Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The accelerated transport of the blood neutral amino acids into the brain in encephalopathic patients with fulminant hepatitis and advanced liver cirrhosis was demonstrated not only by determining the cerebrospinal fluid (CSF) aminogram but also by calculating the predicted velocity of the amino acid transport through the blood-brain barrier. Significant elevation in CSF aromatic amino acid (AAA) and methionine levels was observed in the encephalopathic patients. Arousal from hepatic encephalopathy by drip infusion of a branched chain amino acid (BCAA)-enriched solution was obtained coincidentally with the elevated BCAA levels and diminished concentrations of AAA and methionine in CSF. These clinical observations were confirmed experimentally in rats treated with carbon tetrachloride (CCl4) and D-galactosamine by obtaining the elevation of neutral amino acid contents in the brain and the slight increase in the brain uptake index (BUI) of a radiolabeled amino acid.
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PMID:Alterations in neutral amino acid transport across the blood-brain barrier in hepatic failure. 663 35

The amino acid solution, Aminofusin hepar, was evaluated for treatment of hepatic encephalopathy and for parenteral nutrition of patients with liver cirrhosis in correlation to changes in amino acid levels. In contrast to amino acid solutions used for the parenteral nutrition of patients without liver disease, this solution contains an increased proportion of branch chained amino acids and of arginine and ornithine, and a reduced proportion of phenylalanine, methionine, glycine and threonine. The changes in the plasma amino acid levels after infusion of this solution were measured in 4 cirrhotics. The concentration of leucine, isoleucine, valine, ornithine and arginine increased markedly, whereas phenylalanine, methionine, tyrosine, glycine and threonine decreased. The ammonia level in venous blood increased slightly. 4 cirrhotics with encephalopathy were treated for 7 days. In 3 of them the neuropsychiatric symptoms were completely reversed, whereas in the remaining 1 no clinical improvement was achieved in spite of normalization of the plasma aminogramm. In this patient a constant rise of blood ammonia was noted. The indications for special amino acid solutions in liver diseases are discussed.
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PMID:[Parenteral feeding of patients with liver cirrhosis with hepatic encephalopathy]. 677 52

Development of alcohol-related liver and other diseases appears to be modified by host and environmental factors that include diet and nutritional status, exposure to other drugs and toxins, and infection. The relative importance of alcohol toxicity and malnutrition in the induction of fatty liver and cirrhosis, the subject of this report, has been debated. Male rhesus (M mulatta) monkeys were fed purified liquid diets, adequate or marginally deficient in lipotropes (choline, methionine, and folate), containing ethanol to supply 40-50% of calories for 1.5-4.5 years. Controls, fed the diets with sucrose and fat isocalorically substituted for ethanol, grew well and were clinically normal. Ethanol-fed monkeys in both diet groups failed to gain weight and were slightly anemic, with mild derangements of serum electrolytes and small amounts of fat in their livers. None had fibrosis or cirrhosis until the severity of the lipotrope-deficiency was increased; then two of four deficient animals developed cirrhosis and one developed fibrosis. (The severe deficiency induced weight loss and fatty liver, but not fibrosis, in one of two controls.) We conclude that alcohol does not induce hepatic fibrosis or cirrhosis in rhesus monkeys fed a nutritionally complete diet, a result supported by studies in rats and another monkey, M radiata. Alcohol does induce cirrhosis when fed in combination with a lipotrope-deficient diet that is not, by itself, cirrhogenic.
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PMID:Ethanol and diet interactions in male rhesus monkeys. 692 13

1. Intravenous infusions of L-valine (600 mumol/min), L-isoleucine (150 mumol/min), L-leucine (300 mumol/min) and a mixture of the three branched-chain amino acids (70% L-leucine, 20% L-valine, 10% L-isoleucine; 270 mumol/min) were given to four groups of healthy volunteer subjects. Whole-blood concentrations of amino acids and glucose and serum insulin were measured before and during the infusions. 2. Valine and isoleucine infusions resulted in twelve- and six-fold increases in the respective amino acid. During valine infusion, tyrosine was the only amino acid for which a decrease in concentration was seen (25%, P less than 0.05). With isoleucine administration, no significant changes were found. In contrast, leucine infusion (during which the leucine concentration rose about sixfold) was accompanied by significant decreases in tyrosine (35%), phenylalanine (35%), methionine (50%), valine (40%) and isoleucine (55%). The arterial glucose concentration fell slightly (5%) and the insulin concentration increased 20% during leucine infusion. 3. Infusion of the mixture of the three branched-chain amino acids resulted in marked decreases in tyrosine (50%), phenylalanine (50%) and methionine (35%). The decreased amino acid levels remained low for 2 h after the end of the infusion. 4. The present findings demonstrate that intravenous infusion of leucine (not infusion of valine or isoleucine) results in marked reductions in the concentrations of the aromatic amino acids and methionine. Infusion of a mixture of the three branched-chain amino acids gives results similar to those obtained with leucine infusion alone. Thus a mixed branched-chain amino acid solution with leucine as its main constituent seems to be the best alternative in the treatment of patients with hepatic cirrhosis and encephalopathy.
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PMID:A comparison of the effects of intravenous infusion of individual branched-chain amino acids on blood amino acid levels in man. 701 2

1. The metabolic effect of alpha-oxoisocaproate (4-methyl-2-oxovalerate) infusion was examined in six patients with cirrhosis and in nine healthy control subjects. The arterial concentrations of amino acids, urea, ammonia, insulin and catecholamines were determined in the basal state and during intravenous infusion of alpha-oxoisocaproate (300 mumol/min) for 150 min. The exchanges of amino acids and substrates across the splanchnic region, the brain and the leg were examined in the healthy subjects by a catheter technique. 2. Basal alpha-oxoisocaproate levels were similar in patients and control subjects. During infusion the concentrations of alpha-oxoisocaproate rose to 90-130 mumol/l; they were 20-35% lower in the patients. Arterial leucine concentration increased in both groups to 250-300 mumol/l. Valine and isoleucine concentraions decreased (50-60%) as did to a lesser extent the concentrations of aromatic amino acids and methionine. 3. Regional exchange of amino acids was not significantly influenced by alpha-oxoisocaproate infusion. Arterial urea concentration decreased (12%, P less than 0.05) and ammonia levels rose (15-25%, P less than 0.05) in both groups. In the patients both adrenaline (100%, P less than 0.001) and noradrenaline concentrations were elevated (350%, P less than 0.001) in the basal state; insulin levels were similar to those in control subjects. 4. It is concluded that alpha-oxoisocaproate is rapidly transaminated to leucine in patients with cirrhosis and in healthy control subjects. alpha-Oxoisocaproate infusion resembles leucine infusion in its influence on aromatic amino acid concentrations, but in addition it elicits increased ammonia levels and decreased urea formation.
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PMID:Intravenous infusion of alpha-oxoisocaproate: influence on amino acid and nitrogen metabolism in patients with liver cirrhosis. 706 Mar 35

Plasma amino-acid concentrations were measured in 167 patients with liver disease of varying aetiology and severity, all free of encephalopathy, and the results compared with those in 57 control subjects matched for age and sex. In the four groups of patients with chronic liver disease (26 patients with chronic active hepatitis, 23 with primary biliary cirrhosis, 11 with cryptogenic cirrhosis, and 48 with alcoholic hepatitis +/- cirrhosis) plasma concentrations of methionine were significantly increased, while concentrations of the three branched chain amino-acids were significantly reduced. In the first three groups of patients plasma concentrations of aspartate, serine, and one or both of the aromatic amino-acids tyrosine and phenylalanine were also significantly increased, while in the patients with alcoholic hepatitis +/- cirrhosis plasma concentrations of glycine, alanine, and phenylalanine were significantly reduced. In the three groups of patients with minimal, potentially reversible liver disease (31 patients with alcoholic fatty liver, 10 with viral hepatitis, and 18 with biliary disease) plasma concentrations of proline and the three branched chain amino-acids were significantly reduced. Patients with alcoholic fatty liver also showed significantly reduced plasma phenylalanine values. Most changes in plasma amino-acid concentrations in patients with chronic liver disease may be explained on the basis of impaired hepatic function, portal-systemic shunting of blood, and hyperinsulinaemia and hyperglucagonaemia. The changes in patients with minimal liver disease are less easily explained.
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PMID:Plasma amino-acid patterns in liver disease. 707 13

1. Rats were given a purified folate-deficient diet containing 5 g succinylsulphathiazole/kg for 4-5 months in two experiments. Control rats were supplemented with folic acid in the drinking-water. 2. Weight gain was much below normal in the folate-deprived rats after the first month. Very low folate levels were recorded in blood, liver and peripheral nerve (12-33% of control). In the central nervous system, including the cerebrospinal fluid, the folate depletion was less conspicuous (50-80% of control). Only marginal signs of anaemia were found and no signs of neurological dysfunction were detected, using nerve conduction velocity measurement and co-ordination tests. 3. Light and electron microscopy of the folate deficient liver revealed fatty infiltration, and enlargement of liver parenchymal cells, nuclei and nucleoli. There was often a considerable amount of bile ductular cells in the lobuli but no cirrhosis. The morphological changes resembled those observed in choline deficiency. 4. Phospholipid N-methylation in liver was depressed in folate-deficiency. This was probably due to a decreased availability of S-adenosylmethionine caused by the low concentrations of methylated folate in liver. Intraperitoneal administration of methionine did not normalize phospholipid methylation. 5. In folate deficiency the proportion of ethanolamine phosphoglyceride in liver was increased at the expense of choline phosphoglyceride, which is consistent with a decreased phospholipid methylation. Also an increase in liver triacylglycerol was noted, in accordance with the morphological observations. Brain lipid composition was unchanged. 6. After the injection of labelled ethanolamine, isotope accumulated in liver phosphoethanolamine in folate deficiency, probably due to an impairment of the CTP:ethanolaminephosphate cytidylyltransferase (EC 2.7.7.14) reaction. The mechanism of this impairment is discussed. 7. Although the low concentrations of folate was the main nutritional change in the deprived animals, changes with respect to vitamin B12 and maybe also choline cannot be excluded. We conclude that some of the changes in folate deficiency, i.e. fatty liver and decreased biosynthesis of liver phospholipids may be due to a precipitated deficiency of lipotropic agents, whereas other differences may be specific for deficiency of folate per se, such as changes in liver phospholipid fatty acids and some of the morphological aberrations.
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PMID:Effect of experimental folate deficiency on lipid metabolism in liver and brain. 708 22

Hepatic encephalopathy in patients with severe liver disease was associated with marked elevation of either serum methionine or blood ammonia levels or with simultaneous moderate increases in both parameters. CSF methionine levels also increased in encephalopathic patients with fulminant hepatitis and liver cirrhosis. Increased influx of methionine into the brain over the theoretical values predicted from Pardridge's equation suggested that accelerated transport of serum methionine across the blood-brain barrier was observed in these cases with hepatic encephalopathy. Hepatic encephalopathy in acute carbon tetrachloride liver injury could be obtained experimentally following intraperitoneal injection of ammonium acetate in rats, which already received intragastric administration of methionine. However, similar encephalopathy could not be observed by the administration of glycine or leucine in place of methionine. These results suggest at least that methionine and ammonia act synergistically on inducing hepatic encephalopathy.
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PMID:Impaired metabolism of methionine in severe liver diseases. II. Clinical and experimental studies on role of impaired methionine metabolism in pathogenesis of hepatic encephalopathy. 710 99

Serum amino acid patterns in patients with different types of hepatic encephalopathy were investigated. Marked elevations in most of serum amino acids observed in untreated patients with acute type of fulminant hepatitis were not remarkable in the patients who have already treated; particularly branched chain amino acids (BCAA), phenylalanine and tyrosine were much lower in the latter group. However, elevation of serum methionine levels and lower ratio of BCAA/(phenylalanine + tyrosine) were similarly observed in both groups. In encephalopathic patients with decompensated cirrhosis, many amino acids such as phenylalanine, tyrosine and methionine were elevated with a slight depressed levels of serum BCAA. Highly significant decrease in serum BCAA levels and no elevation of phenylalanine and methionine with a minimal increase of tyrosine were observed in patients with chronic type of hepatic encephalopathy; other amino acids except for glutamine and arginine were much lower as compared to those in decompensated cirrhotics and even to the control values.
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PMID:Characteristics change in serum amino acid levels in different types of hepatic encephalopathy. 711 80

Methionine metabolism impairment in human liver disease has been related with an alteration in SAM-synthetase. This deficiency is produced by a post-translational event since human liver cirrhosis presents normal levels of SAM-synthetase mRNA in spite of a more than 50% diminution in its activity. A series of different experiments on the structure and activity of this enzyme have provided strong evidence that SAM-synthetase is regulated by reduced/oxidized glutathione ratio. Restoration of glutathione levels by the addition of S-adenosyl-methionine or glutathione esters in various experimental conditions (buthionine sulfoximine and carbon tetrachloride intoxication) resulted in a normalization of the SAM-synthetase diminution caused by the toxics and an attenuation of the morfological alteration produced in the liver, including fiber production. This findings might have pharmacological implications in the treatment of liver diseases, since the possible beneficial effect of long term administration of SAM could include a reduction of fiber production.
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PMID:S-adenosyl-L-methionine synthetase and methionine metabolism deficiencies in cirrhosis. 774 Oct 2


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