Adipose FoxO1 ablation tunes down Tgfβ1 signaling in adipocyte transdifferentiation.

(A) adO1KO mice exhibited downregulation of genes involved in Tgfβ1 signaling pathway in gonadal adipose tissue. (B–C) The effects of FoxO1 deletion on the key proteins Tgfbr2 and Smad3 in Tgfβ1 signaling pathway in gonadal adipose tissue, analyzed by Western blotting (B) and densitometry (C), n = 6. (D–G) The effects of Tgfβ1 and FoxO1 inhibition on iron import (TfR1) and export (ferroportin, Fpn) proteins, and beige marker Ucp1 protein in C3H/10T1/2 adipocytes, evaluated by Western blotting (D) and densitometry (E–G), n = 3. (H–J) The effects of Tgfβ1 and FoxO1 inhibition on cellular respiration control ratio (panel H), mitochondrial spare respiration capacity (panel I), and fatty acid oxidation activities (panel J) in C3H/10T1/2 adipocytes, analyzed by high resolution respiratory, n = 4. (K) Representative images (200x magnification) of C3H/10T1/2 adipocytes without treatment, treated with Tgfβ1, and co-treated with Tgfβ1 and FoxO1 inhibitor AS. (L) The effects of Tgfβ1 and FoxO1 inhibition on the size and population of lipid droplets in C3H/10T1/2 adipocytes, n = 4. *, p < 0.05; **, p < 0.01; ***, p < 0.001; n.s., not significant.