CaMKII-Mediated CREB Phosphorylation Is Involved in Ca2+-Induced BDNF mRNA Transcription and Neurite Outgrowth Promoted by Electrical Stimulation

Xiaodong Yan; Juanfang Liu; Zhengxu Ye; Jinghui Huang; Fei He; Wei Xiao; Xueyu Hu; Zhuojing Luo

doi:10.1371/journal.pone.0162784

CaMKII-Mediated CREB Phosphorylation Is Involved in Ca2+-Induced BDNF mRNA Transcription and Neurite Outgrowth Promoted by Electrical Stimulation

PLoS One. 2016 Sep 9;11(9):e0162784. doi: 10.1371/journal.pone.0162784. eCollection 2016.

Authors

Xiaodong Yan^{1

2}, Juanfang Liu³, Zhengxu Ye¹, Jinghui Huang¹, Fei He⁴, Wei Xiao¹, Xueyu Hu¹, Zhuojing Luo¹

Affiliations

¹ Department of Orthopaedics, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, China.
² Department of Orthopaedics, Tangdu Hospital, Fourth Military Medical University, Xi'an 710038, China.
³ Department of Clinical Aerospace Medicine, Fourth Military Medical University, Xi'an 710032, China.
⁴ Department of Hereditary and Development, Basic Unit, Fourth Military Medical University, Xi'an 710032, China.

Abstract

Electrical stimulation (ES)-triggered up-regulation of brain-derived neurotrophic factor (BDNF) and neurite outgrowth in cultured rat postnatal dorsal root ganglion neurons (DRGNs) is calcium (Ca2+)-dependent. The effects of increased Ca2+ on BDNF up-regulation and neurite outgrowth remain unclear. We showed here that ES increased phosphorylation of the cAMP-response element binding protein (CREB). Blockade of Ca2+ suppressed CREB phosphorylation and neurite outgrowth. Down-regulation of phosphorylated (p)-CREB reduced BDNF transcription and neurite outgrowth triggered by ES. Furthermore, blockade of calmodulin-dependent protein kinase II (CaMKII) using the inhibitors KN93 or KN62 reduced p-CREB, and specific knockdown of the CaMKIIα or CaMKIIβ subunit was sufficient to suppress p-CREB. Recombinant BDNF or hyperforin reversed the effects of Ca2+ blockade and CaMKII knockdown. Taken together, these data establish a potential signaling pathway of Ca2+-CaMKII-CREB in neuronal activation. To our knowledge, this is the first report of the mechanisms of Ca2+-dependent BDNF transcription and neurite outgrowth triggered by ES. These findings might help further investigation of complex molecular signaling networks in ES-triggered nerve regeneration in vivo.

MeSH terms

Animals
Brain-Derived Neurotrophic Factor / genetics*
Brain-Derived Neurotrophic Factor / metabolism
Calcium / pharmacology*
Calcium-Calmodulin-Dependent Protein Kinase Kinase / metabolism
Calcium-Calmodulin-Dependent Protein Kinase Type 2 / metabolism*
Cyclic AMP Response Element-Binding Protein / metabolism*
Electric Stimulation
Ganglia, Spinal / drug effects
Ganglia, Spinal / metabolism
Intracellular Space / metabolism
Models, Biological
Neuronal Outgrowth / drug effects*
Neuronal Outgrowth / genetics
Neurons / drug effects
Neurons / metabolism
Phosphorylation / drug effects
Protein Subunits / metabolism
RNA, Messenger / genetics
RNA, Messenger / metabolism
Rats, Sprague-Dawley
Reproducibility of Results
Transcription, Genetic / drug effects*

Substances

Brain-Derived Neurotrophic Factor
Cyclic AMP Response Element-Binding Protein
Protein Subunits
RNA, Messenger
Calcium-Calmodulin-Dependent Protein Kinase Kinase
Calcium-Calmodulin-Dependent Protein Kinase Type 2
Calcium

Grants and funding

This work was supported by the National Natural Science Foundation of China (No. 30770571, 81401001 and 81101352, ZL) and Elite Talent Cultivation Programme of Tangdu hospital (No. 20125087, XH). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.