RNA Editing Therapies for Selective Correction of Pathological Cardiac Protein Expression

Abstract

Recent advances in RNA editing have introduced groundbreaking therapeutic opportunities for correcting pathological cardiac protein expression, a key driver of various cardiovascular diseases. This review provides a comprehensive analysis of RNA editing therapies, their underlying mechanisms, clinical applications, and emerging evidence in the context of cardiac proteinopathies. We examine current epidemiological data, disease burden, mechanistic pathways, risk stratification, diagnostic approaches, and the latest clinical guidelines, emphasizing the translational potential and future directions of these precision medicine strategies in cardiology.

Introduction

Cardiovascular diseases (CVDs) remain the leading cause of morbidity and mortality globally, often rooted in aberrant cardiac protein expression due to genetic mutations or acquired molecular dysregulation. Conventional therapeutic approaches, while beneficial, frequently target downstream effects rather than the primary molecular defects. RNA editing—particularly adenosine-to-inosine (A-to-I) and cytosine-to-uracil (C-to-U) editing—has emerged as a precise and potentially transformative modality, enabling the correction of pathogenic RNA transcripts and restoration of normal protein function. This article reviews the rationale, current evidence, and clinical implications of RNA editing therapies for selective correction of pathological cardiac protein expression.

Epidemiology / Disease Burden

The global burden of CVDs is staggering, with the World Health Organization estimating over 17 million deaths annually. Genetic cardiomyopathies, arrhythmias, and heart failure syndromes account for a significant proportion, often linked to mutations in sarcomeric, ion channel, or cytoskeletal proteins. Inherited disorders such as hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC) exemplify conditions where pathogenic protein expression leads to progressive cardiac dysfunction. Despite advances in medical and interventional therapies, disease-modifying options for the root molecular causes remain limited, highlighting the urgent need for innovative solutions like RNA editing.

Pathophysiology

Cardiac proteinopathies arise from single nucleotide variants, splicing defects, or post-transcriptional dysregulation, resulting in either loss-of-function or toxic gain-of-function protein products. For instance, missense mutations in genes encoding cardiac myosin-binding protein C (MYBPC3) or β-myosin heavy chain (MYH7) can disrupt sarcomere architecture, impair contractility, and precipitate heart failure or arrhythmias. RNA editing technologies harness endogenous or engineered enzymes—such as ADAR (adenosine deaminase acting on RNA) or APOBEC (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like)—to selectively modify pre-mRNA transcripts, thereby correcting amino acid sequences at the protein level and restoring physiological function.

Risk Factors

Risk factors for cardiac proteinopathies include family history of inherited cardiomyopathies, presence of pathogenic genetic variants, exposure to environmental toxins, and comorbid conditions such as hypertension or metabolic syndrome that exacerbate underlying molecular defects. The penetrance and expressivity of these disorders can also be modulated by epigenetic factors and modifier genes, further complicating risk stratification and highlighting the necessity for individualized therapeutic strategies based on molecular diagnosis.

Clinical Features

Clinically, patients with pathological cardiac protein expression may present with a spectrum of symptoms ranging from asymptomatic left ventricular hypertrophy or dilation to overt heart failure, syncope, arrhythmias, and sudden cardiac death. Disease onset and severity are highly variable, often correlating with the specific genetic alteration and degree of protein dysfunction. Physical findings may include heart murmurs, signs of heart failure, or arrhythmias detected on electrocardiography and ambulatory monitoring. Early identification of at-risk individuals is critical for timely intervention and prevention of adverse outcomes.

Diagnosis

Diagnosis of proteinopathies typically requires a combination of clinical evaluation, imaging modalities (echocardiography, cardiac MRI), and molecular genetic testing to identify causative variants. Advanced sequencing techniques, including next-generation sequencing (NGS) panels or whole-exome sequencing (WES), facilitate comprehensive assessment of candidate genes. Recent developments in transcriptomics and proteomics provide additional layers of diagnostic insight, allowing for the detection of aberrant RNA or protein species that may be amenable to RNA editing therapies.

Treatment & Management

Conventional management of cardiac proteinopathies focuses on symptomatic control with pharmacological agents (beta-blockers, ACE inhibitors, antiarrhythmics), device therapy (implantable cardioverter-defibrillators), and, in advanced cases, heart transplantation. However, these approaches do not address the underlying molecular pathology. RNA editing therapies, delivered via viral or non-viral vectors, offer the possibility of correcting specific nucleotide changes at the mRNA level, thereby preventing the synthesis of dysfunctional proteins. Preclinical models have demonstrated durable correction of pathogenic transcripts and improvement in cardiac function, with ongoing clinical trials assessing safety, efficacy, and long-term outcomes.

Recent Advances / Emerging Therapies

Recent breakthroughs in programmable RNA editing have expanded the therapeutic landscape for cardiac proteinopathies. CRISPR-Cas13-based systems and evolved ADAR variants now enable site-specific editing with high fidelity and minimal off-target effects. For example, in models of MYBPC3-related HCM, targeted A-to-I editing restored normal protein expression and reversed disease phenotypes. Clinical translation is supported by advances in delivery technologies, such as lipid nanoparticles and engineered viral capsids, which enhance tissue-specific targetability and reduce immunogenicity. The integration of artificial intelligence and machine learning in guide RNA design further optimizes editing precision and therapeutic efficacy.

Guideline Recommendations

While official guidelines from major cardiology societies (AHA, ESC) have yet to incorporate RNA editing therapies into standard care, recent consensus statements underscore the importance of molecular-based risk stratification and personalized therapy. Multidisciplinary evaluation—including genetic counseling, molecular diagnostics, and clinical trial enrollment—is recommended for patients with high-risk genetic variants or refractory disease. Ongoing studies will inform future guideline updates as the safety and efficacy data for RNA editing therapies mature.

Conclusion

RNA editing represents a paradigm shift in the management of pathological cardiac protein expression, offering unprecedented potential for precise, durable, and disease-modifying therapy in genetic and acquired heart diseases. While challenges related to delivery, specificity, and long-term safety remain, the rapid pace of technological advancement and accumulating clinical evidence support the integration of RNA editing into the future armamentarium of cardiovascular therapeutics. Continued collaboration between clinicians, researchers, and regulatory bodies will be essential to translate these innovations into routine clinical practice and improve outcomes for patients with cardiac proteinopathies.