The nerve tissue
consists of aligned
fibrous nerve bundles, in which neurons communicate and transmit information
through electrical signals. Hence, biocompatibility, oriented fibrous
structure, and electrical conductivity are key factors for the biomimetic
design of nerve scaffolds. Herein, we built a technical platform to
combine electrospinning and electrospraying for preparing a biomimetic
scaffold with conductivity and aligned fibrous structure. The highly
aligned polycaprolactone (PCL) microfibrous scaffolds with co-sprayed
collagen and conductive polypyrrole nanoparticles (PPy NPs) showed
good bioactivity, supplying a platform for exploring the effects of
topographical guidance, fiber conductivity, and its mediated external
electrical signals on neurogenesis. The results revealed that collagen-coated
highly aligned PCL microfibrous scaffold induced PC12 cells oriented
and elongated along the direction of fibers. In addition, the improved
conductivity of PPy-coated aligned fibers and its mediated external
electrical stimulation collectively contributed to the functional
expression, including elongation, gene expression, and protein expression,
of PC12 cells. We further demonstrated the potential mechanism where
the fiber conductivity and its mediated external electrical signals
resulted in the upregulation of voltage-gated calcium channel, leading
to the influx of Ca2+, thereby activating intracellular
signaling cascades, ultimately enhancing neurogenesis. This approach
provides a strategy to design aligned fibrillary scaffolds with bioactive
adhesion domains and electroconductivity for neural regeneration.