ABSTRACT
The role and mechanism of vitamin D in fetal and neonatal lung development and chronic lung diseases development have raised attention in recent years. The placental transfer of vitamin D is the major source of vitamin D to the developing fetus. The lung, as a target organ for vitamin D, has its capacity for vitamin D metabolism and can form biologically active 1,25 dihydroxyvitamin D 3 in a paracrine manner to regulate lung development. Studies have shown that vitamin D is directly involved in the synthesis of lung surfactant proteins and phospholipids and promotes lung maturation such as lung epithelial-mesenchymal interactions and alveolar formation. Furthermore, it regulates immunity and improves placental function, which indirectly affects lung development. Vitamin D deficiency and vitamin D receptor polymorphisms have been found to be detrimental to the development of alveoli, and are associated with respiratory diseases such as neonatal respiratory distress syndrome and bronchopulmonary dysplasia (BPD). Experimental studies in animals have shown that antenatal vitamin D supplementation promotes lung maturation in preterm rats and postnatal vitamin D supplementation can alleviate the hyperoxia-induced inflammatory response in the lung and reduce BPD occurrence. Further high-quality research are needed to explore the dosing, timing, and impact factors of vitamin D for promoting fetal and neonatal lung maturation and clarify the mechanism of its prophylactic and therapeutic action.