Label-free Quantitative Urinary Proteomics Identifies the Arginase Pathway as a New Player in Congenital Obstructive Nephropathy

Abstract

Obstructive nephropathy is a frequently encountered situation in newborns. In previous studies, the urinary peptidome has been analyzed for the identification of clinically useful biomarkers of obstructive nephropathy. However, the urinary proteome has not been explored yet and should allow additional insight into the pathophysiology of the disease. We have analyzed the urinary proteome of newborns (n ‫؍‬ 5/group) with obstructive nephropathy using label free quantitative nanoLC-MS/MS allowing the identification and quantification of 970 urinary proteins. We next focused on proteins exclusively regulated in severe obstructive nephropathy and identified Arginase 1 as a potential candidate molecule involved in the development of obstructive nephropathy, located at the crossroad of pro-and antifibrotic pathways. The reduced urinary abundance of Arginase 1 in obstructive nephropathy was verified in independent clinical samples using both Western blot and MRM analysis. These data were confirmed in situ in kidneys obtained from a mouse obstructive nephropathy model. In addition, we also observed increased expression of Arginase 2 and increased total arginase activity in obstructed mouse kidneys. mRNA expression analysis of the related arginase pathways indicated that the pro-fibrotic arginase-related pathway is activated during obstructive nephropathy. Taken

Investigation of urine proteome of preterm newborns with respiratory pathologies

“…Non-invasive MS based methods for monitoring the status of children with ELBW and VLBW are based on the analysis of easily accessible biomaterials such as buccal scrapings [5], exhaled breath condensate [6], and urine [7][8][9][10]. Biomarkers in the urine samples of infants are widely used for predicting such pathologies as obstructive nephropathy [11,12], necrotizing enterocolitis [13], and for monitoring maturation and development of the urinary system [7]. The majority of throughput urine proteome studies are focused on the adult population (control and disease) [14][15][16][17].…”

Assay of L-Arginine in rat blood by enzymatic method

“…Арг -глюкогенна напівзамінна амінокислота, важливий метаболіт циклу сечовини [10,11]. Арг бере участь у численних біохімічних процесах, що мають місце в організмі ссавців, включаючи деток-сикацію аміаку, секрецію гормонів і т. ін.…”

“…Зрозуміло, що при та-кому лікуванні потрібно ретельно контролювати рі-вень Арг у крові та сечі. Аналогічний моніторинг є необхідним при ензимотерапії деяких видів раку (ме-ланоми, гепатокарциноми і пухлин підшлункової залози) аргіназою І печінки людини [9][10][11].…”

“…Як субстрати NO-синтази, Арг та його сполуки можуть бути важливими біомаркерами у клінічній діагностиці не тільки серцево-судинних [12], але і нейродегенеративних, легеневих [11], ауто-імунних захворювань [2], сепсису, гіпераргінінемії (аргінінемія) і гіперамоніємія (амоніємія) [2,[10][11][12].…”

Quantitative body fluid proteomics in medicine — A focus on minimal invasiveness

“…Under normal conditions, urine contains proteins originating from the blood and kidneys [134][135][136][137][138][139], making urine a good source for analysis of diseases affecting the kidney or the urogenital tract; such as kidney failure resulting from high blood pressure and diabetic nephropathy [140,141], prostate cancer [142,143], polycystic kidney disease [144], kidney chronic allograft dysfunction [145], chronic allograft nephropathy [146], congenital obstructive nephropathy [147], lupus nephritis [148], urolithiasis [149], in addition to urinary, renal and bladder cancer [150][151][152][153][154][155][156][157][158][159][160][161]. Besides urogenital and kidney dysfunctions, urinary proteomics has a great potential in biomarker studies of coronary artery atherosclerosis [162,163], obstructive sleep apnea [164], ovarian cancer [165], breast cancer [166] and sepsis [167,168].…”