Department of Emergency Medicine, People's Republic of China; Emergency Medicine and Difficult Diseases Institute, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, People's Republic of China.
Department of Ophthalmology, People's Republic of China.
EBioMedicine. 2022 Feb;76:103859. doi: 10.1016/j.ebiom.2022.103859. Epub 2022 Feb 4.
we demonstrated that disulfide-bond A oxidoreductase-like protein (DsbA-L) was involved in the progression of renal fibrosis. However, the precise function of DsbA-L in acute kidney injury (AKI), and the mechanisms involved, have yet to be elucidated.
We illustrate the DsbA-L interacted with VDAC1 by co-IP (co-immunoprecipitation) in vitro and vivo, and found the interaction parts of them by mutation experiment. The above findings were verified by co-localization of them. In addition, we constructed the two model of PT-DsbA-L and VDAC1 KO mice to verify the function of DsbA-L and VDAC1 in models of VAN, CLP and I/R-induced AKI.
The PT-DsbA-L-KO mice showed amelioration of I/R, VAN-, and CLP-induced AKI progression via the downregulation of VDAC1. Finally, we confirmed these changes in signal molecules by examining in HK-2 cells and kidney biopsies taken from patients with ischemic or acute interstitial nephritis (AIN)-induced AKI. Mechanistically, DsbA-L interacted with amino acids 9-13 and 22-27 of VDAC1 in the mitochondria of BUMPT cells to induce renal cell apoptosis and mitochondrial injury.
This work suggested that DsbA-L, located in the proximal tubular cells, drives the progression of AKI, by directly upregulating the levels of VDAC1.Running Title: The role of DsbA-L in AKI FUNDING: National Natural Science Foundation of China, a grant from Key Project of Hunan provincial science and technology innovation, Department of Science and Technology of Hunan Province project of International Cooperation and Exchanges, Changsha Science and Technology Bureau project, Natural Science Foundation of Hunan Province, Fundamental Research Funds for the Central Universities of Central South University, Hunan Provincial Innovation Foundation For Postgraduate China Hunan Provincial Science and Technology Department.
我们证明了二硫键 A 氧化还原酶样蛋白（DsbA-L）参与了肾纤维化的进展。然而，DsbA-L 在急性肾损伤（AKI）中的精确功能及其涉及的机制尚未阐明。
我们通过体外和体内的 co-IP（共免疫沉淀）实验表明 DsbA-L 与 VDAC1 相互作用，并通过突变实验找到了它们相互作用的部位。通过共定位实验验证了上述发现。此外，我们构建了 PT-DsbA-L 和 VDAC1 KO 两种模型小鼠，以验证 DsbA-L 和 VDAC1 在 VAN、CLP 和 I/R 诱导的 AKI 模型中的功能。
PT-DsbA-L-KO 小鼠通过下调 VDAC1 改善了 I/R、VAN 和 CLP 诱导的 AKI 进展。最后，我们通过检查 HK-2 细胞和缺血或急性间质性肾炎（AIN）诱导的 AKI 患者肾活检中的信号分子证实了这些变化。从机制上讲，DsbA-L 在 BUMPT 细胞的线粒体中与 VDAC1 的氨基酸 9-13 和 22-27 相互作用，诱导肾小管细胞凋亡和线粒体损伤。
这项工作表明，位于近端肾小管细胞中的 DsbA-L 通过直接上调 VDAC1 的水平，推动 AKI 的进展。
