Anatomie pathologique de l’insuffisance vasculaire utéroplacentaire

Pathogenesis of uteroplacental acute atherosis: An update on current research

Uteroplacental acute atherosis is a type of arterial vascular disease that affects the placenta during pregnancy and predominates in the maternal spiral arteries in the decidua basalis layer of the pregnant uterus. This condition is characterized by fibrin-like necrosis of the blood vessel walls, the accumulation of macrophages containing fat (foam cells), and the infiltration of macrophages around blood vessels. Uteroplacental acute atherosis is rare in normal pregnancy but occurs more frequently in patients with pregnancy complications, including preeclampsia, spontaneous preterm labor, preterm prelabor rupture of membranes, mid-trimester spontaneous abortion, fetal death, and small-for-gestational age. It is believed that the mechanisms underlying the development of uteroplacental acute atherosis are related to the incomplete physiological transformation of spiral arteries, placental inflammation, abnormal lipid metabolism, and oxidative stress. In this review, we describe the pathogenesis of uteroplacental acute atherosis to provide reference guidelines for the future prevention and treatment of uteroplacental acute atherosclerotic disease.

Hypoxia downregulates the angiogenesis in human placenta via Notch1 signaling pathway

Placentation, which is critical for maternal-fetal exchange of nutrients and gases, is a complicated process comprising stepwise vasculogenesis and angiogenesis. Hypoxia caused by impaired trophoblast invasion may cause various angiogenic abnormalities in human placenta. The Notch1 signaling pathway plays an important role in the regulation of angiogenesis. The angiogenesis of human umbilical vein endothelial cells (HUVECs) under normal/hypoxic conditions and the mRNA/protein level of Notch1/Dell4/Jagged1 were investigated in this study. The effects of DAPT/JAG-1 on the migration of HUVECs were also assessed by cell wound healing assay, so as to discover the possible role of notch1 signaling pathway in the angiogenesis of human placenta. The results showed that angiogenic ability of HUVECs was seriously reduced under hypoxic conditions. The mRNA and protein levels of Notch1/Dell4/Jagged1 were decreased in the hypoxic group compared to the control one. In addition, the migration capability of HUVECs was significantly obstructed when treated with DAPT and under hopoxic condition, but promoted when treated with JAG-1. The above results demonstrate that hypoxia downregulates the angiogenesis in human placenta via Notch1 signaling pathway.

Chorangiomatosis: Evaluation of a placental vascular lesion and related clinical effects

BACKGROUND

Chorangiomatosis is a unique placental vascular abnormality that can cause growth retardation and even fetal demise in severe cases. In this study we aim to better understand this lesion and the possible clinical implications.

METHODS AND MATERIALS

In this study 170 placentas were evaluated, both grossly and microscopically. The patients' charts were reviewed and relevant clinical data were extracted. In the histological examination, presence of placental lesions including chorangiomatosis (focal, multifocal and diffuse) and chorangiosis was determined and possible correlation between placental findings and clinical outcomes investigated.

RESULTS

Among the 170 placentas examined, 42 cases of multifocal chorangiomatosis (25.6%), 7 cases with diffuse chorangiomatosis (4.26%), and 56 cases of focal chorangiomatosis (34.1%) were identified. We found that there is a significant correlation between multifocal/diffuse chorangiomatosis and adverse clinical outcomes including lower birth weight and NICU admission.

CONCLUSION

Chorangiomatosis can significantly affect the outcomes of pregnancy and more research is needed to better understand this lesion.