Bone marrow-derived mesenchymal stem cells (BM-MSCs) inhibit apoptosis of spinal cord cells in a kaolin-induced syringomyelia-associated scoliosis rabbit model.

The mechanisms and causes of scoliosis are believed to be multifactorial. Syringomyelia can often be found in scoliosis patients but the relationship between the two remains obscure. In this study, based on a rabbit model of syringomyelia-associated scoliosis, the involved pathological mechanism was explored in an attempt to further understand the relationship. This will also be helpful in determining how scoliosis occurred. In this study, a syringomyelia-associated scoliosis rabbit model was established by kaolin-injection technique. Spinal cell apoptosis following scoliosis and syringomyelia induction were analyzed. Furthermore, the effect of bone marrow-mesenchymal stem cell (BM-MSCs) transplantation on spinal cell apoptosis and on incidence of scoliosis and syringomyelia were assessed. Most of the experimental animals injected with kaolin developed progressive scoliotic curves and syringomyelia. Syrinx and scoliosis were found in 64.7% and 58.8% of the experimental animals. Syringomyelia-associated scoliosis appeared in 41.2% of the animals. Syrinx size and scoliotic curves increased with time. Apoptosis was found on postoperative day 3 both in surgical segments and adjacent segments in the spinal cord, peaking at week 6. The number of apoptotic cells was significantly lower in BM-MSCs transplantation group compared with the saline-injection group. Fewer rabbits in the BM-MSCs injection group developed scoliosis or syringomyelia by the end of the experiment. Our findings indicate the potential value of kaolin-induced scoliotic animal models. For the first time, we studied features of apoptosis of spinal cells in a syringomyelia-associated scoliosis rabbit model. Our results demonstrate that BM-MSCs transplanted into the spinal cord decrease both apoptosis of spinal cells and incidence of scoliosis and syringomyelia.