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Bagaric, R. M.

Publications and source records attributed to Bagaric, R. M..

2 recordsLinked to original sources

Moderate-term dimethyl fumarate treatment reduces pathology of dystrophic skeletal and cardiac muscle in a mouse model

In Duchenne muscular dystrophy (DMD), corticosteroids significantly slow disease progression and have been used as a standard of care tool for more than 30 years. However, corticosteroids also impart side effects severe enough to preclude use in some patients. There remains an unmet need for new therapeutics that target the flow-on pathogenic mechanisms of DMD with a more favourable side-effect profile. We have previously demonstrated that short-term treatment with dual-purpose anti-inflammatory, anti-oxidative dimethyl fumarate (DMF), a drug with indication and established safety data in Multiple Sclerosis, more selectively modulates Duchenne (mdx) immunology than the frequently used corticosteroid, prednisone (PRED). Here, we assess the effect of moderate-term DMF treatment over 5 weeks in the typically mild mdx mouse model that we aggravated using exercise. We show that like PRED, DMF maintains anti-inflammatory action but with additional anti-fibrotic and anti-lipogenic effects on muscle with moderate-term use. This study supports our previous work highlighting DMF as a possible repurposing candidate for DMD, especially for patients who cannot tolerate chronic corticosteroid treatment.

pathology↗

Dimethyl fumarate modulates the Duchenne muscular dystrophy disease program following short-term treatment in mdx mice

New medicines are urgently required to treat the fatal neuromuscular disease, Duchenne muscular dystrophy (DMD). DMD involves progressive muscle damage and weakness, which are preceded by oxidative stress, inflammation, and mitochondrial dysfunction. Dimethyl fumarate (DMF) is a potent small molecule nuclear erythroid 2-related factor 2 (Nrf2) activator with current clinical utility in the treatment of multiple sclerosis and psoriasis. Pharmaceutical targeting of Nrf2 by DMF has strong translational potential for DMD, given it: (1) promotes antioxidant defence systems; (2) has a potent immuno-modulatory profile; and (3) can be rapidly re-purposed into clinical care strategies for DMD patients. Here, we tested two weeks of daily 100mg/kg DMF versus 5mg/kg standard care prednisone (PRED) treatment during the peak muscle degeneration period in juvenile mdx mice, the gold standard murine DMD model. Both drugs modulated seed genes driving the DMD disease program and improved muscle force production in fast-twitch muscle. However, only DMF showed pro-mitochondrial effects that protected contracting muscles from fatigue, improved histopathology and augmented clinically compatible muscle function tests. In contrast, PRED treatment stunted mouse growth, worsened histopathology and modulated many normally expressed inflammatory and extracellular matrix (ECM) genes consistent with pan immunosuppression. These findings suggest DMF could be a more selective modulator of the DMD disease program with better efficacy and fewer side effects than standard care PRED therapy warranting follow-up studies to progress clinical translation.

pathology↗