Hyperleptinemia as a component of a metabolic syndrome of cardiovascular risk

Comprehensive prognostic effects of systemic inflammation and Insulin resistance in women with breast cancer with different BMI: a prospective multicenter cohort

To investigate the prognostic value of systemic inflammation and insulin resistance in women with breast cancer with different body mass index (BMI). This multicenter, prospective study included 514 women with breast cancer. Multivariate survival analysis showed that patients with high C-reactive protein (CRP), high CRP to albumin ratio (CAR), high lymphocyte to CRP ratio (LCR), high low-density lipoprotein cholesterol to high-density lipoprotein cholesterol ratio (LHR), and high triglyceride to high-density lipoprotein cholesterol ratio (TG/HDL-c) were significantly associated with worse prognosis. The mortality rate of patients with both high CAR and high LHR or both low LCR and high LHR were 3.91-fold or 3.89-fold higher than patients with both low CAR and low LHR or both high LCR and low LHR, respectively. Furthermore, the combination of LCR and LHR significantly predicted survival in patients within the high BMI group. The CRP, CAR, LCR, LHR, and TG/HDL-c were associated with poor survival in women with breast cancer. The combination of CAR and LHR or LCR and LHR could better predict the prognostic outcomes of women with breast cancer, while the combination of LCR and LHR could better predict the prognosis of those patients with overweight or obese patients.

Role of inflammation in diabetic cardiomyopathy

The prevalence of type 2 diabetes (T2D) has reached a pandemic scale. Systemic chronic inflammation dominates the diabetes pathophysiology and has been implicated as a causal factor for the development of vascular complications. Heart failure (HF) is regarded as the most common cardiovascular complication of T2D and the diabetic diagnosis is an independent risk factor for HF development. Key molecular mechanisms pivotal to the development of diabetic cardiomyopathy include the NF-κB pathway and renin-angiotensin-aldosterone system, in addition to advanced glycation end product accumulation and inflammatory interleukin overexpression. Chronic myocardial inflammation in T2D mediates structural and metabolic changes, including cardiomyocyte apoptosis, impaired calcium handling, myocardial hypertrophy and fibrosis, all of which contribute to the diabetic HF phenotype. Advanced cardiovascular magnetic resonance imaging (CMR) has emerged as a gold standard non-invasive tool to delineate myocardial structural and functional changes. This review explores the role of chronic inflammation in diabetic cardiomyopathy and the ability of CMR to identify inflammation-mediated myocardial sequelae, such as oedema and diffuse fibrosis.

Inflammatory Biomarkers and Components of Metabolic Syndrome in Adolescents: a Systematic Review

Metabolic syndrome (MetS) has been prevalent among adolescents. The association between the concentration of inflammatory markers and the individual components of the metabolic syndrome indicates that inflammation, when there is no recent or ongoing disease, mediated by an inflammatory process, is an event that may precede the development of metabolic disorders in teenagers. The objective of this study is to verify the association of inflammatory biomarkers with the components of metabolic syndrome in adolescents. From a search of 3 databases, 13 articles met the study inclusion criteria. Two investigators independently extracted data from included studies. The evaluated inflammatory biomarkers are related to the components of MetS (insulin resistance, central and visceral obesity, arterial hypertension, dyslipidemia), which may increase the risk of developing the syndrome in adolescents. The results of this review are of clinical relevance, since the evaluation of inflammatory biomarkers in the presence of metabolic alterations can help to identify the risk factors that lead to the progression of MetS in adolescents.

Leptin, adiponectin, and their ratio as markers of insulin resistance and cardiometabolic risk in childhood obesity

BACKGROUND

It is imperative to develop markers for risk stratification and detection of cardiometabolic comorbidities in children with obesity. The adipokines leptin and adiponectin are both involved in fat mass regulation and the development of obesity-related disorders; furthermore, their ratio (leptin/adiponectin ratio) is suggested to be associated with insulin resistance and cardiometabolic risk.

OBJECTIVE

To evaluate associations between fasting serum concentrations of the adipokines (total leptin and adiponectin as well as the L/A ratio) and cardiometabolic comorbidities in children with overweight/obesity.

METHODS

A total of 2258 children with overweight/obesity or normal weight aged 6 to 18 years were studied. Differences in anthropometrics and adipokine concentrations were tested using Wilcoxon rank-sum test. Associations between the adipokines and cardiometabolic risk were tested using Spearman's correlation and logistic regression, adjusted for age and body mass index SD score (BMI-SDS).

RESULTS

Compared to normal weight children; children with overweight/obesity exhibited higher leptin concentrations, lower adiponectin concentrations, and higher L/A ratios. After adjusting for age and degree of obesity, girls with overweight/obesity in the upper quartile range for the L/A ratio, when compared with girls in the lower quartile range, were more likely to have insulin resistance (odds ratio [OR]: 7.78 [95% confidence interval [CI], 3.78-16.65]), dysglycemia (OR: 3.08 [95% CI, 1.35-7.31]), and dyslipidemia (OR: 2.53 [95% CI, 1.18-5.59]); while boys were more likely to have insulin resistance (OR: 4.45 [95% CI, 2.03-10.10]).

CONCLUSIONS

Independent of the degree of obesity, leptin, adiponectin, and the L/A ratio were associated with insulin resistance and other cardiometabolic comorbidities in children with overweight/obesity, but the L/A ratio exhibited stronger associations than the respective adipokines.

The association of obesity and serum leptin levels with complete blood count and some serum biochemical parameters in Iranian overweight and obese individuals

Background: Obesity has been suggested to be well correlated with altered levels of complete blood count (CBC) parameters. In this study, the relationship of body mass index (BMI) and circulating leptin levels with CBC among obese and overweight adults was examined. Methods: CBC and biochemical parameters, WBC and hematological profiles, leptin levels, related factors to liver, and kidney and lipid profiles were measured among 184 obese and overweight people aged 18-60 years. Statistical analysis was performed using SPSS software. To assess the normality of data, the Kolmogorov-Smirnov test was used. Logarithmic transformation was performed for some variables with non-normal distribution. The association between 2 quantitative variables was measured using bivariate correlation (Pearson or Spearman). Pearson correlations and multiple regression analysis were performed to assess the correlation between variables. Simple and multiple regression analyses were performed to predict some variables. P- value <0.05 was considered significant. Results: Hematocrit, insulin, fasting blood sugar, uric acid, TG, LDL-C, VLDL-C, and ALT were positively correlated with BMI (p=0.041, r=0.149 for hematocrit; p≤0.001, r=0.520 for insulin; p≤0.001, r=0.363 for FBS; p≤0.001, r=0.309 for uric acid; p=0.015, r=0.189 for TG; p=0.030, r=161 for LDL-C; p=0.019, r=0.181 for VLDL-C; p≤0.001, r=0.299 for ALT), whereas urea and HDL-C were negatively correlated with BMI (p≤0.001, r=-0.368 for urea; p≤0.001, r=-0.297 for HDL-C). Moreover, LDL-C and insulin were positively correlated with leptin (P = 0.011, r = 0.194 for LDL-C, P = 0.013, r = 0.114 for insulin) and hematocrit, urea, creatinine, TG and VLDL-C were negatively correlated with leptin (p=0.040, r=-0.162 for hematocrit; p≤0.001, r=-0.305 for urea; p=0.007, r=-0.219 for creatinine; p=0.025, r=0.188 for TG; p=0.007, r=-0.218 for VLDL-C). Our analysis showed that white blood cell was positively correlated with leptin (β=17.36, p=0.048). Also, other CBC parameters had no significant correlations with BMI and leptin. Conclusion: According to the findings of this study, BMI had a negative association with urea and HDL-C, while BMI had a positive association with insulin, hematocrit, FBS, uric acid, TG, VLDL-C, LDL-C, and ALT. Furthermore, leptin had a negative association with hematocrit, creatinine, and urea, TG, VLDL-C and a positive association with LDL-C and insulin among the participants of this study.

Anthocyanins in the Management of Metabolic Syndrome: A Pharmacological and Biopharmaceutical Review

The term "metabolic syndrome" (MetS) refers to a combination of diabetes, high blood pressure, and obesity. The origin of MetS includes a combination of multiple factors, such as sedentary lifestyle, unhealthy diet choice, and genetic factors. MetS is highly prevalent and adversely affects the general population by elevating risk of cardiovascular complications, organ failure, and much other pathology associated with late-stage diabetes. Anthocyanins (ANTs) are health-promoting bioactive compounds belonging to the flavonoids subclass of polyphenols. Numerous studies have reported the potential therapeutic benefits on MetS syndrome and diabetes from fruits rich in ANTs. This review summarizes the role of several dietary ANTs on preventing and managing MetS as well as the pharmacological mechanisms and biopharmaceutical features of their action. We also discuss potential nanoformulation and encapsulation approaches that may enhance the bioefficacy of ANTs in MetS. Experiments have demonstrated that ANTs may attenuate the symptoms of MetS via improving insulin resistance, impaired glucose tolerance, dyslipidaemia, cholesterol levels, hypertension, blood glucose, protecting β cells, and preventing free radical production. In brief, the intake of ANT-rich supplements should be considered due to their plausible ability for prevention and management of MetS. Additionally, randomized double-blind clinical trials are obligatory for evaluating the bioefficacy and pharmacological mechanisms of ANTs and their pharmaceutical formulations in patients with MetS.

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.

Leptin-induced cardiomyocyte hypertrophy is associated with enhanced mitochondrial fission

Cardiac pathology including hypertrophy has been associated with an imbalance between mitochondrial fission and fusion. Generally, well-balanced mitochondrial fission and fusion are essential for proper functions of mitochondria. Leptin is a 16-kDa appetite-suppressing protein which has been shown to induce cardiomyocyte hypertrophy. In the present study, we determined whether leptin can influence mitochondrial fission or fusion and whether this can be related to its hypertrophic effect. Cardiomyocytes treated for 24 h with 3.1 nM leptin (50 ng/ml), a concentration representing plasma levels in obese individuals, demonstrated an increase in surface area and a significant 1.6-fold increase in the expression of the β-myosin heavy chain. Mitochondrial staining with MitoTracker Green dye showed elongated structures in control cells with an average length of 4.5 µm. Leptin produced a time-dependent increase in mitochondrial fragmentation with decreasing mitochondrial length. The hypertrophic response to leptin was also associated with increased protein levels of the mitochondrial fission protein dynamin-related protein1 (Drp1) although gene expression of Drp1 was unaffected possibly suggesting post-translational modifications of Drp1. Indeed, leptin treatment was associated with decreased levels of phosphorylated Drp1 and increased translocation of Drp1 to the mitochondria thereby demonstrating a pro-fission effect of leptin. As calcineurin may dephosphorylate Drp1, we determined the effect of a calcineurin inhibitor, FK506, which prevented leptin-induced hypertrophy as well as mitochondrial fission and mitochondrial dysfunction. In conclusion, our data show that leptin-induced cardiomyocyte hypertrophy is associated with enhanced mitochondrial fission via a calcineurin-mediated pathway. The ability of leptin to stimulate mitochondrial fission may be important in understanding the role of this protein in cardiac pathology especially that related to mitochondrial dysfunction.

Relationship of serum leptin with some biochemical, anthropometric parameters and abdominal fat volumes as measured by magnetic resonance imaging

AIMS

To measure the level of leptin in volunteers and correlate it with several anthropometric, biochemical variables and abdominal fat volumes.

METHODS

The level of leptin was investigated in 167 disease-free volunteers. Serum levels of IL-6, adiponectin, and resistin, blood lipid profile (cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglyceride (TG) were determined. Waist circumference (WC) was measured using tape and magnetic resonance imaging (MRI) images.

RESULTS

All measured anthropometric (BMI, WC measured by tape and MRI) and biochemical variables (adiponectin, resistin, cholesterol, HDL, LDL and TG); and abdominal fats showed a significant (p<0.05) difference between participants with abnormal serum leptin levels and those with normal leptin levels. A higher percentage of participants with abnormal serum leptin were obese males while participants with normal leptin levels were either overweight or normal weight females. A significant (p <0.05) positive correlation was detected between serum leptin concentration and WC, BMI, subcutaneous fat, visceral fat, total abdominal fat, and resistin. A moderate association was found between serum leptin concentration and the inflammatory cytokine IL-6.

CONCLUSION

Abnormal serum leptin, was detected in obese male individuals which may be considered as an important indicator for the development of cardiovascular diseases and type 2 diabetes.

Leptin predicts short-term major adverse cardiac events in patients with coronary artery disease

INTRODUCTION

Leptin is an adipose tissue-derived hormone associated with cardiovascular risk factors. We examined whether leptin predicts major adverse cardiac events (MACE) in coronary artery disease (CAD) patients.

METHODS

Fasting plasma leptin levels were measured in 1327 male and 619 female CAD patients. The patients were followed up for two years. The primary endpoint (MACE) was the composite of a hospitalisation for congestive heart failure (CHF) or a cardiac death. The secondary endpoint was the composite of an acute coronary syndrome (ACS) or a stroke.

RESULTS

In regression analysis including established risk variables, high leptin levels were associated with a significantly increased risk of MACE (HR 3.37; 95%CI 1.64-6.90; p = 0.001) and ACS or stroke (HR 1.95; 95%CI 1.29-2.96; p = 0.002). Adding leptin to the risk model for MACE increased the C-index from 0.78 (95%CI 0.71-0.85) to 0.81 (0.74-0.88) and improved classification (NRI 0.36; 95%CI 0.13-0.60; p = 0.002) and discrimination of the patients (IDI 0.016; 95%CI 0.001-0.030; p = 0.031).

CONCLUSIONS

High plasma leptin levels predict short-term occurrence of CHF or cardiac death and ACS or stroke in patients with CAD independently of established risk factors. The possible harmful effects of leptin should be thoroughly investigated. Key messages Leptin is a peptide hormone secreted mainly by adipose tissue. It has been associated with several cardiovascular risk factors. High leptin levels predict the short-term occurrence of congestive heart failure or cardiac death and ACS or stroke in patients with CAD independently of established risk factors. The possible detrimental effects of leptin on the cardiovascular system should be thoroughly investigated.

Ovarian acyclicity in zoo African elephants (Loxodonta africana) is associated with high body condition scores and elevated serum insulin and leptin

The purpose of the present study was to determine whether excessive body fat and altered metabolic hormone concentrations in the circulation were associated with ovarian acyclicity in the world's largest land mammal, the African elephant. We compared body condition, glucose, insulin and leptin concentrations and the glucose-to-insulin ratio (G:I) between cycling (n=23; normal 14-16 week cycles based on serum progestagens for at least 2 years) and non-cycling (n=23; consistent baseline progestagen concentrations for at least 2 years) females. A validated body condition score (BCS) index (five-point scale; 1=thinnest, 5=fattest) was used to assess the degree of fatness of the study elephants. The mean BCS of non-cycling elephants was higher than that of their cycling counterparts. There were differences in concentrations of serum metabolic biomarkers, with non-cycling elephants in the BCS 5 category having higher leptin and insulin concentrations and a lower G:I ratio than cycling BCS 5 females. Using 'non-cycling' as the outcome variable in regression models, high BCS was a strong predictor of a non-cycling status. This study provides the first evidence that ovarian acyclicity in zoo African elephants is associated with body condition indicative of obesity, as well as elevated, perturbed biomarkers of metabolic status.

An observational study of haemostatic changes, leptin and soluble endoglin during pregnancy in women with different BMIs

Obesity increases the risk of venous thromboembolism (VTE) in pregnancy. The pathogenesis is hypothesized to be because of multiple factors including prothrombotic changes, but there has been minimal haemostatic research looking at the combined state of obesity and pregnancy. We aimed to determine whether variation in BMI in the third trimester of pregnancy was associated with prothrombotic changes. We recruited 110 women into four groups depending on their BMI at first antenatal appointment: normal, overweight, obese and morbidly obese. Women with increased risk of VTE, and/or receiving thromboprophylaxis, and/or more than 35 years and those in labour were excluded. Thromboelastography, platelet count, prothrombin time, activated partial thromboplastin time, fibrinogen, prothrombin fragment 1 + 2, free and total protein S, plasminogen activator inhibitor type 1, tissue plasminogen activator antigen, D-dimers, soluble endoglin and leptin levels were measured. There were no significant differences in haemostatic measures with changing BMI. There was a positive correlation between BMI and both platelet count (correlation coefficient r = 0.214, P = 0.036) and leptin (r = 0.435, P < 0.001), but only leptin had a significant association with BMI once adjusted for age, gestation and parity. Despite recruitment into the morbidly obese group being suboptimal, these findings suggest that in pregnancy, the increased risk of VTE seen in obese mothers is not mediated through increased prothrombotic changes, and thus the increased risk of VTE in obese pregnant women may be because of other mechanisms, for example endothelial dysfunction, inflammation and venous stasis.

Plasma Leptin in Patients at Intermediate to High Cardiovascular Risk With and Without Type 2 Diabetes Mellitus

BACKGROUND

A number of clinical studies have demonstrated that leptin concentrations are related to the metabolic disturbances that constitute the metabolic syndrome (MetS) and to diabetes mellitus (DM).

AIM

To investigate possible determinants of leptin concentrations in a sample of patients at high cardiovascular (CV) risk carrying two or more features of the MetS and to investigate if any difference exist between at risk patients with or without DM.

METHODS

Serum leptin concentrations were measured in 60 consecutive male patients affected by at least two CV risk factors which belong to the National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III) definition of MetS: 30 patients affected by type 2 DM (T2DM) and 30 nondiabetic patients (non-T2DM). Nineteen healthy subjects were included in the study as a control group (HC).

RESULTS

Leptin was significantly higher in patients carrying two or more features of the MetS compared with HC (P = 0.02). Stratifying MetS patients for DM, we found that leptin level was higher in non-T2DM patients (7.8 ng/ml), intermediate in T2DM (6.2 ng/ml), and lower in HC (4.6 ng/ml). In MetS patients, a positive correlation was found between leptin and waist, triglycerides, and number of MetS criteria. After stratification for T2DM, the correlations were still significant in the non-T2DM but not in the T2DM group.

CONCLUSIONS

In our sample of moderate-to-high-risk patients, leptin level is positively associated with waist circumference and triglycerides but only in non-T2DM patients. Our data suggest that diabetic subjects could modulate leptin production in a different way compared with patients carrying other MetS-related anomalies.

The Association of Serum Leptin with Mortality in Older Adults

Objective

Elevated levels of serum leptin are associated with increased adiposity and production of pro-inflammatory cytokines. Both cytokines and body adiposity have been shown to predict cardiovascular events and mortality. The primary objective of the present study is to explore the associations between serum leptin and all-cause mortality and mortality from cardiovascular disease (CVD) over a span of 10 years, controlling for body adiposity and proinflammatory cytokines.

Methods

The Health, Aging and Body Composition (Health ABC) study is a prospective cohort of 3,075 older adults aged 70 to 79 years. This analysis includes 2,919 men and women with complete serum leptin and vital status data. Data on all-cause mortality and incident cardiovascular events (including Coronary Heart Disease and Congestive Heart Failure) were collected over 10 years of follow-up (mean 8.4 years).

Results

Women with leptin in quartile 2 and 3 were at lower risk of all-cause mortality, and those with leptin in quartile 2 were at lower risk of mortality from CVD as compared to women with lowest leptin values when adjusted for age, race, site, years of education, alcohol use, smoking, and physical activity. When these associations were additionally adjusted for body fat, C-reactive protein and pro-inflammatory cytokines, women with leptin values in quartile 3 were at lower risk of all-cause mortality and women with leptin in quartile 2 and 3 were at lower risk of mortality from CVD than women with lowest leptin values. These associations were not significant among men after adjusting for body fat and cytokines.

Conclusions

The present study suggests that moderately elevated concentrations of serum leptin are independently associated with lower risk of all-cause mortality and CVD-related mortality among older women. Among men, serum leptin is not associated with reduced risk of all-cause and CVD mortality after controlling for body fat and cytokines.

Association between plasma leptin level and systemic inflammatory markers in patients with aggressive periodontitis

Background:

Increasing evidence supports an association between periodontitis and systemic diseases. Leptin is involved both in the energy metabolism and inflammatory processes and is suggested to be a link between periodontal infection and systemic health. The present study aimed to evaluate the peripheral leptin concentration in patients with aggressive periodontitis (AgP) and to explore the relationship between leptin and systemic inflammation.

Methods:

Ninety patients with AgP visiting the Clinic of the Periodontology Department, Peking University School and Hospital of Stomatology between July 2001 and May 2006, and 44 healthy controls (staff and student volunteers in the same institute) were recruited. Plasma levels of leptin and inflammatory cytokines including interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP) were measured by enzyme-linked immunosorbent assay. Correlation and multiple linear regression analysis were performed to analyze the association between plasma leptin level and other variables.

Results:

Plasma leptin level of AgP group was significantly higher than that of the control group (19.7 ± 4.4 ng/ml vs. 7.5 ± 1.3 ng/ml, P < 0.01). After controlling for age, gender, and body mass index, positive correlation was observed between plasma leptin concentration and log-transformed levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α and CRP), and the partial correlation coefficients ranged from 0.199 to 0.376 (P < 0.05). Log-transformed IL-1β and IL-6 levels entered the final regression model (standardized β were 0.422 and 0.461 respectively, P < 0.01).

Conclusions:

Elevated plasma leptin concentration may be associated with increased systemic levels of inflammatory markers in AgP patients.

The impact of long-term changes in metabolic status on cardiovascular biomarkers and microvascular endothelial function in middle-aged men: a 25-year prospective study

BACKGROUND

The aim of this analysis was to examine long-term effects of changes in metabolic status on microvascular endothelial function and cardiovascular diseases (CVD) biomarkers among physically active middle-aged men.

METHODS

Metabolically healthy men (n = 101, mean age 59.7 years), free of symptoms and treatment, have been prospectively observed for their lifestyle and CVD risk factors (observation period 24.7 years). At the latest follow-up (2011/2012) a set of CVD biomarkers was measured using enzyme-linked immunosorbent assay. Microvascular endothelial function was evaluated by means of the reactive hyperemia index (RHI) using Endo-PAT2000 system. At follow-up the participants were divided into metabolically healthy (0-1 metabolic parameters) and metabolically unhealthy (≥2 metabolic parameters) groups. Metabolic syndrome was defined according to the NCEP ATP III definition.

RESULTS

Traditional metabolic risk factors were significantly associated with hsCRP, ox-LDL, Il-6, leptin and adiponectin/leptin ratio. Reactive hyperemia index was negatively related to body mass (p < 0.01), waist circumference (p < 0.05), triglycerides (p < 0.01), TG/HDL ratio (p < 0.01), uric acid (p < 0.05), sICAM-1 (p < 0.05) and Il-6 (p < 0.05), and positively to HDL-C (p < 0.01) and leisure-time physical activity (p < 0.01). Men who maintained metabolically healthy status (n = 47) through the observation had significantly lower hsCRP and uric acid (p < 0.05), higher adiponectin/leptin ratio (p < 0.05), higher mean RHI and lower prevalence of endothelial dysfunction (p < 0.05) as compared to the metabolically unhealthy group (n = 54). Regular physical activity level was significantly higher among metabolically healthy individuals during the whole observation.

CONCLUSIONS

Even subtle changes in metabolic profile influence inflammatory biomarkers and microvascular endothelial function. Leptin, adiponectin/leptin ratio and hsCRP are significant predictors of metabolic profile. Interleukine-6 and sICAM-1 may be used as indicators of early endothelial dysfunction in asymptomatic men. High leisure-time physical activity level is an important contributor of metabolically healthy profile through middle adulthood.

MiR-93 Controls Adiposity via Inhibition of Sirt7 and Tbx3

Conquering obesity has become a major socioeconomic challenge. Here, we show that reduced expression of the miR-25-93-106b cluster, or miR-93 alone, increases fat mass and, subsequently, insulin resistance. Mechanistically, we discovered an intricate interplay between enhanced adipocyte precursor turnover and increased adipogenesis. First, miR-93 controls Tbx3, thereby limiting self-renewal in early adipocyte precursors. Second, miR-93 inhibits the metabolic target Sirt7, which we identified as a major driver of in vivo adipogenesis via induction of differentiation and maturation of early adipocyte precursors. Using mouse parabiosis, obesity in mir-25-93-106b(-/-) mice could be rescued by restoring levels of circulating miRNA and subsequent inhibition of Tbx3 and Sirt7. Downregulation of miR-93 also occurred in obese ob/ob mice, and this phenocopy of mir-25-93-106b(-/-) was partially reversible with injection of miR-93 mimics. Our data establish miR-93 as a negative regulator of adipogenesis and a potential therapeutic option for obesity and the metabolic syndrome.

Identification of Predictable Biomarkers in Conjunction to Framingham Risk Score to Predict the Risk for Cardiovascular disease (CVD) in Non Cardiac Subjects

INTRODUCTION

Although the cardiovascular disease (CVD) burden is rising in different countries, the morbidity and mortality rate is not reduced to much extent because of lack of application of the biomarkers for diagnosing CVD. Hence, we aimed to establish the predictable biomarkers in conjunction to framingham risk score in order to predict the risk for CVD in non cardiac patients.

MATERIALS AND METHODS

Three hundred subjects were screened for the study who came for the master health checkup. Out of them 50 patients were excluded as they were under medication. 23 patients were excluded due to various systemic diseases like fever and infection etc. The remaining of 227 patients with age range of 30-80 y was randomly selected for investigation. These subjects were divided into four different groups: Group I - controls with age range: 30-60 y (n=50) these subjects were free from all the systemic ailments and risk factors. Study groups comprised of Group II - (n=44) with age range: 30-40 y, Group III - (n=50) with age range: 41-50 y and Group IV - (n=83) with age range: 51-80 y. Patients with different risk factors without medication participated as study groups. Routine biochemical parameters were analysed using fully automated analyser and atherosclerotic biomarkers was analysed using ELISA kit. In addition to this, framingham risk scores was calculated in all the groups, for 30 y risk prognosis for CVD.

RESULTS

The atherosclerotic biomarkers such as E-selectin, Leptin, osteoprotegerin (OPG) and Ox-LDL were elevated among the study groups as compared to control group. Pearson correlation showed a significant association between the individual risk score (30 y framingham risk for CVD) of individuals, and the above biomarkers. The Receiver operating curve (ROC) analysis also showed a greater area under curve with higher sensitivity and specificity.

CONCLUSION

We conclude the application E-Selectin, leptin, OPG and Ox-LDL as biomarkers along with the framingham risk scores in prediction risk for CVD in the individuals with subclinical atherosclerosis. It is more reliable and predictable as compared to the individual biomarkers alone.

Hyperleptinemia May Protect From Cardio-Vascular Complications: A Small Georgian Study

BACKGROUND AND AIM: Leptin was assessed to play a coordinating role in obesity and its cardio-vascular complications, however the findings are conflicting and further clinical investigation is required. The aim of the present study was to evaluate the association of serum leptin with cardio-vascular risk factors in different body mass index and age groups.MATERIALS AND METHODS:  One hundred and forty nine female patients were enrolled in the study and divided into groups according to body mass index (BMI) and age. Following measurements were carried out: height, weight, BMI, waist circumference, blood pressure. Venous blood sample was obtained for plasma leptin, insulin, glucose and lipid profile analysis. Insulin resistance index was calculated for each patient. Body fat distribution was measured using Dual energy X-ray Absorbtiometry.RESULTS: The lowest leptin concentration was observed in overweight patients, the highest concentration was seen in obese patients. The difference between leptin levels were not observed in age groups. Leptin positively correlated with high density lipoprotein cholesterol levels in obese and elder patients.CONCLUSION: Leptin might act as a preventive measure for cardiovascular complications only in the presence of sufficient amount of fat mass. Further studies are warranted in order to support these results.

Short-term response of metabolic hormones to coronary artery bypass surgery

PURPOSE

To explore the response pattern of plasma adipokine and ghrelin levels to coronary artery bypass graft (CABG) surgery in patients with (on-pump) and without (off-pump) cardiopulmonary bypass (CPB).

MATERIAL/METHODS

Sixteen consecutive patients (age: 62 ± 10 years, male: 10) with obstructive coronary artery disease (CAD) who underwent elective CABG surgery with CPB and intraoperative GIK infusion were selected for on-pump group and 19 CAD patients (age: 63 ± 10 years, male: 16) were included in the off-pump group. Blood samples were taken before, during and after surgery. Intraoperative samples were withdrawn simultaneously for peripheral vein and sinus coronarius (SC). Plasma adipokine concentrations were measured by ELISA, those of ghrelin by RIA kits.

RESULTS

In response to surgical intervention there was an early, transient fall in plasma levels of adiponectin (p<0.0001) and resistin (p=0.002) followed by an increase to approach their initial values. Plasma ghrelin also increased (p=0.045), this increase, however, was confined to the period of GIK supported CPB. Plasma insulin (p=0.003) and resistin (p=0.009) was significantly higher in the peripheral vein than in SC. The perioperative hormone profile of patients without CPB (off-pump) proved to be comparable to that of on-pump patients in spite of the insulin administration and greater oxidative and inflammatory stress.

CONCLUSIONS

Adipose tissue-derived factors appear to mediate the metabolic and vascular changes that occur in patients with CABG surgery. Epicardial adipose tissue is unlikely to have major contribution to the development of CAD as adipokines are not elevated in SC independent of the mode of intervention.

Adipose tissue and vascular inflammation in coronary artery disease

Obesity has become an important public health issue in Western and developing countries, with well known metabolic and cardiovascular complications. In the last decades, evidence have been growing about the active role of adipose tissue as an endocrine organ in determining these pathological consequences. As a consequence of the expansion of fat depots, in obese subjects, adipose tissue cells develope a phenotypic modification, which turns into a change of the secretory output. Adipocytokines produced by both adipocytes and adipose stromal cells are involved in the modulation of glucose and lipid handling, vascular biology and, moreover, participate to the systemic inflammatory response, which characterizes obesity and metabolic syndrome. This might represent an important pathophysiological link with atherosclerotic complications and cardiovascular events. A great number of adipocytokines have been described recently, linking inflammatory mileu and vascular pathology. The understanding of these pathways is crucial not only from a pathophysiological point of view, but also to a better cardiovascular disease risk stratification and to the identification of possible therapeutic targets. The aim of this paper is to review the role of Adipocytokines as a possible link between obesity and vascular disease.

The association of leptin with dyslipidemia, arterial hypertension and obesity in Kyrgyz (Central Asian nation) population

BACKGROUND

Leptin, an adipocytokine produced by adipose tissue, along with the traditional cardiometabolic risk factors, contributes to the development of cardiovascular complications. At the same time, ethnic features of adipocytokines have been insufficiently investigated, especially among Asians, who have an increased risk of cardiovascular complications compared with Europeans. Aim of study was to investigate the relationship between leptin levels and age, gender, anthropometric parameters, lipid parameters, arterial hypertension (AH), and obesity in the adult population of ethnic Kyrgyz people living in Central Asia.

RESULTS

In total, 322 ethnic Kyrgyz (145 men, 177 women) aged ≥ 30 years were studied. Waist and hip circumference, body mass index, blood glucose, lipids, leptin, and homeostatic model assessment were measured. Patients in the upper quartile of leptin levels had high values of BMI, WC, systolic and diastolic blood pressure, glucose, and HOMA index compared with patients with lower leptin levels. The prevalence of metabolic syndrome and AH increased with higher levels of leptin. Leptin positively correlated with BMI, WC, triglycerides, and glucose concentrations in patients of both sexes. According to the multivariate logistic regression analysis, elevated leptin levels increased by 30 times the risk of obesity in men, regardless of the presence of type 2 diabetes, and 17.7 times in women.

CONCLUSION

Leptin is associated with general and abdominal obesity, dyslipidemia, and insulin resistance in Kyrgyz patients.

Plasma leptin and adiponectin concentrations correlate with cardiometabolic risk and systemic inflammation in healthy, non-obese children

BACKGROUND

Plasma adipocytokines are associated with metabolic profile and cardiovascular risk in obese children.

OBJECTIVE

To investigate the association of plasma leptin and adiponectin concentrations with cardiometabolic risk profile and systemic inflammation in non-obese children.

SUBJECTS

We studied 170 healthy, non-obese children (86 males, mean age 10±2 years).

METHODS

Children's current body mass index (BMI), plasma leptin and adiponectin concentrations, lipid profile, fasting plasma glucose and high sensitivity C reactive protein (hsCRP) were measured.

RESULTS

After adjustment for age, gender and BMI, plasma leptin concentrations were positively associated with hsCRP (t=2.72, p=0.009) and fasting plasma glucose (t=4.27, p<0.0001); plasma adiponectin concentrations were negatively associated with hsCRP (t=-3.31, p=0.0016); and positively with high density lipoprotein cholesterol (t=2.32, p=0.02). Children in the highest quartile of leptin/adiponectin (L/A) ratio demonstrated significantly higher BMI, systolic blood pressure, hsCRP, triglycerides and fasting glucose and the lowest high density lipoprotein (HDL) compared to lower L/A ratio quartiles.

CONCLUSIONS

Alterations in plasma leptin and adiponectin may help to reclassify non-obese children, detecting those with more unfavorable risk profiles independent of BMI status.

The factor structure of the metabolic syndrome in obese individuals with binge eating disorder

OBJECTIVE

Metabolic syndrome (MetS) is strongly linked with cardiovascular disease and type-II diabetes, but there has been debate over which metabolic measures constitute MetS. Obese individuals with binge eating disorder (BED) are one of the high risk populations for developing MetS due to their excess weight and maladaptive eating patterns, yet, the clustering patterns of metabolic measures have not been examined in this patient group.

METHODS

347 adults (71.8% women) were recruited for treatment studies for obese individuals with BED. We used the VARCLUS procedure in the Statistical Analysis System (SAS) to investigate the clustering pattern of metabolic risk measures.

RESULTS

The analysis yielded four factors: obesity (body-mass-index [BMI] and waist circumference), lipids (HDL and triglycerides), blood pressure (systolic and diastolic blood pressure), and glucose regulation (fasting serum glucose and Hb1Ac). The four factors accounted for 84% of the total variances, and variances explained by each factor were not substantially different. There was no inter-correlation between the four factors. Subgroup analyses by sex and by race (Caucasian vs. African American) yielded the same four-factor structure.

CONCLUSION

The factor structure of MetS in obese individuals with BED is not different from those found in normative population studies. This factor structure may be applicable to the diverse population.

Influence of acute hyperlipidemia to adipocyte-derived hormones in lean normotensive and subjects with metabolic syndrome

BACKGROUND

Adipocyte-derived factors and regulators likely contribute to the metabolic syndrome (MetS) in patients with central obesity. This study was undertaken to assess the contribution of leptin, adiponectin, and acylation stimulating protein (ASP-C3ades/ARG) to hemodynamic (blood pressure [BP]) and metabolic (insulin, glucose, lipids) features of MetS.

METHODS

In this study, leptin, adiponectin, and C3ades/ARG were measured at baseline and in response to an infusion of Intralipid(®) and heparin in 12 lean healthy controls and 12 patients with MetS.

RESULTS

Baseline plasma leptin (27.6 ± 6.2 vs. 10.9 ± 3.8 ng/mL, p < 0.01) and plasma C3ades/ARG (273 ± 79 vs 198 ± 57 mg/dL, p < 0.05) were higher in the MetS than control group, whereas baseline plasma adiponectin was higher in the control than MetS group (9.9 ± 1.9 vs. 5.4 ± 0.6 g/mL). Plasma leptin correlated with body mass index (BMI), systolic and diastolic BP (r = 0.53-0.77, p < 0.01). Conversely, adiponectin correlated inversely with insulin, glucose, waist circumference, and insulin sensitivity (r = 0.48-0.51, p ≤ 0.02). Plasma triglycerides increased similarly in MetS and control groups after 4-hours of Intralipid and heparin. C3ades/ARG increased only in lean volunteers. The decrease in triglycerides 1-hour post-infusion was lower in the MetS than control group (-116 ± 33 vs. -282 ± 81 mg/dL, p = 0.01) and correlated inversely with the change in C3ades/ARG.

CONCLUSION

These data suggest that leptin is more closely associated with hemodynamic (BP) aspects of MetS, whereas adiponectin and C3ades/ARG are more closely associated with metabolic components.

Hyperleptinemia, adiposity, and risk of metabolic syndrome in older adults

Background. Abdominal adiposity and serum leptin increase with age as does risk of metabolic syndrome. This study investigates the prospective association between leptin and metabolic syndrome risk in relation to adiposity and cytokines. Methods. The Health, Aging, and Body Composition study is a prospective cohort of older adults aged 70 to 79 years. Baseline measurements included leptin, cytokines, BMI, total percent fat, and visceral and subcutaneous fat. Multivariate logistic regression was used to determine the association between leptin and metabolic syndrome (defined per NCEP ATP III) incidence after 6 years of follow-up among 1,120 men and women. Results. Leptin predicted metabolic syndrome in men (P for trend = 0.0002) and women (P for trend = 0.0001). In women, risk of metabolic syndrome increased with higher levels of leptin (compared with quintile 1, quintile 2 RR = 3.29, CI = 1.36, 7.95; quintile 3 RR = 3.25, CI = 1.33, 7.93; quintile 4 RR = 5.21, CI = 2.16, 12.56; and quintile 5 RR = 7.97, CI = 3.30, 19.24) after adjusting for potential confounders. Leptin remained independently associated with metabolic syndrome risk after additional adjustment for adiposity, cytokines, and CRP. Among men, this association was no longer significant after controlling for adiposity. Conclusion. Among older women, elevated concentrations of leptin may increase the risk of metabolic syndrome independent of adiposity and cytokines.

Evaluation of two single-factor models of metabolic syndrome: a confirmatory factor analysis for an adult population in Beijing

Background

Prevalence of metabolic syndrome is high and increasing in China. The causation of this disorder is, yet, to be fully understood. Several studies with confirmatory factor analysis have been performed to investigate the core of the disease in some races other than Chinese, and amongst the other studies, they have yielded a sound model fit. This study was to evaluate and compare two single-factor models of the underlying factor structure of metabolic syndrome in a Chinese population using confirmatory factor analysis.

Results

Findings showed that in a Chinese sample of 7,472 individuals, Model 1 (with waist circumference, triglycerides/HDL-C ratio, fasting plasma glucose and mean artery pressure) yielded good level of fitness (SRMR < 0.08, CFI > 0.96 and RMSEA < 0.10) in men and women of all age groups; and Model 2 (with waist circumference, triglycerides, fasting plasma glucose and systolic blood pressure) fitted well in men aged 18–34 and over 60 and in all women, except in men of 35–59 (RMSEA = 0.142). In comparison, Model 2 were shown to be better fit (with relative larger GFI and smaller AIC, BIC, CAIC, and EVIC) in women of all age groups and in men of 18–34 and over 60 years old; Model 1 had a better fit in men between 35 and 59.

Conclusions

This study suggests that the single-factor model of metabolic syndrome with waist circumference, triglycerides, fasting plasma glucose and systolic blood pressure are plausible in women of all age groups and young and senior men in Beijing. The model with waist circumference, triglycerides/HDL-C ratio, fasting plasma glucose and mean artery pressure fits middle-aged men.

Prevalence of metabolic syndrome in a cohort of Chinese schoolchildren: comparison of two definitions and assessment of adipokines as components by factor analysis

BACKGROUND

Although attention to metabolic syndrome (MetS) in children has increased, there is still no universally accepted definition and its pathogenesis remains unclear. Our aim was to compare the current definitions of childhood MetS in a Chinese cohort and to examine the clustering pattern of MetS risk factors, particularly inclusion of leptin and adiponectin as additional components.

METHODS

3373 schoolchildren aged 6 to 18 years were recruited. Anthropometric and biochemical parameters and adipokines were measured. MetS was identified using both the International Diabetes Federation (IDF) and a modified Adult Treatment Panel III (ATP III) definitions. Exploratory factor analysis was performed to establish grouping of metabolic characteristics.

RESULTS

For children ≥ 10 years, the prevalence of MetS was 14.3% in the obese group and 3.7% in the overweight group according to the new IDF definition, and 32.3% in the obese group and 8.4% in the overweight group according to the modified ATPIII definition. Frequency of hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C), impaired fasting glucose, elevated blood pressure, and central obesity according to the new IDF definition was 16.7%, 20.7%, 15.8%, 25.5% and 75.5% in obese boys and 14.7%, 24.0%, 12.0%, 11.0% and 89.0% in obese girls, respectively. Metabolic abnormalities in children under 10 years of age were also noted. Using factor analysis on eight conventional variables led to the extraction of 3 factors. Waist circumference (WC) provided a connection between two factors in boys and all three factors in girls, suggesting its central role in the clustering of metabolic risk factors. Addition of leptin and adiponectin also led to the extraction of 3 factors, with leptin providing a connection between two factors in girls. When using WC, mean arterial pressure, triglyceride/HDL-C ratio, HOMA-IR and leptin/adiponectin ratio as variables, a single-factor model was extracted. WC had the biggest factor loading, followed by leptin/adiponectin ratio.

CONCLUSIONS

MetS was highly prevalent amongst obese children and adolescents in this cohort, regardless of the definition used. Central obesity is the key player in the clustering of metabolic risk factors in children, supporting the new IDF definition. Moreover, our findings suggest that a common factor may underlie MetS. Leptin/adiponectin ratio as a possible component of MetS deserves further consideration.

What is metabolic syndrome, and why are children getting it?

Metabolic syndrome comprises a cluster of cardiovascular risk factors (hypertension, altered glucose metabolism, dyslipidemia, and abdominal obesity) that occur in obese children. However, metabolic syndrome can also occur in lean individuals, suggesting that obesity is a marker for the syndrome, not a cause. Metabolic syndrome is difficult to define, due to its nonuniform classification and reliance on hard cutoffs in the evaluation of disorders with non-Gaussian distributions. Defining the syndrome is even more difficult in children, owing to racial and pubertal differences and lack of cardiovascular events. Lipid partitioning among specific fat depots is associated with insulin resistance, which can lead to mitochondrial overload and dysfunctional subcellular energy use and drive the various elements of metabolic syndrome. Multiple environmental factors, in particular a typical Western diet, drive mitochondrial overload, while other changes in Western society, such as stress and sleep deprivation, increase insulin resistance and the propensity for food intake. These culminate in an adverse biochemical phenotype, including development of altered glucose metabolism and early atherogenesis during childhood and early adulthood.

Comparative effects of metformin and pioglitazone on omentin and leptin concentrations in patients with newly diagnosed diabetes: a randomized clinical trial

AIMS

To assess the effects of two commonly used oral hypoglycemic medications metformin and pioglitazone on serum concentrations of omentin and leptin in patients with newly diagnosed type 2 diabetes.

METHODS

In a clinical trial setting (NCT01593371), patients were randomly allocated to either metformin 1000mg daily (n=41), or pioglitazone 30mg daily (n=50). Serum concentrations of omentin and leptin were measured at baseline and after 12weeks. Patients' weight, waist circumference, blood pressure, fasting plasma glucose, fasting insulin, HbA1c, highly sensitive C-reactive protein, and serum lipids were also measured at the two visits.

RESULTS

Baseline concentrations of omentin and leptin were not different between the two arms of the trial. After three months, metformin decreased both omentin and leptin concentrations in women, and leptin concentrations only in men. On the other hand, pioglitazone reduced both adipokines only in women, but not men. Univariate and multivariate ANCOVA models revealed that both interventions are equally effective in reducing omentin concentration (p=0.497 for women and 0.344 for men in multivariate models controlling for the effects of confounding variables). Similarly, neither medication was more effective in reducing leptin concentrations after three months (p=0.822 for women and 0.441 for men in multivariate models).

CONCLUSIONS

Metformin and pioglitazone at pharmacologic doses are equally effective in alteration of serum omentin and leptin concentrations in patients with diabetes, albeit sex differences in response to medications exist. Implication of these findings on long term management and complication prevention of diabetes needs to be elucidated.

[Relationship between leptin and body mass and metabolic syndrome in an adult population]

OBJECTIVE

To analyze the relationship between leptin and obesity expressed as body mass index (BMI) and certain components of the metabolic syndrome (MS) in an adult population.

METHODS

The study included 103 subjects, 42 men and 61 women, aged over 30 years, clinically defined as non-diabetic but with personal or family history of cardiovascular disease. All subjects underwent fasting blood measurements of leptin, insulin, glucose, glucose after ingestion of 75g glucose, HDL cholesterol and triglycerides, and insulin resistance (IR) and BMI were calculated.

RESULTS

BMI as an index of overall adiposity was strongly associated with serum leptin. BMI rose as serum leptin levels increased from the first to the third tertile; the correlation between leptin and BMI was strong, r=0.524 in men and r=0.603 in women, with high statistical significance (p<0.001); BMI was the best predictor of hyperleptinemia on ROC analysis, with area under the curve (AUC)=0.81 in men and 0.84 in women. The association between leptin and obesity (BMI ≥30kg/m(2)) showed high odds ratios (OR) in both sexes (10.11 in men, 6.00 in women) on univariate regression analysis and 9.30 in men and 8.21 in women on multivariate regression analysis. Hyperinsulinemia and IR strongly influenced hyperleptinemia. Leptin was the best predictor of IR in both sexes (AUC=0.89 in men and 0.85 in women), and IR in men (AUC=0.79) and hyperinsulinemia in women (AUC=0.78) were the best predictors of hyperleptinemia after BMI. The correlations between leptin and IR, and leptin and insulinemia, were strong in both sexes. With regard to MS components, increased serum levels of the study variables were observed as leptin concentrations rose from the first to the third tertile (with the exception of HDL cholesterol, which decreased).

CONCLUSION

Elevated serum leptin, particularly in obese individuals, should be taken as a warning sign of energy imbalance, poor diet, hyperinsulinemia, insulin resistance, or changes in other metabolic risk factors that are strongly associated with cardiovascular disease and type 2 diabetes.

Physical activity opposes coronary vascular dysfunction induced during high fat feeding in mice

The study's purpose was to investigate if physical activity initiated with the start of high-fat feeding would oppose development of endothelial dysfunction, and if it does, then to determine some potential mechanisms. C57BL/6 female mice were randomly divided into three groups: (1) control low-fat diet (LF-SED; 15% of calories from fat), (2) high-fat diet (HF-SED; 45% of calories from fat), and (3) HF diet given access to a voluntary running wheel (HF-RUN). Our hypothesis was that HF-RUN would differ in multiple markers of endothelial dysfunction from HF-SED after 10 weeks of 45%-fat diet, but would not differ from LF-SED. HF-RUN differed from HF-SED in nine determinations in which HF-SED either had decreases in (1) acetylcholine (ACh)-induced and flow-induced vasodilatations in isolated, pressurized coronary arterioles, (2) heart phosphorylated endothelial nitric oxide synthase (p-eNOS/eNOS) protein, (3) coronary arteriole leptin (ob) receptor protein, (4) phosphorylated signal transducer and activator of transcription 3 (p-STAT3/STAT3) protein, and (5) coronary arteriole superoxide dismutase 1 protein; or had increases in (6) percentage body fat, (7) serum leptin, (8) coronary arteriole suppressor of cytokine signalling 3 (SOCS3) protein, and (9) coronary arteriole gp91(phox) protein. Higher endothelium-dependent vasodilatation by ACh or leptin was abolished with incubation of NOS inhibitor N(G)-nitro-l-arginine-methyl ester (l-NAME) in LF-SED and HF-RUN groups. Further, impaired ACh-induced vasodilatation in HF-SED was normalized by apocynin or TEMPOL to LF-SED and HF-RUN. These findings demonstrate multiple mechanisms (eNOS, leptin and redox balance) by which voluntary running opposes the development of impaired coronary arteriolar vasodilatation during simultaneous high-fat feeding.

Sex dimorphism in the relation between early adiposity and cardiometabolic risk in adolescents

CONTEXT

Birth weight and childhood adiposity are associated with subsequent cardiovascular risk.

OBJECTIVE

We investigated the associations between metabolic clusters in young adults with body fat distribution from early childhood, focusing on sex differences.

DESIGN, SETTING, AND PATIENTS

A total of 1053 17 yr olds from an Australian birth cohort had measures of anthropometry, blood pressure, and fasting insulin, glucose, and lipids.

MAIN OUTCOME MEASURES

Two-step cluster analysis identified 17 yr olds at high metabolic risk. The two risk groups were compared by sex with regard to birth weight and serial anthropometry, including skinfold thickness from nine time-points.

RESULTS

The "high-risk" metabolic cluster at age 17 yr included 16% of males and 19% of females. Compared to the "low-risk" group, the high-risk cluster participants had greater waist circumference, triglycerides, insulin, and systolic blood pressure and lower high-density lipoprotein-cholesterol (all P <0.0001). There was a significant birth weight by sex interaction upon the metabolic cluster outcome (P = 0.011). Compared to their low-risk counterparts, females in the high-risk cluster at 17 yr were heavier from birth (odds ratio, 1.8; 95% confidence interval, 1.0, 3.2) (P = 0.034), with consistently higher body mass index and skinfold thickness thereafter. In contrast, there was no statistical difference in birth weight between high- and low-risk males (odds ratio, 0.62; 95% confidence interval, 0.38, 1.02).

CONCLUSIONS

These data show sexual dimorphism in effects of early life body mass index and fat distribution upon cardiometabolic risk factors. Females in a contemporary population are particularly prone to increased risk when born heavier. This has implications for targeted prevention of obesity and metabolic diseases with increasing maternal obesity and gestational diabetes.

Obesity in cancer survival

Although obesity is a well-known risk factor for several cancers, its role on cancer survival is poorly understood. We conducted a systematic literature review to assess the current evidence evaluating the impact of body adiposity on the prognosis of the three most common obesity-related cancers: prostate, colorectal, and breast. We included 33 studies of breast cancer, six studies of prostate cancer, and eight studies of colo-rectal cancer. We note that the evidence overrepresents breast cancer survivorship research and is sparse for prostate and colorectal cancers. Overall, most studies support a relationship between body adiposity and site-specific mortality or cancer progression. However, most of the research was not specifically designed to study these outcomes and, therefore, several methodological issues should be considered before integrating their results to draw conclusions. Further research is urgently warranted to assess the long-term impact of obesity among the growing population of cancer survivors.

Apolipoproteins a-I and B as components of metabolic syndrome with respect to diabetes status: a factor analysis

BACKGROUND

The aim of the current study was to elucidate the clustering pattern of metabolic syndrome components along with apolipoproteins (Apo) A-I and B in diabetic and nondiabetic subjects.

METHODS

Factor analysis of conventional variables of metabolic syndrome [i.e., waist circumference, homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG), high-density lipoprotein-cholesterol (HDL-C), and systolic blood pressure (SBP)] with or without addition of Apo A-I and B was performed on 567 and 327 diabetic and nondiabetic subjects, respectively. Thereafter, analyses were repeated after substitution of TG and HDL-C by the TG-to-HDL-C ratio (TG/HDL-C).

RESULTS

Regarding conventional variables of metabolic syndrome, one or two underlying factors were identified, depending on whether lipid measures were entered as two distinct variables or as a composite measure. Apolipoproteins were consistent with a one-factor structure model of metabolic syndrome and did not change the loading pattern remarkably in nondiabetics. TG and HDL-C tended to cluster with Apo B and A-I, respectively, in different models.

CONCLUSION

The current study confirms that addition of Apo A-I and B is consistent with the one-factor model of metabolic syndrome and does not modify the loading pattern remarkably in nondiabetic subjects.

Variation in metabolic responses to meal challenges differing in glycemic index in healthy women: Is it meaningful?

BACKGROUND

Established clinical tests are commonly used in disease diagnosis, but tools that enhance identification of metabolic dysfunctions are needed. This study was conducted to identify typical and atypical metabolite temporal patterns in response to paired meal challenge tests.

DESIGN

Metabolic responses to high and low glycemic index (GI) meals were tested in 24 healthy pre-menopausal women, aged 20-50 y, with BMI of 25-30 kg/m2 using a cross-over design. On test days, blood glucose, insulin, leptin and non-esterified fatty acids were measured after an overnight fasting, and for 8 h following test meal consumption. The data were range scaled, and multivariate statistics were used to assess the presence of distinct response groups to the meal challenge tests.

RESULTS

As expected, participants showed higher circulating glucose and insulin in response to the high GI compared to the low GI meal challenge. However, using range-scaling and Principal Component Analysis, three distinct groups were identified based on differential responses to the paired challenges. Members of the most populated group (n = 18) displayed little deviation from the expected response to the two meal challenges. Two minor groups (n = 3/group) with distinct responses were observed, one suggestive of sub-clinical insulin resistance, and the other suggestive of hyperleptinemia.

CONCLUSIONS

The differential responses of glucose, insulin and leptin to low and high glycemic test meals revealed three response groups. Dietary intervention studies traditionally evaluate group responses, and aim to identify the overall effect in the population studied. In contrast, our study analyzed the variance in the meal challenge responses, using an integrated physiological approach, rather than a reductionist approach. This phenotyping approach may be useful for detecting subclinical metabolic dysfunctions, and it could contribute to improved personalized nutrition management. This study is registered in ClinicalTrials.gov, record #200210295.

Insulin resistance: a significant risk factor of endometrial cancer

OBJECTIVE

To review the role played by insulin resistance in the development of endometrial cancer.

METHODS

Relevant manuscripts and studies were searched on Medline using the terms endometrial cancer, insulin resistance, obesity, adipokine, C-peptide, leptin, adiponectin, plasminogen activator inhibitor-1, insulin, PI3K/Akt, Ras/MAPK and metformin alone or in combination.

RESULTS

Epidemiological studies have shown that insulin resistance is an important potential risk factor of endometrial cancer, and several research studies have been undertaken to determine the mechanism underlying its link to this malignant disease. Risk factors of insulin resistance, such as the inflammatory mediators, adipokines adiponectin, leptin and plasminogen activator inhibitor-1 and excessive androgen are also risk factors of endometrial cancer. High levels of insulin induced by insulin resistance have been found to exert direct and indirect effects that contribute to the development of endometrial cancer. Insulin directly promotes cell proliferation and survival through the PI3K/Akt and Ras/MAPK pathways. Moreover, the network among insulin, estrogen and insulin-like growth factor-1 also contributes to the development of endometrial cancer. Indirectly, insulin leads to changes in sex hormone levels, including increases in the levels of estrogen. Additionally, a small number of studies suggested that metformin, an insulin-sensitizing agent, has therapeutic potential for endometrial cancer.

CONCLUSIONS

This evidence suggests that insulin resistance plays a central role in endometrial cancer development. Understanding the relationship between insulin resistance and endometrial cancer may supply new ideas to fight this malignancy. Furthermore, combating insulin resistance may be a useful preventive and therapeutic strategy for endometrial cancer.

Obesity: from the agricultural revolution to the contemporary pediatric epidemic

Obesity is pandemic in Western society. Currently, approximately 100 million Americans are overweight (body mass index > 25 kg/m2) or obese (body mass index > 30 kg/m2). The pandemic is largely attributable to the relatively recent (from an evolutionary perspective) adoption of a sedentary lifestyle, coupled with the high availability of foods with high caloric content in Western cultures. These factors superimposed on dated genotypes have given rise to the global obesity epidemic. Over the past two decades, the discovery of leptin and other new molecules (e.g., adiponectin, resistin, ghrelin) has shed significant light on the pathophysiologic mechanisms of obesity-related morbidities, many of which became apparent through human epidemiologic studies during the last half of the 20th century. Of high concern for modern Western societies is the pediatric obesity epidemic, which stands to cripple Western cultures, both literally and financially in terms of health care costs and exhaustion of finite medical resources. The prevalence of childhood obesity has more than tripled since the 1960s, and 12.5 million (~17%) of children and teenagers are obese in the United States today. The rate of increasing prevalence of childhood obesity is staggering, and the collective efforts of the pediatric medical community and scientists are essential for battling the epidemic.

The clinical impact of plasma leptin levels in a cohort of chronic kidney disease patients

Background

Recent research has clarified the relationship between adipokines, metabolic syndrome (MS) and cardiovascular disease (CVD). The results of animal and clinical studies have revealed a positive relationship between leptin and vascular smooth muscle cell counts and calcification, arterial rigidity, carotid thickness and the incidence of CVD. However, despite leptin fulfilling the definition of a uremic toxin, its exact role in chronic kidney disease (CKD) has yet to be determined.

Methods

One hundred and forty-two CKD patients (stages 2–5D) participated in this study, and were followed for a minimum of 20 months at Amiens University Medical Center.

Results

Leptin was negatively correlated with the glomerular filtration rate (GFR), total adiponectin (TAdip) and high-molecular weight adiponectin and positively correlated with age, waist circumference, body mass index (BMI), aortic calcification score (ACS), C-reactive protein (CRP), triglycerides, insulin and parathormone (PTH). Leptin and insulin were significantly correlated with the MS score. The BMI, insulin, MS score and PTH were independent predictors of leptin levels (P = 0.002, 0.016, 0.028 and 0.017, respectively). Leptin, insulin and TAdip were independent predictors of the presence of MS (P = 0.05, 0.04 and 0.04). However, leptin levels were not significantly predictive of the clinical outcomes.

Conclusions

Our study was the first to demonstrate a significant, independent link between leptin and MS (but not clinical outcomes) and PTH in patients at different CKD stages. Future studies will have to assess the involvement of leptin in MS and clinical outcomes in CKD, and the potential modulation of leptin by PTH.

Contribution of serum leptin to metabolic syndrome in obese and nonobese subjects

BACKGROUND AND AIMS

Little evidence exists regarding the association of leptin with metabolic syndrome (MetS) as defined by conventional criteria. Moreover, the contribution of obesity to this relationship is not well understood. This study aimed to evaluate the association between leptin concentrations with MetS in obese and nonobese subjects.

METHODS

Data from the Third National Surveillance of Risk Factors of Non-Communicable Diseases (SuRFNCD) in Iran was used. In a cross-sectional study of 3045 adults (48.2% men) aged 25-64 years, anthropometric indices, blood pressure, fasting plasma glucose, fasting insulin, lipid profile [triglycerides, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides], and fasting leptin were measured. Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) was also calculated.

RESULTS

Leptin concentrations were 2.6 fold higher in women compared with men. Subjects with MetS had significantly higher leptin concentrations. Leptin concentrations increased steadily with an increment in the number of MetS components (p <0.001). Leptin was significantly associated with MetS after adjustment for age, cigarette smoking, medication use, physical activity, HOMA-IR, and LDL-C. The significant association between leptin and MetS persisted after adjustment for body mass index (OR: 1.31, 95% CI: 1.09-1.58 in males and 1.17, 95% CI: 1.01-1.38 in females) and waist circumference (OR: 1.24 95% CI: 1.01-1.51 in men and 1.22, 95% CI: 1.04-1.43 in women). After dividing subjects into obese and nonobese, leptin concentrations were again significantly higher in subjects with MetS in both groups.

CONCLUSIONS

We demonstrated that leptin concentrations are significantly associated with International Diabetes Federation (IDF)-defined MetS, independent of overall and central obesity. Our findings point to an independent role for leptin in development of MetS.

Serum adipokine levels in type 1 diabetic patients: association with carotid intima media thickness

BACKGROUND

Adipokines are markers of insulin resistance and play a role in the atherosclerotic process. The association of adipokines with the macrovascular complications of type 1 diabetes mellitus (DM) needs to be determined. The aim of this study was to measure serum adiponectin, leptin, and resistin levels in type 1 DM patients and investigate their relationship with carotid intima media thickness (CIMT), a clinical marker of atherosclerosis.

METHODS

Seventy-five type 1 DM patients and 115 sex and age-matched healthy controls were included in the study. Serum adiponectin, leptin, and resistin levels were measured by the enzyme-linked immunosorbent assay (ELISA method). CIMT was assessed by Doppler ultrasonography.

RESULTS

Adiponectin levels in diabetics were higher (25.8±14.8 μg/mL vs. 5.5±7.3 μg/mL; P<0.0001) and leptin levels were lower than controls (9.4±6.2 ng/mL vs. 12.8±8.6 ng/mL; P=0.01). Resistin levels were also higher in the diabetic group compared to controls (2.1±1.4 ng/mL vs. 1.6±0.8 ng/mL; P=0.04). Adiponectin was correlated negatively with CIMT (r=-0.24, P=0.03), age (r=-0.30, P=0.02), BMI (r=-0.33, P=0.02), waist-to-hip ratio (WHR) (r=-0.38, P=0.01) and positively with creatinine (r=0.44, P=0.004). Leptin levels were correlated with total cholesterol (r=0.53, P=0.01) and high-density lipoprotein (HDL) (r=0.67, P=0.001). Resistin was correlated with CIMT (r=0.24, P=0.03) and systolic blood pressure (r=0.48, P=0.009). Multivariate analysis revealed resistin and creatinine to be independent predictors of CIMT among adiponectin, leptin, resistin, WHR, glycosylated hemoglobin (HbA1c), and creatinine.

CONCLUSIONS

Increased adiponectin correlates negatively and resistin positively with CIMT in type 1 diabetic patients, but adjusting for other known predictors reveals only resistin to be associated with subclinical atherosclerosis in this group of patients.

Leptin cut-off values for determination of metabolic syndrome: third national surveillance of risk factors of non-communicable diseases in Iran (SuRFNCD-2007)

Leptin is strongly contributed to the clustering of metabolic syndrome (MetS) components and potentially can be regarded as a single predictor of MetS. This population-based study, for the first time, reports the diagnostic accuracy of different leptin cut-points for determining MetS. Further, the current study compares the predictive ability of the appropriate threshold of leptin with insulin resistance. Data of the individuals without history of known diabetes mellitus, aged 25-64 years, from the third national surveillance of risk factors of non-communicable diseases (SuRFNCD-2007) were analyzed. MetS was defined due to either adult treatment panel III (ATPIII) or the modified international diabetes federation (IDF) criteria. Receiver-operating characteristic (ROC) curves were depicted to define cut-off of serum leptin, using the maximum Youden index and the shortest distance methods. Further, the values of leptin cut-offs in prediction of MetS were compared with those of insulin resistance (defined as homeostasis model assessment of insulin resistance >1.775). In men, the optimal cut-offs of leptin for IDF- and ATPIII-defined MetS were 3.6 ng/ml (positive predictive value, PPV: 56.5%; negative predictive value, NPV: 72.7%) and 4.1 ng/ml (PPV: 49.6%; NPV: 78.1%), respectively. In women, the optimal threshold was equal to 11.0 ng/ml (PPV: 53.8%; NPV: 73.0% for IDF criteria and PPV: 60.1%; NPV: 64.9% for ATPIII criteria). The diagnostic accuracy of these values in identifying MetS was similar to that of insulin resistance. Therefore, leptin is comparable to insulin resistance in identifying MetS and can be used as single predictor of MetS.

Weight gain following treatment with valproic acid: pathogenetic mechanisms and clinical implications

In the last years, a growing body of literature indicates an association between valproic acid therapy and weight gain. Weight gain during valproate treatment can be observed within the first 3 months of therapy and women seem to be more susceptible than men. The mechanism through which valproic acid may induce a weight gain is still controversial. The scope of this paper is to investigate the possible causal link between treatment and weight gain in epileptic patients. Systematic review of published epidemiological studies has been done in order to evaluate the real extent of this side effect of valproic acid and its clinical implications, such as an increased risk of insulin resistance and other secondary metabolic abnormalities. The knowledge of the potential of valproic acid to cause significant changes in body weight will help in appropriate selection and modification of antiepileptic therapy to minimize the risk for weight abnormalities. Measurements of body weight before initiation of valproic acid therapy should be done as part of the monitoring of patients with epilepsy to detect changes before there are serious adverse consequences; an increase of 2 kg of body weight after 1 month of treatment should imply considerations to change antiepileptic drug therapy.