Department of Physiology and Pharmacology, Western University, London, Ontario, Canada.
Department of Obstetrics and Gynaecology, Western University, London, Ontario, Canada.
Reproduction. 2021 Jan;161(1):73-88. doi: 10.1530/REP-19-0433.
Placental villous trophoblast mitochondrial respiratory function is critical for a successful pregnancy and environmental influences such as maternal obesity have been associated with respiratory impairment at term. More recently, a gestational high fat diet independent of maternal body composition, has been highlighted as a potential independent regulator of placental mitochondrial metabolism. The current study aimed to characterize the direct impact of a prolonged and isolated exposure to the dietary fatty acids Palmitate (PA) and Oleate (OA) upon placental cell mitochondrial respiratory function. BeWo cytotrophoblast (CT) and syncytiotrophoblast (SCT) cells were treated for 72 h with 100 µM PA, OA or PA+OA (P/O). Live-cell metabolic function was analyzed via the Seahorse XF Mito and Glycolysis Stress tests. Immunoblots and spectrophotometric activity assays were utilized to examine the protein expression and function of electron transport chain (ETC) complexes and key mitochondrial regulatory enzymes. Syncytialization of BeWo cells resulted reduced respiratory activity in conjunction with altered complex I and II activity and decreased pyruvate dehydrogenase (PDH) protein expression and activity. PA and P/O treatments were associated with increased basal and maximal respiratory activities in BeWo CT cells without alterations in protein expression or activity of individual ETC complexes and mitochondrial substrate regulators. The metabolic suppression in BeWo SCTs was consistent with that previously observed in primary human trophoblast cell cultures, while the observed increases in respiratory activity in PA-treated BeWo CTs may be indicative of an early timepoint of specific dietary saturated fat-mediated placental cell mitochondrial dysfunction.
胎盘绒毛滋养细胞线粒体呼吸功能对于成功妊娠至关重要,环境影响,如母体肥胖,与足月时的呼吸功能障碍有关。最近,一种与母体身体成分无关的妊娠期高脂肪饮食,已被强调为胎盘线粒体代谢的潜在独立调节剂。本研究旨在描述长时间和单独暴露于膳食脂肪酸棕榈酸(PA)和油酸(OA)对胎盘细胞线粒体呼吸功能的直接影响。BeWo 滋养细胞(CT)和合体滋养细胞(SCT)分别用 100μM PA、OA 或 PA+OA(P/O)处理 72 小时。通过 Seahorse XF Mito 和糖酵解应激试验分析活细胞代谢功能。免疫印迹和分光光度法活性测定用于检测电子传递链(ETC)复合物和关键线粒体调节酶的蛋白表达和功能。BeWo 细胞的合胞体化与复合物 I 和 II 活性降低以及丙酮酸脱氢酶(PDH)蛋白表达和活性降低有关,导致呼吸活性降低。PA 和 P/O 处理与 BeWo CT 细胞基础和最大呼吸活性增加有关,而单个 ETC 复合物和线粒体底物调节剂的蛋白表达或活性没有改变。BeWo SCTs 的代谢抑制与先前在原代人滋养层细胞培养物中观察到的一致,而在 PA 处理的 BeWo CTs 中观察到的呼吸活性增加可能表明特定膳食饱和脂肪介导的胎盘细胞线粒体功能障碍的早期时间点。