Conductive Nerve Guidance Conduits Based on Morpho Butterfly Wings for Peripheral Nerve Repair

Abstract

Peripheral nerve injury (PNI), causing loss of sensory and motor function, is a complex and challenging disease in the clinic due to the restricted regeneration capacity. Nerve guidance conduits (NGCs) have become a promising substitute for peripheral nerve regeneration, but their efficacy is often limited. Here, inspired by the physiological structures of peripheral nerves, we present a conductive topological scaffold for nerve repair by modifying Morpho butterfly wing with reduced graphene oxide (rGO) nanosheets and methacrylated gelatin (GelMA) hydrogel encapsulated brain-derived neurotrophic factor (BDNF). Benefiting from the biocompatibility of GelMA hydrogel, the conductivity of rGO and parallel nanoridge structures of wing scales, PC12 cells, and neural stem cells grown on the modified wing have an increased neurite length with guided cellular orientation. In addition, the NGCs are successfully obtained by manually rolling up the scaffolds and exhibited great performance in repairing 10 mm sciatic nerve defects in rats, and we believe that the NGCs can be applied in reparing longer nerve defects in the future by further optimization. We also demonstrate the feasibility of electrically conductive NGCs based on the rGO/BDNF/GelMA-integrated Morpho butterfly wing as functional nerve regeneration conduits, which may have potential value for application in repairing peripheral nerve injuries.

Progress in Gelatin as Biomaterial for Tissue Engineering

“…Despite the fact that gelatin is not a conductive material, it has also been part of conductive hydrogels. As it is a naturally derived material, it confers highly desirable improvements in electrically active elements such as biocompatibility or cell adhesion, which otherwise are lacking in these hydrogels [77,78]. For instance, Hu et al designed a conductive hydrogel for peripheral nerve reconstruction.…”

“…Conductivity was achieved by using graphene oxide, while biocompatibility and cell adhesion properties were improved by gelatin. A further advantage was the steady release of growth factors that enhanced cell growth [77].…”

“…These constructs were simple and yet effective hydrogels that allowed for the controlled release of growth factors such as BMP-2 or TGF-β1 for bone regeneration [24,[83][84][85]. Subsequently, these biomaterial-derivative platforms were widely employed for the renewal of a myriad of tissues such as myocardial, nerve or wounds because of gelatin's ability to release diverse biological elements [77,[86][87][88]. Nonetheless, in the search to find a synergistic effect, a forefront strategy relies on combining different therapeutic agents in the same delivery system (known as dual delivery platforms) [89].…”

Kölliker’s organ-supporting cells and cochlear auditory development

“…In the future, there is still a need to optimize the conditions of mouse inner ear stem cell isolated culture and proliferation, to establish a safe and efficient technology system for differentiation of inner ear stem cells into mature hair cells (Wei et al, 2021 ; Guo et al, 2022 ; Hu et al, 2022 ; Tao et al, 2022 ), to screen mouse stem cell lines that can be used for stem cell therapy (Liu et al, 2018 ; Tang et al, 2019 ); discovering new molecular markers specific for inner ear hair cells and their precursor cells (Qi et al, 2019 ), thus providing conditions for the establishment of rapid and non-destructive cell identification and sorting techniques, and thus laying a solid theoretical foundation and providing technical support for stem cell therapy for sensorineural deafness technical support.…”

Physical Cue‐Based Strategies on Peripheral Nerve Regeneration

“…[5][6][7] Moreover, neurotropism of peripheral nerves, i.e., lack or directionless guidance, will result in incomplete peripheral nerve regeneration (PNR), neuroma formation, and even regeneration failure. [5] Traditional methods of surgery such as neurorrhaphy, nerve autograft, and nerve allograft are constrained by deleterious nerve tension, limited donors, donor sites with dysfunction, and undesirable immune response. [8,9] Pharmacotherapy and structural-unmodified nerve scaffold failed with low drug half-life and inadequate traction effect, respectively, and consequently unsatisfactory therapeutic effects are declining in popularity.…”