Khusid Johnathan A, Vasquez Alex, Sadiq Areeba S, Stockert Jennifer A, Gallante Blair, Yaghoubian Alan, Shimonov Roman, Stock Aryeh, Atallah William, Kyprianou Natasha, Yang Wei, Gupta Mantu
Icahn School of Medicine at Mount Sinai New York, NY, USA.
Cedars-Sinai Medical Center Los Angeles, CA, USA.
Am J Clin Exp Urol. 2023 Jun 15;11(3):265-274. eCollection 2023.
Kidney stone matrix proteins may help explain cellular mechanisms of stone genesis. However, most existing proteomic studies have focused on calcium oxalate stones. Here, we present a comparative proteomic analysis of different kidney stone types.
Proteins were extracted from the stones of patients undergoing percutaneous nephrolithotomy (PCNL). Approximately 20 μg of protein was digested into tryptic peptides using filter aided sample preparation, followed by liquid chromatography tandem-mass-spectrometry using an EASY-nLC 1200 and Orbitrap Fusion Lumos mass spectrometer. A standard false discovery rate cutoff of 1% was used for protein identification. Stone analysis was used to organize stone samples into similar groups. We selected the top 5% of proteins based on total ion intensities and used DAVID and Ingenuity Pathway Analysis to identify and compare significantly enriched gene ontologies and pathways between groups.
Six specimens were included and organized into the following four groups: 1) mixed uric acid (UA) and calcium-based, 2) pure UA, 3) pure ammonium acid urate (AAU), and 4) pure calcium-based. We identified 2,426 unique proteins (1,310-1,699 per sample), with 11-16 significantly enriched KEGG pathways identified per group and compared via heatmap. Based on number of unique proteins identified, this is the deepest proteomic study of kidney stones to date and the first such study of an AAU stone.
The results indicate that mixed UA and calcium-based kidney stones are more similar to pure UA stones than pure calcium-based stones. AAU stones appear more similar to pure calcium-based stones than UA containing stones and may be related to parasitic infections. Further research with larger cohorts and histopathologic correlation is warranted.
肾结石基质蛋白可能有助于解释结石形成的细胞机制。然而，大多数现有的蛋白质组学研究都集中在草酸钙结石上。在此，我们展示了对不同类型肾结石的比较蛋白质组学分析。
从接受经皮肾镜取石术（PCNL）的患者的结石中提取蛋白质。使用滤膜辅助样品制备将约20μg蛋白质消化成胰蛋白酶肽段，随后使用EASY-nLC 1200和Orbitrap Fusion Lumos质谱仪进行液相色谱串联质谱分析。蛋白质鉴定使用1%的标准错误发现率截断值。通过结石分析将结石样本分组。我们根据总离子强度选择前5%的蛋白质，并使用DAVID和 Ingenuity Pathway Analysis来识别和比较组间显著富集的基因本体和通路。
纳入六个标本并分为以下四组：1）尿酸（UA）和钙混合型，2）纯UA型，3）纯尿酸铵（AAU）型，4）纯钙型。我们鉴定出2426种独特蛋白质（每个样本1310 - 1699种），每组鉴定出11 - 16条显著富集的KEGG通路，并通过热图进行比较。基于鉴定出的独特蛋白质数量，这是迄今为止对肾结石最深层次的蛋白质组学研究，也是对AAU结石的首次此类研究。
结果表明，尿酸和钙混合型肾结石与纯尿酸结石比与纯钙结石更相似。AAU结石似乎比含尿酸结石更类似于纯钙结石，并且可能与寄生虫感染有关。有必要进行更大样本量队列及组织病理学相关性的进一步研究。
