Chow Rebecca P, Zhao Jiawu, Li Yanchun, Curtis Tim M, Lyons Timothy J, Yu Jeremy Y
Division of Endocrinology, Diabetes and Metabolic Diseases, Department of Medicine, Medical University of South Carolina, Charleston, SC, USA; Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Northern Ireland, UK.
Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Northern Ireland, UK; Epsom and St Helier University Hospitals NHS Trust, England, UK.
Eur J Pharmacol. 2025 Jan 5;986:177138. doi: 10.1016/j.ejphar.2024.177138. Epub 2024 Nov 17.
Preeclampsia is prevalent in women with diabetes, but the mechanism is unclear. We previously found that oxidized, glycated lipoproteins robustly upregulated soluble fms-like tyrosine kinase-1 (sFlt1), a key mediator of preeclampsia. Here, we determined the role of protein kinase C (PKC) and its subtypes in sFlt1 regulation in placental trophoblasts, and whether this mechanism might mediate the effect of modified lipoproteins.
Cultured human HTR8/SVneo and BeWo trophoblasts were treated with the PKC activator phorbol-12-myristate-13-acetate (PMA) for 24h, ± PKC inhibitors GF109203X (general), Ro31-8220 (PKCα-selective), LY333531 (PKCβ-selective) and rottlerin (PKCδ-selective). The effect of 'heavily oxidized, glycated' low-density lipoproteins (HOG-LDL) vs. native LDL (N-LDL), ± high glucose (30 mM), was evaluated in HTR8/SVneo cells. sFlt1 secretion (ELISA), mRNA expression (RT-qPCR), and cellular PKC activity were measured.
PMA stimulated robust sFlt1 release and mRNA expression in both cell lines; these effects were inhibited by GF109203X, Ro31-8220 and LY333531 in a concentration-dependent manner. Rottlerin inhibited sFlt1 in BeWo, but modestly enhanced it in HTR8/SVneo cells. HOG-LDL enhanced PKC activity vs. N-LDL in HTR8/SVneo cells. Also, HOG-LDL, but not high glucose, significantly increased sFlt1 secretion and mRNA expression; this response was inhibited by GF109203X, Ro31-8220 and LY333531 at concentrations comparable to those that blocked PMA induction of sFlt1.
Modified lipoproteins upregulate sFlt1 in trophoblasts via a PKC-mediated mechanism, involving at least α and β isoforms. The data suggest potential therapeutic targets to reduce the risk of preeclampsia in women with diabetes.
子痫前期在糖尿病女性中很常见，但其机制尚不清楚。我们之前发现，氧化糖化脂蛋白可显著上调子痫前期的关键介质可溶性fms样酪氨酸激酶-1（sFlt1）。在此，我们确定了蛋白激酶C（PKC）及其亚型在胎盘滋养层细胞中sFlt1调节中的作用，以及该机制是否可能介导修饰脂蛋白的作用。
用PKC激活剂佛波醇-12-肉豆蔻酸酯-13-乙酸酯（PMA）处理培养的人HTR8/SVneo和BeWo滋养层细胞24小时，同时或不同时添加PKC抑制剂GF109203X（通用型）、Ro31-8220（PKCα选择性）、LY333531（PKCβ选择性）和rottlerin（PKCδ选择性）。在HTR8/SVneo细胞中评估“高度氧化糖化”低密度脂蛋白（HOG-LDL）与天然低密度脂蛋白（N-LDL），同时或不同时添加高糖（30 mM）的作用。检测sFlt1分泌（ELISA法）、mRNA表达（RT-qPCR法）和细胞PKC活性。
PMA刺激两种细胞系中sFlt1的大量释放和mRNA表达；这些作用被GF109203X、Ro31-8220和LY333531以浓度依赖性方式抑制。Rottlerin在BeWo细胞中抑制sFlt1，但在HTR8/SVneo细胞中适度增强sFlt1。与N-LDL相比，HOG-LDL增强了HTR8/SVneo细胞中的PKC活性。此外，HOG-LDL而非高糖显著增加sFlt1分泌和mRNA表达；GF109203X、Ro31-8220和LY333531在与阻断PMA诱导sFlt1的浓度相当的情况下抑制了这种反应。
修饰脂蛋白通过PKC介导的机制上调滋养层细胞中的sFlt1，该机制至少涉及α和β亚型。这些数据提示了降低糖尿病女性子痫前期风险的潜在治疗靶点。
