Sakamoto Kazuo, Kawanishi Kunio, Kim Jun-Dal, Koizumi Masahiro, Muroi Shin-Ichi, Tabara Saori, Fukamizu Akiyoshi, Matsusaka Taiji, Nagata Michio
Kidney and Vascular Pathology, Institute of Medicine, University of Tsukuba.
Department of Experimental Pathology, Institute of Medicine, University of Tsukuba.
Proc Jpn Acad Ser B Phys Biol Sci. 2025 Jul 29;101(7):431-444. doi: 10.2183/pjab.101.025. Epub 2025 Jun 20.
Renal counterbalance, involving compensatory hypertrophy of the healthy kidney and atrophy of the injured one, remains incompletely understood, particularly at the glomerular level. In this study, we employed NEP25 mice, which selectively express human CD25 in podocytes, enabling precise induction of unilateral podocyte injury through the administration of LMB2, a CD25-targeted immunotoxin. Using a two-kidney, one-nephropathy (2K1N) model, we demonstrated that asymmetric changes in renal blood flow and proteinuria, with histological and transcriptomic analyses uncovering distinct pathological and molecular features between the injured and contralateral healthy kidneys. Notably, an imbalance in intrarenal angiotensin (Ang) II levels was observed, and angiotensin-converting enzyme inhibition ameliorated the glomerular damage and restored perfusion. These findings indicate that local Ang II dysregulation is a key factor in renal counterbalance. Our study provides the first glomerulopathy-based experimental platform to dissect asymmetric renal adaptation, offering fundamental insight into the homeostatic mechanisms of renal function in health and disease.
肾代偿平衡,包括健康肾脏的代偿性肥大和受损肾脏的萎缩,目前仍未被完全理解,尤其是在肾小球水平。在本研究中,我们使用了NEP25小鼠,其在足细胞中选择性表达人CD25,通过给予靶向CD25的免疫毒素LMB2能够精确诱导单侧足细胞损伤。使用双肾单肾病(2K1N)模型,我们证明了肾血流和蛋白尿的不对称变化,组织学和转录组分析揭示了受损肾脏和对侧健康肾脏之间不同的病理和分子特征。值得注意的是,观察到肾内血管紧张素(Ang)II水平失衡,血管紧张素转换酶抑制可改善肾小球损伤并恢复灌注。这些发现表明局部Ang II失调是肾代偿平衡的关键因素。我们的研究提供了首个基于肾小球病的实验平台来剖析不对称肾适应性,为健康和疾病状态下肾功能的稳态机制提供了基本见解。