Nerve regeneration materials

Current polymeric entubulization repair methods for peripheral nerve regeneration use various nondegradable and biodegradable materials. The most common nondegradable material investigated has been silicone rubber. Medical grade silicone rubber, polydimethylsiloxane, maintains its shape and can be filled with neurotrophic factors or extracellular... 

Polypyrrole composite biomaterials having electrically conductive properties have been prepared using hyaluronic acid or its sodium salt by galvanostatic and potentio-static methods. These agents are useful for preparing medical devices such as nerve and bone regeneration materials. 

From the description above we can deduce some functions that artificial implants must fulfill if they are to promote nerve regeneration in vivo. A general requirement of biocompatibility, which applies to materials implanted anywhere in the body, demands that the implanted construct must not induce inflammatory reactions or tumor formation and is not rejected or encapsulated by scar tissue. 

In conclusion, the chemical functionalization of synthetic materials with ECM molecules was an important step in the development of artificial implants with biological activities. Apart from these signals, which are always fixed to surfaces, peripheral nerve regeneration in vivo depends on a number of signals that are secreted from Schwann cells or the neurons themselves (Sect. 2.2). 

Dinis, T.M., Elia, R., Vidal, G., Auffret, A., Kaplan, D.L., Egles, C., 2014. Method to form a fiber/growth factor dual-gradient along electrospun silk for nerve regeneration. Acs Applied Materials and Interfaces 6 (19), 16817—16826. 

The high extent of axonal regeneration in the investigated crushed sciatic nerves, which have been contacted by such lyophilized chitosan membranes, indicates that chitosan acts as an inducer of nerve regeneration rather than just as a scaffold providing mechanical stabilization. The authors speculated that chitosan in these materials enhances Schwann cell proliferation, axon elongation and myelination. Additionally, silica ions may influence the... 

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