Circ_016719 plays a critical role in neuron cell apoptosis induced by I/R via targeting miR-29c/Map2k6. (February 2020)

• Record Type: Journal Article
• Authors: Tang, Chaogang; Ou, Jianying; Kou, Li; Deng, Jinfeng; Luo, Shijian
• Is Part Of: Molecular and cellular probes. Volume 49(2020)
• Publication Date: 2020-02
• Subjects: Circ_016719 -- miR-29c/Map2k6 -- Ischemia/reperfusion -- Apoptosis -- Autophagy; I/R ischemia/reperfusion -- OGD/R oxygen glucose deprivation and reoxygenation -- Map2k6 Rac-MAPK kinase 6 -- IAT intra-arterial thrombolysis -- MAPK mitogen-activated protein kinase -- miRNA microRNA -- circRNA circular RNA -- tMAO transient middle cerebral artery occlusion -- CCA common carotid artery -- ECA external carotid artery -- NC negative control -- CCK-8 Cell Counting Kit-8 -- PI Propidium Iodide -- FITC fluorescein isothiocyanate -- TUNEL Terminal-deoxynucleoitidyl transferase-mediated nick end labeling -- RT-PCR Real-time-PCR -- DAB 3, 3-diaminobenzidine -- TEM transmission electronic microscope; Molecular probes -- Diagnostic use -- Periodicals; Pathology, Cellular -- Technique -- Periodicals; Cell Biology -- Periodicals; Molecular Biology -- Periodicals; Sondes moléculaires -- Utilisation diagnostique -- Périodiques; Cytopathologie -- Technique -- Périodiques; 572
• DOI: 10.1016/j.mcp.2019.101478
• Languages: English
• ISSNs: 0890-8508

Abstract

Abstract: Background: Stroke is a leading cause of mortality worldwide. Rac-MAPK kinase 6 (Map2k6) plays important roles in cell proliferation and apoptosis. However, the role played by Map2k6 in stroke injury and the underlying mechanism of action remain unknown. Methods: Mice received cerebral ischemia/reperfusion (I/R) injuries by transient middle cerebral artery occlusion. HT22 cells were subjected to oxygen glucose deprivation and reoxygenation (OGD/R) to simulate an I/R injury. Subsequently, the levels of circ_016719, miR-29c and Map2k6 expression were determined, and their interactions were examined by luciferase assays. Circ_016719 knockdown, miR-29c inhibition or Map2k6 overexpression was induced in HT22 cells; after which, the cells were examined for their viability, apoptosis, autophagy and proliferation, as well their levels of Map2k6, p38, p53, LC3B–I, LC3B-II, Beclin 1, and p62 expression. Results: Significantly increased levels of circ_016719 and Map2k6, and decreased levels of miR-29c were observed in both in vivo and in vitro I/R injury models. In HT22 cells, circ_016719 knockdown significantly increased miR-29c expression and cell proliferation, but decreased Map2k6 expression and cell apoptosis. Additionally, significant increases in LC3B–I and p62 levels and decreased LC3B-II levels were observed, indicating that circ_016719 knockdown had significantly inhibited autophagy. Furthermore, additional inhibition of miR-29c markedly suppressed the effects of circ_016719 knockdown; however, that suppression was significantly attenuated by Map2k6 overexpression. Additionally, Map2k6 was identified as a direct target of miR-29c, which in turn, might be sponged by circ_016719. Conclusions: Our results suggest that circ_016719 directly targets miR-29c, and thereby regulates the expression and functions of Map2k6, which significantly contributes to the pro-apoptotic role of circ_016719. Highlights: Increased expression of Circ_016719 and Map2k6 were observed after I/R treatment. Decreased expression of miR-29c was observed in vivo and in vitro after I/R treatment. Decreased expression of Circ_016719 increased cell viability and decreased cell apoptosis after I/R treatment. Circ_016719 directly targeted miR-29c, which negatively mediated the pro-apoptotic effect of the circRNA. Map2k6 was a direct target of miR-29c, and resultantly mediate the effects of Circ_016719/miR-29c