Botulinum Toxin A Improves Supramuscular Fat Graft Retention by Enhancing Angiogenesis and Adipogenesis.

[BACKGROUND] Autologous fat grafting is commonly used for soft-tissue augmentation and reconstruction in plastic surgery. However, long-term graft retention rates are unpredictable, especially in muscle-related fat grafting.

[OBJECTIVE] To determine whether botulinum neurotoxin type A (BoNTA) may improve supramuscular fat grafting retention by reducing muscle movement, thereby enhancing angiogenesis and adipogenesis.

[MATERIALS AND METHODS] Pre-BTX+ nude mice were injected with BoNTA on the right quadriceps femoris and underwent supramuscular fat grafting 1 week later. BTX+ nude mice simultaneously underwent BoNTA injection and transplantation. Control nude mice underwent transplantation without BoNTA. Graft volumes were determined, and grafts underwent histological analyses and immunostaining. CatWalk XT gait analysis was conducted on BTX+ mice.

[RESULTS] Pre-BTX+ and BTX+ groups had significantly higher retention rates and exhibited better angiogenesis and adipocyte survival than the Control group.

[CONCLUSION] BoNTA injections improved the long-term retention of supramuscular fat grafts by reducing muscle movement, possibly by augmenting angiogenesis and adipogenesis.