ABC Transporters in Human Placenta and Their Role in Maternal-Fetal Cholesterol Transfer: ABCA1 Candidate Target

Placenta is the highly specialized organ of pregnancy, in association with the fetal membranes and amniotic fluids; placenta supports normal fetal growth and development. Primary function of the placenta in all species is to selective transfer of nutrients and waste products between mother and fetus. It participates in the transfer and metabolism of carbohydrates, amino acids, lipids, water, inorganic ions, minerals and vitamins. Respiratory gases also transfer between mother and fetus through placenta. Another important function of placenta is the endocrine function. Adequate nutrient transfer by placenta between mother and fetus during pregnancy is crucial for proper fetal growth and development. Among all nutrients, cholesterol is important as well for proper fetal growth. Embryo and fetal growth phase is the rapid cellular proliferative stage. In this phase, cells differentiate into various cell types. That’s why; cells need all the substrates for their proper growth. As long as cells are proliferating, the important cellular structure such as membrane is also vital for the proliferative cells. One of the principal and key components of cell membrane is cholesterol. Cholesterol maintains membrane fluidity and lipid rich microdomain. Any alteration of cellular cholesterol content may lead to diverse complication in different metabolic processes. Cholesterol is the precursor of bile acids, steroid hormones and metabolic regulators such as oxysterols.