CircRNAs: Novel biomarkers and therapeutic targets for diseases of the central nervous system

Circular RNAs (circRNAs) are a class of covalently closed, non-coding RNA molecules characterized by their exceptional stability and tissue-specific expression. Once considered splicing artifacts, they have emerged as pivotal regulators in cellular pathophysiology, particularly within the central nervous system (CNS), where they are highly abundant. This review synthesizes the current understanding of the biogenesis, molecular functions, and regulatory roles of circRNAs in major CNS disorders, underscores their significant potential as next-generation diagnostic and prognostic biomarkers, as well as promising therapeutic targets. Moving from bench to bedside, the review critically examines the burgeoning landscape of circRNA-based therapeutics. We assess the promise and limitations of current delivery platforms, including exosomes and lipid nanoparticles (LNPs), with special attention to the formidable challenge of traversing the blood-brain barrier (BBB). To conclude, we outline the prevailing challenges and future perspectives, emphasizing that the development of more sensitive detection methods and optimized delivery systems is paramount to translating the immense potential of circRNAs into tangible clinical solutions for CNS diseases.