MiR-1246 Promotes LPS-Induced Inflammatory Injury in Chondrogenic Cells ATDC5 by Targeting HNF4γ

Background/Aims: Osteoarthritis (OA) is a common inflammatory joint disease. miRNAs are associated with OA and functionally implicated in the pathogenesis of the disease. In the present study, we investigated the role of miR-1246 in the lipopolysaccharide (LPS)-induced inflammatory injury of ATDC5 cells. Methods: ATDC5 cells were cultured and treated with LPS in a series of concentration (0, 1, 5, and 10 mu g/ml) for 5 h. The cells were transfected with miR1246-mimic, inhibitor, si-HNF4 gamma or negative control, then were assessed for cell viability using CCK8 assay, apoptosis by flow-cytometry and expressions of miR-1246 and pro-inflammatory cytokines by qRT-PCR and western blot analysis. Results: Cell viability was significantly reduced and cell apoptosis was added in ATDC5 cells injured with LPS at the dosage of 5 and 10 mu g/ml. Relative mRNA expressions of pro-inflammatory cytokines (IL-1 ss, IL-6, IL-8 and TNF-alpha) were significantly increased. miR-1246 was up-regulated in ATDC5 cells treated with LPS. Moreover, miR-1246 overexpression aggravated LPS-induced decrease in cell viability, increase in apoptosis and overproduction of pro-inflammatory factors. mRNA and protein expressions of HNF4 gamma were significantly suppressed in cells transfected with miR-124-mimic. Further, miR-1246 knockdown alleviated LPS-induced inflammatory injury by up-regulating the expression of HNF4. and activation of PI3K/AKT and JAK/STAT pathways. Conclusions: Suppression of miR-1246 alleviated LPS-induced inflammatory injury in chondrogenic ADTC5 cells by up-regulation of HNF4 gamma and activation of PI3K/AKT and JAK/STAT pathways. The findings of this study will provide a novel viewpoint regarding miR-1246 target for clinical. (C) 2017 The Author(s) Published by S. Karger AG, Basel