Fig. 8: Neutralizing antibody-mediated Musclin blockade improves energy homeostasis.

WT male mice were treated with saline or Musclin Antibody (Musclin Ab). a Schematic of in vitro validation of Musclin antibody and in vivo Musclin neutralization assay. b qPCR analysis of C3H10T1/2-derived adipocytes pretreated with control IgG or Musclin Ab, followed by treatment with forskolin. n = 3 per group. c–f Chow diet-fed mice were treated with saline or Musclin Ab beginning at 3 months old. n = 5 per group. c Body weight gain. d Weight of indicated tissues. e Representative H&E staining images of iWAT (left) and average adipocyte size analysis (right). f Immunoblots of total lysates from iWAT (left), and quantification of protein levels (right). g–i Chow diet-fed mice were treated with saline or Musclin Ab beginning at 2.5 months old and continued for 3 months. Saline vs Musclin Ab, n = 5 vs 6. g Oxygen consumption rate of 3 consecutive days monitored at RT (24°C) following thermoneutrality at 30°C (1 week) and an additional 2 days of adaptation at RT. Lean mass was applied for normalization. h Average oxygen consumption rate at day time or night time during the 3 days of monitoring as in (g). i Average energy expenditure at day time or night time. j Core body temperature of HFD-fed mice during acute cold exposure at 4°C. n = 8 per group. HFD feeding began at 2.5 months old with antibody treatment (for 1 month) after 5.5 months old. k Blood glucose levels. Saline vs Musclin Ab, n = 9 vs 8. HFD feeding began in mice at 3.5 months old with antibody treatment (for 2 weeks) at 4.5 months old. l Glucose tolerance test (left) and the AUC (right). n = 8 per group. HFD feeding began in mice at 3.5 months old with antibody treatment (for 1 month) at 4.5 months old. b Data represent mean ± SD (n represents biologically independent cell samples); c–l data represent mean ± SEM (n represents biologically independent animals). b, one-way ANOVA with Tukey’s multiple comparisons. c, j two-way ANOVA with Sidak’s multiple comparisons. d-f, h, i, k, l Two-tailed unpaired Student’s t-test. Experiments in b, f, j, k were repeated independently three times, and results in c–e, g–i, l were repeated independently twice with similar results. Source data are provided as a Source Data file.