Adiposity-dependent adipokine-immunoglobulin interplay in mature breast milk

Introduction Excessive maternal body fat (BF) accumulation promotes low-grade inflammation, altering milk adipokine and immunoglobulin profiles and potentially contributing to intergenerational immunometabolic programming of offspring. This observational study focused on mothers with higher BF and evaluated associations between adipokines and immune components in mature milk. Methods At 5 months of lactation (N = 59), concentrations of lactoferrin (LF), immunoglobulins (S-IgA, IgG, IgM), CRP, adipokines (leptin, adiponectin, and ghrelin), and the leptin-to-adiponectin ratio (LAR) were quantified in milk samples using an immunoenzymatic assay. ANCOVA models assessed associations between maternal BF categories (high vs normal) and milk adipokines and immunological components. Results Mature milk from mothers with higher BF showed significantly higher concentrations of CRP (8.00 vs 3.44 μg/L), leptin (0.41 vs 0.14 μg/L), LAR (0.13 vs 0.05), and IgM (2.78 vs 1.59 mg/L) than the normal BF group. ANCOVA models revealed positive associations between milk leptin and LF (β=0.51, p = 0.022) and S-IgA (β=0.47, p = 0.014), as well as LAR and LF (β=0.37, p = 0.032). No significant differences in adiponectin, ghrelin, LF, S-IgA, or IgG concentrations were observed between the analyzed groups. Elevated maternal BF is associated with higher levels of breast milk inflammatory markers (CRP, leptin), LAR, and IgM, suggesting metabolically induced inflammation. Discussion Leptin-immunoactive component associations (S-IgA, LF) offer novel insights into milk bioactivity. These findings highlight the role of metabolic-immunological milk components in shaping health trajectories for infants of mothers with elevated BF.