Kim Mi Gyeong, Lee Yun Jung, Choi Eun Sik, Yoon Jung Joo, Han Byung Hyuk, Kang Dae Gill, Lee Ho Sub
Department of Oriental Medicine and Professional Graduate School of Oriental Medicine, Wonkwang University, Iksan, Jeonbuk 540‑749, Republic of Korea.
Mol Med Rep. 2017 May;15(5):2665-2672. doi: 10.3892/mmr.2017.6296. Epub 2017 Mar 7.
The kidneys have a key role in the homeostasis of water excretion and reabsorption. Water channels, particularly aquaporin-2 (AQP2), are important proteins in water homeostasis in the body through the short‑term and long-term regulation of water permeability. Wiryeongtang (WRT) is a well-known traditional oriental medicine, which is used for the treatment of chronic edema and dysuresia. The aim of the present study was to evaluate the inhibitory effect of WRT on the hypertonicity-induced expression of AQP2 in the inner medullary collecting duct cell line (IMCD‑3). Western blotting, reverse transcription‑polymerase chain reaction and immunofluorescence analysis were performed to determine the effect of WRT under hypertonic stress. WRT attenuated the 175 mM NaCl hypertonic stress‑induced increases in protein and mRNA levels of AQP2 and apical membrane insertion in a concentration‑dependent manner. However, no differences were observed in the levels of AQP1, AQP3 or AQP4 between the hypertonic stress and WRT groups. WRT attenuated the hypertonicity-induced phosphorylation of glucocorticoid-inducible protein kinase 1. In addition, the mRNA expression of tonicity‑responsive enhancer binding protein was attenuated by WRT under hypertonic stress. Pretreatment with WRT also decreased the hypertonic stress‑induced expression of AQP2, as with KT5720, a protein kinase A inhibitor. These results provided evidence of the beneficial effect of the traditional formula WRT in regulating water balance in hypertonic stress of the renal collecting ducts.
肾脏在水排泄和重吸收的体内平衡中起关键作用。水通道，特别是水通道蛋白2（AQP2），通过对水通透性的短期和长期调节，是体内水稳态中的重要蛋白质。五苓汤（WRT）是一种著名的传统东方医学方剂，用于治疗慢性水肿和排尿困难。本研究的目的是评估WRT对高渗诱导的髓质内集合管细胞系（IMCD-3）中AQP2表达的抑制作用。进行蛋白质印迹、逆转录-聚合酶链反应和免疫荧光分析以确定在高渗应激下WRT的作用。WRT以浓度依赖性方式减弱了175 mM NaCl高渗应激诱导的AQP2蛋白和mRNA水平的增加以及顶端膜插入。然而，在高渗应激组和WRT组之间，未观察到AQP1、AQP3或AQP4水平的差异。WRT减弱了高渗诱导的糖皮质激素诱导蛋白激酶1的磷酸化。此外，在高渗应激下，WRT减弱了渗透压反应增强子结合蛋白的mRNA表达。与蛋白激酶A抑制剂KT5720一样，WRT预处理也降低了高渗应激诱导的AQP2表达。这些结果提供了传统方剂WRT在调节肾集合管高渗应激中的水平衡方面具有有益作用的证据。
