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Stoodley, J.

Publications and source records attributed to Stoodley, J..

3 recordsLinked to original sources

Dysregulated MEG3 in Myotonic Dystrophy 1: nuclear retention, pathological role, and therapeutic correction by antisense conjugates.

MEG3, a long non-coding RNA (lncRNA), has been shown to play a critical role in regulating apoptosis. Its downregulation inhibits apoptosis in cancer cells, whereas its upregulation has been associated with cell death in both cardiovascular disease and, more recently, Alzheimers Disease. Here we show that MEG3 is upregulated in Myotonic Dystrophy 1 (DM1). Specifically, we show MEG3 upregulation by several-fold in DM1 human muscle cells and in two DM1 mouse models, HSA-LR and LC15. In human DM1 muscle cells we observe nuclear retention of MEG3 and an increase in its transcript diversity. Furthermore, we observe a general trend of nuclear retention in DM1 affecting lncRNAs and microRNAs (miRNAs), in contrast to mRNAs, when compared to healthy cells. This altered nuclear retention may contribute to the pathological effects of non-coding RNA dysregulation in DM1. Importantly, we demonstrate that treatment with antisense conjugates targeting the repeat expansion causing DM1, an approach currently being tested in Clinical Trials, corrects MEG3 levels in HSA-LR mice, without additional therapeutic interventions targeting MEG3.

molecular biology↗

Type I PRMT inhibitor MS023 promotes SMN2 exon 7 inclusion and synergizes with nusinersen to rescue the phenotype of SMA mice

Spinal muscular atrophy (SMA) is the leading genetic cause of infant mortality. The advent of approved treatments for this devastating condition has significantly changed SMA patients life expectancy and quality of life. Nevertheless, these are not without limitations, and research efforts are underway to develop new approaches to be used alone and in combination, to ensure improved and long-lasting benefits for SMA patients. Protein arginine methyltransferases (PRMT) are emerging as druggable epigenetic targets, with several small molecule PRMT inhibitors already in clinical trial stage. From a screen of highly potent and selective next generation epigenetic small molecules, we have identified MS023, a potent and selective type I PRMT inhibitor, able to promote SMN2 exon 7 inclusion and increase SMN protein levels in preclinical SMA model, by inhibiting the binding of splicing factor hnRNPA1 to SMN2 pre-mRNA. Treatment of SMA mice with MS023 results in amelioration of the disease phenotype, with strong synergistic amplification of the positive effect when delivered in combination with the SMN2-targeting antisense oligonucleotide nusinersen. Moreover, transcriptomic analysis revealed that MS023 treatment has very minimal off-target effects and that the added benefit of the combination therapy is mainly attributable to targeting neuroinflammation. Our study warrants further clinical investigation of PRMT inhibition both as a stand-alone and add-on therapy for SMA patients.

neuroscience↗

Systemic antibody-oligonucleotide delivery to the central nervous system ameliorates mouse models of spinal muscular atrophy

Antisense oligonucleotides (ASOs) have emerged as one of the most innovative new genetic drug modalities, however, the high molecular weight limits their bioavailability for otherwise treatable neurological disorders. We investigated conjugation of ASOs to an antibody against the murine transferrin receptor (TfR), 8D3130, and evaluated it via systemic administration in mouse models of the neurodegenerative disease, spinal muscular atrophy (SMA). SMA like several other neurological and neuromuscular diseases, is treatable with single-stranded ASOs, inducing splice modulation of the survival motor neuron 2 (SMN2) gene. Administration of 8D3130-ASO conjugate resulted in bioavailability of 2.7% of the injected dose in brain. Additionally, 8D3130-ASO yielded therapeutically high levels of SMN2 splicing in the central nervous system of mildly affected adult SMA mice and resulted in extended survival of severe SMA mice. Systemic delivery of nucleic acid therapies with brain targeting antibodies offers powerful translational potential for future treatments of neuromuscular and neurodegenerative diseases.

molecular biology↗