Effects of stem cell therapy on protein profile of parkinsonian rats using an18O‐labeling quantitative proteomic approach

The application of neural stem cell (NSC) research to neurodegenerative diseases has led to promising clinical trials. Currently, NSC therapy is most promising for Parkinson's disease (PD). We conducted behavioral tests and immunoassays for the profiling of a PD model in rats to assess the therapeutic effects of NSC treatments. Further, using a multiple sample comparison workflow, combined with ¹⁸O‐labeled proteome mixtures, we compared the differentially expressed proteins from control, PD, and NSC‐treated PD rats. The results were analyzed bioinformatically and verified by Western blot. Based on our initial findings, we believe that the proteomic approach is a valuable tool in evaluating the therapeutic effects of NSC transplantation on neurodegenerative disorders.     

Role of proteomic technologies in understanding risk of arterial thrombosis

Arterial thrombosis is a pivotal event in the development of cardiovascular diseases. Plasma and cellular proteins have the potential to influence thrombus morphology and function. This review summarizes the latest studies to use proteomic technologies to characterize the cellular and plasma components involved in arterial thrombosis, with a view to understanding the pathogenesis and treatment of acute cardiovascular diseases. Proteomic approaches have been extensively used to profile the proteome of endothelial cells, leukocytes, vascular smooth muscle cells, platelets and plasma in the search for risk factors for cardiovascular disease; however, further work is required to validate the direct contribution of these proteins to arterial thrombosis.     

Platelet biomarkers for a descending cognitive function: A proteomic approach

Memory loss is the most common clinical sign in Alzheimer''s disease (AD); thus, searching for peripheral biomarkers to predict cognitive decline is promising for early diagnosis of AD. As platelets share similarities to neuron biology, it may serve as a peripheral matrix for biomarkers of neurological disorders. Here, we conducted a comprehensive and in‐depth platelet proteomic analysis using TMT‐LC‐MS/MS in the populations with mild cognitive impairment (MCI, MMSE = 18–23), severe cognitive impairments (AD, MMSE = 2–17), and the age‐/sex‐matched normal cognition controls (MMSE = 29–30). A total of 360 differential proteins were detected in MCI and AD patients compared with the controls. These differential proteins were involved in multiple KEGG pathways, including AD, AMP‐activated protein kinase (AMPK) pathway, telomerase RNA localization, platelet activation, and complement activation. By correlation analysis with MMSE score, three positively correlated pathways and two negatively correlated pathways were identified to be closely related to cognitive decline in MCI and AD patients. Partial least squares discriminant analysis (PLS‐DA) showed that changes of nine proteins, including PHB, UQCRH, CD63, GP1BA, FINC, RAP1A, ITPR1/2, and ADAM10 could effectively distinguish the cognitively impaired patients from the controls. Further machine learning analysis revealed that a combination of four decreased platelet proteins, that is, PHB, UQCRH, GP1BA, and FINC, was most promising for predicting cognitive decline in MCI and AD patients. Taken together, our data provide a set of platelet biomarkers for predicting cognitive decline which may be applied for the early screening of AD.     

Proteomic surveillance of autoantigens in patients with Behcet's disease by a proteomic approach

To promote an understanding of autoimmunity in BD, we surveyed autoAgs in patients with BD and investigated the prevalence and clinical significance of the identified autoAbs. Specifically, proteins, extracted from peripheral blood mononuclear cells and separated by 2DE, were subjected to WB, using five serum samples from patients with BD. The detected candidate autoAgs were identified by mass spectrometry. As a result, 17 autoantigenic spots were detected by the 2DE‐WB, out of which eight spots were identified. They are enolase‐1, cofilin‐1, vimentin, Rho‐GDI β protein, tubulin‐like protein, and actin‐like proteins. The autoAbs to one of the identified proteins, cofilin‐1, were investigated by WB using a recombinant protein in 30 patients with BD, 35 patients with RA, 32 patients with SLE, and 16 patients with PM/DM. The autoAbs to cofilin‐1 were detected by WB in four (13.3%) of the 30 patients with BD, five (14.3%) of the 35 patients with RA, two (6.3%) of the 32 patients with SLE, and eight (24.2%) of the 33 patients with PM/DM. Our data indicate that the generation of autoAbs to cofilin‐1 may reflect common immunological disorders in BD, RA, and PM/DM. Our data would help understanding of the immunopathology of BD. In addition, the proteomic approach would be a useful way to investigate autoAgs.     

Effects of diterpene forskolin on the release reaction and protein phosphorylation of human platelets

The effects of diterpene forskolin on the human platelet release reaction and on platelet protein phosphorylation were studied. This drug is shown to have the same effects as other agents which increase cAMP levels, namely, it inhibits the secretory response to diverse agonists and causes changes in the phosphorylation of several specific proteins. An increase of the ³²P content is seen in the MW 47 000, 24 000 and 21 000 polypeptides while a decrease is observed in the MW 41 000 and 27 000 and 20 000 species. Forskolin also inhibits the changes in protein phosphorylation pattern induced by the powerful platelet secretagogue, thrombin. Our results relate the effects of antagonists of platelet secretion such as prostaglandins more closely to changes in cAMP levels and in protein phosphorylation than to other possible effects of the receptor–ligand interaction, which is by-passed by the use of forskolin. Our results also provide additional evidence involving these changes in the mechanisms which regulate the secretory process in platelets.     

Response of Alvinella pompejana to variable oxygen stress: A proteomic approach

Alvinella pompejana is one of the most emblematic species of the animal communities colonizing the deep‐sea hydrothermal vents of the East Pacific Rise. This extreme environment is characterized by high temporal variability of its physical–chemical parameters. Among these, the variation in concentration of available oxygen should lead to a specific physiological adaptive response of the animal. To evaluate the mechanisms of this response at a molecular level, a classical 2‐DE‐based proteomic approach has been implemented. After collection (Garrett‐18S and ‐17S vent sites) animals were reconditioned in a high‐pressure chamber pressurized at 260 bar and then the oxygen concentration was regulated to a constant value corresponding to hypoxia, normoxia or hyperoxia for 7 h. The soluble proteins from gills were then analyzed by 2‐DE. The protein content of spots showing specific changes following oxygen concentration variation was determined based on comparison of MS/MS sequence data with a recently established A. pompejana ESTs database. Fifteen proteins, belonging mainly to three families, cytoskeleton protein, enzymes of energetic metabolism and heat shock proteins, have been identified as potentially involved in the response to the change in oxygen concentration. The significance of the relatively small set of proteins modulated by oxygen variations is discussed in the context of a potential universal cellular response to stress.     

Selenium in platelets

Blood and its main components are commonly used to detect states of selenium deficiency. In order to examine whether human platelets are able to provide better or additional information, improvements analytical method resulted in surprisingly narrow normal ranges for selenium and other mineral elements using neutron activation analysis (NAA) and atomic absorption spectrophotometry (AAS), and controlling thermal neutron flux, (n,γ)-cross sections, mean platelet wet wt, and water fraction of the platelets. Previously reported selenium concentrations in platelets on wet wt basis in the order of 500 ng/g—half of which had been found to derive from early bone marrow precursors using⁷⁴Se-selenite—were reproduced by NAA and AAS. However, with the new analytical method the selenium concentrations showed a narrower normal range than that of plasma. Moreover, platelet selenium did not in all cases correlate with plasma selenium. Cellular tissues such as platelets should, therefore, help to detect latent states of selenium deficiency.     

Increased level of fibrinogen chains in the proteome of blood platelets in secondary progressive multiple sclerosis patients

Epidemiological studies indicate a high risk of stroke, heart failure and myocardial infarction in patients with multiple sclerosis, especially in its secondary progressive (SPMS) phase. Some ischaemic events are directly associated with abnormal platelet functions and their prothrombotic activity. Recent reports, including this study, confirm the increased activation of circulating platelets in SPMS, and also show increased platelet reactivity, among other responses, as well as strong aggregation. In this current study, we conducted a comparative analysis of the platelet proteome in SPMS patients and in healthy controls, to demonstrate the quantitative and qualitative differences likely to affect functional changes observed in SPMS. During densitometry evaluation of 2‐D fluorescence difference gel electrophoresis, we observed differences between the electrophoretic patterns of SPMS platelets and the control samples. To determine a detailed characterisation of the proteome changes in the SPMS patients’ blood platelets, in the next stage, we performed mass spectrometry of selected spots and indicated the increased presence of four proteins (fibrinogen, α‐2 macroglobulin, septin‐14 and tubulin β‐1 chain). The most important of these is the increased amount of prothrombotic protein, fibrinogen, which seems to confirm the accuracy of the imaging and potentially explains the increased risk of platelet‐origin thrombotic events. This study provides new knowledge of the potential existence of the molecular mechanisms responsible for the acceleration of the platelet pro‐coagulant function in SPMS. This can help to identify new targets for therapy, which can then be used not only in the second stage of the disease.     

Proteomics investigation of protein expression changes in ouabain induced apoptosis in human umbilical vein endothelial cells

Ouabain is Na(+)/K(+)-ATPase inhibitor and an endogenous regulator of blood pressure, it has dual effect on vascular endothelial cells(VEC) cell growth and VEC apoptosis is contributed to vascular dysfunction involved in vascular remolding. However, the precise mechanisms of apoptosis induced by ouabain remained unclear. The objective of this study was to identify the differently expressed proteins involved in VEC apoptosis induced by ouabain in order to explore cellular and subcellular mechanisms related to ouabain actions. Human umbilical vein endothelial cells (HUVEC) were exposed to increasing concentrations (0.1 nM to 10 microM) of ouabain at 12-48 h intervals. Cell viability tests revealed that high concentrations of ouabain inhibited cell growth. Flow cytometry and caspase-3 activity analysis confirmed that apoptosis was primarily responsible for ouabain induced cell death. Two-dimensional electrophoresis in conjunction with mass spectrometry revealed that the ouabain-induced apoptosis was accompanied by regulated expression of programmed cell death protein 6, cytochrome C1, endothelin converting enzyme, claudin-1, reticulon-4, galectin-1, ras-related protein rab-11B, calnexin, profilin-1 and heat shock protein 60 (HSP60). Further study on cytochrome c and HSP60 demonstrated that levels of mitochondria and cytosol cytochrome c and HSP60 changed in response to ouabain treatment. Data showed that mitochondria proteins such as HSP60 interferes with HSP60-Bax interactions played an important role in ouabain induced apoptosis. These data bring new sights into physiological role for ouabain in VEC apoptosis and vascular remodeling, thus provide new strategies for new anti-cardiovascular disease drug development or the identification of biomarkers for vascular dysfunction in ouabain related hypertension.     

A proteomic approach towards the identification of the matrix protein content of the two types of microbodies in Neurospora crassa

Microbodies (peroxisomes) comprise a class of organelles with a similar biogenesis but remarkable biochemical heterogeneity. Here, we purified the two distinct microbody family members of filamentous fungi, glyoxysomes and Woronin bodies, from Neurospora crassa and analyzed their protein content by HPLC/ESI‐MS/MS. In the purified Woronin bodies, we unambiguously identified only hexagonal 1 (HEX1), suggesting that the matrix is probably exclusively filled with the HEX1 hexagonal crystal. The proteomic analysis of highly purified glyoxysomes allowed the identification of 191 proteins. Among them were 16 proteins with a peroxisomal targeting signal type 1 (PTS1) and three with a PTS2. The collection also contained the previously described N. crassa glyoxysomal matrix proteins FOX2 and ICL1 that lack a typical PTS. Three PTS1 proteins were identified that likely represent the long sought glyoxysomal acyl‐CoA dehydrogenases of filamentous fungi. Two of them were demonstrated by subcellular localization studies to be indeed glyoxysomal. Furthermore, two PTS proteins were identified that are suggested to be involved in the detoxification of nitroalkanes. Since the glyoxysomal localization was experimentally demonstrated for one of these enzymes, a new biochemical reaction is expected to be associated with microbody function.     

Effects of intravenous epinephrine on macaque platelets

Blood was obtained from three species of macaques for a study of platelets. A rapidly mobilizable platelet pool was demonstrated in rhesus macaques given intravenous epinephrine. The number of platelets/ml of blood increased about 30% 3 to 5 min after epinephrine was given. The size distributions of the platelets were similar before and after injection. Platelet aggregability was increased after injection. Basal platelet aggregabilities, as measured by platelet aggregate ratios, were similar in rhesus macaques. Celebes black macaques, and human subjects, but were significantly greater in cynomolgus macaques than in the other three species.     

Characterization of mature rat oligodendrocytes: a proteomic approach

Oligodendrocytes are glial cells responsible for the synthesis and maintenance of myelin in the central nervous system (CNS). Oligodendrocytes are vulnerable to damage occurring in a variety of neurological diseases. Understanding oligodendrocyte biology is crucial for the dissemination of de- and remyelination mechanisms. The goal of the present study is the construction of a protein database of mature rat oligodendrocytes. Post-mitotic oligodendrocytes were isolated from mature Wistar rats and subjected to immunocytochemistry. Proteins were extracted and analyzed by means of two-dimensional gel electrophoresis and two-dimensional liquid chromatography, both coupled to mass spectrometry. The combination of the gel-based and gel-free approach resulted in confident identification of a total of 200 proteins. A minority of proteins were identified in both proteomic strategies. The identified proteins represent a variety of functional groups, including novel oligodendrocyte proteins. The results of this study emphasize the power of the applied proteomic strategy to study known or to reveal new proteins and to investigate their regulation in oligodendrocytes in different disease models.     

Global quantitative proteomic analysis profiles host protein expression in response to Sendai virus infection

Sendai virus (SeV) is an enveloped nonsegmented negative‐strand RNA virus that belongs to the genus Respirovirus of the Paramyxoviridae family. As a model pathogen, SeV has been extensively studied to define the basic biochemical and molecular biologic properties of the paramyxoviruses. In addition, SeV‐infected host cells were widely employed to uncover the mechanism of innate immune response. To identify proteins involved in the SeV infection process or the SeV‐induced innate immune response process, system‐wide evaluations of SeV–host interactions have been performed. cDNA microarray, siRNA screening and phosphoproteomic analysis suggested that multiple signaling pathways are involved in SeV infection process. Here, to study SeV–host interaction, a global quantitative proteomic analysis was performed on SeV‐infected HEK 293T cells. A total of 4699 host proteins were quantified, with 742 proteins being differentially regulated. Bioinformatics analysis indicated that regulated proteins were mainly involved in “interferon type I (IFN‐I) signaling pathway” and “defense response to virus,” suggesting that these processes play roles in SeV infection. Further RNAi‐based functional studies indicated that the regulated proteins, tripartite motif (TRIM24) and TRIM27, affect SeV‐induced IFN‐I production. Our data provided a comprehensive view of host cell response to SeV and identified host proteins involved in the SeV infection process or the SeV‐induced innate immune response process.     

Quantitative proteomic profiling identifies global protein network dynamics in murine embryonic heart development

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Inside human aortic stenosis: a proteomic analysis of plasma

Valvular aortic stenosis (AS) produces a slowly progressive obstruction in left ventricular outflow track. For this reason, aortic valve replacement is warranted when the valvular stenosis is hemodinamically significant, becoming the most common worldwide cause of aortic valve surgery. Recent epidemiologic studies have revealed an association between degenerative AS and cardiovascular risk factors for atherosclerosis, althought reducing the exposure to such factors and statin therapies both fail to delay or reverse the pathology. Hence, a deeper understanding of the pathophysiology of this disease is required to identify appropriate preventive measures. A proteomic analysis of plasma will permit to know and identify the changes in protein expression induced by AS in this tissue. Using two-dimensional difference gel electrophoresis (2D-DIGE) followed by mass spectrometry (MS), we compared the crude (not pre-fractioned) and pre-fractioned plasma from AS patients and control subjects. We sought to identify plasma proteins whose expression is modified in AS. In addition we investigated if crude plasma presented some alterations in the more abundant proteins since to date, has never been studied before. We also further investigated the link between this disease and atherosclerosis with a view to identifying new potential markers and therapeutic targets.     

Annexin V relocates to the periphery of activated platelets following thrombin activation: an ultrastructural immunohistochemical approach

We have previously shown biochemically that the physiological agonist thrombin can cause translocation of endogenous annexin V to a fraction containing all platelet membranes. This paper reports ultrastructural immunohistochemical data revealing that annexin V molecules localize with plasma membranes of blood platelets following thrombin activation. When ultrathin sections of resting platelets were examined by immunogold staining, annexin V was found to be cytosolic, having a generalized distribution throughout the platelet. After thrombin activation, annexin V became peripheral in location and plasmalemma association increased. Morphometric analysis of gold particles shows that annexin V relocates specifically to the plasma membrane and its underlying cytoskeleton following treatment with thrombin. In control platelets 6.1% +/- 0.78 of annexin V is present at the plasma membrane and 15.0% +/- 0.82 in the region corresponding to the membrane cytoskeleton (10-80 nm); after stimulation with 0.5 unit/ml thrombin for 2 min this increased to 16.7% +/- 0.22 and 40.4% +/- 0.53, respectively.