The oligodendrocyte lineage genes Olig1 and Olig2 in CNS development

After contusion-derived spinal cord injury there is localized tissue disruption and energy failure that results in early necrosis and delayed apoptosis, events that contribute to chronic central pain in a majority of patients. We assessed mechanisms of contusion-induced apoptosis of neurons and glia in a known central pain signalling pathway, the spinothalamic tract (STT), which may be a contributor to SCI-induced pain. Twenty-four hours after injury there was demonstrable apoptosis among neurons of the spinothalamic tract. Apoptosis in the injured spinal cord correlated well with prompt decreases in Bcl-xL and Bcl-xL/Bax protein ratios at the contusion site. There was definitive triggering of the inflammatory cytokine cascade with IL-1b being most robust and prompt in responding. Clearly, a better understanding of inflammatory processes, especially the role of cytokines after nerve injury, can lead to the development of new therapies that may prevent, and not just treat chronic central pain. Intervention in the inflammatory cascade had beneficial effects with confounds, which were mostly assessed by cDNA microarray analyses. We interpret these results as evidence that regulation of Bcl-xL and other genes that determine cell death outcomes may play a role in the inflammatory response to spinal injury and pain signalling function.
Acknowledgements:   Supported in part by NINDS and Mission Connect.