Department of Physiology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands.
Department of Human Genetics, Leiden University Medical Center, Leiden, the Netherlands.
FASEB J. 2020 May;34(5):6382-6398. doi: 10.1096/fj.201902901R. Epub 2020 Mar 11.
Tubular ATP release is regulated by mechanosensation of fluid shear stress (FSS). Polycystin-1/polycystin-2 (PC1/PC2) functions as a mechanosensory complex in the kidney. Extracellular ATP is implicated in polycystic kidney disease (PKD), where PC1/PC2 is dysfunctional. This study aims to provide new insights into the ATP signaling under physiological conditions and PKD. Microfluidics, pharmacologic inhibition, and loss-of-function approaches were combined to assess the ATP release in mouse distal convoluted tubule 15 (mDCT15) cells. Kidney-specific Pkd1 knockout mice (iKsp-Pkd1 ) and zebrafish pkd2 morphants (pkd2-MO) were as models for PKD. FSS-exposed mDCT15 cells displayed increased ATP release. Pannexin-1 inhibition and knockout decreased FSS-modulated ATP release. In iKsp-Pkd1 mice, elevated renal pannexin-1 mRNA expression and urinary ATP were observed. In Pkd1 mDCT15 cells, elevated ATP release was observed upon the FSS mechanosensation. In these cells, increased pannexin-1 mRNA expression was observed. Importantly, pannexin-1 inhibition in pkd2-MO decreased the renal cyst growth. Our results demonstrate that pannexin-1 channels mediate ATP release into the tubular lumen due to pro-urinary flow. We present pannexin-1 as novel therapeutic target to prevent the renal cyst growth in PKD.
管状 ATP 的释放受流体切应力（FSS）机械感觉的调节。多囊蛋白-1/多囊蛋白-2（PC1/PC2）在肾脏中作为机械感受器复合物发挥作用。细胞外 ATP 与多囊肾病（PKD）有关，PC1/PC2 功能失调。本研究旨在为生理条件下和 PKD 中的 ATP 信号提供新的见解。微流控、药物抑制和功能丧失方法相结合，以评估小鼠远曲小管 15（mDCT15）细胞中的 ATP 释放。肾脏特异性 Pkd1 敲除小鼠（iKsp-Pkd1）和斑马鱼 pkd2 嵌合体（pkd2-MO）被用作 PKD 的模型。暴露于 FSS 的 mDCT15 细胞显示出增加的 ATP 释放。缝隙连接蛋白-1 抑制和敲除减少了 FSS 调节的 ATP 释放。在 iKsp-Pkd1 小鼠中，观察到肾脏缝隙连接蛋白-1 mRNA 表达和尿 ATP 升高。在 Pkd1 mDCT15 细胞中，观察到 FSS 机械感觉后 ATP 释放增加。在这些细胞中，观察到缝隙连接蛋白-1 mRNA 表达增加。重要的是，pkd2-MO 中的缝隙连接蛋白-1 抑制可减少肾脏囊肿生长。我们的结果表明，由于促尿流，缝隙连接蛋白-1 通道介导 ATP 释放到管状腔中。我们提出缝隙连接蛋白-1 作为一种新的治疗靶点，以防止 PKD 中的肾脏囊肿生长。
