Influência da suplementação de ômega 3 durante a gestação e seu impacto na placenta: revisão integrativa experimental e clínica

Abstract

The placenta is a temporary and multifunctional organ, essential for healthy fetal development, acting as a vital metabolic, endocrine, and immunological interface for the exchange of nutrients, gases, and hormones between the mother and the conceptus. Recognizing its vulnerability to stressors, supplementation with omega 3 polyunsaturated fatty acids (PUFAs) emerges as a nutritional strategy to improve maternal-fetal health and, primarily, placental homeostasis. This thesis investigates the influence of omega 3 fatty acid supplementation during pregnancy and its impact on placental pathophysiology, integrating findings from experimental studies with rodents and clinical trials in humans. The methodology consists of an integrative literature review, based on the framework of Whittemore; Knafl and Kutcher; LeBaron using the PubMed, LILACS, and Cochrane Library databases. The search was guided by the PICO question: Does omega 3 supplementation, compared to the absence of supplementation, promote structural and functional improvements in the placenta? Twenty-four studies were included, of which 16 used animal models and 8 were RCTs. In studies with animal models, omega 3 has consistently demonstrated high efficacy, being associated with the activation of peroxisome proliferator-activated receptor gamma (PPARG), a central mechanism that regulates lipid transport (via FATP4 and CD36) and placental bioenergy. Furthermore, omega 3 has been described as a powerful anti-inflammatory and antioxidant axis, providing pro-resolution mediators (such as resolvins and protectins) and increasing the activity of enzymes such as SOD, GPx, and catalase, essential for maintaining technical integrity and perfusion. In stark contrast, scientific clinical trials in humans have demonstrated evidence of low clinical reliability, marked by high risk of death (RoB2), heterogeneous results, and, critically, failure to confirm that essential molecular targets were achieved in pregnant women, which explains the weakness of the clinical evidence. The study concludes that omega 3 supplementation has the potential to specifically modulate placental biology, as consistently evidenced in experimental models through the optimization of lipid transport and the resolution of inflammation. However, in the clinical trials studied, the current evidence remains inconclusive and does not allow for a universal assertion that supplementation improved placental composition and health. This thesis points to important gaps that need to be investigated so that omega 3 can be used for placental health. The translational divergence reveals that the clinical efficacy of omega 3 depends on overcoming methodological flaws and transitioning to an isolation nutrition paradigm, based on the genetic and metabolic stratification of pregnant women.