Neuroprotective effect of brain-derived neurotrophic factor mediated by autophagy through the PI3K/Akt/mTOR pathway

Chen,Ai; Xiong,Li-Jing; Tong,Yu; Mao,Meng

doi:10.3892/mmr.2013.1628

Neuroprotective effect of brain-derived neurotrophic factor mediated by autophagy through the PI3K/Akt/mTOR pathway

Authors:
- Ai Chen
- Li-Jing Xiong
- Yu Tong
- Meng Mao
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Affiliations: Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China, Laboratory of Early Developmental and Injuries, West China Institute of Woman and Children's Health, West China Second University Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
Published online on: August 13, 2013 https://doi.org/10.3892/mmr.2013.1628
Pages: 1011-1016

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Abstract

Brain‑derived neurotrophic factor (BDNF) has been demonstrated to be a potent growth factor that is beneficial in neuronal functions following hypoxia‑ischemia (HI). Mature BDNF triggers three enzymes, mitogen‑activated protein kinase (MAPK), phosphatidylinositol 3‑kinase (PI3K) and phosphoinositide phospholipase C-γ (PLCγ), which are its predominant downstream regulators. The PI3K‑Akt signaling pathway is upstream of the mammalian target of rapamycin (mTOR), which is important in the induction of autophagy. However, whether the neuroprotective effect of BDNF is mediated by autophagy through the PI3K/Akt/mTOR pathway remains to be elucidated. Cortical neurons were cultured following isolation from pregnant rats (gestational days 16‑18). The induction of autophagy following BDNF treatment was analyzed by microtubule‑associated protein light chain 3 (LC3) conversion and autophagosome formation. The phosphorylation of Akt, mTOR and ribosomal protein S6 kinase (p70S6K) was analyzed in cultured cells with or without BDNF treatment. Cell viability was determined by a Cell Counting Kit‑8 for estimating the protective effect of BDNF. Results demonstrated that autophagy was induced in cells with oxygen deprivation. BDNF promoted cell viability via the upregulation of autophagy. Moreover, LC3 upregulation was related to Akt/mTOR/p70S6K inhibition by BDNF. In conclusion, the results suggested that the neuroprotective effect of BDNF was mediated by autophagy through the PI3K/Akt/mTOR pathway.

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