Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019209 (hepatomegaly)
5,798 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present study was conducted to determine the dermal toxicity of coal coprocessing products and to assess their potential health hazards. Groups of 10 male and 10 female Sprague-Dawley rats were administered dermally coal coprocessing products (light gas oil, LGO; heavy gas oil I, HGOI; heavy gas oil II, HGOII) at 1 g/kg body weight/d for 14 d. The control and positive control groups received normal saline and a coal liquefaction product (CLP) at the same dose level, respectively. Treatment with either the three fractions of coprocessing products or CLP caused decreased growth rate and food consumption in animals of both sexes. Liver enlargement occurred in groups treated with HGOI, HGOII, and CLP. Decreased serum glucose was observed in animals of both sexes treated with the three fractions and CLP. Treatment with HGOI and CLP caused an elevation of hepatic microsomal ethoxyresorufin deethylase activity in the rat of both sexes. The three fractions and CLP caused mild anemia. Mild treatment-related histological changes were observed in the liver, spleen, thyroid, bone marrow, and kidney. All three fractions of coprocessing products were tested for their mutagenicity in five strains of Salmonella typhimurium: TA98, TA100, TA1535, TA1537, and TA1538. HGOI, after metabolic activation, was found to be mutagenic in the strains of TA98, TA100, and TA1538. In contrast, HGOII was mutagenic in the five strains with or without metabolic activation. These data indicate that HGOI and HGOII are more toxic than LGO, and should be subjected to further studies to determine their long-term effects.
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PMID:Short-term dermal toxicity and mutagenicity of coal coprocessing products in the rat. 185 79

Chronic ciprofibrate administration resulted in distinct differences in hepatic responses between the two species examined. In the rat, hepatomegaly was observed with the coordinate induction of carnitine acetyltransferase, peroxisomal beta-oxidation and cytochrome P450IVA1 activities. The latter induction of cytochrome P450IVA1-dependent fatty acid hydroxylase activity was specific to this cytochrome P450 sub family, as ciprofibrate pretreatment resulted in an inhibition of the enzyme activities associated with the cytochrome P450 IIB and IA sub-families. Induction of mitochondrial enzymes were also noted in the rat, but at a substantially lower level than the microsomal and peroxisomal enzyme changes noted above. The majority of these enzyme changes were reversible in the rat after a 4-week, inducer-free period. In contrast, the marmoset displayed a different pattern of enzyme changes in response to ciprofibrate and at the high dose level, inhibition of microsomal fatty acid hydroxylase activity was observed in addition to no change in carnitine acetyltransferase activity. Although peroxisomal beta-oxidation activity was induced in the marmoset, the specific activity was 10-fold lower than in the rat, concomitant with only minimum changes in the liver: body weight ratio. Taken collectively, our data have demonstrated that the marmoset is relatively refractory to ciprofibrate-induced liver enzyme changes with the implication that the extrapolation of the associated hepatotoxicity clearly documented in rodents must be viewed with extreme caution in non-human primates.
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PMID:Comparative induction of cytochrome P450IVA1 and peroxisome proliferation by ciprofibrate in the rat and marmoset. 190 30

This study investigated the ability of HCB (0.1% in the diet for 15 days) to cause early changes in the cellular ploidy of rat liver. Treatment caused marked hepatomegaly, increase of microsomal proteins and cytochrome P-450 content and reduction of hepatocyte microviscosity. Microscopic examination showed that the hepatocytes were enlarged, with hyaline cytoplasm and vacuoles. The size distribution of the isolated hepatocytes showed a larger percentage of bigger cells. Flow-cytometric DNA/protein analysis was performed on whole (fixed) cells and on nuclei. From the combined results of both analyses it was possible to exclude significant changes in the percentage sof diploid, mononucleated tetraploid, binucleated tetraploid and octoploid hepatocytes. The DNA and protein content of each subpopulation remained unchanged. Our results suggest that HCB does not cause early diploidization of liver cells and that hepatomegaly and cytochrome P-450 induction seem not to be correlated with effects on total DNA and total protein contents.
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PMID:Biochemical, morphological and flow-cytometric evaluation of the effects of hexachlorobenzene on rat liver. 236 Nov 91

The influence of ciprofibrate, a potent oxyisobutyrate derivative, on several hepatic enzyme parameters was studied in five rat strains following a 14-day treatment period. Ciprofibrate-dependent hepatomegaly was observed at two dose levels (2 and 20 mg/kg) in all rat strains examined. A 10- to 15-fold induction in the 12-hydroxylation of lauric acid with a less marked 1.5- to 5-fold induction of 11-hydroxylation was observed in treated animals. This dose-dependent increase in fatty acid hydroxylase activity was associated with a maximal 10-fold increase in the specific content of cytochrome P-450 IVA1 isoenzyme apoprotein, as assessed immunochemically using an ELISA technique. The activities of the cytochrome P-450 I (IA1 and IA2) and II (IIB1 and IIB2) families, as measured by ethoxyresorufin-O-deethylase and benzphetamine-N-demethylase activities respectively, were decreased on treatment. In the mitochondria, monoamine oxidase activity was significantly decreased at the higher dose level whereas alpha-glycerophosphate dehydrogenase activity was elevated. Total carnitine acetyltransferase activity (mitochondrial and peroxisomal) and peroxisomal beta-oxidation were markedly increased at both dose levels in all strains examined. Cytosolic glutathione peroxidase activity, measured using both t-butylhydroperoxide and hydrogen peroxide as substrates, was decreased on treatment to approximately 50% of the control value. In treated animals, a marked increase in mRNA levels coding for cytochrome P-450 IVA1 and the peroxisomal bifunctional protein of the fatty acid beta-oxidation spiral was observed. However, mRNA levels coding for glutathione peroxidase appeared unchanged following ciprofibrate administration, in contrast to the above-noted decrease of glutathione peroxidase enzyme activity. Taken collectively, our results have further substantiated a close association between the induction of microsomal cytochrome P-450 IVA1, peroxisomal beta-oxidation and total carnitine acetyltransferase activity in rat liver, and have performed a conceptual basis for the rationalization of the chronic toxicity of peroxisome proliferators in this species.
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PMID:Characterization of the hepatic responses to the short-term administration of ciprofibrate in several rat strain. Co-induction of microsomal cytochrome P-450 IVA1 and peroxisome proliferation. 239 Jan 5

We have examined, relative to clofibric acid (CPIB), the effects of a chemical series of phenoxyacetic acids and of two asymmetric CPIB analogues, the R(+)- and S(-)-enantiomers of 2-(4-chlorophenoxy)propionic acid (4-CPPA) and 2-(4-chlorophenoxy)butyric acid (4-CPBA), on hepatic peroxisome proliferation both in vivo and in vitro utilizing cholesterol-fed rats and primary cultured rat hepatocytes respectively. Peroxisome proliferation was assessed by measuring changes in peroxisomal fatty acyl-CoA oxidase (FACO) and microsomal laurate hydroxylase (LH) activities as well as by electron microscopic examination of 3,3'-diaminobenzidine-stained liver slices. CPIB and enantiomers of 4-CPPA and 4-CPBA (0.6 mmol/kg/day for 7 days) produced hepatomegaly, lowered serum cholesterol levels, and caused 4.7- to 12.9-fold and 2.9- to 6.1-fold increases in hepatic FACO and LH activities, respectively, in cholesterol-fed rats. Electron micrographs of liver cells showed an increased number of peroxisomes from cholesterol-fed rats given S(-)-4-CPBA and CPIB. Likewise, these compounds (0.03 to 1.0 mM) induced FACO and LH in primary rat hepatocyte cultures after 72 hr. R(+)- and S(-)-Enantiomers of 4-CPPA produced similar concentration-dependent and maximal increases in both FACO and LH activities, whereas enantiomeric selectivity [S(-) greater than R(+)] for the induction of these two enzymes was observed with the isomers of 4-CPBA. The increases in the activities of FACO and LH caused by S(-)-4-CPBA were similar to those elicited by 1.0 mM CPIB (58.6- and 9.8-fold respectively). These results show that the enantiomers of 4-CPPA and 4-CPBA induce the peroxisome proliferation-associated enzymes FACO and LH in vivo and in vitro, and that the S(-)-isomer of 4-CPBA causes a greater induction of FACO and LH in vitro than its corresponding R(+)-isomer, indicating that these two enzymes are induced in an enantioselective manner. Optimal induction of the peroxisome proliferation-associated enzymes FACO and LH in rat hepatocyte cultures was produced by phenoxyacetic acids possessing (1) a chlorine atom at the 4-position of the phenyl ring, (2) a dimethyl or mono-ethyl substitution at the alpha-carbon atom of the carboxylic acid side chain; and (3) an S(-)-orientation for chiral analogues possessing a mono-ethyl group at the alpha-carbon atom of the carboxylic acid side chain.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:In vivo and in vitro peroxisome proliferation properties of selected clofibrate analogues in the rat. Structure-activity relationships. 240 80

Inductions by perfluoro-octanoic acid (PFOA) of hepatomegaly, peroxisomal beta-oxidation, microsomal 1-acylglycerophosphocholine acyltransferase and cytosolic long-chain acyl-CoA hydrolase were compared in liver between male and female rats. Marked inductions of these four parameters were seen concurrently in liver of male rats, whereas the inductions in liver of female rats were far less pronounced. The sex-related difference in the response of rat liver to PFOA was much more marked than that seen with p-chlorophenoxyisobutyric acid (clofibric acid) or 2,2'-(decamethylenedithio)diethanol (tiadenol). Hormonal manipulations revealed that this sex-related difference in the inductions is strongly dependent on sex hormones, namely that testosterone is necessary for the inductions, whereas oestradiol prevented the inductions by PFOA.
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PMID:Sex-related difference in the inductions by perfluoro-octanoic acid of peroxisomal beta-oxidation, microsomal 1-acylglycerophosphocholine acyltransferase and cytosolic long-chain acyl-CoA hydrolase in rat liver. 257 May 71

The activity of key enzymes involved in oxidation and esterification of long-chain fatty acids was investigated after male Wistar rats were treated with different doses of sulfur substituted fatty acid analogues, 1,10-bis(carboxymethylthiodecane) (BCMTD, non-beta-oxidizable and non-omega-oxidizable), 1-mono(carboxymethylthiotetradecane) (CMTTD, trivial name, alkylthio acetic acid, non-beta-oxidizable) and 1-mono(carboxyethylthiotetradecane) (CETTD trivial name, alkylthio propionic acid, beta-oxidizable). The sulfur substituted dicarboxylic acid and the alkylthio acetic acid induced in a dose-dependent manner the mitochondrial, microsomal and especially the peroxisomal palmitoyl-CoA synthetase activity, the mitochondrial and cytosolic palmitoyl-CoA hydrolase activity, the mitochondrial and especially the microsomal glycerophosphate acyltransferase activity and the peroxisomal beta-oxidation, especially revealed in the microsomal fraction. Morphometric analysis of randomly selected hepatocytes revealed that BCMTD and CMTTD treatment increased the number, size and volume fraction of peroxisomes and mitochondria. Thus, the observed changes in the specific activity of fatty acid metabolizing enzymes with multiple subcellular localization can partly be explained as an effect of changes in the s-values of the organelles as proliferation of mitochondria and peroxisomes occurred. The most striking effect of the alkylthio propionic acid was the formation of numerous fat droplets in the liver cells and enhancement of the hepatic triglyceride level. This was in contrast to BCMTD treatment which decreased the hepatic triglyceride content. In conclusion, the results provide evidence that administration of non-beta-oxidizable fatty acid analogues had much higher in vivo potency in inducing hepatomegaly and key enzymes involved in fatty acid metabolism, including proliferation of peroxisomes and mitochondria than is exhibited in the beta-oxidizable, alkylthio propionic acid. Moreover, the dicarboxylic acid was apparently three to six times more potent than the alkylthio acetic acid in inducing peroxisomal beta-oxidation and peroxisome proliferation when considered on a mumol/day basis. As palmitic acid and hexadecanedioic acid only marginally affected these hepatic responses, it is conceivable that the potency of the selected compounds as proliferators of peroxisomes and inducers of the associated enzymes depends on their accessibility for beta-oxidation.
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PMID:Alkylthio acetic acids (3-thia fatty acids)--a new group of non-beta-oxidizable peroxisome-inducing fatty acid analogues--II. Dose-response studies on hepatic peroxisomal- and mitochondrial changes and long-chain fatty acid metabolizing enzymes in rats. 257 77

Experimental infection of golden hamsters with Leishmania donovani caused significant alterations in the hepatic microsomal mixed function oxidase system. Gross examination of liver indicated hepatomegaly. Microsomal protein contents were only marginally elevated. Cytochrome P-450 as well as haem contents were significantly decreased and it directly correlated with the degree of infection. Cytochrome b5 exhibited elevation at lower degrees of infection which came down to control levels at the peak infection. Concomitant suppression was also noticed in cytochrome P-450 dependent monooxygenase activities, viz. aniline hydroxylase, benzo[a]pyrene hydroxylase and aminopyrine N-demethylase. No significant change was observed in NADH-cytochrome b5 reductase and NADPH-cytochrome c reductase. The results indicate suppression of hepatic microsomal MFO activities during visceral leishmaniasis.
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PMID:Suppression of the hepatic microsomal cytochrome P-450 dependent mixed function oxidase activities in golden hamster during Leishmania donovani infection. 259 7

The hepatic glucose-6-phosphatase system was studied with a novel microanalytical technique in adult patients undergoing liver biopsy. 4 patients were diagnosed as having type 1 glycogen storage disease (GSD). 3 of these patients, who had hypoglycaemic symptoms, had variations of type 1a GSD, which is caused by a defect in the hepatic microsomal glucose-6-phosphatase enzyme. The fourth, with hepatomegaly and no hypoglycaemic symptoms, had a normal glucose-6-phosphatase enzyme but a defect in the hepatic microsomal phosphate/pyrophosphate translocase T2; this is the first report of an adult with type 1c GSD. Adult type 1 GSD should be considered in patients with unresolved hypoglycaemic symptoms and/or unresolved hepatomegaly.
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PMID:Diagnosis of type 1a and type 1c glycogen storage diseases in adults. 288 97

The effect of methotrexate on lipids in serum and liver and key enzymes involved in esterification and oxidation of long-chain fatty acids were investigated in rats fed a standard diet and a defined choline-deficient diet. Hepatic metabolism of long-chain fatty acids were also studied in rats fed the defined diet with or without choline. When methotrexate was administered to the rats fed the standard diet there was a slight increase in hepatic lipids and a moderate reduction in the serum level. The palmitoyl-CoA synthetase activity and the microsomal glycerophosphate acyltransferase activity in the liver of rats were increased by methotrexate. The data are consistent with those where the liver may fail to transfer the newly formed triacylglycerols into the plasma with a resultant increase in liver triacylglycerol content and a decrease in serum lipid levels. Fatty liver of methotrexate-exposed rats can not be attributed simply to a reduction of fatty acid oxidation as the carnitine palmitoyltransferase activity was increased. The methotrexate response in the rats fed the defined choline-deficient diet was different. There was a reduction in both serum and hepatic triacylglycerol and the glycerophosphate acyltransferase and palmitoyl-CoA synthetase activities. The carnitine palmitoyltransferase activity was unchanged. Hepatomegaly and increased hepatic fat content, but decreased serum triacylglycerol, total cholesterol and HDL cholesterol were found to be related to the development of choline deficiency as the pleiotropic responses were almost fully prevented by addition of choline to the choline-deficient diet. Addition of choline to the choline-deficient diet normalized the total palmitoyl-CoA synthetase and carnitine palmitoyltransferase activities. In contrast to methotrexate exposure, choline deficiency increased the mitochondrial glycerophosphate acyltransferase activity. The data are consistent with those of where fatty liver induction of choline deficiency may be related to an enhanced esterification of long-chain fatty acids concomitant with a reduction of their oxidation.
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PMID:Effect of methotrexate on long-chain fatty acid metabolism in liver of rats fed a standard or a defined, choline-deficient diet. 296 71


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