Researchers used AAV vectors to deliver brain‑derived neurotrophic factor (BDNF) and GAS6 to muscle tissue in SOD1G93A mouse models of ALS and observed delayed symptom onset and slower disease progression. The dual‑factor, muscle‑directed gene therapy appears to provide retrograde neurotrophic support and modulate neuromuscular junction stability, offering a preclinical proof‑of‑concept for peripheral delivery strategies that target central neurodegeneration indirectly. Authors propose further optimization of dosing and biodistribution before translation to larger animal models.