Hypoxia promotes apoptosis of neuronal cells through hypoxia-inducible factor-1α-microRNA-204-B-cell lymphoma-2 pathway.
Neuronal cells are highly sensitive to hypoxia and may be subjected to apoptosis when exposed to hypoxia. Several apoptosis-related genes and miRNAs involve in hypoxia-induced apoptosis. This study aimed to examine the role of HIF1α-miR-204-BCL-2 pathway in hypoxia-induced apoptosis in neuronal cells. Annexin V/propidium iodide assay was performed to analyze cell apoptosis in AGE1.HN and PC12 cells under hypoxic or normoxic conditions. The expression of BCL-2 and miR-204 were determined by Western blot and qRT-PCR. The effects of miR-204 overexpression or knockdown on the expression of BCL-2 were evaluated by luciferase assay and Western blot under hypoxic or normoxic conditions. HIF-1α inhibitor YC-1 and siHIF-1α were employed to determine the effect of HIF-1α on the up-regulation of miR-204 and down-regulation of BCL-2 induced by hypoxia. Apoptosis assay showed the presence of apoptosis induced by hypoxia in neuronal cells. Moreover, we found that hypoxia significantly down-regulated the expression of BCL-2, and increased the mRNA level of miR-204 in neuronal cells than that in control. Bioinformatic analysis and luciferase reporter assay demonstrated that miR-204 directly targeted and regulated the expression of BCL-2. Specifically, the expression of BCL-2 was inhibited by miR-204 mimic and enhanced by miR-204 inhibitor. Furthermore, we detected that hypoxia induced cell apoptosis via HIF-1α/miR-204/BCL-2 in neuronal cells. This study demonstrated that HIF-1α-miR-204-BCL-2 pathway contributed to apoptosis of neuronal cells induced by hypoxia, which could potentially be exploited to prevent spinal cord ischemia-reperfusion injury.
Department of Spinal Surgery, The Second Hospital of Shandong University, Ji'nan 250033, China.
Xiuwen
X
Wang
Department of Spinal Surgery, The Second Hospital of Shandong University, Ji'nan 250033, China.
Ji
J
Li
Department of Spinal Surgery, The Second Hospital of Shandong University, Ji'nan 250033, China.
Dongjin
D
Wu
Department of Spinal Surgery, The 7th People's Hospital of Ji'nan, Ji'nan 251400, China.
Xiangpeng
X
Bu
Department of Spinal Surgery, The Second Hospital of Shandong University, Ji'nan 250033, China yongq156@163.com.
Yong
Y
Qiao
D000328:Adult; D000368:Aged; D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002460:Cell Line; D020869:Gene Expression Profiling; D006801:Humans; D000860:Hypoxia; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism*; D035683:MicroRNAs / Q000378:metabolism*; D008875:Middle Aged; D009474:Neurons / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D051381:Rats; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction
D051795:Hypoxia-Inducible Factor 1, alpha Subunit; C549404:MIRN204 microRNA, human; D035683:MicroRNAs; D019253:Proto-Oncogene Proteins c-bcl-2
B-cell lymphoma-2; Spinal cord ischemia–reperfusion injury; hypoxia; hypoxia-inducible factor-1α; microRNA-204; neuronal cells