Stromal cell-derived factor-1 alpha (SDF-1α) improves neural recovery after spinal cord contusion in rats.

Stromal cell-derived factor-1 alpha (SDF-1α) is an important cytokine, implicated in the control of stem cell trafficking and bone marrow-derived stem cell mobilization. Generally, SDF-1α regulates multiple physiological processes such as embryonic development and organ homeostasis. There is also good evidence that SDF-1α and its receptor CXCR4(1) are key regulators of neurorepair processes after brain ischemia and spinal cord injury. In this study, we investigated the influence of chronic intrathecal delivery of SDF-1α after spinal cord contusion. After contusion T9, male Wistar rats at the age of 12 weeks were intrathecally treated with SDF-1α in different doses (100, 500 and 1000 ng/ml) via an osmotic pump for 28 days. Thereafter, animals were subjected to an open field locomotor test. Behavioral scores were significantly higher in SDF-1α treated animals compared to placebo-treated groups. In addition, we evaluated histopathological changes in the spinal cord in the presence or absence of SDF-1α. Chronic delivery of SDF-1α decreased numbers of apoptotic cells, boosted astroglia and microglia response, induced angiogenesis, and potentiated the number of proliferating cells in a dose-dependent manner. These results clearly indicate an improved functional CNS long-term recovery after spinal cord injury. This behavioral restoration was paralleled by a reduction of apoptosis and changes in neuroinflammatory cells.