Targeted retrograde transfection of adenovirus vector carrying brain-derived neurotrophic factor gene prevents loss of mouse (twy/twy) anterior horn neurons in vivo sustaining mechanical compression.
METHODS
Immunohistochemical analysis after adenovirus (AdV)-mediated BDNF gene transfer in and around the area of mechanical compression in the cervical spinal cord of the hyperostotic mouse (twy/twy).


OBJECTIVE
To investigate the neuroprotective effect of targeted AdV-BDNF gene transfection in the twy mouse with spontaneous chronic compression of the spinal cord motoneurons.


BACKGROUND
Several studies reported the neuroprotective effects of neurotrophins on injured spinal cord. However, no report has described the effect of targeted retrograde neurotrophic gene delivery on motoneuron survival in chronic compression lesions of the cervical spinal cord resembling lesions of myelopathy.


METHODS
LacZ marker gene using adenoviral vector (AdV-LacZ) was used to evaluate retrograde delivery from the sternomastoid muscle in adult twy mice (16-week-old) and (control). Four weeks after the AdV-LacZ or AdV-BDNF injection, the compressed cervical spinal cord was removed en bloc for immunohistologic investigation of b-galactosidase activity and immunoreactivity and immunoblot analyses of BDNF. The number of anterior horn neurons was counted using Nissl, ChAT and AChE staining.


RESULTS
Spinal accessory motoneurons between C1 and C3 segments were successfully transfected by AdV-LacZ in both twy and ICR mice after targeted intramuscular injection. Immunoreactivity to BDNF was significantly stronger in AdV-BDNF-gene transfected twy mice than in AdV-LacZ-gene transfected mice. At the cord level showing the maximum compression in AdV-BDNF-transfected twy mice, the number of anterior horn neurons was sinificantly higher in the topographic neuronal cell counting of Nissl-, ChAT-, and AChE-stained samples than in AdV-LacZ-injected twy mice.


CONCLUSIONS
Targeted AdV-BDNF-gene delivery significantly increased Nissl-stained anterior horn neurons and enhanced cholinergic enzyme activities in the twy. Our results suggest that targeted retrograde AdV-BDNF-gene in vivo delivery may enhance neuronal survival even under chronic mechanical compression.
Xu
Kan
K
Division of Orthopaedics and Rehabilitation Medicine, Department of Surgery, University of Fukui Faculty of Medicine, Matsuoka, Fukui, Japan.
Uchida
Kenzo
K
Nakajima
Hideaki
H
Kobayashi
Shigeru
S
Baba
Hisatoshi
H
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000870:Anterior Horn Cells / Q000378:metabolism / Q000473:pathology*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics* / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005240:Feasibility Studies; D005822:Genetic Vectors; D015576:Hyperostosis / Q000150:complications / Q000235:genetics / Q000378:metabolism*; D015151:Immunoblotting; D051379:Mice; D008817:Mice, Mutant Strains; D013116:Spinal Cord / Q000378:metabolism; D013117:Spinal Cord Compression / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D013122:Spinal Diseases / Q000150:complications / Q000235:genetics / Q000378:metabolism*; D013194:Staining and Labeling; D014162:Transfection; D001616:beta-Galactosidase / Q000378:metabolism
D019208:Brain-Derived Neurotrophic Factor; D002795:Choline O-Acetyltransferase; D001616:beta-Galactosidase