Distribution of Systemically Administered Nanoparticles Reveals a Size-Dependent Effect Immediately following Cardiac Ischaemia-Reperfusion Injury

Management of ROS and Regulatory Cell Death in Myocardial Ischemia-Reperfusion Injury

Myocardial ischemia-reperfusion injury (MIRI) is fatal to patients, leading to cardiomyocyte death and myocardial remodeling. Reactive oxygen species (ROS) and oxidative stress play important roles in MIRI. There is a complex crosstalk between ROS and regulatory cell deaths (RCD) in cardiomyocytes, such as apoptosis, pyroptosis, autophagy, and ferroptosis. ROS is a double-edged sword. A reasonable level of ROS maintains the normal physiological activity of myocardial cells. However, during myocardial ischemia-reperfusion, excessive ROS generation accelerates myocardial damage through a variety of biological pathways. ROS regulates cardiomyocyte RCD through various molecular mechanisms. Targeting the removal of excess ROS has been considered an effective way to reverse myocardial damage. Many studies have applied antioxidant drugs or new advanced materials to reduce ROS levels to alleviate MIRI. Although the road from laboratory to clinic has been difficult, many scholars still persevere. This article reviews the molecular mechanisms of ROS inhibition to regulate cardiomyocyte RCD, with a view to providing new insights into prevention and treatment strategies for MIRI.

Recent Advances in Aptamers-Based Nanosystems for Diagnosis and Therapy of Cardiovascular Diseases: An Updated Review

The increasing global prevalence of cardiovascular diseases highlights the urgent need for innovative diagnostic and therapeutic strategies. Aptamers, small single-stranded nucleic acid molecules with exceptional specificity and affinity for target biomolecules, have emerged as promising tools for precise diagnostics and targeted therapies. Their selective binding capabilities provide valuable insights into the molecular mechanisms underlying cardiovascular conditions. When integrated into nanosystems, aptamers enhance the delivery, bioavailability, and stability of diagnostic and therapeutic agents, addressing challenges of solubility and degradation. This integration enables more targeted drug delivery, advanced imaging techniques, and improved therapeutic interventions, ultimately improving the management of cardiovascular diseases. Recent advancements in aptamer selection methodologies, coupled with their unique three-dimensional structures, have significantly expanded their application potential in cardiovascular health. By combining aptamers with nanosystems, novel approaches to cardiovascular disease diagnosis and treatment are emerging, promising enhanced efficacy, safety, and precision. This review explores recent progress in the development and application of aptamer-based nanosystems in cardiovascular diagnostics and therapies.

Iron chelators loaded on myocardiocyte mitochondria-targeted nanozyme system for treating myocardial ischemia-reperfusion injury in mouse models

Ferroptosis plays a critical role in myocardial ischemia-reperfusion injury (MIRI), posing a significant clinical challenge. Nanoenzymes like cerium oxide (CeO2) hold promise for mitigating oxidative damage and inhibiting ferroptosis, but their delivery efficiency and biological activity require optimization. This study aims to develop a targeted nanozyme delivery system for MIRI treatment by integrating CeO2 with mesoporous polydopamine (mPDA) and dexrazoxane (DXZ) to achieve synergistic therapeutic effects. A biomineralization technique was used to synthesize CeO2 nanoparticles (2-3 nm) within mPDA, forming ~ 130 nm composite nanoparticles (Ce@mPDA). Surface modifications with cardiac homing peptide (CHP) and triphenylphosphine (TPP) enabled hierarchical targeting to injured myocardium and mitochondria. DXZ-loaded Ce@mPDA-C/P nanoparticles (D/Ce@mPDA-C/P) were evaluated in vitro and in a MIRI mouse model for their effects on oxidative stress, ferroptosis, apoptosis, inflammation, and cardiac function. D/Ce@mPDA-C/P nanoparticles exhibited robust ROS scavenging, sustained DXZ release, and efficient myocardial and mitochondrial targeting. The D/Ce@mPDA-C/P system significantly reduced oxidative stress, upregulated GPX4 expression, inhibited ferroptosis, and modulated the inflammatory microenvironment. Long-term studies in a MIRI mouse model demonstrated reductions in myocardial fibrosis and improvements in cardiac function, including enhanced fractional shortening and ejection fraction. This hierarchical targeting delivery system effectively combines the antioxidant properties of CeO2 with the iron-chelating effects of DXZ, providing a promising therapeutic strategy for MIRI. This approach may expand the clinical use of DXZ and advance nanomedicine-based interventions for myocardial repair.

The future of cardiac repair: a review on cell-free nanotherapies for regenerative myocardial infarction

Cardiovascular diseases as myocardial infarction (MI) represent a major cause for morbidity and mortality worldwide. Even though, patients who survive MI are susceptible to high risk of heart failure. This is mainly attributed to the major loss of cardiomyocytes and limited regenerative potential of myocardium. Despite the availability of various cardiovascular drugs, they fail to address the main cause of MI. The optimum therapeutic goal should therefore focus on enhancing cardiac regeneration through cellular and cell-free therapeutic approaches. This review focused on different mechanisms of cardiac regeneration that can be achieved via non-cellular therapeutic modalities. Passive and active targeting of the infarcted myocardium using various nanoparticles that can be loaded with growth factors, drugs or affordable natural products can reduce negative ventricular remodeling, infarct size and the apoptotic rate of cardiomyocytes. In addition, injectable biomaterials-based nanocomposite can be used as a scaffold to support infarcted heart and recruit cells. Innovative affordable and less invasive cell-free approaches can be implemented to enhance cardiac regeneration post MI.

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.

In situ-crosslinked Zippersomes enhance cardiac repair by increasing accumulation and retention

Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) are a promising treatment for myocardial infarction (MI), but their therapeutic efficacy is limited by inefficient accumulation at the target site. A minimally invasive MSC EV therapy that enhances EV accumulation at the disease site and extends EV retention could significantly improve post-infarct cardiac regeneration. Here, we show that EVs decorated with the next-generation of high-affinity (HiA) heterodimerizing leucine zippers, termed HiA Zippersomes, amplify targetable surface areas through in situ crosslinking and exhibited ~7-fold enhanced accumulation within the infarcted myocardium in mice after 3 days and continued to be retained up to Day 21, surpassing the performance of unmodified EVs. After MI in mice, HiA Zippersomes increase the ejection fraction by 53% and 100% compared with unmodified EVs and phosphate-buffered saline (PBS), respectively. This notable improvement in cardiac function played a crucial role in restoring healthy heart performance. HiA Zippersomes also robustly decrease infarct size by 52% and 60% compared with unmodified EVs and PBS, respectively, thus representing a promising platform for minimally invasive vesicle delivery to the infarcted heart compared to intramyocardial injections.

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.

Cardiac-targeted and ROS-responsive liposomes containing puerarin for attenuating myocardial ischemia-reperfusion injury

Aim: This study aimed to construct an ischemic cardiomyocyte-targeted and ROS-responsive drug release system to reduce myocardial ischemia-reperfusion injury (MI/RI).Methods: We constructed thioketal (TK) and cardiac homing peptide (CHP) dual-modified liposomes loaded with puerarin (PUE@TK/CHP-L), which were expected to deliver drugs precisely into ischemic cardiomyocytes and release drugs in response to the presence of high intracellular ROS levels. The advantages of PUE@TK/CHP-L were assessed by cellular pharmacodynamics, in vivo fluorescence imaging and animal pharmacodynamics.Results: PUE@TK/CHP-L significantly inhibited apoptosis and ferroptosis in H/R-injured cardiomyocytes and also actively targeted ischemic myocardium. Based on these advantages, PUE@TK/CHP-L could significantly enhance the drug's ability to attenuate MI/RI.Conclusion: PUE@TK/CHP-L had potential clinical value in the precise treatment of MI/RI.

Fillable Magnetic Microrobots for Drug Delivery to Cardiac Tissues In Vitro

Many cardiac diseases, such as arrhythmia or cardiogenic shock, cause irregular beating patterns that must be regulated to prevent disease progression toward heart failure. Treatments can include invasive surgery or high systemic drug dosages, which lack precision, localization, and control. Drug delivery systems (DDSs) that can deliver cargo to the cardiac injury site could address these unmet clinical challenges. Here, a microrobotic DDS that can be mobilized to specific sites via magnetic control is presented. This DDS incorporates an internal chamber that can protect drug cargo. Furthermore, the DDS contains a tunable thermosensitive sealing layer that gradually degrades upon exposure to body temperature, enabling prolonged drug release. Once loaded with the small molecule drug norepinephrine, this microrobotic DDS modulated beating frequency in induced pluripotent stem-cell derived cardiomyocytes (iPSC-CMs) in a dose-dependent manner, thus simulating drug delivery to cardiac cells in vitro. The DDS also navigates several maze-like structures seeded with cardiomyocytes to demonstrate precise locomotion under a rotating low-intensity magnetic field and on-site drug delivery. This work demonstrates the utility of a magnetically actuating DDS for precise, localized, and controlled drug delivery which is of interest for a myriad of future opportunities such as in treating cardiac diseases.

RGD-modified ZIF-8 nanoparticles as a drug carrier for MR imaging and targeted drug delivery in myocardial infarction

Aim: A multifunctional nanoplatform has been developed to enhance the targeting capability and biosafety of drug/siRNA for better diagnosis and treatment of myocardial infarction (MI).Materials & methods: The nanoplatform's chemical properties, biodistribution, cardiac magnetic resonance imaging (MRI) capabilities, therapeutic effects and biocompatibility were investigated.Results: The nanoplatform exhibited MI-targeting properties and pH-sensitivity, allowing for effective cardiac MRI and delivery of drugs to the infarcted myocardium. The GCD/Qt@ZIF-RGD demonstrated potential as a reliable MRI probe for MI diagnosis. Moreover, the GCD/si-SHP1/Qt@ZIF-RGD effectively suppressed SHP-1 expression, increased pro-angiogenesis gene expression and reduced cell apoptosis in HUVECs exposed to hypoxia/reoxygenation.Conclusion: Our newly developed multifunctional drug delivery system shows promise as a nanoplatform for both the diagnosis and treatment of MI.

Novel cutting edge nano-strategies to address old long-standing complications in cardiovascular diseases. A comprehensive review

BACKGROUND

Cardiovascular diseases (CVD) impact a substantial portion of the global population and represent a significant threat to experiencing life-threatening outcomes, such as atherosclerosis, myocardial infarction, stroke and heart failure. Despite remarkable progress in pharmacology and medical interventions, CVD persists as a major public health concern, and now ranks as the primary global cause of death and the highest consumer of global budgets. Ongoing research endeavours persist in seeking novel therapeutic avenues and interventions to deepen our understanding of CVD, enhance prevention measures, and refine treatment strategies.

METHODS

Nanotechnology applied to the development of new molecular probes with diagnostic and theranostic properties represents one of the greatest technological challenges in preclinical and clinical research.

RESULTS

The application of nanotechnology in cardiovascular medicine holds great promise for advancing our understanding of CVDs and revolutionizing their diagnosis and treatment strategies, ultimately improving patient care and outcomes. In addition, the capacity of drug encapsulation in nanoparticles has significantly bolstered their biological safety, bioavailability and solubility. In combination with imaging technologies, molecular imaging has emerged as a pivotal therapeutic tool, offering insight into the molecular events underlying disease and facilitating targeted treatment approaches.

CONCLUSION

Here, we present a comprehensive overview of the recent advancements in targeted nanoparticle approaches for diagnosing CVDs, encompassing molecular imaging techniques, underscoring the significant progress in theranostic, as a novel and promising therapeutic strategy.

Extracellular vesicles purified from serum-converted human platelet lysates offer strong protection after cardiac ischaemia/reperfusion injury

Extracellular vesicles (EVs) from cultured cells or bodily fluids have been demonstrated to show therapeutic value following myocardial infarction. However, challenges in donor variation, EV generation and isolation methods, and material availability have hindered their therapeutic use. Here, we show that human clinical-grade platelet concentrates from a blood establishment can be used to rapidly generate high concentrations of high purity EVs from sero-converted platelet lysate (SCPL-EVs) with minimal processing, using size-exclusion chromatography. Processing removed serum carrier proteins, coagulation factors and complement proteins from the original platelet lysate and the resultant SCPL-EVs carried a range of trophic factors and multiple recognised cardioprotective miRNAs. As such, SCPL-EVs protected rodent and human cardiomyocytes from hypoxia/re-oxygenation injury and stimulated angiogenesis of human cardiac microvessel endothelial cells. In a mouse model of myocardial infarction with reperfusion, SCPL-EV delivery using echo-guided intracavitary percutaneous injection produced large improvements in cardiac function, reduced scar formation and promoted angiogenesis. Since platelet-based biomaterials are already widely used clinically, we believe that this therapy could be rapidly suitable for a human clinical trial.

One Endothelium-Targeted Combined Nucleic Acid Delivery System for Myocardial Infarction Therapy

Acute myocardial infarction (MI) and ischemic heart disease are the leading causes of heart failure and mortality. Currently, research on MI treatment is focused on angiogenic and anti-inflammatory therapies. Although endothelial cells (ECs) are critical for triggering inflammation and angiogenesis, no approach has targeted them for the treatment of MI. In this study, we proposed a nonviral combined nucleic acid delivery system consisting of an EC-specific polycation (CRPPR-grafted ethanolamine-modified poly(glycidyl methacrylate), CPC) that can efficiently codeliver siR-ICAM1 and pCXCL12 for the treatment of MI. Animals treated with the combination therapy exhibited better cardiac function than those treated with each nucleic acid alone. In particular, the combination therapy of CPC/siR-ICAM1 and CPC/pCXCL12 significantly improved cardiac systolic function, anti-inflammatory responses, and angiogenesis compared to the control group. In conclusion, CPC-based combined gene delivery systems show impressive performance in the treatment of MI and provide a programmed strategy for the development of codelivery systems for various EC-related diseases.

In Situ-Crosslinked Zippersomes Enhance Cardiac Repair by Increasing Accumulation and Retention

Mesenchymal stem cell (MSC)-derived extracellular vesicles (EVs) are a promising treatment for myocardial infarction, but their therapeutic efficacy is limited by inefficient accumulation at the target site. A non-invasive MSC EV therapy that enhances EV accumulation at the disease site and extends EV retention could significantly improve post-infarct cardiac regeneration. Here we show that EVs decorated with the next-generation of high-affinity heterodimerizing leucine zippers, termed high-affinity (HiA) Zippersomes, amplify targetable surface areas through in situ crosslinking and exhibited ∼7-fold enhanced accumulation within the infarcted myocardium in mice after three days and continued to be retained up to day 21, surpassing the performance of unmodified EVs. After myocardial infarction in mice, high-affinity Zippersomes increase the ejection fraction by 53% and 100% compared with unmodified EVs and PBS, respectively. This notable improvement in cardiac function played a crucial role in restoring healthy heart performance. High-affinity Zippersomes also robustly decrease infarct size by 52% and 60% compared with unmodified EVs and PBS, respectively, thus representing a promising platform for non-invasive vesicle delivery to the infarcted heart.

Translational Impact Statement

Therapeutic delivery to the heart remains inefficient and poses a bottleneck in modern drug delivery. Surgical application and intramyocardial injection of therapeutics carry high risks for most heart attack patients. To address these limitations, we have developed a non-invasive strategy for efficient cardiac accumulation of therapeutics using in situ crosslinking. Our approach achieves high cardiac deposition of therapeutics without invasive intramyocardial injections. Patients admitted with myocardial infarction typically receive intravenous access, which would allow painless administration of Zippersomes alongside standard of care.

Exploring and Analyzing the Systemic Delivery Barriers for Nanoparticles

Most nanomedicines require efficient in vivo delivery to elicit diagnostic and therapeutic effects. However, en route to their intended tissues, systemically administered nanoparticles often encounter delivery barriers. To describe these barriers, we propose the term "nanoparticle blood removal pathways" (NBRP), which summarizes the interactions between nanoparticles and the body's various cell-dependent and cell-independent blood clearance mechanisms. We reviewed nanoparticle design and biological modulation strategies to mitigate nanoparticle-NBRP interactions. As these interactions affect nanoparticle delivery, we studied the preclinical literature from 2011-2021 and analyzed nanoparticle blood circulation and organ biodistribution data. Our findings revealed that nanoparticle surface chemistry affected the in vivo behavior more than other nanoparticle design parameters. Combinatory biological-PEG surface modification improved the blood area under the curve by ~418%, with a decrease in liver accumulation of up to 47%. A greater understanding of nanoparticle-NBRP interactions and associated delivery trends will provide new nanoparticle design and biological modulation strategies for safer, more effective, and more efficient nanomedicines.

Diagnostic and Therapeutic Aptamers: A Promising Pathway to Improved Cardiovascular Disease Management

Despite advances in care, cardiovascular diseases remain the leading cause of death worldwide. As a result, identifying suitable biomarkers for early diagnosis and improving therapeutic and diagnostic strategies is crucial. Because of their significant advantages over other therapeutic approaches, nucleic-based therapies, particularly aptamers, are gaining increased attention. Aptamers are innovative synthetic polymers or oligomers of single-stranded DNA (ssDNA) or RNA molecules that can form 3-dimensional structures and thus interact with their targets with high specificity and affinity. Furthermore, they outperform classical protein-based antibodies in terms of in vitro selection, production, ease of modification and conjugation, high stability, low immunogenicity, and suitability for nanoparticle functionalization for targeted drug delivery. This work aims to review the advances made in the aptamers' field in biomarker detection, diagnosis, imaging, and targeted therapy, which highlight their huge potential in the management of cardiovascular diseases.

Expanding applications of allogeneic platelets, platelet lysates, and platelet extracellular vesicles in cell therapy, regenerative medicine, and targeted drug delivery

Platelets are small anucleated blood cells primarily known for their vital hemostatic role. Allogeneic platelet concentrates (PCs) collected from healthy donors are an essential cellular product transfused by hospitals to control or prevent bleeding in patients affected by thrombocytopenia or platelet dysfunctions. Platelets fulfill additional essential functions in innate and adaptive immunity and inflammation, as well as in wound-healing and tissue-repair mechanisms. Platelets contain mitochondria, lysosomes, dense granules, and alpha-granules, which collectively are a remarkable reservoir of multiple trophic factors, enzymes, and signaling molecules. In addition, platelets are prone to release in the blood circulation a unique set of extracellular vesicles (p-EVs), which carry a rich biomolecular cargo influential in cell-cell communications. The exceptional functional roles played by platelets and p-EVs explain the recent interest in exploring the use of allogeneic PCs as source material to develop new biotherapies that could address needs in cell therapy, regenerative medicine, and targeted drug delivery. Pooled human platelet lysates (HPLs) can be produced from allogeneic PCs that have reached their expiration date and are no longer suitable for transfusion but remain valuable source materials for other applications. These HPLs can substitute for fetal bovine serum as a clinical grade xeno-free supplement of growth media used in the in vitro expansion of human cells for transplantation purposes. The use of expired allogeneic platelet concentrates has opened the way for small-pool or large-pool allogeneic HPLs and HPL-derived p-EVs as biotherapy for ocular surface disorders, wound care and, potentially, neurodegenerative diseases, osteoarthritis, and others. Additionally, allogeneic platelets are now seen as a readily available source of cells and EVs that can be exploited for targeted drug delivery vehicles. This article aims to offer an in-depth update on emerging translational applications of allogeneic platelet biotherapies while also highlighting their advantages and limitations as a clinical modality in regenerative medicine and cell therapies.

VEGF mimetic peptide-conjugated nanoparticles for magnetic resonance imaging and therapy of myocardial infarction

To reduce the mortality of myocardial infarction (MI), accurate detection of the infarct and appropriate prevention against ischemia/reperfusion (I/R) induced cardiac dysfunction are highly desired. Considering that vascular endothelial growth factor (VEGF) receptors are overexpressed in the infarcted heart and VEGF mimetic peptide QK binds specifically to VEGF receptors and activates vascularization, the PEG-QK-modified, gadolinium-doped carbon dots (GCD-PEG-QK) were formulated. This research aims to investigate the magnetic resonance imaging (MRI) capability of GCD-PEG-QK on myocardial infarct and their therapeutic effect on I/R-induced myocardial injury. These multifunctional nanoparticles exhibited good colloidal stability, excellent fluorescent and magnetic property, and satisfactory biocompatibility. Intravenous injection of GCD-PEG-QK nanoparticles post myocardial I/R displayed accurate MRI of the infarct, enhanced efficacy of QK peptide on pro-angiogenesis, and amelioration of cardiac fibrosis, remodeling and dysfunction, probably via the improvement on QK's in vivo stability and MI-targeting. Collectively, the data suggested that this theranostic nanomedicine can realize precise MRI and effective therapy for acute MI in a non-invasive manner.

Size effect of fluorescent thiol-organosilica particles on their distribution in the mouse spleen

We investigated the distribution of intravenously administered thiol-organosilica particle (thiol-OS) in the spleen to evaluate their size effect in mice. A single administration of particles of thiol-OS containing rhodamine B (Rh) (90, 280, 340, 450, 630, 1110, 1670, and 3030 nm in diameter) was performed. After 24 h, we conducted a combination analysis using histological studies by fluorescent microscopy and quantitative inductively coupled plasma optical emission spectrometry (ICP-OES), which revealed no clear correlation between the particle size and spleen uptake of particle weight and number per tissue weight, and the injection dose. Moreover, Rh with 450 nm diameter (Rh450) showed the highest uptake, and Rh with 340 nm diameter (Rh340) showed the lowest uptake. Histologically, large fluorescent areas in the marginal zone (MZ) and red pulp (RP) of the spleen were observed for all particle sizes, but less in the follicle of white pulp. Using combination analysis using the particle weights of ICP-OES and the fluorescent area, we compared the distributions of each particle in each region. Rh450 had the largest accumulated weight in the MZ and RP. Particles larger than Rh450 showed negative correlations between their sizes and accumulated weight in the MZ and RP. Simultaneous dual administration of particles using Rhs and thiol-OS containing fluorescein (90 nm in diameter) showed the size-dependent difference in cellular distribution and intracellular localization. Immunohistochemical staining against macrophage markers, CD169, and F4/80 showed various colocalization patterns with macrophages that uptook particles, indicating differences in particle uptake in each macrophage may have novel significance.

Preventing ischemia-reperfusion injury by acousto-mechanical local oxygen delivery

Ischemia-reperfusion (I/R) injury is a pathological process that causes vascular damage and dysfunction which increases recurrence and/or mortality in myocardial infarction, ischemic stroke, and organ transplantation. We hypothesized that ultrasound-stimulated oxygen-loaded microbubble (O₂-MB) cavitation would enhance mechanical force on endothelium and simultaneously release oxygen locally at the targeted vessels. This cooperation between biomechanical and biochemical stimuli might modulate endothelial metabolism, providing a potential clinical approach to the prevention of I/R injury. Murine hindlimb and cardiac I/R models were used to demonstrate the feasibility of injury prevention by O₂-MB cavitation. Increased mechanical force on endothelium induced eNOS-activated vasodilation and angiogenesis to prevent re-occlusion at the I/R vessels. Local oxygen therapy increased endothelial oxygenation that inhibited HIF-1α expression, increased ATP generation, and activated cyclin D1 for cell repair. Moreover, a decrease in interstitial H₂O₂ level reduced the expression of caspase3, NFκB, TNFα, and IL6, thus ameliorating inflammatory responses. O₂-MB cavitation showed efficacy in maintaining cardiac function and preventing myocardial fibrosis after I/R. Finally, we present a potential pathway for the modulation of endothelial metabolism by O₂-MB cavitation in relation to I/R injury, wound healing, and vascular bioeffects.

Role of polyphenolic compounds and their nanoformulations: a comprehensive review on cross-talk between chronic kidney and cardiovascular diseases

Chronic kidney disease (CKD) affects a huge portion of the world's population and frequently leads to cardiovascular diseases (CVDs). It might be because of common risk factors between chronic kidney disease and cardiovascular diseases. Renal dysfunction caused by chronic kidney disease creates oxidative stress which in turn leads to cardiovascular diseases. Oxidative stress causes endothelial dysfunction and inflammation in heart which results in atherosclerosis. It ends in clogging of veins and arteries that causes cardiac stroke and myocardial infarction. To develop an innovative therapeutic approach and new drugs to treat these diseases, it is important to understand the pathophysiological mechanism behind the CKD and CVDs and their interrelationship. Natural phytoconstituents of plants such as polyphenolic compounds are well known for their medicinal value. Polyphenols are plant secondary metabolites with immense antioxidant properties, which can protect from free radical damage. Nowadays, polyphenols are generating a lot of buzz in the scientific community because of their potential health benefits especially in the case of heart and kidney diseases. This review provides a detailed account of the pathophysiological link between CKD and CVDs and the pharmacological potential of polyphenols and their nanoformulations in promoting cardiovascular and renal health.

Advances in nanomaterial-based targeted drug delivery systems

Nanomaterial-based drug delivery systems (NBDDS) are widely used to improve the safety and therapeutic efficacy of encapsulated drugs due to their unique physicochemical and biological properties. By combining therapeutic drugs with nanoparticles using rational targeting pathways, nano-targeted delivery systems were created to overcome the main drawbacks of conventional drug treatment, including insufficient stability and solubility, lack of transmembrane transport, short circulation time, and undesirable toxic effects. Herein, we reviewed the recent developments in different targeting design strategies and therapeutic approaches employing various nanomaterial-based systems. We also discussed the challenges and perspectives of smart systems in precisely targeting different intravascular and extravascular diseases.

Strategies and challenges for non-viral delivery of non-coding RNAs to the heart

Non-coding RNAs (ncRNAs), such as miRNAs and long non-coding RNAs (lncRNAs) have been reported as regulators of cardiovascular pathophysiology. Their transient effect and diversified mechanisms of action offer a plethora of therapeutic opportunities for cardiovascular diseases (CVDs). However, physicochemical RNA features such as charge, stability, and structural organization hinder efficient on-target cellular delivery. Here, we highlight recent preclinical advances in ncRNA delivery for the cardiovascular system using non-viral approaches. We identify the unmet needs and advance possible solutions towards clinical translation. Finding the optimal delivery vehicle and administration route is vital to improve therapeutic efficacy and safety; however, given the different types of ncRNAs, this may ultimately not be frameable within a one-size-fits-all approach.

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.

Albumin-templated manganese carbonate nanoparticles for precise magnetic resonance imaging of acute myocardial infarction

Myocardial infarction (MI) is a major cause of death worldwide. Early and precise diagnosis of myocardial viability after MI is extremely important for effective treatment and prognosis evaluation. Herein, we developed the BSA-templated manganese carbonate (MnCO₃@BSA) nanoparticles as an MR imaging contrast agent for accurate detection of the infarcted regions. The chemophysical features, targeting capability toward the infarct, and biocompatibility were evaluated. The nanoparticles showed superior chemical stability. In vitro study suggested that the MnCO₃@BSA nanoparticles do not enter normal cardiomyocytes. MR imaging indicated that the MnCO₃@BSA with a high longitudinal (r₁) relaxivity of 5.84 mM^-1s^-1 at physiological condition specifically accumulated into the infarcted regions of myocardial ischemia/reperfusion (I/R) mice. In addition, the MnCO₃@BSA nanoparticles exhibited low cytotoxicity to cardiomyocytes, no damage to organs and good hemocompatibility. Thereby, the MnCO₃@BSA nanoparticles manifested great potential as an extracellular contrast agent of MR imaging for sensitive and specific detection of the infarcted regions during acute myocardial I/R injury.

Nanocarrier-Based Targeted Therapies for Myocardial Infarction

Myocardial infarction is a major cause of morbidity and mortality worldwide. Due to poor inherent regeneration of the adult mammalian myocardium and challenges with effective drug delivery, there has been little progress in regenerative therapies. Nanocarriers, including liposomes, nanoparticles, and exosomes, offer many potential advantages for the therapy of myocardial infarction, including improved delivery, retention, and prolonged activity of therapeutics. However, there are many challenges that have prevented the widespread clinical use of these technologies. This review aims to summarize significant principles and developments in the field, with a focus on nanocarriers using ligand-based or cell mimicry-based targeting. Lastly, a discussion of limitations and potential future direction is provided.

Nanosphere size control by varying the ratio of poly(ester amide) block copolymer blends

HYPOTHESIS

Blending amphiphilic triblock (A-B-A) and diblock (A-B) copolymers comprised of the same hydrophobic tyrosine-derived oligomeric B-block and hydrophilic poly(ethylene glycol) methyl ether (mPEG) A-block can provide highly tunable self-assembled nanosphere particle sizes suitable for biomedical applications.

EXPERIMENT

Triblock and diblock copolymers were synthesized via carbodiimide chemistry and were characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The amount of free PEG present in the purified copolymers was determined using a standard addition calibration curve and GPC peak deconvolution methods. Nanospheres were prepared by co-precipitation of each copolymer and of copolymer blends over a range of mole ratios. Nanospheres were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM) and % polymer recovery post-preparation.

FINDING

Precise synthesis control produced triblock and diblock copolymers with narrow molecular weight distributions and minimal residual reactants. Self-assembled nanosphere particle sizes were 33 nm for the triblock and 129 nm for the diblock, and the size of their blends increased continuously as a function of mole ratio within that biomedically relevant range. Addition of unreacted PEG had minimal impact on either triblock or diblock nanosphere particle sizes whereas addition of unreacted oligomeric B-block increased nanosphere sizes.

Polymeric nanoparticles in the diagnosis and treatment of myocardial infarction: Challenges and future prospects

Myocardial infarction (MI) is the leading cause of morbidity and mortality worldwide. Despite extensive efforts to provide early diagnosis and adequate treatment regimens, detection of MI still faces major limitations and pathological MI complications continue to threaten the recovery of survivors. Polymeric nanoparticles (NPs) represent novel noninvasive drug delivery systems for the diagnosis and treatment of MI and subsequent prevention of fatal heart failure. In this review, we cover the recent advances in polymeric NP-based diagnostic and therapeutic approaches for MI and their application as multifunctional theranostic tools. We also discuss the in vivo behavior and toxicity profile of polymeric NPs, their application in noninvasive imaging, passive, and active drug delivery, and use in cardiac regenerative therapy. We conclude with the challenges faced with polymeric nanosystems and suggest future efforts needed for clinical translation.

Design of therapeutic biomaterials to control inflammation

Inflammation plays an important role in the response to danger signals arising from damage to our body and in restoring homeostasis. Dysregulated inflammatory responses occur in many diseases, including cancer, sepsis and autoimmunity. The efficacy of anti-inflammatory drugs, developed for the treatment of dysregulated inflammation, can be potentiated using biomaterials, by improving the bioavailability of drugs and by reducing side effects. In this Review, we first outline key elements and stages of the inflammatory environment and then discuss the design of biomaterials for different anti-inflammatory therapeutic strategies. Biomaterials can be engineered to scavenge danger signals, such as reactive oxygen and nitrogen species and cell-free DNA, in the early stages of inflammation. Materials can also be designed to prevent adhesive interactions of leukocytes and endothelial cells that initiate inflammatory responses. Furthermore, nanoscale platforms can deliver anti-inflammatory agents to inflammation sites. We conclude by discussing the challenges and opportunities for biomaterial innovations in addressing inflammation.

Modulating Nanoparticle Size to Understand Factors Affecting Hemostatic Efficacy and Maximize Survival in a Lethal Inferior Vena Cava Injury Model

Intravenous nanoparticle hemostats offer a potentially attractive approach to promote hemostasis, in particular for inaccessible wounds such as noncompressible torso hemorrhage (NCTH). In this work, particle size was tuned over a range of <100-500 nm, and its effect on nanoparticle-platelet interactions was systematically assessed using in vitro and in vivo experiments. Smaller particles bound a larger percentage of platelets per mass of particle delivered, while larger particles resulted in higher particle accumulation on a surface of platelets and collagen. Intermediate particles led to the greatest platelet content in platelet-nanoparticle aggregates, indicating that they may be able to recruit more platelets to the wound. In biodistribution studies, smaller and intermediate nanoparticles exhibited longer circulation lifetimes, while larger nanoparticles resulted in higher pulmonary accumulation. The particles were then challenged in a 2 h lethal inferior vena cava (IVC) puncture model, where intermediate nanoparticles significantly increased both survival and injury-specific targeting relative to saline and unfunctionalized particle controls. An increase in survival in the second hour was likewise observed in the smaller nanoparticles relative to saline controls, though no significant increase in survival was observed in the larger nanoparticle size. In conjunction with prior in vitro and in vivo experiments, these results suggest that platelet content in aggregates and extended nanoparticle circulation lifetimes are instrumental to enhancing hemostasis. Ultimately, this study elucidates the role of particle size in platelet-particle interactions, which can be a useful tool for engineering the performance of particulate hemostats and improving the design of these materials.

Delivering more for less: nanosized, minimal-carrier and pharmacoactive drug delivery systems

Traditional nanoparticle carriers such as liposomes, micelles, and polymeric vehicles improve drug delivery by protecting, stabilizing, and increasing the circulatory half-life of the encapsulated drugs. However, traditional drug delivery systems frequently suffer from poor drug loading and require an excess of carrier materials. This carrier material excess poses an additional systemic burden through accumulation, if not degradable the need for metabolism, and potential toxicity. To address these shortcomings, minimal-carrier nanoparticle systems and pharmacoactive carrier materials have been developed. Both solutions provide drug delivery systems in which the majority of the nanoparticle is pharmacologically active. While minimal-carrier and pharmacoactive drug delivery systems can improve drug loading, they can also suffer from poor stability. Here, we review minimal-carrier and pharmacoactive delivery systems, discuss ongoing challenges and outline opportunities to translate minimal-carrier and pharmacoactive drug delivery systems into the clinic.

Non-Viral Gene Delivery Systems for Treatment of Myocardial Infarction: Targeting Strategies and Cardiac Cell Modulation

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality worldwide. Conventional therapies involving surgery or pharmacological strategies have shown limited therapeutic effects due to a lack of cardiac tissue repair. Gene therapy has opened an avenue for the treatment of cardiac diseases through manipulating the underlying gene mechanics. Several gene therapies for cardiac diseases have been assessed in clinical trials, while the clinical translation greatly depends on the delivery technologies. Non-viral vectors are attracting much attention due to their safety and facile production compared to viral vectors. In this review, we discuss the recent progress of non-viral gene therapies for the treatment of cardiovascular diseases, with a particular focus on myocardial infarction (MI). Through a summary of delivery strategies with which to target cardiac tissue and different cardiac cells for MI treatment, this review aims to inspire new insights into the design/exploitation of non-viral delivery systems for gene cargos to promote cardiac repair/regeneration.

Reactive oxygen species-based nanomaterials for the treatment of myocardial ischemia reperfusion injuries

Interventional coronary reperfusion strategies are widely adopted to treat acute myocardial infarction, but morbidity and mortality of acute myocardial infarction are still high. Reperfusion injuries are inevitable due to the generation of reactive oxygen species (ROS) and apoptosis of cardiac muscle cells. However, many antioxidant and anti-inflammatory drugs are largely limited by pharmacokinetics and route of administration, such as short half-life, low stability, low bioavailability, and side effects for treatment myocardial ischemia reperfusion injury. Therefore, it is necessary to develop effective drugs and technologies to address this issue. Fortunately, nanotherapies have demonstrated great opportunities for treating myocardial ischemia reperfusion injury. Compared with traditional drugs, nanodrugs can effectively increase the therapeutic effect and reduces side effects by improving pharmacokinetic and pharmacodynamic properties due to nanodrugs’ size, shape, and material characteristics. In this review, the biology of ROS and molecular mechanisms of myocardial ischemia reperfusion injury are discussed. Furthermore, we summarized the applications of ROS-based nanoparticles, highlighting the latest achievements of nanotechnology researches for the treatment of myocardial ischemia reperfusion injury.

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Cardiovascular diseases are the leading cause of death worldwide. Researches of the myocardial infarction pathology and development of new treatments have very important scientific significance in the biomedical field.

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Many nanomaterials have shown amazing therapeutic effects to reduce myocardial damage by eliminating ROS.

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Nanomaterials effectively reduced myocardial damage through eliminating ROS from NOXs, M-ETC, M-Ca²⁺, M-mPTP, and RIRR.

Animal models used in the research of nanoparticles for cardiovascular diseases

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity worldwide. Tremendous progress has been made in the prevention and treatment of CVD; however, there are still lots of limitations and new technology is needed. Nanoparticles have been studied recently for CVD due to their nanoscale size and unique properties, and hold a potential to be a novel therapy for the treatment. To test the safety and effectiveness of drug-loaded nanoparticles for CVD prior to human studies, animal disease models are unavoidably needed. This review summarized the animal models used in the research of nanoparticles for CVD and provided a generic picture of current use of CVD animal models according to the different types of diseases which should be prioritized when considering the application of nanoparticles in treating CVD. This review would be useful resources not only for life science researchers and clinicians but also for those from chemistry and materials sciences background who may not have a systematic knowledge about CVD animal models.

Non-viral nanoparticles for RNA interference: Principles of design and practical guidelines

Ribonucleic acid interference (RNAi) is an innovative treatment strategy for a myriad of indications. Non-viral synthetic nanoparticles (NPs) have drawn extensive attention as vectors for RNAi due to their potential advantages, including improved safety, high delivery efficiency and economic feasibility. However, the complex natural process of RNAi and the susceptible nature of oligonucleotides render the NPs subject to particular design principles and requirements for practical fabrication. Here, we summarize the requirements and obstacles for fabricating non-viral nano-vectors for efficient RNAi. To address the delivery challenges, we discuss practical guidelines for materials selection and NP synthesis in order to maximize RNA encapsulation efficiency and protection against degradation, and to facilitate the cytosolic release of oligonucleotides. The current status of clinical translation of RNAi-based therapies and further perspectives for reducing the potential side effects are also reviewed.

Environmental Fe, Ti, Al, Cu, Hg, Bi, and Si Nanoparticles in the Atrioventricular Conduction Axis and the Associated Ultrastructural Damage in Young Urbanites: Cardiac Arrhythmias Caused by Anthropogenic, Industrial, E-Waste, and Indoor Nanoparticles

Air pollution exposure is a risk factor for arrhythmia. The atrioventricular (AV) conduction axis is key for the passage of electrical signals to ventricles. We investigated whether environmental nanoparticles (NPs) reach the AV axis and whether they are associated with ultrastructural cell damage. Here, we demonstrate the detection of the shape, size, and composition of NPs by transmission electron microscopy (TEM) and energy-dispersive X-ray spectrometry (EDX) in 10 subjects from Metropolitan Mexico City (MMC) with a mean age of 25.3 ± 5.9 and a 71-year-old subject without cardiac pathology. We found that in every case, Fe, Ti, Al, Hg, Cu, Bi, and/or Si spherical or acicular NPs with a mean size of 36 ± 17 nm were present in the AV axis in situ, freely and as conglomerates, within the mitochondria, sarcomeres, lysosomes, lipofuscin, and/or intercalated disks and gap junctions of Purkinje and transitional cells, telocytes, macrophages, endothelium, and adjacent atrial and ventricular fibers. Erythrocytes were found to transfer NPs to the endothelium. Purkinje fibers with increased lysosomal activity and totally disordered myofilaments and fragmented Z-disks exhibited NP conglomerates in association with gap junctions and intercalated disks. AV conduction axis pathology caused by environmental NPs is a plausible and modifiable risk factor for understanding common arrhythmias and reentrant tachycardia. Anthropogenic, industrial, e-waste, and indoor NPs reach pacemaker regions, thereby increasing potential mechanisms that disrupt the electrical impulse pathways of the heart. The cardiotoxic, oxidative, and abnormal electric performance effects of NPs in pacemaker locations warrant extensive research. Cardiac arrhythmias associated with nanoparticle effects could be preventable.

Current Advances in the Use of Nanophytomedicine Therapies for Human Cardiovascular Diseases

Considering the high prevalence of cardiovascular diseases (CVDs), the primary cause of death during the last several decades, it is necessary to develop proper strategies for the prevention and treatment of CVDs. Given the excessive side effects of current therapies, alternative therapeutic approaches like medicinal plants and natural products are preferred. Lower toxicity, chemical diversity, cost-effectiveness, and proven therapeutic potentials make natural products superior compared to other products. Nanoformulation methods improve the solubility, bioavailability, circulation time, surface area-to-volume ratio, systemic adverse side effects, and drug delivery efficiency of these medications. This study intended to review the functionality of the most recent nanoformulated medicinal plants and/or natural products against various cardiovascular conditions such as hypertension, atherosclerosis, thrombosis, and myocardial infarction. Literature review revealed that curcumin, quercetin, and resveratrol were the most applied natural products, respectively. Combination therapy, conjugation, or fabrication of nanoparticles and nanocarriers improved the applications and therapeutic efficacy of herbal- or natural-based nanoformulations. In the context of CVDs prevention and/or treatment, available data suggest that natural-based nanoformulations are considerably efficient, alone or in blend with other herbal/synthetic medicines. However, clinical trials are mandatory to elucidate the safety, cardioprotective effect, and mechanism of actions of nanophytomedicines.

Immune cell shuttle for precise delivery of nanotherapeutics for heart disease and cancer

The delivery of therapeutics through the circulatory system is one of the least arduous and less invasive interventions; however, this approach is hampered by low vascular density or permeability. In this study, by exploiting the ability of monocytes to actively penetrate into diseased sites, we designed aptamer-based lipid nanovectors that actively bind onto the surface of monocytes and are released upon reaching the diseased sites. Our method was thoroughly assessed through treating two of the top causes of death in the world, cardiac ischemia-reperfusion injury and pancreatic ductal adenocarcinoma with or without liver metastasis, and showed a significant increase in survival and healing with no toxicity to the liver and kidneys in either case, indicating the success and ubiquity of our platform. We believe that this system provides a new therapeutic method, which can potentially be adapted to treat a myriad of diseases that involve monocyte recruitment in their pathophysiology.

Nanoparticles for delivery of agents to fetal lungs

Fetal treatment of congenital lung disease, such as cystic fibrosis, surfactant protein syndromes, and congenital diaphragmatic hernia, has been made possible by improvements in prenatal diagnostic and interventional technology. Delivery of therapeutic agents to fetal lungs in nanoparticles improves cellular uptake. The efficacy and safety of nanoparticle-based fetal lung therapy depends on targeting of necessary cell populations. This study aimed to determine the relative distribution of nanoparticles of a variety of compositions and sizes in the lungs of fetal mice delivered through intravenous and intra-amniotic routes. Intravenous delivery of particles was more effective than intra-amniotic delivery for epithelial, endothelial and hematopoietic cells in the fetal lung. The most effective targeting of lung tissue was with 250nm Poly-Amine-co-Ester (PACE) particles accumulating in 50% and 44% of epithelial and endothelial cells. This study demonstrated that route of delivery and particle composition impacts relative cellular uptake in fetal lung, which will inform future studies in particle-based fetal therapy.

Biohybrid Nanosystems for Cancer Treatment: Merging the Best of Two Worlds

During the last 20+ years, research into the biomedical application of nanotechnology has helped in reshaping cancer treatment. The clinical use of several passively targeted nanosystems resulted in improved quality of care for patients. However, the therapeutic efficacy of these systems is not superior to the original drugs. Moreover, despite extensive investigations into actively targeted nanocarriers, numerous barriers still remain before their successful clinical translation, including sufficient bloodstream circulation time and efficient tumor targeting. The combination of synthetic nanomaterials with biological elements (e.g., cells, cell membranes, and macromolecules) is presently the cutting-edge research in cancer nanotechnology. The features provided by the biological moieties render the particles with prolonged bloodstream circulation time and homotopic targeting to the tumor site. Moreover, cancer cell membranes serve as sources of neoantigens, useful in the formulation of nanovaccines. In this chapter, we will discuss the advantages of biohybrid nanosystems in cancer chemotherapy, immunotherapy, and combined therapy, as well as highlight their preparation methods and clinical translatability.

Nanostructured Polymeric, Liposomal and Other Materials to Control the Drug Delivery for Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of death globally, taking an estimated 17.9 million lives each year, representing one third of global mortality. As existing therapies still have limited success, due to the inability to control the biodistribution of the currently approved drugs, the quality of life of these patients is modest. The advent of nanomedicine has brought new insights in innovative treatment strategies. For this reason, several novel nanotechnologies have been developed for both targeted and prolonged delivery of therapeutics to the cardiovascular system tο minimize side effects. In this regard, nanoparticles made of natural and/or synthetic nanomaterials, like liposomes, polymers or inorganic materials, are emerging alternatives for the encapsulation of already approved drugs to control their delivery in a targeted way. Therefore, nanomedicine has attracted the attention of the scientific community as a potential platform to deliver therapeutics to the injured heart. In this review, we discuss the current types of biomaterials that have been investigated as potential therapeutic interventions for CVDs as they open up a host of possibilities for more targeted and effective therapies, as well as minimally invasive treatments.

Extracellular Vesicles: A New Frontier for Research in Acute Respiratory Distress Syndrome

Recent research on extracellular vesicles (EVs) has provided new insights into pathogenesis and potential therapeutic options for acute respiratory distress syndrome (ARDS). EVs are membrane-bound anuclear structures that carry important intercellular communication mechanisms, allowing targeted transfer of diverse biologic cargo, including protein, mRNA, and microRNA, among several different cell types. In this review, we discuss the important role EVs play in both inducing and attenuating inflammatory lung injury in ARDS as well as in sepsis, the most important clinical cause of ARDS. We discuss the translational challenges that need to be overcome before EVs can also be used as prognostic biomarkers in patients with ARDS and sepsis. We also consider how EVs may provide a platform for novel therapeutics in ARDS.

Safe and efficient magnetic resonance imaging of acute myocardial infarction with gadolinium-doped carbon dots

Aim: The magneto-fluorescent gadolinium-doped carbon dots (Gd-CDs) were developed as a cardiac MR imaging contrast agent to detect the infarcted myocardium on a myocardial ischemia/reperfusion (I/R) mice model. Materials & methods: The chemophysical features, cardiac MR imaging effect, biodistribution and biocompatibility of Gd-CDs were studied. Results: The ultrasmall size and good aqueous dispersibility endows Gd-CDs with high longitudinal relaxivity, intense fluorescence, excellent physiological stability and superior biocompatibility. More importantly, Gd-CDs preferentially target the infarcts as determined by the confocal microscopy and MR imaging on the I/R mice at the acute stage of myocardial infarction. Conclusion: Gd-CDs manifest great potential for development as an MR imaging contrast agent to facilitate accurate visualization and image-guided therapy of acute myocardial infarction.

Antitumoral Drug: Loaded Hybrid Nanocapsules Based on Chitosan with Potential Effects in Breast Cancer Therapy

Cancer remains one of the world's most devastating diseases and is responsible for more than 20% of all deaths. It is defined as uncontrolled proliferation of cells and spreads rapidly to healthy tissue. Controlled drug delivery systems offers great opportunities for the development of new non-invasive strategies for the treatment of cancers. The main advantage of these systems is their capacity to accumulate in tumors via enhanced permeability and retention effects. In the present study, an innovative hybrid drug delivery system based on nanocapsules obtained from the interfacial condensation between chitosan and poly(N-vinyl pyrrolidone-alt-itaconic anhydride) and containing both magnetic nanoparticles and an antitumoral drug was developed in order to improve the efficiency of the antitumoral treatment. Using dynamic light scattering, it was observed that the mean diameter of these hybrid nanocapsules was in the range of 43 to 142 nm. SEM confirmed their nanometric size and their well-defined spherical shape. These nanocapsules allowed the encapsulation of an increased amount of 5-fluorouracil and provided controlled drug release. In vitro studies have revealed that these drug-loaded hybrid nanocapsules were able to induce a cytostatic effect on breast carcinoma MCF-7 cell lines (Human Caucasian breast adenocarcinoma - HTB-22) comparable to that of the free drug.

Nanoparticles exhibit greater accumulation in kidney glomeruli during experimental glomerular kidney disease

Loss and dysfunction of glomerular podocytes result in increased macromolecule permeability through the glomerular filtration barrier and nephrotic syndrome. Current therapies can induce and maintain disease remission, but cause serious and chronic complications. Nanoparticle drug carriers could mitigate these side effects by delivering drugs to the kidneys more efficiently than free drug through tailoring of carrier properties. An important extrinsic factor of nanoparticle biodistribution is local pathophysiology, which may drive greater nanoparticle deposition in certain tissues. Here, we hypothesized that a "leakier" filtration barrier during glomerular kidney disease would increase nanoparticle distribution into the kidneys. We examined the effect of nanoparticle size and disease state on kidney accumulation in male BALB/c mice. The effect of size was tested using a panel of fluorescent polystyrene nanoparticles of size 20-200 nm, due to the relevance of this size range for drug delivery applications.Experimental focal segmental glomerulosclerosis was induced using an anti-podocyte antibody that causes abrupt podocyte depletion. Nanoparticles were modified with carboxymethyl-terminated poly(ethylene glycol) for stability and biocompatibility. After intravenous injection, fluorescence from nanoparticles of size 20 and 100 nm, but not 200 nm, was observed in kidney glomeruli and peritubular capillaries. During conditions of experimental focal segmental glomerulosclerosis, the number of fluorescent nanoparticle punctae in kidney glomeruli increased by 1.9-fold for 20 and 100 nm nanoparticles compared to normal conditions. These findings underscore the importance of understanding and leveraging kidney pathophysiology in engineering new, targeted drug carriers that accumulate more in diseased glomeruli to treat glomerular kidney disease.

Endocytic trafficking of polymeric clustered superparamagnetic iron oxide nanoparticles in mesenchymal stem cells

The technology of directing nanoparticles to specific locations in the body continues to be an area of great interest in a myriad of research fields. In the present study, we have developed nanoparticles and a method that allows the nanoparticles to move to specific sites by simultaneously utilizing the homing ability and magnetism of stem cells. Polymeric clustered SPIO (PCS) nanoparticles are composed of a superparamagnetic iron oxide nanoparticle (SPION) cluster core coated with poly lactic-co-glycolic acid (PLGA) and labeled with the fluorescent dye Cy5.5 for tracking. PCS is designed to be internalized by stem cells via endocytosis and then moved to the desired subcellular location through magnetism. Here, we investigated the interactions between SPIONs and mesenchymal stem cells (MSCs), including their absorption mechanism and subcellular localization. Exposure to the nanoparticles at 40 μg/mL for over 96 h did not affect cell survival or differentiation. We used a variety of endocytosis inhibitors and identified the potential cellular internalization pathway of SPIONs to be clathrin-mediated endocytosis. Antibodies to organelles were used to accumulate lysosomes through early and late endosomes. PCS at 40 μg/mL was internalized and stored without significant deleterious effects on stem cells, indicating that MSCs can act as an effective nanoparticle carrier. These findings also demonstrate the successful localization of the novel particles using magnetic attraction.