Less Myostatin and More Lean Mass in Large-Born Infants From Nondiabetic Mothers

Context and Objective: Sexagenarians born large are at lower risk for type 2 diabetes than those born small, a key feature of their body composition being a higher muscle mass, which explains their higher body mass index and also their lower fat-to-lean-mass ratio. Myogenesis is completed in early infancy under the inhibitory control of myostatin. We tested whether large-born infants from nondiabetic mothers develop an early surplus of lean mass while having a lower myostatinemia. Design, Methods, Study Participants, and Main Outcomes: In a longitudinal study (0–4 mo), we compared the body composition and endocrine markers (fasting glucose, insulin, IGF-1, high molecular weight adiponectin) of breast-fed appropriate- vs large-for-gestational-age infants (n = 125) from nondiabetic mothers. Circulating myostatin concentrations were assayed after collection of the above-mentioned data. Setting: The study was conducted at the University Hospital for Women and Children. Intervention: There were no intervention...