Nanoparticle-Mediated Simultaneous Targeting of Mitochondrial Injury and Inflammation Attenuates Myocardial Ischemia-Reperfusion Injury

Multiple delivery strategies of nanocarriers for myocardial ischemia-reperfusion injury: current strategies and future prospective

Acute myocardial infarction, characterized by high morbidity and mortality, has now become a serious health hazard for human beings. Conventional surgical interventions to restore blood flow can rapidly relieve acute myocardial ischemia, but the ensuing myocardial ischemia-reperfusion injury (MI/RI) and subsequent heart failure have become medical challenges that researchers have been trying to overcome. The pathogenesis of MI/RI involves several mechanisms, including overproduction of reactive oxygen species, abnormal mitochondrial function, calcium overload, and other factors that induce cell death and inflammatory responses. These mechanisms have led to the exploration of antioxidant and inflammation-modulating therapies, as well as the development of myocardial protective factors and stem cell therapies. However, the short half-life, low bioavailability, and lack of targeting of these drugs that modulate these pathological mechanisms, combined with liver and spleen sequestration and continuous washout of blood flow from myocardial sites, severely compromise the expected efficacy of clinical drugs. To address these issues, employing conventional nanocarriers and integrating them with contemporary biomimetic nanocarriers, which rely on passive targeting and active targeting through precise modifications, can effectively prolong the duration of therapeutic agents within the body, enhance their bioavailability, and augment their retention at the injured myocardium. Consequently, these approaches significantly enhance therapeutic effectiveness while minimizing toxic side effects. This article reviews current drug delivery systems used for MI/RI, aiming to offer a fresh perspective on treating this disease.

Advanced Nanomedicine Approaches for Myocardial Infarction Treatment

Myocardial infarction, usually caused by the rupture of atherosclerotic plaque, leads to irreversible ischemic cardiomyocyte death within hours followed by impaired cardiac performance or even heart failure. Current interventional reperfusion strategies for myocardial infarction still face high mortality with the development of heart failure. Nanomaterial-based therapy has made great progress in reducing infarct size and promoting cardiac repair after MI, although most studies are preclinical trials. This review focuses primarily on recent progress (2016-now) in the development of various nanomedicines in the treatment of myocardial infarction. We summarize these applications with the strategy of mechanism including anti-cardiomyocyte death strategy, activation of neovascularization, antioxidants strategy, immunomodulation, anti-cardiac remodeling, and cardiac repair.

Cyclophilin D induces necrotic core formation by mediating mitochondria-associated macrophage death in advanced atherosclerotic lesions

BACKGROUND AND AIMS

In advanced atherosclerotic lesions, macrophage deaths result in necrotic core formation and plaque vulnerability. Cyclophilin D (CypD) is a mitochondria-specific cyclophilin involved in the process of cell death after organ ischemia-reperfusion. However, the role of CypD in atherosclerosis, especially in necrotic core formation, is unknown. Therefore, this experiment aims to clarify the role of CypD in necrotic core formation.

METHODS

To clarify the specific role of CypD, encoded by Ppif in mice, apolipoprotein-E/CypD-double knockout (Apoe-/-Ppif-/-) mice were generated. These mice were fed a high-fat diet containing 0.15 % cholesterol for 24 weeks to accelerate atherosclerotic lesion development.

RESULTS

Deletion of CypD decreased the necrotic core size, accompanied by a reduction of macrophage apoptosis compared to control Apoe-/- mice. In RAW264.7 cells, siRNA-mediated knockdown of CypD attenuated the release of cytochrome c from the mitochondria to the cytosol induced by endoplasmic reticulum stress inducer thapsigargin. In addition, necroptosis, induced by TNF-α and caspase inhibitor, was attenuated by knockdown of CypD. Ly-6Chigh inflammatory monocytes in peripheral blood leukocytes and mRNA expression of Il1b in the aorta were decreased by deletion of CypD. In contrast, siRNA-mediated knockdown of CypD did not significantly decrease Il1b nor Ccl2 mRNA expression in RAW264.7 cells treated with LPS and IFN-γ, suggesting that inhibition of inflammation in vivo is likely due to decreased cell death in the atherosclerotic lesions rather than a direct action of CypD deletion on the macrophage.

CONCLUSIONS

These results indicate that CypD induces macrophage death and mediates necrotic core formation in advanced atherosclerotic lesions. CypD could be a novel therapeutic target for treating atherosclerotic vascular diseases.

Nanoparticle-based therapeutic strategies for mitochondrial dysfunction in cardiovascular disease

Although cardiovascular diseases (CVD) are the leading cause of global mortality, there is a lack of therapies that target and revert underlying pathological processes. Mitochondrial dysfunction is involved in the pathophysiology of CVD, and thus is a potential target for therapeutic development. To target the mitochondria and improve therapeutic efficacy, nanoparticle-based delivery systems have been proposed as promising strategies for the delivery of therapeutic agents to the mitochondria. This review will first discuss how mitochondrial dysfunction is related to the progression of several CVD and then delineate recent progress in mitochondrial targeting using nanoparticle-based delivery systems including peptide-based nanosystems, polymeric nanoparticles, liposomes, and lipid nanoparticles. In addition, we summarize the advantages of these nanocarriers and remaining challenges in targeting the mitochondria as a therapeutic strategy for CVD treatment.

Advances in Nanoparticles in the Prevention and Treatment of Myocardial Infarction

Myocardial infarction (MI) is one of the most prevalent types of cardiovascular disease. During MI, myocardial cells become ischemic and necrotic due to inadequate blood perfusion, leading to irreversible damage to the heart. Despite the development of therapeutic strategies for the prevention and treatment of MI, their effects are still unsatisfactory. Nanoparticles represent a new strategy for the pre-treatment and treatment of MI, and novel multifunctional nanoparticles with preventive and therapeutic capabilities hold promise for the prevention and treatment of this disease. This review summarizes the common types and properties of nanoparticles, and focuses on the research progress of nanoparticles for the prevention and treatment of MI.

IL-1 signaling pathway, an important target for inflammation surrounding in myocardial infarction

Acute myocardial infarction is an important cardiovascular disease worldwide. Although the mortality rate of myocardial infarction (MI) has improved dramatically in recent years due to timely treatment, adverse remodeling of the left ventricle continues to affect cardiac function. Various immune cells are involved in this process to induce inflammation and amplification. The infiltration of inflammatory cells in the infarcted myocardium is induced by various cytokines and chemokines, and the recruitment of leukocytes further amplifies the inflammatory response. As an increasing number of clinical anti-inflammatory therapies have achieved significant success in recent years, treating myocardial infarction by targeting inflammation may become a novel therapeutic option. In particular, successful clinical trials of canakinumab have demonstrated the important role of the inflammatory factor interleukin-1 (IL-1) in atherosclerosis. Targeted IL-1 therapy may decrease inflammation levels and improve cardiac function in patients after myocardial infarction. This article reviews the complex series of responses after myocardial infarction, including the involvement of inflammatory cells and the role of cytokines and chemokines, focusing on the progression of the IL-1 family in myocardial infarction as well as the performance of current targeted therapy drugs in experiments.

Emerging Therapeutic Strategies in Sarcopenia: An Updated Review on Pathogenesis and Treatment Advances

Sarcopenia is a prevalent degenerative skeletal muscle condition in the elderly population, posing a tremendous burden on diseased individuals and healthcare systems worldwide. Conventionally, sarcopenia is currently managed through nutritional interventions, physical therapy, and lifestyle modification, with no pharmaceutical agents being approved for specific use in this disease. As the pathogenesis of sarcopenia is still poorly understood and there is no treatment recognized as universally effective, recent research efforts have been directed at better comprehending this illness and diversifying treatment strategies. In this respect, this paper overviews the new advances in sarcopenia treatment in correlation with its underlying mechanisms. Specifically, this review creates an updated framework for sarcopenia, describing its etiology, pathogenesis, risk factors, and conventional treatments, further discussing emerging therapeutic approaches like new drug formulations, drug delivery systems, stem cell therapies, and tissue-engineered scaffolds in more detail.

A bibliography of smart nanomaterials biological application in myocardial infarction research

Myocardial infarction has been considered the top cause of mortality globally. Numerous studies investigated the biological application of smart nanomaterials in myocardial infarction. Our study aimed to provide an overview of this area through bibliography research. Literature related to the biological application of nanomaterials was retrieved from the web of science core collection database. Bibliography analysis was performed using Microsoft Excel, VOSviewer, Citespace, and the R package "bibliometrix." A total of 1226 publications were included. The USA, China, and India carried out the most of studies. Harvard University is the most productive institution. Matthias Nahrendorf ranked first in article volume and also owned the highest impact. Keyword burst analysis indicated the frontiers and hotspots to be gold nanoparticles and iron oxide nanoparticles. This bibliography analysis provides a comprehensive overview of uncovered current research trends and emerging hotspots of nanomaterials' biological application in myocardial infarction, thus inspiring further investigations.

Improved cardioprotective effect of 3-nitro-N-methyl salicylamide solution after a prolonged preservation time of rat heart

Ischemic reperfusion injury, caused by oxidative stress during reperfusion, is an inevitable outcome of organ transplantation, especially when the organ preservation time is prolonged. Prolonged ischaemic preservation is a valuable technique for improving the success of organ transplantation, but numerous challenges remain. 3-nitro-N-methyl salicylamide (3-NNMS), an inhibitor of mitochondrial electron transport chain complex III, can be used to reduce reactive oxygen species production during blood reperfusion by slowing the electron flow rate of the respiratory chain. Based on this property, a novel preservation solution was developed for the preservation of isolated rat heart and its cardioprotective effect was investigated during an 8-h cold ischaemia preservation time for the first time. For comparison, 3-NNMS was also included in the histidine-tryptophan-ketoglutarate (HTK) solution. Compared to HTK, HTK supplemented with 3-NNMS significantly improved the heart rate of isolated rat hearts after 8 h of cold storage. Both 3-NNMS solution and HTK supplemented with 3-NNMS solution decreased cardiac troponin T and lactate dehydrogenase levels in perfusion fluid and reduced reactive oxygen species and malondialdehyde levels in the myocardium. The 3-NNMS also maintained the membrane potential of myocardial mitochondria and significantly increased superoxide dismutase levels. These results showed that the new 3-NNMS solution can protect mitochondrial and cardiomyocyte function by increasing antioxidant capacity and reducing oxidative stress in cryopreserved rat hearts during a prolonged preservation time, resulting in less myocardial injury and better heart rate.

Biomaterials-mediated targeted therapeutics of myocardial ischemia-reperfusion injury

Reperfusion therapy is widely used to treat acute myocardial infarction. However, its efficacy is limited by myocardial ischemia-reperfusion injury (MIRI), which occurs paradoxically due to the reperfusion therapy and contributes to the high mortality rate of acute myocardial infarction. Systemic administration of drugs, such as antioxidant and anti-inflammatory agents, to reduce MIRI is often ineffective due to the inadequate release at the pathological sites. Functional biomaterials are being developed to optimize the use of drugs by improving their targetability and bioavailability and reducing side effects, such as gastrointestinal irritation, thrombocytopenia, and liver damage. This review provides an overview of controlled drug delivery biomaterials for treating MIRI by triggering antioxidation, calcium ion overload inhibition, and/or inflammation regulation mechanisms and discusses the challenges and potential applications of these treatments clinically.

Nanotechnology in coronary heart disease

Coronary heart disease (CHD) is one of the major causes of death and disability worldwide, especially in low- and middle-income countries and among older populations. Conventional diagnostic and therapeutic approaches have limitations such as low sensitivity, high cost and side effects. Nanotechnology offers promising alternative strategies for the diagnosis and treatment of CHD by exploiting the unique properties of nanomaterials. In this review, we use bibliometric analysis to identify research hotspots in the application of nanotechnology in CHD and provide a comprehensive overview of the current state of the art. Nanomaterials with enhanced imaging and biosensing capabilities can improve the early detection of CHD through advanced contrast agents and high-resolution imaging techniques. Moreover, nanomaterials can facilitate targeted drug delivery, tissue engineering and modulation of inflammation and oxidative stress, thus addressing multiple aspects of CHD pathophysiology. We discuss the application of nanotechnology in CHD diagnosis (imaging and sensors) and treatment (regulation of macrophages, cardiac repair, anti-oxidative stress), and provide insights into future research directions and clinical translation. This review serves as a valuable resource for researchers and clinicians seeking to harness the potential of nanotechnology in the management of CHD. STATEMENT OF SIGNIFICANCE: Coronary heart disease (CHD) is the one of leading cause of death and disability worldwide. Nanotechnology offers new strategies for diagnosing and treating CHD by exploiting the unique properties of nanomaterials. This review uses bibliometric analysis to uncover research trends in the use of nanotechnology for CHD. We discuss the potential of nanomaterials for early CHD detection through advanced imaging and biosensing, targeted drug delivery, tissue engineering, and modulation of inflammation and oxidative stress. We also offer insights into future research directions and potential clinical applications. This work aims to guide researchers and clinicians in leveraging nanotechnology to improve CHD patient outcomes and quality of life.

Current Advances of Mitochondrial Dysfunction and Cardiovascular Disease and Promising Therapeutic Strategies

Mitochondria are cellular power stations and essential organelles for maintaining cellular homeostasis. Dysfunctional mitochondria have emerged as a key factor in the occurrence and development of cardiovascular disease. This review focuses on advances in the relationship between mitochondrial dysfunction and cardiovascular diseases such as atherosclerosis, heart failure, myocardial ischemia reperfusion injury, and pulmonary arterial hypertension. The clinical value and challenges of mitochondria-targeted strategies, including mitochondria-targeted antioxidants, mitochondrial quality control modulators, mitochondrial function protectors, mitochondrial biogenesis promoters, and recently developed mitochondrial transplants, are also discussed.

Nanotherapeutics for the Myocardium: A Potential Alternative for Treating Cardiac Diseases

ABSTRACT

Cardiovascular diseases (CVDs) are the foremost cause of morbidity and mortality worldwide. Current clinical interventions include invasive approaches for progressed conditions and pharmacological assistance for initial stages, which has systemic side effects. Preventive, curative, diagnostic, and theranostic (therapeutic + diagnostic) approaches till date are not very useful in combating the ongoing CVD epidemic, which demands a promising efficient alternative approach. To combat the growing CVD outbreak globally, the ideal strategy is to make the therapeutic intervention least invasive and direct to the heart to reduce the bystander effects on other organs and increase the bioavailability of the therapeutics to the myocardium. The application of nanoscience and nanoparticle-mediated approaches have gained a lot of momentum because of their efficient passive and active myocardium targeting capability owing to their improved specificity and controlled release. This review provides extensive insight into the various types of nanoparticles available for CVDs, their mechanisms of targeting (eg, direct or indirect), and the utmost need for further development of bench-to-bedside cardiac tissue-based nanomedicines. Furthermore, the review aims to summarize the different ideas and methods of nanoparticle-mediated therapeutic approaches to the myocardium till date with present clinical trials and future perspectives. This review also reflects the potential of such nanoparticle-mediated tissue-targeted therapies to contribute to the sustainable development goals of good health and well-being.

Intravascularly Deliverable Biomaterial Platforms for Tissue Repair and Regeneration Post-Myocardial Infarction

Each year, nearly 19 million people die of cardiovascular disease with coronary heart disease and myocardial infarction (MI) as the leading cause of the progression of heart failure. Due to the high risk associated with surgical procedures, a variety of minimally invasive therapeutics aimed at tissue repair and regeneration are being developed. While biomaterials delivered via intramyocardial injection have shown promise, there are challenges associated with delivery in acute MI. In contrast, intravascularly injectable biomaterials are a desirable category of therapeutics due to their ability to be delivered immediately post-MI via less invasive methods. In addition to passive diffusion into the infarct, these biomaterials can be designed to target the molecular and cellular characteristics seen in MI pathophysiology, such as cells and proteins present in the ischemic myocardium, to reduce off-target localization. These injectable materials can also be stimuli-responsive through enzymes or chemical imbalances. This review outlines the natural and synthetic biomaterial designs that allow for retention and accumulation within the infarct via intravascular delivery, including intracoronary infusion and intravenous injection.

Cardioprotective Effects of Nanoparticles in Cardiovascular Diseases: A State-of-the-Art Review

It has been reported that death related to cardiovascular disease has increased up to 12.5% just in the past decade alone with various factors playing a role. In 2015 alone, it has been estimated that there were 422.7 million cases of CVD with 17.9 million deaths. Various therapies have been discovered to control and treat CVDs and their complications including reperfusion therapies and pharmacological approaches but many patients still progress to heart failure. Due to these proven adverse effects of existing therapies, various novel therapeutic techniques have emerged in the near past. Nano formulation is one of them. It is a practical therapeutic strategy to minimize pharmacological therapy's side effects and nontargeted distribution. Nanomaterials are suitable for treating CVDs due to their small size, which enables them to reach more sites of the heart and arteries. The biological safety, bioavailability, and solubility of the drugs have been increased due to the encapsulation of natural products and their derivatives of drugs.

Perspectives on mitochondrial relevance in cardiac ischemia/reperfusion injury

Cardiovascular disease is the most common cause of death worldwide and in particular, ischemic heart disease holds the most considerable position. Even if it has been deeply studied, myocardial ischemia-reperfusion injury (IRI) is still a side-effect of the clinical treatment for several heart diseases: ischemia process itself leads to temporary damage to heart tissue and obviously the recovery of blood flow is promptly required even if it worsens the ischemic injury. There is no doubt that mitochondria play a key role in pathogenesis of IRI: dysfunctions of these important organelles alter cell homeostasis and survival. It has been demonstrated that during IRI the system of mitochondrial quality control undergoes alterations with the disruption of the complex balance between the processes of mitochondrial fusion, fission, biogenesis and mitophagy. The fundamental role of mitochondria is carried out thanks to the finely regulated connection to other organelles such as plasma membrane, endoplasmic reticulum and nucleus, therefore impairments of these inter-organelle communications exacerbate IRI. This review pointed to enhance the importance of the mitochondrial network in the pathogenesis of IRI with the aim to focus on potential mitochondria-targeting therapies as new approach to control heart tissue damage after ischemia and reperfusion process.

Effective treatment of intractable diseases using nanoparticles to interfere with vascular supply and angiogenic process

Angiogenesis is a vital biological process involving blood vessels forming from pre-existing vascular systems. This process contributes to various physiological activities, including embryonic development, hair growth, ovulation, menstruation, and the repair and regeneration of damaged tissue. On the other hand, it is essential in treating a wide range of pathological diseases, such as cardiovascular and ischemic diseases, rheumatoid arthritis, malignancies, ophthalmic and retinal diseases, and other chronic conditions. These diseases and disorders are frequently treated by regulating angiogenesis by utilizing a variety of pro-angiogenic or anti-angiogenic agents or molecules by stimulating or suppressing this complicated process, respectively. Nevertheless, many traditional angiogenic therapy techniques suffer from a lack of ability to achieve the intended therapeutic impact because of various constraints. These disadvantages include limited bioavailability, drug resistance, fast elimination, increased price, nonspecificity, and adverse effects. As a result, it is an excellent time for developing various pro- and anti-angiogenic substances that might circumvent the abovementioned restrictions, followed by their efficient use in treating disorders associated with angiogenesis. In recent years, significant progress has been made in different fields of medicine and biology, including therapeutic angiogenesis. Around the world, a multitude of research groups investigated several inorganic or organic nanoparticles (NPs) that had the potential to effectively modify the angiogenesis processes by either enhancing or suppressing the process. Many studies into the processes behind NP-mediated angiogenesis are well described. In this article, we also cover the application of NPs to encourage tissue vascularization as well as their angiogenic and anti-angiogenic effects in the treatment of several disorders, including bone regeneration, peripheral vascular disease, diabetic retinopathy, ischemic stroke, rheumatoid arthritis, post-ischemic cardiovascular injury, age-related macular degeneration, diabetic retinopathy, gene delivery-based angiogenic therapy, protein delivery-based angiogenic therapy, stem cell angiogenic therapy, and diabetic retinopathy, cancer that may benefit from the behavior of the nanostructures in the vascular system throughout the body. In addition, the accompanying difficulties and potential future applications of NPs in treating angiogenesis-related diseases and antiangiogenic therapies are discussed.

Dietary 7-ketocholesterol exacerbates myocardial ischemia-reperfusion injury in mice through monocyte/macrophage-mediated inflammation

Emerging evidence suggests that 7-ketocholesterol (7-KC), one of the most abundant dietary oxysterols, causes inflammation and cardiovascular diseases. Here we show the deteriorating effects of dietary 7-KC on myocardial ischemia-reperfusion (IR) injury and detailed the molecular mechanisms. A high-fat high-cholesterol diet containing 7-KC (7KWD) for 3 weeks increased the plasma 7-KC level compared with high-fat high-cholesterol diet in mice. In wild-type mice but not in CCR2-/- mice, dietary 7-KC increased the myocardial infarct size after IR. Flow cytometry revealed that the ratio of Ly-6Chigh inflammatory monocytes to total monocytes was increased in the 7KWD group. Unbiased RNA sequencing using murine primary macrophages revealed that 7-KC regulated the expression of transcripts related to inflammation and cholesterol biosynthesis. We further validated that in vitro, 7-KC induced endoplasmic reticulum stress, mitochondrial reactive oxygen species production, and nuclear factor-kappa B activation, which are associated with increased mRNA levels of proinflammatory cytokines. Administration of N-acetyl-L-cysteine or siRNA-mediated knockdown of PKR-like endoplasmic reticulum kinase or endoplasmic reticulum oxidase 1α suppressed the levels of 7-KC-induced inflammation. Dietary 7-KC exacerbates myocardial IR injury through monocyte/macrophage-mediated inflammation. Endoplasmic reticulum stress and oxidative stress are involved in the 7-KC-induced proinflammatory response in macrophages.

Mitochondrial Damage in Myocardial Ischemia/Reperfusion Injury and Application of Natural Plant Products

Ischemic heart disease (IHD) is currently one of the leading causes of death among cardiovascular diseases worldwide. In addition, blood reflow and reperfusion paradoxically also lead to further death of cardiomyocytes and increase the infarct size. Multiple evidences indicated that mitochondrial function and structural disorders were the basic driving force of IHD. We summed up the latest evidence of the basic associations and underlying mechanisms of mitochondrial damage in the event of ischemia/reperfusion (I/R) injury. This review then reviewed natural plant products (NPPs) which have been demonstrated to mitochondria-targeted therapeutic effects during I/R injury and the potential pathways involved. We realized that NPPs mainly maintained the integrality of mitochondria membrane and ameliorated dysfunction, such as improving abnormal mitochondrial calcium handling and inhibiting oxidative stress, so as to protect cardiomyocytes during I/R injury. This information will improve our knowledge of mitochondrial biology and I/R-induced injury's pathogenesis and exhibit that NPPs hold promise for translation into potential therapies that target mitochondria.

Nanoparticles Based on Cross-Linked Poly(Lipoic Acid) Protect Macrophages and Cardiomyocytes from Oxidative Stress and Ischemia Reperfusion Injury

The control of radical damage and oxidative stress, phenomena involved in a large number of human pathologies, is a major pharmaceutical and medical goal. We here show that two biocompatible formulations of Pluronic-stabilized, poly (lipoic acid)-based nanoparticles (NP) effectively antagonized the formation of radicals and reactive oxygen species (ROS). These NPs, not only intrinsically scavenged radicals in a-cellular DPPH/ABTS assays, but also inhibited the overproduction of ROS induced by tert-Butyl hydroperoxide (t-BHP) in tumor cells (HeLa), human macrophages and neonatal rat ventricular myocytes (NRVMs). NPs were captured by macrophages and cardiomyocytes much more effectively as compared to HeLa cells and non-phagocytic leukocytes, eventually undergoing intracellular disassembly. Notably, NPs decreased the mitochondrial ROS generation induced by simulated Ischemia/Reperfusion Injury (IRI) in isolated cardiomyocytes. NPs also prevented IRI-triggered cardiomyocyte necrosis, mitochondrial dysfunction, and alterations of contraction-related intracellular Ca2+ waves. Hence, NPs appear to be an effective and cardiomyocyte-selective drug to protect against damages induced by post-ischemic reperfusion.

Mitochondria-Targeted, Nanoparticle-Based Drug-Delivery Systems: Therapeutics for Mitochondrial Disorders

Apart from ATP generation, mitochondria are involved in a wide range of functions, making them one of the most prominent organelles of the human cell. Mitochondrial dysfunction is involved in the pathophysiology of several diseases, such as cancer, neurodegenerative diseases, cardiovascular diseases, and metabolic disorders. This makes it a target for a variety of therapeutics for the diagnosis and treatment of these diseases. The use of nanoparticles to target mitochondria has significant importance in modern times because they provide promising ways to deliver drug payloads to the mitochondria by overcoming challenges, such as low solubility and poor bioavailability, and also resolve the issues of the poor biodistribution of drugs and pharmacokinetics with increased specificity. This review assesses nanoparticle-based drug-delivery systems, such as liposomes, DQAsome, MITO-Porters, micelles, polymeric and metal nanocarriers, as well as quantum dots, as mitochondria-targeted strategies and discusses them as a treatment for mitochondrial disorders.

New diagnostic and therapeutic strategies for myocardial infarction via nanomaterials

Myocardial infarction is lethal to patients because of insufficient blood perfusion to vital organs. Several attempts have been made to improve its prognosis, among which nanomaterial research offers an opportunity to address this problem at the molecular level and has the potential to improve disease prevention, diagnosis, and treatment significantly. Up to now, nanomaterial-based technology has played a crucial role in broad novel diagnostic and therapeutic strategies for cardiac repair. This review summarizes various nanomaterial applications in myocardial infarction from multiple aspects, including high precision detection, pro-angiogenesis, regulating immune homeostasis, and miRNA and stem cell delivery vehicles. We also propose promising research hotspots that have not been reported much yet, such as conjugating pro-angiogenetic elements with nanoparticles to construct drug carriers, developing nanodrugs targeting other immune cells except for macrophages in the infarcted myocardium or the remote region. Though most of those strategies are preclinical and lack clinical trials, there is tremendous potential for their further applications in the future.

Therapeutic Peptides to Treat Myocardial Ischemia-Reperfusion Injury

Cardiovascular diseases (CVD) including acute myocardial infarction (AMI) rank first in worldwide mortality and according to the World Health Organization (WHO), they will stay at this rank until 2030. Prompt revascularization of the occluded artery to reperfuse the myocardium is the only recommended treatment (by angioplasty or thrombolysis) to decrease infarct size (IS). However, despite beneficial effects on ischemic lesions, reperfusion leads to ischemia-reperfusion (IR) injury related mainly to apoptosis. Improvement of revascularization techniques and patient care has decreased myocardial infarction (MI) mortality however heart failure (HF) morbidity is increasing, contributing to the cost-intense worldwide HF epidemic. Currently, there is no treatment for reperfusion injury despite promising results in animal models. There is now an obvious need to develop new cardioprotective strategies to decrease morbidity/mortality of CVD, which is increasing due to the aging of the population and the rising prevalence rates of diabetes and obesity. In this review, we will summarize the different therapeutic peptides developed or used focused on the treatment of myocardial IR injury (MIRI). Therapeutic peptides will be presented depending on their interacting mechanisms (apoptosis, necroptosis, and inflammation) reported as playing an important role in reperfusion injury following myocardial ischemia. The search and development of therapeutic peptides have become very active, with increasing numbers of candidates entering clinical trials. Their optimization and their potential application in the treatment of patients with AMI will be discussed.

Molecular Signaling to Preserve Mitochondrial Integrity against Ischemic Stress in the Heart: Rescue or Remove Mitochondria in Danger

Cardiovascular diseases are one of the leading causes of death and global health problems worldwide, and ischemic heart disease is the most common cause of heart failure (HF). The heart is a high-energy demanding organ, and myocardial energy reserves are limited. Mitochondria are the powerhouses of the cell, but under stress conditions, they become damaged, release necrotic and apoptotic factors, and contribute to cell death. Loss of cardiomyocytes plays a significant role in ischemic heart disease. In response to stress, protective signaling pathways are activated to limit mitochondrial deterioration and protect the heart. To prevent mitochondrial death pathways, damaged mitochondria are removed by mitochondrial autophagy (mitophagy). Mitochondrial quality control mediated by mitophagy is functionally linked to mitochondrial dynamics. This review provides a current understanding of the signaling mechanisms by which the integrity of mitochondria is preserved in the heart against ischemic stress.