An injectable, self-healing, electroconductive extracellular matrix-based hydrogel for enhancing tissue repair after traumatic spinal cord injury

Abstract

Injectable biomaterial-based treatment is a promising strategy to enhance tissue repair after traumatic spinal cord injury (SCI) by bridging cavity spaces. However, there are limited reports of injectable, electroconductive hydrogels with self-healing properties being employed for the treatment of traumatic SCI. Hence, a natural extracellular matrix (ECM) biopolymer (chondroitin sulphate and gelatin)-based hydrogel containing polypyrrole, which imparted electroconductive properties, is developed for traumatic SCI repair. The resulting hydrogels showed mechanical (~928 Pa) and conductive properties (4.49 mS/cm) similar to natural spinal cord tissues. Moreover, the hydrogels exhibited shear-thinning and self-healing abilities, which allows it to be effectively injected into the injury site and to fill the lesion cavity to accelerate the tissue repair of traumatic SCI. In vitro, electroconductive ECM hydrogels promoted neuronal differentiation, enhanced axon outgrowth, and inhibited astrocyte differentiation. The electroconductive ECM hydrogel activated endogenous neural stem cell neurogenesis in vivo (n = 6), and induced myelinated axon regeneration into the lesion site via activation of the PI3K/AKT and MEK/ERK pathways, thereby achieving significant locomotor function restoration in rats with spinal cord injury (p < 0.001, compared to SCI group). Overall, the injectable self-healing electroconductive ECM-based hydrogels developed in this study are ideal biomaterials for treatment of traumatic SCI.

N-carboxymethyl chitosan/sodium alginate composite hydrogel loading plasmid DNA as a promising gene activated matrix for in-situ burn wound treatment

“…The calculated maximum content of the Arg-CS/pDNA nanoparticles loaded in NCMC/SA scaffold was 21.9 μg/mg. The loading of plasmids by GAM could be realized in two ways [ [57] , [58] , [59] ]. The first approach was to integrate soluble plasmids with the scaffold by use of hydrogel swelling and water locking effect to load active factors.…”

Engineering Tissues of the Central Nervous System: Interfacing Conductive Biomaterials with Neural Stem/Progenitor Cells

“…Here, we provide a brief overview of these studies with a strong emphasis on those where conductive hydrogels have been investigated for NS/PC interfacing. For a detailed review on conductive hydrogel biomaterials, please see Xu et al [376] Graphene nanoparticles or powders have been incorporated into hydrogels made from various biomaterials, including collagen I, [377] gelatin, [289] alginate, [378] agarose, [379] silk, [380] chitosan, [381] polysaccharides, [382,383] and polyacrylamide, [375] by suspending graphene within the hydrogel solution prior to crosslinking. In both physically and covalently crosslinked hydrogels, increasing concentrations of graphene have been found to correlate with increased mechanical modulus and worsening cytocompatibility.…”

Antibacterial self-fused supramolecular polymer hydrogel for infected wound healing

“…The bisamide structure organized the second crosslinking network, by which the hydrogel was endowed with selfhealing property (figure 1(C)) [23][24][25][26][27][28]. When hydrogels load active substances, they can be endowed with more functions [29][30][31][32][33][34]. Hence we here doped Polymyxin E into the hydrogel.…”