Overexpression of neuronal calcium sensor-1 to promote axonal regeneration

Patients with spinal cord injury (SCI) are often left with severe sensory, motor and autonomic functional deficits. In the proposed research we aim to test the hypothesis that adding a calcium sensor protein; neuronal calcium sensor-1 (NCS-1) can enable adult nerves to regenerate. This small molecule is involved in the growth of axons and formation of synapses (the wiring and communication points of nerves) in the embryonic brain and spinal cord. This molecule is usually only expressed in the embryonic nervous system which, as well as normal growth, is also capable of significant regeneration after injury. We plan to increase the NCS-1 content of injured nerves in two models of SCI in the adult rat. The differences between the two models will allow us to examine the contribution of different mechanisms that may underlie any functional recovery caused by the increase in NCS-1.
Clinically the treatment of the neuronal injury following SCI is delayed by the need to stabilise the patient, therefore we will test if increasing NCS-1 after as opposed to at the same time as the injury can induce recovery. We hope this work may contribute to new treatment options in SCI.

We will test the hypothesis that Neuronal Calcium Sensor-1 (NCS-1, frequenin) promotes regeneration of adult neurones and may be of use in treating spinal cord injury.
We identified NCS-1 in a microarray screen of spinal cord treated with a pro-regenerative factor. Published work has demonstrated that NCS-1 can induce axonogenesis, synaptogenesis and plasticity in the developing CNS. To date it has not been associated with axonal growth and regeneration in the adult. We aim to overexpress NCS-1 in neurones using a viral vector and assess growth in vitro and in vivo.
First, we will study adult primary sensory neurones in dissociated cultures and ask if NCS-1 overexpression induces neuritogenesis and neurite outgrowth on permissive and inhibitory substrates. We have pilot data that this is the case. Second, we will study in vivo whether virally overexpressing NCS-1 in the pyramidal neurones of adult rats can promote recovery. Subsequently we will investigate whether this recovery is due to axonal regeneration and/or structural plasticity of unlesioned axons. The work would be carried out in two models of spinal cord injury. Bilateral injury to both descending corticospinal tract (CST) ?dorsal column crush? or unilateral injury to one descending CST ?pyramidotomy?. The former would examine axonal regeneration and the latter structural plasticity. Clinically the treatment of SCI must follow injury. Therefore we will test if delayed overexpression of NCS-1 post-lesion could encourage functional recovery.