Monocytic microRNAs-Novel targets in atherosclerosis therapy.

Atherosclerosis is a chronic proinflammatory disease of the vascular wall resulting in narrowing of arteries due to plaque formation, thereby causing reduced blood supply that is the leading cause for diverse end-organ damage with high mortality rates. Monocytes/macrophages, activated by elevated circulating lipoproteins, are significantly involved in the formation and development of atherosclerotic plaques. The imbalance between proinflammatory and anti-inflammatory macrophages, arising from dysregulated macrophage polarization, appears to be a driving force in this process.

Mitochondria Isolated from Hearts Subjected to Ischemia/Reperfusion Benefit from Adenine Nucleotide Translocase 1 Overexpression.

Reperfusion is the only feasible therapy following myocardial infarction, but reperfusion has been shown to damage mitochondrial function and disrupt energy production in the heart. Adenine nucleotide translocase 1 (ANT1) facilitates the transfer of ADP/ATP across the inner mitochondrial membrane; therefore, we tested whether ANT1 exerts protective effects on mitochondrial function during ischemia/reperfusion (I/R). The hearts of wild-type (WT) and transgenic ANT1-overexpressing (ANT1-TG) rats were exposed to I/R injury using the standard Langendorff technique, after which mitochondrial function, hemodynamic parameters, infarct size, and components of the contractile apparatus were determined.

PI3K as Mediator of Apoptosis and Contractile Dysfunction in TGFβ-Stimulated Cardiomyocytes.

Background: TGFβ is a growth factor that plays a major role in the remodeling process of the heart by inducing cardiomyocyte dysfunction and apoptosis, as well as fibrosis thereby restricting heart function. TGFβ mediates its effect via the TGFβ receptor I (ALK5) and the activation of SMAD transcription factors, but TGFβ is also known as activator of phosphoinositide-3-kinase (PI3K) via the non-SMAD signaling pathway. The aim of this study was to investigate whether PI3K is also involved in TGFβ-induced cardiomyocytes apoptosis and contractile dysfunction.

JDP2, a Novel Molecular Key in Heart Failure and Atrial Fibrillation?

Heart failure (HF) and atrial fibrillation (AF) are two major life-threatening diseases worldwide. Causes and mechanisms are incompletely understood, yet current therapies are unable to stop disease progression. In this review, we focus on the contribution of the transcriptional modulator, Jun dimerization protein 2 (JDP2), and on HF and AF development.

Vascular and Cardiac Oxidative Stress and Inflammation as Targets for Cardioprotection.

Cardiac and vascular diseases are often associated with increased oxidative stress and inflammation, and both may contribute to the disease progression. However, successful applications of antioxidants in the clinical setting are very rare and specific anti-inflammatory therapeutics only emerged recently. Reasons for this rely on the great diversity of oxidative stress and inflammatory cells that can either act as cardioprotective or cause tissue damage in the heart.

Incidence of Atrial Fibrillation in Postmenopausal Women with Endometrial Cancer.

Endometrial cancer (EC) has been associated with an increased risk of cardiovascular disease, including atrial fibrillation (AF). We performed a prospective, case-controlled analysis among 310 Bulgarian women with new-onset, histologically confirmed EC, free of AF at the baseline survey, and women with normal (senile) endometrium/endometrial hyperplasia as a control group ( = 205). The risk of AF as well as relationship of adiponectin (APN) and high sensitivity C-reactive protein (hs-CRP) levels with AF in women with EC were calculated by Cox proportional hazards models.

Matrix Metalloproteinases Repress Hypertrophic Growth in Cardiac Myocytes.

Purpose: Matrix metalloproteinases (MMPs) are identified as modulators of the extracellular matrix in heart failure progression. However, evidence for intracellular effects of MMPs is emerging. Pro- and anti-hypertrophic cardiac effects are described.

Structural, Pro-Inflammatory and Calcium Handling Remodeling Underlies Spontaneous Onset of Paroxysmal Atrial Fibrillation in JDP2-Overexpressing Mice.

Background: Cardiac-specific JDP2 overexpression provokes ventricular dysfunction and atrial dilatation in mice. We performed in vivo studies on JDP2-overexpressing mice to investigate the impact of JDP2 on the predisposition to spontaneous atrial fibrillation (AF).

Methods: JDP2-overexpression was started by withdrawal of a doxycycline diet in 4-week-old mice.

Factor VII Activating Protease Expression in Human Platelets and Accumulation in Symptomatic Carotid Plaque.

Background Factor VII activating protease (FSAP) is of interest as a marker for vascular inflammation and plaque destabilization. The aim of this study was to analyze the expression profile of FSAP in endarterectomy specimens that were taken from patients with asymptomatic and symptomatic carotid atherosclerotic plaques and to compare them with circulating FSAP levels. Methods and Results Plasma FSAP concentration, activity, and mRNA expression were measured in endarterectomy specimens and in monocytes and platelets.

MicroRNA expression profile of human advanced coronary atherosclerotic plaques.

MicroRNA (miR) is reported to be involved in vascular inflammation and may represent a novel class of diagnostic biomarkers in cardiovascular disease. We aimed to identify the miR expression profile in human advanced coronary atherosclerotic plaques (CAP) and to connect this expression to the processes in atherosclerosis. Microarray techniques and TaqMan polymerase chain reaction were used to analyse the global expression of 352 miRs in CAP obtained during ACS MULTI-LINK study.

JDP2 overexpression provokes cardiac dysfunction in mice.

The transcriptional regulator JDP2 (Jun dimerization protein 2) has been identified as a prognostic marker for patients to develop heart failure after myocardial infarction. We now performed in vivo studies on JDP2-overexpressing mice, to clarify the impact of JDP2 on heart failure progression. Therefore, during birth up to the age of 4 weeks cardiac-specific JDP2 overexpression was prevented by doxycycline feeding in transgenic mice.

Publisher Correction: Identification of microRNAs as potential cellular monocytic biomarkers in the early phase of myocardial infarction: a pilot study.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Identification of microRNAs as potential cellular monocytic biomarkers in the early phase of myocardial infarction: a pilot study.

MicroRNA has been increasingly suggested to be involved in vascular inflammation. The aim of this study was to assess the expression profile of miRs as possible novel cellular biomarkers in circulating monocytes in patients with ST-segment elevation myocardial infarction (STEMI). Microarray techniques and TaqMan polymerase chain reaction were used to analyse the global expression of 352 miRNAs in peripheral blood monocytes from healthy donors (n = 20) and patients (n = 24) with acute STEMI.

Endothelial Mesenchymal Transition in Hypoxic Microvascular Endothelial Cells and Paracrine Induction of Cardiomyocyte Apoptosis Are Mediated via TGFβ₁/SMAD Signaling.

Cardiac remodeling plays a crucial role in the development of heart failure after mycocardial infarction. Besides cardiomyocytes, endothelial cells are recognized to contribute to cardiac remodeling. We now investigated processes of endothelial mesenchymal transition (EndoMT) in microvascular endothelial cells of rat (MVEC) under hypoxia and paracrine effects on ventricular cardiomyocytes of adult rat.

Good and bad sides of TGFβ-signaling in myocardial infarction.

Myocardial infarction is a prevailing cause of death in industrial countries. In spite of the good opportunities we have nowadays in interventional cardiology to reopen the clotted coronary arteries for reperfusion of ischemic areas, post-infarct remodeling emerges and contributes to unfavorable structural conversion processes in the myocardium, finally resulting in heart failure. The growth factor TGFβ is upregulated during these processes.

Inhibition of AP-1 signaling by JDP2 overexpression protects cardiomyocytes against hypertrophy and apoptosis induction.

Aims: Expression and activity of the transcription factor AP-1 are enhanced during cardiac remodelling and heart failure progression. In order to test if AP-1 inhibition may limit processes contributing to cardiac remodelling, ventricular cardiomyocytes of mice with cardiac overexpression of the AP-1 inhibitor JDP2 were analysed under stimulation of hypertrophy, apoptosis, or contractile function.

Methods And Results: Three models of JDP2 overexpressing mice were analysed: JDP2 was overexpressed either life-long, for 7 weeks, or 1 week.

TGFβ receptor activation enhances cardiac apoptosis via SMAD activation and concomitant NO release.

Unlabelled: Transforming growth factor β (TGFβ) expression is induced in the myocardium during transition from compensated hypertrophy to heart failure. In cardiomyocytes, stimulation with TGFβ results in restricted contractile function and enhanced apoptosis. Nitric oxide (NO) also induces apoptosis and influences cardiac function.

Transgenic overexpression of heart-specific adenine nucleotide translocase 1 positively affects contractile function in cardiomyocytes.

Background/aims: The adenine nucleotide translocase (ANT) exchanges ATP and ADP over the inner mitochondrial membrane, supplying the cells with energy. Interestingly, myocardial ANT1 overexpression preserves cardiac structure and function under pathophysiological conditions. To ascertain whether the contractile system is directly affected by increased ANT1 expression, we analyzed cell morphology, contraction and relaxation parameters of ANT1 transgenic (ANT1-TG) cardiomyocytes, myofibrillar protein expression, and Ca(2+) handling in ANT1-TG rat hearts.

Controlling cardiomyocyte length: the role of renin and PPAR-{gamma}.

Aims: Renin and peroxisome proliferator-activated receptor (PPAR-γ) interact directly with cardiomyocytes and influence protein synthesis. We investigated their effects and interaction on the size of cardiomyocytes.

Methods And Results: Effects of renin and PPAR-γ activation were studied in cultured adult rat ventricular cardiomyocytes, transgenic mice with a cardiomyocyte-restricted knockout of PPAR-γ, and transgenic rats overexpressing renin, TGR(mRen2)27.

SMAD-proteins as a molecular switch from hypertrophy to apoptosis induction in adult ventricular cardiomyocytes.

Heart failure development goes along with a transition from hypertrophic growth to apoptosis induction. In adult cardiomyocytes SMAD proteins are only activated under apoptotic, but not under hypertrophic conditions and are increased at the transition to heart failure. Therefore, SMADs could be candidates that turn the balance from hypertrophic growth to apoptosis resulting in heart failure development.

Platelet-derived growth factor BB stimulates vasculogenesis of embryonic stem cell-derived endothelial cells by calcium-mediated generation of reactive oxygen species.

Aims: Platelet-derived growth factor BB (PDGF-BB) has been assigned a critical role in vascular growth and recruitment of perivascular mural cells. The purpose of the present study is to investigate the signalling events underlying the stimulation of vasculogenesis of mouse embryonic stem (ES) cells by PDGF-BB.

Methods And Results: PDGF-BB increased vascular sprouting and branching of capillary-like structures in embryoid bodies as evaluated by computer-assisted analysis of CD31-positive cell structures.

Angiotensin II-dependent loss of cardiac function: mechanisms and pharmacological targets attenuating this effect.

Pharmacological inhibition of components of the renin-angiotensin-system is one of the major therapeutically options to treat patients with heart failure. This study hypothesized that angiotensin II (Ang II) directly depresses contractile function (cell shortening) by activation of transforming growth factor-beta(1) (TGF-beta(1)). Moreover, we hypothesized that an inhibition of glycogen synthase kinase 3-betaGSK will compensate for this depressive effect by increasing SERCA2 expression.