Stem cells derived exosomes and biomaterials to modulate autophagy and mend broken hearts

Scalable technologies in the manufacture and deployment of cell-free cardiac therapies

Despite demonstrated therapeutic potential, cell-based cardiac therapies face substantial manufacturing, practical, and biological limitations which constrain their clinical translation. We examine selected emerging acellular approaches that could overcome these limitations while maintaining therapeutic efficacy. Biomaterial engineering has enabled the creation of acellular scaffolds from natural and synthetic sources that provide mechanical support and deliver bioactive signals to the injured heart. As an alternative, platelet-derived extracellular vesicles (EVs) can carry complex bioactive cargoes which can act on multiple therapeutic pathways while leveraging existing blood-banking infrastructure. Lastly, synthetic fabricated nanocarriers can form controlled release systems for therapeutic factor delivery. We describe how these three simplified therapeutic approaches can address key requirements including achieving commercial scale manufacturability and biological efficacy to enable broader therapeutic deployment.

Exploring the landscape of exosomes in heart failure: a bibliometric analysis

BACKGROUND

Exosomes, which carry bioactive RNAs, proteins, lipids, and metabolites, have emerged as novel diagnostic markers and therapeutic agents for heart failure (HF). This study aims to elucidate the trends, key contributors, and research hotspots of exosomes in HF.

METHODS

We collected publications related to exosomes in HF from the Web of Science Core Collection. Using VOSviewer, CiteSpace, Excel, and SRplot software, we performed a visualization analysis of authors, countries, institutions, keywords, and references.

RESULTS

The publications on exosomes in the field of HF has grown rapidly. China ( N = 245, 42.683%) and the United States ( N = 170, 29.617%) are the leading contributors in this area. Wang L ( N = 14, 2.443%) is the most prolific author in the field. Key areas of exosome research in HF include mesenchymal stem cells (MSCs), angiogenesis, and microRNAs. Additionally, keywords and references analysis reveal that exosome research in HF is primarily focused on the role of exosomes in intercellular communication in HF, the value of miRNAs in exosomes as diagnostic markers, and the therapeutic mechanisms of MSC-derived exosomes.

CONCLUSION

Exosomes are receiving increasing attention in the field of HF. Mapping the development landscape of exosomes in HF will help researchers accelerate progress in this area.

Clinical translation of mesenchymal stem cells in ischemic heart failure: Challenges and future perspectives

Myocardial infarction (MI) with resulting congestive heart failure is one of the leading causes of death worldwide. Current therapies for treating MI, such as devices, traditional medicine, and surgeries, come with many limitations as patients in their final stages of heart failure have little chances of experiencing any reversible changes. In recent decades, Mesenchymal stem cell (MSC) based therapy has become one of the most popular and rapidly developing fields in treating MI. Their supremacy for clinical applications is partially due to their unique properties and encouraging pre-clinical outcomes in various animal disease models. However, the majority of clinical trials registered for MSC therapy for diverse human diseases, including MI, have fallen short of expectations. This review intends to discuss the recent advances in the clinical application of using MSCs for cardiac repair and discuss challenges facing the clinical translation of MSCs for cardiac regeneration such as restoration of endothelial-cardiomyocyte crosstalk, immunomodulation and immune rejection, poor homing and migration, as well as low retention and survival. Furthermore, we will discuss recent strategies being investigated to help overcome some of these challenges.

Cardiac preservation using ex vivo organ perfusion: new therapies for the treatment of heart failure by harnessing the power of growth factors using BMP mimetics like THR-184

As heart transplantation continues to be the gold standard therapy for end-stage heart failure, the imbalance between the supply of hearts, and the demand for them, continues to get worse. In the US alone, with less than 4,000 hearts suitable for transplant and over 100,000 potential recipients, this therapy is only available to a very few. The use of hearts Donated after Circulatory Death (DCD) and Donation after Brain Death (DBD) using ex vivo machine perfusion (EVMP) is a promising approach that has already increased the availability of suitable organs for heart transplantation. EVMP offers the promise of enabling the expansion of the overall number of heart transplants and lower rates of early graft dysfunction. These are realized through (1) safe extension of the time between procurement and transplantation and (2) ex vivo assessment of preserved hearts. Notably, ex vivo perfusion has facilitated the donation of DCD hearts and improved the success of transplantation. Nevertheless, DCD hearts suffer from serious preharvest ischemia/reperfusion injury (IRI). Despite these developments, only 40% of hearts offered for transplantation can be utilized. These devices do offer an opportunity to evaluate donor hearts for transplantation, resuscitate organs previously deemed unsuitable for transplantation, and provide a platform for the development of novel therapeutics to limit cardiac injury. Bone Morphogenetic Protein (BMP) signaling is a new target which holds the potential for ameliorating myocardial IRI. Recent studies have demonstrated that BMP signaling has a significant role in blocking the deleterious effects of injury to the heart. We have designed novel small peptide BMP mimetics that act via activin receptor-like kinase (ALK3), a type I BMP receptor. They are capable of (1) inhibiting inflammation and apoptosis, (2) blocking/reversing the epithelial-mesenchymal transition (EMT) and fibrosis, and (3) promoting tissue regeneration. In this review, we explore the promise that novel therapeutics, including these BMP mimetics, offer for the protection of hearts against myocardial injury during ex vivo transportation for cardiac transplantation. This protection represents a significant advance and a promising ex vivo therapeutic approach to expanding the donor pool by increasing the number of transplantable hearts.

Bidirectional modulation of extracellular vesicle-autophagy axis in acute lung injury: Molecular mechanisms and therapeutic implications

Acute lung injury (ALI), a multifactorial pathological condition, manifests through heightened inflammatory responses, compromised lung epithelial-endothelial barrier function, and oxidative stress, potentially culminating in respiratory failure and mortality. This study explores the intricate interplay between two crucial cellular mechanisms-extracellular vesicles (EVs) and autophagy-in the context of ALI pathogenesis and potential therapeutic interventions.EVs, bioactive membrane-bound structures secreted by cells, serve as versatile carriers of molecular cargo, facilitating intercellular communication and significantly influencing disease progression. Concurrently, autophagy, an essential intracellular degradation process, maintains cellular homeostasis and has emerged as a promising therapeutic target in ALI and acute respiratory distress syndrome.Our research unveils a fascinating "EV-Autophagy dual-drive pathway," characterized by reciprocal regulation between these two processes. EVs modulate autophagy activation and inhibition, while autophagy influences EV production, creating a dynamic feedback loop. This study posits that precise manipulation of this pathway could revolutionize ALI treatment strategies.By elucidating the mechanisms underlying this cellular crosstalk, we open new avenues for targeted therapies. The potential for engineered EVs to fine-tune autophagy in ALI treatment is explored, alongside innovative concepts such as EV-based vaccines for ALI prevention and management. This research not only deepens our understanding of ALI pathophysiology but also paves the way for novel, more effective therapeutic approaches in critical care medicine.

Delivery of neurotrophin-3 by RVG-Lamp2b-modified mesenchymal stem cell-derived exosomes alleviates facial nerve injury

We aim to investigate the effect of RVG-Lamp2b-modified exosomes (exos) loaded with neurotrophin-3 (NT-3) on facial nerve injury. Exos were collected from control cells (Ctrl Exo) or bone marrow mesenchymal stem cells co-transfected with RVG-Lamp2b and NT-3 plasmids (RVG-NT-3 Exo) by gradient centrifugation and identified by western blotting, transmission electron microscopy, and nanoparticle tracking analysis. Effect of RVG-NT-3 Exo on oxidative stress damage was determined by analysis of the morphology, viability, and ROS production of neurons. Effect of RVG-NT-3 Exo on facial nerve axotomy (FNA) was determined by detecting ROS production, neuroinflammatory reaction, microglia activation, facial motor neuron (FMN) death, and myelin sheath repair. Loading NT-3 and modifying with RVG-Lamp2b did not alter the properties of the exos. Moreover, RVG-NT-3 Exo could effectively target neurons to deliver NT-3. Treatment with RVG-NT-3 Exo lowered H2O2-induced oxidative stress damage in primary neurons and Nsc-34 cells. RVG-NT-3 Exo treatment significantly decreased ROS production, neuroinflammatory response, FMN death, and elevated microglia activation and myelin sheath repair in FNA rat models. Our findings suggested that RVG-NT-3 Exo-mediated delivery of NT-3 is effective for the treatment of facial nerve injury.

Extracellular vesicles in nanomedicine and regenerative medicine: A review over the last decade

Small extracellular vesicles (sEVs) are known to be secreted by a vast majority of cells. These sEVs, specifically exosomes, induce specific cell-to-cell interactions and can activate signaling pathways in recipient cells through fusion or interaction. These nanovesicles possess several desirable properties, making them ideal for regenerative medicine and nanomedicine applications. These properties include exceptional stability, biocompatibility, wide biodistribution, and minimal immunogenicity. However, the practical utilization of sEVs, particularly in clinical settings and at a large scale, is hindered by the expensive procedures required for their isolation, limited circulation lifetime, and suboptimal targeting capacity. Despite these challenges, sEVs have demonstrated a remarkable ability to accommodate various cargoes and have found extensive applications in the biomedical sciences. To overcome the limitations of sEVs and broaden their potential applications, researchers should strive to deepen their understanding of current isolation, loading, and characterization techniques. Additionally, acquiring fundamental knowledge about sEVs origins and employing state-of-the-art methodologies in nanomedicine and regenerative medicine can expand the sEVs research scope. This review provides a comprehensive overview of state-of-the-art exosome-based strategies in diverse nanomedicine domains, encompassing cancer therapy, immunotherapy, and biomarker applications. Furthermore, we emphasize the immense potential of exosomes in regenerative medicine.

Stem cell therapy for cardiac regeneration: past, present, and future

Cardiac disorders remain the leading cause of mortality worldwide. Current clinical strategies, including drug therapy, surgical interventions, and organ transplantation offer limited benefits to patients without regenerating the damaged myocardium. Over the past decade, stem cell therapy has generated a keen interest owing to its unique self-renewal and immune privileged characteristics. Furthermore, the ability of stem cells to differentiate into specialized cell types, has made them a popular therapeutic tool against various diseases. This comprehensive review provides an overview of therapeutic potential of different types of stem cells in reference to cardiovascular diseases. Furthermore, it sheds light on the advantages and limitations associated with each cell type. An in-depth analysis of the challenges associated with stem cell research and the hurdles for its clinical translation and their possible solutions have also been elaborated upon. It examines the controversies surrounding embryonic stem cells and the emergence of alternative approaches, such as the use of induced pluripotent stem cells for cardiac therapeutic applications. Overall, this review serves as a valuable resource for researchers, clinicians, and policymakers involved in the field of regenerative medicine, guiding the development of safe and effective stem cell-based therapies to revolutionize patient care.