Pretreatment with antiplatelet drugs improves the cardiac function after myocardial infarction without reperfusion in a mouse model

Fibroblasts and platelets: a face-to-face dialogue at the heart of cardiac fibrosis

Myocardial fibrosis is a feature found in most cardiac diseases and a key element contributing to heart failure and its progression. It has therefore become a subject of particular interest in cardiac research. Mechanisms leading to pathological cardiac remodeling and heart failure are diverse, including effects on cardiac fibroblasts, the main players in cardiac extracellular matrix synthesis, but also on cardiomyocytes, immune cells, endothelial cells, and more recently, platelets. Although transforming growth factor-β (TGF-β) is a primary regulator of fibrosis development, the cellular and molecular mechanisms that trigger its activation after cardiac injury remain poorly understood. Different types of anti-TGF-β drugs have been tested for the treatment of cardiac fibrosis and have been associated with side effects. Therefore, a better understanding of these mechanisms is of great clinical relevance and could allow us to identify new therapeutic targets. Interestingly, it has been shown that platelets infiltrate the myocardium at an early stage after cardiac injury, producing large amounts of cytokines and growth factors. These molecules can directly or indirectly regulate cells involved in the fibrotic response, including cardiac fibroblasts and immune cells. In particular, platelets are known to be a major source of TGF-β1. In this review, we have provided an overview of the classical cellular effectors involved in the pathogenesis of cardiac fibrosis, focusing on the emergent role of platelets, while discussing opportunities for novel therapeutic interventions.

Current and Future Insights for Optimizing Antithrombotic Therapy to Reduce the Burden of Cardiovascular Ischemic Events in Patients with Acute Coronary Syndrome

The pharmacological treatment strategies for acute coronary syndrome (ACS) in recent years are constantly evolving to develop more potent antithrombotic agents, as reflected by the introduction of more novel P2Y₁₂ receptor inhibitors and anticoagulants to reduce the ischemic risk among ACS patients. Despite the substantial improvements in the current antithrombotic regimen, a noticeable number of ACS patients continue to experience ischemic events. Providing effective ischemic risk reduction while balancing bleeding risk remains a clinical challenge. This updated review discusses the currently approved and widely used antithrombotic agents and explores newer antithrombotic treatment strategies under development for the initial phase of ACS.

ANalgesic Efficacy and safety of MOrphiNe versus methoxyflurane in patients with acute myocardial infarction: the rationale and design of the ANEMON-SIRIO 3 study: a multicentre, open-label, phase II, randomised clinical trial

INTRODUCTION

The unfavourable influence of morphine on the pharmacokinetics of ticagrelor resulting in weaker and retarded antiplatelet effect in patients with acute coronary syndrome (ACS) has been previously shown. Replacing morphine with methoxyflurane, a potent, non-opioid analgesic agent, that does not weaken or delay the effect of antiplatelet agents may improve the clinical efficacy of treatment of patients with ACS.

METHODS

The ANEMON-SIRIO 3 study was designed as a multicentre, open-label, phase II, randomised clinical trial aimed to test the analgesic efficacy and safety of methoxyflurane in patients with ACS. The study population will comprise patients with ST-elevation myocardial infarction or non-ST-elevation ACS admitted to the study centres with typical chest pain requiring analgesic treatment. Before percutaneous coronary intervention (PCI) for the patients with index ACS will be randomly assigned in 1:1 ratio to receive methoxyflurane administered by inhalation, or to obtain morphine administered intravenously. Analgesic treatment will be followed by 300 mg loading dose of aspirin and 180 mg loading dose of ticagrelor. Patients will be assessed with regard to pain intensity according to the Numeric Pain Rating Scale at baseline, 3 min after study drug administration and immediately after PCI. Moreover, patients will be actively monitored with regard to the occurrence of side effects of evaluated therapies, as well as adverse events that may be related to insufficient platelet inhibition (no-reflow phenomenon assessed immediately after PCI, administration of GPIIb/IIIa inhibitors during PCI, acute stent thrombosis).

ETHICS AND DISSEMINATION

The study will be conducted in six Polish clinical centres from the beginning of in accordance with the ethical standards of the institutional research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.

TRIAL REGISTRATION DETAILS

ClinicalTrials.gov, NCT04476173.

The role of labile Zn2+ and Zn2+-transporters in the pathophysiology of mitochondria dysfunction in cardiomyocytes

An important energy supplier of cardiomyocytes is mitochondria, similar to other mammalian cells. Studies have demonstrated that any defect in the normal processes controlled by mitochondria can lead to abnormal ROS production, thereby high oxidative stress as well as lack of ATP. Taken into consideration, the relationship between mitochondrial dysfunction and overproduction of ROS as well as the relation between increased ROS and high-level release of intracellular labile Zn²⁺, those bring into consideration the importance of the events related with those stimuli in cardiomyocytes responsible from cellular Zn²⁺-homeostasis and responsible Zn²⁺-transporters associated with the Zn²⁺-homeostasis and Zn²⁺-signaling. Zn²⁺-signaling, controlled by cellular Zn²⁺-homeostatic mechanisms, is regulated with intracellular labile Zn²⁺ levels, which are controlled, especially, with the two Zn²⁺-transporter families; ZIPs and ZnTs. Our experimental studies in mammalian cardiomyocytes and human heart tissue showed that Zn²⁺-transporters localizes to mitochondria besides sarco(endo)plasmic reticulum and Golgi under physiological condition. The protein levels as well as functions of those transporters can re-distribute under pathological conditions, therefore, they can interplay among organelles in cardiomyocytes to adjust a proper intracellular labile Zn²⁺ level. In the present review, we aimed to summarize the already known Zn²⁺-transporters localize to mitochondria and function to stabilize not only the cellular Zn²⁺ level but also cellular oxidative stress status. In conclusion, one can propose that a detailed understanding of cellular Zn²⁺-homeostasis and Zn²⁺-signaling through mitochondria may emphasize the importance of new mitochondria-targeting agents for prevention and/or therapy of cardiovascular dysfunction in humans.