Overexpression of the X-Linked Inhibitor of Apoptosis Protein (XIAP) in Neurons Improves Cell Survival and the Functional Outcome after Traumatic Spinal Cord Injury

Traumatic spinal cord injury (SCI) leads to neuron death and loss of function. This study investigates whether increasing the levels of a protein called X-linked inhibitor of apoptosis protein (XIAP) in neurons can protect them and improve recovery after SCI. The researchers used transgenic mice that overexpress XIAP in their neurons and a human cell line modified to overexpress XIAP. They found that increasing XIAP levels led to better neuron survival, tissue preservation, and motor recovery after SCI in mice. In the cell line, overexpression of XIAP reduced caspase activity (enzymes that promote cell death) and apoptotic cell death after exposure to harmful stimuli, suggesting that XIAP's protective effects are related to its ability to inhibit programmed cell death.

• 1
  Overexpression of hXIAP in neurons of transgenic mice (CB57hXIAP+) led to a significant increase in the number of surviving neurons after SCI, particularly in the penumbra regions around the injury epicenter.
• 2
  CB57hXIAP+ mice exhibited greater white matter preservation, especially in the caudal sections close to the injury site, indicating reduced tissue damage due to hXIAP overexpression.
• 3
  CB57hXIAP+ mice showed improved locomotor recovery compared to wild-type mice, with higher BMS scores and a greater capacity for coordinated walking, suggesting that hXIAP overexpression reduces motor skill deficits.