Associations between γ-glutamyl transferase, metabolic abnormalities and inflammation in healthy subjects from a population-based cohort: A possible implication for oxidative stress

The Association Between Serum Gamma-Glutamyl Transferase and Gastrointestinal Cancer Risk: A Systematic Review and Meta-Analysis

BACKGROUND

Gamma-glutamyl transferase (GGT) has been shown to have associations with several diseases including cancers. Previous studies have investigated the effect of GGT levels on the gastrointestinal (GI) cancer incidence. We aim to systematically investigate these studies to provide better insights into the interrelationship between GGT and GI cancers.

METHODS

Online databases were searched to find relevant studies investigating different GGT levels' effects on the incidence of GI cancers including colorectal, esophageal, liver, pancreas, gastric, and biliary duct cancers. Random-effect meta-analysis was conducted to pool the hazard ratios (HRs) of GGT quartiles (Qs) effect on cancer incidence.

RESULTS

A total of 26 studies were included in the final review, 12 of which underwent meta-analysis that investigated 11 million patients. Based on the meta-analysis, Q4 patients had a 69% higher hazard of GI cancer incidence (HR 1.69, 95% CI 1.41-2.02, p-value < 0.001). The hazard ratio significance was also similar for Q3 (HR 1.22, 95% CI 1.15-1.30, p-value < 0.001) and Q2 (HR 1.10, 95% CI 1.05-1.16, p-value =0.002) of GGT. Colorectal and liver cancers showed a higher hazard ratio among Q2, Q3, and Q4 of GGT compared to Q1. In pancreas and bile duct cancers, only Q4 of GGT had significantly higher HR. Q3 and Q4 of GGT levels had statistically significant associations with gastric cancer incidence.

CONCLUSION

Higher GGT levels correlate with higher rates of GI cancer incidence, especially in colorectal and hepatic cancers. Future studies should investigate this biomarker's potential role in risk assessment for digestive cancers.

Contribution of ferritin and zinc to adverse infant outcomes among pregnancies with prenatal alcohol exposure in South Africa

Nutritional status during pregnancy can impact fetal development, yet less is known about how alcohol may interact with nutritional status to influence infant outcomes. Pregnant women (n=196) completed 2, 24-hour dietary recalls and provided a venous blood sample to be analyzed for liver enzymes (GGT -gamma-glutamyl transferase; ALT -alanine transaminase; and AST -aspartate transferase), iron, ferritin, and zinc concentrations. Infants were assessed at 6 weeks of age. Women who consumed alcohol had significantly higher ferritin levels compared to non-drinkers (51.8 vs. 34.2). While 44% of women had ferritin <30 ug/L (an indicator of iron deficiency), and 24% of women were low in serum iron, and 72% were low in serum zinc. All six drinking measures for 1st trimester and previous week were significantly correlated with GGT and AST levels while 4 out of 6 alcohol measures were associated with levels of ALT and ferritin. At six weeks of age, nearly all physical measures differentiated infants with alcohol exposure from infants without exposure. Controlling for six covariates, maternal ferritin was significantly and inversely associated with infant head circumference (OFC) centile among infants with alcohol exposure. GGT was inversely associated with infant height and weight centile among unexposed infants. Seventy-four percent (74%) of mothers who consumed alcohol were found to be low in serum zinc, yet higher maternal zinc was associated with more dysmorphology. This may indicate that higher zinc status is not protecting the fetus from the teratogenic effects of alcohol. Prenatal alcohol exposure, ferritin, and zinc status influence infant growth and neurodevelopment.

Association of haemato-biochemical indices and blood composite ratios with microfilaridermia in Onchocerciasis patients

BACKGROUND

Onchocerciasis causes chronic systemic inflammation. Several studies have used markers such as haemato-biochemical indices to predict the occurrence of systemic inflammation. This study assessed the variability and predictability of haemato-biochemical indices and blood composite ratios (BCRs) in microfilariae positive (MF+) and microfilariae negative (MF-) subgroups of onchocercomata participants.

METHODS

One hundred and five (105) MF + and 34 MF- participants were retrospectively recruited into the study. Screening for the presence of O. volvulus microfilariae was done from skin snips taken from the left and right iliac crests of participants using established and approved protocols. Haematological and biochemical indices were measured using standard laboratory automated analyzers. Blood composite ratios (BCRs) were calculated as ratios of the absolute parameters involved.

RESULTS

A significantly increased total WBC, absolute eosinophil, eosinophil percent and absolute basophil were observed in the MF + participants compared to MF- participants. Reduced gamma-glutamyl transferase (GGT) with increased estimated glomerular filtration rate (eGFR) was significantly associated with MF + participants compared to MF- participants. BCRs were significantly higher for eosinophil-to-neutrophil ratio (ENR), eosinophil-to-monocyte ratio (EMR), eosinophil-to-basophil ratio (EBR) and eosinophil-to-lymphocyte ratio (ELR) in MF + participants compared to MF- participants. After multivariate adjustment, onchocercomata participants with increased eosinophil counts (aOR = 13.86, 95% CI [2.07-92.90], p = 0.007), ENR x10 (aOR = 1.42, 95% CI [1.05-1.93], p = 0.025), EMR (aOR = 2.64, 95% CI [1.25-5.60], p = 0.011), EBR (aOR = 1.07, 95% CI [1.01-1.10], p = 0.020) and ELR x10 (aOR = 1.69, 95% CI [1.14-2.51], p = 0.009) were more likely to have microfilaridermia.

CONCLUSIONS

Elevated eosinophil counts with higher ENR, EMR, EBR and ELR levels are significantly associated with microfilaridermia in onchocercomata participants. Combining BCRs with eosinophil count significantly led to an improvement in the conventional model for predicting microfilaridermia.

Exploring the Potential Performance of Fibroscan for Predicting and Evaluating Metabolic Syndrome using a Feature Selected Strategy of Machine Learning

Metabolic syndrome (MetS) includes several conditions that can increase an individual's predisposition to high-risk cardiovascular events, morbidity, and mortality. Non-alcoholic fatty liver disease (NAFLD) is a predominant cause of cirrhosis, which is a global indicator of liver transplantation and is considered the hepatic manifestation of MetS. FibroScan® provides an accurate and non-invasive method for assessing liver steatosis and fibrosis in patients with NAFLD, via a controlled attenuation parameter (CAP) and liver stiffness measurement (LSM or E) scores and has been widely used in current clinical practice. Several machine learning (ML) models with a recursive feature elimination (RFE) algorithm were applied to evaluate the importance of the CAP score. Analysis by ANOVA revealed that five symptoms at different CAP and E score levels were significant. All eight ML models had accuracy scores > 0.9, while treebags and random forest had the best kappa values (0.6439 and 0.6533, respectively). The CAP score was the most important variable in the seven ML models. Machine learning models with RFE demonstrated that using the CAP score to identify patients with MetS may be feasible. Thus, a combination of CAP scores and other significant biomarkers could be used for early detection in predicting MetS.

Association of Serum γ-Glutamyltransferase With C-Reactive Protein Levels in Patients With Coronary Heart Disease

Serum γ-glutamyltransferase (GGT) levels have been shown to be associated with C-reactive protein (CRP) levels. Nevertheless, studies on this relationship in coronary heart disease (CHD) populations are limited. This study retrospectively assessed 17 523 patients with CHD undergoing GGT and CRP testing. They were divided into 3 groups according to GGT tertiles. The critical points for high CRP levels was 10.0 mg/L, which corresponded to the 75th percentile. Logistic regression analysis was used to analyze the association between GGT and CRP levels in CHD patients. The baseline analysis showed significant differences in related parameters among patients with CHD. Compared with GGT tertile 1 (T1), the odds ratio (OR) of T3 for GGT in CHD patients was 2.15 (95% confidence interval [CI]: 1.96-2.36). The association between GGT and CRP was higher in males (OR: 2.23; 95% CI: 1.98-2.52) than in females (OR: 2.18; 95% CI: 1.89-2.51). This study showed an association between serum GGT and CRP levels in patients with CHD. GGT may be an inflammatory marker and an additional measure for assessing cardiovascular risk.

Gamma-glutamyl transferase and cardiovascular events in patients with congenital heart disease

INTRODUCTION

Serum gamma-glutamyl transferase activity (GGT) seems to predict cardiovascular events in different populations. However, no data exist on patients with congenital heart disease (CHD).

METHODS

Observational, analytic, prospective cohort study design involving CHD patients and a control population to determine the effect of GGT levels on survival.

RESULTS

A total of 589 CHD patients (58% males, 29 ± 14 years old) and 2745 matched control patients were followed up. A total of 69 (12%) CHD patients had a major acute cardiovascular event (MACE) during the follow-up time (6.1 [0.7-10.4] years). Patients with CHD and a GGT >60 U/L were significantly older, more hypertensive and dyslipidemic, had a worse NYHA functional class and a greater anatomical complexity than CHD patients with a GGT ≤60 U/L. The binary logistic regression analysis showed that age, a great CHD anatomical complexity, and having atrial fibrillation/flutter were the predictive factors of higher GGT levels (>60 U/L). The Kaplan-Meier analysis showed that patients with CHD and a GGT concentration above 60 UL showed the lowest probability of survival compared to that of CHD with GGT ≤60 U/L and controls irrespective of their GGT concentrations (p < .001). Similarly, the multivariable Cox regression analysis found an independent association between higher GGT levels (>60 U/L) and a worse prognosis (HR 2.44 [1.34-4.44], p = .003) among patients with CHD.

CONCLUSION

Patients with CHD showed significant higher GGT levels than patients in the control group having those with higher GGT concentrations (>60 U/L) the worst survival.

Prevalence and associations of metabolic syndrome in patients with alcohol use disorder

Excessive alcohol consumption has been associated with different components of the metabolic syndrome (MetS) such as arterial hypertension, dyslipidemia, type 2 diabetes or obesity. We aimed to analyze the prevalence and associations of MetS in patients with Alcohol Use Disorder (AUD). Cross-sectional study in heavy drinkers admitted for the treatment of AUD between 2013 and 2017. Medical comorbidity, anthropometric data, alcohol use and biological parameters were obtained. MetS was established according to the harmonized definition. A total of 728 patients (22% women) were included; median age was 47 years (IQR: 40–53.5), median alcohol consumption was 160 g/day (IQR: 115–240) and prevalence of MetS was 13.9%. The multivariate analysis showed a significant dose–response effect of estimated glomerular filtration (eGFR) and MetS: relative to patients with eGFR > 90 mL/min, those with eGFR (60–90 mL/min) and those with eGFR < 60 mL/min were 1.93 times (95% CI 1.18–3.15) and 5.61 times (95% CI 1.66–19.0) more likely to have MetS, respectively. MetS was significantly associated with hyperuricemia (OR 2.28, 95% CI 1.36–3.82) and elevated serum GGT (OR 3.67, 95% CI 1.80–7.46). Furthermore, for every increase of 1 year in age, the probability of MetS increased significantly (OR 1.03, 95% CI 1.01–1.05). MetS in heavy drinkers is independently associated with reduced kidney function and metabolic risk factors including hyperuricemia and elevated serum GGT.

Plasma Metabolomics Analysis of Polyvinyl Chloride Workers Identifies Altered Processes and Candidate Biomarkers for Hepatic Hemangiosarcoma and Its Development

BACKGROUND

High-level occupational vinyl chloride (VC) exposures have been associated with hepatic hemangiosarcoma, which typically develops following a long latency period. Although VC is genotoxic, a more comprehensive mode of action has not been determined and diagnostic biomarkers have not been established. The purpose of this study is to address these knowledge gaps through plasma metabolomics.

METHODS

Plasma samples from polyvinyl chloride polymerization workers who developed hemangiosarcoma (cases, n = 15) and VC exposure-matched controls (n = 17) underwent metabolomic analysis. Random forest and bioinformatic analyses were performed.

RESULTS

Cases and controls had similar demographics and routine liver biochemistries. Mass spectroscopy identified 606 known metabolites. Random forest analysis had an 82% predictive accuracy for group classification. 60 metabolites were significantly increased and 44 were decreased vs. controls. Taurocholate, bradykinin and fibrin degradation product 2 were up-regulated by greater than 80-fold. The naturally occurring anti-angiogenic phenol, 4-hydroxybenzyl alcohol, was down-regulated 5-fold. Top affected ontologies involved: (i) metabolism of bile acids, taurine, cholesterol, fatty acids and amino acids; (ii) inflammation and oxidative stress; and (iii) nicotinic cholinergic signaling.

CONCLUSIONS

The plasma metabolome was differentially regulated in polyvinyl chloride workers who developed hepatic hemangiosarcoma. Ontologies potentially involved in hemangiosarcoma pathogenesis and candidate biomarkers were identified.

Evaluation of oxidative/nitrative stress and uterine artery pulsatility index in early pregnancy

Introduction

Increased oxidative/nitrative stress is characteristic not only in pathologic, but also in healthy pregnancy. High uterine artery pulsatility index (UtAPI) at the end of the first trimester is associated with altered placentation and elevated risk for adverse pregnancy outcomes. We aimed to examine the relationship of systemic oxidative/nitrative stress and uterine artery pulsatility index in the first trimester and their correlation to pregnancy outcomes.

Material and methods

Healthy pregnant women were recruited at 12-13th gestational week ultrasound examination; UtAPI was determined by color Doppler ultrasound. Patients were divided into high (UtAPI ≥ 2.3) (n = 30) and low (n = 31) resistance groups, and pregnancies were followed until labor. Systemic oxidative/nitrative stress was estimated by measuring total peroxide level, total antioxidant capacity and nitrotyrosine level.

Results

Plasma total peroxide level was significantly lower (2,510 ± 39 µM vs. 2,285 ± 59 µM), total antioxidant capacity was higher (781 ± 16 mM CRE vs. 822 ± 13 mM CRE) in the high UtAPI group, which were accompanied by lower birth weight (3,317 ± 64 vs. 3,517 ± 77 g, P < 0.05). Plasma total peroxide level showed a negative correlation (by Pearson) to UtAPI (P < 0.01) and positive correlation to birth weight (P < 0.05).

Conclusions

According to our results, lower systemic oxidative stress showed correlation with high UtAPI measured between the 12-13th weeks of gestation. We also found significant differences in the birth weight of healthy newborns; therefore it is worth examining this relationship in pathological pregnancies.

Serum Gamma Glutamyltransferase Is Associated with 25-Hydroxyvitamin D Status in Elderly Patients with Stable Coronary Artery Disease

Background: No previous study has investigated the association between gamma glutamyltransferase (GGT) and vitamin D in patients with stable coronary artery disease (CAD). We investigated the cross-sectional associations between vitamin D status as assessed by serum 25(OH)D and GGT. Methods: 169 patients were enrolled. Study population was divided into three groups: 1: 25(OH)D < 10 ng/mL (n = 59); 2: 25(OH)D 10–20 ng/mL (n = 82), and 3: 25(OH)D > 20 ng/mL (n = 28). Based on a cut-off GGT value identified in ROC analysis, we also divided the study population to compare the following groups: GGT ≤19 (n = 66) and GGT >19 (n = 103). Results: GGT activity was the highest in vitamin D severely deficient patients and the lowest in vitamin D insufficient patients. GGT was inversely correlated with 25(OH)D concentrations (R = −0.23; p = 0.002). The receiver operating characteristics curve identified the discrimination threshold of GGT of >19 U/L in predicting vitamin D deficiency. Higher leukocyte and neutrophil counts and lower 25(OH)D concentration were found in patients with GGT > 19 U/L. Conclusions: We identified an interaction between declining 25(OH)D levels and rising GGT levels with increasing age, which resulted in an unfavorable 25(OH)D-to-GGT ratio in stable CAD patients. These results suggest that these changes might further contribute to a high cardiovascular risk in the elderly.

Evaluation of the modulatory effects of Piper guineense leaves and seeds on egg albumin-induced inflammation in experimental rat models

ETHNOPHARMACOLOGICAL RELEVANCE

Inflammation processes are implicated in many degenerative diseases. Piper guineense, a West African spice belonging to the Piperaceae family has been reported to contain anti-inflammatory agents.

AIM OF STUDY

This study determined the modulatory effects of methanolic extracts of Piper guineense leaves and seeds on egg albumin-induced inflammation in rats.

STUDY DESIGN AND METHODS

Inflammation in the hind paw was induced by injecting 0.1ml egg albumin subcutaneously. Treatments including diclofenac were given orally. Rectal temperature and paw size were monitored hourly for the first 3 h' post-induction of inflammation and then at the 6th and 24th hour. Serum levels of CRP, MDA, LDH and GGT activities were determined at these hours.

RESULTS

Results showed that egg albumin-induced inflammation caused a significant (p < 0.05) increase in paw size and rectal temperature. It further showed that treatment with the leaves and seed extracts reversed the effect of inflammation on serum levels of CRP and MDA, and on LDH and GGT activities similar to diclofenac in rats.

CONCLUSION

Extracts of the Piper guineense seed and leaves have potentials of being used as an anti-inflammatory agent but further studies need to be done to determine their toxicity and effects on immunological markers of inflammation.

A 12-week, randomized, double-blind study to evaluate the efficacy and safety of liver function after using fermented ginseng powder (GBCK25)

Background

Recently, clinical research has suggested that red ginseng components play a role in liver protection and combating fatigue. However, fermented ginseng has not been analyzed for liver-protective or anti-fatigue effects.

Objective

This study evaluates the positive effects of fermented ginseng powder (GBCK25) on liver function.

Methods

Ninety participants with elevated alanine aminotransferase levels (35 ≤ ALT ≤1 05 IU/L) were randomized to one of three groups. The participants were treated with GBCK25 tablets at a dose of 500 mg/day (high dose), 125 mg/day (low dose), or placebo group daily for 12 weeks. The primary outcomes included changes in ALT and gamma-glutamyl transferase (GGT) levels. The secondary outcomes included changes in aspartate amino-transferase (AST), high-sensitivity C-reactive protein (hs-CRP), multidimensional fatigue scale, lipid profile, and antioxidant markers.

Results

In male subjects, after 12 weeks of low-dose GBCK25 (125 mg) supplementation, the GGT (P = 0.036) and hs-CRP (P = 0.021) levels decreased significantly more than those in the placebo group. High-dose GBCK25 (500 mg) supplementation significantly decreased the fatigue score compared with the placebo group. There were no clinically significant differences between the groups when studying any safety parameter.

Conclusion

Our results suggest that GBCK25 supplementation has beneficial effects on liver function.

Trial registration

This study was registered at Clinical Trials.gov (NCT03260543).

The association between C-reactive protein and common blood tests in apparently healthy individuals undergoing a routine health examination

BACKGROUND

C-reactive protein (CRP) is considered a marker of inflammation. We sought to evaluate the association between CRP level and commonly use blood tests in apparently healthy population.

METHODS

A cross-sectional study of all visits in a routine health examination center between 1/2002 and 7/2018. CRP, complete blood count and chemistry blood panel were evaluated in each visit. Visits of individuals who had CRP above the 99th percentile or use statins were excluded. Correlation between CRP and blood tests was evaluated in the whole cohort as well as in sub-populations.

RESULTS

Blood parameters of 33,261 visits were included. Moderate positive correlation between CRP and white blood cells count (r = 0.269), neutrophils count (r = 0.275), triglycerides (r = 0.275), alkaline phosphatase (r = 0.221) and gamma glutamyl transpeptidase (r = 0.220) was evaluated. Correlation with triglycerides was stronger in female then in males (r = 0.38 vs. 0.25). Uric acid was positively correlated in females and males. In participants under 30 years, inverse correlation with hemoglobin, creatinine and albumin levels and positive correlation with cholesterol were documented.

CONCLUSION

Significant moderate association between CRP and several blood tests was evaluated in apparently healthy population. This information should be used for further studies of the relationship between inflammation and biological processes.

Association between Serum Gamma-Glutamyltransferase and Prevalence of Metabolic Syndrome Using Data from the Korean Genome and Epidemiology Study

BACKGROUND

The aim of this study was to determine whether there is a positive correlation between gamma-glutamyltransferase (GGT) levels and the prevalence of metabolic syndrome and whether GGT can be used as an easily checkable metabolic index using data from the large-scale Korean Genome and Epidemiology Study (KoGES).

METHODS

We obtained data of 211,725 participants of the KoGES. The collected data included age, sex, height, weight, waist circumference, and various biochemical characteristics, including serum GGT levels. The data of study participants who ingested more than 40 g/day of alcohol and who were diagnosed with metabolic syndrome at baseline was excluded. We analyzed the prevalence of metabolic syndrome according to GGT quartiles in both genders.

RESULTS

The GGT level was significantly higher in subjects with metabolic syndrome compared to normal subjects (37.92±48.20 mg/dL vs. 25.62±33.56 mg/dL). The prevalence of metabolic syndrome showed a stepwise increase with GGT quartiles in both male and female subjects. Compared to the lowest GGT quartile, the odds ratio was 1.534 (95% confidence interval [CI], 1.432 to 1.643), 1.939 (95% CI, 1.811 to 2.076), and 2.754 (95% CI, 2.572 to 2.948) in men and 1.155 (95% CI, 1.094 to 1.218), 1.528 (95% CI, 1.451 to 1.609), and 2.022 (95% CI, 1.921 to 2.218) in women with increasing GGT quartile. The cutoff value of GGT predicting risk of metabolic syndrome was 27 IU/L in men and 17 IU/L in women.

CONCLUSION

We suggested that GGT could be an easily checkable marker for the prediction of metabolic syndrome.

The Association Between Metabolic Syndrome and Serum Concentrations of Micronutrients, Inflammation, and Oxidative Stress Outside of the Clinical Reference Ranges: A Cross-Sectional Study

BACKGROUND

Clinical reference ranges are often used to assess nutritional status, but whether having lower or higher than the current clinical reference range for micronutrients, inflammation, and oxidative stress is related to metabolic syndrome (MetS) is not known. Our objectives are to estimate the odds of having MetS outside of established clinical references, and to identify any effect modifications by sex have for these relationships.

METHODS

Data from the 2005 to 2006 National Health and Nutrition Examination Survey were used (≥20 years; N = 2049) with MetS defined utilizing the harmonized criteria from the Joint Interim Statement. The odds of having MetS in individuals with lower or higher than the clinical reference range for the serum concentrations of micronutrient antioxidants, inflammation, and oxidative stress were estimated following adjustments for age, sex, ethnicity, education, income, smoking, alcohol intake, recreational physical activity, and BMI.

RESULTS

Having lower than the clinical reference range for carotenoids and vitamin C [odds ratios (95% confidence interval): 1.37 (1.05-1.78) and 1.39 (1.01-1.90), respectively] was associated with significantly greater odds of MetS. By contrast, having higher than the clinical reference range for vitamins A and E, uric acid, and γ-glutamyl transferase (GGT) [2.10 (1.50-2.92), 2.36 (1.78-3.13), 2.65 (1.54-4.57), and 2.08 (1.61-2.69), respectively] was associated with higher odds of MetS, whereas higher levels of vitamins B12 were protective [0.64 (0.42-0.98]. Sex moderated these relationships for carotenoids, vitamin A, C, E, uric acid, C-reactive protein, and GGT.

CONCLUSIONS

Lower carotenoids and vitamin C and higher vitamins A and E, uric acid, and oxidative stress were associated with a greater likelihood of MetS, whereas higher vitamin B12 was protective. Further research is necessary to replicate these findings in a prospective setting to confirm the importance of the overall and sex-specific findings.

The Effect of Roux-en-Y vs. Omega-Loop Gastric Bypass on Liver, Metabolic Parameters, and Weight Loss

BACKGROUND

Omega-loop gastric bypass (OLGB) results in weight loss (WL) but data on its impact on liver and glucose metabolism compared to Roux-en-Y gastric bypass (RYGB) is lacking. Therefore, the aim of this study was to compare the development of hepatic and metabolic markers as well as WL between the above-mentioned surgical groups during the first postoperative year.

METHODS

We retrospectively evaluated the respective parameters in non-diabetic morbidly obese patients who underwent either RYGB (n = 25) or OLGB (n = 25).

RESULTS

Compared to RYGB, OLGB showed a greater WL percentage. Liver transaminases dropped in RYGB, while rose in OLGB. No correlation between aspartate transaminase, alanine transaminase, and WL could be detected. Gamma-glutamyltransferase decreased significantly in RYGB over the first 3 months, while it increased in OLGB. We found higher levels of triglycerides, insulin, homeostasis model assessment of insulin resistance (HOMA2-IR), and liver fat percentage in RYGB at baseline, despite matching the groups for age, sex, and BMI. Those differences disappeared, except for triglycerides, within 1 year. All metabolic parameters correlated with WL.

CONCLUSION

OLGB results in greater WL but transiently deteriorated several liver parameters in the first postoperative year. This was not associated with WL. The impact of these results on hepatic outcomes such as non-alcoholic steatohepatitis and fibrosis progression requires further studies. In both groups, improved insulin resistance and sensitivity were correlated with higher WL and lower liver fat percentage, respectively.

Serum Gamma-glutamyl Transferase Concentration Within the Reference Range is Related to the Coronary Heart Disease Risk Prediction in Korean Men: Analysis of the Korea National Health and Nutrition Examination Survey (V-1, 2010 and V-2, 2011)

BACKGROUND

Limited data exist on the association of serum gamma-glutamyl transferase (GGT) level within the reference range with the increased risk of coronary heart disease (CHD) prediction in men. The study examined the association between serum GGT concentration within the reference range and the CHD risk prediction in Korean men.

METHODS

The study employed data from Korean National Health and Nutrition Examination Survey (V-1, 2010 and V-2, 2011) where a total of 1301 individuals were analyzed. A 10-year CHD risk prediction was computed using the Framingham Risk Score (FRS) modified by the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III).

RESULTS

Positive correlations were established between log-transformed GGT concentration and FRS (r = 0.237, P < 0.001). After adjustment of body mass index, the amount of alcohol intake and low-density lipoprotein-cholesterol, the odds ratio (95% confidence interval) for intermediate risk and beyond of 10-year CHD prediction (10-year risk ≥10%) with lowest quartile of participants was 1.21 (0.78-1.87) for second quartiles, 1.39 (0.88-2.21) for third quartiles and 2.03 (1.23-3.34) for highest quartiles.

CONCLUSIONS

Higher serum GGT within its reference range was significantly correlated with a 10-year CHD risk prediction estimation using NCEP ATP III in Korean men.

Urinary polycyclic aromatic hydrocarbons and measures of oxidative stress, inflammation and renal function in adolescents: NHANES 2003-2008

OBJECTIVE

Recent evidence has suggested that polycyclic aromatic hydrocarbons (PAHs) may contribute to cardiometabolic and kidney dysfunction by increasing oxidative stress, but little is known about impacts in childhood.

STUDY DESIGN

We performed cross-sectional analyses of 660 adolescents aged 12-19 years in the 2003-2008 National Health and Nutrition Examination Survey (NHANES), using levels of 10 monohydroxylated urinary PAH metabolites as our exposure. Our primary outcomes of interest were biomarkers of oxidative stress and renal function, including estimated glomerular filtration rate (eGFR), urinary albumin to creatinine ratio (ACR), insulin resistance, and serum uric acid, gamma glutamyl transferase (GGT) and C-reactive protein (CRP).

RESULTS

We observed statistically significant associations between PAH metabolites and levels of serum GGT, CRP, uric acid and eGFR. Each 100% increase in 2-hydroxyphenanthrene was related to a 3.36% increase in uric acid (95% CI: 0.338-6.372; p=0.032), a 3.86% increase in GGT (95% CI: 1.361-6.362; p=0.005) and a 16.78% increase in CRP (95% CI: 1.848-31.689; p=0.029). Each 100% increase in 4-hydroxyphenanthrene was associated with a 6.18% increase in GGT (95% CI: 4.064-8.301; p<0.001) and a 13.66% increase in CRP (95% CI: 2.764-24.564; p=0.017). Each 100% increase in 9-hydroxyfluorene was associated with a 2.58% increase in GGT (95% CI: 0.389-4776; p=0.024). Each 100% increase in 3-hydroxyphenanthrene was associated with a 2.66% decrease in eGFR (95% CI: -4.979 to -0.331; p=0.028).

CONCLUSIONS

Urinary PAH metabolites were associated with serum uric acid, GGT and CRP, suggesting possible impacts on cardiometabolic and kidney function in adolescents. Prospective work is needed to investigate the potential long-term health consequences of these findings.

Contribution of Inflammation, Oxidative Stress, and Antioxidants to the Relationship between Sleep Duration and Cardiometabolic Health

OBJECTIVES

To explore the interrelationship and mediating effect of factors that are beneficial (i.e., antioxidants) and harmful (i.e., inflammation and oxidative stress) to the relationship between sleep and cardiometabolic health.

DESIGN

Cross-sectional data from the 2005-2006 National Health and Nutrition Examination Survey.

SETTING

Nationally representative population sample from the US.

PARTICIPANTS

Age ≥ 20 y with sleep data; final analytical sample of n = 2,079.

INTERVENTIONS

N/A.

MEASUREMENTS AND RESULTS

Metabolic syndrome was classified according to the Joint Interim Statement, and sleep duration was categorized as very short, short, adequate, and long sleepers (≤ 4, 5-6, 7-8, and ≥ 9 h per night, respectively). The indirect mediation effect was quantified as large (≥ 0.25), moderate (≥ 0.09), modest (≥ 0.01), and weak (< 0.01). In general, inflammation was above the current clinical reference range across all sleep duration categories, whereas oxidative stress was elevated among short and very short sleepers. Select sleep duration- cardiometabolic health relationships were mediated by C-reactive protein (CRP), γ-glutamyl transferase (GGT), carotenoids, uric acid, and vitamins C and D, and were moderated by sex. Specifically, moderate-to-large indirect mediation by GGT, carotenoids, uric acid, and vitamin D were found for sleep duration-waist circumference and -systolic blood pressure relationships, whereas vitamin C was a moderate mediator of the sleep duration-diastolic blood pressure relationship.

CONCLUSIONS

Several factors related to inflammation, oxidative stress, and antioxidant status were found to lie on the casual pathway of the sleep duration-cardiometabolic health relationship. Further longitudinal studies are needed to confirm our results.

Serum Gamma-Glutamyltransferase Levels are Associated With Concomitant Cardiovascular Risk Factors in Korean Hypertensive Patients: A Nationwide Population-Based Study

Previous studies suggested that serum gamma-glutamyltransferase (GGT) levels were associated with the prevalence of cardiovascular disease (CVD) risk factors including hypertension, diabetes mellitus (DM), and metabolic syndrome (MetS) in the general population. We aimed to investigate the relationship between serum GGT levels and CVD risk factors in Korean hypertensive patients. This cross-sectional study was based on data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2011 to 2012. The analysis included 1541 hypertensive participants. Study participants were divided into groups according to tertiles of serum GGT with cutoff points of 20 and 35 U/L. Serum GGT levels were positively associated with the components of MetS (P value < 0.05, except for systolic blood pressure and high-density lipoprotein cholesterol). After adjusting for possible confounders, serum GGT levels were associated with an increased risk of MetS, high waist circumference, high triglyceride level, fasting plasma glucose, DM, and the urinary albumin-to-creatinine ratio (P = 0.001). In hypertensive patients, serum GGT levels are positively associated with major cardiovascular risk factors such as MetS, DM, and urinary albumin excretion.

A single blueberry (Vaccinium corymbosum) portion does not affect markers of antioxidant defence and oxidative stress in healthy volunteers following cigarette smoking

We previously reported that a portion of blueberries reversed endothelial dysfunction induced by acute cigarette smoking. Since smoking-induced endothelial dysfunction is associated with a condition of oxidative stress, we evaluated whether the observed effect was mediated by modulation of markers of oxidative stress and antioxidant defence. Fourteen out of 16 male healthy smokers previously enrolled, participated in a three-armed randomized controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300g of blueberries) + smoking (one cigarette); control treatment (300ml of water with sugar) + smoking (one cigarette). The cigarette was smoked 100min after blueberry/control/water consumption. Each treatment was separated by 1 week of washout period. Plasma vitamin (C, B12 and folate) and aminothiol concentrations, endogenous [formamidopyrimidine-DNA glycosylase (FPG)-sensitive sites] and oxidatively induced DNA damage (resistance to H2O2-induced DNA damage) in peripheral blood mononuclear cells (PBMCs) were measured at baseline and 20, 60, 90, 120min and 24h after smoking. On the whole, analysis of variance did not show a significant effect of treatment on the modulation of markers of oxidative stress and antioxidant defence but revealed an effect of time for plasma concentrations of vitamin C (P = 0.003), B12 (P < 0.001), folate (P < 0.001), total cysteine (P = 0.007) and cysteine-glycine (P = 0.010) that increased following the three treatments after smoking. No significant effect of treatment was observed for the levels of FPG-sensitive sites (P > 0.05) and H2O2-induced DNA damage (P > 0.05) in PBMCs. In conclusion, the consumption of a single blueberry portion failed to modulate markers of oxidative stress and antioxidant defence investigated in our experimental conditions. Further studies are necessary to elucidate this finding and help clarifying the mechanisms of protection of blueberries against smoking-induced endothelial dysfunction.

Adjuvant sorafenib therapy in patients with resected hepatocellular carcinoma: evaluation of predictive factors

Currently there is no predictor for survival after adjuvant sorafenib in patients with hepatocellular carcinoma (HCC) who have undergone curative resection. Thirty-eight patients who underwent curative resection of HCC received adjuvant sorafenib therapy between August 2009 and March 2012. Clinicopathological parameters including patient factors, tumor factors, liver background, and inflammatory factors (before surgery and dynamic changes after sorafenib therapy) were evaluated to identify predictors for overall survival (OS) and recurrence-free survival (RFS). The recurrence rate, mortality rate, and clinicopathological data were also compared. Increased NLR after sorafenib (HR = 3.199, 95 % CI 1.365-7.545, P = 0.008), increased GGT after sorafenib (HR = 3.204, 95 % CI 1.333-7.700, P = 0.009), and the presence of portal vein thrombosis (HR = 2.381, 95 % CI 1.064-5.328, P = 0.035) were risk factors related to RFS. By contrast, increased NLR after sorafenib was the only independent risk factor related to OS (HR = 4.647, 95 % CI 1.266-17.053, P = 0.021). Patients with increased NLR or increased GGT after sorafenib had a higher incidence of recurrence and death. Patients who had increased NLR tended to have higher preoperative levels of NLR and GGT. There were no differences in clinicopathological factors in patients with increased GGT and decreased GGT. In conclusion, increased NLR predicted a worse OS and RFS in patients with HCC who underwent curative resection with adjuvant sorafenib therapy. Increased GGT predicted a worse OS. NLR and GGT can be monitored dynamically before and after sorafenib therapy.

sRAGE, inflammation, and risk of atrial fibrillation: results from the Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVE

Advanced glycation end products (AGEs) may cause inflammation by binding to their cellular receptors (RAGE). Soluble RAGE (sRAGE) acts as a decoy receptor for AGEs and may prevent inflammation. Chronic low-grade inflammation is a risk factor for cardiovascular disease, including atrial fibrillation (AF).

METHODS

We studied 1,068 participants in a subsample of the Atherosclerosis Risk in Communities (ARIC) Study who had baseline measurements of sRAGE (mean age 56, 60% female, 21% Black). Inflammation was assessed using measurements of high sensitivity C-reactive protein (hsCRP), fibrinogen, gamma-glutamyl transferase (GGT) and white blood cell (WBC) count. AF events were identified using ECG data, hospitalization discharge codes, and linkage to the National Death Index.

RESULTS

Compared to the highest quartile (>1272.4 pg/mL), the lowest quartile of sRAGE (<714 pg/mL) was associated with higher baseline levels of inflammation (hsCRP ≥3 mg/L: OR=2.21 [95% CI 1.41-3.49], fibrinogen ≥400 mg/dL: OR=4.31 [95% CI 1.50-12.41], GGT ≥36 U/L in women and ≥61 U/L in men: OR=5.22 [95% CI 2.66-10.22], WBC >6.2×10⁹/L: OR=2.38 [95% CI 1.52-3.72]). sRAGE was not prospectively associated with 6-year change in inflammatory markers (hsCRP or GGT). There was no significant association of sRAGE and risk of AF (HR 1.49 [95% CI: 0.80-2.78] for the 1st vs. 4th quartile of sRAGE).

CONCLUSIONS

sRAGE was strongly inversely associated with markers of inflammation at baseline, but not prospectively. sRAGE was not significantly associated with incident AF. This supports a role for sRAGE in attenuating current inflammation, but it remains unclear whether sRAGE plays a role in the development of AF.

Relationship between serum γ-glutamyltransferase level and leukocyte count in Korean children and adolescents

BACKGROUND

Elevated γ-glutamyltransferase (GGT) is an important risk factor for cardiometabolic diseases, which may result from chronic low-grade inflammation. Leukocyte count is widely considered a marker of inflammation and is also an independent predictor of cardiometabolic diseases. This study aimed to determine the relationship between GGT and leukocyte count in a representative sample of Korean children and adolescents.

METHODS

A nationwide cross-sectional study was conducted to examine the relationship between GGT and leukocyte count in 830 boys and 714 girls (aged 10-18 years), using data from the 2010-2012 Korean National Health and Nutrition Examination Survey. The odds ratios (ORs) and 95% confidence intervals (CIs) for high leukocyte count (≥ 75th percentile) were calculated across GGT quartiles using multiple logistic regression analyses.

RESULTS

Leukocyte count gradually increased in accordance with serum GGT quartiles in both boys and girls (all p-values < 0.001). The OR (95% CI) for high leukocyte of the highest GGT quartile was 2.19 (1.05-4.58) for boys and 2.36 (1.13-4.93) for girls after adjusting for age, BMI, blood pressure, total cholesterol, triglyceride, physical activity, household income, and residential area. Similarly, these positive associations were observed in multiple logistic regression analysis using log2-transformed serum GGT as a continuous variable.

CONCLUSIONS

The present study demonstrates a positive relationship between serum GGT and leukocyte count. These findings indicate that serum GGT may be closely related with subclinical low-grade inflammation in children and adolescents.

Changes of liver enzymes and bilirubin during ischemic stroke: mechanisms and possible significance

Background

Small changes of bilirubin and liver enzymes are often detected during the acute phase of stroke, but their origin and significance are still poorly understood.

Methods

On days 0, 3, 7, and 14 after admission, 180 patients with ischemic stroke underwent serial determinations of bilirubin, GOT, GPT, γGT, alkaline phosphatase, C-reactive protein (CRP) and complete blood count. On days 0 and 7 common bile duct diameter was measured by ultrasound, and on day 3 cerebral infarct volume (IV) was calculated from CT scan slices.

Results

During the first week GOT, GPT, γGT (P < 0.001) and CRP (P = 0.03) increased with subsequent plateau, while significant decrements (P < 0.001) concerned unconjugated bilirubin, erythrocytes and haemoglobin. Alkaline phosphatase, direct bilirubin and common bile duct diameter remained stable. IV correlated with CRP, leukocytes, GOT, γGT (r > 0.3, P < 0.001 for all) and direct bilirubin (r = 0.23, P = 0.008). In multivariate analysis only CRP and GOT remained independently associated with IV (P < =0.001). The correlation of IV with GOT increased progressively from admission to day 14. GOT independently correlated with GPT which, in turn, correlated with γGT. γGT was also highly correlated with leukocytes. Unconjugated bilirubin correlated with haemoglobin, which was inversely correlated with CRP.

Conclusions

The changes of bilirubin and liver enzymes during ischemic stroke reflect two phenomena, which are both related to IV: 1) inflammation, with consequent increment of CRP, leukocytes and γGT, and decrease of haemoglobin and unconjugated bilirubin and 2) an unknown signal, independent from inflammation, leading to increasing GOT and GPT levels.

Clinical association between serum γ-glutamyltransferase levels and the development of insulin resistance in Korean men: a 5-year follow-up study

AIMS

In recent years, γ-glutamyltransferase has emerged as a predictor of cardiovascular disease, Type 2 diabetes mellitus, the metabolic syndrome and hypertension. However, it is not yet certain whether γ-glutamyltransferase is a predictor for insulin resistance. The aim of this study was to examine the longitudinal association between baseline γ-glutamyltransferase level and the development of insulin resistance in Korean men.

METHODS

We performed a prospective cohort study, involving 22 931 healthy Korean men without baseline insulin resistance (homeostasis model assessment of insulin resistance, HOMA-IR < 2.7) for 5 years. We checked the HOMA-IR serially to monitor the development of insulin resistance (incidence of HOMA-IR ≥ 2.7). A Cox proportional hazards model was used to determine hazard ratios for insulin resistance by quartile groups of baseline serum γ-glutamyltransferase levels.

RESULTS

During 81 208.6 person-years of follow-up, 3856 (16.8%) cases of insulin resistance developed between 2006 and 2010. After adjusting for multiple covariates, including baseline HOMA-IR, the hazard ratios (95% CI) for incident insulin resistance comparing the second to the fourth quartile of baseline serum γ-glutamyltransferase levels with the first quartile were 1.19 (1.06-1.33), 1.38 (1.23-1.53) and 1.58 (1.41-1.77), respectively (P for trend < 0.001).

CONCLUSIONS

Our findings show that serum γ-glutamyltransferase level could be a predictor of the development of insulin resistance in Korean men.

Relationships of different blood pressure categories to indices of inflammation and platelet activity in sustained hypertensive patients with uncontrolled office blood pressure

Failure to decrease blood pressure (BP) normally during nighttime (non-dipping) in hypertension is associated with higher cardiovascular morbidity and mortality. In addition, non-dipping BP is associated with increased platelet activity and inflammatory response; however, there has been no study to evaluate the relationship of non-dipping BP to indices of platelet activity and inflammation in uncontrolled hypertensive patients. In the present study, hypertensive subjects with uncontrolled office BP were firstly divided into three groups: 84 subjects with white coat effect and 365 subjects with true uncontrolled hypertension. Then, true uncontrolled hypertensive patients were divided into two groups: 158 patients with dipping and 207 patients with non-dipping. Mean platelet volume (MPV), uric acid (UA), γ-glutamyltransferase (GGT), C-reactive protein (CRP), and high-sensitivity CRP (hs-CRP) levels were studied. The general characteristics and risk factors for coronary artery disease (CAD) of the study population were similar among the groups. MPV, UA, GGT, CRP, and hs-CRP levels were significantly higher in non-dipper group than both dipper and white coat effect groups, and were significantly higher in dipper group than in white coat effect group (MPV: 9.1 ± 1.3, 8.7 ± 1.1, and 8. ± 0.9 fL; UA: 6.9 ± 1.2, 5.9 ± 1.4, and 4.1 ± 0.8 mg/dL; GGT: 38.9 ± 11.1, 33.6 ± 14.9, and 25.2 ± 9.2 U/L; CRP: 7.1 ± 2.4, 6.2 ± 1.9, and 3.9 ± 0.8 mg/dL; hs-CRP: 3.8 ± 1.5, 3.3 ± 1.2, and 2.0 ± 0.6, non-dipper, dipper, and white coat effect groups, respectively, all p values <0.01). All study parameters strongly correlated with each other. In conclusion, in hypertensive patients with uncontrolled office BP, presence of non-dipping BP is associated with increased platelet activity and inflammation, which can be one of the underlying plausible mechanisms of non-dipping BP status.

Substitution of TAG oil with diacylglycerol oil in food items improves the predicted 10 years cardiovascular risk score in healthy, overweight subjects

Dietary fat is normally in TAG form, but diacylglycerol (DAG) is a natural component of edible oils. Studies have shown that consumption of DAG results in metabolic characteristics that are distinct from those of TAG, which may be beneficial in preventing and managing obesity. The objective of the present study was to investigate if food items in which part of the TAG oil is replaced with DAG oil combined with high α-linolenic acid (ALA) content would influence metabolic markers. A 12-week double-blinded randomised controlled parallel-design study was conducted. The participants (n 23) were healthy, overweight men and women, aged 37–67 years, BMI 27–35 kg/m², with waist circumference >94 cm (men) and >88 cm (women). The two groups received 20 g margarine, 11 g mayonnaise and 12 g oil per d, containing either high ALA and sn-1,3-DAG or high ALA and TAG. Substitution of TAG oil with DAG oil in food items for 12 weeks led to an improvement of the predicted 10 years cardiovascular risk score in overweight subjects by non-significantly improving markers of health such as total body fat percentage, trunk fat mass, alanine aminotransferase, systolic blood pressure, γ-glutamyl transferase, alkaline phosphatase and total fat-free mass. This may suggest that replacing TAG oil with DAG oil in healthy, overweight individuals may have beneficial metabolic effects.

A new metabolomic assay to examine inflammation and redox pathways following LPS challenge

BACKGROUND

Shifts in intracellular arginine (Arg) and sulfur amino acid (SAA) redox metabolism modulate macrophage activation, polarization and phenotype. Despite their importance in inflammation and redox regulatory pathways, comprehensive analysis of these metabolic networks was not previously possible with existing analytical methods.

METHODS

The Arg/thiol redox LC-MS/MS metabolomics assay permits simultaneous assessment of amino acids and derivative products generated from Arg and SAA metabolism. Using this assay, LPS-induced changes in macrophage amino acid metabolism were monitored to identify pathway shifts during activation and their linkage to cellular redox regulation.

RESULTS

Metabolite concentrations most significantly changed after treatment of a macrophage-like cell line (RAW) with LPS for 24 hrs were citrulline (Cit) (48-fold increase), ornithine (Orn) (8.5-fold increase), arginine (Arg) (66% decrease), and aspartic acid (Asp) (73% decrease). The ratio Cit + Orn/Arg + Asp (CO/AA) was more sensitive to LPS stimulation than other amino acid ratios commonly used to measure LPS-dependent inflammation (e.g., SAM/SAH, GSH/GSSG) and total media NOx. The CO/AA ratio was also the first ratio to change significantly after LPS treatment (4 hrs). Changes in the overall metabolomic profile over time indicated that metabolic pathways shifted from Arg catabolism to thiol oxidation.

CONCLUSIONS

Simultaneous quantification of Arg and SAA metabolic pathway shifts following LPS challenge of macrophage indicate that, in this system, the Arg-Citrulline/NO cycle and arginase pathways are the amino acid metabolic pathways most sensitive to LPS-challenge. The cellular (Cit + Orn)/(Arg + Asp) ratio, which summarizes this pathway, was more responsive to lower concentrations of LPS and responded earlier than other metabolic biomarkers of macrophage activation including GSH redox. It is suggested that the CO/AA ratio is a redox- independent early biomarker of macrophage activation. The ability to measure both the CO/AA and GSH-redox ratios simultaneously permits quantification of the relative effects of LPS challenge on macrophage inflammation and oxidative stress pathways. The use of this assay in humans is discussed, as are clinical implications.

Role of gamma-glutamyl transferase (GGT) in diagnosis of impaired glucose tolerance and metabolic syndrome: a prospective cohort research from the Kerman Coronary Artery Disease Risk Study (KERCADRS)

AIMS

The important role of raised serum gamma-glutamyl transferase (GGT) for predicting diabetes mellitus and insulin resistance is clear; however relationship between increased level of GGT and impaired glucose tolerance (IGT) is now hypothesized. We aimed to show the importance of GGT measurement in diagnosis of IGT.

MATERIALS AND METHODS

Two hundred persons were randomly selected from the Kerman Coronary Artery Disease Risk Study (KERCADRS), as a population-based study. All participants underwent GGT analysis test, besides measuring risk factors and components of metabolic syndrome (MS).

RESULTS

The increase in GGT was correlated with increased prevalence of IGT and MS and its different components. In multivariable analysis, a high GGT was positively associated with the presence of IGT after adjustment for age, sex and MS diagnostic criteria. The area under curve (AUC) for GGT was 0.722 for discriminating IGT from normal condition, and 0.847 for discriminating MS from normal status. In ROC curve analysis, the optimal cut-off value for GGT to discriminate IGT from normal condition was 20.5 IU with the sensitivity of 71.6% and the specificity of 66.1%. The best cutoff value for GGT to discriminate MS from normal condition was also 16.5 IU with the sensitivity and specificity of 78.4% and 78.4%, respectively.

CONCLUSION

The measuring GGT can be a sensitive method for early diagnosis and predicting IGT and MS from normal condition. Because this diagnostic test is a low-cost, highly sensitive, accurate and frequently used laboratory test, its measurement is recommended as a useful marker of both IGT and MS.

Biomarkers of oxidative stress and personalized treatment of pulmonary tuberculosis: emerging role of gamma-glutamyltransferase

Background. The objectives were (i) to evaluate the impact of acute pulmonary tuberculosis (PTB) and anti-TB therapy on the relationship between AST, ALT, and GGT levels in absence of conditions related to hepatotoxicity; (ii) to evaluate the rate and the time of alterations of AST, ALT, and GGT. Design and Methods. A prospective followup of 40 adults (21 males; mean age of 34.7 ± 5.8 years) with active PTB on initial phase and continuation phase anti-TB. Results. Only 3% (n = 1) developed a transient and benign ADR at day 30 without interruption of anti-TB treatment. Within normal ranges, GGT decreased significantly from day 0 to day 60, while AST and ALT increased significantly and respectively. During day 0–day 60, there was a significant, negative, and independent association between GGT and AST. Conclusion. The initial two months led to significant improvement of oxidative stress. Values of oxidative markers in normal ranges might predict low rate of ADR.

Serum gamma-glutamyltransferase concentration correlates with Framingham risk score in Koreans

Gamma-glutamyltransferase (GGT) is a novel coronary artery disease (CAD) risk factor, but its use as an independent factor for CAD risk prediction remains unclear in Asian population. This study examined the association between serum GGT concentration and Framingham risk score (FRS) in the Korean population. This cross-sectional study was performed on 30,710 Koreans. Besides FRS, body mass index, fasting blood glucose, liver enzymes, lipid profile, uric acid and high sensitive C-reactive protein data were used. The study subjects were grouped into quartiles according to the levels of GGT. Analyses relating GGT to FRS ≥ 20% utilized multiple confounders adjusted logistic regression. Positive correlations were established between log-transformed GGT concentration and FRS (r = 0.38; P < 0.001). Increasing the quartile of serum GGT concentration was significantly associated with linear increasing trends in FRS (P-trend < 0.001). Compared to the lowest baseline GGT category, age-gender adjusted odd ratios for FRS ≥ 20% were significantly increased from the lowest to highest GGT quartiles; these results remained significantly after adjustments for multiple confounders. Increased GGT concentration is associated with the increase in FRS. Serum GGT may be helpful to predict the future risk of CAD.

Liver involvement during influenza infection: perspective on the 2009 influenza pandemic

Please cite this paper as: Papic et al. (2011) Liver involvement during influenza infection: perspective on the 2009 influenza pandemic. Influenza and Other Respiratory Viruses 6(3), e2–e5.

Elevation of liver transaminase levels is a frequent observation during systemic infections. The aim of our study was to investigate liver damage during pandemic 2009 influenza A/H1N1 infection in comparison with seasonal influenza. Serum levels of aspartate aminotransferase, alanine aminotransferase, and gamma‐glutamyl transpeptidase (GGT) were significantly higher in patients with pandemic influenza compared to seasonal influenza, which was strongly correlated with hypoxia. Moreover, a positive correlation between C‐reactive protein and serum GGT, alkaline phosphatase, and lactate dehydrogenase was noticed. Our findings support the hypothesis that the pandemic 2009 influenza A/H1N1 is an illness with a significant immune response to infection leading to hepatocellular injury.

Circulating interleukin-1β and interleukin-6 concentrations are closely associated with γ-glutamyltranspeptidase activity in middle-aged Japanese men without obvious cardiovascular diseases

Interleukin (IL)-1β and IL-6 expressions are known to be induced by oxidant stress. In the present study, we examined the relationships between these interleukins and the activity of γ-glutamyltranspeptidase (γ-GTP), which was recently reported as a source of oxidant stress production, in the circulating blood of middle-aged Japanese men without obvious cardiovascular diseases. We conducted a cross-sectional study of 317 Japanese men without obvious cardiovascular diseases aged 40 to 69 years (mean ± SD, 58.6 ± 7.6 years) who participated in health checkups in Japan. We analyzed their clinical parameters in serum, lifestyle factors, and plasma IL-1β and IL-6 concentrations. We compared the relationships between these interleukin concentrations and the clinical parameters and lifestyle factors by Spearman correlation coefficients. Stepwise multiple linear regression analyses for interleukins based on the other parameters and γ-GTP, which were classified into 3 groups according to the concentrations, were performed. Interleukin-1β and IL-6 concentrations were closely associated with γ-GTP activity but less associated with alanine aminotransferase and aspartate aminotransferase activities by Spearman correlation coefficients. Stepwise multiple linear regression analyses showed that γ-GTP activity was the explanatory variable for elevated IL-1β and IL-6 concentrations. As natural logarithms, the IL-1β and IL-6 concentrations were estimated to be 1.734- and 1.157-fold higher, respectively, in subjects with high γ-GTP activity ranges than in subjects with a low γ-GTP activity range. The present results show that circulating IL-1β and IL-6 concentrations are strongly and independently associated with γ-GTP activity in middle-aged Japanese men without obvious cardiovascular diseases.

Alanine aminotransferase is associated with metabolic syndrome independently of insulin resistance

BACKGROUND

Few studies have examined the effect of insulin resistance on the association between alanine aminotransferase (ALT) and metabolic syndrome. The association between ALT levels and metabolic syndrome were determined, independently of insulin resistance in Korean populations.

METHODS AND RESULTS

The association between ALT and metabolic syndrome were examined in 28,456 subjects who visited 7 Health Promotion Centers at University Hospitals in Korea from 2006 to 2008. HOMA-IR index was used to represent insulin resistance index. ALT levels were found to be positively associated with metabolic syndrome after adjusting for age, alcohol intake, and smoking status. Furthermore, when additional adjustment was made for insulin resistance, this association between ALT and metabolic syndrome, although slightly attenuated, remained strongly significant. Subjects in the highest ALT quartile were found to have a higher risk of having metabolic syndrome than those in the lowest quartile (odds ratio (OR)=4.45, 95% confidence interval (CI)=3.96-4.99 for men and OR=3.51, 95%CI=2.73-4.52 for women). In addition, the association between ALT level and the risk of metabolic syndrome was significantly higher in the relatively low risk group.

CONCLUSIONS

ALT levels were found to be significantly associated with metabolic syndrome independently of insulin resistance and with an interaction by age. Further cohort studies are needed to determine the usefulness of ALT levels for predicting the risk of metabolic syndrome.

Studies of gamma-glutamyl transferase in alpha-1 antitrypsin deficiency

Gamma-glutamyl transferase (GGT) is a clinical marker of biliary disease, but is also of importance in anti-oxidant metabolic pathways and, consequently, is a potential biomarker of oxidative stress in COPD. Serum GGT is increased in alpha-1 antitrypsin deficiency (AATD) but this could reflect a hepatic, systemic or pulmonary origin. We aimed to investigate the relationship between serum GGT, lung disease, liver disease and mortality in subjects with AATD. Serum GGT was measured at the baseline assessment in 334 PiZ subjects from the UK AATD registry, and related to static lung function, chronic bronchitis, sputum purulence, history of acute exacerbations, smoking status, mortality, alcohol consumption, cirrhosis and serum markers of liver disease. GGT correlated with airflow obstruction and was associated with chronic bronchitis. GGT levels were higher in current smokers compared with ex-smokers and never smokers, and in non-survivors compared with survivors. Although GGT related to alcohol consumption and established liver disease, it was independently related to FEV(1), mortality, smoking history and male gender. In conclusion, although serum GGT reflects the presence of liver disease it is independently associated with airflow obstruction and mortality. Further studies are needed to establish the role of GGT in oxidative lung injury, and its use as a potential biomarker in chronic inflammatory lung disease.

Cigarette smoking and serum liver enzymes: the role of alcohol and inflammation

BACKGROUND AND AIMS

Smoking may affect the liver through inflammatory pathways and may aggravate the pathogenic effects of alcohol on the liver. We have examined the relationship between cigarette smoking and liver enzymes and the role of alcohol and C-reactive protein (CRP), a marker of inflammation.

METHODS

The subjects consisted of 4595 men aged 40-59 y with no history of coronary heart disease drawn from general practices in 24 British towns.

RESULTS

Cigarette smoking was significantly associated with increased levels of gamma-glutamyl transferase (GGT) and alkaline phosphatase (ALP) (P < 0.0001) and was inversely associated with increased aspartate aminotransferase (AST) after adjustment for alcohol intake, body mass index and physical activity. Compared with never smokers, heavy cigarette smokers (> or =40/day) were associated with increased odds of elevated GGT (> or =23 IU/L) (adjusted odds ratio [OR] 1.56 [1.08, 2.27]), which was abolished after adjustment for CRP (adjusted OR 1.27 [0.87, 1.86]). There was a significant interaction between smoking and alcohol on GGT. In the absence of heavy drinking, there was no association between smoking and GGT after adjustment for CRP. Among heavy drinkers, smoking was associated with increased levels of GGT independent of CRP. Smoking was associated with increased odds of elevated ALP (> or =11 IU/L) (adjusted OR 3.95 [2.77, 5.62]), which persisted after adjustment for CRP and white cell count (adjusted OR 2.90 [1.99-4.23]), possibly reflecting increased bone cell activity.

CONCLUSION

The findings suggest that cigarette smoking does not cause liver injury, but may enhance the effects of alcohol on liver cell injury in heavy drinkers.

Association of gamma-glutamyltransferase with incidence of type 2 diabetes in Japan

The aim of this research was to examine the association of gamma-glutamyltransferase (GGT) and its interactions with alcohol consumption (alcohol), body mass index (BMI) and/or alanine aminotransferase (ALT) on the incidence of type 2 diabetes (DM) in Japan. Data from annual health examinations obtained from 1995 to 2005 were analyzed. The total number of subjects in this cohort was 39,563. Hazard ratios (HRs) were calculated by Cox regression analysis. GGT levels were positively associated with the incidence of DM in both men and women, after adjustment for several variables, including alcohol, BMI and ALT. Among women, the association was stronger in non-drinkers than in drinkers due to a significant interaction of GGT and alcohol. In non-drinkers, the HRs of the third and fourth GGT quartiles in women and the fourth GGT quartile in men were significantly higher than those of the first GGT quartile. The association between BMI and the incidence of DM was enhanced by increased GGT levels in women. When GGT levels were in the second to fourth quartiles, the HRs of obese subjects were significantly higher than those of underweight subjects. Conversely, obesity was no longer a significant risk factor for DM when GGT level was in the first quartile. Increased GGT levels were associated with the development of DM after adjustment for several possible confounding factors. The association between GGT and DM in non-drinkers was significantly stronger than that in drinkers. Furthermore, in women, obesity is no longer a risk factor for DM when GGT level is low.

Impact of metabolic syndrome on elevated serum alanine aminotransferase levels in the Japanese population

Measurement of the serum alanine aminotransferase (ALT) level is used as an initial test for detection of liver diseases, and recent studies have also highlighted its potential value as a measure of overall health and survival as a marker of an increased risk of metabolic disorder. This study was designed to clarify the prevalence of elevated ALT levels in the Japanese population and to assess factors associated with ALT elevation. The subjects were 2165 individuals aged 40 to 85 years who participated in a Japanese community-based study referred to as the Takahata Study. Serum ALT levels and factors associated with ALT elevation were investigated. Among 2087 subjects who were negative for hepatitis B and C, the rates of elevated ALT greater than 30 U/L in men and greater than 25 U/L in women were 217 (22.7%) of 957 and 239 (21.2%) of 1130, respectively. These ALT cutoff levels had a specificity of more than 80% for exclusion of subjects with none or 1 of 3 metabolic risk factors: hypertension, lipid metabolism abnormality, and hyperglycemia. Multivariate analysis revealed 5 factors with a significant association with ALT elevation in men (n = 957): high gamma-glutamyltranspeptidase, low adiponectin, high low-density lipoprotein cholesterol, high body mass index, and high homeostasis model assessment insulin resistance index. Similarly, 4 factors were significantly associated with ALT elevation in women (n = 1130): high gamma-glutamyltranspeptidase, low adiponectin, high body mass index, and high homeostasis model assessment insulin resistance index. These results suggest that elevated ALT levels in the Japanese population older than 40 years have a strong association with metabolic syndrome-related features including obesity and insulin resistance.

The importance of gamma-glutamyltransferase activity in patients with coronary artery disease

BACKGROUND

In this study, we sought to investigate the relation of gamma-glutamyltransferase (GGT) levels with the significance of coronary artery disease (CAD), clinical presentation, left ventricular (LV) function, and inflammatory activity.

METHODS

A total of 235 patients (mean age: 60.1 +/- 10.5 years, 166 [70%] males) who had coronary angiography were included in the study. Patients who had CAD constituted the study group (Group 1, n=189) and patients who had insignificant coronary disease or normal coronary activity constituted the control group (Group 2, n=46).

RESULTS

GGT levels were higher in Group 1 than Group 2 (38.7 +/- 30.9 U/L versus 27.5 +/- 17.5 U/L, p =0.025). Left ventricular ejection fraction (LVEF) was lower in Group 1 than Group 2 (52.6% +/- 11.7% versus 58.8% +/- 11.3%, p < 0.002). GGT activity (40.2 +/- 32.5 U/L versus 29.1 +/- 18.3 U/L, p < 0.002) and c-reactive protein (CRP) levels (33.9 +/- 43.6 mg/dl versus 17.8 +/- 29.8 mg/dl, p < 0.002) were higher, LVEF (52.6% +/- 12.1% versus 56.5% +/- 11.0%, p =0.021) was lower in patients with acute coronary syndrome compared with stable CAD group. In regression analysis, CRP levels (p < 0.0001, odds ratio [OR]=3.77, 95% confidence interval [CI] 0.10 < OR < 0.32), LVEF (p =0.016, OR=- 2.44, 95% CI - 0.95 < OR < - 0.10) and LV end-diastolic pressure (p =0.015, OR=4.31, 95% CI - 1.19 < OR < - 0.13) were independent predictors of GGT activity.

CONCLUSIONS

The increased GGT activity is related to LV function, clinical stability, and inflammatory activity rather than the severity of CAD. Measurement of GGT activity may be useful in predicting cardiovascular risk.

Association between serum gamma-glutamyl transferase level and prehypertension among community-dwelling men

Serum gamma-glutamyl transferase (GGT) activity is a general clinical marker of excessive alcohol consumption, and GGT reflects changes in oxidative stress and implicated in the progression of hypertension. Recent guidelines classify persons with above-optimal blood pressure (BP) but not clinical hypertension as having prehypertension for a systolic BP (SBP) of 120 to 139 mmHg and/or a diastolic BP (DBP) of 80 to 89 mmHg; however, only limited data are available on the association between serum GGT and this entity among community-dwelling men in Japan. We performed a cross-sectional study to examine whether serum GGT was associated with prehypertension. Study participants (754 men, age 56 +/- 15 years) without a clinical history of stroke, transient ischemic attack, myocardial infarction, angina, or renal failure were recruited from a single community. Thirty-seven percent of participants had prehypertension and 39.3% had hypertension. Multiple regression analysis using SBP and DBP as objective variables, adjusted for risk factors as explanatory variables, showed that log GGT was significantly and independently associated with elevated SBP (beta = 0.109, P = 0.006) and DBP (beta = 0.238, P < 0.001). Compared with participants in the lowest tertile of serum GGT (< 29 IU/L), the multivariate-adjusted odds ratio (OR) (95% CI) for prehypertension was 1.73 (1.06-2.81) for the middle tertile (29-53 IU/L) and 2.37 (1.31-4.31) for the highest tertile (> 53 IU/L). Moreover, the respective ORs for hypertension were 1.82 (1.04-3.18) and 3.11 (1.61-6.03). These results suggest that higher serum GGT levels are associated with prehypertension or hypertension in the general male population.

Association of serum gamma-glutamyltransferase with C-reactive protein levels and white blood cell count in Korean adults

BACKGROUND

Elevated gamma-glutamyltransferase (GGT) has emerged as an independent predictor of cardiovascular disease (CVD) which is increasingly viewed as an inflammatory disease. Thus, the mechanism underlying the link between elevated GGT and CVD may be inflammation.

METHODS

We examined the relationship between GGT and C-reactive protein (CRP) levels and white blood cell (WBC) count in 4562 Korean adults (2104 men, 2458 women). The odds ratio (OR) and 95% confidence interval (CI) for high CRP and WBC count (> or = 75th percentile) for both men and women were calculated across each quartile of serum GGT.

RESULTS

Results for the OR (95% CI) for high CRP levels by GGT quartiles were 1.00, 1.67 (1.21-2.29), 2.10 (1.51-2.93) and 2.51 (1.81-3.60) in men, and 1.00, 1.05 (0.65-1.68), 1.45 (0.79-2.02) and 2.16 (1.37-3.41) in women after adjustment for age, smoking status, alcohol intake, exercise, body mass index, blood pressure, fasting plasma glucose, triglyceride, high-density lipoprotein-cholesterol, and uric acid. Similarly, positive associations between serum GGT and WBC count were also observed.

CONCLUSIONS

The present study demonstrates a positive correlation between GGT and two markers of inflammation, serum CRP and WBC count. Our findings suggest that serum GGT may be a surrogate inflammatory marker and a useful additional measure in assessing cardiovascular risk.

Relationship between gamma-glutamyltransferase and metabolic syndrome in a Korean population

AIMS

To investigate associations between gamma-glutamyltransferase (GGT) and components of metabolic syndrome (MS), insulin resistance and inflammatory markers in the Korean population.

METHODS

The 3508 subjects enrolled in this survey participated in the Korean Rural Genomic Cohort (KRGC) study. Written consent was obtained from the local ethical committee. Of these participants, 1437 were men (mean age 56.9 +/- 7.9 years) and 2071 were women (mean age 55.8 +/- 8.1 years). We measured GGT levels and various biochemical markers. To examine insulin resistance status, we used the homeostasis assessment method for insulin resistance (HOMA-IR). For inflammatory marker, we used C-reactive protein (CRP) levels.

RESULTS

Serum GGT levels were significantly higher in the MS group compared to the healthy patient group [23 (5-1403) vs. 19 (5-1920) IU/l; P = 0.01]. The prevalence of MS and adjusted relative risk were both significantly increased from the lowest to highest GGT quartiles; these results persisted after adjustments for multiple confounders. Positive correlations were established between GGT and HOMA-IR or CRP.

CONCLUSION

These results suggest that GGT levels may be a surrogate marker of insulin resistance, inflammation and MS.