背景:源自人多能干细胞(HiPSCs)的肾脏类器官在药物筛选中具有巨大的应用,疾病建模,和细胞移植治疗。然而,这些应用是有限的,因为肾脏类器官不能像人类肾脏一样保持完整的形态和功能。肾脏的器官没有很好的分化,因为器官的核心缺乏氧气,营养,和脉管系统,这创造了必要的利基。低氧诱导因子-1α(HIF-1α)是低氧环境下血管形成和细胞存活的关键调节因子。在这方面,关于HIF-1α在肾脏类器官中的作用知之甚少。本研究试图探讨HIF-1α在肾脏器官血管化和相关疾病建模中的作用。
方法:对于血管化研究,肾脏的类器官是从人类诱导的多能干细胞中产生的。我们通过质粒转染或处理的DMOG过表达HIF-1α(二甲基氧基烯丙基甘氨酸,HIF-1α稳定和积累的试剂)在肾祖细胞中检测内皮。对于疾病建模研究,我们在缺氧环境下用顺铂治疗肾类器官,用额外的HIF-1α转染。
结果:HIF-1α过表达引起肾脏类器官血管化。在HIF-1α质粒转染和DMOG处理的类器官中,内皮细胞和血管紧张素分析参数增加。这些血管生成过程被VEGFR抑制剂部分阻断,semaxanib或axitinib。HIF-1α通过上调CD31和SOD2来保护顺铂诱导的肾损伤(裂解的半胱天冬酶3)。
结论:我们证明HIF-1α引起了肾脏类器官血管化的过程,并在缺氧环境中保护了顺铂引起的肾脏类器官损伤。
Kidney organoids derived from human pluripotent stem cells (HiPSCs) hold huge applications for drug screening, disease modeling, and cell transplanting therapy. However, these applications are limited since kidney organoid cannot maintain complete morphology and function like human kidney. Kidney organoids are not well differentiated since the core of the organoid lacked oxygen, nutrition, and vasculature, which creates essential niches. Hypoxia-inducible factor-1 α (HIF-1α) serves as a critical regulator in vascularization and cell survival under hypoxia environment. Less is known about the role of HIF-1α in kidney organoids in this regard. This study tried to investigate the effect of HIF-1α in kidney organoid vascularization and related disease modeling.
For the vascularization study, kidney organoids were generated from human induced pluripotent stem cells. We overexpressed HIF-1α via plasmid transfection or treated DMOG (Dimethyloxallyl Glycine, an agent for HIF-1α stabilization and accumulation) in kidney progenitor cells to detect the endothelium. For the disease modeling study, we treated kidney organoid with cisplatin under hypoxia environment, with additional HIF-1α transfection.
HIF-1α overexpression elicited kidney organoid vascularization. The endothelial cells and angiotool analysis parameters were increased in HIF-1α plasmid-transfected and DMOG-treated organoids. These angiogenesis processes were partially blocked by VEGFR inhibitors, semaxanib or axitinib. Cisplatin-induced kidney injury (Cleaved caspase 3) was protected by HIF-1α through the upregulation of CD31 and SOD2.
We demonstrated that HIF-1α elicited the process of kidney organoid vascularization and protected against cisplatin-induced kidney organoid injury in hypoxia environment.