| 1. |
- Bourdenx, Mathieu, et al.
(författare)
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Abnormal structure-specific peptide transmission and processing in a primate model of Parkinson's disease and L-DOPA-induced dyskinesia
- 2014
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Ingår i: Neurobiology of Disease. - : Elsevier BV. - 0969-9961 .- 1095-953X. ; 62, s. 307-312
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Tidskriftsartikel (refereegranskat)abstract
- A role for enhanced peptidergic transmission, either opioidergic or not, has been proposed for the generation of L-3,4-dihydroxyphenylalanine (L-DOPA)-induced dyskinesia (LID) on the basis of in situ hybridization studies showing that striatal peptidergic precursor expression consistently correlates with LID severity. Few studies, however, have focused on the actual peptides derived from these precursors. We used mass-spectrometry to study peptide profiles in the putamen and globus pallidus (internalis and externalis) collected from 1-methyl-4-phenyl-1,2,4,6-tetrahydropyridine treated macaque monkeys, acutely or chronically treated with L-DOPA. We identified that parkinsonian and dyskinetic states are associated with an abnormal production of proenkephalin-, prodynorphin- and protachykinin-1-derived peptides in both segments of the globus pallidus. Moreover, we report that peptidergic processing is dopamine-state dependent and highly structure-specific, possibly explaining the failure of previous clinical trials attempting to rectify abnormal peptidergic transmission.
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| 2. |
- Furuhjelm, Catrin, et al.
(författare)
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Th1 and Th2 chemokines, vaccine induced 1 immunity and allergic disease in infants after maternal ω-3 fatty acid supplementation during pregnancy and lactation
- 2011
-
Ingår i: Pediatric Research. - : Nature Publishing Group. - 0031-3998 .- 1530-0447. ; 69:3, s. 259-264
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated whether the previously reported preventive effect of maternal ω-3 fatty acid supplementation on IgE-associated allergic disease in infancy may be mediated by facilitating a balanced circulating Th2/Th1 chemokine profile in the infant. Vaccine-induced immune responses at 2 y of age were also evaluated. Pregnant women, at risk of having an allergic infant, were randomized to daily supplementation with 1.6 g eicosapentaenoic acid and 1.1 g docosahexaenoic acid or placebo from the 25th gestational week through 3.5 mo of breastfeeding. Infant plasma was analyzed for chemokines (cord blood, 3, 12, 24 mo) and anti-tetanus and anti-diphtheria IgG (24 mo). High Th2-associated CC-chemokine ligand 17 (CCL17) levels were associated with infant allergic disease (p < 0.05). In infants without, but not with, maternal history of allergy, the ω-3 supplementation was related to lower CCL17/CXC-chemokine ligand 11 (CXCL11) (Th2/Th1) ratios (p < 0.05). Furthermore, in nonallergic, but not in allergic infants, ω-3 supplementation was linked with higher Th1-associated CXCL11 levels (p < 0.05), as well as increased IgG titers to diphtheria (p = 0.01) and tetanus (p = 0.05) toxins. Thus, the prospect of balancing the infant immune system toward a less Th2-dominated response, by maternal ω-3 fatty acid supplementation, seems to be influenced by allergic status.
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| 3. |
- Fälth, Maria, et al.
(författare)
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Analytical utility of small neutral losses from reduced species in electron capture dissociation studied using SwedECD database
- 2008
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 80:21, s. 8089-8094
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Tidskriftsartikel (refereegranskat)abstract
- Small neutral losses from charge-reduced species [M + nH]((n-1)+center dot) is one of the most abundant fragmentation channels in both electron capture dissociation, ECD, and electron transfer dissociation, ETD. Several groups have previously studied these losses on particular examples. Now, the availability of a large (11491 entries) SwedECD database (http://www.bmms.uu.se/CAD/indexECD.html) of high-resolution ECD data sets on doubly charged tryptic peptides has made possible a systematic study involving statistical evaluation of neutral losses from [M + 2H](+center dot) ions. Several new types of losses are discovered, and 16 specific (>94%) losses are characterized according to their specificity and sensitivity, as well as occurrence for peptides of different lengths. On average, there is more than one specific loss per ECD mass spectrum, and two-thirds of all MS/MS data sets in SwedECD contain at least one specific loss. Therefore, specific neutral losses are analytically useful for improved database searching and de novo sequencing. In particular, N and GG isomeric sequences can be distinguished. The pattern of neutral losses was found to be remarkably dissimilar with the losses from radical z(center dot) fragment ions: e.g., there is no direct formation of w ions from the reduced species. This finding emphasizes the difference in fragmentation behaviors of hydrogen-abundant and hydrogen-deficient species.
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| 4. |
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| 5. |
- Fälth, Maria, et al.
(författare)
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Neuropeptidomics strategies for specific and sensitive identification of endogenous peptides
- 2007
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Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 6:7, s. 1188-1197
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Tidskriftsartikel (refereegranskat)abstract
- A new approach using targeted sequence collections has been developed for identifying endogenous peptides. This approach enables a fast, specific, and sensitive identification of endogenous peptides. Three different sequence collections were constituted in this study to mimic the peptidomic samples: SwePep precursors, SwePep peptides, and SwePep predicted. The searches for neuropeptides performed against these three sequence collections were compared with searches performed against the entire mouse proteome, which is commonly used to identify neuropeptides. These four sequence collections were searched with both Mascot and X! Tandem. Evaluation of the sequence collections was achieved using a set of manually identified and previously verified peptides. By using the three new sequence collections, which more accurately mimic the sample, 3 times as many peptides were significantly identified, with a false-positive rate below 1%, in comparison with the mouse proteome. The new sequence collections were also used to identify previously uncharacterized peptides from brain tissue; 27 previously uncharacterized peptides and potentially bioactive neuropeptides were identified. These novel peptides are cleaved from the peptide precursors at sites that are characteristic for prohormone convertases, and some of them have post-translational modifications that are characteristic for neuropeptides. The targeted protein sequence collections for different species are publicly available for download from SwePep.
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| 6. |
- Fälth, Maria, et al.
(författare)
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SwedCAD, a database of annotated high-mass accuracy MS/MS spectra of tryptic peptides
- 2007
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 6:10, s. 4063-4067
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Tidskriftsartikel (refereegranskat)abstract
- A database of high-mass accuracy tryptic peptides has been created. The database contains 15897 unique, annotated MS/MS spectra. It is possible to search for peptides according to their mass, number of missed cleavages, and sequence motifs. All of the data contained in the database is downloadable, and each spectrum can be visualized. An example is presented of how the database can be used for studying peptide fragmentation. Fragmentation of different types of missed cleaved peptides has been studied, and the results can be used to improve identification of these types of peptides.
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| 7. |
- Fälth, Maria, et al.
(författare)
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SwePep – A database designed for endogenous peptides and mass spectrometry
- 2006
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Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 5:6, s. 998-1005
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Tidskriftsartikel (refereegranskat)abstract
- A new database, SwePep, specifically designed for endogenous peptides, has been constructed to significantly speed up the identification process from complex tissue samples utilizing mass spectrometry. In the identification process the experimental peptide masses are compared with the peptide masses stored in the database both with and without possible post-translational modifications. This intermediate identification step is fast and singles out peptides that are potential endogenous peptides and can later be confirmed with tandem mass spectrometry data. Successful applications of this methodology are presented. The SwePep database is a relational database developed using MySql and Java. The database contains 4180 annotated endogenous peptides from different tissues originating from 394 different species as well as 50 novel peptides from brain tissue identified in our laboratory. Information about the peptides, including mass, isoelectric point, sequence, and precursor protein, is also stored in the database. This new approach holds great potential for removing the bottleneck that occurs during the identification process in the field of peptidomics. The SwePep database is available to the public.
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| 8. |
- Fälth, Maria, et al.
(författare)
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Validation of endogenous peptide identifications using a database of tandem mass spectra
- 2008
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 7:7, s. 3049-3053
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Tidskriftsartikel (refereegranskat)abstract
- The SwePep database is designed for endogenous peptides and mass spectrometry. It contains information about the peptides such as mass, p/, precursor protein and potential post-translational modifications. Here, we have improved and extended the SwePep database with tandem mass spectra, by adding a locally curated version of the global proteome machine database (GPMDB). In peptidomic experiment practice, many peptide sequences contain multiple tandem mass spectra with different quality. The new tandem mass spectra database in SwePep enables validation of low quality spectra using high quality tandem mass spectra. The validation is performed by comparing the fragmentation patterns of the two spectra using algorithms for calculating the correlation coefficient between the spectra. The present study is the first step in developing a tandem spectrum database for endogenous peptides that can be used for spectrum-to-spectrum identifications instead of peptide identifications using traditional protein sequence database searches.
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| 9. |
- Fälth Savitski, Maria, 1979-
(författare)
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Improved Neuropeptide Identification : Bioinformatics and Mass Spectrometry
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Bioinformatic methods were developed for improved identification of endogenous peptides using mass spectrometry. As a framework for these methods, a database for endogenous peptides, SwePep, was created. It was designed for storing information about endogenous peptides including tandem mass spectra. SwePep can be used for identification and validation of endogenous peptides by comparing experimentally derived masses of peptides and their fragments with information in the database. To improve automatic peptide identification of neuropeptides, targeted sequence collections that better mimic the peptidomic sample was derived from the SwePep database. Three sequence collections were created: SwePep precursors, SwePep peptides, and SwePep predicted. The searches for neuropeptides performed against these three sequence collections were compared with searches performed against the entire mouse proteome, and it was observed that three times as many peptides were identified with the targeted SwePep sequence collections. Applying the targeted SwePep sequence collections to identification of previously uncharacterized peptides yielded 27 novel potentially bioactive neuropeptides.Two fragmentations studies were performed using high mass accuracy tandem mass spectra of tryptic peptides. For this purpose, two databases were created: SwedCAD and SwedECD for CID and ECD tandem mass spectra, respectively. In the first study, fragmentation pattern of peptides with missed cleaved sites was studied using SwedCAD. It was observed that peptides with two arginines positioned next to each other have the same ability to immobilize two protons as peptides with two distant arginines. In the second study, SwedECD was used for studying small neutral losses from the reduced species in ECD fragmentation. The neutral losses were characterized with regard to their specificity and sensitivity to function as reporter ions for revealing the presence of specific amino acids in the peptide sequence. The results from these two studies can be used to improve identification of both tryptic and endogenous peptides.In summary, a collection of methods was developed that greatly improved the sensitivity of mass spectrometry peptide identification.
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| 10. |
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| 11. |
- Hanrieder, Jörg, 1980, et al.
(författare)
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L-DOPA-induced dyskinesia is associated with regional increase of striatal dynorphin peptides as elucidated by imaging mass spectrometry.
- 2011
-
Ingår i: Molecular & cellular proteomics : MCP. - 1535-9484 .- 1535-9476. ; 10:10
-
Tidskriftsartikel (refereegranskat)abstract
- Opioid peptides are involved in various pathophysiological processes, including algesia, epilepsy, and drug dependence. A strong association between L-DOPA-induced dyskinesia (LID) and elevated prodynorphin mRNA levels has been established in both patients and in animal models of Parkinson's disease, but to date the endogenous prodynorphin peptide products have not been determined. Here, matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) was used for characterization, localization, and relative quantification of striatal neuropeptides in a rat model of LID in Parkinson's disease. MALDI IMS has the unique advantage of high sensitivity and high molecular specificity, allowing comprehensive detection of multiple molecular species in a single tissue section. Indeed, several dynorphins and enkephalins could be detected in the present study, including dynorphin A(1-8), dynorphin B, α-neoendorphin, MetEnkRF, MetEnkRGL, PEnk (198-209, 219-229). IMS analysis revealed elevated levels of dynorphin B, α-neoendorphin, substance P, and PEnk (220-229) in the dorsolateral striatum of high-dyskinetic animals compared with low-dyskinetic and lesion-only control rats. Furthermore, the peak-intensities of the prodynorphin derived peptides, dynorphin B and α-neoendorphin, were strongly and positively correlated with LID severity. Interestingly, these LID associated dynorphin peptides are not those with high affinity to κ opioid receptors, but are known to bind and activate also μ- and Δ-opioid receptors. In addition, the peak intensities of a novel endogenous metabolite of α-neoendorphin lacking the N-terminal tyrosine correlated positively with dyskinesia severity. MALDI IMS of striatal sections from Pdyn knockout mice verified the identity of fully processed dynorphin peptides and the presence of endogenous des-tyrosine α-neoendorphin. Des-tyrosine dynorphins display reduced opioid receptor binding and this points to possible novel nonopioid receptor mediated changes in the striatum of dyskinetic rats. Because des-tyrosine dynorphins can only be detected by mass spectrometry, as no antibodies are available, these findings highlight the importance of MALDI IMS analysis for the study of molecular dynamics in neurological diseases.
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| 12. |
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| 13. |
- Janefjord, Camilla, 1976-
(författare)
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Th1, Th2 and Treg associated factors in relation to allergy
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Immune responses are often divided into T helper 1 (Th1), Th2 and Treg like immunity. Allergy is associated with Th2 like responses to allergens and possibly to reduced regulatory functions. Activation via the CD2 receptor increases the production of the Th1 associated cytokine IFN-g and enhances the responses of activated T cells to IL-12. This may be due to an up-regulation of the signal-transducing β2-chain of the IL-12 receptor. CD2 function may be impaired in allergic children. As IL-12 is a strong promoter of Th1 like responses, this may be one contributing factor to the Th2-skewed immune responses found in allergic children. IL-27 and its receptor component WSX-1 may also play a role in Th1 like responses. The transcription factors T-bet, GATA-3 and Foxp3 are associated with Th1, Th2 and Treg type of immune responses, respectively.Aim: To investigate possible mechanisms behind the reduced Th1 and/or Treg associated immunity in relation to allergy by studying the CD2 induced regulation of IL-12Rβ2, WSX-1, T-bet, GATA-3 and Foxp3, as well as the production of different cytokines in children and adults. The aim was also to study the development of these factors during the first two years of life in relation to development of allergy in children from a country with high (Sweden) and low (Estonia) prevalence of allergy.Material and methods: Four different study groups were included; 32 12-year-old children, 38 7-year-old children, 61 children followed from birth to two years of age and 20 adults. Peripheral blood mononuclear cells were cultured with PHA (which partly signals via CD2), IL-2 and IL-12 alone and in combination or with anti-CD2 alone or combined with anti-CD28 antibodies. mRNA expression of cytokine receptors and transcription factors was analysed with real-time PCR and production of Th1, Th2 and Treg associated cytokines with ELISA.Results: We found lower PHA-induced IL-12Rβ2 and IFN-γ production in 12-year-old children with positive skin prick tests (SPT), compared with SPT negative children. We also found lower IL-2 induced IL-12Rβ2 in children with allergic airway symptoms and high IgE levels compared to children without a history of allergy and low IgE levels. This was accompanied with lower IL-2 and IL-12 induced IFN-γ. The spontaneous mRNA expression of IL-12Rβ2, WSX-1, T-bet, GATA-3 and Foxp3 was similar at birth and at 24 months. PHA induced up-regulation of all markers at all ages except for GATA-3, which was up-regulated in allergic children only at 6 and 12 months. PHA-induced T-bet and WSX-1 increased from birth to 24 months in non-allergic children. At a specific age, similar levels of all markers were found in allergic and non-allergic children, except for higher spontaneous IL-12Rβ2 at 24 months and higher PHA-induced WSX-1 at birth in allergic children. All cytokines increased with age. No clear differences were found between Swedish and Estonian children. CD2 stimulation induced Foxp3 and IL-10, while CD2 together with CD28 stimulation induced both Th1 and Th2 related transcription factors and cytokines. The combination also hampered the CD2 induced expression of Foxp3.Conclusions: The CD2 pathway and the response to IL-2 may be impaired in allergic children as lower IL-12Rβ2 and IFN-g were found in allergic, compared to non-allergic children. This difference was not found in adults. CD2 may be involved in induction of regulatory T cell responses as stimulation via CD2 in the absence of other co-stimulatory molecules induced Foxp3 and IL-10. Different developmental patterns of Th1 and Th2 associated factors may influence the development of allergic diseases in childhood.
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| 14. |
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| 15. |
- Kaplan, Anders, et al.
(författare)
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An Automated Method for Scanning LC−MS Data Sets for Significant Peptides and Proteins, Including Quantitative Profiling and Interactive Confirmation : An Automated Method for Scanning LC−MS Data Sets for Significant Peptides and Proteins, Including Quantitative Profiling and Interactive Confirmation
- 2007
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 6:7, s. 2888-2895
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Tidskriftsartikel (refereegranskat)abstract
- Differential quantification of proteins and peptides by LC-MS is a promising method to acquire knowledge about biological processes, and for finding drug targets and biomarkers. However, differential protein analysis using LC-MS has been held back by the lack of suitable software tools. Large amounts of experimental data are easily generated in protein and peptide profiling experiments, but data analysis is time-consuming and labor-intensive. Here, we present a fully automated method for scanning LC-MS/MS data for biologically significant peptides and proteins, including support for interactive confirmation and further profiling. By studying peptide mixtures of known composition, we demonstrate that peptides present in different amounts in different groups of samples can be automatically screened for using statistical tests. A linear response can be obtained over almost 3 orders of magnitude, facilitating further profiling of peptides and proteins of interest. Furthermore, we apply the method to study the changes of endogenous peptide levels in mouse brain striatum after administration of reserpine, a classical model drug for inducing Parkinson disease symptoms.
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| 16. |
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| 17. |
- Kivling, Anna, et al.
(författare)
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Diverging immune responses when allergy, type 1 diabetes and celiac disease coexist
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- An imbalance between different immune cells, among them T-cells and inflammatory cells, has been proposed to be part of the disease process in type 1 diabetes (T1D), celiac disease and allergy. T-cells and inflammatory cells exert their actions through cytokines and chemokines, and the secretion of those can be used to describe the cell milieu during an immune response. This study included seventy-two children, diagnosed with T1D, celiac disease, allergy, or a combination of two of these diseases and compared to reference children. The study aimed to evaluate the secretion of 27 different cytokines and chemokines in cell culture supernatant after in vitro stimulation with disease-associated antigens (birch, gluten, insulin) detected by Luminex technique. Combination of allergy with either T1D or celiac disease gave diverging results. Children with combination of T1D and allergy showed an increased secretion of several cytokines (IL-2, IL-4, IL-5, IL-7, IL-9, IL-10, IL-12, IL-15, IL-17 and CCL11), in comparison to almost all groups from birch stimulation. In contrast, when allergy was combined with celiac disease, the spontaneous secretion of IL-1β, IL-5, IL-6, IL-9, IL-10, IL-12 and CCL3 was decreased compared to children with T1D or allergy, as well as children with celiac disease alone, children with combination of T1D and allergy and reference children. In conclusion, our results shed some light on the immune responses in children with common immunological diseases. Our study indicates diverging immune responses when allergy, type 1 diabetes and celiac disease coexist.
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| 18. |
- Kivling, Anna, et al.
(författare)
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Diverse FOXP3 Expression in Children with Type 1 Diabetes and Celiac Disease
- 2008
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Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923 .- 1749-6632. ; 1150, s. 273-277
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Tidskriftsartikel (refereegranskat)abstract
- Imbalance between different types of T lymphocytes, such as T helper (Th) and regulatory T cells (Tregs), has been reported to play a part in the pathogenesis behind such autoimmune diseases as type 1 diabetes (T1D) and celiac disease (CD). Defects in Tregs are proposed to at least partly explain the imbalance of Th cells found in children with immunologic diseases. Peripheral blood mononuclear cells from 24 children with T1D and/or CD, and reference children (that is, those without any of these diseases) were stimulated with disease-associated antigens (insulin, gluten, transglutaminase [tTG]), and phytohemagglutinin (PHA). The mRNA expression of the Treg-associated marker FOXP3 was analyzed with multiplex real-time RT-PCR. Children with T1D showed both a low spontaneous (P < 0.05) and PHA-induced (P < 0.01) expression of FOXP3 mRNA compared to children with CD. Children with T1D also had a low PHA-induced FOXP3 mRNA expression compared to the group of children diagnosed with both T1D and CD (P < 0.05). Spontaneous (P < 0.05) and PHA-induced (P < 0.05) FOXP3 mRNA expression was high in children with CD compared to reference children. In contrast, stimulation with insulin tended to induce high FOXP3 mRNA expression in T1D children compared to reference children (P = 0.057). In conclusion, children with only T1D generally showed a lower FOXP3 mRNA expression than did children with CD, or with T1D in combination with CD, which suggests impaired regulation of the immune system in children with T1D.
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| 19. |
- Kultima, Kim, et al.
(författare)
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Development and evaluation of normalization methods for label-free relative quantification of endogenous peptides
- 2009
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Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 8:10, s. 2285-2295
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Tidskriftsartikel (refereegranskat)abstract
- The performances of 10 different normalization methods on data of endogenous brain peptides produced with label-free nano-LC-MS were evaluated. Data sets originating from three different species (mouse, rat, and Japanese quail), each consisting of 35-45 individual LC-MS analyses, were used in the study. Each sample set contained both technical and biological replicates, and the LC-MS analyses were performed in a randomized block fashion. Peptides in all three data sets were found to display LC-MS analysis order-dependent bias. Global normalization methods will only to some extent correct this type of bias. Only the novel normalization procedure RegrRun (linear regression followed by analysis order normalization) corrected for this type of bias. The RegrRun procedure performed the best of the normalization methods tested and decreased the median S.D. by 43% on average compared with raw data. This method also produced the smallest fraction of peptides with interblock differences while producing the largest fraction of differentially expressed peaks between treatment groups in all three data sets. Linear regression normalization (Regr) performed second best and decreased median S.D. by 38% on average compared with raw data. All other examined methods reduced median S.D. by 20-30% on average compared with raw data.
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| 20. |
- Ljungdahl, Anna, et al.
(författare)
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Imaging mass spectrometry reveals elevated nigral levels of dynorphin neuropeptides in L-DOPA-induced dyskinesia in rat model of Parkinson's disease.
- 2011
-
Ingår i: PloS one. - : Public Library of Science (PLoS). - 1932-6203. ; 6:9
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Tidskriftsartikel (refereegranskat)abstract
- L-DOPA-induced dyskinesia is a troublesome complication of L-DOPA pharmacotherapy of Parkinson's disease and has been associated with disturbed brain opioid transmission. However, so far the results of clinical and preclinical studies on the effects of opioids agonists and antagonists have been contradictory at best. Prodynorphin mRNA levels correlate well with the severity of dyskinesia in animal models of Parkinson's disease; however the identities of the actual neuroactive opioid effectors in their target basal ganglia output structures have not yet been determined. For the first time MALDI-TOF imaging mass spectrometry (IMS) was used for unbiased assessment and topographical elucidation of prodynorphin-derived peptides in the substantia nigra of a unilateral rat model of Parkinson's disease and L-DOPA induced dyskinesia. Nigral levels of dynorphin B and alpha-neoendorphin strongly correlated with the severity of dyskinesia. Even if dynorphin peptide levels were elevated in both the medial and lateral part of the substantia nigra, MALDI IMS analysis revealed that the most prominent changes were localized to the lateral part of the substantia nigra. MALDI IMS is advantageous compared with traditional molecular methods, such as radioimmunoassay, in that neither the molecular identity analyzed, nor the specific localization needs to be predetermined. Indeed, MALDI IMS revealed that the bioconverted metabolite leu-enkephalin-arg also correlated positively with severity of dyskinesia. Multiplexing DynB and leu-enkephalin-arg ion images revealed small (0.25 by 0.5 mm) nigral subregions with complementing ion intensities, indicating localized peptide release followed by bioconversion. The nigral dynorphins associated with L-DOPA-induced dyskinesia were not those with high affinity to kappa opioid receptors, but consisted of shorter peptides, mainly dynorphin B and alpha-neoendorphin that are known to bind and activate mu and delta opioid receptors. This suggests that mu and/or delta subtype-selective opioid receptor antagonists may be clinically relevant for reducing L-DOPA-induced dyskinesia in Parkinson's disease.
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| 21. |
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| 22. |
- Nilsson, Anna, et al.
(författare)
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Neuropeptidomics of mouse hypothalamus after imipramine treatment reveal somatostatin as a potential mediator of antidepressant effects
- 2012
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Ingår i: Neuropharmacology. - : Elsevier BV. - 0028-3908 .- 1873-7064. ; 62:1, s. 347-357
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Tidskriftsartikel (refereegranskat)abstract
- Excessive activation of the hypothalamic pituitary adrenal (HPA) axis has been associated with numerous diseases, including depression, and the tricyclic antidepressant imipramine has been shown to suppress activity of the HPA axis. Central hypothalamic control of the HPA axis is complex and involves a number of neuropeptides released from multiple hypothalamic subnuclei. The present study was therefore designed to determine the effects of imipramine administration on the mouse hypothalamus using a peptidomics approach. Among the factors found to be downregulated after acute (one day) or chronic (21 days) imipramine administration were peptides derived from secretogranin 1 (chromogranin B) as well as peptides derived from cerebellin precursors. In contrast, peptides SRIF-14 and SRIF-28 (1-11) derived from somatostatin (SRIF, somatotropin release inhibiting factor) were significantly upregulated by imipramine in the hypothalamus. Because diminished SRIF levels have long been known to occur in depression, a second part of the study investigated the roles of individual SRIF receptors in mediating potential antidepressant effects. SRA880, an antagonist of the somatostatin-1 autoreceptor (sst1) which positively modulates release of endogenous SRIF, was found to synergize with imipramine in causing antidepressant-like effects in the tail suspension test. Furthermore, chronic co-administration of SRA880 and imipramine synergistically increased BDNF mRNA expression in the cerebral cortex. Application of SRIF or L054264, an sst2 receptor agonist, but not 1,803807, an sst4 receptor agonist, increased phosphorylation of CaMKII and GluR1 in cerebrocortical slices. Our present experiments thus provide evidence for antidepressant-induced upregulation of SRIF in the brain, and strengthen the notion that augmented SRIF expression and signaling may counter depressive-like symptoms.
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| 23. |
- Nilsson, Anna, et al.
(författare)
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Striatal alterations of secretogranin-1, somatostatin, prodynorphin and cholecystokinin peptides in an experimental mouse model of Parkinson’s disease
- 2009
-
Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 8:5, s. 1094-1104
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Tidskriftsartikel (refereegranskat)abstract
- The principal causative pathology of Parkinson disease is the progressive degeneration of dopaminergic neurons in the substantia nigra pars compacta projecting to the striatum in the brain. The information regarding the expression of neuropeptides in parkinsonism is very limited. Here we have elucidated striatal neuropeptide mechanisms in experimental parkinsonism using the unilateral 6-hydroxydopamine model to degenerate dopamine neurons. A thoroughly controlled sample preparation technique together with a peptidomics approach and targeted neuropeptide sequence collections enabled sensitive detection, identification, and relative quantitation of a great number of endogenous neuropeptides. Previously not recognized alterations in neuropeptide levels were identified in the unilateral lesioned mice with or without subchronic 3,4-dihydroxy-L-phenylalanine administration, the conventional treatment of Parkinson disease. Several of these peptides originated from the same precursor such as secretogranin-1, somatostatin, prodynorphin, and cholecystokinin. Disease-related biotransformation of precursors into individual peptides was observed in the experimental model of Parkinson disease. Several previously unreported potentially biologically active peptides were also identified from the striatal samples. This study provides further evidence that neuropeptides take part in mediating the central nervous system failure associated with Parkinson disease.
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| 24. |
- Nilsson, Lennart, 1954-, et al.
(författare)
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Combinations of common chronic paediatric diseases deviate the immune response in diverging directions
- 2006
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Ingår i: Clinical and Experimental Immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 146:3, s. 433-442
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Tidskriftsartikel (refereegranskat)abstract
- The cytokine pattern of T lymphocytes has not been characterized in children with combinations of paediatric immunological disorders. We describe cytokine secretion in children with type 1 diabetes, coeliac disease and allergy and combinations of two of these diseases after stimulation with 'disease-specific' antigens. Peripheral blood mononuclear cells (PBMC) were collected from 68 children with type 1 diabetes, allergy or coeliac disease, two of these diseases in combination or none of these diseases. Using the enzyme-linked immunospot (ELISPOT) technique, interferon (IFN)-γ and interleukin (IL)-4 were analysed from fresh PBMC spontaneously and after in vitro stimulation with antigens associated with one or more of these diseases (insulin, gluten, birch and cat extract, β-lactoglobulin, ovalbumin and phytohaemagglutinin) in order to divide T helper (Th)1- from Th2-like lymphocytes. Stimulation with birch and cat extract caused increased IL-4 secretion in allergic children. A low IFN-γ response to insulin was found in type 1 diabetic children, whereas allergic children responded to insulin by increased IL-4 secretion. Children suffering from both type 1 diabetes (Th1-prone) and allergy (Th2-prone) reacted distinctly to general mitogen stimulation. Children suffering from two Th1-dominated diseases (type 1 diabetes and coeliac disease) showed hardly any response to either food or inhalation allergens. Our results indicate an important interplay between common immunological diseases in children. The combination of two Th1-deviated diseases is associated with a suppressed immune response, whereas a combination of Th1- and Th2-dominated diseases appears to increase the general immune response. © 2006 The Author(s).
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| 25. |
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| 26. |
- Scholz, Birger, et al.
(författare)
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Neuropeptidomic analysis of the embryonic Japanese quail diencephalon
- 2010
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Ingår i: BMC Developmental Biology. - 1471-213X. ; 10, s. 30-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Endogenous peptides such as neuropeptides are involved in numerous biological processes in the fully developed brain but very little is known about their role in brain development. Japanese quail is a commonly used bird model for studying sexual dimorphic brain development, especially adult male copulatory behavior in relation to manipulations of the embryonic endocrine system. This study uses a label-free liquid chromatography mass spectrometry approach to analyze the influence of age (embryonic days 12 vs 17), sex and embryonic day 3 ethinylestradiol exposure on the expression of multiple endogenous peptides in the developing diencephalon.Results: We identified a total of 65 peptides whereof 38 were sufficiently present in all groups for statistical analysis. Age was the most defining variable in the data and sex had the least impact. Most identified peptides were more highly expressed in embryonic day 17. The top candidates for EE2 exposure and sex effects were neuropeptide K (downregulated by EE2 in males and females), gastrin-releasing peptide (more highly expressed in control and EE2 exposed males) and gonadotropin-inhibiting hormone related protein 2 (more highly expressed in control males and displaying interaction effects between age and sex). We also report a new potential secretogranin-2 derived neuropeptide and previously unknown phosphorylations in the C-terminal flanking protachykinin 1 neuropeptide.Conclusions: This study is the first larger study on endogenous peptides in the developing brain and implies a previously unknown role for a number of neuropeptides in middle to late avian embryogenesis. It demonstrates the power of label-free liquid chromatography mass spectrometry to analyze the expression of multiple endogenous peptides and the potential to detect new putative peptide candidates in a developmental model.
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| 27. |
- Scholz, Birger, et al.
(författare)
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Striatal proteomic analysis suggests that first L-dopa dose equates to chronic exposure
- 2008
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 3:2, s. e1589-
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Tidskriftsartikel (refereegranskat)abstract
- L-3,4-dihydroxypheylalanine (L-dopa)-induced dyskinesia represent a debilitating complication of therapy for Parkinson's disease (PD) that result from a progressive sensitization through repeated L-dopa exposures. The MPTP macaque model was used to study the proteome in dopamine-depleted striatum with and without subsequent acute and chronic L-dopa treatment using two-dimensional difference in-gel electrophoresis (2D-DIGE) and mass spectrometry. The present data suggest that the dopamine-depleted striatum is so sensitive to de novo L-dopa treatment that the first ever administration alone would be able (i) to induce rapid post-translational modification-based proteomic changes that are specific to this first exposure and (ii), possibly, lead to irreversible protein level changes that would be not further modified by chronic L-dopa treatment. The apparent equivalence between first and chronic L-dopa administration suggests that priming would be the direct consequence of dopamine loss, the first L-dopa administrations only exacerbating the sensitization process but not inducing it.
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| 28. |
- Svensson, Marcus, et al.
(författare)
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Heat stabilization of the tissue proteome : a new technology for improved proteomics
- 2009
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Ingår i: Journal of Proteome Research. - : American Chemical Society (ACS). - 1535-3893 .- 1535-3907. ; 8:2, s. 974-981
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Tidskriftsartikel (refereegranskat)abstract
- After tissue or body fluid sampling, proteases and other protein-modifying enzymes can rapidly change composition of the proteome. As a direct consequence, analytical results will reflect a mix of in vivo proteome and ex vivo degradation products. Vital information about the presampling state may be destroyed or distorted, leading to variation between samples and incorrect conclusions. Sample stabilization and standardization of sample handling can reduce or eliminate this problem. Here, a novel tissue stabilization system which utilizes a combination of heat and pressure under vacuum was used to stop degradation in mouse brain tissue immediately after sampling. It was found by biochemical assays that enzymatic activity was reduced to background levels in stabilized samples. Western blot analysis confirmed that post-translational phosphorylations of analyzed proteins were stable and conserved for up to 2 h at room temperature and that peptide extracts were devoid of abundant protein degradation fragments. The combination of reduced complexity and proteolytic inactivation enabled mass spectrometric identification of several neuropeptides and endogenous peptides including modified species at higher levels compared to nonstabilized samples. The tissue stabilizing system ensures reproducible and rapid inactivation of enzymes. Therefore, the system provides a powerful improvement to proteomics by greatly reducing the complexity and dynamic range of the proteome in tissue samples and enables enhanced possibilities for discovery and analysis of clinically relevant protein/peptide biomarkers.
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| 29. |
- Svensson, Marcus, et al.
(författare)
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Neuropeptidomics : MS applied to the discovery of novel peptides from the brain
- 2007
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 79:1, s. 14-21
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Tidskriftsartikel (refereegranskat)abstract
- Peptidomics involves the comprehensive analysis of the peptide content of a certain cell, organ, body fluid, or organism. Per E. Andrén and colleagues at Uppsala University and the Karolinska Institutet (both in Sweden) describe neuropeptidomics approaches in brain lysates and tissue sections to study peptide expression in disease models and to identify potentially biologically active neuropeptides.
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| 30. |
- Svensson, Marcus, et al.
(författare)
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Neuropeptidomics : expanding proteomics downwards.
- 2007
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Ingår i: Biochemical Society Transactions. - 0300-5127 .- 1470-8752. ; 35:3, s. 588-593
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Tidskriftsartikel (refereegranskat)abstract
- Biological function is mainly carried out by a dynamic population of proteins and peptides which may be used as markers for disease diagnosis, prognosis and as a guide for effective treatment. The study of proteins is called proteomics and it is generally performed by two-dimensional gel electrophoresis and mass spectrometric methods. However, gel-based proteomics is methodologically restricted from the low mass region, which includes important endogenous peptides. The study of endogenous peptides, peptidomics, is complicated by protein fragments produced post-mortem during conventional sample handling. Nanoflow liquid chromatography and MS, together with improved methods for sample preparation, have been used to semi-quantitatively monitor endogenous peptides in brain tissue. When rapidly heat-denatured brain tissue was analysed, these methods enabled simultaneous detection of hundreds of peptides and the identification of several endogenous peptides not previously described in the literature. In an application of the MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) model for Parkinson's disease, the expression of the small protein PEP-19 was compared with controls. The levels were found to be significantly decreased in the striatum of MPTP-treated animals.
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| 31. |
- Tomičić, Sara, et al.
(författare)
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High levels of IgG4 antibodies to foods during infancy are associated with tolerance to corresponding foods later in life
- 2009
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Ingår i: Pediatric Allergy and Immunology. - : Wiley. - 0905-6157 .- 1399-3038. ; 5:1, s. 35-41
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Tidskriftsartikel (refereegranskat)abstract
- Children with eczema and sensitization to foods are recommended skin care and, if food allergy is proven by challenge, an elimination diet. For most children the diet period is transient, but the process behind tolerance development and the influence of decreased allergen exposure is not fully known. The aim of the study was to investigate the effect of elimination diet on serum and salivary antibodies and to identify immunological parameters related to the ability to tolerate foods. Eighty-nine children, below 2 yr of age, with eczema and suspected food allergy were included. Recommended treatment was skin care to all children, and 60 children had a period of elimination diet. At 4½ yr of age, the children were divided into two groups, based on if they had been able to introduce the eliminated foods, or not. Serum and salivary antibodies were analyzed with enzyme-linked immunosorbent assay and UniCAP® before and after a 6-wk treatment period and at 4½ yr of age. Children sensitized to egg and/or milk that could eat and drink the offending foods at 4½ yr of age, had higher levels of Immunoglobulin G4 antibodies to ovalbumin and β-lactoglobulin and also higher IgG4/Immunoglobulin E ratios on inclusion in the study, than those who had to eliminate egg and/or milk from their diet, beyond 4½ yr of age. The highest IgG4/IgE ratios were found in children with circulating IgE antibodies to egg and/or milk but negative skin prick test on inclusion. The 6-wk treatment period did not significantly affect the levels of serum and salivary antibodies. In conclusion, eczematous, food sensitized infants with high levels of IgG4 and high ratios of IgG4/IgE antibodies to food allergens are more likely to consume these foods at 4½ yr than infants with low levels and ratios.
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| 32. |
- Zdolsek, Helena, et al.
(författare)
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Reduced IL-2-induced IL-12 responsiveness in atopic children
- 2003
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Ingår i: Pediatric Allergy and Immunology. - : Wiley. - 0905-6157 .- 1399-3038. ; 14:5, s. 351-357
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Tidskriftsartikel (refereegranskat)abstract
- Atopy may be associated with a reduced T-cell function particularly regarding maturation of T helper 1 (Th1) responses. We hypothesized that atopic children may have a reduced capacity to up-regulate the β2 subunit of the interleukin-12 (IL-12) receptor (IL-12Rβ2, the signal-transducing component). The study included 38 children followed from birth to the age of 7 years. Twenty one had a cumulative history of atopic disease, whereas 17 had none. Sixteen out of 21 children also had atopic symptoms within the past year (current), out of whom 10 children had atopic airway symptoms. The expression of IL-12Rβ2 mRNA was analyzed by quantitative real-time PCR and the secretion of interferon-γ (IFN-γ), IL-5 and IL-10 was assessed by enzyme-linked immunosorbent assay (ELISA). Children with current atopic airway symptoms and high levels of total IgE up-regulated IL-12Rβ2 mRNA expression less than non-atopic children with low IgE levels after IL-2 stimulation. This was accompanied by a low IL-2- and IL-12-induced IFN-γ production, possibly reflecting the reduced capacity of atopic children to up-regulate the IL-12 receptor. As IL-2 is needed to initiate and sustain immune responses and IL-12 promotes Th1 responses, this may contribute to the Th2-skewed pattern in atopic children.
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