Plasma Catestatin in Patients with Acute Coronary Syndrome

Electrophysiological Mechanism of Catestatin Antiarrhythmia: Enhancement of Ito, IK, and IK1 and Inhibition of ICa-L in Rat Ventricular Myocytes

BACKGROUND

Cardiovascular disease remains one of the leading causes of death globally. Myocardial ischemia and infarction, in particular, frequently cause disturbances in cardiac electrical activity that can trigger ventricular arrhythmias. We aimed to investigate whether catestatin, an endogenous catecholamine-inhibiting peptide, ameliorates myocardial ischemia-induced ventricular arrhythmias in rats and the underlying ionic mechanisms.

METHODS AND RESULTS

Adult male Sprague-Dawley rats were randomly divided into control and catestatin groups. Ventricular arrhythmias were induced by ligation of the left anterior descending coronary artery and electrical stimulation. Action potential, transient outward potassium current, delayed rectifier potassium current, inward rectifying potassium current, and L-type calcium current (ICa-L) of rat ventricular myocytes were recorded using a patch-clamp technique. Catestatin notably reduced ventricular arrhythmia caused by myocardial ischemia/reperfusion and electrical stimulation of rats. In ventricular myocytes, catestatin markedly shortened the action potential duration of ventricular myocytes, which was counteracted by potassium channel antagonists TEACl and 4-AP, and ICa-L current channel agonist Bay K8644. In addition, catestatin significantly increased transient outward potassium current, delayed rectifier potassium current, and inward rectifying potassium current density in a concentration-dependent manner. Catestatin accelerated the activation and decelerated the inactivation of the transient outward potassium current channel. Furthermore, catestatin decreased ICa-L current density in a concentration-dependent manner. Catestatin also accelerated the inactivation of the ICa-L channel and slowed down the recovery of ICa-L from inactivation.

CONCLUSIONS

Catestatin enhances the activity of transient outward potassium current, delayed rectifier potassium current, and inward rectifying potassium current, while suppressing the ICa-L in ventricular myocytes, leading to shortened action potential duration and ultimately reducing the ventricular arrhythmia in rats.

Plasma catestatin levels are related to metabolic parameters in patients with essential hypertension and type 2 diabetes mellitus

Catestatin (CST) is a pleiotropic peptide with cardioprotective and metabolic effects. CST is involved in the pathogenesis of both arterial hypertension (AH) and type 2 diabetes mellitus (T2DM), which are the risk factors of cardiovascular diseases. In this study, we aimed to investigate the plasma CST levels in hypertensive patients, especially with T2DM, as well as compare those with healthy volunteers, and explore the relationship between CST levels and clinical, anthropometric and laboratory parameters. 106 Hypertensive patients, 55 of which had comorbidity T2DM, and 30 healthy volunteers were enrolled in the study. All subjects underwent clinical examination, including vital signs and anthropometric data assessment, medical history interview, and blood sample collection. Plasma CST levels were measured by an enzyme-linked immunosorbent assay (ELISA), using a commercial diagnostic kit. The plasma CST levels were significantly lower in hypertensive patients (N = 106) compared with healthy subjects (N = 30) (5.02 ± 1.09 vs. 6.64 ± 0.72; p < 0.001). Furthermore, hypertensive patients with T2DM (N = 55) have significantly reduced CST levels in comparison with those without T2DM (N = 51) (4.47 ± 1.16 vs. 5.61 ± 0.61; p < 0.001). CST significantly correlated with anthropometric characteristics, in particular, weight (r =  - 0.344; p < 0.001), BMI (r =  - 0.42; p < 0.001), neck (r =  - 0.358; p < 0.001), waist (r =  - 0.487; p < 0.001), hip (r =  - 0.312; p < 0.001), wrist circumferences (r =  - 0.264; p = 0.002), and waist-to-hip ratio (r =  - 0.395; p < 0.001). Due to its antihypertensive effect, CST has significant associations with systolic BP (r =  - 0.475; p < 0.001) and duration of AH (r =  - 0.26; p = 0.007). CST also has an inverse relationship with insulin (r =  - 0.382; p < 0.001), glucose (r =  - 0.45; p < 0.001), index HOMA-IR (r =  - 0.481; p < 0.001) and HbA1c (r =  - 0.525; p < 0.001), that indicate its involvement in T2DM development. Besides, CST has significant correlations with uric acid levels (r =  - 0.412; p < 0.001) as well as lipid parameters, especially HDL-C (r = 0.480; p < 0.001), VLDL-C (r =  - 0.238; p = 0.005), TG (r =  - 0.4; p < 0.001), non-HDL-C/HDL-C (r =  - 0.499; p < 0.001). Multiple linear regression analysis indicated BMI (β =  - 0.22; p = 0.007), AH duration (β =  - 0.25; p = 0.008), HbA1c (β =  - 0.43; p = 0.019) and HDL-C levels (β = 0.27; p = 0.001) as independent predictors of CST levels. The hypertensive patients have significantly decreased CST levels that are even more reduced in the presence of comorbid T2DM. The established correlations with anthropometric and laboratory parameters indicate not only antihypertensive but also metabolic effects of CST. Our results suggest the probable role of CST in the pathophysiology of cardiometabolic diseases and the development of cardiovascular complications.

Chromogranin A and its derived peptides: potential regulators of cholesterol homeostasis

Chromogranin A (CHGA), a member of the granin family of proteins, has been an attractive therapeutic target and candidate biomarker for several cardiovascular, neurological, and inflammatory disorders. The prominence of CHGA stems from the pleiotropic roles of several bioactive peptides (e.g., catestatin, pancreastatin, vasostatins) generated by its proteolytic cleavage and by their wide anatomical distribution. These peptides are emerging as novel modulators of cardiometabolic diseases that are often linked to high blood cholesterol levels. However, their impact on cholesterol homeostasis is poorly understood. The dynamic nature of cholesterol and its multitudinous roles in almost every aspect of normal body function makes it an integral component of metabolic physiology. A tightly regulated coordination of cholesterol homeostasis is imperative for proper functioning of cellular and metabolic processes. The deregulation of cholesterol levels can result in several pathophysiological states. Although studies till date suggest regulatory roles for CHGA and its derived peptides on cholesterol levels, the mechanisms by which this is achieved still remain unclear. This review aims to aggregate and consolidate the available evidence linking CHGA with cholesterol homeostasis in health and disease. In addition, we also look at common molecular regulatory factors (viz., transcription factors and microRNAs) which could govern the expression of CHGA and genes involved in cholesterol homeostasis under basal and pathological conditions. In order to gain further insights into the pathways mediating cholesterol regulation by CHGA/its derived peptides, a few prospective signaling pathways are explored, which could act as primers for future studies.

Serum chromogranin A levels are associated with the SYNTAX score in coronary artery disease

OBJECTIVE

In this article, we investigated the association of chromogranin A with coronary artery disease.

METHODS

Biochemical parameters and chromogranin A levels obtained from peripheral blood samples during coronary angiography were analyzed in 90 patients. Patients were classified into two groups, namely, SYNergy between PCI with TAXUS and Cardiac Surgery score ≥1 (n=45) and SYNergy between PCI with TAXUS and Cardiac Surgery score=0 (n=45). This is a cross-sectional, prospective study.

RESULTS

Serum chromogranin A levels were significantly higher in the group with SYNergy between PCI with TAXUS and Cardiac Surgery score ≥1 compared to the group with SYNergy between PCI with TAXUS and Cardiac Surgery score=0 (1381.5±418.9 ng/mL and 1121.2±290.7 ng/mL, respectively; p=0.002). Serum chromogranin A levels were correlated with SYNergy between PCI with TAXUS and Cardiac Surgery score (r=0.556, p<0.04). ROC analysis showed that the area under the curve for serum chromogranin A levels was 0.687 (p=0.007), and the best cutoff value of 1,131 ng/mL had a sensitivity of 67% and a specificity of 65% for the prediction of coronary artery disease.

CONCLUSION

Serum chromogranin A levels were increased in coronary artery disease patients with SYNergy between PCI with TAXUS and Cardiac Surgery score ≥1. Increasing serum chromogranin A levels are proportional to the SYNergy between PCI with TAXUS and Cardiac Surgery score.

Role of Catestatin in the Cardiovascular System and Metabolic Disorders

Catestatin is a multifunctional peptide that is involved in the regulation of the cardiovascular and immune systems as well as metabolic homeostatis. It mitigates detrimental, excessive activity of the sympathetic nervous system by inhibiting catecholamine secretion. Based on in vitro and in vivo studies, catestatin was shown to reduce adipose tissue, inhibit inflammatory response, prevent macrophage-driven atherosclerosis, and regulate cytokine production and release. Clinical studies indicate that catestatin may influence the processes leading to hypertension, affect the course of coronary artery diseases and heart failure. This review presents up-to-date research on catestatin with a particular emphasis on cardiovascular diseases based on a literature search.

The Role of Angiogenesis and Arteriogenesisin Myocardial Infarction and Coronary Revascularization

Surgical myocardial revascularization is associated with long-term survival benefit in patients with multivessel coronary artery disease. However, the exact biological mechanisms underlying the clinical benefits of myocardial revascularization have not been elucidated yet. Angiogenesis and arteriogenesis biologically leading to vascular collateralization are considered one of the endogenous mechanisms to preserve myocardial viability during ischemia, and the presence of coronary collateralization has been regarded as one of the predictors of long-term survival in patients with coronary artery disease (CAD). Some experimental studies and indirect clinical evidence on chronic CAD confirmed an angiogenetic response induced by myocardial revascularization and suggested that revascularization procedures could constitute an angiogenetic trigger per se. In this review, the clinical and basic science evidence regarding arteriogenesis and angiogenesis in both CAD and coronary revascularization is analyzed with the aim to better elucidate their significance in the clinical arena and potential therapeutic use.

Prognostic differences of catestatin among young and elderly patients with acute myocardial infarction

BACKGROUND

Previous studies have reported inconsistent findings regarding the association between catestatin and outcomes of acute myocardial infarction (AMI). This study aims to investigate the prognostic value of catestatin for long-term outcomes in patients with AMI.

METHODS

One hundred and sixty-five patients with AMI were enrolled in this series. The plasma catestatin levels at baseline and clinical data were collected. All patients were followed up for four years to investigate whether there were major adverse cardiovascular events (MACEs), including cardiovascular death, recurrent AMI, rehospitalization for heart failure, and revascularization.

RESULTS

There were 24 patients who had MACEs during the follow-up period. The MACEs group had significantly lower plasma catestatin levels (0.74±0.49 ng/mL vs. 1.10±0.79 ng/mL, P=0.033) and were older (59.0±11.4 years old vs. 53.2±12.8 years old, P=0.036). The rate of MACEs was significantly higher in the elderly group (≥60 years old) than in the young group (<60 years old) (23.8% [15/63] vs. 8.8% [9/102], P=0.008). The catestatin level was significantly lower in the MACEs group than that in the non-MACEs group (0.76±0.50 ng/mL vs. 1.31±0.77 ng/mL, P=0.012), and catestatin was significantly associated with MACEs (Kaplan Meier, P=0.007) among the elderly group, but not in the young group (Kaplan Meier, P=0.893). In the Cox proportional hazards regression, high catestatin was one of the independent factors for predicting MACEs after adjustment for other risk factors (hazard ratio 0.19, 95% confidence interval 0.06-0.62, P=0.006) among elderly patients.

CONCLUSIONS

Elderly AMI patients with lower plasma catestatin levels are more likely to develop MACEs. Catestatin may be a novel marker for the long-term prognosis of AMI, especially in elderly patients.

Associations between chronic work stress and plasma chromogranin A/catestatin among healthy workers

OBJECTIVES

Plasma chromogranin A (CgA) may play a critical role on linking work stress to health outcomes. The aim of our study was to investigate the associations between work stress and plasma CgA levels in healthy workers without chronic diseases.

METHODS

The study included 260 healthy workers from EHOP study. Work stressors were assessed by the Chinese version of the 23-item ERI-Q questionnaire. Plasma CgA and catestatin levels were measured by ELISA kits. The demographic characteristics were collected from medical records.

RESULTS

Among the final 260 subjects including 173 males (66.5%) and 87 females (33.5%), the average age was 37.6 ± 10.6 years old. Effort, overcommitment, and ERI were positively associated with plasma CgA level, respectively (r = 0.267, 0.319, and 0.304, all p < .001), while reward was negatively associated with CgA level (r = -0.237, p < .001). The workers with high effort, overcommitment, or ERI had significantly higher plasma CgA levels, while the workers with high rewards had significantly lower plasma CgA levels. The workers with both high overcommitment and high ERI had highest plasma CgA levels. In the linear regression analysis, after adjustment for confounders, effort, overcommitment, and ERI were respectively positively related to plasma CgA, while reward negatively related to plasma CgA. The associations between work stress and plasma catestatin was not significant. The ratio of CgA and catestatin was associated with work stress.

CONCLUSIONS

Work stress is associated with plasma CgA which may be play a crucial role on the pathway from chronic work stress to cardiovascular diseases.

The Emerging Roles of Chromogranins and Derived Polypeptides in Atherosclerosis, Diabetes, and Coronary Heart Disease

Chromogranin A (CgA), B (CgB), and C (CgC), the family members of the granin glycoproteins, are associated with diabetes. These proteins are abundantly expressed in neurons, endocrine, and neuroendocrine cells. They are also present in other areas of the body. Patients with diabetic retinopathy have higher levels of CgA, CgB, and CgC in the vitreous humor. In addition, type 1 diabetic patients have high CgA and low CgB levels in the circulating blood. Plasma CgA levels are increased in patients with hypertension, coronary heart disease, and heart failure. CgA is the precursor to several functional peptides, including catestatin, vasostatin-1, vasostatin-2, pancreastatin, chromofungin, and many others. Catestatin, vasostain-1, and vasostatin-2 suppress the expression of vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 in human vascular endothelial cells. Catestatin and vasostatin-1 suppress oxidized low-density lipoprotein-induced foam cell formation in human macrophages. Catestatin and vasostatin-2, but not vasostatin-1, suppress the proliferation and these three peptides suppress the migration in human vascular smooth muscles. Chronic infusion of catestatin, vasostatin-1, or vasostatin-2 suppresses the development of atherosclerosis of the aorta in apolipoprotein E-deficient mice. Catestatin, vasostatin-1, vasostatin-2, and chromofungin protect ischemia/reperfusion-induced myocardial dysfunction in rats. Since pancreastatin inhibits insulin secretion from pancreatic β-cells, and regulates glucose metabolism in liver and adipose tissues, pancreastatin inhibitor peptide-8 (PSTi8) improves insulin resistance and glucose homeostasis. Catestatin stimulates therapeutic angiogenesis in the mouse hind limb ischemia model. Gene therapy with secretoneurin, a CgC-derived peptide, stimulates postischemic neovascularization in apolipoprotein E-deficient mice and streptozotocin-induced diabetic mice, and improves diabetic neuropathy in db/db mice. Therefore, CgA is a biomarker for atherosclerosis, diabetes, hypertension, and coronary heart disease. CgA- and CgC--derived polypeptides provide the therapeutic target for atherosclerosis and ischemia-induced tissue damages. PSTi8 is useful in the treatment of diabetes.

Plasma Catestatin Levels and Advanced Glycation End Products in Patients on Hemodialysis

Catestatin (CST) is a pleiotropic peptide involved in cardiovascular protection with its antihypertensive and angiogenic effects. Considering that patients with end-stage renal disease (ESRD) who are undergoing hemodialysis (HD) are associated with higher cardiovascular risk, the aim of this study was to investigate plasma CST levels in HD patients, compare them to healthy controls and evaluate possible CST associations with advanced glycation end products (AGEs) and laboratory, anthropometric and clinical parameters. The study included 91 patients on HD and 70 healthy controls. Plasma CST levels were determined by an enzyme-linked immunosorbent assay in a commercially available diagnostic kit, while AGEs were determined using skin autofluorescence. Plasma CST levels were significantly higher in the HD group compared to the controls (32.85 ± 20.18 vs. 5.39 ± 1.24 ng/mL, p < 0.001) and there was a significant positive correlation between CST and AGEs (r = 0.492, p < 0.001). Furthermore, there was a significant positive correlation between plasma CST levels with both the Dialysis Malnutrition Score (r = 0.295, p = 0.004) and Malnutrition-Inflammation Score (r = 0.290, p = 0.005). These results suggest that CST could be playing a role in the complex pathophysiology of ESRD/HD and that it could affect the higher cardiovascular risk of patients on HD.

Decreased circulating catestatin levels are associated with coronary artery disease: The emerging anti-inflammatory role

BACKGROUND AND AIMS

The neuropeptide catestatin (CST) is an endogenous nicotinic cholinergic antagonist that acts as pleiotropic cardiac protective hormone. This study investigated the association between CST and coronary artery disease (CAD) and the underlying mechanisms.

METHODS AND RESULTS

The serum concentration of CST among 224 CAD patients and 204 healthy controls was compared, and its association with atherosclerosis severity in 921 CAD patients was further analyzed. Compared to healthy subjects, serum CST concentration was lower in patients with CAD [1.14 (1.05-1.24) ng/mL vs. 2.15 (1.92-2.39) ng/mL, p < 0.001] and was inversely correlated with disease severity (r = -0.208, p < 0.001). In cultured endothelial cells, CST suppressed TNF-α-elicited expression of inflammatory cytokines and adhesion molecules by activating angiotensin-converting enzyme-2 (ACE2). Administration of CST reduced leukocyte-endothelium interactions in vitro and in vivo, and attenuated the development of atherosclerotic in ApoE^-/- mice fed a high-fat diet. These protective effects by CST were blocked by an ACE2 inhibitor.

CONCLUSIONS

Serum CST concentration is lower in CAD patients and is inversely associated with the severity of atherosclerosis. CST acts as a novel anti-atherogenic peptide that inhibits inflammatory response and EC-leukocyte interactions via an ACE2-dependent mechanism.

Catestatin Induces Glucose Uptake and GLUT4 Trafficking in Adult Rat Cardiomyocytes

Catestatin is a cationic and hydrophobic peptide derived from the enzymatic cleavage of the prohormone Chromogranin A. Initially identified as a potent endogenous nicotinic-cholinergic antagonist, Catestatin has recently been shown to act as a novel regulator of cardiac function and blood pressure and as a cardioprotective agent in both pre- and postconditioning through AKT-dependent mechanisms. The aim of this study is to investigate the potential role of Catestatin also on cardiac metabolism modulation, particularly on cardiomyocytes glucose uptake. Experiments were performed on isolated adult rat cardiomyocytes. Glucose uptake was assessed by fluorescent glucose incubation and confocal microscope analysis. Glut4 plasma membrane translocation was studied by immunofluorescence experiments and evaluation of the ratio peripheral vs internal Glut4 staining. Furthermore, we performed immunoblot experiments to investigate the involvement of the intracellular pathway AKT/AS160 in the Catestatin dependent Glut4 trafficking. Our results show that 10 nM Catestatin induces a significant increase in the fluorescent glucose uptake, comparable to that exerted by 100 nM Insulin. Moreover, Catestatin stimulates Glut4 translocation to plasma membrane and both AKT and AS160 phosphorylation. All these effects were inhibited by Wortmannin. On the whole, we show for the first time that Catestatin is able to modulate cardiac glucose metabolism, by inducing an increase in glucose uptake through Glut4 translocation to the plasma membrane and that this mechanism is mediated by the AKT/AS160 intracellular pathway.

Circulating chromogranin A and its fragments as diagnostic and prognostic disease markers

Chromogranin A (CgA), a secretory protein released in the blood by neuroendocrine cells and neurons, is the precursor of various bioactive fragments involved in the regulation of the cardiovascular system, metabolism, innate immunity, angiogenesis, and tissue repair. After the original demonstration that circulating CgA can serve as a biomarker for a wide range of neuroendocrine tumors, several studies have shown that increased levels of CgA can be present also in the blood of patients with cardiovascular, gastrointestinal, and inflammatory diseases with, in certain cases, important diagnostic and prognostic implications. Considering the high structural and functional heterogeneity of the CgA system, comprising precursor and fragments, it is not surprising that the different immunoassays used in these studies led, in some cases, to discrepant results. Here, we review these notions and we discuss the importance of measuring total-CgA, full-length CgA, specific fragments, and their relative levels for a more thorough assessment of the pathophysiological function and diagnostic/prognostic value of the CgA system.

The role of neuropeptides in adverse myocardial remodeling and heart failure

In addition to traditional neurotransmitters of the sympathetic and parasympathetic nervous systems, the heart also contains numerous neuropeptides. These neuropeptides not only modulate the effects of neurotransmitters, but also have independent effects on cardiac function. While in most cases the physiological actions of these neuropeptides are well defined, their contributions to cardiac pathology are less appreciated. Some neuropeptides are cardioprotective, some promote adverse cardiac remodeling and heart failure, and in the case of others their functions are unclear. Some have both cardioprotective and adverse effects depending on the specific cardiac pathology and progression of that pathology. In this review, we briefly describe the actions of several neuropeptides on normal cardiac physiology, before describing in more detail their role in adverse cardiac remodeling and heart failure. It is our goal to bring more focus toward understanding the contribution of neuropeptides to the pathogenesis of heart failure, and to consider them as potential therapeutic targets.