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.

Green areas around homes reduce atopic sensitization in children

Background

Western lifestyle is associated with high prevalence of allergy, asthma and other chronic inflammatory disorders. To explain this association, we tested the ‘biodiversity hypothesis’, which posits that reduced contact of children with environmental biodiversity, including environmental microbiota in natural habitats, has adverse consequences on the assembly of human commensal microbiota and its contribution to immune tolerance.

Methods

We analysed four study cohorts from Finland and Estonia (n = 1044) comprising children and adolescents aged 0.5–20 years. The prevalence of atopic sensitization was assessed by measuring serum IgE specific to inhalant allergens. We calculated the proportion of five land-use types – forest, agricultural land, built areas, wetlands and water bodies – in the landscape around the homes using the CORINE2006 classification.

Results

The cover of forest and agricultural land within 2–5 km from the home was inversely and significantly associated with atopic sensitization. This relationship was observed for children 6 years of age and older. Land-use pattern explained 20% of the variation in the relative abundance of Proteobacteria on the skin of healthy individuals, supporting the hypothesis of a strong environmental effect on the commensal microbiota.

Conclusions

The amount of green environment (forest and agricultural land) around homes was inversely associated with the risk of atopic sensitization in children. The results indicate that early-life exposure to green environments is especially important. The environmental effect may be mediated via the effect of environmental microbiota on the commensal microbiota influencing immunotolerance.

Introduction of complementary foods in infancy and atopic sensitization at the age of 5 years: timing and food diversity in a Finnish birth cohort

OBJECTIVE

To study the associations between timing and diversity of introduction of complementary foods during infancy and atopic sensitization in 5-year-old children.

METHODS

In the Finnish DIPP (type 1 diabetes prediction and prevention) birth cohort (n = 3781), data on the timing of infant feeding were collected up to the age of 2 years and serum IgE antibodies toward four food and four inhalant allergens measured at the age of 5 years. Logistic regression was used for the analyses.

RESULTS

Median duration of exclusive and total breastfeeding was 1.4 (interquartile range: 0.2-3.5) and 7.0 (4.0-11.0) months, respectively. When all the foods were studied together and adjusted for confounders, short duration of breastfeeding decreased the risk of sensitization to birch allergen; introduction of oats <5.1 months and barley <5.5 months decreased the risk of sensitization to wheat and egg allergens, and oats additionally associated with milk, timothy grass, and birch allergens. Introduction of rye <7.0 months decreased the risk of sensitization to birch allergen. Introduction of fish <6 months and egg ≤11 months decreased the risk of sensitization to all the specific allergens studied. The introduction of <3 food items at 3 months was associated with sensitization to wheat, timothy grass, and birch allergens; the introduction of 1-2 food items at 4 months and ≤4 food items at 6 months was associated with all endpoints, but house dust mite. These results were particularly evident among high-risk children when the results were stratified by atopic history, indicating the potential for reverse causality.

CONCLUSIONS

The introduction of complementary foods was consecutively done, and with respect to the timing of each food, early introduction of complementary foods may protect against atopic sensitization in childhood, particularly among high-risk children. Less food diversity as already at 3 months of age may increase the risk of atopic sensitization.

Glomerular filtration rate and parathyroid hormone are associated with 1,25-dihydroxyvitamin D in men without chronic kidney disease

BACKGROUND AND AIM

Vitamin D, estimated glomerular filtration rate (eGFR) and parathyroid hormone (PTH) are related to cardiovascular disease risk. We examined the associations between the levels of 25-hydroxyvitamin D (25-D) and 1,25-dihydroxyvitamin D (1,25-D) and both eGFR and PTH.

DESIGN AND SETTING

Cross-sectional population-based study in Kuopio, Eastern Finland.

SUBJECTS

A total of 909 men without known chronic kidney disease (CKD) and not receiving antidiabetic medication, aged from 45 to 73 years, were included in the study. Main outcome measures. Fasting levels of 25-D, 1,25-D, creatinine and PTH were measured, and an oral glucose tolerance test (OGTT) was performed.

RESULTS

High levels of 25-D were associated with low levels of eGFR and PTH (β = -0.17, P = 9 × 10(-7) and β = -0.28, P = 6 × 10(-17) , respectively, adjusted for age, body mass index and levels of calcium, phosphorus and glucose in a 2-h OGTT, and also for either eGFR or PTH). By contrast, high 1,25-D levels were associated with high levels of eGFR and PTH (β = 0.17, P = 2 × 10(-6) and β = 0.19, P = 5 × 10(-8) , respectively, adjusted as mentioned earlier and additionally for 25-D). Eighteen per cent of men in the highest 25-D quartile were in the lowest 1,25-D quartile and also had a lower eGFR than men with high levels of both 25-D and 1,25-D (P = 4 × 10(-5) ). Finally, 15% of men in the lowest 25-D quartile were in the highest 1,25-D quartile and also had higher PTH levels than men with low levels of both 25-D and 1,25-D (P = 2 × 10(-3) ).

CONCLUSION

Our findings suggest that both eGFR and PTH are significantly associated with vitamin D metabolism in men without known CKD.

Diverse associations of 25-hydroxyvitamin D and 1,25-dihydroxy-vitamin D with dyslipidaemias

BACKGROUND AND AIM

Previous studies have suggested a link between circulating levels of 25-hydroxyvitamin D (25-D) and dyslipidaemias. However, it is not known whether 25-D and the active hormone 1,25-dihydroxyvitamin D (1,25-D) have similar associations with dyslipidaemias. Therefore, we studied the associations between both 25-D and 1,25-D and total cholesterol (total-C), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides in a population-based study.

DESIGN

Cross-sectional population-based study.

SETTING

Kuopio, Eastern Finland.

SUBJECTS

A total of 909 men, aged from 45 to 70 years, who were not receiving antidiabetic medication were enrolled.

MAIN OUTCOME MEASURES

Fasting serum samples were obtained for measurement of 25-D, 1,25-D and lipid levels. An oral glucose tolerance test was performed, and insulin sensitivity was evaluated using the Matsuda insulin sensitivity index (Matsuda ISI).

RESULTS

We found a significant inverse association between 25-D and total-C, LDL-C and triglycerides (β = -0.15, -0.13 and -0.17, respectively, P < 0.001), but no association between 25-D and HDL-C was observed. By contrast, 1,25-D was associated with HDL-C (β = 0.18, P < 0.001), whereas no relationship was found between 1,25-D and LDL-C or triglycerides. The associations remained significant after the exclusion of subjects receiving statin treatment and after adjustment for age, waist circumference, body mass index, alcohol consumption, smoking, renal function, glucose tolerance and Matsuda ISI.

CONCLUSION

Low levels of active vitamin D (1,25-D) are associated with low HDL-C levels, whereas low levels of the storage form 25-D are associated with high levels of total-C, LDL-C and triglycerides. Our findings may provide new insights into the understanding of the link between vitamin D deficiency and cardiovascular disease.

Obesity and the clinical use of serum GGT activity as a marker of heavy drinking

OBJECTIVE

Gamma-glutamyl transferase (GGT) is a widely used clinical marker of alcohol abuse. However, although obesity may also elevate serum GGT activities, the effects of overweight on the interpretation of GGT testing have remained poorly defined.

MATERIAL AND METHODS

GGT activities from 1147 moderate drinkers and 449 abstainers who were classified according to body mass index (BMI) were compared with those of 208 heavy drinkers admitted for detoxification.

RESULTS

GGT upper normal limits, defined based on normal weight abstainers (men 53 U/L; women 45 U/L) were lower than those based on moderate drinkers (men 68 U/L; women 50 U/L). The relative increases in GGT activities in male moderate drinkers with overweight (54%) or obesity (125%) exceeded the corresponding changes found in women (25% and 75%, respectively). The BMI-dependent variation on the sensitivity of GGT for correctly classifying heavy drinkers ranged from 29% to 67%. The rates of false-positive values in the subgroups from low to high BMI varied from 0% to 27%, respectively.

CONCLUSIONS

The data indicate that the diagnostic value of serum GGT testing could be improved by using reference data derived from databases of abstainers with normal weight or BMI-based categorization of reference ranges.

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.

Comparison of 99mTc ciprofloxacin, 99mTc white blood cell and three-phase bone imaging in the diagnosis of hip prosthesis infections: improved diagnostic accuracy with extended imaging time

The purpose of this study was to compare the utility of 99mTc labelled ciprofloxacin (Infecton) imaging with the 99mTc white blood cell and three-phase bone imaging procedures for identifying hip prosthesis infection. We studied 30 symptomatic patients in whom infection was confirmed in eight and excluded in 22 cases based on clinical and microbiological findings. 99mTc ciprofloxacin images were obtained at 1, 4 and 24 h after the injection of the tracer, and the data were compared to those obtained from 99mTc leukocyte and three-phase bone imaging. The 99mTc ciprofloxacin imaging correctly identified all true infections. In 13 (59%) of the non-infected patients, non-specific uptake of 99mTc ciprofloxacin was found in the 1-h and 4-h images, which disappeared, however, in the 24-h images. When the early and late 99mTc ciprofloxacin images were compared, the specificity was found to improve from 41% to 95%, positive predictive value from 38% to 89%, and the diagnostic accuracy from 57% to 97%. The accuracy of the conventional 99mTc leukocyte imaging was 90%. Dynamic bone imaging also yielded abnormal findings in all the infected patients although also in 23% of the non-infected patients. Current data indicate that 99mTc ciprofloxacin is a useful method for confirming hip prosthesis infection. The diagnostic efficiency of this method is improved when the imaging time is extended to 24 h post-injection of the tracer.

Elevated serum PIIINP and laminin in inflammatory bowel disease indicate hepatobiliary and pancreatic dysfunction

BACKGROUND/AIMS

Levels of S-PIIINP (serum aminoterminal propeptide of type III procollagen) have been shown to be increased in patients with primary sclerosing cholangitis and inflammatory bowel disease. The aim of the study was to investigate the serum concentrations of PIIINP and laminin in inflammatory bowel disease patients, their relationship with inflammatory bowel disease-associated hepatobiliary and pancreatic dysfunction, and to correlate them with clinical, endoscopic, and histologic variables.

METHODOLOGY

S-PIIINP and S-laminin were measured in 222 consecutive inflammatory bowel disease patients, who were screened for abnormal liver and pancreatic enzymes and for pancreatic exocrine hypofunction with the p-aminobenzoic acid test (215 patients). The patients with abnormal screening results were further scheduled for endoscopic retrograde cholangiopancreatography, liver biopsy, secretin test and ultrasound.

RESULTS

S-PIIINP and S-laminin were abnormally high in 19% and 40% of all inflammatory bowel disease patients, respectively. The elevated levels of the fibrosis markers were associated with laboratory signs of either hepatobiliary or pancreatic disease. Hepatobiliary disease was found in 37 (17%) of inflammatory bowel disease patients, 15 of whom had primary sclerosing cholangitis. The median levels of S-PIIINP and S-laminin were significantly higher in patients with hepatobiliary disease than in those without (P < 0.0001 and P < 0.001, respectively), being most strikingly elevated in primary sclerosing cholangitis. Abnormal pancreatic screening tests were found in 67 (30%) patients. High levels of S-PIIINP and S-laminin were also significantly associated with low values in p-aminobenzoic acid (P < 0.001 and P < 0.005) and secretin (P < 0.01 and P < 0.05) tests, but not with inflammatory bowel disease category, endoscopic or histological disease extent, frequency of bowel resection or actual clinical activity.

CONCLUSIONS

In inflammatory bowel disease, increased S-PIIINP and S-laminin are associated with hepatobiliary and pancreatic disorders.

99m Tc-ciprofloxacin (Infecton) imaging in the diagnosis of knee prosthesis infections

The purpose of this study was to evaluate the usefulness of 99mTc labelled ciprofloxacin imaging in detecting the presence of infection in patients with symptomatic knee prostheses. Among 16 randomly selected patients of whom seven had infection based on clinical and microbiological findings and nine did not, 99mTc-ciprofloxacin images were obtained at 1, 4 and 24h after the injection of the tracer. While there was some diffuse non-specific accumulation of 99mTc-ciprofloxacin in large synovial joints and in prosthetic knee joints, the infected knee prostheses were found to show more intensive focal uptake, which also extended outside the synovial cavity. The infection related uptake remained visible in the 24h images, whereas non-specific uptake had a fading tendency at this time point. 99mTc-ciprofloxacin imaging showed diagnostic sensitivity of 86% and a specificity of 78% for correctly classifying the presence of infection. The data indicate that 99mTc-ciprofloxacin imaging may be used in the diagnosis of knee prosthesis infections. Infection-related uptake remains visible in the 24h images and is typically found also outside the synovial cavity, which should be noted in the evaluation of the images.

Distribution of ethanol-induced protein adducts in vivo: relationship to tissue injury

Generation of oxygen free radicals and reactive aldehydes as a result of excessive ethanol consumption has been well established. Recent studies in human alcoholics and in experimental animal models have indicated that acetaldehyde, the first metabolite of ethanol, and the aldehydic products of lipid peroxidation can bind to proteins in tissues forming stable adducts. The demonstration of such adducts in zone 3 hepatocytes in alcoholics with an early phase of histological liver damage indicates that adduct formation may have an important role in the sequence of events leading to alcoholic liver disease. There may be interference with cellular functions, stimulation of fibrogenesis, and immunological responses. Autoantibodies towards distinct types of adducts have been shown to be associated with the severity of liver disease in alcoholic patients. High fat diet and/or iron supplementation combined with ethanol may increase the amount of aldehyde-derived epitopes and promote fibrogenesis in the liver. Recently, ethanol-derived protein modifications have also been found from other tissues exposed to ethanol and acetaldehyde, including rat brain after lifelong ethanol administration, pancreas, and rat muscle. Elevated adduct levels also occur in erythrocytes of alcoholics, which may be related to ethanol-induced morphological aberrations in hematopoiesis.

Molecular aspects of iron absorption and HFE expression

Hereditary hemochromatosis, a disease of iron overload, occurs in about 1 in 200-400 Caucasians. The gene mutated in this disorder is termed HFE. The product of this gene, HFE protein, is homologous to major histocompatibility complex class I proteins, but HFE does not present peptides to T cells. Based on recent structural, biochemical, and cell biological studies, transferrin receptor (TfR) is a ligand for HFE. This association directly links HFE protein to the TfR-mediated regulation of iron homeostasis. Although evidence is accumulating that binding of HFE to TfR is critical for the effects of HFE, the final pieces in the HFE puzzle have not been established. This review focuses on recent advances in HFE research and presents a hypothetical model of HFE function.

Assays for acetaldehyde-derived adducts in blood proteins based on antibodies against acetaldehyde/lipoprotein condensates

BACKGROUND

Acetaldehyde-derived protein condensates (adducts) have been suggested as promising biological markers of alcohol abuse because they represent actual metabolites of ethanol. However, the detection of such condensates in vivo has been hampered by a lack of sensitive and specific methods.

METHODS

To develop new approaches for the detection of acetaldehyde adducts, we have raised antibodies against condensates with acetaldehyde and lipoproteins, which have previously been shown to be readily modified by acetaldehyde in vitro. The characteristics of these antibodies were compared with those raised against bovine serum albumin/acetaldehyde adduct and against other types of lipoprotein modifications, as induced by malondialdehyde, oxidation, and acetylation.

RESULTS

The antibodies raised against low-density lipoprotein (LDL)/acetaldehyde, very low density lipoprotein (VLDL)/acetaldehyde, and bovine serum albumin/acetaldehyde all reacted with protein adducts generated at physiologically relevant concentrations of acetaldehyde in vitro, whereas the antibodies raised against malondialdehyde/LDL, oxidized LDL, or acetylated LDL were not found to cross-react with the acetaldehyde-derived adducts. In assays for acetaldehyde adducts from erythrocyte and serum proteins of patients with excessive ethanol consumption (n = 32) and healthy control individuals (n = 22), the antibody prepared against the acetaldehyde/VLDL condensate was found to provide the most effective detection of acetaldehyde adducts in vivo.

CONCLUSIONS

Current data indicate that acetaldehyde generates immunogenic adducts with lipoproteins in vivo. Antibodies raised against the VLDL/acetaldehyde may provide a basis for new diagnostic assays to examine excessive alcohol consumption.

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.

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.

Acetaldehyde adducts in blood and bone marrow of patients with ethanol-induced erythrocyte abnormalities

BACKGROUND

Although alcohol abuse is known to cause a wide array of adverse effects on blood cell formation, the molecular mechanisms by which alcohol exerts its toxic actions remain poorly defined. We examine here the formation of acetaldehyde-derived protein modifications in erythrocytes and in their bone marrow precursors using antibodies specifically recognizing acetaldehyde-modified epitopes in proteins independently of the nature of the carrier protein.

MATERIALS AND METHODS

We studied 138 consecutive adult patients undergoing bone marrow aspiration due to macrocytosis (MCV values above 99 fL). Assessment included complete blood counts, morphologic review, assessment of alcohol consumption, and biochemical and immunocytochemical assays for acetaldehyde adducts.

RESULTS

There were 68 patients (49%) with a history of excessive alcohol consumption, 28 (20%) of whom were patients with severe dependence. The blood smears prepared from the alcoholic patients with macrocytosis also contained stomatocytes and knizocytes. Bone marrow aspirates from 12 alcoholic patients showed vacuolization of pronormoblasts and the presence of ring sideroblasts was noted in 8 cases. In immunocytochemical analyses of the peripheral blood erythrocytes, acetaldehyde-derived epitopes were found to occur both on the cell membrane and inside the erythrocytes. Bone marrow aspirates also showed positive staining for acetaldehyde adducts in the erythropoietic cells in 8 of 11 (73%) consecutive alcoholic patients. Separation of the erythrocyte proteins from the samples of alcoholics on HPLC-chromatography revealed the formation of fast-eluting hemoglobin fractions, which also reacted with antibodies against acetaldehyde adducts.

CONCLUSIONS

Current data suggest that acetaldehyde-erythrocyte adducts are formed in vivo in blood and bone marrow of patients with excessive alcohol consumption. This may contribute to the generation of the erythrocyte abnormalities, which are frequently observed in alcoholic patients.

Extended combined 99mTc-white blood cell and bone imaging improves the diagnostic accuracy in the detection of hip replacement infections

Although the diagnosis of hip prosthesis infection is clinically important, X-ray studies, blood chemistry and synovial fluid aspiration may be unreliable for this purpose. The aim of this study was to evaluate whether extending the time for technetium-99m labelled leucocyte imaging to 24 h post injection improves the accuracy of diagnosis of hip replacement infections. We studied 64 symptomatic patients with hip prostheses. The presence of infections was verified by intraoperative bacterial cultures, and infection was excluded either by negative operative findings or by follow-up for at least 1 year. Leucocyte imaging was done with 99mTc-hexamethylpropylene amine oxime (HMPAO)-labelled leucocytes at 2-4 h (routine images) and at 24 h (late images) after the injection of the leucocytes. In addition, bone imaging was carried out with 99mTc-hydroxydiphosphonate (HDP) at the arterial, soft tissue and metabolic phases. A standardised method was used to compare leucocyte images with bone metabolic images. In this material, there were six confirmed infections. All the bone imaging methods had a sensitivity of 100% in detecting prosthesis infections whereas the specificity varied from only 2% to 82%. Routine leucocyte imaging was less sensitive (50% vs 83%) and less specific (90% vs 100%) than late leucocyte imaging. All tests had a high negative predictive value for excluding infection (95%-100%). However, both bone (10%-38%) and routine leucocyte imaging (33%) showed a poor positive predictive value (PPV), whereas late leucocyte imaging had a PPV of 100% and a diagnostic accuracy of 98%. We conclude that late leucocyte imaging improves the specificity of diagnosis of infected hip prostheses. This type of imaging procedure should be combined with three-phase bone scintigraphy in studies of patients with painful joint replacement.

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.

Cytochromes P450 2A6, 2E1, and 3A and production of protein-aldehyde adducts in the liver of patients with alcoholic and non-alcoholic liver diseases

BACKGROUND/AIMS

Interaction between CYP2E1, ethanol metabolites, and enhanced lipid peroxidation is linked to the pathogenesis of alcoholic liver disease. This study was conducted to compare the expression of various cytochrome enzymes and the appearance of aldehyde adducts in humans.

METHODS

Acetaldehyde- and lipid peroxidation-derived protein adducts and CYP2A6, 2E1, and 3A4/5 were examined immunohistochemically from liver specimens of 12 alcohol abusers with either mild (n=7) or severe (n=5) liver disease, and from nine non-drinking patients with non-alcoholic steatosis (n=4), or hepatitis (n=5).

RESULTS

Ethanol-inducible CYP2E1 was present in all alcoholic livers. While CYP2A6 in zone 3 hepatocytes was also abundant in the alcoholic patients with various degrees of liver disease, CYP3A415 was most prominent in alcoholic cirrhosis. The sites of CYP2E1 and CYP2A6 immunoreactivity co-localized with fatty deposits, and with the sites of acetaldehyde and lipid peroxidation-derived protein adducts. The CYP enzymes were also abundant in the centrilobular hepatocytes of patients with fatty liver due to obesity or diabetes.

CONCLUSIONS

Alcohol-induced liver damage is associated with a generalized induction of CYP2A6, CYP2E1 and CYP3A4 and generation of acetaldehyde and lipid peroxidation-derived protein-aldehyde adducts. However, CYP induction also occurred in patients with non-alcoholic steatosis.

Covalent adducts of proteins with acetaldehyde in the liver as a result of acetaldehyde administration in drinking water

BACKGROUND/AIMS

Acetaldehyde, the first metabolic product of ethanol, has been suggested to be responsible for several adverse effects of ethanol through its ability to form covalent adducts with proteins and cellular constituents. It has recently been suggested that acetaldehyde derived from microbial ethanol oxidation in the gut could also contribute to the effects of ethanol in the liver. The present work aimed to examine whether modification of proteins by acetaldehyde occurs in rat liver as a result of acetaldehyde administration in drinking water.

METHODS

Rats were fed with either 0.7% acetaldehyde (n=10) or water (n=10) for 11 weeks. At the end of the feeding period, liver specimens were processed for immunohistochemistry for protein adducts with acetaldehyde and for hepatic cell type-specific protein markers.

RESULTS

Mild fatty change was found in the liver of the acetaldehyde-treated animals but not in the control animals. Immunohistochemical stainings for acetaldehyde adducts revealed intensive positive staining for acetaldehyde adducts in eight (80%) of the animals fed with acetaldehyde. The adducts were predominantly perivenular, although positive staining also occurred along the sinusoids and in the periportal area. Double immunofluorescence staining experiments revealed that hepatocytes were the primary targets of acetaldehyde adduct deposition, although stellate cells and Kupffer cells also showed weak positive reactions.

CONCLUSIONS

The present data indicate that acetaldehyde-protein adducts are formed in the liver of animals following acetaldehyde administration in drinking water, which may contribute to the hepatotoxicity of extrahepatic acetaldehyde. These findings should be implicated in studies on the extrahepatic pathways of ethanol oxidation.

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.

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.

Mean cell volume and gamma-glutamyl transferase are superior to carbohydrate-deficient transferrin and hemoglobin-acetaldehyde adducts in the follow-up of pregnant women with alcohol abuse

BACKGROUND AND OBJECTIVE

To compare the usefulness of carbohydrate-deficient transferrin (CDT), the ratio of CDT to total transferrin, and hemoglobin-acetaldehyde adducts with mean cell volume (MCV) and gamma-glutamyl transferase (GGT) in the follow-up of alcohol abuse during pregnancy.

METHODS

Forty-four pregnant drug and alcohol abusing female patients attending a special outpatient clinic were followed from the 8th to 24th gestational week onwards. A population of sixty-two healthy pregnant women was recruited to assess the effect of gestation on the markers.

RESULTS

Eight of thirteen heavy drinking (> or =8 drinks/week) patients delivered infants with fetal alcohol effects (FAE). MCV and GGT were higher among heavy drinking patients than in moderately drinking (<8 drinks/week) patients (92+/-4 vs 90+/-3 fl and 31+/-34 vs 16+/-10 U/ L, respectively), and in patients delivering infants with FAE compared with patients delivering healthy infants (95+/-3 vs 90+/-3 fl and 34+/-26 vs 15+/-10 U/L, respectively). Hemoglobin-acetaldehyde adducts, CDT, and the ratio of CDT to total transferrin were neither associated with the reported level of alcohol consumption nor with the occurrence of FAE. In the receiver operating characteristics analysis MCV was found to be superior to CDT and the adducts, and GGT superior to the adducts, in identifying heavy drinking and in predicting FAE. In the control population, both CDT and total transferrin were found to rise during pregnancy, whereas the ratio of CDT to total transferrin was found to decline. The upper reference range of 33 U/L for CDT was considerably higher than that of non-pregnant women (26 U/L).

CONCLUSION

MCV and GGT appear to be the most efficient laboratory markers for detecting excessive alcohol consumption and the adverse effects of alcohol on the fetus.

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.

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.

Aldehyde-protein adducts in the liver as a result of ethanol-induced oxidative stress

A number of systems that generate oxygen free radicals and reactive aldehydic species are activated by excessive ethanol consumption. Recent studies from human alcoholics and from experimental animals have indicated that acetaldehyde and aldehydic products of lipid peroxidation, which are generated in such processes, can bind to proteins forming stable adducts. Adduct formation may lead to several adverse consequences, such as interference with protein function, stimulation of fibrogenesis, and induction of immune responses. The presence of protein adducts in the centrilobular region of the liver in alcohol abusers with an early phase of histological liver damage indicates that adduct formation is one of the key events in the pathogenesis of alcoholic liver disease. Dietary supplementation with fat and/or iron strikingly increases the amount of aldehyde-derived epitopes in the liver together with promotion of fibrogenesis.

Hepatic lipid peroxidation in hereditary hemochromatosis and alcoholic liver injury

Studies in experimental animals have indicated that enhanced lipid peroxidation may play a role in the hepatic injury produced by iron overload or by excessive alcohol consumption. The aim of this study was to compare the formation of lipid peroxidation-derived aldehydes in the liver of patients with hereditary hemochromatosis (HH) and alcohol abuse. Liver biopsy specimens from 10 nondrinking patients with HH were evaluated. These patients were classified as having HH based on hepatic iron index or human leukocyte antigen identity with a known proband. All patients were homozygous for the Cys282Tyr mutation. In addition, 8 patients with alcoholic liver disease were examined, 2 of whom also had hemochromatosis. For comparison, 17 patients with liver diseases unrelated to iron overload or alcohol abuse were studied. Liver biopsy specimens were immunostained for protein adducts with malondialdehyde and 4-hydroxynonenal. Both malondialdehyde- and 4-hydroxynonenal-protein adducts were found from liver specimens of patients with HH and alcohol abuse in more abundant amounts than from patients in a control group. In alcoholics the adducts were primarily in zone 3, whereas in hemochromatosis staining had an acinar zone 1 predominance, which followed the localization of iron. The most abundant amounts of protein adducts were noted in patients with alcohol abuse plus iron overload. The data support the concept that both chronic alcohol use and iron overload induce hepatic lipid peroxidation. Through formation of reactive aldehydic products, excessive alcohol consumption and iron overload may have additive hepatotoxic effects.

Dopamine transporters increase in human brain after alcohol withdrawal

Dopaminergic transmission has been suggested to be a main mechanism mediating reinforcement, withdrawal and craving associated with alcohol addiction. We measured here striatal dopamine (DA) transporter binding from 27 alcoholics within 4 days after cessation of prolonged heavy drinking and after a 4-week period of abstinence with single photon emission computed tomography (SPECT) using a cocaine analogue, iodine-123-beta-CIT. Controls were 29 healthy volunteers. Blind quantitative analyses of the SPECT data revealed markedly lower DA transporter binding in alcoholics on admission for detoxification than in the non-alcoholic controls. After a 4-week period of abstinence DA transporter binding increased significantly in the alcoholics (P<0.0001) reaching the levels of the healthy controls. The most substantial recovery in DA transporter binding occurred during the first 4 days of abstinence. The data indicate that prolonged heavy drinking decreases DA transporter binding and disturbs synaptic dopamine transport. This may sensitize alcoholics to dopaminergic transmission, which may lead to early relapse after ethanol withdrawal.

Early alcoholic liver injury: formation of protein adducts with acetaldehyde and lipid peroxidation products, and expression of CYP2E1 and CYP3A

The formation of protein adducts with reactive aldehydes resulting from ethanol metabolism and lipid peroxidation has been suggested to play a role in the pathogenesis of alcoholic liver injury. To gain further insight on the contribution of such aldehydes in alcoholic liver disease, we have compared the appearance of acetaldehyde, malondialdehyde, and 4-hydroxynonenal adducts with the expression of cytochrome P-450IIE1, and cytochrome P-4503A enzymes in the liver of rats fed alcohol with a high-fat diet for 2 to 4 weeks according to the Tsukamoto-French procedure and in control rats (high-fat liquid diet or no treatment). Urine alcohol and serum aminotransferase levels were recorded, and the liver pathology was scored from 0 to 10 according to the presence of steatosis, inflammation, necrosis, and fibrosis. The ethanol treatment resulted in the accumulation of fat, mild necrosis and inflammation, and a mean liver pathology score of 3 (range: 1 to 5). Liver specimens from the ethanol-fed animals with early alcohol-induced liver injury were found to contain perivenular, hepatocellular acetaldehyde adducts. Malondialdehyde and 4-hydroxynonenal adducts were also present showing a more diffuse staining pattern with occasional sinusoidal reactions. In the control animals, a faint positive reaction for the hydroxynonenal adduct occurred in some of the animals fed the high fat diet, whereas no specific staining was observed in the livers from the animals receiving no treatment. Expression of both CYP2E1 and CYP3A correlated with the amount of protein adducts in the liver of alcohol-treated rats. Distinct CYP2E1-positive immunohistochemistry was seen in 3 of 7 of the ethanol-fed animals. In 5 of 7 of the ethanol-fed animals, the staining intensities for CYP3A markedly exceeded those obtained from the controls. The present findings indicate that acetaldehyde and lipid peroxidation-derived adducts are generated in the early phase of alcohol-induced liver disease. The formation of protein adducts appears to be accompanied by induction of both CYP2E1 and CYP3A.

Comparison of the Axis %CDT TIA and the CDTect method as laboratory tests of alcohol abuse

Carbohydrate-deficient transferrin (CDT) has been suggested as a specific marker of alcohol abuse. We designed this study to compare the conventional CDTect method (Pharmacia & Upjohn) and the new semiautomated Axis %CDT turbidimetric immunoassay (%CDT TIA) for their diagnostic performance to identify problem drinking. The sensitivities of the %CDT TIA and CDTect for correctly classifying heavy drinkers (n = 90) were 29% and 59% with the thresholds currently recommended by the manufacturers, respectively. In the control group (n = 114), which included hospitalized patients with abnormal serum transferrin concentrations, the CDTect assay gave 21 false-positive values (18%), whereas the %CDT TIA showed 100% specificity. With the cutoff limits based on the present healthy control group (mean + 2 SD), the sensitivities of the %CDT TIA and CDTect were 61% and 86%, respectively. For men, the ROC plot area of the CDTect results in comparisons of alcohol abusers and healthy controls was significantly (P < 0.05) higher than that of the %CDT TIA results, whereas for women, there was no significant difference in this respect. The slope and intercept (with 95% confidence intervals) for linear regression between CDTect and %CDT TIA were 0.13 (0.12-0.15) and 1.16 (0.73-1.59), respectively (S(y/x) = 1.51, r = 0.744). CDTect results correlated positively with serum transferrin (r = 0.224, P < 0.001), whereas the %CDT TIA results showed a slight inverse correlation with serum transferrin (r = -0.132, P = 0.07). The data suggest that CDTect is more sensitive than %CDT TIA in detecting drinking problems. However, the %CDT TIA method yields more specificity when analyzing samples from patients with high serum transferrin concentrations.

Serum IgA, IgG, and IgM antibodies directed against acetaldehyde-derived epitopes: relationship to liver disease severity and alcohol consumption

Chronic ethanol ingestion has been suggested to trigger the formation of antibodies that recognize acetaldehyde-protein condensates. In this study, assays for immunoglobulin (Ig) A, IgG, and IgM antibodies to acetaldehyde-derived adducts were performed on sera of 140 alcohol consumers, 19 patients with nonalcoholic liver disease (NALD), 35 healthy nondrinking controls, and 10 nondrinking patients with IgA or IgG myeloma. Anti-acetaldehyde (Ach)-adduct antibodies of each Ig isotype were found from the alcohol abusers. In alcoholic liver disease (ALD, n = 86) IgA titers were elevated in 69% of the patients. These titers were significantly higher than those from patients with NALD (P < .001), nondrinking controls (P < .001), or heavy drinkers (n = 54) without any clinical and biochemical signs of liver disease (P < .001). In contrast, anti-adduct IgG titers were significantly elevated both in ALD and in heavy drinkers as compared with patients with NALD (P < .001) or nondrinking controls (P < .01 and P < .05, respectively). The anti-adduct immunoglobulin (Ig)A, IgG, and IgM titers in patients with alcoholic liver disease (ALD) correlated with the combined clinical and laboratory index of liver disease severity (r(s) = .497, P < .001; r(s) = .361, P < .01; and r(s) = .322, P < .01). Anti-adduct IgA titers also correlated with serum bilirubin (r = .768, P < .001) and interleukin 6 (r = .504, P < .001). Anti-adduct IgG titers were, in turn, found to correlate with the presence of inflammation (P < .01) and necrosis (P < .01). During follow-up studies of individual patients, parallel changes were observed in the anti-adduct IgG titers, disease severity, and serum markers of fibrogenesis. The present results provide evidence that antibodies representing distinct Ig classes directed against acetaldehyde (Ach)-derived adducts of proteins are formed in alcoholic patients showing an association with the severity of liver disease. The follow-up data also support an association between such immune responses and the aggravation 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.

Carbonic anhydrase II in the cerebrospinal fluid: its value as a disease marker

Carbonic anhydrase (CA) II is the predominant CA isoenzyme in the brain of mammals. We have recently developed a dual-label time-resolved immunofluorometric assay to quantify minute amounts of CA I and II in the cerebrospinal fluid (CSF). The present study was aimed at elucidating the clinical value of such measurements in the case of neurological disorders. Lumbar CSF samples were obtained from 111 patients suffering from various neurological diseases and from 97 control patients with no specific signs of central nervous system diseases. The highest CA II concentrations were found in patients with brain infarction (median 66.5 micrograms L-1, n = 20), whereas the control patients had markedly lower values (median 7.8 micrograms L-1, n = 97). Relative to a reference range calculated from the control material (10.2 +/- 17.2 micrograms L-1), the sensitivity of CA II measurement in differentiating brain infarction was 100%. Patients with transient ischaemic attack (median 11.2 micrograms L-1, n = 9), multiple sclerosis (median 14.7 micrograms L-1, n = 18) or epilepsy (median 20.3 micrograms L-1, n = 17) usually had CA II concentrations within the normal range, but those with central nervous system infection (n = 14), dementia (n = 19) or trigeminal neuralgia (n = 6) tended to have higher CA II levels in their CSF, the median values being 39.1 micrograms L-1, 45.5 micrograms L-1 and 44.0 micrograms L-1 respectively. The findings indicate that the concentration of CA II in the CSF marks disease activity in patients with brain damage. This finding could provide a basis for further studies estimating the value of CA II measurement as a new laboratory marker of diseases affecting the brain.

Iron overload in the rat pancreas following portacaval shunting and dietary iron supplementation

Reproduction of pancreatic iron overload in an animal model has been difficult to achieve primarily because of the first-pass extraction of iron by the liver. We hypothesized that portacaval shunting would avoid this hepatic phenomenon and increase pancreatic iron deposition. An end-to-side portacaval shunt was surgically created in male Sprague-Dawley rats, and they were subsequently fed a carbonyl iron-supplemented diet for 17 weeks. This resulted in marked iron accumulation in the pancreas (1621 +/- 188 micrograms/g) compared to minimal deposition in sham-operated rats fed the same diet (138 +/- 53 micrograms/g). Iron deposition in the acinar and centroacinar cells was confirmed histologically by Gomori staining, as well as by ultrastructural examination. Iron overloading was associated with enhanced oxidative stress evidenced by a twofold increase in the levels of glutathione disulfide and thiobarbituric acid-reactive substances. Also, adducts of proteins with malondialdehyde and 4-hydroxynonenal were demonstrated in acinar and ductal cells. Other apparent consequences of iron overload were a 50% reduction in pancreatic amylase content and a decrease in pancreatic protein concentration. These hypotrophic changes were associated with a reduced mass of zymogen granules in the acinar cells noted histologically. Our results show that a combination of portacaval shunting and carbonyl iron feeding achieve pancreatic iron overload and support the role of oxidative stress in the pathogenesis of iron-induced damage in the pancreas.

Sensitivity and specificity of carbohydrate-deficient transferrin as a marker of alcohol abuse are significantly influenced by alterations in serum transferrin: comparison of two methods

Despite a number of investigations suggesting the value of carbohydrate-deficient transferrin (CDT) as a marker of alcohol abuse, a variety of issues on the applicability of CDT measurements in clinical settings have remained unexplored. Earlier studies in this field have focused on the relationship of CDT and the amount of alcohol consumption or presence of liver disease, whereas the influence of alterations in serum transferrin concentrations on CDT has received less attention. In this study, we compared two different methods for measuring CDT (CDTect and %CDT) and total transferrin concentrations in a sample of 83 alcohol abusers (20 patients with alcoholic liver disease and 63 heavy drinkers who were devoid of liver disease, despite excessive alcohol consumption) and 89 controls, who were social drinkers or abstainers. The control population included 53 hospitalized patients with expected abnormalities in serum transferrin concentrations caused by conditions such as negative iron balance, pregnancy, or nonalcoholic liver disease. Both methods gave significantly higher values in alcohol abusers than in controls (p < 0.01), but the overall sensitivity for detecting alcohol abuse was clearly higher for CDTect (59%) than for %CDT (34%). The correlation between the results obtained by the two methods (r = 0.629) significantly improved, when the CDTect values were replaced by the ratio of CDTect/total transferrin (r = 0.770) (p < 0.05). There was a positive correlation between the CDTect and serum transferrin (r = 0.201, p < 0.01), which was significant both in the alcoholics (r = 0.240, p < 0.05), and especially in the controls (r = 0.727, p < 0.001). A significant inverse correlation emerged between %CDT and total transferrin (r = -0.302, p < 0.01). The sensitivities of CDTect and %CDT for correctly classifying alcohol abusers in the subgroup of alcoholic liver disease patients were 90% and 70% and in the subgroup of heavy drinkers without liver disease (49% and 22%), respectively. Specificities for CDTect and %CDT in this sample were 81% and 100%, respectively. However, in the subgroup of hospitalized control patients with abnormal serum transferrin, the specificity of CDTect was only 48%. According to present data, CDTect seems to be more sensitive than %CDT for detecting alcohol abuse. However, any alteration in serum total transferrin concentration markedly decreases the assay specificity. This should be considered when interpreting the assay results in patients with elevated serum transferrin, such as iron deficiency, pregnancy, or liver diseases.

Vitamin E decreases hepatic levels of aldehyde-derived peroxidation products in rats with iron overload

Hepatic iron overload can cause lipid peroxidation with the formation of aldehydic products, hepatocellular injury, and fibrosis. Vitamin E (alpha-tocopherol) may prevent peroxidation-induced hepatic damage. We used confocal laser scanning microscopy, digital image analysis, and immunohistochemical methods to quantitate aldehyde-derived peroxidation products in the liver of rats with experimental iron overload with or without supplemental vitamin E. A strong autofluorescent reaction colocalizing with iron deposits was present in the livers of iron-loaded rats. Fluorescent granules were unevenly distributed in the cytosol of both hepatocytes and Kupffer cells in the periportal regions. Immunohistochemical studies revealed the presence of malon-dialdehyde adducts in the periportal regions of the ironloaded rats. Vitamin E supplementation markedly reduced the fluorescence intensity and the amount of aldehyde-derived peroxidation products and changed the distribution of stainable iron and iron-associated peroxidation products such that their levels were much decreased in Kupffer cells. These results indicate that aldehyde-derived covalent chemical addition products are formed in the liver in iron overload. Vitamin E supplementation markedly reduces the amount of these compounds and changes their cellular distribution. These findings should be implicated in the role of antioxidant therapy in conditions causing iron overload and lipid peroxidation.

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)

Sequential acetaldehyde production, lipid peroxidation, and fibrogenesis in micropig model of alcohol-induced liver disease

The pathogenesis of alcohol-induced liver disease involves the adverse effects of ethanol metabolites and oxidative tissue injury. Previous studies indicated that covalent protein adducts with reactive aldehydes may be formed in alcohol consumers. To study the role of such protein adducts in the development of liver injury, we examined the sequential appearances of adducts of the ethanol metabolite acetaldehyde (AA) and of two products of lipid peroxidation, malondialdehyde (MDA) and 4-hydroxynonenol (HNE), in ethanol-fed micropigs. Immunohistochemical stainings using specific antibodies that recognize epitopes of each adduct were performed from liver biopsy specimens obtained at 1, 5, and 12 months from micropigs fed either control diet (n = 5) or ethanol-containing diets (n = 5). After 1 month on the ethanol diet, AA and MDA adducts were observed primarily in the perivenous regions co-localizing with each other and coinciding with increased concentrations of serum aminotransferase markers of liver injury. HNE adducts were usually less intense and more diffuse, and were also seen in some biopsy specimens from control animals. Although the most intense staining reactions at 5 months remained in zone 3, a more widespread distribution was usually seen together with increased evidence of steatonecrosis and focal inflammation. In terminal biopsies at 12 months, perivenous fibrosis was present in three of five biopsy specimens. More extensive pericentral and intralobular fibrosis was noted in one micropig fed ethanol for 21 months. These studies demonstrate that covalent adducts of proteins with reactive aldehydes are formed in early phases of alcohol-induced liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Sequential acetaldehyde production, lipid peroxidation, and fibrogenesis in micropig model of alcohol-induced liver disease

The pathogenesis of alcohol-induced liver disease involves the adverse effects of ethanol metabolites and oxidative tissue injury. Previous studies indicated that covalent protein adducts with reactive aldehydes may be formed in alcohol consumers. To study the role of such protein adducts in the development of liver injury, we examined the sequential appearances of adducts of the ethanol metabolite acetaldehyde (AA) and of two products of lipid peroxidation, malondialdehyde (MDA) and 4-hydroxynonenol (HNE), in ethanol-fed micropigs. Immunohistochemical stainings using specific antibodies that recognize epitopes of each adduct were performed from liver biopsy specimens obtained at 1, 5, and 12 months from micropigs fed either control diet (n = 5) or ethanol-containing diets (n = 5). After 1 month on the ethanol diet, AA and MDA adducts were observed primarily in the perivenous regions co-localizing with each other and coinciding with increased concentrations of serum aminotransferase markers of liver injury. HNE adducts were usually less intense and more diffuse, and were also seen in some biopsy specimens from control animals. Although the most intense staining reactions at 5 months remained in zone 3, a more widespread distribution was usually seen together with increased evidence of steatonecrosis and focal inflammation. In terminal biopsies at 12 months, perivenous fibrosis was present in three of five biopsy specimens. More extensive pericentral and intralobular fibrosis was noted in one micropig fed ethanol for 21 months. These studies demonstrate that covalent adducts of proteins with reactive aldehydes are formed in early phases of alcohol-induced liver disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Roles of oxidative stress in activation of Kupffer and Ito cells in liver fibrogenesis

An increasing body of experimental evidence is emerging to incriminate oxidative stress as a pivotal signal for liver fibrogenesis. This paper reviews the results from our studies testing this hypothesis. In the rat model of alcoholic liver disease, the importance of oxidative stress was supported by marked accentuation of liver fibrosis by dietary supplementation of iron, a pro-oxidant, and the significant correlation of the liver malondialdehyde (MDA) and 4-hydroxynonenal (4HNE) levels with the hepatic collagen accumulation. Both MDA and 4HNE adduct epitopes were detected intensely and diffusely in close association with collagen deposition. The direct cause and effect relationship between MDA/4HNE and Ito cell stimulation was indicated by the demonstration of Ito cell collagen gene induction by these aldehydes in culture. In primary cultures of rat Kupffer cells (KC), addition of antioxidants such as alpha-tocopherol acetate and succinate suppressed mRNA expression and the release of interleukin (IL)-6 and tumour necrosis factor alpha (TNF alpha). In rats with biliary fibrosis, an increase in the liver MDA level was accompanied by enhanced mRNA expression of procollagen alpha 1(I) and transforming growth factor beta 1 in Ito cells; and that of TNF alpha and IL-6 in KC. Furthermore, the gel shift assay of KC nuclear extracts showed enhanced NF-kB DNA binding activity. These results support the proposal that enhanced oxidative stress constitutes an important signal for activation of Kupffer and Ito cells in experimental liver fibrogenesis.

Experimental liver cirrhosis induced by alcohol and iron

To determine if alcoholic liver fibrogenesis is exacerbated by dietary iron supplementation, carbonyl iron (0.25% wt/vol) was intragastrically infused with or without ethanol to rats for 16 wk. Carbonyl iron had no effect on blood alcohol concentration, hepatic biochemical measurements, or liver histology in control animals. In both ethanol-fed and control rats, the supplementation produced a two- to threefold increase in the mean hepatic non-heme iron concentration but it remained within or near the range found in normal human subjects. As previously shown, the concentrations of liver malondialdehyde (MDA), liver 4-hydroxynonenal (4HNE), and serum aminotransferases (ALT, AST) were significantly elevated by ethanol infusion alone. The addition of iron supplementation to ethanol resulted in a further twofold increment in mean MDA, 4HNE, ALT, and AST. On histological examination, focal fibrosis was found < 30% of the rats fed ethanol alone. In animals given both ethanol and iron, fibrosis was present in all, with a diffuse central-central bridging pattern in 60%, and two animals (17%) developed micronodular cirrhosis. The iron-potentiated alcoholic liver fibrogenesis was closely associated with intense and diffuse immunostaining for MDA and 4HNE adduct epitopes in the livers. Furthermore, in these animals, accentuated increases in procollagen alpha 1(I) and TGF beta 1 mRNA levels were found in both liver tissues and freshly isolated hepatic stellate cells, perisinusoidal cells believed to be a major source of extracellular matrices in liver fibrosis. The dietary iron supplementation to intragastric ethanol infusion exacerbates hepatocyte damage, promotes liver fibrogenesis, and produces evident cirrhosis in some animals. These results provide evidence for a critical role of iron and iron-catalyzed oxidant stress in progression of alcoholic liver disease.

High-activity carbonic anhydrase isoenzyme (CA II) in human gallbladder epithelium

Acidification of bile is one of the factors that prevents calcium precipitation and thereby gallstone formation. Carbonic anhydrase II (CA II) has previously been shown to be one of the key factors in the human alimentary tract that regulates the acid-base balance. We demonstrated CA II expression in the human gallbladder epithelium using immunohistochemical techniques, elucidated the CA II content of the epithelium by digital image analysis of the immunohistochemically stained enzyme in samples from 16 patients undergoing cholecystectomy, and correlated the results with the calcium content of the gallstones. Nine patients had symptomatic gallstone disease and seven an acalculous, histologically normal gallbladder. The patients were classified into two groups on the basis of the calcium content of their gallstones: no gallstones or gallstones containing no calcium (Group 1) and gallstones with 2-87% calcium by weight (Group 2). The immunohistochemical techniques showed distinct epithelial CA II-positive staining in most of the gallbladder samples, but digital image analysis revealed distinct variations in staining intensity among them. The median staining intensity index was significantly higher in Group 1 (0.4463) than in Group 2 (0.2376; p = 0.0262). The results suggest that CA II is abundantly expressed in the normal gallbladder epithelium and that decreased expression may be associated with the formation of calcified gallstones. These findings are relevant to the pathogenesis of gallstone disease.

Characteristics of symptomatic gallbladder disease in patients with either solitary or multiple cholesterol gallstones

Recent studies have indicated that solitary or multiple gallstones may differ with respect to the conditions favoring their formation, such as nucleation time. We examined the clinical, histological and laboratory characteristics of symptomatic gallstone disease in a series of 125 consecutive patients with either solitary (n = 33) or multiple (n = 92) cholesterol gallstones undergoing cholecystectomy. The nature of biliary pain was found to differ in the two groups. Histological diagnoses of acute cholecystitis and gallbladder cancer was more frequent in the patients with multiple stones, and cholesterolosis in those with solitary stones. Furthermore, the stone cholesterol content was higher in the solitary stone group than in the multiple stone group. Morbid complications such as cholangitis and pancreatitis were rare and occurred only in the multiple stone group. The results support the view that gallbladder disease presents histological evidence of biliary complications more often in patients with multiple cholesterol stones than in those with solitary stones.

Covalent protein adducts in the liver as a result of ethanol metabolism and lipid peroxidation

BACKGROUND

The primary mechanisms of ethanol-induced tissue damage have been suggested to include aldehyde-derived protein modifications resulting from ethanol metabolism and lipid peroxidation. Conjugation of reactive aldehydes to a variety of target proteins and cellular constituents have been recently reported. This research was undertaken in order to examine the presence of covalent chemical addition products (adducts) of proteins and acetaldehyde, the first metabolite of ethanol, and those with malondialdehyde, a product of lipid peroxidation, as formed in vivo.

EXPERIMENTAL DESIGN

Specific antibodies recognizing acetaldehyde- and malondialdehyde-modified epitopes in proteins were used in immunoperoxidase and double immunofluorescence stainings of liver specimens obtained from ethanol-fed rats and micropigs and from human alcoholics.

RESULTS

The centrilobular region of the liver contained the protein modifications both in alcohol-consuming humans and in animals fed ethanol before any apparent histologic damage. With inflammation and fibrosis, such protein modifications were more widespread, and the positive staining for the malondialdehyde-derived modification became more dominant. The presence of the adducts colocalized with the areas of fatty infiltration, focal necrosis and fibrosis. In addition, the erythrocytes of alcohol consumers were found to contain such modifications.

CONCLUSIONS

The studies support the view that covalent damage to proteins and cellular constituents induced by aldehyde-derived modifications in vivo may play a role in the sequence of events leading to liver disease in alcohol consumers. Species and dietary differences may be important in the relative contribution of lipid peroxidation to alcohol-induced tissue damage.

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.

Segmental mediolytic arteritis--electronmicroscopic and immunohistochemical study

We examined specimens of human gastroepiploic artery aneurysm from a patient having several visceral aneurysms using electronmicroscopic and immunohistochemical techniques. The histopathological and ultrastructural findings confirmed the diagnosis of segmental mediolytic arteritis. Arterial smooth muscle cells from the gastroepiploic artery contained cytoplasmic vacuoles, media was thin and the internal elastic membrane showed distortion. X-ray microanalysis revealed calcium deposits in the medial extracellular space. Antigenic determinants of human immunoglobulins, fibrinogen, complement C3a and factor VIII were demonstrated in the injured artery wall, suggesting that immunocomplexes deposited in the artery wall may be associated with local injury. These findings support the role of autoimmune disorders in the pathogenesis of segmental mediolytic arteritis.

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.