Figure 1.

Cortisol downregulates the level of collagen type I in HDFs. HDFs were treated with different concentrations of cortisol (0, 1, 10 and 100 nM) and cultured for 24 h. (A) Cell viability was determined using the CCK-8 assay. (B) Total RNA was extracted from cells and relative col1a1 mRNA levels were measured by qRT-PCR. (C) Culture media were harvested and the levels of procollagen type I were determined using a specific ELISA kit. All data represent the mean ± SD of three independent experiments. Significant differences: # p < 0.05, ## p < 0.01, ### p < 0.005 compared with the control.