Amity Institute of Biotechnology (AIB), Amity University, Noida, Uttar Pradesh 201301, India.
Amity Institute of Molecular Medicine and Stem Cell Research (AIMMSCR), Amity University, Noida, Uttar Pradesh 201301, India.
Life Sci. 2020 Dec 1;262:118498. doi: 10.1016/j.lfs.2020.118498. Epub 2020 Sep 28.
Increased levels of urinary oxalate also known as hyperoxaluria, increase the likelihood of kidney stone formation through enhanced calcium oxalate (CaOx) crystallization. The management of lithiatic renal pathology requires investigations at the initial macromolecular stages. Hence, the current study was designed to unravel the protein make-up of human kidney stones and its impact on renal cells' altered proteome, induced as the consequence of CaOx injury. CaOx kidney stones were collected from patients; stones were pooled for entire cohort, followed by protein extraction. Immunocytochemistry, RT-PCR and flow-cytometric analysis revealed the promising antilithiatic activity of kidney stone matrix proteins. The iTRAQ analysis of renal cells showed up-regulation of 12 proteins and down-regulation of 41 proteins due to CaOx insult, however, this differential expression was normalized in the presence of kidney stone matrix proteins. Protein network analysis revealed involvement of up-regulated proteins in apoptosis, calcium-binding, inflammatory and stress response pathways. Moreover, seven novel antilithiatic proteins were identified from human kidney stones' matrix: Tenascin-X-isoform2, CCDC-144A, LIM domain kinase-1, Serine/Arginine receptor matrix protein-2, mitochondrial peptide methionine sulfoxide reductase, volume-regulated anion channel subunit-LRRC8A and BMPR2. In silico analysis concluded that these proteins exert antilithiatic potential through crystal binding, thereby inhibiting the crystal-cell interaction, a pre-requisite to initiate inflammatory response. Thus, the outcomes of this study provide insights into the molecular events of CaOx induced renal toxicity and subsequent progression into nephrolithiasis.
尿草酸水平升高，即高草酸尿症，通过增强草酸钙（CaOx）结晶，增加肾结石形成的可能性。结石性肾病病理的管理需要在最初的大分子阶段进行调查。因此，本研究旨在揭示人肾结石的蛋白质组成及其对肾脏细胞蛋白质组改变的影响，这种改变是草酸钙损伤的结果。从患者中收集 CaOx 肾结石；将结石汇集到整个队列中，然后进行蛋白质提取。免疫细胞化学、RT-PCR 和流式细胞分析显示肾结石基质蛋白具有有前途的抗结石活性。肾细胞的 iTRAQ 分析显示，由于 CaOx 损伤，有 12 种蛋白质上调，41 种蛋白质下调，但在存在肾结石基质蛋白的情况下，这种差异表达得到了正常化。蛋白质网络分析显示，上调蛋白参与细胞凋亡、钙结合、炎症和应激反应途径。此外，从人肾结石基质中鉴定出 7 种新的抗结石蛋白：Tenascin-X-异构体 2、CCDC-144A、LIM 结构域激酶-1、丝氨酸/精氨酸受体基质蛋白-2、线粒体肽甲硫氨酸亚砜还原酶、体积调节阴离子通道亚基-LRRC8A 和 BMPR2。计算机分析得出结论，这些蛋白质通过晶体结合发挥抗结石潜力，从而抑制晶体-细胞相互作用，这是引发炎症反应的先决条件。因此，本研究的结果提供了对 CaOx 诱导的肾毒性和随后进展为肾结石的分子事件的深入了解。
