Sensory properties of rehydrated Toona sinensis shoots after dehydrated by different drying methods and association with gamma-glutamyl transferase reaction

Sulfur-containing compounds are responsible for the aroma of Toona sinensis shoot (TS). In this study, vacuum-freeze-drying (VFD), microwave-drying (MD), and hot-air-drying at 100 and 40 °C (HAD100 and HAD40, respectively), were applied to dehydrate perishable TS for preservation. VFD-TS retained most aroma of fresh/raw TS after rehydration. The content of sulfur-containing compounds reached to 118.00 µg/g with leading by methyl thiirane, (E,E)/(E,Z)/(Z,Z)-bis-(1-propenyl) disulfides, and (Z)/(E)-2-mercapto-3,4-dimethyl-2,3-dihydrothiophenes accounting for 86.33 %. They were undetected in the rehydrated MD-TS and HAD100-TS, as the indigenous enzymes in TS were deactivated under their dehydration conditions. Interestingly, the sulfur-containing compounds was restored by 77.47 % after the TS was treated by gamma-glutamyl transferase (GGT). Thus, the release of sulfur-containing compounds from TS could depend on GGT reaction. It was different from alliaceous vegetables relying on alliinase reaction. The results revealed the aroma formation in TS and provided an approach to enhance the aroma of TS dried by different methods.

Real-world Outcomes and Predictive Biomarkers for 177Lutetium Prostate-specific Membrane Antigen Ligand Treatment in Metastatic Castration-resistant Prostate Cancer: A European Association of Urology Young Academic Urologists Prostate Cancer Working Group Multi-institutional Observational Study

BACKGROUND

The European Association of Urology guidelines include the lutetium-177 (177Lu) PSMA-617 prostate-specific membrane antigen (PSMA) ligand as a therapy option for metastatic castration-resistant prostate cancer (mCRPC). A major challenge in clinical practice is to pursue a personalized treatment approach based on robust predictive biomarkers.

OBJECTIVE

To assess the performance of 177Lu PSMA in real-world practice and to elaborate clinical biomarkers for evaluating treatment responses.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a retrospective observational study including 233 patients with mCRPC treated with 177Lu PSMA in eight high-volume European centers.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Baseline characteristics and clinical parameters during and after 177Lu PSMA treatment were documented. Correlations to treatment response were analyzed using χ2 and log-rank tests, with differences between groups with and without disease progression calculated using a Mann-Whitney U test. Univariate and multivariate-adjusted hazard ratios (HRs) were measured using Cox proportional hazards models.

RESULTS AND LIMITATIONS

A prostate-specific antigen (PSA) decrease of ≥30% was observed in 41.7%, 63.5%, and 77.8% of patients after the first, second, and third treatment cycle, respectively. Restaging performed via PSMA positron emission tomography-computed tomography revealed that 33.7% of patients had an imaging-based response, including two patients with a complete response, while 13.4% had stable disease. The median time to progression was 5 mo and the median time until the start of a consecutive antineoplastic therapy was 8.5 mo. Of importance, a PSA decrease ≥30% after the first two cycles of 177Lu PSMA (1 cycle: p = 0.0003; 2 cycles: p = 0.004), absolute PSA after the first three cycles (1 cycle: p = 0.011; 2 cycles: p = 0.0005; 3 cycles: p = 0.002), and a PSA doubling time >6 mo (p = 0.009) were significantly correlated to treatment response. Furthermore, gamma-glutamyl transferase ≤31 U/L at the start of 177Lu PSMA therapy was correlated with 1.5 times higher risk of progression for patients without but not with visceral metastases (p = 0.046).

CONCLUSIONS

177Lu PSMA is an effective treatment option in mCRPC in the real-world setting. A PSA decrease ≥30% after the first two cycles is an early marker of response that can be easily implemented in clinical practice.

PATIENT SUMMARY

177Lu PSMA is a radioactive agent approved for treatment of advanced prostate cancer. We reviewed its use outside of clinical trials for patients treated at eight European centers. We found that 177Lu PSMA is an effective treatment option in real-world practice. A PSA (prostate-specific antigen) decrease of ≥30% after the first two therapy cycles is an early indicator of response to treatment and can be used in personalizing treatments for patients.

Quantification of CD3, FoxP3, and granzyme B immunostaining in canine renal cell carcinoma

Tumor-infiltrating lymphocyte (TIL) density plays an important role in anti-tumor immunity and is associated with patient outcome in various human and canine malignancies. As a first assessment of the immune landscape of the tumor microenvironment in canine renal cell carcinoma (RCC), we retrospectively analyzed clinical data and quantified CD3, FoxP3, and granzyme B immunostaining in formalin-fixed paraffin-embedded tumor samples from 16 dogs diagnosed with renal cell carcinoma treated with ureteronephrectomy. Cell density was low for all markers evaluated. Increased numbers of intratumoral FoxP3 labelled (+) cells, as well as decreased granzyme B+: FoxP3+ TIL ratio, were associated with poor patient outcomes. Our initial study of canine RCC reveals that these tumors are immunologically cold and Tregs may play an important role in immune evasion.

Relationship between traditional risk factors for hypertension and systolic blood pressure in the Tohoku Medical Megabank Community-based Cohort Study

Risk factors for hypertension have been emphasized in the Japanese Society of Hypertension Guidelines for the Management of Hypertension. However, large-scale studies on the association of smoking, potassium excretion, and gamma-glutamyl transferase level with BP in the Japanese population are limited. We conducted a cross-sectional study to examine the association between hypertension risk factors and systolic blood pressure in the Tohoku Medical Megabank Community-based Cohort Study (23,446 men and 38,921 women aged ≥20 years). A model adjusted for age, body mass index, smoking status, drinking status, estimated daily salt intake, potassium excretion, (or urinary sodium-to-potassium ratio), gamma-glutamyl transferase, physical activity, education level, status of damage to homes during the Great East Japan Earthquake, and residential areas was used. The average age and systolic blood pressure were 62.5 (10.3) years for men and 59.6 (11.3) years for women, 128.9 (16.7) mmHg for men and 124.7 (17.5) mmHg for women, respectively. Body mass index estimated daily salt intake, urinary sodium-to-potassium ratio and gamma-glutamyl transferase levels were positively associated with systolic blood pressure. Compared with never-drinkers, current drinkers who consumed 23-45 g/day and ≥46.0 g/day had significantly increased systolic blood pressure. Conversely, current smokers (1-10 cigarettes/day and 11-20 cigarettes/day) were inversely associated with systolic blood pressure compared to never-smokers. Overall, systolic blood pressure was associated with gamma-glutamyl transferase and hypertension risk factors, including body mass index, alcohol consumption, estimated daily salt intake, urinary sodium-to-potassium ratio, and potassium excretion. Our findings support the notion that lifestyle modifications should be attempted to prevent hypertension.

Association between maternal obesity, essential fatty acids and biomarkers of fetal liver function

Maternal obesity and the imbalance in linoleic acid (C18:2 n-6, LA) and alpha-linolenic acid (C18:3 n-3, ALA) levels are related with hepatic disturbances in the offspring. However, whether these alterations are present during fetal life is not well understood. Obese and normal weight pregnant women were recruited to determine fatty acids (FAs) consumption, FAs profile (in maternal erythrocytes, placenta and neonatal very low-density lipoproteins VLDL) and biomarkers of fetal liver function, such as gamma-glutamyl transferase (GGT), alpha-fetoprotein (AFP) and albumin, in umbilical cord blood. Stearic acid (C18:0, ST) was lower, and total n-3 FAs tended to be lower in umbilical cord VLDLs of obese women compared to controls. Independently of maternal obesity, GGT levels in umbilical cord blood was positively correlated with the LA content and negatively correlated with the ALA content in maternal erythrocytes. We conclude that maternal obesity and its imbalance of LA and ALA are associated with changes in biomarkers of fetal liver function.

The association between urinary polycyclic aromatic hydrocarbon metabolites and liver function among US population: a cross-sectional study

Most studies have focused on the pulmonary toxicity of inhaled PAHs to date; therefore, their hepatotoxic consequences are yet unknown. The main aim of this study is to examine the association between urinary polycyclic aromatic hydrocarbons (PAHs) and liver function parameters among the US population. The data included in this study were from the National Health and Nutritional Examination Survey (NHANES) 2003-2016. Finally, we included 2515 participants from seven cycles of the NHANES. Logistic regression was performed to calculate the association between each PAH and liver function parameters (elevated vs. normal) with odds ratio (OR) and 95% confidence intervals (CIs), along with adjustment for confounding variables. P < 0.05 was considered to indicate a statistically significant difference. All analyses were performed using R software 4.0.1. In the present study, all 2515 individuals were aged ≥ 18 years, 1211 males, and 1304 females. The average age normal was 45.56 ± 20.20, and the elevated was 46.04 ± 19.73 years, respectively. The results of logistic regression indicated that increased 9-hydroxyfluorene (OR  = 2.11, 95% CI = [1.52, 2.95], P < 0.001), 2-hydroxyfluorene (OR  = 1.61, 95% CI = [1.23, 2.11], P < 0.001), and 3-hydroxyfluorene (OR  = 1.54, 95% CI = [1.21, 1.95], P < 0.001) were associated with elevated GGT. In conclusion, 9-hydroxyfluorene is associated with elevated GGT level, and the effect of 9-hydroxyfluorene on GGT is modified by other PAHs, which means that 9-hydroxyfluorene has a greater influence on GGT when other PAHs are increased.

Association between serum gamma glutamyl transferase and fasting blood glucose in Chinese people: A 6-year follow-up study

AIMS/INTRODUCTION

In this study, we aimed to investigate the relationships between gamma-glutamyl transferase (GGT) and fasting blood glucose (FBG) during a 6-year follow-up study of participants, and to determine whether GGT is a risk factor for FBG.

MATERIALS AND METHODS

A total of 1,369 individuals from the health examination survey in the urban area of Xuzhou, central China, were followed up for 6 years. The patients were divided into four groups based on their baseline GGT levels (in quartiles). The one-way analysis of variance (anova) method was used to compare the differences between the variables and baseline. The relationship between GGT and FBG levels was investigated using repeated measurements anova.

RESULTS

The grouping of baseline GGT levels affected the changes in blood glucose during the 6-year follow-up study. In the GGT quartile subgroups, the annual mean increase in FBG levels showed a positive relationship with baseline GGT levels. This trend was even more aggregated in the highest baseline GGT group. Interactions among time course, baseline FBG and GGT groups in different participants together affected the change of FBG levels during the follow-up period. The repeated measures anova suggested that different baseline GGT groups were still significantly associated with increased FBG levels. GGT is a risk factor that affects FBG levels(P < 0.001).

CONCLUSIONS

The annual mean increase in FBG levels showed a positive relationship with baseline GGT levels. Higher baseline GGT levels resulted in a faster annual mean increase in FBG. Thus, GGT can be used for the early detection of FBG-related disorders of glucose metabolism for clinical application.

Design and evaluation of novel analogs of 2-amino-4-boronobutanoic acid (ABBA) as inhibitors of human gamma-glutamyl transpeptidase

Inhibitors of gamma-glutamyl transpeptidase (GGT1, aka gamma-glutamyl transferase) are needed for the treatment of cancer, cardiovascular illness and other diseases. Compounds that inhibit GGT1 have been evaluated in the clinic, but no inhibitor has successfully demonstrated specific and systemic GGT1 inhibition. All have severe side effects. L-2-amino-4‑boronobutanoic acid (l-ABBA), a glutamate analog, is the most potent GGT1 inhibitor in vitro. In this study, we have solved the crystal structure of human GGT1 (hGGT1) with ABBA bound in the active site. The structure was interrogated to identify interactions between the enzyme and the inhibitor. Based on these data, a series of novel ABBA analogs were designed and synthesized. Their inhibitory activity against the hydrolysis and transpeptidation activities of hGGT1 were determined. The lead compounds were crystalized with hGGT1 and the structures solved. The kinetic data and structures of the complexes provide new insights into the critical role of protein structure dynamics in developing compounds for inhibition of hGGT1.

Diagnostic values of plasma matrix metalloproteinase-7, interleukin-8, and gamma-glutamyl transferase in biliary atresia

Biliary atresia (BA) is a severe cholestatic liver disease in children featuring cholestasis and liver fibrosis. The early diagnosis of BA is still challenging. This study aimed to evaluate the diagnostic values of matrix metalloprotease-7 (MMP-7), interleukin-8 (IL-8), and gamma-glutamyl transferase (GGT) in BA. Infants diagnosed with BA and non-BA between 2013 and 2018 were retrospectively analyzed. Plasma levels of MMP-7, IL-8, and GGT were measured in these infants. The receiver operating characteristic (ROC) curves and area under the ROC curve (AUC) were used to assess the diagnostic values of MMP-7, IL-8, and GGT. The expression of MMP-7 and IL-8 in the livers was detected by immunofluorescence staining. A total of 229 infants were enrolled in this study: 156 BA infants and 73 non-BA infants including 16 ones with infantile hepatitis syndrome. The plasma levels of MMP-7, IL-8, and GGT in BA infants had a median of 11.8 ng/mL (interquartile range, IQR: 5.3-57.5), 1.5 ng/mL (IQR: 1.0-2.8), and 381.0 U/L (IQR: 197.0-749.0), respectively, which were higher than non-BA subjects [MMP-7, 4.4 ng/mL (IQR: 3.3-6.1); IL-8, 0.7 ng/mL (IQR: 0.5-1.0); GGT, 59.0 U/L (IQR: 26.0-124.0)]. The AUC values of MMP-7, IL-8, and GGT for the diagnosis of BA were 0.8035, 0.8083, and 0.9126, respectively. The AUC values of MMP-7 + IL-8, MMP-7 + GGT, IL-8 + GGT, and MMP-7 + IL-8 + GGT for the diagnosis of BA were 0.8248, 0.9382, 0.9168, and 0.9392, respectively. The AUC values of MMP-7, IL-8, and GGT for differentiating BA infants with cholic stool from non-BA infants with cholic stool were 0.8006, 0.8258, and 0.9141, respectively. The expression of MMP-7 and IL-8 was increased in the cholangiocytes in BA livers.   Conclusion: Plasma MMP-7, IL-8, and GGT alone or a combination of them has good accuracy to differentiate BA from non-BA and may be reliable biomarkers for BA. What is Known: • Biliary atresia (BA) is a severe cholestatic liver disease in children featuring cholestasis and progressive liver fibrosis. • Although early diagnosis of BA is crucial for good outcomes, it remains a clinical challenge. What is New: • Plasma MMP-7, IL-8, and GGT alone or a combination of them has good accuracy to differentiate BA from non-BA. • Plasma MMP-7, IL-8, and GGT have good accuracy for differentiating BA infants with cholic stool from non-BA infants with cholic stool.

Development and validation of a novel nomogram and risk score for biliary atresia in patients with cholestasis

BACKGROUND

Timely discriminating biliary atresia (BA) from other causes of cholestasis is important but challenging.

AIMS

To develop a useful diagnostic nomogram and a simplified scoring system to diagnosing BA.

STUDY DESIGN

All medical records of the patients who were consecutively admitted to our institution with cholestasis from March 2016 to December 2020 were retrospectively searched. The patients were allocated to the derivation cohort (n = 343) and the validation cohort (n = 246). Multivariable logistic regression models were used to construct the nomogram. The nomogram was validated in both cohorts. The simplified risk score was derived from the nomogram.

RESULTS

The nomogram was constructed based on presence of clay stool, gallbladder length, gallbladder emptying index, shear wave elastography value, and gamma-glutamyl transferase level. This model showed good calibration and discrimination ability, with the C-index of 0.968 (95% CI: 0.951-0.984). The discriminating ability is most prominent in the 61-90 days group, with AUC of 0.982 (95% CI: 0.955-1.000). The simplified risk score identified most patients with very high or low risk of BA, and was capable of exempting 64.3% non-BA patients from intraoperative cholangiogram procedure.

CONCLUSIONS

This novel diagnostic nomogram had good discrimination and calibration abilities. The simplified scoring system showed significant clinical utility.

Gamma-glutamyl transferase levels are associated with the occurrence of post-stroke cognitive impairment: a multicenter cohort study

Background

Gamma-glutamyl transferase (GGT) is involved in maintenance of physiological concentrations of glutathione in cells, and protects them from oxidative stress-induced damage. However, its role in post-stroke cognitive impairment (PSCI) remains unknown. Here, we investigated the effects of serum GGT on PSCI.

Methods

We conducted a prospective, multicenter cohort study. A total of 1, 957 participants with a minor ischemic stroke or transient ischemic attack whose baseline GGT levels were measured were enrolled from the Impairment of Cognition and Sleep (ICONS) study of the China National Stroke Registry-3 (CNSR-3). They were categorized into four groups according to quartiles of baseline GGT levels. Cognitive functions were assessed using the Montreal Cognitive Assessment (MoCA) approach. Multiple logistic regression models were performed to evaluate the relationship between GGT and PSCI at 3 months follow-up.

Results

Among the 1957 participants, 671 (34.29%) patients suffered PSCI at 3 months follow-up. The highest GGT level quartile group exhibited a lower risk of PSCI in the fully adjusted model [OR (95% CI): 0.69 (0.50-0.96)], relative to the lowest group. Moreover, incorporation of GGT to the conventional model resulted in slight improvements in PSCI outcomes after 3 months (NRI: 12.00%; IDI: 0.30%).

Conclusions

Serum GGT levels are inversely associated with the risk of PSCI, with extremely low levels being viable risk factors for PSCI.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02587-4.

The utility of shear wave elastography and serum biomarkers for diagnosing biliary atresia and predicting clinical outcomes

To investigate the utility of liver stiffness measurement by shear wave elastography (SWE) and several commonly used biomarkers in differentiating biliary atresia (BA) from other causes of cholestasis (non-BA) patients within 45 days and in predicting the postoperative prognosis. A consecutive series of medical records of patients presenting with cholestasis within 45 days in our institution between February 2016 and December 2020 was collected. The BA diagnosis was confirmed by intraoperative cholangiography (IOC). Other causes of cholestasis were confirmed by IOC, liver biopsy, genetic analysis, or recovery after conservative treatment. Preoperative and postoperative data were analyzed. A total of 156 patients were included, consisting of BA (n = 83) and non-BA (n = 73) cases. SWE and serum gamma-glutamyl transferase (GGT) showed better discriminative utility. The optimal cutoff values for SWE and GGT were > 7.10 kPa and > 195.4 U/L, with AUC of 0.82 (95% CI, 0.76-0.89; p < 0.0001) and 0.87 (95% CI, 0.82-0.93; p < 0.0001), respectively. Subgroup analysis showed the increased discriminative performance of SWE with age. Multivariable logistic regression analysis showed better diagnostic performance for SWE (adjusted OR, 35.03; 95% CI, 7.12-172.50) and GGT (adjusted OR, 24.70; 95% CI, 6.55-93.18) after adjusting for other confounders. The 30-day postoperative to preoperative serum direct bilirubin (DB) level, DB (post-30:pre), of > 0.3 showed the best predictive value for the need of liver transplantation, with HR of 6.15 (95% CI 1.95-19.38, P = 0.042).Conclusion: Serum GGT level and liver stiffness measurement by SWE showed the best discriminative utility. The diagnostic performance of SWE increased with age. A DB (post-30:pre) value > 0.3 was associated with the need for liver transplantation in later life. What is Known: • Liver stiffness measurement by shear wave elastography (SWE) could help discriminate biliary atresia (BA) from other causes of cholestasis, with sensitivity of 70-90%. • The postoperative total bilirubin less than 2 mg/dL within the first 3 months was a predictor of transplant-free survival. What is New: • The diagnostic performance of liver stiffness measurement by SWE increased with age. • The 30-day postoperative direct bilirubin (DB) level to preoperative DB level, DB (post-30:pre), is a predictor for short-term clinical outcomes.

Prevalence and predictors of elevated liver enzyme levels in Mexico: The Mexican National Health and Nutrition Survey, 2016

INTRODUCTION AND OBJECTIVE

To determine the prevalence of elevated liver enzyme levels and the fatty liver index according to specific sociodemographic, clinical, anthropometric, and metabolic risk factors in Mexican adult population.

MATERIAL AND METHODS

The present analysis was conducted using data from the Mexican National Health and Nutrition Survey 2016. For the present study, 3,490 adults with complete information on liver enzymes, sociodemographic, lifestyle, and metabolic factors were analyzed. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT) levels were determined from blood samples. We computed the fatty liver Index (FLI), as a surrogate marker of non-alcoholic fatty liver disease. The associations are reported as adjusted odds ratios (OR) and 95% confidence intervals (95%CI).

RESULTS

At the national level, the prevalence of high serum levels of ALT, AST, and GGT were 7.9%, 13.5, and 12.9 respectively. We observed that men had higher prevalences of altered ALT, GGT and FLI compared to women. Additionally, we observe that individuals with obesity, metabolic syndrome and insulin resistance are significantly more likely to present elevated concentrations of AST, ALT, GGT and FLI. Finally, we found that the subjects of the lowest socioeconomic level and indigenous population were more likely to present elevated levels of AST, ALT, GGT, and FLI.

CONCLUSION

In Mexico, non-alcoholic fatty liver disease affect people with obesity, diabetes, and metabolic syndrome as well as men, subjects of low socioeconomic status, subjects who live in rural areas and indigenous population. Interventions to reduce this condition should be a public health priority.

Exploring the clinical value of preoperative serum gamma-glutamyl transferase levels in the management of patients with hepatocellular carcinoma receiving postoperative adjuvant transarterial chemoembolization

Background

Preoperative serum gamma-glutamyl transferase (γ-GT) levels is significantly related to the prognosis of hepatocellular carcinoma (HCC), but its clinical value in the management of postoperative adjuvant transarterial chemoembolization (PA-TACE) has rarely been explored. This study aimed to investigate whether γ-GT levels could be taken as a biomarker to guide the management of PA-TACE in resectable HCC.

Methods

HCC patients receiving radical resection were identified through the primary liver cancer big data (PLCBD) from December 2012 to December 2015. Prognostic factors of overall survival (OS) and disease-free survival (DFS) were identified by univariate and multivariate cox analyses, and subgroup analysis was conducted between PA-TACE group and non-TACE stratified by γ-GT levels before and after 1:1 propensity score matching (PSM).

Results

γ-GT level was found to be an independent risk factor of OS and DFS in 1847 HCC patients receiving radical resection (both P < 0.05), and patients with elevated γ-GT(> 54.0 U/L) have a shortened median OS and DFS, compared with those with normal γ-GT (both P < 0.001). In the subgroup of patients with normal γ-GT, there were no significant differences between groups of PA-TACE and non-TACE in terms of median OS and DFS before and after PSM (all P > 0.05), and PA-TACE was not a significant prognostic factor of both OS and DFS before and after PSM (all P > 0.05). In the subgroup of patients with elevated γ-GT, significant differences were found between groups of PA-TACE and non-TACE in terms of median OS and DFS before and after PSM (all P < 0.05), and PA-TACE was an independent prognostic factor of both OS and DFS (all P < 0.05).

Conclusion

Currently, we concluded that patients with more advanced HCC also have more elevated γ-GT, and these patients with elevated γ-GT would be benefited more from PA-TACE after radical resection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08843-z.

Serum GGT/ALT ratio predicts vascular invasion in HBV-related HCC

BACKGROUND

The gamma-glutamyl transferase (GGT) to alanine aminotransferase (ALT) ratio has been reported as an effective predictor of the severity of hepatitis and HCC. The purpose of this study was to determine the role of the GGT/ALT ratio in the prediction of vascular invasion and survival outcomes in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).

METHODS

The risk factors for vascular invasion were determined by univariate/multivariate logistic analysis. The cut-off value of GGT/ALT in predicting vascular invasion was calculated using the receiver operating characteristic (ROC) curve. The prognostic value of GGT/ALT was examined by Cox analysis and Kaplan-Meier curves. Sensitivity analysis, such as subgroup analysis and propensity score matching (PSM), was performed to reduce potential confounding bias.

RESULTS

A high GGT/ALT ratio was identified as an independent risk factor for vascular invasion (P = 0.03). The correlation analysis suggested that higher GGT/ALT was associated with more severe tumour burdens, including vascular invasion (P < 0.001), tumour volume > 5 cm (P < 0.001), poor pathological differentiation (P = 0.042), more severe BCLC (P < 0.001) and ALBI grade (P = 0.007). In the survival analysis, a high GGT/ALT ratio was associated with poor overall survival (OS) (HR: 1.38; 95% CI 1.03, 1.87; P < 0.0001) and disease-free survival (DFS) (HR: 1.32; 95% CI 1.03, 1.87; P < 0.0001). In the subgroup analysis, similar results were consistently observed across most subgroups. In PSM analysis, GGT/ALT remained independently associated with vascular invasion (OR, 186; 95% CI 1.23, 3.33).

CONCLUSION

The GGT/ALT ratio was a potential effective factor in the prediction of vascular invasion and prognosis in patients with HBV-related HCC.

Relationship Between Elevated Hair Mercury Levels, Essential Element Status, and Metabolic Profile in Overweight and Obese Adults

The objective of the present study was to evaluate hair essential and trace element levels and metabolic risk markers in overweight and obese subjects in relation to body mercury burden. According to 2 × 2 factorial design a total of 440 adults were distributed to four groups: (i) low-Hg normal-weight subjects (n = 114); (ii) high-Hg normal weight subjects (n = 113); (iii) low-Hg overweight (BMI > 25) subjects (n = 110); (iv) high-Hg overweight (BMI > 25) subjects (n = 110). Hg-exposed groups consisted of subjects characterized by frequent seafood consumption (> 4 times/week) subsequently evaluated by hair analysis (> 0.58 μg/g). Dietary-exposed subjects were characterized by a more than 3-fold higher hair Hg content irrespectively of body weight values. Both low-Hg and high-Hg overweight subjects were characterized by significantly higher ALT activity, as well as elevated serum glucose, LDL, and triglyceride levels as compared to the respective groups of normal weight subjects. High Hg body burden had a more significant effect on metabolic parameters in overweight and obese adults. Particularly, high-Hg overweight subjects were characterized by significantly higher serum creatinine and uric acid levels, as well as increased GGT and CK activity as compared to low-Hg overweight counterparts. In addition, hair Mg, Mn, and Sr content in high-Hg overweight subjects was significantly lower than that in low-Hg normal weight and overweight examinees. In turn, high Hg levels in overweight subjects were associated with significantly higher hair Se and Zn levels when compared to unexposed overweight adults. Generally, the obtained data demonstrate that increased hair Hg levels in overweight and obese subjects is associated with adverse metabolic profile. It is proposed that observed metabolic alterations may be at least partially mediated by Hg-associated disturbances in essential trace element and mineral metabolism.

Non-linear relationship between gamma-glutamyl transferase and type 2 diabetes mellitus risk: secondary analysis of a prospective cohort study

OBJECTIVE

To investigate the association between gamma-glutamyl transferase (GGT) and type 2 diabetes mellitus (T2DM) risk.

METHODS

This was a secondary analysis based on a publicly available DRYAD dataset that included 15 444 study participants that received medical examinations at a single centre in Japan between 2004 and 2015. Crude, minimally-adjusted and fully-adjusted regression models were used to evaluate the relationship between GGT levels and T2DM risk.

RESULTS

The study participants (mean ± SD age of 43.72 ± 8.90 years; 8415 of 15 444 [54.49%] were male) were followed-up for a median of 1968 days (5.39 years). After adjusting for potential covariates, a non-linear relationship between the baseline GGT level and T2DM incidence was observed. The inflection point for T2DM risk was 10 IU/l GGT; below this point, the T2DM incidence increased by 1.18-fold per unit change in GGT. Above this point, the association between GGT and the incidence rate of T2DM became nonsignificant.

CONCLUSION

Baseline GGT exhibited a non-linear association with T2DM incidence. Elevated GGT levels should be incorporated into routine screening for individuals at high risk of T2DM, allowing for early intervention targeting GGT to potentially reduce T2DM-related morbidity.

Combined associations of liver enzymes and obesity with diabetes mellitus prevalence: The Tohoku Medical Megabank Community-based Cohort Study

BACKGROUND

Alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT) are enzymes associated with diabetes mellitus (DM) prevalence. However, limited information is available regarding the association of liver enzymes and DM consistently present in obese and non-obese individuals. We examined whether the combination of ALT and GGT enzymes is associated with the prevalence of DM regardless of obesity in a general Japanese population.

METHODS

We conducted a cross-sectional study of 62,786 participants aged ≥20 years who lived in Miyagi and Iwate, Japan. We divided all the participants into eight groups according to the ALT level (low: <30 IU/L and high: ≥30 IU/L), GGT level (low: <50 IU/L and high: ≥50 IU/L), and the presence of obesity. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using multivariable logistic regression analysis, adjusting for potential confounders, to determine associations of the combination of ALT and GGT levels and obesity with DM prevalence.

RESULTS

Overall, 6,008 participants (9.6%) had DM. Compared to non-obese individuals with low ALT and GGT levels, the participants with high ALT and GGT levels had high ORs for DM in both obese (OR 4.06; 95% CI, 3.61-4.56) and non-obese groups (OR 2.19; 95% CI, 1.89-2.52). The obese group had high ORs for DM, even at low ALT and GGT levels.

CONCLUSION

High ALT and GGT levels are associated with DM prevalence in obese and non-obese participants. This finding suggests that correcting ALT and GGT levels and controlling obesity are important for the prevention of DM.

Prognostic role of gamma-glutamyl transferase in metastatic melanoma patients treated with immune checkpoint inhibitors

BACKGROUND

Hepatic immune-related adverse events (irAE) including elevated liver function tests (transaminases) occur in 1.4-22.3% of melanoma patients receiving immune checkpoint inhibitors (ICPI) and constitute a potentially serious toxicity that is challenging to treat. In contrast to the liver transaminases alanine aminotransferase (ALT) and aspartate aminotransferase (AST), only little is known about the frequency and impact of gamma-glutamyl transferase (GGT) elevations.

METHODS

GGT determined prior to and during therapy of metastatic melanoma patients treated with ICPI were retrospectively assessed in two independent cohorts (PD-1: n = 218, Ipi + Nivo: n = 148). Overall survival (OS) and best objective response were analyzed according to baseline and immune-related GGT (irGGT) elevations during treatment.

RESULTS

In multivariate analysis, OS was reduced in patients with elevated baseline GGT (PD-1 group: hazard ratio [HR] 1.76, p = .0073; Ipi + Nivo group: HR 1.77, p = .032). Immune-related GGT elevation was recorded in 17% (PD-1 group) and 38.5% (Ipi + Nivo group). Of these patients, the majority (81 and 68%, respectively) had normal ALT and AST and showed no clinical signs of hepatotoxicity. Patients who experienced irGGT elevation had superior response (PD-1 group: odds ratio [OR] 3.57, p = .00072; Ipi + Nivo group: OR 1.74, p = .12) and OS (PD-1 group: HR 0.37, p = .0016; Ipi + Nivo group: HR 0.33, p = .00050).

CONCLUSIONS

The frequency of hepatic irAE is currently underestimated. The addition of the sensitive enzyme GGT to the laboratory panel before and during therapy with ICPI allows to detect two to three times more patients developing hepatic or hepatobiliary toxicity than known so far. Immune-related GGT elevations correlate with response and favorable survival. Precis for use in the Table of Contents The frequency of hepatotoxicity under immune checkpoint blockade is currently underestimated. We suggest the addition of gamma-glutamyl transferase to the laboratory panel in checkpoint inhibitor patients for the detection of hepatobiliary toxicity.

Non-Alcoholic Fatty Liver Disease Modifies Serum Gamma-Glutamyl Transferase in Cigarette Smokers

Background

Serum gamma-glutamyl transferase (GGT) is a marker of oxidative stress, associated with increased cardiovascular (CV) risk. The impact of smoking on oxidative stress may be aggravated in individuals with non-alcoholic fatty liver disease (NAFLD). We aimed to ascertain the association of smoking on GGT levels in the presence or absence of NAFLD.

Methods

We evaluated 6,354 healthy subjects (43 ± 10 years, 79% males) without clinical cardiovascular disease (CVD) undergoing an employer-sponsored physical between December 2008 and December 2010. NAFLD was diagnosed by ultrasound and participants were categorized as current or non-smokers by self report. A multivariate linear regression of the cross-sectional association between smoking and GGT was conducted based on NAFLD status.

Results

The prevalence of NAFLD was 36% (n = 2,299) and 564 (9%) were current smokers. Smokers had significantly higher GGT levels in the presence of NAFLD (P < 0.001). After multivariable adjustment, current smoking was associated with 4.65 IU/L higher GGT level, P < 0.001, compared to non-smokers. When stratified by NAFLD, the magnitude of this association was higher in subjects with NAFLD (β-coefficient: 11.12; 95% confidence interval (CI): 5.76 - 16.48; P < 0.001); however, no such relationship was observed in those without NAFLD (β: -0.02; 95% CI: -3.59, 3.56; P = 0.992). Overall the interaction of NAFLD and smoking with GGT levels as markers of oxidative stress was statistically significant.

Conclusions

Smoking is independently associated with significantly increased oxidative stress as measured by GGT level. This association demonstrates effect modification by NAFLD status, suggesting that smoking may intensify CV risk in individuals with NAFLD.

Preoperative Alanine Aminotransferase and Remnant Liver Volume Predict Liver Regeneration After Live Donor Hepatectomy

BACKGROUND

Regeneration of the remnant liver in early postoperative period determines the outcome in live liver donors (LLDs). The aim of the current study is to evaluate the factors that influence liver regeneration following live donor hepatectomy.

METHODS

Total liver volume (TLV), estimated graft volume (EGV), and remnant liver volume (RLV) were calculated preoperatively in a prospective study of 154 LLDs. Absolute and percentage growth of remnant liver (regeneration index) in donor was estimated at 7th postoperative day (POD) by computed tomography (CT) volumetric analysis.

RESULTS

One hundred eighteen donors underwent right hepatectomy (RH), 29 underwent left hepatectomy (LH), 6 donors had left lateral sectionectomy (LLS), and one had right posterior sectionectomy. The median percentage growth of remnant liver at the end of the first week was 46.14% (51.74%, 35.32%, and 17.38% for RH, LH, and LLS, respectively). On univariate analysis, female donors (p = 0.051), RH graft (p = 0.001), no steatosis on ultrasonography (p = 0.042), lower TLV (p = 0.029), RLV (p = < 0.001), RLV-to-body weight ratio (RLVBWR) (p = < 0.001), preoperative alanine aminotransferase (ALT) level (p = 0.017), aspartate aminotransferase (AST) (p = 0.035) and higher POD 7 alkaline phosphatase (ALP) (p = 0.033), and POD 7 gamma-glutamyl transferase GGT (p = 0.006) were found to be predictors of greater liver regeneration. Among them, lower RLV (P = 0.008), RLVBWR (p = 0.011), and preoperative ALT level (p = 0.021) were most significant factors predictive of liver regeneration on logistic regression analysis with backward elimination.

CONCLUSION

The liver regenerates rapidly in LLDs following hepatectomy. Low RLV, RLVBWR, and preoperative ALT levels were predictors of liver regeneration in the first week following donor hepatectomy.

Frequently abnormal serum gamma-glutamyl transferase activity is associated with future development of fatty liver: a retrospective cohort study

Background

Nonalcoholic fatty liver disease is characterized by excessive hepatic fat accumulation. Some individuals frequently present elevated gamma-glutamyl transferase (GGT) levels without fatty liver ultrasound images and other abnormal liver enzymes levels. However, whether these individuals are at an elevated risk for developing fatty liver is unclear. We compared fatty liver change rates and risk factors between individuals with frequently elevated GGT levels and those with normal levels.

Methods

We designed a retrospective cohort study on the basis of complete medical checkup records. One group of individuals had presented normal serum GGT levels during the observation period (Normal-GGT group, n = 2713). Another group had had abnormal elevated serum GGT levels frequently (Abnormal-GGT group, n = 264). We determined the fatty liver change incident rates before and after propensity score matching. We explored confounding factors affecting fatty changes in each group using univariate and multivariate Cox models.

Results

The change incidence rates were 5.80/1000 and 10.02/1000 person-years in the Normal-GGT and Abnormal-GGT groups, respectively. After propensity score matching, the incidence rates were 3.08/1000 and 10.18/1000 person-years in the Normal-GGT and Abnormal-GGT groups, respectively (p = 0.026). The factors associated with fatty liver changes in the Normal-GGT group included body mass index (BMI), hemoglobin, alanine aminotransferase (ALT), albumin, triglyceride (TG), fasting blood sugar, and high-density lipoprotein levels. Those in the Abnormal-GGT group were platelet counts and TG. In our multivariable analysis, BMI, ALT, albumin, and TG levels were independent predictors of fatty changes in the Normal-GGT group, and high TG level was the only independent predictor in the Abnormal-GGT group.

Conclusions

The incidence rate of fatty liver change in the Abnormal-GGT group was higher than that in the Normal-GGT group. Consecutive elevated GGT levels increase the risk for fatty liver, and high TG levels in those individuals further independently increase the risk.

Associations of linoleic acid with markers of glucose metabolism and liver function in South African adults

Background

The relation between dietary and circulating linoleic acid (18:2 n-6, LA), glucose metabolism and liver function is not yet clear. Associations of dietary and circulating LA with glucose metabolism and liver function markers were investigated.

Methods

Cross-sectional analyses in 633 black South Africans (aged > 30 years, 62% female, 51% urban) without type 2 diabetes at baseline of the Prospective Urban Rural Epidemiology study. A cultural-sensitive 145-item food-frequency questionnaire was used to collect dietary data, including LA (percentage of energy; en%). Blood samples were collected to measure circulating LA (% total fatty acids (FA); plasma phospholipids), plasma glucose, glycosylated hemoglobin (HbA1c), serum gamma-glutamyl transferase (GGT), alanine (ALT) and aspartate aminotransferase (AST). Associations per 1 standard deviation (SD) and in tertiles were analyzed using multivariable regression.

Results

Mean (±SD) dietary and circulating LA was 6.8 (±3.1) en% and 16.0 (±3.5) % total FA, respectively. Dietary and circulating LA were not associated with plasma glucose or HbA1c (β per 1 SD: − 0.005 to 0.010, P > 0.20). Higher dietary LA was generally associated with lower serum liver enzymes levels. One SD higher circulating LA was associated with 22% lower serum GGT (β (95% confidence interval): − 0.25 (− 0.31, − 0.18), P < 0.001), but only ≤9% lower for ALT and AST. Circulating LA and serum GGT associations differed by alcohol use and locality.

Conclusion

Dietary and circulating LA were inversely associated with markers of impaired liver function, but not with glucose metabolism. Alcohol use may play a role in the association between LA and liver function.

Trial registration

PURE North-West Province South Africa study described in this manuscript is part of the PURE study. The PURE study is registered in ClinicalTrials.gov (Identifier: NCT03225586; URL).

The association of plasma levels of liver enzymes and risk of gestational diabetes mellitus: a systematic review and dose-response meta-analysis of observational studies

AIMS

Relationship between liver enzymes such as gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), aspartate transaminase (AST) and alkaline phosphatase and risk of gestational diabetes mellitus (GDM) is a controversial issue. The aim of this systematic review and dose-response meta-analysis was to investigate the association between liver enzymes and risk of GDM in observational studies.

METHODS

A comprehensive systematic literature search was conducted in MEDLINE/PubMed, SCOPUS and Web of Science databases up to September 2019. Combined odds ratios (ORs) with 95% confidence intervals (CIs) were evaluated by DerSimonian and Laird random-effects models. Dose-response analyses of these relationships were also carried out.

RESULTS

Eight studies with 25,451 participants containing 2549 cases were included in this study. Pooled results showed a significant association between GGT levels and risk of GDM (OR 2.10, 95% CI 1.14-3.86, I² 84%). In addition, random-effects model indicated a dramatic and direct significant association between GGT and risk of GDM in nonlinear (p < 0.001) and linear (p < 0.001) dose-response analysis. Associations between ALT and AST with risk of GDM were found to be non-significant (OR 1.32, 95% CI 0.91-1.90, I² 65% and OR 0.76, 95% CI 0.52-1.10, I² 16%, respectively).

CONCLUSION

This systematic review and dose-response meta-analysis highlights GGT as a significant and robust predictor of the incidence of GDM in pregnant women.

Association of gamma-glutamyl transferase and alanine aminotransferase with type 2 diabetes mellitus incidence in middle-aged Japanese men: 12-year follow up

AIMS/INTRODUCTION

To prospectively investigate whether simultaneous elevation of gamma-glutamyl transferase (GGT) and alanine aminotransferase (ALT) is associated with the increase of type 2 diabetes mellitus incidence independent of alcohol drinking, body mass index and triglycerides.

METHODS

A total of 2,775 Japanese male workers who had no history of type 2 diabetes mellitus were followed. High GGT and ALT were defined as the top tertiles (GGT cutpoint: 49 IU/L, ALT cutpoint: 28 IU/L). Three groups were created using these dichotomized GGT and ALT cutpoints: both low, either high or both high. Multivariable Cox proportional hazards models were carried out adjusted for potential confounding factors.

RESULTS

A total of 276 type 2 diabetes mellitus cases were identified during 12 years (27,040 person-years) of follow up. Participants with simultaneously elevated GGT and ALT had a significantly higher incidence of type 2 diabetes mellitus, even after adjustment for fasting insulin and fasting blood glucose compared with the group without GGT or ALT elevation. Similar associations were observed in non- or light-to-moderate alcohol drinkers, as well as in participants with normal weight. However, the association was weaker in participants with triglycerides <150 mg/dL. We then evaluated whether the addition of GGT and ALT would improve the prediction of type 2 diabetes mellitus incidence, and found that their inclusion significantly increased the C-statistic, net reclassification improvement and integrated discrimination improvement.

CONCLUSIONS

Simultaneous elevation of GGT and ALT was significantly associated with type 2 diabetes mellitus incidence, independent of potential confounding factors, including alcohol drinking and obesity, although the association might require concomitant elevation of triglycerides. Inclusion of GGT and ALT improved type 2 diabetes mellitus risk prediction.

Gamma-glutamyl transferase as a risk factor for mortality and cardiovascular events in older adults - results from a prospective cohort study in a primary care setting (getABI)

Background: In primary care, the gamma-glutamyl transferase (GGT) activity is used for assessing hepatobiliary dysfunction, but is also known to be associated with the risk of cardiovascular events as well as overall mortality. As this knowledge is mainly based on cohorts with middle-aged participants, we aim to assess these associations in elderly patients in a primary care setting. Patients and methods: 6,880 unselected primary care patients, aged 65 years or older, were enrolled by 344 general practitioners all over Germany (getABI study). During seven years of follow-up, coronary heart disease (CHD) events (myocardial infarction or coronary revascularization), cerebrovascular events (stroke or carotid revascularization) and deaths were recorded. Event rates were calculated and Cox regression analysis with adjustment for age, gender, GGT, classical and other risk factors (e.g. education, homocysteine, C-reactive protein, vitamin D) was performed. Results: 1,243 patients died. 27.8 deaths per 1,000 patient years (0.95 confidence interval [0.95 CI]: 26.2-29.3) occurred in the whole cohort. 605 participants had a CHD event, i.e. 16.1 per 1,000 patient years (0.95 CI: 14.8-17.4). 296 cerebrovascular events were observed, i.e. 7.7 per 1,000 patient years (0.95 CI: 6.9-8.6). Cox regression analysis with adjustment for the above-mentioned risk factors showed a significant impact of baseline elevation of GGT above the 3rd quartile (women > 18 U/L, men > 26 U/L) compared to the rest on mortality (hazard ratio [HR] 1.38, 95% CI 1.22-1.56, p < 0.001) and cerebrovascular events (1.39, 95% CI: 1.08-1.79), p = 0.010), whereas the association with CHD events (HR: 1.16, 95% CI: 0.97-1.39, p = 0.103) showed no significance. Conclusions: In a primary care setting, GGT values have a significant association with overall mortality and cerebrovascular events, but not with CHD events in elderly patients.

Prognostic significance of gamma-glutamyl transferase in patients with metastatic non-small cell lung cancer

BACKGROUND

The prognostic significance of serum gamma-glutamyl transferase (GGT) level at diagnosis in patients with metastatic non-small lung cancer (NSCLC) is not clear. We aimed to assess the relationship between serum GGT level and overall survival (OS) and progression-free survival (PFS) in this patient population.

METHODS

Data of patients with metastatic NSCLC who were admitted to the medical oncology clinic of our hospital during April 2013-December 2017 were retrospectively analyzed. Patients were divided into two groups based on GGT levels, normal and high (as defined by normal reference levels), and then compared.

RESULTS

Significant differences between the high and normal GGT level groups were found regarding female sex, Eastern Cooperative Oncology Group performance score, weight loss at the time of diagnosis, and lactate dehydrogenase level (p < 0.05). The high GGT group had a shorter median OS (11.5 vs. 3.4 months, p < 0.001) and PFS (7.8 vs. 3.0 months, p = 0.001). High GGT level is an independent risk factor for OS (hazard ratio [HR] 2.270; 95% confidence interval [CI], 1.398-3.686; p < 0.001) and PFS (HR 2.489; 95% CI, 1.323-4.684; p = 0.005).

CONCLUSIONS

High serum GGT level is an independent prognostic factor for OS and PFS in metastatic NSCLC patients.

Personality traits and facets linked with self-reported alcohol consumption and biomarkers of liver health

INTRODUCTION

This study examines whether the association between Five Factor Model personality traits and alcohol consumption extends beyond self-report to biomarkers of alcohol consumption.

METHODS

Community-dwelling adults from Sardinia (N = 5380), Italy, completed the revised NEO Personality Inventory and reported on alcohol consumption, while traditional biomarkers of heavy drinking, such as gamma-glutamyl transferase (GGT), were assayed from blood samples.

RESULTS

Associations between self-report measures were modest but consistent with previous findings on the link between personality and alcohol use. For instance, higher scores on the order and self-discipline facets of conscientiousness were associated with reduced risk of heavy alcohol consumption. Personality was also associated with GGT, though effects were small. Personality was unrelated to other biomarkers of liver health.

CONCLUSIONS

This study adds multi-method evidence in support of a link between personality and health behaviors.

Glucose, lipids and gamma-glutamyl transferase measured before prostate cancer diagnosis and secondly diagnosed primary tumours: a prospective study in the Swedish AMORIS cohort

Background

Improvements in detection and treatment of prostate cancer (PCa) translate into more men living with PCa, who are therefore potentially at risk of a secondly diagnosed primary tumour (SDPTs). Little is known about potential biochemical mechanisms linking PCa with the occurrence of SDPTs. The current study aims to investigate serum biomarkers of glucose and lipid metabolism and gamma-glutamyl transferase (GGT) measured prior to PCa diagnosis and their association with the occurrence of SDPTS.

Methods

From the Swedish AMORIS cohort, we selected all men diagnosed with PCa between 1996 and 2011, with at least one of the five biomarkers of interest (glucose, fructosamine, triglycerides, total cholesterol (TC), GGT) measured on average 16 years before PCa diagnosis (n = 10,791). Multivariate Cox proportional hazards models were used to determine hazard ratios (HR) for risk of SDPTs (overall and subtypes) by levels of the five biomarkers. Effect modification of treatment was assessed.

Results

811 SDPTS were diagnosed during a median follow-up time of 5 years. Elevated levels of triglycerides (HR: 1.37, 95%CI: 1.17–1.60), TC (HR: 1.22, 95%CI: 1.04–1.42) and GGT (HR: 1.32, 95%CI: 1.02–1.71) were associated with an increased risk of SDPTs. Risk of SDPTs subtypes varied by biomarkers.

Conclusion

Elevated levels of biomarkers of lipid metabolism and GGT measured prior to PCa diagnosis were associated with an increased risk of SDPTs, suggesting a potential common biochemical background for development of PCa and SDPTs.

A prospective cohort study of the association between bisphenol A exposure and the serum levels of liver enzymes in children

BACKGROUND

Bisphenol A (BPA) is an endocrine disrupter that acts in an estrogen-like manner. Few studies have investigated the association between urinary BPA concentrations and adverse liver function. Additionally, most studies were cross-sectional in nature and included only adults.

OBJECTIVES

We evaluated BPA exposure levels and prospectively explored the association between BPA exposure and liver function in children.

METHODS

Data were retrieved from the ongoing prospective Ewha Birth and Growth Cohort Study. Urinary BPA concentrations were measured in 164 children at 3-5 and 7-9 years of age. At each visit, fasting blood and urine samples were collected, and questionnaires were completed. The associations between the BPA concentrations at these ages and the serum levels of liver enzymes measured at 10-13 years of age were analyzed (n = 113). Multiple regression analysis was performed with adjustment for covariates. We also explored whether the BPA level exhibited dose-response relationships with liver enzyme levels.

RESULTS

The median urinary BPA concentrations were 0.76μg/g creatinine at 3-5 years and 0.61μg/g creatinine at 7-9 years of age. The urinary BPA concentrations at the two ages were correlated significantly (r = 0.23, p < 0.01). The urinary BPA concentrations at 7-9 years, but not that at 3-5 years, was associated significantly with the serum levels of liver enzymes at 10-13 years of age (p < 0.05). Those in the top tertile of urinary BPA concentration had higher levels of liver enzymes than did others. After adjustment for covariates, dose-response relationships of the BPA level with liver enzyme levels were evident at 7-9 years, but not at 3-5 years. Notably, the effect size was larger and the dose-response relationships were more evident in boys than in girls.

CONCLUSIONS

Exposure of children to even low doses of BPA may adversely affect later liver function.

A comparison of gamma-glutamyl transferase and alkaline phosphatase as prognostic markers in patients with coronary heart disease

BACKGROUND AND AIMS

Whether gamma-glutamyl transferase (GGT) or alkaline phosphatase (ALP) is a better prognostic marker in patients with coronary heart disease (CHD) remains unknown. The aim of this study was to compare the prognostic value of GGT and ALP in patients with CHD.

METHODS AND RESULTS

This study included 3768 patients with CHD. The main study outcome was 3-year all-cause mortality. The median values of GGT and ALP were 36.2 U/L and 69.3 U/L. Patients were divided into subgroups according to GGT or ALP activity > or ≤median. Overall, there were 304 deaths: 195 deaths occurred in patients with GGT >median (n = 1882) and 109 deaths occurred in patients with GGT ≤median (n = 1886); Kaplan-Meier [KM] estimates of all-cause mortality were 11.9% and 6.4% (unadjusted hazard ratio [HR] = 1.85, 95% confidence interval [CI], 1.46 to 2.34]; P < 0.001). According to ALP activity, 186 deaths occurred in patients with ALP >median (n = 1883) and 118 deaths occurred in patients with ALP ≤median (n = 1885); KM estimates of all-cause mortality were 11.4% and 7.1% (unadjusted HR = 1.64 [1.30-2.06]; P < 0.001). After adjustment, GGT (adjusted HR = 1.32 [1.11-1.58]; P = 0.002) but not ALP (adjusted HR = 1.20 [1.00-1.43]; P = 0.051, with both HR calculated per 1 unit increment in logarithmic GGT or ALP scale) remained significantly associated with the risk for mortality. The C statistic of the mortality model with GGT was greater than the C statistic of the model with ALP (0.831 [0.802-0.859] vs. 0.826 [0.793-0.855]; P < 0.001).

CONCLUSIONS

In patients with CHD, GGT was a stronger correlate of all-cause mortality than ALP.

Apoplastic gamma-glutamyl transferase activity encoded by GGT1 and GGT2 is important for vegetative and generative development

Gamma-glutamyl transferase (GGT; EC 2.3.2.2) is the only enzyme capable of degrading glutathione (GSH) in extra-cytosolic spaces. In plant cells, the GGT1 and GGT2 isoforms are located in the apoplast, bound respectively to the cell wall and the plasma membrane. GGT1 is expressed throughout plants, mainly in the leaves and vascular system, while GGT2 is more specifically expressed in seeds and trichomes, and weakly in roots. Their role in plant physiology remains to be clarified, however. Obtaining the ggt1/ggt2 double mutant can offer more clues than the corresponding single mutants, and to prevent any compensatory expression between the two isoforms. In this work, ggt1/ggt2 RNAi (RNA interference) lines were generated and characterized in the tissues where both isoforms are expressed. The seed yield was lower in the ggt1/ggt2 RNAi plants due to the siliques being fewer in number and shorter in length, with no changes in thiols and sulfur compounds. Proline accumulation and delayed seed germination were seen in one line. There were also fewer trichomes (which contain high levels of GSH) in the RNAi lines than in the wild type, and the root elongation rate was slower. In conclusion, apoplastic GGT silencing induces a decrease in the number of organs with a high GSH demand (seeds and trichomes) as a result of resource reallocation to preserve integrity and composition.

Elevated fasting glucose and albuminuria may be a marker for all-cause mortality in Indigenous adults in North Queensland - a follow up study, 1998-2006

AIMS

To document risk factors of all-cause mortality in a cohort of indigenous Australians from 23 communities of North Queensland during 1998-2006.

METHODS

Among 2787 indigenous adults, baseline weight, waist circumference, blood pressure, fasting glucose, lipids, gamma-glutamyl transferase, urine albumin creatinine ratio, smoking, alcohol intake and physical activity were measured in 1998-2000. Deaths were ascertained from State Registry of Deaths, hospitalization and clinical records till 2006. Mortality risk factors were assessed using a Cox proportional-hazards model.

RESULTS

The standardized all-cause mortality rate was 23.2/1000 person-years (95% CI 20.3-26.3/1000 pys). After adjusting for age, sex, and ethnicity, baseline plasm fasting glucose >=5.5mmol/L was associated with a 50% increased risk of death (HR 1.5, 95% CI 1.2-2.0). Albuminuria was associated with all-cause mortality with a hazards ratio of 1.4 for microalbuminuria (95% CI 1.0-1.9) and 2.6 (95% CI 1.8-3.7) for macroalbuminuria. Gamma-glutamyl transferase >=50IU was associated with an increased risk of all-cause mortality by 40% (95% CI 1.04-1.8).

CONCLUSIONS

Fasting glycaemia, albuminuria, and gamma-glutamyl transferase, may be a marker for all-cause mortality within this cohort.

Serum Gamma-glutamyl Transferase Levels Predict Functional Outcomes after Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

We aim to explore the potential association between serum gamma-glutamyl transferase levels and functional outcome after aneurysmal subarachnoid hemorrhage in a Chinese population.

METHODS

A total of 386 aneurysmal subarachnoid hemorrhage patients were included in the study from September 2007 to February 2015. Baseline serum gamma-glutamyl transferase levels and 6-month follow-up functional outcomes were determined. A poor outcome was defined as a modified ranking scale score of ⋝ 3. The multivariable logistic model was used to analyze the relationship between serum gamma-glutamyl transferase and clinical outcomes after aneurysmal subarachnoid hemorrhage.

RESULTS

The adjusted poor outcome rates of patients with gamma-glutamyl transferase levels of < 30 U/L, 30-50 U/L and ⋝ 50 U/L were 16.7%, 19.6%, and 34.4%, respectively (P < 0.01). The age-sex and multivariable adjusted odds ratios (95% confidence intervals) of poor prognosis comparing the top group (⋝ 50 U/L) with the lowest group (< 30 U/L) were 5.76 (2.74-12.13), 6.64 (2.05-21.52), and 6.36 (1.92-21.02). A significant linear trend existed between gamma-glutamyl transferase level and aneurysmal subarachnoid hemorrhage prognosis. This association was also observed among nondrinkers.

CONCLUSION

Patients with higher gamma-glutamyl transferase levels were more likely to have a poor prognosis. Serum gamma-glutamyl transferase can be considered to be an independent predictor of functional outcomes after aneurysmal subarachnoid hemorrhage.

Ductular reaction, cytokeratin 7 positivity, and gamma-glutamyl transferase in multistage hepatocarcinogenesis in rats

Hepatocellular carcinoma (HCC) is the most common primary malignancy of the liver and is characterized by multistage formation. The presence of ductular reaction, cytokeratin 7 positivity (PCK7), and increased levels of gamma glutamyltransferase (γGT) has been observed during liver carcinogenesis and contribute to tumor progression. Our goal was to evaluate the ductular reaction in multistage carcinogenesis and to correlate PCK7 and γGT levels with tumor incidence, histological characteristics, liver DNA damage index, and the expression of oxidative stress proteins. HCC was induced in 24 male Wistar rats weighing 145-150 g by chronic and intermittent exposure to 50 or 100 mg/kg diethylnitrosamine (DEN). Six control animals received only vehicle. Blood was collected to determine hepatic enzyme levels. Animals were divided into three groups: control (CO), precancerous lesions (PL), and advanced HCC. Liver samples were obtained for immunohistochemical analyses and the measurement of protein expression. Statistical analyses included Tukey's test and Pearson's correlation analyses. We observed an extensive ductular reaction in advanced HCC and a strong correlation between PCK7 and levels of γGT and the poor prognosis and aggressiveness of HCC. The extent of PCK7 and high γGT levels were associated with overexpression of inducible nitric oxide synthase (iNOS) and heat shock factor protein 1 (HSF-1). However, PCK7 and γGT levels were negatively correlated with protein expression of nuclear factor erythroid 2-related factor 2 (NRF2) and inducible heat shock protein 70 (iHSP70). These findings suggest that ductular reaction is involved in the progression of multistage hepatocarcinogenesis.

Gamma-glutamyl transferase predicts recurrences of atrial fibrillation after catheter ablation

BACKGROUND

Catheter ablation is a popular therapy of atrial fibrillation (AF). Gamma-glutamyl transferase (GGT) is known as a marker of oxidative stress. The objective of this study was to ascertain the relationship between levels of GGT and recurrence of AF after catheter ablation.

METHODS

A total of 102 paroxysmal AF patients who underwent cryoballoon catheter ablation were enrolled. Serum samples were obtained to evaluate GGT levels before catheter ablation. Cox regression analysis was used to estimate the predictors of AF recurrence.

RESULTS

Mean age of the cohort was 49.9 ± 11.7 and 63% of the patients were male. After a mean follow-up of 20 months, 19 (23%) patients had AF recurrences. The baseline GGT levels were significantly higher in patients who had AF recurrence [27 U/L (17-36) vs 18 U/L (13-22), P = 0.002]. The optimal cut-off value of GGT to predict AF recurrence was 23.5 U/L according to receiver operating characteristic curve analysis (area under the curve 0.72, P = 0.002). In the multivariable Cox regression analysis, baseline GGT > 23.5 was the only independent predictor of AF recurrence (hazard ratio (HR) 4.47, 95% confidence interval [1.66-12.09], P = 0.003).

CONCLUSIONS

Our results indicate that elevated GGT is associated with AF recurrence. A simple measurement of GGT may help us to identify high-risk patients undergoing catheter ablation for AF.

Prognostic value of gamma-glutamyl transferase in patients with diabetes mellitus and coronary artery disease

OBJECTIVES

The aim of the study was to investigate the association between gamma-glutamyl transferase (GGT) activity and mortality in patients with diabetes mellitus and coronary artery disease (CAD).

DESIGN AND METHODS

The study included 1448 patients with diabetes and angiography-proven CAD who underwent percutaneous coronary intervention (PCI). Baseline GGT measurements were available in all patients. The primary outcome was 3-year mortality.

RESULTS

Patients were divided into 3 groups: a group consisting of patients with a GGT activity in the 1st tertile (GGT≤29.4U/L; n=487), a group consisting of patients with a GGT activity in the 2nd tertile (GGT>29.4-52.5U/L; n=479) and a group consisting of patients with GGT in the 3rd tertile (GGT>52.5U/L; n=482). Overall, there were 179 deaths: 46 (11.9%), 49 (12.1%) and 84 deaths (21.4%) among patients of the 1st, 2nd and 3rd GGT tertiles, respectively (adjusted hazard ratio [HR]=1.25, 95% confidence interval [CI] 1.05-1.49, P=0.011). Cardiac death occurred in 101 patients: 22 (5.8%), 30 (7.2%) and 49 deaths (12.9%) among patients of the 1st, 2nd and 3rd GGT tertiles, respectively (adjusted HR=1.23 [0.96-1.58], P=0.104, with risk estimates calculated per standard deviation increase in the logarithmic scale of GGT). GGT improved the risk prediction of models of all-cause (P=0.020) but not cardiac (P=0.135) mortality (P values show the difference in C-statistics between the models without and with GGT).

CONCLUSION

In patients with diabetes and CAD treated with PCI, elevated GGT was independently associated with the risk of 3-year all-cause mortality.

Elevated gamma-glutamyl transferase is associated with subclinical inflammation independent of cardiometabolic risk factors in an asymptomatic population: a cross-sectional study

Background

Serum Gamma-Glutamyl Transferase (GGT), a marker of oxidative stress, has been suggested to be independently associated with cardiovascular disease (CVD) events. We examined the association of serum GGT levels with the burden of subclinical inflammation across a spectrum of metabolic conditions.

Methods

We evaluated 5,446 asymptomatic subjects (43 ± 10 years, 78 % males) who had an employer-sponsored physical between 2008 and 2010. Highly sensitivity C-reactive protein (hsCRP) was measured as a marker of underlying systemic inflammation. A linear regression of GGT quartiles with log transformed hsCRP and a multivariate logistic regression of GGT quartiles with elevated hsCRP (≥3 mg/L) were performed.

Results

Median GGT was 31 IU/l (IQR: 22–45 IU/l), 1025 (19 %) had hsCRP ≥ 3 mg/L. The median hsCRP increased with GGT quartiles (Q1: 0.9 mg/L, Q2: 1.1 mg/L, Q3: 1.4 mg/L, Q4: 1.6 mg/L, p < 0.001). Linear regression models showed GGT in the fourth quartile was associated with 0.45 mg/L (95 % CI 0.35, 0.54, p < 0.001) increase in log transformed hsCRP adjusting for risk factors. The Odds Ratio (OR) for an elevated hsCRP (≥3 mg/L) also increased with higher GGT quartiles; GGT Q2 1.44 (95 % CI 1.12, 1.85), GGT Q3 1.89 (95 % CI 1.45, 2.46), GGT Q4 2.22 (95 % CI 1.67, 2.95), compared to GGT Q1. The strength of association increased in the presence of and combination of metabolic conditions.

Conclusion

In our cohort of asymptomatic individuals a higher serum GGT level was independently associated with increased burden of subclinical inflammation across metabolic states. These findings may explain GGT association with increased CVD risk.

Elevation of gamma-glutamyl transferase in adult: Should we think about progressive familiar intrahepatic cholestasis?

BACKGROUND

There are three types of progressive familial intrahepatic cholestasis (PFIC). Type 3 is characterized by elevated gamma-glutamyl transferase (γ-GT) and it can be diagnosed in adolescence/adulthood. The genetic defect of PFIC 3 appears to explain the pathogenesis of intrahepatic cholestasis of pregnancy (ICP).

AIMS

Draw attention to this rare disease, especially in adulthood, and clarify the association between ICP and PFIC 3.

RESULTS

We describe a series of cases from a Portuguese northern family with two brothers presenting chronic cholestasis since adolescence. Brother 1: since 15-years-old with pruritus and elevated γ-GT ∼6x. Brother 2: pre-term, due to severe maternal pruritus and jaundice, since 13-years-old with pruritus, jaundice and ∼8x γ-GT elevation. Common causes of cholestasis were excluded and liver histologies were nonspecific. Research for mutation on ABCB4 gene showed mutations in both alleles.

CONCLUSION

Disease and mechanisms that determine cholestasis are complex and their understanding may provide new therapeutics.

Leaf apoplastic proteome composition in UV-B treated Arabidopsis thaliana mutants impaired in extracellular glutathione degradation

In plants, environmental perturbations often result in oxidative reactions in the apoplastic space, which are counteracted for by enzymatic and non-enzymatic antioxidative systems, including ascorbate and glutathione. However, the occurrence of the latter and its exact role in the extracellular space are not well documented. In Arabidopsis thaliana, the gamma-glutamyl transferase isoform GGT1 bound to the cell wall takes part in the so-called gamma-glutamyl cycle for extracellular glutathione degradation and recovery, and may be implicated in redox sensing and balance. In this work, oxidative conditions were imposed with UV-B radiation and studied in redox altered ggt1 mutants. Elevated UV-B has detrimental effects on plant metabolism, plasma membranes representing a major target for ROS generated by this harmful radiation. The response of ggt1 knockout Arabidopsis leaves to UV-B radiation was assessed by investigating changes in apoplastic protein composition. We then compared the expression changes resulting from the mutation and from the UV-B treatment. Rearrangements occurring in apoplastic protein composition suggest the involvement of hydrogen peroxide, which may ultimately act as a signal. Other important changes related to hormonal effects, cell wall remodeling, and redox activities are also reported. We argue that oxidative stress conditions imposed by UV-B and by disruption of the gamma-glutamyl cycle result in similar stress-induced responses, to some degree at least. Data shown here are associated with the article from Trentin et al. (2015) [1]; protein data have been deposited to the PRIDE database (Vizcaíno et al., 2014) [2] with identifier PXD001807.

Gamma-glutamyl transferase and prognosis in patients with coronary artery disease

BACKGROUND

The association between gamma-glutamyl transferase (GGT) activity and outcome of patients with coronary artery disease (CAD) remains poorly investigated.

METHODS

The study included 5501 patients with CAD treated with percutaneous coronary intervention and GGT measurements available. The primary outcome was 3-year mortality.

RESULTS

GGT activity tertiles were: 1st tertile (GGT<28.10U/L; n=1866), 2nd tertile (GGT≥28.10U/L to49.50U/L; n=1804) and 3rd tertile (GG>49.50U/L; n=1831). There were 110 deaths in the 1st, 111 deaths in the 2nd and 216 deaths in the 3rd GGT tertile (mortality estimates, 7.1%, 7.2% and 13.9%; P<0.001). GGT was independently associated with the increased risk of 3-year all-cause (adjusted hazard ratio [HR]=1.30, 95% confidence interval [CI] 1.18 to 1.44, P<0.001), cardiac (HR=1.21 [1.06-1.39], P=0.005) and non-cardiac (HR=1.42 [1.23-1.63], P<0.001) mortality (all risk estimates calculated per standard deviation increase in the log GGT activity). GGT improved prediction of all-cause (P<0.001) and non-cardiac mortality (P<0.001) but not cardiac mortality (P=0.155).

CONCLUSIONS

In patients with CAD, elevated GGT activity is associated with increased risk of 3-year all-cause, cardiac and non-cardiac mortality. GGT provided incremental prognostic information on top of cardiovascular and metabolic risk factors for prediction of all-cause and non-cardiac mortality but not cardiac mortality.

Association of serum gamma-glutamyl transferase with treatment outcome in chronic hepatitis B patients

AIM: To investigate the association of serum gamma-glutamyl transferase (GGT) levels with chronic hepatitis B infection and hepatitis B e antigen (HBeAg) seroconversion.

METHODS: A retrospective study was performed on clinical data collected from patients who had been positive for hepatitis B surface antigen for > 6 mo and who were antiviral-treatment naïve (n = 215) attending the Hepatitis Clinic at Nanjing Drum Tower Hospital between August 2010 and December 2013. Healthy individuals without liver disease (n = 83) were included as controls. Patients were categorized into four groups based on disease status as recommended by the European Association for the Study of the Liver: immune tolerance (IT; n = 47), HBeAg-positive hepatitis (EPH; n = 93), HBeAg-negative hepatitis (ENH; n = 20), and inactive carrier (IC; n = 55). Prediction of complete response (CR) based on serum GGT was also examined in EPH patients (n = 33) treated for 48 wk with nucleos(t)ide analogue (NA) therapy, including lamivudine plus adefovir combination therapy (n = 20) or entecavir monotherapy (n = 13). CR was defined as a serum hepatitis B virus DNA level < 500 copies/mL and HBeAg seroconversion by 48 wk of treatment.

RESULTS: Serum GGT levels were significantly increased in EPH and ENH patients relative to the IT, IC, and healthy control groups (P < 0.01 for all). However, no significant difference in serum GGT levels was found between the EPH and ENH groups. Baseline serum GGT levels were significantly higher in patients who achieved CR (7/33; 21.2%) compared to patients in the non-CR group (26/33; 78.8%; P = 0.011). In addition, the decline in serum GGT was greater in CR patients compared to non-CR patients after 24 wk and 48 wk of treatment (P = 0.012 and P = 0.008, respectively). The receiver operating characteristic curve yielded a sensitivity of 85.71% and a specificity of 61.54% at a threshold value of 0.89 times the upper limit of normal for baseline serum GGT in the prediction of CR following NA therapy.

CONCLUSION: Serum GGT is significantly elevated in EPH and ENH patients and is a potential biomarker for the prediction of HBeAg seroconversion following NA therapy.

Increased liver markers are associated with higher risk of type 2 diabetes

AIM: To investigate the association between liver markers and the risk of type 2 diabetes (T2DM) and impaired fasting glucose (IFG).

METHODS: A total of 8863 participants (3408 men and 5455 women) over 30 years of age were analyzed from the fifth Korean National Health and Nutrition Examination Survey (2010-2011). The associations of serum liver markers such as aspartate aminotransferase (AST), alanine aminotransferase (ALT), AST/ALT, and gamma-glutamyltransferase (GGT) with T2DM and IFG were analyzed using logistic regression models. Participants were divided into sex-specific quartiles on the basis of liver markers.

RESULTS: The prevalence of T2DM and IFG were 11.3% and 18.3%. Increasing quartiles of ALT and GGT were positively and AST/ALT were negatively correlated with T2DM and IFG. Analysis of the liver marker combinations showed that if any two or more markers were in the highest risk quartile, the risks of both T2DM and IFG increased significantly. The risk was greatest when the highest ALT and GGT and lowest AST/ALT quartile were combined, with the risk of T2DM at 3.21 (95%CI: 1.829-5.622, P < 0.001) in men and 4.60 (95%CI: 3.217-6.582, P < 0.001) in women. Men and women with the highest AST and ALT and lowest AST/ALT quartile had a 1.99 and 2.40 times increased risk of IFG.

CONCLUSION: Higher levels of GGT and ALT and lower AST/ALT within the physiological range are independent, additive risk factors of T2DM and IFG.

Gamma-glutamyl transpeptidase: redox regulation and drug resistance

The expression of gamma-glutamyl transpeptidase (GGT) is essential to maintaining cysteine levels in the body. GGT is a cell surface enzyme that hydrolyzes the gamma-glutamyl bond of extracellular reduced and oxidized glutathione, initiating their cleavage into glutamate, cysteine (cystine), and glycine. GGT is normally expressed on the apical surface of ducts and glands, salvaging the amino acids from glutathione in the ductal fluids. GGT in tumors is expressed over the entire cell membrane and provides tumors with access to additional cysteine and cystine from reduced and oxidized glutathione in the blood and interstitial fluid. Cysteine is rate-limiting for glutathione synthesis in cells under oxidative stress. The induction of GGT is observed in tumors with elevated levels of intracellular glutathione. Studies in models of hepatocarcinogenesis show that GGT expression in foci of preneoplastic hepatocytes provides a selective advantage to the cells during tumor promotion with agents that deplete intracellular glutathione. Similarly, expression of GGT in tumors enables cells to maintain elevated levels of intracellular glutathione and to rapidly replenish glutathione during treatment with prooxidant anticancer therapy. In the clinic, the expression of GGT in tumors is correlated with drug resistance. The inhibitors of GGT block GGT-positive tumors from accessing the cysteine in extracellular glutathione. They also inhibit GGT activity in the kidney, which results in the excretion of GSH in the urine and a rapid decrease in blood cysteine levels, leading to depletion of intracellular GSH in both GGT-positive and GGT-negative tumors. GGT inhibitors are being developed for clinical use to sensitize tumors to chemotherapy.

Relationship between Serum Gamma-glutamyl Transferase Levels with Ascending Aortic Dilatation

OBJECTIVE

Increased serum gamma-glutamyl transferase levels (GGT) have been shown to directly promote oxidative stress. Previous studies have shown the relationship between the dilatation of the ascending aorta and oxidative stress. This study was designed to examine the relationship between serum GGT concentrations with dilatation of the ascending aorta.

MATERIALS AND METHODS

Ninety patients with ascending aortic dilatation and 90 age-sex-matched patients without aortic dilatation were included in the study. The patients were evaluated by a complete transthoracic echocardiographic examination including measurement of the aortic dimensions, where a diameter of 3.7 cm and above was accepted as ascending aortic dilatation. Serum GGT concentration was measured in all patients.

RESULTS

In the group with aortic dilatation, HT frequency, serum uric acid, hs-CRP and GGT levels, the LV mass index, and the left atrial volume index were found to be higher than the control group. The logistic regression analysis showed that only HT frequency (OR:1.23, 95% CI 1.11-1.35, p value: 0.02), the LA volume index (OR: 1.34, 95% CI 1.21±1.4, p:0.005) and serum GGT levels (OR: 1.12, 95% CI 1.01±1.20, p:0.03) were found to be independent predictors. There was a significant correlation between serum GGT levels and ascending aortic diameter (r: 0.268, p<0.001). In the ROC curve analysis, AUC was 0.659 (0.580±0.738) for a 23.5 serum GGT cut-off value (64% sensitivity and 53% specificity).

CONCLUSION

We found that serum GGT concentration was significantly associated with ascending aortic dilatation. Large epidemiological studies are required to correlate the findings from this study with clinical outcome.

Serum gamma-glutamyl transferase is associated with the elevated uric acid levels in normotensive Chinese adults

BACKGROUND

Although both serum gamma-glutamyltransferase (GGT) and uric acid are correlated with hypertension, studies on the association between serum GGT and uric acid in normotensive individuals are rare. In this study, we tried to reveal this relationship in normotensive Chinese adults.

METHODS

Four hundred seven normotensive adults were recruited. The subjects were divided into 3 subgroups according to serum GGT tertiles. Anthropometric parameters as well as systolic blood pressure (SBP), diastolic blood pressure (DBP), uric acid, GGT, alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood glucose, blood lipids, and fasting insulin were measured. Insulin resistance was assessed using HOMA-IR index.

RESULTS

Uric acid was increased in parallel with increasing serum GGT (P<0.001). After correction for age, sex, smoking and alcohol consumption, serum GGT was positively associated with uric acid (r=0.42, P<0.001), SBP (r=0.22, P<0.001), and DBP (r=0.19, P<0.001). When compared with lowest GGT tertile, the odds ratio of the middle tertile for the increased serum uric acid was 3.43 (95% CI, 1.39-8.47) and 7.29 (95% CI, 1.57-33.82) for the highest tertile after adjustment for age, sex, BMI, smoking, alcohol consumption, SBP, DBP, creatinine and HOMA-IR.

CONCLUSIONS

Serum GGT is strongly associated with the increased uric acid concentrations in normotensive Chinese adults.

Relationships of elevated levels of serum hepatic enzymes and alcohol intake with arterial stiffness in men

OBJECTIVE

The present study aimed to evaluate the relationships between elevated serum levels of hepatic enzymes and arterial stiffness and to investigate whether alcohol intake had a modifying effect on these relationships in Japanese men.

METHODS

A total of 647 eligible men aged 35-69 years who underwent measurement of brachial-ankle pulse wave velocity (baPWV) as an index of arterial stiffness were evaluated. Information on their lifestyle characteristics were obtained from a structured self-administered questionnaire. Serum biochemical factors, including alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT), were determined. The serum ALT and GGT levels were divided into tertiles, and their associations with baPWV values were evaluated using general linear models adjusted for potential confounding factors. The interaction effects between serum hepatic enzymes and alcohol intake on baPWV were further evaluated.

RESULTS

Elevated serum ALT and GGT levels were proportionally associated with increased baPWV after adjusting for the multivariable covariates (P values for trend, 0.004 and 0.003, respectively). Further analyses revealed that the proportional associations between serum levels of hepatic enzymes and baPWV were striking in the subjects without alcohol intake but not in those with alcohol intake. The interaction effect between serum GGT level and alcohol intake on baPWV was significant (P for interaction, 0.042).

CONCLUSION

These results demonstrate that elevated serum ALT and GGT levels are associated with increased arterial stiffness, independent of the classical atherosclerotic risk factors in Japanese men, and that the association of elevated serum GGT level with arterial stiffness differs according to alcohol intake.

Gamma-glutamyl transferase and risk of type II diabetes: an updated systematic review and dose-response meta-analysis

PURPOSE

We assessed the nature of the dose-response relationship between gamma-glutamyl transferase (GGT) levels and risk of incident type II diabetes mellitus (T2DM) in the general population.

METHODS

Systematic review and dose-response meta-analysis of published prospective studies. Relevant studies were identified in a literature search of MEDLINE, EMBASE, and Web of Science databases up to June 2014. We examined a potential nonlinear relationship using restricted cubic splines.

RESULTS

Of the 300 titles reviewed, we included 24 cohort studies with data on 177,307 participants and 11,155 T2DM cases. In pooled analysis of 16 studies with relevant data, there was evidence of a nonlinear association between GGT and T2DM risk in both males (P for nonlinearity = .02) and females (P for nonlinearity = .0005). In a comparison of extreme thirds of baseline levels of GGT, relative risk for T2DM in pooled analysis of all 24 studies was 1.34 (95% confidence interval, 1.27-1.42). There was heterogeneity among the studies (P < .001), which was to a large part explained by blood sample used, study size, degree of confounder adjustment, and quality of studies.

CONCLUSIONS

Circulating level of GGT contributes to an increased risk of T2DM in the general population in a nonlinear dose-response pattern.

Uric acid and gamma-glutamyl transferase activity are associated with left ventricular remodeling indices in patients with chronic heart failure

INTRODUCTION AND OBJECTIVES

Uric acid and gamma-glutamyl transferase are prognostic indicators in chronic heart failure. Nevertheless, the mechanism underlying the association between uric acid, gamma-glutamyl transferase, and chronic heart failure progression and prognosis remains largely unknown.

METHODS

The association of uric acid and gamma-glutamyl transferase with flow-mediated dilation and echocardiographic indices of cardiac remodeling was addressed in 120 patients with chronic ischemic heart failure. To determine the independent contribution of uric acid and gamma-glutamyl transferase to the flow-mediated dilation and echocardiographic indices of remodeling, a series of multiple linear regression models, based on traditional and nontraditional risk factors impacting upon these parameters, were constructed.

RESULTS

Uric acid, but not gamma-glutamyl transferase, was an independent predictor of flow-mediated dilation. Uric acid was associated with all the echocardiographic indices of left ventricular dysfunction tested in 3 multiple-regression models. Uric acid correlated with left ventricular end-systolic diameter, left ventricular end-diastolic diameter, left ventricular end-systolic volume, and left ventricular end-diastolic volume (r = 0.337; r = 0.340; r = 0.321; r = 0.294; P = .001, respectively). Gamma-glutamyl transferase was an independent predictor of left ventricular end-systolic volume and left ventricular end-diastolic volume, after adjustment for all variables. Gamma-glutamyl transferase correlated with left ventricular end-systolic diameter, left ventricular end-diastolic diameter, left ventricular end-systolic volume, and left ventricular end-diastolic volume (r = 0.238, P = .009; r = 0.219, P = .016; r = 0.359, P < .001; r = 0.369, P = .001, respectively).

CONCLUSIONS

Serum uric acid and gamma-glutamyl transferase levels are associated with left ventricular remodeling in patients with chronic ischemic heart failure.