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

Tissue engineering with targeted delivery of nanotized S-nitrosyl mutant of NEMO ameliorates myocardial infarction

BACKGROUND

Myocardial infarction (MI) is characterized by an elevated nitrosative and hypoxic microenvironment due to reduced coronary blood flow. NEMO (IKKγ) regulates the formation of the IKK holo-complex to activate NFκB-p65 signaling. This study reports successful restoration of MI through cardiomyocyte-targeted nanotized S-nitrosyl mutant of NEMO under elevated nitrosative stress.

METHODS

The MI model was generated in male Wistar rats. S-nitrosyl mutant of NEMO (R- NEMO) was selectively delivered to the cardiomyocytes via targeted chitosan nano-vehicle.

RESULTS

Nano-conjugated R- NEMO delivery to diseased cardiomyocytes resulted in downregulation of nitrosative stress and cellular apoptosis leading to regressed infarct area with improved cardiac pathophysiology. Mechanistically, NEMO-p300 binding in R- NEMO expressed cells destabilized p65-p300 complex leading to regressed nitrosative stress and cellular apoptosis. The NEMO mutant inhibits the PGC1α-p65 complex-mediated degradation of PGC1α, leading to upregulation of VEGF. A shift in the binding preference of p65 from PGC1α/p300 to HDAC1 results in the downregulation of the cell-cycle inhibitor and the induction of cell-cycle re-entry markers during MI.

CONCLUSION

Tissue-targeted R- NEMO nanoconjugates show potential to ameliorate MI insult by downregulating apoptosis and promoting the proliferative prowess of the resident cardiomyocytes with potential revascularization at infarct sites; thus, repairing the damaged myocardium.

Partial Cell Fate Transitions to Promote Cardiac Regeneration

Heart disease, including myocardial infarction (MI), remains a leading cause of morbidity and mortality worldwide, necessitating the development of more effective regenerative therapies. Direct reprogramming of cardiomyocyte-like cells from resident fibroblasts offers a promising avenue for myocardial regeneration, but its efficiency and consistency in generating functional cardiomyocytes remain limited. Alternatively, reprogramming induced cardiac progenitor cells (iCPCs) could generate essential cardiac lineages, but existing methods often involve complex procedures. These limitations underscore the need for advanced mechanistic insights and refined reprogramming strategies to improve reparative outcomes in the heart. Partial cellular fate transitions, while still a relatively less well-defined area and primarily explored in longevity and neurobiology, hold remarkable promise for cardiac repair. It enables the reprogramming or rejuvenation of resident cardiac cells into a stem or progenitor-like state with enhanced cardiogenic potential, generating the reparative lineages necessary for comprehensive myocardial recovery while reducing safety risks. As an emerging strategy, partial cellular fate transitions play a pivotal role in reversing myocardial infarction damage and offer substantial potential for therapeutic innovation. This review will summarize current advances in these areas, including recent findings involving two transcription factors that critically regulate stemness and cardiogenesis. It will also explore considerations for further refining these approaches to enhance their therapeutic potential and safety.

Insights into Prime Editing Technology: A Deep Dive into Fundamentals, Potentials, and Challenges

As the most versatile and precise gene editing technology, prime editing (PE) can establish a durable cure for most human genetic disorders. Several generations of PE have been developed based on an editor machine or prime editing guide RNA (pegRNA) to achieve any kind of genetic correction. However, due to the early stage of development, PE complex elements need to be optimized for more efficient editing. Smart optimization of editor proteins as well as pegRNA has been contemplated by many researchers, but the universal PE machine's current shortcomings remain to be solved. The modification of PE elements, fine-tuning of the host genes, manipulation of epigenetics, and blockage of immune responses could be used to reach more efficient PE. Moreover, the host factors involved in the PE process, such as repair and innate immune system genes, have not been determined, and PE cell context dependency is still poorly understood. Regarding the large size of the PE elements, delivery is a significant challenge and the development of a universal viral or nonviral platform is still far from complete. PE versions with shortened variants of reverse transcriptase are still too large to fit in common viral vectors. Overall, PE faces challenges in optimization for efficiency, high context dependency during the cell cycling, and delivery due to the large size of elements. In addition, immune responses, unpredictability of outcomes, and off-target effects further limit its application, making it essential to address these issues for broader use in nonpersonalized gene editing. Besides, due to the limited number of suitable animal models and computational modeling, the prediction of the PE process remains challenging. In this review, the fundamentals of PE, including generations, potential, optimization, delivery, in vivo barriers, and the future landscape of the technology are discussed.

Navigating the prime editing strategy to treat cardiovascular genetic disorders in transforming heart health

INTRODUCTION

After understanding the genetic basis of cardiovascular disorders, the discovery of prime editing (PE), has opened new horizons for finding their cures. PE strategy is the most versatile editing tool to change cardiac genetic background for therapeutic interventions. The optimization of elements, prediction of efficiency, and discovery of the involved genes regulating the process have not been completed. The large size of the cargo and multi-elementary structure makes the in vivo heart delivery challenging.

AREAS COVERED

Updated from recent published studies, the fundamentals of the PEs, their application in cardiology, potentials, shortcomings, and the future perspectives for the treatment of cardiac-related genetic disorders will be discussed.

EXPERT OPINION

The ideal PE for the heart should be tissue-specific, regulatable, less immunogenic, high transducing, and safe. However, low efficiency, sup-optimal PE architecture, the large size of required elements, the unclear role of transcriptomics on the process, unpredictable off-target effects, and its context-dependency are subjects that need to be considered. It is also of great importance to see how beneficial or detrimental cell cycle or epigenomic modifier is to bring changes into cardiac cells. The PE delivery is challenging due to the size, multi-component properties of the editors and liver sink.

Integrative Genetic Approach Facilitates Precision Strategies for Acute Myocardial Infarction

Acute myocardial infarction remains a significant cause of mortality worldwide and its burden continues to grow. Its pathophysiology is known to be complex and multifactorial, with several acquired and inherited risk factors. As advances in technology and medical therapy continue, there is now increasing recognition of the role that genetics play in the development and management of myocardial infarction. The genetic determinants of acute coronary syndrome are still vastly understudied, but the advent of whole-genome scanning and genome-wide association studies has significantly expanded the current understanding of genetics and simultaneously fostered hope that genetic profiling and gene-guided treatments could substantially impact clinical outcomes. The identification of genes associated with acute myocardial infarction can help in the development of personalized medicine, risk stratification, and improved therapeutic strategies. In this context, several genes have been studied, and their potential involvement in increasing the risk for acute myocardial infarction is being investigated. As such, this article provides a review of some of the genes potentially related to an increased risk for acute myocardial infarction as well as the latest updates in gene-guided risk stratification and treatment strategies.

Treating Pulmonary Fibrosis with Non-Viral Gene Therapy: From Bench to Bedside

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by irreversible lung scarring, which achieves almost 80% five-year mortality rate. Undeniably, commercially available pharmaceuticals, such as pirfenidone and nintedanib, exhibit certain effects on improving the well-being of IPF patients, but the stubbornly high mortality still indicates a great urgency of developing superior therapeutics against this devastating disease. As an emerging strategy, gene therapy brings hope for the treatment of IPF by precisely regulating the expression of specific genes. However, traditional administration approaches based on viruses severely restrict the clinical application of gene therapy. Nowadays, non-viral vectors are raised as potential strategies for in vivo gene delivery, attributed to their low immunogenicity and excellent biocompatibility. Herein, we highlight a variety of non-viral vectors, such as liposomes, polymers, and proteins/peptides, which are employed in the treatment of IPF. By respectively clarifying the strengths and weaknesses of the above candidates, we would like to summarize the requisite features of vectors for PF gene therapy and provide novel perspectives on design-decisions of the subsequent vectors, hoping to accelerate the bench-to-bedside pace of non-viral gene therapy for IPF in clinical setting.