<p>(A-B) The cells were pre-incubated in the presence or absence of SK-216 (50, 100 μM) for 1 hour and then co-incubated with TGF-β1 (5 ng/ml). After incubation for 24 hours, the cells and the supernatants of cell cultures were collected. (A) Active and total PAI-1 levels in the supernatants were measured using active and total PAI-1 ELISA kit. Results are expressed as the mean ± SEM of 4 samples. (B) PAI-1 mRNA expression in the cells was measured using real-time quantitative RT-PCR. Results are expressed as the mean ± SEM of 5 experiments. (C) The cells were pre-incubated in the presence or absence of SK-216 (100 μM) for 1 hour and then co-incubated with TGF-β1 (5 ng/ml). After incubation for 24 hours, the culture medium was replaced with serum-free medium. The supernatants of cell cultures were collected at 12, 24, and 48 hours after the medium change. Endogenous TGF-β1 was analyzed by measuring the concentration of TGF-β1 in the supernatants using TGF-β1 ELISA kit. Results are expressed as the mean ± SEM of 4 experiments. *p < 0.05, **p < 0.01, ***p < 0.001.</p
