Association of chemerin mRNA expression in human epicardial adipose tissue with coronary atherosclerosis

Effect of dapagliflozin on epicardial fat volume in patients with acute coronary syndrome assessed by computed tomography

BACKGROUND AND AIM

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce cardiovascular outcomes; one of the target organs is epicardial adipose tissue, achieving a 10-20% change in patients with diabetes but excluding acute coronary syndrome (ACS), Therefore, the aim was to evaluate the effect of dapagliflozin on epicardial fat in patients with ACS assessed by non-contrast cardiac tomography (CT) and its association with major adverse cardiovascular events (MACE).

METHODS AND RESULTS

This cohort nested case-control study included 52 patients with type 2 diabetes (T2D) and acute myocardial infarction with and without ST-segment elevation. Cases were defined as all patients assigned to dapagliflozin 10 mg, and controls were patients assigned to placebo. Treatment was initiated in-hospital and after percutaneous coronary intervention, and non-contrasted CT was performed at baseline and after 12 months of treatment. In the dapagliflozin group, 4 MACE occurred and 10 in the placebo group (p=0.027), with an odds ratio (OR) of 0.317 (95% CI 0.114-0.882) for the dapagliflozin. Basal epicardial fat volume (EFV) was 117.20 ± 42.65 cm3 in the dapagliflozin group and 123.84 ± 46.9 cm3 in the placebo group, p= 0.596, with an OR of 1.016 (95% CI 0.999-1.033) for MACE. Final EFV was 128.30 ± 37.53 cm3 in the dapagliflozin group and 137.05 ± 50.59 cm3 in the placebo group, p= 0.520.

CONCLUSIONS

Epicardial fat is a risk factor for MACE and increased after 12 months of follow-up in patients with ACS and there was no effect on volume change with the use of dapagliflozin. (ClinicalTrials.gov NCT05998525).

The Role of Chemerin in Metabolic and Cardiovascular Disease: A Literature Review of Its Physiology and Pathology from a Nutritional Perspective

Chemerin is a novel adipokine that plays a major role in adipogenesis and lipid metabolism. It also induces inflammation and affects insulin signaling, steroidogenesis and thermogenesis. Consequently, it likely contributes to a variety of metabolic and cardiovascular diseases, including atherosclerosis, diabetes, hypertension and pre-eclampsia. This review describes its origin and receptors, as well as its role in various diseases, and subsequently summarizes how nutrition affects its levels. It concludes that vitamin A, fat, glucose and alcohol generally upregulate chemerin, while omega-3, salt and vitamin D suppress it. Dietary measures rather than drugs acting as chemerin receptor antagonists might become a novel tool to suppress chemerin effects, thereby potentially improving the aforementioned diseases. However, more detailed studies are required to fully understand chemerin regulation.

Genetic Markers of Insulin Resistance and Atherosclerosis in Type 2 Diabetes Mellitus Patients with Coronary Artery Disease

Type 2 diabetes mellitus (T2DM) is characterized by impaired insulin secretion on a background of insulin resistance (IR). IR and T2DM are associated with atherosclerotic coronary artery disease (CAD). The mechanisms of IR and atherosclerosis are known to share similar genetic and environmental roots. Endothelial dysfunction (ED) detected at the earliest stages of IR might be the origin of atherosclerosis progression. ED influences the secretion of pro-inflammatory cytokines and their encoding genes. The genes and their single nucleotide polymorphisms (SNPs) act as potential genetic markers of IR and atherosclerosis. This review focuses on the link between IR, T2DM, atherosclerosis, CAD, and the potential genetic markers CHI3L1, CD36, LEPR, RETN, IL-18, RBP-4, and RARRES2 genes.

In Silico Identification of Key Genes and Immune Infiltration Characteristics in Epicardial Adipose Tissue from Patients with Coronary Artery Disease

Background

The present study is aimed at identifying the differentially expressed genes (DEGs) and relevant biological processes and pathways associated with epicardial adipose tissue (EAT) from patients with coronary artery disease (CAD). We also explored potential biomarkers using two machine-learning algorithms and calculated the immune cell infiltration in EAT.

Materials and Methods

Three datasets (GSE120774, GSE64554, and GSE24425) were obtained from the Gene Expression Omnibus (GEO) database. The GSE120774 dataset was used to evaluate DEGs between EAT of CAD patients and the control group. Functional enrichment analyses were conducted to study associated biological functions and mechanisms using the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Gene Set Enrichment Analysis (GSEA). After this, the least absolute shrinkage and selection operator (LASSO) and support vector machine recursive feature elimination (SVM-RFE) were performed to identify the feature genes related to CAD. The expression level of the feature genes was validated in GSE64554 and GSE24425. Finally, we calculated the immune cell infiltration and evaluated the correlation between the feature genes and immune cells using CIBERSORT.

Results

We identified a total of 130 upregulated and 107 downregulated genes in GSE120774. Functional enrichment analysis revealed that DEGs are associated with several pathways, including the calcium signaling pathway, complement and coagulation cascades, ferroptosis, fluid shear stress and atherosclerosis, lipid and atherosclerosis, and regulation of lipolysis in adipocytes. TCF21, CDH19, XG, and NNAT were identified as feature genes and validated in the GSE64554 and GSE24425 datasets. Immune cell infiltration analysis showed plasma cells are significantly more numerous in EAT than in the control group (p = 0.001), whereas macrophage M0 (p = 0.024) and resting mast cells (p = 0.036) were significantly less numerous. TCF21, CDH19, XG, and NNAT were correlated with immune cells, including plasma cells, M0 macrophages, and resting mast cells.

Conclusion

TCF21, CDH19, XG, and NNAT might serve as feature genes for CAD, providing new insights for future research on the pathogenesis of cardiovascular diseases.

Epicardial Adipose Tissue: A Novel Potential Imaging Marker of Comorbidities Caused by Chronic Inflammation

The observation of correlations between obesity and chronic metabolic and cardiovascular diseases has led to the emergence of strong interests in “adipocyte biology”, in particular in relation to a specific visceral adipose tissue that is the epicardial adipose tissue (EAT) and its pro-inflammatory role. In recent years, different imaging techniques frequently used in daily clinical practice have tried to obtain an EAT quantification. We provide a useful update on comorbidities related to chronic inflammation typical of cardiac adiposity, analyzing how the EAT assessment could impact and provide data on the patient prognosis. We assessed for eligibility 50 papers, with a total of 10,458 patients focusing the review on the evaluation of EAT in two main contexts: cardiovascular and metabolic diseases. Given its peculiar properties and rapid responsiveness, EAT could act as a marker to investigate the basal risk factor and follow-up conditions. In the future, EAT could represent a therapeutic target for new medications. The assessment of EAT should become part of clinical practice to help clinicians to identify patients at greater risk of developing cardiovascular and/or metabolic diseases and to provide information on their clinical and therapeutic outcomes.

Adipokines, adiposity, and atherosclerosis

Characterized by a surplus of whole-body adiposity, obesity is strongly associated with the prognosis of atherosclerosis, a hallmark of coronary artery disease (CAD) and the major contributor to cardiovascular disease (CVD) mortality. Adipose tissue serves a primary role as a lipid-storage organ, secreting cytokines known as adipokines that affect whole-body metabolism, inflammation, and endocrine functions. Emerging evidence suggests that adipokines can play important roles in atherosclerosis development, progression, as well as regression. Here, we review the versatile functions of various adipokines in atherosclerosis and divide these respective functions into three major groups: protective, deteriorative, and undefined. The protective adipokines represented here are adiponectin, fibroblast growth factor 21 (FGF-21), C1q tumor necrosis factor-related protein 9 (CTRP9), and progranulin, while the deteriorative adipokines listed include leptin, chemerin, resistin, Interleukin- 6 (IL-6), and more, with additional adipokines that have unclear roles denoted as undefined adipokines. Comprehensively categorizing adipokines in the context of atherosclerosis can help elucidate the various pathways involved and potentially pave novel therapeutic approaches to treat CVDs.

Epicardial adipose tissue in contemporary cardiology

Interest in epicardial adipose tissue (EAT) is growing rapidly, and research in this area appeals to a broad, multidisciplinary audience. EAT is unique in its anatomy and unobstructed proximity to the heart and has a transcriptome and secretome very different from that of other fat depots. EAT has physiological and pathological properties that vary depending on its location. It can be highly protective for the adjacent myocardium through dynamic brown fat-like thermogenic function and harmful via paracrine or vasocrine secretion of pro-inflammatory and profibrotic cytokines. EAT is a modifiable risk factor that can be assessed with traditional and novel imaging techniques. Coronary and left atrial EAT are involved in the pathogenesis of coronary artery disease and atrial fibrillation, respectively, and it also contributes to the development and progression of heart failure. In addition, EAT might have a role in coronavirus disease 2019 (COVID-19)-related cardiac syndrome. EAT is a reliable potential therapeutic target for drugs with cardiovascular benefits such as glucagon-like peptide 1 receptor agonists and sodium–glucose co-transporter 2 inhibitors. This Review provides a comprehensive and up-to-date overview of the role of EAT in cardiovascular disease and highlights the translational nature of EAT research and its applications in contemporary cardiology.

In this Review, Iacobellis provides a comprehensive overview of the role of epicardial adipose tissue (EAT) in cardiovascular disease, including coronary artery disease, heart failure and atrial fibrillation, discusses imaging techniques for EAT assessment and highlights the therapeutic potential of targeting EAT in cardiovascular disease.

Epicardial adipose tissue (EAT) has anatomical and functional interactions with the heart owing to the shared circulation and the absence of muscle fascia separating the two organs.

EAT can be clinically measured with cardiac imaging techniques that can help to predict and stratify cardiovascular risk.

Regional distribution of EAT is important because pericoronary EAT and left atrial EAT differently affect the risk of coronary artery diseases and atrial fibrillation, respectively.

EAT has a role in the development of several cardiovascular diseases through complex mechanisms, including gene expression profile, pro-inflammatory and profibrotic proteome, neuromodulation, and glucose and lipid metabolism.

EAT could be a potential therapeutic target for novel cardiometabolic medications that modulate adipose tissue such as glucagon-like peptide 1 receptor agonists and sodium–glucose co-transporter 2 inhibitors.

EAT might be a reservoir of severe acute respiratory syndrome coronavirus 2 and an amplifier of coronavirus disease 2019 (COVID-19)-related cardiac syndrome.

Novel Cardioprotective Effect of L-Carnitine on Obese Diabetic Mice: Regulation of Chemerin and CMKLRI Expression in Heart and Adipose Tissues

Fundamentos

A L-carnitina (LC) tem muitos efeitos benéficos em animais diabéticos e humanos, mas seu efeito regulatório sobre a quemerina como uma citocina inflamatória e seu receptor no estado diabético são desconhecidos.

Objetivos

O presente estudo teve como objetivo investigar o efeito regulatório da LC na expressão do receptor semelhante ao de quimiocina 1 e quemerina (CMKLRI) em tecidos adiposo e cardíaco de camundongos diabéticos.

Métodos

Sessenta camundongos NMARI foram divididos em quatro grupos, incluindo controle, diabético, diabético + suplementação com LC e controle + suplementação com LC. O diabetes foi induzido pela alimentação dos animais com dieta hipercalórica por 5 semanas e injeção de estreptozotocina. Os animais foram tratados com 300 mg/kg de LC por 28 dias. Nos dias 7, 14 e 28 após o tratamento, os níveis de mRNA e proteína da quemerina e CMKLRI nos tecidos cardíacos e adiposos de animais foram determinados utilizando análise por qPCR e ELISA. Os índices de resistência à insulina também foram medidos em todos os grupos experimentais. A diferença com p<0,05 foi considerada significativa.

Resultados

A expressão de quemerina e CMKLRI aumentou nos tecidos cardíaco e adiposo de camundongos diabéticos nos dias 14 e 28 após a indução do diabetes, concomitantemente com a incidência de resistência à insulina e níveis aumentados de quemerina circulante (p<0,05). O tratamento com LC causou uma diminuição significativa na expressão de ambos os genes nos tecidos estudados e redução dos sintomas de resistência à insulina e dos níveis séricos de quemerina (p<0,05).

Conclusão

Os resultados sugerem que o tratamento com LC pode diminuir a expressão de quemerina e CKLR1 em tecidos cardíacos e adiposos de animais experimentais obesos e diabéticos.

Chemerin activity in selected pathological states of human body - A systematic review

Recent studies have revealed that fatty tissue, so far considered an energy storage organ, is also the source of many substances called adipokines, including chemerin which plays many important functions in the body. Chemerin stimulates adipocytes maturation and differentiation, as well as acts as a chemoattractant, which stimulates innate and acquired immunity. This adipokine participates in the early stages of acute inflammation as well as its suppression by reacting with the CMKLR1 receptor. In various diseases associated with inflammatory processes, the level of chemerin in the serum increases. It is also considered a marker for benign and malignant tumors. Explanation of the pathomechanisms involving this adipokine is of a high importance and may contribute to the development of new possibilities in the treatment of many diseases. The article presents the latest information on the role of chemerin in various pathological states, particularly in psoriasis.

Chemerin in inflammatory diseases

Obesity is associated with a series of health problems. Adipocytes are a huge repository of energy as well as an important source of many adipokines. In obesity, adipocytes are dysfunctional with excessive production and secretion of pro-inflammatory adipokines, such as tumor necrosis factor α (TNF-α), leptin, and chemerin. Recent studies have revealed that chemerin plays an important role in modulating physiologic as well as pathophysiologic processes. For example, chemerin stimulates maturation and differentiation of pre-adipocytes, acts as a chemoattractant and facilitates innate and acquired immunity. Furthermore, chemerin participates in the early stage of acute inflammation by reacting with the ChemR23 receptor. In various inflammatory diseases, the serum chemerin is significantly increased. Additionally, chemerin is also considered as an important biomarker for benign and malignant tumors. Thus, elucidating the pathologic mechanisms of chemerin action may facilitate the development of new therapeutic modalities to treat diverse inflammatory diseases. In this review, we summarize current knowledge of chemerin and its role as an important regulator in modulating various inflammatory diseases. Mechanisms underlying chemerin function in diverse diseases are explored to better understand its biochemistry and mechanisms of action.

The role of miR-320 in glucose and lipid metabolism disorder-associated diseases

Glucose and lipids are important nutrients that provide the majority of energy for each organ to maintain homeostasis of the body. With the continuous improvement in living standards, the incidence of metabolic disorder-associated diseases, such as diabetes, hyperlipidemia, and atherosclerosis, is increasing worldwide. Among them, diabetes, which could be induced by both glucose and lipid metabolic disorders, is one of the five diseases with the highest incidence and mortality worldwide. However, the detailed molecular mechanisms underlying glucose and lipid metabolism disorders and target-organ damage are still not fully defined. MicroRNAs (miRNAs) are small, non-coding, single-stranded RNAs, which usually affect their target mRNAs in the cytoplasm by post-transcriptional regulation. Previously, we have found that miR-320 contributed to glucose and lipid metabolism via different signaling pathways. Most importantly, we identified that nuclear miR-320 mediated diabetes-induced cardiac dysfunction by activating the transcription of fatty acid metabolic genes to cause lipotoxicity in the heart. Here, we reviewed the roles of miR-320 in glucose and lipid metabolism and target-organ damage.

Adipose Tissue Immunomodulation: A Novel Therapeutic Approach in Cardiovascular and Metabolic Diseases

Adipose tissue is a critical regulator of systemic metabolism and bodily homeostasis as it secretes a myriad of adipokines, including inflammatory and anti-inflammatory cytokines. As the main storage pool of lipids, subcutaneous and visceral adipose tissues undergo marked hypertrophy and hyperplasia in response to nutritional excess leading to hypoxia, adipokine dysregulation, and subsequent low-grade inflammation that is characterized by increased infiltration and activation of innate and adaptive immune cells. The specific localization, physiology, susceptibility to inflammation and the heterogeneity of the inflammatory cell population of each adipose depot are unique and thus dictate the possible complications of adipose tissue chronic inflammation. Several lines of evidence link visceral and particularly perivascular, pericardial, and perirenal adipose tissue inflammation to the development of metabolic syndrome, insulin resistance, type 2 diabetes and cardiovascular diseases. In addition to the implication of the immune system in the regulation of adipose tissue function, adipose tissue immune components are pivotal in detrimental or otherwise favorable adipose tissue remodeling and thermogenesis. Adipose tissue resident and infiltrating immune cells undergo metabolic and morphological adaptation based on the systemic energy status and thus a better comprehension of the metabolic regulation of immune cells in adipose tissues is pivotal to address complications of chronic adipose tissue inflammation. In this review, we discuss the role of adipose innate and adaptive immune cells across various physiological and pathophysiological states that pertain to the development or progression of cardiovascular diseases associated with metabolic disorders. Understanding such mechanisms allows for the exploitation of the adipose tissue-immune system crosstalk, exploring how the adipose immune system might be targeted as a strategy to treat cardiovascular derangements associated with metabolic dysfunctions.

Adipokines and Inflammation: Focus on Cardiovascular Diseases

It is well established that adipose tissue, apart from its energy storage function, acts as an endocrine organ that produces and secretes a number of bioactive substances, including hormones commonly known as adipokines. Obesity is a major risk factor for the development of cardiovascular diseases, mainly due to a low grade of inflammation and the excessive fat accumulation produced in this state. The adipose tissue dysfunction in obesity leads to an aberrant release of adipokines, some of them with direct cardiovascular and inflammatory regulatory functions. Inflammation is a common link between obesity and cardiovascular diseases, so this review will summarise the role of the main adipokines implicated in the regulation of the inflammatory processes occurring under the scenario of cardiovascular diseases.

Flavonoids in adipose tissue inflammation and atherosclerosis: one arrow, two targets

Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.

Association of Serum Chemerin Levels with Coronary Artery Disease: Pathogenesis and Clinical Research

Recent studies have revealed that chemerin plays an essential role in the development of cardiovascular diseases. Autopsy studies found a strong correlation between the secretion of chemerin in peripheral tissues and aortic and coronary atherosclerosis. Plasma chemerin is a marker of systemic inflammation and is associated with metabolic syndrome. Chemerin plays a vital role in vascular inflammation and atherogenesis. Plasma chemerin levels are increased in patients with dilated cardiomyopathy, and chemerin is associated with left ventricular dysfunction. In this review, we focus on chemerin expression, chemerin processing, its biological function, and its role in the diagnosis of cardiovascular diseases.

Expression of Sfrp5/Wnt5a in human epicardial adipose tissue and their relationship with coronary artery disease

Secreted frizzled-related protein 5 (Sfrp5) primarily acts in combination with wingless-type family member 5a (Wnt5a), to inhibits chronic inflammation and repress atherosclerosis and other metabolic disorders. Epicardial adipose tissue (EAT), surrounding the heart and coronary arteries, has been found to be highly related to the progression of coronary artery disease through adipokines production. However, little is known about EAT-derived Sfrp5 and Wnt5a in humans. We aimed to investigate whether the EAT-derived Sfrp5/Wnt5a levels are altered in patients with CAD. Fifty-eight patients with CAD and 29 patients without CAD who underwent cardiac surgery were enrolled. Serum samples and paired adipose biopsies from EAT and subcutaneous adipose tissue (SAT) were collected, and Sfrp5 and Wnt5a levels were detected. Correlation and multivariate regression analyses were performed to determine the relationship between Sfrp5/Wnt5a expression and CAD and other clinical risk factors. According to the results, the CAD group had lower Sfrp5 and higher Wnt5a levels in EAT and serum (all p < 0.05). Serum Sfrp5 levels were significantly lower in CAD patients with impaired myocardial function. EAT Sfrp5 mRNA levels and serum Sfrp5 levels were both negatively associated with the presence of CAD, after adjustment for known biomarkers, EAT mRNA and serum Wnt5a levels correlated positively with the presence of CAD. Thus, we concluded that low Sfrp5 and high Wnt5a levels are associated with the presence of CAD, independent of other conventional risk factors.

Hematopoietic ChemR23 (Chemerin Receptor 23) Fuels Atherosclerosis by Sustaining an M1 Macrophage-Phenotype and Guidance of Plasmacytoid Dendritic Cells to Murine Lesions-Brief Report

Objective- Expression of the chemokine-like receptor ChemR23 (chemerin receptor 23) has been specifically attributed to plasmacytoid dendritic cells (pDCs) and macrophages and ChemR23 has been suggested to mediate an inflammatory immune response in these cells. Because chemokine receptors are important in perpetuating chronic inflammation, we aimed to establish the role of ChemR23-deficiency on macrophages and pDCs in atherosclerosis. Approach and Results- ChemR23-knockout/knockin mice expressing eGFP (enhanced green fluorescent protein) were generated and after crossing with apolipoprotein E-deficient ( Apoe^-/- ChemR23 ^e/e) animals were fed a western-type diet for 4 and 12 weeks. Apoe^-/- ChemR23 ^e/e mice displayed reduced lesion formation and reduced leukocyte adhesion to the vessel wall after 4 weeks, as well as diminished plaque growth, a decreased number of lesional macrophages with an increased proportion of M2 cells and a less inflammatory lesion composition after 12 weeks of western-type diet feeding. Hematopoietic ChemR23-deficiency similarly reduced atherosclerosis. Additional experiments revealed that ChemR23-deficiency induces an alternatively activated macrophage phenotype, an increased cholesterol efflux and a systemic reduction in pDC frequencies. Consequently, expression of the pDC marker SiglecH in atherosclerotic plaques of Apoe^-/- ChemR23 ^e/e mice was declined. ChemR23-knockout pDCs also exhibited a reduced migratory capacity and decreased CCR (CC-type chemokine receptor)7 expression. Finally, adoptive transfer of sorted wild-type and knockout pDCs into Apoe^-/- recipient mice revealed reduced accumulation of ChemR23-deficient pDCs in atherosclerotic lesions. Conclusions- Hematopoietic ChemR23-deficiency increases the proportion of alternatively activated M2 macrophages in atherosclerotic lesions and attenuates pDC homing to lymphatic organs and recruitment to atherosclerotic lesions, which synergistically restricts atherosclerotic plaque formation and progression.

Leptin Expression in Human Epicardial Adipose Tissue Is Associated with Local Coronary Atherosclerosis

Background

Leptin is an adipokine related to overweight and cardiovascular diseases. However, the leptin expression level in epicardial adipose tissue (EAT) of humans and its association with coronary atherosclerosis has never been investigated.

Material/Methods

Patients receiving cardiac surgery were divided into a coronary artery disease group (CAD group) and a non-CAD group (NCAD group). Blood samples from coronary vein, biopsies of subcutaneous adipose tissue (SAT), and EAT were acquired during the surgery. Serum leptin level and leptin level in EAT and SAT were tested with ELISA, quantitative PCR, and immunohistochemistry and were compared between the CAD group and NCAD group, as well as between stenosis and non-stenosis subgroups. Logistic regression analysis was performed to explore the risk factors for coronary artery stenosis.

Results

No statistically significant differences were found in demographic and clinical data between groups (all P>0.05). Serum leptin concentration and leptin expression in EAT and SAT of the CAD group were much higher in than in the NCAD group (all P<0.05). In subgroup analysis, there was no difference in serum leptin and expression in SAT of stenosis and non-stenosis patients (All P>0.05). The leptin expression level in EAT of stenosis patients was significantly higher than in non-stenosis patients (P=0.0431). By multivariate logistic regression analysis, we demonstrated that leptin expression level in EAT was an independent risk factor for coronary artery stenosis [OR=1.09, 95%CI (1.01±1.18), P=0.031].

Conclusions

Leptin expression in EAT and SAT were both increased for CAD patients. Leptin expression in EAT was an independent risk factor for coronary atherosclerosis in the adjacent artery, while leptin in SAT was not associated.

New insights into different adipokines in linking the pathophysiology of obesity and psoriasis

Psoriasis is a chronic, systemic, hyper-proliferative immune-mediated inflammatory skin disease. The results of epidemiological investigations have shown that psoriasis affects around 2% of the general population worldwide, and the total number of psoriasis patients is more than 6 million in China. Apart from the skin manifestations, psoriasis has been verified to associate with several metabolic comorbidities, such as insulin resistance, diabetes and obesity. However, the underlying mechanism is still not elucidated. Adipocytes, considered as the active endocrine cells, are dysfunctional in obesity which displays increased synthesis and secretion of adipokines with other modified metabolic properties. Currently, growing evidence has pointed to the central role of adipokines in adipose tissue and the immune system, providing new insights into the effect of adipokines in linking the pathophysiology of obesity and psoriasis. In this review, we summarize the current understanding of the pathological role of adipokines and the potential mechanisms whereby different adipokines link obesity and psoriasis. Furthermore, we also provide evidence which identifies a potential therapeutic target aiming at adipokines for the management of these two diseases.

Chemerin-9, a potent agonist of chemerin receptor (ChemR23), prevents atherogenesis

Plasma levels of chemerin, an adipocytokine produced from the adipose tissues and liver, are associated with metabolic syndrome and coronary artery disease (CAD). Chemerin and its analog, chemerin-9, are known to bind to their receptor, ChemR23. However, whether chemerin and chemerin-9 affect atherogenesis remains to be elucidated. We investigated the expression of chemerin and ChemR23 in human coronary arteries and cultured human vascular cells. The effects of chemerin and chemerin-9 on atheroprone phenomena were assessed in human THP1 monocytes, human umbilical vein endothelial cells (HUVECs), and human aortic smooth muscle cells (HASMCs) and aortic lesions in Apoe−/− mice. In patients with CAD, a small amount of ChemR23, but not chemerin, was expressed within atheromatous plaques in coronary arteries. Chemerin and ChemR23 were expressed at high levels in THP1 monocytes, THP1-derived macrophages, and HUVECs; however, their expression in HASMCs was weak. Chemerin and chemerin-9 significantly suppressed the tumor necrosis factor-α (TNF-α)-induced mRNA expression of adhesion and pro-inflammatory molecules in HUVECs. Chemerin and chemerin-9 significantly attenuated the TNF-α-induced adhesion of THP1 monocytes to HUVECs and macrophage inflammatory phenotype. Chemerin and chemerin-9 suppressed oxidized low-density lipoprotein (oxLDL)-induced macrophage foam cell formation associated with down-regulation of CD36 and up-regulation of ATP-binding cassette transporter A1 (ABCA1). In HASMCs, chemerin and chemerin-9 significantly suppressed migration and proliferation without inducing apoptosis. In the Apoe−/− mice, a 4-week infusion of chemerin-9 significantly decreased the areas of aortic atherosclerotic lesions by reducing intraplaque macrophage and SMC contents. Our results indicate that chemerin-9 prevents atherosclerosis. Therefore, the development of chemerin analogs/ChemR23 agonists may serve as a novel therapeutic target for atherosclerotic diseases.

Serum Chemerin as a Novel Prognostic Indicator in Chronic Heart Failure

Background It has been documented that circulating chemerin is associated with inflammation, metabolic syndrome, and coronary artery disease. The present study was aimed to evaluate the prognostic value of serum chemerin in patients with chronic heart failure. Methods and Results We included 834 patients with chronic heart failure in a prospective cohort study and investigated the association between serum chemerin and clinical outcomes using multivariate Cox regression analysis. Patients with higher chemerin levels tended to be older and women and were more likely to experience hypertension, diabetes mellitus, and hyperlipemia. Cox regression analysis showed that chemerin was a significant predictor of major adverse cardiac events (hazard ratio, 1.83; 95% CI, 1.31-2.96) after adjustment for conventional risk factors. Net reclassification and integrated discrimination improvements for major adverse cardiac events were markedly improved by addition of chemerin to the reference model. In addition, chemerin was an independent predictor of all-cause mortality (hazard ratio, 1.67; 95% CI, 1.21-2.73) after multivariable adjustment. Furthermore, the Kaplan-Meier survival analysis revealed that chemerin was a prognostic indicator of major adverse cardiac events in patients with chronic heart failure and NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels above and below the median. Conclusions Our study suggests that chemerin is a novel serum marker for predicting major adverse cardiac events in patients with chronic heart failure.

G-Protein Coupled Receptor Targeting on Myeloid Cells in Atherosclerosis

Atherosclerosis, the underlying cause of the majority of cardiovascular diseases (CVDs), is a lipid-driven, inflammatory disease of the large arteries. Gold standard therapy with statins and the more recently developed proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors have improved health conditions among CVD patients by lowering low density lipoprotein (LDL) cholesterol. Nevertheless, a substantial part of these patients is still suffering and it seems that 'just' lipid lowering is insufficient. The results of the Canakinumab Anti-inflammatory Thrombosis Outcome Study (CANTOS) have now proven that inflammation is a key driver of atherosclerosis and that targeting inflammation improves CVD outcomes. Therefore, the identification of novel drug targets and development of novel therapeutics that block atherosclerosis-specific inflammatory pathways have to be promoted. The inflammatory processes in atherosclerosis are facilitated by a network of immune cells and their subsequent responses. Cell networking is orchestrated by various (inflammatory) mediators which interact, bind and induce signaling. Over the last years, G-protein coupled receptors (GPCRs) emerged as important players in recognizing these mediators, because of their diverse functions in steady state but also and specifically during chronic inflammatory processes - such as atherosclerosis. In this review, we will therefore highlight a selection of these receptors or receptor sub-families mainly expressed on myeloid cells and their role in atherosclerosis. More specifically, we will focus on chemokine receptors, both classical and atypical, formyl-peptide receptors, the chemerin receptor 23 and the calcium-sensing receptor. When information is available, we will also describe the consequences of their targeting which may hold promising options for future treatment of CVD.

Increased circulating chemerin in patients with advanced carotid stenosis

Background

Chemerin is an adipokine which plays a crucial role in atherosclerosis. Here, we examined whether circulating chemerin is enhanced in patients with advanced carotid stenosis.

Methods

Chemerin was quantified in 178 patients prior to carotid end arterectomy (CEA) and in age- and gender-matched controls (n = 163). Chemerin levels were related to anthropometric, clinical and metabolic characteristics of the patients.

Results

Chemerin levels were higher in patients compared to controls (p <  0.001). Chemerin correlated to parameters associated with inflammation such as C-reactive protein (CRP, p <  0.001), leukocyte blood count (p <  0.001) and circulating TNF-α (p = 0.004) in the patients. Chemerin levels did not differ between asymptomatic (n = 93) and symptomatic patients who experienced an ischemic event within 6 months prior to CEA (n = 85). However, in the case of high-grade carotid stenosis (≥ 90%), chemerin levels were higher in symptomatic (n = 44) compared to asymptomatic patients (n = 41, p = 0.014). Chemerin was increased in patients with (n = 50) compared to patients without (n = 128) coronary artery disease (CAD, p = 0.002). A high level of chemerin increases the risk for CAD in patients (p = 0.0013).

Conclusions

Circulating chemerin is increased and correlates to inflammatory parameters in patients with advanced carotid stenosis.

CHEMERIN AND FACTORS RELATED TO CARDIOVASCULAR RISK IN CHILDREN AND ADOLESCENTS: A SYSTEMATIC REVIEW

OBJECTIVE

To review findings on chemerin and factors related to cardiovascular risk in children and adolescents.

DATA SOURCE

A systematic review was performed, according to the standards proposed by the PRISMA guideline, on PubMed, Science Direct, and Lilacs databases. The descriptor "chemerin" was used in combination with "children" and "adolescent", no time limit applied. The research encompassed only original articles written in English, conducted with human subjects - the adult and elderly populations excluded -, as well as literature reviews, brief communications, letters, and editorials.

DATA SYNTHESIS

After independent analyses of the studies by two reviewers, seven articles meeting the eligibility criteria, published between 2012 and 2016, remained for the review. Cross-sectional, prospective, cohort, and case-control studies were included. The importance of chemerin adipokines on the risk factors for cardiovascular disease is demonstrated by its association with obesity and diabetes mellitus, as well as clinical, anthropometric, and biochemical parameters. However, the strength of evidence from these studies is relatively low, due to their heterogeneity, with several limitations such as small samples and consequent lack of representativeness, lack of standardization in dosage methods, cross-sectional design of most studies, and impossibility of extrapolating results.

CONCLUSIONS

The deregulation of chemerin caused by increased adipose tissue may contribute to the development of cardiovascular diseases, suggesting that this adipokine may play a significant role in early identification of individuals at risk.

Human Epicardial Adipose Tissue cTGF Expression is an Independent Risk Factor for Atrial Fibrillation and Highly Associated with Atrial Fibrosis

Epicardial adipose tissue (EAT) is associated with the incidence, perpetuation, and recurrence of atrial fibrillation (AF), with elusive underlying mechanisms. We analyzed adipokine expression in samples from 20 patients with sinus rhythm (SR) and 16 with AF. Quantitative real-time PCR showed that connective tissue growth factor (cTGF) expression was significantly higher in EAT than in subcutaneous adipose tissue (SAT) or paracardial adipose tissue (PAT) from patients with AF, and in EAT from patients with SR (P < 0.001). Galectin-3 expression was significantly higher in EAT than in SAT or PAT (P < 0.001), with no significant differences between patients with AF and SR (P > 0.05). Leptin and vaspin expression were lower in EAT than in PAT (P < 0.001). Trichrome staining showed that the fibrosis was much more severe in patients with AF than SR (P < 0.001). We found a linear relationship between cTGF mRNA expression level and collagen volume fraction (y = 1.471x + 27.330, P < 0.001), and logistic regression showed that cTGF level was an independent risk factor for AF (OR 2.369, P = 0.027). In conclusion, highly expressed in EAT, cTGF is associated with atrial fibrosis, and can be an important risk factor for AF.

Association between chemerin, omentin-1 and risk of heart failure in the population-based EPIC-Potsdam study

The adipokines chemerin and omentin-1 have been suggested to influence cardiovascular function. The study aimed to investigate the longitudinal association between chemerin, omentin-1 concentrations and risk of incident heart failure (HF), respectively. We conducted a case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort (n = 27548) including a randomly drawn subsample and all incident HF cases during a mean follow-up of 8.2 ± 1.5 years. A total of 212 incident HF cases and 2168 individuals free of HF cases were included in the study. After multivariable adjustment for established cardiovascular risk factors chemerin was strongly associated with risk of HF (HR per doubling chemerin: 4.91; 95%-CI: 2.57-9.39; p < 0.0001). Omentin-1 was not significantly related to HF risk in the overall study population. However, the association between omentin-1 and HF risk was modified by prevalent coronary heart disease (CHD), showing that the shape of the association was linear in participants without prevalent CHD (HR doubling omentin-1: 2.11; 95%-CI: 1.36-3.27; p linear = 0.0009) and U-shaped in participants with pre-existing CHD (p non-linear = 0.006). Our study provides first evidence for a strong positive association between chemerin and risk of HF. The association between the adipokine omentin-1 and risk of HF may differ according to pre-existing CHD.

Investigating interactions between epicardial adipose tissue and cardiac myocytes: what can we learn from different approaches?

Heart disease is a major cause of morbidity and mortality throughout the world. Some cardiovascular conditions can be modulated by lifestyle factors such as increased exercise or a healthier diet, but many require surgical or pharmacological interventions for their management. More targeted and less invasive therapies would be beneficial. Recently, it has become apparent that epicardial adipose tissue plays an important role in normal and pathological cardiac function, and it is now the focus of considerable research. Epicardial adipose tissue can be studied by imaging of various kinds, and these approaches have yielded much useful information. However, at a molecular level, it is more difficult to study as it is relatively scarce in animal models and, for practical and ethical reasons, not always available in sufficient quantities from patients. What is needed is a robust model system in which the interactions between epicardial adipocytes and cardiac myocytes can be studied, and physiologically relevant manipulations performed. There are drawbacks to conventional culture methods, not least the difficulty of culturing both cardiac myocytes and adipocytes, each of which has special requirements. We discuss the benefits of a three-dimensional co-culture model in which in vivo interactions can be replicated.

LINKED ARTICLES

This article is part of a themed section on Molecular Mechanisms Regulating Perivascular Adipose Tissue - Potential Pharmacological Targets? To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.20/issuetoc.

Osteoactivin regulates head and neck squamous cell carcinoma invasion by modulating matrix metalloproteases

Nearly 60% of patients with head and neck squamous cell carcinoma (HNSCC) die of metastases or locoregional recurrence. Metastasis is mediated by cancer cell migration and invasion, which are in part dependent on extracellular matrix degradation by matrix metalloproteinases. Osteoactivin (OA) overexpression plays a role in metastases in several malignancies, and has been shown to upregulate matrix metalloproteinase (MMP) expression and activity. To determine how OA modulates MMP expression and activity in HNSCC, and to investigate OA effects on cell invasion, we assessed effects of OA treatment on MMP mRNA and protein expression, as well as gelatinase and caseinolytic activity in HNSCC cell lines. We assessed the effects of OA gene silencing on MMP expression, gelatinase and caseinolytic activity, and cell invasion. OA treatment had differential effects on MMP mRNA expression. OA treatment upregulated MMP-10 expression in UMSCC14a (p = 0.0431) and SCC15 (p < 0.0001) cells, but decreased MMP-9 expression in UMSCC14a cells (p = 0.0002). OA gene silencing decreased MMP-10 expression in UMSCC12 cells (p = 0.0001), and MMP-3 (p = 0.0005) and -9 (p = 0.0036) expression in SCC25 cells. In SCC15 and SCC25 cells, OA treatment increased MMP-2 (p = 0.0408) and MMP-9 gelatinase activity (p < 0.0001), respectively. OA depletion decreased MMP-2 (p = 0.0023) and -9 (p < 0.0001) activity in SCC25 cells. OA treatment increased 70 kDa caseinolytic activity in UMSCC12 cells consistent with tissue type plasminogen activator (p = 0.0078). OA depletion decreased invasive capacity of UMSCC12 cells (p < 0.0001). OA's effects on MMP expression in HNSCC are variable, and may promote cancer cell invasion.

Serum CXCL10 and CXCL12 chemokine levels are associated with the severity of coronary artery disease and coronary artery occlusion

BACKGROUND

Cardiovascular disease constitutes a major cause of death worldwide. Inflammation plays an important role in atherosclerosis formation, coronary artery disease progression, acute coronary thrombosis and occlusion. Chemokines are inflammatory mediators disposing several bio-functions, as leukocyte migration towards inflammatory signals and vascular injuries. The present study was designed to evaluate the potential correlation between serum levels of chemokines CXCL-10 and CXCL-12 and the degree of coronary artery occlusion.

METHODS

Eighty eight patient candidates for coronary angiography with coronary artery disease symptoms and potentially high risk of coronary artery occlusion were recruited. Chemokine serum levels were measured with the ELISA method and patients underwent coronary angiography. All patients with coronary artery disease (CAD) were divided into four groups according to the Gensini score. Data were presented as mean±SD. All P values <0.05 were considered significant.

RESULTS

Our demographic data showed that of the 88 patients, 46 were male and 42 female. The mean age of patients was 57.95±11.13. Following increased coronary artery occlusion the serum levels of chemokines were significantly increased (CXCL-10 and CXCL-12; P<0.0001 and P<0.0001, respectively).

CONCLUSION

In this novel study, a significant correlation between the serum levels of CXCL-10 and CXCL-12 and the severity of coronary artery occlusion was found. This could be attributed to the role of these chemokines in the processes of angiogenesis and angiostasis, a biological phenomenon that can play key role in the development of collateral circulation.

Chemerin Stimulates Vascular Smooth Muscle Cell Proliferation and Carotid Neointimal Hyperplasia by Activating Mitogen-Activated Protein Kinase Signaling

Vascular neointimal hyperplasia and remodeling arising from local inflammation are characteristic pathogeneses of proliferative cardiovascular diseases, such as atherosclerosis and post angioplasty restenosis. The molecular mechanisms behind these pathological processes have not been fully determined. The adipokine chemerin is associated with obesity, metabolism, and control of inflammation. Recently, chemerin has gained increased attention as it was found to play a critical role in the development of cardiovascular diseases. In this study, we investigated the effects of chemerin on the regulation of vascular smooth muscle cells and carotid neointimal formation after angioplasty. We found that circulating chemerin levels increased after carotid balloon injury, and that knockdown of chemerin significantly inhibited the proliferative aspects of vascular smooth muscle cells induced by platelet-derived growth factor-BB and pro-inflammatory chemokines in vitro as well as prohibited carotid neointimal hyperplasia and pro-inflammatory chemokines in vivo after angioplasty. Additionally, inhibition of chemerin down-regulated the expression of several proteins, including phosphorylated p38 mitogen-activated protein kinase, phosphorylated extracellular signal regulated kinase 1/2, nuclear factor-kappa B p65, and proliferation cell nuclear antigen. The novel finding of this study is that chemerin stimulated vascular smooth muscle cells proliferation and carotid intimal hyperplasia through activation of the mitogen-activated protein kinase signaling pathway, which may lead to vascular inflammation and remodeling, and is relevant to proliferative cardiovascular diseases.

Tumor Necrosis Factor-Alpha and the ERK Pathway Drive Chemerin Expression in Response to Hypoxia in Cultured Human Coronary Artery Endothelial Cells

BACKGROUND

Chemerin, a novel adipokine, plays a role in the inflammation status of vascular endothelial cells. Hypoxia causes endothelial-cell proliferation, migration, and angiogenesis. This study was aimed at evaluating the protein and mRNA expression of chemerin after exposure of human coronary artery endothelial cells (HCAECs) to hypoxia.

METHODS AND RESULTS

Cultured HCAECs underwent hypoxia for different time points. Chemerin protein levels increased after 4 h of hypoxia at 2.5% O2, with a peak of expression of tumor necrosis factor-alpha (TNF-alpha) at 1 h. Both hypoxia and exogenously added TNF-alpha during normoxia stimulated chemerin expression, whereas an ERK inhibitor (PD98059), ERK small interfering RNA (siRNA), or an anti-TNF-alpha antibody attenuated the chemerin upregulation induced by hypoxia. A gel shift assay indicated that hypoxia induced an increase in DNA-protein binding between the chemerin promoter and transcription factor SP1. A luciferase assay confirmed an increase in transcriptional activity of SP1 on the chemerin promoter during hypoxia. Hypoxia significantly increased the tube formation and migration of HCAECs, whereas PD98059, the anti-TNF-alpha antibody, and chemerin siRNA each attenuated these effects.

CONCLUSION

Hypoxia activates chemerin expression in cultured HCAECs. Hypoxia-induced chemerin expression is mediated by TNF-alpha and at least in part by the ERK pathway. Chemerin increases early processes of angiogenesis by HCAECs after hypoxic treatment.

Association between omentin-1 expression in human epicardial adipose tissue and coronary atherosclerosis

Background

Omentin-1, a novel adipocytokine mainly expressed in visceral adipose tissue, has been found to inhibit the inflammatory response and improve insulin resistance as well as other obesity-related disorders. This study investigated the association between omentin-1 expression in human epicardial adipose tissue (EAT) and coronary atherosclerosis.

Methods

Serum samples, and paired biopsies from EAT and subcutaneous adipose tissue (SAT), were obtained from patients with and without coronary artery disease (CAD, n = 28 and NCAD, n = 12, respectively) during elective cardiac surgery. Coronary angiography was performed to identify CAD presence. Serum omentin-1 and adiponectin levels were measured by ELISA. mRNA expression of omentin-1 and adiponectin was detected in adipose tissue by quantitative real-time PCR, and omentin-1 protein expression was evaluated by immunohistochemistry. Correlation and multivariate linear regression analyses were performed to determine the association between omentin-1 expression and clinical risk factors.

Results

mRNA and protein expression of omentin-1 were higher in EAT than paired SAT in patients with CAD and NCAD. Compared with NCAD patients, CAD patients had lower omentin-1 and adiponectin mRNA levels in EAT and serum levels as well as lower omentin-1 protein levels. Among patients with CAD, omentin-1 expression was lower in EAT surrounding coronary segments with stenosis than those without stenosis, in terms of mRNA and protein, whereas adiponectin mRNA level in EAT did not seem to differ between stenotic and non-stenotic coronary segments in CAD patients. In multivariate linear regression analysis, CAD was an independent predictor of EAT omentin-1 mRNA expression (beta = −0.57, 95 % CI −0.89 to −0.24; P = 0.001) and serum omentin-1 levels (beta = −0.35, 95 % CI −0.67 to −0.03; P = 0.036).

Conclusions

Circulating and EAT-derived omentin-1 levels were reduced in patients with CAD. Omentin-1 expression in patients with CAD was lower in EAT adjacent to coronary stenotic segments than non-stenotic segments.

The comparison of chemerin, adiponectin and lipid profile indices in obese and non-obese adolescents

AIMS

The growing prevalence of obesity and its related metabolic disorders in adolescents shows the necessity of urgent focus on the related factors. Adipocytes secretions and their pro- or anti-inflammatory roles play effective roles in adipocytes metabolism. We assessed the relation between adiponectin, chemerin and lipid profile in hit phase of life.

METHODS

This case-control study conducted on 78 adolescent girls, divided based on BMI percentile. Serum chemerin, adiponectin, lipid profile and body fat mass were measured. Data were analyzed using Pearson correlation test. The interactive relation between these variables was assessed using Structural Equation Modeling (SEM). Data were analyzed using SPSS software and AMOS software.

RESULTS

Chemerin were correlated significantly with triglyceride (r=0.584 versus r=0.319), HDL-cholestrol (r=-0.323 versus r=-0.335), LDL-cholestrol (r=0.368 versus r=0.327) and fat mass (r=0.372 versus r=0.357) in obese versus non-obese girls; while the mentioned correlation were non-significant with total cholesterol in obese group (r=0.233 versus r=0.336). Furthermore, there were significant association between adiponectin and triglyceride (r=-0.404 versus r=-0.317), HDL-cholesterol (r=0.332 versus r=0.316) and fat mass (r=-0.529 versus r=-0.346) in obese versus non-obese girls, respectively.

CONCLUSION

There were positive associations between lipid profile components and serum chemerin levels. Adiponectin levels were in positive correlation with HDL-cholesterol concentrations. Chemerin showed positive correlations with potent health threatening components of lipid profile including triglyceride and cholesterol levels in adolescents.

Chemerin is not associated with subclinical atherosclerosis markers in prediabetes and diabetes

OBJECTIVE

Chemerin is a novel adipokine that is correlated with adipocyte differentiation, glucose metabolism, and inflammation. We aimed to investigate the relation between serum chemerin level and subclinical atherosclerosis markers as exemplified by brachial artery pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), epicardial fat thickness (EFT), and carotid plaque presence in diabetes and prediabetes.

METHODS

Age-, body mass index (BMI)-, and gender-matched patients with type 2 DM (n=30), prediabetes (n=25), and normal glucose tolerance (n=25) were included in this cross-sectional study. Serum chemerin level, lipid parameters, glucose metabolism marker, baPWV, CIMT, EFT, and anthropometric were recorded. The independent risk factors for atherosclerosis markers were determined by linear and/or multiple logistic regression analysis.

RESULTS

baPWV and carotid plaque presence were higher in the diabetes group than in prediabetes and control groups (p=0.039 and p=0.035 respectively), whereas serum chemerin levels were similar among groups (p=0.338). Chemerin levels were not correlated with PWV, CIMT, and epicardial fat thickness overall or in the subgroups. Overall and in the diabetes group, chemerin levels were positively correlated with the key components of metabolic syndrome as BMI, total body fat percentage, waist circumference, triglyceride, and systolic and diastolic blood pressure (BP). After adjusting for age, gender, and BMI, only the association between chemerin and systolic BP remained significant. Chemerin was not found as an independent risk factor for predicting atherosclerosis in diabetes and prediabetes.

CONCLUSION

Chemerin is not a predictive marker for atherosclerosis in diabetes and prediabetes, but correlates well with key aspects of the metabolic syndrome particularly in diabetes.

Transcriptome and Molecular Endocrinology Aspects of Epicardial Adipose Tissue in Cardiovascular Diseases: A Systematic Review and Meta-Analysis of Observational Studies

The objective of this study was to perform a systematic review of published literature on differentially expressed genes (DEGs) in human epicardial adipose tissue (EAT) to identify molecules associated with CVDs. A systematic literature search was conducted in PubMed, SCOPUS, and ISI Web of Science literature databases for papers published before October 2014 that addressed EAT genes and cardiovascular diseases (CVDs). We included original papers that had performed gene expressions in EAT of patients undergoing open-heart surgery. The Reporting Recommendations for Tumor Marker Prognostic Studies (PRIMARK) assessment tool was also used for methodological quality assessment. From the 180 papers identified by our initial search strategy, 40 studies met the inclusion criteria and presented DEGs in EAT samples from patients with and without CVDs. The included studies reported 42 DEGs identified through comparison of EAT-specific gene expression in patients with and without CVDs. Among the 42 DEGs, genes involved in regulating apoptosis had higher enrichment scores. Notably, interleukin-6 (IL-6) and tumor protein p53 (TP53) were the main hub genes in the network. The results suggest that regulation of apoptosis in EAT is critical for CVD development. Moreover, IL-6 and TP53 as hub genes could serve as biomarkers and therapeutic targets for CVDs.

Association of Serum Chemerin Levels with Acute Ischemic Stroke and Carotid Artery Atherosclerosis in a Chinese Population

BACKGROUND

The aim of this study was to examine the association between serum level of chemerin with AIS and carotid artery atherosclerosis, and to investigate the level of chemerin as a potential novel cerebrovascular risk factor.

MATERIAL AND METHODS

We compared the serum chemerin levels and cerebrovascular parameters between 70 AIS patients and 70 non-AIS subjects in a Chinese population. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of serum chemerin. The state of carotid artery plaques in the AIS group was detected by color Doppler ultrasound. We used SPSS software for statistical analysis.

RESULTS

Compared with the non-AIS group, serum level of chemerin in the AIS group increased significantly (p<0.01). Multivariable logistic regression suggested that serum chemerin level, neutrophil count, and BMI were independent risk factors for AIS (p<0.05). Compared with the non-unstable plaque group, there were significant differences from the unstable plaque group in serum chemerin level (p<0.01). Multivariable logistic regression analysis revealed that the LDL-C, FIB, and serum chemerin levels were independent risk factors for carotid artery plaque instability (P<0.05). The levels of serum chemerin in the subjects with no carotid artery plaque were significantly lower than in those with carotid artery plaques of 2 and ≥3 (P=0.013; P=0.01).

CONCLUSIONS

The results of this study suggest that the serum chemerin level may be an independent risk factor for AIS and carotid artery plaque instability in Chinese populations.

Circulating chemerin levels elevated in dilated cardiomyopathy patients with overt heart failure

BACKGROUND

Recent evidence demonstrated that the circulating concentrations of adipokine are related to the presence of heart failure secondary to ischemic heart disease and dilated cardiomyopathy (DCM). However, the plasma concentrations of chemerin in patients with DCM have yet to be investigated.

METHODS

The present study enrolled 109 DCM patients with typical symptoms of heart failure and 60 healthy controls and measured plasma concentrations of chemerin, IL-6 and TNF-α using enzyme-linked immunosorbent assay. Left ventricular end-diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) were measured using a GE ViVid E7 ultrasonography machine.

RESULTS

Plasma chemerin, IL-6 and TNF-α concentrations were significantly higher in DCM patients compared to the control group. A correlation analysis revealed that plasma chemerin concentrations were positively correlated with the concentrations of IL-6 (R=0.270, P=0.004), TNF-α (R=0.302, P=0.001), C-reactive protein (CRP) (R=0.256, P=0.004), N-terminal pro-brain natriuretic peptide (NT-proBNP) (R=0.386, P=0.000), and LVEDD (R=0.212, P=0.027) but negatively correlated with LVEF (R=-0.543, P=0.000). Furthermore, chemerin (OR 1.102, 95% CI 1.052 to 1.153; p=0.000) was independently associated with the presence of DCM before NT-proBNP was added in the multivariable regression model.

CONCLUSIONS

The results indicate that chemerin is a novel biomarker of DCM.

Chemerin and prediction of Diabetes mellitus type 2

OBJECTIVE

Insulin resistance and subclinical inflammation are characteristics in the development of type 2 diabetes mellitus (T2DM). The adipokine chemerin has been associated with both factors. The aim of this study was to analyse whether chemerin predicts T2DM.

DESIGN

Blood samples of 440 participants of the Metabolic-Syndrome Berlin-Potsdam (MesyBepo) follow-up study without diabetes at baseline were available for chemerin measurement. Mean follow-up of participants was 5·3 years. Glucose metabolism was analysed using oral glucose tolerance test including insulin measurements. Chemerin was measured using a commercially available ELISA.

RESULTS

Thirty-five individuals developed T2DM during follow-up. Chemerin predicted incident T2DM (Chemerin 1. Tertile: reference, 2. Tertile: OR 2·33 [0·68-7·95]; Chemerin 3. Tertile: OR 3·42 [1·01-11·58] after adjustment for age, sex, BMI, follow-up time, HbA1c, HOMA-IR and WHR). In a secondary analysis, chemerin also predicted worsening of fasting glucose and HbA1c (adjusted for age, sex, BMI, time of follow-up, WHR, HDL cholesterol and triglycerides).

CONCLUSIONS

Our data suggest that chemerin is a weak predictor of T2DM.

Association of chemerin levels with anthropometric indexes and C-reactive protein in obese and non-obese adolescents

BACKGROUND

Obesity is a low-grade chronic inflammation. This epidemic is growing in different age groups including adolescents. It is accompanied with a decrease in the age for incidence of obesity-related disorders. Chemerin, as a chemokine and stimulator of anti-inflammatory adiponectin, links immune system, adipose tissue and inflammation. It may be useful in predicting obesity in the hit phase of life. This study aims to assess serum chemerin and adiponectin in relation to the inflammation and obesity indices.

METHODS

This case-control study was conducted on 82 adolescent girls, aged12-18 years. They were categorized based on the percentiles of the body mass index (BMI).Serum chemerin, adiponectin, high-sensitive C-reactive protein (Hs-CRP), body fat mass and its percent, waist circumference (WC) ,hip circumference (HC) were measured; BMI and waist-to-hip ratio (WHR)were calculated. Data were analyzed by independent Student's t-test and Pearson correlation; path analysis was conducted, as well.

RESULTS

We found a negative significant association between chemerin and adiponectin levels in both obese and non-obese groups(r =-0.387, P = 0.014 vs. r = 0.362, respectively, P = 0.018). Serum chemerin was higher in obese than in non-obese adolescents (441.83 ± 47.79 vs. 409.30 ± 66.12 µg /l, respectively, P = 0.012), whereas mean adiponectin level was lower in obese participants than in the other group (4.79 ± 0.94 versus 5.2 ± 0.53µg/ml, respectively, P = 0.016). Chemerin concentrations had significant positive correlation with Hs-CRP levels, BMI, WC, HC, WHR, body fat mass and its percent (P < 0.05).

CONCLUSION

Chemerin concentrations were associated with and adiponectin levels in obese girl adolescents, negatively. Hs-CRP, BMI, WC, HC, WHR, body fat mass and its' percent were in positive relation with chemerin levels, and inverse association with serum adiponectin concentrations. Our findings suggest that chemerin can be considered as an early marker of the inflammatory process in obesity.

Chemerin/chemR23 axis in inflammation onset and resolution

Chemerin is an adipokine secreted by adipocytes and associated with obesity, insulin resistance and metabolic syndrome. Different chemerin fragments with pro- or anti-inflammatory action can be produced, depending on the class of proteases predominating in the microenvironment. Chemerin binds to three receptors, especially to chemR23, expressed on various cells, as dendritic cells, macrophages and natural killer cells, regulating chemotaxis towards the site of inflammation and activation status. Recently, the chemerin/chemR23 axis has attracted particular attention for the multiple roles related to the control of inflammation, metabolism and cancerogenesis in different organs and systems as lung (allergy and cancer), skin (psoriasis, lupus, cancer, wound repair), cardiovascular system (lipid profile and atherosclerosis), reproductive apparatus (polycystic ovary syndrome, follicular homoeostasis), and digestive tract (inflammatory bowel diseases and cancer). This pathway may regulate immune responses by contributing both to the pathogenesis of inflammatory diseases and to the resolution of acute inflammation. Thus, chemerin-derived peptides or other substances that may affect the chemerin/chemR23 axis could be used in the future for the treatment of many diseases, including cancer at different sites.

Chemerin is a novel biomarker of acute coronary syndrome but not of stable angina pectoris

BACKGROUND

Recent evidence demonstrated that the circulating adipokines were associated with the onset of acute coronary syndrome (ACS) including unstable angina pectoris (UAP) and acute myocardial infarction (AMI). As a novel adipokine, chemerin has been related to atherosclerosis and the presence of coronary artery disease. However, the plasma levels of chemerin in patients with ACS have yet to be investigated.

METHODS

Plasma levels of chemerin and adiponectin were measured by an enzyme-linked immunosorbent assay (ELISA) in 60 patients with stable angina pectoris (SAP), 60 patients with UAP, 60 patients with AMI and 40 control patients. Left ventricular end-diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) were measured using a GE ViVid E7 ultrasonography machine, and the severity of coronary stenosis in patients was estimated with a Gensini coronary score following coronary angiography.

RESULTS

Plasma chemerin levels were significantly higher in ACS patients than in the control and SAP groups, while plasma adiponectin levels were significantly lower in ACS patients than the control group. A correlation analysis revealed that plasma chemerin levels were positively correlated with the levels of C-reactive protein (CRP) (r = 0.29, P < 0.01) and LVEDD (r = 0.27, P < 0.01) but negatively correlated with LVEF (r = -0.45, P < 0.01) and that plasma adiponectin levels were positively correlated with LVEF (r = 0.53, P < 0.01) but negatively correlated with CRP (r = -0.33, P < 0.01) and LVEDD (r = -0.30, P < 0.01). Although significant correlations between chemerin, adiponectin and BMI or the Gensini coronary score were found in patients with SAP, neither chemerin nor adiponectin was correlated with BMI and the Gensini coronary score in patients with ACS. Furthermore, both chemerin (OR 1.103, 95% CI 1.065 to 1.142; P = 0.001) and adiponectin (OR 0.871, 95% CI 0.776 to 0.970; P = 0.018) were independently associated with the presence of ACS.

CONCLUSIONS

Chemerin is a novel biomarker of acute coronary syndrome but not of stable angina pectoris.

Correlation between pericardial, mediastinal, and intrathoracic fat volumes with the presence and severity of coronary artery disease, metabolic syndrome, and cardiac risk factors

AIMS

To investigate the association of pericardial, mediastinal, and intrathoracic fat volumes with the presence and severity of coronary artery disease (CAD), metabolic syndrome (MS), and cardiac risk factors (CRFs).

METHODS AND RESULTS

Two hundred and sixteen consecutive patients who underwent cardiac magnetic resonance (CMR) imaging and had a coronary angiogram within 12 months of the CMR were studied. Fat volume was measured by drawing region of interest curves, from short-axis cine views from base to apex and from a four-chamber cine view. Pericardial fat, mediastinal fat, intrathoracic fat (addition of pericardial and mediastinal fat volumes), and fat ratio (pericardial fat/mediastinal fat) were analysed for their association with the presence and severity of CAD (determined based on the Duke CAD Jeopardy Score), MS, CRFs, and death or myocardial infarction on follow-up. Pericardial fat volume was significantly greater in patients with CAD when compared with those without CAD [38.3 ± 25.1 vs. 31.9 ± 21.4 cm(3) (P = 0.04)]. A correlation between the severity of CAD and fat volume was found for pericardial fat (β = 1, P < 0.01), mediastinal fat (β = 1, P = 0.03), intrathoracic fat (β = 2, P = 0.01), and fat ratio (β = 0.005, P = 0.01). These correlations persisted for all four thoracic fat measurements even after performing a stepwise linear regression analysis for relevant risk factors. Patients with MS had significantly greater mediastinal and intrathoracic fat volumes when compared with those without MS [126 ± 33.5 vs. 106 ± 30.1 cm(3) (P < 0.01) and 165 ± 54.9 vs. 140 ± 52 cm(3) (P < 0.01), respectively]. However, there was no significant difference in pericardial fat, mediastinal fat, intrathoracic fat, or fat ratio between patients with or without myocardial infarction during the follow-up [33.6 ± 22.1 vs. 35.7 ± 23.8 cm(3) (P = 0.67); 115 ± 26.2 vs. 114 ± 33.8 cm(3) (P = 0.84); 149 ± 44.7 vs. 150 ± 55.7 cm(3) (P = 0.95); and 0.27 ± 0.15 vs. 0.28 ± 0.14 (P = 0.70), respectively]. There was no significant difference in pericardial fat, mediastinal fat, intrathoracic fat, or fat ratio between patients who were alive compared with those who died during follow-up [36.6 ± 26.6 vs. 35.3 ± 23.2 cm(3) (P = 0.76); 114 ± 40.2 vs. 114 ± 31.4 cm(3) (P = 0.95); 150 ± 64.7 vs. 149 ± 52.5 cm(3) (P = 0.92); and 0.29 ± 0.15 vs. 0.28 ± 0.14 (P = 0.85), respectively].

CONCLUSION

Our study confirms an association between pericardial fat volume with the presence and severity of CAD. Furthermore, an association between mediastinal and intrathoracic fat volumes with MS was found.