Figure 1.

Effect of high-frequency near-infrared diode laser irradiation on interleukin (IL) -1β-induced gene expression of inflammatory cytokines in Normal Human Articular Chondrocyte-Knee (NHAC-Kn) cells. The chondrocytes were treated with IL-1β (10 pg/mL) and laser irradiated (0, 4, 8 J/cm²) for 4 h, followed by real-time Polymerase Chain Reaction (PCR) analysis. mRNA expression of (A) IL-1β, (B) IL-6, and (C) tumor necrosis factor (TNF) -α are represented as mean ± SEM of three independent experiments (n = 3). * p < 0.05 compared to the IL-1β group.