Association of Serum Gamma-Glutamyl Transferase and Ferritin with the Metabolic Syndrome

A New Alternative Nutritional Source Hawthorn Vinegar: How It Interacts with Protein, Glucose and GLP-1

(1) Background: There is a balance between nutrition, glycemic control, and immune response. Their roles in physiological mechanisms are essential for maintaining life quality. This study aimed to evaluate hawthorn vinegar's metabolic effects, and describe its possible mechanism. We also pointed out several vinegar production methods to clarify the antioxidant features. (2) Methods: In the study, three vinegar techniques were applied to vinegar: traditional production of hawthorn vinegar (N), thermal pasteurization (P), and ultrasound method (U). Thirty-two female adult Wistar albino rats were randomly separated into four groups: Control, N1 (regular vinegar; 1 mL/kg bw), P1 (pasteurized vinegar; 1 mL/kg bw), and U1(ultrasound treated vinegar; 1 mL/kg bw). Vinegar was administered by oral gavage daily for 45 days. Initial and final weights, the percentage changes of body weight gains, and Gamma-Glutamyl Transferase (GGT) values of plasma and liver were measured. The total protein, globulin, and albumin values of plasma, liver, and intestinal tissue were determined. In addition, plasma glucagon-like peptide-1 (GLP-1) and glucose concentrations were evaluated. (3) Results: There was a statistical increase in total intestinal protein value and an increasing tendency in total protein in plasma and liver in group U1 compared to group Control. However, the GGT concentrations in plasma and liver were slightly lower in group U1 than in group Control. In addition, there were significant increases in plasma GLP-1 values in all experimental groups compared to the Control group (p: 0.015; 576.80 ± 56.06, 773.10 ± 28.92, 700.70 ± 17.05 and 735.00 ± 40.70; respectively groups control, N1, P1, and U1). Also, liver GLP-1 concentrations in groups P1 and U1 were higher than in group Control (p: 0.005; 968.00 ± 25.54, 1176 ± 17.54 and 1174.00 ± 44.06, respectively groups control, P1 and U1). On the other hand, significant decreases were found in plasma glucose concentrations in groups N1 and U1 as to the Control group (p: 0.02; Control: 189.90 ± 15.22, N1: 133.10 ± 7.32 and U1: 142.30 ± 4.14). Besides, liver glucose levels were lower in all experimental groups than in group Control statistically (p: 0.010; 53.47 ± 0.97, 37.99 ± 1.46, 44.52 ± 4.05 and 44.57 ± 2.39, respectively groups control, N1, P1, and U1). (4) Conclusions: The findings suggest that hawthorn vinegar can balance normal physiological conditions via intestinal health, protein profiles, and glycemic control. Additionally, ultrasound application of vinegar may improve the ability of hawthorn vinegar, and have positive effects on general health.

Serum Gamma Glutamyltransferase: A Biomarker for Identifying Postprandial Hypertriglyceridemia

Purpose

Elevated serum gamma-glutamyltranspeptidase (GGT) is an independent marker of the activation of systemic inflammation, while conditions associated with elevated triglyceride (TG) levels, such as type 2 diabetes, non-alcoholic fatty liver disease, obesity, and metabolic syndrome, are associated with an increased inflammatory burden. Moreover, serum liver enzymes (GGT, alanine aminotransferase [ALT], aspartate aminotransferase [AST], and alkaline phosphatase [ALP]) are associated with metabolic syndrome and its components, including hypertriglyceridemia. However, the relationship between liver enzymes and postprandial hypertriglyceridemia (PHTG) remains unclear. Therefore, in this study we conducted oral fat tolerance tests (OFTTs) to understand the differences in serum liver enzyme levels among individuals with different lipid tolerance levels and their correlation with PHTG.

Patients and Methods

 For the OFTT, we enrolled 202 non-diabetic volunteers whose fasting triglyceride (TG) levels were less than 1.7 mmol/L in this case-control study. The participants were categorized into two groups according to the TG levels at the 0- and 4-h OFTT: a postprandial normal TG (PNTG) group and a PHTG group. Routine fasting serum biochemical indices, liver enzyme (GGT, ALT, AST, and ALP) levels, and 0- and 4-h OFTT lipid levels were assessed.

Results

The PHTG group had significantly higher serum GGT and ALT levels and a lower AST/ALT ratio than those in the PNTG group. However, no significant difference was observed in AST and ALP levels compared with the PNTG group. After adjusting for major confounders, logistic regression analysis indicated a significant correlation between serum GGT and PHTG (odds ratio = 1.168, P < 0.001), but not with ALT level, AST level, AST/ALT ratio, and ALP level. The receiver operating characteristic curve analysis demonstrated that the serum GGT level was an effective predictor of PHTG.

Conclusion

Serum GGT levels are significantly associated with PHTG risk and serve as an effective biomarker for early identification.

The association of psychological stress with metabolic syndrome and its components: cross-sectional and bidirectional two-sample Mendelian randomization analyses

Background

Metabolic syndrome (MetS) is a group of co-occurring conditions that increase the risk of cardiovascular disease, which include the conditions of hypertension, overweight or obesity, hyperglycemia, and dyslipidemia. Psychological stress is gradually being taken seriously, stemming from the imbalance between environmental demands and individual perceptions. However, the potential causal relationship between psychological stress and MetS remains unclear.

Method

We conducted cross-sectional and bidirectional Mendelian randomization (MR) analyses to clarify the potential causal relationship of psychological stress with MetS and its components. Multivariable logistic regression models were used to adjust for potential confounders in the cross-sectional study of the Chinese population, including 4,933 individuals (70.1% men; mean age, 46.13 ± 8.25). Stratified analyses of sexual characteristics were also performed. Bidirectional MR analyses were further carried out to verify causality based on summary-level genome-wide association studies in the European population, using the main analysis of the inverse variance-weighted method.

Results

We found that higher psychological stress levels were cross-sectionally associated with an increased risk of hypertension in men (odds ratio (OR), 1.341; 95% confidence interval (CI), 1.023-1.758; p = 0.034); moreover, higher levels of hypertension were cross-sectionally associated with an increased risk of psychological stress in men and the total population (men: OR, 1.545 (95% CI, 1.113-2.145); p = 0.009; total population: OR, 1.327 (95% CI, 1.025-1.718); p = 0.032). Genetically predicted hypertension was causally associated with a higher risk of psychological stress in the inverse-variance weighted MR model (OR, 2.386 (95% CI, 1.209-4.710); p = 0.012). However, there was no association between psychological stress and MetS or the other three risk factors (overweight or obesity, hyperglycemia, and dyslipidemia) in cross-sectional and MR analyses.

Conclusion

Although we did not observe an association between psychological stress and MetS, we found associations between psychological stress and hypertension both in cross-sectional and MR studies, which may have implications for targeting hypertension-related factors in interventions to improve mental and metabolic health. Further study is needed to confirm our findings.

Aspartate aminotransferase/alanine aminotransferase ratio was associated with type 2 diabetic peripheral neuropathy in a Chinese population: A cross-sectional study

OBJECTIVE

Despite previous research that focused on aspartate aminotransferase/alanine aminotransferase ratio (AAR) as predictors of type 2 diabetes mellitus (T2DM) and cardiovascular disease, there has been limited research evaluating the association between AAR and diabetic microvascular complications. This study aimed to investigate the association of AAR with diabetic peripheral neuropathy (DPN).

METHODS

A total of 1562 hospitalized patients with T2DM were divided into four groups according to AAR quartiles. The relationship between AAR and DPN and related parameters was explored by the Spearman correlation coefficients, multivariable logistic regression analysis, and receiver operating characteristic (ROC) curves.

RESULTS

Patients with higher AAR quartiles had higher levels of vibration perception threshold (VPT) and presence of DPN, and AAR was positively associated with VPT and presence of DPN independent of sex, age, body mass index, and diabetic duration (P<0.01 or P<0.05). Moreover, AAR remained significantly associated with a higher odds ratio (OR) of DPN (OR 2.413, 95% confidence interval [CI] 1.081-5.386, P<0.05) after multivariate adjustment. Additionally, the risk of presence of DPN increased progressively as AAR quartiles increased (all P for trend <0.01) in both male and female subjects, and the highest quartile of AAR of male and female subjects was respectively associated with 107.3% (95% CI: 1.386-3.101; P<0.01) and 136.8% (95% CI: 1.550-3.618; P<0.01) increased odds of DPN compared with the lower quartiles. Last, the analysis of receiver operating characteristic curves revealed that the best cutoff values for AAR to predict the presence of DPN were 0.906 (sensitivity: 70.3%; specificity: 49.2%; and area under the curve [AUC]: 0.618) and 1.402 (sensitivity: 38%; specificity: 81.9%; and AUC: 0.600) in male and female subjects, respectively.

CONCLUSIONS

These findings suggest that the high AAR may be associated with the presence of DPN in Chinese patients with T2DM, and may be used as an additional indicator of risk of DPN.

Obese Vegetarians and Omnivores Show Different Metabolic Changes: Analysis of 1340 Individuals

Our study evaluated the association between the increase in body mass index (BMI) in men and women (menstruating and non-menstruating) (n = 1340) with different dietary groups (omnivores, semi-vegetarians, lacto-ovo-vegetarian, and vegans) and the measurement of the biochemical markers high-sensitive C-reactive protein (hs-CRP), ferritin, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), glycated hemoglobin (HbA1C), and insulin resistance index (HOMA-IR). Increasing BMI values in all groups and dietary profiles were related to a significant increase in hs-CRP (p < 0.0001), ALT (p = 0.02), ferritin (p = 0.009), and HbA1C (p < 0.0001), with no difference between dietary groups (p < 0.05). The increase in BMI increases the levels of HOMA-IR (p < 0.0001) and GGT (p < 0.05), with higher values found in men when compared to women (p < 0.0001 for HOMA- IR and p = 0.0048 for GGT). The association between ALT and BMI was different between dietary groups, as it showed a decrease in vegan women who do not menstruate compared to other dietary groups (p = 0.0099). When including only obese individuals (BMI ≥ 30 kg/m2, n = 153) in the analysis, we observed lower concentrations of GGT and ferritin in vegetarians than in omnivores, regardless of gender and menstrual blood loss (p = 0.0395). Our data showed that for both vegetarians and omnivores, the higher the BMI, the worse the metabolic parameters. However, regarding obesity, vegetarians showed better antioxidant status (lower GGT elevation) and lower inflammatory status (lower ferritin elevation), which may provide them with potential protection in the development of morbidities associated with overweight.

Relationship Between Serum Gamma-Glutamyl Transferase Level and Impaired Fasting Glucose Among Chinese Community-Dwelling Adults: A Follow-Up Observation of 6 Years

Objective: We aimed to investigate the relationship between serum gamma-glutamyl transferase (GGT) and fasting blood glucose (FBG) levels, as well as the cumulative risk of impaired fasting glucose (IFG) regulation in the Chinese adult population after 6 years of follow-up. Methods: A total of 1360 apparently healthy Chinese men and women who completed a community-based health examination survey and did not have IFG in central China in 2010 and 2016 were included in this study. The patients were divided into four groups according to their baseline GGT (in quartiles). The relationship between GGT levels and FBG levels was examined using general linear regression models. The effect of the GGT level on the risk of IFG was analyzed using multivariate logistic regression. The first quartile group of GGT levels was set as the dummy variable in the model, and the odds ratios and 95% confidence intervals of the remaining quartile groups relative to the first quartile group were obtained. Results: After 6 years of follow-up, 16.4% (188/1148) of participants were diagnosed with IFG. The cumulative incidence of IFG in the four groups according to their baseline GGT levels (in quartiles) was 7.7%, 16.1%, 15.8%, and 26.8%, respectively. Based on the Cox multiple regression, the hazard ratio for IFG increased by 28.9% for each unit of increase in the baseline GGT level after adjusting for the confounding factors. The GGT levels of participants in the first quartile were used as the reference group. The relative risks of IFG in the second, third, and fourth quartiles of GGT were 1.70, 1.55, and 2.46, respectively (P = 0.005). Conclusions: GGT was positively associated with the risk of IFG and can be used as an indicator to assess whether a patient may develop prediabetes.

Influence of melatonin on the kidneys of rats with experimental diabetes mellitus type 2

Diabetes mellitus is characterized by numerous pathological changes in the body. Under conditions of diabetes, hyperglycemic intoxication of the organism rapidly develops, which in turn leads to an increase of oxidative stress with subsequent disturbance of the anatomical and functional integrity of the components of organisms. Today, the search for the substances that would contribute to the multi-vectoral effect on the negative consequences of diabetes is actively being pursued. Melatonin is one of such substances. In this work, we studied the effect of melatonin on oxidative stress markers (oxidized products content, activities of superoxide dismutase and catalase), the concentration of metabolism end products (creatinine and urea), main ions concentration (potassium and chlorine), and protein content (total protein and electropherogram in polyacrylamide gel), enzymatic activity of gamma-glutamyltrasferase in the cytosolic fraction of rat kidneys under condition of type 2 diabetes mellitus (EDM2). Experimental studies were performed on 18 white adult Wistar rats divided into three groups (control, group with EDM2 and group with EDM2, which were treated with melatonin). The increase of concentration of oxidized products, the activity of catalase and gamma-glutamyltrasferase, creatinine, urea, K+ and Cl– and the decrease of concentration of superoxide dismutase in the rats’ kidneys was noted after development of EDM2. The electrophoretic proteinogram of the cytosolic proteins obtained from the rats’ kidneys showed an increase of content of high-molecular-weight and a decrease of low-molecular-weight proteins. Administration of melatonin in a dose of 10 mg/kg of body weight for 7 days after development of EDM2 restored the studied parameters almost to the control group values. Therefore, the influence of melatonin can prevent chronic development of oxidative stress in kidneys under hyperglycemic intoxication, and lead to normalization of kidney function and the restoration of homeostasis.

Serum GGT and serum ferritin as early markers for metabolic syndrome

Background:

In India, the prevalence of lifestyle diseases like diabetes, hypertension, and metabolic syndrome (MetS) is showing an upward trend. Gamma glutamate transferase (GGT) and ferritin increase oxidant stress in the body through their role in glutathione homeostasis and iron metabolism, respectively. The increase in oxidant stress increases the inflammatory load, a risk factor for metabolic syndrome. These parameters are cheap, patient-friendly, and available in routine diagnostic labs compatible for follow-up, relieving the already overburdened healthcare system.

Methodology:

In a case-control study, samples of 77 cases of metabolic syndrome and 77 age and sex-matched controls were analyzed for serum GGT (by modified IFCC) and serum ferritin (by CLIA). Statistical analysis was done by SPSS 20.0 version.

Results:

The mean ± SD for ferritin and GGT were 101.58 ± 84.20 ng/dL and 36.67 ± 26.40 IU/L, respectively in cases, whereas in control group these values were 38.38 ± 29.26 ng/dL and 16.5 3 ± 6.79 IU/L (P < 0.001). Positive and significant correlation was seen between GGT with TG (r-value- 0.376/P-value-0.001) and GGT with waist circumference (r-value- 0.298/P-value- 0.022). A positive and significant correlation was seen between GGT and ferritin in cases with an r-value of 0.307 (P-value - 0.01).

Conclusion:

The increased values of GGT and ferritin in cases suggest an inflammatory load. The positive and significant correlation between GGT and triglyceride indicates its role in increasing oxidants’ stress leading to inflammation and the development of MetS. The association of ferritin with MetS though insignificant may be considered as a biomarker.

Associations of iron markers with type 2 diabetes mellitus and metabolic syndrome: Results from the prospective SHIP study

AIMS

To assess the role of serum ferritin and transferrin with prevalent and incident type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS) and whether these associations are independent of inflammatory markers and hepatic enzymes.

METHODS

We analyzed data from 3,232 participants aged 20-81 years of the population-based Study of Health in Pomerania (SHIP) from Northeast Germany with a median follow-up time of 10.6 years. Logistic and Cox regression analyses were performed.

RESULTS

Serum ferritin concentrations were associated with a higher prevalence of T2DM (total population OR: 1.16 [95% CI: 1.07, 1.26]; men OR: 1.18 [95% CI: 1.08, 1.30) and MetS (total population OR: 1.27 [95% CI: 1.16, 1.38]; men OR: 1.26 [95% CI: 1.15, 1.38]) in the total population and men independently of inflammatory markers and hepatic enzymes. In longitudinal analyses, baseline ferritin concentrations were associated with a higher risk of incident T2DM in women (HR: 1.38 [95% CI: 1.10, 1.71]), but not in men or in the total population and also with a higher risk of incident MetS (HR: 1.09 [95% CI: 1.01, 1.17]) in the total population. These longitudinal associations attenuated considerably after adjustment for hepatic enzymes but not inflammatory markers. Transferrin was not associated with any of the outcomes.

CONCLUSIONS

Our results suggest a link between ferritin and T2DM and MetS, which might be partially explained by hepatic dysfunction.

Association of serum ferritin with metabolic syndrome in eight cities in China

Objective

This study aims to evaluate the cross‐sectional association of serum ferritin (SF) and the risk of metabolic syndrome (MetS) and its components among adults in eight cities in China.

Methods

Subjects were recruited using a combination of systematic cluster random sampling and purposive sampling in eight cities in China. The sociodemographic characteristics, data of lifestyle factors, self‐reported disease history, and 24‐hr dietary intake were obtained using a validated questionnaire. Anthropometry was performed, and fasting blood was collected to test the SF, fasting blood glucose (FBG), insulin, high‐sensitivity C‐reactive protein (hs‐CRP), triglycerides (TG), and cholesterols. Logistic and linear regression analyses were conducted to investigate the associations, adjusting for age, city level, smoking, drinking, weekly moderate‐to‐vigorous activity, dietary factors, hs‐CRP, and BMI.

Results

Serum ferritin level is positively correlated with total cholesterol, TG, FBG, HOMA‐IR, and hs‐CRP after adjusting for age and BMI. The odds ratio (OR) for MetS in the highest quartile of SF was 2.23 (1.32, 3.77) after adjusting for men, compared with the lowest quartile. An elevated ferritin concentration was significantly related to hypertriglyceridemia (p < .001) and elevated glucose (p = .013) among men, but not among women. Furthermore, compared with Q1, the OR for insulin resistance in the ferritin Q4 group was 3.08 (1.50, 6.32) among men and 1.96 (1.19, 3.24) among women.

Conclusion

A positive association between elevated SF and MetS and its components including hypertriglyceridemia and elevated glucose was found in multivariate analyses among men, and SF levels are independently associated with IR.

Atrial fibrillation and gamma glutamyl transferase; Off-pump versus on-pump Coronary Artery Bypass surgery

Introduction: Atrial fibrillation (AF) which can be seen as a complication of the open-heart surgery, may cause serious problems on postoperative period. The exact pathophysiology of AF is unknown but it is thought that factors such as oxidative stress might cause AF. Material and methods: We retrospectively surveyed the serum gamma-glutamyl transferase (GGT) levels which is accepted as a mediator of oxidative stres, for the Post Operative Atrial Fibrillation (POAF) that occur after of-pump versus on-pump Coronary Artery Bypass Graft (CABG) surgery. Our study included 183 cases (101 male, 72 female; median age 63 ± 4.3 years) of which CABG was performed. Results: Echocardiography, routine blood tests, electrocardiography (ECG), test for the serum GGT levels were performed in preoperative and postoperative period to all participants. AF developed in 34 patients (35 %) in Group I and 19 patients (20 %) in Group II. There were no significant differences between two groups (of-pump versus on-pump) in terms of gender, cardiovascular risk factors and the severity of the coronary artery disease. In patients who has developed AF in postoperative period had significantly higher serum GGT levels. Conclusion: This study has shown that serum GGT levels were found to be significantly higher in patients whom AF has developed after on-pump CABG surgery.

Risk factors associated with nonalcohol fatty liver disease and fibrosis among patients with type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) is closely related to hepatic steatosis and fibrosis. The aim of this study was to analyze the occurrence of hepatic steatosis and fibrosis in patients with T2DM and to explore the risk factors.A total of 629 patients with T2DM were enrolled. Liver stiffness value (LSV) and controlled attenuation parameters (CAP) were measured using Fibroscan. Liver fibrosis was diagnosed when LSV was greater than 7.4 kPa, and advanced liver fibrosis was diagnosed when LSV was greater than 10.6 kPa. Hepatic steatosis diagnosis was made when CAP value was greater than 238 dB/m. Demographic information, physical examination data, and laboratory tests results were collected. The 629 patients were classified into 2 groups by the liver fibrosis and liver steatosis, and then the difference was analyzed.Among patients enrolled, 231 patients were diagnosed as liver fibrosis. The age of the patients in the fibrosis group was significantly greater than that in the non-fibrosis group, and similar trends were observed in the waist-hip ratio (WHR), systolic blood pressure, and diastolic blood pressure. The proportion of smoking and alcoholic consumption was significantly lower in patients with non-fibrosis group. A total of 426 patients were diagnosed with liver steatosis. Body mass index (BMI), WHR, systolic blood pressure, and diastolic blood pressure in patients with steatosis were significantly higher than those in non-steatosis group. We observed that the LSV (P = .042) and CAP value (P < .001) are positively correlated with metabolic syndrome components in T2DM patients. Older age (OR = 1.099, P = .001), high BMI (OR = 1.088, P = .003), low platelet level (OR = 0.996, P = .014), and smoking (OR = 1.653, P = .013) were independent risk factors of liver fibrosis among T2DM patients. High BMI (OR = 1.369, P < .001), high diastolic blood pressure (OR = 1.048, P < .001), and high gamma glutamyl transpeptidase (OR = 1.018, P = .009) were independent risk factors for liver steatosis among T2DM patients.This study suggested risk factors screening of liver fibrosis and steatosis. Timely intervention should be taken into consideration among high risk patients to prevent progress liver diseases.

Targeting Colon Luminal Lipid Peroxidation Limits Colon Carcinogenesis Associated with Red Meat Consumption

Red meat is probably carcinogenic to humans (WHO/IARC class 2A), in part through heme iron-induced lipoperoxidation. Here, we investigated whether red meat promotes carcinogenesis in rodents and modulates associated biomarkers in volunteers, speculating that an antioxidant marinade could suppress these effects via limitation of the heme induced lipid peroxidation. We gave marinated or non-marinated beef with various degrees of cooking to azoxymethane-initiated rats, Min mice, and human volunteers (crossover study). Mucin-depleted foci were scored in rats, adenoma in Min mice. Biomarkers of lipoperoxidation were measured in the feces and urine of rats, mice, and volunteers. The organoleptic properties of marinated meat were tested. Fresh beef increased colon carcinogenesis and lipoperoxidation in rats and mice and lipoperoxidation in humans. Without an adverse organoleptic effect on meat, marinade normalized peroxidation biomarkers in rat and mouse feces, reduced peroxidation in human feces and reduced the number of Mucin-depleted foci in rats and adenoma in female Min mice. This could lead to protective strategies to decrease the colorectal cancer burden associated with red meat consumption. Cancer Prev Res; 11(9); 569-80. ©2018 AACR.

Plasma Neuregulin 4 Levels Are Associated with Metabolic Syndrome in Patients Newly Diagnosed with Type 2 Diabetes Mellitus

Neuregulin 4 (Nrg4) has been proposed to play a role in the pathogeneses of obesity, insulin resistance, and dyslipidemia. However, information about the link between Nrg4 and metabolic syndrome (MetS) is scarce, especially in patients with newly diagnosed type 2 diabetes mellitus (nT2DM). This study aimed at investigating whether Nrg4 is associated with MetS in nT2DM patients. A total of 311 patients with nT2DM were recruited. Plasma Nrg4 concentration was determined by ELISA. Plasma Nrg4 concentration was lower in nT2DM patients with MetS than in nT2DM patients without MetS (P = 0.001). Nrg4 concentration showed negative correlations with most of the analyzed indicators of MetS. MetS was less prevalent among subjects in the highest quartile of plasma Nrg4 concentration than among those in the lowest quartile (P < 0.01). Age- and sex-adjusted plasma Nrg4 concentrations were positively correlated with concentrations of high-density lipoprotein cholesterol (HDL-C) and apolipoprotein A (both P < 0.05) and negatively correlated with triglyceride, high-sensitivity C-reactive protein (hs-CRP), and gamma-glutamyltransferase concentrations, neutrophil count, and white blood cell (WBC) count (all P < 0.05). In multivariate analysis, Nrg4 was independently associated with hs-CRP level, WBC count, and HDL-C level (P = 0.001 or P < 0.05). Multiple logistic regression analysis of MetS prediction by Nrg4 revealed an odds ratio of 0.560 (95% CI: 0.374-0.837; P < 0.01). Decreased plasma Nrg4 levels, which may be associated with augmented oxidative stress, inflammation, and dyslipidemia, might be involved in the development of MetS in nT2DM patients.

Relationship between serum gamma-glutamyltransferase activity and cardiometabolic risk factors in metabolic syndrome

Objectives

The objective of this study was to examine the associations of serum gamma-glutamyltransferase (GGT) levels with the metabolic syndrome (MetS) and its components in Saudi adults.

Methods

The study comprised 400 participants (70 men and 330 women), aged between 40 and 88 years, randomly selected from the medicine clinics at the King Abdulaziz University Hospital in Jeddah, Saudi Arabia, in a cross-sectional study design. A standardized questionnaire was used to determine demographics variables, general health, lifestyle habits, and medical history. Anthropometric and biochemical variables measurements were taken for all study participants. MetS was defined according to the American Heart Association/National Heart, Lung, and Blood Institute report, by the presence of abdominal obesity.

Results

Higher means for triglycerides and insulin resistance indices (P < 0.0001) was found among those in the second, third, and fourth GGT quartiles as compared with their counterparts in the first quartile. McAuley index (β = -0.239, P < 0.0001, 95% confidence interval: -4.1--1.5) was shown to be a major determinant of circulating GGT in a multivariate analysis.

Conclusion

Elevated serum GGT could be a cardiometabolic risk factor either as a mediator of low-grade systemic inflammation and as a mediator of oxidative stress through mediation of extracellular glutathione transport into cells of organ systems.

Dose-Response Relationship between Alanine Aminotransferase Levels within the Reference Interval and Metabolic Syndrome in Chinese Adults

PURPOSE

Elevation in serum alanine aminotransferase (ALT) levels is a biomarker for metabolic syndrome (MS); however, the relationship has not been fully investigated within the reference interval of ALT levels. Our objective was to explore the relationship between serum ALT levels within the reference interval and MS in Chinese adults.

MATERIALS AND METHODS

This cross-sectional study included 16028 adults, who attended routine health check-ups at Shengli Oilfield Central Hospital from January 2006 to March 2012. The reference interval of serum ALT level was defined as less than 40 U/L. Logistic regression models and restricted cubic spline were used to evaluate the association of ALT with MS.

RESULTS

The prevalence of MS in the total population was 13.7% (6.4% for females and 18.4% for males). Multiple logistic regression showed that ALT levels were positively associated with MS after adjustment for potential confounding factors. The odds ratio of MS in the top quartile was 4.830 [95% confidence interval (CI): 2.980-7.829] in females and 3.168 (95% CI: 2.649-3.790) in males, compared with the ALT levels in the bottom quartile. The restricted cubic spline models revealed a positive non-linear dose-response relationship between ALT levels and the risk of MS in women (p for nonlinearity was 0.0327), but a positive linear dose-response relationship in men (p for nonlinearity was 0.0659).

CONCLUSION

Serum ALT levels within the reference interval are positively associated with MS in a dose-response manner. Elevated ALT levels, even within the reference interval, may reflect early dysmetabolic changes.

Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood biochemical profile. Pancreatic toxicity was measured by inflammatory parameters, cell viability and cycle, free radical generation, and proteomic profile on islets of Langerhans. In vivo PCB126 exposure enhanced the body weight gain, impaired insulin sensitivity, reduced adipose tissue deposit, and elevated serum triglycerides, cholesterol, and insulin levels. Inflammatory parameters in the pancreas and cell morphology, viability and cycle were not altered in islets of Langerhans. Nevertheless, in vivo PCB126 exposure increased free radical generation and modified the expression of proteins related to oxidative stress on islets of Langerhans, which are indicative of early β-cell failure. Data herein obtained show that long-term in vivo PCB126 exposure through intranasal route induced alterations on islets of Langerhans related to early end points of DM2.

Gamma-Glutamyltransferase: A Predictive Biomarker of Cellular Antioxidant Inadequacy and Disease Risk

Gamma-glutamyltransferase (GGT) is a well-established serum marker for alcohol-related liver disease. However, GGT's predictive utility applies well beyond liver disease: elevated GGT is linked to increased risk to a multitude of diseases and conditions, including cardiovascular disease, diabetes, metabolic syndrome (MetS), and all-cause mortality. The literature from multiple population groups worldwide consistently shows strong predictive power for GGT, even across different gender and ethnic categories. Here, we examine the relationship of GGT to other serum markers such as serum ferritin (SF) levels, and we suggest a link to exposure to environmental and endogenous toxins, resulting in oxidative and nitrosative stress. We observe a general upward trend in population levels of GGT over time, particularly in the US and Korea. Since the late 1970s, both GGT and incident MetS and its related disorders have risen in virtual lockstep. GGT is an early predictive marker for atherosclerosis, heart failure, arterial stiffness and plaque, gestational diabetes, and various liver diseases, including viral hepatitis, other infectious diseases, and several life-threatening cancers. We review literature both from the medical sciences and from life insurance industries demonstrating that serum GGT is a superior marker for future disease risk, when compared against multiple other known mortality risk factors.