Salivary psoriasin (S100A7) correlates with diffusion capacity of carbon monoxide in a large cohort of systemic sclerosis patients

Background: Systemic sclerosis (SSc) is an autoimmune disease characterized by progressive fibrosis of the skin and the internal organs. In a previous work we suggested a correlation between levels of salivary psoriasin (S100A7) and pulmonary involvement in SSc patients. The goals of this study are to determine the distribution characteristics of psoriasin in whole saliva (WS) of SSc and healthy donor populations and define its predictive value on diffusion capacity of carbon monoxide (DLCO), along with others clinical parameters. Methods: Salivary level of psoriasin was determined by ELISA kit in 134 SSc patients, 63 Raynaud syndrome patients, 40 patients affected by other connective diseases (non-case) and 74 healthy control subjects. Results: A significant increase of salivary psoriasin was observed in SSc patients when compared with other healthy and pathological controls. Moreover, we confirmed the efficacy of salivary psoriasin to correlate with DLCO in a large cohort of SSc patients. Conclusions: Overall our results suggest a rapid, non invasive and low costing method which can help clinicians in the evaluation of SSc pulmonary involvement

Platelet proteome and clopidogrel response in patients with stable angina undergoing percutaneous coronary intervention

Objectives: We analyzed the platelet proteome of circulating platelets during the onset of clopidogrel therapy in patients with stable angina underwent percutaneous coronary intervention in order to investigate the mechanisms that control platelet reactivity and clopidogrel response in this context. Design & methods: Twenty patients were enrolled in this study. Blood samples were collected before coronary angiography (T0), 12 h after 600 mg of clopidogrel (T1) and 24 h after percutaneous coronary intervention (PCI) (T2). Platelet reactivity, Clopidogrel response and proteomic analysis were examined. Results: Clopidogrel loading dose produced a significant inhibition in all markers of platelet activation in both flow cytometry and aggregation tests. Among the proteins found differentially expressed, eighteen were identified by MS/MS analysis and they resulted involved in the cytoskeleton rearrangement (profilin-1, calpain, α-soluble NSF attachment protein, thrombospondin), in the energetic metabolism (ubiquitin-like modifier-activating enzyme 1, protein-L-isoaspartate-(D-aspartate) O-methyltransferase and nucleoside diphosphate kinase B) and in the oxidative stress (heat shock 70 kDa protein 5 and anti-stress induced phosphoprotein 1. Conclusions: The present study provides novel information on platelet proteome changes associated with platelet activation and clopidogrel response. This investigation supports the development of further proteomic studies for the identification of novel platelet biomarkers

Proteomic analysis of saliva: a unique tool to distinguish primary Sjogren's syndrome from secondary Sjogren's syndrome and other sicca syndromes

Introduction: A growing interest has arisen in salivary proteomics as a tool for the identification of biomarkers for primary Sjogren's syndrome (pSS). Nonetheless, only a limited number of preclinical validation studies have been performed, limiting the possibility of translating proteomic results into clinical practice. The primary aim of this study was to refine the diagnostic power of a panel of candidate salivary biomarkers described in pSS with respect to both healthy volunteers and pathological controls. We also explored the pathogenetic function of the detected putative biomarkers both in the local exocrinopathy and in the systemic inflammatory processes of SS. Methods: One hundred and eighty patients were included in the study overall. In the first "exploratory phase", we enrolled 40 females with pSS, 40 sex-and age-matched healthy volunteers, 10 patients with sicca non-SS and 15 secondary SS (sSS) patients. The testing cohort of the second "challenge phase" of the study was represented by 75 unselected, consecutive subjects: 19 pSS, 21 healthy volunteers, 10 sicca non-SS and 25 sSS patients. Salivary proteomic analysis was performed combining two-dimensional electrophoresis (2DE) and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). Western blot (WB) analysis and enzyme-linked immunosorbent assay (ELISA) were employed to validate 2DE results. Ingenuity Pathway Analysis (IPA) Knowledge base was adopted to associate candidate biomarkers in a signalling pathogenetic network. Results: A total of 28, 6, 7 and 12 protein spots were found to be significantly different in pSS samples with respect to healthy volunteers, non-SS sicca syndrome, SSc-sSS and rheumatoid arthritis-sSS, leading to the identification of 15 differently expressed proteins. Among them, alpha-amylases precursor, carbonic anhydrase VI, beta-2 microglobulin, glyceraldehydes-3-phosphate dehydrogenase (G3PDH), epidermal fatty acid binding protein (E-FABP) and immunoglobulin k light chain (IGK-light chain) apparently showed the most significant differences in pSS when compared to healthy volunteers and non-SS pathological controls. On the other hand, as expected, pSS and sSS salivary profiles shared a great number of similarities. Conclusions: This study demonstrated that salivary fluid might represent a novel ideal milieu for the detection of a diagnostic panel of candidate biomarkers for pSS, and to gain an insight into the pathogenetic processes underlying glandular and systemic autoimmune disorders

Palmitate-induced lipotoxicity alters acetylation of multiple proteins in clonal β cells and human pancreatic islets

Type 2 diabetes is characterized by progressive β cell dysfunction, with lipotoxicity playing a possible pathogenetic role. Palmitate is often used to examine the direct effects of lipotoxicity and it may cause mitochondrial alterations by activating protein acetylation. However, it is unknown whether palmitate influences protein acetylation in β cells. We investigated lysine acetylation in mitochondrial proteins from INS-1E β cells (INS-1E) and in proteins from human pancreatic islets (HPI) after 24 h palmitate exposure. First, we confirmed that palmitate damages β cells and demonstrated that chemical inhibition of deacetylation also impairs INS-1E function and survival. Then, by 2-D gel electrophoresis, Western Blot and Liquid Chromatography-Mass Spectrometry we evaluated the effects of palmitate on protein acetylation. In mitochondrial preparations from palmitate-treated INS-1E, 32 acetylated spots were detected, with 13 proteins resulting over-acetylated. In HPI, 136 acetylated proteins were found, of which 11 were over-acetylated upon culture with palmitate. Interestingly, three proteins, glutamate dehydrogenase, mitochondrial superoxide dismutase, and SREBP-1, were over-acetylated in both INS-1E and HPI. Therefore, prolonged exposure to palmitate induces changes in β cell protein lysine acetylation and this modification could play a role in causing β cell damage. Dysregulated acetylation may be a target to counteract palmitate-induced β cell lipotoxicity

Bottom-up proteomics suggests an association between differential expression of mitochondrial proteins and chronic fatigue syndrome

Chronic fatigue syndrome (CFS) is a debilitating and complex disorder characterized by unexplained fatigue not improved by rest. An area of investigation is the likely connection of CFS with defective mitochondrial function. In a previous work, we investigated the proteomic salivary profile in a couple of monozygotic twins discordant for CFS. Following this work, we analyzed mitochondrial proteins in the same couple of twins. Nano-liquid chromatography electrospray ionization mass spectrometry (nano-LC-MS) was used to study the mitochondria extracted from platelets of the twins. Subsequently, we selected three proteins that were validated using western blot analysis in a big cohort of subjects (n=45 CFS; n=45 healthy), using whole saliva (WS). The selected proteins were as follows: Aconitate hydratase (ACON), ATP synthase subunit beta (ATPB) and malate dehydrogenase (MDHM). Results for ATPB and ACON confirmed their upregulation in CFS. However, the MDHM alteration was not confirmed. Thereafter, seeing the great variability of clinical features of CFS patients, we decided to analyze the expression of our proteins after splitting patients according to clinical parameters. For each marker, the values were actually higher in the group of patients who had clinical features similar to the ill twin. In conclusion, these results suggest that our potential markers could be one of the criteria to be taken into account for helping in diagnosis. Furthermore, the identification of biomarkers present in particular subgroups of CFS patients may help in shedding light upon the complex entity of CFS. Moreover, it could help in developing tailored treatments

Comparative proteomic analysis of malignant pleural mesothelioma: Focusing on the biphasic subtype

Malignant pleural mesothelioma (MPM) is a rare cancer originated from pleural mesothelial cells. MPM has been associated with long-term exposure to asbestos. In this work we performed a comparative proteomic analysis of biphasic pleural mesothelioma (B-PM). Tissue biopsies were obtained from 61 patients who were subjected to a diagnostic thoracoscopy. 2D/MS based approach was used for proteomic analysis. The 22 proteins found differentially expressed in B-PM, with respect to benign, were analyzed by Ingenuity Pathways Analysis and compared with those obtained for epitheliod pleural mesothelioma (E-PM). A different activation of transcription factors, proteins and cytokines were observed between two subtypes

Putative biomarkers for malignant pleural mesothelioma suggested by proteomic analysis of cell secretome

Background: Malignant pleural mesothelioma (MPM) a rare neoplasm linked to asbestos exposure is characterized by a poor prognosis. Soluble mesothelin is currently considered the most specific diagnostic biomarker. The aim of the study was to identify novel biomarkers by proteomic analysis of two MPM cell lines secretome. Materials and Methods: The protein patterns of MPM cells secretome were examined and compared to a non-malignant mesothelial cell line using two-dimensional gel electrophoresis coupled to mass spectrometry. Serum levels of candidate biomarkers were determined in MPM patients and control subjects. Results: Two up-regulated proteins involved in cancer biology, prosaposin and quiescin Q6 sulfhydryl oxidase 1, were considered candidate biomarkers. Serum levels of both proteins were significantly higher in MPM patients than control subjects. Combining the data of each receiver-operating characteristic analysis predicted a good diagnostic accuracy. Conclusion: A panel of the putative biomarkers represents a promising tool for MPM diagnosis

Colon cancer diagnosis: a proteomic approach to search potential biomarkers

Comunicaciones a congreso

[MALDI-TOF and SELDI-TOF analysis: "tandem" techniques to identify potential biomarker in fibromyalgia].

Fibromyalgia (FM) is characterized by the presence of chronic widespread pain throughout the musculoskeletal system and diffuse tenderness. Unfortunately, no laboratory tests have been appropriately validated for FM and correlated with the subsets and activity. The aim of this study was to apply a proteomic technique in saliva of FM patients: the Surface Enhance Laser Desorption/Ionization Time-of-Flight (SELDI-TOF). For this study, 57 FM patients and 35 HC patients were enrolled. The proteomic analysis of saliva was carried out using SELDI-TOF. The analysis was performed using different chip arrays with different characteristics of binding. The statistical analysis was performed using cluster analysis and the difference between two groups was underlined using Student's t-test. Spectra analysis highlighted the presence of several peaks differently expressed in FM patients compared with controls. The preliminary results obtained by SELDI-TOF analysis were compared with those obtained in our previous study performed on whole saliva of FM patients by using electrophoresis. The m/z of two peaks, increased in FM patients, seem to overlap well with the molecular weight of calgranulin A and C and Rho GDP-dissociation inhibitor 2, which we had found up-regulated in our previous study. These preliminary results showed the possibility of identifying potential salivary biomarker through salivary proteomic analysis with MALDI-TOF and SELDI-TOF in FM patients. The peaks observed allow us to focus on some of the particular pathogenic aspects of FM, the oxidative stress which contradistinguishes this condition, the involvement of proteins related to the cytoskeletal arrangements, and central sensibilization