Fibrin scaffolds embedded with sonic hedgehog/chitosan microspheres for recovery of spinal cord injury in rats

Abstract

Sonic hedgehog (SHH) has been shown to exert a protection on promoting the spinal cord injury (SCI) recovery, but it can’t remain with its biological activity and sustained release at the injury site for long-term application. Herein, fibrin scaffolds embedded with SHH-loaded chitosan (CS) microspheres (SHH/CS) were synthesized and applied to provide protection and regeneration for complete transected spinal cord in rats. Characteristics of fibrin scaffolds embedded with SHH/CS microspheres, histological studies, immunohistochemistry staining, Western Blotting and recovery of motor function were conducted after implantation, respectively. Result showed that SHH maintained its biological activity and continued to act at the injury site, and the fibrin scaffolds embedded with SHH/CS microspheres could protect neurons and reduce apoptosis in the in vivo study, it also promoted some nerve fibers cross the spinal cord injury area. Moreover, the scaffolds improved partial motor function of double-hindlimb on a macro level. Overall, the fibrin scaffolds embedded with SHH/CS microspheres showed more satisfactory effect on nerve regeneration, tissue cavities prevention and motor function improvement, compared to fibrin scaffolds with SHH directly encapsulated into or fibrin scaffolds alone.

An injectable self-adaptive polymer as a drug carrier for the treatment of nontraumatic early-stage osteonecrosis of the femoral head

“…Furthermore, the moderate rate of solidification enables surgeons to conduct injections at a more leisurely pace. Compared to hydrogels, 56 microspheres, 57 , 58 or soft scaffolds, 59 GPCL also exhibited excellent mechanical properties and acted as hard tissue. The mechanical properties of GPCL were found to be similar to those of cancellous bone, and GPCL is capable of acting as a scaffold, 60 providing mechanical support in the tunnel.…”

Progress in the application of sustained-release drug microspheres in tissue engineering

“…In addition, Yang et al. synthesized SHH-loaded chitosan microspheres (SHH/CS) embedded in fibrin scaffolds and then applied this treatment for the protection and regeneration of completely transverse spinal cord injuries in rats [ 157 ]. The results showed that SHH was able to maintain its biological activity and continue to act on the site of injury, and SHH/CS microsphere-embedded fibrin scaffolds showed good effects in nerve regeneration, tissue cavity prevention, and motor function improvement, compared with the separately wrapped fibrin scaffolds.…”

From mesenchymal niches to engineered in vitro model systems: Exploring and exploiting biomechanical regulation of vertebrate hedgehog signalling

“…Vesicles-loaded with SAG (a Smo agonist) immobilised on apatite-coated-PLGA scaffolds were shown to induce osteogenic differentiation of BM-MSCs in vitro and enhanced the healing of size-specific bone-defects in vivo by increasing the expression of Gli1 [ 325 ]. Moreover, Shh-loaded chitosan microspheres encapsulated into fibrin scaffolds is another approach that has been used for modulating Hh signalling to restore stem cell proliferation and enhance regeneration in spinal cord injury [ 326 ].…”