Abstract
Numerous studies have previously demonstrated that long non‑coding RNAs (lncRNAs) serve an important regulatory role in osteoarthritis (OA). In particular, the lncRNA family with sequence similarity 201 member A (FAM201A) was previously found to be downregulated in necrotic femoral head samples. However, the role of FAM201A in IL‑1β‑induced chondrocyte injury remains unclear. It was hypothesized that FAM201A may exert a protective effect on IL‑1β‑induced chondrocyte injury in OA by sponging microRNAs (miRNAs/miRs). The purpose of the present study was to explore the role and molecular mechanism of FAM201A in IL‑1β‑induced chondrocyte injury. A model of OA was established by stimulation C‑28/I2 cell with IL‑1β in vitro. The expression levels of FAM201A following IL‑1β‑induced chondrocyte injury were detected via reverse transcription‑quantitative PCR. Luciferase reporter assay was used to assess the possible associations among FAM201A, miR‑146a‑5p and POU class 2 homeobox 1 (POU2F1). Chromatin immunoprecipitation assay was performed to analyze the interaction between POU2F1 and miR‑146a‑5p. ELISA, TUNEL and western blotting were performed to measure the level of inflammation, lactate dehydrogenase release, apoptosis and the expression of apoptosis‑related proteins (Bcl‑2, Bax, cleaved caspase 3 and cleaved caspase 9), respectively. The expression levels of FAM201A were found to be downregulated following IL‑1β‑induced chondrocyte injury. Overexpression of FAM201A exerted a protective effect against IL‑1β‑induced chondrocyte injury. In addition, FAM201A could upregulate the expression levels of POU2F1 by sponging miR‑146a‑5p. Further experiments revealed that POU2F1 could bind to the promoter region of FAM201A and subsequently regulate the expression levels of POU2F1, indicating a role for the FAM201A/miR‑146a‑5p/POU2F1 positive feedback loop in IL‑1β‑induced chondrocyte injury. The present study revealed the protective effects of the FAM201A/miR‑146a‑5p/POU2F1 positive feedback loop on IL‑1β‑induced chondrocyte injury and provided a potential therapeutic target for OA.