Department of Animal Science, College of Veterinary Medicine and Biosciences, Texas A&M University, College Station, Texas;
Department of Poultry Science, College of Agriculture and Life Sciences, Texas A&M University, College Station, Texas; and.
Am J Physiol Regul Integr Comp Physiol. 2014 Jun 15;306(12):R918-24. doi: 10.1152/ajpregu.00499.2013. Epub 2014 Apr 9.
Marinobufagenin (MBG) is a cardiotonic steroid that increases in the circulation in preeclampsia. Preeclampsia and eclampsia are associated with cerebral edema. Therefore, we examined the effects of MBG on human brain microvascular endothelial cells (HBMEC) in vitro. MBG enhanced the permeability of HBMEC monolayers at 1-, 10-, and 100-nM doses, but had no effect at 0.1 nM. Agilent Human Gene Expression microarrays were utilized in these studies. MBG treatment (10 nM for 12 h) downregulated concentrations of the soluble VEGFR transcript sFLT by 59% but did not alter those of FLTv3 mRNA (determined by quantitative PCR). When treated and control HBMEC transcriptomes were interrogated on microarrays, 1,069 genes appeared to be regulated by MBG. Quantitative RT-PCR confirmed that MBG treatment upregulated ENKUR mRNA concentrations by 57%. Its protein product interacts with calmodulin and calcium channel proteins. MBG treatment downregulated several genes whose protein products are involved in cell adhesion (ITGA2B, FERMT1, CLDN16, and TMEM207) and cell signaling (GRIN2C, SLC8A1, and ESR1). The level of downregulation ranged from 22 to 66%. Altogether, MBG actively enhanced the permeability of HBMEC monolayers while downregulating genes involved in adhesion. MBG treatment had variable effects on ENKUR, GRIN2C, and SLC8A1 genes, all associated with calcium transport. These studies provide the basis for future investigations of MBG actions in normal physiology and disease.
马林巴因（MBG）是一种强心甾类化合物，在子痫前期会在循环中增加。子痫前期和子痫与脑水肿有关。因此，我们在体外研究了 MBG 对人脑血管内皮细胞（HBMEC）的作用。MBG 在 1、10 和 100 nM 剂量下增强了 HBMEC 单层的通透性，但在 0.1 nM 时没有作用。这些研究使用了安捷伦人类基因表达微阵列。MBG 处理（10 nM 处理 12 h）使可溶性 VEGFR 转录物 sFLT 的浓度降低了 59%，但不改变 FLTv3 mRNA 的浓度（通过定量 PCR 确定）。当处理和对照 HBMEC 转录组在微阵列上进行检测时，有 1069 个基因似乎受到 MBG 的调节。定量 RT-PCR 证实 MBG 处理使 ENKUR mRNA 浓度增加了 57%。其蛋白产物与钙调蛋白和钙通道蛋白相互作用。MBG 处理下调了几个基因的表达，这些基因的蛋白产物参与细胞黏附（ITGA2B、FERMT1、CLDN16 和 TMEM207）和细胞信号转导（GRIN2C、SLC8A1 和 ESR1）。下调幅度从 22%到 66%不等。总之，MBG 积极增强了 HBMEC 单层的通透性，同时下调了参与黏附的基因。MBG 处理对 ENKUR、GRIN2C 和 SLC8A1 基因的作用不同，这些基因都与钙转运有关。这些研究为 MBG 在正常生理和疾病中的作用的进一步研究提供了基础。
