Prevalence of obesity among infants and children below 5 years of age is rising dramatically, and early childhood obesity is a forerunner of obesity and obesity-associated diseases in adulthood. Childhood obesity is hence one of the most serious public health challenges today. Here, we have identified a mother-to-child lipid signaling that protects from obesity. We have found that breast milk–specific lipid species, so-called alkylglycerol-type (AKG-type) ether lipids, which are absent from infant formula and adult-type diets, maintain beige adipose tissue (BeAT) in the infant and impede the transformation of BeAT into lipid-storing white adipose tissue (WAT). Breast milk AKGs are metabolized by adipose tissue macrophages (ATMs) to platelet-activating factor (PAF), which ultimately activates IL-6/STAT3 signaling in adipocytes and triggers BeAT development in the infant. Accordingly, lack of AKG intake in infancy leads to a premature loss of BeAT and increases fat accumulation. AKG signaling is specific for infants and is inactivated in adulthood. However, in obese adipose tissue, ATMs regain their ability to metabolize AKGs, which reduces obesity. In summary, AKGs are specific lipid signals of breast milk that are essential for healthy adipose tissue development.
Haidong Yu, Sedat Dilbaz, Jonas Coßmann, Anh Cuong Hoang, Victoria Diedrich, Annika Herwig, Akiko Harauma, Yukino Hoshi, Toru Moriguchi, Kathrin Landgraf, Antje Körner, Christina Lucas, Susanne Brodesser, Lajos Balogh, Julianna Thuróczy, Gopal Karemore, Michael Scott Kuefner, Edwards A. Park, Christine Rapp, Jeffrey Bryant Travers, Tamás Röszer