2022, Vol. 26 ›› Issue (35): 5607-5613

The mechanism of lncRNA HOTAIR in interleukin-1beta-mediated osteoarthritis

Zhou Liang1, Chen Xingzhen2, Li Zhenyu1, Zhang Zekun1, Duan Guoqing3   

Abstract: BACKGROUND: The articular cartilage of patients with osteoarthritis and normal human articular cartilage have been studied and found that long non-coding RNA (lncRNA) HOTAIR is significantly up-regulated compared with the control group, which may be related to the occurrence of osteoarthritis.
OBJECTIVE: To explore the mechanism of lncRNA HOTAIR in interleukin-1β-mediated osteoarthritis.
METHODS: (1) Clinical grouping: The medial condyle cartilage samples of 20 patients with arthritis who underwent total knee replacement were selected as experimental group. The articular cartilage samples of seven patients with lower extremity amputation or undergoing total hip arthroplasty due to femoral neck fracture were selected as control group. (2) Animal grouping: Forty-eight Sprague-Dawley rats were randomized into osteoarthritis group (n=36) and normal control group (n=12). Animal models of knee osteoarthritis were made in the osteoarthritis group. (3) Cell testing and treatment: The rat articular chondrocytes (RCCs-1) cultured in vitro were divided into control group, interleukin-1β group (the best mass concentration of 10 μg/L was selected to simulate osteoarthritis environment), small interfering RNA (siRNA) group, interleukin-1β+siRNA group. Except for the control group with no special treatment, the other groups were treated with corresponding solutions and cultured for 48 hours. (4) Detection indicators: At 4, 6, and 8 weeks after modeling, the rat femurs were collected for pathological observation using hematoxylin-eosin staining. RT-PCR was used to analyze the mRNA expression of lncRNA HOTAIR in interleukin-1β-mediated rat chondrocytes, rat articular cartilage, and the articular cartilage of patients. Chondrocyte viability was detected by cell counting kit-8 method. Expression of type II collagen in chondrocytes was detected by western blot. Apoptosis of chondrocytes was detected by flow cytometry.
RESULTS AND CONCLUSION: (1) The chondrocytes of the rats in the normal control group were neatly arranged, the cartilage structure was clear, and the tide line was complete. In the osteoarthritis group, the cartilage structure became more disordered over time, the number of chondrocytes was significantly reduced, the cartilage matrix was decolorized, and the tide line was badly disordered. (2) lncRNA HOTAIR expression was increased in the chondrocytes of both patients and rats with osteoarthritis. (3) Interleukin-1β reduced the viability of chondrocytes and increased the HOTAIR expression in rat knee joint. (4) HOTAIR inhibited the viability of chondrocytes and the expression of type II collagen in rat knee joint. (5) The expression of HOTAIR promoted apoptosis in chondrocytes. (6) To conclude, inhibition of HOTAIR-mediated chondrocyte apoptosis may be the potential mechanism of gene therapy for knee osteoarthritis.
Key words: knee joint, osteoarthritis, LncRNA, HOTAIR, interleukin-1β, apoptosis, type II collagen, cell proliferation