The comparison of total bile acid concentration and alcohol dehydrogenase activity as markers of intrahepatic cholestasis of pregnancy

Introduction: Intrahepatic cholestasis of pregnancy (ICP) is the liver disorder in the second or early third trimester of pregnancy. It is characterized by pruritus with increased serum bile acids concentration and other liver function tests. ICP is connected with increased risk of fetal mortality, but is unfortunately detected quite late. Therefore, it is important to recognize the disease in its early stages. We aimed to investigate the serum alcohol dehydrogenase (ADH) activity and compare it with the concentration of total bile acid (TBA) in women with ICP. Methods: Serum samples were taken for routine investigation from 80 pregnancies with ICP in the second or third trimester of pregnancy and from 80 healthy pregnant women in the same time of pregnancy. For measurement of class I activity we used the spectrofluorometric methods. The total ADH activitiy was measured by the photometric method. Results: The analysis of results shows a statistically significant increase in the activity of ADH I and ADH total (about 60% and 41.3%, respectively). Activity of ADH I well correlated with aminotransferases (alanine ALT and aspartate AST) and total bile acids (TBA) concentration. The total ADH activity was also positively correlated with ALT, AST and total bile acids. Conclusion: We can state that the activity of class I alcohol dehydrogenase isoenzyme in the sera of patients with ICP is increased and seems to be a good indicator of liver cell destruction during this disease and is comparable with the value of other markers.

Metabolic Flow of C6 Volatile Compounds From LOX-HPL Pathway Based on Airflow During the Post-harvest Process of Oolong Tea

Aroma is an essential quality indicator of oolong tea, a tea derived from the Camellia sinensis L. plant. Carboxylic 6 (C6) acids and their derivative esters are important components of fatty acid (FA)-derived volatiles in oolong tea. However, the formation and regulation mechanism of C6 acid during postharvest processing of oolong tea remains unclear. To gain better insight into the molecular and biochemical mechanisms of C6 compounds in oolong tea, a combined analysis of alcohol dehydrogenase (ADH) activity, CsADH2 key gene expression, and the FA-derived metabolome during postharvest processing of oolong tea was performed for the first time, complemented by CsHIP (hypoxia-induced protein conserved region) gene expression analysis. Volatile fatty acid derivative (VFAD)-targeted metabolomics analysis using headspace solid-phase microextraction–gas chromatography time-of-flight mass spectrometry (HS-SPEM-GC-TOF-MS) showed that the (Z)-3-hexen-1-ol content increased after each turnover, while the hexanoic acid content showed the opposite trend. The results further showed that both the ADH activity and CsADH gene expression level in oxygen-deficit-turnover tea leaves (ODT) were higher than those of oxygen-turnover tea leaves (OT). The C6-alcohol-derived ester content of OT was significantly higher than that of ODT, while C6-acid-derived ester content showed the opposite trend. Furthermore, the HIP gene family was screened and analyzed, showing that ODT treatment significantly promoted the upregulation of CsHIG4 and CsHIG6 gene expression. These results showed that the formation mechanism of oolong tea aroma quality is mediated by airflow in the lipoxygenase–hydroperoxide lyase (LOX-HPL) pathway, which provided a theoretical reference for future quality control in the postharvest processing of oolong tea.

The Comparison of Total Bile Acid Concentration and Alcohol Dehydrogenase Activity as Markers of Intrahepatic Cholestasis of Pregnancy

Background: Intrahepatic cholestasis of pregnancy (ICP) is the liver disorder in the second or early third trimester of pregnancy. It is characterized by pruritus with increased serum total bile acids concentration (TBA) and increased liver enzymes. It is important to recognize the disease in its early stage. We aimed to investigate the serum alcohol dehydrogenase (ADH) activity and compare it with the concentration of total bile acid (TBA) in women with ICP..Methods: Serum samples were taken from 80 pregnancies with ICP in the second or third trimester of pregnancy and from 80 healthy pregnant women. For measurement of ADH we used the spectrofluorometric and photometric methods. Results: The results shows a statistically significant increase in the activity of ADH I and ADH total (about 60% and 41%, respectively). Activity of ADH I well correlated with aminotransferases (alanine ALT and aspartate AST) and TBA concentration. The total ADH activity was also positively correlated with ALT, AST and TBA. Conclusion: We can state that the activity of class I ADH isoenzyme in the sera of patients with ICP is increased and seems to be a good indicator of liver cell destruction during ICP and is comparable with the value of other markers.

Ethanologenesis and respiration in a pyruvate decarboxylase-deficient Zymomonas mobilis

Objective Zymomonas mobilis is an alpha-proteobacterium with a rapid ethanologenic pathway, involving Entner–Doudoroff (E–D) glycolysis, pyruvate decarboxylase (Pdc) and two alcohol dehydrogenase (ADH) isoenzymes. Pyruvate is the end-product of the E–D pathway and the substrate for Pdc. Construction and study of Pdc-deficient strains is of key importance for Z. mobilis metabolic engineering, because the pyruvate node represents the central branching point, most novel pathways divert from ethanol synthesis. In the present work, we examined the aerobic metabolism of a strain with partly inactivated Pdc. Results Relative to its parent strain the mutant produced more pyruvate. Yet, it also yielded more acetaldehyde, the product of the Pdc reaction and the substrate for ADH, although the bulk ADH activity was similar in both strains, while the Pdc activity in the mutant was reduced by half. Simulations with the kinetic model of Z. mobilis E-D pathway indicated that, for the observed acetaldehyde to ethanol production ratio in the mutant, the ratio between its respiratory NADH oxidase and ADH activities should be significantly higher, than the measured values. Implications of this finding for the directionality of the ADH isoenzyme operation in vivo and interactions between ADH and Pdc are discussed.

Deficiency in alcohol dehydrogenase 2 reduces arsenic in rice grains by suppressing silicate transporters

Paddy fields are anaerobic and facilitate arsenite (As(III)) elution from the soil. Paddy-field rice accumulates arsenic (As) in its grains because silicate transporters actively assimilate As(III) during the reproductive stage. Reducing the As level in rice grains is an important challenge for agriculture. Using a forward genetic approach, we isolated a rice (Oryza sativa) mutant, low arsenic line 3 (las3), whose As levels were decreased in aerial tissues, including grains. The low-As phenotype was not observed in young plants before heading (emergence of the panicle). Genetic analyses revealed that a deficiency in alcohol dehydrogenase (ADH) 2 by mutation is responsible for the phenotype. Among the three rice ADH paralogues, ADH2 was the most efficiently produced in root tissue under anaerobic conditions. In wild-type (WT), silicon and As concentrations in aerial tissues increased with growth. However, the increase was suppressed in las3 during the reproductive stage. Accordingly, the gene expression of two silicate transporters, Lsi1 and Lsi2, was increased in WT around the time of heading, whereas the increase was suppressed in las3. These results indicate that the low-As phenotype in las3 is due to silicate transporter suppression. Measurement of intracellular pH by 31P-nuclear magnetic resonance revealed intracellular acidification of las3 roots under hypoxia, suggesting that silicate transporter suppression in las3 might arise from an intracellular pH decrease, which is known to be facilitated by a deficiency in ADH activity under anaerobic conditions. This study provides valuable insight into reducing As levels in rice grains.

Does Dihydromyricetin Impact on Alcohol Metabolism

Dihydromyricetin (DHM) is a natural flavonoid showing several health promoting effects such as protective activity during severe alcohol intoxication. The mechanism underlying the effects of DHM on alcohol metabolism is virtually unknown. The present paper is focused on clarifying the role of DHM in the liver alcohol elimination at its molecular level. First, impact of DHM on alcohol dehydrogenase (ADH) activity in vitro and the enzyme induction in vivo was examined. Neither the ADH activity nor the enzyme expression were influenced by DHM. Next, the effect of DHM during alcohol intoxication were studied on primary hepatocytes isolated from EtOH-premedicated and untreated rats. The viability of cells exposed to alcohol, estimated based on the released enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST), was slightly affected by DHM. Although the expected hepatoprotective effect of DHM was not fully achieved, DHM (in a concentration manner) proved to reduce the level of ROS/RNS in hepatocytes. However, no change in the rate of alcohol metabolism in vivo was found when rats were administered with a single or repeated dose of ethanol supplemented with DHM. In conclusion, the proposed positive effect of DHM during alcohol intoxication has not been proven. Moreover, there is no effect of DHM on the alcohol metabolism. The “hoped-for” DHM hepatoprotective activity can be attributed to the reduction of ROS/RNS levels in cells.

Expression of an alcohol dehydrogenase gene in a heterotrophic bacterium induces carbon dioxide-dependent high-yield growth under oligotrophic conditions

Sphingobium japonicum strain UT26, whose γ-hexachlorocyclohexane-degrading ability has been studied in detail, is a typical aerobic and heterotrophic bacterium that needs organic carbon sources for its growth, and cannot grow on a minimal salt agar medium prepared without adding any organic carbon sources. Here, we isolated a mutant of UT26 with the ability to grow to visible state on such an oligotrophic medium from a transposon-induced mutant library. This high-yield growth under oligotrophic conditions (HYGO) phenotype was CO2-dependent and accompanied with CO2 incorporation. In the HYGO mutant, a transposon was inserted just upstream of the putative Zn-dependent alcohol dehydrogenase (ADH) gene (adhX) so that the adhX gene was constitutively expressed, probably by the transposon-derived promoter. The adhX-deletion mutant (UT26DAX) harbouring a plasmid carrying the adhX gene under the control of a constitutive promoter exhibited the HYGO phenotype. Moreover, the HYGO mutants spontaneously emerged among the UT26-derived hypermutator strain cells, and adhX was highly expressed in these HYGO mutants, while no HYGO mutant appeared among UT26DAX-derived hypermutator strain cells, indicating the necessity of adhX for the HYGO phenotype. His-tagged AdhX that was expressed in Escherichia coli and purified to homogeneity showed ADH activity towards methanol and other alcohols. Mutagenesis analysis of the adhX gene indicated a correlation between the ADH activity and the HYGO phenotype. These results demonstrated that the constitutive expression of an adhX-encoding protein with ADH activity in UT26 leads to the CO2-dependent HYGO phenotype. Identical or nearly identical adhX orthologues were found in other sphingomonad strains, and most of them were located on plasmids, suggesting that the adhX-mediated HYGO phenotype may be an important adaptation strategy to oligotrophic environments among sphingomonads.

Effect of Pollyallylamine on Alcoholdehydrogenase Structure and Activity

In this article, the effect of polyallylamine (PAA) on the structure and catalytic characteristics of alcohol dehydrogenase (ADH) was studied. For this research, we used methods of stationary kinetics and fluorescence spectroscopy. It has been shown that PAA non-competitively inhibits ADH activity while preserving its quaternary structure. It was established that 0.1 M ammonium sulfate removes the inhibitory effect of PAA on ADH, which is explained by the binding of sulfate anion (NH4)2SO4 with polyallylamine amino groups. As a result, the rigidity of the polymer chain increases and the ability to bind to the active loop of the enzyme increases. It is also shown that sodium chloride removes the inhibitory effect of PAA on ADH due to an electrostatic screening of the enzyme from polyelectrolyte. The method of encapsulating ADH in polyelectrolyte microcapsules was adapted to the structure and properties of the enzyme molecule. It was found that the best for ADH is its encapsulation by adsorption into microcapsules already formed on CaCO3 particles. It was shown that the affinity constant of encapsulated alcohol dehydrogenase to the substrate is 1.7 times lower than that of the native enzyme. When studying the affinity constant of ADH in a complex with PAA to ethanol, the effect of noncompetitive inhibition of the enzyme by polyelectrolyte was observed.

In vitro evaluation of Álcool desidrogenase kinetics in Ziziphus joazeiro fruits to alleviate the harmful effects of alcohol

Ziziphus joazeiro is endemic to the brazilian Caatinga and its fruits can be used as a food supplement by accelerating the ethanol metabolism in the body and reducing the alcohol harmful effects due to high alcohol dehydrogenase (ADH) activity. The objective was to determine the kinetics of ADH activity, in different incubation times, of Z. joazeiro mature fruits as a food supplement. Ziziphus joazeiro fruits, at the fourth maturation stage, were incubated for 0 (no incubation), 3, 6, 12, 24 and 48 hours at room temperature. The ADH activity was determined. ADH activity was higher in fruits incubated for 0 and 3 h. The ADH activity was higher in the early incubation times, probably due to the greater availability of NAD+, which after being reduced to NADH delayed regeneration. Without the cofactor in the oxidized form, the enzymatic activity decreases. Ziziphus joazeiro fruit has the potential to be used as a food supplement accelerating the alcohol metabolism and reducing the harmful effects.

Diagnostics of Fibrosis in Alcoholic Liver Damage

Aim. In this article, the authors determine the severity (index) of histological activity (HAI) and fi brosis in various forms of alcoholic liver disease drawing on the autopsy material, as well as suggest a marker for detecting fi brosis.Materials and methods. The authors studied 110 autopsies and histopathological studies of people who died from ethanol poisoning in the setting of various forms of alcoholic liver damage (95) and traumatic brain injury – control (15). Alcohol dehydrogenase (ADH) activity was studied through histochemical methods; values were estimated through the quantitative morphometry of the histochemical reaction product using the MORFOLOG program developed at the Department for Forensic Medicine (V.A. Porodenko, 1996). Statistical analysis was performed using the STATISTICA 10 software package and a created Exсel database. In order to determine the signifi cance between two compared values, the Student’s t-test was employed. Correlations were estimated using the Spearman’s rank correlation coeffi cient (r).Results. The study revealed various degrees of histological activity and fi brosis in the setting of alcoholic steatosis, hepatitis and cirrhosis. The initial liver damage is characterised by minimal / weak activity and F0–F2 stage of fi brosis. With the progression of the pathological process in the liver, HAI is estimated as moderate and severe (F2–F4 stage of fi brosis). There is a correlation between the development of perisinusoidal and pericellular fi broses (r = –0.655), septae (r = –0.435), connective tissue in the portal tracts and around a vein (r = –0.517) and the number of medium caliber vessels in the liver, as well as between the portal vein diameter and the development of perisinusoidal and pericellular fi broses (r = 0.377). The authors noted high and moderate positive correlation between the ADH activity in zone 3 of the liver acini and the development of necroses and fi brosis, minor cholestases, expansion of the perisinusoidal spaces. The calculated index of fi brosis and ischemic liver damage correlates with its impaired morphofunctional state.Conclusion. The obtained data indicate that fi brosis develops in the early stages of alcoholic liver damage, whose severity can be assessed using the proposed method for determining the index of fi brosis and ischemic liver damage, given that it refl ects both the structural and functional state of the organ.