title: Tetramethylpyrazine induces SH-SY5Y cell differentiation toward the neuronal phenotype through activation of the PI3K/Akt/Sp1/TopoIIβ pathway.
abstract: Tetramethylpyrazine (TMP) is an active compound extracted from the traditional Chinese medicinal herb Chuanxiong. Previously, we have shown that TMP induces human SH-SY5Y neuroblastoma cell differentiation toward the neuronal phenotype by targeting topoisomeraseIIβ (TopoIIβ), a protein implicated in neural development. In the present study, we aimed to elucidate whether the transcriptional factors specificity protein 1 (Sp1) and nuclear factor Y (NF-Y), in addition to the upstream signaling pathways ERK1/2 and PI3K/Akt, are involved in modulating TopoIIβ expression in the neuronal differentiation process. We demonstrated that SH-SY5Y cells treated with TMP (80μM) terminally differentiated into neurons, characterized by increased neuronal markers, tubulin βIII and microtubule associated protein 2 (MAP2), and increased neurite outgrowth, with no negative effect on cell survival. TMP also increased the expression of TopoIIβ, which was accompanied by increased expression of Sp1 in the differentiated neuron-like cells, whereas NF-Y protein levels remained unchanged following the differentiation progression. We also found that the phosphorylation level of Akt, but not ERK1/2, was significantly increased as a result of TMP stimulation. Furthermore, as established by chromatin immunoprecipitation (ChIP) assay, activation of the PI3K/Akt pathway increased Sp1 binding to the promoter of the TopoIIβ gene. Blockage of PI3K/Akt was shown to lead to subsequent inhibition of TopoIIβ expression and neuronal differentiation. Collectively, the results indicate that the PI3K/Akt/Sp1/TopoIIβ signaling pathway is necessary for TMP-induced neuronal differentiation. Our findings offer mechanistic insights into understanding the upstream regulation of TopoIIβ in neuronal differentiation, and suggest potential applications of TMP both in neuroscience research and clinical practice to treat relevant diseases of the nervous system.
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Yong-Xin
authors.initials: YX
authors.lastname: Yan
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Jun-Xia
authors.initials: JX
authors.lastname: Zhao
authors.affiliation: Department of Human Anatomy, Hebei Medical University, Hebei, PR China.
authors.forename: Shuo
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Na-Jing
authors.initials: NJ
authors.lastname: Zhou
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Jia
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Sheng-Jie
authors.initials: SJ
authors.lastname: Yao
authors.affiliation: Department of Human Anatomy, Hebei Medical University, Hebei, PR China.
authors.forename: Cui-Li
authors.initials: CL
authors.lastname: Cao
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Yan-Ling
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Yan-Nan
authors.initials: YN
authors.lastname: Xu
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Department of Cell Biology, Hebei Medical University, Hebei, PR China. Electronic address: yanyunli2015@163.com.
authors.forename: Yun-Li
authors.initials: YL
authors.lastname: Yan
authors.affiliation: Department of Human Anatomy, Hebei Medical University, Hebei, PR China; Hebei Key Laboratory for Brain Aging and Cognitive Neuroscience, Hebei, PR China.
authors.forename: Hui-Xian
authors.initials: HX
authors.lastname: Cui
mesh_terms: D023081:CCAAT-Binding Factor / Q000378:metabolism; D045744:Cell Line, Tumor; D054338:Cell Transdifferentiation; D004250:DNA Topoisomerases, Type II / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004353:Drug Evaluation, Preclinical; D059585:G1 Phase Cell Cycle Checkpoints; D015870:Gene Expression; D006801:Humans; D009474:Neurons / Q000201:enzymology*; D010641:Phenotype; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011719:Pyrazines / Q000494:pharmacology*; D015398:Signal Transduction; D016329:Sp1 Transcription Factor / Q000378:metabolism; D015533:Transcriptional Activation
chemical_list: D023081:CCAAT-Binding Factor; D004268:DNA-Binding Proteins; D011719:Pyrazines; D016329:Sp1 Transcription Factor; C108209:SP1 protein, human; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D004250:DNA Topoisomerases, Type II; C017953:tetramethylpyrazine
keywords: Neuronal differentiation; PI3K/Akt; SH-SY5Y cell; Specificity protein 1; Tetramethylpyrazine; TopoisomeraseIIβ