Figure 4.

Resistin modulates claudin-5 and occludin expression through the AMPK/mTOR pathway. PAECs were treated or untreated with AMPK activator (Metformin) or mTOR inhibitor (KU-0063794) for 2 h before being stimulated or unstimulated with recombined resistin protein (2.5, 5, or 0 nM) for 2 h. mRNA levels of claudin-5 and occludin were analysed using qRT-PCR (a-d) and protein levels were analysed using western blot analysis (e, f); the mRNA levels of each gene were standardized to GAPDH. The antibodies were diluted as previously described. β-actin served as a loading control, and the relative protein level was calculated with ImageJ software and normalized to β-actin. **p<0.01 and ^##p<0.01 compared with the resistin-treated (without inhibitors) group. Error bars represent the mean ± SEM (n = 3). (g) TEER of PAECs was measured at 0, 6, 12, 24, 48, and 2 h after recombined resistin protein treatment (0 nM). The TEER levels were displayed as a percentage of the TEER before treatment. **p<0.01 compared with the untreated group. Error bars represented the mean ± SEM (n = 3).