Long non‑coding (lnc)RNA KCNQ1 opposite strand/antisense transcript 1 (Kcnq1ot1) has been shown to regulate multiple biological processes. However, the functional role of Kcnq1ot1 in osteoporosis and the underlying mechanism are still unclear. The present study aimed to investigate the function of lncRNA Kcnq1ot1 in osteogenic differentiation. Alkaline phosphatase (ALP) activity was measured using an ALP assay kit. Western blotting was performed to assess the expression levels of osteogenic differentiation‑associated proteins. Reverse transcription‑quantitative PCR was performed to detect Kcnq1ot1, microRNA (miR)‑98‑5p and T‑box transcription factor 5 (Tbx5) expression levels. The binding of Kcnq1ot1 with miR‑98‑5p and that of miR‑98‑5p with Tbx5 were predicted by starBase and TargetScan databases, respectively, and verified using dual luciferase reporter assays. The mineralization of MC3T3‑E1 cells was observed using an Alizarin red S staining assay. The results revealed that expression of Kcnq1ot1 was increased and that of miR‑98‑5p was decreased during osteogenic differentiation. Additionally, Kcnq1ot1 was shown to target miR‑98‑5p and inhibit its expression. Inhibiting miR‑98‑5p reversed the inhibitory effect of Kcnq1ot1 knockdown on osteogenic differentiation and mineralization of MC3T3‑E1 cells. Furthermore, Kcnq1ot1 regulated Tbx5 expression via miR‑98‑5p. Overexpressing miR‑98‑5p or downregulating Tbx5 expression reversed the promotive effect of Kcnq1ot1 overexpression on osteogenic differentiation and mineralization of MC3T3‑E1 cells. In conclusion, these findings suggested that Kcnq1ot1 may promote bone formation by inhibiting miR‑98‑5p and upregulating Tbx5. Kcnq1ot1, miR‑98‑5p and Tbx5 may therefore serve as promising targets for the treatment of osteoporosis.
Yuan Haojie,Yu Junbo,Liu Chun,Zhao Heyan,Xue Jianhua,Liu Jiajia,Yang Yang
This study aims to discuss the role of exosomes KCNQ10T1 derived from bone marrow mesenchymal stem cells (BMMSCs) in sepsis and to further investigate its potential molecular mechanisms. Exosomes extracted from BMMSCs are identified by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and western blot. Fluorescence labeling is applied to detect the internalization of exosomes in receptors. The proliferation ability, migration ability, and invasion ability of HUVECs are determined by CCK-8, EdU, wound healing, and Transwell. The levels of inflammatory cytokines in sepsis cells are quantitatively detected by ELISA. Kaplan–Meier survival curve is used to describe the overall survival. RT-qPCR is used to detect mRNA expression of related genes. Bioinformatics analysis is performed to search the downstream target of KCNQ1OT1 and miR-154-3p and the interaction is verified by luciferase reporter assay. Exosomes derived from BMMSCs alleviated the toxicity in sepsis cell models and animal models. In mice with septic cell models, exosomal KCNQ10T1 was down-regulated and associated with lower survival. Overexpression of KCNQ10T1 inhibited the proliferation and metastasis of LPS-induced HUVECs. Further research illustrated that miR-154-3p was the downstream target gene of KCNQ1OT1 and RNF19A was the downstream target gene of miR-154-3p. Importantly, functional research findings indicated that KCNQ1OT1 regulated sepsis progression by targeting miR-154-3p/RNF19A axis. Our study demonstrates that the exosomal KCNQ1OT1 suppresses sepsis via mediating miR-154-3p/RNF19A, which provides a latent target for sepsis treatment.