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

Studies were undertaken to evaluate the cytotoxicity of peripheral lymphocytes obtained from patients with alcoholic hepatitis. Lymphocyte cytotoxicity to Chang liver cells was investigated by a microcytotoxicity test, and that to autologous liver cells obtained by percutaneous liver biopsy was studied using a 51Cr release assay. Lymphocytes from patients with alcoholic hepatitis were found to be highly cytotoxic to Chang liver cells and autologous liver cells when compared to those of healthy subjects (P is less than 0.001). Cell-free supernatant fluid of lymphocytes from patients with alcoholic hepatitis incubated with purified alcoholic hyalin for 5 days was significantly cytotoxic to Chang liver cells (P is less than 0.01), indicating that a cytotoxic factor is elaborated by sensitized lymphocytes. A significant reduction in cytotoxicity was noted with disappearance of clinical features or direct addition of a purified isolate of alcoholic hyalin or its preincubation with lymphocytes. Preincubation of sensitized lymphocytes with acetaldehyde increased cytotoxicity for autologous liver beyond that obtained by the combined effects of lymphocytes alone and acetaldehyde alone (P is less than 0.001), interpreted as evidence that ethanol toxicity and hyperactivity of lymphocytes independently and collectively contribute to development of cirrhosis in patients with alcoholic hepatitis who continue to imbibe alcohol.
 ...
PMID:Lymphocyte cytotoxicity in alcoholic hepatitis. 6 6

The effects of ethanol on hepatic cellular metabolism and structure depend mainly on the dose and duration of intake. Following the ingestion of a substantial amount of ethanol, its presence alters a number of hepatic functions in part because of the change in the hepatic redox state (NADH/NAD ratio), resulting for instance in reduction of lipid oxidation. Furthermore, chronic ethanol consumption, at least in its early stages, produces adaptive metabolic changes in the endoplasmic reticulum which result not only in increased metabolism of drugs and accelerated lipoprotein production but also in activation of hepatotoxic compounds. Even more extended periods of ethanol intake result in damage to cell organelles in what can be considered a third stage of the alcohol effect namely that of injury. The injury involves primarily mitochondria, possibly as a consequence of effects of acetaldehyde, the first product of ethanol metabolism. Metabolites of ethanol also alter microtubular function. A defect in protein secretion may be the basis for protein retention and "ballooning" of the hepatocyte. Prolongation of ethanol induced injury eventually culminates in hepatic lesions such as alcoholic hepatitis and cirrhosis. Ethanol can be incriminated as a direct etiologic agent of the liver injury, since liver cirrhosis has been reproduced experimentally in baboons fed alcohol, despite an adequate diet.
 ...
PMID:[Pathogenesis of alcoholic liver injury (author's transl)]. 11 23

Significant liver disease including fatty metamorphosis, alcoholic hepatitis, cirrhosis, and hepatoma occur in two thirds of subjects who consume alcoholic beverages in sufficient quantities to interfere with work and social responsibilities; this is of major importance in the rapidly escalating morbidity and mortality from alcoholism. Chronic alcoholics should be routinely evaluated for the presence of altered liver function and structure. Clearance of indocyanine green using dichromatic ear densitometry and computer and analysis provides a simple and sensitive method for mass screening of such patients. Clinical studies of lymphocyte reactivity to purified alcoholic hyaline may be valuable in recognizing alcoholic hepatitis, the precursor of cirrhosis. Ethanol toxicity, malnutrition and constitutional factors contribute to the development of hepatic fibrosis and cirrhosis in alcoholics. Ethanol and/or acetaldehyde and the supernatant from lymphocytes stimulated by alcoholic hyaline cause a significant increase in the incorporation of proline into collagen of the damaged liver. Abstinence and correction of nutrient deficits are the cornerstones of treatment for alcoholic liver disease; a daily meal and dietary supplements should be provided for those with liver injury who continue to imbibe. Alcoholics with progressive liver disease despite supportive therapy may be aided by pharmacologic agents which suppress immunologic response and reduce fibrogenesis.
 ...
PMID:Liver disease of the alcoholic. 16 41

Histological study of 69 cases of cirrhosis, 9 of severe generalised hepatic fibrosis, and 19 of hepatocellular carcinoma showed an association with alcohol, hepatitis B surface antigen (HBsAg) or a1-antitrypsin bodies in, respectively, 41 (cirrhosis), 5 (fibrosis), and 9 (carcinoma). Eight of the cirrhotic cases and two of the carcinoma cases had double associations, HBsAg being present in all. Torcein and aldehyde fuchsin staining gave both false positive and false negative results when compared with immunofluorescence and immunoperoxidase methods for HBsAg. Large amounts of copper were found in four cirrhotic livers, and moderate amounts in 13: the diagnostic value of copper staining is questioned.
 ...
PMID:Aetiology of cirrhosis, hepatic fibrosis, and hepatocellular carcinoma. 19 27

Hepatic metabolism of ethanol to acetaldehyde by the alcohol dehydrogenase pathway is associated with the generation of reducing equivalents as NADH. Conversely, reducing equivalents are consumed when ethanol oxidation is catalyzed by the NADPH dependent microsomal ethanol oxidizing system. Since the major fraction of ethanol metabolism proceeds via alcohol dehydrogenase and since the oxidation of acetaldehyde also generates NADH, an excess of reducing equivalents is produced. This explains a variety of effects following acute ethanol administration, including hyperlactacidemia, hyperuricemia, enhanced lipogenesis and depressed lipid oxidation. To the extent that ethanol is oxidized by the alternate microsomal ethanol oxidizing system pathway, it slows the metabolism of other microsomal substrates. Following chronic ethanol consumption, adaptive microsomal changes prevail, which include enhanced ethanol and drug metabolism, and increased lipoprotein production. Severe hepatic lesions (alcoholic hepatitis and cirrhosis) develop after prolonged ethanol consumption in baboons. These injurious alterations are not prevented by nutritionally adequate diets and can therefore be ascribed to ethanol rather than to dietary inadequacy.
 ...
PMID:Differences in hepatic and metabolic changes after acute and chronic alcohol consumption. 24 Jul 42

Morphological characteristics of the liver and the presence of HBsAg in the blood serum, liver tissue, and pericholedocheal lymph nodes were examined in 25 patients with chronic liver diseases and 2 asymptomatic carriers of HBsAg. The antigen in tissues was demonstrated by indirect immunofluorescence and histochemically by staining with alcohol-arsein and aldehyde-fuxin. The antigen was found in the blood, liver tissue, and hepatocyte cytoplasm in both carriers and 10 patients. In 5 patients with liver cirrhosis and HBsAg antigenemia the antigen was also found in the liver tissue, in 1 patient it was absent in the blood but found in the liver, and in 2 patients it was absent in the blood and in the liver. In 5 patients with chronic hepatitis the antigen was demonstrated in the blood serum and the liver, in 12 patients it was not detected either in the blood or in the liver. In 8 patients enlarged pericholedocheal lymph nodes were examined, and in 6 of them HBsAg was detected in macrophages of the lymph nodes.
 ...
PMID:[Hepatitis B surface antigen in the liver and pericholedochal lymph nodes in chronic hepatitis and cirrhosis of the liver]. 44 82

The present paper is devoted to overview the basic concepts of ethanol-induced hepatic injury and therapeutic modalities by which alcoholic liver disease can be alleviated. The role of alcohol dehydrogenase of both hepatic and gastric origin as well as the importance of the number one metabolite acetaldehyde are discussed, furthermore the effects of microsomal ethanol oxidizing system are also described. The features of the major clinicopathological consequences of alcohol abuse fatty liver, alcoholic hepatitis are briefly outlined, and the basic pathogenetic mechanisms that lead to cirrhosis--cell necrosis, regeneration and fibroplasia--are shown. The understanding of the pathophysiology of alcohol-induced liver injury may improve the therapy with drugs and nutritional factors, and allow successful prevention through the early recognition of heavy drinkers before their social or medical disintegration. In the management of alcoholic liver diseases, among the true hepatoprotective agents a naturally occurring flavonoid silymarin and an active methyl-donor metabolite S-adenosyl-L-methionine seem to be promising. An antifibrotic treatment with colchicine might also be of importance. Further prospective, well-designed, controlled clinical trials are still warranted to evaluate real efficacy of these drugs. The hepatic consequences of alcohol abuse may be treatable, however, prevention would be the true resolution of the major global health problem of alcoholism.
 ...
PMID:Pathogenesis and management of alcoholic liver injury. 134

We recently found that polyunsaturated lecithin prevents ethanol from causing cirrhosis in the baboon. Because transformation of lipocytes to transitional cells plays a key role in hepatic fibrogenesis in vivo, and because this process in alcohol-fed baboons was found to be attenuated by polyunsaturated lecithin, we focused on lipocytes to study the mechanism of the protective effect. Rat lipocytes cultured on plastic undergo spontaneous activation, accompanied by expression of alpha-smooth muscle actin isoform and production of substantial amounts of type I collagen. The latter was further increased on incubation with acetaldehyde. This in vitro model was used here to study how acetaldehyde-mediated collagen production and accumulation can be turned off. Addition of polyunsaturated lecithin (10 mumols/L) was found to prevent the acetaldehyde-induced increase in collagen accumulation by 83% (p less than 0.001). By contrast, a saturated phospholipid (10 mumols/L dilauroyl phosphatidylcholine), a monounsaturated one (10 mumols/L linoleoyl-palmitoyl phosphatidylcholine) or linoleic acid (20 mumols/L bound to albumin) had no such effect. Incorporation of [3H]proline into collagen and the expression of alpha-1 (I) procollagen mRNA were increased by acetaldehyde; the latter was not significantly affected by polyunsaturated lecithin. Polyunsaturated lecithin increased lipocyte collagenase activity by 100% (p less than 0.001), whereas dilauroyl phosphatidylcholine, linoleoyl-palmitoyl phosphatidylcholine and linoleic acid had no such action. We concluded that (a) polyunsaturated lecithin selectively prevents the acetaldehyde-induced increase in collagen accumulation in lipocyte cultures, whereas other phospholipids or linoleate have no such effect; and (b) polyunsaturated lecithin does not modify the acetaldehyde-mediated increase in alpha-1 (I) procollagen mRNA, but it increases collagenase activity, suggesting that the protective effect exerted by polyunsaturated lecithin against alcohol induced fibrosis in vivo is due at least in part to stimulation of collagenase activity, which may prevent excess collagen accumulation by offsetting increased collagen production.
 ...
PMID:Polyunsaturated lecithin prevents acetaldehyde-mediated hepatic collagen accumulation by stimulating collagenase activity in cultured lipocytes. 137 80

Excessive consumption of ethanol results in reversible redox changes in the liver that are mainly responsible for the accumulation of triglycerides and the fatty liver of the alcoholic patient. In spite of continuing alcohol abuse, only a fraction of all alcoholics will develop alcoholic hepatitis and eventually cirrhosis. Genetic predisposition and environmental factors (in particular the often poor nutrition of the alcoholic) probably play an important role in the evolution of these complications. The generation of reactive oxygen species increases during the metabolism of ethanol, but their pathogenetic role in alcoholic liver disease in man is not clear. Acetaldehyde, a metabolite of ethanol, can react with proteins and form stable adducts. Such neoantigens may elicit an immunologic response which could in part be responsible for the liver cell damage associated with excessive alcohol consumption. Since no satisfactory animal model for alcoholic liver disease exists, the relative importance of the various factors involved in alcoholic liver disease is difficult to assess.
 ...
PMID:[Pathogenesis of alcoholic liver disease]. 158 33

Two types of factors can theoretically modulate alcohol metabolism toward increased acetaldehyde production. These factors are the following: (a) individual, genetically determined isoenzymes with distinct catalytic properties, and (b) modifications of enzyme activity induced by alcohol itself or liver damage. To investigate the respective roles of these factors in white individuals, we studied the alcohol dehydrogenase phenotype, together with liver alcohol dehydrogenase and aldehyde dehydrogenase activities, in 161 patients. Patients with alcoholic cirrhosis (n = 31) were compared with three types of controls: patients with nonalcoholic cirrhosis (n = 25) and excessive (n = 62) and moderate drinkers (n = 43) without liver disease. No association between alcohol dehydrogenase-3 phenotype and alcoholic cirrhosis was found. The prevalence of atypical alcohol dehydrogenase in the four groups was less than 1%. Patients with cirrhosis, regardless of its cause, had significantly lower alcohol dehydrogenase activity than the patients without cirrhosis (p less than 0.05 and p less than 0.01 vs. excessive and moderate drinkers, respectively). Among the noncirrhotic patients, alcohol dehydrogenase activity was significantly lower in the excessive drinkers than in the moderate drinkers (p less than 0.001). Aldehyde dehydrogenase activity was not different between cirrhosis-free excessive and moderate drinkers; in contrast, compared with these two groups, it was significantly lower in the two cirrhosis groups (p less than 0.01). These results suggest that no phenotypic pattern of alcohol dehydrogenase-3 associated with alcoholic cirrhosis in white patients exists, that liver alcohol dehydrogenase activity falls as a consequence of both alcohol abuse and cirrhosis and that liver aldehyde dehydrogenase activity is unaffected by alcohol abuse and only falls after the onset of cirrhosis.
 ...
PMID:Polymorphism of alcohol dehydrogenase, alcohol and aldehyde dehydrogenase activities: implication in alcoholic cirrhosis in white patients. The French Group for Research on Alcohol and Liver. 832 17


1 2 3 4 5 6 7 8 9 10 Next >>