Towards the Definition of the Molecular Hallmarks of Idiopathic Membranous Nephropathy in Serum Proteome: A DIA-PASEF Approach

Abstract

Idiopathic membranous nephropathy (IMN) is a pathologically defined disorder of the glomerulus, primarily responsible for nephrotic syndromes (NS) in nondiabetic adults. The underlying molecular mechanisms are still not completely clarified. To explore possible molecular and functional signatures, an optimised mass spectrometry (MS) method based on next-generation data-independent acquisition combined with ion-mobility was applied to serum of patients affected by IMN (n = 15) or by other glomerulopathies (PN) (n = 15). The statistical comparison highlighted a panel of 57 de-regulated proteins with a significant increase in lipoprotein-related proteins (APOC1, APOB, APOA1, APOL1 and LCAT) and a substantial quantitative alteration of key serpins (including A4, D1, A7, A6, F2, F1 and 1) possibly associated with IMN or NS and podocyte stress. A critical dysregulation in metabolisms of lipids (e.g., VLDL assembly and clearance) likely to be related to known hyperlipidemia in IMN, along with involvement of non-classical complement pathways and a putative enrolment of ficolin-2 in sustaining the activation of the lectin-mediated complement system have been pinpointed. Moreover, mannose receptor CD206 (MRC1-down in IMN) and biotinidase (BTD-up in IMN) are able alone to accurately distinguish IMN vs. PN. To conclude, our work provides key proteomic insights into the IMN complexity, opening the way to an efficient stratification of MN patients.

Feasibility of MALDI-MSI-Based Proteomics Using Bouin-Fixed Pathology Samples: Untapping the Goldmine of Nephropathology Archives

“…nLC-ESI MS/MS analyses were performed coupling the nLC system online with a timsTOF fleX (Bruker Daltonics, Bremen, Germany) mass spectrometer using a CaptiveSpray source, as already described with some modifications. , BFPE and FFPE renal samples at different fixation time points were analyzed with the Evosep One LC system (Evosep Biosystems, Odense, Denmark): 400 ng of peptides for each sample were loaded into a disposable trap column, Evotip Pure (Evosep Biosystems, Odense, Denmark), following the manufacturer protocol. Desalted and concentrated peptides were separated into an analytical 8 cm column (PepSep C18, 8 cm Performance column, a particle size of 1.5 μm, and an internal diameter of 150 μm) at a temperature of 40 °C.…”

Biotin Homeostasis and Human Disorders: Recent Findings and Perspectives

“…According to a recent study, upregulated biotinidase levels were found in idiopathic membranous nephropathy (IMN), i.e., a pathologically defined disorder of the glomerulus, which is primarily responsible for nephrotic syndromes (NSs) in nondiabetic adults. According to the authors, theirs was the first study correlating biotinidase and IMN, and the finding might deserve further investigation [ 181 ]. In another recent study, by employing drug database screening and AutoDock validation, the authors proposed that prostaglandin, valsartan, “biotin A”, luteolin, and curcumin might be potential drugs for antagonizing the plasminogen activator, urokinase receptor (PLAUR), which was identified as an effective diagnostic and possible therapeutic marker for atherosclerosis lesion progression [ 182 ].…”