Expressão de marcadores de macrófagos na decídua de gestantes obesas

Abstract

The placenta is the fundamental organ of pregnancy, responsible for creating the environment in which the exchange of substances between the mother and the fetus takes place, making its physiological regulation critically important. Obesity is a multifactorial disease characterized by the accumulation of adipose tissue throughout various body compartments, contributing to insulin resistance and metabolic changes that disrupt homeostasis. Excess visceral fat during pregnancy increases the risk of gestational diabetes and hypertension, prolonged time to conception, pre-eclampsia, preterm birth, cardiovascular issues in the mother, high birth weight, and elevated BMI in adolescence. Macrophages are cells of the innate immune system that defend against pathogens, assist in tissue remodeling, and present antigens to T lymphocytes. Their activation varies according to the microenvironment, assuming inflammatory (M1) or anti-inflammatory (M2) profiles, reflecting their functional plasticity. Moreover, obesity affects the cellular composition and microenvironment of adipose tissue, in which macrophages increase in number and shift from an M2 (anti-inflammatory) to an M1 (pro-inflammatory) phenotype. A similar shift can be observed in placental cellular composition. Thus, this study investigates how maternal obesity may affect the immune environment of the placenta, particularly in the decidua, the maternal portion of this organ. The research focused on the expression of macrophage marker genes (CD206, CD163, and HLA-DRB1), which indicate M2 (anti-inflammatory) and M1 (pro-inflammatory) profiles. Forty decidual samples from obese and eutrophic pregnant women were compared by analyzing gene expression data through qPCR and correlating the results with the participants’ anthropometric data. The results showed reduced expression of M2 markers in obese women, suggesting a shift in the placental immune profile associated with the chronic inflammatory state of obesity. These findings indicate potential negative impacts on maternal-fetal health and reinforce the need for further research on the effects of obesity during pregnancy.