Search

Pregnancy outcome relies on the maintenance of immune and metabolic homeostasis at the maternal fetal interface. Maternal and perinatal morbidity and mortality is associated with impaired placental development. Multiple regulatory effects of the endogenous-produced vasoactive intestinal peptide (VIP) on vascular, metabolic and immune functions at the maternal-fetal interface have been reported. Here we studied the involvement of the two primary high affinity receptors for VIP (VPAC1 and VPAC2) on maternal immune response, placental homeostasis and pregnancy outcome. Targeted disruption of each receptor gene led to altered placental structure, vascular and trophoblast functional markers and shaped the functional profiles of macrophages and neutrophils towards a proinflammatory state. Several changes in pregnant mice were receptor specific: ROS production elicited by VIP on neutrophils was selectively dependent on the presence of VPAC1 whereas apoptosis rate was associated with the VPAC2 deletion. In peritoneal macrophages from pregnant mice, levels of MHC-II, TLR2, and IL-10 were selectively altered in VPAC2 receptor-deficient mice, whereas IL-6 gene expression was reduced only in mice lacking VPAC1 receptors. Additionally, MMP9 mRNA in isolated TGCs was reduced in VPAC2 receptor deleted mice, while the percentage of IL-12 cells in post-phagocytosis macrophage cultures was selectively reduced in VPAC2 receptor deficient mice. The results indicate that manipulation of VPAC1 and VPAC2 receptor affects immune, vascular and metabolic environment at the maternal fetal interface. These mouse models offer new approaches to study pregnancy complications adding new perspectives to the development of VPAC receptor-selective drugs.

Immunometabolism research is uncovering the relationship between metabolic features and immune cell functions in physiological and pathological conditions. Normal pregnancy entails a fine immune and metabolic regulation of the maternal-fetal interaction to assist the energetic demands of the fetus with immune homeostasis maintenance. Here, we determined the immunometabolic status of monocytes of pregnant women compared with nonpregnant controls and its impact on monocyte anti-inflammatory functions such as efferocytosis. Monocytes from pregnant women (16-20 wk) and nonpregnant age-matched controls were studied. Single cell-based metabolic assays using freshly isolated monocytes from both groups were carried out in parallel with functional assays ex vivo to evaluate monocyte efferocytic capacity. On the other hand, various in vitro metabolic assays with human monocytes or monocyte-derived macrophages were designed to explore the effect of trophoblast cells in the profiles observed. We found that pregnancy alters monocyte metabolism and function. An increased glucose dependency and enhanced efferocytosis were detected in monocytes from pregnant women at resting states, compared with nonpregnant controls. Furthermore, monocytes display a reduced glycolytic response when stimulated with lipopolysaccharide (LPS). The metabolic profiling of monocytes at this stage of pregnancy was comparable with the immunometabolic phenotypes of human monocytes treated in vitro with human first trimester trophoblast cell conditioned media. These findings suggest that immunometabolic mechanisms are involved in the functional shaping of monocytes during pregnancy with a contribution of trophoblast cells. Results provide new clues for future hypotheses regarding pregnancies complicated by metabolic disorders. [ABSTRACT FROM AUTHOR]

Problem: Decidualized cells display an active role during embryo implantation sensing blastocyst quality, allowing the implantation of normal developed blastocysts and preventing the invasion of impaired developed ones. Here, we characterized the immune microenvironment generated by decidualized cells in response to soluble factors secreted by blastocysts that shape the receptive milieu. Method of Study: We used an in vitro model of decidualization based on the Human Endometrial Stromal Cells line (HESC) differentiated with medroxiprogesterone and dibutyryl‐cAMP, then treated with human blastocysts‐conditioned media (BCM) classified according to their quality. Results: Decidualized cells treated with BCM from impaired developed blastocysts increased IL‐1β production. Next, we evaluated the ability of decidualized cells to modulate other mediators associated with menstruation as chemokines. Decidualized cells responded to stimulation with BCM from impaired developed blastocysts increasing CXCL12 expression and CXCL8 secretion. The modulation of these markers was associated with the recruitment and activation of neutrophils, while regulatory T cells recruitment was restrained. These changes were not observed in the presence of BCM from normal developed blastocysts. Conclusion: Soluble factors released by impaired developed blastocysts induce an exacerbated inflammatory response associated with neutrophils recruitment and activation, providing new clues to understand the molecular basis of the embryo‐endometrial dialogue. [ABSTRACT FROM AUTHOR]

ABSTRACT Immunometabolism is an emerging growing field that focuses on the role of cellular metabolism in the regulation of immune cell function and fate. Thus, proliferation, differentiation, activation, and function of immune cell populations are modulated by reprogramming their fueling and metabolic pathways. Pregnancy entails a fine immune and metabolic regulation of the maternal−fetal interaction to assist the energetic demands of the fetus where trophoblast cells have a central role. Maternal neutrophil functional shaping by trophoblast cells has been proposed though their metabolic conditioning during pregnancy has not been studied yet. Here, we explored the effects of trophoblast‐derived factors on the metabolic rewiring of neutrophils from nonpregnant women and its impact on central functions like reactive oxygen species (ROS) production, neutrophil extracellular trap (NET) release, and migration. In parallel, the immunometabolic status and function of neutrophils isolated from pregnant women (16−20 weeks) was compared with nonpregnant age‐matched control samples. Trophoblast‐derived factors induced glucose uptake and lipid droplet accumulation without activating ROS production or NET release. Conditioned media from trophoblast cells also inhibited PMA‐induced NETosis partly by impairing glucose uptake in neutrophils. In turn, neutrophils from pregnant women had increased basal ROS production, lipid accumulation, and glucose uptake compared to neutrophils from nonpregnant women, accompanied by a higher release of PMA‐induced NETs. Interestingly, PMA‐induced NETs was blocked by a fatty acid oxidation inhibitor in neutrophils from pregnant women indicating the contribution of fatty acid metabolism to neutrophil activity during pregnancy. Results are consistent with immunometabolic mechanisms underlying the functional shaping of neutrophils during pregnancy and point out the contribution of trophoblast‐derived factors to their metabolic profiling. These findings provide novel immunometabolic clues to understand immune homeostasis maintenance during pregnancy and raise the clinical potential of monitoring neutrophil metabolism during normal and complicated pregnancies. [ABSTRACT FROM AUTHOR]

The placenta has an extraordinary metabolic rate with high oxygen consumption. Extravillous cytotrophoblast cells (EVT) metabolism and function are critical to sustain their invasive phenotype supporting fetal development. Deficient EVT function underlies pregnancy complications as preeclampsia (PE) and fetal growth restriction (FGR). The vasoactive intestinal peptide (VIP) promotes human cytotrophoblast cell migration and invasion through mTOR signaling pathways suggesting its crucial role during placentation. Here we explored fatty acid uptake as well as lipid and glucose metabolism in human-derived cytotrophoblast cell function upon VIP stimulation. We found that VIP induced long chain fatty acid (LCFAs) uptake along with the expression of FATP2 transporter, CPT1 fatty acid oxidation (FAO)-rate limiting step importer, and lipid droplet accumulation. VIP induced the expression of glucose 6-P-dehydrogenase, a rate-limiting enzyme of the pentose phosphate pathway (PPP) and pyruvate dehydrogenase complex enzyme DLAT E2, without altering lactate secretion. This metabolic rewiring of trophoblast cells induced by VIP takes place without compromising mitochondrial function or reactive oxygen species (ROS) production. Moreover, cytotrophoblast cell migration induced by VIP required the three glycolysis, oxidative phosphorylation (OXPHOS) and FAO pathways. Our results provide evidence supporting VIP as a metabolic regulatory peptide in cytotrophoblast cells sustaining proper placentation and fetal growth., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)