Cellular and Molecular Neurobiology

, Volume 37, Issue 3, pp 487–498 | Cite as

Expression of Sam68 Associates with Neuronal Apoptosis and Reactive Astrocytes After Spinal Cord Injury

  • Xinlei Chen
  • Lei Liu
  • Rong Qian
  • Jie Liu
  • Yu Yao
  • Zhenhuan Jiang
  • Xinjian Song
  • Jianbing Ren
  • Feng Zhang
Original Research
First Online:
Received:
Accepted:

Abstract

Src-associated in mitosis (Sam68; 68 kDa) is a novel RNA-binding protein that belongs to the signal transduction and activation of RNA family involved in various biological processes. However, the expression and roles of Sam68 in the central nervous system remain unknown. In the present study, we performed a spinal cord injury (SCI) model in adult rats and found a significant increase of Sam68 protein levels in this model, which reached a peak at day 3 and then gradually returned to normal levels at day 14 after SCI. We use immunohistochemistry analysis revealing a widespread distribution of Sam68 in the spinal cord. In addition, double-immunofluorescence staining showed that Sam68 immunoreactivity was found predominantly in neurons and astrocytes. Moreover, colocalization of Sam68/active caspase-3 has been respectively detected in neuronal nuclei, and colocalization of Sam68/PCNA has been detected in glial fibrillary acidic protein. In vitro, we found that depletion of Sam68 by short interfering RNA inhibits neuronal apoptosis and astrocyte proliferation and decreases cyclin D1 protein levels. In conclusion, this is the first study to find the Sam68 expression in SCI. Our results suggest that Sam68 might be illustrated in the apoptosis of neurons and proliferation of astrocytes after SCI. This research will provide new drug targets for clinical treatment of SCI.

Keywords

Spinal cord injury Sam68 Neuronal apoptosis Proliferation Cell cycle Rat 

Abbreviations

Sam68

Src-associated in mitosis

SCI

Spinal cord injury

NeuN

Neuronal nuclear antigen

PCNA

Proliferating cell nuclear antigen

GFAP

Glial fibrillary acidic protein

GAPDH

Glyceraldehyde-3-phosphate dehydrogenase

siRNA

Short interfering RNA

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Notes

Acknowledgments

This work was supported by National Natural Science Foundation of China (Grant No. 81402220) and Nantong University Innovation Project (YKS14011).

Supplementary material

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Supplementary material 1 (TIFF 416 kb)
10571_2016_384_MOESM2_ESM.tif (2.8 mb)
Supplementary material 2 (TIFF 2820 kb)

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  • Xinlei Chen
    • 1
  • Lei Liu
    • 2
  • Rong Qian
    • 1
  • Jie Liu
    • 1
  • Yu Yao
    • 1
  • Zhenhuan Jiang
    • 2
  • Xinjian Song
    • 3
  • Jianbing Ren
    • 3
  • Feng Zhang
    • 1
  1. 1.Department of Orthopaedics, Affiliated Hospital of Nantong University, Jiangsu Province Key Laboratory for Information and Molecular Drug TargetNantong UniversityNantongChina
  2. 2.Department of OrthopaedicsPeople’s Hospital of Yixing CityYixingChina
  3. 3.Department of RehabilitationNantong Second People’s HospitalNantongChina

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