol, high-density lipoprotein (HDL) and triglyceride. Kisspeptin increased the activities of SOD and catalase (p < 0.05). When compared to the control group, the levels of malondialdehyde, TOS and AST were lower, but levels of BUN, cholesterole, HDL and AD were higher in the other three groups (p < 0.05). In conclusion, our findings suggest that kisspeptin may have antioxidant and thus protective effects on the liver tissue.

  6. Immunological basis of septal fibrosis of the liver in Capillaria hepatica-infected rats.

    PubMed

    Lemos, Q T; Magalhães-Santos, I F; Andrade, Z A

    2003-09-01

    Rats infected with the helminth Capillaria hepatica regularly develop septal fibrosis of the liver similar to that induced by repeated ip injections of pig serum. Fibrosis starts when the focal parasitic lesions begin to show signs of resorption, thus suggesting an immunologically mediated pathogenesis of this fibrosis. To explore this possibility, the development of C. hepatica-related hepatic fibrosis was observed in rats exposed to worm antigens from the first neonatal day onward. Wistar rats (150 g) were either injected ip with an extract of C. hepatica eggs (protein concentration: 1 mg/ml) or received immature eggs by gavage from the first neonatal day until adult life and were then infected with 500 embryonated eggs. Changes were monitored on the basis of serum levels of anti-worm antibodies and hepatic histopathology. Rats submitted to immunological oral tolerance markedly suppressed C. hepatica-related serum antibodies and septal fibrosis of the liver when infected with the helminth later on. Tolerance trials with ip injections of worm antigens gave essentially negative results. The partial suppression of septal fibrosis of the liver after the induction of immunological tolerance to C. hepatica antigens in rats indicates an immunological basis for the fibrosis and emphasizes the importance of immunological factors in the pathogenesis of hepatic fibrosis.

  7. Oxidative and conjugative metabolism of xenobiotics by livers of cattle, sheep, swine and rats.

    PubMed

    Smith, G S; Watkins, J B; Thompson, T N; Rozman, K; Klaassen, C D

    1984-02-01

    Homogenate preparations from fresh livers of cattle, sheep, swine and rats were assayed for microsomal cytochrome P-450 content, for mixed-function oxidase activities and for a wide array of conjugative activities using numerous xenobiotic substrates. Results show that hepatic enzymatic capabilities toward xenobiotics do not parallel phylogenetic classifications, thus strengthening the view that most of the comparative data available at present is more descriptive than predictive of relationships among species. Livestock species differed widely from rats in having lower activities of benzo(alpha)pyrene hydroxylase, glutathione S-transferase and acetyltransferase toward isoniazid and sulfamethazine and UDP-glucuronosyl-transferase toward bilirubin. Acetyltransferase activities toward beta-naphthylamine and 2-aminofluorene were not detected in livers of livestock species studied. Cattle livers were remarkably high in activities of styrene oxide hydrolase, ethoxyresorufin O-deethylase, 2-naphthol sulfotransferase and p-aminobenzoic acid acetyltransferase; but notably low in activity of glutathione-S-transferase toward sulfobromophthalein and 1,2-dichloro-4-nitrobenzene. Swine livers had low activity of glutathione-S-transferase toward four of six substrates and low acetyltransferase activity toward four of five substrates. Sheep livers generally were higher than cattle livers in sulfo- and UDP-glucuronsyltransferase activities and lower in acetyl- and glutathionyl-S-transferase. Findings emphasize the risk of error in extra-polations among species and in extrapolations among substrates.

  8. Procedure for Decellularization of Rat Livers in an Oscillating-pressure Perfusion Device.

    PubMed

    Hillebrandt, Karl; Polenz, Dietrich; Butter, Antje; Tang, Peter; Reutzel-Selke, Anja; Andreou, Andreas; Napierala, Hendrik; Raschzok, Nathanael; Pratschke, Johann; Sauer, Igor M; Struecker, Benjamin

    2015-01-01

    Decellularization and recellularization of parenchymal organs may enable the generation of functional organs in vitro, and several protocols for rodent liver decellularization have already been published. We aimed to improve the decellularization process by construction of a proprietary perfusion device enabling selective perfusion via the portal vein and/or the hepatic artery. Furthermore, we sought to perform perfusion under oscillating surrounding pressure conditions to improve the homogeneity of decellularization. The homogeneity of perfusion decellularization has been an underestimated factor to date. During decellularization, areas within the organ that are poorly perfused may still contain cells, whereas the extracellular matrix (ECM) in well-perfused areas may already be affected by alkaline detergents. Oscillating pressure changes can mimic the intraabdominal pressure changes that occur during respiration to optimize microperfusion inside the liver. In the study presented here, decellularized rat liver matrices were analyzed by histological staining, DNA content analysis and corrosion casting. Perfusion via the hepatic artery showed more homogenous results than portal venous perfusion did. The application of oscillating pressure conditions improved the effectiveness of perfusion decellularization. Livers perfused via the hepatic artery and under oscillating pressure conditions showed the best results. The presented techniques for liver harvesting, cannulation and perfusion using our proprietary device enable sophisticated perfusion set-ups to improve decellularization and recellularization experiments in rat livers.

  9. Gene silencing of 4-1BB by RNA interference inhibits acute rejection in rats with liver transplantation.

    PubMed

    Shi, Yang; Hu, Shuqun; Song, Qingwei; Yu, Shengcai; Zhou, Xiaojun; Yin, Jun; Qin, Lei; Qian, Haixin

    2013-01-01

    The 4-1BB signal pathway plays a key role in organ transplantation tolerance. In this study, we have investigated the effect of gene silencing of 4-1BB by RNA interference (RNAi) on the acute rejection in rats with liver transplantation. The recombination vector of lentivirus that contains shRNA targeting the 4-1BB gene (LV-sh4-1BB) was constructed. The liver transplantation was performed using the two-cuff technique. Brown-Norway (BN) recipient rats were infected by the recombinant LVs. The results showed that gene silencing of 4-1BB by RNAi downregulated the 4-1BB gene expression of the splenic lymphocytes in vitro, and the splenic lymphocytes isolated from the rats with liver transplantation. LV-sh4-1BB decreased the plasma levels of liver injury markers including AST, ALT, and BIL and also decreased the level of plasma IL-2 and IFN- γ in recipient rats with liver transplantation. Lentivirus-mediated delivery of shRNA targeting 4-1BB gene prolonged the survival time of recipient and alleviated the injury of liver morphology in recipient rats with liver transplantation. In conclusion, our results demonstrate that gene silencing of 4-1BB by RNA interference inhibits the acute rejection in rats with liver transplantation.

  10. Relationship between alpha-1 receptors and cations in rat liver plasma membranes

    SciTech Connect

    Smart, J.L.

    1986-01-01

    The influence of cations on binding of (/sup 3/H)-prazosin (PRZ), an alpha-1 specific antagonist, to alpha receptor sites in rat liver plasma membranes was examined. All cations tested were able to produce dose-dependent shifts to lower affinity binding sites for PRZ. The maximum number of binding sites was also observed to be altered. Inclusion of cations resulted in a slower observed rate constant for association as well as a delay in the dissociation of specifically bound PRZ following the addition of phentolamine. In contrast, the ability of (-)-norepinephrine to displace PRZ was enhanced by the addition of cations. The influence of alpha-1 receptor stimulation on Na/sup +//K/sup +/-ATPase activity in rat liver was examined by two methods - rat liver plasma membrane Na/sup +//K/sup +/-ATPase activity following liver perfusion in situ and /sup 86/Tb uptake in rat liver slices. The activity of the Na/sup +/ pump was found to be biphasic following exposure to phenylephrine (PE), an alpha-1 agonist. Stimulation (35%) was present over the first two minutes, while activity was inhibited over the interval of 5 to 10 minutes of continued PE exposure. Both phases were blocked by prazosin. The influence of DAG and protein kinase C (PKC) in alpha-1 receptor modulation of the Na/sup +/ pump was studied by employing 4-beta-phorbol (PMA), a phorbol ester which activates PKC. Perfusion of livers with PMA in situ or incubation with slices yielded inhibition of ATPase activity in membranes and /sup 86/Rb uptake in that was qualitatively and quantitatively similar to PE. These results suggest cations may influence receptor function in vivo and in vitro and the inhibitory effects of PE on the sodium pump may be mediated through PKC.

  11. Proinflammatory Liver and Antiinflammatory Intestinal Mediators Involved in Portal Hypertensive Rats

    PubMed Central

    Aller, Maria Angeles; Vara, Elena; Garcia, Cruz; Palma, Maria Dolores; Arias, Jorge L.; Nava, Maria Paz; Arias, Jaime

    2005-01-01

    Proinflammatory (TNF-α, IL-1β, and NO) and antiinflammatory (IL-10, CO) levels were assayed in serum, liver, and small bowel in order to verify a hypothetic inflammatory etiopathogeny of portal hypertension that could be the cause of its evolutive heterogeneity. Male Wistar rats were divided into one control group (n = 11) and one group with a triple stenosing ligation of the portal vein (n = 23) after 28 days of evolution. In one subgroup of portal hypertensive rats, portal pressure, collateral venous circulation, mesenteric vasculopathy, and liver and spleen weights were determined. In the remaining rats with portal hypertension TNF-α, IL-1β, and IL-10 were quantified in liver and ileum by enzyme-linked immunosorbent assay. NO synthase activity was studied in liver and ileum. CO and NO were measured in portal and systemic blood by spectrophotometry and Griess reaction, respectively. Portal hypertensive rats with mayor spleen weight show hepatomegaly and mayor development of collateral circulation. Ileum release of IL-10 (0.30 ± 0.12 versus 0.14 ± 0.02 pmol/mg protein; P < .01) is associated with a liver production of both proinflammatory mediators (TNF-α: 2 ± 0.21 versus 1.32 ± 0.60 pmol/mg protein; P < .05, IL-1β: 19.17 ± 2.87 versus 5.96 ± 1.84 pmol/mg protein; P = .005, and NO: 132.10 ± 34.72 versus 61.05 ± 8.30 nmol/mL; P = .005) and an antiinflammatory mediator (CO: 6.49 ± 2.99 versus 3.03 ± 1.59 pmol/mL; P = .005). In short-term prehepatic portal hypertension a gut-liver inflammatory loop, which could be fundamental in the regulation both of the portal pressure and of its complications, could be proposed. PMID:16030393

  12. ATP metabolism in rat liver chronically treated with ethanol and high fat

    SciTech Connect

    Miyamoto, K.; French, S.W.

    1986-03-01

    Five pairs of Wistar male rats weighing about 350 g were continuously infused with a liquid diet in which 25-35% of total calories was derived from fat, plus ethanol or isocaloric dextrose through gastrostomy cannulas for 3 wks to 3.5 mos. Mean ethanol intake was 12.9 +/- 0.7 g/kg B.W. (55% of total calories). High blood alcohol levels (BAL, 342 +/- 151 mg/dl) were maintained. The liver showed severe steatosis (4+) in all the ethanol-fed rats (ER). Two had mild focal mononuclear cell infiltration, one had mild fibrosis and one had spotty necrosis. Mild steatosis (1+) was seen in 4 out of 5 pair-fed control rats (CR). Serum ALT was significantly higher in ER (129 +/- 44 U) compared with Cr (59 +/- 30 U) or rats fed chow ad lib (NR) (48 +/- 26 U). Biopsied liver tissue was used to measure the concentration of adenine nucleotides by HPLC (6 pairs). There was a significant decrease of ATP in ER (1.7 +/- 0.3 ..mu..mol/g liver) as compared to CR (2.5 +/- 0.5 ..mu..mol/g) or NR (2.8 +/- 0.2 ..mu..mol/g, n = 6). There was no significant change in the ADP or AMP content, however. The total adenylate pool of the liver was also significantly reduced in ER when compared to that of CR or NR (3.2 +/- 0.4, 4.0 +/- 0.5 and 4.3 +/- 0.2 ..mu..mol/g liver, respectively). Adeynlate energy charge (E.C.) of the ER livers (0.71 +/- 0.05) was significantly reduced compared to NR (0.77 +/- 0.02) but not with CR (0.75 +/- 0.06). The results indicate that ethanol decreases the level of ATP as well as the biological mechanism to compensate for the lowered level.

  13. Endogenous carbon monoxide downregulates hepatic cystathionine-γ-lyase in rats with liver cirrhosis

    PubMed Central

    GUO, SHI-BIN; DUAN, ZHI-JUN; WANG, QIU-MING; ZHOU, QIN; LI, QING; SUN, XIAO-YU

    2015-01-01

    The aim of the present study was to investigate the effect of endogenous carbon monoxide (CO) on the hydrogen sulfide/cystathionine-γ-lyase (H2S/CSE) pathway in cirrhotic rat livers. The rats were allocated at random into four groups: Sham, cirrhosis, cobalt protoporphyrin (CoPP) and zinc protoporphyrin IX (ZnPP). The expression of hepatic CSE mRNA was evaluated using a quantitative polymerase chain reaction, while CSE protein expression was determined using immunohistochemical analysis. Hematoxylin and eosin staining was performed for the histological evaluation of liver fibrosis. The levels of H2S, alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL) and carboxyhemoglobin (COHb) in the arterial blood were determined, in addition to the portal vein pressure. The mRNA and protein expression levels of hepatic CSE and the serum levels of H2S were significantly decreased in the cirrhosis group compared with those in the sham group (P<0.05). Compared with the cirrhosis group, rats in the ZnPP group had significantly lower levels of serum ALT, AST and TBIL, arterial COHb and hepatic fibrosis, while hepatic CSE expression and the production of H2S were significantly increased (P<0.05). The CoPP group exhibited decreased hepatic CSE expression and H2S production, but aggravated hepatic function and fibrosis (P<0.05). In conclusion, the H2S/CSE pathway is involved in the formation of liver cirrhosis and serves a crucial function in protecting liver cells against the progression of liver fibrosis. Endogenous CO downregulates hepatic CSE mRNA and protein expression and the production of H2S in rats with liver cirrhosis. PMID:26668593

  14. Effects of Fatty Liver Induced by Excess Orotic Acid on B-Group Vitamin Concentrations of Liver, Blood, and Urine in Rats.

    PubMed

    Shibata, Katsumi; Morita, Nobuya; Kawamura, Tomoyo; Tsuji, Ai; Fukuwatari, Tsutomu

    2015-01-01

    Fatty liver is caused when rats are given orotic acid of the pyrimidine base in large quantities. The lack of B-group vitamins suppresses the biosynthesis of fatty acids. We investigated how orotic acid-induced fatty liver affects the concentrations of liver, blood, and urine B-group vitamins in rats. The vitamin B6 and B12 concentrations of liver, blood, and urine were not affected by orotic acid-induced fatty liver. Vitamin B2 was measured only in the urine, but was unchanged. The liver, blood, and urine concentrations of niacin and its metabolites fell dramatically. Niacin and its metabolites in the liver, blood, and urine were affected as expected. Although the concentrations of vitamin B1, pantothenic acid, folate, and biotin in liver and blood were decreased by orotic acid-induced fatty liver, these urinary excretion amounts showed a specific pattern toward increase. Generally, as for the typical urinary excretion of B-group vitamins, these are excreted when the body is saturated. However, the ability to sustain vitamin B1, pantothenic acid, folate, and biotin decreased in fatty liver, which is hypothesized as a specific phenomenon. This metabolic response might occur to prevent an abnormally increased biosynthesis of fatty acids by orotic acid.

  15. Identification and differential expression of microRNAs associated with fat deposition in the liver of Wistar rats with nonalcoholic fatty liver disease.

    PubMed

    Zhang, Deqing; Wang, Yuqian; Ji, Zhibin; Wang, Zhonghua

    2016-07-01

    The exact mechanism underlying hepatic steatosis in nonalcoholic fatty liver disease (NAFLD) is not clear. Clarifying the full repertoire of microRNAs (miRNAs) in NAFLD rat liver would enhance our understanding of NAFLD pathogenesis. In this study, miRNA expression levels were analyzed in liver tissue from NAFLD Wistar rats, with normal Wistar rats as negative controls. Small RNA libraries were constructed for each sample. A total of 173 conservative miRNAs and 68 potential miRNA candidates were identified. Significant differences in the expression levels of 101 conserved miRNAs were identified between the two groups. The results of GO annotation and KEGG pathway analysis revealed that some miRNAs were likely involved in the process of liver fat deposition. This study represents the first global miRNA profiling of NAFLD Wistar rat livers, and expands the miRNA repertoire for normal livers. Our findings suggest that miRNAs play important roles in liver fat deposition.

  16. Hepatic iron deprivation prevents spontaneous development of fulminant hepatitis and liver cancer in Long-Evans Cinnamon rats.

    PubMed

    Kato, J; Kobune, M; Kohgo, Y; Sugawara, N; Hisai, H; Nakamura, T; Sakamaki, S; Sawada, N; Niitsu, Y

    1996-08-15

    Several clinical studies have suggested that excess hepatic iron accumulation is a progressive factor in some liver diseases including chronic viral hepatitis and hemochromatosis. However, it is not known whether iron-induced hepatotoxicity may be directly involved in hepatitis, cirrhosis, and liver cancer. The Long-Evans Cinnamon (LEC) rat, which accumulates excess copper in the liver as in patients with Wilson's disease, is of a mutant strain displaying spontaneous hemolysis, hepatitis, and liver cancer. We found previously that LEC rats harbored an additional abnormality: accumulation of as much iron as copper in the liver. In the present study, we compared the occurrence of hepatitis and liver cancer in LEC rats fed an iron-deficient diet (ID) with those in rats fed a regular diet (RD). The RD group showed rapid increments of hepatic iron concentrations as the result of hemolysis, characteristics of fulminant hepatitis showing apoptosis, and a 53% mortality rate. However, no rats in the ID group died of fulminant hepatitis. Hepatic iron, especially "free" iron concentration and the extent of hepatic fibrosis in the ID group were far less than those of the RD group. At week 65, all rats in the RD group developed liver cancer, whereas none did in the ID group. These results suggest that the accumulation of iron, possibly by virtue of synergistic radical formation with copper, plays an essential role in the development of fulminant hepatitis, hepatic fibrosis, and subsequent hepatocarcinogenesis in LEC rats.

  17. Accumulation of polychlorinated dibenzo-p-dioxins and dibenzofurans in liver of control laboratory rats.

    PubMed

    Vanden Heuvel, J P; Clark, G C; Tritscher, A m; Lucier, G W

    1994-10-01

    Polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls belong to a class of compounds, the polyhalogenated aromatic hydrocarbons (PHAHs), which are ubiquitous environmental contaminants. Due to the existence of a common mechanism of action, i.e., binding to the Ah receptor, the activity of members of this class of compounds is generally expressed relative to the prototypical 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as toxic equivalency factors (TEFs). In the present studies we examined the presence of liver of untreated PCDFs in standard laboratory feed and in the liver of untreated rats at three different ages (60, 140, and 200 days) in terms of concentration and in toxic equivalents (TEQs, TEF x concentration). Feed was shown to contain trace amounts of PCDDs and PCDFs and control rat liver was shown to contain several PCDD and PCDF congeners in terms of concentration of congener and concentration of TEQs contributed by that congener. The total concentration of TEQs increased with increasing age in rat liver, going from 20 ppt TEQ at 60 days to 78 ppt TEQ at 200 days of age. This accumulation in dioxin-like activity was due primarily to PCDFs. In particular the congener 2,3,4,7,8-pentachlorodibenzofuran accrued in untreated rat liver accounting for approximately 80% of the total TEQ at 200 days of age. These studies affirm the pervasive presence of PHAHs and suggest prudence in evaluating chronic rat studies in which interference from background levels of PCDDs and PCDFs may be a factor.

  18. Fructose consumption during pregnancy and lactation induces fatty liver and glucose intolerance in rats.

    PubMed

    Zou, Mi; Arentson, Emily J; Teegarden, Dorothy; Koser, Stephanie L; Onyskow, Laurie; Donkin, Shawn S

    2012-08-01

    Nutritional insults during pregnancy and lactation are health risks for mother and offspring. Both fructose (FR) and low-protein (LP) diets are linked to hepatic steatosis and insulin resistance in nonpregnant animals. We hypothesized that dietary FR or LP intake during pregnancy may exacerbate the already compromised glucose homeostasis to induce gestational diabetes and fatty liver. Therefore, we investigated and compared the effects of LP or FR intake on hepatic steatosis and insulin resistance in unmated controls (CTs) and pregnant and lactating rats. Sprague-Dawley rats were fed a CT, or a 63% FR, or an 8% LP diet. Glucose tolerance test at day 17 of the study revealed greater (P < .05) blood glucose at 10 (75.6 mg/dL vs 64.0 ± 4.8 mg/dL) minutes and 20 (72.4 mg/dL vs 58.6 ± 4.0 mg/dL) minutes after glucose dose and greater area under the curve (4302.3 mg∙dL(-1)∙min(-1) vs 3763.4 ± 263.6 mg∙dL(-1)∙min(-1)) for FR-fed dams compared with CT-fed dams. The rats were euthanized at 21 days postpartum. Both the FR- and LP-fed dams had enlarged (P < .05) livers (9.3%, 7.1% body weight vs 4.8% ± 0.2% body weight) and elevated (P < .05) liver triacylglycerol (216.0, 130.0 mg/g vs 19.9 ± 12.6 mg/g liver weight) compared with CT-fed dams. Fructose induced fatty liver and glucose intolerance in pregnant and lactating rats, but not unmated CT rats. The data demonstrate a unique physiological status response to diet resulting in the development of gestational diabetes coupled with hepatic steatosis in FR-fed dams, which is more severe than an LP diet.

  19. Effects of sodium arsenate exposure on liver fatty acid profiles and oxidative stress in rats.

    PubMed

    Kharroubi, Wafa; Dhibi, Madiha; Haouas, Zohra; Chreif, Imed; Neffati, Fadoua; Hammami, Mohamed; Sakly, Rachid

    2014-02-01

    The present study aimed to evaluate the effect of arsenic on liver fatty acids (FA) composition, hepatotoxicity and oxidative status markers in rats. Male rats were randomly devised to six groups (n=10 per group) and exposed to sodium arsenate at a dose of 1 and 10 mg/l for 45 and 90 days. Arsenate exposure is associated with significant changes in the FA composition in liver. A significant increase of saturated fatty acids (SFA) in all treated groups (p<0.01) and trans unsaturated fatty acids (trans UFA) in rats exposed both for short term for 10 mg/l (p<0.05) and long term for 1 and 10 mg/l (p<0.001) was observed. However, the cis UFA were significantly decreased in these groups (p<0.05). A markedly increase of indicator in cell membrane viscosity expressed as SFA/UFA was reported in the treated groups (p<0.001). A significant increase in the level of malondialdehyde by 38.3 % after 90 days of exposure at 10 mg/l was observed. Compared to control rats, significant liver damage was observed at 10 mg/l of arsenate by increasing plasma marker enzymes after 90 days. It is through the histological investigations in hepatic tissues of exposed rats that these damage effects of arsenate were confirmed. The antioxidant perturbations were observed to be more important at groups treated by the high dose (p<0.05). An increase in the level of protein carbonyls was observed in all treated groups (p<0.05). The present study provides evidence for a direct effect of arsenite on FA composition disturbance causing an increase of SFA and TFAs isomers, liver dysfunction and oxidative stress. Therefore, arsenate can lead to hepatic damage and propensity towards liver cancer. PMID:23949113

  20. Antioxidant Effects of Bone Marrow Mesenchymal Stem Cell against Carbon Tetrachloride-Induced Oxidative Damage in Rat Livers

    PubMed Central

    Ayatollahi, M.; Hesami, Z.; Jamshidzadeh, A.; Gramizadeh, B.

    2014-01-01

    Background: Liver fibrosis results from excessive accumulation of extracellular matrix, which affects liver function over time and leads to its failure. In the past, liver transplant was thought to be the only treatment for end-stage liver disease, but due to the shortage of proper donors other medical treatments have been taken into consideration. Objective: To evaluate the therapeutic effects of bone marrow derived mesenchymal stem cells (BM-MSC) in CCl4 damaged rats. Methods: Liver damage in adult male Wistar rats was induced with carbon tetrachloride (CCl4). The rats were divided into normal control group, receiving CCl4, and those receiving CCl4 + marrow derived-MSC. Human BM-MSC was isolated, cultured, and characterized. The rats were injected with xenograft MSCs into the hepatic lobes of the liver. In the eighth week, blood samples were taken from all groups. Histological examination and biochemical analyses were used to compare the morphological and functional liver regeneration among different groups. Measurement of lipid peroxidation and glutathione transferase activity was also performed. Results: Histopathology and biochemical analyses indicated that local injection of human BM-MSCs was effective in treating liver failure in the rat model. Furthermore, oxidative stress was attenuated by increased level of GSH content after MSC transplantation. Conclusion: Evidence of this animal model approach showed that bone marrow-derived MSCs promote an antioxidant response and support the potential of using MSCs transplantation as an effective treatment modality for liver disease. PMID:25426285

  1. Microarray analysis in rat liver slices correctly predicts in vivo hepatotoxicity

    SciTech Connect

    Elferink, M.G.L. Olinga, P.; Draaisma, A.L.; Merema, M.T.; Bauerschmidt, S.; Polman, J.; Schoonen, W.G.; Groothuis, G.M.M.

    2008-06-15

    The microarray technology, developed for the simultaneous analysis of a large number of genes, may be useful for the detection of toxicity in an early stage of the development of new drugs. The effect of different hepatotoxins was analyzed at the gene expression level in the rat liver both in vivo and in vitro. As in vitro model system the precision-cut liver slice model was used, in which all liver cell types are present in their natural architecture. This is important since drug-induced toxicity often is a multi-cellular process involving not only hepatocytes but also other cell types such as Kupffer and stellate cells. As model toxic compounds lipopolysaccharide (LPS, inducing inflammation), paracetamol (necrosis), carbon tetrachloride (CCl{sub 4}, fibrosis and necrosis) and gliotoxin (apoptosis) were used. The aim of this study was to validate the rat liver slice system as in vitro model system for drug-induced toxicity studies. The results of the microarray studies show that the in vitro profiles of gene expression cluster per compound and incubation time, and when analyzed in a commercial gene expression database, can predict the toxicity and pathology observed in vivo. Each toxic compound induces a specific pattern of gene expression changes. In addition, some common genes were up- or down-regulated with all toxic compounds. These data show that the rat liver slice system can be an appropriate tool for the prediction of multi-cellular liver toxicity. The same experiments and analyses are currently performed for the prediction of human specific toxicity using human liver slices.

  2. In vivo quantitation of the rat liver's ability to eliminate endotoxin from portal vein blood

    SciTech Connect

    Yamaguchi, Y.; Yamaguchi, K.; Babb, J.L.; Gans, H.

    1982-12-01

    The in vivo uptake of endotoxin by the liver from portal vein blood was assessed during a single passage through the liver. /sup 51/Cr labeled and unlabeled endotoxin were infused in different amounts into the femoral vein of three groups of lead-sensitized rats: a nonoperated, a sham-operated, and a surgically created reversed Eck fistula (REF) group. Whereas in the former two the infused endotoxin encounters the lung as the first filter organ, the liver performs this function in the latter experimental model. The mortality rates observed in control and sham-operated, lead-sensitized rats were found to correlate closely and reproducibly to the degree of endotoxemia. This assay was then applied to determine the amount of endotoxin eliminated by the liver by establishing, in the REF rat, the amounts of endotoxin that escaped hepatic clearance. The capacity of the liver to eliminate endotoxin from portal vein blood during a single passage increases as the portal vein endotoxin level rises; it approaches a maximum, suggesting that endotoxin's interaction with the Kupffer cells conforms to classical saturation kinetics. A Lineweaver-Burk plot prepared from these data indicates that the maximal in vivo capacity of the liver to remove endotoxin from portal vein blood approximates 1.5 micrograms/gm liver/hr. Data obtained with the use of radiolabeled endotoxin corroborate the information obtained with the bioassay technique. Endotoxin eliminated by the Kupffer cells in these quantities is slowly disintegrated; 4 hr after termination of the endotoxin infusion, less than 4% of the radiolabel is found in the urine and none in the bile. These observations indicate that the Kupffer cell's functional capacity to sequester and detoxify endotoxin is extensive and far exceeds the requirements imposed by physiological and most pathological conditions.

  3. Troxerutin protects the isolated perfused rat liver from a possible lipid peroxidation by coumarin.

    PubMed

    Adam, B S; Pentz, R; Siegers, C P; Strubelt, O; Tegtmeier, M

    2005-01-01

    For more than 40 years coumarin has been successfully used in the therapy of chronic venous insufficiency (CVI). The occurrence of liver injuries is rather rare and happens predominantly when doses are administered which are significantly higher than necessary for therapeutical use. Such effects caused by high coumarin concentrations are reproducible in in vivo experiments in mice or rats and HepG2-cells. In order to characterize the mechanism of liver injuries, the isolated perfused rat liver has been chosen as model. Since liver injuries are quite rare, if coumarin is used in co-medication with troxerutin, a possible protective influence of this flavonoid has been investigated. In concentrations higher than 4 mmol/l, coumarin alone is effective in the isolated perfused rat liver. Then the release of the enzymes alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) increases and there is a measurable reduction of perfusion flow, oxygen consumption and rate of bile secretion. Additionally, the concentrations of hepatic adenosine triphosphate (ATP) and oxidized and total glutathione (GSSG/GSH) decrease. In the livers of fasting animals, coumarin doubles the concentration of hepatic malondialdehyde (MDA). This effect cannot be detected if troxerutin is added. In general, troxerutin reduces the concentration of all coumarin-metabolites in the perfusate and bile and changes the ratio of the main metabolites, coumarin: 3-hydroxycoumarin: 7-hydroxycoumarin. An analysis of the metabolic steps also shows that the amount of coumarin eliminated via faeces does not stem from absorbed coumarin, because the amount of orally applied coumarin detectable in the bile is less than 1%. The study demonstrates that troxerutin has hepatoprotective properties and thus protects the liver from a possible lipid peroxidation caused by coumarin. However, it is necessary to point out that these adverse effects caused by coumarin can be detected only in very high concentrations

  4. Gene expression analyses of the liver in rats treated with oxfendazole.

    PubMed

    Dewa, Yasuaki; Nishimura, Jihei; Muguruma, Masako; Matsumoto, Sayaka; Takahashi, Miwa; Jin, Meilan; Mitsumori, Kunitoshi

    2007-09-01

    The effect of oxfendazole (OX), a benzimidazole anthelmintic, on hepatic gene expression was investigated in the liver of rats as a preliminary study to elucidate the possible mechanism of its non-genotoxic hepatocarcinogenesis. The liver from a male F344/N rat given a diet containing 500 ppm of OX for 3 weeks was examined by global gene expression analysis in comparison with an untreated rat. Microarray analysis revealed that phase I and phase II detoxifying enzymes were up-regulated in an OX-treated rat. In addition to these genes, the expressions of several upregulated genes related to xenobiotic metabolism and oxidative stress [e.g. Cyp1a1; NAD(P)H dehydrogenase, quinone 1 (Nqo1); glutathione peroxidase 2 (Gpx2); glutathione S-transferase Yc2 subunit (Yc2)], were confirmed by real-time reverse transcription polymerase chain reaction (RT-PCR). Furthermore, rats were administered 500 or 1,000 ppm of OX for 9 weeks, and the effect of OX on oxidative stress responses was evaluated by real-time RT-PCR along with conventional toxicological assays, including lipid peroxidation (thiobarbituric acid-reactive substance; TBARS). A longer treatment period and/or a higher dose of OX tended to increase the gene expressions of not only phase I (Cyp1a1 and Cyp1a2) but also phase II (Nqo1, Gpx2, Yc2, and Akr7a3) drug metabolizing enzymes. Toxicological parameters, such as TBARS, serum aspartate aminotransferase (AST), and serum alkaline phosphatase (ALP), showed slight but significant increases after treatment with OX for 9 weeks. These results indicate that OX elicits adaptive responses against oxidative stress in the liver and suggest that the imbalance in redox status might be one of the factors triggering the initial step of OX-induced non-genotoxic carcinogenesis in the liver of rats.

  5. A High Phosphorus Diet Affects Lipid Metabolism in Rat Liver: A DNA Microarray Analysis.

    PubMed

    Chun, Sunwoo; Bamba, Takeshi; Suyama, Tatsuya; Ishijima, Tomoko; Fukusaki, Eiichiro; Abe, Keiko; Nakai, Yuji

    2016-01-01

    A high phosphorus (HP) diet causes disorders of renal function, bone metabolism, and vascular function. We previously demonstrated that DNA microarray analysis is an appropriate method to comprehensively evaluate the effects of a HP diet on kidney dysfunction such as calcification, fibrillization, and inflammation. We reported that type IIb sodium-dependent phosphate transporter is significantly up-regulated in this context. In the present study, we performed DNA microarray analysis to investigate the effects of a HP diet on the liver, which plays a pivotal role in energy metabolism. DNA microarray analysis was performed with total RNA isolated from the livers of rats fed a control diet (containing 0.3% phosphorus) or a HP diet (containing 1.2% phosphorus). Gene Ontology analysis of differentially expressed genes (DEGs) revealed that the HP diet induced down-regulation of genes involved in hepatic amino acid catabolism and lipogenesis, while genes related to fatty acid β-oxidation process were up-regulated. Although genes related to fatty acid biosynthesis were down-regulated in HP diet-fed rats, genes important for the elongation and desaturation reactions of omega-3 and -6 fatty acids were up-regulated. Concentrations of hepatic arachidonic acid and eicosapentaenoic acid were increased in HP diet-fed rats. These essential fatty acids activate peroxisome proliferator-activated receptor alpha (PPARα), a transcription factor for fatty acid β-oxidation. Evaluation of the upstream regulators of DEGs using Ingenuity Pathway Analysis indicated that PPARα was activated in the livers of HP diet-fed rats. Furthermore, the serum concentration of fibroblast growth factor 21, a hormone secreted from the liver that promotes fatty acid utilization in adipose tissue as a PPARα target gene, was higher (p = 0.054) in HP diet-fed rats than in control diet-fed rats. These data suggest that a HP diet enhances energy expenditure through the utilization of free fatty acids

  6. A High Phosphorus Diet Affects Lipid Metabolism in Rat Liver: A DNA Microarray Analysis

    PubMed Central

    Chun, Sunwoo; Bamba, Takeshi; Suyama, Tatsuya; Ishijima, Tomoko; Fukusaki, Eiichiro; Abe, Keiko; Nakai, Yuji

    2016-01-01

    A high phosphorus (HP) diet causes disorders of renal function, bone metabolism, and vascular function. We previously demonstrated that DNA microarray analysis is an appropriate method to comprehensively evaluate the effects of a HP diet on kidney dysfunction such as calcification, fibrillization, and inflammation. We reported that type IIb sodium-dependent phosphate transporter is significantly up-regulated in this context. In the present study, we performed DNA microarray analysis to investigate the effects of a HP diet on the liver, which plays a pivotal role in energy metabolism. DNA microarray analysis was performed with total RNA isolated from the livers of rats fed a control diet (containing 0.3% phosphorus) or a HP diet (containing 1.2% phosphorus). Gene Ontology analysis of differentially expressed genes (DEGs) revealed that the HP diet induced down-regulation of genes involved in hepatic amino acid catabolism and lipogenesis, while genes related to fatty acid β-oxidation process were up-regulated. Although genes related to fatty acid biosynthesis were down-regulated in HP diet-fed rats, genes important for the elongation and desaturation reactions of omega-3 and -6 fatty acids were up-regulated. Concentrations of hepatic arachidonic acid and eicosapentaenoic acid were increased in HP diet-fed rats. These essential fatty acids activate peroxisome proliferator-activated receptor alpha (PPARα), a transcription factor for fatty acid β-oxidation. Evaluation of the upstream regulators of DEGs using Ingenuity Pathway Analysis indicated that PPARα was activated in the livers of HP diet-fed rats. Furthermore, the serum concentration of fibroblast growth factor 21, a hormone secreted from the liver that promotes fatty acid utilization in adipose tissue as a PPARα target gene, was higher (p = 0.054) in HP diet-fed rats than in control diet-fed rats. These data suggest that a HP diet enhances energy expenditure through the utilization of free fatty acids

  7. Effects of glutamine on oxidative stress and nuclear factor-κB expression in the livers of rats with nonalcoholic fatty liver disease

    PubMed Central

    LIN, ZHIHUI; CAI, FANGFANG; LIN, NING; YE, JINLI; ZHENG, QIQI; DING, GUISHENG

    2014-01-01

    The aim of this study was to investigate the effects of glutamine on the histomorphology of the liver, oxidative stress and nuclear factor-κB (NF-κB) expression in the development of nonalcoholic fatty liver disease (NAFLD). NAFLD was induced in rats by a high-fat diet, and rats in the treatment group were subjected to oral administration of glutamine (1 g/kg/day). Rats from the treatment, model and normal control groups were assessed after 8 and 12 weeks (n=6 per group at each time-point). The levels of glutathione (GSH), malondialdehyde (MDA) and tumor necrosis factor-α (TNF-α) in the liver, and the liver histopathology and NF-κB protein 65 (p65) expression in the liver were assessed. Compared with the control group under the same experimental period, the MDA and TNF-α levels in the liver, the hepatic steatosis and the hepatic expression of NF-κB p65 were significantly higher in the model and the treatment groups (P<0.05), while the GSH levels in the liver were significantly lower (P<0.05). These indices improved significantly in the treatment group compared with the model group (P<0.05). In conclusion, glutamine reduces the degree of oxidative stress in the liver, inhibits NF-κB p65 expression and improves hepatic steatosis. Glutamine has a certain protective effect in NAFLD. PMID:24396406

  8. Liver volume, as assessed by four ultrasonic crystals arranged to form a tetrahedron, decreases during anaphylactic shock in anesthetized rats.

    PubMed

    Takano, Hiromichi; Shibamoto, Toshishige; Zhang, Wei; Kurata, Yasutaka

    2010-12-01

    We determined the hepatic volume change in anaphylactic hypotension by using four ultrasonic crystals in anesthetized rats. The hepatic volume was measured with four ultrasonic crystals arranged to form a tetrahedron on the liver surface. Before in vivo experiments, using isolated perfused rat liver preparations, we compared the measured liver volume changes with the whole-liver weight changes during hepatic blood flow rate changes and venoconstriction induced by norepinephrine. The measured relative change of the tetrahedron volume (V[utc]; percentage changes of the initial volume) was closely correlated with the liver weight change (W; percentage changes of the initial liver weight): V(utc) = 0.85W - 4.11 (r² = 0.67). Then, we measured the liver weight and the tetrahedron volume during hepatic anaphylaxis in isolated perfused liver excised from the rats sensitized with ovalbumin. An injection of the antigen into the perfusate caused anaphylactic venoconstriction, liver weight loss (1.1 ± 0.3 g; 9% ± 1%), and the tetrahedron volume reduction (12% ± 4%). Finally, we measured the liver volume change during anaphylactic hypotension in anesthetized ovalbumin-sensitized rats. When the antigen was i.v. injected into anesthetized rats, along with systemic hypotension and hepatic venoconstriction, the liver tetrahedron volume decreased by 6% ± 2% from baseline. In conclusion, we established a method to measure the hepatic volume by using four ultrasonic crystals forming a tetrahedron. Using this ultrasonic crystal method, we demonstrated that liver volume decreases during anaphylactic hypotension in anesthetized rats.

  9. New physiologically-relevant liver tissue model based on hierarchically cocultured primary rat hepatocytes with liver endothelial cells.

    PubMed

    Xiao, Wenjin; Perry, Guillaume; Komori, Kikuo; Sakai, Yasuyuki

    2015-11-01

    To develop an in vitro liver tissue equivalent, hepatocytes should be cocultured with liver non-parenchymal cells to mimic the in vivo physiological microenvironments. In this work, we describe a physiologically-relevant liver tissue model by hierarchically organizing layers of primary rat hepatocytes and human liver sinusoidal endothelial cells (TMNK-1) on an oxygen-permeable polydimethylsiloxane (PDMS) membrane, which facilitates direct oxygenation by diffusion through the membrane. This in vivo-mimicking hierarchical coculture was obtained by simply proceeding the overlay of TMNK-1 cells on the hepatocyte layer re-formed on the collagen immobilized PDMS membranes. The comparison of hepatic functionalities was achieved between coculture and sandwich culture with Matrigel, in the presence and absence of direct oxygenation. A complete double-layered structure of functional liver cells with vertical contact between hepatocytes and TMNK-1 was successfully constructed in the coculture with direct oxygen supply and was well-maintained for 14 days. The hepatocytes in this hierarchical culture exhibited improved survival, functional bile canaliculi formation, cellular level polarization and maintenance of metabolic activities including Cyp1A1/2 activity and albumin production. By contrast, the two cell populations formed discontinuous monolayers on the same surfaces in the non-oxygen-permeable cultures. These results demonstrate that (i) the direct oxygenation through the PDMS membranes enables very simple formation of a hierarchical structure consisting of a hepatocyte layer and a layer of TMNK-1 and (ii) we may include other non-parenchymal cells in this format easily, which can be widely applicable to other epithelial organs.

  10. The effect of phytosterol protects rats against 4-nitrophenol-induced liver damage.

    PubMed

    Chen, Jiaqin; Song, Meiyan; Li, Yansen; Zhang, Yonghui; Taya, Kazuyoshi; Li, ChunMei

    2016-01-01

    We investigated the effect of phytosterol (PS) in regard to liver damage induced by 4-nitrophenol (PNP). Twenty rats were randomly divided into four groups (Control, PS, PNP, and PNP+PS). The PS and PNP+PS groups were pretreated with PS for one week. The PNP and PNP+PS groups were injected subcutaneously with PNP for 28 days. The control group received a basal diet and was injected with vehicle alone. Treatment with PS prevented the elevation of the total bilirubin levels, as well as an increase in serum alkaline transaminase and aspartate transaminase, which are typically caused by PNP-induced liver damage. Histopathologically showed that liver damage was significantly mitigated by PS treatment. However, there was no significant change in antioxidant enzyme activities, and the Nrf2-antioxidant system was not activated after treatment with PS. These results suggest that PS could mitigate liver damage induced by PNP, but does not enhance antioxidant capacity. PMID:26748050

  11. Quantitative Estimation of the Amount of Fibrosis in the Rat Liver Using Fractal Dimension of the Shape of Power Spectrum

    NASA Astrophysics Data System (ADS)

    Kikuchi, Tsuneo; Nakazawa, Toshihiro; Furukawa, Tetsuo; Higuchi, Toshiyuki; Maruyama, Yukio; Sato, Sojun

    1995-05-01

    This paper describes the quantitative measurement of the amount of fibrosis in the rat liver using the fractal dimension of the shape of power spectrum. The shape of the power spectrum of the scattered echo from biotissues is strongly affected by its internal structure. The fractal dimension, which is one of the important parameters of the fractal theory, is useful to express the complexity of shape of figures such as the power spectrum. From in vitro experiments using rat liver, it was found that this method can be used to quantitatively measure the amount of fibrosis in the liver, and has the possibility for use in the diagnosis of human liver cirrhosis.

  12. Influence of nandrolone decanoate administration on serum lipids and liver enzymes in rats

    PubMed Central

    Samieinasab, Mohammad Reza; Shahraki, Mohammad Reza; Samieinasab, Fatemah; Najafi, Somayeh

    2015-01-01

    BACKGROUND Anabolic-androgenic steroids have been associated with several side effects range. This experimental study was conducted to evaluate the effects of nandrolone decanoate (ND, an anabolic steroid) on lipid profile and liver enzymes in rats in Iran. METHODS Forty adult male and female of Wistar strain rats were randomly assigned to four groups of 10 animals each: male control, female control, ND-male treated (15 mg/kg b.w./day), and ND-female treated (15 mg/kg b.w./day). Serum concentrations of total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) were measured in all studied groups. RESULTS Treating rats with ND (case group) resulted in a significant elevation of TC (69.4 ± 8.7), TG (101.6 ± 32.9) and ALT (72.2 ± 13.8) and significant reduction of LDL (6.4 ± 2.6) and AST (138.7 ± 19.4) as compared to control group in female rats. ND supplementation (case group) significantly increased TC (64.4 ± 6.2), AST (255.0 ± 32.0), and ALT (84.3 ± 3.8) in comparison with the control group in male rats. CONCLUSION Overall, our result indicated that the ND use can cause a negative effect on lipid profile and liver enzyme in rats. PMID:26478734

  13. Effects of human low and high density lipoproteins on the binding of rat intermediate density lipoproteins to rat liver membranes

    SciTech Connect

    Brissette, L.; Nol, S.P.

    1986-05-25

    Upon incubation with rat liver membranes, radioiodinated rat intermediate density lipoproteins (IDL) interacted with at least two binding sites having a low and a high affinity as demonstrated by the curvilinear Scatchard plots obtained from the specific binding data. The purpose of our work was to identify the nature of these binding sites. Human low density lipoproteins (LDL), contain apolipoprotein B only, and human high density lipoproteins (HDL3), containing neither apolipoprotein B nor E, were both capable of decreasing the specific binding of rat /sup 125/I-IDL. The Scatchard analysis clearly revealed that only the low affinity component was affected by the addition of these human lipoproteins. In fact, the low affinity binding component gradually decreased as the amount of human LDL or HDL3 increased in the binding assay. At a 200-fold excess of human LDL or HDL3, the low affinity binding was totally masked, and the Scatchard plot of the specific /sup 125/I-IDL binding became linear. Only the high affinity binding component was left, enabling a precise measurement of its binding parameters. In a series of competitive displacement experiments in which the binding assay contained a 200-fold excess of human LDL or HDL3, only unlabeled rat IDL effectively displaced the binding of rat /sup 125/I-IDL. We conclude that the low affinity binding of rat IDL to rat liver membranes is due to weak interactions with unspecified lipoprotein binding sites. The camouflage of these sites by human lipoproteins makes possible the study of IDL binding to the high affinity component which likely represents the combined effect of IDL binding to both the remnant and the LDL receptors.

  14. Gene expression changes induced by the tumorigenic pyrrolizidine alkaloid riddelliine in liver of Big Blue rats

    PubMed Central

    Mei, Nan; Guo, Lei; Liu, Ruqing; Fuscoe, James C; Chen, Tao

    2007-01-01

    Background Pyrrolizidine alkaloids (PAs) are probably the most common plant constituents that poison livestock, wildlife, and humans worldwide. Riddelliine is isolated from plants grown in the western United States and is a prototype of genotoxic PAs. Riddelliine was used to investigate the genotoxic effects of PAs via analysis of gene expression in the target tissue of rats in this study. Previously we observed that the mutant frequency in the liver of rats gavaged with riddelliine was 3-fold higher than that in the control group. Molecular analysis of the mutants indicated that there was a statistically significant difference between the mutational spectra from riddelliine-treated and control rats. Results Riddelliine-induced gene expression profiles in livers of Big Blue transgenic rats were determined. The female rats were gavaged with riddelliine at a dose of 1 mg/kg body weight 5 days a week for 12 weeks. Rat whole genome microarray was used to perform genome-wide gene expression studies. When a cutoff value of a two-fold change and a P-value less than 0.01 were used as gene selection criteria, 919 genes were identified as differentially expressed in riddelliine-treated rats compared to the control animals. By analysis with the Ingenuity Pathway Analysis Network, we found that these significantly changed genes were mainly involved in cancer, cell death, tissue development, cellular movement, tissue morphology, cell-to-cell signaling and interaction, and cellular growth and proliferation. We further analyzed the genes involved in metabolism, injury of endothelial cells, liver abnormalities, and cancer development in detail. Conclusion The alterations in gene expression were directly related to the pathological outcomes reported previously. These results provided further insight into the mechanisms involved in toxicity and carcinogenesis after exposure to riddelliine, and permitted us to investigate the interaction of gene products inside the signaling networks

  15. Folate supplementation increases genomic DNA methylation in the liver of elder rats.

    PubMed

    Choi, Sang-Woon; Friso, Simonetta; Keyes, Mary K; Mason, Joel B

    2005-01-01

    The availability of folate is implicated as a determinant of DNA methylation, a functionally important feature of DNA. Nevertheless, when this phenomenon has been examined in the rodent model, the effect has not always been observed. Several reasons have been postulated for the inconsistency between studies: the rodent is less dependent on folate as a methyl source than man; juvenile animals, which most studies use, are more resistant to folate depletion than old animals; methods to measure genomic DNA methylation might not be sensitive enough to detect differences. We therefore examined the relationship between folate and genomic DNA methylation in an elder rat model with a newly developed method that can measure genomic DNA methylation sensitively and precisely. Thirty-nine 1-year-old rats were divided into three groups and fed a diet containing 0, 4.5 or 18 mumol folate/kg (folate-deplete, -replete and -supplemented groups, respectively). Rats were killed at 8 and 20 weeks. At both time points, mean liver folate concentrations increased incrementally between the folate-deplete, -replete and -supplemented rats (P for trend <0.001) and by 20 weeks hepatic DNA methylation also increased incrementally between the folate-deplete, -replete and -supplemented rats (P for trend=0.025). At both time points folate-supplemented rats had significantly increased levels of DNA methylation compared with folate-deplete rats (P<0.05). There was a strong correlation between hepatic folate concentration and genomic DNA methylation in the liver (r 0.48, P=0.004). In the liver of this animal model, dietary folate over a wide range of intakes modulates genomic DNA methylation.

  16. Differential effects of estrogen/androgen on the prevention of nonalcoholic fatty liver disease in the male rat[S

    PubMed Central

    Zhang, Hua; Liu, Yuanwu; Wang, Li; Li, Zhen; Zhang, Hongwen; Wu, Jihua; Rahman, Nafis; Guo, Yangdong; Li, Defa; Li, Ning; Huhtaniemi, Ilpo; Tsang, Suk Ying; Gao, George F.; Li, Xiangdong

    2013-01-01

    It is important to clarify the distinct contributions of estrogen/estrogen receptor (ER) and androgen/androgen receptor (AR) signaling and their reciprocal effects on the regulation of hepatic lipid homeostasis. We studied the molecular mechanisms underlying the preventive effects of estradiol (E2), dihydrotestosterone (DHT), or E2+DHT on high-fat diet-induced nonalcoholic fatty liver disease (NAFLD) in an orchidectomized Sprague-Dawley (SD) rat model. E2 is shown to be associated with decreased fatty acid synthesis in hepatic zone 3-specific manner by increasing the phosphorylation of acetyl coenzyme-A carboxylase via an ERα-mediated pathway. DHT is shown to be associated with decreased lipid accumulation and cholesterol synthesis in a hepatic zone 1-specific manner by increasing expression of carnitine palmitotyltransferase1 and phosphorylation of 3-hydroxy-3-methyl-glutaryl-CoA reductase via an AR-mediated pathway. E2+DHT showed an additive positive effect and normalized all three impaired zones of the liver. Gene expression changes in human severe liver steatosis were similar to those of experimental rat NAFLD. Steroids reversed the histopathological NAFLD changes, likely by decreasing fatty acid and cholesterol synthesis and increasing β-oxidation. The diverse steroid effects (ER/AR) on NAFLD prevention in male rats indicate the potential applicability of ER/AR modulators for NAFLD treatment. PMID:23175777

  17. Simple Machine Perfusion Significantly Enhances Hepatocyte Yields of Ischemic and Fresh Rat Livers

    PubMed Central

    Izamis, Maria-Louisa; Calhoun, Candice; Uygun, Basak E.; Guzzardi, Maria Angela; Price, Gavrielle; Luitje, Martha; Saeidi, Nima; Yarmush, Martin L.; Uygun, Korkut

    2013-01-01

    The scarcity of viable hepatocytes is a significant bottleneck in cell transplantation, drug discovery, toxicology, tissue engineering, and bioartificial assist devices, where trillions of high-functioning hepatocytes are needed annually. We took the novel approach of using machine perfusion to maximize cell recovery, specifically from uncontrolled cardiac death donors, the largest source of disqualified donor organs. In a rat model, we developed a simple 3-h room temperature (20 ± 2°C) machine perfusion protocol to treat nonpremedicated livers exposed to 1 h of warm (34°C) ischemia. Treated ischemic livers were compared to fresh, fresh-treated, and untreated ischemic livers using viable hepatocyte yields and in vitro performance as quantitative endpoints. Perfusion treatment resulted in both a 25-fold increase in viable hepatocytes from ischemic livers and a 40% increase from fresh livers. While cell morphology and function in suspension and plate cultures of untreated warm ischemic cells was significantly impaired, treated warm ischemic cells were indistinguishable from fresh hepatocytes. Furthermore, a strong linear correlation between tissue ATP and cell yield enabled accurate evaluation of the extent of perfusion recovery. Maximal recovery of warm ischemic liver ATP content appears to be correlated with optimal flow through the microvasculature. These data demonstrate that the inclusion of a simple perfusion-preconditioning step can significantly increase the efficiency of functional hepatocyte yields and the number of donor livers that can be gainfully utilized. PMID:25431743

  18. Determinants of hepatic function in liver cirrhosis in the rat. Multivariate analysis.

    PubMed Central

    Reichen, J; Egger, B; Ohara, N; Zeltner, T B; Zysset, T; Zimmermann, A

    1988-01-01

    We investigated the determinants of hepatic clearance functions in a rat model of liver cirrhosis induced by phenobarbital/CCl4. Aminopyrine N-demethylation (ABT), galactose elimination (GBT), and serum bile acids (SBA) were determined in vivo. The livers were then characterized hemodynamically: intrahepatic shunting (IHS) was determined by microspheres and sinusoidal capillarization by measuring the extravascular albumin space (EVA) by a multiple indicator dilution technique. The intrinsic clearance was determined by assaying the activity of the rate-limiting enzymes in vitro. Hepatocellular volume (HCV) was measured by morphometry. ABT and SBA, but not GBT, differentiated cirrhotic from normal liver. IHS ranged from normal to 10%; all cirrhotic livers showed evidence of sinusoidal capillarization (reduced EVA). The cirrhotic livers showed a bimodal distribution of HCV, HCV being decreased in 50% of the cirrhotic livers. Multivariate analysis showed EVA and portal flow to be the main determinants of microsomal (ABT) and cytosolic (GBT) clearance function; SBA, by contrast, were determined solely by IHS. We conclude that sinusoidal capillarization is the main determinant of hepatic clearance, while serum bile acids reflect intrahepatic shunting. These findings emphasize the importance of alterations of hepatic nutritional flow to explain reduced clearance function in cirrhosis of the liver. PMID:3198765

  19. Kava feeding in rats does not cause liver injury nor enhance galactosamine-induced hepatitis.

    PubMed

    DiSilvestro, Robert A; Zhang, Wenyi; DiSilvestro, David J

    2007-07-01

    Kava, like a number of herbals, has been associated with causing liver damage based on limited evidence. In contrast, the present study found that in rats, 3 mo feedings of two types of kava extracts (an acetone extract and an ethanol extract of the Samoan kava cultivar Ava Laau) at three different doses (31.25, 62.5 and 133 mg/kg diet) produced no liver injury based on serum markers of liver damage (sorbitol dehydrogenase activities, bile acid concentrations, and beta-glucuronidase activities) and serum lipid peroxide readings. In fact, for some measurements and some kava doses, the injury marker readings were below control values. Moreover, for these same parameters, kava feeding did not enhance the effects of the hepatotoxin galacatosamine (500 mg/kg ip); some kava doses even showed modest protection against liver injury. Liver histology analysis showed no signs of kava causing or enhancing liver injury. Thus, this study does not support the concept that kava produces or aggravates liver injury.

  20. Ex vivo expansion of circulating CD34(+) cells enhances the regenerative effect on rat liver cirrhosis.

    PubMed

    Nakamura, Toru; Koga, Hironori; Iwamoto, Hideki; Tsutsumi, Victor; Imamura, Yasuko; Naitou, Masako; Masuda, Atsutaka; Ikezono, Yu; Abe, Mitsuhiko; Wada, Fumitaka; Sakaue, Takahiko; Ueno, Takato; Ii, Masaaki; Alev, Cantas; Kawamoto, Atsuhiko; Asahara, Takayuki; Torimura, Takuji

    2016-01-01

    Ex vivo expansion of autologous cells is indispensable for cell transplantation therapy of patients with liver cirrhosis. The aim of this study was to investigate the efficacy of human ex vivo-expanded CD34(+) cells for treatment of cirrhotic rat liver. Recipient rats were intraperitoneally injected with CCl4 twice weekly for 3 weeks before administration of CD34(+) cells. CCl4 was then re-administered twice weekly for 3 more weeks, and the rats were sacrificed. Saline, nonexpanded or expanded CD34(+) cells were injected via the spleen. After 7 days, CD34(+) cells were effectively expanded in a serum-free culture medium. Expanded CD34(+) cells were also increasingly positive for cell surface markers of VE-cadherin, VEGF receptor-2, and Tie-2. The expression of proangiogenic growth factors and adhesion molecules in expanded CD34(+) cells increased compared with nonexpanded CD34(+) cells. Expanded CD34(+) cell transplantation reduced liver fibrosis, with a decrease of αSMA(+) cells. Assessments of hepatocyte and sinusoidal endothelial cell proliferative activity indicated the superior potency of expanded CD34(+) cells over non-expanded CD34(+) cells. The inhibition of integrin αvβ3 and αvβ5 disturbed the engraftment of transplanted CD34(+) cells and aggravated liver fibrosis. These findings suggest that expanded CD34(+) cells enhanced the preventive efficacy of cell transplantation in a cirrhotic model. PMID:27162932

  1. Effect of Pomegranate Hull Extract on Liver Neoplastic Changes in Rats: More than an Antioxidant.

    PubMed

    El-Ashmawy, Nahla E; Khedr, Eman G; El-Bahrawy, Hoda A; Abd El-Fattah, Eslam E

    2016-01-01

    Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer-related mortality worldwide. The current work was designed to elucidate the molecular mechanisms underlying the antitumorigenic effect of pomegranate hull extract (PHE) in livers of rats exposed to the hepatocarcinogen diethyl nitrosamine (DENA) with emphasis on oxidative stress, proliferation, and apoptosis. Male albino rats were divided into three groups: normal control, DENA group, and PHE group. PHE was given to rats orally 3 times weekly for 10 wk, 4 wk before and 6 wk after DENA (200 mg/kg, single i.p. dose). The results indicated a prophylactic effect of PHE against neoplastic changes in the liver, which was evidenced by the decrease of tumor size, liver index, and the anti-apoptotic protein Bcl-2; and the increase of glutathione. PHE group also showed decreased expression of liver cyclin D1 and β-catenin genes compared with DENA group. It is proved that PHE has antitumorigenic effect and could be a candidate for anticancer drugs. PMID:27383944

  2. Effect of sweetener and flavoring agent on oxidative indices, liver and kidney function levels in rats.

    PubMed

    Amin, Kamal A; Al-muzafar, Hessa M; Abd Elsttar, Adel H

    2016-01-01

    Food additives while attract consumers, improve quality, control weight and replace sugar, may affect seriously children and adults health. Here, we investigated the adverse effects of saccharin and methylsalicyltaes as sweetener and flavoring agent on lipid profile, blood glucose, renal, hepatic function and oxidative stress/antioxidants (lipid peroxidation, catalase and reduced glutathione in liver tissues). Saccharin and methylsalicylate were administered orally in young male albino rats at low and high dose for 30 days. Rats were divided into 5 groups, 1st control group, 2nd and 3rd (low and high saccharin-treated groups) and 4th and 5th (low and high methylsalicylate-treated group). Serum total cholesterol, triglyceride, glucose levels and body weight gain were found decreased in saccharin high dose group compared to control. Rats consumed high dose of saccharin showed a significant decrease in serum triglycerides, cholesterol and LDL levels. Low and high doses of saccharin exhibited a significant increase in liver function marker of ALT, AST, ALP activity, total proteins and albumin levels and renal function test (urea and creatinine levels) in comparison with control group. Further, saccharin at high dose induced significant decrease in liver GSH levels, catalase and SOD activity and increase in hepatic MDA level. Overall saccharin harmfully altered biochemical markers in liver and kidney at higher as well as lower doses. Whereas, methyl salicylates did not pose a risk for renal function and hepatic oxidative markers. PMID:26891553

  3. Liver mitochondrial membrane crosslinking and destruction in a rat model of Wilson disease.

    PubMed

    Zischka, Hans; Lichtmannegger, Josef; Schmitt, Sabine; Jägemann, Nora; Schulz, Sabine; Wartini, Daniela; Jennen, Luise; Rust, Christian; Larochette, Nathanael; Galluzzi, Lorenzo; Chajes, Veronique; Bandow, Nathan; Gilles, Valérie S; DiSpirito, Alan A; Esposito, Irene; Goettlicher, Martin; Summer, Karl H; Kroemer, Guido

    2011-04-01

    Wilson disease (WD) is a rare hereditary condition that is caused by a genetic defect in the copper-transporting ATPase ATP7B that results in hepatic copper accumulation and lethal liver failure. The present study focuses on the structural mitochondrial alterations that precede clinical symptoms in the livers of rats lacking Atp7b, an animal model for WD. Liver mitochondria from these Atp7b–/– rats contained enlarged cristae and widened intermembrane spaces, which coincided with a massive mitochondrial accumulation of copper. These changes, however, preceded detectable deficits in oxidative phosphorylation and biochemical signs of oxidative damage, suggesting that the ultrastructural modifications were not the result of oxidative stress imposed by copper- dependent Fenton chemistry. In a cell-free system containing a reducing dithiol agent, isolated mitochondria exposed to copper underwent modifications that were closely related to those observed in vivo. In this cell-free system, copper induced thiol modifications of three abundant mitochondrial membrane proteins, and this correlated with reversible intramitochondrial membrane crosslinking, which was also observed in liver mitochondria from Atp7b–/– rats. In vivo, copper-chelating agents reversed mitochondrial accumulation of copper, as well as signs of intra-mitochondrial membrane crosslinking, thereby preserving the functional and structural integrity of mitochondria. Together, these findings suggest that the mitochondrion constitutes a pivotal target of copper in WD. PMID:21364284

  4. Liver mitochondrial membrane crosslinking and destruction in a rat model of Wilson disease.

    PubMed

    Zischka, Hans; Lichtmannegger, Josef; Schmitt, Sabine; Jägemann, Nora; Schulz, Sabine; Wartini, Daniela; Jennen, Luise; Rust, Christian; Larochette, Nathanael; Galluzzi, Lorenzo; Chajes, Veronique; Bandow, Nathan; Gilles, Valérie S; DiSpirito, Alan A; Esposito, Irene; Goettlicher, Martin; Summer, Karl H; Kroemer, Guido

    2011-04-01

    Wilson disease (WD) is a rare hereditary condition that is caused by a genetic defect in the copper-transporting ATPase ATP7B that results in hepatic copper accumulation and lethal liver failure. The present study focuses on the structural mitochondrial alterations that precede clinical symptoms in the livers of rats lacking Atp7b, an animal model for WD. Liver mitochondria from these Atp7b–/– rats contained enlarged cristae and widened intermembrane spaces, which coincided with a massive mitochondrial accumulation of copper. These changes, however, preceded detectable deficits in oxidative phosphorylation and biochemical signs of oxidative damage, suggesting that the ultrastructural modifications were not the result of oxidative stress imposed by copper- dependent Fenton chemistry. In a cell-free system containing a reducing dithiol agent, isolated mitochondria exposed to copper underwent modifications that were closely related to those observed in vivo. In this cell-free system, copper induced thiol modifications of three abundant mitochondrial membrane proteins, and this correlated with reversible intramitochondrial membrane crosslinking, which was also observed in liver mitochondria from Atp7b–/– rats. In vivo, copper-chelating agents reversed mitochondrial accumulation of copper, as well as signs of intra-mitochondrial membrane crosslinking, thereby preserving the functional and structural integrity of mitochondria. Together, these findings suggest that the mitochondrion constitutes a pivotal target of copper in WD.

  5. Grape Juice Concentrate Protects Rat Liver Against Cadmium Intoxication: Histopathology, Cytochrome C and Metalloproteinases Expression.

    PubMed

    de Moura, C F G; Ribeiro, F A P; Handan, B A; Aguiar, O; Oshima, C T F; Ribeiro, D A

    2016-07-01

    The aim of this study was to investigate if grape juice concentrate is able to protect rat liver against cadmium toxicity. For this purpose, histopathological analysis, cytochrome C expression and immunoexpresssion of metalloproteinases (MMP) 2 and 9 were investigated. A total of 15 Wistar rats weighing 250 g on the average, and 8 weeks age were distributed into 3 groups (n=5), as follows: Control group (non-treated group, CTRL); Cadmium group (Cd) and grape juice concentrate group (Cd+GJ). Histopathological analysis revealed that liver from animals treated with grape juice concentrate improved tissue degeneration induced by cadmium intoxication. Animals intoxicated with cadmium and treated with grape juice concentrate showed higher cytochrome C gene expression in liver cells. No significant statistically differences (p>0.05) were found to MMP 2 and 9 immunoexpression between groups. Taken together, our results demonstrate that grape juice concentrate is able to prevent tissue degeneration in rat liver as a result of increasing apoptosis. PMID:27056637

  6. Propofol Attenuates Toxic Oxidative Stress by CCl4 in Liver Mitochondria and Blood in Rat

    PubMed Central

    Ranjbar, Akram; Sharifzadeh, Mohammad; Karimi, Jamshid; Tavilani, Heidar; Baeeri, Maryam; Heidary shayesteh, Tavakol; Abdollahi, Mohammad

    2014-01-01

    Anti-oxidant effects of propofol (2, 6-diisopropylphenol) were evaluated agains carbon tetrachloridet CCl4 -induced oxidative stress in rat liver. 30 male rats were equally divided in to 6 groups (5 rats each). Group I (control), while Group II was given CCl4 (3 mL /Kg/day, IP). Animals of Groups III received only propofol (10 mg/Kg/day, IP). Group IV was given propofol+ CCl4. Group V was administered vitamin E (alpha-tocopherol acetate 15 mg/Kg/day, SC) .Animals of Group VII received alpha-tocopherol acetate + CCl4 once daily for two weeks. After treatment, blood and liver mitochondria were isolated. Anti-oxidant enzymes activity such as glutathione peroxidase (GPx), superoxide dismutase (SOD) and oxidative stress marker such as reduced glutathione (GSH) and lipid peroxidation (LPO) concentration were measured. Oxidative stress induced with CCl4 in liver mitochondria was evident by a significant increase in enzymatic activities of GPx, SOD, and LPO and decreased of GSH and vailability of mitochondria. Propofol and vitamin E restored CCl4-induced changes in GSH, GPx, SOD and LPO in blood and liver mitochondria. CCl4 decreased viability of mitochondria that was recovered by propofol and vitamin E. It is concluded that oxidative damage is the mechanism of toxicity of CCl4 in the mitochondria that can be recovered by propofol comparable to vitamin E. PMID:24734078

  7. Ex vivo expansion of circulating CD34+ cells enhances the regenerative effect on rat liver cirrhosis

    PubMed Central

    Nakamura, Toru; Koga, Hironori; Iwamoto, Hideki; Tsutsumi, Victor; Imamura, Yasuko; Naitou, Masako; Masuda, Atsutaka; Ikezono, Yu; Abe, Mitsuhiko; Wada, Fumitaka; Sakaue, Takahiko; Ueno, Takato; Ii, Masaaki; Alev, Cantas; Kawamoto, Atsuhiko; Asahara, Takayuki; Torimura, Takuji

    2016-01-01

    Ex vivo expansion of autologous cells is indispensable for cell transplantation therapy of patients with liver cirrhosis. The aim of this study was to investigate the efficacy of human ex vivo-expanded CD34+ cells for treatment of cirrhotic rat liver. Recipient rats were intraperitoneally injected with CCl4 twice weekly for 3 weeks before administration of CD34+ cells. CCl4 was then re-administered twice weekly for 3 more weeks, and the rats were sacrificed. Saline, nonexpanded or expanded CD34+ cells were injected via the spleen. After 7 days, CD34+ cells were effectively expanded in a serum-free culture medium. Expanded CD34+ cells were also increasingly positive for cell surface markers of VE-cadherin, VEGF receptor-2, and Tie-2. The expression of proangiogenic growth factors and adhesion molecules in expanded CD34+ cells increased compared with nonexpanded CD34+ cells. Expanded CD34+ cell transplantation reduced liver fibrosis, with a decrease of αSMA+ cells. Assessments of hepatocyte and sinusoidal endothelial cell proliferative activity indicated the superior potency of expanded CD34+ cells over non-expanded CD34+ cells. The inhibition of integrin αvβ3 and αvβ5 disturbed the engraftment of transplanted CD34+ cells and aggravated liver fibrosis. These findings suggest that expanded CD34+ cells enhanced the preventive efficacy of cell transplantation in a cirrhotic model. PMID:27162932

  8. Insulin resistance in uremia: Insulin receptor kinase activity in liver and muscle from chronic uremic rats

    SciTech Connect

    Cecchin, F.; Ittoop, O.; Sinha, M.K.; Caro, J.F. )

    1988-04-01

    The authors have studied the structure and function of the partially purified insulin receptors from liver and skeletal muscle in a rat model of severe chronic uremia. {sup 125}I-insulin binding was higher in the liver from uremic rats when compared with ad libitum- and pair-fed controls. Furthermore, the ability of insulin to stimulate the autophosphorylation of the {beta}-subunit and insulin receptor kinase activity using Glu{sup 80}, Tyr{sup 20} as exogenous phosphoacceptor was increased in the liver of the uremic animals. The structural characteristics of the receptors, as determined by electrophoretic mobilities of affinity labeled {alpha}-subunit and the phosphorylated {beta}-subunit, were normal in uremia. {sup 125}I-insulin binding and insulin receptor kinase activity were similar in the skeletal muscle from uremic and pair- and ad libitum-fed animals. Thus the data are supportive of the hypothesis that in liver and muscle of chronic uremic rats, insulin resistance is due to a defect(s) distal to the insulin receptor kinase.

  9. Effect of Alocasia indica Tuber Extract on Reducing Hepatotoxicity and Liver Apoptosis in Alcohol Intoxicated Rats

    PubMed Central

    Bhattacharya, Koushik; Mukherjee, Soumya

    2014-01-01

    The possible protective role of ethanolic extract of A. indica tuber (EEAIT) in hepatotoxicity and apoptosis of liver caused by alcohol in rats was investigated. Treatment of rats with alcohol (3 g ethanol per kg body weight per day for 15 days intraperitoneally) produced marked elevation of liver biomarkers such as serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transpeptidase (γ-GT), and total bilirubin levels which were reduced by EEAIT in a dose-dependent manner. Furthermore, EEAIT improved antioxidant status (MDA, NO, and GSH) and preserved hepatic cell architecture. Simultaneous supplementation with EEAIT significantly restored hepatic catalase (CAT) and superoxide dismutase (SOD) activity levels towards normal. The studies with biochemical markers were strongly supported by the histopathological evaluation of the liver tissue. EEAIT also attenuated apoptosis and necrosis features of liver cell found in immunohistochemical evaluation. HPLC analysis of the extract showed the presence of three major peaks of which peak 2 (RT: 33.33 min) contains the highest area (%) and UV spectrum analysis identified it as flavonoids. It is therefore suggested that EEAIT can provide a definite protective effect against chronic hepatic injury caused by alcohol in rats, which may mainly be associated with its antioxidative effect. PMID:24977149

  10. Evaluation of 2-year-old intrasplenic fetal liver tissue transplants in rats.

    PubMed

    Lupp, Amelie; Danz, Manfred; Müller, Dieter

    2003-01-01

    Liver cell transplantation into host organs like the spleen may possibly provide a temporary relief after extensive liver resection or severe liver disease or may enable treatment of an enzyme deficiency. With time, however, dedifferentiation or malignant transformation of the ectopically transplanted cells may be possible. Thus, in the present study syngenic fetal liver tissue suspensions were transplanted into the spleen of adult male rats and evaluated 2 years thereafter in comparison to orthotopic livers for histopathological changes and (as markers for preneoplastic transformation) for cytochrome P450 (P450) and glutathione S-transferase (GST) isoform expression. Because inducibility of P450 and GST isoforms may be changed in preneoplastic foci, prior to sacrifice animals were additionally treated either with beta-naphthoflavone, phenobarbital, dexamethasone, or the respective solvent. In the 2-year-old grafts more than 70% of the spleen mass was occupied by the transplant. The transplanted hepatocytes were arranged in cord-like structures. Also few bile ducts were present. Morphologically, no signs of malignancy were visible. With all rats, transplant recipients as well as controls, however, discrete nodular structures were seen in the livers. Due to age, both livers and transplants displayed only a low P450 2B1 and 3A2 and GST class alpha and mu isoform expression. No immunostaining for P450 1A1 was visible. At both sites, beta-naphthoflavone, phenobarbital, or dexamethasone treatment enhanced P450 1A1, P450 2B1 and 3A2, or P450 3A2 expression, respectively. No immunostaining for GST class pi isoforms was seen in the transplants. The livers of both transplant recipients and control rats, however, displayed GST pi-positive foci, corresponding to the nodular structures seen histomorphologically. Compared to the surrounding tissue, these foci also exhibited a more pronounced staining for GST class alpha and mu isoforms and a stronger inducibility of the P450 1A

  11. Decreased oxidative stress in prehepatic portal hypertensive rat livers following the induction of diabetes.

    PubMed

    Evelson, P; Llesuy, S; Filinger, E; Rodriguez, R R; Lemberg, A; Scorticati, C; Susemihl, M; Villareal, I; Polo, J M; Peredo, H; Perazzo, J C

    2004-03-01

    1. Oxidative stress (OS) is a biological entity indicated as being responsible for several pathologies, including diabetes. Diabetes can also be associated with human cirrhosis. Portal hypertension (PH), a major syndrome in cirrhosis, produces hyperdynamic splanchnic circulation and hyperaemia. The present study was designed to investigate the occurrence of OS in prehepatic PH rat livers following the induction of diabetes. 2. Five groups of rats were used: control, sham operated, chronic diabetes (induced with a single dose of streptozotocin at 60 mg/kg, i.p.), prehepatic PH and chronic diabetic plus prehepatic PH. The occurrence of OS was determined in liver homogenates by measuring hydroperoxide-initiated chemiluminescence and the activity of anti-oxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase). 3. Prehepatic PH produced a significant increase in hydroperoxide-initiated chemiluminescence in the liver compared with control and sham-operated rats, whereas the liver in chronic diabetic rats showed no difference. However, chemiluminescence values decreased almost by 50% in the chronic diabetic plus prehepatic PH group. Concomitantly, the activities of the anti-oxidant enzymes in chronic diabetes, prehepatic PH and chronic diabetic plus prehepatic PH groups were decreased (P < 0.05 vs control and sham-operated groups). 4. Livers from the chronic diabetic group did not show any evidence of the occurrence of OS, whereas the prehepatic PH group showed the occurrence of OS. The association of PH and chronic diabetes resulted in a significant decrease in the occurrence of OS, which could be explained by an anti-oxidant response to an OS. PMID:15008960

  12. TRANEXAMIC ACID ACTION ON LIVER REGENERATION AFTER PARTIAL HEPATECTOMY: EXPERIMENTAL MODEL IN RATS

    PubMed Central

    SOBRAL, Felipe Antonio; DAGA, Henrique; RASERA, Henrique Nogueira; PINHEIRO, Matheus da Rocha; CELLA, Igor Furlan; MORAIS, Igor Henrique; MARQUES, Luciana de Oliveira; COLLAÇO, Luiz Martins

    2016-01-01

    ABSTRACT Background: Different lesions may affect the liver resulting in harmful stimuli. Some therapeutic procedures to treat those injuries depend on liver regeneration to increase functional capacity of this organ. Aim: Evaluate the effects of tranexamic acid on liver regeneration after partial hepatectomy in rats. Method: 40 rats (Rattus norvegicus albinus, Rodentia mammalia) of Wistar-UP lineage were randomly divided into two groups named control (CT) and tranexamic acid (ATX), with 20 rats in each. Both groups were subdivided, according to liver regeneration time of 32 h or seven days after the rats had been operated. The organ regeneration was evaluated through weight and histology, stained with HE and PCNA. Results: The average animal weight of ATX and CT 7 days groups before surgery were 411.2 g and 432.7 g, and 371.3 g and 392.9 g after the regeneration time, respectively. The average number of mitotic cells stained with HE for the ATX and CT 7 days groups were 33.7 and 32.6 mitosis, and 14.5 and 14.9 for the ATX and CT 32 h groups, respectively. When stained with proliferating cell nuclear antigen, the numbers of mitotic cells counted were 849.7 for the ATX 7 days, 301.8 for the CT 7 days groups, 814.2 for the ATX 32 hand 848.1 for the CT 32 h groups. Conclusion: Tranexamic acid was effective in liver regeneration, but in longer period after partial hepatectomy. PMID:27438036

  13. Cytoprotective effects of carvedilol against oxygen free radical generation in rat liver.

    PubMed

    Ronsein, Graziella Eliza; Guidi, Débora Bonelli; Benassi, Jean Carlo; Filho, Danilo Wilhelm; Pedrosa, Roberto Coury; Pedrosa, Rozangela Curi

    2005-01-01

    The protective effects of carvedilol, an antihypertensive agent, against oxidative injury caused by acetaminophen were studied in rat liver. Male Wistar rats (250 +/- 30 g) were pre-treated with carvedilol (3.6 mg/kg, p.o.) for 10 days and on the 11th day received an overdose of acetaminophen (800 mg/kg, p.o.). Four hours after acetaminophen administration, blood was collected to determine serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT). After that, rats were killed and the livers were excised to determine reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARS) and carbonyl protein contents, and the activity of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione S-transferase (GST), and also the DNA damage index. Acetaminophen significantly increased the levels of TBARS, the DNA damage and SOD, AST and ALT activities. Carvedilol was able to prevent lipid peroxidation, protein carbonilation and DNA fragmentation caused by acetaminophen. Moreover, this drug prevented increases in SOD, AST and ALT activities. These results show that carvedilol exerts cytoprotective effects against oxidative injury caused by acetaminophen in rat liver. These effects are probably related to the O2*- scavenging property of carvedilol or its metabolites. PMID:16156951

  14. Healing and Preventive Effects of Calcium Alginate on Carbon Tetrachloride Induced Liver Injury in Rats

    PubMed Central

    Khotimchenko, Yuri S.; Khotimchenko, Maxim Y.

    2004-01-01

    The purpose of this study was to investigate the pharmacological effects of calcium alginate on carbon tetrachloride (CCL4)-induced hepatotoxicity in rats. The study included two experiments. In the first experiment the animals were given daily CCL4 through gavage for 7 days and then 10, 50, or 250 mg/kg b.w. of calcium alginate for 21 days. The increased bilirubin level, enhanced alanine and aspartate aminotransferase activity in plasma and reduced liver glycogen content induced by CCL4 were partly normalized by alginate administration in a dose-dependent manner. In addition, alginate significantly improved CCL4-induced alterations of pro-oxidant and antioxidant biochemical parameters in liver and plasma compared to those of rats administered CCL4. In the second experiment the animals were given daily 10, 50 or 250 mg/kg b.w. of calcium alginate for 21 days before 7-day administration of CCL4. Pretreatment with alginate before CCL4 administration resulted in significantly inhibited increase of the blood enzymatic activities of alanine and aspartate aminotransferases and bilirubin level in a dose-dependent manner. Also, preliminary administration of alginate prevented elevation of lipid peroxidation products and reduction of liver glutathione content in rats given CCL4. These results suggest that calcium alginate exerts healing and preventive effects on CCL4-induced hepatotoxicity in rats.

  15. Adenosine triphosphate-dependent copper transport in isolated rat liver plasma membranes.

    PubMed Central

    Dijkstra, M; In 't Veld, G; van den Berg, G J; Müller, M; Kuipers, F; Vonk, R J

    1995-01-01

    The process of hepatobiliary copper (Cu) secretion is still poorly understood: Cu secretion as a complex with glutathione and transport via a lysosomal pathway have been proposed. The recent cloning and sequencing of the gene for Wilson disease indicates that Cu transport in liver cells may be mediated by a Cu transporting P-type ATPase. Biochemical evidence for ATP-dependent Cu transport in mammalian systems, however, has not been reported so far. We have investigated Cu transport in rat liver plasma membrane vesicles enriched in canalicular or basolateral membranes in the presence and absence of ATP (4 mM) and an ATP-regenerating system. The presence of ATP clearly stimulated uptake of radiolabeled Cu (64Cu, 10 microM) into canalicular plasma membrane vesicles and, to a lesser extent, also into basolateral plasma membrane vesicles. ATP-dependent Cu transport was dose-dependently inhibited by the P-type ATPase inhibitor vanadate, and showed saturation kinetics with an estimated Km of 8.6 microM and a Vmax of 6.9 nmol/min/mg protein. ATP-stimulated Cu uptake was similar in canalicular membrane vesicles of normal Wistar rats and those of mutant GY rats, expressing a congenital defect in the activity of the ATP-dependent canalicular glutathione-conjugate transporter (cMOAT). These studies demonstrate the presence of an ATP-dependent Cu transporting system in isolated plasma membrane fractions of rat liver distinct from cMOAT. PMID:7814642

  16. Effect of zinc deficiency of expression of specific mRNAs in rat liver

    SciTech Connect

    Chen, S.J.; Kimball, S.R.; Leure-duPree, A.E.; Jefferson, L.S. )

    1991-03-15

    Retinol is released from the liver bound to a specific transport protein, retinol binding protein (RBP), which binds to transthyretin (TTR) to transport retinol to the retinal pigment epithelium for use in the visual cycle. The synthesis of RBP as well as the transport of vitamin A from the liver is especially sensitive to zinc deficiency (ZD). Impaired hepatic synthesis of RBP has been reported in zinc-deficient rats. In the present study, the effect of ZD on the expression of mRNAs in the liver was examined by isolating total RNA from control, pair-fed, and zinc-deficient rats and translating the RNA in a messenger-dependent reticulocyte lysate. The radiolabeled translation products were analyzed by two-dimensional gel electrophoresis followed by autoradiography. The amounts of 12 of the approximately 200 radiolabeled translation products which could be distinguished were found to be altered in zinc-deficient compare to control samples. To investigate the expression of a specific mRNA, a cDNA to TTR was employed to probe the RNA samples. Slot blot analysis revealed that TTR mRNA was reduced to 57 {plus minus} 14% of the control in pair-fed rats to 29 {plus minus} 19% of control in zinc-deficient rats. The decrease in TTR mRNA is consistent with the observation that serum TTR is decreased during zinc deficiency caused by cirrhosis.

  17. The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

    NASA Technical Reports Server (NTRS)

    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.

  18. Effect of physical training on liver expression of activin A and follistatin in a nonalcoholic fatty liver disease model in rats.

    PubMed

    Silva, R N; Bueno, P G; Avó, L R S; Nonaka, K O; Selistre-Araújo, H S; Leal, A M O

    2014-09-01

    Nonalcoholic fatty liver disease (NAFLD) is characterized by fat accumulation in the liver and is associated with obesity and insulin resistance. Activin A is a member of the transforming growth factor beta (TGF)-β superfamily and inhibits hepatocyte growth. Follistatin antagonizes the biological actions of activin. Exercise is an important therapeutic strategy to reduce the metabolic effects of obesity. We evaluated the pattern of activin A and follistatin liver expression in obese rats subjected to swimming exercise. Control rats (C) and high-fat (HF) diet-fed rats were randomly assigned to a swimming training group (C-Swim and HF-Swim) or a sedentary group (C-Sed and HF-Sed). Activin βA subunit mRNA expression was significantly higher in HF-Swim than in HF-Sed rats. Follistatin mRNA expression was significantly lower in C-Swim and HF-Swim than in either C-Sed or HF-Sed animals. There was no evidence of steatosis or inflammation in C rats. In contrast, in HF animals the severity of steatosis ranged from grade 1 to grade 3. The extent of liver parenchyma damage was less in HF-Swim animals, with the severity of steatosis ranging from grade 0 to grade 1. These data showed that exercise may reduce the deleterious effects of a high-fat diet on the liver, suggesting that the local expression of activin-follistatin may be involved.

  19. Effect of physical training on liver expression of activin A and follistatin in a nonalcoholic fatty liver disease model in rats

    PubMed Central

    Silva, R.N.; Bueno, P.G.; Avó, L.R.S.; Nonaka, K.O.; Selistre-Araújo, H.S.; Leal, A.M.O.

    2014-01-01

    Nonalcoholic fatty liver disease (NAFLD) is characterized by fat accumulation in the liver and is associated with obesity and insulin resistance. Activin A is a member of the transforming growth factor beta (TGF)-β superfamily and inhibits hepatocyte growth. Follistatin antagonizes the biological actions of activin. Exercise is an important therapeutic strategy to reduce the metabolic effects of obesity. We evaluated the pattern of activin A and follistatin liver expression in obese rats subjected to swimming exercise. Control rats (C) and high-fat (HF) diet-fed rats were randomly assigned to a swimming training group (C-Swim and HF-Swim) or a sedentary group (C-Sed and HF-Sed). Activin βA subunit mRNA expression was significantly higher in HF-Swim than in HF-Sed rats. Follistatin mRNA expression was significantly lower in C-Swim and HF-Swim than in either C-Sed or HF-Sed animals. There was no evidence of steatosis or inflammation in C rats. In contrast, in HF animals the severity of steatosis ranged from grade 1 to grade 3. The extent of liver parenchyma damage was less in HF-Swim animals, with the severity of steatosis ranging from grade 0 to grade 1. These data showed that exercise may reduce the deleterious effects of a high-fat diet on the liver, suggesting that the local expression of activin-follistatin may be involved. PMID:25075578

  20. Butyrate protects rat liver against total hepatic ischemia reperfusion injury with bowel congestion.

    PubMed

    Liu, Bin; Qian, Jianmin; Wang, Qingbao; Wang, Fangrui; Ma, Zhenyu; Qiao, Yingli

    2014-01-01

    Hepatic ischemia/reperfusion (I/R) injury is an unavoidable consequence of major liver surgery, especially in liver transplantation with bowel congestion, during which endotoxemia is often evident. The inflammatory response aggravated by endotoxin after I/R contributes to liver dysfunction and failure. The purpose of the present study was to investigate the protective effect of butyrate, a naturally occurring four-carbon fatty acid in the body and a dietary component of foods such as cheese and butter, on hepatic injury complicated by enterogenous endotoxin, as well as to examine the underlying mechanisms involved. SD rats were subjected to a total hepatic ischemia for 30 min after pretreatment with either vehicle or butyrate, followed by 6 h and 24 h of reperfusion. Butyrate preconditioning markedly improved hepatic function and histology, as indicated by reduced transaminase levels and ameliorated tissue pathological changes. The inflammatory factors levels, macrophages activation, TLR4 expression, and neutrophil infiltration in live were attenuated by butyrate. Butyrate also maintained the intestinal barrier structures, reversed the aberrant expression of ZO-1, and decreased the endotoxin translocation. We conclude that butyrate inhibition of endotoxin translocation, macrophages activation, inflammatory factors production, and neutrophil infiltration is involved in the alleviation of total hepatic I/R liver injury in rats. This suggests that butyrate should potentially be utilized in liver transplantation.

  1. Ameliorating effect of Allium Sativum on high-fat diet induced fatty liver in albino rats

    PubMed Central

    Qamar, Aisha; Usmani, Ambreen; Waqar, Humera; Siddiqui, Asma; Kumar, Hemant

    2016-01-01

    Objective: To assess the hepatoprotective effect provided by fresh garlic on fatty liver induced by high-fat diet. Methods: This experimental study was carried out at BMSI, JPMC from October to November 2008. Thirty adult albino rats, 200-240 gram weight, were divided into three groups. Group A received control diet, Group B received high-fat diet (20 mg butter/100 gm diet) and Group C received high-fat diet with fresh garlic (20 mg butter with 6 gm fresh garlic/100 gm diet). The groups were further divided on the basis of duration of treatment, four weeks and eight weeks respectively. The rats were sacrificed, liver removed, weighed and relative liver weight calculated. Hepatic tissue was processed and tissue slides stained with haematoxylin and eosin. Results: There was significant increase in relative liver weight in group B animals as compared to the control animals, which decreased significantly in group C. Haematoxylin and eosin stained sections revealed ballooned hepatocytes having vesicular appearance with pyknotic nuclei in high-fat group which were preserved to a great extent in group C animals. Conclusion: This study has shown that use of fresh garlic along with high-fat diet prevents its damaging effects on liver to a great extent. PMID:27182249

  2. Intramuscular relative dose response (RDR) determination of liver vitamin A stores in rats.

    PubMed

    Zachman, R D; Chen, X M

    1991-02-01

    This study questioned whether the relative dose response (RDR) method to detect liver stores of vitamin A could be used by intramuscular administration of the vitamin. Vitamin A-deficient and reference rat serum retinol levels were determined by HPLC at zero time and then again 5 h after an intramuscular injection of 5.25 mumol/kg retinyl palmitate. The RDR percentage was calculated: [(A5-A0)/(A5)] x 100. The 5-h RDR was determined in 20 deficient and 16 reference diet rats and a clear relationship to liver retinyl palmitate concentration was demonstrated. At a liver retinyl palmitate concentration of less than 0.105 mumol/g, all RDR values were greater than 20%. When the liver retinyl palmitate was greater than 0.122 mumol/g the RDR was less than 20%. This study suggests that the intramuscular RDR is a valid tool for estimating liver retinyl palmitate in populations in which the oral RDR cannot be administered. PMID:1825326

  3. Expression of Redox Factor-1 in Early Injury Period After Liver Transplantation in Rat Model

    PubMed Central

    Zhang, Ping; Du, Xiaohong; Sun, Zhipeng; Xu, Lijun

    2009-01-01

    The aims of this study were to observe the relationship between injury of graft and expression of redox factor-1 (Ref-1) in early period (24 h) after liver transplantation in rat model. One hundred and fifty adult male Wister rats were randomly divided into three groups including liver transplant group, sham surgery group and untreated control group. After liver transplantation, animals were sacrificed at different time points, and the changes and significance of the expression of Ref-1 were then explored by immunohistochemistry, serology and histopathology. As compared with sham surgery group and untreated control group, the expression of Ref-1 protein in transplant group was stronger in early period after liver transplantation. With pathology analysis, lots of infiltrating inflammation cells were found around the portal veins. Hepatic tissues were injury. However, the injury in sham surgery and untreated control group were comparatively slight. The serum ALT and AST levels reached the peak at 6-12 h, and decreased significantly after 12 h. These data suggested that the degree of liver injury in earlier period after transplantation peaked at 6 h and then decreased. And Ref-1 protein induced by hepatic ischemic reperfusion injury might play a critical role in repairing the injury. PMID:19728933

  4. Aqueous extract of Securidaca longepedunculata root induce redox imbalance in male rat liver and kidney.

    PubMed

    Ajiboye, T O; Salau, A K; Yakubu, M T; Oladiji, A T; Akanji, M A; Okogun, J I

    2010-08-01

    The effect of aqueous extract of Securidaca longepedunculata root on redox homeostasis in male rat liver and kidney was investigated. Rats were grouped into four: A, B, C and D, where A (the control) received orally 1 mL of distilled water; B, C and D (test groups) received orally 200, 400 and 800 mg/kg body weight of the extract, respectively, for 28 days. Extract administration significantly reduced (p < .05) alkaline phosphatase activity in the liver and kidney with corresponding increases in the serum. Acid phosphatase activity increased significantly (p < .05) in the liver and kidney, while there was no significant change (p > .05) in the serum acid phosphatase activity. There was also significant decrease (p < .05) in the activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase in the liver and kidney. Liver and kidney levels of GSH, vitamins C and E were also significantly reduced (p < .05). Serum malonidialdehyde and lipid hydroperoxide increased significantly (p < .05) in all the extract-treated groups. The available data from this study revealed that aqueous extract of S. longepedunculata root exerted its toxicity in the animals by depleting the antioxidant systems. This may consequently expose the cells and cellular macromolecules to oxidative damage by reactive oxygen species generated either from the metabolism of the extract or other in vivo means. PMID:20144964

  5. A model of chlorpyrifos distribution and its biochemical effects on the liver and kidneys of rats.

    PubMed

    Tanvir, E M; Afroz, R; Chowdhury, Maz; Gan, S H; Karim, N; Islam, M N; Khalil, M I

    2016-09-01

    This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.

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

    PubMed Central

    Wong, Weng-Yew; Poudyal, Hemant; Ward, Leigh C.; Brown, Lindsay

    2012-01-01

    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. PMID:23201770

  7. Alloimmune Activation Promotes Anti-Cancer Cytotoxicity after Rat Liver Transplantation

    PubMed Central

    Lacotte, Stéphanie; Oldani, Graziano; Slits, Florence; Orci, Lorenzo A.; Rubbia-Brandt, Laura; Morel, Philippe; Mentha, Gilles; Toso, Christian

    2014-01-01

    Liver transplantation for hepatocellular carcinoma (HCC) results in a specific condition where the immune response is potentially directed against both allogeneic and cancer antigens. We have investigated the level of anti-cancer immunity during allogeneic immune response. Dark Agouti-to-Lewis and Lewis-to-Lewis rat liver transplantations were performed and the recipients anti-cancer immunity was analysed at the time of alloimmune activation. The occurrence of rejection in the allogeneic recipients was confirmed by a shorter survival (p<0.01), increased liver function tests (p<0.01), the presence of signs of rejection on histology, and a donor-specific ex vivo mixed lymphocyte reaction. At the time of alloimmune activation, blood mononuclear cells of the allogeneic group demonstrated increased anti-cancer cytotoxicity (p<0.005), which was related to an increased natural killer (NK) cell frequency (p<0.05) and a higher monocyte/macrophage activation level (p<0.01). Similarly, liver NK cell anti-cancer cytotoxicity (p<0.005), and liver monocyte/macrophage activation levels (p<0.01) were also increased. The alloimmune-associated cytotoxicity was mediated through the NKG2D receptor, whose expression was increased in the rejected graft (p<0.05) and on NK cells and monocyte/macrophages. NKG2D ligands were expressed on rat HCC cells, and its inhibition prevented the alloimmune-associated cytotoxicity. Although waiting for in vivo validation, alloimmune-associated cytotoxicity after rat liver transplantation appears to be linked to increased frequencies and levels of activation of NK cells and monocyte/macrophages, and is at least in part mediated through the NKG2D receptor. PMID:24651497

  8. Streptozotocin-induced diabetes mellitus affects lysosomal enzymes in rat liver

    PubMed Central

    Peres, G.B.; Juliano, M.A.; Aguiar, J.A.K.; Michelacci, Y.M.

    2014-01-01

    It has been previously shown that dextran sulfate administered to diabetic rats accumulates in the liver and kidney, and this could be due to a malfunction of the lysosomal digestive pathway. The aim of the present study was to evaluate the expression and activities of lysosomal enzymes that act upon proteins and sulfated polysaccharides in the livers of diabetic rats. Diabetes mellitus was induced by streptozotocin in 26 male Wistar rats (12 weeks old), while 26 age-matched controls received only vehicle. The livers were removed on either the 10th or the 30th day of the disease, weighed, and used to evaluate the activity, expression, and localization of lysosomal enzymes. A 50-60% decrease in the specific activities of cysteine proteases, especially cathepsin B, was observed in streptozotocin-induced diabetes mellitus. Expression (mRNA) of cathepsins B and L was also decreased on the 10th, but not on the 30th day. Sulfatase decreased 30% on the 30th day, while glycosidases did not vary (or presented a transitory and slight decrease). There were no apparent changes in liver morphology, and immunohistochemistry revealed the presence of cathepsin B in hepatocyte granules. The decrease in sulfatase could be responsible for the dextran sulfate build-up in the diabetic liver, since the action of sulfatase precedes glycosidases in the digestive pathway of sulfated polysaccharides. Our findings suggest that the decreased activities of cathepsins resulted from decreased expression of their genes, and not from general lysosomal failure, because the levels of glycosidases were normal in the diabetic liver. PMID:24820066

  9. Impaired hepatic handling and processing of lysophosphatidylcholine in rats with liver cirrhosis

    SciTech Connect

    Angelico, M.; Alvaro, D.; Cantafora, A.; Masella, R.; Gaudio, E.; Gandin, C.; Ginanni Corradini, S.; Ariosto, F.; Riggio, O.; Capocaccia, L. )

    1991-07-01

    Lysophosphatidylcholine is a major metabolic product in the plasma and cellular turnover of phospholipids, with well-known membrane-toxic and proinflammatory properties. Because the liver plays a key role in plasma lysophosphatidylcholine removal and biotransformation and because virtually nothing is known of these processes in a diseased organ, the hepatobiliary metabolism of lysophosphatidylcholine was investigated in rats with carbon tetrachloride-induced liver cirrhosis. Twelve adult male Wistar rats with histologically confirmed cirrhosis and 8 control animals were fitted with jugular and biliary catheters and allowed to recover. The animals were kept under constant IV infusion of taurocholate (1 mumol/min). Two microcuries of sn-1{sup 14}Cpalmitoyl-lysophosphatidylcholine was administered as a single bolus. The fate of the injected radioactivity, including removal from plasma, uptake, and subcellular location in the liver and molecular and aggregative forms, was studied by combined chromatographic and radiochemical methods. Major findings were (a) that lysophosphatidylcholine has a prolonged permanence in plasma of cirrhotic rats, due both to decreased hepatic clearance and to depressed conversion into phosphatidylcholine; (b) that the rate of lysophosphatidylcholine acylation is much slower in the cirrhotic than in the normal liver, both at the microsomal and at the cytosolic level; (c) that cytosolic lysophosphatidylcholine in the cirrhotic liver, but not in the normal liver, is predominantly non-protein bound; (d) that the strict molecular selectivity of lysophosphatidylcholine acylation observed in controls is partially lost in cirrhosis; and (e) that a consistent fraction of lysophosphatidylcholine is converted into triacylglycerols in cirrhotics but not in controls.

  10. Alloimmune activation promotes anti-cancer cytotoxicity after rat liver transplantation.

    PubMed

    Lacotte, Stéphanie; Oldani, Graziano; Slits, Florence; Orci, Lorenzo A; Rubbia-Brandt, Laura; Morel, Philippe; Mentha, Gilles; Toso, Christian

    2014-01-01

    Liver transplantation for hepatocellular carcinoma (HCC) results in a specific condition where the immune response is potentially directed against both allogeneic and cancer antigens. We have investigated the level of anti-cancer immunity during allogeneic immune response. Dark Agouti-to-Lewis and Lewis-to-Lewis rat liver transplantations were performed and the recipients anti-cancer immunity was analysed at the time of alloimmune activation. The occurrence of rejection in the allogeneic recipients was confirmed by a shorter survival (p<0.01), increased liver function tests (p<0.01), the presence of signs of rejection on histology, and a donor-specific ex vivo mixed lymphocyte reaction. At the time of alloimmune activation, blood mononuclear cells of the allogeneic group demonstrated increased anti-cancer cytotoxicity (p<0.005), which was related to an increased natural killer (NK) cell frequency (p<0.05) and a higher monocyte/macrophage activation level (p<0.01). Similarly, liver NK cell anti-cancer cytotoxicity (p<0.005), and liver monocyte/macrophage activation levels (p<0.01) were also increased. The alloimmune-associated cytotoxicity was mediated through the NKG2D receptor, whose expression was increased in the rejected graft (p<0.05) and on NK cells and monocyte/macrophages. NKG2D ligands were expressed on rat HCC cells, and its inhibition prevented the alloimmune-associated cytotoxicity. Although waiting for in vivo validation, alloimmune-associated cytotoxicity after rat liver transplantation appears to be linked to increased frequencies and levels of activation of NK cells and monocyte/macrophages, and is at least in part mediated through the NKG2D receptor.

  11. Danaparoid sodium reduces ischemia/reperfusion-induced liver injury in rats by attenuating inflammatory responses.

    PubMed

    Harada, Naoaki; Okajima, Kenji; Kohmura, Hidefumi; Uchiba, Mitsuhiro; Tomita, Tsutomu

    2007-01-01

    This study was undertaken to examine the mechanism by which danaparoid sodium (DS), a heparinoid that contains mainly heparan sulfate, prevents reperfusion-induced hepatic damage in a rat model of ischemia/reperfusion (I/R)-induced liver injury. Administration of DS significantly reduced liver injury and inhibited the decrease in hepatic tissue blood flow in rats. DS attenuated hepatic I/R-induced increases in hepatic tissue levels of tumor necrosis factor (TNF) and myeloperoxidase (MPO) in vivo. In contrast, neither monocytic TNF production nor neutrophil activation was inhibited by DS in vitro. DS enhanced I/R-induced increases in levels of calcitonin-gene related peptide (CGRP), a neuropeptide released from sensory neurons, and of 6-ketoprostaglandin (PG) F (1a) , a stable metabolite of PGI (2) , in liver tissues. The therapeutic effects of DS were not seen in animals pretreated with capsazepine, an inhibitor of sensory neuron activation. The distribution of heparan sulfate in the perivascular area was significantly increased by DS administration in this rat model. DS significantly increased CGRP release from isolated rat dorsal root ganglion neurons (DRG) in vitro, while DX-9065a, a selective inhibitor of activated factor X, did not. DS enhanced anandamide-induced CGRP release from DRG in vitro. These observations strongly suggested that DS might reduce I/R-induced liver injury in rats by attenuating inflammatory responses. These therapeutic effects of DS might be at least partly explained by its enhancement of sensory neuron activation, leading to the increase the endothelial production of PGI (2) . PMID:17200774

  12. Rat liver regeneration following ablation with irreversible electroporation

    PubMed Central

    Bruinsma, Bote G.; Jaramillo, Maria; Yarmush, Martin L.

    2016-01-01

    During the past decade, irreversible electroporation (IRE) ablation has emerged as a promising tool for the treatment of multiple diseases including hepatic cancer. However, the mechanisms behind the tissue regeneration following IRE ablation have not been investigated. Our results indicate that IRE treatment immediately kills the cells at the treatment site preserving the extracellular architecture, in effect causing in vivo decellularization. Over the course of 4 weeks, progenitor cell differentiation, through YAP and notch pathways, together with hepatocyte expansion led to almost complete regeneration of the ablated liver leading to the formation of hepatocyte like cells at the ablated zone. We did not observe significant scarring or tumor formation at the regenerated areas 6 months post IRE. Our study suggests a new model to study the regeneration of liver when the naïve extracellular matrix is decellularized in vivo with completely preserved extracellular architecture. PMID:26819842

  13. Comparative metabolism of chloroacetamide herbicides and selected metabolites in human and rat liver microsomes.

    PubMed Central

    Coleman, S; Linderman, R; Hodgson, E; Rose, R L

    2000-01-01

    Acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methyl-phenyl)-acetamide], alachlor [N-(methoxymethyl)-2-chloro-N-(2, 6-diethyl-phenyl)acetamide], butachlor [N-(butoxymethyl)-2-chloro-N-(2,6-diethyl-phenyl)acetamide], and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide] are pre-emergent herbicides used in the production of agricultural crops. These herbicides are carcinogenic in rats: acetochlor and alachlor cause tumors in the nasal turbinates, butachlor causes stomach tumors, and metolachlor causes liver tumors. It has been suggested that the carcinogenicity of these compounds involves a complex metabolic activation pathway leading to a DNA-reactive dialkylbenzoquinone imine. Important intermediates in this pathway are 2-chloro-N-(2,6-diethylphenyl)acetamide (CDEPA) produced from alachlor and butachlor and 2-chloro-N-(2-methyl-6-ethylphenyl)acetamide (CMEPA) produced from acetochlor and metolachlor. Subsequent metabolism of CDEPA and CMEPA produces 2,6-diethylaniline (DEA) and 2-methyl-6-ethylaniline (MEA), which are bioactivated through para-hydroxylation and subsequent oxidation to the proposed carcinogenic product dialkylbenzoquinone imine. The current study extends our earlier studies with alachlor and demonstrates that rat liver microsomes metabolize acetochlor and metolachlor to CMEPA (0.065 nmol/min/mg and 0.0133 nmol/min/mg, respectively), whereas human liver microsomes can metabolize only acetochlor to CMEPA (0.023 nmol/min/mg). Butachlor is metabolized to CDEPA to a much greater extent by rat liver microsomes (0.045 nmol/min/mg) than by human liver microsomes (< 0.001 nmol/min/mg). We have determined that both rat and human livers metabolize both CMEPA to MEA (0.308 nmol/min/mg and 0.541 nmol/min/mg, respectively) and CDEPA to DEA (0.350 nmol/min/mg and 0.841 nmol/min/mg, respectively). We have shown that both rat and human liver microsomes metabolize MEA (0.035 nmol/min/mg and 0.069 nmol/min/mg, respectively

  14. [SUSTENTOCYTE NUMBERS IN THE NEONATAL PERIOD IN THE OFFSPRING OF FEMALE RATS WITH EXPERIMENTAL LIVER DAMAGE].

    PubMed

    Briukhin, G V; Sizonenko, M L

    2016-01-01

    On serial histological sections of the testes, stained with hematoxylin-eosin, using a morphometric device, the total numbers of spermatogenic cells and sustentocytes (Sertoli cells) were measured in the convoluted seminiferous tubules of neonatal rat pups. Experimental groups consisted of rats born from females with experimental liver damage of various origins--autoimmune (n = 33), toxic (n = 32), alcoholic (n = 12), and medicinal (n = 27). The control group included pups born from normal female rats (n = 14). In experimental rats both increase and decrease of the total number of sustentocytes was detected. In the animals of most of the experimental groups, sustentocyte cell index reflecting the ratio of the number of spermatogenic cells and sustentocytes, was decreased. PMID:27487667

  15. Effects of six anaesthetic agents on UDP-glucuronic acid and other nucleotides in rat liver.

    PubMed

    Christensson, P I; Eriksson, G

    1985-08-01

    Anaesthesia affects the liver nucleotide pool. It was the aim of the present study to examine how anaesthesia for 60 min with pentobarbital, ketamin + diazepam, halothane, enflurane and isoflurane may influence the nucleotide pool in the rat liver, studied with isotachophoresis. It was found that none of the agents gave both safe and reproducible anaesthesia without affecting the nucleotide pools or affecting the experiments in some other way. Halothane and isoflurane were the two best alternatives with respect to both efficiency and safety. Isoflurane may be preferable since it gives a higher energy charge.

  16. Hepatic metabolism of 7,12-dimethylbenz(a)anthracene in male, female, and ovariectomized Sprague-Dawley rats

    SciTech Connect

    Vater, S.T.; Baldwin, D.M.; Warshawsky, D. )

    1991-01-15

    Dimethylbenz(a)anthracene (DMBA) is a potent inducer of mammary tumors in intact female Sprague-Dawley rats, but not in males or ovariectomized females (OVX). Qualitative and quantitative aspects of hepatic metabolism of DMBA were examined in these three groups of rats, using the nonrecirculating perfused liver, to determine whether the production of proximate carcinogenic metabolites of DMBA by the liver differed among these groups in the same manner as does sensitivity to tumor induction. DMBA was infused into the liver at a constant rate for 60 min. Rates of appearance of DMBA and its metabolites were measured in perfusate and bile during the infusion period and the first 60 min thereafter. The maximum rate of appearance of total metabolites in the perfusate, seen at the end of the infusion period, was highest in the intact female (2.6 +/- 0.3 nmol/(g x min)), slightly lower in the OVX (2.3 +/- 0.2 nmol/(g x min)) and significantly lower in the male (1.0 +/- 0.1 nmol/(g x min)). The rates of appearance of metabolites in the bile showed the same order as those seen in the perfusate. The major metabolites extracted from the perfusate in all three groups were dihydrodiols, hydroxymethyl metabolites, and several unidentified metabolites. The 3,4-dihydrodiol, a proximate carcinogenic metabolite, appeared in the perfusate at higher rates in the intact female and OVX than in the male. Hydrolysis of bile samples showed that glucuronidation was a major pathway in the excretion of DMBA metabolites in bile. High performance liquid chromatographic analysis indicated that hydrolysis of DMBA glucuronides yielded the 7- and 12-hydroxymethyl metabolites and an unidentified metabolite designated X. The major hydrolysis product in the male was 12-hydroxymethyl while X was found to be the major product in the intact female and OVX.

  17. Acute exercise decreases PTP-1B protein level and improves insulin signaling in the liver of old rats

    PubMed Central

    2013-01-01

    It is now commonly accepted that chronic inflammation associated with obesity during aging induces insulin resistance in the liver. In the present study, we investigated whether the improvement in insulin sensitivity and insulin signaling, mediated by acute exercise, could be associated with modulation of protein-tyrosine phosphatase 1B (PTP-1B) in the liver of old rats. Aging rats were subjected to swimming for two 1.5-h long bouts, separated by a 45 min rest period. Sixteen hours after the exercise, the rats were sacrificed and proteins from the insulin signaling pathway were analyzed by immunoblotting. Our results show that the fat mass was increased in old rats. The reduction in glucose disappearance rate (Kitt) observed in aged rats was restored 16 h after exercise. Aging increased the content of PTP-1B and attenuated insulin signaling in the liver of rats, a phenomenon that was reversed by exercise. Aging rats also increased the IRβ/PTP-1B and IRS-1/PTP-1B association in the liver when compared with young rats. Conversely, in the liver of exercised old rats, IRβ/PTP-1B and IRS-1/PTP-1B association was markedly decreased. Moreover, in the hepatic tissue of old rats, the insulin signalling was decreased and PEPCK and G6Pase levels were increased when compared with young rats. Interestingly, 16 h after acute exercise, the PEPCK and G6Pase protein level were decreased in the old exercised group. These results provide new insights into the mechanisms by which exercise restores insulin signalling in liver during aging. PMID:23442260

  18. Expression patterns and action analysis of genes associated with inflammatory responses during rat liver regeneration

    PubMed Central

    Shao, Heng-Yi; Zhao, Li-Feng; Xu, Cun-Shuan

    2007-01-01

    AIM: To study the relationship between inflammatory response and liver regeneration (LR) at transcriptional level. METHODS: After partial hepatectomy (PH) of rats, the genes associated with inflammatory response were obtained according to the databases, and the gene expression changes during LR were checked by the Rat Genome 230 2.0 array. RESULTS: Two hundred and thirty-nine genes were associated with liver regeneration. The initial and total expressing gene numbers found in initiation phase (0.5-4 h after PH), G0/G1 transition (4-6 h after PH), cell proliferation (6-66 h after PH), cell differentiation and structure-function reconstruction (66-168 h after PH) of liver regeneration were 107, 34, 126, 6 and 107, 92, 233, 145 respectively, showing that the associated genes were mainly triggered at the beginning of liver regeneration, and worked at different phases. According to their expression similarity, these genes were classified into 5 groups: only up-regulated, predominantly up-, only down-, predominantly down-, up- and down-, involving 92, 25, 77, 14 and 31 genes, respectively. The total times of their up- and down-regulated expression were 975 and 494, respectively, demonstrating that the expressions of the majority of genes were increased, and that of a few genes were decreased. Their time relevance was classified into 13 groups, showing that the cellular physiological and biochemical activities were staggered during liver regeneration. According to gene expression patterns, they were classified into 33 types, suggesting that the activities were diverse and complex during liver regeneration. CONCLUSION: Inflammatory response is closely associated with liver regeneration, in which 239 LR-associated genes play an important role. PMID:17230604

  19. Lactoferrin protects against chemical-induced rat liver fibrosis by inhibiting stellate cell activation.

    PubMed

    Tung, Yu-Tang; Tang, Ting-Yu; Chen, Hsiao-Ling; Yang, Shang-Hsun; Chong, Kowit-Yu; Cheng, Winston T K; Chen, Chuan-Mu

    2014-01-01

    Liver diseases, which can be caused by alcohol abuse, chemical intoxication, viral hepatitis infection, and autoimmune disorders, are a significant health issue because they can develop into liver fibrosis and cirrhosis. Lactoferrin (LF), a siderophilic protein with 2 iron-binding sites, has been demonstrated to possess a multitude of biological functions, including antiinflammation, anticancer, and antimicrobial effects, as well as immunomodulatory-enhancing functions. In the current study, we induced hepatotoxicity in rats with dimethylnitrosamine (DMN) to establish a situation that would enable us to evaluate the hepatoprotective effects of LF against hepatic injury. Our results showed that DMN-induced hepatic pathological damage significantly decreased the body weight and liver index, increased the mRNA and protein levels of collagen α-1(I) (ColIα-1) and α-smooth muscle actin, and increased the hydroxyproline content. However, treatment with LF significantly increased body weight and liver index, decreased the mRNA and protein levels of ColIα-1 and α-smooth muscle actin, and suppressed the hydroxyproline content when compared with the DMN-treated group. Liver histopathology also showed that low-dose LF (100mg/kg of body weight) or high-dose LF (300 mg/kg of body weight) could significantly reduce the incidences of liver lesions induced by DMN. These results suggest that the LF exhibits potent hepatoprotection against DMN-induced liver damage in rats and that the hepatoprotective effects of LF may be due to the inhibition of collagen production and to stellate cell activation. PMID:24731632

  20. Protective role of curcumin against nicotine-induced genotoxicity on rat liver under restricted dietary protein.

    PubMed

    Bandyopadhyaya, Gargi; Sinha, Surajit; Chattopadhyay, Braja Dulal; Chakraborty, Anindita

    2008-07-01

    Nicotine, the well known addictive chemical of tobacco and active medication for several diseases, has proven to be a potential genotoxic compound. Although it is absorbed through lungs with smoking and mainly metabolized in liver, its effect on liver injuries is not clear. This study was designed to evaluate the genotoxicity of nicotine and corresponding the protective role of curcumin against nicotine on liver of female populations particularly who used tobacco but deprived of healthy diet. The effects were investigated by measurement of total DNA concentration of liver tissues and Comet assay of liver tissue DNA damage of female rats maintained under normal and restricted protein diets. Total DNA contents in the liver tissues were observed to decrease more significantly (P<0.001) by nicotine in both dietary conditions. Significant (P<0.01) increase of total DNA content in normal dietary condition and more significant (P<0.001) increase of total DNA content in protein restricted condition of the liver tissues were observed due to curcumin supplementations. Highly significant (P<0.001) DNA damages (37% in normal diet and 56% in protein restricted diet) of the liver tissues were observed due to nicotine treatment. Curcumin reduced the nicotine-induced DNA damage percentage of the liver tissues more significantly (P<0.001) in protein restricted condition. Curcumin proved its potential to function against genotoxic effect by reducing the DNA damage activity of nicotine and minimized the percentage of DNA damage (50-60%) in protein restricted dietary condition. The degree of nicotine-induced genotoxicity therefore can be effectively compensated by the protective effect of curcumin in protein stress condition. PMID:18508046

  1. Monitoring dihydrodiol polyaromatic hydrocarbon metabolites produced by the freshwater microalgae Selenastrum capricornutum.

    PubMed

    Hernández Blanco, Fernando José; García de Llasera, Martha Patricia

    2016-09-01

    We found that microalgae exposed to a mixture of polycyclic aromatic hydrocarbons (PAHs) did not show growth inhibition. Thus, we assumed that they could metabolize these compounds. In this study, the dihydrodiol-type PAH metabolites of benzo(a)pyrene (BaP), benzo(a)anthracene (BaA), benzo(b)fluoranthene (BbF) and benzo(k)fluoranthene (BkF) produced by the freshwater microalgae Selenastrum capricornutum were monitored and quantified using high-performance liquid chromatography with fluorescence detection (HPLC-FD) techniques. Exposure bioassays with S. capricornutum were performed using a 266 ng mL(-1) mixture of PAHs at different exposure times (0.75, 1, 3, 8, 16, 24 and 48 h) under controlled temperature (25 °C); the dihydrodiol metabolites formed in the liquid medium and the biomass were quantified. Metabolite identities were confirmed using HPLC-mass spectrometry; most of the metabolites formed were derived from BaA degradation. At 48 h after exposure 5,6-dBaA and 8,9-dBaA/10,11-dBaA were present in the liquid medium at 20% and 67% of the initial mass of BaA, respectively. Three metabolites of BaP were monitored in the liquid medium and biomass and, at 24 h, 4,5-dBaP accounted for 19%; , 7,8-dBaP, 5%; and 9,10-dBaP, 5% relative to the initial BaP mass. Microalgae exposed to BbF showed the presence of 1,2-dBbF and 9,10-dBbF (at 0.3% and 0.1% of the initial BbF mass, respectively) and those exposed to BkF produced 8,9-dBkF (6.5% of the initial BkF mass) in the liquid medium. Seven unknown compounds were formed after exposure; two compounds were identified as the metabolites of BaA and BaP. The results could facilitate the elucidation of the controversial biodegradation mechanism in microalgae. PMID:27258898

  2. Effect of magnesium deficiency on various mineral concentrations in rat liver.

    PubMed

    Kim, Ki Hyun; Ishizaki, Natsumi; Iguchi, Erika; Funaba, Masayuki; Matsui, Tohru

    2011-12-01

    Magnesium (Mg) deficiency is well known to affect metabolism of some trace minerals. We investigated the effect of Mg deficiency on hepatic concentration of various minerals in rats. Twelve 5-week-old male rats were divided into the groups given a control diet and an Mg-deficient diet. After 4 weeks, liver sample was collected from each rat. The concentrations of 36 minerals were simultaneously determined by a semiquantitative method of inductively coupled plasma-mass spectrometry (ICP-MS). The semiquantitative analysis showed that Mg deficiency significantly increased iron (Fe), copper (Cu), zinc (Zn), gallium (Ga), yttrium (Y), zirconium (Zr), molybdenum (Mo), rhodium (Rh), silver (Ag), and barium (Ba) concentrations, and significantly decreased scandium (Sc) and niobium (Nb) concentrations in rat liver. Then, hepatic Fe, Cu, Zn, Sc, Zr, and Mo concentrations were quantitatively measured, which indicated the similar effects as observed by the semiquantitative analysis. Additionally, the semiquantitative measurements of these minerals were highly correlated to these measurements with the quantitative method, but the measurements were not completely consistent between these analyses. The present study is the first research indicating the changes of hepatic Ga, Y, Zr, Mo, Rh, Ag, Ba, Sc, and Nb concentrations in Mg-deficient rats. The present study also indicates that the semiquantitative analysis with ICP-MS is a valid method for screening analysis to investigate various mineral concentrations in animal tissues. PMID:21465284

  3. Induction of rat kidney gluconeogenesis during acute liver intoxication by carbon tetrachloride.

    PubMed Central

    Faus, M J; Lupiáñez, A; Vargas, A; Sánchez-Medina, F

    1978-01-01

    1. Glucose production from L-lactate was completely inhibited 24h after carbon tetrachloride treatment in liver from 48h-starved rats. The activities of phosphoenolpyruvate carboxykinase, fructose diphosphatase and glucose 6-phosphatase were decreased by this treatment in fed and starved rats, whereas lactate dehydrogenase activity was only decreased in fed animals. 2. The production of glucose by renal cortical slices from fed rats previously treated with carbon tetrachloride was enhanced when L-lactate, pyruvate and glutamine but not fructose were used as glucose precursors. Renal phosphoenolpyruvate carboxykinase activity was increased in this condition. 3. This increase was counteracted by cycloheximide or actinomycin D, suggesting that the effect was due to the synthesis de novo of the enzyme. 4. The pattern of hepatic gluconeogenic metabolites in treated animals was characterized by an increase in lactate, pyruvate, malate and citrate as well as a decrease in glucose 6-phosphate, suggesting an impairment of liver gluconeogenesis in vivo. 5. In contrast, the profile of renal metabolites suggested that gluconeogenesis was operative in the treated rats, as indicated by the marked increase in the content of phosphoenolpyruvate, 2-phosphoglycerate, 3-phosphoglycerate and glucose 6-phosphate. 6. It is postulated that renal gluconeogenesis could contribute to the maintenance of glycaemia in carbon tetrachloride-treated rats. PMID:708398

  4. Protective Effect of Curcumin against the Liver Toxicity Caused by Propanil in Rats

    PubMed Central

    Otuechere, Chiagoziem A.; Abarikwu, Sunny O.; Olateju, Victoria I.; Animashaun, Azeezat L.; Kale, Oluwafemi E.

    2014-01-01

    We investigated the protective effects of curcumin on propanil-induced alterations in biochemical indices in blood and liver of male Wistar rats. The study consisted of four treatment groups, with six animals each, designated as control, propanil (20mg/kg), curcumin(50 mg/kg), and curcumin (50 mg/kg) + propanil (20 mg/kg). Rats were administered their respective doses orally, every other day, for 28 days. Propanil administration elicited significant (P < 0.001) increases in plasma aspartate aminotransferase and alkaline phosphatase activities, by 24% and 56%, respectively, compared to the control. Treatment with propanil elevated bilirubin, creatinine, and total cholesterol levels in rats, but these were not significant relative to controls. Administration of propanil to rats significantly (P < 0.001) increased lipid peroxidation levels. However, catalase activity, vitamin C, and reduced glutathione levels were significantly reduced. Exposure to propanil did not produce any significant changes in packed cell volume, neutrophils, and leukocyte counts. The supplementation of curcumin attenuated the adverse effects of propanil intoxication by reducing lipid peroxidation levels and restored the levels of serum enzymes and reduced glutathione. The present study showed that propanil increased oxidative stress and altered some biochemical parameters in the rats but curcumin could afford some protection to attenuate propanil-induced toxicity in the liver. PMID:27437486

  5. Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water.

    PubMed

    Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

    2015-01-01

    Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury. PMID:26316710

  6. Zonal distribution of protein-acetaldehyde adducts in the liver of rats fed alcohol for long periods.

    PubMed

    Lin, R C; Zhou, F C; Fillenwarth, M J; Lumeng, L

    1993-10-01

    Acetaldehyde, a highly reactive intermediate of alcohol metabolism, has been shown to form adducts with liver proteins in rats fed alcohol for long periods. In this report, the zonal distribution of liver protein-acetaldehyde adducts that formed in vivo was studied by means of histoimmunostaining. Rats were pair-fed alcohol-containing and alcohol-free AIN'76 liquid diets for 2 or 11 wk before they were killed and subjected to whole body perfusion with paraformaldehyde. Each liver was cut into 60-microns-thick slices. Slices were first treated with 10% hydrogen peroxide to eliminate endogenous peroxidase activity. They were then incubated sequentially with rabbit antihemocyanin-acetaldehyde adduct, goat antirabbit serum IgG and rabbit peroxidase-antiperoxidase complex. The liver slices were stained with diaminobenzidine and counterstained with methylgreen. In the livers of rats fed alcohol for 2 wk, peroxidase activity was evident in the perivenous zone but not the periportal zone. No staining was obtained when the primary antibody had been preabsorbed with immobilized hemocyanin-acetaldehyde adduct or if the liver slices were incubated with the unimmunized rabbit IgG. Slight staining of the perivenous zone was seen in the livers of control rats, presumably because of minimal protein-acetaldehyde adduct formation emanating from endogenous acetaldehyde. When rats were fed alcohol for longer periods (e.g., 11 wk), protein-acetaldehyde adducts were still seen predominantly in the perivenous zone, but the distribution pattern was more diffuse than that observed in the livers of rats fed alcohol for only 2 wk. More liver cells produced protein-acetaldehyde adducts when rats were fed the alcohol-containing diet supplemented with cyanamide.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water

    PubMed Central

    Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

    2015-01-01

    Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury. PMID:26316710

  8. Death receptor and mitochondria-mediated hepatocyte apoptosis underlies liver dysfunction in rats exposed to organic pollutants from drinking water.

    PubMed

    Yang, Guanghong; Zhou, Zhiwei; Cen, Yanli; Gui, Xiaolin; Zeng, Qibing; Ao, Yunxia; Li, Qian; Wang, Shiran; Li, Jun; Zhang, Aihua

    2015-01-01

    Persistent organic pollutants in drinking water impose a substantial risk to the health of human beings, but the evidence for liver toxic effect and the underlying mechanism is scarce. This study aimed to examine the liver toxicity and elucidate the molecular mechanism of organic pollutants in drinking water in normal human liver cell line L02 cells and rats. The data showed that organic extraction from drinking water remarkably impaired rat liver function, evident from the increase in the serum level of alanine aminotransferase, aspartate aminotransferase, and cholinesterase, and decrease in the serum level of total protein and albumin. Organic extraction dose-dependently induced apoptotic cell death in rat liver and L02 cells. Administration of rats with organic extraction promoted death receptor signaling pathway through the increase in gene and protein expression level of Fas and FasL. Treatment of rats with organic extraction also induced mitochondria-mediated apoptosis via increasing the expression level of proapoptotic protein, Bax, but decreasing the expression level of antiapoptotic protein, Bcl-2, resulting in an upregulation of cytochrome c and activation of caspase cascade at both transcriptional and post-transcriptional levels. Moreover, organic extraction enhanced rat liver glutathione S-transferases activity and reactive oxygen species generation, and upregulated aryl hydrocarbon receptor and glutathione S-transferase A1 at both transcriptional and translational levels. Collectively, the results indicate that organic extraction from drinking water impairs liver function, with the involvement of death receptor and mitochondria-mediated apoptosis in rats. The results provide evidence and molecular mechanisms for organic pollutants in drinking water-induced liver dysfunction, which may help prevent and treat organic extraction-induced liver injury.

  9. Therapeutic doses of SkQ1 do not induce cytochromes P450 in rat liver.

    PubMed

    Myasoedova, K N; Silachev, D N

    2014-10-01

    The effect of SkQ1 (a mitochondria-targeted antioxidant) on the level of cytochromes P450 in rat liver was studied. It was found that administration of therapeutic dose of SkQ1 with drinking water for 5 days (250 nmol/kg of body weight per day) did not alter the level of cytochromes P450. Under the same conditions, the standard dose of phenobarbital used for the induction of cytochromes P450 caused the 2.7-fold increase in the content of these cytochromes. We conclude that therapeutic doses of SkQ1 do not induce cytochromes P450 in rats.

  10. 4'-hydroxylation of flurbiprofen by rat liver microsomes in fasting and feeding conditions.

    PubMed

    Shimizu, Makiko; Matsushita, Reiko; Matsumoto, Yoshiaki; Fukuoka, Masamichi

    2003-10-01

    We examined the 4'-hydroxylation of flurbiprofen in rat hepatocytes and liver microsomes in order to know whether the metabolism of flurbiprofen is changed on its administration to experimental animals after overnight fasting, because starvation and fasting change both the composition of cytochrome P450s (CYPs) and metabolic activity. CYPs involved in the hydroxylation were determined by various CYP inhibitors and inhibitory antibodies against rat CYP2C11 and CYP2E1 using the microsomes in fasting and feeding. The results provided a possibiliy that the 4'-hydroxylation might be regulated by CYP2C11, but not by CYP2E1, at fasting rather than feeding.

  11. [Effects of Hemerocallis citrine baroni flavonids on CCl4-induced liver fibrosis of rats].

    PubMed

    Shen, Nan; Huang, Xiao-dong; Li, Zhi-wei; Wang, Yan-chun; Qi, Ling; An, Ying; Liu, Ting-ting

    2015-05-01

    This study is designed to explore the possible effects of Hemerocallis citrina baroni flavonids (HCBF) on liver fibrosis induced by CCl4 in rats. The liver fibrosis model was induced by CCl4, and HCBF were administered by gastric perfusion at 25 and 50 mg x kg(-1) qd for 50 days, while the contents of alanine transaminase (ALT), aspartate aminotransferase (AST), gamma glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), superoxide dismutase (SOD), maleic dialdehyde (MDA) and transforming growth factor-β1 (TGF-β1) were measured and the contents of PINP were measured in liver tissue, and the expression of TGF-β1 were observed by immunohistochemisty and Western blot. The pathological changes of liver tissue were examined by HE. The results showed that HCBF (25, 50 mg x kg(-1)) improved the liver function significantly through reducing the level of ALT, AST, GGT and ALP (P < 0.05 or P < 0.01), and increasing the content of SOD (P < 0.01), while reducing the content of MDA (P < 0.05 or P < 0.01), the expression of TGF-β1 (P < 0.05) and the content of PINP (P < 0.05). The results suggest that HCBF (25, 50 mg x kg(-1)) may inhibit the liver injury induced by CCl4 by decreasing the oxidative stress. PMID:26234134

  12. Ameliorative effects of Moringa oleifera Lam seed extract on liver fibrosis in rats.

    PubMed

    Hamza, Alaaeldin A

    2010-01-01

    This study was carried out to evaluate the effect of Moringa oleifera Lam (Moringa) seed extract on liver fibrosis. Liver fibrosis was induced by the oral administration of 20% carbon tetrachloride (CCl(4)), twice weekly and for 8 weeks. Simultaneously, M.oleifera Lam seed extract (1g/kg) was orally administered daily. The biochemical and histological results showed that Moringa reduced liver damage as well as symptoms of liver fibrosis. The administration of Moringa seed extract decreased the CCl(4)-induced elevation of serum aminotransferase activities and globulin level. The elevations of hepatic hydroxyproline content and myeloperoxidase activity were also reduced by Moringa treatment. Furthermore, the immunohistochemical study showed that Moringa markedly reduced the numbers of smooth muscle alpha-actin-positive cells and the accumulation of collagens I and III in liver. Moringa seed extract showed significant inhibitory effect on 1,1-diphenyl-2-picrylhydrazyl free radical, as well as strong reducing antioxidant power. The activity of superoxide dismutase as well as the content of both malondialdehyde and protein carbonyl, which are oxidative stress markers, were reversed after treatment with Moringa. Finally, these results suggested that Moringa seed extract can act against CCl(4)-induced liver injury and fibrosis in rats by a mechanism related to its antioxidant properties, anti-inflammatory effect and its ability to attenuate the hepatic stellate cells activation. PMID:19854235

  13. Structural differences between liver- and muscle-derived insulin receptors in rats

    SciTech Connect

    Burant, C.F.; Treutelaar, M.K.; Block, N.E.; Buse, M.G.

    1986-11-05

    The structure of insulin receptors, solubilized from rat skeletal muscle and liver, was studied. The ..cap alpha.. subunit was identified by specific cross-linking to A14 /sup 125/I-insulin with disuccinimidyl suberate. Muscle- and liver-derived ..cap alpha.. subunits migrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) with a M/sub r/ of 131,000 and 135,000, respectively. There was no significant difference in insulin binding affinity. Treatment of cross-linked, immunoprecipitated receptors with either neuraminidase or endoglycosidase H decreased the M/sub r/ of muscle- and liver-derived ..cap alpha.. subunits but did not affect the difference in M/sub r/. Autophosphorylated ..beta.. subunits migrated with a M/sub r/ of 98,000 for muscle and 101,000 for liver. After partial V8 digestion of autophosphorylated, immunoprecipitated receptors the major phosphopeptide fragment migrated on SDS-PAGE at M/sub r/ 57,000 from muscle and 60,000 from liver. Glycosidase digestion of autophosphorylated receptors suggested that M/sub r/ heterogeneity was due in part to differences in the sialic acid content of ..beta.. subunits. Muscle and liver are the major target organs of insulin; the apparent heterogeneity of insulin receptor structure may be relevant to tissue-specific differences in insulin action.

  14. Local delivery of vascular endothelial growth factor via nanofiber matrix improves liver regeneration after extensive hepatectomy in rats.

    PubMed

    Yu, Yuan-Quan; Jiang, Xue-Song; Gao, Song; Ma, Rui; Jin, Yun; Jin, Xing; Peng, Shu-You; Mao, Hai-Quan; Li, Jiang-Tao

    2014-11-01

    Vascular endothelial growth factor (VEGF) is a potent regulator for liver regeneration following partial hepatectomy. However, intravenous delivery of VEGF has yielded limited success in promoting the regeneration of remnant liver. Here we report a new approach to locally deliver recombinant VEGF from an electrospun poly-ε-caprolactone nanofiber mesh and its effect on improving rat liver regeneration after 70% hepatectomy. After applying the VEGF-releasing nanofiber mesh to the remnant liver lobes following hepatectomy in rats, the fractions of proliferating hepatocytes increased markedly at 48 h and 72 h in comparison with the control group receiving nanofiber meshes without VEGF. The expression of endogenous VEGF in liver tissue was also higher in the VEGF-nanofiber group than those in the control group. These results demonstrate that biodegradable nanofiber meshes offer a convenient and effective approach for local and sustained delivery of VEGF to the remnant liver following partial hepatectomy.

  15. Vasopressin receptors in the brain, liver and kidney of rats following osmotic stimulation.

    PubMed

    Landgraf, R; Szot, P; Dorsa, D M

    1991-03-29

    The binding site concentration (Bmax) and equilibrium dissociation constant (Kd) for [3H]-arginine vasopressin (AVP) binding sites were measured in limbic brain areas (septum, dorsal hippocampus, amygdala) and liver and kidney of control and osmotically stimulated male Wistar rats. Membrane binding was performed in these five areas 30, 60 and 180 min following intraperitoneal injection of hypertonic saline. This paradigm resulted in no significant change in binding characteristics in the septum, dorsal hippocampus, amygdala and liver from control treated rats. In contrast, the kidney Bmax was significantly reduced 60 min following osmotic stimulation, with no effect on affinity. These results also suggest that AVP receptors in the CNS are relatively resistant to regulatory effects of an acute AVP exposure. PMID:1828184

  16. Inhibition effects of some metal ions on the rat liver 6-phosphogluconate dehydrogenase

    NASA Astrophysics Data System (ADS)

    Adem, Şevki; Kayhan, Naciye

    2016-04-01

    6-phosphogluconate dehydrogenase is an enzyme in the pentose phosphate path. The main functions of the pathway are the manufacture of the reduced coenzyme NADPH and the formation of ribose 5-phosphate for nucleic acid synthesis and nucleotide. Both NADPH and ribose 5-phosphate involve a critical biochemical process. Metals have been recognized as important toxic agents for living for a long time. It has been considered that they lead to in the emergence of many diseases. To evaluate whether metals is effect towards rat liver 6PGD, we apply various concentrations of metals and enzyme inhibition was analyzed using enzyme activity assays. The IC50 values of Pb+2, Cr+3, Co+2, Ni+2, Cd+2, and Va+2, metals on rat liver 6PGD were calculated as 138,138, 169, 214, 280, and 350 µM, respectively.

  17. Biochemical changes in rat liver after 18.5 days of spaceflight (41566)

    NASA Technical Reports Server (NTRS)

    Abraham, S.; Lin, C.Y.; Volkmann, C. M.; Klein, H. P.

    1983-01-01

    The effect of weightlessness on liver metabolism was investigated using tissue from rats flown in earth orbit for 18.5 days on the Soviet Cosmos 936 biosatellite and the changes in the activities of 28 carbohydrate and lipid enzymes were determined. The activities of two enzymes, palmitoyl-CoA desaturase and lactate dehydrogenase, increased, while the activities of five, glycogen phosphorylase, 6-phosphogluconate dehydrogenase, both acyltransferases which act on alpha-glycerolphosphate and diglycerides, and and aconitate hydratase decreased. The other enzyme activities were found to be unchanged. In addition, increased levels of liver glycogen and palmitoleate were detected which probably resulted from the lowered glycogen phosphorylase and increased palmitoyl-CoA desaturase activities, respectively, in those animals that experienced weightlessness. All of the changes observed in the rats after 18.5 days of spaceflight disappear by 25 days after the flight.

  18. Effect of methylmercury on the activity of glutathione peroxidase in rat liver

    SciTech Connect

    Hirota, Y.

    1986-09-01

    The effect of methylmercury on the activity of glutathione peroxidase in rat liver was studied in vivo. A daily dose of 10mg methylmercuric chloride/kg body weight was administered subcutaneously to 15 male Wistar rats for 10 days, and the glutathione peroxidase activity in the liver was measured to compare with the control activity. A marked decrease was observed in the glutathione peroxidase activity in the experimental animals, which measured as low as 40% in comparison to that in the control animals. It can be speculated that the inhibition of glutathione peroxidase activity plays a significant role in the development of mercury toxicity and that the protective effect of selenium and vitamin E on the mercury intoxication might be partly due to preserving the glutathione peroxidase activity in the antioxidative defense mechanisms.

  19. Characterization of a nucleotide stimulated aspartic proteinase in rat liver plasma membranes.

    PubMed

    Paule, C R; Larner, J

    1996-01-01

    Inositol phosphoglycan molecules are believed to mediate multiple intracellular actions of insulin. They are released from plasma membranes in response to insulin binding and are transported into the cell. Release of insulin mediators is stimulated by MnATP and MgATP and is inhibited by p-aminobenzamidine. Inositol phosphoglycan mediators may be released by a poorly characterized mechanism requiring proteolytic cleavage of an attached protein from the mediator and phospholipase cleavage of the mediator from its membrane anchor. We examined rat liver plasma membranes for proteinase activity stimulated by insulin and MnATP. Although we could not demonstrate insulin stimulation, we have found and characterized a nucleotide-stimulated aspartic proteinase bound to rat liver plasma membranes. We also detected and separated a soluble activating factor for the proteinase. The activating factor appears to be a protein with M(r) approximately 70 kDa. PMID:8876431

  20. Participation of cysteine and cystine in inactivation of tyrosine aminotransferase in rat liver homogenates.

    PubMed Central

    Buckley, W T; Milligan, L P

    1978-01-01

    1. Inactivation of tyrosine aminotransferase was studied in rat liver homogenates. Under an O2 atmosphere with cysteine added, inactivation was rapid after a lag period of approx. 1h, whereas a N2 atmosphere extended the lag period to approx. 3h. 2. Replacement of cysteine with cystine resulted in rapid inactivation both aerobically and anaerobically. 3. Removal of the particulate fraction by centrifuging rat liver homogenates at 13,000g for 9min resulted in an aerobic lag period of 0.5h in the presence of cystine and approx. 3h in the presence of cysteine. 4. It is proposed that the stimulatory effect of cysteine on tyrosine aminotransferase inactivation occurs largely as a result of oxidation to cystine, which appears to be a more directly effective agent. PMID:33669

  1. Purification of rat liver arylsulfatase A and its microheterogeneity assayed by crossed affinity-immunoelectrophoresis.

    PubMed

    Wójczyk, B; Hoja, D; Lityńska, A

    1992-01-01

    Arylsulfatase A (arylsulfatase sulfohydrolase) EC 3.1.6.1 was purified from rat liver by a procedure consisting of differential centrifugation, Con A-Sepharose and Blue Sepharose chromatography, PBE 94 chromatofocusing, DEAE-cellulose and gel filtration chromatography followed by preparative electrophoresis. A molecular mass of 132,000 was estimated by gradient PAGE. Particular proteins were detected by immunoelectrophoresis. Isoelectric focusing combined with immunoelectrophoresis gave two peaks of arylsulfatase A, with isoelectric points of pH 3.9 and 4.5. Microheterogeneity of rat liver arylsulfatase A was studied by affinity immunoelectrophoresis with 9 different lectins. The presence of concanavalin A-, Lens culinaris agglutinin-, Lotus tetragonolobus agglutinin- and wheat germ agglutinin-reactive forms permitted assessment of the types of carbohydrate moieties in arylsulfatase A.

  2. Altered carbohydrate, lipid, and xenobiotic metabolism by liver from rats flown on Cosmos 1887

    NASA Technical Reports Server (NTRS)

    Merrill, A. H. Jr; Hoel, M.; Wang, E.; Mullins, R. E.; Hargrove, J. L.; Jones, D. P.; Popova, I. A.; Merrill AH, J. r. (Principal Investigator)

    1990-01-01

    To determine the possible biochemical effects of prolonged weightlessness on liver function, samples of liver from rats that had flown aboard Cosmos 1887 were analyzed for protein, glycogen, and lipids as well as the activities of a number of key enzymes involved in metabolism of these compounds and xenobiotics. Among the parameters measured, the major differences were elevations in the glycogen content and hydroxymethylglutaryl-CoA (HMG-CoA) reductase activities for the rats flown on Cosmos 1887 and decreases in the amount of microsomal cytochrome P-450 and the activities of aniline hydroxylase and ethylmorphine N-demethylase, cytochrome P-450-dependent enzymes. These results support the earlier finding of differences in these parameters and suggest that altered hepatic function could be important during spaceflight and/or the postflight recovery period.

  3. Effects of nonsteroidal anti-inflammatory meloxicam on stomach, kidney, and liver of rats.

    PubMed

    Burukoglu, Dilek; Baycu, Cengiz; Taplamacioglu, Fulya; Sahin, Erhan; Bektur, Ezgi

    2016-06-01

    Nonsteroidal anti-inflammatory (NSAI) drugs are the most commonly used group of drugs today. Increase in the use of standard NSAI for treating pain and inflammation was restricted by the fact that these drugs were proven to possibly cause gastrointestinal and renal toxicity. Meloxicam is a NSAI that has anti-inflammatory, analgesic, and antipyretic effects. This study aims to investigate the effects of meloxicam on stomach, kidney, and liver of rats under light microscopy level. Based on the light microscopic observations, mononuclear cell infiltration and pseudolobular formation was established in liver samples of animals in the experimental group. Metaplasia in surface and glandular epithelia and atrophy were observed in stomach samples. Glomerular stasis-related hypertrophy and focal interstitial nephritis were found in kidneys. It was concluded in this study that meloxicam might cause hepatotoxicity, nephrotoxicity, and gastric metaplasia in rats at a used dose and duration. PMID:24958741

  4. Purification of rat liver arylsulfatase A and its microheterogeneity assayed by crossed affinity-immunoelectrophoresis.

    PubMed

    Wójczyk, B; Hoja, D; Lityńska, A

    1992-01-01

    Arylsulfatase A (arylsulfatase sulfohydrolase) EC 3.1.6.1 was purified from rat liver by a procedure consisting of differential centrifugation, Con A-Sepharose and Blue Sepharose chromatography, PBE 94 chromatofocusing, DEAE-cellulose and gel filtration chromatography followed by preparative electrophoresis. A molecular mass of 132,000 was estimated by gradient PAGE. Particular proteins were detected by immunoelectrophoresis. Isoelectric focusing combined with immunoelectrophoresis gave two peaks of arylsulfatase A, with isoelectric points of pH 3.9 and 4.5. Microheterogeneity of rat liver arylsulfatase A was studied by affinity immunoelectrophoresis with 9 different lectins. The presence of concanavalin A-, Lens culinaris agglutinin-, Lotus tetragonolobus agglutinin- and wheat germ agglutinin-reactive forms permitted assessment of the types of carbohydrate moieties in arylsulfatase A. PMID:1363453

  5. Coffee and caffeine protect against liver injury induced by thioacetamide in male Wistar rats.

    PubMed

    Furtado, Kelly S; Prado, Monize G; Aguiar E Silva, Marco A; Dias, Marcos C; Rivelli, Diogo P; Rodrigues, Maria A M; Barbisan, Luis F

    2012-11-01

    Coffee intake has been inversely related to the incidence of liver diseases, although there are controversies on whether these beneficial effects on human health are because of caffeine or other specific components in this popular beverage. Thus, this study evaluated the protective effects of coffee or caffeine intake on liver injury induced by repeated thioacetamide (TAA) administration in male Wistar rats. Rats were randomized into five groups: one untreated group (G1) and four groups (G2-G5) treated with the hepatotoxicant TAA (200 mg/kg b.w., i.p.) twice a week for 8 weeks. Concomitantly, rats received tap water (G1 and G2), conventional coffee (G3), decaffeinated coffee (G4) or 0.1% caffeine (G5). After 8 weeks of treatment, rats were killed and blood and liver samples were collected. Conventional and decaffeinated coffee and caffeine intake significantly reduced serum levels of alanine aminotransferase (ALT) (p < 0.001) and oxidized glutathione (p < 0.05), fibrosis/inflammation scores (p < 0.001), collagen volume fraction (p < 0.01) and transforming growth factor β-1 (TGF-β1) protein expression (p ≤ 0.001) in the liver from TAA-treated groups. In addition, conventional coffee and caffeine intake significantly reduced proliferating cellular nuclear antigen (PCNA) S-phase indexes (p < 0.001), but only conventional coffee reduced cleaved caspase-3 indexes (p < 0.001), active metalloproteinase 2 (p ≤ 0.004) and the number of glutathione S-transferase placental form (GST-P)-positive preneoplastic lesions (p < 0.05) in the liver from TAA-treated groups. In conclusion, conventional coffee and 0.1% caffeine intake presented better beneficial effects than decaffeinated coffee against liver injury induced by TAA in male Wistar rats. PMID:22646289

  6. Diet high in fructose leads to an overexpression of lipocalin-2 in rat fatty liver

    PubMed Central

    Alwahsh, Salamah Mohammad; Xu, Min; Seyhan, Hatice Ali; Ahmad, Shakil; Mihm, Sabine; Ramadori, Giuliano; Schultze, Frank Christian

    2014-01-01

    AIM: To explore lipocalin-2 (LCN-2) expression and its possible role and mechanism(s) of production in rat models of diet-inducible fatty liver. METHODS: Fatty liver was triggered in male Sprague-Dawley rats fed either with liquid Lieber-DeCarli (LDC) or LDC + 70% cal fructose (L-HFr) diet for 4 or 8 wk. Chow-nourished animals served as controls. Hepatic expression of LCN-2 and other metabolic and inflammatory mediators was assessed by quantitative reverse transcription polymerase chain reaction and Western blotting. Serum LCN-2, fasting leptin, and lipid profile were evaluated via Enzyme-Linked Immunosorbent Assay, Radioimmunoassay, and colorimetric assays, respectively. The localization of LCN-2 in the liver was detected by using immunofluorescence staining. Furthermore, HE stain was used to evaluate hepatic fat degeneration and inflammation. RESULTS: Both LDC-fed and L-HFr-fed rat histologically featured fatty liver. In the liver, mRNA transcriptions of Mcp-1, a2-m, Il-8 and Glut5 were increased in the L-HFr group at both time points (P < 0.001), while the transcription of Tlr4, Inos, and Tnf-α was significantly up-regulated at week 4. Interestingly, hepatic Lcn-2 expression was 90-fold at week 4 and 507-fold at week 8 higher in L-HFr-subjected rats vs control (P < 0.001). In contrast to HDL-cholesterol, systemic levels of LCN-2, fasting leptin and triglycerides were elevated in the L-HFr regimen (P < 0.001). Moreover, protein expression of hepatic LCN-2, CD14, phospho-MAPK, caspase-9, cytochrome c and 4-hydroxynonenal was increased in the L-HFr group. Conversely, the hepatic expression of PGC-1α (a mitochondrial-biogenic protein) was reduced in the L-HFr category at week 8. The localization of LCN-2 in the liver was predominantly restricted to MPO+ granulocytes. CONCLUSION: Fructose diet up-regulates hepatic LCN-2 expression, which correlates with the increased indicators of oxidative stress and mitochondrial dysfunction. The LCN-2 may be involved in liver

  7. Ethinyl estradiol-induced cell proliferation in rat liver. Involvement of specific populations of hepatocytes.

    PubMed

    Mayol, X; Neal, G E; Davies, R; Romero, A; Domingo, J

    1992-12-01

    Hepatocyte proliferation was analyzed in vivo during the time course of continuous administration to rats of the liver tumor promoter ethinyl estradiol (EE) at 10 p.p.m. in the diet. EE-induced acute liver hyperplasia was detected in male and female Sprague-Dawley rats as an increased mitotic index of hepatocytes after 2 days of treatment. 5'-Bromodeoxyuridine (BrdU) labeling showed that proliferating hepatocytes were randomly distributed throughout the hepatic lobule. Subsequently, and still during the first few days of continuous EE treatment, hepatocyte proliferation decreased to control levels, and a transient increase in the incidence of apoptosis in the liver was detected. Although consistent with the concept of liver growth regression after mitogen-induced hyperplasia, these results differ from others reported to date in that, in our experiments, the cessation of cell proliferation and the subsequent growth regression occurred without withdrawal of EE in our experiments. After returning to control levels, hepatocellular proliferation again increased between 3 and 6 months of chronic treatment and remained activated during the following months of continuous treatment, as seen by accumulative BrdU labeling. Proliferating hepatocytes were predominantly located in zone 2 of the hepatic lobule at this time, surrounding a periportal zone of vacuolated hepatocytes, which were also induced by the treatment. Moreover, hyperplasia of basophilic hepatocytes was also seen around some portal spaces. In another set of experiments, chronic EE-induced activation was characterized by flow cytometry on hepatocytes isolated from male Fischer rats. Ploidy analysis of hepatocyte cell suspensions showed that the normal polyploid pattern of hepatocytes was altered by EE, the proportion of diploid hepatocytes rising considerably. The results also showed that these diploid cells were the most susceptible hepatocyte population to EE-induced proliferation, as shown by a combination of

  8. Pegylated Interferon-α Modulates Liver Concentrations of Activin-A and Its Related Proteins in Normal Wistar Rat

    PubMed Central

    Refaat, Bassem; El-Shemi, Adel Galal; Ashshi, Ahmed Mohamed; Mahamid, Elaf Wael; Al-Qadi, Noha Mohammed

    2015-01-01

    Aims. To measure the expression of activin βA-subunit, activin IIA and IIB receptors, Smad4, Smad7, and follistatin in the liver and the liver and serum concentrations of mature activin-A and follistatin in normal rat following treatment with pegylated interferon-α (Peg-INF-α) and ribavirin (RBV). Materials and Methods. 40 male Wistar rats were divided equally into 4 groups: “control,” “Peg-only” receiving 4 injections of Peg-INF-α (6 µg/rat/week), “RBV-only” receiving ribavirin (4 mg/rat/day) orally, and “Peg & RBV” group receiving both drugs. The expression of candidate molecules in liver was measured by immunohistochemistry and quantitative PCR. The concentrations of mature proteins in serum and liver homogenate samples were measured using ELISA. Results. Peg-INF-α  ± RBV altered the expression of all candidate molecules in the liver at the gene and protein levels (P < 0.05) and decreased activin-A and increased follistatin in serum and liver homogenates compared with the other groups (P < 0.05). There were also significant correlations between serum and liver activin-A and follistatin. Conclusion. Peg-INF-α modulates the hepatic production of activin-A and follistatin, which can be detected in serum. Further studies are needed to explore the role of Peg-INF-α on the production of activins and follistatin by the liver and immune cells. PMID:26236109

  9. [Effect of cyanamide on the level of endogenous ethanol in the liver of normal rats and in hypocorticism].

    PubMed

    Tarasov, Iu A; Satanovskaia, V I; Shishkin, S N; Ostrovskiĭ, Iu M

    1988-01-01

    The rat liver endogenous ethanol level was found to increase under inhibition of aldehyde dehydrogenases by cyanamide. Adrenalectomy results in a decrease of the liver endogenous ethanol content and abolishes cyanamide effect on this index. One of the mechanisms of cyanamide toxic effect may be accumulation of different aldehydes including acetaldehyde.

  10. Protective effect of rosuvastatin treatment by regulating oxidized low-density lipoprotein expression in a rat model of liver fibrosis

    PubMed Central

    Yu, Shuiping; Zhou, Xueling; Hou, Bingzong; Tang, Bo; Li, Jian; Zhang, Baimeng

    2016-01-01

    The present study aimed to evaluate the protective effect of rosuvastatin treatment on the mechanism of oxidized low-density lipoprotein (Ox-LDL) in rats with liver fibrosis. In total, 72 male Sprague-Dawley rats were divided into 3 groups: 24 in the control group (A), 24 in the obstructive jaundice models group (B) and 24 in the rosuvastatin group (C). Each group was further divided into four subgroups for assessment at different time-points. The obstructive jaundice models were established and rosuvastatin was administered by gavage. Liver fibrosis indicators, Ox-LDL, malonaldehyde (MDA) and superoxide dismutase (SOD), were measured and liver pathological changes were observed at weeks 1, 2, 3 and 4 after model induction. In groups B and C, the rat models were successfully established, and there were significant changes in the expression of Ox-LDL and the three liver fibrosis indicators when compared to group A (P<0.01). However, the expression of Ox-LDL and the three liver fibrosis indicators in group C were decreased compared with group B (P<0.05), while SOD increased (P<0.05) and MDA decreased (P<0.05). The three liver fibrosis indicators were different in comparison to group B (P<0.05). Thus, there appeared to be an association between the expression of Ox-LDL and liver fibrosis. Treatment with rosuvastatin could regulate the expression of Ox-LDL and improve liver fibrosis in rat models with obstructive jaundice. PMID:27588174

  11. Andrographis paniculata Leaf Extract Prevents Thioacetamide-Induced Liver Cirrhosis in Rats

    PubMed Central

    Bardi, Daleya Abdulaziz; Halabi, Mohammed Farouq; Hassandarvish, Pouya; Rouhollahi, Elham; Paydar, Mohammadjavad; Moghadamtousi, Soheil Zorofchian; Al-Wajeeh, Nahla Saeed; Ablat, Abdulwali; Abdullah, Nor Azizan; Abdulla, Mahmood Ameen

    2014-01-01

    This study investigated the hepatoprotective effects of ethanolic Andrographis paniculata leaf extract (ELAP) on thioacetamide-induced hepatotoxicity in rats. An acute toxicity study proved that ELAP is not toxic in rats. To examine the effects of ELAP in vivo, male Sprague Dawley rats were given intraperitoneal injections of vehicle 10% Tween-20, 5 mL/kg (normal control) or 200 mg/kg TAA thioacetamide (to induce liver cirrhosis) three times per week. Three additional groups were treated with thioacetamide plus daily oral silymarin (50 mg/kg) or ELAP (250 or 500 mg/kg). Liver injury was assessed using biochemical tests, macroscopic and microscopic tissue analysis, histopathology, and immunohistochemistry. In addition, HepG2 and WRL-68 cells were treated in vitro with ELAP fractions to test cytotoxicity. Rats treated with ELAP exhibited significantly lower liver/body weight ratios and smoother, more normal liver surfaces compared with the cirrhosis group. Histopathology using Hematoxylin and Eosin along with Masson’s Trichrome stain showed minimal disruption of hepatic cellular structure, minor fibrotic septa, a low degree of lymphocyte infiltration, and minimal collagen deposition after ELAP treatment. Immunohistochemistry indicated that ELAP induced down regulation of proliferating cell nuclear antigen. Also, hepatic antioxidant enzymes and oxidative stress parameters in ELAP-treated rats were comparable to silymarin-treated rats. ELAP administration reduced levels of altered serum liver biomarkers. ELAP fractions were non-cytotoxic to WRL-68 cells, but possessed anti-proliferative activity on HepG2 cells, which was confirmed by a significant elevation of lactate dehydrogenase, reactive oxygen species, cell membrane permeability, cytochrome c, and caspase-8,-9, and, -3/7 activity in HepG2 cells. A reduction of mitochondrial membrane potential was also detected in ELAP-treated HepG2 cells. The hepatoprotective effect of 500 mg/kg of ELAP is proposed to result

  12. Ultrastructural changes in the parenchymal liver cells of rats treated with high doses of rifampicin.

    PubMed Central

    Piriou, A.; Maissiat, R.; Jacqueson, A.; Warnet, J. M.; Claude, J. R.

    1987-01-01

    Ultrastructural study of hepatic parenchyma was carried out in female Wistar rats after they had received high doses (400 mg X kg-1) of rifampicin for 1, 2, 4, 6 and 8 days. Morphological changes in the endoplasmic reticulum, Golgi apparatus and mitochondria were observed as early as day 1 of intoxication. These changes corroborate the biochemical data available regarding RFP-induced fatty liver. Images Fig. 1 Fig. 2 Fig. 3 & 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 PMID:3580280

  13. [Effect of phytosterols and alkylglycerols in the diet on morphometric indicators of liver structure in rats].

    PubMed

    Gadzhieva, Z M; Kulakova, S N

    2014-01-01

    In the experiment where rats were fed a diet with phytosterols and alkylglycerols for 1,5 months, changes were observed in morphometric parameters in the liver structure in rats. In animals, which were fed a diet with 20% replacement of the fat component (lard) on phytosterols (stanols derived from rapeseed and conifers), blood circulatory disorders of the liver were observed. There was dilatation of the lumens of the central veins and hepatic veins in the interlobular vascular bundles. On the periphery of the lobules, around the vascular bundles, abundant clusters of lymphocytes were revealed. In both groups of rats fed a diet containing various amounts of alkylglycerols obtained from Berrytenthis magister liver (7 and 50 mg per day) and lard as a fat component, in peripheral areas of hepatic lobules the reticuloendothelial cell count was increased as compared with the control group of animals fed a diet containing as fatty component a mixture of lard and sunflower oil (1:1). These cells contained polysaccharides in the cytoplasm and formed thin bands along the hepatic tubules. In addition, in all groups of rats receiving diets with lipid components (both stanols and alkylglycerols), the occurrence of reticuloendothelium proliferation foci in the middle and central zones of liver lobules were 1,8, 2,3 and 2,1 fold higher than in control group. As compared to control animals, the foci in the above groups contained 1,8, 1,7 and 1,6 fold more cells. Furthermore, the number of animals with reticuloendothelium proliferation foci in the groups receiving investigated lipid components was also increased by 2 fold, as compared to controls.

  14. AUTORADIOGRAPHIC ANALYSIS ON AGAR PLATES OF ANTIGENS FROM SUB CELLULAR FRACTIONS OF RAT LIVER SLICES

    PubMed Central

    Morgan, W. S.; Perlmann, P.; Hultin, T.

    1961-01-01

    Slices of rat livers were incubated with 14C amino acids, homogenized, and subjected to differential centrifugation. The microsomes were further extracted with the non-ionic detergent Lubrol W and with EDTA. These extracts and the microsome free "cell sap," freed from the pH 5 precipitable fraction, were subsequently reacted with antisera using agar diffusion techniques. The antisera employed were obtained from rabbits injected with different subcellular fractions of rat liver or with rat serum proteins. When the agar diffusion plates were autoradiographed it was found that some of the precipitates were radioactive while others were not. Control experiments indicated that this labeling was due to the specific incorporation of 14C amino acids into various rat liver antigens during incubation of the slices rather than to a non-specific adsorption of radioactive material to the immunological precipitates. When the slices were incubated with the isotope for up to 30 minutes, the serum proteins which could be extracted from the microsomes with the detergent were strongly labeled, as were a number of additional microsomal antigens of unknown significance. In contrast, the serum proteins present in the cell sap were only weakly labeled. Most of the typical cell sap proteins, both those precipitable and those soluble at pH 5, seemed to remain unlabeled. No consistently reproducible results were obtained with the EDTA extracts of the ribosomal residues remaining after extraction of the microsomes with the detergent. Incubation of the liver slices for longer periods (up to 120 minutes) led to a strong labeling of the serum proteins in the cell sap as well as to the appearance of labeling in additional cell sap proteins. The results are discussed with regard to the subcellular site of synthesis and the metabolism of the different antigens. PMID:13772607

  15. Effects of ovariectomy and resistance training on oxidative stress markers in the rat liver

    PubMed Central

    Rodrigues, Maria Fernanda Cury; Stotzer, Uliana Sbeguen; Domingos, Mateus Moraes; Deminice, Rafael; Shiguemoto, Gilberto Eiji; Tomaz, Luciane Magri; de Sousa, Nuno Manuel Frade; Ferreira, Fabiano Candido; Leite, Richard Diego; Selistre-de-Araújo, Heloisa Sobreiro; Jordão-Júnior, Alceu Afonso; Baldissera, Vilmar; de Andrade Perez, Sérgio Eduardo

    2013-01-01

    OBJECTIVE: The objective of this study was to assess the effects of resistance training on oxidative stress markers in the livers of ovariectomized rats. METHOD: Adult Sprague-Dawley rats were divided into the following four groups (n = 8 per group): sham-operated sedentary, ovariectomized sedentary, sham-operated resistance training, and ovariectomized resistance training. During the resistance training period, the animals climbed a 1.1-m vertical ladder with weights attached to their tails; the sessions were conducted 3 times per week, with 4-9 climbs and 8-12 dynamic movements per climb. The oxidative stress was assessed by measuring the levels of reduced glutathione and oxidized glutathione, the enzymatic activity of catalase and superoxide dismutase, lipid peroxidation, vitamin E concentrations, and the gene expression of glutathione peroxidase. RESULTS: The results showed significant reductions in the reduced glutathione/oxidized glutathione ratio (4.11±0.65 nmol/g tec), vitamin E concentration (55.36±11.11 nmol/g), and gene expression of glutathione peroxidase (0.49±0.16 arbitrary units) in the livers of ovariectomized rats compared with the livers of unovariectomized animals (5.71±0.71 nmol/g tec, 100.14±10.99 nmol/g, and 1.09±0.54 arbitrary units, respectively). Moreover, resistance training for 10 weeks was not able to reduce the oxidative stress in the livers of ovariectomized rats and induced negative changes in the hepatic anti-oxidative/oxidative balance. CONCLUSION: Our findings indicate that the resistance training program used in this study was not able to attenuate the hepatic oxidative damage caused by ovariectomy and increased the hepatic oxidative stress. PMID:24141842

  16. [PROTEIN CONTENT CHANGES IN RATS' LIVER AND BRAIN UNDER CHRONIC ALCOHOL INTOXICATION].

    PubMed

    Raksha, N G; Savchuk, A N; Kharchenko, O I; Galenova, T I; Ostapchenko, L I

    2015-01-01

    An electrophoretic investigation of quantitative protein content in rat's' tissyes under chronic alcoholic intoxication has been done. It was shown the significant increase of protein content with molecular mass 55, 48-50, 43-45, 39-41 KDa and the decrease-of protein fractions with molecular mass 46-48, 34-35, 27-30, 16-18 KDa accordingly in liver and brain homogenates of experimental animals. PMID:26827457

  17. [Effect of phytosterols and alkylglycerols in the diet on morphometric indicators of liver structure in rats].

    PubMed

    Gadzhieva, Z M; Kulakova, S N

    2014-01-01

    In the experiment where rats were fed a diet with phytosterols and alkylglycerols for 1,5 months, changes were observed in morphometric parameters in the liver structure in rats. In animals, which were fed a diet with 20% replacement of the fat component (lard) on phytosterols (stanols derived from rapeseed and conifers), blood circulatory disorders of the liver were observed. There was dilatation of the lumens of the central veins and hepatic veins in the interlobular vascular bundles. On the periphery of the lobules, around the vascular bundles, abundant clusters of lymphocytes were revealed. In both groups of rats fed a diet containing various amounts of alkylglycerols obtained from Berrytenthis magister liver (7 and 50 mg per day) and lard as a fat component, in peripheral areas of hepatic lobules the reticuloendothelial cell count was increased as compared with the control group of animals fed a diet containing as fatty component a mixture of lard and sunflower oil (1:1). These cells contained polysaccharides in the cytoplasm and formed thin bands along the hepatic tubules. In addition, in all groups of rats receiving diets with lipid components (both stanols and alkylglycerols), the occurrence of reticuloendothelium proliferation foci in the middle and central zones of liver lobules were 1,8, 2,3 and 2,1 fold higher than in control group. As compared to control animals, the foci in the above groups contained 1,8, 1,7 and 1,6 fold more cells. Furthermore, the number of animals with reticuloendothelium proliferation foci in the groups receiving investigated lipid components was also increased by 2 fold, as compared to controls. PMID:25059069

  18. Expression of hemopexin in acute rejection of rat liver allograft identified by serum proteomic analysis.

    PubMed

    Xu, Min; Tan, Changjun; Hu, Jinwu; Alwahsh, Salamah Mohammad; Yan, Jun; Hu, Jie; Dai, Zhi; Wang, Zheng; Zhou, Jian; Fan, Jia; Huang, Xiaowu

    2014-07-01

    Acute rejection (AR) and acceptance of allograft after liver transplantation (LTx) remain critical issues that need addressing to improve prognosis. We therefore performed rat orthotopic LTx and proteomic analyses to screen for immune response-related biomarkers in sera. Markers identified were validated at the mRNA and/or protein levels, and the molecules of interest were functionally explored. Compared with syngeneic controls, signs of AR as well as spontaneous acceptance were observed in hematoxylin and eosin-stained sections of liver allografts. In accordance with the severity of AR, 30 protein spots displaying significant changes in abundance were identified using two-dimensional differential gel electrophoresis. Ultimately, 14 serum proteins were sequenced and five spots of interest were identified as hemopexin (HPX). Expression of HPX was significantly and inversely associated with the severity of AR at both the mRNA and protein levels. In vitro, Mt-1, Ho-1, Fth, Ifn-γ, and Il-17 transcripts were significantly upregulated in lysates of lymphocytes stimulated with HPX, whereas Il-10 markedly was remarkably downregulated. Interferon-γ, IL-10, and IL-17 proteins in the supernatant of HPX-stimulated lymphocytes were significantly altered in keeping with the mRNA level. Our data facilitated the generation of a proteomic profile to enhance the understanding of rat liver AR. In view of finding that the HPX serum level is negatively associated with the severity of AR of rat liver allograft, we propose that in vitro treatment with HPX regulates cytokine expression in rat lymphocytes.

  19. Proteomic Analysis of One-carbon Metabolism-related Marker in Liver of Rat Offspring.

    PubMed

    You, Young-Ah; Lee, Ji Hye; Kwon, Eun Jin; Yoo, Jae Young; Kwon, Woo-Sung; Pang, Myung-Geol; Kim, Young Ju

    2015-11-01

    Maternal food intake has a significant effect on the fetal environment, and an inadequate maternal diet may result in intrauterine growth restriction. Intrauterine growth restriction newborn rat pups nursed by normal diet-fed dams exhibited rapid catch-up growth, which plays a critical role in the risk for metabolic and cardiovascular disease in later life. Specifically, one-carbon metabolism in the liver plays a critical role in placental and fetal growth. Impaired functioning of one-carbon metabolism is associated with increased homocysteine levels. In this study, we applied a comprehensive proteomic approach to identify differential expression of proteins related to one-carbon metabolism in the livers of rat offspring as an effect of maternal food restriction during gestation. Data are available via ProteomeXchange with identifier PXD002578. We determined that betaine-homocysteine S-methyltransferase 1, methylenetetrahydrofolate dehydrogenase 1, and ATP synthase subunit beta mitochondrial (ATP5B) expression levels were significantly reduced in the livers of rat offspring exposed to maternal food restriction during gestation compared with in the offspring of rats fed a normal diet (p < 0.05). Moreover, the expression levels of betaine-homocysteine S-methyltransferase 1, methylenetetrahydrofolate dehydrogenase 1, and ATP synthase subunit beta mitochondrial were negatively correlated with serum homocysteine concentration in male offspring exposed to maternal food restriction during gestation and normal diet during lactation. However, in female offspring only expression levels of methylenetetrahydrofolate dehydrogenase 1 were negatively correlated with homocysteine concentration. This study shows that maternal food restriction during late gestation and normal diet during lactation lead to increased homocysteine concentration through disturbance of one-carbon metabolism in the livers of male offspring. This suggests that male offspring have an increased gender

  20. Gossypol ameliorates liver fibrosis in diabetic rats induced by high-fat diet and streptozocin.

    PubMed

    Chen, Guorong; Wang, Rongrong; Chen, Hanbin; Wu, Liang; Ge, Ren-Shan; Wang, Yili

    2016-03-15

    11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) inhibitors have been shown to treat type 2 diabetes (T2D). Since gossypol is an 11β-HSD1 inhibitor, the objective of the present study was to treat T2D and T2D-related liver fibrosis in rat model using low-dose gossypol. T2D was induced by feeding with high fat diet plus injection of streptozocin (30mg/kg). Diabetic rats were treated with either vehicle control or racemic gossypol with a dose of 15mg/kg/day for 4weeks followed by 15mg/kg/week for additional 8weeks. Blood glucose, cholesterol, LDL, and triglycerides were measured. Messenger mRNA levels of glucocorticoid receptor (Nr3c1), phosphoenolpyruvate carboxykinase (Pck1), glucose-6-phosphatase (G6pc), collagen I (Col1a1), collagen III (Col3a1), fibronectin (Fn1), tissue inhibitor of metalloproteinase 1 (Timp1), and 2 (Timp2) were measured. T2D rats had higher serum glucose, cholesterol, LDL, and triglyceride levels compared to control. Liver Nr3c1, Col1a1, Col3a1, Fn1, Timp1, and Timp2 were increased in T2D rats. T2D liver showed significant fibrosis with the increases of α-smooth muscle actin and fibronectin. After gossypol treatment, serum glucose level was lowered by 64%. Liver fibrosis was significantly ameliorated. Nr3c1, Col1a1, Col3a1, Fn1, Timp1, Timp2, Pck1 as well as G6pc levels were significantly reduced. In conclusion, low dose gossypol is effective for the treatment of T2D and T2D-related fibrosis. PMID:26883980

  1. Mercury-selenium interactions in relation to histochemical staining of mercury in the rat liver.

    PubMed

    Baatrup, E; Thorlacius-Ussing, O; Nielsen, H L; Wilsky, K

    1989-02-01

    Selenium has been suggested to enhance the histochemical staining of mercury when sections of tissue are subjected to the silver-enhancement method. In the present study, histochemical staining patterns of mercury in tissue sections of rat livers were compared with the actual content of organic and inorganic Hg in the livers, in both the presence and the absence of Se. Rats were injected intravenously with 5 micrograms of Hg g-1 body weight as methyl [203Hg] mercury chloride (MeHg) or as [203Hg]mercuric chloride (Hg2+). After 2 h, half the rats received an additional intraperitoneal injection of 2 micrograms of Se g-1 body weight as sodium [75Se]selenite. All the rats were killed 1 h later. Homogenized liver samples were prepared for mercury analysis by two different methods: alkaline digestion and ultrasonic disintegration. Quantitative chemical analysis based on benzene extraction of the radioactively labelled Hg compounds showed that the chemical form of mercury, either organic or inorganic, was preserved from its administration to its deposition in the liver. Light and electron microscopy demonstrated that no silver enhancement of Hg occurred when MeHg alone was present in the sections of tissue, whereas MeHg accompanied by Se induced a moderate deposition of silver grains. In contrast, sections containing Hg2+ alone yielded some staining, and the addition of Se increased the staining dramatically. The results of the present study show that acute selenite pretreatment is a prerequisite for the histochemical demonstration of methyl mercury, and greatly increases the staining of inorganic mercury when applying the silver-enhancement method.

  2. Paclitaxel metabolism in rat and human liver microsomes is inhibited by phenolic antioxidants.

    PubMed

    Václavíková, Radka; Horský, Stanislav; Simek, Petr; Gut, Ivan

    2003-09-01

    Paclitaxel is an important, recently introduced anti-neoplastic drug. Paclitaxel metabolites are virtually inactive in comparison with the parent drug. The study investigated whether phenolic antioxidants could inhibit metabolic inactivation sufficiently to increase paclitaxel effects. Cytochrome p450 (CYP)-catalysed metabolism of paclitaxel was investigated in rat and human liver microsomes. In rat microsomes, paclitaxel was metabolised mainly to C3'-hydroxypaclitaxel (C3'-OHP), less to C2-hydroxypaclitaxel (C2-OHP), di-hydroxypaclitaxel (di-OHP) and another monohydroxylated paclitaxel. In human liver microsomes, 6alpha-hydroxypaclitaxel (6alpha-OHP), formed by CYP2C8, was the main metabolite, while C3'-OHP, C2-OHP and another product different from di-OHP were minor metabolites, formed by CYP3A4. In individual human livers 6alpha-OHP was formed at 1.8-fold to 13-fold higher rates than C3'-OHP. Kinetic parameters (K(m) and V(max)) of production of various metabolites in rat and human liver microsomes revealed differences between species as well as human individual differences. Nine phenolic antioxidants ((+)-catechin, (-)-epicatechin, fisetin, gallic acid, morin, myricetin, naringenin, quercetin and resveratrol) were tested for inhibition of paclitaxel metabolism. In rat microsomes, resveratrol was more inhibitory than fisetin; the other phenolic antioxidants were without effect. In human microsomes, the inhibiting potency decreased in the order fisetin >quercetin >morin >resveratrol, while the other phenolic antioxidants were not inhibitory; the formation of 6alpha-OHP (CYP2C8) was generally more inhibited than that of C3'-OHP. The inhibition was mostly mixed-type. The results suggest that oral administration of some phenolic substances might increase paclitaxel blood concentrations during chemotherapy.

  3. The influence of oxygen tension on theophylline clearance in the rat isolated perfused liver.

    PubMed

    Miller, R; Oliver, I F

    1986-03-01

    The effect of changes in the rate of perfusion and oxygen tension (PO2) on theophylline clearance was determined in the rat isolated perfused liver. Changes in rate of perfusion had no effect on the extraction ratio of theophylline while a decrease in the PO2 significantly increased the half life of theophylline. These results suggest that changes in PO2 whether due to disease states or oxygen administration may necessitate theophylline dosage adjustment.

  4. Effect of hydroalcoholic extract of ginger on the liver of epileptic female rats treated with lamotrigine

    PubMed Central

    Poorrostami, Ameneh; Farokhi, Farah; Heidari, Reza

    2014-01-01

    Objective: Lamotrigine is an antiepileptic drug, widely used in the treatment of epilepsy; long-term use of this drug can cause hepatotoxicity. Zingiber officinale Roscoe (ginger) possesses antioxidant properties. In present research, the effect ofhydroalcoholic extract of ginger (HEG) on the liver of lamotrigine-treated epileptic rats was investigated Material and Methods: Forty-eight female Wistar rats were selected and allocated to 8 groups of 6 each. Group 1: Negative controls were treated with normal saline. Group 2: Positive controls were treated with lamotrigine (LTG) (10 mg/kg) daily by gavages for 4 consecutive weeks. Epilepsy was induced in treatment groups by i.p. injection of pentylenetetrazol (PTZ) (40 mg/kg). Group 3: Epileptic group received normal saline (10 ml/kg). Group 4: Epileptic group was treated with LTG (10 mg/kg). Groups 5 and 6: Epileptic groups received HEG (50 and 100 mg/kg). Groups 7 and 8: Epileptic groups received LTG and HEG (50 and 100 mg/kg). At the end of 28 days, blood samples were drawn and their livers were processed for light microscopy. Results: The mean values of TG, CHOL, AST, and ALT activity significantly rose (p<0.01) in groups 2, 3, and 4, while in rats treated with HEG (groups 5, 6, 7, and 8), the levels of liver enzymes significantly decreased (p<0.05) compared with epileptic group treated with lamotrigine (group 4). Histopathological changes of liver samples were comparable with respective control. Conclusion: These results suggest that hydroalcoholic extract of ginger improves liver function in lamotrigine-induced hepatotoxicity. PMID:25068142

  5. A potential experimental model for the study of osteopenia in CCl4 liver cirrhotic rats.

    PubMed

    Muguerza, B; Lecároz, C; Picardi, A; Castilla-Cortázar, I; Quiroga, J; Cemborain, A; Prieto, J; Santidrián, S

    1996-06-01

    In order to search for an experimental model to further investigate the osteopenia associated to liver cirrhosis (LC), this study has been focused on investigating the occurrence of bone disorders in male rats to which LC histologically confirmed was induced through the validated procedure of CCl4 inhalation. Length, anteroposterior and lateromedial diameters, densitometry, mechanical stress resistance, hydroxyproline (OHprol) and calcium and phosphate contents were measured in femurs from control (n = 10) and liver cirrhosis rats (n = 10). It has been found that femurs from liver cirrhosis rats showed a significant reduction (p < 0.01) in bone weight (0.254 +/- 0.003 vs 0.230 +/- 0.004 g/100 g b.w.), anteroposterior (4.08 +/- 0.06 vs 3.69 +/- 0.05 mm) and lateromedial (5.33 +/- 0.05 vs 5.08 +/- 0.04 mm, p < 0.05) diameters, resistance to mechanical stress (405.8 +/- 9.5 vs 332.5 +/- 9.1 N) and total densitometry (0.416 +/- 0.005 vs 0.381 +/- 0.004 g/cm2). However, no significant differences were observed in bone length, calcium, OHprol and phosphate (all expressed as mg/100 mg fresh bone tissue) contents. Therefore, the proteins matrix to mineral contents ratio was not altered. These results indicate that in this model of experimental liver cirrhosis there is osteopenia characterized by bone frailty and reduced thickness, and it could offer an experimental model to study bone changes associated to liver cirrhosis. PMID:8870109

  6. Coffee enhances the expression of chaperones and antioxidant proteins in rats with nonalcoholic fatty liver disease.

    PubMed

    Salomone, Federico; Li Volti, Giovanni; Vitaglione, Paola; Morisco, Filomena; Fogliano, Vincenzo; Zappalà, Agata; Palmigiano, Angelo; Garozzo, Domenico; Caporaso, Nicola; D'Argenio, Giuseppe; Galvano, Fabio

    2014-06-01

    Coffee consumption is inversely related to the degree of liver injury in patients with nonalcoholic fatty liver disease (NAFLD). Molecular mediators contributing to coffee's beneficial effects in NAFLD remain to be elucidated. In this study, we administrated decaffeinated espresso coffee or vehicle to rats fed an high-fat diet (HFD) for 12 weeks and examined the effects of coffee on liver injury by using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) proteomic analysis combined with mass spectrometry. Rats fed an HFD and water developed panacinar steatosis, lobular inflammation, and mild fibrosis, whereas rats fed an HFD and coffee exhibited only mild steatosis. Coffee consumption increased liver expression of the endoplasmic reticulum chaperones glucose-related protein 78 and protein disulfide-isomerase A3; similarly, coffee drinking enhanced the expression of the mitochondrial chaperones heat stress protein 70 and DJ-1. Furthermore, in agreement with reduced hepatic levels of 8-isoprostanes and 8-hydroxy-2'-deoxyguanosine, proteomic analysis showed that coffee consumption induces the expression of master regulators of redox status (i.e., peroxiredoxin 1, glutathione S-transferase α2, and D-dopachrome tautomerase). Last, proteomics revealed an association of coffee intake with decreased expression of electron transfer flavoprotein subunit α, a component of the mitochondrial respiratory chain, involved in de novo lipogenesis. In this study, we were able to identify by proteomic analysis the stress proteins mediating the antioxidant effects of coffee; moreover, we establish for the first time the contribution of specific coffee-induced endoplasmic reticulum and mitochondrial chaperones ensuring correct protein folding and degradation in the liver. PMID:24365744

  7. The effect of antifibrotic drugs in rat precision-cut fibrotic liver slices.

    PubMed

    Westra, Inge M; Oosterhuis, Dorenda; Groothuis, Geny M M; Olinga, Peter

    2014-01-01

    Two important signaling pathways in liver fibrosis are the PDGF- and TGFβ pathway and compounds inhibiting these pathways are currently developed as antifibrotic drugs. Testing antifibrotic drugs requires large numbers of animal experiments with high discomfort. Therefore, a method to study these drugs ex vivo was developed using precision-cut liver slices from fibrotic rat livers (fPCLS), representing an ex vivo model with a multicellular fibrotic environment. We characterized the fibrotic process in fPCLS from rat livers after 3 weeks of bile duct ligation (BDL) during incubation and tested compounds predominantly inhibiting the TGFβ pathway (perindopril, valproic acid, rosmarinic acid, tetrandrine and pirfenidone) and PDGF pathway (imatinib, sorafenib and sunitinib). Gene expression of heat shock protein 47 (Hsp47), α smooth muscle actin (αSma) and pro-collagen 1A1 (Pcol1A1) and protein expression of collagens were determined. During 48 hours of incubation, the fibrosis process continued in control fPCLS as judged by the increased gene expression of the three fibrosis markers, and the protein expression of collagen 1, mature fibrillar collagen and total collagen. Most PDGF-inhibitors and TGFβ-inhibitors significantly inhibited the increase in gene expression of Hsp47, αSma and Pcol1A1. Protein expression of collagen 1 was significantly reduced by all PDGF-inhibitors and TGFβ-inhibitors, while total collagen was decreased by rosmarinic acid and tetrandrine only. However, fibrillar collagen expression was not changed by any of the drugs. In conclusion, rat fPCLS can be used as a functional ex vivo model of established liver fibrosis to test antifibrotic compounds inhibiting the PDGF- and TGFβ signalling pathway. PMID:24755660

  8. A potential experimental model for the study of osteopenia in CCl4 liver cirrhotic rats.

    PubMed

    Muguerza, B; Lecároz, C; Picardi, A; Castilla-Cortázar, I; Quiroga, J; Cemborain, A; Prieto, J; Santidrián, S

    1996-06-01

    In order to search for an experimental model to further investigate the osteopenia associated to liver cirrhosis (LC), this study has been focused on investigating the occurrence of bone disorders in male rats to which LC histologically confirmed was induced through the validated procedure of CCl4 inhalation. Length, anteroposterior and lateromedial diameters, densitometry, mechanical stress resistance, hydroxyproline (OHprol) and calcium and phosphate contents were measured in femurs from control (n = 10) and liver cirrhosis rats (n = 10). It has been found that femurs from liver cirrhosis rats showed a significant reduction (p < 0.01) in bone weight (0.254 +/- 0.003 vs 0.230 +/- 0.004 g/100 g b.w.), anteroposterior (4.08 +/- 0.06 vs 3.69 +/- 0.05 mm) and lateromedial (5.33 +/- 0.05 vs 5.08 +/- 0.04 mm, p < 0.05) diameters, resistance to mechanical stress (405.8 +/- 9.5 vs 332.5 +/- 9.1 N) and total densitometry (0.416 +/- 0.005 vs 0.381 +/- 0.004 g/cm2). However, no significant differences were observed in bone length, calcium, OHprol and phosphate (all expressed as mg/100 mg fresh bone tissue) contents. Therefore, the proteins matrix to mineral contents ratio was not altered. These results indicate that in this model of experimental liver cirrhosis there is osteopenia characterized by bone frailty and reduced thickness, and it could offer an experimental model to study bone changes associated to liver cirrhosis.

  9. Acute lethal graft-versus-host disease stimulates cellular proliferation in the adult rat liver.

    PubMed

    Klein, R M; Clancy, J; Stuart, S

    1982-11-01

    The present investigation was designed to analyse the effects of acute lethal graft-versus-host disease (GVHD) in adult (DA x LEW)F1 rats on cellular proliferation within the liver. The influence of the host thymus on GVHD-induced proliferation was also assessed. From 1-28 days after initiation of GVHD [3H]thymidine ([3H]-TdR) was injected i.v. and rats were killed one hour later. Percentage labelled cells (LI) of periportal infiltrating cells (PIC), hepatocytes (H), and sinusoidal lining cells (SC) were counted. Mean values for control rats were 0.3 +/- 0.1% (H), 0.4 +/- 0.1% (SC) and 0.2 +/- 0.1% (PIC). GVHD rats demonstrated a significant increase in LI of PIC (days 1-21), SC (days 2-17) and H (days 2-17). Most labelled cells in PIC were large lymphocytes. Peak LI values were 7.0 +/- 1.0% PIC (day 17), 6.8 +/- 0.9% SC (day 17), and 5.2 +/- 0.9% H (day 7), with all cellular compartments returning to near normal LI values by day 28. Stimulation of cellular proliferation occurred in all three liver cell compartments in neonatally thymectomized (TXM) rats. The intensity of GVHD-induced cell proliferation was significantly decreased at day 7 in all compartments and PIC was dramatically decreased at day 21 in TXM-GVHD rats as compared to non-TXM-GVHD rats. It is hypothesized that the general stimulation of hepatocyte cell proliferation in GVHD is related to the secretion of lymphokines by primarily donor and secondarily host T cells in the periportal infiltrate. PMID:7172201

  10. Hepatoprotective potential of zingerone against nonalcoholic fatty liver disease in rats fed with fructose-enriched diet.

    PubMed

    Muniandy Narayanan, Jeyabarathy; Jesudoss, Victor A S

    2016-04-01

    Overconsumption of fructose increases the risk of nonalcoholic fatty liver disease (NAFLD), obesity and metabolic syndrome. NAFLD is currently one of the most common etiologies of chronic liver disease worldwide. The aim of the present study is to evaluate the hepatoprotective potential of zingerone against fructose-enriched diet-induced rat model of nonalcoholic fatty liver disease. Male albino Wistar rats were used and randomly divided into four groups: group 1, control rats fed with standard pellet; group 2, rats were fed normal pellet with intragastric intubation of zingerone (100 mg/kg/day); group 3, rats were fed fructose enriched diet alone; group 4, rats were fed fructose enriched diet with intragastric intubation of zingerone (100 mg/kg/day). Body weight, abdominal circumference, blood glucose, lipid profile and hepatic function indicators were increased and HDL reduced in group 3 rats. Liver pathology of group 3 showed marked changes which includes micro- and macrovesicular steatosis, marked inflammatory cell infiltration, sinusoidal fibrosis and with a significant increase in the area percentage of the collagen. Administration of zingerone reversed the fructose enriched diet induced changes especially body weight, abdominal circumference, blood glucose, lipid profile, hepatic function indicators and restored pathological alteration of liver. Taken together these data provide new insights into the preventive approach of zingerone against the development of the NAFLD.

  11. Hepatoprotective potential of zingerone against nonalcoholic fatty liver disease in rats fed with fructose-enriched diet.

    PubMed

    Muniandy Narayanan, Jeyabarathy; Jesudoss, Victor A S

    2016-04-01

    Overconsumption of fructose increases the risk of nonalcoholic fatty liver disease (NAFLD), obesity and metabolic syndrome. NAFLD is currently one of the most common etiologies of chronic liver disease worldwide. The aim of the present study is to evaluate the hepatoprotective potential of zingerone against fructose-enriched diet-induced rat model of nonalcoholic fatty liver disease. Male albino Wistar rats were used and randomly divided into four groups: group 1, control rats fed with standard pellet; group 2, rats were fed normal pellet with intragastric intubation of zingerone (100 mg/kg/day); group 3, rats were fed fructose enriched diet alone; group 4, rats were fed fructose enriched diet with intragastric intubation of zingerone (100 mg/kg/day). Body weight, abdominal circumference, blood glucose, lipid profile and hepatic function indicators were increased and HDL reduced in group 3 rats. Liver pathology of group 3 showed marked changes which includes micro- and macrovesicular steatosis, marked inflammatory cell infiltration, sinusoidal fibrosis and with a significant increase in the area percentage of the collagen. Administration of zingerone reversed the fructose enriched diet induced changes especially body weight, abdominal circumference, blood glucose, lipid profile, hepatic function indicators and restored pathological alteration of liver. Taken together these data provide new insights into the preventive approach of zingerone against the development of the NAFLD. PMID:26915720

  12. Effect of n-propylthiouracil or thyroxine on arsenic trioxide toxicity in the liver of rat.

    PubMed

    Allen, Tanu; Rana, Suresh Vir Singh

    2007-01-01

    Involvement of thyroid gland in the hepatotoxic manifestations of arsenic trioxide (As(III)) has been studied in rat. The effects of n-propylthiouracil (PTU) (a thyrotoxic compound) and L-thyroxine (a thyroid hormone) have been studied with reference to T(3) and T(4) values in the serum, arsenic concentration in the liver, Ca(2+) accumulation in the liver, aspartate transaminase, alanine transaminase and bilirubin values as the indicators of liver function, histopathological observations and finally the ultrastructural studies. It is concluded that hypothyroid condition protects against As(III) toxicity. Scavenging of reactive oxygen species (ROS) that significantly contribute in As(III) toxicity, by high intracellular concentration of reduced glutathione, as a consequence of PTU treatment is proposed as the plausible protective mechanism.

  13. Suppression of liver Apo E secretion leads to HDL/cholesterol immaturity in rats administered ethinylestradiol.

    PubMed

    Yamaguchi, Kosuke; Ishii, Mariko; Maeda, Naoyuki; Iwano, Hidetomo; Yokota, Hiroshi

    2016-09-01

    Ethinylestradiol (EE), a main component of the combined oral contraceptive pill, is associated with an increased risk of arterial diseases. However, the toxicity mechanism of EE is poorly understood. In this study, we found that the exposure to EE reduced the serum apolipoprotein E (Apo E) level and high-density lipoprotein (HDL)/cholesterol concentration in adult female rats. Diethylstilbestrol showed the same effects and both reductions were suppressed by coadministration of tamoxifen (TAM). Liver perfusion experiments revealed that the secretion rate of Apo E from the liver was significantly reduced. It is concluded that EE damages the maturation of HDL/cholesterol by delaying Apo E secretion from the liver, and this may lead to an increased risk of arterial diseases, such as atheromas. PMID:27642556

  14. Hepatoprotective activity of Moringa oleifera on antitubercular drug-induced liver damage in rats.

    PubMed

    Pari, L; Kumar, N Ashok

    2002-01-01

    Moringa oleifera Lam (Moringaceae), commonly known as "Drumstick," is used in Indian folk medicine for the treatment of various illness. We have evaluated the hepatoprotective effect of an ethanolic extract of M. oleifera leaves on liver damage induced by antitubercular drugs such as isoniazid (INH), rifampicin (RMP), and pyrazinamide (PZA) in rats. Oral administration of the extract showed a significant protective action made evident by its effect on the levels of glutamic oxaloacetic transaminase (aspartate aminotransferase), glutamic pyruvic transaminase (alanine aminotransferase), alkaline phosphatase, and bilirubin in the serum; lipids, and lipid peroxidation levels in liver. This observation was supplemented by histopathological examination of liver sections. The results of this study showed that treatment with M. oleifera extracts or silymarin (as a reference) appears to enhance the recovery from hepatic damage induced by antitubercular drugs. PMID:12495589

  15. Specific regulation of male rat liver cytosolic estrogen receptor by the modulator of the glucocorticoid receptor.

    PubMed

    Celiker, M Y; Haas, A; Saunders, D; Litwack, G

    1993-08-31

    Modulator is a novel low-molecular-weight organic compound that regulates activities of glucocorticoid and mineralocorticoid receptors as well as protein kinase C. In this study we show that male rat liver cytosolic estrogen receptor activation is inhibited by modulator in a dose-dependent manner. Fifty percent inhibition is obtained with 1 unit/ml modulator purified from bovine liver which is within the physiological concentration for modulator. However, sheep uterine cytosolic estrogen and androgen receptors are insensitive to regulation by modulator. Exogenous sodium molybdate treatment inhibits activation of all of these receptors of liver or uterus origin in an identical manner, further differentiating the effects of modulator and the molybdate anion. PMID:8363596

  16. Liver irradiation causes distal bystander effects in the rat brain and affects animal behaviour

    PubMed Central

    Kovalchuk, Anna; Mychasiuk, Richelle; Muhammad, Arif; Hossain, Shakhawat; Ilnytskyy, Slava; Ghose, Abhijit; Kirkby, Charles; Ghasroddashti, Esmaeel; Kovalchuk, Olga; Kolb, Bryan

    2016-01-01

    Radiation therapy can not only produce effects on targeted organs, but can also influence shielded bystander organs, such as the brain in targeted liver irradiation. The brain is sensitive to radiation exposure, and irradiation causes significant neuro-cognitive deficits, including deficits in attention, concentration, memory, and executive and visuospatial functions. The mechanisms of their occurrence are not understood, although they may be related to the bystander effects. We analyzed the induction, mechanisms, and behavioural repercussions of bystander effects in the brain upon liver irradiation in a well-established rat model. Here, we show for the first time that bystander effects occur in the prefrontal cortex and hippocampus regions upon liver irradiation, where they manifest as altered gene expression and somewhat increased levels of γH2AX. We also report that bystander effects in the brain are associated with neuroanatomical and behavioural changes, and are more pronounced in females than in males. PMID:26678032