[Expression and significance of β-catenin and NF-κB signaling pathway in knee osteoarthritis synovial inflammation].

Objective: To explore expression of β-catenin and NF-κB signaling pathway in synovial tissue of rats with different degrees of knee osteoarthritis (KOA).

Methods: Forty-eight SPF male rats weighed (200±20) g were randomly divided into three groups, namely model group (32 rats), sham operation group (8 rats) and control group (8 rats). KOA model rats were established by Hulth method, and 8 rats were killed at 2, 4, 8, 12 weeks respectively after modeling, in order to establish KOA model rats with moderate, early, mild and severe degree. Sham operation group was only cut off capsule of knee joint and suture to exclude interference factor, control group was untreated. Behavior, synovial hyperplasia and cartilage degeneration of rats among each group were observed. Expression of NF-κB and signaling pathway and β-catenin in synovial tissue of rats were detected by real-time PCR.

Results: KOA rat model was successfully established, and synovial hyperplasia was observed in KOA model at mild and early degree, and then gradually decreased; while cartilage degeneration in the early moderate and severe KOA model was significantly expressed, and gradually aggravated with time. The results of PCR showed that expression of β-catenin in 4-week group (8.57±0.46) and 8-week group (4.23±0.09) were higher than those in control group (<0.05); expression of TLR-2 in 2-week group (12.04±4.02) and 4-week group (8.54±2.13) were higher than those in control group(<0.05), and TLR-4 in 2-week group(5.04±0.93), 4-week group (3.29±0.58) and 8-week group (1.63±0.12) were higher than those in control group; expression of NF-κB was significantly higher in 2-week group (10.15±2.04), 4-week group (15.97±4.17), 8-week group (7.69±1.48) and 12-week group (6.70±1.58) than that in control group (<0.05), and expression of IL-1β was significantly higher in 4-week group (2.79±0.25) and 8-week group (2.46±0.32) than that of control group (<0.05).

Conclusions: On the RNA expression level, both of β-catenin and NF-κB signaling pathways are involved in synovial inflammation in KOA model rats, and they play a regulatory role in expression of IL-1β, degeneration of KOA.