Plasma adiponectin levels are associated with coronary lesion complexity in men with coronary artery disease

Atheroprotective Roles of Adiponectin via CCL2 Inhibition

Aim: Adiponectin (APN) exhibits different atheroprotective effects, and we have previously reported that APN function is modulated by its binding proteins, E-selectin ligand 1, Mac-2 binding protein, and cystatin C. In the present study, we aimed to identify a novel atheroprotective mechanism of APN via C–C motif chemokine 2 (CCL2).

Methods: We conducted iMAP ^® -intravascular ultrasound (IVUS) in 111 Japanese male patients with stable angina. The plaque characteristics were determined where “plaque burden” [(EEM CSA − lumen CSA)/(EEM CSA)×100 (%)] ＞50%, and their correlation with serum CCL2 and APN levels was analyzed. Using western blot analysis, the effects of APN on the biological effects of CCL2 were examined in their mutual binding by co-immunoprecipitation assay, the monocyte migration, and the phosphorylation of MAP kinases.

Results: In a clinical study, we found that the percentage of plaque in the culprit lesion was correlated positively with serum CCL2 and negatively with serum APN levels, with significance. We identified CCL2 as a novel APN-binding serum protein using immunoprecipitation and western blot analysis. CCL2-induced phosphorylation of MAP kinases and monocyte migration was significantly attenuated by APN in vitro .

Conclusion: The opposite association of APN and CCL2 on the percentage of coronary plaque might be caused by their direct interaction and competitive functions on monocyte migration.

Low Plasma Adiponectin Levels Are Associated With Vulnerable Plaque Features in Patients With Acute Coronary Syndrome: An Optical Coherence Tomography Study

BACKGROUND

Vulnerable plaques are the primary cause of acute coronary syndrome (ACS). The association between in-vivo plaque vulnerability and adiponectin levels in ACS still remains to be determined.

OBJECTIVE

The purpose of this study was to investigate the correlation between adiponectin levels and vulnerable plaque features in ACS patients.

METHODS

We enrolled 107 ACS patients admitted to our institution; 83 with Non-ST elevation ACS (NSTE-ACS) and 24 with ST-elevation myocardial infarction (STEMI). Adiponectin levels were measured in these patients. Coronary angiography and subsequent optical coherence tomography (OCT) analysis of culprit lesions were performed.

RESULTS

Adiponectin level was lower in patients with complex angiographic lesions, compared to those with non-complex lesions (7.13 ± 3.04 vs. 8.94 ± 2.84 μg/ml, P = 0.002). Adiponectin level was lower in patients with plaque rupture (PR), micro-thrombi, and thin cap fibroatheroma (TCFA), compared to those with non-vulnerable features (7.19 ± 2.95 vs 8.79 ± 3.02 μg/ml, P = 0.007 & 7.29 ± 2.97 vs 8.44 ± 3.09 μg/ml, P = 0.04 and 4.76 ± 0.65 vs 9.74 ± 2.35 μg/ml, P < 0.001 μg/ml respectively). There was a significant negative correlation between adiponectin levels and lipid rich plaque extent and maximum lipid arc (r = -0.05, P < 0.001 & r = -0.03, P = 0.03, respectively). However, a significant positive correlation was observed between adiponectin levels and fibrous cap thickness (r = 0.95, P < 0.001).

CONCLUSION

Low adiponectin levels were associated with complex angiographic lesions and vulnerable plaque features in ACS patients, where there was a significant correlation between it and PR, TCFA, and lipid rich plaque.

Adiponectin and Leptin Adipocytokines in Metabolic Syndrome: What Is Its Importance?

The global obesity epidemic has motivated a large number of investigations related to adipose tissue. Within the advances in this area, a variety of factors secreted by adipose tissue and with regulatory activity on caloric intake, energy expenditure, reproduction, locomotor activity, glycidic and lipid metabolism, immune response, and bone physiology have been described. Among these adipocyte hormones, collectively called “adipokines” or “adipocytokines,” leptin (LEP) and adiponectin are addressed in this review. The regulation of adipocytokines is altered in diseases such as obesity, atherosclerosis, type 2 diabetes mellitus, and metabolic syndrome (MS) due to the increase in the mass of white adipose tissue. LEP and adiponectin have a broad spectrum of functions in regulating metabolism and are an important link between obesity and MS. Because these adipocytokines have opposite effects on subclinical inflammation and insulin resistance, it has been suggested that the combined use of these 2 adipocytokines may work as a better biomarker in the diagnosis of MS than using them individually. In this review, we address the characteristics and main functions of adipocytokines derived from adipose tissue such as adiponectin and LEP, which in the Colombian context could give good guidance for the management of MS, especially in populations of children and adolescents.

Adiponectin, Obesity, and Cancer: Clash of the Bigwigs in Health and Disease

Adiponectin is one of the most important adipocytokines secreted by adipocytes and is called a “guardian angel adipocytokine” owing to its unique biological functions. Adiponectin inversely correlates with body fat mass and visceral adiposity. Identified independently by four different research groups, adiponectin has multiple names; Acrp30, apM1, GBP28, and AdipoQ. Adiponectin mediates its biological functions via three known receptors, AdipoR1, AdipoR2, and T-cadherin, which are distributed throughout the body. Biological functions of adiponectin are multifold ranging from anti-diabetic, anti-atherogenic, anti-inflammatory to anti-cancer. Lower adiponectin levels have been associated with metabolic syndrome, type 2 diabetes, insulin resistance, cardiovascular diseases, and hypertension. A plethora of experimental evidence supports the role of obesity and increased adiposity in multiple cancers including breast, liver, pancreatic, prostrate, ovarian, and colorectal cancers. Obesity mediates its effect on cancer progression via dysregulation of adipocytokines including increased production of oncogenic adipokine leptin along with decreased production of adiponectin. Multiple studies have shown the protective role of adiponectin in obesity-associated diseases and cancer. Adiponectin modulates multiple signaling pathways to exert its physiological and protective functions. Many studies over the years have shown the beneficial effect of adiponectin in cancer regression and put forth various innovative ways to increase adiponectin levels.

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.

Circulating levels of adiponectin and extent of coronary artery disease in patients undergoing elective coronary angiography

Adiponectin (APN), an adipose tissue-released adipokine with demonstrated anti-inflammatory and anti-atherogenic properties, is encoded by a gene whose polymorphisms are associated with presence of coronary artery disease (CAD). Serum APN levels are inversely related with presence and complexity of CAD. Within this context, we sought to compare levels of total APN and its high molecular weight form (HMW APN) according to clinical presentation and extent of CAD in patients undergoing elective cardiac catheterization. From March 2008 to June 2010, clinical data and blood samples for APN and HMW APN measurements were collected from 415 subjects undergoing cardiac catheterization at two tertiary centers. CAD extent was estimated by the number of coronary arteries with significant stenosis (≥70% obstruction in a major coronary artery) and by Duke Jeopardy Score (DJS). Serum APN levels were similar between groups with stable or unstable CAD (APN 9.20±5.88 vs 9.47±6.23 μg/mL, P=0.738, and HMW APN 5.31±3.72 vs 5.91±4.16 μg/mL, P=0.255), even after stratification by the number of arteries involved (single-vessel vs multivessel disease: APN 9.39±5.76 vs 9.26±6.27 μg/mL, P=0.871; HMW APN 5.29±3.79 vs 5.83±4.04 μg/mL, P=0.306) and DJS score (APN, P=0.718; HMW APN, P=0.276). We conclude that APN and HMW APN serum levels are similar across clinical presentations and different extents of CAD, despite being significantly lower in the presence of obstructive CAD.

Severe degenerative aortic stenosis with preserved ejection fraction does not change adipokines serum levels

BACKGROUND

The role of the adipokines in the pathogenesis of aortic stenosis (AS) is not well established. The aim was to evaluate the relationship between adipokines and clinical characteristics as well as echocardiographic indices and noninvasive markers of vascular remodeling in patients with severe AS with preserved ejection fraction (EF).

METHODS

Sixty-five patients (F/M: 38/27; age: 68.3 ± 9.0 years; body mass index [BMI]: 29.6 ± 4.3 kg/m2) with severe AS with preserved EF: 33 patients with paradoxical low-flow low-gradient AS (PLFLG AS) and 32 patients with normal flow high-gradient AS (NFHG AS) were prospectively enrolled into the study. Twenty-four subjects (F/M: 14/10; age: 65.4 ± 8.7 years; BMI: 29.6 ± 4.3 kg/m2) who matched as to age, sex, BMI and coronary artery disease (CAD) constituted the control group (CG). Clinical data and markers of vascular remodeling were related to the serum adipokines.

RESULTS

There were no differences in the adipokines concentrations in the AS/CG. Patients with AS and coexisting CAD were characterized by decreased serum adiponectin (9.9 ± 5.5 vs. 12.7 ± 5.8 μg/mL, p = 0.040) and leptin (8.3 ± 7.8 vs. 21.6 ± 17.1 ng/mL, p < 0.001) levels compared to subjects without CAD. There were no differences in the serum adipokines concentrations between patients with PLFLG AS and NFHG AS. Systemic hypertension, diabetes, hyperlipidemia or markers of vascular remodeling did not discriminate adipokines concentrations. Multivariate regression analysis indicated that age (F = 3.02; p = 0.015) and E/E' index (F = 0.87, p = 0.032) were independent predictors of the adiponectin level in the AS group.

CONCLUSIONS

The presence of AS with preserved EF did not change the adipokine serum profile. Adipokines levels were modified by coexisting atherosclerosis but not the typical cardiovascular risk factors or the hemodynamic type of AS.

Role of Adipokines in Cardiovascular Disease

Cardiovascular disease (CVD) is the greatest cause of death, accounting for nearly one-third of all deaths worldwide. The increase in obesity rates over 3 decades is widespread and threatens the public health in both developed and developing countries. Obesity, the excessive accumulation of visceral fat, causes the clustering of metabolic disorders, such as type 2 diabetes, dyslipidemia, and hypertension, culminating in the development of CVD. Adipose tissue is not only an energy storage organ, but an active endocrine tissue producing various biologically active proteins known as adipokines. Since leptin, a central regulator of food intake and energy expenditure, was demonstrated to be an adipose-specific adipokine, attention has focused on the identification and characterization of unknown adipokines to clarify the mechanisms underlying obesity-related disorders. Numerous adipokines have been identified in the past 2 decades; most adipokines are upregulated in the obese state. Adipokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β, and resistin are pro-inflammatory, and exacerbate various metabolic and cardiovascular diseases. However, a small number of adipokines, including adiponectin, are decreased by obesity, and generally exhibit antiinflammatory properties and protective functions against obesity-related diseases. Collectively, an imbalance in the production of pro- and antiinflammatory adipokines in the obese condition results in multiple complications. In this review, we focus on the pathophysiologic roles of adipokines with cardiovascular protective properties.

AdipoRon, an adiponectin receptor agonist, attenuates PDGF-induced VSMC proliferation through inhibition of mTOR signaling independent of AMPK: Implications toward suppression of neointimal hyperplasia

Hypoadiponectinemia is associated with an increased risk of coronary artery disease. Although adiponectin replenishment mitigates neointimal hyperplasia and atherosclerosis in mouse models, adiponectin therapy has been hampered in a clinical setting due to its large molecular size. Recent studies demonstrate that AdipoRon (a small-molecule adiponectin receptor agonist) improves glycemic control in type 2 diabetic mice and attenuates postischemic cardiac injury in adiponectin-deficient mice, in part, through activation of AMP-activated protein kinase (AMPK). To date, it remains unknown as to whether AdipoRon regulates vascular smooth muscle cell (VSMC) proliferation, which plays a major role in neointima formation. In the present study, oral administration of AdipoRon (50mg/kg) in C57BL/6J mice significantly diminished arterial injury-induced neointima formation by ∼57%. Under in vitro conditions, AdipoRon treatment led to significant inhibition of platelet-derived growth factor (PDGF)-induced VSMC proliferation, DNA synthesis, and cyclin D1 expression. While AdipoRon induced a rapid and sustained activation of AMPK, it also diminished basal and PDGF-induced phosphorylation of mTOR and its downstream targets, including p70S6K/S6 and 4E-BP1. However, siRNA-mediated AMPK downregulation showed persistent inhibition of p70S6K/S6 and 4E-BP1 phosphorylation, indicating AMPK-independent effects for AdipoRon inhibition of mTOR signaling. In addition, AdipoRon treatment resulted in a sustained and transient decrease in PDGF-induced phosphorylation of Akt and ERK, respectively. Furthermore, PDGF receptor-β tyrosine phosphorylation, which controls the phosphorylation state of Akt and ERK, was diminished upon AdipoRon treatment. Together, the present findings suggest that orally-administered AdipoRon has the potential to limit restenosis after angioplasty by targeting mTOR signaling independent of AMPK activation.

Significant Association of Serum Adiponectin and Creatine Kinase-MB Levels in ST-Segment Elevation Myocardial Infarction

Aims: Adiponectin, an adipocyte-specific secretory protein, abundantly exists in the blood stream while its concentration paradoxically decreases in obesity. Hypoadiponectinemia is one of risks of cardiovascular diseases. However, impact of serum adiponectin concentration on acute ischemic myocardial damages has not been fully clarified. The present study investigated the association of serum adiponectin and creatine kinase (CK)-MB levels in subjects with ST-segment elevation myocardial infarction (STEMI).

Methods: This study is a physician-initiated observational study and is also registered with the University Hospital Medical Information Network (Number: UMIN 000014418). Patients were admitted to Senri Critical Care Medical Center, given a diagnosis of STEMI, and treated by primary percutaneous coronary intervention (PCI). Finally, 49 patients were enrolled and the association of serum adiponectin, CK-MB, and clinical features were mainly analyzed.

Results: Serum adiponectin levels decreased rapidly and reached the bottom at 24 hours after recanalization. Such reduction of serum adiponectin was inversely correlated with the area under the curve (AUC) of serum CK-MB (p = 0.013). Serum adiponectin concentrations were inversely correlated with AUC of serum CK-MB. In multivariate analysis, serum adiponectin concentration on admission (p = 0.002) and collateral (p = 0.037) were significantly and independently correlated with serum AUC of CK-MB.

Conclusion: Serum AUC of CK-MB in STEMI subjects was significantly associated with serum adiponectin concentration on admission and reduction of serum adiponectin levels from baseline to bottom. The present study may provide a possibility that serum adiponectin levels at acute phase are useful in the prediction for prognosis after PCI-treated STEMI subjects.

Pleiotropic effects of niacin: Current possibilities for its clinical use

Niacin was the first hypolipidemic drug to significantly reduce both major cardiovascular events and mortality in patients with cardiovascular disease. Niacin favorably influences all lipoprotein classes, including lipoprotein[a],and belongs to the most potent hypolipidemic drugs for increasing HDL-C. Moreover, niacin causes favorable changes to the qualitative composition of lipoprotein HDL. In addition to its pronounced hypolipidemic action, niacin exerts many other, non-hypolipidemic effects (e.g., antioxidative, anti-inflammatory, antithrombotic), which favorably influence the development and progression of atherosclerosis. These effects are dependent on activation of the specific receptor HCA2. Recent results published by the two large clinical studies, AIM-HIGH and HPS2-THRIVE, have led to the impugnation of niacin's role in future clinical practice. However, due to several methodological flaws in the AIM-HIGH and HPS2-THRIVE studies, the pleiotropic effects of niacin now deserve thorough evaluation. This review summarizes the present and possible future use of niacin in clinical practice in light of its newly recognized pleiotropic effects.

Nonalcoholic fatty liver disease as a multi-systemic disease

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. NAFLD includes a wide spectrum of liver conditions ranging from simple steatosis to nonalcoholic steatohepatitis and advanced hepatic fibrosis. NAFLD has been recognized as a hepatic manifestation of metabolic syndrome linked with insulin resistance. NAFLD should be considered not only a liver specific disease but also an early mediator of systemic diseases. Therefore, NAFLD is usually associated with cardiovascular disease, chronic kidney disease, type 2 diabetes, obesity, and dyslipidemia. NAFLD is highly prevalent in the general population and is associated with increased cardiovascular morbidity and mortality. The underlying mechanisms and pathogenesis of NAFLD with regard to other medical disorders are not yet fully understood. This review focuses on pathogenesis of NAFLD and its relation with other systemic diseases.

Aortic valve sclerosis is associated with lower serum adiponectin levels

AIMS

The sclerotic lesions of the aortic valve share common features with atherosclerosis. An anti-inflammatory protein, adiponectin, seems to have a protective effect on the cardiovascular system. The goal of our study is to determine adiponectin levels in patients with aortic sclerosis and to compare these values with the control group with similar age and cardiovascular risk profile.

METHODS

Sixty-eight patients with aortic sclerosis and 40 controls were included. Serum adiponectin levels were measured by solid-phase enzyme-linked immunosorbent assay.

RESULTS

There were no significant differences regarding age, sex and other cardiovascular risk factors between groups. Also, mean body mass index values were similar. The rate of mitral annular calcification and left ventricular hypertrophy were significantly higher in patients with aortic sclerosis. Among laboratory variables, high-sensitive C-reactive protein (hsCRP) levels were significantly higher in patients with aortic sclerosis than in those without (4.0 ± 2.9 vs. 2.9 ± 2.3 mg/dl, P = 0.04). Adiponectin levels were found to be significantly lower in aortic sclerosis group than in controls (9.7 ± 4.4 vs. 11.7 ± 4.9 μg/ml, P = 0.034). In the whole group, adiponectin levels were significantly correlated with BMI (r = -0.22, P = 0.02), white blood cell count (r = -0.2, P = 0.03), hsCRP (r = -0.25, P = 0.008), total cholesterol (r = -0.18, P = 0.05), high-density lipoprotein (HDL) cholesterol (r = 0.31, P = 0.001) and triglyceride (r = -0.36, P < 0.001).

CONCLUSION

In patients with aortic sclerosis, serum adiponectin levels were significantly lower compared with those with normal aortic valves. Our findings suggested that adiponectin might play a role in the progression of degenerative aortic valve disease.

Liraglutide treatment causes upregulation of adiponectin and downregulation of resistin in Chinese type 2 diabetes

AIMS

To assess the effect of 16 weeks of liraglutide administration on the plasma levels of adiponectin and resistin in Chinese patients diagnosed with type 2 diabetes mellitus (T2DM).

METHODS

Forty-four subjects were recruited and randomly assigned to once-a-day dosage of either liraglutide, or glimepiride (4 mg) in a double-blinded double-dummy active-controlled study. All treatments were administered in combination with metformin (1 g, twice daily). The efficacy of liraglutide was estimated by measuring and comparing the levels of HbA1c, adiponectin and resistin in the plasma before and after the 16-week treatment.

RESULTS

The plasma level of adiponectin was significantly increased (0.74±0.19 ng/ml, p<0.05) and resistin was significantly lowered (-1.34±0.34 pg/ml, p<0.05) in a dose-dependent manner in the liraglutide group when compared with the glimepiride group (-0.44±0.09 ng/ml of adiponectin and 0.14±0.41 pg/ml of resistin). In contrast, we found no differences in the decrease in HbA1c between the two groups (8.3±1.2% to 7.2±1.1% in NGSP units vs. 8.3±1.0% to 7.3±1.2% in NGSP units; 67±13 mmol/mol to 55±12 mmol/mol vs. 67±11 mmol/mol to 56±13 mmol/mol in IFCC units).

CONCLUSIONS

In Chinese T2DM patients, liraglutide treatment led to increased adiponectin and decreased resistin levels compared to glimepiride-treated subjects, while inducing similar glycemic changes.

Transcardial gradient of adiponectin, interleukin-6 and tumor necrosis factor-α in overweight coronary artery disease patients

BACKGROUND

Obesity is associated with coronary artery disease (CAD), where epicardial adipose tissue (EAT) express proatherogenic cytokines (i.e., interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)) and decreases production of beneficial adiponectin. Studies on endocrine role of EAT are mostly based on assessing cytokines' mRNAs, whereas cytokine blood levels might not readily correlate. In order to get better insight into the endocrine role of thickened EAT in CAD, we assessed transcardial gradient of adiponectin, IL-6 and TNF-α.

METHODS

We assessed anthropometric and ultrasound measures in cohort of fifty nondiabetic subjects (21 CAD and 29 non-CAD). Blood sampled from aortic root and coronary sinus was assayed for adiponectin, IL-6 and TNF-α, using ELISA.

RESULTS

Except thicker EAT in CAD subjects, anthropometric measures were similar (overweight), with higher adiponectin in coronary sinus than in aortic root (p<0.001) in both groups. CAD subjects had lower adiponectin in aortic root (p<0.001) and higher levels of TNF-α in coronary sinus than in aortic root (p=0.05). EAT thickness positively correlated with hip circumference (p=0.038) and negatively correlated with adiponectin levels (for both p<0.05).

CONCLUSIONS

Transcardial gradient of adiponectin in non-CAD and CAD overweight subjects was similar, while latter had lower systemic adiponectin level and thicker EAT. EAT with thickening reaches the threshold level of near-maximal down-regulation of adiponectin and its further thickening is not associated with continued decrease of adiponectin production. In CAD patients levels of TNF-α were higher, but IL-6 were not, and these cytokines might be flush out by lymphatic route.

Association of adiponectin gene polymorphisms with an elevated risk of diabetic peripheral neuropathy in type 2 diabetes patients

OBJECTIVE

In this study, we examined the association between two adiponectin (ADPN) gene polymorphisms, +45T/G and +276G/T, and susceptibility to diabetic peripheral neuropathy (DPN) in type 2 diabetes mellitus (T2DM) patients.

METHODS

A total of 180 T2DM patients were enrolled in this study and assigned to two groups: DPN group (n=90) and non-DPN (NDPN) group (n=90). In addition, 90 healthy subjects were chosen as healthy normal control (NC). The plasma level of ADPN was quantified by ELISA method and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used for genotype analysis of the two ADPN polymorphisms, +45T/G (rs2241766) and +276G/T (rs1501299), in all the study subjects. Statistical analysis of data was performed with SPSS version 20.0 software.

RESULTS

Serum levels of ADPN were markedly reduced in the DPN group compared to NDPN and NC groups (all P<0.05). The frequencies of TT, TG and GG genotypes and the T and G alleles of T45G and G276T polymorphisms in DPN group were significantly different than the NDPN group (all P<0.05). Notably, T45G and G276T polymorphisms were associated with significantly reduced plasma levels of ADPN in DPN and NDPN groups, compared to the NC group (P<0.001). Significant difference in ADPN plasma levels were also observed between TT, TG and GG genotypes of T45G and G276T polymorphisms. Our results indicate that the T allele in +45T/G and +276G/T polymorphisms is correlated with an elevated risk of DPN in T2DM patients. Haplotype analysis showed that GG and GT haplotypes showed a negative relationship with DPN, while TG haplotype positively correlated with risk of DPN in T2DM patients (all P<0.05).

CONCLUSION

Our results show that T45G and G276T polymorphisms of ADPN are associated with a significantly elevated risk of DPN in T2DM patients, likely by down-regulating ADPN serum level.

Serum macrophage migration inhibitory factor levels are associated with angiographically complex coronary lesions in patients with coronary artery disease

BACKGROUND

Rupture of vulnerable plaque with subsequent thrombus formation has been implicated as the most common pathogenic mechanism responsible for acute coronary syndrome (ACS). Angiographic coronary lesion complexity has been reported to reflect plaque vulnerability. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine and might be involved in the pathophysiology of atherosclerotic plaque destabilization.

OBJECTIVE

This study was designed to investigate if serum MIF levels are associated with angiographic coronary lesion complexity in patients with coronary artery disease (CAD).

MATERIALS AND METHODS

A total of 232 consecutive CAD patients and 76 controls were recruited. CAD patients were subdivided according to the presence of ACS (n=138) or stable angina pectoris (SAP) (n=98). Coronary lesion morphology was assessed by coronary angiography. Serum MIF levels were measured by an enzyme-linked immunosorbent assay.

RESULTS

SAP patients had significantly higher serum MIF levels compared with healthy controls, and ACS patients had significantly higher serum MIF levels compared with SAP patients. In SAP patients, serum MIF levels were independently associated with the presence of complex coronary lesion. In ACS patients, serum MIF levels increased in conjunction with the extent of complex lesions.

CONCLUSIONS

Serum MIF levels are a potential biomarker for reflecting the presence and severity of angiographically complex coronary lesion in CAD patients.

Epicardial adipose tissue: far more than a fat depot

Epicardial adipose tissue (EAT) refers to the fat depot that exists on the surface of the myocardium and is contained entirely beneath the pericardium, thus surrounding and in direct contact with the major coronary arteries and their branches. EAT is a biologically active organ that may play a role in the association between obesity and coronary artery disease (CAD). Given recent advances in non-invasive imaging modalities such a multidetector computed tomography (MDCT), EAT can be accurately measured and quantified. In this review, we focus on the evidence suggesting a role for EAT as a quantifiable risk marker in CAD, as well as describe the role EAT may play in the development and vulnerability of coronary artery plaque.

[Markers of visceral adipose tissue metabolic abnormalities in patients with coronary atherosclerosis in relation to the presence of type 2 diabetes mellitus]

AIM

To assess the specific features of visceral adipose tissue metabolism in patients with coronary atherosclerosis, complicated or uncomplicated type 2 diabetes mellitus (T2DM).

MATERIAL AND METHODS

A cohort of 429 patients (325 men and 104 women; mean age, 61.3±9.4 years) with coronary atherosclerosis who had been admitted to the National Research Centre for Preventive Medicine, Ministry of Health of Russia, to undergo coronarography (CG) and to receive high-tech treatments and met the criteria for being included in and excluded from this investigation, was examined. The Gensini scoring scale was used to estimate the magnitude of coronary atherosclerosis from CG RESULTS: Carotid artery duplex ultrasound scanning estimating the intima-media thickness was performed in 48% of the patients. DM was diagnosed from examination results (fasting plasma glucose ≥7.0 mmol/l and glycated hemoglobin >6.5%) and an endocrinologist's report. 94% of the patients took statins.

RESULTS

Overall, 18% of the examinees had DM that was 2.5 times more common in the women than in the men (32.7 and 13.2%, respectively (p=0.000). The diabetic and non-diabetic patients showed no significant differences in age: 62.9±8.3 and 60.9±9.6 years, respectively (p=0.105). There were statistically significant differences in the magnitude of coronary artery atherosclerosis according to the Gensini scale in relation to the presence of T2DM; thus, the median Gensini score was 48 in the diabetic patients and 46 in the persons with no signs of the disease (Mann-Whitney test; p=0.03). Analysis of adipokine levels showed that the median leptin level was significantly higher than that in the male patients with T2DM than in the persons with no signs of the disease. In the patients with T2DM, the median adiponectin level turned out to be significantly lower in both men and women.

CONCLUSION

The coronary atherosclerosis severity rated using the Gensini scale is shown to increase in the presence of T2DM. The probability of detecting obvious (>45%) carotid artery lesion is associated with the presence of DM in both men and women. The male patients with T2DM concurrent with coronary atherosclerosis are noted to have an elevated leptin level, but a lower adiponectin concentration was found in both the men and women.

The Associations of Novel Vitamin D3 Metabolic Gene CYP27A1 Polymorphism, Adiponectin/Leptin Ratio, and Metabolic Syndrome in Middle-Aged Taiwanese Males

Metabolic syndrome (MetS) confers increased risks of cardiovascular disease (CVD). Both vitamin D3 and adipocytokines (especially adiponectin and leptin) have a great impact on CVD and MetS. In vitamin D3 metabolism, the vitamin D3 25-hydroxylase (CYP27A1) and 25-hydroxyvitamin D3 1-alpha-hydroxylase (CYP27B1) are two key enzymes. This study aimed to examine the influence of vitamin D3 CYP27 single nucleotide polymorphisms (SNPs) on adipocytokines and MetS. Cross-sectional data and DNA samples were collected from male volunteers (n = 649, age: 55.7 ± 4.7 years). Two tagging SNPs, CYP27A1 rs4674344 and CYP27B1 rs10877012, were selected from the HapMap project. MetS was significantly associated with the CYP27A1 rs4674344 SNP (P = 0.04) and the ratio of adiponectin/leptin (A/L ratio) was most correlated to the CYP27A1 rs4674344 SNP, appearing to be significantly lower in T-carriers than in AA subjects (3.7 ± 4.0 versus 5.1 ± 6.0, P = 0.001) and significantly negatively associated after adjustment. For each MetS component associated with the CYP27A1 rs4674344 SNP, the A/L ratios were significantly negative in preclinical stage (condition not meeting the individual criteria), except the blood pressure. In conclusion, CYP27A1 rs4674344 SNP, A/L ratio, and MetS are significantly associated and T-carriers might have a higher risk of developing MetS due to low A/L ratios in the preclinical stage.

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.

Association between HMW adiponectin, HMW-total adiponectin ratio and early-onset coronary artery disease in Chinese population

OBJECTIVE

Adiponectin is an adipose-secreting protein that shows atheroprotective property and has inverse relation with coronary artery disease (CAD). High-molecular weight (HMW) adiponectin is reported as the active form of adiponectin. In the present study, we aimed to investigate the association between total adiponectin, HMW adiponectin, HMW-total adiponectin ratio and the severity of coronary atherosclerosis, and to compare their evaluative power for the risk of CAD.

METHODS

Serum levels of total and HMW adiponectin were measured in 382 early-onset CAD (EOCAD) patients and 305 matched controls undergoing coronary angiography by enzyme-linked immunosorbent assay (ELISA). Gensini score was used to evaluate the severity of coronary atherosclerosis.

RESULTS

CAD onset age was positively correlated with HMW adiponectin (r = 0.383, P < 0.001) and HMW-total adiponectin ratio (r = 0.429, P < 0.001) in EOCAD patients. Total and HMW adiponectin and HMW-total adiponectin ratio were all inversely correlated with Gensini score (r = -0.417, r = -0.637, r = -0.578, respectively; all P < 0.001). Multivariate binary logistic regression analysis demonstrated that HMW adiponectin and HMW-total adiponectin ratio were both inversely correlated with the risk of CAD (P < 0.05). ROC analysis indicated that areas under the ROC curves of HMW adiponectin and HMW-total adiponectin ratio were larger than that of total adiponectin (P < 0.05).

CONCLUSIONS

Adiponectin is cardioprotective against coronary atherosclerosis onset in EOCAD patients. HMW adiponectin and HMW-total adiponectin ratio show stronger negative associations with the severity of coronary atherosclerosis than total adiponectin does. HMW adiponectin and HMW-total adiponectin ratio are effective biomarkers for the risk of CAD in Chinese population.

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.

Association between risk factors for vascular dementia and adiponectin

Vascular dementia is caused by various factors, including increased age, diabetes, hypertension, atherosclerosis, and stroke. Adiponectin is an adipokine secreted by adipose tissue. Adiponectin is widely known as a regulating factor related to cardiovascular disease and diabetes. Adiponectin plasma levels decrease with age. Decreased adiponectin increases the risk of cardiovascular disease and diabetes. Adiponectin improves hypertension and atherosclerosis by acting as a vasodilator and antiatherogenic factor. Moreover, adiponectin is involved in cognitive dysfunction via modulation of insulin signal transduction in the brain. Case-control studies demonstrate the association between low adiponectin and increased risk of stroke, hypertension, and diabetes. This review summarizes the recent findings on the association between risk factors for vascular dementia and adiponectin. To emphasize this relationship, we will discuss the importance of research regarding the role of adiponectin in vascular dementia.

Differential behavior between S100A9 and adiponectin in coronary artery disease. Plasma or epicardial fat

AIMS

S100A9 is a new inflammatory marker associated with obesity and cardiovascular disease. Because epicardial adipose tissue (EAT) is an inflammatory source in coronary artery disease (CAD), our aim was to evaluate the S100A9 levels in plasma and EAT and its association with CAD.

MAIN METHODS

Blood, EAT and/or subcutaneous adipose tissue (SAT) biopsies were obtained from 89 patients undergoing elective cardiac surgery. Plasma S100A9 and adiponectin were analyzed by enzyme-linked immunosorbent assay (ELISA) and mRNA expression in both fat pads and were measured by real-time polymerase chain reaction (PCR).

KEY FINDINGS

Our results have shown higher levels of plasma S100A9 in patients with CAD than those without (29 [10-50] vs. 17 [3-28] ng/mL; p=0.007). They were dependent on the number of injured-coronaries (p=0.002) with tendency toward negative association with plasma adiponectin (p=0.139). Although EAT expressed higher levels than SAT and their levels were higher in CAD patients, this last difference did not reach statistical significance. However, there was a positive correlation between neutrophils and EAT S100A9 expression (p=0.007) that may reveal an increase of neutrophil filtration on this fat pad.

SIGNIFICANCE

Plasma S100A9 levels are increased in chronic CAD. The absence of differences regarding EAT S100A9 expression levels indicates a differential inflammatory process between fat tissues and blood in CAD process.

High serum C1q-binding adiponectin levels in male patients with acute coronary syndrome

BACKGROUND

The complement system is part of the immune system in acute coronary syndrome (ACS). Adiponectin has anti-atherogenic and anti-inflammatory properties. Adiponectin and C1q form a protein complex in blood, and serum C1q binding adiponectin (C1q-APN) can be measured. We investigated the comparative evaluation of serum C1q-APN levels in males with ACS, stable angina pectoris (SAP) versus controls.

METHODS

The study subjects were 138 Japanese patients who underwent diagnostic coronary angiography. Blood total adiponectin (Total-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assays. Patients were divided into three groups according to the clinical condition: ACS (n = 78), SAP (n = 41) or normal coronary (NC, n = 19) groups.

RESULTS

Serum C1q levels were significantly higher in the ACS group (54.9±1.2 μg/mL) than in the NC group (48.0±2.5 μg/mL). Although serum Total-APN levels were significantly lower in the SAP and ACS groups, compared with the NC group (7.0±0.5, 7.2±0.3, 10.6±2.0 μg/mL, respectively), serum C1q-APN levels were significantly higher in the ACS group than in the NC and SAP groups (112.1±4.1, 66.3±4.4, 65.7±2.9 units/mL, respectively).

CONCLUSIONS

Patients with ACS had higher serum C1q-APN levels.

TRIAL REGISTRATION

UMIN000002997.

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.

Increased serum C1q-binding adiponectin complex to total-adiponectin ratio in men with multi-vessel coronary disease

BACKGROUND

Adiponectin plays a role as a positive contributor to the stabilization of atherosclerotic plaques. Circulating total adiponectin (Total-APN) levels associates with the number of coronary vessels in men with coronary artery disease (CAD). We recently reported that adiponectin binds to C1q in human blood, and serum C1q-binding adiponectin (C1q-APN) /Total-APN levels are associated with CAD in type 2 diabetic subjects. The present study investigated the relationship between circulating C1q-APN levels and the number of angiographic coronary artery vessel in male subjects.

METHODS

The study subjects were 53 male Japanese patients who underwent diagnostic coronary angiography. Blood total adiponectin (Total-APN), high-molecular weight adiponectin (HMW-APN), C1q-APN and C1q were measured by enzyme-linked immunosorbent assays.

RESULTS

Serum C1q-APN/Total-APN ratio significantly increased in subjects with single and multi-vessel coronary diseases (p = 0.029 for trend, the Kruskal-Wallis test). However, serum Total-APN, HMW-APN, C1q-APN and C1q levels did not correlate with number of diseased coronary vessels.

CONCLUSION

Serum C1q-APN/Total-APN ratio progressively increases in men with single and multi-vessel coronary disease.

TRIAL REGISTRATION

UMIN000002997.

Relationship of plasma adiponectin levels with acute coronary syndromes and coronary lesion severity in north Indian population

Adiponectin is an adipocyte specific cytokine which, in contrast to other adipokines, has been described to have antiinflammatory, antithrombotic, and anti-atherogenic properties. This study evaluates the association between plasma adiponectin levels with acute coronary syndrome (ACS) and angiographic coronary lesion severity in Indian population. Ninety patients included in the study were divided in two groups in 1 : 1 ratio—patients admitted with a diagnosis of ACS and those without ACS. Adiponectin and other risk markers are measured in forty-five consecutive patients in each group undergoing coronary angiography. Patients without ACS were found to have higher adiponectin (16.47 ± 7.88 μg/mL) levels than patients with ACS (9.03 ± 3.13 μg/mL) (P < 0.001). In multiple regression analysis adjusted for all other risk markers, higher adiponectin levels remain positively associated with a lower risk of ACS (P value > 0.002). The greatest increase in risk for ACS was seen at adiponectin levels ≤12.20 μg/mL in study subjects. The adiponectin levels were inversely related to the angiographic severity of coronary artery stenosis increases (P value > 0.02). The study concluded that higher adiponectin levels are independently associated with lower risk of ACS, and patients with severe angiographic coronary artery disease have lower levels of adiponectin.

Usefulness of metabolic syndrome score in the prediction of angiographic coronary artery disease severity according to the presence of diabetes mellitus: relation with inflammatory markers and adipokines

Background

It is a matter of debate whether metabolic syndrome (MS) improves cardiovascular risk prediction beyond the risk associated with its individual components. The present study examined the association of MS score with high sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), resistin, adiponectin, and angiographic coronary artery disease (CAD) severity according to the presence of DM. In addition, the predictive value of various clinical and biochemical parameters were analyzed, including the MS score for angiographic CAD.

Methods

The study enrolled 363 consecutive patients (196 men, 62 ± 11 years of age) who underwent coronary angiography for evaluation of chest pain. Blood samples were taken prior to elective coronary angiography. MS was defined by the National Cholesterol Education Program criteria, with MS score defined as the numbers of MS components. CAD was defined as > 50% luminal diameter stenosis of at least one major epicardial coronary artery. CAD severity was assessed using the Gensini score.

Results

Of the 363 patients studied, 174 (48%) had CAD and 178 (49%) were diagnosed with MS. When the patients were divided into 4 subgroups according to MS score (0–1, 2, 3, 4–5), IL-6 levels and the CAD severity as assessed by the Gensini score increased as MS scores increased. In contrast, adiponectin levels decreased significantly as MS scores increased. When subjects were divided into two groups according to the presence of DM, the relationships between MS score and IL-6, adiponectin, and Gensini score were maintained only in patients without DM. Age, smoking, DM, MS score, and adiponectin independently predicted angiographic CAD in the whole population. However, age is the only predictor for angiographic CAD in patients with DM.

Conclusions

In the presence of DM, neither adipokines nor MS score predicted angiographic CAD. However, in non-diabetic patients, IL-6 and adiponectin showed progressive changes according to MS score, and MS score was an independent predictor of CAD in patients without DM.

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.

Adiponectin, driver or passenger on the road to insulin sensitivity?

Almost 20 years have passed since the first laboratory evidence emerged that an abundant message encoding a protein with homology to the C1q superfamily is highly specifically expressed in adipocytes. At this stage, we refer to this protein as adiponectin. Despite more than 10,000 reports in the literature since its initial description, we seem to have written only the first chapter in the textbook on adiponectin physiology. With every new aspect we learn about adiponectin, a host of new questions arise with respect to the underlying molecular mechanisms. Here, we aim to summarize recent findings in the field and bring the rodent studies that suggest a causal relationship between adiponectin levels in plasma and systemic insulin sensitivity in perspective with the currently available data on the clinical side.

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.

Lower ratio of high-molecular-weight adiponectin level to total may be associated with coronary high-risk plaque

Background

Although high-molecular-weight (HMW) adiponectin is believed to protect against atherosclerosis, the association between HMW adiponectin and the composition of coronary plaques is unknown. We evaluated whether the HMW to total adiponectin ratio was associated with the presence of coronary plaque and its composition using multi-slice computed tomography coronary angiography (MSCTCA).

Methods

Serum total and HMW adiponectin levels were measured in 53 consecutive patients (age, 71) with >50% coronary artery stenosis detected by MSCTCA. A low-attenuation coronary plaque was defined as a plaque with a mean CT density <50 Hounsfield units. Multivariate logistic regression analyses were performed to evaluate the predictors of the presence of low-attenuation coronary plaques, which is thought to be high risk, on CT.

Results

Decreased serum levels of total as well as HMW adiponectin were significantly associated with the presence of at least one calcified or non-calcified coronary artery plaque (total adiponectin level: odds ratio 0.76, 95% CI 0.58–0.99, P = 0.048; HMW adiponectin level: odds ratio 0.65, 95% CI 0.42–0.99, P = 0.047). A low ratio of HMW to total adiponectin was significantly associated with the presence of low-attenuation coronary plaques (4.55, 1.94–21.90, P = 0.049). However, neither the total adiponectin nor the HMW adiponectin level was associated with the presence of low-attenuation coronary plaques.

Conclusion

Lower total or HMW adiponectin levels are associated with the presence of calcified and non-calcified coronary plaques, whereas a lower ratio of HMW to total adiponectin associated with the presence of low-attenuation coronary plaques (thought to be high risk). Measurement of total and HMW adiponectin levels and the HMW to total adiponectin ratio may be useful for risk stratification of coronary artery plaques.

Adiponectin inhibits macrophage tissue factor, a key trigger of thrombosis in disrupted atherosclerotic plaques

OBJECTIVE

Adiponectin (APN) is an adipocytokine with anti-atherogenic and anti-inflammatory properties. Hypoadiponectinemia may associate with increased risk for coronary artery disease (CAD) and acute coronary syndrome (ACS). Tissue factor (TF) initiates thrombus formation and facilitates luminal occlusion after plaque rupture, a common cause of fatal ACS. This study tested the hypothesis that APN influences TF expression by macrophages (MΦ), inflammatory cells found in atheromatous plaques.

METHODS

Human monocyte-derived MΦ or RAW 264.7 cells transfected with TF promoter construct, pretreated with a physiological range of recombinant APN (1-10 μg/ml), received LPS stimulation. TF mRNA and protein levels were quantified by real-time RT-PCR and ELISA. TF pro-coagulant activity was evaluated by one-step clotting assay. TF promoter activity was determined by a dual-luciferase reporter assay. Immunoblot analyses assessed intracellular signaling pathways.

RESULTS

APN treatment suppressed TF mRNA expression and protein production in LPS-stimulated human MΦ, compared to vehicle controls. APN treatment also significantly reduced TF pro-coagulant activity in lysates of LPS-stimulated human MΦ, compared to vehicle controls. Moreover, APN suppressed TF promoter activity in LPS-stimulated MΦ compared to controls. APN suppressed phosphorylation and degradation of IκB-α in LPS-stimulated MΦ.

CONCLUSIONS

APN reduces thrombogenic potential of MΦ by inhibiting TF expression and activity. These observations provide a potential mechanistic link between low APN levels and the thrombotic complications of atherosclerosis.

Plasma adiponectin before and after kidney transplantation

The role of plasma adiponectin (ADPN) in patients with impaired kidney function and following kidney transplantation (Tx) is debated. We aimed to: (i) determine whether pretransplant ADPN level is an independent risk factor for deterioration of glucose tolerance including development of new-onset diabetes mellitus after Tx, (ii) describe which parameters that influence the ADPN concentration before and after Tx. Fifty-seven nondiabetic kidney allograft recipients and 40 nondiabetic uraemic patients were included. The Tx group was examined at baseline and 3 and 12 months after Tx. The uraemic control group was examined twice, separated by 12 months. ADPN levels declined significantly following Tx (P < 0.0001), while estimated glomerular filtration rate (eGFR) increased (P < 0.0005). eGFR, BMI and insulin sensitivity index were independently associated with ADPN in a multivariate regression analysis, whereas an ordinal logistic regression analysis revealed no predictive characteristic of ADPN for aggravation of the glucose tolerance after Tx. In conclusion, kidney transplantation is accompanied by a significant reduction in ADPN concentration. Several factors determine the ADPN concentration before and after Tx including kidney function, insulin resistance, use of immunosuppressive agents and BMI. Pretransplant ADPN level did not predict development of new-onset diabetes mellitus or even deterioration of the glucose tolerance following Tx.

Polymorphisms in the promoter region of the adiponectin (ADIPOQ) gene are presumably associated with transcription level and carcass traits in pigs

The main goal of this study was to screen for polymorphisms in the porcine adiponectin (ADIPOQ) gene promoter, analyse their influence on transcription and identify any association with production traits in pigs. A 1018-bp region of the ADIPOQ gene promoter was analysed in 113 pigs, and seven novel polymorphisms found. Luciferase assays were performed in HEK293 (human embryonic kidney) cells and primary porcine adipose mesenchymal stem cells (pADMSCs) to investigate their affect on promoter activity. A 16-bp indel (c.-106_-91delGCCAGGGGTGTGAGCC) was found to influence promoter strength in vitro. In the HEK293 cell line, the Del/Del genotype showed greater luciferase activity than did the Ins/Ins genotype (P < 0.01). In pADMSCs, the insertion genotype of the ADIPOQ promoter showed greater luciferase activity than did the deletion genotype (P < 0.01). An association study performed for two novel polymorphisms, c.-67G>A and the 16-bp indel, showed significant correlation with loin measurements in Polish Landrace (P < 0.05) and synthetic line 990 (P < 0.01) pigs.

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.

Anti-inflammatory and anti-atherogenic properties of adiponectin

Obesity-related disorders, such as insulin resistance, hypertension and atherosclerosis, are associated with chronic inflammation. Adiponectin is an adipocyte-derived secreted factor that is down-regulated in obese states. Adiponectin exerts the protective actions on obesity-linked diseases, such as insulin resistance and atherosclerosis by attenuating chronic inflammation in its target organs. Adiponectin also exerts the salutary effects on vascular disorders by directly acting on vascular component cells including endothelial cells, smooth muscle cells and macrophages. This review will focus on the role of adiponectin in control of inflammatory responses and atherogenic processes.

Comparison of the efficacy and safety of irbesartan and olmesartan in patients with hypertension (EARTH study)

Fifty-four patients were randomly divided into irbesartan and olmesartan groups. Blood pressure (BP) was significantly decreased in all patients at 12 weeks. In particular, BP in patients who initially received irbesartan showed significant reductions. The equality of variance of BP in the irbesartan group was significantly smaller than that in the olmesartan group at 12 weeks. Blood concentrations of adiponectin were significantly increased in the irbesartan group at 12 weeks. Log [pentraxin-3] in the irbesartan group were significantly decreased. In conclusion, the ability of irbesartan to reduce BP is comparable to that of olmesartan with equivalent safety.

Usefulness of adiponectin as a predictor of all cause mortality in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention

Substantial evidence points to a protective role of adiponectin against atherosclerosis and cardiovascular (CV) disease. However, in the setting of an acute myocardial infarction (AMI), the role of adiponectin has not previously been studied. Consequently, the aim of this study was to investigate the prognostic role of adiponectin after AMI in a large population of patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention. A total of 735 consecutive patients with ST-segment elevation myocardial infarction admitted to a single high-volume invasive heart center and treated with primary percutaneous coronary intervention from September 2006 to December 2008 were included. Blood samples were drawn immediately before the invasive procedure. Plasma adiponectin was measured using a validated immunoassay. End points were all-cause mortality, CV mortality, and admission for new AMI or heart failure. The median follow-up time was 27 months (interquartile range 22 to 33). Patients with high adiponectin (quartile 4) had increased mortality compared to patients with low adiponectin (quartiles 1 to 3) (log-rank p <0.001). After adjustment for conventional risk factors (age, gender, smoking, hypertension, hypercholesterolemia, diabetes, body mass index, C-reactive protein, peak troponin I, creatinine, estimated glomerular filtration rate, previous AMI, multivessel disease, complex lesions, left anterior descending coronary artery lesion, and symptom-to-balloon time) by Cox regression analysis, high adiponectin remained an independent predictor of all-cause mortality (hazard ratio 2.1, 95% confidence interval 1.3 to 3.2, p = 0.001) and CV mortality (hazard ratio 2.6, 95% confidence interval 1.5 to 4.5, p = 0.001). In conclusion, increased plasma adiponectin independently predicts all-cause and CV mortality in patients with ST-segment elevation myocardial infarction treated with primary percutaneous coronary intervention.