
Identification of urinary proteins potentially associated with diabetic kidney disease
Author(s) -
Ravi Kumar Marikanty,
Malaya Gupta,
Swamy V. Cherukuvada,
Sindhura Kompella,
Aruna K Prayaga,
Shruthi Konda,
Ravindra Varma Polisetty,
Mohammed M. Idris,
Paturi Vishnupriya Rao,
Giriraj Ratan Chandak,
KV Dakshinamurty
Publication year - 2016
Publication title -
indian journal of nephrology/indian journal of nephrology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.317
H-Index - 24
eISSN - 1998-3662
pISSN - 0971-4065
DOI - 10.4103/0971-4065.176144
Subject(s) - diabetic nephropathy , medicine , albuminuria , tamm–horsfall protein , gel electrophoresis , proteome , blood proteins , urine , kidney , biochemistry , endocrinology , chemistry
Diabetic nephropathy (DN) is the most common cause of chronic kidney disease. Although several parameters are used to evaluate renal damage, in many instances, there is no pathological change until damage is already advanced. Mass spectrometry-based proteomics is a novel tool to identify newer diagnostic markers. To identify urinary proteins associated with renal complications in diabetes, we collected urine samples from 10 type 2 diabetes patients each with normoalbuminuria, micro- and macro-albuminuria and compared their urinary proteome with that of 10 healthy individuals. Urinary proteins were concentrated, depleted of albumin and five other abundant plasma proteins and in-gel trypsin digested after prefractionation on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The peptides were analyzed using a nanoflow reverse phase liquid chromatography system coupled to linear trap quadrupole-Orbitrap mass spectrometer. We identified large number of proteins in each group, of which many were exclusively present in individual patient groups. A total of 53 proteins were common in all patients but were absent in the controls. The majority of the proteins were functionally binding, biologically involved in metabolic processes, and showed enrichment of alternative complement and blood coagulation pathways. In addition to identifying reported proteins such as α2-HS-glycoprotein and Vitamin D binding protein, we detected novel proteins such as CD59, extracellular matrix protein 1 (ECM1), factor H, and myoglobin in the urine of macroalbuminuria patients. ECM1 and factor H are known to influence mesangial cell proliferation, and CD59 causes microvascular damage by influencing membrane attack complex deposition, suggestive their biological relevance to DN. Thus, we have developed a proteome database where various proteins exclusively present in the patients may be further investigated for their role as stage-specific markers and possible therapeutic targets.