title: Concomitant activation of the PI3K/Akt and ERK1/2 signalling is involved in cyclic compressive force-induced IL-6 secretion in MLO-Y4 cells.
abstract: IL-6 has a dual role in bone remodelling. The ERK1/2 pathway partially upregulated IL-6 secretion in osteocyte-like MLO-Y4 cells exposed to CCF. We have now investigated the possible role of phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway in the CCF-induced IL-6 expression. MLO-Y4 cells were treated with CCF 2,000 µstrain, 2 Hz, or 10, 30 min, 1, 3 and 6 h. IL-6 expression, Akt and ERK1/2 and PI3K/Akt phosphorylation were determined by RT-PCR, ELISA and Western blotting. Inhibition of PI3K/Akt with LY294002 or ERK1/2 with PD98059 significantly attenuated IL-6 upregulation, and IL-6 expression was abolished by inhibiting both pathways. Inhibition of one pathway downregulated the other's phosphorylation level. In conclusion, concomitant activation of PI3K/Akt and ERK1/2 pathways mediated IL-6 expression in MLO-Y4 cells under CCF.
authors.affiliation: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China; Department of Prosthodontics, West China College of Stomatology, Sichuan University, Chengdu, 610041, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yin
authors.forename: Zhichao
authors.initials: Z
authors.lastname: Hao
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Ma
authors.forename: Shuang
authors.initials: S
authors.lastname: Liao
authors.forename: Xianxian
authors.initials: X
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Fu
authors.forename: Yeke
authors.initials: Y
authors.lastname: Wu
authors.forename: Jiefei
authors.initials: J
authors.lastname: Shen
authors.forename: Ping
authors.initials: P
authors.lastname: Zhang
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Li
authors.forename: Hang
authors.initials: H
authors.lastname: Wang
mesh_terms: D000818:Animals; D002460:Cell Line; D019245:Compressive Strength / Q000502:physiology*; D004789:Enzyme Activation / Q000502:physiology; D015850:Interleukin-6 / Q000378:metabolism*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D010011:Osteocytes / Q000378:metabolism*; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D013314:Stress, Mechanical
chemical_list: D015850:Interleukin-6; D058539:Phosphatidylinositol 3-Kinase; D051057:Proto-Oncogene Proteins c-akt
keywords: ERK1/2; PI3K/Akt; compressive force; interleukin-6; osteocyte