Fig. 6: The low body adiposity of HSP47 ablations is attributed to the decreased stability and activity of PPARγ.

Western blot image (a) of FAK signal and PPARγ proteins in 3T3-L1 adipocytes treated with FAK inhibitor (PF-573228; FAKi; 0.5 and 1 µM; n = 3 each) for 3 h; the densitometry graph (b; control vs 0.5 µM, p = 0.0063; control vs 1 µM, p < 0.0001) of PPARγ protein. Western blot image (c) of focal adhesion kinase (FAK) signal in 3T3-L1 adipocytes after FAKi (1 µM) treatment with cycloheximide (50 ug/ml) for 0, 30, 60, and 90 min; the densitometry graph (d) of PPARγ protein. e Western blot image of ubiquitinated PPARγ protein in FLAG-PPARγ and HA-Ub overexpressed HEK293T cells after FAKi (10 µM) treatment with/without MG132 (10 µM) for 3 h. f Western blot image of FAK signal and PPARγ proteins in 3T3-L1 adipocytes after FAKi (1 µM) treatment with/without MG132 (10 µM) for 0, 2 and 3 h. Western blot image (g) of FAK signal and PPARγ proteins in 3T3-L1 adipocytes after FAKi (1 µM) treatment with/without MDM2i (MI-773; 0, 1, 2, and 4 µM) for 3 hours; the densitometry graph (h; Control vs FAKi, p < 0.0001; FAKi vs FAKi + MDM2i 4 µM, p = 0.0289) of PPARγ protein. i Western blot image of ubiquitinated PPARγ protein in FLAG-PPARγ and HA-Ub overexpressed HEK293T cells after HSP47i (200 µM) treatment with/without MG132 (10 µM) for 3 h. j Western blot image of FAK signal and PPARγ proteins in 3T3-L1 adipocytes after HSP47i (200 µM) treatment with/without MG132 (10 µM) for 0, 2 and 3 h. Western blot image (k) of FAK signal and PPARγ proteins in 3T3-L1 adipocytes after HSP47i (200 µM) treatment with/without MDM2i (MI-773; 0, 2, and 4 µM) for 3 h; the densitometry graph (l; Control vs HSP47i, p = 0.0002; HSP47i vs HSP47i + MDM2i 4 µM, p = 0.0073) of PPARγ protein. m Realtime qPCR data of PPARγ and the target genes (Adipoq, p = 0.01045; Fabp4, p = 0.007259; Cd36, p = 0.048212; Lpl, p = 0.051; Scd1, p = 0.016136) in 3T3-L1 adipocytes after HSP47i (200 µM) treatment for 3 h (n = 3 each). n Realtime qPCR data of PPARγ and the target genes (Adipoq, p = 0.0065, Cd36, p = 0.017; Lpl, p = 0.0196; Scd1, p = 0.000272) in in vivo mouse adipose tissue (epididymal fat) after HSP47i (100 mg/kg; single shot followed by 24 h fasting and 24 h refeeding) treatment (n = 4 each). White adipose tissue (WAT) mass (o the total mass of epididymal and inguinal fat; p WAT percentage per body weight) of control (Ctrl) and AdHSP47KO (KO) with/without pioglitazone (pio; 15 mg/kg; every other day for a week) treatment (Ctrl n = 17; KO n = 12; KO + Pio n = 10). The total mass of WAT, Ctrl vs KO, p = 0.0096; KO vs KO + Pio, p = 0.0068. WAT percentage, Ctrl vs KO, p = 0.0395. q, r White adipose tissue (WAT) mass (q; total mass of WAT, r; WAT percentage) of control (Ctrl) and HSP47i (100 mg/kg) with/without pioglitazone (pio; 30 mg/kg) treatment (n = 5 each). WAT total mass, Ctrl vs HSP47i, p = 0.0122; HSP47i vs HSP47i + Pio, p = 0.0122. WAT percentage, Ctrl vs HSP47i, p < 0.0001; HSP47i vs HSP47i + Pio, p = 0.0189. Data represent the mean ± SEM. *p < 0.05, **p < 0.01, and ***p < 0.001; n refers to sample size. Statistical significance was determined by Tukey–Kramer test (h and l), two-tailed unpaired t-test (m and n), and Wilcoxon test (o–r). Source data are provided as a Source Data file.