Targeted-delivery of nanomedicine-enabled methylprednisolone to injured spinal cord promotes neuroprotection and functional recovery after acute spinal cord injury in rats

To date, no therapy has been proven to be efficacious in fully restoring neurological functions after spinal cord injury (SCI). Systemic high-dose methylprednisolone (MP) improves neurological recovery after acute SCI in both animal and human. MP therapy remains controversial due to its modest effect on functional recovery and significant adverse effects. To overcome the limitation of MP therapy, we have developed a N-(2-hydroxypropyl) methacrylamide copolymer-based MP prodrug nanomedicine (Nano-MP) that can selectively deliver MP to the SCI lesion when administered systemically in a rat model of acute SCI. Our in vivo data reveal that Nano-MP is significantly more effective than free MP in attenuating secondary injuries and neuronal apoptosis. Nano-MP is superior to free MP in improving functional recovery after acute SCI in rats. These data support Nano-MP as a promising neurotherapeutic candidate, which may provide potent neuroprotection and accelerate functional recovery with improved safety for patients with acute SCI.