Neutrophil membrane-camouflaged nanoparticles alleviate inflammation and promote angiogenesis in ischemic myocardial injury

Immune in myocardial ischemia/reperfusion injury: potential mechanisms and therapeutic strategies

Myocardial infarction (MI), which is characterized by high morbidity and mortality, is a serious threat to human life and health, and timely reperfusion therapy to save ischemic myocardium is currently the most effective intervention. Although reperfusion therapy effectively restores coronary blood flow and maximally limits the infarct size, it triggers additional cell death and tissue damage, which is known as myocardial ischemia/reperfusion injury (MIRI). Multiple immune cells are present in the reperfusion area, executing specific functions and engaging in crosstalk during diverse stages, constituting a complex immune microenvironment involved in tissue repair and regeneration after MIRI. Immunotherapy brings new hope for treating ischemic heart disease by modulating the immune microenvironment. In this paper, we explore the regulatory roles of various immune cells during MIRI and the close relationship between different cell deaths and the immune microenvironment. In addition, we present the current status of research on targeting the immune system to intervene in MIRI, with the expectation of providing a basis for achieving clinical translation.

Physically engineered extracellular vesicles targeted delivering miR-21-5p to promote renoprotection after renal ischemia-reperfusion injury

Acute kidney injury (AKI) resulting from ischemia-reperfusion injury (IRI) is a common challenge in various clinical practices, yet effective therapies remain elusive. Endothelial injury plays a crucial role in the pathogenesis of renal IRI. Endothelial progenitor cells (EPCs) derived extracellular vesicles (EVs) hold promise as cell-free therapies for treating renal IRI; however, their efficacy is limited by low delivery efficiency. In this study, we developed neutrophils (NEs) membrane-modified EVs (N-EVs) by exploiting the natural properties of NEs to target damaged endothelium. N-EVs inherited the characteristic membrane proteins of NEs along with the biological functions of EPCs-EVs. Results from in vitro and in vivo experiments demonstrated that N-EVs significantly enhanced the targeting efficiency of EVs towards IRI kidneys via P-selectin glycoprotein ligand-1 (PSGL-1). Moreover, N-EVs effectively promoted the proliferation, migration, and tube-formation abilities of injured endothelial cells (ECs) and contributed to overall renal function improvement in IRI kidneys through targeted delivery of miR-21-5p. Additionally, N-EVs could restore damaged endothelial integrity, reduce cytokine release, and inhibit leukocyte infiltration, hence alleviating renal inflammation. In conclusion, our accessible engineering approach represents a promising strategy for treating renal IRI. Furthermore, this membrane hybrid modification can be tailored and optimized for broader applications in treating other diseases.

Neutrophil membrane-coated multifunctional biomimetic nanoparticles for spinal cord injuries

Spinal cord injury (SCI) is one of the most complex diseases. After SCI, severe secondary injuries can cause intense inflammatory storms and oxidative stress responses, leading to extensive neuronal apoptosis. Effective regulation of inflammation and oxidative stress after SCI remains an unresolved challenge. In this study, resveratrol-loaded nanoparticles coated with neutrophil membranes (NMR) were prepared using the emulsion-solvent evaporation method and membrane encapsulation technology. Multifunctional biomimetic nanoparticles retain neutrophil membrane-related receptors and possess a strong adsorption capacity for inflammatory factors. As a drug carrier, NMR can sustainably release resveratrol for >72 h. Moreover, co-culture studies in vitro show that the NMR help regulate macrophage polarization to relieve inflammatory response, reduce intracellular reactive oxygen species by approximately 50%, and improve mitochondrial membrane potential to alleviate oxidative stress. After injecting NMR into the injury site, it reduces early apoptosis, inhibit scar formation, and promote neural network recovery to improve motor function. This study demonstrates the anti-inflammatory, antioxidant, and neuroprotective effects of NMR, thus providing a novel therapeutic strategy for SCI.

Enhanced FGF21 Delivery via Neutrophil-Membrane-Coated Nanoparticles Improves Therapeutic Efficacy for Myocardial Ischemia-Reperfusion Injury

Acute myocardial infarction, a leading cause of death globally, is often associated with cardiometabolic disorders such as atherosclerosis and metabolic syndrome. Metabolic treatment of these disorders can improve cardiac outcomes, as exemplified by the GLP-1 agonist semaglutide. Fibroblast growth factor 21 (FGF21), a novel metabolic regulator, plays pivotal roles in lipid mobilization and energy conversion, reducing lipotoxicity, inflammation, mitochondrial health, and subsequent tissue damage in organs such as the liver, pancreas, and heart. Here, we test the therapeutic efficacy of FGF21 in mice with ischemia-reperfusion (I/R) injury, a model of acute myocardial infarction. We employed the strategic method of coating the FGF21-encapsulating liposomal nanoparticles with a neutrophil membrane designed to camouflage FGF21 from macrophage-mediated efferocytotic clearance and promote its targeted accumulation at I/R foci due to the inherent neutrophilic attraction to the inflammatory site. Our findings revealed that the coated FGF21 nanoparticles markedly accumulated within the lesions with a prolonged half-life, in additional to the liver, leading to substantial improvements in cardiac performance by enhancing mitochondrial energetic function and reducing oxidative stress, inflammation, and cell death. Therefore, our research highlights a viable strategy for the enhanced delivery of therapeutical FGF21 analogs to lesions beyond the liver following myocardial infarction.

Combined Strategies for Nanodrugs Noninvasively Overcoming the Blood-Brain Barrier and Actively Targeting Glioma Lesions

Drugs for tumor treatment face various challenges, including poor solubility, poor stability, short blood half-life, nontargeting ability, and strong toxic side effects. Fortunately, nanodrug delivery systems provide excellent solution to these problems. However, nanodrugs for glioma treatment also face some key challenges including overcoming the blood-brain barrier (BBB) and, specifically, accumulation in glioma lesions. In this review, we systematically summarize the advantages and disadvantages of combined strategies for nanodrugs noninvasively overcoming BBB and actively targeting glioma lesions to achieve effective glioma therapy. Common noninvasive strategies for nanodrugs overcoming the BBB include bypassing the BBB via the nose-to-brain route, opening the tight junction of the BBB by focused ultrasound with microbubbles, and transendothelial cell transport by intact cell loading, ligand decoration, or cell membrane camouflage of nanodrugs. Actively targeting glioma lesions after overcoming the BBB is another key factor helping nanodrugs accurately treat in situ gliomas. This aim can also be achieved by loading nanodrugs into intact cells and modifying ligand or cell membrane fragments on the surface of nanodrugs. Targeting decorated nanodrugs can guarantee precise glioma killing and avoid side effects on normal brain tissues that contribute to the specific recognition of glioma lesions. Furthermore, the challenges and prospects of nanodrugs in clinical glioma treatment are discussed.

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.

Black phosphorus nanoplatform coated with platelet membrane improves inhibition of atherosclerosis progression through macrophage targeting and efferocytosis

Plaque rupture in atherosclerosis (AS) is a major cause of acute cardiovascular events. Macrophage-induced inflammatory responses and accumulation of excess reactive oxygen species (ROS) primarily induce unstable plaques. Therefore, targeting ROS clearance and functional modulation of macrophages are clinically crucial for improving plaque stability and inhibiting AS progression. Here, we constructed a bionic nano-delivery platform, PBP@siR@PM, using platelet membranes (PM) coated with black phosphorus nanosheets (BPNSs) to target macrophages in atherosclerotic plaques. Meanwhile, PM-coated BPNSs (PBP@siR@PM) were used to deliver small interfering RNA silencing Ca2+/calmodulin-dependent protein kinase γ (CaMKIIγ) into macrophages. Furthermore, macrophage efferocytosis was restored by inhibiting CaMKIIγ and increasing the expression of MerTK, a cytosolic receptor, thus promoting the clearance of apoptotic cells from plaques. This study demonstrated that intraplaque macrophage-targeted therapy using the bionic nano-delivery platform PBP@siR@PM effectively removed excess ROS from macrophages, promoted efferocytosis, cleared apoptotic cells in plaques, improved plaque stability, and largely inhibited AS progression in ApoE-/- mice after high fat diet. In summary, this study proposes a therapeutic strategy for AS and highlights the outstanding therapeutic potential of biomimetic nanomaterials in this type of chronic inflammatory disease. STATEMENT OF SIGNIFICANCE: Rupture of atherosclerotic unstable plaques is a major cause of acute cardiovascular events. Macrophage-induced chronic inflammation and oxidative stress due to overloaded ROS are major contributors to plaque rupture. In this study, we focused on the improvement of macrophage efferocytosis within the plaque for the effective treatment of atherosclerosis. A bionic nano-delivery platform was constructed using platelet membranes (PM) coated black phosphorus nanosheets (BPNSs) to target macrophages in atherosclerotic plaques. In conclusion, intraplaque macrophage-targeted therapy based on the bionic nano-delivery platform PBP@siR@PM effectively scavenges overloaded ROS in macrophages, promotes efferocytosis, removes apoptotic cells from plaques, and improves plaque stability, which significantly inhibits the progression of atherosclerosis in ApoE-/- mice after a high-fat diet.

Comprehensive macro and micro views on immune cells in ischemic heart disease

Ischemic heart disease (IHD) is a prevalent cardiovascular condition that remains the primary cause of death due to its adverse ventricular remodelling and pathological changes in end-stage heart failure. As a complex pathologic condition, it involves intricate regulatory processes at the cellular and molecular levels. The immune system and cardiovascular system are closely interconnected, with immune cells playing a crucial role in maintaining cardiac health and influencing disease progression. Consequently, alterations in the cardiac microenvironment are influenced and controlled by various immune cells, such as macrophages, neutrophils, dendritic cells, eosinophils, and T-lymphocytes, along with the cytokines they produce. Furthermore, studies have revealed that Gata6+ pericardial cavity macrophages play a key role in regulating immune cell migration and subsequent myocardial tissue repair post IHD onset. This review outlines the role of immune cells in orchestrating inflammatory responses and facilitating myocardial repair following IHD, considering both macro and micro views. It also discusses innovative immune cell-based therapeutic strategies, offering new insights for further research on the pathophysiology of ischemic heart disease and immune cell-targeted therapy for IHD.

Comprehensive macro and micro views on immune cells in ischemic heart disease

Ischemic heart disease (IHD) is a prevalent cardiovascular condition that remains the primary cause of death due to its adverse ventricular remodelling and pathological changes in end‐stage heart failure. As a complex pathologic condition, it involves intricate regulatory processes at the cellular and molecular levels. The immune system and cardiovascular system are closely interconnected, with immune cells playing a crucial role in maintaining cardiac health and influencing disease progression. Consequently, alterations in the cardiac microenvironment are influenced and controlled by various immune cells, such as macrophages, neutrophils, dendritic cells, eosinophils, and T‐lymphocytes, along with the cytokines they produce. Furthermore, studies have revealed that Gata6+ pericardial cavity macrophages play a key role in regulating immune cell migration and subsequent myocardial tissue repair post IHD onset. This review outlines the role of immune cells in orchestrating inflammatory responses and facilitating myocardial repair following IHD, considering both macro and micro views. It also discusses innovative immune cell‐based therapeutic strategies, offering new insights for further research on the pathophysiology of ischemic heart disease and immune cell‐targeted therapy for IHD.

Engineered Macrophage Membrane-Coated S100A9-siRNA for Ameliorating Myocardial Ischemia-Reperfusion Injury

Despite the widespread adoption of emergency coronary reperfusion therapy, reperfusion-induced myocardial injury remains a challenging issue in clinical practice. Following myocardial reperfusion, S100A8/A9 molecules are considered pivotal in initiating and regulating tissue inflammatory damage. Effectively reducing the S100A8/A9 level in ischemic myocardial tissue holds significant therapeutic value in salvaging damaged myocardium. In this study, HA (hemagglutinin)- and RAGE (receptor for advanced glycation end products)- comodified macrophage membrane-coated siRNA nanoparticles (MMM/RNA NPs) with siRNA targeting S100A9 (S100A9-siRNA) are successfully prepared. This nanocarrier system is able to target effectively the injured myocardium in an inflammatory environment while evading digestive damage by lysosomes. In vivo, migration of MMM/RNA NPs to myocardial injury lesions is confirmed in a myocardial ischemia-reperfusion injury (MIRI) mouse model. Intravenous injection of MMM/RNA NPs significantly reduced S100A9 levels in serum and myocardial tissues, further decreasing myocardial infarction area and improving cardiac function. Targeted reduction of S100A8/A9 by genetically modified macrophage membrane-coated nanoparticles may represent a new therapeutic intervention for MIRI.

Enhancing Cardioprotection Through Neutrophil-Mediated Delivery of 18β-Glycyrrhetinic Acid in Myocardial Ischemia/Reperfusion Injury

Myocardial ischemia/reperfusion injury (MI/RI) generates reactive oxygen species (ROS) and initiates inflammatory responses. Traditional therapies targeting specific cytokines or ROS often prove inadequate. An innovative drug delivery system (DDS) is developed using neutrophil decoys (NDs) that encapsulate 18β-glycyrrhetinic acid (GA) within a hydrolyzable oxalate polymer (HOP) and neutrophil membrane vesicles (NMVs). These NDs are responsive to hydrogen peroxide (H2O2), enabling controlled GA release. Additionally, NDs adsorb inflammatory factors, thereby reducing inflammation. They exhibit enhanced adhesion to inflamed endothelial cells (ECs) and improved penetration. Once internalized by cardiomyocytes through clathrin-mediated endocytosis, NDs protect against ROS-induced damage and inhibit HMGB1 translocation. In vivo studies show that NDs preferentially accumulate in injured myocardium, reducing infarct size, mitigating adverse remodeling, and enhancing cardiac function, all while maintaining favorable biosafety profiles. This neutrophil-based system offers a promising targeted therapy for MI/RI by addressing both inflammation and ROS, holding potential for future clinical applications.

Developing Cell-Membrane-Associated Liposomes for Liver Diseases

Over the past decade, a marked escalation in the prevalence of hepatic pathologies has been observed, adversely impacting the quality of life for many. The predominant therapeutic strategy for liver diseases has been pharmacological intervention; however, its efficacy is often constrained. Currently, liposomes are tiny structures that can deliver drugs directly to targeted areas, enhancing their effectiveness. Specifically, cell membrane-associated liposomes have gained significant attention. Despite this, there is still much to learn about the binding mechanism of this type of liposome. Thus, this review comprehensively summarizes relevant information on cell membrane-associated liposomes, including their clinical applications and future development directions. First, we will briefly introduce the composition and types of cell membrane-associated liposomes. We will provide an overview of their structure and discuss the various types of liposomes associated with cell membranes. Second, we will thoroughly discuss various strategies of drug delivery using these liposomes. Lastly, we will discuss the application and clinical challenges associated with using cell membrane-associated liposomes in treating liver diseases. We will explore their potential benefits while also addressing the obstacles that need to be overcome. Furthermore, we will provide prospects for future development in this field. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization.

Artificial Neutrophil-Mediated CEBPA-saRNA Delivery to Ameliorate ALI/ARDS

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS) still faces great challenges due to uncontrollable inflammation disorders, complicated causes of occurrence, and high mortality. Small-activating RNA (saRNA) has emerged as a novel and powerful gene-activating tool that may be useful in the treatment of ALI/ARDS. However, effective saRNA therapy is still challenged by the lack of effective and safe gene delivery vehicles. In this study, we develop a type of artificial neutrophil that is used to deliver saRNAs for ALI/ARDS treatment. The saRNA targeting CCAAT-enhancer binding protein α (CEBPA-saRNA) is complexed with H1 histone and further camouflaged with neutrophil membranes (NHR). Interestingly, we are the first to find that the H1 histone possesses the most effective binding capability to saRNA, compared to other subtypes. The prepared NHR shows excellent physicochemical properties, effective cellular uptake by the inflammatory M1 macrophages, and efficient activation of CEBPA, leading to significant M2 polarization. NHR shows an extended circulation lifetime and high-level accumulation in the inflamed lungs. The in vivo experiments indicate that NHR ameliorates ALI in a mouse model. This type of artificial neutrophil shows powerful inflammatory inhibition both in vitro and in vivo, which opens a new avenue for the treatment of ALI/ARDS.

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.

Inflammation and Acinar Cell Dual-Targeting Nanomedicines for Synergistic Treatment of Acute Pancreatitis via Ca2+ Homeostasis Regulation and Pancreas Autodigestion Inhibition

Severe acute pancreatitis (AP) is a life-threatening pancreatic inflammatory disease with a high mortality rate (∼40%). Existing pharmaceutical therapies in development or in clinical trials showed insufficient treatment efficacy due to their single molecular therapeutic target, poor water solubility, short half-life, limited pancreas-targeting specificity, etc. Herein, acid-responsive hollow mesoporous Prussian blue nanoparticles wrapped with neutrophil membranes and surface modified with the N,N-dimethyl-1,3-propanediamine moiety were developed for codelivering membrane-permeable calcium chelator BAPTA-AM (BA) and trypsin activity inhibitor gabexate mesylate (Ga). In the AP mouse model, the formulation exhibited efficient recruitment at the inflammatory endothelium, trans-endothelial migration, and precise acinar cell targeting, resulting in rapid pancreatic localization and higher accumulation. A single low dose of the formulation (BA: 200 μg kg-1, Ga: 0.75 mg kg-1) significantly reduced pancreas function indicators to close to normal levels at 24 h, effectively restored the cell redox status, reduced apoptotic cell proportion, and blocked the systemic inflammatory amplified cascade, resulting in a dramatic increase in the survival rate from 58.3 to even 100%. Mechanistically, the formulation inhibited endoplasmic reticulum stress (IRE1/XBP1 and ATF4/CHOP axis) and restored impaired autophagy (Beclin-1/p62/LC3 axis), thereby preserving dying acinar cells and restoring the cellular "health status". This formulation provides an upstream therapeutic strategy with clinical translation prospects for AP management through synergistic ion homeostasis regulation and pancreatic autodigestion inhibition.

Convergence of nanomedicine and neutrophils for drug delivery

Neutrophils have recently emerged as promising carriers for drug delivery due to their unique properties including rapid response toward inflammation, chemotaxis, and transmigration. When integrated with nanotechnology that has enormous advantages in improving treatment efficacy and reducing side effects, neutrophil-based nano-drug delivery systems have expanded the repertoire of nanoparticles employed in precise therapeutic interventions by either coating nanoparticles with their membranes, loading nanoparticles inside living cells, or engineering chimeric antigen receptor (CAR)-neutrophils. These neutrophil-inspired therapies have shown superior biocompatibility, targeting ability, and therapeutic robustness. In this review, we summarized the benefits of combining neutrophils and nanotechnologies, the design principles and underlying mechanisms, and various applications in disease treatments. The challenges and prospects for neutrophil-based drug delivery systems were also discussed.

Neutrophil-Mimetic, ROS Responsive, and Oxygen Generating Nanovesicles for Targeted Interventions of Refractory Rheumatoid Arthritis

Rheumatoid arthritis (RA) is the most prevalent inflammatory joint disease worldwide, leading to irreversible disability and even mortality. Unfortunately, current treatment regimens fail to cure RA due to low therapeutic responses and off-target side effects. Herein, a neutrophil membrane-cloaked, natural anti-arthritic agent leonurine (Leo), and catalase (CAT) co-loaded nanoliposomal system (Leo@CAT@NM-Lipo) is constructed to remodel the hostile microenvironment for RA remission. Due to the inflammation tropism inherited from neutrophils, Leo@CAT@NM-Lipo can target and accumulate in the inflamed joint cavity where high-level ROS can be catalyzed into oxygen by CAT to simultaneously accelerate the drug release and alleviate hypoxia at the lesion site. Besides, the neutrophil membrane camouflaging also enhances the anti-inflammatory potentials of Leo@CAT@NM-Lipo by robustly absorbing pro-arthritogenic cytokines and chemokines. Consequently, Leo@CAT@NM-Lipo successfully alleviated paw swelling, reduced arthritis score, mitigated bone and cartilage damage, and reversed multiple organ dysfunctions in adjuvant-induced arthritis rats (AIA) rats by synergistic effects of macrophage polarization, inflammation resolution, ROS scavenging, and hypoxia relief. Furthermore, Leo@CAT@NM-Lipo manifested excellent biocompatibility both at the cellular and animal levels. Taken together, the study provided a neutrophil-mimetic and ROS responsive nanoplatform for targeted RA therapy and represented a promising paradigm for the treatment of a variety of inflammation-dominated diseases.

Biomimetic nanomaterials in myocardial infarction treatment: Harnessing bionic strategies for advanced therapeutics

Myocardial infarction (MI) and its associated poor prognosis pose significant risks to human health. Nanomaterials hold great potential for the treatment of MI due to their targeted and controlled release properties, particularly biomimetic nanomaterials. The utilization of biomimetic strategies based on extracellular vesicles (EVs) and cell membranes will serve as the guiding principle for the development of nanomaterial therapy in the future. In this review, we present an overview of research progress on various exosomes derived from mesenchymal stem cells, cardiomyocytes, or induced pluripotent stem cells in the context of myocardial infarction (MI) therapy. These exosomes, utilized as cell-free therapies, have demonstrated the ability to enhance the efficacy of reducing the size of the infarcted area and preventing ischaemic reperfusion through mechanisms such as oxidative stress reduction, polarization modulation, fibrosis inhibition, and angiogenesis promotion. Moreover, EVs can exert cardioprotective effects by encapsulating therapeutic agents and can be engineered to specifically target the infarcted myocardium. Furthermore, we discuss the use of cell membranes derived from erythrocytes, stem cells, immune cells and platelets to encapsulate nanomaterials. This approach allows the nanomaterials to camouflage themselves as endogenous substances targeting the region affected by MI, thereby minimizing toxicity and improving biocompatibility. In conclusion, biomimetic nano-delivery systems hold promise as a potentially beneficial technology for MI treatment. This review serves as a valuable reference for the application of biomimetic nanomaterials in MI therapy and aims to expedite the translation of NPs-based MI therapeutic strategies into practical clinical applications.

cFLIPL alleviates myocardial ischemia-reperfusion injury by regulating pyroptosis

Alleviating myocardial ischemia-reperfusion injury (MIRI) plays a critical role in the prognosis and improvement of cardiac function following acute myocardial infarction. Pyroptosis is a newly identified form of cell death that has been implicated in the regulation of MIRI. In our study, H9c2 cells and SD rats were transfected using a recombinant adenovirus vector carrying cFLIPL , and the transfection was conducted for 3 days. Subsequently, H9c2 cells were subjected to 4 h of hypoxia followed by 12 h of reoxygenation to simulate an in vitro ischemia-reperfusion model. SD rats underwent 30 min of ischemia followed by 2 h of reperfusion to establish an MIRI model. Our findings revealed a notable decrease in cFLIPL expression in response to ischemia/reperfusion (I/R) and hypoxia/reoxygenation (H/R) injuries. Overexpression of cFLIPL can inhibit pyroptosis, reducing myocardial infarction area in vivo, and enhancing H9c2 cell viability in vitro. I/R and H/R injuries induced the upregulation of ASC, cleaved Caspase 1, NLRP3, GSDMD-N, IL-1β, and IL-18 proteins, promoting cell apoptosis. Our research indicates that cFLIPL may suppress pyroptosis by strategically binding with Caspase 1, inhibiting the release of inflammatory cytokines and preventing cell membrane rupture. Therefore, cFLIPL could potentially serve as a promising target for alleviating MIRI by suppressing the pyroptotic pathway.

Cell or cell derivative-laden hydrogels for myocardial infarction therapy: from the perspective of cell types

Myocardial infarction (MI) is a global cardiovascular disease with high mortality and morbidity. To treat acute MI, various therapeutic approaches have been developed, including cells, extracellular vesicles, and biomimetic nanoparticles. However, the clinical application of these therapies is limited due to low cell viability, inadequate targetability, and rapid elimination from cardiac sites. Injectable hydrogels, with their three-dimensional porous structure, can maintain the biomechanical stabilization of hearts and the transplantation activity of cells. However, they cannot regenerate cardiomyocytes or repair broken hearts. A better understanding of the collaborative relationship between hydrogel delivery systems and cell or cell-inspired therapy will facilitate advancing innovative therapeutic strategies against MI. Following that, from the perspective of cell types, MI progression and recent studies on using hydrogel to deliver cell or cell-derived preparations for MI treatment are discussed. Finally, current challenges and future prospects of cell or cell derivative-laden hydrogels for MI therapy are proposed.

CCR2 inhibitor strengthens the adiponectin effects against myocardial injury after infarction

Little evidence demonstrated the effects of nitric oxide (NO) hydrogel with adipocytes in vivo. We aimed to investigate the effects of adiponectin (ADPN) and CCR2 antagonist on cardiac functions and macrophage phenotypes after myocardial infarction (MI) using chitosan caged nitric oxide donor (CSNO) patch with adipocytes. 3T3-L1 cell line was induced to adipocytes and ADPN expression was knocked down. CSNO was synthesized and patch was constructed. MI model was constructed and patch was placed on the infarcted area. ADPN knockdown adipocytes or control was incubated with CSNO patch, and CCR2 antagonist was also used to investigate the ADPN effects on myocardial injury after infarction. On day 7 after operation, cardiac functions of the mice using CSNO with adipocytes or ADPN knockdown adipocytes improved more than in mice only using CSNO for treatment. Lymphangiogenesis increased much more in the MI mice using CSNO with adipocytes. After treating with CCR2 antagonist, Connexin43+ CD206+ cells and ZO-1+ CD206+ cells increased, suggesting that CCR2 antagonist promoted M2 polarization after MI. Besides, CCR2 antagonist promoted ADPN expression in adipocytes and cardiomyocytes. ELISA was also used and CKMB expression was much lower than other groups at 3 days after operation. On day 7 after operation, the VEGF and TGFβ expressions were high in the adipocytes CSNO group, illustrating that higher ADPN led to better treatment. In all, CCR2 antagonist enhanced the ADPN effects on macrophage M2 polarization and cardiac functions. The combination used in border zone and infarcted areas may help improve patients' prognosis in surgery, such as CABG.

Lesion-specific suppression of YAP/TAZ by biomimetic nanodrug ameliorates atherosclerosis development

Atherosclerosis, characterized by the buildup of lipid-rich plaque on the vessel wall, is the primary cause of myocardial infarction and ischemic stroke. Recent studies have demonstrated that dysregulation of yes-associated protein 1 (YAP) and transcriptional coactivator with PDZ-binding domain (TAZ) contributes to plaque development, making YAP/TAZ potential therapeutic targets. However, systemic modulation of YAP/TAZ expression or activities risks serious off-target effects, limiting clinical applicability. To address the challenge, this study develops monocyte membrane-coated nanoparticles (MoNP) as a drug delivery vehicle targeting activated endothelium lining the plaque surface and utilizes MoNP to deliver verteporfin (VP), a potent YAP/TAZ inhibitor, for lesion-specific treatment of atherosclerosis. The results reveal that MoNP significantly enhance payload delivery to inflamed endothelial cells (EC) while avoiding phagocytic cells, and preferentially accumulate in atherosclerotic regions. MoNP-mediated delivery of VP substantially reduces YAP/TAZ expression, suppressing inflammatory gene expression and macrophage infiltration in cultured EC and mouse arteries exposed to atherogenic stimuli. Importantly, this lesion-targeted VP nanodrug effectively decreases plaque development in mice without causing noticeable histopathological changes in major organs. Collectively, these findings demonstrate a plaque-targeted and pathway-specific biomimetic nanodrug, potentially leading to safer and more effective treatments for atherosclerosis.