Centrilobular distribution of acetaldehyde and collagen in the ethanol-fed micropig

We established a new animal model of alcoholic liver disease in the micropig, a species that consumes ethanol voluntarily in the diet. Ten micropigs were pair-fed diets containing 40% of calories as ethanol or cornstarch with identical amounts of fat, protein and micronutrients for 12 mo. Liver histopathology in the ethanol-fed pigs included steatonecrosis in all five and interstitial and perivenous fibrosis in three. Electron microscopy showed Ito-cell transformation with perisinusoidal collagen accumulation. Acetaldehyde adducts were found by immunofluorescence in the centrilobular region and were focused in perivenous zone 3 of all ethanol-fed animals. Protein and triglyceride levels were increased, whereas vitamin A and iron levels were decreased in liver homogenates from ethanol-fed animals. Thus, in this new animal model of alcoholism, ethanol feeding produced the features of alcoholic liver disease concurrent with hepatic deficiency of selected nutrients. Histological and immunofluorescent studies provide in vivo evidence that perivenous collagen deposition is linked to ethanol metabolism and acetaldehyde production.

Hemoglobin-acetaldehyde adducts in human volunteers following acute ethanol ingestion

Rabbit antibodies against albumin-acetaldehyde adduct were used in an enzyme-linked immunosorbent assay to detect acetaldehyde-hemoglobin condensates from the blood of 12 volunteers following ingestion of 1.3 to 2.9 g of ethanol per kg body weight during 8 hr. Blood samples were drawn before drinking and between 2 to 46 hr after starting the drinking session. While there were no significant increases in blood acetaldehyde levels in these samples, acetaldehyde-hemoglobin adducts were significantly increased in the samples drawn after ethanol had been eliminated from the body. Administration of ethanol (0.1 g/kg) to an Oriental flusher resulted in an increase both in blood acetaldehyde and the hemoglobin-acetaldehyde adduct levels. These results suggest that acetaldehyde-hemoglobin condensates are formed in vivo following acute ethanol ingestion. Such condensates may be of value to mark alcohol consumption.

Autoimmune responses against oxidant stress and acetaldehyde-derived epitopes in human alcohol consumers

BACKGROUND

Studies in experimental animals have indicated that chronic ethanol ingestion triggers the formation of antibodies directed against proteins modified with reactive metabolites of ethanol and products of lipid peroxidation. However, the nature and prevalence of such antibodies have not been compared previously in alcoholic patients.

METHODS

Autoantibodies against adducts with acetaldehyde- (AA), malondialdehyde- (MDA), and oxidized epitopes (Ox) were examined from sera of 54 alcohol consumers with (n = 28) or without (n = 26) liver disease, and from 20 nondrinking controls.

RESULTS

Anti-AA-adduct IgA and IgG antibodies were elevated in 64% and 31% of patients with biopsy-proven alcoholic liver disease (ALD, n = 28), respectively. The IgA titers were significantly higher than those from nondrinking controls (p < 0.001), or heavy drinkers without significant liver disease (p < 0.001). Anti-MDA adduct titers (IgG) were elevated in 70% of the ALD patients. These titers were significantly higher (p < 0.001) than those from nondrinking controls, or heavy drinkers without liver disease. Antibodies (IgG) against Ox epitopes occurred in 43% of ALD patients, and the titers also were significantly higher (p < 0.05) than those from nondrinking controls. The anti-AA and anti-MDA adduct titers in ALD patients correlated significantly with the combined clinical and laboratory index (CCLI) of liver disease severity (r(s) = 0.449, p < 0.05; r(s) = 0.566, p < 0.01, respectively), the highest prevalences of anti-AA-adducts (73%) and anti-MDA-adducts (76%) occurring in ALD patients with cirrhosis.

CONCLUSIONS

The present results indicated that autoantibodies against several distinct types of protein modifications are generated in ALD patients showing an association with the severity of liver disease.

Role of iron in NF-kappa B activation and cytokine gene expression by rat hepatic macrophages

A redox-sensitive nuclear factor, NF-kappa B, induces transcription of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in macrophages. The present study has investigated the role of iron in NF-kappa B activation and TNF-alpha and IL-6 expression by rat hepatic macrophages (HM). As an in vivo model, cholestatic liver injury was induced in rats by ligation of the common bile duct (BDL). During the first 2 wk after BDL, there was an increase in the hepatic level of thiobarbituric acid-reactive substances (TBARS) that was accompanied by the appearance of protein-malondialdehyde adducts in the periportal region. This increase was reduced after 3 wk. TNF-alpha and IL-6 mRNA levels in HM from the BDL rats were increased at 1 and 2 wk and attenuated at 3 wk. Gel mobility shift assay of HM nuclear extracts demonstrated the similar temporal pattern of enhanced NF-kappa B binding activity. Treatment of the BDL animals with 1,2-dimethyl-3-hydroxypyrid-4-one (L-1), a lipophilic iron chelator, suppressed the increases in hepatic TBARS by 64%, plasma alanine aminotransferase by 45%, and HM TNF-alpha and IL-6 mRNA by > 84%. Concomitantly, the HM NF-kappa B binding activity was reduced close to the level observed in sham-operated rats. Treatment of cultured HM with L-1 also blocked lipopolysaccharide-stimulated NF-kappa B activation and TNF-alpha and IL-6 expression at mRNA and protein levels. These results demonstrate that the iron chelator effectively blocks NF-kappa B activation and coordinate TNF-alpha and IL-6 gene upregulation by HM in cholestatic liver injury or under in vitro lipopolysaccharide stimulation. These findings support a pivotal role for iron in activation of NF-kappa B and cytokine gene expression by HM in vitro and in vivo.

Carbohydrate-deficient transferrin as a marker of alcohol abuse: relationship to alcohol consumption, severity of liver disease, and fibrogenesis

Carbohydrate-deficient transferrin (CDT) measurements have been widely examined as a marker of excessive alcohol consumption, yet the information on the sensitivity of this method has remained controversial. In addition, little is known of the relationship of this marker and the severity of alcoholic liver disease (ALD). To clarify these issues, we analyzed serum samples from 373 alcohol abusers, including 200 problem drinkers with no apparent liver pathology, 173 patients with clinical or morphological evidence of ALD, and 42 healthy controls. CDT was analyzed by anion-exchange chromatography followed by radioimmunoassay. At a specificity of 100%, the sensitivity of CDT was 36% in problem drinkers reporting a mean of 710 +/- 80 (mean +/- 2SE) g of ethanol/week, as compared with the sensitivities of 44% and 35% for gamma-glutamyltranspeptidase (GGT) and mean corpuscular volume (MCV), respectively. In a subgroup of problem drinkers (n = 51) with the highest ethanol intakes (1160 +/- 180 g of ethanol/week) and severe dependence, the sensitivity of CDT increased to 64%, compared with 55% for GGT and 39% for MCV. In ALD, the CDT values were significantly higher than in the alcoholics with nonliver pathology. However, when such patients were classified according to the clinical, laboratory, and morphological severity of liver disease, CDT was found to be primarily elevated in those with the early stage of ALD, such that there was a significant negative correlation between CDT and the combined morphological index of disease severity (rs = -0.315, p < 0.05). ALD markers of fibrogenesis were elevated more frequently than CDT, showing significant positive correlations with the indices of disease severity.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral trauma and alcohol abuse

We report results of clinical examinations, computed tomography, quantitative electroencephalography (QEEG), and cerebral blood flow measurements performed on a series of 56 consecutive brain injury patients including 15 alcohol abusers and 41 non-alcoholic subjects. Greater volumes of intracranial haemorrhage were noted in the alcoholics for a similar severity of injury and local brain atrophy became more pronounced in them during a follow-up of 1 year. After this time, the third ventricle width, distance between frontal horns, the sum of lateral ventricle dimensions and cortical sulci were all markedly larger in the alcoholics. The QEEG results also indicated a weaker improvement in the alcoholics. The cerebral blood flow at the site of the injury was initially slow in the alcoholics when compared to the contralateral region of the other hemisphere, although these differences disappeared during the follow-up. Permanent occupational disability was also found to be associated with pretraumatic alcohol abuse. The findings indicate that ethanol abuse is not only commonly associated with cerebral trauma but is also a risk factor for a more severe brain damage following the injury.

HFE mutations do not account for transfusional iron overload in patients with acute myeloid leukemia

BACKGROUND

Hereditary hemochromatosis (HH) is a HFE gene-linked disorder affecting 1 of 200 to 400 persons in white populations. It has been proposed that patients with a hematologic malignancy who are receiving frequent RBC transfusions should be screened for HFE mutations. This would identify C282Y homozygotes, who have a high risk of developing severe iron overload.

STUDY DESIGN AND METHODS

DNA samples from 128 controls and 23 adult long-term survivors of acute myeloid leukemia (AML) treated at the Oulu University Hospital (Oulu, Finland) from 1987 to 2000 were examined for the presence of the C282Y and H63D mutations in HFE. All the patients were severely iron-overloaded, as determined from high serum ferritin values and/or increased storage iron in bone marrow. Phlebotomies were performed in five patients because of the symptoms of iron overload. DNA extracted from the blood was used to amplify HFE gene fragments by the PCR method, after which the amplification products were digested with restriction endonucleases SnaB I and Bcl I, and the restriction fragments were analyzed on agarose gels.

RESULTS

No chromosomes with the C282Y mutation were found among the AML patients, and 5 patients (21.7%) were heterozygous for the H63D mutation. In the control group, 13 persons (10.2%) were heterozygous for the C282Y mutation and 26 (20.3%) for the H63D mutation, including 3 C282Y/H63D double heterozygotes.

CONCLUSION

HFE mutations do not account for the harmful iron overload that develops in AML patients who receive large quantities of RBC concentrates after intensive chemotherapy.

Induction of cytochrome P450 enzymes and generation of protein-aldehyde adducts are associated with sex-dependent sensitivity to alcohol-induced liver disease in micropigs

To assess possible links between ethanol-induced oxidant stress, expression of hepatic cytochrome P450 (CYP) enzymes, and sex steroid status, we used immunohistochemical methods to compare the generation of protein adducts of acetaldehyde (AA), malondialdehyde (MDA), and 4-hydroxynonenal (4-HNE) with the amounts of CYP2E1, CYP2A, and CYP3A in the livers of castrated and noncastrated male micropigs fed ethanol for 12 months. In castrated micropigs, ethanol feeding resulted in accumulation of fat, hepatocellular necrosis, inflammation, and centrilobular fibrosis, whereas only minimal histopathology was observed in their noncastrated counterparts. CYP2A and CYP3A were more prominent in the castrated animals than in the noncastrated micropigs. Ethanol feeding increased the hepatic content of all CYP forms. The most significant increases occurred in CYP2E1 and CYP3A in the noncastrated animals and in CYP2E1 and CYP2A in the castrated animals. Ethanol-fed castrated animals also showed the greatest abundance of perivenular adducts of AA, MDA, and HNE. In the noncastrated ethanol-fed micropigs a low expression of each CYP form was associated with scant evidence of aldehyde-protein adducts. Significant correlations emerged between the levels of different CYP forms, protein adducts, and plasma levels of sex steroids. The present findings indicate that the generation of protein-aldehyde adducts is associated with the induction of several cytochrome enzymes in a sex steroid-dependent manner. It appears that the premature, juvenile, metabolic phenotype, as induced by castration, favors liver damage. The present findings should be implicated in studies on the gender differences on the adverse effects of ethanol in the liver.

Radioimmunoassays for type III procollagen amino-terminal peptides in humans

Use of radioimmunoassay for the amino-terminal propeptide of type III procollagen for monitoring fibrotic processes in humans has been frustrating because of the nonparallel relation between results for the standard bovine antigen and human serum samples. In the radioimmunoassays I developed for this propeptide and its monomeric Col 1 domain, based on use of antigens from humans, serum samples generated less-steep inhibition curves than did the standard antigen in the propeptide assay; in the Col 1 assay, however, serum and urine samples both generated inhibition curves having the same slope as that generated with the standard Col 1 peptide. Concentrations of human fragment Col 1 in serum samples as measured with the Col 1 assay were usually double those obtained with the human propeptide assay, which in turn were two- to threefold those obtained with the bovine antigen assay. In control subjects and alcoholic cirrhotics the concentrations of antigen in urine and the daily excretion rates as measured with the assay for human Col 1 exceeded those reported previously. The presence of different antigen forms was demonstrated with both assays by gel-filtration analysis of serum and urine samples. The assay for human Col 1 should be suitable for routine clinical chemical use.

Evidence of acetaldehyde-protein adduct formation in rat brain after lifelong consumption of ethanol

Acetaldehyde, the first metabolite of ethanol, has been shown to be capable of binding covalently to liver proteins in vivo, which may be responsible for a variety of toxic effects of ethanol. Acetaldehyde-protein adducts have previously been detected in the liver of patients and experimental animals with alcoholic liver disease. Although a role for acetaldehyde as a possible mediator of ethanol-induced neurotoxicity has also been previously suggested, the formation of protein-acetaldehyde adducts in brain has not been examined. This study was designed to examine the occurrence of acetaldehyde-protein adducts in rat brain after lifelong ethanol exposure. A total of 27 male rats from the alcohol-preferring (AA) and alcohol-avoiding (ANA) lines were used. Four ANA rats and five AA rats were fed 10-12% (v/v) ethanol for 21 months. Both young (n = 10) and old (n = 8) rats receiving water were used as controls. Samples from frontal cortex, cerebellum and liver were processed for immunohistochemical detection of acetaldehyde adducts. In four (two ANA, two AA rats) of the nine ethanol-exposed rats, weak or moderate positive reactions for acetaldehyde adducts could be detected both in the frontal cortex and cerebellum, whereas no such immunostaining was found in the remaining five ethanol-treated rats or in the control rats. The positive reaction was localized to the white matter and some large neurons in layers 4 and 5 of the frontal cortex, and to the molecular layer of the cerebellum. Interestingly, the strongest positive reactions were found among the ANA rats, which are known to display high acetaldehyde levels during ethanol oxidation. We suggest that acetaldehyde may be involved in ethanol-induced neurotoxicity in vivo through formation of adducts with brain proteins and macromolecules.

Spontaneous intraabdominal haemorrhage caused by segmental mediolytic arteritis in a patient with systemic lupus erythematosus--an underestimated entity of autoimmune origin?

We describe the sixth known case of segmental mediolytic arteritis and the third in a survivor. A 70-year-old woman had intraabdominal bleeding due to a ruptured aneurysm of the omental artery. Interestingly, this patient also had a systemic lupus erythematosus. This report gives further support to the role of immune abnormalities underlying segmental mediolytic arteritis.

Fibrotic process and drug metabolism in alcoholic liver disease

The effect of fibrosis on drug metabolism in alcoholic liver disease was evaluated in a comparison of the concentrations of serum aminoterminal propeptide of type III procollagen and basement membrane (BM; 7S domain of type IV collagen and laminin) antigens with in vitro (cytochrome P-450) and in vivo (antipyrine) drug metabolism in 67 alcoholics classified by liver histology. Alcoholics with intact or fatty liver had rapid or normal drug metabolism and normal collagen metabolism. Alcoholics with a fatty liver plus fibrosis or active cirrhosis had reduced drug metabolism and elevated levels of serum markers for collagen and BM metabolism. Alcoholics with inactive cirrhosis who had received therapy with enzyme inducers had a tendency toward normal drug and collagen metabolism parameters. Antipyrine metabolism, but not P-450 content, was related to the levels of serum type III collagen and BM markers. The fibrotic process, especially BM formation, creates a mechanical barrier that may prevent contact between blood and hepatocytes, thus delaying substrate availability.

Acetaldehyde adducts of proteins: diagnostic and pathogenic implications in diseases caused by excessive alcohol consumption

Alcohol abuse and alcoholism continue to be a major threat to human health. Given their increasing incidence and the detrimental impact on society, it is actually surprising that no objective, specific indicators for the early detection of alcohol-related health problems are available. A diagnostic test for a disease involving excessive alcohol consumption should be extremely specific in order to achieve positive predictive power, and: ideally it should also be very sensitive in order to identify problem drinkers in broad screening programs. The present research indicates that such a test for alcohol abuse may be provided by measurements of covalent chemical addition products (adducts) of acetaldehyde with biologically stable macromolecules. It was recently demonstrated that proteins modified with acetaldehyde are formed in vivo and can induce an antibody response as a result of alcohol consumption. Monoclonal and polyclonal antibodies raised by immunizations against acetaldehyde-modified proteins recognize acetaldehyde adducts irrespective of the nature of the carrier protein. Use of such antibodies in sensitive two-site immunoenzymatic or immunofluorometric assays has indicated that high acetaldehyde adduct concentrations exist in the erythrocytes of alcohol abusers, in healthy volunteers after a bout of drinking, and also in alcohol consuming mothers who subsequently give birth to children with foetal alcohol effects. We have developed the first immunohistochemical techniques for the detection of acetaldehyde adducts in human tissues. The centrilobular region of the liver of alcohol abusers with an early stage of histological tissue damage was found to contain acetaldehyde-modified epitopes, whereas the adducts were more widespread in advanced liver disease. The diagnostic superiority of acetaldehyde adducts as markers of ethanol consumption is due to the fact that they represent true metabolites of ethanol and allow estimations of past alcohol consumption after the ethanol has been eliminated from the body. Investigations into the formation of acetaldehyde adducts in alcohol consumers do not only have diagnostic applications but also help to explain the pathogenesis of alcohol-induced organ damage. Many types of hypersensitivity and immune responses are brought about by acetaldehyde-modified proteins. In addition, such metabolites of ethanol also aggravate liver disease through disturbed protein function and stimulation of fibrogenesis.

Improved method for detecting knee replacement infections based on extended combined 99mTc-white blood cell/bone imaging

The purpose of this study was to evaluate whether an extension of the imaging time to 24 h post-injection improves the diagnostic accuracy of technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) leucocyte imaging in detecting knee replacement infections. Thirty patients were studied, with infection confirmed in eight (27%) and excluded in 22 on the basis of clinical and microbiological findings. Leucocyte imaging was carried out at 2-4 h (routine images) and at 24 h (late images) post-injection. For comparison, bone imaging with technetium-99m-hydroxydiphosphonate (99mTc-HDP) was carried out at arterial, soft tissue and metabolic phases. Late leucocyte imaging was found to be more sensitive (100% vs. 87.5%) and more specific (82% vs. 77%) than routine leucocyte imaging in detecting infections. All the bone imaging methods showed a sensitivity of 100%, whereas the specificity varied from only 5% to 23%. All procedures had high negative predictive values (NPVs) (94 to 100%) for excluding infection. However, the positive predictive value (PPV) was only 28 to 32% for bone imaging and 58% for routine leucocyte imaging, whereas late leucocyte imaging showed a PPV of 67% and a diagnostic accuracy of 87%. The data indicate that late leucocyte imaging may be superior to routine leucocyte imaging for examining patients with symptomatic knee replacements.

Serum basement membrane and type III procollagen-related antigens in primary biliary cirrhosis

A characteristic histological lesion in early primary biliary cirrhosis (PBC) is disruption of the basement membrane around small bile ducts, which at later stages of the disease is followed by fibrosis. To assess the significance of serum basement membrane- and type III procollagen-related antigens in reflecting such processes, we have measured radioimmunologically the concentrations of serum laminin, type IV collagen and the aminoterminal propeptide of type III procollagen in 22 patients with PBC, classified into four stages according to liver histology. The mean laminin concentration in PBC patients was twice that of the healthy control subjects. Increased concentrations were observed in all patients with stage III or IV of the disease and also in 60% (6/10) of the patients, with early stages (I or II). Elevated serum type IV collagen concentrations were found only in four patients, all in the late, fibrotic stages of the disease. The basement membrane protein changes in serum were in accordance with immunohistochemical findings obtained with the antibodies against these proteins. Neither of these serum parameters emerged, however, as a significant predictive factor for survival. The changes in serum aminoterminal propeptide of type III procollagen resembled those in laminin P1. Moreover, the propeptide was also significant as a predictive factor for survival.

Incorporation of sulphate into type III procollagen by cultured human fibroblasts. Identification of tyrosine O-sulphate

Confluent cultures of normal human skin fibroblasts were labelled overnight with [35S]sulphate, and the incorporation of the isotope into type III procollagen, secreted into the medium, was verified by radioimmunoassay and immunoprecipitation after removing the heavily sulphated proteoglycans by anion-exchange chromatography. Type III procollagen and its pro and pN alpha chains were visualized in fluorographs of the immunoprecipitates. The labelled procollagen could be isolated by a combination of ion-exchange chromatography and gel filtration and was found to contain tyrosine O-sulphate, which was identified by thin-layer electrophoresis after Ba(OH)2 hydrolysis. The regions sulphated in the type III procollagen molecule were susceptible to pepsin digestion. Digestion with purified bacterial collagenase at +37 degrees C produced a labelled fragment that was recognized by antibodies against the aminoterminal propeptide of type III procollagen, indicating that the sulphated tyrosine residues are located either in this propeptide or in the non-helical telopeptide region of the type III collagen molecule proper. Sulphation of tyrosine residues is a new post-translational modification in procollagen, which could be involved in the regulation of the processing of type III procollagen into collagen and thus affect the formation of collagen fibres.

Hemoglobin-acetaldehyde adducts are elevated in women carrying alcohol-damaged fetuses

Alcohol use exceeding 3 to 5 daily drinks is associated with a 30% to 50% risk of delivering a child with fetal alcohol effects (FAE). FAE could be prevented if women were counseled and if they decreased their drinking. Therefore, we need sensitive and specific markers to detect alcohol abuse during pregnancy. We investigated whether acetaldehyde-hemoglobin adducts (Hb-Ach) could be such a marker. Using an antiserum specific for acetaldehyde-generated epitopes in proteins, we measured the levels of Hb-Ach from the red cells of 19 women visiting the outpatient department of pregnant alcohol abusers and from 14 nonpregnant controls. The pregnant women were carefully followed to receive personal antenatal care and intensive counseling on alcohol. Nevertheless, eight of the women delivered infants with FAE. The remaining 11 women had healthy infants, although only four of them stopped drinking totally. The highest concentrations of Hb-Ach were found from women who subsequently delivered children with FAE. When compared with the pregnant women abstaining from ethanol the Hb-Ach values were found to be elevated in five of eight (63%) of the women who gave birth to children with FAE, whereas only in two/seven (28%) of the mothers who despite drinking delivered healthy children. Hb-Ach measurements during pregnancy may prove to be useful to monitor the compliance of women withdrawing from alcohol and to distinguish the mothers at risk of affected offspring. The studies also support a pathophysiological role of acetaldehyde in producing ethanol-associated fetal injury.

Covalent binding of acetaldehyde to type III collagen

Incubation of neutral salt soluble type III pN-collagen with [14C]acetaldehyde in vitro resulted in the formation of spontaneously stable acetaldehyde-protein adducts. This reaction occurred primarily at lysine residues and it was not affected by 0.2-2 mM concentrations of ascorbate but addition of sodiumcyanoborohydride increased the stable adducts by 3-5-fold. When confluent cultures of human skin fibroblasts were incubated with physiologically relevant concentrations of acetaldehyde, it became covalently bound to type III procollagen secreted into the medium. We propose that acetaldehyde binding to collagen fibrils occurs in vivo following chronic alcohol consumption.

Expression of testosterone-dependent enzyme, carbonic anhydrase III, and oxidative stress in experimental alcoholic liver disease

We studied the sequential immunohistochemical appearance of androgen-dependent carbonic anhydrase (CA III) during the development of ethanol-induced liver injury using liver samples from castrated and noncastrated male micropigs. In castrated micropigs, the baseline expression of CA III was either low or absent, while distinct positive immunoreactions were found in zone 3 hepatocytes at 5 and 12 months after the initiation of the ethanol diet. The CA III enzyme and protein adducts of lipid peroxidation-derived aldehydic products, malondialdehyde and 4-hydroxynonenal, appeared together in the perivenous region, suggesting that the enzyme functions in an oxidative environment. The positive staining became more abundant and widespread during the progression of alcoholic liver disease. After 12 months, CA III was significantly more abundant in both the ethanol-fed noncastrated and castrated micropigs than in the control animals (P < 0.001, P < 0.05, respectively). CA III content was strikingly high in the ethanol-fed noncastrated animals, consistent with a potential role of androgens in the regulation of ethanol-induced CA III expression. The strongly positive CA III immunoreactions in the ethanol-fed noncastrated micropigs were associated with scant evidence of aldehydic protein adducts and minimal histopathology. Thus, enhanced expression of CA III during ethanol consumption may also account in part for gender differences in the susceptibility for alcohol-induced liver injury.

Biomarkers of alcohol consumption in patients classified according to the degree of liver disease severity

OBJECTIVE

In the search for optimal biomarkers of excessive drinking, only a few studies have been conducted to compare the relationships between ethanol consumption, liver status, and various laboratory markers of ethanol-induced diseases.

MATERIAL AND METHODS

Concentrations of carbohydrate-deficient transferrin (%CDT and CDTect methods), serum sialic acid (SA), gamma-glutamyl transferase (gamma-GT), aspartate aminotransferase (ASAT), mean corpuscular volume (MCV), and a marker of fibrogenesis (PIIINP) were studied in 102 alcoholics with (n=59) or without (n=43) alcoholic liver disease. Controls were 34 healthy volunteers who were either social drinkers or abstainers.

RESULTS

Although concentrations of all markers were significantly higher in the alcoholic patients than in the healthy controls, their diagnostic characteristics showed a considerable degree of variation. The %CDT, SA, and MCV showed the strongest correlations with the amount of recent alcohol intake. The presence of liver pathology notably influenced the results of CDTect, GT, ASAT, and PIIINP. In ROC analyses, the highest rates of diagnostic accuracy for detecting hazardous drinking were reached with GT (0.94), CDT (0.86), and SA (0.85), followed by MCV (0.79) and ASAT (0.77). Upon abstinence, the estimated times for normalization varied between 10 days (CDTect) and 25 days (GT).

CONCLUSIONS

Our data suggest distinct differences in the clinical characteristics of biological markers of ethanol consumption. While the overall accuracy of CDT and GT appear to be highest in the detection of problem drinking, serum SA and PIIINP measurements are of further value when the effects of liver pathology and ethanol drinking need to be differentiated.

Serum IgG and IgE antibodies against mold-derived antigens in patients with symptoms of hypersensitivity

BACKGROUND

Exposure to mold in water-damaged buildings has been suggested to be responsible for various health problems such as hypersensitivity and upper respiratory tract diseases. However, only little information is available on possible diagnostic tools for examining mold-associated health problems.

METHODS

We used recently developed immunofluorometric IgG and IgE assays (UniCAP) to examine serum IgG and IgE antibodies against mold-derived allergens from 70 mold-exposed individuals with (n = 55) or without (n = 15) symptoms of sensitization. Controls were healthy individuals (n = 31) without any history of such exposure.

RESULTS

The IgG titers exceeded the upper normal limits of control individuals (mean +/- 2 S.D.) in 35% of symptomatic men and in 25% of women. The IgG titers were usually higher in women than in men (P < 0.05) showing no significant association with the severity of symptoms. During follow-up of eight mold-exposed subjects for 9-12 months the IgG titers remained relatively constant. Elevated anti-mold IgEs were found in six (11%) of the exposed subjects who were all symptomatic.

CONCLUSIONS

Measurements of anti-mold IgGs may help to confirm exposure in patients with hypersensitivity symptoms and evidence of mold growth in living or working environment. Some exposed symptomatic patients present IgE-mediated responses. Combined measurements of IgGs and IgEs may prove to be of value in the comprehensive assessment and treatment of such patients.

Impairment of histone H1 DNA binding by adduct formation with acetaldehyde

Incubation of histone H1 with pharmacologically relevant concentrations of acetaldehyde resulted in the formation of spontaneously stable acetaldehyde-protein linkages. The reaction of acetaldehyde and H1 purified from rat liver either by a DNA recognition site affinity chromatography or by perchloric acid extraction occurred primarily at the lysine residues in the carboxyterminal tail of H1, which is crucial for its function as a eukaryotic repressor. It was further shown using an H1-lacZ fusion protein produced in E. coli and the protein isolated from rat liver that the formation of acetaldehyde adducts with H1 impair its DNA binding properties. We propose that such a reaction may occur in vivo and lead to an inability to repress genes in the liver upon excessive alcohol consumption. This mechanism may play a role in acetaldehyde-induced collagen synthesis in alcoholics.

Primary aldosteronism: Higher volume load, cardiac output and arterial stiffness than in essential hypertension

BACKGROUND

The diagnostics of primary aldosteronism (PA) are usually carried out in patients taking antihypertensive medications. We compared haemodynamics between medicated PA, medicated essential hypertension (EH), never-medicated EH and normotensive controls (n = 130 in all groups).

METHODS

The hypertensive groups were matched for age (53 years), sex (84 male/46 female) and body mass index (BMI) (30 kg m^-2 ); normotensive controls had similar sex distribution (age 48 years, BMI 27 kg m^-2 ). Haemodynamics were recorded using whole-body impedance cardiography and radial pulse wave analysis, and the results were adjusted as appropriate. Radial blood pressure recordings were calibrated by brachial blood pressure measurements from the contralateral arm.

RESULTS

Radial and aortic systolic and diastolic blood pressure was similar in PA and never-medicated EH, and higher than in medicated EH and normotensive controls (P ≤ 0.001 for all comparisons). Extracellular water balance was ~ 4% higher in PA than in all other groups (P < 0.05 for all), whilst cardiac output was ~ 8% higher in PA than in medicated EH (P = 0.012). Systemic vascular resistance and augmentation index were similarly increased in PA and both EH groups when compared with controls. Pulse wave velocity was higher in PA and never-medicated EH than in medicated EH and normotensive controls (P ≤ 0.033 for all comparisons).

CONCLUSIONS

Medicated PA patients presented with corresponding systemic vascular resistance and wave reflection, but higher extracellular water volume, cardiac output and arterial stiffness than medicated EH patients. Whether the systematic evaluation of these features would benefit the clinical diagnostics of PA remains to be studied in future.