Fig. 7.

Metformin-mediated lipogenic differentiation in human IPF lung fibroblasts is mediated by BMP2 signaling. a–c Western blot showing the opposing effects of metformin and rhTGFβ1 on PPARγ phosphorylation and the ability of metformin to partially restore PPARγ phosphorylation in rhTGFβ1-treated IPF fibroblasts. Lanes 1–12 and lanes 13–18 were run in parallel on different gels under the same conditions. d Western blot showing the phosphorylation status of SMAD1/5/8 in the presence of metformin and/or the BMP signaling inhibitor noggin. Quantification of the immunoblot is shown in (e). f–h qPCR analysis of PLIN2, PPARg, and COL1A1 in IPF fibroblasts treated with vehicle, metformin, noggin and noggin + metformin. Each data point corresponds to one patient and error bars indicate s.e.m. a–c n = 3 per group. d Vehicle- and noggin-treated groups: n = 3 per group, metformin- and metformin/noggin-treated groups: n = 4. f–h n = 4 per group. Kruskal–Wallis test was used in (b, c, e–h). *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001