Fig. 3
From: Exosomes of pasteurized milk: potential pathogens of Western diseases
Dairy milk exosomes and fetal macrosomia. Milk exosome-derived miR-21 may increase placental miR-21 content promoting mTORC1 signaling via inhibition of phosphatase and tensin homolog (PTEN) and other regulatory checkpoints. Increased mTORC1-mediated placental growth enhances the nutrient transfer to the fetus. In the trophoblast, upregulated mTORC1 increases the expression of L-type amino acid transporters (LAT) and glucose transporter 1 (GLUT1), thus overstimulating the diaplacental flux of branched-chain amino acids (BCAAs) and glucose to the fetus promoting fetal overgrow (macrosomia). miR-21 also targets CDKN1C, a critical checkpoint for fetal growth mutated in Beckwith-Wiedemann syndrome