Loss of microRNA-124 expression in neurons in the peri-lesion area in mice with spinal cord injury.
MicroRNA-124 (miR-124) is abundantly expressed in neurons in the mammalian central nervous system, and plays critical roles in the regulation of gene expression during embryonic neurogenesis and postnatal neural differentiation. However, the expression profile of miR-124 after spinal cord injury and the underlying regulatory mechanisms are not well understood. In the present study, we examined the expression of miR-124 in mouse brain and spinal cord after spinal cord injury using in situ hybridization. Furthermore, the expression of miR-124 was examined with quantitative RT-PCR at 1, 3 and 7 days after spinal cord injury. The miR-124 expression in neurons at the site of injury was evaluated by in situ hybridization combined with NeuN immunohistochemical staining. The miR-124 was mainly expressed in neurons throughout the brain and spinal cord. The expression of miR-124 in neurons significantly decreased within 7 days after spinal cord injury. Some of the neurons in the peri-lesion area were NeuN(+)/miR-124(-). Moreover, the neurons distal to the peri-lesion site were NeuN(+)/miR-124(+). These findings indicate that miR-124 expression in neurons is reduced after spinal cord injury, and may reflect the severity of spinal cord injury.
Department of Anatomy, Hebei North University, Zhangjiakou, Hebei Province, China.
Yu
Y
Zhao
Department of Anatomy, Hebei North University, Zhangjiakou, Hebei Province, China.
Hui
H
Zhang
Department of Stomatology, the First Hospital of Zhangjiakou, Zhangjiakou, Hebei Province, China.
Dan
D
Zhang
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Cai-Yong
CY
Yu
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Xiang-Hui
XH
Zhao
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Fang-Fang
FF
Liu
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Gan-Lan
GL
Bian
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Gong
G
Ju
Institute of Neurosciences, the Fourth Military Medical University, Xi'an, Shaanxi Province, China.
Jian
J
Wang
NSFC grants; NeuN protein; apoptosis; brain; digoxin; immunohistochemistry; in situ hybridization; microRNA; nerve regeneration; neural plasticity; neural regeneration; repair; spinal cord; spinal cord injury