Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ethanol is easily absorbed from the intestine and diffuses quickly throughout body water. The bulk of ethanol is metabolized in the liver, where alcohol dehydrogenase, a complex mixture of isoenzymes, oxidizes ethanol to acetaldehyde. Ethanol abuse produces functional and structural changes in the gastrointestinal tract, such as in the stomach, small intestine, liver, and pancreas. Accumulating evidence suggests direct toxicity of ethanol and possibly of acetaldehyde. Fatty liver, alcoholic hepatitis, liver cirrhosis, acute and chronic gastritis, deranged structure and function of the small intestine, acute and chronic pancreatitis, and pancreatic lithiasis are some of the sequelae of ethanol abuse. Recent investigations have enhanced our understanding of the functional and structural changes of the gastrointestinal tract produced by the abuse of ethanol.
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PMID:Ethanol, the liver, and the gastrointestinal tract. 719 92

Acetaldehyde, the first metabolite of ethanol, is capable to bind various proteins followed by the formation of acetaldehyde adducts. This condensate is supposed to act as a neoantigen. We have recently demonstrated the appearance of acetaldehyde adducts in liver of experimental animals after chronic ethanol treatment, and we produced an experimental hepatitis in guinea pig by immunization with acetaldehyde adducts and treatment with free access to ethanol. However the structure of acetaldehyde adducts and its characteristics are still vague. To elucidate the binding site of anti-adducts antibody against the epitope on adducts, we established a cell line of hybridoma producing monoclonal antibody. This monoclonal antibody recognized protein condensate modified with high concentration of acetaldehyde (1-10 mM) but not those modified with low concentration of it (20-200 microM), whereas the polyclonal antibody produced by conventional method recognized both of them. Using the affinity-purified adducts by monoclonal or polyclonal antibody-liganded column, we examined the antibody titers by ELISA. The elevation of antibody titer was more specific in chronic alcoholics, especially in patients with hepatic inflammatory change, when antibody was measured against the adducts purified by monoclonal antibody than against the adduct purified by polyclonal antibody. Namely, there exist different types of antibody according to the concentration of acetaldehyde to form the adducts. The concentration of acetaldehyde is thought to be much greater in the liver of alcoholics compared to the patient with non alcoholic liver disease. Actually we have immunohistochemically detected the adduct related to high concentration of acetaldehyde in the liver specimen of alcoholics. In conclusion, the appearance of adduct related to high concentration of acetaldehyde and the acquisition of immunity against it appear to be a characteristic feature in alcoholics with hepatic inflammation. Therefore, evaluation of circulating antibodies against protein epitope related to high concentration of acetaldehyde is helpful to know conditions of such types of liver disease seen in alcoholics.
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PMID:[Immune response against protein epitopes modified with acetaldehyde and its clinical significance in alcoholic liver diseases]. 751 Apr 76

The Long-Evans Cinnamon (LEC) rat is a mutant strain established from Long-Evans rats. LEC rats display hereditary hepatitis and spontaneous hepatocellular carcinoma (HCC). We first tried to examine effects of ethanol consumption on the development of HCC, and fed a Lieber's liquid diet containing 5% ethanol to LEC rats. However the rats died within 2 weeks because of acute alcohol intoxication. In LEC rats, the concentration of ethanol and acetaldehyde in blood was significantly higher, and liver alcohol dehydrogenase activity was slightly lower and acetaldehyde dehydrogenase activities were remarkably suppressed compared to those of Wistar rats. These results suggest that LEC rats have hereditary deficiencies of ethanol and acetaldehyde metabolizing enzymes.
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PMID:Abnormal ethanol metabolism in Long-Evans Cinnamon rats, a mutant strain developing spontaneous hepatoma. 800 22

Alcoholism alone, or in combination with other etiologic factors, is a common cause of liver failure because of hepatitis, cirrhosis, and/or hepatocellular cancer. Encountered morphologic and functional alterations are due to immunologic reactivity to cell injury evoked by acetaldehyde, other noxious factors, and nutrient deficits. Less than 20% of subjects who consume over 90 g/d of ethanol for years develop progressive liver damage and cirrhosis. Alcoholism should be interrupted in patients with subclinical hepatic abnormalities. Although early alcoholic hepatitis and cirrhosis respond to abstinence and symptomatic therapy, available measures have little influence on functional and morphologic abnormalities in end-stage alcoholic liver disease. Resection is desirable for localized hepatocellular cancer, and liver transplantation should be considered for cirrhosis. Transplantation is appropriate for patients with uncomplicated end-stage alcoholic cirrhosis in whom evidence of liver failure can be controlled during a 6-month period of rehabilitation. Continuous psychosocial support is required to prevent recividism in the posttransplant immunosuppressed alcoholic.
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PMID:Alcoholic liver disease. 813 22

We produced hepatitis in guinea pigs by immunization with acetaldehyde adducts and ethanol treatment. Human hemoglobin-acetaldehyde adducts were prepared without any reducing agents and affinity purified with polyclonal antibodies against acetaldehyde adducts. Female guinea pigs were immunized with the adducts and were simultaneously given ethanol for 40 days. These treatments induced hepatic necrosis with infiltration of mononuclear cells in the hepatic lobules. The formation of the lymphoid follicle was also observed in severe cases. These changes were accompanied by the elevation of serum AST and lactic dehydrogenase activities and titers of circulating antibodies against acetaldehyde adducts. By contrast, the combination of ethanol and immunization with unmodified hemoglobin produced only fatty change of the liver, and animals immunized with the adducts alone had minimal inflammatory changes of the liver. Peripheral blood lymphocytes obtained from the animals with hepatitis were shown to be stimulated by acetaldehyde adducts to a significantly greater degree than those from control animals who received nothing, ethanol alone or ethanol and unmodified hemoglobin. These results suggest that the immune response to acetaldehyde adducts may be involved, at least partly, in the pathogenesis of inflammation observed in alcoholic liver disease.
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PMID:Experimental hepatitis induced by ethanol after immunization with acetaldehyde adducts. 842 34

The principal metabolite of ethanol, acetaldehyde, conjugates with various proteins that form antibody-inducing neo-antigens. We have analysed sera from patients with biopsy-proven alcoholic liver disease (hepatitis = 10, cirrhosis = 11, steatosis = 3) and controls = 19 (normal teetotallers and 6 non-alcoholic liver disease). Sera were examined with an enzyme-linked immunoabsorbent assay (ELISA) for antibodies binding preferentially to an acetaldehyde-albumin conjugate. Reactive sera from alcohol misusers were then purified using an amino-hexyl Sepharose affinity column. Antibodies binding to the acetaldehyde-albumin epitopes were significantly raised (P < 0.005) in all groups of alcohol misusers, and were present in greatest titre in those with alcoholic hepatitis. These antibodies were successfully purified using the gel affinity column. We conclude that alcohol misusers have significant titres of antibodies reacting to the acetaldehyde-albumin complex. The role of these antibodies remains nuclear, but may be related to the initiation of an inflammatory response and tissue damage following ethanol consumption.
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PMID:Detection of antibodies to acetaldehyde-albumin conjugates in alcoholic liver disease. 847 Oct 80

The effect of ethanol on cells infected with mouse hepatitis virus (MHV) was investigated. After MHV infection of competent cells, NCTC1469, ethanol was added to the culture at various concentrations, and the viability of cells was measured using 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide. To examine the possible involvement of the ethanol metabolite, acetaldehyde, alcohol dehydrogenase activity was measured in NCTC1469 cells. Ethanol alone did not show cytotoxicity against NCTC1469 cells at concentrations from 0.125% to 2%. After infection with MHV, the viability of cells decreased, and this decrease was further enhanced, dose-dependently, by the addition of ethanol. The activity of alcohol dehydrogenase in the cells was below the detectable level. The same phenomena were also demonstrated in cells infected with influenza virus and Herpes simplex virus. These results demonstrate that ethanol enhances MHV-mediated cytotoxicity; this exacerbation of cytotoxicity by ethanol is suggested to be an effect common to cytopathic virus-infected cells.
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PMID:Effect of ethanol on mouse hepatitis virus-induced cytotoxicity. 888 34

Thus far, a large number of hypothesis have been proposed to explain how ethanol causes liver diseases including fatty liver, hepatitis, hepatic fibrosis, cirrhosis, as well as hepatocellular carcinoma. Although it still remains obscure, recent progress of science enables us to understand the mechanisms more deeply. We reviewed the latest aspects of mechanisms of alcoholic liver diseases, including alteration of redox state, effects of acetaldehyde and acetate, changes of metabolisms of lipid and protein, production of free radicals, alteration of hepatic micro circulation, change of hepatic membrane composition followed by changes of intracellular signal transduction, and effects of endotoxin. Moreover, we discussed the recent progress of studies on enzyme systems which participate in ethanol metabolism.
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PMID:[Recent progression in research on alcoholic liver disease]. 904 44

An acetaldehyde (AcH) adduct was prepared using rabbit low-density lipoprotein as carrier proteins. An antibody against this adduct was raised in Watanabe heritable hyperlipidemic rabbits and cross-reacted with human low-density lipoprotein and bovine serum albumin adducts. Using this antibody, serum anti-AcH-adduct antibody levels were measured by a direct ELISA method in 56 Japanese adults (healthy adults and patients with nonalcoholic gastrointestinal diseases, alcoholic liver injury, or alcoholic pancreatitis). The antibody level (mean +/- SD) was 22 +/- 10 microg/ml in healthy adults, 22 +/- 11 microg/ml in nonalcoholic gastrointestinal diseases, and 16 +/- 13 microg/ml in alcoholic pancreatitis. These antibody levels tended to increase with the progression of alcoholic liver injury, starting from fatty liver via hepatitis to cirrhosis, 29 +/- 24 microg/ml in fatty liver, 35 +/- 29 microg/ml in alcoholic hepatitis, and 46 +/- 54 microg/ml in alcoholic cirrhosis. The antibody level in patients taking 100 g or more of ethanol per day tended to be higher, compared with those in people taking less ethanol. A follow-up observation revealed that alcohol abstinence after hospitalization raised serum anti-AcH-adduct antibody level in some patients and kept it constantly low in other patients. The immunohistochemical study using the anti-AcH-adduct antibody revealed the presence of adduct-like substance in hepatocytes of liver biopsy specimens obtained from patients with alcoholic liver disease. The results indicate that the anti-AcH-adduct antibody may be associated with the progress of alcoholic liver diseases.
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PMID:An enzyme immune assay for serum anti-acetaldehyde adduct antibody using low-density lipoprotein adduct and its significance in alcoholic liver injury. 962 94

Acetaldehyde and malonildialdehyde can form hybrid protein adducts, named MAA adducts that have strong immunogenic properties. The formation of MAA adducts in the liver of chronic alcohol-fed rats is associated with the development of circulating antibodies that specifically recognized these adducts. The aim of this study was to examine whether MAA adducts might participate in the immune response associated with human alcohol-induced liver disease. Circulating antibodies against MAA adducts were evaluated in 50 patients with alcohol-induced hepatitis or cirrhosis, in 40 patients with non-alcohol-induced liver disease, in 15 heavy drinkers without liver damage and in 40 healthy controls by enzyme-linked immunosorbent assays (ELISA). Immunoglobulin G (IgG) reacting with MAA-modified proteins were significantly increased in the patients with alcohol-induced cirrhosis or hepatitis. The individual levels of anti-MAA IgG in those patients were associated with the severity of liver damage. Anti-MAA antibodies were also positively correlated with the levels of IgG recognizing epitopes generated by acetaldehyde and malonildialdehyde. However, competitive inhibition experiments indicated that the anti-MAA antibodies were unrelated to those against acetaldehyde- or malonildialdehyde-derived antigens and mainly recognized a specific, cyclic MAA epitope. Some degree of immune reactivity towards MAA adducts was also observed in patients with non-alcohol-induced liver injury. However, competitive ELISA showed that the antigens recognized by these sera were not the cyclic MAA adducts. Altogether, these results showed the formation of MAA antigens during alcohol-induced liver disease and suggest their possible contribution to the development of immunologic reactions associated with alcohol-related liver damage.
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PMID:Detection of circulating antibodies against malondialdehyde-acetaldehyde adducts in patients with alcohol-induced liver disease. 1073 43


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