Gamma-glutamyl Transferase (gamma-glutamyl + transferase)

Distribution by Scientific Domains


Selected Abstracts


Metabolic differences between male and female adolescents with non-alcoholic fatty liver disease, as detected by ultrasound

ACTA PAEDIATRICA, Issue 8 2010
MTB Fernandes
Abstract Background:, Age, developmental stage and gender are risk factors for paediatric non-alcoholic fatty liver disease (NAFLD). Aims:, The aim of this study was to identify differences in clinical or laboratory variables between sexes in adolescents with NAFLD. Methodology:, Ninety obese adolescents including 36 males and 54 females were evaluated. Inclusion criteria for this study were a Body Mass Index above the 95th percentile, as set forth by the National Center for Health Statistics, and an age of 10,19 years. A clinical and laboratory evaluation was conducted for all adolescents. Results:, The variables that were found to be predictive of NAFLD in adolescence were visceral fat, Aminotransferase, Gamma-Glutamyl Transferase, triglyderides, cholesterol and LDL-cholesterol. We also observed that cholesterol and LDL-cholesterol variables were influenced by gender, i.e. there was a significant statistical difference in the values of these variables between male and female adolescents. With regard to cholesterol serum concentrations, the risk was 6.99 times greater for females, compared with 1.2 times for males; and for LDL-cholesterol serum concentrations the risk was 8.15 times greater for females, compared with and 1.26 times for males. Conclusion:, Female adolescents with NAFLD showed a significantly different metabolic behaviour than males. [source]


Effect of green tea and (-)-epigallocatechin gallate on ethanol-induced toxicity in HepG2 cells

PHYTOTHERAPY RESEARCH, Issue 5 2008
Sang Il Lee
Abstract Despite the continuing reports supporting the hepatoprotective effects of green tea against ethanol intoxication, there remain controversies regarding the active compound(s) and molecular mechanism. These issues were addressed in the present study using cultured HepG2 cells exposed to a lethal dose of ethanol. Gamma-glutamyl transferase (GGT) was chosen as a marker of ethanol toxicity because it is widely used in clinics. When the cells were treated with ethanol at various concentrations, there was a dose-dependent increase of GGT activity in the culture media and loss of cell viability. Pretreatment of the cells with green tea extract attenuated the changes significantly. Among the green tea constituents, (-)-epigallocatechin gallate (EGCG) attenuated the ethanol cytotoxicity effectively, whereas l -theanine and caffeine had no effects. The ethanol cytotoxicity was also attenuated by alcohol dehydrogenase inhibitor 4-methyl pyrazol and GGT inhibitor acivicin as well as by thiol modulators such as S -adenosyl- l -methionine, N -acetyl- l -cysteine and glutathione. EGCG failed to prevent the intracellular glutathione loss caused by ethanol, but it appeared to be a strong GGT inhibitor. Therefore the cytoprotective effects of green tea could be attributed to the inhibition of GGT activity by EGCG. This study suggests that GGT inhibitors including EGCG may provide a novel strategy for attenuating ethanol-induced liver damage. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Concurrent validity of the Alcohol Use Disorders Identification Test (AUDIT) and AUDIT zones in defining levels of severity among out-patients with alcohol dependence in the COMBINE study

ADDICTION, Issue 12 2006
Dennis M. Donovan
ABSTRACT Aims To examine among alcohol-dependent out-patient clients the concurrent validity of the Alcohol Use Disorders Identification Test (AUDIT) total score and ,zones' suggested by the World Health Organization for defining levels of severity of alcohol use problems. Design Participants were classified into AUDIT zones (AUDIT total score = 8,15, 16,19, 20,40) and compared on measures of demographics, treatment goals, alcohol consumption, alcohol-related consequences, severity of dependence, physiological dependence, tolerance, withdrawal and biomarkers of alcohol use. Setting Eleven out-patient academic clinical research centers across the United States. Participants Alcohol dependent individuals (n = 1335) entering out-patient treatment in the Combined Pharmacotherapies and Behavioral Interventions (COMBINE) study. Measurements The AUDIT was administered as part of an initial screening. Baseline measures used for concurrent validation included the Structured Clinical Interview for Diagnostic and Statistical Manual, 4th edition (DSM-IV) Disorders, the Alcohol Dependence Scale, the Drinker Inventory of Consequences, the Obsessive-Compulsive Drinking Scale, the University of Rhode Island Change Assessment, the Thoughts about Abstinence Scale, the Form-90, %carbohydrate-deficient transferrin and gamma-glutamyl transferase. Findings Indicators of severity of dependence and alcohol-related problems increased linearly with total score and differed significantly across AUDIT zones. The highest zone, with scores of 20 and above, was markedly different with respect to severity from the other two zones and members of this group endorsed an abstinence goal more strongly. Conclusions The AUDIT total score is a brief measure that appears to provide an index of severity of dependence in a sample of alcohol-dependent individuals seeking out-patient treatment, extending its potential utility beyond its more traditional role as a screening instrument in general populations. [source]


Insulin resistance phenotypes and coronary artery disease in a native Pakistani cohort

INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 5 2008
A. S. Wierzbicki
Summary Objective:, To determine the relationship between insulin resistance (IR) and atheroma burden in Pakistanis. Methods:, A prospective case,control study of 400 patients selected for the presence/absence of angiographic disease. Coronary atheroma burden was quantified and IR and cardiovascular risk factors were measured. Results:, The patients were divided into two groups by QuickI score. Waist circumference (90 ± 10 vs. 90 ± 9 cm; p = 0.7) was similar but the groups differed in body mass index (26.5 ± 3.7 vs. 24.2 ± 3.5 kg/m2; p < 0.001) and waist:hip ratio (0.94 ± 0.09 vs. 0.90 ± 0.06; p < 0.001). Lipid parameters showed similar high-density lipoprotein cholesterol (HDL-C) (0.77 ± 0.23 vs. 0.82 ± 0.22 mmol/l; p = 0.1) differences in triglycerides [1.32 (0.08,3.98) vs. 1.12 (0.37,3.61) mmol/l; p = 0.01], but no difference in low-density lipoprotein cholesterol (LDL-C) (2.75 ± 1.00 vs. 2.90 ± 0.94 mmol/l; p = 0.14). In insulin-resistant patients C-reactive protein (CRP) [6.8 (0.3,175.1) vs. 3.9 (0.2,57.9) mg/l: p < 0.001], sialic acid (82 ± 14 vs. 77 ± 15 mg/l; p < 0.001) aspartate transaminase [24 (7,171) vs. 21 (7,83) IU/l; p < 0.001] and gamma-glutamyl transferase [27 (8,482) vs. 21 (7,168) IU/l; p = 0.005] levels were increased. In insulin-resistant patients (n = 187), coronary artery disease (CAD) burden correlated (r = 0.55) with age (, = 1.62; p < 0.001), HDL-C (, = ,53.2; p < 0.001), lipoprotein (a) (, = 11.4; p = 0.007), smoking (, = 7.98; p = 0.004), CRP (, = 6.06; p = 0.03) and QuickI index (, = ,146; p = 0.04). In contrast in insulin-sensitive patients (n = 178) CAD burden (r = 0.46) correlated with LDL-C (, = 10.0; p = 0.02), CRP (, = 7.13; p = 0.03), HDL-C (, = ,38.1; p = 0.03), and weakly with age (, = 0.73; p = 0.07) and smoking (, = 5.52; p = 0.09). Conclusions:, Indian Asians show a dichotomous insulin-resistance phenotype. Atheroma is associated with low HDL-C and inflammation associated in all but LDL-C is a factor in the insulin sensitive in contrast to age and extent of IR in the insulin resistant. [source]


Ethyl Glucuronide in Hair Compared With Traditional Alcohol Biomarkers,A Pilot Study of Heavy Drinkers Referred to an Alcohol Detoxification Unit

ALCOHOLISM, Issue 5 2009
Gudrun Høiseth
Background:, Traditional biomarkers for heavy alcohol use include serum carbohydrate-deficient transferrin (CDT), the enzymes aspartate aminotranserase (AST), and alanine aminotransferase (ALT) as well as gamma-glutamyl transferase (GGT). Measurement of the nonoxidative ethanol metabolite, ethyl glucuronide (EtG) in hair, has been proposed as a new marker with superior qualities. The aim of this study was to investigate the sensitivity of EtG in hair to detect heavy alcohol use compared with CDT, AST, ALT, and GGT. We also wanted to study the quantitative relation between alcohol intake and the different biomarkers. Methods:, Sixteen patients with a history of heavy alcohol use over the previous 3 months were recruited directly after admission to a withdrawal clinic. They were thoroughly interviewed about their drinking pattern as well as relevant diseases and use of medicines or drugs. Serum was sampled and analyzed for %CDT, AST, ALT, and GGT. Hair samples were collected and analyzed for EtG. Results:, The mean estimated daily intake (EDI) over the previous 3 months was 206 ± 136 g pure alcohol. All patients fulfilled the criteria for heavy alcohol use. The sensitivity to detect heavy alcohol use was 64% for %CDT, 67% for AST, 67% for ALT, 93% for GGT, and 94% for EtG. There was no correlation between the quantitative values of EDI and %CDT, AST, ALT, and GGT. There was a positive, statistically significant correlation between EDI and the level of EtG in hair. Conclusions:, In this study, EtG in hair and GGT showed the best sensitivity to detect heavy alcohol use and there was a positive correlation between EDI and the concentrations of EtG in hair. Before giving recommendations for clinical practice, further studies should be carried out on larger materials and populations with a wider range of alcohol intake. [source]


Treatment of non-alcoholic fatty liver disease with metformin versus lifestyle intervention in insulin-resistant adolescents

PEDIATRIC DIABETES, Issue 1 2009
Kristen J Nadeau
Abstract:, The presence of fatty liver per ultrasound and liver-associated enzymes were measured in a select cohort of youth with both obesity and insulin resistance, and the effect of metformin on these parameters evaluated. Fifty obese, multiethnic, insulin-resistant adolescents (mean age 15.1 yr, mean body mass index 39.8 kg/m2) were randomized to receive lifestyle recommendations plus either twice per day doses of 850 mg of metformin or placebo. Fasting and post-glucose challenge biochemistries and liver ultrasounds were compared at baseline and 6 months. The prevalence of fatty liver was 74%, elevated alanine aminotransferase (ALT) 14%, aspartate aminotransferase (AST) 14%, and gamma-glutamyl transferase (GGT) 17%. Fatty liver was mild in 23%, moderate in 31%, and severe in 46%. Fatty liver was more common in male and Hispanic subjects and elevated ALT more common in Hispanic subjects. Subjects with fatty liver appeared more insulin resistant (higher fasting insulin and triglycerides, lower high-density lipoprotein cholesterol) and had higher ALT and AST. At 6 months, mean ALT, GGT, and fasting insulin improved significantly in all subjects. Fatty liver prevalence (p < 0.04), severity (p < 0.04), and fasting insulin (p < 0.025) improved significantly with metformin compared to placebo. Non-alcoholic fatty liver disease (NAFLD) occurs with a high prevalence and severity in obese, insulin-resistant adolescents. While metformin plus lifestyle intervention appears promising, defining NAFLD therapies capable of preventing fibrosis and cirrhosis requires further study. [source]


Markers of the Hepatic Component of the Metabolic Syndrome as Predictors of Mortality in Renal Transplant Recipients

AMERICAN JOURNAL OF TRANSPLANTATION, Issue 1 2010
D. M. Zelle
Cardiovascular disease (CVD) is a leading cause of mortality in renal transplant recipients (RTRs). Metabolic syndrome (MS) is highly prevalent in RTRs. Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic component of MS. We investigated associations of NAFLD markers with MS and mortality. RTRs were investigated between 2001 and 2003. NAFLD markers, alanine aminotransferase (ALT), gamma-glutamyl transferase (GGT) and alkaline phosphatase (AP) were measured. Bone and nonbone fractions of AP were also determined. Death was recorded until August 2007. Six hundred and two RTRs were studied (age 52 ± 12 years, 55% men). At baseline 388 RTRs had MS. Prevalence of MS was positively associated with liver enzymes. During follow-up for 5.3[4.5,5.7] years, 95 recipients died (49 cardiovascular). In univariate Cox regression analyses, GGT (HR = 1.43[1.21,1.69], p < 0.001) and AP (HR = 1.34[1.11,1.63], p = 0.003) were associated with mortality, whereas ALT was not. Similar associations were found for cardiovascular mortality. Adjustment for potential confounders, including MS, diabetes and traditional risk factors did not materially change these associations. Results for nonbone AP mirrored that for total AP. ALT, GGT and AP are associated with MS. Of these three enzymes, GGT and AP are associated with mortality, independent of MS. These findings suggest that GGT and AP are independently related to mortality in RTRs. [source]


A genome-screen experiment to detect quantitative trait loci affecting resistance to facial eczema disease in sheep

ANIMAL GENETICS, Issue 1 2009
S. H. Phua
Summary Facial eczema (FE) is a secondary photosensitization disease arising from liver cirrhosis caused by the mycotoxin sporidesmin. The disease affects sheep, cattle, deer and goats, and costs the New Zealand sheep industry alone an estimated NZ$63M annually. A long-term sustainable solution to this century-old FE problem is to breed for disease-resistant animals by marker-assisted selection. As a step towards finding a diagnostic DNA test for FE sensitivity, we have conducted a genome-scan experiment to screen for quantitative trait loci (QTL) affecting this trait in Romney sheep. Four F1 sires, obtained from reciprocal matings of FE resistant and susceptible selection-line animals, were used to generate four outcross families. The resulting half-sib progeny were artificially challenged with sporidesmin to phenotype their FE traits measured in terms of their serum levels of liver-specific enzymes, namely gamma-glutamyl transferase and glutamate dehydrogenase. In a primary screen using selective genotyping on extreme progeny of each family, a total of 244 DNA markers uniformly distributed over all 26 ovine autosomes (with an autosomal genome coverage of 79,91%) were tested for linkage to the FE traits. Data were analysed using Haley,Knott regression. The primary screen detected one significant and one suggestive QTL on chromosomes 3 and 8 respectively. Both the significant and suggestive QTL were followed up in a secondary screen where all progeny were genotyped and analysed; the QTL on chromosome 3 was significant in this analysis. [source]


The importance of gamma-glutamyl transferase in lung glutathione homeostasis and antioxidant defense,

BIOFACTORS, Issue 1-4 2003
Jyh-Chang Jean
First page of article [source]


Tyrosine aminotransferase and gamma-glutamyl transferase activity in human fetal hepatocyte primary cultures under proliferative conditions

CELL BIOCHEMISTRY AND FUNCTION, Issue 2 2004
Khaja K. Rehman
Abstract The ontogeny of gamma-glutamyl transferase (GGTase; E.C.2.3.2.2) and tyrosine aminotransferase (TAT; E.C.2.6.1.5) activities in 14 to 36 weeks gestational and neonatal hepatocytes during development of human fetal liver was studied. Subsequently, 20,24 weeks gestational hepatocytes were cultured in media supplemented with epidermal growth factor (EGF) and insulin with or without glucagon and dexamethasone to investigate the proliferation and differentiation of fetal hepatocyte in vitro using GGTase and TAT as biochemical markers. During the development of the liver, the activity of GGTase increased continuously from the first trimester through the third trimester and decreased (p,<,0.001) in neonates. A low basal level of TAT activity was seen only during the third trimester, which then increased significantly (p,<,0.001) in neonates. Fetal hepatocytes, in the presence of EGF and insulin, undergo proliferation from the fourth to 10th day with an increase in cell number (p,<,0.001) and concomitant increase (p,<,0.001) in GGTase activity. As the cells attain confluence, enzyme activity decreased significantly (p,<,0.001) from the 10th to 16th day. Maximal TAT activity (p,<,0.001) was observed at 48,h of culture, which decreased, but not significantly, during cell proliferation and the enzyme activity was regained as the cultures attained confluence. Furthermore, TAT activity was induced synergistically (p<0.001) in the presence of glucagon and dexamethasone, while GGTase was inhibited (p<0.001). These results indicate that GGTase increases with proliferation, whereas TAT, once it has been expressed, is not suppressed during cell proliferation. In conclusion, human fetal hepatocytes undergo enzymic differentiation by 48,h of culture, and proliferate with an increase in GGTase in the presence of growth factors with maintenance of differentiated status up to the studied 16 days of culture. Copyright © 2003 John Wiley & Sons, Ltd. [source]