Fortifying Angiogenesis in Ischemic Muscle with FGF9-Loaded Electrospun Poly(Ester Amide) Fibers

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Vascular Biology

Background:

• Angiogenic growth factor delivery has limited efficacy in peripheral vascular disease patients.
• Enhancing mural cell coverage of microvessels is a promising alternative strategy.
• Sustained delivery platforms are crucial for effective microvascular regeneration.

Purpose of the Study:

• To fabricate electrospun poly(ester amide) (PEA) nanofiber mats for sustained delivery of fibroblast growth factor 9 (FGF9).
• To evaluate the efficacy of FGF9-loaded PEA mats in promoting angiogenesis and microvascular remodeling in preclinical models of hindlimb ischemia.

Main Methods:

• Fabrication of electrospun PEA nanofiber mats loaded with FGF9.
• In ovo chick chorioallantoic membrane assay with 3D power Doppler micro-ultrasound imaging.
• Implantation of FGF9-loaded PEA mats onto the tibialis anterior muscle in a mouse model of hindlimb ischemia.

Main Results:

• PEA fiber mats successfully delivered FGF9, enhancing angiogenesis and mural cell coverage up to 28 days post-implantation.
• FGF9 treatment led to near-normal myofiber size and reduced fibrosis in regenerating muscle.
• Mice with FGF9-loaded PEA mats showed improved locomotion compared to controls.

Conclusions:

• Locally released FGF9 from PEA nanofibers promotes microvascular remodeling.
• This approach offers a promising strategy for improving muscle health in peripheral vascular disease.
• Sustained delivery of FGF9 via PEA nanofibers represents a viable therapeutic avenue for vascular regeneration.