Adiponectin level and left ventricular hypertrophy in Japanese men

Changes in adiponectin system after ventricular assist device in pediatric heart failure

Background

Ventricular assist device (VAD) implant represents a therapeutic option for pediatric patients with end-stage heart failure (HF). Heart unloading by VAD can modify several molecular pathways underlying cardiac function in HF. Among them, the potential role of microRNA (miRNAs) in response to VAD implant is emerging. This study was aimed at investigating in HF pediatric patients the effect of VAD-modified miRNAs on the adiponectin (ADPN) system, known to exert cardioprotective actions.

Methods

ADPN was measured in plasma samples obtained from HF children, before and 1 month after VAD implant, and from healthy control children. miRNA profile and molecules belonging to ADPN system were determined in cardiac biopsies collected at the time of VAD implantation (pre-VAD) and at the moment of heart transplant (post-VAD). An in vitro study using HL-1 cell line was performed to verify the regulatory role of the VAD-modified miRNA on the ADPN system.

Results

VAD implant did not affect circulating and cardiac levels of ADPN, but increased the cardiac mRNA expression of ADPN receptors, including AdipoR1, AdipoR2, and T-cad. AdipoR2 and T-cad were inversely related to the VAD-modified miRNA levels. The in vitro study confirmed the regulatory role of miR-1246 and miR-199b-5p on AdipoR2, and of miR-199b-5p on T-cad.

Conclusions

These data suggest that VAD treatment could regulate the expression of the cardioprotective ADPN system by epigenetic mediators, suggesting that miRNAs have a potential role as therapeutic targets to improve cardiac function in HF pediatric patients.

The Role of Adipokines in Health and Disease

Adipokines are cell-signaling proteins secreted by adipose tissue that has been related to a low-grade state of inflammation and different pathologies. The present review aims to analyze the role of adipokines in health and disease in order to understand the important functions and effects of these cytokines. For this aim, the present review delves into the type of adipocytes and the cytokines produced, as well as their functions; the relations of adipokines in inflammation and different diseases such as cardiovascular, atherosclerosis, mental diseases, metabolic disorders, cancer, and eating behaviors; and finally, the role of microbiota, nutrition, and physical activity in adipokines is discussed. This information would allow for a better understanding of these important cytokines and their effects on body organisms.

Potential clinical biomarkers and perspectives in diabetic cardiomyopathy

Diabetic cardiomyopathy (DCM) is a serious cardiovascular complication and the leading cause of death in diabetic patients. Patients typically do not experience any symptoms and have normal systolic and diastolic cardiac functions in the early stages of DCM. Because the majority of cardiac tissue has already been destroyed by the time DCM is detected, research must be conducted on biomarkers for early DCM, early diagnosis of DCM patients, and early symptomatic management to minimize mortality rates among DCM patients. Most of the existing implemented clinical markers are not very specific for DCM, especially in the early stages of DCM. Recent studies have shown that a number of new novel markers, such as galactin-3 (Gal-3), adiponectin (APN), and irisin, have significant changes in the clinical course of the various stages of DCM, suggesting that we may have a positive effect on the identification of DCM. As a summary of the current state of knowledge regarding DCM biomarkers, this review aims to inspire new ideas for identifying clinical markers and related pathophysiologic mechanisms that could be used in the early diagnosis and treatment of DCM.

Effects of caloric overload before caloric restriction in the murine heart

The beneficial effects of caloric restriction (CR) against cardiac aging and for prevention of cardiovascular diseases are numerous. However, to our knowledge, there is no scientific evidence about how a high-calorie diet (HCD) background influences the mechanisms underlying CR in whole heart tissue (WHT) in experimental murine models. In the current study, CR-treated mice with different alimentary backgrounds were subjected to transthoracic echocardiographic measurements. WHT was then analyzed to determine cardiac energetics, telomerase activity, the expression of energy-sensing networks, tissue-specific adiponectin, and cardiac precursor/cardiac stem cell markers. Animals with a balanced diet consumption before CR presented marked cardiac remodeling with improved ejection fraction (EF) and fractional shortening (FS), enhanced OXPHOS complex I, III, and IV, and CKMT2 enzymatic activity. Mice fed an HCD before CR presented moderate changes in cardiac geometry with diminished EF and FS values, but improved OXPHOS complex IV and CKMT2 activity. Differences in cardiac remodeling, left ventricular systolic/diastolic performance, and mitochondrial energetics, found in the CR-treated mice with contrasting alimentary backgrounds, were corroborated by inconsistencies in the expression of mitochondrial-biogenesis-related markers and associated regulatory networks. In particular, disruption of eNOS and AMPK -PGC-1α-mTOR-related axes. The impact of a past habit of caloric overload on the effects of CR in the WHT is a scarcely explored subject that requires deeper study in combination with analyses of other tissues and organs at higher levels of organization within the organ system. Such research will eventually lead to the development of preventative and therapeutic strategies to promote health and longevity.

Association of Adiponectin, Leptin and Resistin Plasma Concentrations with Echocardiographic Parameters in Patients with Coronary Artery Disease

The imbalanced network of adipokines may contribute to the development of systemic low-grade inflammation, metabolic diseases and coronary artery disease (CAD). In the last decade, three classic adipokines—adiponectin, leptin and resistin—have been of particular interest in studies of patients with CAD due to their numerous properties in relation to the cardiovascular system. This has directed our attention to the association of adipokines with cardiac structure and function and the development of heart failure (HF), a common end effect of CAD. Thus, the purpose of this study was to analyse the associations of plasma concentrations of adiponectin, leptin and resistin with parameters assessed in the echocardiographic examinations of CAD patients. The presented study enrolled 167 Caucasian patients (133 male; 34 female) with CAD. Anthropometric, echocardiographic and basic biochemical measurements, together with plasma concentrations of adiponectin, leptin and resistin assays, were performed in each patient. Adiponectin concentrations were negatively associated with left ventricular ejection fraction (LVEF) and shortening fraction (LVSF), and positively associated with mitral valve E/A ratio (E/A), left ventricular end-diastolic volume (LVEDV), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter LVESD, and left atrium diameter (LAD). Resistin concentrations were negatively associated with E/A. Leptin concentrations, although correlated with HF severity assessed by the New York Heart Association (NYHA) Functional Classification, were not independently associated with the echocardiographic parameters of cardiac structure or function. In conclusion, adiponectin and resistin, but not leptin, are associated with the echocardiographic parameters of cardiac remodelling and dysfunction. These associations suggest that adiponectin and resistin might be involved in mechanisms of cardiac remodelling or compensative response. We also suggest the possible benefits of adiponectin and resistin level measurements in the monitoring of patients with CAD.

Adiponectin: Structure, Physiological Functions, Role in Diseases, and Effects of Nutrition

Adiponectin (a protein consisting of 244 amino acids and characterized by a molecular weight of 28 kDa) is a cytokine that is secreted from adipose tissues (adipokine). Available evidence suggests that adiponectin is involved in a variety of physiological functions, molecular and cellular events, including lipid metabolism, energy regulation, immune response and inflammation, and insulin sensitivity. It has a protective effect on neurons and neural stem cells. Adiponectin levels have been reported to be negatively correlated with cancer, cardiovascular disease, and diabetes, and shown to be affected (i.e., significantly increased) by proper healthy nutrition. The present review comprehensively overviews the role of adiponectin in a range of diseases, showing that it can be used as a biomarker for diagnosing these disorders as well as a target for monitoring the effectiveness of preventive and treatment interventions.

Angiopoietin-Like Protein 8/Leptin Crosstalk Influences Cardiac Mass in Youths With Cardiometabolic Risk: The BCAMS Study

OBJECTIVES

The link between excess adiposity and left ventricular hypertrophy is multifaceted with sparse data among youths. Given that adipokines/hepatokines may influence lipid metabolism in myocardium, we aimed to investigate the relation of the novel hepatokine angiopoietin-like protein 8 (ANGPTL8) and other adipokines with cardiac structure in a cohort of youths and explore to what extent these adipokines/hepatokines affect cardiac structure through lipids.

METHODS

A total of 551 participants (aged 15-28 years) from the Beijing Child and Adolescent Metabolic Syndrome Study (BCAMS) cohort underwent echocardiographic measurements plus a blood draw assayed for five adipokines/hepatokines including adiponectin, leptin, retinol binding protein 4, fibroblast growth protein 21 and ANGPTL8.

RESULTS

Both ANGPTL8 (β = -0.68 g/m^2.7 per z-score, P= 0.015) and leptin (β = -1.04 g/m^2.7 per z-score, P= 0.036) were significantly inversely associated with left ventricular mass index (LVMI) independent of classical risk factors. Total cholesterol and low-density lipoprotein cholesterol significantly mediated the ANGPTL8-LVMI association (proportion: 19.0% and 17.1%, respectively), while the mediation effect of triglyceride on the ANGPTL8-LVMI relationship was strongly moderated by leptin levels, significantly accounting for 20% of the total effect among participants with higher leptin levels. Other adipokines/hepatokines showed no significant association with LVMI after adjustment for body mass index.

CONCLUSIONS

Our findings suggest ANGPTL8, particularly interacting with leptin, might have a protective role in cardiac remodeling among youths with risk for metabolic syndrome. Our results offer insights into the pathogenesis of the cardiomyopathy and the potential importance of tissue-tissue crosstalk in these effects.

Mechanisms linking adipose tissue inflammation to cardiac hypertrophy and fibrosis

Adipose tissue is classically recognized as the primary site of lipid storage, but in recent years has garnered appreciation for its broad role as an endocrine organ comprising multiple cell types whose collective secretome, termed as adipokines, is highly interdependent on metabolic homeostasis and inflammatory state. Anatomical location (e.g. visceral, subcutaneous, epicardial etc) and cellular composition of adipose tissue (e.g. white, beige, and brown adipocytes, macrophages etc.) also plays a critical role in determining its response to metabolic state, the resulting secretome, and its potential impact on remote tissues. Compared with other tissues, the heart has an extremely high and constant demand for energy generation, of which most is derived from oxidation of fatty acids. Availability of this fatty acid fuel source is dependent on adipose tissue, but evidence is mounting that adipose tissue plays a much broader role in cardiovascular physiology. In this review, we discuss the impact of the brown, subcutaneous, and visceral white, perivascular (PVAT), and epicardial adipose tissue (EAT) secretome on the development and progression of cardiovascular disease (CVD), with a particular focus on cardiac hypertrophy and fibrosis.

The Role of Cardiac T-Cadherin in the Indicating Heart Failure Severity of Patients with Non-Ischemic Dilated Cardiomyopathy

Background and objectives: T-cadherin (T-cad) is one of the adiponectin receptors abundantly expressed in the heart and blood vessels. Experimental studies show that T-cad sequesters adiponectin in cardiovascular tissues and is critical for adiponectin-mediated cardio-protection. However, there are no data connecting cardiac T-cad levels with human chronic heart failure (HF). The aim of this study was to assess whether myocardial T-cad concentration is associated with chronic HF severity and whether the T-cad levels in human heart tissue might predict outcomes in patients with non-ischemic dilated cardiomyopathy (NI-DCM). Materials and Methods: 29 patients with chronic NI-DCM and advanced HF were enrolled. Patients underwent regular laboratory investigations, echocardiography, coronary angiography, and right heart catheterization. TNF-α and IL6 in serum were detected by enzyme-linked immunosorbent assay (ELISA). Additionally, endomyocardial biopsies were obtained, and the levels of T-cad were assessed by ELISA and CD3, CD45Ro, CD68, and CD4- immunohistochemically. Mean pulmonary capillary wedge pressure (PCWP) was used as a marker of HF severity, subdividing patients into two groups: mean PCWP > 19 mmHg vs. mean PCWP < 19 mmHg. Patients were followed-up for 5 years. The study outcome was composite: left ventricular assist device implantation, heart transplantation, or death from cardiovascular causes. Results: T-cad shows an inverse correlation with the mean PCWP (rho = −0.397, p = 0.037). There is a tendency towards a lower T-cad concentration in patients with more severe HF, as indicated by the mean PCWP > 19 mmHg compared to those with mean PCWP ≤ 19 mmHg (p = 0.058). Cardiac T-cad levels correlate negatively with myocardial CD3 cell count (rho = −0.423, p = 0.028). Conclusions: Univariate Cox regression analysis did not prove T-cad to be an outcome predictor (HR = 1, p = 0.349). However, decreased T-cad levels in human myocardium can be an additional indicator of HF severity. T-cad in human myocardium has an anti-inflammatory role. More studies are needed to extend the role of T-cad in the outcome prediction of patients with NI-DCM.

Association of serum leptin and adiponectin concentrations with echocardiographic parameters and pathophysiological states in patients with cardiovascular disease receiving cardiovascular surgery

Leptin and adiponectin are important regulators of energy metabolism and body composition. Leptin exerts cardiodepressive effects, whereas adiponectin has cardioprotective effects, but several conflicting findings have been reported. The aim of the present study was to assess the relationship between serum leptin and adiponectin levels and echocardiographic parameters and pathophysiological states in patients with cardiovascular disease (CVD) receiving cardiovascular surgery. A total of 128 patients (79 males, average age 69.6 years) that had surgery for CVD including coronary artery bypass graft (CABG) and valve replacement were recruited in this study. Preoperative serum adiponectin and leptin concentrations were measured by enzyme-linked immunosorbent assay and compared with preoperative echocardiographic findings. Body fat volume and skeletal muscle volume index (SMI) were estimated using bioelectrical impedance analysis. We also measured grip strength and gait speed. Sarcopenia was diagnosed based on the recommendations of the Asian Working Group on Sarcopenia. Positive correlations were found between adiponectin and brain natriuretic peptide (BNP), age, left atrial diameter (LAD), E/e’ (early-diastolic left ventricular inflow velocity / early-diastolic mitral annular velocity), and left atrial volume index (LAVI). Negative correlations were observed between adiponectin and body mass index (BMI), estimated glomerular filtration rate (eGFR), triglyceride, hemoglobin, and albumin. Serum leptin was positively correlated with BMI, total cholesterol, triglyceride, albumin, body fat volume, and LV ejection fraction (LVEF), whereas it was negatively correlated with BNP and echocardiographic parameters (LAD, LV mass index (LVMI), and LAVI). Multiple regression analysis showed associations between log (leptin) and log (adiponectin) and echocardiographic parameters after adjusting for age, sex, and BMI. Serum adiponectin was negatively correlated with leptin, but positively correlated with tumor necrosis factor α (TNFα), an inflammatory cytokine. In males, serum leptin level had a positive correlation with skeletal muscle volume and SMI. However, adiponectin had a negative correlation with anterior mid-thigh muscle thickness, skeletal muscle volume and SMI. And, it was an independent predictive factor in males for sarcopenia even after adjusted by age. These results suggest that leptin and adiponectin may play a role in cardiac remodeling in CVD patients receiving cardiovascular surgery. And, adiponectin appears to be a marker of impaired metabolic signaling that is linked to heart failure progression including inflammation, poor nutrition, and muscle wasting in CVD patients receiving cardiovascular surgery.

Changes in Left Ventricular Mass and Geometry in the Older Adults: Role of Body Mass and Central Obesity

BACKGROUND

Left ventricular (LV) hypertrophy is an independent risk factor for cardiovascular outcomes. There are limited data about modifiable factors associated with progression of LV hypertrophy in older adults. Our objective is to describe the changes in LV mass and geometry over time in a predominantly older multiethnic cohort and to identify possible predictors of changes over time.

METHODS

We analyzed data from participants in the Northern Manhattan Study who underwent serial echocardiographic studies, comparing the baseline and the most recent echocardiograms. We recorded changes in LV mass and geometry and correlated them with baseline characteristics using linear regression models.

RESULTS

There were 826 participants (mean age, 64.2 ± 8.0 years) included in the analysis (time between measurements, 8.5 ± 2.7 years). Overall, LV mass index increased from 45.0 ± 12.7 to 50.3 ± 14.6 g/m^2.7 (P < .001). There were 548 participants (66.3%) with LV mass increase; 258 individuals (31.2%) showed worsening LV geometry. Multivariable analysis showed that change in LV mass index was independently associated with baseline LV mass index (β estimate, -17.000 [standard error, 1.508]; P < .001), hypertension (2.094 [0.816], P = .011), body mass index (0.503 [0.088], P < .001), and waist-to-hip ratio (1.031 [0.385], P = .008). Both waist-to-hip ratio and waist-to-height ratio remained significantly associated with LV mass increase even after adjusting for body mass index (P = .008 and P = .036, respectively).

CONCLUSIONS

Regardless of race/ethnicity, LV mass progressed over time in older adults. We also observed that worsening geometry was frequent. Assessment of central obesity in the older population is important because indicators of central obesity add prognostic value over body mass index for the risk of LV mass increase.

The Role of Serum Adiponectin for Outcome Prediction in Patients with Dilated Cardiomyopathy and Advanced Heart Failure

Clinical interpretation of patients' plasma adiponectin (APN) remains challenging; its value as biomarker in dilated cardiomyopathy (DCM) is equivocal. We evaluated whether circulating APN level is an independent predictor of composite outcome: death, left ventricle assist device (LVAD) implantation, and heart transplantation (HT) in patients with nonischemic DCM. 57 patients with nonischemic DCM (average LV diastolic diameter 6.85 cm, LV ejection fraction 26.63%, and pulmonary capillary wedge pressure 22.06  mmHg) were enrolled. Patients underwent echocardiography, right heart catheterization, and endomyocardial biopsy. During a mean follow-up of 33.42 months, 15 (26%) patients died, 12 (21%) patients underwent HT, and 8 (14%) patients were implanted with LVAD. APN level was significantly higher in patients who experienced study endpoints (23.4 versus 10.9 ug/ml, p = 0.01). APN was associated with worse outcome in univariate Cox proportional hazards model (HR 1.04, CI 1.02-1.07, p = 0.001) but lost significance adjusting for other covariates. Average global strain (AGS) is an independent outcome predictor (HR 1.42, CI 1.081-1.866, p = 0.012). Increased circulating APN level was associated with higher mortality and may be an additive prognostic marker in DCM with advanced HF. Combination of serum (APN, BNP, TNF-α) and echocardiographic (AGS) markers may increase the HF predicting power for the nonischemic DCM patients.

Profiling nitric oxide metabolites in patients with idiopathic pulmonary arterial hypertension

Intact nitric oxide (NO) signalling is critical to maintaining appropriate pulmonary vascular tone. NO bioavailability is reduced in patients with pulmonary arterial hypertension. This study aimed to examine the impact of NO plasma metabolites (NOx) relative to haemodynamic dysfunction and mortality in patients with idiopathic pulmonary arterial hypertension (IPAH).

A total of 104 consecutive adult IPAH patients who had undergone genetic counselling when first diagnosed were enrolled in this prospective study.

The median concentration of NOx (μmol·L−1) was significantly lower in IPAH patients compared with healthy subjects, and was decreased further in 19 carriers of the bone morphogenetic protein-receptor type-2 (BMPR2) mutation compared to non-carriers. Reduced concentrations of NOx were correlated with mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR) and cardiac output. Compared with higher baseline NOx concentrations, patients with a NOx concentration of ≤10 μmol·L−1 had a markedly worse survival. After adjustment for clinical features, a BMPR2 mutation and haemodynamics, a lower NOx level remained an increased risk of mortality.

Patients with IPAH had lower levels of plasma NOx, which correlated inversely with mPAP, PVR and survival. Plasma NOx may be an important biomarker and prognostic indicator, suggesting that reduced NO synthesis contributes to the pathogenesis of IPAH.

Longitudinal associations between adiponectin and cardiac structure differ by hypertensive status: Coronary Artery Risk Development in Young Adults

OBJECTIVE

We studied the longitudinal association between adiponectin and cardiac structure and function 10 years later stratified by hypertension status.

METHODS

Multicenter longitudinal study of black and white men and women that began in 1985-1986, when participants were 18-30 years old. Adiponectin was measured at year 15(2000-2001). Echocardiograms were completed at year 25(2010-2011). Participants were stratified by the presence of hypertension. Risk factor-adjusted echocardiographic variables were compared across adiponectin quintiles. Linear and quadratic regression models were also derived for risk factor-adjusted echocardiographic variables.

RESULTS

Relative to the lowest quintile of adiponectin, participants from the highest quintile had a 6% lower LV mass index (LVMi) among normotensives, and an 8% higher LVMi among hypertensives. Among normotensive participants, regression analysis demonstrated a linear inverse relationship between adiponectin and LV mass, LVMi, posterior wall thickness (PWT) and ventricular septal thickness (VST) (all p≤0.05). Among hypertensive participants, regression analysis demonstrated a U-shaped relationship between adiponectin and LV mass, LVMi, PWT and VST (p≤0.005 for all quadratic terms).

CONCLUSIONS

Among normotensive participants, higher adiponectin may be a useful marker of less adverse future cardiac structure. Further study is required to see if adiponectin receptor agonists may provide a benefit among these individuals. Among hypertensive participants, further study is required to assess the prognostic and therapeutic use of adiponectin.

Hypoadiponectinemia, cardiometabolic comorbidities and left ventricular hypertrophy

This study was designed to evaluate the prevalence of cardiometabolic comorbidities and the changes in left ventricular geometry and function in 135 subjects subgrouped according to low or normal total adiponectin plasma (ADPN) levels. Left ventricular (LV) internal diameter/height, total LV mass (LVM) and LVM index (LVMI), relative wall thickness (RWT), LV ejection fraction by echocardiography and diastolic parameters by pulsed-wave Doppler were calculated. Body mass index (BMI) (p < 0.0001), waist-to-hip ratio (p < 0.03), triglycerides (p < 0,001), prevalence of obesity (p < 0.005), visceral obesity (p < 0.003), left ventricular hypertrophy (LVH) (p < 0.001), metabolic syndrome (p < 0.0003) and coronary artery disease (CAD) (p < 0.003) were significantly increased and high-density lipoprotein-cholesterol (p < 0.001) was significantly reduced in hypo-ADPN than normal-ADPN subjects. LVM, LVMI, interventricular septum thickness and RWT were significantly (p < 0.0001) higher and left ventricular ejection fraction was significantly (p < 0.0002) lower in hypo-ADPN than normal-ADPN patients. LVMI correlated directly with BMI (p < 0.001), mean blood pressure (p < 0.001), metabolic syndrome (MetS) (p < 0.001) and inversely with ADPN (p < 0.0001). The prevalence of LVH (p < 0.001) and CAD (p < 0.01) was higher in subjects with normal-ADPN and MetS, while the presence of MetS did not change this finding in hypo ADPN group. Both models of regression analysis indicated that ADPN and BMI resulted independently associated with LVMI. In conclusion, our data seem to indicate that hypoadiponectinemia might be associated with an increased prevalence both of clinical comorbidities and increased LVMI. In this subset of subjects, ADPN and BMI, more than MetS, are able to explain cardiac damage. Accordingly, ADPN might become a new target in the management of cardiometabolic risk.

Body mass index-modified relationship of chronic mental stress with resting blood pressure during 5 years in Japanese middle-aged male workers

BACKGROUND

Chronic mental stress has been reported to be directly or inversely proportional to blood pressure (BP). To explain this inconsistent relationship, we assumed effect-modification by body mass index (BMI).

METHODS AND RESULTS

We examined 1,673 Japanese male local government employees who were not taking antihypertensive drugs or had no history of cardiovascular disease. BP and BMI were recorded at yearly health checkups. Exposure to mental stress, smoking, drinking, exercising, and salty taste were checked by questionnaire in 1997 and 2002. The main effect and interaction of stress and BMI on the averages and changes of resting systolic and diastolic BPs over the 5 years were assessed by a general linear model by adjusting for confounders. Obesity (BMI ≥25kg/m(2)) was significantly related with higher average systolic and diastolic BPs (P<0.001, P<0.001, respectively), whereas mental stress was not, showing a significantly different relationship dependent on BMI (P for interaction =0.002, 0.004): a significant and directly proportional association with systolic and diastolic BPs (P=0.001, 0.001) in the obese, but borderline significant and inversely proportional association (P=0.07, 0.08) in the lean. Only BMI was significantly related to the degree of BP change.

CONCLUSIONS

Whereas BMI was proportionally associated with BP, BMI was a modifier which, depending on its level, inverted the direction of the association between chronic mental stress and resting BP.

Relations of plasma total and high-molecular-weight adiponectin to new-onset heart failure in adults ≥65 years of age (from the Cardiovascular Health study)

Adiponectin exhibits cardioprotective properties in experimental studies, but elevated levels have been linked to increased mortality in older adults and patients with chronic heart failure (HF). The adipokine's association with new-onset HF remains less well defined. The aim of this study was to investigate the associations of total and high-molecular weight (HMW) adiponectin with incident HF (n = 780) and, in a subset, echocardiographic parameters in a community-based cohort of adults aged ≥65 years. Total and HMW adiponectin were measured in 3,228 subjects without prevalent HF, atrial fibrillation or CVD. The relations of total and HMW adiponectin with HF were nonlinear, with significant associations observed only for concentrations greater than the median (12.4 and 6.2 mg/L, respectively). After adjustment for potential confounders, the hazard ratios per SD increment in total adiponectin were 0.93 (95% confidence interval 0.72 to 1.21) for concentrations less than the median and 1.25 (95% confidence interval 1.14 to 1.38) higher than the median. There was a suggestion of effect modification by body mass index, whereby the association appeared strongest in participants with lower body mass indexes. Consistent with the HF findings, higher adiponectin tended to be associated with left ventricular systolic dysfunction and left atrial enlargement. Results were similar for HMW adiponectin. In conclusion, total and HMW adiponectin showed comparable relations with incident HF in this older cohort, with a threshold effect of increasing risk occurring at their median concentrations. High levels of adiponectin may mark or mediate age-related processes that lead to HF in older adults.

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.

Plasma adiponectin: a contributing factor for cardiac changes in visceral obesity-associated hypertension

This study has been designed to evaluate the impact of adiponectin levels on left ventricular geometry and function in visceral obesity-associated hypertension. 94 consecutive subjects, 53 of them were hypertensives and 41 normotensives with age ≤ 65 years, subgrouped according to the presence or absence of visceral obesity, were studied. Total adiponectin levels were measured by a validated competitive radioimmunoassay. Left ventricular telediastolic internal diameter, interventricular septum, posterior wall thickness, total left ventricular mass (LVM) and normalized for height to the 2.7 power (LVM/h(2.7)), relative wall thickness, left ventricular ejection fraction by echocardiography and isovolumic relaxation time, E/A ratio and deceleration time of E velocity, by pulsed-wave Doppler, were calculated. Plasma adiponectin levels were significantly lower in visceral obesity-associated hypertensives than lean hypertensives (p < 0.001) and in lean normotensives (p < 0.001). LVM and LVM/h(2.7) were significantly (p < 0.05) higher in both hypertensive groups, and in visceral obesity-associated normotensives in comparison with lean normotensives. Adiponectin levels correlated inversely with LVM/h(2.7) but only in normotensives (adjusted R squared 0.77, p < 0.0001) and hypertensives (0.67, p < 0.0001) subjects with visceral obesity. Multiple regression analysis indicated that adiponectin levels remain significantly associated (p < 0.001) to LVM/h(2.7) also when adjusted for age, gender, body mass index, waist to hip ratio and mean blood pressure. Our data suggest an important role of adiponectin in increased LVM/h(2.7) in visceral obesity-associated normotensive and hypertensive subjects. In this last group, adiponectin, more than blood pressure, may be able to explain the development of cardiac damage.

The relationship between adiponectin and left ventricular mass index varies with the risk of left ventricular hypertrophy

BACKGROUND

Adiponectin directly protects against cardiac remodeling. Despite this beneficial effect, most epidemiological studies have reported a negative relationship between adiponectin level and left ventricular mass index (LVMI). However, a positive relationship has also been reported in subjects at high risk of left ventricular hypertrophy (LVH). Based on these conflicting results, we hypothesized that the relationship between serum adiponectin level and LVMI varies with the risk of LVH.

METHODS

A community-based, cross-sectional study was performed on 1414 subjects. LVMI was measured by echocardiography. Log-transformed adiponectin levels (Log-ADPN) were used for the analysis.

RESULTS

Serum adiponectin level had a biphasic distribution (an increase after a decrease) with increasing LVMI. Although Log-ADPN did not correlate with LVMI, Log-ADPN was modestly associated with LVMI in the multivariate analysis (β = 0.079, p = 0.001). The relationship between adiponectin level and LVMI was bidirectional according to the risk of LVH. In normotensive subjects younger than 50 years, Log-ADPN negatively correlated with LVMI (r = -0.204, p = 0.005); however, Log-ADPN positively correlated with LVMI in ≥50-year-old obese subjects with high arterial stiffness (r = 0.189, p = 0.030). The correlation coefficient between Log-ADPN and LVMI gradually changed from negative to positive with increasing risk factors for LVH. The risk of LVH significantly interacted with the relationship between Log-ADPN and LVMI. In the multivariate analysis, Log-ADPN was associated with LVMI in the subjects at risk of LVH; however, Log-ADPN was either not associated or negatively associated with LVMI in subjects at low risk of LVH.

CONCLUSION

Adiponectin level and LVMI are negatively associated in subjects at low risk of LVH and are positively associated in subjects at high risk of LVH. Therefore, the relationship between adiponectin and LVMI varies with the risk of LVH.

Decreased plasma adiponectin is associated with impaired left ventricular longitudinal systolic function in hypertensive patients: a two-dimensional speckle tracking study

The influence of plasma adiponectin levels on myocardial contractile function has not been fully examined. We aimed to investigate the relationship between three-directional systolic function and plasma adiponectin levels in asymptomatic hypertensive patients using two- dimensional speckle-tracking echocardiography. The study population consisted of 78 patients with hypertension and 40 healthy controls. Longitudinal strain was significantly reduced in all patients, including those without LV hypertrophy (p=0.009). In multiple-regression analysis, plasma adiponectin levels (β=-0.273, p=0.008) and LV mass index (β=0.458, p<0.001) independently correlated with LV longitudinal strain. Decreased plasma adiponectin concentrations were associated with the progression of LV hypertrophy with impaired LV longitudinal systolic function.

Adipose tissue biology and cardiomyopathy: translational implications

It is epidemiologically established that obesity is frequently associated with the metabolic syndrome and poses an increased risk for the development of type 2 diabetes mellitus and cardiovascular disease. The molecular links that connect the phenomenon of obesity, per se, with insulin resistance and cardiovascular disease are still not fully elucidated. It is increasingly apparent that fully functional adipose tissue can be cardioprotective by reducing lipotoxic effects in other peripheral tissues and by maintaining a healthy balance of critical adipokines, thereby allowing the heart to maintain its full metabolic flexibility. The present review highlights both basic and clinical findings that emphasize the complex interplay of adipose tissue physiology and adipokine-mediated effects on the heart exerted by either direct effects on cardiac myocytes or indirect actions via central mechanisms through sympathetic outflow to the heart.

Angiotensin II reduces cardiac AdipoR1 expression through AT1 receptor/ROS/ERK1/2/c-Myc pathway

Adiponectin, an abundant adipose tissue-derived protein, exerts protective effect against cardiovascular disease. Adiponectin receptors (AdipoR1 and AdipoR2) mediate the beneficial effects of adiponectin on the cardiovascular system. However, the alteration of AdipoRs in cardiac remodeling is not fully elucidated. Here, we investigated the effect of angiotensin II (AngII) on cardiac AdipoRs expression and explored the possible molecular mechanism. AngII infusion into rats induced cardiac hypertrophy, reduced AdipoR1 but not AdipoR2 expression, and attenuated the phosphorylations of adenosine monophosphate-activated protein kinase and acetyl coenzyme A carboxylase, and those effects were all reversed by losartan, an AngII type 1 (AT1) receptor blocker. AngII reduced expression of AdipoR1 mRNA and protein in cultured neonatal rat cardiomyocytes, which was abolished by losartan, but not by PD123319, an AT2 receptor antagonist. The antioxidants including reactive oxygen species (ROS) scavenger NAC, NADPH oxidase inhibitor apocynin, Nox2 inhibitor peptide gp91 ds-tat, and mitochondrial electron transport chain complex I inhibitor rotenone attenuated AngII-induced production of ROS and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2. AngII-reduced AdipoR1 expression was reversed by pretreatment with NAC, apocynin, gp91 ds-tat, rotenone, and an ERK1/2 inhibitor PD98059. Chromatin immunoprecipitation assay demonstrated that AngII provoked the recruitment of c-Myc onto the promoter region of AdipoR1, which was attenuated by PD98059. Moreover, AngII-induced DNA binding activity of c-Myc was inhibited by losartan, NAC, apocynin, gp91 ds-tat, rotenone, and PD98059. c-Myc small interfering RNA abolished the inhibitory effect of AngII on AdipoR1 expression. Our results suggest that AngII inhibits cardiac AdipoR1 expression in vivo and in vitro and AT1 receptor/ROS/ERK1/2/c-Myc pathway is required for the downregulation of AdipoR1 induced by AngII.

Adiponectin: anti-inflammatory and cardioprotective effects

Adipose tissue is an endocrine organ that plays an essential role in regulating several metabolic functions through the secretion of biological mediators called "adipokines". Dysregulation of adipokines plays a crucial role in obesity-related diseases. Adiponectin (APN) is the most abundant adipokine accounting for the 0.01% of total serum protein, and is involved in a wide variety of physiological processes including energy metabolism, inflammation, and vascular physiology. APN plasma levels are reduced in individuals with obesity, type 2 diabetes and coronary artery disease, all traits with low-grade chronic inflammation. It is has been suggested that the absence of APN anti-inflammatory effects may be a contributing factor to this inflammation. APN inhibits the expression of tumor necrosis factor-α-induced endothelial adhesion molecules, macrophage-to-foam cell transformation, tumor necrosis factor-α expression in macrophages and adipose tissue, and smooth muscle cell proliferation. It also has anti-apoptotic and anti-oxidant effects, which play a role in its cardioprotective action. This review will focus on APN as an anti-inflammatory, anti-atherogenic and cardioprotective plasma protein.

Adiponectin and cardiovascular health: an update

The global epidemic of obesity is accompanied by an increased prevalence of cardiovascular disease (CVD), in particular stroke and heart attack. Dysfunctional adipose tissue links obesity to CVD by secreting a multitude of bioactive lipids and pro-inflammatory factors (adipokines) with detrimental effects on the cardiovascular system. Adiponectin is one of the few adipokines that possesses multiple salutary effects on insulin sensitivity and cardiovascular health. Clinical investigations have identified adiponectin deficiency (hypoadiponectinaemia) as an independent risk factor for CVD. In animals, elevation of plasma adiponectin by either pharmacological or genetic approaches alleviates obesity-induced endothelial dysfunction and hypertension, and also prevents atherosclerosis, myocardial infarction and diabetic cardiomyopathy. Furthermore, many therapeutic benefits of the peroxisome-proliferator activated receptor gamma agonists, the thiazolidinediones, are mediated by induction of adiponectin. Adiponectin protects cardiovascular health through its vasodilator, anti-apoptotic, anti-inflammatory and anti-oxidative activities in both cardiac and vascular cells. This review summarizes recent findings in the understanding of the physiological role and clinical relevance of adiponectin in cardiovascular health, and in the identification of the receptor and postreceptor signalling events that mediate the cardiovascular actions of adiponectin. It also discusses adiponectin-targeted drug discovery strategies for treating obesity, diabetes and CVD.

LINKED ARTICLES

This article is part of a themed section on Fat and Vascular Responsiveness. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2012.165.issue-3.

Association of adiponectin with left ventricular mass in blacks: the Jackson Heart Study

BACKGROUND

Blacks have a higher prevalence of left ventricular hypertrophy than whites. Several population-based studies have reported an inverse association between adiponectin and left ventricular mass (LVM); however, the relationship between adiponectin levels and LVM has yet to be defined in blacks. The Jackson Heart Study cohort provides an opportunity to test the hypothesis that the inverse association between adiponectin and LVM may be modified by risk factors common among blacks.

METHODS AND RESULTS

The study population included 2649 black Jackson Heart Study participants (mean age 51±12 years, 63% women, 51% obese, 54% with hypertension, and 16% with diabetes). Multiple linear and spline regression was used to assess the association, with adjustment for demographic, clinical, and behavioral covariates. Among all the participants, there was a statistically significant but modest inverse association between adiponectin and LVM index. Hypertension and insulin resistance emerged as statistically significant effect modifiers of this relationship. The inverse association present among the normotensive participants was explained by obesity measures such as the body mass index. Among participants with both hypertension and insulin resistance, there was a significant direct association between adiponectin and the LVM index after multivariable adjustment (β=1.55, P=0.04, per 1-SD increment in the adiponectin log value).

CONCLUSIONS

The association between serum adiponectin and LVM among blacks in the Jackson Heart Study cohort was dependent on hypertension and insulin resistance status. Normotensive blacks exhibited an inverse adiponectin-LVM association, whereas participants with hypertension and insulin resistance had a direct association.

Waist circumference modifies the relationship between the adipose tissue cytokines leptin and adiponectin and all-cause and cardiovascular mortality in haemodialysis patients

BACKGROUND

the relationships between the adipose tissue cytokines leptin and adiponectin (ADPN) and clinical outcomes have not been well studied in haemodialysis (HD) patients and remain highly controversial. As central obesity is an important modifier of the effect of various risk factors for clinical outcomes, we tested the hypothesis that waist circumference (WC) modifies the link between these cytokines and both overall and cardiovascular death in HD patients.

METHODS

a total of 537 HD patients participated in a prospective cohort study.

RESULTS

leptin and ADPN were inversely related to each other and robustly associated with WC (P < 0.001). During follow-up (average 29 months, range 1-47 months) 182 patients died, including 115 from cardiovascular causes. In analyses adjusting for potential confounders, there were strong interactions between leptin and WC in relationship to both all-cause (P < 0.001) and cardiovascular death (P = 0.002). Accordingly, a fixed excess of leptin signalled a gradually increasing risk for all-cause and cardiovascular mortality in patients with a large WC but an opposite effect in those with a relatively small WC. An interaction between ADPN and WC for all-cause (P = 0.01) and cardiovascular mortality (P = 0.01) emerged only in models excluding the leptin-WC interaction, suggesting that these adipokines share a common pathway leading to adverse clinical events in HD patients.

CONCLUSIONS

the predictive value of leptin and ADPN for all-cause and cardiovascular death in HD patients appears to be critically dependent on WC. These findings support the hypothesis that disturbances in adipokine levels are involved in adverse clinical outcomes in HD patients with abdominal obesity.

Adiponectin provides cardiovascular protection in metabolic syndrome

Adipose tissue plays a central role in the pathogenesis of metabolic syndrome. Adiponectin (APN) is a bioactive adipocytokine secreted from adipocytes. Low plasma APN levels (hypoadiponectinemia) are observed among obese individuals and in those with related disorders such as diabetes, hypertension, and dyslipidemia. APN ameliorates such disorders. Hypoadiponectinemia is also associated with major cardiovascular diseases including atherosclerosis and cardiac hypertrophy. Accumulating evidence indicates that APN directly interacts with cardiovascular tissue and prevents cardiovascular pathology. Increasing plasma APN or enhancing APN signal transduction may be an ideal strategy to prevent and treat the cardiovascular diseases associated with metabolic syndrome. However, further studies are required to uncover the precise biological actions of APN.

Plasma adiponectin concentration and left ventricular hypertrophy in kidney transplant patients

BACKGROUND

Low plasma adiponectin concentration is associated with more frequent occurrence of left ventricular hypertrophy (LVH) and more exaggerated intima-media thickness of common carotid artery (IMT). IMT is an early surrogate marker of atherosclerosis. This study aimed to assess the relationship between plasma adiponectin concentration and left ventricular mass index (LVMI) and IMT in kidney transplant patients (KTP).

METHODS

In 88 adult KTP, plasma adiponectin concentration, LVMI, and IMT were estimated. LVH was defined as LVMI >110 or >125 g/m(2) for females and males, respectively. Data presented are means and 95% CI.

RESULTS

Plasma adiponectin concentration was similar in KTP with (n = 42) or without LVH (n = 46) (13.5 [11.4-15.6] vs. 13.1 [11.6-14.6] μg/mL, respectively), as well as in KTP subgroups divided according to the IMT value tertiles (p = 0.42) (11.7 [10.0-13.3], 14.2 [11.7-16.6], and 14.0 [11.7-16.4] μg/mL in the lowest, middle, and highest tertiles, respectively). Plasma glucose concentrations were similar in KTPs with LVH or without LVH. No significant correlation was found between plasma adiponectin concentration and both LVMI (R = -0.02; p = 0.87) and IMT (R = 0.09; p = 0.38), respectively.

CONCLUSION

Results of this cross-sectional study do not confirm the roles of low adiponectin and high glucose in the pathogenesis of LVH and atherosclerosis in KTP.

Correlation relationship assessment between left ventricular hypertrophy voltage criteria and body mass index in 41,806 Swiss conscripts

INTRODUCTION

Electrocardiographic criteria for left ventricular hypertrophy (LVH) have been limited by low sensitivity at acceptable levels of specificity. A number of studies have demonstrated that body mass index (BMI) is associated with decreased sensitivity of ECG LVH classification in hypertensive patients. The objective of this study is to investigate the correlation relationship between LVH voltage criteria and BMI in Swiss conscripts.

METHODS

A database of 41,806 young Swiss people, who underwent compulsory conscription for the Swiss Army, was compiled. Along with other medical data, an ECG was taken. Statistical analyses, such as linear regression and calculation of correlation coefficient, were carried out between LVH voltage criteria and BMI.

RESULTS

The mean age in the studied population was 19.2 +/- 1.1 years with a median age of 19 years (range from 17 to 38 years). We found an overweight prevalence of 25.1%. The results showed that body habitus had significant association with Sokolow-Lyon voltages. A mean decrease of 13%, 5%, 19%, 14%, and 12% for the five studied Sokolow-Lyon indexes were found between normal range subjects (18.5 < or = BMI < 25) and obese subjects (25< or = BMI).

CONCLUSIONS

Our study confirms the hypothesis that people with higher BMI, a growing section of the population, have lower ECG amplitudes. Therefore, the Sokolow-Lyon voltage criteria may underestimate the presence of LVH for subjects with higher BMI, which is not the case for the Cornell voltage. Our analysis suggests that computerized electrocardiography for the diagnosis of left ventricular hypertrophy based on Sokolow-Lyon voltages should incorporate the BMI factor.

Non-alcoholic fatty liver disease is associated with left ventricular diastolic dysfunction in essential hypertension

BACKGROUND AND AIM

Insulin resistance is recognized as the pathophysiological hallmark of non-alcoholic fatty liver disease (NAFLD). A relation between insulin sensitivity and left ventricular morphology and function has been reported in essential hypertension, where a high prevalence of NAFLD has been recently found. We investigated the inter-relationship between left ventricular morphology/function, metabolic parameters and NAFLD in 86 never-treated essential hypertensive patients subdivided in two subgroups according to the presence (n = 48) or absence (n = 38) of NAFLD at ultrasonography.

METHODS AND RESULTS

The two groups were similar as to sex, age and blood pressure levels. No patient had diabetes mellitus, obesity, hyperlipidemia, or other risk factors for liver disease. Body mass index, waist circumference, triglycerides, glucose, insulin, homeostasis model of assessment index for insulin resistance (HOMA-IR), aspartate aminotransferase and alanine aminotransferase were higher and adiponectin levels were lower in patients with NAFLD than in patients without NAFLD, and were associated with NAFLD at univariate analysis. Patients with NAFLD had similar prevalence of left ventricular hypertrophy compared to patients without NAFLD, but a higher prevalence of diastolic dysfunction (62.5 vs 21.1%, P < 0.001), as defined by E/A ratio <1 and E-wave deceleration time >220 ms. Diastolic dysfunction (P = 0.040) and HOMA-IR (P = 0.012) remained independently associated with NAFLD at backward multivariate analysis.

CONCLUSIONS

Non-alcoholic fatty liver disease was associated with insulin resistance and abnormalities of left ventricular diastolic function in a cohort of patients with essential hypertension, suggesting a concomitant increase of metabolic and cardiac risk in this condition.

Chronic glucagon-like peptide-1 infusion sustains left ventricular systolic function and prolongs survival in the spontaneously hypertensive, heart failure-prone rat

BACKGROUND

Glucagon-like peptide-1 (GLP-1) treatment leads to short-term improvements in myocardial function in ischemic and nonischemic cardiomyopathy. It is unknown whether GLP-1 improves survival when administered over a longer time period. Spontaneously hypertensive, heart failure-prone (SHHF) rats progress to advanced heart failure and death over a 15-month period. The authors sought to determine whether a continuous infusion of GLP-1 would reduce mortality in this model.

METHODS AND RESULTS

At 9 months of age, 50 SHHF rats were randomized to receive a 3-month, continuous infusion of either GLP-1 or saline. Metabolic parameters were measured and cardiac ultrasounds performed at study initiation and completion of treatment. Surviving rats were euthanized at 12 months. Hearts were perfused in an isolated, isovolumic heart preparation, and Tunel staining of myocardial samples was performed. Baseline metabolic and cardiac functional parameters were comparable. GLP-1-treated SHHF rats had greater survival (72% versus 44%, P=0.008) at 12 months of age. In addition, GLP-1 treatment led to higher plasma insulin, lower plasma triglycerides, and preserved left ventricular (LV) function. GLP-1-treated rats demonstrated decreased myocyte apoptosis by Tunel staining as well as reduced caspase-3 activation. No increase in p-BAD expression was seen. In isolated hearts, the LV systolic pressure and LV-developed pressure were greater in the GLP-1 group. Myocardial glucose uptake was also increased in GLP-1-treated SHHF rats.

CONCLUSIONS

Chronic GLP-1 treatment prolongs survival in obese SHHF rats. This is associated with preserved LV function and LV mass index, increased myocardial glucose uptake, and reduced myocyte apoptosis.

Impact of adiponectin on left ventricular mass index in non-complicated obese subjects

To evaluate the relationship between the adiponectin levels and left ventricular mass index (LVMI) in uncomplicated obese subjects. Fifty-nine subjects were assigned to the obese (BMI> or =30 kg/m(2)) and 58 to the lean (BMI<30 kg/m (2) ) group. Plasma glucose, insulin, serum total cholesterol and high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, triglycerides and adiponectin were measured. Insulin resistance was determined by the Homeostasis Assessment Model (HOMA-IR). The left ventricular functions of all subjects were determined by 2D and pulse wave Doppler echocardiography. LVMI was calculated as left ventricular mass (LVM) normalized for height in m (2.7) . The obese group displayed significantly higher LVMI and late mitral inflow velocity. Thirty-three obese subjects met the criteria for left ventricular hypertrophy (LVH) and had lower serum adiponectin levels compared with obese subjects without LVH and lean subjects (p<0.05). Adiponectin was negatively correlated with LVMI (R: -0.277, p: 0.002). Furthermore, during the partial correlation analysis where HOMA-IR was controlled, the negative correlation between adiponectin and LVMI progressed (r: -0.283, p: 0.002). The linear regression analysis showed an independent relationship between LVMI and adiponectin. (beta: -0.214, p: 0.01) Obesity is associated with LVH. This study showed direct influence of adiponectin on LVMI.

Adiponectin and left ventricular structure and function in healthy adults

CONTEXT

Adiponectin inhibits protein synthesis in cardiac myocytes, thereby opposing the effect of cardiac workload and trophic factors (in particular, insulin) on left ventricular (LV) mass and wall thickness (WT).

OBJECTIVE

We tested whether adiponectin and its isoforms are related to LV mass, WT, and function independently of metabolic factors.

DESIGN

This was a cross-sectional study.

SUBJECTS

The study included 77 healthy volunteers (42 men) aged 30-59 yr with normal LV structure and function.

MAIN OUTCOME MEASURES

Insulin response and insulin sensitivity were assessed by oral glucose tolerance test and euglycemic hyperinsulinemic clamp. LV mass, WT, stroke work, chamber function, and myocardial longitudinal function were evaluated by standard Doppler echocardiography and tissue Doppler imaging. Total and molecular isoforms of adiponectin were measured in plasma.

RESULTS

By multivariate analysis, independent factors affecting LV mass were sex, body mass index, stroke work, and current smoking (R(2) = 0.66). Independent correlates of LV WT were age, stroke work, and plasma adiponectin (standardized r = 0.28, 0.41, and -0.26, P at least < 0.005, R(2) = 0.48). LV longitudinal late diastolic velocity was independently related to age, body mass index, and adiponectin (standardized r = 0.20, 0.26, -0.33, P at least < 0.05, R(2) = 0.30). High-molecular-weight adiponectin (47% of total), but not lower molecular-weight isoforms, insulin sensitivity, or other metabolic factors, was inversely and independently related to WT (standardized r = -0.27, P < 0.01) and myocardial longitudinal late diastolic velocity (standardized r = -0.28, P < 0.05).

CONCLUSION

In healthy subjects, circulating total and high-molecular-weight adiponectin are related to LV WT and diastolic function, independently of age and metabolic factors.

Potential of adiponectin as a cardioprotective agent

In this review, we focus on the role of adiponectin as a cardioprotective agent in several pathological heart conditions. Obesity is closely associated with Type 2 diabetes, hypertension and heart disease. Adiponectin is an adipose tissue-derived hormone whose concentration is downregulated in subjects with obesity-related diseases. Hypoadiponectinemia has been identified as an independent risk factor for Type 2 diabetes, coronary artery disease, acute coronary syndrome and hypertension. More recent experimental findings have shown that adiponectin directly affects signaling in cardiac myocytes and has beneficial effects on several pathological heart conditions, including cardiac hypertrophy and myocardial infarction. The favorable effects of adiponectin are associated with attenuated inflammatory response, decreased myocyte death, decreased hypertrophic response, maintained ischemia-induced angiogenesis and reduced interstitial fibrosis. Therefore, adiponectin could represent a molecular target for treating obesity-linked cardiac diseases.

Pathophysiologic mechanisms of obesity and related metabolic disorders: an epidemiologic study using questionnaire and serologic biomarkers

BACKGROUND

It is still unclear whether individuals with the same degree of obesity but different weight histories since young adulthood have different insulin concentration, prevalence of metabolic syndrome components and their clustering.

METHODS

A cross-sectional study was conducted on 3,399 (for weight difference analysis) and 1,879 (for weight fluctuation analysis) Japanese men aged 40-59 years. Weight difference was calculated by subtracting the recalled weight at about 25 years old from the current weight. The root mean square error around the slope of weight on age (weight - RMSE) was calculated by a simple linear regression model, in which the subject's actual weights at ages 20, 25, 30, 40 years and 5 years prior to the study, as well as current weight, were dependent variables against the subject's age as the independent variable. Each metabolic syndrome component was defined as follows: serum triglycerides ≥150 mg/dL; HDL-cholesterol <40 mg/dL; fasting glucose ≥110 mg/dL; and blood pressure ≥140/90 mm Hg.

RESULTS

Those who gained <10%, <20%, or 20% or more in weight had a significantly higher than unity odds ratio of having two or more metabolic syndrome components in relation to those whose weight remained stable: 1.28 (95% confidence interval: 0.95-1.73), 2.49 (1.91-3.24), and 5.30 (3.97-7.07), respectively. Weight-RMSE was significantly and positively associated with fasting insulin concentration independent of current weight, weight-slope or other lifestyle-related factors.

CONCLUSIONS

Metabolic syndrome components would likely tend to cluster more in individuals with large weight gain on a physiologic basis characterized by high fasting insulin concentration. Furthermore, weight fluctuation was suggested to increase the risk of fasting hyperinsulinemia.