Fig. 3: GDF3 loss of function leads to decreased lipolysis.

A, B Free fatty acid (FFA) release from iWAT and eWAT explants of Gdf3^fl/fl and Gdf3^KO mice on HFD (from Fig. 1) at baseline and following isoproterenol stimulation (n = 10 Gdf3^fl/fl, 11 Gdf3^KO). C, D FFA release from iWAT and eWAT explants of Gdf3^fl/fl and Gdf3^AKO mice (from Fig. 2) at baseline and following isoproterenol (n = 4). E–M Primary adipocytes from differentiated stromal vascular fractions (SVF) of iWAT of Gdf3^fl/fl and Gdf3^fl/fl::RosaCre^ERT2/− mice, treated with 4-hydroxytamoxifen (4-OHT) to generate Gdf3^fl/fl and Gdf3^KO cells. E Gdf3 mRNA levels (n = 4). F FFA release at baseline and following isoproterenol stimulation for 2 h (n = 3). G, H Western blot analysis following isoproterenol stimulation. G Protein expression of phosphorylated protein kinase A (p-PKA) substrates, β3- adrenergic receptor 3 (β3-AR) and β-actin (loading control) (n = 1 per time point). H Left: Protein expression of phosphorylated hormone-sensitive lipase at serine 660 (pHSL Ser 660) corresponding total HSL and β-actin levels without (basal) and with isoproterenol (stimulated) for 15 min. Right: Relative band intensities of pHSL versus total HSL quatified from the left panel, (n = 3). I RTqPCR analysis of Adrb3 in response to isoproterenol stimulation (n = 6). J Relative cAMP levels in response to isoproterenol stimulation (n = 3). K Relative FFA release in response to isoproterenol or 8-Bromo-cAMP at indicated time points (n = 3). L Immunofluorescence (IF) staining of β3-AR (red), 5 min post isoproterenol stimulation. Nuclear stain: DAPI (blue). M IF staining of cyclic AMP (cAMP) (purple), 15 min post isoproterenol stimulation. Nuclear stain: DAPI (blue). A–F, H–K) Data are presented as mean values +/− SEM, ns = not significant. Statistical comparisons were made using two way ANOVA with Sidak’s multiple comparisons test (A–D, F, H) or unpaired two-tailed Student’s t-test (E, I–K) for each time point. Source data are provided as a Source Data file.