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)

Carnitine is synthesized from lysine and methionine. In the rat, inadequate intake of either of these essential amino acids causes carnitine depletion. Inasmuch as protein deficiency is common in the hospital population, we have investigated the possible occurrence of nosocomial carnitine deficiency. Fasting serum carnitine concentration was measured in 16 normal and 247 patients in 16 disease groups. Normal range of carnitine was 55-103 muM. Only the cirrhotic group showed significant (P < 0.05) hypocarnitinemia. 14 of 36 hospitalized cirrhotics had subnormal values for serum carnitine. The creatinine/height index, midarm muscle circumference, and triceps skin-fold thickness indicated protein-calorie starvation in the 14 hypocarnitinemic liver patients. In six of the hypocarnitinemic cirrhotics (average serum level 50% of normal), spontaneous dietary intakes of carnitine, lysine, and methionine were measured and found to be only 5-15% as great as in six normocarnitinemic, healthy controls. When these six cirrhotic and six normal subjects were given the same lysine-rich, methionine-rich, and carnitine-free nutritional intake, the normals maintained normal serum carnitine levels and excreted 100 mumol/day, whereas the cirrhotics' serum level fell to 25% of normal, and urinary excretion declined to 15 mumol/day. Seven hypocarnitinemic cirrhotics died. Postmortem concentrations of carnitine in liver, muscle, heart, kidney, and brain averaged only one-fourth to one-third those in corresponding tissues of eight normally nourished nonhepatic patients who died after an acute illness of a 1-3-day duration. THESE DATA SHOW THAT CARNITINE DEPLETION IS COMMON IN PATIENTS HOSPITALIZED FOR ADVANCED CIRRHOSIS, AND THAT IT RESULTS FROM THREE FACTORS: substandard intake of dietary carnitine; substandard intake of lysine and methionine, the precursors for endogenous carnitine synthesis; and loss of capacity to synthesize carnitine from lysine and methionine.
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PMID:Deficiency of carnitine in cachectic cirrhotic patients. 89 75

L-carnitine (L-C) is a naturally occurring substance in mammalian tissues that has recently been proposed as a therapeutic agent in hepatic encephalopathy and liver steatosis. L-C also produces some acute, non-metabolic, haemodynamic effects that have not previously been studied in patients with cirrhosis. Therefore, the authors evaluated the acute effect of i.v. administration of L-C (30 mg/kg) on systemic and splanchnic haemodynamics in ten patients (L-C group) with chronic liver disease (Child-Pugh's class A: 4, B: 3, C: 3 patients) and a control group composed of ten patients with similar clinical characteristics (Child-Pugh's class A: 5, B: 2, C: 3 patients) who received placebo. Heart rate, cardiac index and pulmonary arterial pressure (measured by right heart catheterization) decreased slightly but significantly in the L-C group and the changes observed in stroke volume were highly correlated to the Pugh's score. Moreover, the hepatic venous pressure gradient (measured by hepatic vein catheterization) decreased significantly in the L-C group, whereas no changes occurred in the placebo group. The overall response to L-C was contradictory to that previously observed in animals and humans with normal liver function, and the extent seemed to depend on the severity of liver disease. The effect of the drug on cardiac index, heart rate and hepatic venous gradient could possibly be beneficial for patients with hyperdynamic circulatory condition and portal hypertension.
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PMID:Acute systemic and splanchnic haemodynamic effects of L-carnitine in patients with cirrhosis. 145 45

The plasma level of carnitine, a co-factor involved in many metabolic reactions, is high in alcoholic liver cirrhosis, due to an increased amount of esterified carnitine. To determine if this alteration is linked to alcoholic liver disease or to liver cirrhosis per se. total carnitine, free carnitine, total esterified carnitine, short chain acylcarnitine and long chain acylcarnitine were measured in 41 patients suffering from liver cirrhosis of different aetiology and severity. In 19 of these patients, acetylcarnitine was also measured. Moreover, multivariate analysis was performed to assess the association of carnitine plasma levels with nutritional and liver disease indices. Of the nutritional indices (creatinine/height ratio, mid upper arm muscle circumference and triceps skinfold) only triceps skinfold appeared to be weakly correlated with carnitine (with long chain acylcarnitine). Significantly high levels of acetylcarnitine, short chain acylcarnitine, total esterified carnitine and total carnitine were found in cirrhotics independently of the aetiology of cirrhosis, even though a trend towards higher levels of acetylcarnitine was evident in heavy drinkers. Direct correlations of gamma-glutamyltransferase with acetylcarnitine, acetylcarnitine/free carnitine, short chain acylcarnitine/free carnitine and total esterified carnitine/free carnitine were found. Carnitine plasma levels did not differ in the three Pugh-Child's classes; however, a trend towards higher levels of acetylcarnitine was found in Pugh-Child's class C. In conclusion, the high levels of acetylcarnitine, short chain acylcarnitine, total esterified carnitine and total carnitine found in cirrhosis were linked to liver disease. Alcohol abuse seemed only to be an exacerbating factor.
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PMID:Plasma carnitine levels in liver cirrhosis: relationship with nutritional status and liver damage. 198 Dec 22

In a group of liver cirrhosis (LC) patients subjected to a rectal ammonium overload test, the effect of L-carnitine on ammoniemia and on the type A numerical connection and star clock psychomotor tests has been evaluated. On comparing 40 LC patients given L-carnitine with 40 control cirrhotics given a placebo, no significant differences were observed in ammonium levels after performing the overload test in both groups. However, on studying the patients with the greatest liver involvement, those given L-carnitine showed smaller elevations in ammoniemia and better responses to the psychometric tests than those receiving the placebo. The results obtained emphasize the need to continue testing the effect of L-carnitine using either similar tests or carrying out long-term evaluations to determine its protective effect in the appearance of hepatic encephalopathy, perhaps even including its evaluation in the treatment of established encephalopathy.
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PMID:Effect of L-carnitine upon ammonia tolerance test in cirrhotic patients. 210 87

The authors report preliminary data on the behavior of some lipid fractions in cirrhosis of the liver and correlate them with the changes in the insulin, glucagon and C-peptide levels. Elevated FFA (Free Fatty Acids) and normal cholesterol, triglyceride and total lipid values indicate a prevalent insulin induced effect and a reduction of liver metabolism of these fractions. This hypothesis is supported by the fact that L-carnitine, which reestablishes the carnitine-dependent intracellular transport system, reduces the levels of all the lipid fractions studied. The normal C-peptide values in these patients with liver cirrhosis show that hyperinsulinemia is caused by impaired metabolism of this hormone and not by hyperincretion. This hyperinsulinemia seems to react positively to the improvement of the intracellular transport systems. A fall in the hyperglucagonemia follows the decreased hyperinsulinemia leading to a hormone balance with lower values and a consequent reduction of the hormonal stimuli on the lipid metabolism. The possibility of administering drugs, which can act on the metabolic pathways responsible for the high FFA plasma levels, which seem to play a role in the physiopathology of encephalopathies and hepatic coma is clinically interesting.
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PMID:[Plasma lipids, insulin, C-peptide, and glucagon levels in cirrhosis: personal observations]. 267 5

Persistent abnormalities of liver function tests occur in approximately 15% of home parenteral nutrition (HPN) patients and are associated with steatosis, steatohepatitis, and, rarely, fibrosis or cirrhosis. Approximately one-third of patients with gut failure on long-term HPN have low total and free plasma carnitine concentrations, and it has been suggested that a deficiency of L-carnitine may be responsible for the steatosis and steatohepatitis in HPN patients. To determine whether administration of L-carnitine is capable of reversing steatosis in HPN patients, 4 adult women on HPN for a mean of 53 mo (range 21-80 mo) were studied before and after 1 mo of intravenous L-carnitine supplementation (1 g/day). All patients had abnormalities in standard liver function tests and low total and free plasma carnitine values. The mean total and free plasma carnitine concentrations and the mean total hepatic carnitine concentration were reduced before supplementation and rose to normal values after treatment (27.4 +/- 2.3 to 35.5 +/- 3.1 nmol/ml, 19.4 +/- 2.8 to 25.7 +/- 2.5 nmol/ml, and 3.5 +/- 0.65 to 6.5 +/- 1.2 nmol/mg of noncollagen protein, respectively). However, there were no significant changes in mean serum aspartate aminotransferase and alkaline phosphatase levels (65 +/- 21 vs. 54 +/- 12 IU and 429 +/- 220 vs. 472 +/- 224 IU, respectively), plasma free fatty acids, plasma triglycerides, hepatic free fatty acid and triglyceride concentrations, or the grade of hepatic steatosis on light microscopy. These results suggest that carnitine deficiency is not a major cause of steatosis and steatohepatitis in patients receiving HPN.
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PMID:L-carnitine therapy in home parenteral nutrition patients with abnormal liver tests and low plasma carnitine concentrations. 312 32

Carnitine (beta-hydroxy-gamma-N-trimethylaminobutyric acid) is required for transport of long-chain fatty acids into the inner mitochondrial compartment for beta-oxidation. Widely distributed in foods from animal, but not plant, sources, carnitine is also synthesized endogenously from two essential amino acids, lysine and methionine. Human skeletal and cardiac muscles contain relatively high carnitine concentrations which they receive from the plasma, since they are incapable of carnitine biosynthesis themselves. Since the discovery of a primary genetic carnitine deficiency syndrome in 1973, carnitine has become the subject of extensive research. It is now recognized that carnitine deficiency may also occur secondary to genetic disorders of intermediary metabolism as well as to a variety of clinical disorders, including renal disease treated by hemodialysis, the renal Fanconi syndrome, cirrhosis, untreated diabetes mellitus, malnutrition, Reye's syndrome, and certain disorders of the endocrine, neuromuscular, and reproductive systems. Administration of the anticonvulsant valproic acid and total parenteral nutrition may also induce hypocarnitinemia. In many instances, the physiological implications of secondary carnitine deficiency have not been resolved. However, evidence for a specific carnitine requirement for the newborn, especially if preterm, is accumulating. Moreover, carnitine administration may have a favorable effect on some forms of hyperlipoproteinemia. Carnitine, now recognized as a conditionally essential nutrient, is a significant factor in preventive medicine.
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PMID:Carnitine: an overview of its role in preventive medicine. 353 87

Carnitine is essential for the oxidation of fatty acids. The liver is a major site of fatty oxidation. To determine if there are alterations in plasma carnitine in patients with alcoholic cirrhosis, we measured plasma carnitine and its metabolites by a specific radioenzymatic method in 20 men with hepatic cirrhosis and 30 healthy volunteers. We found total carnitine, free carnitine, short-chain acylcarnitines, and long-chain acylcarnitines to be significantly elevated in the cirrhotic subjects. The mean values for total carnitine, free carnitine, short-chain acycarnitines, and long-chain acylcarnitines for the cirrhotic patients and the control subjects were 73.1 vs. 46.1, 47.0 vs. 36.7, 17.9 vs. 5.7 and 8.2 vs. 3.7 microM, respectively. The greatest increases were noted in the acylcarnitines; 3-fold for short-chain acylcarnitines and over 2-fold for long-chain acylcarnitines. We conclude that alcoholic cirrhosis is a hypercarnitinemic condition.
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PMID:Elevated plasma carnitine in hepatic cirrhosis. 686 67

Carnitine metabolism was studied in 79 patients with chronic liver disease, including 22 patients with noncirrhotic liver disease and 57 patients with different types of cirrhosis (22 patients with hepatitis B- or C-associated cirrhosis, 15 patients with alcohol-induced cirrhosis, 15 patients with primary biliary cirrhosis [PBC], and 5 patients with cryptogenic cirrhosis), and compared with 28 control subjects. In comparison with control subjects, patients with noncirrhotic liver disease showed no change in the plasma carnitine pool, whereas patients with cirrhosis had a 29% increase in the long-chain acylcarnitine concentration. Analysis of subgroups of patients with cirrhosis showed that patients with alcohol-induced cirrhosis had an increase in the total plasma carnitine concentration (67.8 +/- 29.5 vs. 55.2 +/- 9.9 micromol/L in control subjects), resulting from increases in both the short-chain and long-chain acylcarnitine concentration. In this group of patients, the acylcarnitine concentrations showed a close correlation with the total carnitine concentration, and the total carnitine concentration with the serum bilirubin concentration. Urinary excretion of carnitine was not different between patients with noncirrhotic or cirrhotic liver disease and control patients. However, patients with PBC showed an increased urinary excretion of total carnitine (52.5 +/- 40.0 vs. 28.0 +/- 16.7 micromol carnitine/mmol creatinine), resulting from an increase in the fractional excretion of both free carnitine and short-chain acylcarnitine. The current studies show that patients with cirrhosis are normally not carnitine deficient. Patients with alcohol-induced cirrhosis have increased plasma carnitine concentrations, which may result from increased carnitine biosynthesis because of increased skeletal muscle protein turnover. The increase in the fractional carnitine excretion in patients with primary biliary cirrhosis may result from competition of bile acids and/or bilirubin with tubular carnitine reabsorption and/or from a reduced activity of the carnitine transporter located in the proximal tubule.
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PMID:Carnitine metabolism in patients with chronic liver disease. 898 81

Chronic administration of a soybean-derived polyenylphosphatidylcholine (PPC) extract prevents the development of cirrhosis in alcohol-fed baboons. To assess whether this phospholipid also affects earlier changes induced by alcohol consumption (such as fatty liver and hyperlipemia), 28 male rat littermates were pair-fed liquid diets containing 36% of energy either as ethanol or as additional carbohydrate for 21 d, and killed 90 min after intragastric administration of the corresponding diets. Half of the rats were given PPC (3 g/l), whereas the other half received the same amount of linoleate (as safflower oil) and choline (as bitartrate salt). PPC did not affect diet or alcohol consumption [15.4 +/- 0.5 G/(kg.d)], but the ethanol-induced hepatomegaly and the hepatic accumulation of lipids (principally triglycerides and cholesterol esters) and proteins were about half those in rats not given PPC. The ethanol-induced postprandial hyperlipemia was lower with PPC than without, despite an enhanced fat absorption and no difference in the level of plasma free fatty acids. The attenuation of fatty liver and hyperlipemia was associated with correction of the ethanol-induced inhibition of mitochondrial oxidation of palmitoyl-1-carnitine and the depression of cytochrome oxidase activity, as well as the increases in activity of serum glutamate dehydrogenase and aminotransferases. Thus, PPC attenuates early manifestations of alcohol toxicity, at least in part, by improving mitochondrial injury. These beneficial effects of PPC at the initial stages of alcoholic liver injury may prevent or delay the progression to more advanced forms of alcoholic liver disease.
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PMID:Polyenylphosphatidylcholine attenuates alcohol-induced fatty liver and hyperlipemia in rats. 927 63


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