CAQK modification enhances the targeted accumulation of metformin-loaded nanoparticles in rats with spinal cord injury.

Spinal cord injury (SCI) often causes neuronal membrane rupture and immediate death of neurons, followed by complicated secondary injuries. Treatment of SCI still remains a major challenge in clinical practice; thus, a great advance is urgently needed in this field. Metformin (MET) has anti-oxidant, anti-inflammatory, anti-apoptotic and neuroprotective properties, which may exert a potential therapeutic effect on SCI. In this study, we established a zein-based MET-loaded nanodrug system (CAQK-MET-NPs) for the targeted drug delivery for SCI. The results showed that MET could be effectively encapsulated into zein to obtain the zein-based spherical nanoparticles. Pharmacokinetic analysis indicated that CAQK-MET-NPs exhibited sustained-release and long-term therapeutic effects. The fluorescence imaging and tissue distribution experiments showed that CAQK-MET-NPs could efficiently accumulate at the lesion site of SCI rats. In conclusion, CAQK-MET-NPs may be a promising nanodrug for the treatment of SCI.