Two-dimensional gel electrophoresis approach for CTL phosphoproteome analysis.

Phosphorylation of proteins plays a pivotal role in signal transduction processes, and it is a key regulator of many biological cell functions. Various strategies have been proposed for the study of phosphoproteome; most of them require a multi-step analysis and sophisticated equipment. Here we describe the two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) analysis of PBMC phosphoproteome using as preliminary enrichment step a simple phosphoprotein isolation by lanthanum chloride. This strategy can be most certainly applied to study the phosphoproteome of CTLs isolated from PBMCs. The phosphoproteome analysis of PBMCs, as well as of CTLs, may help to reveal the signaling pathways essential to their biological role in health and disease

Erratum to: Proteomics and diabetic nephropathy: what have we learned from a decade of clinical proteomics studies?

Diabetic nephropathy (DN) has become the most frequent cause of chronic kidney disease worldwide due to the constant increase of the incidence of type 2 diabetes mellitus in developed and developing countries. The understanding of the pathophysiological mechanisms of human diseases through a large-scale characterization of the protein content of a biological sample is the key feature of the proteomics approach to the study of human disease. We discuss the main results of over 10 years of tissue and urine proteomics studies applied to DN in order to understand how far we have come and how far we still have to go before obtaining a full comprehension of the molecular mechanisms involved in the pathogenesis of DN and identifying reliable biomarkers for accurate management of patients

Microbiota issue in CKD: how promising are gut-targeted approaches?

In chronic kidney disease (CKD), the progressive decline in the renal excretory function leads to accumulation of urea and toxins in the blood. The CKD-associated dysbiosis of gut microbiota further contributes to uremia by increasing intestinal toxins production. Gut microbiota is involved in a complex network of human organs, mediated by microbial metabolites: in CKD, gut–heart and gut–brain axes may have a role in increased cardiovascular risk and neuropsychiatric disorders. While the cardiovascular toxicity of some microbial molecules is well known, their presumptive neurotoxicity needs to be confirmed by specific studies. In this review, we describe gut–heart and gut–brain axes in CKD, with an overview of the experimental and human studies characterizing CKD-associated gut microbiota, and we discuss the benefits coming from new approaches aimed at gut manipulation. Microbiota metabolism is emerging as a modifiable non-traditional risk factor in nephrology. In order to take advantage of this issue, it is necessary to consider the microbiota manipulation as part of the nutritional management of CKD. Integrating the low-protein nutritional approach with prebiotic, probiotic and synbiotic supplementation is a promising tool to control disease progression and comorbidities, though an extensive validation in large-scale clinical trials is still required

Metabolic Fingerprinting of Fabry Disease: Diagnostic and Prognostic Aspects

Fabry disease (FD) is an X-linked lysosomal disease due to a deficiency in the activity of the lysosomal-galactosidase A (GalA), a key enzyme in the glycosphingolipid degradation pathway. FD is a complex disease with a poor genotype-phenotype correlation. In the early stages, FD could involve the peripheral nervous system (acroparesthesias and dysautonomia) and the ski (angiokeratoma), but later kidney, heart or central nervous system impairment may significantly decrease life expectancy. The advent of omics technologies offers the possibility of a global, integrated and systemic approach well-suited for the exploration of this complex disease. In this narrative review, we will focus on the main metabolomic studies, which have underscored the importance of detecting biomarkers for a diagnostic and prognostic purpose in FD. These investigations are potentially useful to explain the wide clinical, biochemical and molecular heterogeneity found in FD patients. Moreover, the quantitative mass spectrometry methods developed to evaluate concentrations of these biomarkers in urine and plasma will be described. Finally, the complex metabolic biomarker profile depicted in FD patients will be reported, which varies according to gender, types of mutations, and therapeutic treatment

[Proteomics and the kidney: an innovative approach to the study of renal disease].

In the post human genome era, several ''omics'' fields are emerging. Proteomics has experienced a rapid growth in the recent past and has great potential for the future. Proteomic technologies are used with increasing frequency also in nephrology. The aim of this review is to examine the recent application of emerging proteomic technologies to the study of renal physiology and pathophysiology. We highlight the use in renal research of a number of available techniques including 2-dimensional gel electrophoresis, liquid chromatography/mass spectrometry, surface-enhanced laser desorption/ionization, and capillary electrophoresis/mass spectrometry. We examine the role, efficacy and diagnostic potential of the different proteomic approaches, focusing on current difficulties and potential solutions. The integrating role of bioinformatics and the need for standardized procedures for sample preservation and analysis and reporting of results are also discussed. Although the field is still in an embryonic stage, the knowledge gained up to now is important not only for a better understanding of renal physiology and pathophysiology, but also for the identification of disease markers and the development and follow-up of new therapies. This review gives an overview of proteomics, providing background information, outlining the scopes, highlighting the applications in nephrology, and reporting advantages and limitations

Urine protein profile of IgA nephropathy may predict the response to ACE-inhibitor therapy

This study was aimed at the search of urinary biomarkers which might help to predict the clinical response of IgA nephropathy (IgAN) patients to angiotensin converting enzyme inhibitors (ACEi). First, we studied the urinary proteome of 18 IgAN patients (toward 20 healthy controls) who had been chronically treated with ACEi by using 2-D PAGE coupled to nano-HPLC-ESI-MS/MS analysis. We identified 3 proteins, kininogen (p = 0.02), inter-alpha-trypsin-inhibitor heavy chain 4 (35 kDa fragment) (p = 0.02) and transthyretin (p50% and a stable renal function over time were used to classify patients as responders. Then, we adopted immunoblotting to confirm the predictive power of one of the above proteins, kininogen, in 20 patients with biopsy-proven IgAN, before starting any therapy. Thus, we confirmed that very low levels of kininogen urine excretion were indeed predictive of an inadequate or absent clinical response to ACEi therapy of IgAN patients, after 6-month follow-up. Concluding, the analysis of urine proteome of IgAN patients generated a set of proteins which distinguished subjects responsive to ACEi from those unresponsive to the inhibition of renin-angiotensin system (RAS)