Antisense oligonucleotides: the next frontier for treatment of neurological disorders

ADAMTS5-specific gapmer release from an albumin biomolecular assembly and cartilage internalization triggered by ultrasound

OBJECTIVE

Antisense oligonucleotides (ASOs) have reached the clinic; however, they lack tissue specificity. Albumin is a plasma-abundant macromolecule that has been shown to accumulate in inflamed tissues. In this work, we have designed a recombinant human albumin (rHA)-based biomolecular assembly incorporating a DNase-resistant phosphorothioate-based complementary oligonucleotide (cODN) and an anti-ADAMTS5 ASO for potential delivery to inflamed sites. Ultrasound (US) was used to trigger ASO release from the assembly and enhance internalization into articular cartilage.

METHODS

A phosphorothioate cODN was conjugated to rHA through a maleimide cross-linker after which, a therapeutic ADAMTS5-specific gapmer ASO was annealed to the cODN. ASO release was assessed after exposing the biomolecular assembly to different US conditions using an US-actuated medical needle operating at 32.2 kHz. Gene silencing efficiency of US-treated anti-ADAMTS5 ASO was assessed in human primary chondrocytes isolated from osteoarthritic patients. US-mediated ASO penetration into articular cartilage was assessed on ex vivo bovine articular cartilage.

RESULTS

ASO release was observed after exposure to US waves in continuous mode conditions that did not compromise ASO gene silencing efficiency in human chondrocytes. Furthermore, US increased ASO internalization into bovine articular cartilage after 30 min of application without detrimental effects on chondrocyte viability.

CONCLUSION

A medical needle driven by continuous US waves at 32.2 kHz has the capability of disassembling a duplex oligonucleotide and enhancing released ASOs internalization into articular cartilage. This work offers the potential delivery and the local triggered release of ASOs at the surface of articular cartilage providing potential benefits for the treatment of diverse cartilage pathologies.

Lipid nanoparticle (LNP) mediated mRNA delivery in neurodegenerative diseases

Neurodegenerative diseases (NDD) are characterized by the progressive loss of neurons and the impairment of cellular functions. Messenger RNA (mRNA) has emerged as a promising therapy for treating NDD, as it can encode missing or dysfunctional proteins and anti-inflammatory cytokines or neuroprotective proteins to halt the progression of these diseases. However, effective mRNA delivery to the central nervous system (CNS) remains a significant challenge due to the limited penetration of the blood-brain barrier (BBB). Lipid nanoparticles (LNPs) offer an efficient solution by encapsulating and protecting mRNA, facilitating transfection and intracellular delivery. This review discusses the pathophysiological mechanisms of neurological disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), multiple sclerosis (MS), Huntington's disease (HD), ischemic stroke, spinal cord injury, and Friedreich's ataxia. Additionally, it explores the potential of LNP-mediated mRNA delivery as a therapeutic strategy for these diseases. Various approaches to overcoming BBB-related challenges and enhancing the delivery and efficacy of mRNA-LNPs are discussed, including non-invasive methods with strong potential for clinical translation. With advancements in artificial intelligence (AI)-guided mRNA and LNP design, targeted delivery, gene editing, and CAR-T cell therapy, mRNA-LNPs could significantly transform the treatment landscape for NDD, paving the way for future clinical applications.

Unlocking the future: Precision oligonucleotide therapy for targeted treatment of neurodegenerative disorders

Neurodegenerative disorders are complex and devastating conditions of the central nervous system that profoundly impact quality of life. Given the limited treatment options available, there is a pressing need to develop novel therapeutic strategies. Oligonucleotides have emerged as key players in precision medicine for these disorders, but their potential is hindered by poor translocation across the blood-brain barrier. This review focuses on neurodegenerative disorders other than Alzheimer's and Parkinson's, which are widely reported in the literature, and aims to address the significant hurdles in oligonucleotide delivery for neurodegenerative diseases. It highlights recent advancements in CNS-targeting approaches, such as chemical conjugation, antibody-oligonucleotide conjugates, focused ultrasound, and viral and nanocarrier-based delivery systems. Each strategy's strengths and limitations are discussed, with potential solutions proposed for more effective treatments. Additionally, the review offers valuable insights into regulatory requirements and prospects for clinical translation, which are crucial for shaping the future of neurodegenerative therapies. By exploring these innovative approaches, the goal is to surmount challenges posed by the blood-brain barrier and develop more effective treatments, thereby enhancing the quality of life of the patients suffering from these debilitating conditions.

Antisense Oligonucleotides: A Promising Advancement in Neurodegenerative Disease Treatment

Antisense oligonucleotides (ASOs) are a class of therapeutics designed to modulate gene expression and have shown promise in the treatment of various neurodegenerative diseases. As of March 2025, four ASO-based therapies have received approval for the treatment of neurodegenerative diseases, including spinal muscular atrophy (SMA), amyotrophic lateral sclerosis (ALS), and hereditary transthyretin amyloidosis (ATTR). These approvals underscore the therapeutic potential of ASOs as effective treatments for neurodegenerative diseases by addressing specific genetic abnormalities. This is best demonstrated by clinical studies in more than a dozen ASOs, which could pave the way for the development of new therapeutics soon. Moreover, the ongoing extended clinical studies, which target presymptomatic carriers, have significant potential to cure familial ALS based on the SOD1 gene mutation. This review provides an update on clinical trials, highlighting promising results and the challenges encountered.

Conjugation to a transferrin receptor 1-binding Bicycle peptide enhances ASO and siRNA potency in skeletal and cardiac muscles

Improving the delivery of antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs) to skeletal and cardiac muscles remains a pivotal task toward the broader application of oligonucleotide therapeutics. The targeting of myofibers and cardiomyocytes via conjugation of ASOs and siRNAs to ligands that bind the human transferrin receptor 1 (TfR1) has gathered significant interest in recent years. However, the selection of ligands with low molecular weight and optimal biophysical and binding properties is crucial to maximize the potential of the TfR1 ligand-conjugated antisense (LICA) technology. Here, through effective combination of phage display and peptide medicinal chemistry, we identified and characterized a bicyclic peptide (Bicycle® molecule BCY17901), with a molecular weight of ∼2 kDa, that binds human TfR1 with high affinity and specificity. Conjugation to BCY17901 improved ASO and siRNA potency in skeletal and cardiac muscles of human TfR1 knock-in mice, after either intravenous or subcutaneous administration. Furthermore, single-nucleus RNA sequencing showed that conjugation to BCY17901 enhanced ASO activity in myonuclei of different muscle fiber types. Importantly, we demonstrated good translatability of our TfR1-targeting platform in skeletal and cardiac muscles of nonhuman primates. Our results offer great promise toward potential future applications of low-molecular-weight Bicycle LICA therapeutics for the treatment of diseases affecting skeletal muscle and heart.

Photoelectrocatalyzed Alkylation of Phosphonites by Direct Decarboxylative C(sp3)-P Coupling

A photoelectrocatalytic method is presented that achieves direct decarboxylative C(sp3)-P coupling, providing a modular route to alkylphosphinates and alkylphosphonates from readily available carboxylic acids. The success of this reaction hinges on the synergistic combination of electrochemical anodic oxidation and photocatalytic ligand to metal charge transfer (LMCT) decarboxylation. By employing P(III) reagents as limiting reagents, our approach enables efficient alkyl modification of medicinally important nucleosides and complex molecules derived phosphonites, which were challenging to access by existing methods. Detailed mechanistic studies elucidate the critical roles of Fe catalysts and additives, offering valuable insights into the reaction pathway and laying the foundation for future advancements in photoelectrocatalytic C(sp3)-heteroatom bond-forming reactions.

Myotonic dystrophies: an update on clinical features, molecular mechanisms, management, and gene therapy

Myotonic dystrophies (DM) encompass a group of complex genetic disorders characterized by progressive muscle weakness with myotonia and multisystemic involvement. The aim of our paper is to synthesize key findings and advancements in the understanding of DM, and to underline the multidisciplinary approach to DM, emphasizing the importance of genetic counseling, comprehensive clinical care, and symptom management. We discuss the genetic basis of DM, emphasizing the role of repeat expansions in disease pathogenesis, as well as cellular and animal models utilized for studying DM mechanisms and testing potential therapies. Diagnostic challenges, such as determining the size of disease expansions and assessing mosaicism, are elucidated alongside emerging genetic testing methods. Therapeutic strategies, mainly for DM1, are also explored, encompassing small molecules, nucleic acid-based therapies (NATs), and genome/transcriptome engineering. The challenges of such a therapeutic delivery and immunogenic response and the importance of innovative strategies, including viral vectors and AAV serotypes, are highlighted within the text. While no curative treatments have been approved, supportive and palliative care remains essential, with a focus on addressing multisystemic complications and maintaining functional independence. Continued exploration of these therapeutic advancements offers hope for comprehensive disease management and potentially curative therapies for DM1 and related disorders.

Targeted protein degradation with bifunctional molecules as a novel therapeutic modality for Alzheimer's disease & beyond

Alzheimer's disease (AD) is associated with memory and cognitive impairment caused by progressive degeneration of neurons. The events leading to neuronal death are associated with the accumulation of aggregating proteins in neurons and glia of the affected brain regions, in particular extracellular deposition of amyloid plaques and intracellular formation of tau neurofibrillary tangles. Moreover, the accumulation of pathological tau proteoforms in the brain concurring with disease progression is a key feature of multiple neurodegenerative diseases, called tauopathies, like frontotemporal dementia (FTD) where autosomal dominant mutations in the tau encoding MAPT gene provide clear evidence of a causal role for tau dysfunction. Observations from disease models, post-mortem histology, and clinical evidence have demonstrated that pathological tau undergoes abnormal post-translational modifications, misfolding, oligomerization, changes in solubility, mislocalization, and intercellular spreading. Despite extensive research, there are few disease-modifying or preventative therapeutics for AD and none for other tauopathies. Challenges faced in tauopathy drug development include an insufficient understanding of pathogenic mechanisms of tau proteoforms, limited specificity of agents tested, and inadequate levels of brain exposure, altogether underscoring the need for innovative therapeutic modalities. In recent years, the development of experimental therapeutic modalities, such as targeted protein degradation (TPD) strategies, has shown significant and promising potential to promote the degradation of disease-causing proteins, thereby reducing accumulation and aggregation. Here, we review all modalities of TPD that have been developed to target tau in the context of AD and FTD, as well as other approaches that with innovation could be adapted for tau-specific TPD.

Long Non-coding RNA Involved in the Pathophysiology of Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is a prevalent and chronic cardiovascular disorder associated with various pathophysiological alterations, including atrial electrical and structural remodeling, disrupted calcium handling, autonomic nervous system dysfunction, aberrant energy metabolism, and immune dysregulation. Emerging evidence suggests that long non-coding RNAs (lncRNAs) play a significant role in the pathogenesis of AF.

OBJECTIVE

This discussion aims to elucidate the involvement of AF-related lncRNAs, with a specific focus on their role as miRNA sponges that modulate crucial signaling pathways, contributing to the progression of AF. We also address current limitations in AF-related lncRNA research and explore potential future directions in this field. Additionally, we summarize feasible strategies and promising delivery systems for targeting lncRNAs in AF therapy.

CONCLUSION

In conclusion, targeting AF-related lncRNAs holds substantial promise for future investigations and represents a potential therapeutic avenue for managing AF.

Synthetic-polymer-assisted antisense oligonucleotide delivery: targeted approaches for precision disease treatment

This review explores the recent advancements in polymer-assisted delivery systems for antisense oligonucleotides (ASOs) and their potential in precision disease treatment. Synthetic polymers have shown significant promise in enhancing the delivery, stability, and therapeutic efficacy of ASOs by addressing key challenges such as cellular uptake, endosomal escape, and reducing cytotoxicity. The review highlights key studies from the past decade demonstrating how these polymers improve gene silencing efficiencies, particularly in cancer and neurodegenerative disease models. Despite the progress achieved, barriers such as immunogenicity, delivery limitations, and scalability still need to be overcome for broader clinical application. Emerging strategies, including stimuli-responsive polymers and advanced nanoparticle systems, offer potential solutions to these challenges. The review underscores the transformative potential of polymer-enhanced ASO delivery in personalised medicine, emphasising the importance of continued innovation to optimise ASO-based therapeutics for more precise and effective disease treatments.

Recent advances in RNA-based therapeutics for neurodevelopmental disorders

A significant proportion of neurodevelopmental disorders (NDDs) are caused by gain-of-function (GOF) or loss-of-function (LOF) of specific genes. Strategies to normalize disease gene expression offer therapeutic potential for these disorders. The success and approval of RNA-based therapeutics for various disorders have led to a surge in RNA-based therapeutic research for NDDs with antisense oligonucleotides leading the field. This review discusses recent advances in therapeutic strategies that target pre-mRNA or mRNA for GOF and LOF NDDs that have promising preclinical evidence. These developments highlight important considerations and exciting future avenues for the development of therapies for NDDs.

Immunotherapy and vaccine-based approaches for atherosclerosis prevention: a systematic review study

INTRODUCTION

Cardiovascular disease is a major global health issue, and atherosclerosis is a leading cause of cardiovascular conditions. Traditional approaches for managing atherosclerosis have limitations, creating a need for alternative preventive strategies such as vaccines.

METHODS

The authors conducted a systematic review following Cochrane Handbook and PRISMA guidelines. They searched multiple databases for studies on preventive vaccines against atherosclerosis, including clinical trials and experimental models. The search period was from 1950 to August 2024.

RESULTS

After screening and evaluation, 47 studies were included in the systematic review. The studies investigated various vaccine candidates and immunization strategies. Vaccination goals involve targeting proteins that are found in higher quantities in individuals with atherosclerosis, such as oxidized low-density lipoprotein (LDL), apolipoprotein B-100, proprotein convertase subtilisin/kexin type-9 serine protease (PCSK9), cholesteryl ester transfer protein (CETP), and heat shock proteins HSP60 and HSP65. The review highlights the potential of vaccines in preventing atherosclerosis by targeting specific antigens, modulating lipoprotein metabolism, and enhancing immune responses. Promising approaches included PCSK9 inhibitors, virus-like particle (VLP)-based vaccines, and gene-editing techniques. Monoclonal antibodies like alirocumab, designed to inhibit PCSK9, were also effective in reducing LDL cholesterol levels.

CONCLUSION

This systematic review provides insights into the progress, challenges, and future directions of preventive vaccine research against atherosclerosis. The findings support the development of effective vaccines to complement existing preventive strategies and reduce the global burden of cardiovascular diseases.

CLINICAL TRIAL NUMBER

It is not applicable.

Alternative splicing in addiction

Addiction is a chronic and relapsing medical condition characterized by the compulsive use of drugs or alcohol despite harmful consequences. While transcriptional regulation has long been recognized for its role in addiction, recent genome-wide analyses have uncovered widespread alternative splicing changes that shift protein isoform diversity in multiple brain reward regions central to addiction. In this review, we discuss emerging research and evidence that alternative splicing is dysregulated in cocaine, alcohol, and opioid use disorders.

In vivo efficacy and safety of systemically administered serinol nucleic acid-modified antisense oligonucleotides in mouse kidney

Nucleic acid medicine encompassing antisense oligonucleotides (ASOs) has garnered interest as a potential avenue for next-generation therapeutics. However, their therapeutic application has been constrained by challenges such as instability, off-target effects, delivery issues, and immunogenic responses. Furthermore, their practical utility in treating kidney diseases remains unrealized. Recently, we developed a serinol nucleic acid-modified ASO (SNA-ASO) that exhibits significant nuclease resistance. In this study, we evaluated the in vivo efficacy of SNA-ASOs in mouse kidney. We subcutaneously administered various types of phosphorothioate-modified gapmer ASOs with SNA or 2'-O-methoxyethyl (2'-MOE) modifications (MOE-ASO) targeting sodium glucose cotransporter 2 (SGLT2) in mice. The subcutaneous administration of SGLT2-SNA-ASO led to a dose-dependent reduction in renal SGLT2 expression and subsequent glucosuria. The inhibitory effects of SGLT2-SNA-ASO were more potent and prolonged than those of ASOs without SNA. Moreover, SGLT2-SNA-ASO did not cause severe liver damage, unlike SGLT2-MOE-ASO. The administration of Cy5-labeled-ASOs demonstrated an early increase in renal uptake, particularly in the renal proximal tubules, when modified with SNA. In conclusion, systemic administration of SGLT2-ASO modified with the artificial nucleic acid SNA effectively suppressed renal SGLT2 expression and induced urinary glucose excretion. These results suggest that SNA-modified ASOs show potential for application in developing nucleic acid therapeutics.

Nucleic acid therapeutics: Past, present, and future

Nucleic acid therapeutics have become increasingly recognized in recent years for their capability to target both coding and non-coding sequences. Several types of nucleic acid modalities, including siRNA, mRNA, aptamer, along with antisense oligo, have been approved by regulatory bodies for therapeutic use. The field of nucleic acid therapeutics has been brought to the forefront by the rapid development of vaccines against COVID-19, followed by a number of approvals for clinical use including much anticipated CRISPR-Cas9. However, obstacles such as the difficulty of achieving efficient and targeted delivery to diseased sites remain. This review provides an overview of nucleic acid therapeutics and highlights substantial advancements, including critical engineering, conjugation, and delivery strategies, that are paving the way for their growing role in modern medicine.

Landscape of small nucleic acid therapeutics: moving from the bench to the clinic as next-generation medicines

The ability of small nucleic acids to modulate gene expression via a range of processes has been widely explored. Compared with conventional treatments, small nucleic acid therapeutics have the potential to achieve long-lasting or even curative effects via gene editing. As a result of recent technological advances, efficient small nucleic acid delivery for therapeutic and biomedical applications has been achieved, accelerating their clinical translation. Here, we review the increasing number of small nucleic acid therapeutic classes and the most common chemical modifications and delivery platforms. We also discuss the key advances in the design, development and therapeutic application of each delivery platform. Furthermore, this review presents comprehensive profiles of currently approved small nucleic acid drugs, including 11 antisense oligonucleotides (ASOs), 2 aptamers and 6 siRNA drugs, summarizing their modifications, disease-specific mechanisms of action and delivery strategies. Other candidates whose clinical trial status has been recorded and updated are also discussed. We also consider strategic issues such as important safety considerations, novel vectors and hurdles for translating academic breakthroughs to the clinic. Small nucleic acid therapeutics have produced favorable results in clinical trials and have the potential to address previously "undruggable" targets, suggesting that they could be useful for guiding the development of additional clinical candidates.

DNA nanotechnology-based strategies for minimising hybridisation-dependent off-target effects in oligonucleotide therapies

Targeted therapy has emerged as a transformative breakthrough in modern medicine. Oligonucleotide drugs, such as antisense oligonucleotides (ASOs) and small interfering RNAs (siRNAs), have made significant advancements in targeted therapy. Other oligonucleotide-based therapeutics like clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) systems are also leading a revolution in targeted gene therapy. However, hybridisation-dependent off-target effects, arising from imperfect base pairing, remain a significant and growing concern for the clinical translation of oligonucleotide-based therapeutics. These mismatches in base pairing can lead to unintended steric blocking or cleavage events in non-pathological genes, affecting the efficacy and safety of the oligonucleotide drugs. In this review, we examine recent developments in oligonucleotide-based targeted therapeutics, explore the factors influencing sequence-dependent targeting specificity, and discuss the current approaches employed to reduce the off-target side effects. The existing strategies, such as chemical modifications and oligonucleotide length optimisation, often require a trade-off between specificity and binding affinity. To further address the challenge of hybridisation-dependent off-target effects, we discuss DNA nanotechnology-based strategies that leverage the collaborative effects of nucleic acid assembly in the design of oligonucleotide-based therapies. In DNA nanotechnology, collaborative effects refer to the cooperative interactions between individual strands or nanostructures, where multiple bindings result in more stable and specific hybridisation behaviour. By requiring multiple complementary interactions to occur simultaneously, the likelihood of unintended partially complementary binding events in nucleic acid hybridisation should be reduced. And thus, with the aid of collaborative effects, DNA nanotechnology has great promise in achieving both high binding affinity and high specificity to minimise the hybridisation-dependent off-target effects of oligonucleotide-based therapeutics.

A novel lncRNA FLJ promotes castration resistance in prostate cancer through AR mediated autophagy

BACKGROUND

Progression to castration resistance is the leading cause of death in prostate cancer patients. Long non-coding RNAs (lncRNAs) have recently become a focal point in the regulation of cancer development. However, few lncRNAs associated with castration-resistant prostate cancer (CRPC) have been reported.

METHODS

Firstly, we explore the CRPC associated lncRNAs by RNA sequencing and validated using quantitative polymerase chain reaction (qRT-PCR) and RNA fluorescence in situ hybridization (RNA-FISH). The clinical significance of FLJ was evaluated in a collected cancer cohort. Functional loss assays were performed to assess the effects of FLJ on CRPC cells both in vitro and in vivo. The regulatory mechanism of FLJ was investigated using immunohistochemistry (IHC), qRT-PCR, dual-luciferase reporter assays, and chromatin immunoprecipitation (ChIP) assays.

RESULTS

FLJ is highly expressed in CRPC and is associated with higher stages and Gleason scores in prostate cancer. FLJ is strongly positively correlated with androgen receptor (AR), which acts as a transcription factor and directly binds to the FLJ promoter region to enhance its transcription. Knockdown of FLJ inhibits CRPC cell proliferation and increases sensitivity to castration and enzalutamide (ENZA) in vitro. Mechanistically, FLJ promotes castration resistance in prostate cancer cells by inhibiting AR nuclear import and cytoplasmic protein degradation, thereby activating the androgen-independent AR signaling pathway. Importantly, in vivo experiments showed that FLJ knockdown inhibited tumor growth and enhanced the therapeutic effect of ENZA.

CONCLUSIONS

This study identifies a novel regulatory mechanism by which lncRNA FLJ promotes CRPC progression. Sustained AR activation in CRPC acts as a transcription factor to upregulate FLJ expression. FLJ circumvents the traditional androgen-dependent survival mechanism by inhibiting AR nuclear entry and cytoplasmic protein degradation, thereby activating the AR signaling pathway. Targeting the FLJ-AR signaling axis may represent a novel therapeutic strategy for patients with castration-resistant prostate cancer.

CASCADES, a novel SOX2 super-enhancer-associated long noncoding RNA, regulates cancer stem cell specification and differentiation in glioblastoma

Glioblastoma is the most common primary malignant brain tumor in adults, with a median survival of just over 1 year. The failure of available treatments to achieve remission in patients with glioblastoma (GBM) has been attributed to the presence of cancer stem cells (CSCs), which are thought to play a central role in tumor development and progression and serve as a treatment-resistant cell repository capable of driving tumor recurrence. In fact, the property of "stemness" itself may be responsible for treatment resistance. In this study, we identify a novel long noncoding RNA (lncRNA), cancer stem cell-associated distal enhancer of SOX2 (CASCADES), that functions as an epigenetic regulator in glioma CSCs (GSCs). CASCADES is expressed in isocitrate dehydrogenase (IDH)-wild-type GBM and is significantly enriched in GSCs. Knockdown of CASCADES in GSCs results in differentiation towards a neuronal lineage in a cell- and cancer-specific manner. Bioinformatics analysis reveals that CASCADES functions as a super-enhancer-associated lncRNA epigenetic regulator of SOX2. Our findings identify CASCADES as a critical regulator of stemness in GSCs that represents a novel epigenetic and therapeutic target for disrupting the CSC compartment in glioblastoma.

Nonlocal models in biology and life sciences: Sources, developments, and applications

Mathematical modeling is one of the fundamental techniques for understanding biophysical mechanisms in developmental biology. It helps researchers to analyze complex physiological processes and connect like a bridge between theoretical and experimental observations. Various groups of mathematical models have been studied to analyze these processes, and the nonlocal models are one of them. Nonlocality is important in realistic mathematical models of physical and biological systems when local models fail to capture the essential dynamics and interactions that occur over a range of distances (e.g., cell-cell, cell-tissue adhesions, neural networks, the spread of diseases, intra-specific competition, nanobeams, etc.). This review illustrates different nonlocal mathematical models applied to biology and life sciences. The major focus has been given to sources, developments, and applications of such models. Among other things, a systematic discussion has been provided for the conditions of pattern formations in biological systems of population dynamics. Special attention has also been given to nonlocal interactions on networks, network coupling and integration, including brain dynamics models that provide an important tool to understand neurodegenerative diseases better. In addition, we have discussed nonlocal modeling approaches for cancer stem cells and tumor cells that are widely applied in the cell migration processes, growth, and avascular tumors in any organ. Furthermore, the discussed nonlocal continuum models can go sufficiently smaller scales, including nanotechnology, where classical local models often fail to capture the complexities of nanoscale interactions, applied to build biosensors to sense biomaterial and its concentration. Piezoelectric and other smart materials are among them, and these devices are becoming increasingly important in the digital and physical world that is intrinsically interconnected with biological systems. Additionally, we have reviewed a nonlocal theory of peridynamics, which deals with continuous and discrete media and applies to model the relationship between fracture and healing in cortical bone, tissue growth and shrinkage, and other areas increasingly important in biomedical and bioengineering applications. Finally, we provided a comprehensive summary of emerging trends and highlighted future directions in this rapidly expanding field.

Chemical evolution of ASO-like DNAzymes for effective and extended gene silencing in cells

Antisense oligonucleotides (ASOs) and small interfering RNA (siRNA) therapeutics highlight the power of oligonucleotides in silencing disease-causing messenger RNAs (mRNAs). Another promising class of gene-silencing oligonucleotides is RNA-cleaving nucleic acid enzymes, which offer the potential for allele-specific RNA inhibition with greater precision than ASOs and siRNAs. Herein, we chemically evolved the nucleolytic DNA enzyme (DNAzyme) 10-23, by incorporating the modifications that are essential to the success of ASO drugs, including 2'-fluoro, 2'-O-methyl, and 2'-O-methoxyethyl RNA analogues, and backbone phosphorothioate, to enhance catalytic efficiency by promoting RNA substrate binding and preventing dimerization of 10-23. These ASO-like DNAzymes cleaved structured RNA targets in long transcripts, showed prolonged intracellular stability, and downregulated mRNA and protein levels of both exogenously transfected eGFP and endogenously elevated oncogenic c-MYC. In colon cancer HCT116 cells, the downregulation of oncogenic c-MYC RNA resulted in cell cycle arrest, reduced proliferation, and increased apoptosis. RACE (rapid amplification of cDNA ends) polymerase chain reaction and Sanger sequencing confirmed precise, site-specific mRNA transcript cleavage with minimal RNase H activation in cells. By merging ASO structural and pharmacokinetic advantages with DNAzyme catalytic versatility, these ASO-like 10-23 variants offer a promising new class of potent gene-silencing agents, representing a significant step toward therapeutic DNAzyme development.

Lipid Nanovesicles in Cancer Treatment: Improving Targeting and Stability of Antisense Oligonucleotides

Cancer remains a leading cause of mortality worldwide, accounting for approximately 10 million deaths annually. Standard treatments, including surgery, radiotherapy, and chemotherapy, often result in damage to healthy cells and severe toxic side effects. In recent years, antisense technology therapeutics, which interfere with RNA translation through complementary base pairing, have emerged as promising approaches for cancer treatment. Despite the availability of various antisense oligonucleotide (ASO) drugs on the market, challenges such as poor active targeting and susceptibility to clearance by circulating enzymes remain. Compared with other delivery systems, lipid nanovesicle (LNV) delivery systems offer a potential solution that uniquely enhances ASO targeting and stability. Studies have shown that LNVs can increase the accumulation of ASOs in tumor sites several-fold, significantly reducing systemic toxic reactions and demonstrating increased therapeutic efficiency in preclinical models. Additionally, LNVs can protect ASOs from enzymatic degradation within the body, extending their half-life and thus enhancing their therapeutic effects. This paper provides a comprehensive review of recent examples and applications of LNV delivery of ASOs in cancer treatment, highlighting their unique functions and outcomes. Furthermore, this paper discusses the key challenges and potential impacts of this innovative approach to cancer therapy.

MicroRNA-34a-5p regulates agouti-related peptide via krüppel-like factor 4 and is disrupted by bisphenol A in hypothalamic neurons

Obesity is a complex disease marked by increased adiposity and impaired metabolic function. While diet and lifestyle are primary causes, endocrine-disrupting chemicals (EDCs), such as bisphenol A (BPA), significantly contribute to obesity. BPA, found in plastic consumer products, accumulates in the hypothalamus and dysregulates energy homeostasis by disrupting the neuropeptide Y (NPY)/agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC) neurons. However, the precise molecular mechanisms of how BPA disrupts neuropeptide expression remains unclear. We hypothesized that microRNAs (miRNAs), which regulate approximately 60% of the human protein-coding genome and are crucial for hypothalamic energy regulation, may mediate the effects of BPA on Agrp. Using the TargetScanMouse 8.0 and DIANA microT bioinformatics tools, we identified miR-501-5p as a potential miRNA that directly regulates Agrp and the miR-34 family as miRNAs that indirectly regulate Agrp through its transcription factor krüppel-like factor 4 (KLF4). We found that in an immortalized NPY/AgRP-expressing cell line, mHypoE-41, miR-501-5p unexpectedly upregulated Agrp, while miR-34a-5p reduced Klf4 and Agrp mRNA levels. Serum starvation reduced miR-34a-5p levels and elevated Agrp mRNA levels, suggesting a potential role in AgRP regulation. Inhibiting the miR-34a-5p interaction with the Klf4 3'UTR using a specific target site blocker prevented the downregulation of both Klf4 and Agrp, suggesting miR-34a-5p alters Agrp mRNA levels via regulation of KLF4. BPA treatment increased Agrp and Klf4 expression while simultaneously decreasing miR-34a-5p levels, indicating miR-34a-5p may play a role in BPA-mediated dysregulation of Agrp. Overall, this study highlights indirect miRNA-based regulation of Agrp, which can also be dysregulated by obesogens, such as BPA.

Lipid nanoparticles and transcranial focused ultrasound enhance the delivery of SOD1 antisense oligonucleotides to the murine brain for ALS therapy

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease with extremely limited therapeutic options. One key pathological feature of ALS is the abnormal accumulation of misfolded proteins within motor neurons. Hence, reducing the burden of misfolded protein has emerged as a promising therapeutic approach. Antisense oligonucleotides (ASOs) have the potential to effectively silence proteins with gain-of-function mutations, such as superoxide dismutase 1 (SOD1). However, ASO delivery to the central nervous system (CNS) is hindered by poor blood-brain barrier (BBB) penetration and the invasiveness of intrathecal administration. In the current study, we demonstrate effective systemic delivery of a next-generation SOD1 ASO (Tofersen) into the brain of wildtype and G93A-SOD1 transgenic C57BL/6 mice using calcium phosphate lipid nanoparticles (CaP lipid NPs). We show that transcranial focused ultrasound (FUS) with intravenously administered microbubbles can significantly enhance ASO-loaded nanoparticle delivery into the mouse brain. Magnetic resonance imaging (MRI) and immunohistological analysis showed reduced SOD1 expression in the FUS-exposed brain regions and increased motor neuron count in the spinal cord of treated mice suggesting decreased motor neuron degeneration. Importantly, the BBB opening was transient without evidence of structural changes, neuroinflammation or damage to the brain tissue, indicating that the treatment is well tolerated. Overall, our results highlight FUS-assisted nanoparticle delivery of ASOs as a promising non-invasive therapeutic strategy for the treatment of ALS and CNS diseases more broadly.

Targeting Drug Delivery System to Skeletal Muscles: A Comprehensive Review of Different Approaches

The skeletal muscle is one of the largest organs in the body and is responsible for the mechanical activity required for posture, movement and breathing. The effects of current pharmaceutical therapies for skeletal muscle diseases are far from satisfactory; approximately 24% of Duchenne muscular dystrophy (DMD) trials have been terminated because of unsatisfactory outcomes. The lack of a skeletal muscle-targeting strategy is a major reason for these unsuccessful trials, contributing to low efficiency and severe side effects. The development of targeting strategies for skeletal muscle-specific drug delivery has shown the potential for increasing drug concentrations in the skeletal muscle, minimising off-target effects, and thereby improving the therapeutic effects of drugs. Over the past few decades, novel methods for specifically delivering cargo to skeletal muscles have been developed. In this review, we categorise targeting methods into four types: peptides, antibodies, small molecules and aptamers. Most research has focused on peptide and antibody ligands, and there are several well-established drugs in this category; however, drawbacks such as protease degradation and immunogenicity limit their use. Aptamers and small molecules have low immunogenicity and are simple to chemically produce. However, small molecule ligands generally exhibit lower affinity because of their small size and high mobility. Aptamers are promising ligands for skeletal muscle-targeting delivery systems. Additionally, if the active site of the cargo is located inside the cell, an internalisation pathway becomes necessary. The order of internalisation ligands and targeting ligands in the complex is a crucial factor, because an inappropriate order could lead to much lower targeting and internalisation efficiencies. Moreover, ligand density also merits consideration, as increasing the density of the targeting ligands may result in steric hindrance, which could impact the accessibility of the receptor and cause enlargement of the targeted ligands. More efforts are required to optimise drug delivery systems that specifically recognise skeletal muscle, with the aim of enhancing quality of life and promoting patient well-being.

Epigenetic regulation in coronary artery disease: from mechanisms to emerging therapies

Atherosclerosis, the primary cause of coronary artery disease (CAD), remains a leading global cause of mortality. It is characterized by the accumulation of cholesterol-rich plaques and inflammation, which narrow the coronary arteries and increase the risk of rupture. To elucidate this complex biological process and improve therapeutic strategies, CAD has been extensively explored from an epigenetic perspective over the past two decades. Epigenetics is a field investigating heritable alterations in gene expression without DNA sequence changes, such as DNA methylation, histone modifications, and non-coding RNAs. Increasing evidence has indicated that the development of CAD is significantly influenced by epigenetic changes. Meanwhile, the impact of epigenetics in CAD is now transitioning from pathophysiology to therapeutics. Focusing on the key epigenetic enzymes and their target genes will help to facilitate the diagnosis and treatment of CAD. This review synthesizes novel epigenetic insights into CAD, addressing the pathological processes, key molecular mechanisms, and potential biomarkers. Furthermore, we discuss emerging therapeutic strategies targeting epigenetic pathways. By focusing on pivotal enzymes and their associated genes, this work aims to advance CAD diagnostics and interventions.

Molecular and cellular characteristics of cerebrovascular cell types and their contribution to neurodegenerative diseases

Many diseases and disorders of the nervous system suffer from a lack of adequate therapeutics to halt or slow disease progression, and to this day, no cure exists for any of the fatal neurodegenerative diseases. In part this is due to the incredible diversity of cell types that comprise the brain, knowledge gaps in understanding basic mechanisms of disease, as well as a lack of reliable strategies for delivering new therapeutic modalities to affected areas. With the advent of single cell genomics, it is now possible to interrogate the molecular characteristics of diverse cell populations and their alterations in diseased states. More recently, much attention has been devoted to cell populations that have historically been difficult to profile with bulk single cell technologies. In particular, cell types that comprise the cerebrovasculature have become increasingly better characterized in normal and neurodegenerative disease contexts. In this review, we describe the current understanding of cerebrovasculature structure, function, and cell type diversity and its role in the mechanisms underlying various neurodegenerative diseases. We focus on human and mouse cerebrovasculature studies and discuss both origins and consequences of cerebrovascular dysfunction, emphasizing known cell type-specific vulnerabilities in neuronal and cerebrovascular cell populations. Lastly, we highlight how novel insights into cerebrovascular biology have impacted the development of modern therapeutic approaches and discuss outstanding questions in the field.

Analysis of Exon Skipping Applicability for Dysferlinopathies

Exon skipping, mediated through antisense oligonucleotides (ASOs), is a promising approach to exclude pathogenic variants from the DYSF gene and treat dysferlinopathies. Understanding the applicability of various exon skipping strategies in the total patient population, an analysis not previously performed, can help guide researchers in prioritizing therapies with the broadest potential impact. Using data from the UMD-DYSF database, we evaluated all reported pathogenic variants in dysferlinopathy patients for the applicability of single- or double-exon skipping approaches to exclude the pathogenic variants while maintaining the open reading frame. A total of 61 theoretically applicable exon skipping strategies were identified, with the potential to address 90.0% of the pathogenic variants reported-44.6% through single-exon skipping and 45.3% through double-exon skipping. The most broadly applicable targets include exons 28 and 29 (9.0%), exons 27 and 28 (6.7%), and exons 50 and 51 (5.4%). While numerous theoretically applicable strategies were identified, it remains unclear if the truncated proteins produced through each exon skipping strategy will have improved functionality to alleviate patient symptoms. Further preclinical studies and clinical trials will be essential to determine the effectiveness of these therapies, potentially expanding access to disease-modifying treatments for dysferlinopathy patients.

Click Chemistry Methodology: The Novel Paintbrush of Drug Design

Click chemistry is an immensely powerful technique for the synthesis of reliable and efficient covalent linkages. When undertaken in living cells, the concept is thereby coined bioorthogonal chemistry. Used in conjunction with the photo-cross-linking methodology, it serves as a sound strategy in the exploration of biological processes and beyond. Its broad scope has led to widespread use in many disciplines; however, this Review focuses on the use of click and bioorthogonal chemistry within medicinal chemistry, specifically with regards to drug development applications, namely, the use of DNA-encoded libraries as a novel technique for lead compound discovery, as well as the synthesis of antisense oligonucleotides and protein-drug conjugates. This Review aims to provide a critical perspective and a future outlook of this methodology, such as potential widespread use in cancer therapy and personalized medicine.

Self-Assembled Antibody-Oligonucleotide Conjugates for Targeted Delivery of Complementary Antisense Oligonucleotides

Antibody-oligonucleotide conjugate (AOC) affords preferential cell targeting and enhanced cellular uptake of antisense oligonucleotide (ASO). Here, we have developed a modular AOC (MAOC) approach based on accurate self-assembly of separately prepared antibody and ASO modules. Homogeneous multimeric AOC with defined ASO-to-antibody ratio were generated by L-DNA scaffold mediated precise self-assembly of antibodies and ASOs. The MAOC approach has been implemented to deliver exon skipping ASOs via transferrin receptor (TfR1) mediated internalization. We discovered an anti-TfR1 sdAb that can greatly enhance nuclear delivery of ASOs. Cryo-EM structure of the sdAb-TfR1 complex showed a new epitope that does not overlap with the binding sites of endogenous TfR1 ligands. In vivo functional analyses of MAOCs with one ASO for single exon skipping and two ASOs for double exon skipping showed that both ASO concentration and exon skipping efficacy of MAOC in cardiac and skeletal muscles are dramatically higher than conventional ASOs in the transgenic human TfR1 mouse model. MAOC treatment was well tolerated in vivo and not associated with any toxicity-related morbidity or mortality. Collectively, our data suggest that the self-assembled MAOC is a viable option for broadening the therapeutic application of ASO via multi-specific targeting and delivery.

OligoDistiller: A Platform Agnostic Software Tool for MS and MS2 Data Analysis of Complex Oligonucleotides and Their Impurities

Oligonucleotides are currently one of the most rapidly advancing classes of therapeutic modalities. Understanding critical quality attributes, such as the impurity profile, stability, potential metabolites, and sequence conformity, is the key to their ultimate success. To obtain the information presented above, liquid chromatography-mass spectrometry (LC-MS) is often employed. However, data interpretation can be challenging due to multiple charge states, unknown species, chemical noises, and overlapping isotope envelopes (OIEs) of distinct but unresolved species. To address these challenges, we have developed an MS-platform agnostic, multifunctional R package and a web-tool for automated and interactive MS and MS2 data analysis, OligoDistiller. From the MS spectrum of a complex mixture of two synthetic strands, our tool OligoDistiller annotated and quantified 45 oligonucleotide-related features including 13 unknown impurities and 6 OIEs, which all together explained 90.8% of the detected peaks. Also, major product ions were assigned from the MS2 spectrum of a 47-mer DNA strand, covering 80.3% of the oligonucleotide sequence. We provide not only diverse isotope quality metrics for each annotated feature but also an interactive data review module allowing for direct inspection of the part of raw spectrum linked to a selected feature. This tool OligoDistiller is freely available at https://github.com/daniellyz/OligoDistiller.

Translational Approach using Advanced Therapy Medicinal Products for Huntington's Disease

Current therapeutic approaches for Huntington's disease (HD) focus on symptomatic treatment. Therefore, the unavailability of efficient disease-modifying medicines is a significant challenge. Regarding the molecular etiology, targeting the mutant gene or advanced translational steps could be considered promising strategies. The evidence in gene therapy suggests various molecular techniques, including knocking down mHTT expression using antisense oligonucleotides and small interfering RNAs and gene editing with zinc finger proteins and CRISPR-Cas9-based techniques. Several post-transcriptional and post-translational modifications have also been proposed. However, the efficacy and long-term side effects of these modalities have yet to be verified. Currently, cell therapy can be employed in combination with conventional treatment and could be used for HD in which the structural and functional restoration of degenerated neurons can occur. Several animal models have been established recently to develop cell-based therapies using renewable cell sources such as embryonic stem cells, induced pluripotent stem cells, mesenchymal stromal cells, and neural stem cells. These models face numerous challenges in translation into clinics. Nevertheless, investigations in Advanced Therapy Medicinal Products (ATMPs) open a promising window for HD research and their clinical application. In this study, the ATMPs entry pathway in HD management was highlighted, and their advantages and disadvantages were discussed.

Traffic light at DSB-transit regulation between gene transcription and DNA repair

Transcription of actively expressed genes is dampened for kilobases around DNA lesions via chromatin modifications. This is believed to favour repair and prevent genome instability. Nonetheless, mounting evidence suggests that transcription may be induced by DNA breakage, resulting in the local de novo synthesis of non-coding RNAs (ncRNAs). Such transcripts have been proposed to play important functions in both DNA damage signalling and repair. Here, we review the recently identified mechanistic details of transcriptional silencing at damaged chromatin, highlighting how post-translational histone modifications can also be modulated by the local synthesis of DNA damage-induced ncRNAs. Finally, we envision that these entangled transcriptional events at DNA breakages can be targeted to modulate DNA repair, with potential implications for locus-specific therapeutic strategies.

Retinal Organoids from Induced Pluripotent Stem Cells of Patients with Inherited Retinal Diseases: A Systematic Review

BACKGROUND

Currently, most inherited retinal diseases lack curative interventions, and available treatment modalities are constrained to symptomatic approaches. Retinal organoid technology has emerged as a method for treating inherited retinal diseases, with growing academic interest in recent years. The purpose of this review was to systematically organize the current protocols for generating retinal organoids using induced pluripotent stem cells from patients with inherited retinal disease and to investigate the application of retinal organoids in inherited retinal disease research.

METHODS

Data were collected from the PubMed, Scopus, and Web of Science databases using a keyword search. The main search term used was "retinal organoid," accompanied by secondary keywords such as "optic cup," "three-dimensional," and "self-organizing." The final search was conducted on October 2, 2024.

RESULTS

Of the 2,129 studies retrieved, 130 were included in the qualitative synthesis. The protocols for the generation of retinal organoids in inherited retinal disease research use five major approaches, categorized into 3D and a combination of 2D/3D approaches, implemented with modifications. Disease phenotypes have been successfully reproduced via the generation of retinal organoids from the induced pluripotent stem cells of individuals with inherited retinal diseases, facilitating the progression of research into novel therapeutic developments. Cells have been obtained from retinal organoids for cell therapy, and progress toward their potential integration into clinical practice is underway. Considering their potential applications, retinal organoid technology has shown promise across various domains.

CONCLUSION

In this systematic review, we organized protocols for generating retinal organoids using induced pluripotent stem cells from patients with inherited retinal diseases. Retinal organoid technology has various applications including disease modeling, screening for novel therapies, and cell replacement therapy. Further advancements would make this technology a clinically significant tool for patients with inherited retinal diseases.

Current and Future Roles of Chimeric Antigen Receptor T-Cell Therapy in Neurology: A Review

Importance

Advancements in molecular engineering have facilitated the creation of engineered T cells that express synthetic receptors, termed chimeric antigen receptors (CARs). This is promising not only in cancer treatment but also in addressing a spectrum of other conditions. This review provides a comprehensive overview of the current approaches and future potential of CAR T-cell therapy in the field of neurology, particularly for primary brain tumors and autoimmune neurological disorders.

Observations

CAR T-cell therapy for glioblastoma is promising; however, first-in-human trials did not yield significant success or showed only limited success in a subset of patients. To date, the efficacy of CAR T-cell therapies has been demonstrated in animal models of multiple sclerosis, but larger human studies to corroborate the efficacy remain pending. CAR T cells showed efficacy in treatment of patients with relapsed or refractory aquaporin 4-immunoglobulin G-seropositive neuromyelitis optica spectrum disorders. Further studies with larger patient populations are needed to confirm these results. Success was reported also for treatment of cases with generalized myasthenia gravis using CAR T cells. Chimeric autoantibody receptor T cells, representing a modified form of CAR T cells directed against autoreactive B cells secreting autoantibodies, were used to selectively target autoreactive anti-N-methyl-d-aspartate B cells under in vitro and in vivo conditions, providing the basis for human studies and application to other types of autoimmune encephalitis associated with neuronal or glial antibodies.

Conclusions and Relevance

CAR T cells herald a new era in the therapeutic landscape of neurological disorders. While their application in solid tumors, such as glioblastoma, has not universally yielded robust success, emerging innovative strategies show promise, and there is optimism for their effectiveness in certain autoimmune neurological disorders.

Molecular Programming Design of Glyconucleic Acid Aptamer with High Stability

Functional nucleic acids (FNAs), possessing specific biological functions beyond their informational roles, have gained widespread attention in disease therapeutics. However, their clinical application is severely limited by their low serum stability in complex physiological environments. In this work, a precise molecular programming strategy is explored to prepare glyconucleic acid aptamers (GNAAs) with high serum stability. Four glyconucleic acid modules compatible with commercial solid-phase synthesis are designed and synthesized. Through precise molecular design, the accurate modification of four different carbohydrate ligands at specific sites of DNA aptamers is achieved. It is demonstrated that glycosylation modification can significantly increase DNA aptamers' serum stability while maintaining their structures and high affinity. The stabilization effect is superior to that of currently commonly used commercial chemical modifications. Moreover, it is confirmed that this approach displays insignificant effects on the DNA aptamers' tumor-targeting ability and metabolism in vivo. This method offers a simple, economical, and efficient strategy for precise glycosylation modification of nucleic acids. This allows to prepare glycosyl functional nucleic acids with high serum stability, which can expand the application scope of functional nucleic acids and promote the practical transformation of functional nucleic acids.

Circular RNAs in laryngeal cancer

Laryngeal cancer remains a significant global health concern, with poor prognosis for advanced-stage disease highlighting the need for novel diagnostic, prognostic, and therapeutic approaches. Circular RNAs (circRNAs), a class of covalently closed non-coding RNAs, have emerged as important regulators of gene expression and cellular processes in various cancers, including laryngeal cancer. This review summarizes the current understanding of circRNAs in laryngeal cancer, covering their biogenesis, regulatory mechanisms, and potential clinical applications. We explore the diverse functions of circRNAs, including their roles as miRNA sponges, protein interactors, and direct mRNA regulators, and their influence on key cellular processes such as proliferation, invasion, and metastasis. The review highlights promising circRNAs as diagnostic and prognostic biomarkers, as well as potential therapeutic targets. We also outline current strategies for circRNA modulation, including suppression techniques like RNA interference and CRISPR/Cas systems, and overexpression methods using vectors and synthetic circRNAs.

Identification of cell type-specific cell-penetrating peptides through in vivo phage display leveraged by next generation sequencing

Vascular anomalies (VA) refer to abnormal blood or lymphatic vessel architecture, most often as a result of dysregulated growth. Venous malformations (VM), a subgroup of VAs, are triggered by activating mutations in the Angiopoietin/TIE2-PI3K/AKT/mTOR signaling pathway with TIE2 L914F (gene name TEK) being one of the most frequent mutations in patients with VMs. Although systemic targeting of the overactivated pathway is possible, it would be a therapeutic advantage to restrict treatment to only the affected lesions. To identify peptides with potential selective binding to TIE2 L914F lesions we applied in vivo phage display to TIE2 L914F-overexpressing endothelial cells (ECs) in a subcutaneous matrigel xenograft mouse model of VMs. By panning for lesion-targeting phages in combination with subcellular fractionation, a screen for cell-penetrating candidate phages was established. Employing Next Generation Sequencing (NGS) and a refined bioinformatic analysis we were able to identify many novel cell-penetrating peptides (CPPs). To pinpoint the most selective and viable CCP candidates a hierarchical clustering algorithm was utilized. This method aggregated CPPs with highly similar sequences into a small number of clusters from which consensus sequences could be derived. Selected candidate CPPs exhibited uptake in TIE2 L914F-expressing human umbilical vein endothelial cells (HUVEC) in culture and were able to deliver siRNA into these cells. In conclusion, our NGS bioinformatic-supported approach led to the identification of novel and selective CPPs capable of transporting a siRNA cargo into targeted cells.

How can MSI enhance our understanding of ASO distribution?

In the dynamic field of drug discovery and development, a comprehensive understanding of drug absorption, distribution, metabolism, excretion, and toxicity is crucial. Mass spectrometry imaging (MSI) has become a key analytical tool in the pharmaceutical industry, allowing evaluation of drug biodistribution and molecular profiles. Antisense oligonucleotides (ASOs) are emerging drug candidates for treating neurologic diseases. This review explores the potential of MSI in investigating ASOs' spatial distribution within neurological disease models. Here, we focus on multimodal molecular imaging to gain insights into ASO distribution, simultaneously with a better understanding of the molecular pathways affected by ASOs. An improved understanding of therapeutic ASOs in tissue will potentially improve neurologic therapies, emphasizing their importance in patient care.

The state-of-the-art of N-of-1 therapies and the IRDiRC N-of-1 development roadmap

In recent years, a small number of people with rare diseases caused by unique genetic variants have been treated with therapies developed specifically for them. This pioneering field of genetic N-of-1 therapies is evolving rapidly, giving hope for the individualized treatment of people living with very rare diseases. In this Review, we outline the concept of N-of-1 individualized therapies, focusing on genetic therapies, and illustrate advances and challenges in the field using cases for which therapies have been successfully developed. We discuss why the traditional drug development and reimbursement pathway is not fit for purpose in this field, and outline the pragmatic, regulatory and ethical challenges this poses for future access to N-of-1 therapies. Finally, we provide a roadmap for N-of-1 individualized therapy development.

Mitigating off-target effects of small RNAs: conventional approaches, network theory and artificial intelligence

Three types of highly promising small RNA therapeutics, namely, small interfering RNAs (siRNAs), microRNAs (miRNAs) and the RNA subtype of antisense oligonucleotides (ASOs), offer advantages over small-molecule drugs. These small RNAs can target any gene product, opening up new avenues of effective and safe therapeutic approaches for a wide range of diseases. In preclinical research, synthetic small RNAs play an essential role in the investigation of physiological and pathological pathways as silencers of specific genes, facilitating discovery and validation of drug targets in different conditions. Off-target effects of small RNAs, however, could make it difficult to interpret experimental results in the preclinical phase and may contribute to adverse events of small RNA therapeutics. Out of the two major types of off-target effects we focused on the hybridization-dependent, especially on the miRNA-like off-target effects. Our main aim was to discuss several approaches, including sequence design, chemical modifications and target prediction, to reduce hybridization-dependent off-target effects that should be considered even at the early development phase of small RNA therapy. Because there is no standard way of predicting hybridization-dependent off-target effects, this review provides an overview of all major state-of-the-art computational methods and proposes new approaches, such as the possible inclusion of network theory and artificial intelligence (AI) in the prediction workflows. Case studies and a concise survey of experimental methods for validating in silico predictions are also presented. These methods could contribute to interpret experimental results, to minimize off-target effects and hopefully to avoid off-target-related adverse events of small RNA therapeutics. LINKED ARTICLES: This article is part of a themed issue Non-coding RNA Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v182.2/issuetoc.

Endosomal Escape and Nuclear Localization: Critical Barriers for Therapeutic Nucleic Acids

Therapeutic nucleic acids (TNAs) including antisense oligonucleotides (ASOs) and small interfering RNA (siRNA) have emerged as promising treatment strategies for a wide variety of diseases, offering the potential to modulate gene expression with a high degree of specificity. These small, synthetic nucleic acid-like molecules provide unique advantages over traditional pharmacological agents, including the ability to target previously "undruggable" genes. Despite this promise, several biological barriers severely limit their clinical efficacy. Upon administration, TNAs primarily enter cells through endocytosis, becoming trapped inside membrane-bound vesicles known as endosomes. Studies estimate that only 1-2% of TNAs successfully escape endosomal compartments to reach the cytosol, and in some cases the nucleus, where they bind target mRNA and exert their therapeutic effect. Endosomal entrapment and inefficient nuclear localization are therefore critical bottlenecks in the therapeutic application of TNAs. This review explores the current understanding of TNA endosomal escape and nuclear transport along with strategies aimed at overcoming these challenges, including the use of endosomal escape agents, peptide-TNA conjugates, non-viral delivery vehicles, and nuclear localization signals. By improving both endosomal escape and nuclear localization, significant advances in TNA-based therapeutics can be realized, ultimately expanding their clinical utility.

3D and 4D printing of MXene-based composites: from fundamentals to emerging applications

The advent of three-dimensional (3D) and four-dimensional (4D) printing technologies has significantly improved the fabrication of advanced materials, with MXene-based composites emerging as a particularly promising class due to their exceptional electrical, mechanical, and chemical properties. This review explores the fundamentals of MXenes and their composites, examining their unique characteristics and the underlying principles of their synthesis and processing. We highlight the transformative potential of 3D and 4D printing techniques in tailoring MXene-based materials for a wide array of applications. In the field of tissue regeneration, MXene composites offer enhanced biocompatibility and mechanical strength, making them ideal for scaffolds and implants. For drug delivery, the high surface area and tunable surface chemistry of MXenes enable precise control over drug release profiles. In energy storage, MXene-based electrodes exhibit superior conductivity and capacity, paving the way for next-generation batteries and supercapacitors. Additionally, the sensitivity and selectivity of MXene composites make them excellent candidates for various (bio)sensing applications, from environmental monitoring to biomedical diagnostics. By integrating the dynamic capabilities of 4D printing, which introduces time-dependent shape transformations, MXene-based composites can further adapt to complex and evolving functional requirements. This review provides a comprehensive overview of the current state of research, identifies key challenges, and discusses future directions for the development and application of 3D and 4D printed MXene-based composites. Through this exploration, we aim to underscore the significant impact of these advanced materials and technologies on diverse scientific and industrial fields.

Quantifying and mitigating motor phenotypes induced by antisense oligonucleotides in the central nervous system

Antisense oligonucleotides (ASOs) are emerging as a promising class of therapeutics for neurological diseases. When injected directly into cerebrospinal fluid, ASOs distribute broadly across brain regions and exert long-lasting therapeutic effects. However, many phosphorothioate (PS)-modified gapmer ASOs show transient motor phenotypes when injected into the cerebrospinal fluid, ranging from reduced motor activity to ataxia or acute seizure-like phenotypes. Using a behavioral scoring assay customized to reflect the timing and nature of these effects, we show that both sugar and phosphate modifications influence acute motor phenotypes. Among sugar analogs, DNA induces the strongest motor phenotypes while 2'-substituted RNA modifications improve the tolerability of PS ASOs. Reducing the PS content of gapmer ASOs, which contain a stretch of PS-DNA, improves their toxicity profile, but in some cases also reduces efficacy or duration of effect. We show that this acute toxicity is not mediated by major nucleic acid sensing immune pathways. Formulating ASOs with divalent ions before injection and avoiding phosphate-based buffers modestly improved tolerability through mechanisms at least partially distinct from reduced PS content. Overall, our work identifies and quantifies an understudied aspect of oligonucleotide toxicology in the CNS, explores its mechanism, and presents platform-level medicinal chemistry and formulation approaches that improve tolerability of this class of compounds.

Unraveling the role of long non-coding RNAs in therapeutic resistance in acute myeloid leukemia: New prospects & challenges

Acute Myeloid Leukemia (AML) is a fatal hematological disease characterized by the unchecked proliferation of immature myeloid blasts in different tissues developed by various mutations in hematopoiesis. Despite intense chemotherapeutic regimens, patients often experience poor outcomes, leading to substandard remission rates. In recent years, long non-coding RNAs (lncRNAs) have increasingly become important prognostic and therapeutic hotspots, due to their contributions to dysregulating many functional epigenetic, transcriptional, and post-translational mechanisms leading to alterations in cell expressions, resulting in increased chemoresistance and reduced apoptosis in leukemic cells. Through this review, I highlight and discuss the latest advances in understanding the major mechanisms through which lncRNAs confer therapy resistance in AML. In addition, I also provide perspective on the current strategies to target lncRNA expressions. A better knowledge of the critical role that lncRNAs play in controlling treatment outcomes in AML will help improve existing medications and devise new ones.

Effective inhibition of dengue virus replication using 3'UTR-targeted Vivo-Morpholinos

Introduction

Due to the impact of antibody-dependent enhancement and viral variation, effective vaccines or antiviral therapies remain lacking for the dengue virus (DENV). Nucleic acid drugs, particularly Vivo-Morpholinos (MOs), have emerged as a promising avenue for antiviral treatment due to their programmability and precise targeting, as well as their safety and stability.

Method

In this study, we designed and developed 10 morpho-modified (octa-guanidine dendrimer) vivo-MO molecules that target each coding gene of DENV. Subsequently, we assessed the inhibitory impact of vivo-MOs on dengue viral RNA load utilizing qRT-PCR. Furthermore, we examined the inhibitory effect on the live virus through a plaque assay and the TCID50 assay.

Results

We found that the vivo-3'UTR molecule targeting the 3' untranslated region of the dengue virus exhibited the highest inhibitory rate against viral load. The vivo-3'UTR demonstrated 99% inhibition of dengue virus RNA and the inhibition of up to 98% of the live virus. Additionally, the targeted sequence was conserved among all four DENV serotypes, and treatment with 10 μM of vivo-3'UTR resulted in a reduction of viral titers for all four DENV serotypes by over 99.99%. Additionally, we revealed that pre-treatment with vivo-3'UTR had a notable preventive effect against viral infection.

Conclusion

This study screened an effective vivo-MO target drug for the treatment of dengue virus infection, demonstrating low toxicity in mammalian cell lines, and proposed a novel preventive antiviral approach.

Prions: structure, function, evolution, and disease

Prions are proteinaceous infectious particles implicated in fatal neurodegenerative disorders known as prion diseases. Herein, we provide an overview of prion biology, emphasizing the structural, functional, and evolutionary aspects of prions, along with their potential applications in protein engineering. Understanding the structure-function relationships of both healthy and disease-associated prion proteins enables a deeper understanding of the mechanisms of prion-induced neurotoxicity. Furthermore, we describe how insights into prion evolution have begun to shed light on their ancient origins and evolutionary resilience, offering deeper insights into the potential roles of prions in primordial chemical processes.

Large- and Small-Animal Studies of Safety, Pharmacokinetics, and Biodistribution of Inflammasome-Targeting Nanoligomer in the Brain and Other Target Organs

Immune malfunction or misrecognition of healthy cells and tissue, termed autoimmune disease, is implicated in more than 80 disease conditions and multiple other secondary pathologies. While pan-immunosuppressive therapies like steroids can offer limited relief for systemic inflammation for some organs, many patients never achieve remission, and such drugs do not cross the blood-brain barrier, making them ineffective for tackling neuroinflammation. Especially in the brain, unintended activation of microglia and astrocytes is hypothesized to be directly or indirectly responsible for multiple sclerosis, amyotrophic lateral sclerosis, Parkinson's disease, and Alzheimer's disease. Recent studies have also shown that targeting inflammasomes and specific immune targets can be beneficial for these diseases. Furthermore, our previous studies have shown targeting NF-κB and NLRP3 through brain penetrant Nanoligomer cocktail SB_NI_112 (abbreviated as NI112) can be therapeutic for several neurodegenerative diseases. Here, we show safety-toxicity studies, followed by pharmacokinetics and biodistribution in small- (mice) and large-animal (dog) studies of this inflammasome-targeting Nanoligomer cocktail NI112. We conducted studies using four different routes of administration: intravenous, subcutaneous, intraperitoneal, and intranasal, and identified the drug concentration over time using inductively coupled plasma mass spectrometry in the blood serum, the brain (including different brain regions), and other target organs such as liver, kidney, and colon. Our results indicate that the Nanoligomer cocktail has a strong safety profile and shows high biodistribution (F ∼ 0.98) and delivery across multiple routes of administration. Further analysis showed high brain bioavailability with a ratio of NI112 in brain tissue to blood serum of ∼30%. Our model accurately shows dose scaling, translation between different routes of administration, and interspecies scaling. These results provide an excellent platform for human clinical translation and prediction of therapeutic dosage between different routes of administration.

Molecular Profiling of Mouse Models of Loss or Gain of Function of the KCNT1 (Slack) Potassium Channel and Antisense Oligonucleotide Treatment

The potassium sodium-activated channel subtype T member 1 (KCNT1) gene encodes the Slack channel KNa1.1, which is expressed in neurons throughout the brain. Gain-of-function variants in KCNT1 are associated with a spectrum of epilepsy syndromes, and mice carrying those variants exhibit a robust phenotype similar to that observed in patients. Kcnt1 knockout (KO) mice, however, have a normal lifespan without any epileptic phenotype. To understand the molecular differences between these two models, we conducted a comprehensive proteomic analysis of the cerebral cortices of Kcnt1 KO and Kcnt1R455H/+ mice, an animal model bearing a cytoplasmic C-terminal mutation homologous to a human R474H variant that results in EIMFS. The greatest change observed in Kcnt1 KO mice compared to the wild-type mice was the increased expression of multiple proteins of the inner mitochondrial membrane. Electron microscopy studies of cortical mitochondria from Kcnt1 KO mice further confirmed a significant increase in the density of mitochondrial cristae compared to that in wild-type mice. Kcnt1 reduction by a murine-specific Kcnt1 antisense oligonucleotide (ASO) in Kcnt1R455H/+ mice partially corrected the proteomic dysregulations in the disease model. The results support the hypothesis that ASO-mediated KCNT1 reduction could be therapeutically useful in the treatment of KCNT1 epilepsies.

Exploring the role of pericardial miRNAs and exosomes in modulating cardiac fibrosis

The potential of the pericardial space as a therapeutic delivery tool for cardiac fibrosis and heart failure (HF) treatment has yet to be elucidated. Recently, miRNAs and exosomes have been discovered to be present in human pericardial fluid (PF). Novel studies have shown characteristic human PF miRNA compositions associated with cardiac diseases and higher miRNA expressions in PF compared to peripheral blood. Five key studies found differentially expressed miRNAs in HF, angina pectoris, aortic stenosis, ventricular tachycardia, and congenital heart diseases with either atrial fibrillation or sinus rhythm. As miRNA-based therapeutics for cardiac fibrosis and HF showed promising results in several in vivo studies for multiple miRNAs, we hypothesize a potential role of miRNA-based therapeutics delivered through the pericardial cavity. This is underlined by the favorable results of the first phase 1b clinical trial in this emerging field. Presenting the first human miRNA antisense drug trial, inhibition of miR-132 by intravenous administration of a novel antisense oligonucleotide, CDR132L, established efficacy in reducing miR-132 in plasma samples in a dose-dependent manner. We screened the literature, provided an overview of the miRNAs and exosomes present in PF, and drew a connection to those miRNAs previously elucidated in cardiac fibrosis and HF. Further, we speculate about clinical implications and potential delivery methods.