Serum gamma-glutamyltransferase within its normal range predicts a chronic elevation of alanine aminotransferase: A four year follow-up study

Background: Previous epidemiological and experimental studies support the concept that serum gamma-glutamyltransferase (GGT) activity within its normal range is related to oxidative stress. Since oxidative stress plays a crucial role in the pathogenesis of various liver diseases, serum GGT may predict development of liver damage.

Methods: A total of 6,523 healthy male workers with normal alanine aminotransferase (ALT, <35?U/l) in a steel manufacturing company were followed for four years. Liver damage was defined as a chronic elevation of serum ALT (both 2001 and 2002).

Results: After adjusting for age, body mass index, alcohol consumption, cigarette smoking, exercise, and baseline value of ALT, in comparison with the group whose GGT level was <10?U/l, the adjusted relative risks for elevated ALT level among those with GGT levels 10–19, 20–29, 30–39, and over 40?U/l was 1.0, 2.5, 4.7, 7.4, and 12.0, respectively (P for trend <0.01). More importantly, this association was similarly observed even among non-drinkers; the corresponding relative risks were 1.0, 1.8, 3.8, 5.6, and 6.2 (P for trend <0.01). However baseline ALT did not predict abnormal GGT level four years later.

Conclusion: Serum GGT levels within normal range predict incidence of chronic elevation of ALT. Oxidative stress might explain this relationship.     

Is serum gamma-glutamyltransferase inversely associated with serum antioxidants as a marker of oxidative stress?

A series of studies in black and white women and men have suggested that serum gamma-glutamyltransferase (GGT) within its normal range might be an early marker of oxidative stress. If serum GGT is a marker of oxidative stress, it might have important implications both clinically and epidemiologically because measurement of serum GGT is easy, reliable, and not expensive. We examined the cross-sectional association between deciles of serum GGT and concentrations of serum antioxidants among 9083 adult participants in the third U.S. National Health and Nutrition Examination Survey. After adjustment for race, sex, age, and total cholesterol, serum concentration of GGT across all deciles was inversely associated with serum concentrations of alpha-carotene, beta-carotene, beta-cryptoxanthin, zeaxanthin/lutein, lycopene, and vitamin C (p for trend <.01, respectively). Vitamin E was not associated with serum GGT. All these associations were not materially different after additional adjustment for total energy intake, body mass index, smoking status, smoking amount, alcohol intake, and exercise. These associations were similarly observed among most subgroups. In conclusion, the current and previous studies strongly suggest that serum GGT level within its normal range may be an early marker of oxidative stress.     

Is serum gamma glutamyltransferase a marker of oxidative stress?

The primary role of cellular gamma glutamyltransferase (GGT) is to metabolize extracellular reduced glutathione (GSH), allowing for precursor amino acids to be assimilated and reutilized for intracellular GSH synthesis. Paradoxically, recent experimental studies indicate that cellular GGT may also be involved in the generation of reactive oxygen species in the presence of iron or other transition metals. Although the relationship between cellular GGT and serum GGT is not known and serum GGT activity has been commonly used as a marker for excessive alcohol consumption or liver diseases, our series of epidemiological studies consistently suggest that serum GGT within its normal range might be an early and sensitive enzyme related to oxidative stress. For example, serum and dietary antioxidant vitamins had inverse, dose-response relations to serum GGT level within its normal range, whereas dietary heme iron was positively related to serum GGT level. More importantly, serum GGT level within its normal range positively predicted F2-isoprostanes, an oxidative damage product of arachidonic acid, and fibrinogen and C-reactive protein, markers of inflammation, which were measured 5 or 15 years later, in dose-response manners. These findings suggest that strong associations of serum GGT with many cardiovascular risk factors and/or events might be explained by a mechanism related to oxidative stress. Even though studies on serum and/or cellular GGT is at a beginning stage, our epidemiological findings suggest that serum GGT might be useful in studying oxidative stress-related issues in both epidemiological and clinical settings.     

Prognostic Relevance of Pretherapeutic Gamma-Glutamyltransferase in Patients with Primary Metastatic Breast Cancer

Background

Gamma-glutamyltransferase (GGT) is a known marker for apoptotic balance and cell detoxification. Recently, an association of baseline GGT levels and breast cancer incidence, tumor progression and chemotherapy resistance was shown. The purpose of this study was to evaluate the association of pre-therapeutic GGT levels, clinical-pathological parameters and survival in patients with primary metastatic breast cancer (PMBC).

Methods

In this multicenter analysis, pre-therapeutic GGT levels and clinical-pathological parameters of 114 patients diagnosed with PMBC between 1996 and 2012 were evaluated. The association between GGT levels and clinical-pathological parameters were analysed. Patients were stratified into four GGT risk-groups (GGT < 18.00 U/L: normal low, 18.00 to 35.99 U/L: normal high, 36.00 to 71.99 U/L: elevated and ≥ 72.00 U/L: highly elevated) and survival analyses were performed.

Findings

Patients in the high risk GGT group had a poorer overall survival, when compared to the low risk group with five-year overall survival rates of 39.5% and 53.7% (p = 0.04), respectively. Patients with larger breast tumors had a trend towards higher GGT levels (p = 0.053). Pre-therapeutic GGT levels were not associated with indicators of aggressive tumor biology such as HER2-status, triple negative histology, or poorly differentiated cancers.

Conclusion

Pre-therapeutic GGT serum level might serve as a novel prognostic factor for overall-survival in patients with PMBC.     

Effect of Vitamin E on Serum Aminotransferase and Thioredoxin Levels in Patients with Viral Hepatitis C

Objectives: Oxidative stress induces cellular responses such as cell death, gene activation and cell proliferation, in the liver. Vitamin E (Vit. E) has been found to protect the liver against oxidative stress in animal experiments. Thioredoxin (TRX) is a stress inducible, multifunctional protein, secreted during oxidative stress. This study evaluated effects of Vit. E on serum TRX and aminotransferase levels in hepatitis C virus (HCV) patients, partly non-responsive to initial interferon (IFN), with higher than average level of serum alanine aminotransferase (ALT) after receiving anti-inflammatory drug treatment. Methods: Seventeen HCV patients (male=3; female=14) of age 62±7.65 years receiving anti-inflammatory drug therapy, at least 6 months prior to Vit. E administration, were given d-α´-tocopherol 500?mg/day, orally, for a period of 3 months. ALT, aspartate aminotransferase (AST), TRX and Vit. E were measured at 0, 1, 2 and 3 months and 1 month after end of treatment. As controls, the same patients biochemical data, 3 months from the start of therapy were used. Patients were divided into three categories: total patients “T”, low ALT group “L” (ALT<70?IU/l) and high ALT group “H”(ALT>70?IU/l), respectively.Results: The ALT level was lowered, significantly in group H, in the 1st, 2nd, 3rd and 1-month post therapy, compared to the initial value. But group L showed little or no change in ALT. Post Vit. E therapy, in groups T and H, the TRX level was elevated but remained below initial levels, whereas in group L, TRX level remained significantly lower than the pretreatment value. Groups T and L, showed significant reduction (p<0.05) in serum TRX levels in the 2nd and 3rd month. Group H showed a tendency towards TRX reduction, but not significantly. Serum Vit. E levels increased significantly (p<0.0001) from the 1st to 3rd month in all three T, H and L groups. Conclusion: Oxidative stress induced liver damage is reduced by Vit. E in patients with viral hepatitis C, particularly those with initial ALT levels >70?IU/l. Vit. E treatment causes reduction of oxidative stress markers as TRX and ALT in sera. Therefore, Vit. E can act as a supportive therapy to combat liver damage caused by oxidative stress, in such patients with continuously high levels of ALT even after anti-viral and anti-inflammatory drug therapy.     

Effect of vitamin E on serum aminotransferase and thioredoxin levels in patients with viral hepatitis C

OBJECTIVES: Oxidative stress induces cellular responses such as cell death, gene activation and cell proliferation, in the liver. Vitamin E (Vit. E) has been found to protect the liver against oxidative stress in animal experiments. Thioredoxin (TRX) is a stress inducible, multifunctional protein, secreted during oxidative stress. This study evaluated effects of Vit. E on serum TRX and aminotransferase levels in hepatitis C virus (HCV) patients, partly non-responsive to initial interferon (IFN), with higher than average level of serum alanine aminotransferase (ALT) after receiving anti-inflammatory drug treatment. METHODS: Seventeen HCV patients (male = 3; female = 14) of age 62 +/- 7.65 years receiving anti-inflammatory drug therapy, at least 6 months prior to Vit. E administration, were given d-alpha-tocopherol 500 mg/day, orally, for a period of 3 months. ALT, aspartate aminotransferase (AST), TRX and Vit. E were measured at 0, 1, 2 and 3 months and 1 month after end of treatment. As controls, the same patients biochemical data, 3 months from the start of therapy were used. Patients were divided into three categories: total patients "T", low ALT group "L" (ALT < 70 IU/l) and high ALT group "H" (ALT > 70 IU/l), respectively. RESULTS: The ALT level was lowered, significantly in group H, in the 1st, 2nd, 3rd and 1-month post therapy, compared to the initial value. But group L showed little or no change in ALT. Post Vit. E therapy, in groups T and H, the TRX level was elevated but remained below initial levels, whereas in group L, TRX level remained significantly lower than the pretreatment value. Groups T and L, showed significant reduction (p < 0.05) in serum TRX levels in the 2nd and 3rd month. Group H showed a tendency towards TRX reduction, but not significantly. Serum Vit. E levels increased significantly (p < 0.0001) from the 1st to 3rd month in all three T, H and L groups. CONCLUSION: Oxidative stress induced liver damage is reduced by Vit. E in patients with viral hepatitis C, particularly those with initial ALT levels > 70 IU/l. Vit. E treatment causes reduction of oxidative stress markers as TRX and ALT in sera. Therefore, Vit. E can act as a supportive therapy to combat liver damage caused by oxidative stress, in such patients with continuously high levels of ALT even after anti-viral and anti-inflammatory drug therapy.     

Effect of vitamin E on monosodium glutamate induced hepatotoxicity and oxidative stress in rats

Monosodium glutamate (MSG), administered to rats (by gavage) at a dose of 0.6 mg/g body weight for 10 days, significantly (P<0.05) induced lipid peroxidation (LPO), decreased reduced glutathione (GSH) level and increased the activities of glutathione-s-transferase (GST), catalase and superoxide dismutase (SOD) in the liver of the animals; these were observed 24 hr after 10 days of administration. The activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma glutamyl transferase (GGT) were also significantly increased in the serum, on MSG administration. Vitamin E (0.2 mg/g body wt) co-administered with MSG, significantly reduced the LPO, increased the GSH level and decreased the hepatic activities of GST, catalase and SOD. The activities of ALT, AST and GGT in the serum were also significantly reduced. The results showed that MSG at a dose of 0.6 mg/g body wt induced the oxidative stress and hepatotoxicity in rats and vitamin E ameliorated MSG-induced oxidative stress and hepatotoxicity.     

Serum γ-glutamyltransferase: independent predictor of risk of diabetes, hypertension, metabolic syndrome, and coronary disease

Serum γ-glutamyltransferase (GGT) is associated with oxidative stress and hepatic steatosis. The extent to which its value in determining incident cardiometabolic risk (coronary heart disease (CHD), metabolic syndrome (MetS), hypertension and type 2 diabetes) is independent of obesity needs to be further explored in ethnicities. After appropriate exclusions, a cohort of 1,667 adults of a general population (age 52 ±11 years) was evaluated prospectively at 4 year's follow-up using partly Cox proportional hazard regressions. GGT activity was measured kinetically, and values were log-transformed for analyses. MetS was identified by Adult Treatment Panel-III criteria modified for male abdominal obesity. Median (interquartile range) GGT activity was 24.9 (17.0; 35.05) U/l in men, 17.0 (12.3; 24.0) U/l in women. In linear regression analysis, while smoking status was not associated, (male) sex, sex-dependent age, alcohol usage, BMI, fasting triglycerides and C-reactive protein (CRP) were significant independent determinants of circulating GGT. Each 1-s.d. increment in (= 0.53 ln GGT) GGT activity significantly predicted in each sex incident hypertension (hazard ratio (HR) 1.20 (95% confidence interval (CI) 1.10; 1.31)), and similarly MetS, after adjustment for age, alcohol usage, smoking status, BMI and menopause. Strongest independent association existed with diabetes (HR 1.3 (95% CI 1.1; 1.5)) whereas GGT activity tended to marginally predict CHD independent of total bilirubin but not of BMI. Higher serum total bilirubin levels were protective against CHD risk in women. We conclude that elevated serum GGT confers, additively to BMI, risk of hypertension, MetS, and type 2 diabetes but only mediates adiposity against CHD risk.     

Leptin,insulin and thyroid hormones in a cohort of Egyptian obese Down syndrome children: a comparative study

Oxidative stress has been implicated in the development of type 2 diabetes mellitus. Bilirubin is a potent endogenous antioxidant, and coffee is a major source of exogenous antioxidants. Serum gamma-glutamyltransferase (GGT), a marker of oxidative stress, is a strong predictor of the risk of type 2 diabetes mellitus. This study evaluated the effect modification of bilirubin and coffee consumption on the association of serum GGT with glycated hemoglobin (HbA1c) and the combined effect of bilirubin and coffee on HbA1c concentrations. The subjects were 4492 men and 6242 women aged 49–76 years who participated in the baseline survey of an on-going cohort study on lifestyle-related diseases in Fukuoka, Japan. Geometric means of HbA1c were examined according to quartile categories of GGT, with stratification by serum total bilirubin (≥ 0.6 mg/dL versus less in men and ≥ 0.5 mg/dL versus less in women) and coffee consumption (< 1, 1–3 and ≥ 4 cups of per day). Statistical adjustment was made for age, smoking, alcohol use and body mass index by using analysis of covariance. HbA1 concentrations increased progressively with increasing levels of GGT in both men and women. The increasing trend of HbA1c concentrations associated with GGT did not differ by either bilirubin status or coffee consumption. Both men and women with high bilirubin had consistently lower concentrations of HbA1c across the GGT quartiles. Higher coffee consumption was associated with lower concentrations of HbA1c in women with low bilirubin (trend P = 0.04), but not with high bilirubin (trend P = 0.37). There was no such association between coffee and HbA1c in men with either low or high bilirubin levels. Bilirubin is possibly protective against deterioration of glucose metabolism. Further studies are needed regarding the combined effect of bilirubin and coffee on glucose metabolism.     

Schistosoma mansoni: N-acetylcysteine downregulates oxidative stress and enhances the antischistosomal activity of artemether in mice

Artemether (Art), a derivative of the antimalarial artemisinin, also exhibit antischistosomal properties. N-acetylcysteine (NAC) has a diversity of applications, largely because of the chemical properties of the thiol moiety present in its structure. The ability of this moiety to sweep reactive oxygen species is well-established with NAC. This study investigates the ability of NAC to enhance the therapeutic potential of Art against adult Schistosoma mansoni infection and evaluates the protective role of this antioxidant on S. mansoni-induced oxidative stress. Mice were divided into five groups; normal (i), infected control (ii), infected treated with NAC, 300 mg/kg 5 days a week/4weeks (iii), infected treated with Art (300 mg/kg) 7 weeks post infection (iv) and infected treated with both NAC and Art (v). Results showed that Art produced a significant reduction in total number of worms when used alone. Also, it decreased hepatic ova count significantly accompanied with an increase in the percentage of dead ova. Treatment with NAC alone increased the percentage of dead ova; meanwhile, it enhanced the decrease in total number of worms and hepatic ova count when used with Art. Infection with S. mansoni significantly increased tissue GSH, GR, SOD and serum ALT and GGT, while decreased the activities of GST, GPx and the levels of proteins and albumin compared to normal control. Treatment with NAC alone approximately recovered the contents of GSH, activities of GPx and levels of serum albumin, ALT and GGT relative to normal control. A tendency for normalization in activities of the antioxidant enzymes mentioned above and serum levels of liver function tests was observed in the groups treated with Art alone or Art + NAC. Conclusion: NAC downregulates oxidative stress induced by S. mansoni infection and enhances the therapeutic potential of artemether against adult schistosomes.     

Oxidative DNA damage in circulating leukocytes occurs as an early event in chronic HCV infection

Chronic hepatitis C virus (HCV) infection is associated with an increased production of reactive oxygen species within the liver that are responsible for the oxidation of intracellular macromolecules. To ascertain whether the increased risk of hepatocellular carcinoma in individuals with chronic HCV infection is related to an accumulation of oxidative DNA damage, the 8-hydroxydeoxyguanosine (8-OHdG) content in the DNA of liver tissue and leukocytes of 87 individuals with HCV- or HBV-related liver disease and of 10 healthy controls was measured. Serum levels of thiobarbituric acid reactive substances (TBARS) were also assessed as an index of lipid peroxidation. RESULTS: The 8-OHdG content in the circulating leukocytes correlated with that of liver tissue (r = 0.618, p < .0004). HCV patients had the highest median 8-OHdG levels (p < .0004). 8-OHdG leukocyte levels in HCV patients were higher than in HBV patients (p < .04) and they significantly correlated with the clinical diagnosis (p < .025), the serum ferritin levels (p < .05), and the amount of liver steatosis (p < .001). No correlation was found with age, gender, history of drinking or smoking, ALT or GGT levels, ESR, alpha-1, or gamma-globulin level and Ishak score. TBARS levels were significantly higher in cirrhotics than in noncirrhotics (p < .01). CONCLUSIONS: The 8-OHdG level in circulating leukocytes is a reliable marker of oxidative stress occurring in the liver of individuals with chronic HCV infection. DNA oxidative damage appears to be an early and unique event in the natural history of HCV-related hepatitis. This injury increases the risk of genomic damage and may be one of the important factors involved in the carcinogenic process in cases of HCV-related chronic liver disease.     

Limited Utility of Plasma M30 in Discriminating Non-Alcoholic Steatohepatitis from Steatosis – A Comparison with Routine Biochemical Markers

Introduction

The utility of Cytokeratin-18 fragment, namely CK18Asp396 (M30), for the diagnosis of non-alcoholic steatohepatitis (NASH) is currently uncertain. We aimed to provide further data in this area among multi-ethnic Asian subjects with NAFLD.

Materials and Methods

The accuracy of M30 for detecting NASH was compared with serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma glutamyl transpeptidase (GGT) levels in consecutive adult subjects with biopsy-proven non-alcoholic fatty liver disease (NAFLD).

Results

Data for 93 NAFLD subjects (mean age 51.0±11.1 years old and 51.6% males) and 20 healthy controls (mean age 50.2±16.4 years old and 33.3% males) were analyzed. There were 39 NASH subjects (41.9%) and 54 non-NASH subjects (58.1%) among the NAFLD subjects. Plasma M30 (349 U/L vs. 162 U/L), and serum ALT (70 IU/L vs. 26 IU/L), AST (41 IU/L vs. 20 IU/L) and GGT (75 IU/L vs. 33 IU/L) were significantly higher in NAFLD subjects than in healthy controls. Serum ALT (86 IU/L vs. 61 IU/L), AST (58 IU/L vs. 34 IU/L) and GGT (97 IU/L vs. 56 IU/L) were significantly higher in NASH subjects compared to non-NASH subjects, but no significant difference was observed with plasma M30 (435 U/L vs. 331 U/L). The accuracy of plasma M30, and serum ALT, AST and GGT was good for predicting NAFLD (AUROC 0.91, 0.95, 0.87 and 0.85, respectively) but less so for NASH (AUROC 0.59, 0.64, 0.75 and 0.68, respectively). Serum ALT and AST, but not plasma M30 showed a significant trend with increasing grades of ballooning and lobular inflammation.

Conclusion

The utility of M30 in the detection of NASH in clinical practice appears limited, in comparison to routine biochemical markers.     

Robust reference intervals for Liver function test (LFT) analytes in newborns and infants

ABSTRACT: Back groundReference intervals (RIs) are ranges of upper and lower limits of a given analyte which are used for a laboratory test to determine whether a disease is present or absent or to know if the patient is at risk for future disease states. In Ethiopia, a country with highly diversified population groups and geographical sites, there are no established RIs to metabolic analytes including the liver function test (LFT) analytes for the pediatric population though it has been known that liver function assessment in this population is vital as a result of varied vulnerability to both endogenous and xenobiotic substances. METHODS: A cross sectional study was conducted in Tikur Anbessa Specialized Hospital (TASH) and Teklehaymanot Health Center (THC) from November 2010 to April 2011. 117 cord blood (from newborns) and venous blood samples (from infants) were collected and analyzed using HumaStar 300. All pre-analytical, analytical and post-analytical aspects were thoroughly controlled. A robust, CLSI/ IFCC recommended, method was used for the determination of upper and lower end points covering 95% of the reference values of each analyte with respective 90% CIs using MedCalc(R) software. RESULTS: Combined RIs for newborns and infants were established for albumin, AST, ALP, direct bilirubin and total bilirubin to be 3.88-5.82 g/dl, 16.1-55.4U/l, 130-831U/l, <0.41 mg/dl and <1.37 mg/dl respectively. But, separated RIs were indicated for ALT and GGT as 1.2-23.1U/l and 6.94-24.8U/l ALT; and 30.6-160.7U/L and 10--28.2U/l GGT for newborns and infants respectively. Some maternal and infantile factors were identified to affect the values of analytes. CONCLUSION: Almost all analytes were different from previously reported values for other target population of similar age group, kit insert values and adult values. So, interpretation of values of these analytes in newborns and infants of Ethiopian population sounds better to be performed by using such RIs taking the effect of some maternal and infantile factors in to account.     

Serum paraoxonase 1 activity and malondialdehyde levels in patients with ulcerative colitis

This study was designed to evaluate the oxidative and antioxidative status in patients with ulcerative colitis by detecting antioxidant enzyme paraoxonase 1 activity together with the level of a well-known marker of oxidative stress, malondialdehyde. Serum paraoxonase 1 activity and malondialdehyde levels were analysed in 30 patients with ulcerative colitis and 30 controls using a spectrophotometric method; correlation analysis was made between these variables. Serum malondialdehyde levels were higher in the ulcerative colitis group (median: 2.5, range: 0.5-9.4 nmol ml(-1)) than among the controls (median:1.1, range: 0.5-2.3 nmol ml(-1); p < 0.001) whereas paraoxonase 1 activities were lower in the ulcerative colitis group (median: 158.4, range: 61.6-264.1 U l(-1)) than in the control group (median: 233.3, range: 114.4-431.0 U l(-1); p < 0.001). There was no correlation between serum malondialdehyde level, paraoxonase 1 activity and disease activity. (1) Increased reactive oxygen metabolites levels in ulcerative colitis may result in a pro-oxidation environment, which in turn could result in decreased antioxidant paraoxonase 1 activity and increased malondialdehyde levels, (2) increased cytokines may be a possible cause of decreased paraoxonase 1 activity and (3) decreased serum paraoxonase 1 activity may be a part of an inflammatory response.     

Lack of induction of serum gamma-glutamyltransferase in diabetes mellitus

Some authors have suggested that carbohydrates can induce hepatic microsomal enzymes, resulting in increased serum gamma-glutamyltransferase (GGT) in diabetes mellitus. Previously we demonstrated the lack of serum GGT increases in patients with acute diabetic crises. In this work we studied serum GGT activity, blood glucose levels and glycosylated hemoglobin levels (HB A1) in 35 patients with diabetes mellitus and 27 healthy volunteers. We did not see differences in the serum GGT activity among controlled (25.05 +/- 2.72 U/l) and uncontrolled (26.44 +/- 4.05 U/l) diabetics and the control group (22.51 +/- 2.95 U/l). Also, there was no significant correlation between serum GGT and HB A1 levels in diabetic patients (r = 0.279). We think that our observations may be relevant because they support the hypothesis that hyperglycemia does not act as an enzyme-inducing agent in chronically uncontrolled diabetics and, furthermore, they indicate that in the presence of abnormal serum GGT levels in diabetics it is necessary to investigate other associated diseases.     

Comprehensive Analysis of Common Serum Liver Enzymes as Prospective Predictors of Hepatocellular Carcinoma in HBV Patients

Background

Serum liver enzymes are frequently tested in clinics to aid disease diagnosis. Large observational studies indicated that these enzymes might predict cancer risk and mortality. However, no prospective study has reported on their relationships with the risk of HBV-related hepatocellular carcinoma (HCC).

Methodology/Principal Findings

We evaluated the predictive values of four routinely tested liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and gamma-glutamyltransferase [GGT]) in HCC risk in a prospectively enrolled clinical cohort of 588 Korean American HBV patients. For all four enzymes, the baseline level as well as the average and maximum levels during the first 1 or 2 years of follow-up were analyzed using multivariate Cox proportional hazards model. Patients were categorized into a normal or an elevated group based on the clinical cut-off of each enzyme. During a median follow-up of 7.5 years, 52 patients (incidence rate, 8.8%) developed HCC. The incidence rates were higher in the elevated groups for all four enzymes. The most significant finding was for GGT, with the highest incidence rate of 16.4% in the elevated group compared to 4.6% in the normal group (P<0.001). Compared to patients with normal baseline GGT, those with elevated GGT exhibited a significantly increased HCC risk with a hazards ratio (HR) of 2.60 (95% confidence interval [CI], 1.41–4.77, P = 0.002). Further analyses revealed a cumulative effect between baseline GGT and ALP (HR = 3.41, 95% CI 1.54–7.56, P = 0.003).

Conclusions Significance

Serum GGT might predict HCC risk in HBV patients individually or jointly with other enzymes.     

Liver enzymes as a predictor for incident diabetes in a Japanese population: the Hisayama study

Objective: We studied the relationship between liver enzymes and the development of diabetes in a general Japanese population. Research Methods and Procedures: A total of 1804 non‐diabetic subjects 40 to 79 years of age were followed‐up prospectively for a mean of 9.0 years. Results: During the follow‐up, 135 subjects developed diabetes. In both sexes, the age‐adjusted cumulative incidence of diabetes increased significantly with elevating quartiles of serum γ‐glutamyltransferase (GGT) and alanine aminotransferase (ALT) levels. This pattern was also observed in aspartate aminotransferase (AST) quartiles for men but not for women. In multivariate analyses after adjusting for comprehensive risk factors and other liver enzymes, the risk of developing diabetes was significantly higher in the highest GGT quartile than in the lowest quartile [odds ratio (OR), 2.54; 95% confidence interval (CI), 1.03 to 6.26 for men; OR, 5.73; 95% CI, 1.62 to 20.19 for women]. Similar results were observed in ALT quartiles (OR, 2.32; 95% CI, 0.91 to 5.92 for men; OR, 4.40; 95% CI, 1.38 to 14.06 for women) but not in AST quartiles in either sex. Significant positive associations of GGT and ALT with diabetes were seen within each stratified category of risk factors, namely fasting insulin, BMI, waist‐to‐hip ratio, high‐sensitivity C‐reactive protein, and alcohol consumption. In receiver operating characteristic analyses, the areas under the receiver operating characteristic curve of GGT and ALT were significantly larger than that of AST, fasting insulin, waist‐to‐hip ratio, or C‐reactive protein. Discussion: Our findings suggest that serum GGT and ALT concentrations are strong predictors of diabetes in the general population, independent of known risk factors.     

Simvastatin and vitamin E effects on cardiac and hepatic oxidative stress in rats fed on high fat diet

High fat diet (HFD) is a common cause of metabolic syndrome and type 2 diabetes mellitus. Published data showed that HFD and subsequent dyslipidemia are major triggers for oxidative stress. Forty-eight male Sprague–Dawley rats, weighing 170–200 g, were divided into six groups: control, control with vitamin E (100 mg/kg/day, i.p.), control with simvastatin (SIM) (10 mg/kg of body weight/day), HFD, HFD with vitamin E, and HFD with SIM. Standard and high cholesterol diets were given for 15 weeks and SIM and vitamin E were added in the last 4 weeks. In all rats, serum vitamin E, total cholesterol (TC), triglycerides (TG), low (LDL) and high (HDL) density lipoproteins, alanine (ALT) and aspartate (AST) transaminases, alkaline phosphatase (ALP), and gamma glutamyl transpeptidase (GGT) as well as cardiac and hepatic thiobarbituric acid-reactive substances (TBARS) and antioxidants (reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT)) were measured. Also, electrocardiogram (ECG) was recorded. HFD significantly increased QTc interval, heart rate (HR), serum TC, TG, LDL, ALT, AST, ALP, GGT, liver TG, and cardiac and hepatic TBARS but decreased antioxidants and HDL, while SIM decreased HR, liver TG, serum TC, TG, and LDL and increased HDL in HFD rats. Vitamin E had no effect. Moreover, SIM and vitamin E decreased QTc interval, serum ALT, AST, ALP, GGT, and cardiac and hepatic TBARS and increased antioxidants in HFD rats. Histopathological observations confirm the biochemical parameters. SIM and vitamin E slow progression of hypercholesterolemia-induced oxidative stress in liver and heart and improve their functions.     

Hepatoprotective Effect of Manganese Chloride Against CCl4-Induced Liver Injury in Rats

The aim of the present study is to evaluate the protective effect of manganese chloride against carbon tetrachloride (CCl₄)-induced liver injury in rats. Manganese chloride (0.001, 0.01, 0.05 and 0.1 g/kg bw) was administered intragastrically for 28 consecutive days to male CCl₄-treated rats. The hepatoprotective activity was assessed using various biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), γ-glutamyltransferase (GGT) and superoxide dismutase (SOD). Histopathological changes in the liver of different groups were also studied. Administration of CCl₄ increased the serum ALT, AST, ALP and GGT but decreased SOD levels in rats. Treatment with manganese chloride significantly attenuated these changes to nearly normal levels. The animals treated with manganese chloride have shown decreased necrotic zones and hepatocellular degeneration when compared to the liver exposed to CCl₄ intoxication alone. Thus, the histopathalogical studies also supported the protective effect of manganese chloride. Therefore, the results of this study suggest that manganese chloride exerts hepatoprotection via promoting antioxidative properties against CCl₄-induced oxidative liver damage.