Figure 3.

(A) hACs were treated with Vehicle (Control), TGF-β1 (5 ng/ml), or BMP2 (100 ng/ml) for 72 h and mitochondrial respiration was represented by the OCR (pMoles/min) and measured by the Seahorse XF Extracellular Flux Analyser. OCR was measured approximately every 8 minutes over the course of the 145-minute mitochondrial stress test. Basal respiration was measured over the first 30 minutes before the addition of any treatment, and maximal respiration was measured after FCCP treatment for 30 minutes until Antimycin A + Rotenone treatment was given to inhibit mitochondrial respiration. (B) Boxplots of basal and maximal respiration of cell cultures by treatment. The mean basal OCR of control, TGF-β1– and BMP2-treated cells was 47.3 pMoles/min, 53.2 pMoles/min and 87.8 pMoles/min, respectively. Mean basal OCR of BMP2-treated cells was significantly higher than that of the control. The mean maximal OCR of control, TGF-β1– and BMP2-treated cells was 73.6 pMoles/min, 77.9 pMoles/min and 160.2 pMoles/min, respectively. Mean maximal OCR of BMP2-treated cells was significantly higher than that of the control. Data are shown as means ± SD of four independent experiments (*p < 0.05 by two-tailed t test).

OA = osteoarthritis; OCR = oxygen consumption rate; SD = standard deviation.