Introduction: LPS-induced inflammation contributes to osteoarthritis (OA). It is known that Circ_0038467 plays a critical role in LPS-mediated inflammation, suggesting the its involvement in OA. This study aimed to study the possible involvement of Circ_0038467 in OA.Materials and Methods: Circ_0038467, mature miR-203 and miR-203 precursor expression in controls and OA patients was determined by RT-qPCR. Circ_0038467 overexpression in chondrocytes and RT-qPCR was performed to analyze its effects on the expression of mature miR-203 and miR-203 precursor. The role of Circ_0038467 and miR-203 in cell apoptosis was analyzed by cell apoptosis assay.Results: Circ_0038467 was upregulated in OA and positively correlated with mature miR-203, but not miR-203 precursor. In chondrocytes, increased expression of both Circ_0038467 and miR-203 was observed after LPS treatment. In chondrocytes, Circ_0038467 overexpression increased the expression levels of mature miR-203, but not miR-203 precursor. Analysis of cell apoptosis showed that overexpression of Circ_0038467 and miR-203 increased cell apoptosis. In addition, miR-203 inhibitor reversed the effects of Circ_0038467 overexpression on cell apoptosis.Conclusions: Circ_0038467 is highly expressed in OA and may promote the production of mature miR-203 to increase the apoptosis of chondrocytes induced by LPS.

Circ_0038467 and miR-203 exert important functions in lipopolysaccharide (LPS)-induced inflammation, which contributes to osteoarthritis (OA). Our preliminary deep sequencing analysis revealed altered expression of Circ_0038467 and miR-203 in OA and a close correlation between them. This study was therefore to explore crosstalk between them in OA. The expression of Circ_0038467, mature miR-203, and miR-203 precursor in OA patients and controls was determined using RT-qPCR. An overexpression assay was performed to explore the role of Circ_0038467 in regulating the expression of mature miR-203 and miR-203 precursor. Cell apoptosis was analyzed by cell apoptosis assay. Circ_0038467 was upregulated in OA and positively correlated with mature miR-203 but not that of miR-203 precursor. In chondrocytes, increased expression levels of both Circ_0038467 and miR-203 were observed after LPS treatment. In chondrocytes, overexpression of Circ_0038467 increased the expression levels of mature miR-203 but not that of miR-203 precursor. Overexpression of Circ_0038467 and miR-203 increased cell apoptosis. Then, the miR-203 inhibitor reversed the effects of overexpression of Circ_0038467 on cell apoptosis. Interestingly, Circ_0038467 was detected in both the cytoplasm and nucleus. Circ_0038467 directly interacted with the precursor miR-203. Therefore, Circ_0038467 is highly expressed in OA and it may promote the production of mature miR-203 to increase apoptosis of chondrocytes induced by LPS.