Development of Dynamic Liquid and Conjugated Electrospun Poly(L-lactide-co-caprolactone)/Collagen Nanoyarns for Regulating Vascular Smooth Muscle Cells Growth.

Simulating the modeling of smooth muscle layer in the vascular structure makes a great difference for vascular tissue regeneration. A functional tissue engineered vascular media shall promote the aligned organization and three-dimensional penetration of smooth muscle cells (SMCs) into the scaffold. To this aim, dynamic liquid and conjugated nanoyarns based on poly(L-lactide-co-caprolactone) (P(LLA-CL)) and collagen (COL) with a weight ratio at 3:1 were fabricated by electrospinning methods, with random and aligned nanofibers as control groups. The Fourier transform infrared spectroscopy and X-ray diffraction analyses confirmed the preservation of P(LLA-CL)/COL components and structure. Scanning electron microscope (SEM) results indicated a significant increase of yarn diameters at 19.27 ± 6.16 μm (dynamic liquid) and 10.24 ± 3.09 μm (conjugated), and both of the nanoyarns had improved mechanical tensile properties than the random nanofibers. Compared with random and aligned nanofibers, the nanoyarns presented significant higher porosity and larger pore diameter, leading to a decrease of water contact angle and a promotion of SMCs proliferation and migration. Better SMCs orientation was observed on the conjugated nanoyarns, while superior SMCs penetration was achieved on the dynamic liquid nanoyarns, owing to the differences in yarns microstructure. Herein, this study demonstrated that the aligned and porous P(LLA-CL)/COL nanoyarns fabricated by dynamic liquid and conjugated electrospinning were beneficial to regulating vascular SMCs outgrowth, which had important implications for functional reconstruction of vascular media.