Modulation of the miR-485-3p/PGC-1α Pathway by ASO-Loaded Nanoparticles Attenuates ALS Pathogenesis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive motor neuron degeneration with limited treatment options. In this study, we investigated the pathological role of microRNA-485-3p (miR-485-3p) in ALS, particularly its regulation of PGC-1α, a transcriptional coactivator essential for mitochondrial function and neuroprotection. We also evaluated the therapeutic potential of BMD-001S, a nanoparticle-based formulation encapsulating an antisense oligonucleotide targeting miR-485-3p. Our results demonstrated that miR-485-3p expression was significantly elevated in both SOD1^G93A-expressing HMC3 microglial cells and in the spinal cords of SOD1^G93A transgenic mice at late disease stages, implicating its contribution to ALS pathogenesis. Intravenous administration of BMD-001S effectively reduced miR-485-3p levels and restored <i>PGC-1α</i> mRNA and PGC-1α protein expression in the spinal cord. These molecular changes were associated with notable therapeutic outcomes, including reduced SOD1 protein aggregation, decreased neuroinflammation, and lower neurofilament light chain concentrations in cerebrospinal fluid. Moreover, BMD-001S treatment was associated with improvements in electrophysiological parameters and preservation of neuromuscular junction integrity during the observation period in SOD1^G93A transgenic mice. Taken together, these findings suggest that miR-485-3p/PGC-1α pathway is a promising therapeutic target in ALS and support the potential of BMD-001S as a novel treatment strategy for the disease.