The Concentration of Liver-Expressed Antimicrobial Peptide 2 in Human Milk and Infant Plasma Is Positively Associated with Adiposity and Body Weight in the First Year of Life.

Background: The liver-expressed antimicrobial peptide 2 (LEAP2) is a recently recognized anorectic and glucose-regulating hormone with an unknown role in lactation.

Objectives: The objectives of this study were as follows: 1) to assess LEAP2 presence in human milk and putative associations with infant body weight and adiposity in the first year of life, 2) to evaluate the impact of maternal weight status on LEAP2 concentration, and 3) to explore the relationship between infant plasma LEAP2 concentration and body weight and adiposity.

Methods: This prospective cohort observational study assessed LEAP2 concentration in plasma and milk from lactating women with normal weight (n = 26) or overweight or obesity (OW/OB, n = 26) at 6 mo postpartum and in 6-mo-old infant plasma, examining associations with metabolic and anthropometric variables at 6 mo and 1 y.

Leptin receptor expression in blood mononuclear cells of lactating women is associated with infant body weight: Potential role as a molecular biomarker.

Background: Molecular biomarkers of maternal leptin resistance associated with infant weight are needed.

Objectives: To evaluate gene expression of leptin receptor (LEPR), suppressor of cytokine signalling 3 (SOCS3) and insulin receptor in peripheral blood mononuclear cells (PBMCs) of lactating women and their relationship with infant body weight and adiposity.

Methods: At day 10 postpartum, maternal gene expression in PBMCs as well as leptin and insulin concentrations in plasma and milk were assessed (n = 68).