Phosphorylated retinoblastoma protein (p-Rb) is involved in neuronal apoptosis after traumatic brain injury in adult rats.
Phosphorylated retinoblastoma protein (p-Rb), a well identified cell cycle related protein, is involved in regulating the biological functions of various cell types including neurons. One attractive biological function of p-Rb is releasing E2F transcription factor to induce S-phase entry and cellular proliferation of mitotic cells. However, some studies point out that the role of p-Rb in post-mitotic cells such as mature neurons is unique; it may induce cellular apoptosis rather than proliferation via regulating cell cycle reactivation. Up to now, the knowledge of p-Rb function in CNS is still limited. To investigate whether p-Rb is involved in CNS injury and repair, we performed a traumatic brain injury model in adult rats. Up-regulation of p-Rb was observed in the injured brain cortex by western blot analysis and immunohistochemistry staining. Terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling (TUNEL) and 4',6-diamidino-2-phenylindole (DAPI) staining suggested that p-Rb was relevant to neuronal apoptosis after brain injury. In addition, glutamate excitotoxic model of primary cortex neurons was introduced to further investigate the role of p-Rb in neuronal apoptosis; the result implied p-Rb was associated with cell cycle activation in the apoptotic neurons. Based on our data, we suggested that p-Rb might play an important role in neuronal apoptosis after traumatic brain injury in rat; which might also provide a basis for the further study on its role in regulating cell cycle re-entry in apoptotic neurons, and might gain a novel strategy for the clinical therapy for traumatic brain injury.
Department of Orthopaedics, Second Affiliated Hospital of Nantong University, Nantong 226002, Jiangsu, People's Republic of China.
Wei
W
Liu
Xiaojuan
X
Liu
Huilin
H
Yang
Xinhui
X
Zhu
Hong
H
Yi
Xuesong
X
Zhu
Jie
J
Zhang
D000818:Animals; D017209:Apoptosis; D015415:Biomarkers; D001930:Brain Injuries / Q000378:metabolism* / Q000503:physiopathology; D002453:Cell Cycle; D002478:Cells, Cultured; D002540:Cerebral Cortex / Q000293:injuries / Q000378:metabolism / Q000503:physiopathology; D004195:Disease Models, Animal; D050687:E2F1 Transcription Factor / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D010766:Phosphorylation; D011485:Protein Binding; D051381:Rats; D016160:Retinoblastoma Protein / Q000378:metabolism*; D015854:Up-Regulation
D015415:Biomarkers; D050687:E2F1 Transcription Factor; C493755:E2f1 protein, rat; D016160:Retinoblastoma Protein