Neonatal overfeeding promotes rapid weight gain and increases adiposity without causing WAT inflammation at weaning.

A: Pre-weaning growth curves (body weights) of mice raised in normal litters (NL) or small litters (SL) (n = 19–25 per group from ≥ 9 litters). B-C: Mass (B) and mean adipocyte areas (C) of epididymal (eWAT) and subcutaneous (sWAT) adipose tissue of P21 SL and NL mice (n = 4–5 per group from ≥ 5 litters). D-E: Representative images showing adipocyte morphology (immunostained for perilipin, green fluorescence) and F4/80-immunoreactive cells (red fluorescence) in eWAT (D) and sWAT (E) of NL and SL mice at P21. F: Quantification of F4/80-immunoreactive cells in eWAT (D) and sWAT (E) of NL and SL mice at P21 (n = 4–5 per group from ≥ 4 litters). G-H: Relative gene expression of macrophage markers (G) and cytokines (H) in sWAT at P21. I-K: Plasma levels of TNF-α (I), glucose (J), and insulin (K) in NL and SL mice at P21 (n = 4–5 per group from ≥ 4 litters). *P<0.05 and **P<0.01 versus NL. Scale bar, 100 μm.