Cyclic tensile strain promotes the ECM synthesis of cranial base synchondrosis chondrocytes by upregulating miR-140-5p.

ABSTRACT

OBJECTIVE: This study aimed to explore the role of miR-140-5p in cranial base synchondrosis chondrocytes (CBSCs) under cyclic tensile strain (CTS). SETTING AND SAMPLE POPULATION A total of 25 1-week-old Sprague Dawley rats from Shanghai Laboratory Animal Center, Chinese Academy of Sciences, were used. MATERIAL AND METHODS: The second passage of CBSCs was applied with CTS at 10% elongation (1 Hz) for 24 hours. MiR-140-5p levels in CBSCs were detected by qRT-PCR. The role of miR-140-5p in CBSCs was evaluated by transfection of mimics and inhibitor. RNA sequencing and online search of miRNA databases (TargetScan, miRDB and miRanda) were used in prediction of miR-140-5p targets. A luciferase reporter assay was applied to identify the target gene of miR-140-5p. RESULTS: Compared with the control, the expression of Col2a1 and Sox9 was significantly higher after CTS (P < .05). Also, CBSCs demonstrated higher expression of miR-140-5p after CTS loading for 24 hours (P < .05). Overexpression of miR-140-5p promoted ECM synthesis under CTS loading environment, while suppression of miR-140-5p inhibited the effect. Bloc1s2 was a putative target gene of miR-140-5p. CONCLUSIONS: The expression of ECM in CBSCs could be promoted by CTS and miR-140-5p might play a role in this process through targeting Bloc1s2.