Future adverse cardiac events can be predicted by persistently low plasma adiponectin concentrations in men and marked reductions of adiponectin in women after acute myocardial infarction

Relationship between adiponectin and blood pressure in obese Latino adolescent boys with a family history of type 2 diabetes

INTRODUCTION

Adipokines are associated with several pathological states including, metabolic syndrome, obesity, insulin resistance and type 2 diabetes. One of these adipokines, adiponectin is of particular interest as it has been shown to have numerous anti-inflammatory effects, However, the association between adiponectin and blood pressure remains inconclusive especially in the Latino adolescent with obesity.

PURPOSE

To investigate the relationship between plasma adiponectin and blood pressure in Latino adolescents' boys with obesity and a with a family history of Type 2 diabetes.

METHODS

Thirty two Latino adolescent males with obesity aged 14-17 years with a family history of type 2 diabetes underwent a frequently sampled glucose tolerance test (FSIVGTT) to measure insulin sensitivity. Body composition was assessed using dual energy x-ray absorptiometry. Obesity was defined as having a BMI percentile ≥95. Blood pressure was assessed using the Dinamap automated blood pressure monitor, and the average of three readings was used in the analysis. Fasting plasma adiponectin was determined using radioimmunoassay.

RESULTS

There were moderate positive significant correlations for adiponectin and Systolic blood pressure(SBP) (rho = 0.436, p < 0.027) and Diastolic blood pressure(DBP) (rho = 0.41,p < 0.028). A multivariate liner regression showed that plasma adiponectin could significantly detect 19% of the variance in SBP (p = 0.017, and 33% for DBP (p = 0.017). In a simple linear regression adiponectin was not related to any of our variables (p < 0.05).

CONCLUSION

In conclusion, adiponectin was positively and significantly correlated to blood pressure in Latino adolescent with obesity. Future studies should investigate this relationship in a large sample of Latino adolescent youth.

Hypoadiponectinemia-induced upregulation of microRNA449b downregulating Nrf-1 aggravates cardiac ischemia-reperfusion injury in diabetic mice

Diabetes enhances myocardial ischemic/reperfusion (MI/R) injury via an incompletely understood mechanism. Adiponectin (APN) is a cardioprotective adipokine suppressed by diabetes. However, how hypoadiponectinemia exacerbates cardiac injury remains incompletely understood. Dysregulation of miRNAs plays a significant role in disease development. However, whether hypoadiponectinemia alters cardiac miRNA profile, contributing to diabetic heart injury, remains unclear. Methods and Results: Wild-type (WT) and APN knockout (APN-KO) mice were subjected to MI/R. A cardiac microRNA profile was determined. Among 23 miRNAs increased in APN-KO mice following MI/R, miR-449b was most significantly upregulated (3.98-fold over WT mice). Administrating miR-449b mimic increased apoptosis, enlarged infarct size, and impaired cardiac function in WT mice. In contrast, anti-miR-449b decreased apoptosis, reduced infarct size, and improved cardiac function in APN-KO mice. Bioinformatic analysis predicted 73 miR-449b targeting genes, and GO analysis revealed oxidative stress as the top pathway regulated by these genes. Venn analysis followed by luciferase assay identified Nrf-1 and Ucp3 as the two most important miR-449b targets. In vivo administration of anti-miR-449b in APN-KO mice attenuated MI/R-stimulated superoxide overproduction. In vitro experiments demonstrated that high glucose/high lipid and simulated ischemia/reperfusion upregulated miR-449b and inhibited Nrf-1 and Ucp3 expression. These pathological effects were attenuated by anti-miR-449b or Nrf-1 overexpression. In a final attempt to validate our finding in a clinically relevant model, high-fat diet (HFD)-induced diabetic mice were subjected to MI/R and treated with anti-miR-449b or APN. Diabetes significantly increased miR-449b expression and downregulated Nrf-1 and Ucp3 expression. Administration of anti-miR-449b or APN preserved cardiac Nrf-1 expression, reduced cardiac oxidative stress, decreased apoptosis and infarct size, and improved cardiac function. Conclusion: We demonstrated for the first time that hypoadiponectinemia upregulates miR-449b and suppresses Nrf-1/Ucp3 expression, promoting oxidative stress and exacerbating MI/R injury in this population. Dysregulated APN/miR-449b/oxidative stress pathway is a potential therapeutic target against diabetic MI/R injury.

Relationship between Adiponectin and Blood Pressure in Obese Latino Adolescent Boys with a Family History of Type 2 Diabetes

INTRODUCTION

Adipokines are associated with several pathological states including, metabolic syndrome, obesity, insulin resistance and type 2 diabetes. One of these adipokines, adiponectin is of particular interest as it has been shown to have numerous anti-inflammatory effects, However, the association between adiponectin and blood pressure remains inconclusive especially in the obese Hispanic adolescent.

PURPOSE

to investigate the relationship between plasma adiponectin and blood pressure in obese Latino adolescents' boys with a family history of Type 2 diabetes.

METHODS

Thirty two obese Latino male adolescents aged 14-17 years with a family history of type 2 diabetes underwent a frequently sampled glucose tolerance test (FSIVGTT) to measure insulin sensitivity. Body composition was assessed using dual energy x-ray absorptiometry. Obesity was defined as having a BMI percentile 395. Blood pressure was assessed using the Dinamap automated blood pressure monitor, and the average of three readings was used in the analysis. Fasting plasma adiponectin was determined using radioimmunoassay.

RESULTS

There was a strong positive significant correlation for adiponectin and Systolic blood pressure(SBP) (p< 0.027) and a moderate, positive significant correction for Diastolic blood pressure(DBP) (p< 0.028). A multivariate liner regression showed that plasma adiponectin could significantly predict 19% of the variance in SBP (p=0.017, and 33% for DBP (p=0.017).

CONCLUSION

In conclusion, adiponectin was positively and significantly correlated to blood pressure in obese Latino adolescent youth. Future studies should investigate this relationship in a large sample of Latino adolescent youth.

Prognostic role of inflammatory cytokines and novel adipokines in acute myocardial infarction: An updated and comprehensive review

Acute myocardial infarction (AMI) is one of the major causes of morbidity and mortality worldwide. The inflammation response during and after AMI is common and seems to play a key role in the peri-AMI period, related with ischaemia-reperfusion injury, adverse cardiac remodelling, infarct size and poor prognosis. In this article, we provide an updated and comprehensive overview of the most important cytokines and adipokines involved in the complex pathophysiology mechanisms in AMI, summarizing their prognostic role post-AMI. Data so far support that elevated levels of the major proinflammatory cytokines TNFα, IL-6 and IL-1 and the adipokines adiponectin, visfatin and resistin, are linked to high mortality and morbidity. In contrary, there is evidence that anti-inflammatory cytokines and adipokines as IL-10, omentin-1 and ghrelin can suppress the AMI-induced inflammatory response and are correlated with better prognosis. Mixed data make unclear the role of the novel adipokines leptin and apelin. After all, imbalance of pro-inflammatory and anti-inflammatory cytokines may result in worst AMI prognosis. The incorporation of these inflammation biomarkers in established prognostic models could further improve their prognostic power improving overall the management of AMI patients.

Aerobic exercise training reduces cardiac function and coronary flow-induced vasodilation in mice lacking adiponectin

We tested the hypothesis that adiponectin deficiency attenuates cardiac and coronary microvascular function and prevents exercise training-induced adaptations of the myocardium and the coronary microvasculature in adult mice. Adult wild-type (WT) or adiponectin knockout (adiponectin KO) mice underwent treadmill exercise training or remained sedentary for 8-10 wk. Systolic and diastolic functions were assessed before and after exercise training or cage confinement. Vasoreactivity of coronary resistance arteries was assessed at the end of exercise training or cage confinement. Before exercise training, ejection fraction and fractional shortening were similar in adiponectin KO and WT mice, but isovolumic contraction time was significantly lengthened in adiponectin KO mice. Exercise training increased ejection fraction (12%) and fractional shortening (20%) with no change in isovolumic contraction time in WT mice. In adiponectin KO mice, both ejection fraction (-9%) and fractional shortening (-12%) were reduced after exercise training and these decreases were coupled to a further increase in isovolumic contraction time (20%). In sedentary mice, endothelium-dependent dilation to flow was higher in arterioles from adiponectin KO mice as compared with WT mice. Exercise training enhanced dilation to flow in WT mice but decreased flow-induced dilation in adiponectin KO mice. These data suggest that compensatory mechanisms contribute to the maintenance of cardiac and coronary microvascular function in sedentary mice lacking adiponectin; however, in the absence of adiponectin, cardiac and coronary microvascular adaptations to exercise training are compromised.NEW & NOTEWORTHY We report that compensatory mechanisms contribute to the maintenance of cardiac and coronary microvascular function in sedentary mice in which adiponectin has been deleted; however, when mice lacking adiponectin are subjected to the physiological stress of exercise training, beneficial coronary microvascular and cardiac adaptations are compromised or absent.

Tissue-specific role and associated downstream signaling pathways of adiponectin

According to the World Health Organization, metabolic syndrome (MetS) can be defined as a pathological condition characterized by abdominal obesity, insulin resistance, hypertension, and hyperlipidemia. The incidence of MetS keeps rising, as at least 35% of the USA population suffers from MetS. One of the worst comorbidities of metabolic syndrome are cardiovascular diseases that significantly amplifies the mortality associated with this syndrome. There is an urgent need to understand the pathophysiology of MetS to find novel diagnosis, treatment and management to mitigate the MetS and associated complications. Altered circulatory adiponectin levels have been implicated in MetS. Adiponectin has numerous biologic functions including antioxidative, anti-nitrative, anti-inflammatory, and cardioprotective effects. Being a pleiotropic hormone of multiple tissues, tissue-specific key signaling pathways of adiponectin will help finding specific target/s to blunt the pathophysiology of metabolic syndrome and associated disorders. The purpose of this review is to elucidate tissue-specific signaling pathways of adiponectin and possibly identify potential therapeutic targets for MetS as well as to evaluate the potential of adiponectin as a biomarker/therapeutic option in MetS.

Relation of Adiponectin to Cardiovascular Events and Mortality in Patients With Acute Coronary Syndrome

The association between serum adiponectin levels and cardiovascular events, particularly how adiponectin predicts the development of cardiovascular events and mortality in acute coronary syndrome (ACS) patients remains unresolved. Hence, we aimed to determine whether higher adiponectin levels predict cardiovascular events and mortality in these patients. Regression analyses were performed to clarify adiponectin's ability to predict cardiovascular events and mortality among 1,641 ACS patients. Subgroup analyses were performed according to gender, age, and body mass index (BMI). The primary end point was a composite of the first all-cause death, nonfatal myocardial infarction, or nonfatal stroke event. The secondary end point was all-cause death. Hazard ratios for the primary and secondary end points per 5-µg/ml increase in adiponectin levels were 1.31 (95% confidence interval [CI], 1.13 to 1.47; p = 0.0007) and 1.32 (95% CI, 1.13 to 1.51; p = 0.001), respectively. Higher adiponectin levels were associated with increased cardiovascular events in men, patients aged ≥65 years, and those with BMI <25 kg/m². In conclusion, higher adiponectin levels were associated with increased cardiovascular events and all-cause mortality in ACS patients. Its predictive ability might be limited in women, patients aged <65 years, and patients with BMI ≥25 kg/m².

Molecular Mechanisms of Adiponectin-Induced Attenuation of Mechanical Stretch-Mediated Vascular Remodeling

Hypertension induces vascular hypertrophy, which changes blood vessels structurally and functionally, leading to reduced tissue perfusion and further hypertension. It is also associated with dysregulated levels of the circulating adipokines leptin and adiponectin (APN). Leptin is an obesity-associated hormone that promotes vascular smooth muscle cell (VSMC) hypertrophy. APN is a cardioprotective hormone that has been shown to attenuate hypertrophic cardiomyopathy. In this study, we investigated the molecular mechanisms of hypertension-induced VSMC remodeling and the involvement of leptin and APN in this process. To mimic hypertension, the rat portal vein (RPV) was mechanically stretched, and the protective effects of APN on mechanical stretch-induced vascular remodeling and the molecular mechanisms involved were examined by using 10 μg/ml APN. Mechanically stretching the RPV significantly decreased APN protein expression after 24 hours and APN mRNA expression in a time-dependent manner in VSMCs. The mRNA expression of the APN receptors AdipoR1, AdipoR2, and T-cadherin significantly increased after 15 hours of stretch. The ratio of APN/leptin expression in VSMCs significantly decreased after 24 hours of mechanical stretch. Stretching the RPV for 3 days increased the weight and [³H]-leucine incorporation significantly, whereas APN significantly reduced hypertrophy in mechanically stretched vessels. Stretching the RPV for 10 minutes significantly decreased phosphorylation of LKB1, AMPK, and eNOS, while APN significantly increased p-LKB1, p-AMPK, and p-eNOS in stretched vessels. Mechanical stretch significantly increased p-ERK1/2 after 10 minutes, whereas APN significantly reduced stretch-induced ERK1/2 phosphorylation. Stretching the RPV also significantly increased ROS generation after 1 hour, whereas APN significantly decreased mechanical stretch-induced ROS production. Exogenous leptin (3.1 nM) markedly increased GATA-4 nuclear translocation in VSMCs, whereas APN significantly attenuated leptin-induced GATA-4 nuclear translocation. Our results decipher molecular mechanisms of APN-induced attenuation of mechanical stretch-mediated vascular hypertrophy, with the promising potential of ultimately translating this protective hormone into the clinic.

Increased serum adiponectin predicts improved coronary flow and clinical outcomes in patients with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention

Background

Previous studies suggested that adiponectin (APN) could ameliorate ischemia/reperfusion injury and endothelial dysfunction in patients with acute myocardial infarction. However, the relationship between serum APN level and coronary flow after primary percutaneous coronary intervention (PPCI) in patients with ST‐segment elevation myocardial infarction (STEMI) is unclear.

Methods

A total of 144 patients with STEMI treated by PPCI were enrolled and divided into two groups based on the mean serum APN level on admission. The data on coronary angiograms and laboratory examinations were collected and compared between groups. The incidence of major adverse cardiac events (MACE) was evaluated in all enrolled patients.

Results

The prevalence of Thrombolysis In Myocardial Infarction (TIMI) flow grade <3 after PPCI and corrected TIMI frame count were lower in the high‐APN group (P = 0.032 and P = 0.029, respectively). Logistic regression analysis demonstrated that APN was an independent negative predictor of poor coronary flow after PPCI (odds ratio = 0.72, 95% CI: 0.56‐0.93, P = 0.011). Kaplan‐Meier curves showed that a higher APN level correlated with a better MACE‐free survival rate, and multivariate Cox hazard regression analysis indicated that high APN was a significant negative predictor of MACE (hazard ratio = 0.54, 95% CI: 0.29‐1.00, P = 0.048).

Conclusion

Elevated serum levels of APN on admission are associated with improved myocardial blood flow and clinical outcomes in STEMI patients treated with PPCI.

Examining the Potential of Developing and Implementing Use of Adiponectin-Targeted Therapeutics for Metabolic and Cardiovascular Diseases

Cardiometabolic diseases encompass those affecting the heart and vasculature as well as other metabolic problems, such as insulin resistance, diabetes, and non-alcoholic fatty liver disease. These diseases tend to have common risk factors, one of which is impaired adiponectin action. This may be due to reduced bioavailability of the hormone or resistance to its effects on target tissues. A strong negative correlation between adiponectin levels and cardiometabolic diseases has been well-documented and research shown that adiponectin has cardioprotective, insulin sensitizing and direct beneficial metabolic effects. Thus, therapeutic approaches to enhance adiponectin action are widely considered to be desirable. The complexity of adiponectin structure and function has so far made progress in this area less than ideal. In this article we will review the effects and mechanism of action of adiponectin on cardiometabolic tissues, identify scenarios where enhancing adiponectin action would be of clinical value and finally discuss approaches via which this can be achieved.

Gender-linked impact of epicardial adipose tissue volume in patients who underwent coronary artery bypass graft surgery or non-coronary valve surgery

Background

Traditional and non-traditional risk factors for atherosclerotic cardiovascular disease (ASCVD) are different between men and women. Gender-linked impact of epicardial adipose tissue volume (EATV) in patients undergoing coronary artery bypass grafting (CABG) remains unknown.

Methods

Gender-linked impact of EATV, abdominal fat distribution and other traditional ASCVD risk factors were compared in 172 patients (men: 115; women: 57) who underwent CABG or non-coronary valvular surgery (non-CABG).

Results

In men, EATV, EATV index (EATV/body surface area) and the markers of adiposity such as body mass index, waist circumference and visceral fat area were higher in the CABG group than in the non-CABG group. Traditional ASCVD risk factors were also prevalent in the CABG group. In women, EATV and EATV index were higher in the CABG group, but other adiposity markers were comparable between CABG and non-CABG groups. Multivariate logistic regression analysis showed that in men, CABG was determined by EATV Index and other ASCVD risk factors including hypertension, dyslipidemia, adiponectin, high sensitive C-reactive protein (hsCRP) and type 2 diabetes mellitus (Corrected R² = 0.262, p < 0.0001), while in women, type 2 diabetes mellitus is a single strong predictor for CABG, excluding EATV Index (Corrected R² = 0.266, p = 0.005).

Conclusions

Our study found that multiple risk factors, including epicardial adipose tissue volume and traditional ASCVD factors are determinants for CABG in men, but type 2 diabetes mellitus was the sole determinant in women. Gender-specific disparities in risk factors of CABG prompt us to evaluate new diagnostic and treatment strategies and to seek underlying mechanisms.

Unravelling the adiponectin paradox: novel roles of adiponectin in the regulation of cardiovascular disease

Adipose tissue (AT) has recently been identified as a dynamic endocrine organ secreting a wide range of adipokines. Adiponectin is one such hormone, exerting endocrine and paracrine effects on the cardiovascular system. At a cellular and molecular level, adiponectin has anti-inflammatory, antioxidant and anti-apoptotic roles, thereby mitigating key mechanisms underlying cardiovascular disease (CVD) pathogenesis. However, adiponectin expression in human AT as well as its circulating levels are increased in advanced CVD states, and it is actually considered by many as a 'rescue hormone'. Due to the complex mechanisms regulating adiponectin's biosynthesis in the human AT, measurement of its levels as a biomarker in CVD is highly controversial, given that adiponectin exerts protective effects on the cardiovascular system but at the same time its increased levels flag advanced CVD. In this review article, we present the involvement of adiponectin in CVD pathogenesis and we discuss its role as a clinical biomarker.

LINKED ARTICLES

This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.

The Relationship between Metabolically Obese Non-Obese Weight and Stroke: The Korea National Health and Nutrition Examination Survey

Objective

Both metabolic syndrome (MetS) and obesity increase the risk of stroke. However, few studies have compared the risks of stroke associated with metabolically obese non-obese weight (MONW) and metabolically healthy obesity (MHO). This study aimed to compare the prevalence of stroke in MONW and MHO individuals.

Methods

A total of 25,744 subjects aged ≥40 years were selected from the 2007–2014 Korean National Health and Nutrition Examination Survey. MetS was defined using 2001 National Cholesterol Education Program/Adult Treatment Panel III and 2005 American Heart Association/National Heart, Lung, and Blood Institute criteria. Non-obese weight and obesity were defined as a body mass index (BMI) <25 kg/m² and ≥25 kg/m², respectively. MONW was defined as meeting the MetS criteria with a BMI <25 kg/m² and MHO was defined as not meeting the MetS criteria with a BMI ≥25 kg/m².

Results

Women with MONW had a higher prevalence of stroke than those with MHO (odds ratio [OR] = 2.27, 95% confidence interval [CI]: 1.45–3.57). The prevalence of stroke increased as the number of MetS components increased. The ORs for MONW with 3, 4, and 5 MetS components were 1.95 (95% CI: 1.19–3.21), 2.49 (95% CI: 1.46–4.24) and 2.74 (95% CI: 1.39–5.40), respectively.

Conclusions

Our study findings may better emphasize the risk of stroke among more lean but unhealthy individuals, who appear healthy but may be suffering from MetS. These findings also highlight the need for stroke risk factor assessment in non-obese weight individuals.

Acute adiponectin delivery is cardioprotective in the aged female rat heart

AIM

The aged, post-menopausal female heart is characterized by reduced ischemic tolerance, and few therapies currently exist to limit ischemic damage. Adiponectin (APN), a cytokine produced in adipose tissue, limits infarct size and improves functional recovery after ischemia/reperfusion injury in adult hearts. The aim of the present study was to extend these previous studies and determine the cardioprotective efficacy of APN treatment in aged female rats.

METHODS

Hearts were isolated from adult (age 6-7 months; n = 10), aged (age 23 months; n = 14) and aged ovariectomized (n = 10) female rats, and subjected to ischemia/reperfusion injury. On ischemia, hearts were infused with 9 μg of APN or vehicle. Adiponectin receptor 1, adiponectin receptor 2 and adenosine monophosphate-dependent kinase (AMPK) were assessed by western blotting, tumor necrosis factor-α and nicotinamide adenine dinucleotide phosphate oxidase levels by real time polymerase chain reaction. Non-reducing western blotting for APN multimers in visceral adipose was also carried out.

RESULTS

APN infusion successfully improved post-ischemic left ventricular developed pressure (∼10-15%) and attenuated the rise in end diastolic pressure in all groups (P < 0.05). With ischemia/reperfusion injury, phospho-AMPK increased in all groups with additive effects of APN on increasing phospho-AMPK abundance in aged ovary-intact female rats only (P < 0.001). Age-associated increases in pre-ischemic tumor necrosis factor-α mRNA were unaffected by APN, whereas nicotinamide adenine dinucleotide phosphate oxidase 2 mRNA levels were attenuated by APN in adult and aged ovariectomized female rats. An age-associated decrease in cardiac adiponectin receptor 2 was observed in conjunction with elevated high molecular weight APN in adipose.

CONCLUSIONS

The present data suggest that APN might be a relevant therapy for protecting the aging female heart, albeit through divergent mechanisms that are likely influenced by age-associated estrogen availability.

The potential of adipokines as therapeutic agents for cardiovascular disease

Adipose tissue functions as an endocrine organ by producing bioactive secretory proteins, also known as adipokines, that can directly act on nearby or remote organs. Most of the adipokines are upregulated by obese conditions, and typically promote obese complications. In contrast, some adipokines, such as adiponectin, CTRP9 and omentin, are downregulated in obese states. These factors exert salutary actions on obesity-linked cardiovascular disorders. In this review, we focus on the significance of adiponectin, CTRP9 and omentin as therapeutic agents for cardiovascular disease.

Time-dependent changes of plasma adiponectin concentration in relation to coronary microcirculatory function in patients with acute myocardial infarction treated by primary percutaneous coronary intervention

BACKGROUND AND PURPOSE

To analyze plasma adiponectin kinetics in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (pPCI) and its association with coronary flow reserve (CFR), an index of coronary microcirculatory function.

METHODS

A total of 96 consecutive patients with the first anterior STEMI treated by pPCI without heart failure were included. CFR was assessed on the 7th day after pPCI. Plasma adiponectin was measured on admission before pPCI, and on the 2nd and 7th day after pPCI.

RESULTS

Adiponectin concentration was the highest on admission, declined to the lowest level on the 2nd day, and rose on the 7th day remaining below admission values. Impaired coronary microcirculatory function (CFR<2) was observed in 41% of the patients. Adiponectin concentrations significantly positively correlated with CFR, and the strongest correlation was with the 2nd day adiponectin (r=0.489, p<0.001). In multivariate models, adiponectin concentrations were independent predictors of impaired CFR [on admission: odds ratio (OR) 0.175, confidence interval (CI): 0.047-0.654, p=0.010; 2nd day: OR 0.146, 95% CI: 0.044-0.485, p=0.002; 7th day: OR 0.198, CI: 0.064-0.611, p=0.005]. The best power to predict impaired CFR was the 2nd day adiponectin. Delta values of adiponectin (differences between adiponectin concentrations) did not correlate with CFR.

CONCLUSIONS

In patients with the first anterior STEMI treated by pPCI plasma adiponectin concentrations before and after pPCI are strongly associated with CFR. Our results support the hypothesis that low adiponectin, especially during the early post-pPCI period, carries the risk for impaired coronary microcirculatory function in STEMI patients.

Increased myocardial ischemia-reperfusion injury in renal failure involves cardiac adiponectin signal deficiency

Plasma levels of adiponectin (APN) are significantly increased in patients with renal dysfunction and are inversely related to the risk of cardiovascular mortality. The present study was designed to determine the role of APN in myocardial ischemia-reperfusion (MI/R) injury in mice with renal failure and delineate the underlying mechanisms. Renal failure was induced by subtotal nephrectomy (SN). Human recombinant globular domain of adiponectin (gAd) or full-length adiponectin (fAd) was administered via intraperitoneal injection once daily for 7 consecutive days after SN, and in vivo MI/R was introduced 3 wk later. Both plasma and urinary levels of APN increased significantly in SN mice. Compared with sham-operated mice, cardiac function was significantly depressed, and myocardial infarct size and apoptosis increased in SN mice following MI/R. The aggravated MI/R injury was further intensified in APN-knockout mice and markedly ameliorated by treatment with gAd but not fAd. Moreover, SN increased myocardial NO metabolites, superoxide, and their cytotoxic reaction product peroxynitrite, upregulated inducible NO synthase expression, and decreased endothelial NOS phosphorylation. In addition, SN mice also exhibited reduced APN receptor-1 (AdipoR1) expression and AMPK activation. All these changes were further amplified in the absence of APN but reversed by gAd treatment. The present study demonstrates that renal dysfunction increases cardiac susceptibility to ischemic-reperfusion injury, which is associated with downregulated APN/AdipoR1/AMPK signaling and increased oxidative/nitrative stress in local myocardium, and provides the first evidence for the protective role of exogenous supplement of gAd on MI/R outcomes in renal failure.

Adiponectin and the cardiometabolic syndrome: an epidemiological perspective

Adiponectin is an adipocyte-derived plasma protein with cardio-vasculo-protective and anti-diabetic properties. Plasma adiponectin levels are low in patients with the cardiometabolic syndrome (a cluster of multiple risk factors based on visceral fat accumulation). Routine measurement of plasma adiponectin may be useful to encourage life-style changes.

Retinol-binding protein 4 levels and susceptibility to ischaemic events in men

BACKGROUND

Many efforts in cardiovascular medicine have been focused in the identification of patients at risk of developing an acute ischaemic event. Biomarker discovery studies have become an essential research area, being proteomic technologies an excellent tool for biomarker identification. By applying proteomic approaches, we have detected changes in retinol-binding protein 4 (RBP4) in acute new-onset myocardial infarction patients (AMI) and in high-risk patients with heterozygous familial hypercholesterolaemia (FH).

MATERIALS AND METHODS

Differential serum proteome was analysed by two-dimensional electrophoresis and MALDI-TOF/TOF. Validation studies were performed by ELISA, and functional effects of RBP4 were tested in cell culture experiments.

RESULTS

Retinol-binding protein 4 proteomic characterization depicted two spots (pI = 5·4;Mw = 23·01/22·78 kDa) with decreased intensity in AMI patients. Total serum RBP4 levels were decreased in AMI patients (N = 68) compared with controls (N = 132; P < 0·0001). RBP4 was also decreased in FH patients who had an ischaemic event 2 years (±0·3) after their inclusion compared with FH patients without any cardiovascular episode at follow-up (P < 0·001; N = 187). In both cases, changes were limited to men. RBP4 induced a significant increase in eNOS expression in human endothelial vascular cells and in prostaglandin I2 release in coronary vascular smooth muscle cells.

CONCLUSIONS

We show decreased serum RBP4 levels in men in the acute phase of AMI, being this decrease already detected in men with FH previous to the presentation of an ischaemic event. The decrease in RBP4 levels could confer an increased susceptibility to the precipitation of an ischaemic event that could be mediated by the decrease in its vasculoprotective properties through NO and PGI2 .

Cardiometabolic effects of adiponectin

Over the past two decades, adiponectin has been studied in more than eleven thousand publications. A classical adipokine, adiponectin was among the first factors secreted from adipose tissue that were found to promote metabolic function. Circulating levels of adiponectin consistently decline with increasing body mass index. Clinical and basic science studies have identified adiponectin's cardiovascular-protective actions, providing a mechanistic link to the increased incidence of cardiovascular disease in obese individuals. While progress has been made in identifying receptors essential for the metabolic actions of adiponectin (AdipoR1 and AdipoR2), few studies have examined the receptor-mediated signaling pathways in cardiovascular tissues. T-cadherin, a GPI-anchored adiponectin-binding protein, was recently identified as critical for the cardiac-protective and revascularization actions of adiponectin. Adiponectin is abundantly present on the surfaces of vascular and muscle tissues through a direct interaction with T-cadherin. Consistent with this observation, adiponectin is absent from T-cadherin-deficient tissues. Since T-cadherin lacks an intracellular domain, additional studies would further our understanding of this signaling pathway. Here, we review the diverse cardiometabolic actions of adiponectin.

Impact of adiponectin and leptin on long-term adverse events in Japanese patients with acute myocardial infarction. Results from the Nagoya Acute Myocardial Infarction Study (NAMIS)

BACKGROUND

Low adiponectin levels and high leptin levels are associated with a high incidence of developing cardiovascular disease. However, the relationship between the levels of these adipokines and the development of adverse events after acute myocardial infarction (AMI) remains unclear.

METHODS AND RESULTS

This study enrolled 724 Japanese subjects with AMI who underwent successful emergency percutaneous coronary intervention (PCI). Their serum adiponectin and leptin levels were measured 7 days after AMI onset. There were 63 adverse events during the 3-year follow-up. The levels of adiponectin and leptin and the leptin to adiponectin ratio, were significantly associated with adverse events [hazard ratio 2.08 (95% confidence interval (CI) 1.33-3.24), P=0.001; hazard ratio 0.62 (95% CI 0.43-0.90), P=0.012; hazard ratio 0.59 (95% CI 0.45-0.76), P<0.001, respectively]. The leptin to adiponectin ratio remained a significant independent predictor of adverse events during long-term follow-up in a multivariable analysis [adjusted hazard ratio 0.60 (95% CI 0.43-0.83), P=0.002].

CONCLUSIONS

Higher adiponectin and lower leptin levels are associated with a high incidence of adverse events in Japanese patients after AMI, and the leptin to adiponectin ratio independently predicts prognosis after AMI.

Relation of serum adiponectin levels to number of traditional atherosclerotic risk factors and all-cause mortality and major adverse cardiovascular events (from the Copenhagen City Heart Study)

Adiponectin exerts anti-inflammatory and antiatherogenic effects and appears to protect against arteriosclerosis. Accordingly, an association between low concentrations of plasma adiponectin and cardiovascular (CV) disease has been demonstrated in several studies. In contrast, elevated plasma adiponectin has been associated with increased mortality and an increasing number of major adverse CV events (MACE). Because of these conflicting results, the true role of adiponectin remains to be elucidated. In the Copenhagen City Heart Study, we prospectively followed up 5,624 randomly selected men and women from the community without CV disease. Plasma adiponectin was measured at the beginning of the study. The median follow-up time was 7.8 years (interquartile range 7.3 to 8.3). The end point was all-cause mortality (n = 801), and the combined end point was MACE, consisting of CV mortality or nonfatal myocardial infarction or ischemic stroke (n = 502). High adiponectin was inversely associated with an increasing number of traditional CV risk factors (p <0.0001). The geometric mean adiponectin concentrations were 10.0 mg/L (95% confidence interval [CI] 9.7 to 10.4) for persons with no CV risk factors present versus 8.1 mg/L (95% CI 7.8 to 8.4) for persons with 4 CV risk factors. After adjustment for confounding risk factors by Cox regression analysis, adiponectin remained an independent predictor of death and MACE. The hazard ratio for each increase in adiponectin of 5 mg/L for death and MACE was 1.20 (95% CI 1.14 to 1.27; p <0.0001) and 1.14 (95% CI 1.05-1.23; p <0.0001), respectively. In conclusion, an increasing number of risk factors for CV disease is associated with decreased plasma adiponectin. High plasma adiponectin independently predicted death and MACE in a large community-based population. These results have confirmed the dual expression indicated by previous studies.

Differential regulation of TNF receptor 1 and receptor 2 in adiponectin expression following myocardial ischemia

BACKGROUND

In vitro experiments demonstrate that adiponectin, a cardioprotective cytokine, is inhibited by tumor necrosis factor-alpha (TNFα). However, the role of TNFα in post-myocardial infarction (post-MI) adiponectin reduction remains unclear. More importantly, the TNF receptor type (TNFR1 or TNFR2) responsible for TNFα-mediated suppression of adiponectin production is unknown. The current study determined the role of TNFα in post-myocardial infarction (post-MI) adiponectin reduction, and identified the receptor type responsible for TNFα-mediated suppression of adiponectin production.

METHODS AND RESULTS

Adult male wild type (WT) and three knockout variety (TNFα(-/-), TNFR1(-/-), and TNFR2(-/-)) mice were subjected to MI via coronary artery occlusion. Histological and biochemical analyses were performed 3 and 7days post-MI. In WT mice, MI significantly increased plasma TNFα, reduced adipocyte adiponectin mRNA, and decreased plasma adiponectin levels. TNFα deletion had no significant effect upon basal adiponectin level, and partially restored adiponectin expression/production post-MI (P<0.01 vs. WT). Basal adiponectin levels were significantly increased in TNFR1(-/-) (P<0.05 vs. WT), and unchanged in TNFR2(-/-) mice. Importantly, suppressed adiponectin expression/production by MI or TNFα administration was markedly decreased by TNFR1 deletion (P<0.01 vs. WT), but exacerbated by TNFR2 deletion (P<0.05 vs. WT). Mechanistically, TNFR1 knockout significantly inhibited, whereas TNFR2 knockout further enhanced TNFα-induced mRNA and protein expression of ATF3, a transcriptional factor known to significantly inhibit adiponectin expression.

CONCLUSION

Our study demonstrates that TNFα overproduction is responsible for reduced adiponectin expression/production following MI. Furthermore, we show that TNFR1/TNFR2 exerts opposite effects upon adiponectin expression/production via differential regulation of ATF3.

Overweight, hypertension and renal dysfunction in adulthood of neonatally overfed rats

Accelerated growth in early infancy has been associated with later cardiovascular and metabolic diseases. We investigated the influence of overnutrition during neonatal periods on the development of renal pathophysiological changes in adult offspring rats. Three or 10 male pups per mother were assigned to either the small litter (SL) or normal litter (NL) control groups during the first 21 days of life. The effects of early postnatal overnutrition on body weight, blood pressure and renal changes were determined at 3 and 6 months. Pups in the SL group weighed more than controls between 7 days and 6 months of age (P<.05). In the SL group, serum creatinine levels were higher at 3 and 6 months (P<.05), and at 6 months, blood pressure levels were higher than those of the controls (P<.05). The number of ED-1 positive macrophages in renal cortex and glomerulosclerosis index increased in the SL group at 3 and 6 months (P<.05). Additionally, cortical apoptotic cells increased in the SL group at 6 months (P<.05). Immunoblotting and immunohistochemistry showed that matrix metalloproteinase (MMP)-9 protein expressions decreased and tissue inhibitor of MMP-1, tumor necrosis factor-α, osteopontin and adiponectin expressions increased in the SL group at 3 months (P<.05). However, at 6 months, MMP-9 expression was elevated, and osteopontin expression remained elevated in the SL group (P<.05). Early postnatal overfeeding can lead to lasting overweight, hypertension and renal dysfunction and place a greater burden on the kidney.

Endogenous bioactive peptides as potential biomarkers for atherosclerotic coronary heart disease

Cardiovascular disease is the leading cause of death worldwide, with high medical costs and rates of disability. It is therefore important to evaluate the use of cardiovascular biomarkers in the early diagnosis of coronary artery disease (CAD). We have screened a variety of recently identified bioactive peptides candidates in anticipation that they would allow detection of atherosclerotic CAD. Especially, we have focused on novel anti-atherogenic peptides as indicators and negative risk factors for CAD. In vitro, in vivo and clinical studies indicated that human adiponectin, heregulin-β₁, glucagon-like peptide-1 (GLP-1), and salusin-α, peptides of 244, 71, 30, and 28 amino acids, respectively, attenuate the development and progression of atherosclerotic lesions by suppressing macrophage foam cell formation via down-regulation of acyl-coenzyme A: cholesterol acyltransferase-1. Circulating levels of these peptides in the blood are significantly decreased in patients with CAD compared to patients without CAD. Receiver operating characteristic analyses showed that salusin-α is a more useful biomarker, with better sensitivity and specificity, compared with the others for detecting CAD. Therefore, salusin-α, heregulin-β₁, adiponectin, and/or GLP-1, alone or in various combinations, may be useful as biomarkers for atherosclerotic CAD.

Differential proteomic distribution of TTR (pre-albumin) forms in serum and HDL of patients with high cardiovascular risk

Inflammation is a common condition contributing to cardiovascular disease progression which leads to clinical manifestations such as acute myocardial infarction (AMI). By applying a proteomic expression profiling approach we have investigated changes in transthyretin (TTR) in AMI-patients and its distribution patterns in HDL samples of patients with high cardiovascular risk, such as those with familiar hypercholesterolemia (FH).

METHODS AND RESULTS

The characterization by bidimensional electrophoresis (2-DE), followed by mass-spectrometry (MALDI-TOF) of serum samples revealed changes in the intensity of the TTR spot with a pI of 5.6 and a Mw of 42kDa (tTTR) between AMI-patients in association to diabetic dyslipemia. Serum TTR levels, determined by commercial ELISA, were significantly lower (p<0.0001) in AMI-patients (n=39) and FH-patients (n=100) than in healthy controls (n=60). Western blot and 2-DE analysis showed a differential distribution profile of TTR forms between serum, where 3 TTR forms of 42 (tTTR), 28 (dTTR), and 14kDa (mTTR) were detected, and HDL samples, where only mTTR was present.

CONCLUSIONS

Our results demonstrate alterations in TTR proteomic profile in relation to the clustering of risk factors which seems to highlight the implication of TTR in cardiovascular risk. The significant differences in TTR between serum (tTTR) and HDL (mTTR) underscore the importance of TTR-forms in the circulation and deserve further investigation to understand their function.

Cardiac biomarkers in acute myocardial infarction

Each year, a large number of patients are seen in the Emergency Department with presentations necessitating investigation for possible acute myocardial infarction. Patients can be stratified by symptoms, risk factors and electrocardiogram results but cardiac biomarkers also have a prime role both diagnostically and prognostically. This review summarizes both the history of cardiac biomarkers as well as currently available (established and novel) assays. Cardiac troponin, our current "gold standard" biomarker criterion for the diagnosis of myocardial infarction has high sensitivity and specificity for this diagnosis and therapies instituted in patients with elevated troponin have been shown to influence outcomes. Other markers of myocardial necrosis, inflammation and neurohormonal activity have also been shown to have either diagnostic or prognostic utility, but none have been shown to be superior to troponin. The measurement of multiple biomarkers and the use of point of care markers may accelerate current diagnostic protocols for the assessment of such patients.

Beneficial effect of combination therapy comprising angiotensin II receptor blocker plus calcium channel blocker on plasma adiponectin levels

The study aim was to examine the effect of combination therapy comprising angiotensin receptor blocker plus calcium antagonist on post-treatment plasma adiponectin levels compared to pretreatment levels. There was a significant gender difference in the relationship between preadiponectin level and age. In the search for contributing factors for treatment-based changes in adiponectin levels, these effects of gender and age were considered in statistical analysis. The adiponectin level in the combination therapy group was further increased compared to that in each of the monotherapy groups, despite there being no significant difference in antihypertensive effect, indicating that the combined medication provided an effect beyond that of lowering blood pressure.

Impact of a single intracoronary administration of adiponectin on myocardial ischemia/reperfusion injury in a pig model

BACKGROUND

Adiponectin plays a protective role in the development of obesity-linked disorders. We demonstrated that adiponectin exerts beneficial actions on acute ischemic injury in mice hearts. However, the effects of adiponectin treatment in large animals and its feasibility in clinical practice have not been investigated. This study investigated the effects of intracoronary administration of adiponectin on myocardial ischemia-reperfusion (I/R) injury in pigs.

METHODS AND RESULTS

The left anterior descending coronary artery was occluded in pigs for 45 minutes and then reperfused for 24 hours. Recombinant adiponectin protein was given as a bolus intracoronary injection during ischemia. Cardiac functional parameters were measured by a manometer-tipped catheter. Apoptosis was evaluated by terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling staining. Tumor necrosis factor-alpha and interleukin-10 transcripts were analyzed by real-time polymerase chain reaction. Serum levels of derivatives of reactive oxygen metabolites and biological antioxidant potential were measured. Adiponectin protein was determined by immunohistochemical and Western blot analyses. Intracoronary administration of adiponectin protein led to a reduction in myocardial infarct size and improvement of left ventricular function in pigs after I/R. Injected adiponectin protein accumulated in the I/R-injured heart. Adiponectin treatment resulted in decreased tumor necrosis factor-alpha and increased interleukin-10 mRNA levels in the myocardium after I/R. Adiponectin-treated pigs had reduced apoptotic activity in the I/R-injured heart and showed increased biological antioxidant potential levels and decreased derivatives of reactive oxygen metabolite levels in the blood stream after I/R.

CONCLUSIONS

These data suggest that adiponectin protects against I/R injury in a preclinical pig model through its ability to suppress inflammation, apoptosis, and oxidative stress. Administration of intracoronary adiponectin could be a useful adjunctive therapy for acute myocardial infarction.

Mechanisms linking obesity, chronic kidney disease, and fatty liver disease: the roles of fetuin-A, adiponectin, and AMPK

Obesity is a risk factor for chronic kidney disease (CKD) and nonalcoholic fatty liver disease (NAFLD). Recent studies identify mechanisms common to both diseases linked through an interorgan communication orchestrated by fetuin-A and adiponectin. In liver and kidney, the energy sensor 5'-AMP activated protein kinase (AMPK) is pivotal to directing podocytes and hepatocytes to compensatory and potentially deleterious pathways, leading to inflammatory and profibrotic cascades culminating in end-organ damage. Regulation of these early upstream pathways may provide new therapeutic targets for these increasingly common sequelae of obesity.

Lipotoxicity in the heart

Obesity and insulin resistance are associated with ectopic lipid deposition in multiple tissues, including the heart. Excess lipid may be stored as triglycerides, but are also shunted into non-oxidative pathways that disrupt normal cellular signaling leading to organ dysfunction and in some cases apoptosis, a process termed lipotoxicity. Various pathophysiological mechanisms have been proposed to lead to lipotoxic tissue injury, which might vary by cell type. Specific mechanisms by which lipotoxicity alter cardiac structure and function are incompletely understood, but are beginning to be elucidated. This review will focus on mechanisms that have been proposed to lead to lipotoxic injury in the heart and will review the state of knowledge regarding potential causes and correlates of increased myocardial lipid content in animal models and humans. We will seek to highlight those areas where additional research is warranted.

Is adiponectin associated with acute myocardial infarction in Iranian non obese patients?

BACKGROUND

Adiponectin is an adipose tissue-derived mediator with significant anti-atherogenic properties. A few studies were done in acute phase of myocardial infarction especially in non obese patients. We design a study to investigate the association between adiponectin concentration and acute phase of myocardial infarction in non obese patients.

METHODS

This case-control study was done in Paymaneah Hospital (Jahrom, Iran) from Feb 2007 to May 2008. Plasma adiponectin levels were measured in 43 patients with AMI (mean age: 62.7 +/- 13.3 years, male: 67.4%) at the first 24 hours of admission and 43 normal controls (mean age: 62.1 +/- 12.3 years, male: 55.8%) matched for age, sex and other CAD risk factors.

RESULTS

Adiponectin levels in patients with AMI (3.36 microg/mL) were significantly lower than that of the control group (5.03 microg/mL) (p < 0.0001). Lower adiponectin were independently associated with higher risk of AMI (odds ratio = 8.97; 95% CIs: 2.3-34.5; p = 0.001). Adiponectin levels negatively correlated with triglyceride (r = -0.46, p = 0.002) and total cholesterol (r = -0.32, p = 0.03) in the case group and with body mass index (BMI) in control subjects.

CONCLUSION

The present study showed that adiponectin was associated with AMI in non obese patients but it is not related to sex, age and other CAD risk factors.

Adiponectin: from obesity to cardiovascular disease

Adiponectin is an adipokine whose biosynthesis is deranged in obesity and diabetes mellitus, predisposing to atherosclerosis. Evidence suggests that adiponectin has anti-atherogenic properties by improving endothelial function and having anti-inflammatory effects in the vascular wall. In addition, adiponectin modifies vascular intracellular redox signalling and exerts indirect antioxidant effects on human myocardium. However, its clinical role in cardiovascular disease is obscure. Adiponectin's positive prognostic value in coronary artery disease had been widely supported over the last years, but this view has been questioned recently. High adiponectin levels are paradoxically associated with poorer prognosis in heart failure syndrome. These controversial findings seem surprising as adiponectin has been viewed overall as an anti-atherogenic molecule. Therefore, any certain conclusion about adiponectin's role in cardiovascular disease seems premature. Despite the rapidly accumulating literature on this adipokine, it is still unclear whether adiponectin is a key mediator or a bystander in cardiovascular disease. It is still uncertain whether adiponectin levels have any clinical significance for risk stratification in cardiovascular disease or they just reflect the activation of complex and opposing underlying mechanisms. Circulating adiponectin levels should be interpreted with caution, as they may have completely different prognostic value, depending on the underlying disease state.

The link between obesity and albuminuria: adiponectin and podocyte dysfunction

With the recent rise in the prevalence of obesity worldwide, obesity-related albuminuria is now being recognized as a critical risk factor for cardiovascular disease. However, there is an urgent need for a better understanding of this association. Recent clinical studies suggest that the adipocyte hormone adiponectin may play a key role in the development of obesity-related albuminuria. Moreover, studies with the adiponectin knockout mouse indicate that adiponectin can regulate podocyte function and thus contribute to the initial development of albuminuria. Future studies examining renal adipocyte cell biology are needed to develop preventive and therapeutic strategies for combatting the complications of obesity.

Plasma adiponectin and resistin levels as predictors of mortality in patients with acute myocardial infarction: data from infarction prognosis study registry

BACKGROUND

Adiponectin and resistin, which have counteracting effects, are suggested to be associated with inflammation and atherosclerosis. The relationship between their levels and prognosis in high risk patients is, however, still unclear. The aim of this study was to evaluate the prognostic values of these adipokines in patients with acute myocardial infarction (MI).

METHODS

Adiponectin and resistin levels were measured at acute phase of MI in 397 consecutive patients. All patients were followed-up for the occurrence of all-cause and cardiovascular mortalities. Predictors for all-cause and cardiovascular mortalities were analyzed by Cox proportional hazard model.

RESULTS

During the mean follow-up period of 12 months, 28 (7.1%) patients died. Unadjusted all-cause mortality rate was significantly higher in patients with high tertiles of adiponectin (P=0.002) and resistin (P=0.002) levels. After controlling of clinical and laboratory variables, age [95% confidence interval (CI): 1.20-2.83, P=0.006], adiponectin (95% CI: 1.01-1.22, P=0.040), resistin (95% CI: 1.06-2.33, P=0.025), and statin use (95% CI: 0.15-0.83, P=0.017) were found to be independent predictors of all-cause mortality. For cardiovascular mortality, only age (95% CI: 1.33-3.25, P=0.001) and renal insufficiency (95% CI: 1.52-12.22, P=0.006) were independent predictors.

CONCLUSION

High plasma adiponectin and resistin levels were predictors for all-cause mortality independent of other risk factors in patients with acute MI. These results confirmed and extended the positive correlations between these adipokines and mortality to a population consisting exclusively of MI.

Usefulness of adiponectin to predict myocardial salvage following successful reperfusion in patients with acute myocardial infarction

Adiponectin is an adipose-derived plasma protein that demonstrates beneficial actions on myocardial injury under ischemic conditions. Circulating endothelial progenitor cells are reported to associate with rescue of cardiac damage after acute myocardial infarction (AMI). We examined whether circulating adiponectin level affects myocardial function and injury in patients with AMI. A total of 48 patients who underwent successful reperfusion treatment after AMI were enrolled. Cardiac function and perfusion defect were assessed by scintigraphic images of iodine-123 beta-methyl iodophenyl pentadecanoic acid in the acute phase and technetium-99m tetrofosmin in the long-term phase. Plasma adiponectin levels were measured by enzyme-linked immunosorbent assay at day 7 after AMI. Plasma adiponectin levels associated positively with myocardial salvage index representing the proportion of initial perfusion defect rescued by reperfusion and recovery of ejection fraction in the long-term phase and negatively with final infarct size. A positive correlation was also observed between adiponectin levels and number of circulating CD34(+) cells as determined by flow cytometry and between myocardial salvage index and recovery of ejection fraction independently associated with circulating CD34(+) cell levels. In conclusion, plasma adiponectin levels predict improvement of cardiac damage and function after reperfusion therapy in patients with AMI, suggesting that adiponectin could serve as a biomarker for assessment of myocardial injury after AMI.

Metabolic syndrome increases the risk of ischemic stroke in women

BACKGROUND

Metabolic syndrome is a characterized by a cluster of cardiovascular risk factors, including visceral obesity, insulin resistance, dyslipidemia, and hypertension. The criteria for diagnosing metabolic syndrome differ among ethnic groups, due in part to differences in eating habits and body build. Little is known about the relationship between metabolic syndrome and ischemic stroke in Asian countries. The aim of this study was to investigate the relationship between metabolic syndrome and first-time ischemic strokes.

SUBJECTS & METHODS

Study subjects were 1,493 Japanese adults aged 55 years-old or older with no diabetes mellitus, no history of stroke and no neurological abnormalities, who participated in a voluntary neurological health screening at the Institute of Shimane Health Science, Japan (767 men, 62.0 +/- 5.9 years old at entry and 726 women, 61.8 +/- 5.1 years old at entry). All subjects were given an annual clinical stroke questionnaire. Clinical details of patients who reported strokes were confirmed with the attending physicians. Each subject was evaluated for an average of 6.4 +/- 3.8 years. Metabolic syndrome was defined using the modified criteria for Japanese population published in April 2005.

RESULTS

Metabolic syndrome was diagnosed in 11.0% of men and 1.1% of women. Adjusting for age and smoking, female subjects with metabolic syndrome had a 23.1-fold increased risk of suffering ischemic strokes [95% confidence interval (CI), 2.7-196], whereas metabolic syndrome did not increase the risk of ischemic stroke in men.

CONCLUSIONS

Metabolic syndrome is more likely to influence a risk for ischemic stroke in women than in men.