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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, OBJECTIVE, METHODS, RESULTS. Meshes: Activin Receptors, Type I, Activins, Adult, Amino Acid Sequence, Apoptosis, Case-Control Studies, Cells, Cultured, Female, Humans, Matrix Metalloproteinases, Molecular Sequence Data, Placenta, Pre-Eclampsia, Pregnancy, Prospective Studies, Signal Transduction, Trophoblasts.
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Do high levels of activin A detected in preeclamptic placenta induce trophoblast cell apoptosis by promoting nodal signaling? Context: The pregnancy-specific disorder preeclampsia is a major cause of maternal mortality and morbidity. Activin A has been suggested as a potential biomarker of the disease, but whether it plays a role in the pathology of preeclampsia or is just a manifestation of the disease is not fully understood. The objective of the study was to examine the roles of Activin A on placental trophoblast cells under pathological conditions of preeclampsia. Placental and plasma productions of Activin A in healthy pregnant women and preeclamptic patients were compared by using clinical samples obtained from Peking University First Hospital during November 2005 to November 2007. The role of Activin A at pathological doses was investigated in human trophoblast cells. Plasma and placental productions of Activin A were significantly higher in preeclamptic patients when compared with normal pregnant subjects in a Chinese Han population. Treatment of trophoblast cells with high doses of Activin A resulted in a significant increase in cell apoptosis. This effect was blocked not only by silencing Activin A's receptor activin receptor-like kinase 4 but also by knockdown of Nodal's receptor ALK7. Important to note was that Activin A could significantly increase Nodal expression in trophoblast cells, and knockdown of Nodal resulted in evident blockage on Activin A-induced trophoblast cell apoptosis.
assistant
High levels of Activin A observed in preeclamptic placenta may play a role in the pathogenesis of preeclampsia by inducing excessive apoptosis in placenta indirectly through enhancing Nodal expression. Final Decision: yes