Motor and sensitive recovery after injection of a physically cross-linked PNIPAAm-g-PEG hydrogel in rat hemisectioned spinal cord

Publication date: Available online 23 October 2019Source: Materials Science and Engineering: CAuthor(s): Maxime Bonnet, Thomas Trimaille, Brezun Jean-Michel, François Feron, Didier Gigmes, Tanguy Marqueste, Patrick DecherchiAbstractIn line with experiments showing that implanted hydrogels are promising tools, we designed and injected, after a C2 spinal cord hemisection, a thermoresponsive and thermoreversible physically cross-linked poly(N-isopropylacrylamide)-poly(ethylene glycol) copolymer in order to reduce functional deficits and provide a favorable environment to axotomized axons.Nasal olfactory ecto-mesenchymal stem cells were cultured on the hydrogel in order to verify its biocompatibility. Then, inflammatory reaction (Interleukin-1β and 6, Tumor Necrosis Factor-α) was examined 15 days post-hydrogel injection. Functional recovery (postural and locomotor activities, muscle strength and tactile sensitivity) was assessed once a week, during 12 weeks. Finally, at 12 weeks post-injection, spinal reflexivity and ventilatory adjustments were measured, and the presence of glial cells and regenerated axons were determined in the injured area.Our results indicate that cells survived and proliferated on the hydrogel which, itself, did not induce an enhanced inflammation. Furthermore, we observed significant motor and sensitive improvements in hydrogel-injected animals. Hydrogel also induced H-reflex recovery close to control animals but no improved ventilatory adjustment to el...
Source: Materials Science and Engineering: C - Category: Materials Science Source Type: research