Duchenne Muscular Dystrophy (DMD) is the most common form of muscular dystrophy, affecting 20,000 children worldwide yearly. Muscle degenerative conditions, including the genetic disorder DMD and age-related sarcopenia, share pathological mechanisms such as progressive muscle wasting and elevated myostatin signaling. Existing therapies rely on systemic drug administration or gene-based approaches, which can take years to develop. They also raise safety concerns, costs, and a lack of a long-term solution. We propose using the chassis Limosilactobacillus reuteri (formerly Lactobacillus reuteri) as a gut-safe probiotic. Elevated interleukin-6 (IL-6), a cytokine released during inflammation and muscle stress, signals disease activity. Our system uses an IL-6-responsive promoter to detect this state and drive FST-344 (a specific follistatin protein used) expression. The resulting follistatin protein suppresses myostatin signaling by preventing receptor binding, thereby promoting muscle preservation. To ensure homeostatic control and prevent overproduction, the circuit incorporates a TetR-regulated repression loop. For additional biosafety and regulatory control, the design incorporates a mazF-based kill switch and a feedback mechanism to limit expression and trigger cell termination. This oral, sensor-regulated delivery system offers a potentially scalable, noninvasive, and adaptable alternative to traditional gene therapies and systemic drug regimens.