Sensory and Motor Behavior Evidences Supporting the Usefulness of Conditioned Medium from Dental Pulp-Derived Stem Cells in Spinal Cord Injury in Rats

Abstract

Study Design Experimental animal study. Purpose This study aimed to assess effects of conditioned medium (CM) of dental pulp-derived stem cells loaded in collagen hydrogel on functional recovery following spinal cord injury (SCI). Overview of Literature SCI affects sensory and motor functions, and behavioral recovery is the most essential purpose of therapeutic intervention. Recent studies have reported that CM from dental pulp-derived stem cells has therapeutic benefits. In addition, collagen hydrogel acts as a drug delivery system in SCI experiments. Methods Stem cells from human exfoliated deciduous teeth (SHEDs) were cultured, and SHED-CM was harvested and concentrated. Collagen hydrogel containing SHED-CM was prepared. The rats were divided into five groups receiving laminectomy, compressive SCI with or without intraspinal injection of biomaterials (SHED-CM), and collagen hydrogel with or without SHED-CM. Basso, Beattie, and Bresnahan (BBB) scoring, inclined plane, cold allodynia, and beam walk tests were performed for 6 weeks to assess locomotor, motor, sensory, and sensory-motor performances, respectively. Results Scores of the rats receiving SHED-CM loaded in collagen hydrogel were significantly better than those of the other injured groups at 1-week post-injury for BBB, 2 weeks for inclined plane, 2 weeks for cold allodynia, and 4 weeks for beam walk tests (p <0.05). The differences remained significant throughout the study. Conclusions Intraspinal administration of SHED-CM loaded in collagen hydrogel leads to improved functional recovery and proposes a cell-free therapeutic approach for SCI.

Keywords

• Spinal cord injuries
• Collagen
• Conditioned culture media
• Behavior
• Rats