Authors:

Kwiatkoski M, Guimarães FS, Del-Bel E.

Abstract:

Cannabidiol (CBD), a non-psychoactive constituent of cannabis, has been

reported to induce neuroprotective effects in several experimental
models of brain injury. We aimed at investigating whether this drug
could also improve locomotor recovery of rats submitted to spinal cord
cryoinjury. Rats were distributed into five experimental groups. Animals
were submitted to laminectomy in vertebral segment T10 followed or not
by application of liquid nitrogen for 5 s into the spinal cord at the
same level to cause cryoinjury. The animals received injections of
vehicle or CBD (20 mg/kg) immediately before, 3 h after and daily for
6 days after surgery. The Basso, Beattie, and Bresnahan motor evaluation
test was used to assess motor function post-lesion one day before
surgery and on the first, third, and seventh postoperative days. The
extent of injury was evaluated by hematoxylin-eosin histology and FosB
expression. Cryogenic lesion of the spinal cord resulted in a
significant motor deficit. Cannabidiol-treated rats exhibited a higher
Basso, Beattie, and Bresnahan locomotor score at the end of the first
week after spinal cord injury: lesion + vehicle, day 1: zero, day 7:
four, and lesion + Cannabidiol 20 mg/kg, day 1: zero, day 7: seven.
Moreover, at this moment there was a significant reduction in the extent
of tissue injury and FosB expression in the ventral horn of the spinal
cord. The present study confirmed that application of liquid nitrogen to
the spinal cord induces reproducible and quantifiable spinal cord
injury associated with locomotor function impairments. Cannabidiol
improved locomotor functional recovery and reduced injury extent,
suggesting that it could be useful in the treatment of spinal cord
lesions.