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)

From 12 patients with liver cirrhosis and hyperbilirubinaemia, the different conjugates of bilirubin and bile acids in the serum were separated and determined. The serum of the patients contained varying amounts of unconjugated bilirubin, which was not correlated to total serum bilirubin. No correlation between bilirubin conjugates and different conjugates of bile acids could be found, indicating different elimination processes for these substances. To examine whether a changed plasma transport of bile acids, which may contribute to the different excretion pattern of bilirubin and bile acids, occurs in liver cirrhosis, the bile acids in the different serum lipoprotein fractions were determined in seven of the patients. It was found that 40% of serum bile acids were bound to serum lipoproteins, despite decreased serum lipoprotein levels. The degree of lipoprotein binding of bile acids was not correlated to total serum bile acid concentrations. Cholic acid conjugates were present to a higher extent in the lipoprotein fractions than those of chenodeoxycholic acid or of deoxycholic acid. Determination was made of the distribution of individual conjugates between different lipoproteins and it was found that most of the glycine conjugates were present in high density lipoprotein, whereas the main part of sulphates and taurine conjugates were present in low density lipoprotein. These results indicate that a higher fraction of bile acids in liver cirrhosis is transported by lipoproteins in plasma, which may be of importance for the hepatic elimination of bile acids in cases with this disease.
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PMID:Transport of serum bile acids in patients with liver cirrhosis and hyperbilirubinaemia. 285 44

Bile acid pool size and kinetics were determined in 17 patients with cirrhosis and 11 patients without liver disease and correlated with the severity of liver disease as determined by the usual clinical and laboratory criteria. In order to assess the severity of liver disease, a grading system was devised which assigned numerical values to various clinical signs and laboratory results. The total clinical score and the patients were divided into two groups of advanced (7-18 points) or mild (1-6 points) cirrhosis. The clinical rating was then correlated with the various aspects of bile acid metabolism. Cholic acid synthesis was markedly reduced in the early stages of cirrhosis and continued to decrease with the advancement of the liver disease. There was an inverse correlation between synthesis of cholic acid and the severity of cirrhosis. Nine of the 10 patients with advanced cirrhosis and a very low cholic acid synthetic rate (average 68 mg per day) died within one to 13 months from the start of the study. Patients with mild cirrhosis also had significantly reduced cholic acid synthesis (average 152 mg per day) but they all were well and alive three to 23 months after the study. In contrast, chenodeoxycholic acid synthesis was not markedly affected in either patients with mild or advanced cirrhosis. There was also a high degree of correlation between the fractional daily turnover rate of cholic acid and the severity of liver disease. The fractional daily turnover rate of cholic acid was greatly reduced (50%) in patients with advanced cirrhosis. Deoxycholic acid was reduced in patients with mild cirrhosis and virtually absent from the bile of patients with advanced cirrhosis. The findings of the present report provide evidence that cholic acid synthesis is a sensitive indicator of the hepatocellular damage, whereas chenodeoxycholic acid synthesis is relatively unaffected by cirrhosis. The selective alteration in cholic acid synthesis probably resides in a deficiency of one or more enzymes regulating the formation of the 3-keto, 7 alpha, 12 alpha-dihydroxy precursor of cholic acid.
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PMID:Cholic acid synthesis as an index of the severity of liver disease in man. 476 10

Ethanol has been demonstrated to cause aberrations in lipoprotein metabolism, cholesterol synthesis, biliary secretion, and bile acid synthesis. Although there is interdependency of cholesterol and bile acid metabolism, a role of ethanol-induced lipid abnormalities in altering bile acid synthesis has not been found. The direct effects of ethanol administration on bile acid metabolism have been studied in animals and vary with the experimental design. Acutely, ethanol causes decreased bile acid secretion and synthesis, but other effects are less well defined. Chronic ethanol use in man may result in cirrhosis, a condition in which abnormalities of bile acid metabolism have been described in detail. Cholic acid synthesis and pool size are markedly depressed in advanced cirrhosis. Chenodeoxycholic acid synthesis is affected less than cholic acid synthesis, probably because 12 alpha-hydroxylase activity is markedly depressed in cirrhosis, although other steps may also be influenced such as 7 alpha-hydroxylation of cholesterol or availability of cholesterol precursor. The deoxycholic acid pool is depressed probably because of changes in fecal flora. Despite the decrease in total bile acid pool, lithogenicity of bile is not increased in cirrhotic patients because of a concomitant decline in cholesterol and phospholipid secretion. Changes in hepatic blood flow and hepatic extraction cause an increase in plasma bile acid levels which may have clinical relevance.
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PMID:Effects of acute and chronic ethanol intake on bile acid metabolism. 701 54

In order to evaluate more definitively the observed aberrations in the synthesis of cholic and chenodeoxycholic acids in patients with advanced cirrhosis, two bile acid biosynthesis pathways were examined by determining the efficiency of conversion of [3H]7 alpha-hydroxycholesterol and [3H] 26-hydroxycholesterol to primary bile acids. Bile acid kinetics were determined by administration of [14C]cholic and [14C]chenodeoxycholic acids. Cholic acid synthesis in cirrhotic patients was markedly depressed (170 vs. 927 mumoles per day)( while chenodeoxycholic acid synthesis was reduced to a much lesser degree (227 vs. 550 mumoles per day). The administration of [3H]7 alpha-hydroxycholesterol allowed for an evaluation of the major pathway of bile acid synthesis via the 7 alpha-hydroxylation of cholesterol. This compound was efficiently incorporated into primary bile acids by the two normal subjects (88 and 100%) and two cirrhotic patients (77 and 91%). However, the recovery of the label in cholic acid was slightly less in cirrhotic patients than in normal subjects. [3H]26-hydroxycholesterol was administered to ascertain the contribution of the 26-hydroxylation pathway to bile acid synthesis. All study subjects showed poor conversion (9 to 22%) of this intermediate into bile acids. The results of this study suggest that a major block in the bile acid synthesis pathway in cirrhosis is at the level of 7 alpha-hydroxylation of cholesterol (impairment of 7 alpha-hydroxylase) and /or in the feedback triggering mechanism regulating bile acid synthesis. The data also suggest that the 26-hydroxylation pathway in normal subjects and patients with cirrhosis is a minor contributor to synthesis of the primary bile acids. Therefore, the relative sparing of chenodeoxycholic acid synthesis observed in cirrhotic patients is not due to preferential synthesis of this bile acid via the 26-hydroxylation pathway.
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PMID:Bile acid metabolism in cirrhosis. VIII. Quantitative evaluation of bile acid synthesis from [7 beta-3H]7 alpha-hydroxycholesterol and [G-3H]26-hydroxycholesterol. 705 68

In chronic cholestatic liver disease hydrophobic and potentially cytotoxic bile acids are assumed to accumulate in the liver. To test this hypothesis we investigated bile acid levels and pattern in livers and serum of patients with, (A) end-stage chronic cholestatic liver disease, and with (B) end-stage cirrhosis of alcoholic/chronic hepatitic origin who underwent liver transplantation. Bile acids were also analyzed in (C) normal liver tissue. Levels of bile acids were 215 +/- 39.1 nmol/g liver (wet weight) in chronic cholestasis and 120 +/- 32.7 and 56.1 +/- 24.2 nmol/g liver in group B and group C (P < 0.01 and P < 0.005), respectively. Cholic acid was the prevailing bile acid in chronic cholestasis (51%) and was elevated eight-fold as compared to group C (P < 0.005). Chenodeoxycholic acid contributed 41% to total bile acids and was elevated four-fold (P < 0.005). Deoxycholic acid contributed only 1.5% to bile acids in chronic cholestasis as compared to 27% in group C (P < 0.01) and was absent in group B. Levels of lithocholic acid tended to be increased in chronic cholestasis as compared to group C and its sulfation was impaired (P < 0.05). The pattern of serum bile acids in chronic cholestasis agreed well with the bile acid pattern in the explanted livers. We conclude that hepatic accumulation of hydrophobic chenodeoxycholic acid and impaired sulfation of lithocholic acid might contribute to tissue degeneration in chronic cholestatic liver disease due to the detergent effects of these bile acids.
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PMID:Hepatic levels of bile acids in end-stage chronic cholestatic liver disease. 886 72

Marked hemodynamic changes occur in humans and experimental animals with cirrhotic liver disease. In the heart, basal contractility, responsiveness to beta-adrenoceptor activation, and excitation-contraction coupling (ECC) are negatively affected in models of cirrhosis and portal hypertension with portosystemic shunting (PVS), and comprise what has been called cirrhotic cardiomyopathy. These effects are accompanied by elevated circulating levels of bile acids. We investigated whether elevated bile acids act as a myocardial toxicant by exposing cardiac muscle in vitro to bile acids and compared these results with two models of cirrhotic cardiomyopathy with elevated bile acids: CCl4-induced cirrhosis and PVS. Cholic acid, a lipophilic bile acid, produced a decrease in basal cardiac contractility and responsiveness to beta-adrenoceptor activation, both of which appeared to result from altered ECC. beta-Adrenoceptor density and signaling were unaffected. Acutely, ursodeoxycholic acid, a more hydrophilic bile acid, had no effect. Cirrhosis produced a decrease in basal force, depressed beta-adrenoceptor responsiveness, and altered ECC similar to cholic acid. However, cirrhosis also altered beta-adrenoceptor signaling including decreases in cyclic AMP formation, expression of the stimulatory G protein, GS, and beta-adrenoceptor density. Displacement of lipophilic bile acids by chronic administration of ursodeoxycholic acid to rats during the development of cirrhotic cardiomyopathy produced by PVS produced attenuation of the effect on ECC. These results suggest a possible role for lipophilic bile acids in some, but not all of the myocardial consequences of chronic portal vein stenosis and CCl4-induced cirrhosis.
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PMID:The role of lipophilic bile acids in the development of cirrhotic cardiomyopathy. 2041 15

Previously, we have found that intracellular calcium homeostasis is altered in platelets from an experimental model of liver cirrhosis, the bile-duct ligated (BDL) rat; these alterations are compatible with the existence of a hypercoagulable state and related to an enhanced intracellular calcium release evoked by thrombin and an increased amount of calcium stored in the intracellular organelles. In the present study we have investigated the role of bile acids in those alterations of the BDL cirrhotic model. Cholic acid (CA) or deoxycholic acid (DCA) did not change P-selectin expression or platelet aggregation in any group but elevated baseline platelet calcium levels. Incubation with both bile acids reduced calcium release after stimulation with thrombin in the absence of extracellular calcium. Pretreatment with CA but not with DCA reduced significantly thrombin-induced calcium entry in all three experimental groups. The capacitative calcium entry was also significantly lower in platelets pretreated with both bile acids. The simultaneous addition of thapsigargin and ionomycin to estimate the total amount of calcium in platelet internal stores was decreased by pretreatment with both CA and DCA, although these changes were significantly different in the control rats only with CA and in the BDL platelets with DCA. These results indicate that CA and DCA reduce calcium movements in platelets of control and BDL animals, thus suggesting that bile acids do not participate in the alterations observed in the BDL cirrotic model.
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PMID:Bile Acids Do Not Contribute to the Altered Calcium Homeostasis of Platelets from Rats with Biliary Cirrhosis. 2863 47