Characterization of low molecular weight urinary proteins at varying time intervals in type 2 diabetes mellitus and diabetic nephropathy patients

Abstract

Background To identify low molecular weight urinary proteins capable of detecting diabetic nephropathy patients which may predict renal alterations at early stages and prevent it from worsening further. Method Three hundred ninety (390) age-matched subjects were divided into 8 groups depending upon duration of diabetes and the severity of renal damage. Urinary proteome profile of all subjects was determined with the help of microfluidic array. Participants with similar profile were further selected to study proteome map of urinary low molecular weight proteins with the help of 2 dimensional gel electrophoresis. Results Out of 390 total patients 268 patients showed a similar one dimensional proteomic pattern. Further, two-dimensional urinary proteomic pattern of these patients with molecular weight < 50 kDa was studied. Eight proteins with molecular weight 11, 15, 17, 23, 34, 38 and 46 kDa were identified with MALDI-QTOF. These low molecular weight proteins showed gradual increase in urinary excretion along with the duration of diabetes and severity of renal damage. Conclusion The study concludes that proteomic analysis might be a useful tool for detecting some novel markers capable of detecting patients susceptible to diabetic nephropathy in the early phase. Electronic supplementary material The online version of this article (10.1186/s13098-019-0430-1) contains supplementary material, which is available to authorized users.

Urinary Protein and Peptide Markers in Chronic Kidney Disease

“…Overall, the aforementioned DN markers may reflect the processes of tubular atrophy and tubulointerstitial fibrosis, many of which are important for DN prognosis. Zinc-α2glycoprotein, transthyretin, and AMBP should be especially noted, as their prognostic significance was confirmed in at least two independent studies [71,74,75].…”

“…This seems to be the most important goal for further proteomics research. ↑ [74] Cytoskeletal keratins type I (10) and type 2 (1, 5) ↑ [59] ICAM1 ↑ [60] Metalloproteinase inhibitor 1 ↑ [60] Antitrombin III ↑ [60,63] Adiponectin ↑ [60] α-2-macroglobulin ↑ [63] Ceruloplasmin ↑ [63,65] ↑ [73] Complement C4a ↑ [63] Haptoglobin ↑ [63] ↑ [68] ↑ [75] Prothrombin ↑ [63] LG3 fragment of endorepellin ↓ [64] Glycoprotein 2 ↑ [36] Vasorin ↑ [36] ↓ [65] Epidermal growth factor ↑ [36] CMRF35-like molecule 9 ↑ [36] Protocadherin ↑ [36] Utreoglobin ↑ [36] Dipeptidyl peptidase IV ↑ [36] NHL repeat-containing protein 3 ↑ [36] SLAM family member 5 (CD84) ↑ [36] Aminopeptidase N ↓ [65] Fibulin-5 ↓ [108] YIP1 family member 3 ↓ [108] Prasoposin ↓ [108] Osteopontin ↓ [108] ↑ [110] Small proline-rich protein 3 ↑ [108] ↓ [54] Leucine-rich repeat-containing protein 25 ↑ [54] ↓ [54] 3340 and 39110 (m/z) ↑ [66] Hepcidin ↑ [67] Protein S89-A9 ↑ [54] α-1 anti-chymotrypsin (SERPINA3) ↑ [68,69] ...…”

“…The array of potential specific DN markers in the urine includes >10 proteins (Table 2), with increased levels of vitamin D-binding protein, calgranulin B, hemopexin [71], zinc-α2-glycoprotein [71,74], 408 N-linked glycoproteins [73], cystatin C, ubiquitin, α-1-acid glycoprotein 1, pigment epithelium-derived factor [74], Clara cell protein CC16 [76], and fibronectin [110], as well as decreased levels of transthyretin [71,74] and differently changing levels of the α-1 microglobulin/bicunin precursor (AMBP) [71,74,75].…”

“…A longitudinal study of type 2 DM revealed an increase in urine transthyretin/prealbumin and the Ig kappa C chain region within 0-5 years of the onset of DM; the appearance of cystatin C and ubiquitin after 5-10 years; and the detection of α-1-acid glycoprotein 1, apolipoprotein A1, AMBP, pigment epithelium-derived factor, and zinc α-2-glycoprotein after 10-20 years [74]. The nonenzymatic glycation of these proteins and their peptides interferes with normal tubular reabsorption and may lead to damage to the proximal tubules and the direct excretion of the proteins into urine.…”

Molecular Pathways of Diabetic Kidney Disease Inferred from Proteomics

“… 29 Through the use of a 2D-DIGE-MALDIQ-TOF strategy and related techniques, Patel et al were able to detect novel DKD-related protein biomarkers in at-risk individuals corresponding to the processes of renal tubulointerstitial fibrosis and tubulointerstitial fibrosis, including apolipoprotein A1, α-1microglobulin, and zinc α-2 glycoprotein. 30 , 31 Guo et al discovered that - 1-antitrypsin - 1-acid glycoprotein, ceruloplasmin, prostate stem cell antigen, APOA4 and other apolipoprotein AIV are prospective protein biomarkers of DKD in 23 diabetic patients and 16 healthy volunteers. 32 Liao et al also observed a significant increase in urinary haptoglobin (Hp) levels in DKD patients, allowing for the more accurate diagnosis and prognostic assessment of individuals with this disease.…”