Relationships between serum adiponectin with metabolic syndrome and components of metabolic syndrome in non-diabetic Koreans: ARIRANG study

Blood and Urinary Biomarkers of Antipsychotic-Induced Metabolic Syndrome

Metabolic syndrome (MetS) is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL). Antipsychotic (AP)-induced MetS (AIMetS) is the most common adverse drug reaction (ADR) of psychiatric pharmacotherapy. Herein, we review the results of studies of blood (serum and plasma) and urinary biomarkers as predictors of AIMetS in patients with schizophrenia (Sch). We reviewed 1440 studies examining 38 blood and 19 urinary metabolic biomarkers, including urinary indicators involved in the development of AIMetS. Among the results, only positive associations were revealed. However, at present, it should be recognized that there is no consensus on the role of any particular urinary biomarker of AIMetS. Evaluation of urinary biomarkers of the development of MetS and AIMetS, as one of the most common concomitant pathological conditions in the treatment of patients with psychiatric disorders, may provide a key to the development of strategies for personalized prevention and treatment of the condition, which is considered a complication of AP therapy for Sch in clinical practice.

Serum leptin level and incidence of CKD: a longitudinal study of adult enrolled in the Korean genome and epidemiology study(KoGES)

Background

Chronic kidney disease(CKD) is a major public health issue and is highly prevalent in the general population. Leptin is an adipose tissue-derived endocrine factor that has been associated with several metabolic factors involved in cardiovascular diseases. Several studies have investigated the association between leptin and renal diseases so far. But the results are conflicting between the studies. The objective of our study was to verify the direct association of serum leptin level with CKD development.

Methods

This prospective cohort study included 2646 adult aged 40–70 without CKD in the Korean Genome and Epidemiology Study(KoGES) across South Korea from November 2005 to February 2012. The primary outcome was the development of CKD as defined by National Kidney Foundation Kidney Disease Outcomes Quality Initiative (KDOQI). Multivariate stepwise logistic regression analysis was done to assess the independent associations, for with the incident of CKD as the dependent variable, in tertiles of leptin values.

Results

Among 1100 men and 1546 women with 2.8 mean years of follow-up, incidence of CKD was 18(1.63%) for men and 50(3.23%) for women. In the multivariate logistic regression models, individuals in the highest serum leptin tertile showed significant associations with risk of CKD after adjustment compared to the lowest tertiles in the population. The crude odds ratio for trend was 2.95(p = 0.004) for men. After adjusting for age, baseline eGFR variables showed correlation with statistical significance (OR for trend = 2.25, p = 0.037) for men. The same trends were also seen observed in all population and women also, but no statistical significance was found.

Conclusions

Higher plasma leptin levels are associated with the incidence of CKD, independent of traditional factors such as age, baseline eGFR. Our results suggest that leptin may partly explain part of the reported association between obesity and kidney disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02795-7.

Plasminogen activator inhibitor-1 mediate downregulation of adiponectin in type 2 diabetes patients with metabolic syndrome

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Both Adiponectin and PAI-1 levels are associated with the Metabolic abnormalities.

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This study demonstrates that subjects with MetS have low adiponectin and higher PAI-1 levels compare to non-MetS.

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Higher PAI-1 levels are associated with higher odds of risk and prevalence of MetS.

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Pharmacological targeting of PAI-1 is necessary for MetS management.

Introduction

Metabolic syndrome (MetS) is a multifactorial disease characterized by metabolic abnormalities. Plasminogen activator inhibitor-1(PAI-1) is a key factor of the fibrinolysis its expression is elevated in insulin resistance, obesity, and MetS. In addition, an adiponectin produced by adipocytes is also key factor in MetS. This study aimed to investigate the relationship between PAI-1, adiponectin levels in MetS.

Patients and Methods

A total of 379 subjects were analyse in this cross-sectional study. MetS was defined by NCEP ATP-III criteria. Anthropometric, fasting blood glucose, HbA1c, total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, PAI-1, and adiponectin were measured.

Results

PAI-1 levels were higher in MetS compared with non-MetS. In addition, adiponectin levels were significantly lower in MetS compared to non-MetS. Furthermore, increased level of PAI-1 corresponds with increase in prevalence of MetS. PAI-1 levels were significantly associated with MetS (OR = 2.51, CI = 1.23 – 5.14; p = 0.039).

Conclusion

PAI-1 increases the risk of MetS. PAI-1 and adiponectin regulation is useful in assesing the presence and severity of MetS. Further pharmacological targeting of PAI-1 studies are necessary for MetS management.

Prospective Associations of Serum Adiponectin, Leptin, and Leptin-Adiponectin Ratio with Incidence of Metabolic Syndrome: The Korean Genome and Epidemiology Study

Although the role of adiponectin and leptin in the etiology of metabolic syndrome (MetS) has been explored in various populations, limited knowledge is available on the prospective association of adiponectin and leptin with the risk of MetS development. The present study aimed to evaluate the associations of adiponectin, leptin, and the leptin-adiponectin (LA) ratio with the future risk of MetS in middle-aged and older Korean adults. Using a prospective, population-based Ansan-Ansung cohort of the Korean Genome and Epidemiology Study (KoGES), 2691 Korean adults (1317 men and 1374 women) were included in the present study. Serum adiponectin and leptin concentrations were measured using commonly available enzyme-linked immunosorbent assay kits. Multivariable Cox proportional hazard models were used to investigate the relationships of the different adiponectin and leptin concentrations and LA ratio with the incident MetS. During a mean follow-up of 6.75 years, a total of 359 (27.26%) men and 385 (28.02%) women were identified as developing new-onset MetS. After controlling for covariates, higher adiponectin levels were associated with lower incidence of MetS (hazard ratio (HR) for third vs. first tertile: 0.53, 95% confidence interval (CI): 0.40–0.70 for men and HR: 0.54, 95% CI: 0.42–0.71 for women), while higher leptin levels (HR for third vs. first tertile: 2.88, 95% CI: 2.01–4.13 for men and HR: 1.55, 95% CI: 1.13–2.13 for women) and LA ratio (HR for third vs. first tertile: 3.07, 95% CI: 2.13–4.44 for men and HR: 1.94, 95% CI: 1.41–2.66 for women) were associated with an increased incidence of MetS. Among men, in the fully adjusted models an increase by one standard deviation (SD) in adiponectin levels was associated with a 10% decrease in MetS risk (HR per SD: 0.90, 95% CI: 0.85–0.95) while leptin and LA ratio was associated with a 5% (HR per SD: 1.05, 95% CI: 1.01–1.08) and 40% (HR per SD: 1.40, 95% CI: 1.22–1.62) increase in MetS risk, respectively. Among women, a significant association with MetS risk was observed only in adiponectin levels (HR per SD: 0.91, 95% CI: 0.88–0.95). We found that higher adiponectin level was associated with a lower risk of MetS, while higher leptin level and LA ratio were associated with elevated MetS incidence, irrespective of body mass index at baseline in both Korean men and women. Adiponectin and leptin levels and LA ratio could play a role as a useful biomarker in the prediction of future MetS development among middle-aged and older Koreans.

Influence of inflammation and adipocyte biochemical markers on the components of metabolic syndrome

Metabolic syndrome is associated with increased risk of cardiovascular disease. This study investigated the correlation between adipocyte and inflammation biomarkers, and metabolic syndrome and its components. The study included 80 patients with normal body-mass index and 80 obese patients. The groups were assessed for serum values of adiponectin, leptin and highly sensitive C reactive protein (hsCRP), the homeostatic model assessment of insulin resistance (HOMA-IR), as well as the influence of these biochemical markers on the prevalence of metabolic syndrome and its components. Leptin, HOMA-IR and hsCRP had statistically significant (P<0.01) higher values in the group of obese subjects, while adiponectin had statistically significant (P<0.01) lower values. The prevalence of metabolic syndrome was 35% in the obese group and 5% in the normal weight group. Adiponectin and HOMA-IR were the variables significantly associated with metabolic syndrome (P<0.01), adiponectin/HOMA-IR ratio and leptin/adiponectin ratio were also associated with metabolic syndrome (P<0.01). No relationship was found between metabolic syndrome and hsCRP. Adiponectin and adiponectin/HOMA-IR were associated with all the components of metabolic syndrome and they can be useful to identify patients with high risk of diabetes mellitus and cardiovascular disease.

Contribution of obesity as an effect regulator to an association between serum leptin and incident metabolic syndrome

BACKGROUND

We investigated whether serum leptin can be a predictor for incident cases of MetS in a population-based study.

METHODS

This is a prospective cohort study of 1590 adults aged between 40 and 70 years, who did not have MetS in 2005-2008 (at baseline) and 2008-2011 (follow-up). The baseline serum leptin concentrations were measured by radioimmunoassay.

RESULTS

During an average of 2.8 years of follow-up, 113 men (17.1%) and 148 women (15.9%) developed MetS. In multivariable adjusted models, the odds ratio of incident MetS when comparing the lowest to the highest quartiles of leptin levels was 3.17 in men and 2.79 in women; nevertheless, the significance disappeared after adjusting for the body mass index (BMI). In subsidiary analyses by BMI, logistic regression analysis showed that subjects with the highest tertile of serum leptin level were 3.04 and 2.12 times more likely to have MetS than those with the lowest tertile in lean subjects (OR 3.04; 95% CI 1.44-6.41; p = .004 in men vs. OR 2.12; 95% CI 1.06-4.25; p = .036 in women, respectively).

CONCLUSIONS

Obesity is an effect regulator, which can predict an association between increased serum leptin level and the incidence of MetS in lean subjects.

Relationships between adiponectin levels, the metabolic syndrome, and type 2 diabetes: a literature review

Elevated hepatic glucose production, impaired insulin secretion, and insulin resistance - abnormalities of glucose metabolism typically found in subjects with obesity - are major factors underlying the pathogenesis of type 2 diabetes (DM2) and the metabolic syndrome (MS). Adiponectin is a major regulator of glucose and lipid homeostasis via its insulin-sensitizing properties, and lower levels seems to be associated with the development of DM2 and MS. The purpose of this review is to clarify the mechanisms whereby adiponectin relates to the development of DM2 and MS and the association between polymorphisms of the adiponectin gene, circulating levels of the hormone, and its relationships with DM2. In addition, the impact of dietary lipids in the circulating levels of adiponectin will be addressed. According to the literature, circulating adiponectin levels seem to decrease as the number of MS components increases. Lower adiponectin concentrations are associated with higher intra-abdominal fat content. Therefore, adiponectin could link intra-abdominal fat with insulin resistance and development of MS. Therapeutic strategies that target the MS and its components, such as lifestyle modification through physical activity and weight loss, have been shown to increase adiponectin concentrations. Possible roles of diets containing either low or high amounts of fat, or different types of fat, have been analyzed in several studies, with heterogeneous results. Supplementation with n-3 PUFA modestly increases adiponectin levels, whereas conjugated linoleic acid supplementation appears to reduce concentrations when compared with unsaturated fatty acid supplementation used as an active placebo.

Hypoadiponectemia is associated with metabolic syndrome in patients with type 2 diabetes

Adipose tissue-expressed adiponectin levels are inversely related to the degree of adiposity, and a reduction in adiponectin serum levels is accompanied by insulin resistance. The aim of this study was to evaluate the relationship between serum adiponectin concentration and metabolic syndrome (MetS) in patients with type 2 diabetes mellitus (DM). Fasting blood samples were obtained from 150 volunteers with type 2 DM. MetS and its components were defined according to diagnostic criteria from the International Diabetes Federation. Serum adiponectin concentrations were measured using a commercially available enzyme-linked immunosorbent assay. Among the 150 patients with type 2 DM, 102 (68.0%) had MetS. Female gender (P = 0.007), hypertension (P = 0.005), systolic blood pressure (P < 0.001), diastolic blood pressure (DBP, P < 0.001), waist circumference (P < 0.001), body weight (P < 0.001), body mass index (BMI, P < 0.001), fasting glucose (P = 0.035), triglyceride (TG) level (P < 0.001), glycated hemoglobin level (HbA1c, P = 0.020), insulin level (P < 0.001), and homeostasis model assessment of insulin resistance (HOMA-IR, P < 0.001) were higher in DM patients who had MetS, whereas high-density lipoprotein cholesterol (HDL-C) concentrations (P < 0.001) and adiponectin levels (P < 0.001) were lower. Univariate linear analysis revealed that logarithmically transformed age (log-age, r = 0.279; P = 0.001) and HDL-C (r = 0.246; P = 0.002) positively correlated, whereas height (r = -0.183; P = 0.025), body weight (r = -0.282; P < 0.001), BMI (r = -0.237; P = 0.004), waist circumference (r = -0.249; P = 0.002), DBP (r = 0.252; P = 0.002), log-TG (r = 0.255; P = 0.002), log-insulin (r = -0.298; P < 0.001), and log-HOMA-IR (r = 0.288; P < 0.001) negatively correlated with serum adiponectin levels in patients with type 2 DM. Multivariate forward stepwise linear regression analysis revealed that log-age (adjusted R² change = 0.069; P < 0.001) positively correlated, whereas log-insulin (adjusted R² change = 0.182; P = 0.002) and HDL-C (adjusted R² change = 0.037; P = 0.006) negatively correlated with serum adiponectin levels in patients with type 2 DM. This study showed that lower serum adiponectin levels were positively associated with MetS in patients with type 2 DM and significantly positively related to age but negatively related to serum insulin and HDL-C levels in these subjects.

Visceral Fat Area and Serum Adiponectin Level Predict the Development of Metabolic Syndrome in a Community-Based Asymptomatic Population

Background

Although it has been demonstrated that visceral adipose tissue content and serum levels of adiponectin are associated with metabolic syndrome, their predictive potential for the development of metabolic syndrome remains to be elucidated.

Methods

We studied 1,130 participants of the Seoul Metabolic Syndrome cohort. A total of 337 subjects without metabolic syndrome underwent the follow-up evaluation and finally analyzed. Visceral fat area (VFA) was measured using dual bioelectrical impedance analysis. We compared the 1-year incidence rate of metabolic syndrome among four different groups: Group 1 (high adiponectin level and low VFA), Group 2 (low adiponectin level and low VFA), Group 3 (high adiponectin level and high VFA) and Group 4 (low adiponectin level and high VFA).

Results

Median follow-up duration was 17 months. Cut-off points of adiponectin level and VFA for metabolic syndrome were 7.34 ng/ml and 84 cm² for men, and 12.55 and 58 cm² ng/ml for women, respectively. The incidence of metabolic syndrome was the highest in Group 4 (Group 1; 16.47%, Group 2; 22.08%, Group 3; 25%, and Group 4; 46.15%, p<0.001). Adjusted logistic regression analyses for metabolic syndrome prediction demonstrated that Group 4 exhibited the highest odds ratio compared with Group 1 (4.918 [2.05–11.795]), which was predominantly affected by waist circumference and serum triglyceride levels. Notably, triglyceride/high-density lipoprotein cholesterol (TG/HDL) ratio was significantly higher in Group 4 (p = 0.017).

Conclusion

Incidence rate of metabolic syndrome was the highest in subjects with low serum adiponectin levels and high visceral fat area. Higher TG/HDL ratio in these subjects suggested insulin resistance may contribute to the development of metabolic syndrome.

Metabolic and Body Composition Risk Factors Associated with Metabolic Syndrome in a Cohort of Women with a High Prevalence of Cardiometabolic Disease

Background

The aetiology of the metabolic syndrome and the inter-relationship between risk factors for this syndrome are poorly understood. The purpose of this investigation was to determine the risk factors for metabolic syndrome and their interactions in a cohort of women with a high prevalence of metabolic syndrome.

Materials and Methods

Abdominal and whole body composition (ultrasound and dual-energy X-ray absorptiometry), blood pressure, and cardiometabolic and demographic factors were measured in a cross-sectional study of 702 black African women from Soweto, Johannesburg. Data was analysed using multivariate logistic regression.

Results

Metabolic syndrome was present in 49.6% of the study cohort. Logistic regression analysis demonstrated that adiponectin (odds ratio [95% CIs]: 0.84 [0.77, 0.92], p<0.0005) and abdominal subcutaneous fat (0.56 [0.39, 0.79], p = 0.001) reduced metabolic syndrome risk whilst insulin resistance (1.31 [1.16, 1.48], p<0.0005) and trunk fat-free soft-tissue mass (1.34 [1.10, 1.61], p = 0.002) increased risk. Within this group of risk factors, the relationship of adiponectin with metabolic syndrome risk, when analysed across adiponectin hexiles, was the least affected by adjustment for the other risk factors.

Conclusions

Adiponectin has a significant protective role against metabolic syndrome and is independent of other risk factors. The protective and possible augmentive effects of abdominal subcutaneous fat and lean trunk mass, respectively on metabolic syndrome risk demonstrate the existence of novel interactions between body composition and cardiometabolic disease.

Reduced circulating adiponectin levels are associated with the metabolic syndrome independently of obesity, lipid indices and serum insulin levels: a cross-sectional study

BACKGROUND

Given the increasing rate of overweight and the burden of metabolic syndrome (MetS) on cardiovascular disease development, better understanding of the syndrome is of great importance. Therefore, the objectives were to examine whether interleukin-6 (IL-6) and adiponectin are associated with MetS, and whether this association is mediated by components of the MetS.

METHODS

During 2011-2012, 284 individuals (159 men, 53 ± 9 years, 125 women 52 ± 9 years) without cardiovascular disease, type 1 diabetes mellitus, high-grade inflammatory disease, living in the greater Athens area, Greece, participated in clinical examination. Adiponectin and IL-6 were measured in fasting plasma samples. MetS was defined according to the International Diabetes Federation (IDF) and the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) criteria.

RESULTS

MetS was present in 37 % (IDF) and 33 % (AHA/NHLBI) of the study population (P < 0.001). Adiponectin was inversely associated with MetS (odds ratio, 95 % confidence interval: 0.829, 0.762- 0.902 for MetS-IDF, and 0.840, 0.772- 0.914 for MetS-AHA/NHLBI). Body mass index (BMI), waist circumference, high density lipoprotein (HDL)-cholesterol, triglyceride and insulin concentration mediated the association between adiponectin and MetS-IDF (z-test, standard error, P-value: 2.898, 0.012, 0.004, for BMI; 2.732, 0.012, 0.006 for waist circumference; 2.388, 0.011, 0.017 for HDL-cholesterol; 2.163, 0.010, 0.031 for triglyceride; 2.539,  0.010,  0.011 for insulin). Similarly, BMI, waist circumference, HDL-cholesterol and insulin concentration mediated the association between adiponectin and MetS-AHA/NHLBI (z-test, standard error, P-value: 2.633, 0.011, 0.008 for BMI; 2.441, 0.011, 0.015 for waist circumference; 1.980, 0.010, 0.048 for HDL-cholesterol; 2.225, 0.009, 0.026 for insulin). However, adiponectin remained significantly associated with MetS. IL-6 was not significantly associated with MetS.

CONCLUSION

MetS components, in particular obesity and lipid indices, as well as serum insulin levels, mediate the association between adiponectin and MetS as defined by both the IDF and AHA/NHLBI criteria.

Incremental Predictive Value of Serum AST-to-ALT Ratio for Incident Metabolic Syndrome: The ARIRANG Study

Aims

The ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) is of great interest as a possible novel marker of metabolic syndrome. However, longitudinal studies emphasizing the incremental predictive value of the AST-to-ALT ratio in diagnosing individuals at higher risk of developing metabolic syndrome are very scarce. Therefore, our study aimed to evaluate the AST-to-ALT ratio as an incremental predictor of new onset metabolic syndrome in a population-based cohort study.

Material and Methods

The population-based cohort study included 2276 adults (903 men and 1373 women) aged 40–70 years, who participated from 2005–2008 (baseline) without metabolic syndrome and were followed up from 2008–2011. Metabolic syndrome was defined according to the harmonized definition of metabolic syndrome. Serum concentrations of AST and ALT were determined by enzymatic methods.

Results

During an average follow-up period of 2.6-years, 395 individuals (17.4%) developed metabolic syndrome. In a multivariable adjusted model, the odds ratio (95% confidence interval) for new onset of metabolic syndrome, comparing the fourth quartile to the first quartile of the AST-to-ALT ratio, was 0.598 (0.422–0.853). The AST-to-ALT ratio also improved the area under the receiver operating characteristic curve (AUC) for predicting new cases of metabolic syndrome (0.715 vs. 0.732, P = 0.004). The net reclassification improvement of prediction models including the AST-to-ALT ratio was 0.23 (95% CI: 0.124–0.337, P<0.001), and the integrated discrimination improvement was 0.0094 (95% CI: 0.0046–0.0143, P<0.001).

Conclusions

The AST-to-ALT ratio independently predicted the future development of metabolic syndrome and had incremental predictive value for incident metabolic syndrome.

Fatty liver index as a simple predictor of incident diabetes from the KoGES-ARIRANG study

The fatty liver index (FLI), calculated from serum triglyceride, body mass index, waist circumference, and gamma-glutamyltransferase, is considered a surrogate marker of nonalcoholic fatty liver disease (NAFLD). We investigated whether FLI predicts the development of diabetes mellitus (DM) and assessed the predictive ability of FLI for new onset of DM in a prospective population-based cohort study.We analyzed a total of 2784 adults (944 men and 1840 women) aged 40 to 70 years without DM at baseline. Participants were classified according to FLI values into 3 groups: FLI < 30, no NAFLD; 30 ≤ FLI ≤ 59, intermediate NAFLD; and FLI ≥ 60, participants with NAFLD. The area under the receiver-operating characteristic curve (AUC), net reclassification improvement (NRI), and integrated discrimination improvement (IDI) were calculated to determine whether FLI improved DM risk prediction.During a mean of 2.6 years follow-up, 88 (3.16%) participants developed DM. The odds ratio analyzed from multivariable-adjusted models (95% confidence interval [CI]) for new onset of DM increased in a continuous manner with increased FLI (<30 vs 30-59 vs ≥60 = 1 vs 1.87 [95% CI 1.05-3.33] vs 2.84 [95% CI 1.4-5.75], respectively). The AUC significantly increased when FLI was added to the conventional DM prediction model (0.835, 95% CI: 0.789-0.881, P = 0.0289 vs traditional DM prediction model). The category-free NRI was 0.417 (95% CI: 0.199-0.635) and the IDI was 0.015 (95% CI: 0.003-0.026) for overall study participants.We found that FLI, a surrogate marker of hepatic steatosis, resulted in significant improvement in DM risk prediction. Our finding suggests that FLI may have clinical and prognostic information for incident DM among the Korean adult population.

Biomarkers of Metabolic Syndrome: Biochemical Background and Clinical Significance

Biomarkers of the metabolic syndrome are divided into four subgroups. Although dividing them in groups has some limitations, it can be used to draw some conclusions. In a first part, the dyslipidemias and markers of oxidative stress are discussed, while inflammatory markers and cardiometabolic biomarkers are reviewed in a second part. For most of them, the biochemical background and clinical significance are discussed, although here also a well-cut separation cannot always be made. Altered levels cannot always be claimed as the cause, risk, or consequence of the syndrome. Several factors are interrelated to each other and act in a concerted, antagonistic, synergistic, or modulating way. Most important conclusions are summarized at the end of every reviewed subgroup. Genetic biomarkers or influences of various food components on concentration levels are not included in this review article.

Association of Metabolic Syndrome with the Adiponectin to Homeostasis Model Assessment of Insulin Resistance Ratio

This study aimed at determining whether the adiponectin to HOMA-IR (A/H) ratio is associated with MetS and MetS components and comparing the diagnostic efficacy of adiponectin, HOMA-IR, and the A/H ratio in healthy, middle-aged participants. MetS was assessed in 1628 Kazakh participants (men, 768; women, 860). The associations between adiponectin, HOMA-IR, and the A/H ratio with the components of MetS and MetS were examined using logistic regression analysis and receiver operating characteristic (ROC) curves. Our results show that A/H ratio may be a better diagnostic marker for MetS than either HOMA-IR or adiponectin alone, and it may serve as an important biomarker to determine an increased risk for MetS in healthy middle-aged population.

A prospective study of serum adiponectin and regression of metabolic syndrome: The ARIRANG study

Increased serum adiponectin levels may play a protective role in metabolic syndrome. However, few prospective studies have examined the effect of serum adiponectin in the improvement of metabolic components in subjects with metabolic syndrome. We investigated the association of serum adiponectin levels with the regression of metabolic syndrome in a population-based longitudinal study. A total of 1308 adults (575 men and 733 women) with metabolic syndrome at baseline were examined and followed. Baseline serum adiponectin concentrations were measured by radioimmunoassay. During an average of 2.6 years of follow-up, metabolic syndrome had disappeared in 184 men (29.8%) and 235 women (32.1%). In multivariable adjusted models, the odds ratio (95% confidence interval) for regression of metabolic syndrome comparing the highest to the lowest quartiles of adiponectin levels was 0.93 (0.56-1.53) in men and 2.48 (1.54-4.01) in women. Increased serum adiponectin is a predictor for the regression of metabolic syndrome in women. Adiponectin may have potential therapeutic applications in metabolic disease.

Addition of N-terminal pro-B-type natriuretic peptide levels to electrocardiography criteria for detection of left ventricular hypertrophy: the ARIRANG study

The utility of electrocardiography (ECG) in screening for left ventricular hypertrophy (LVH) in general populations is limited mainly because its low sensitivity. B-type natriuretic peptide (BNP) is released due to the remodeling processes of LVH and could improve the diagnostic accuracy for the ECG criteria for LVH. We hypothesized that addition of BNP levels to ECG criteria could aid LVH detection compared with ECG alone in a general population. We enrolled consecutive 343 subjects from a community-based cohort. LVH was defined as LV mass index > 95 g/m(2) for females and > 115 g/m(2) for males according to echocardiography. The area under the receiver operator characteristic (ROC) curve to detect LVH was 0.55 (95% confidence interval [CI], 0.50-0.61) in Sokolow-Lyon criteria and 0.53 (0.47-0.59) in the Cornell voltage criteria. After addition of N-terminal-proBNP levels to the model, the corresponding areas under the ROC were 0.63 (0.58-0.69) and 0.64 (0.59-0.69), respectively. P values for the comparison in areas under the ROC for models with and without N-terminal-proBNP levels were < 0.001. These data suggest that addition of N-terminal-proBNP levels to ECG criteria could significantly improve the diagnostic accuracy of LVH in general populations.

A prospective study of epicardial adipose tissue and incident metabolic syndrome: the ARIRANG study

Increased epicardial adipose tissue (EAT) may be closely associated with the development of metabolic abnormalities. We investigated whether EAT predicts the incident metabolic syndrome in a community-based, middle-aged population. The study subjects were comprised of 354 adults (134 men and 220 women) aged 40 to 70 yr without metabolic syndrome. Baseline EAT thickness, measured by echocardiography, was compared between subjects who developed new-onset metabolic syndrome at follow-up survey and those who did not. After an average of 2.2 yr of follow-up, 32 men (23.9%) and 37 women (16.8%) developed metabolic syndrome. Median EAT thickness at baseline was significantly higher in male subjects who developed metabolic syndrome than those who did not (1.52 mm vs 2.37 mm, P<0.001). The highest quartile of EAT thickness (≥2.55 mm) was associated with increased risk of progression to metabolic syndrome (Odds ratio [OR], 3.09; 95% confidence interval [CI], 1.11-8.66) after adjustment for age, smoking, alcohol intake, regular exercise, total energy intake, high sensitive C-reactive protein and homeostasis model assessment of insulin resistance in men. A significant association of EAT with incident metabolic syndrome was not seen in women (OR, 1.25; 95% CI, 0.54-2.90). In conclusion, increased EAT thickness is an independent predictor for incident metabolic syndrome in men.

Changes in daily leptin, ghrelin and adiponectin profiles following a diet with carbohydrates eaten at dinner in obese subjects

BACKGROUND AND AIMS

Our recently published randomised clinical trial evaluated the effect of a low-calorie diet with carbohydrates eaten at dinner. This dietary pattern led to lower hunger scores, and better anthropometric, biochemical and inflammatory outcomes compared to a standard low-calorie diet. In the same study, changes in diurnal secretion patterns of leptin, ghrelin and adiponectin were investigated.

METHODS AND RESULTS

Seventy-eight police officers (body mass index (BMI) > 30) were randomly allocated to experimental (carbohydrates at dinner) or control weight loss diets for 6 months. Sixty-three subjects finished the programme. On days 0, 7, 90 and 180 blood samples and hunger scores were collected every 4 h from 8:00 to 20:00. Hormonal profiles were available for 39. The dietary manipulation led to changes in daylight hormonal profiles in the experimental group. Leptin's secretion curve became convex, with a nadir later in the day (significant difference compared to baseline at morning and evening, p = 0.023, p = 0.021, respectively). Ghrelin's secretion curve became concave, peaking only in the evening hours. Adiponectin's curve was elevated only after the experimental diet (significant difference compared to baseline at afternoon, p = 0.044).

CONCLUSIONS

We propose that a low-calorie diet with carbohydrates eaten at dinner can modulate daytime hormonal profiles. Taken together with our earlier results, we believe this diet regime may prevent mid-day hunger, better support weight loss and improve metabolic outcomes compared to conventional weight loss diets. The trial is registered at controlled-trials.com, ISRCTN37829376, December 2009.

Prospective study of serum adiponectin and incident metabolic syndrome: the ARIRANG study

OBJECTIVE

Increased adiponectin levels may play a protective role in the development of metabolic abnormalities, but prospective studies of the predictive value of serum adiponectin to identify individuals at high risk of new-onset metabolic syndrome are lacking. We investigated whether serum adiponectin predicts incident cases of the metabolic syndrome in a population-based longitudinal study.

RESEARCH DESIGN AND METHODS

A prospective cohort study was conducted of 2,044 adults (831 men and 1,213 women) aged 40-70 years without metabolic syndrome examined in 2005-2008 (baseline) and 2008-2011 (follow-up). Baseline serum adiponectin concentrations were measured by radioimmunoassay.

RESULTS

During an average of 2.6 years of follow-up, 153 men (18.4%) and 199 women (16.4%) developed metabolic syndrome. In multivariable-adjusted models, the odds ratio for incident metabolic syndrome comparing the highest with the lowest quartiles of adiponectin levels was 0.25 (95% CI 0.14-0.47) in men and 0.45 (0.28-0.74) in women. While serum adiponectin did not improve the area under the ROC curve for predicting new-onset metabolic syndrome based on information from metabolic syndrome components, the net reclassification improvement and the integrated discrimination improvement of prediction models including adiponectin were significantly higher compared with those of models not including adiponectin among men, with a significant difference between men and women (P = 0.001).

CONCLUSIONS

Increased adiponectin is an independent protective factor for incident metabolic syndrome in men and women, and it may have a clinical role in predicting new-onset metabolic syndrome among men.

A comprehensive analysis of adiponectin QTLs using SNP association, SNP cis-effects on peripheral blood gene expression and gene expression correlation identified novel metabolic syndrome (MetS) genes with potential role in carcinogenesis and systemic inflammation

BACKGROUND

Metabolic syndrome (MetS) is an aberration associated with increased risk for cancer and inflammation. Adiponectin, an adipocyte-produced abundant protein hormone, has countering effect on the diabetogenic and atherogenic components of MetS. Plasma levels of adiponectin are negatively correlated with onset of cancer and cancer patient mortality. We previously performed microsatellite linkage analyses using adiponectin as a surrogate marker and revealed two QTLs on chr5 (5p14) and chr14 (14q13).

METHODS

Using individuals from 85 extended families that contributed to the linkage and who were measured for 42 clinical and biologic MetS phenotypes, we tested QTL-based SNP associations, peripheral white blood cell (PWBC) gene expression, and the effects of cis-acting SNPs on gene expression to discover genomic elements that could affect the pathophysiology and complications of MetS.

RESULTS

Adiponectin levels were found to be highly intercorrelated phenotypically with the majority of MetS traits. QTL-specific haplotype-tagging SNPs associated with MetS phenotypes were annotated to 14 genes whose function could influence MetS biology as well as oncogenesis or inflammation. These were mechanistically categorized into four groups: cell-cell adhesion and mobility, signal transduction, transcription and protein sorting. Four genes were highly prioritized: cadherin 18 (CDH18), myosin X (MYO10), anchor protein 6 of AMPK (AKAP6), and neuronal PAS domain protein 3 (NPAS3). PWBC expression was detectable only for the following genes with multi-organ or with multi-function properties: NPAS3, MARCH6, MYO10 and FBXL7. Strong evidence of cis-effects on the expression of MYO10 in PWBC was found with SNPs clustered near the gene's transcription start site. MYO10 expression in PWBC was marginally correlated with body composition (p = 0.065) and adipokine levels in the periphery (p = 0.064). Variants of genes AKAP6, NPAS3, MARCH6 and FBXL7 have been previously reported to be associated with insulin resistance, inflammatory markers or adiposity studies using genome-wide approaches whereas associations of CDH18 and MYO10 with MetS traits have not been reported before.

CONCLUSIONS

Adiponectin QTLs-based SNP association and mRNA expression identified genes that could mediate the association between MetS and cancer or inflammation.

Association of genetic variants in the adiponectin gene with metabolic syndrome: a case-control study and a systematic meta-analysis in the Chinese population

Background

The prevalence of metabolic syndrome has been rising worldwide, including in China, but knowledge on specific genetic determinants of metabolic syndrome is very limited. A number of studies have reported that polymorphisms in the ADIPOQ gene are associated with metabolic syndrome in Chinese Han populations. However, data is still conflicting. The objective of this study was to examine the associations of the adiponectin genetic variants with metabolic syndrome by a case-control study and meta-analyses in Chinese.

Methods

We first investigated the association of ADIPOQ rs2241766 (+45T>G in exon 2), rs266729 (−11377C>G in promoter) and rs1501299 (+276G>T in intron 2) polymorphisms with metabolic syndrome in a Hubei Han Chinese population with 322 metabolic syndrome patients and 161 normal controls recruited from the Yichang, Hubei. Then we comprehensively reviewed the association between ADIPOQ rs2241766/rs266729/rs1501299 and metabolic syndrome in the Chinese populations via a meta-analysis. The strength of association was assessed by odds ratios (ORs) with 95% confidence intervals (CI).

Results

The G allele frequency of rs2241766 in metabolic syndrome patients was significantly higher than those of controls group (29.8% vs 23.3%, OR = 1.40, P = 0.033). The logistic regression analysis adjusted by gender and age showed a nominally significant association for rs2241766 GG+GT genotype (P = 0.065, OR = 1.55) and rs1501299 GG genotype in recessive model (OR = 1.54, P = 0.066). However, no association was observed for rs266729 in our sample. We identified thirteen studies for rs2241766 (2,684 metabolic syndrome patients and 2,864 controls), three studies for rs266729, and eleven studies for rs1501299 (2,889 metabolic syndrome patients and 3,304 controls) in Chinese. Meta-analysis indicated significant associations for the rs2241766 G allele (OR = 1.14, 95%CI = 1.05–1.24, P = 0.003), rs266729 GG+GT genotypes (OR = 0.80, 95%CI = 0.68–0.92, P = 0.003) and rs1501299 GG+TG genotypes (OR = 1.42, 95%CI 1.16–1.75, P = 0.001).

Conclusions

Our results demonstrated ADIPOQ as a pleiotropic locus for metabolic syndrome and its components in the Han Chinese population.

Adiponectin and metabolic syndrome in a Tunisian population

The aim of this study was to investigate the relationship between the adiponectin levels and various characteristics of the metabolic syndrome (MS) in a sample of the Tunisian population. Three hundred and fifty-four individuals were included in this study. Body mass index, blood pressure, HDL-cholesterol, triglycerides, glucose, insulin, and adiponectin concentrations were measured. Insulin resistance was assessed by homeostasis model assessment of insulin resistance (HOMA-IR). MS was identified with the NCEP-ATP III criteria. Subjects with MS showed significantly lower adiponectin levels compared to those without MS. For both genders, the prevalence and the number of MS components increased significantly as the adiponectin concentrations decreased. Subjects with the lowest adiponectin quartile had an increased risk of MS adjusted for age, gender, and HOMA-IR. Our findings suggest that hypoadiponectinemia is strongly associated with the risk of MS independent of insulin resistance.

Plasma adiponectin concentration and its association with metabolic syndrome in patients with heart failure

PURPOSE

Plasma adiponectin concentrations are inversely related with metabolic syndrome (MetS), and MetS is associated with increased risk for heart failure (HF). However, the relationship between adiponectin and MetS in HF remains undetermined. Therefore, we tested whether MetS was associated with the degree of plasma adiponectin concentrations in HF patients.

MATERIALS AND METHODS

One hundred twenty eight ambulatory HF patients with left ventricular ejection fraction of <50% (80 males, 61.8 ± 11.9 years old) were enrolled for this cross-sectional study. Echocardiographic measurements were performed, and plasma concentrations of adiponectin, lipoproteins, apolipoproteins (apoB, apoA1) and high sensitive C-reactive protein (hsCRP) were measured.

RESULTS

Adiponectin concentrations in HF patients with MetS (n=43) were significantly lower than those without MetS (n=85) (9.7 ± 7.0 vs. 15.8 ± 10.9 μg/mL, p=0.001). Higher concentrations of apoB (p=0.017), apoB/A1 ratio (p<0.001), blood urea nitrogen (p=0.034), creatinine (p=0.003), and fasting insulin (p=0.004) were observed in HF patients with MetS compared with those without MetS. In HF patients with MetS, adiponectin concentrations were negatively correlated with hsCRP (r=-0.388, p=0.015) and positively correlated with the ratio of early mitral inflow velocity to early diastolic mitral annular velocity, E/E' (r=0.399, p=0.015). There was a significant trend towards decreased adiponectin concentrations with an increasing number of components of MetS (p for trend=0.012).

CONCLUSION

Our study demonstrated that adiponectin concentrations decreased in HF patients with MetS, and that relationship between adiponectin, inflammation and abnormal diastolic function, possibly leading to the progression of HF.