Department of Medicine, Division of Nephrology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K.
Department of Pediatrics, Division of Hematology-Oncology, Section of Cardio-Renal Physiology and Medicine, University of Alabama at Birmingham, Birmingham, AL 35233, U.K.
Biosci Rep. 2024 Jul 31;44(7). doi: 10.1042/BSR20240768.
The intrarenal endothelin (ET) system is an established moderator of kidney physiology and mechanistic contributor to the pathophysiology and progression of chronic kidney disease in humans and rodents. The aim of the present study was to characterize ET system by combining single cell RNA sequencing (scRNA-seq) data with immunolocalization in human and rodent kidneys of both sexes. Using publicly available scRNA-seq data, we assessed sex and kidney disease status (human), age and sex (rats), and diurnal expression (mice) on the kidney ET system expression. In normal human biopsies of both sexes and in rodent kidney samples, the endothelin-converting enzyme-1 (ECE1) and ET-1 were prominent in the glomeruli and endothelium. These data agreed with the scRNA-seq data from these three species, with ECE1/Ece1 mRNA enriched in the endothelium. However, the EDN1/Edn1 gene (encodes ET-1) was rarely detected, even though it was immunolocalized within the kidneys, and plasma and urinary ET-1 excretion are easily measured. Within each species, there were some sex-specific differences. For example, in kidney biopsies from living donors, men had a greater glomerular endothelial cell endothelin receptor B (Ednrb) compared with women. In mice, females had greater kidney endothelial cell Ednrb than male mice. As commercially available antibodies did not work in all species, and RNA expression did not always correlate with protein levels, multiple approaches should be considered to maintain required rigor and reproducibility of the pre- and clinical studies evaluating the intrarenal ET system.
肾脏内的内皮素（ET）系统是调节肾脏生理功能的重要机制，也是人类和啮齿动物慢性肾脏病病理生理学和进展的机制性贡献因素。本研究的目的是通过将单细胞 RNA 测序（scRNA-seq）数据与免疫定位相结合，对人类和啮齿动物的肾脏 ET 系统进行特征描述。本研究使用公开的 scRNA-seq 数据，评估了肾脏 ET 系统的表达与性别和肾脏疾病状态（人类）、年龄和性别（大鼠）以及昼夜表达（小鼠）的关系。在正常的男女活检组织和啮齿动物肾脏样本中，内皮素转换酶 1（ECE1）和 ET-1 在肾小球和内皮细胞中表达丰富。这些数据与这三个物种的 scRNA-seq 数据一致，ECE1/Ece1mRNA 在血管内皮细胞中富集。然而，EDN1/Edn1 基因（编码 ET-1）很少被检测到，尽管它在肾脏内被免疫定位，并且血浆和尿液中的 ET-1 排泄很容易测量。在每个物种中，都存在一些性别特异性差异。例如，在活体供体的肾脏活检组织中，男性的肾小球内皮细胞内皮素受体 B（Ednrb）比女性更多。在小鼠中，雌性的肾脏内皮细胞 Ednrb 比雄性更多。由于商业上可获得的抗体在所有物种中都不能正常工作，并且 RNA 表达并不总是与蛋白质水平相关，因此应该考虑多种方法来维持评估肾脏内 ET 系统的临床前和临床研究的严格性和可重复性。
