The Placental Role in Gestational Diabetes Mellitus: A Molecular Perspective

Abstract

During pregnancy, women undergo several metabolic changes to guarantee an adequate supply of glucose to the foetus. These metabolic modifications develop what is known as physiological insulin resistance. When this process is altered, however, gestational diabetes mellitus (GDM) occurs. GDM is a multifactorial disease, and genetic and environmental factors play a crucial role in its aetiopathogenesis. GDM has been linked to both macroscopic and molecular alterations in placental tissues that affect placental physiology. This review summarizes the role of the placenta in the development of GDM from a molecular perspective, including hormonal and pro-inflammatory changes. Inflammation and hormonal imbalance, the characteristics dominating the GDM microenvironment, are responsible for placental changes in size and vascularity, leading to dysregulation in maternal and foetal circulations and to complications in the newborn. In conclusion, since the hormonal mechanisms operating in GDM have not been fully elucidated, more research should be done to improve the quality of life of patients with GDM and their future children.

Keywords: Foetus; gestational diabetes; insulin resistance; low-grade inflammation; obesity; placenta; quality of life.

Figure 1:. Physiological changes in macromolecule metabolism during pregnancy

Figure 2:. Different diagnostic criteria for gestational diabetes mellitus and recommending associations

Figure 3:. The macrovascular and microvascular alterations of the placenta occur due to maternal hyperglycaemia and compensatory hyperinsulinaemia, which lead to foetal hyperglycaemia

Figure 4:. Physiopathology of foetal macrosomia

Figure 5:. Decrease in the oxidative capacity of skeletal muscle