Acute traumatic
spinal cord injury (SCI) is marked by the enhanced production of local
cytokines and pro-inflammatory substances that induce
gliosis and prevent reinnervation. The
transplantation of stem cells is a promising treatment strategy for SCI. In order to facilitate functional recovery, we employed stem cell
therapy alone or in combination with
curcumin, a naturally-occurring anti-inflammatory component of turmeric (Curcuma longa), which potently inhibits NF-κB.
Spinal cord contusion following
laminectomy (T9-10) was performed using a weight drop apparatus (10 g over a 12.5 or 25 mm distance, representing moderate or severe SCI, respectively) in Sprague-Dawley rats. Neural stem cells (NSC) were isolated from subventricular zone (SVZ) and transplanted at the site of injury with or without
curcumin treatment. Functional recovery was assessed by BBB score and
body weight gain measured up to 6 weeks following SCI. At the conclusion of the study, the mass of soleus muscle was correlated with BBB score and
body weight. Stem cell
therapy improved recovery from moderate SCI, however, it had a limited effect on recovery after severe SCI.
Curcumin stimulated NSC proliferation in vitro, and in combination with stem cell
therapy, induced profound recovery from severe SCI as evidenced by improved functional locomotor recovery, increased
body weight, and soleus muscle mass. These findings demonstrate that
curcumin in conjunction with stem cell
therapy synergistically improves recovery from severe SCI. Furthermore, our results indicate that the effect of
curcumin extends beyond its known anti-inflammatory properties to the regulation of stem cell proliferation.