ABSTRACT
Objective To investigate the effect and molecular mechanism of botulinum neurotoxin serotype A (BoNT/A) heavy chain on neuron regeneration. Methods Cell culture, rats, immunofluorescence, SDS-PAGE and western blot, etc. were adopted in this study to explore the alterations of histone-3 acetylation (acetyl-H3 ) by local treatment of BoNT/A heavy chain to spinal cord injury (SCI) in rats (in vivo) or by adding it into cell culture (in vitro). Meanwhile, the relevance of acetyl-H3 to neurite out-growth based on SCI and cell culture with BoNT/A heavy chain application was approached as well. Results The application of BoNT/A heavy chain to cultured Neuro-2a cells increased the level of H3 acetylation. The increase of H3 acetylation was paralleled with the growth of neuritogenesis. Also, the neuronal treatment of BoNT/A heavy chain to SCI promoted the re-growth of neuronal processes surrounding the lesions. The growth of neuronal processes was positively correlated to the level of H3 acetylation. During the periods of BoNT/A heavy chain treatment in vivo or in vitro, the increase of H3 acetylation showed two peaks. Conclusions BoNT/A heavy chain increased the H3 acetylation, which might be one of its neuritogenic mechanisms.