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AvaliaÃÃo de marcadores inflamatÃrios, da modulaÃÃo do sistema nervoso autonÃmico e de suas associaÃÃes na fragilidade de idososArnaldo Aires Peixoto JÃnior 23 May 2014 (has links)
nÃo hà / IntroduÃÃo: Sarcopenia, estado inflamaÃÃo crÃnica e diminuiÃÃo da modulaÃÃo autonÃmica cardÃaca sÃo frequentemente descritos em idosos frÃgeis. No entanto, o papel da inflamaÃÃo e diminuiÃÃo da modulaÃÃo autonÃmica em perda de massa muscular associada ao envelhecimento deve ser esclarecido. Objetivo: identificar, em idosos frÃgeis e robustos residentes na comunidade, correlaÃÃes entre alteraÃÃes autonÃmicas, nÃveis sÃricos de marcadores bioquÃmicos de inflamaÃÃo e diminuiÃÃo da forÃa e do desempenho muscular. Resultados: 98 voluntÃrios frÃgeis e robustos com idade de 60 anos ou mais foram submetidos à avaliaÃÃo clÃnica, exames laboratoriais e anÃlise da variabilidade da frequÃncia cardÃaca em decÃbito dorsal e em ortostase. O logaritmo natural do Ãndice de variabilidade da frequÃncia cardÃaca baixa frequÃncia (LF) foi inversamente relacionado com o marcador bioquÃmico da inflamaÃÃo fibrinogÃnio em idosos com fragilidade (p=0,046), mas nÃo em robustos. NÃo houve associaÃÃo entre Ãndices de variabilidade da frequÃncia cardÃaca e marcadores bioquÃmicos de inflamaÃÃo interleucina-6 e proteÃna C reativa ultrassensÃvel. Velocidade da marcha foi negativamente relacionada com o fibrinogÃnio em idosos frÃgeis (p=0,033), mas nÃo em idosos robustos. Em todos os idosos, velocidade da marcha foi negativamente relacionada com o fibrinogÃnio (p=0,017), interleucina-6 (p=0,038) e proteÃna C reativa ultrassensÃvel (p=0,010). ConclusÃo: nossos resultados sugerem que a sarcopenia relacionada inflamaÃÃo pode ser, pelo menos parcialmente, influenciada por diminuiÃÃo da modulaÃÃo autonÃmica em idosos. / Background: sarcopenia, chronic inflammation status and impairment of cardiac autonomic modulation are often described in frailty elderly. However, the role of inflammation and decreased autonomic modulation in loss of muscle mass associated with aging need to be enlightened. Aim: we aimed to identify, in community-dwelling frailty and robust elderly, correlations among autonomic changes, serum levels of biochemical markers of inflammation and decreased muscle strength and performance. Results: 98 volunteers aged 60 or older was assessed by clinical evaluation, laboratory tests and analysis of heart rate variability (HRV) in the supine and standing positions. The natural logarithm of the HRV index Low Frequency (LF) was inversely related with the biochemical marker of inflammation fibrinogen in frail elderly (p=0.049), but not in robust. There was no association between heart rate variability indices and biochemical markers of inflammation interleukin-6 and C-reactive protein high sensitivity. Gait speed was negatively correlated with fibrinogen in frail elderly (p=0.033), but not in elderly robust. In all elderly, gait speed correlated negatively with fibrinogen (p=0.017), IL-6 (p=0.038) and high-sensitivity CRP (p=0.010). Conclusion: our results suggest that inflammation-related sarcopenia can be at least partially influenced by decreased autonomic modulation in the elderly.
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Filogenia do processo inflamatório em animais ectotérmicos: estudo comparativo entre peixes teleósteos primitivos e modernos inoculados com BCG / Phylogeny of the inflammatory process in ectotermic animals: comparative study between primitive and modern telost fish inoculated with BCGRicardo Yuji Sado 03 September 2004 (has links)
O objetivo do presente estudo foi avaliar aspectos histológicos, imuno-histoquímicos e ultraestruturais da resposta inflamatória induzida experimentalmente, através da inoculação de BCG por via intramuscular em peixes filogeneticamente primitivos do gênero Arius sp e modernos do gênero Centropomus sp, com o intuito de estabelecer parâmetros comparativos da resposta inflamatória do ponto de vista filogenético entre peixes modernos e primitivos. Os resultados mostram haver diferenças na resposta inflamatória entre peixes modernos e primitivos; sendo que o primeiro tem capacidade de organização da lesão em granulomas típicos e células epitelióides secretoras de proteína S100 e citoqueratina, e que ao longo do experimento desenvolveu junções desmossômicas entre si; enquanto peixes primitivos não possuem capacidade de organização da lesão, não formando granulomas, apenas células gigantes secretoras de proteína S100. Não houve participação expressiva de células gigantes e pigmentares na resposta inflamatória no gênero Centropomus sp, sugerindo ser uma característica relacionada à espécie, contrariando alguns resultados verificados em peixes modernos no que diz respeito à participação de células pigmentares. / The aim of this study was the evaluation of the histological, imunohistochemical and ultra structural aspect of the inflammatory response experimentally induced by BCG intramuscular injection in phylogenetically primitive fishes of the genera Arius sp and modern of the genera Centropomus sp, with the purpose of establishing comparative parameters of the inflammatory response between modern and primitive fishes about phylogenetic aspect. The results show differences in the inflammatory response between modern and primitive fishes. Modern fishes have the ability of organization of the lesion, with development of tipical granulomas and epithelioid cells that produce S100 protein, cytokeratin and throughout the experiment they developed desmosomic junctions; instead of primitive fishes that don?t show the ability of organization of the lesion without forming an granuloma, just giant cells that produce S100 protein. It didn?t have an expressive participation of giant cells and pigmentcontaining cells in the inflammatory reaction in genera Centropomus sp, suggesting that It is a specie-specific characteristic, in opposition to some results found in modern fishes about pigment cells participation in the inflammatory reaction of modern fishes.
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Intracellular signaling mechanisms regulating the mast cell-mediated allergic inflammation.January 2007 (has links)
Ng Sin Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 120-135). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abbreviations --- p.iii / Abstract --- p.vi / 撮要 --- p.ix / Publications --- p.xi / Table of contents --- p.xiii / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Allergic Diseases and Allergic Inflammation --- p.1 / Chapter 1.1.1 --- Prevalence of Allergic Diseases --- p.1 / Chapter 1.1.2 --- Common Allergic Diseases: Allergic Asthma --- p.1 / Chapter 1.1.3 --- Common Allergic Diseases: Atopic Dermatitis --- p.2 / Chapter 1.1.4 --- Allergic Inflammation --- p.3 / Chapter 1.2 --- The Inflammatory Leukocytes: Mast Cells and Eosinophils --- p.6 / Chapter 1.2.1 --- Characteristics of Mast Cells --- p.6 / Chapter 1.2.2 --- Mast Cells Distribution --- p.8 / Chapter 1.2.3 --- Mast Cells Subtypes --- p.8 / Chapter 1.2.4 --- HMC-1 Cells --- p.9 / Chapter 1.2.5 --- Characteristics of Eosinophils --- p.12 / Chapter 1.3 --- Adhesion Molecules in Allergic Diseases --- p.15 / Chapter 1.3.1 --- Adhesion Molecules and Leukocyte Migration --- p.15 / Chapter 1.3.2 --- Selectin --- p.17 / Chapter 1.3.3 --- Intermolecular Adhesion Molecules --- p.17 / Chapter 1.3.4 --- Integrin --- p.18 / Chapter 1.4 --- Cytokines and Chemokines in Allergic Diseases --- p.18 / Chapter 1.4.1 --- IL-6 --- p.20 / Chapter 1.4.2 --- CXCL1 --- p.21 / Chapter 1.4.3 --- CXCL8 --- p.21 / Chapter 1.4.3 --- CCL2 --- p.22 / Chapter 1.5 --- Intercellular Signal Transduction Pathways in Inflammation --- p.24 / Chapter 1.5.1 --- RAS-RAF-mitogen-activated Protein Kinases --- p.24 / Chapter 1.5.2 --- Janus Kinase/ Signal Transducers and Activators of Transcriptions Pathway --- p.27 / Chapter 1.5.3 --- Nuclear Factor-KB Pathway --- p.29 / Chapter 1.5.4 --- Phosphoinositide 3-Kinase Pathway --- p.31 / Chapter 1.6 --- Aims and Scope of the Study --- p.33 / Chapter Chapter 2 --- Materials and Methods / Chapter 2.1 --- Materials --- p.35 / Chapter 2.1.1 --- HMC-1 Cell Line --- p.35 / Chapter 2.1.2 --- Human Buffer Coat --- p.35 / Chapter 2.1.3 --- Human Mast Cell Chymase and TLR ligands --- p.35 / Chapter 2.1.4 --- Media and Reagents for Cell Culture --- p.36 / Chapter 2.1.5 --- Reagents and Buffers for Purification of Human Eosinophils --- p.37 / Chapter 2.1.6 --- Reagents and Buffers for Flow Cytmetry --- p.38 / Chapter 2.1.7 --- Reagents and Buffers for Total RNA Extraction --- p.41 / Chapter 2.1.8 --- Reagents and Buffers for Reverse Transcription-Polymerase Chain Reaction (RT-PCR) --- p.42 / Chapter 2.1.9 --- Reagents and Buffers for Agarose Gel Electrophoresis --- p.45 / Chapter 2.1.10 --- Reagents and Buffers for Sodium Dodecyl Sulfate -polyacrylamide Gel Electrophoresis (SDS-PAGE) --- p.46 / Chapter 2.1.11 --- Reagents and Buffers for Western Blot Analysis --- p.48 / Chapter 2.1.12 --- Chemotactic Migration --- p.51 / Chapter 2.1.13 --- Signaling Transduction Inhibitors and Protein Synthesis Inhibitors --- p.51 / Chapter 2.2 --- Methods --- p.52 / Chapter 2.2.1 --- HMC-1 Cell Cultures --- p.52 / Chapter 2.2.2 --- Purification of Buffy Coat Eosinophils by MACS and Eosinophil Culture --- p.52 / Chapter 2.2.3 --- Total Cellular RNA Extraction --- p.53 / Chapter 2.2.4 --- RT-PCR --- p.54 / Chapter 2.2.5 --- Agarose Gel Electrophoresis --- p.55 / Chapter 2.2.6 --- Flow Cytometry Analysis --- p.55 / Chapter 2.2.7 --- Protein Array Analysis of Cytokine Release --- p.57 / Chapter 2.2.8 --- Quantitative Analysis ofCXCLl --- p.58 / Chapter 2.2.9 --- Total Protein Extraction --- p.58 / Chapter 2.2.10 --- SDS-PAGE --- p.58 / Chapter 2.2.11 --- Western Blot Analysis --- p.59 / Chapter 2.2.12 --- Chemotactic Migration Analysis --- p.60 / Chapter 2.2.13 --- Statistical Analysis --- p.60 / Chapter Chapter 3 --- Effects of Mast Cell Derived Chymase on Human Eosinophils and the Signaling Mechanisms: Implication in Allergic Inflammation / Chapter 3.1 --- Introduction --- p.61 / Chapter 3.2 --- Results --- p.65 / Chapter 3.2.1 --- Effects of Chymase on Eosinophil Survival --- p.65 / Chapter 3.2.2 --- Effects of Chymase on the Adhesion Molecule Expression of Eosinophils --- p.68 / Chapter 3.2.3 --- Effects of Chymase on the Chemokinetic Properties on Eosinophils --- p.71 / Chapter 3.2.4 --- Effects of Chymase on the Release of Chemokines and IL-6 from Eosinophils --- p.73 / Chapter 3.2.5 --- Signal Transduction Mechanism Involved in Regulating Chymase-induced Effects on Eosinophils --- p.78 / Chapter 3.3 --- Discussion --- p.71 / Chapter Chapter 4 --- TLR-mediated Effects and Signal Transduction Mechanism of HMC-1 Cells / Chapter 4.1 --- Introduction --- p.92 / Chapter 4.2 --- Results --- p.97 / Chapter 4.2.1 --- Expression of Adhesion Molecules on HMC-1 Cells --- p.95 / Chapter 4.2.2 --- TLR Expression Profile on HMC-1 Cells --- p.97 / Chapter 4.2.3 --- Effects of TLR ligands on HMC-1 Cell Adhesion Molecule Expressions --- p.99 / Chapter 4.2.4 --- TLR7-induced Phosphorylation of ERK and Effects of PD98059 on TLR7-induced ERK Phosphorylation --- p.104 / Chapter 4.2.5 --- Effect of TLR7 Ligand on HMC-1 Cells Cytokine Release --- p.108 / Chapter 4.3 --- Discussion --- p.110 / Chapter Chapter 5 --- Conclusions and Future Perspectives / Chapter 5.1 --- Conclusions --- p.115 / Chapter 5.2 --- Future Perspectives --- p.117 / References --- p.120 / Appendix --- p.136
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Control of Matrix Metalloproteinases in a Periodontitis Model: Molecules That Trigger or Inhibit MMP ProductionMatias Orozco, Catalina 01 December 2016 (has links)
In periodontitis, there is a disruption in the homeostasis of the oral microbiome by peridontopathogenic bacteria. However, while bacteria is essential for periodontitis to occur, the severity, pattern and progression of the disease is not solely determined by the microbial burden, and in fact has a lot to do with the overwhelming host inflammatory response. The response can vary even in two individuals with similar periodontopathogenic profiles. The host response leads to extracellular matrix (ECM) destruction, loss of attachment, alveolar bone resorption and eventually, edentulism. The host's reaction is orchestrated by proinflammatory cytokines and chemokines and matrix metalloproteinases (MMPs). MMPs are proteolytic enzymes capable of degrading collagen fibers from the extracellular matrix and are the main responsible for tissue damage and gingival recession in periodontitis. As a response to the limitations of the traditional therapies, new agents have been used in preclinical and clinical studies, namely host-modulatory agents, including anti-proteinase agents, anti-inflammatory agents and anti-resorptive agents. Focusing on changing the inflammatory process, as opposed to the microbial insult, can slow down the disease progression, improve clinical outcomes and even prevent tooth loss in severely compromised patients. This work examines the role of pro-inflammatory markers homocysteine in chronic inflammation and periodontitis. Homocysteine (Hcy) is a non-protein amino acid derived from the metabolism of the essential amino acid methionine via methyl group metabolism. Controlling Homocysteine as a potential inductor of MMPs, and hence of tissue destruction, can lead to new adjuvant therapies to improve clinical outcomes and prevent activation of the disease
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Activation microgliale : mécanismes et conséquences à long terme / Microglial activation : mechanisms and long term consequencesSigaut, Stéphanie 29 May 2017 (has links)
La neuro-inflammation induite par l'inflammation systémique ou générée en réponse à une lésion cérébrale aiguë a des conséquences cliniques néfastes : elle est mise en cause dans l'aggravation des lésions cérébrales aiguës chez l'homme, aussi bien chez l'adulte que chez l'enfant. La microglie est l'effecteur cérébral principal de cette réponse inflammatoire, et peut présenter selon les situations un profil neurotoxique ou, au contraire, anti-inflammatoire et régulateur. La compréhension des mécanismes d'activation microgliale et de leurs conséquences est capitale pour une meilleure prise en charge des malades. La première partie de ce travail de thèse s'intéresse aux conséquences de l'inflammation néonatale associée à la prématurité sur la réponse microgliale à l'âge adulte, face à de nouvelles agressions cérébrales que sont l'inflammation systémique et les lésions cérébrales aiguës. Dans un modèle murin d'inflammation néonatale, nous avons mis en évidence d'importantes modifications du transcriptome microglial une fois ces souris adultes. De plus, un stimulus inflammatoire à l'âge adulte modifie le profil d'activation microgliale, le pic des marqueurs pro-inflammatoires et immuno-régulateurs survenant plus précocement et intensément, démontrant l'existence d'une mémoire du système immunitaire inné cérébral. Ces modifications dans le profil d'activation microgliale s'accompagnent dans un modèle de lésion cérébrale excitotoxique d'une majoration de la taille des lésions de la substance blanche. Un traitement par mélatonine des souriceaux prévient cette aggravation. La deuxième partie de ce travail a consisté à caractériser in vitro le profil d'activation microgliale en réponse à une stimulation par HMGB1, une alarmine relarguée lors de la mort cellulaire et donc présente en cas de lésion cérébrale aiguë mais aussi de lésions extra-crâniennes associées. Nous avons montré que le profil d'activation microgliale dépend du type d'HMGB1 utilisé. Les microglies exposées à la forme recombinante de chez Sigma présentent un profil transcriptomique proinflammatoire mais une baisse des taux de cytokines sécrétées dans le milieu. Ces résultats mettent en évidence l'importance de l'inflammation et de l'activation microgliale dans le pronostic des lésions cérébrales et offrent la possibilité de mettre en place des stratégies neuroprotectrices innovantes / Neuroinflammation induced by systemic inflammation or generated in response to acute brain injury has adverse clinical consequences: it is implicated in exacerbation of acute brain injury in humans, for adults as well as for children. Microglia is the main effector of this cerebral inflammatory response, and may present, depending on the situation, a neurotoxic or - on the opposite - anti-inflammatory and regulating profile. To decipher the mechanisms of microglial activation and their consequences is essential for better management of patients.The first part of this thesis focuses on the consequences of neonatal inflammation associated with prematurity on the microglial response in adulthood, in case of new cerebral aggressions such as systemic inflammation or acute brain injury. Relying on a mouse model of inflammation of the preterm infant, we have demonstrated drastic modifications of the microglial transcriptome once these mice are adults. Moreover, when an inflammatory stimulus occurs in adulthood, the microglial activation profile is altered, the peak of pro-inflammatory and immuno-regulatory markers occurring earlier, demonstrating the existence of a memory of the cerebral innate immune system. These changes in the microglial activation profile are accompanied in a model of excitotoxic brain injury by an increase of the white matter lesion size. Melatonin treatment of mice prevents the happening of this worse outcome. In the second part of this thesis, we characterized the microglial activation profile in vitro, in response to stimulation by HMGB1, a damage associated molecular pattern released during cell death and therefore present in acute brain injuries but also in associated extra-cranial injuries. We have shown that the microglial activation profile depends of the kind of HMGB1 used. Microglia exposed to Sigma recombinant form have a proinflammatory transcriptomic profile but a lower release of cytokines in the culture medium. These results highlight the importance of inflammation and microglial activation in the prognosis of brain injuries and offer the opportunity to implement innovative neuroprotective strategies
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Whole exome analysis of individuals and families with chronic recurrent multifocal osteomyelitis (CRMO)Cox, Allison Jeanne 01 December 2016 (has links)
Chronic recurrent multifocal osteomyelitis (CRMO) is a rare, pediatric, autoinflammatory disease characterized by bone pain due to sterile osteomyelitis, and is often accompanied by psoriasis or inflammatory bowel disease. There are two syndromic forms of CRMO, Majeed syndrome and DIRA, for which the genetic cause is known. However, for the majority of cases, the genetic basis is unknown. Via whole-exome sequencing and linkage analysis, we determined the most likely causative mutations in four families. While the mutations are in three different genes – FBLIM1, PLCG2 and PIP; all three genes are involved in Fcγ signaling and osteoclast activation.
In a large cohort of 61 individuals with CRMO, we performed gene and pathway based association analysis using the 1000 genomes participants of European ancestry as controls. One gene from the family-based analyses, ANO6, was significantly enriched for rare variants in our cohort of cases. ANO6 is involved in P2RX7- mediated inflammasome activation and in the regulation of bone mineralization. While no pathways were enriched for rare variants in the CRMO cohort after genome-wide correction, four pathways were significantly enriched for rare variants in the control samples, indicating a protective effect of the variants. The second most significant pathway, activation of chaperone genes by XBP1s, is relevant to CRMO pathogenesis as XBP1s is a transcription factor that attenuates ER stress, and regulates the expression of genes involved in RANKL signaling and bone remodeling.
An association analysis using a larger set of cases followed by functional validation of candidate genes is necessary to confidently declare the mutations isolated in the work presented here to be pathogenic. Our preliminary findings suggest that mutations in genes involved in both the inflammatory response and bone remodeling underlie the pathogenesis of CRMO.
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Periodontal therapy Improves Oral and Gut Microbiota and Reduces Systemic Inflammation and Endotoxemia in Patients with CirrhosisMatin, Payam 01 January 2018 (has links)
Objectives: The aim of this pilot study was to compare the changes in oral and gut microbiota, endotoxemia, and systemic and local inflammatory markers following oral interventions in subjects with and without cirrhosis.
Methods: Study subjects displaying gingivitis or mild/moderate periodontitis were placed into two groups: with cirrhosis (n= 24) and without cirrhosis (n=21). Each subject received nonsurgical periodontal therapy. Serum, stool and saliva samples were collected prior to and 30 days post-therapy and analyzed for stool/saliva microbiome, MELD score, endotoxin and IL-6 levels.
Results: There was no difference in age, gender and the periodontal disease status between groups. At day 30 post therapy, there was a significant reduction in MELD score, endotoxin levels, IL-6 levels and oral and stool microbiome dysbiosis in cirrhotic patients.
Conclusion: Endotoxemia and systemic inflammation can be reduced following periodontal therapy, which is likely due to improvement in oral-origin microbiota in both saliva and stool in cirrhotic patients.
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Molecular basis of Nod1 And Nod2 signalingVer Heul, Aaron Martin 01 May 2013 (has links)
NOD1 and NOD2 (nucleotide-binding oligomerization domain-containing proteins 1 and 2) are related innate immune receptors responsible for initiating a response to bacterial infection. They belong to a class of receptors known as Pattern Recognition Receptors (PRRs), which are germline encoded immune receptors that mediate various innate immune responses. These receptors recognize conserved microbial motifs known as Pathogen-Associated Molecular Patterns (PAMPs). The PRR-PAMP paradigm forms the bedrock of how innate immunity is understood today. As two of the first intracellular PRRs discovered, NOD1 and NOD2 came to define an entire subclass of PRRs, the NOD-like receptors (NLRs). PRRs relay their signals through protein:protein interaction motifs that typically adopt a characteristic Death Domain (DD) fold. NOD1 and NOD2 signal through their respective CAspase Recruitment Domains (CARDs), which are part of a DD subfamily. The CARDs of NOD1 and NOD2 interact with multiple downstream effectors and are thus situated at a key point for regulation and coordination of NOD1 and NOD2 signaling.
To better understand this regulation, I structurally and functionally characterized interactions made by the CARDs of NOD1 and NOD2. Receptor Interacting Protein kinase 2 (RIP2) is an effector of both NOD1 and NOD2 that activates the NF-ΚB pathway to elicit an inflammatory response. I discovered a new binding interaction between the CARDs of NOD1 and NOD2 and ubiquitin. Furthermore, I elucidated a role for this interaction by showing that ubiquitin binds NOD1 and NOD2 CARDs competitively with the CARD of RIP2. Through biophysical and biochemical investigation, I identified mutants of NOD1 CARD that did not bind ubiquitin and were thus insensitive to its competitive effect on RIP2 binding. Utilizing this mutant in functional studies defined ubiquitin as a negative regulator of NOD1 signaling. Characterizing NOD1 allowed rational design of mutations that uncovered a similar role for ubiquitin in the NOD2 pathway. This introduces the potential for broader application of these findings in other DD-mediated pathways.
NOD1 and NOD2 also bind the autophagy protein ATG16L. I investigated the molecular mechanisms of this interaction and found that NOD1 and NOD2 bind ATG16L through their CARDs. I also found that the domain on ATG16L responsible for binding NOD1 and NOD2 is the C-terminal WD40 Β-propeller. Furthermore, the CARD:Β-propeller interaction is sufficient to mediate interaction between NOD1 or NOD2 and ATG16L. The finding that the ATG16L Β-propeller also binds ubiquitin leaves open the possibility that ubiquitin regulates pathway selection by NOD1 and NOD2.
Together, these studies advance our understanding of NOD1 and NOD2 signaling and lay the groundwork for further mechanistic investigations into coordination of inflammatory and autophagic signaling pathways by the immune system in general.
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The role of complement component C5a in nociceptive sensitizationWarwick, Charles A. 01 May 2017 (has links)
The complement system is a principal component of innate immunity. Recent studies have underscored the importance of C5a and other complement components in inflammatory and neuropathic pain, although the underlying mechanisms are largely unknown. In particular, it is unclear how the complement system communicates with nociceptors and which ion channels and receptors are involved. Here we demonstrate that inflammatory thermal and mechanical hyperalgesia induced by complete Freund’s adjuvant were accompanied by C5a upregulation and were markedly reduced by C5a receptor (C5aR1) knockout (KO) or treatment with the C5aR1 antagonist PMX53. Direct administration of C5a into the mouse hindpaw produced strong thermal and mechanical hyperalgesia, an effect that was absent in TRPV1 KO mice, and was blocked by the TRPV1 antagonist AMG9810. Immunohistochemistry of mouse plantar skin showed prominent expression of C5aR1 in macrophages. Additionally, C5a evoked strong Ca2+ mobilization in macrophages. Macrophage depletion in transgenic macrophage Fas-induced apoptosis (MAFIA) mice abolished C5a-dependent thermal and mechanical hyperalgesia. Examination of inflammatory mediators following C5a injection revealed a rapid upregulation of nerve growth factor (NGF), a mediator known to sensitize TRPV1. Pre-injection of an NGF-neutralizing antibody or Trk inhibitor GNF-5837 prevented C5a-induced thermal hyperalgesia. Notably, NGF-induced thermal hyperalgesia was unaffected by macrophage depletion. Collectively, these results suggest that C5a induces thermal and mechanical hyperalgesia by triggering macrophage-dependent signaling that involves mobilization of NGF and NGF-dependent sensitization of TRPV1. Our findings highlight the importance of macrophage-to-neuron signaling in pain processing and identify C5a, NGF and TRPV1 as key players in this cross-cellular communication.
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Die Rolle von Progranulin in der bipolar-affektiven Störung / Progranulin plasma levels and genotypes in bipolar disorder patientsWeigl, Johannes January 2013 (has links) (PDF)
Durch Messung der Progranulinspiegel im Blutplasma mittels ELISA konnte in vorliegender Arbeit ein signifikanter Unterschied zwischen bipolaren Patienten und
Kontrollen nachgewiesen werden. Dabei wies das Patientenkollektiv durchschnittlich niedrigere Konzentrationen auf. Befunde vorausgegangener Studien deuten darauf hin, dass ein peripherer Progranulinmangel auch mit zentralnervösen Veränderungen einhergehen kann und somit einen Anteil an der Pathophysiologie der bipolaren Störung haben könnte. Insbesondere eine immunologisch-entzündliche Dysregulation sowie
fehlende neurotrophe Impulse könnten dabei eine wesentliche Rolle spielen.
Überdies fiel bei der Auswertung der Daten eine hochsignifikante Korrelation zwischen Progranulinspiegel und Lebensalter der Probanden auf. Dabei nahm mit steigendem Alter auch die periphere Progranulinkonzentration zu, was im Zuge des physiologischen Alterungsprozesses oder aber auch als Folge von neurodegenerativen bzw. -
inflammatorischen Vorgängen auftreten könnte.
Bei der molekulargenetischen Untersuchung der Polymorphismen rs2879096, rs4792938 und rs5848 konnten keine signifikanten Unterschiede in der Genotypen- und
Haplotypenverteilung zwischen Patienten und Kontrollen gefunden werden, was sich möglicherweise auf die relativ kleine Stichprobe von 181 Probanden zurückführen lässt.
Zumindest existieren Hinweise auf eine Rolle der jeweiligen Polymorphismen bei verschiedenen neuropsychiatrischen Erkrankungen, möglicherweise auch bei der bipolaren Störung.
Außerdem fand sich bei den im Progranulingen liegenden SNPs rs2879096 und rs4792938 keine Assoziation einer Risikogenvariante zu veränderten Progranulinspiegeln, das heißt keiner der beiden Polymorphismen scheint funktionelle Bedeutung zu haben. Somit ließe sich kein Effekt des Genotyps auf die periphere Progranulinkonzentration nachweisen, wobei wiederum die verhältnismäßig niedrigen Fallzahlen beachtet werden müssen.
Der in der 3’UTR liegende SNP rs5848 scheint hingegen im Patientenkollektiv zu deutlich erniedrigten Proteinspiegeln zu führen. Dieser Befund steht auch im Einklang 47 mit einer Vielzahl von Studien, die rs5848 eine Bedeutung bei verschiedenen neuropsychiatrischen Erkrankungen beimessen und unterstreicht die Rolle niedriger Progranulinkonzentrationen in der bipolaren Störung.
Zusammenfassend lässt sich feststellen, dass bei bipolaren Patienten signifikant niedrigere Progranulinkonzentrationen als in der Kontrollgruppe gemessen wurden.
Weitere Studien, welche die zu Grunde liegenden biochemischen Vorgänge und Pathomechanismen erforschen, wären nun von Interesse, um ein besseres Verständnis
der Erkrankung zu erlangen. Langfristig wäre die Nutzung des Progranulinspiegels als diagnostisches Werkzeug erstrebenswert, wobei sich dies auf Grund des großen
Overlaps zwischen Patienten- und Kontrollgruppe wohl eher schwierig gestalten wird.
Die relativ unkomplizierte Progranulinbestimmung im Blutplasma könnte möglicherweise im Rahmen einer Messung vieler verschiedener Parameter als Baustein eines diagnostischen Apparates zur Erkennung der bipolaren affektiven Störung dienen. Somit wären weiterführende Untersuchungen anhand größerer Fallzahlen und
funktionelle Studien der pathomechanistischen Zusammenhänge des Progranulins ein interessantes Feld, um einige der zahlreichen ungeklärten Fragen rund um die bipolare Störung weiter aufzuklären. / Subject: Progranulin plasma levels and genotypes in bipolar disorder patients
Methods: ELISA of progranulin and genotyping of 3 SNPs in patients and healthy controls
Results: Progranulin plasma levels werde significantly reduced in bipolar patients. Progranulin levels were significantly higher with increased age in patients and healthy controls.
Conclusions: Progranulin as an inflammatory biomarker could be involved in the pathogenesis of bipolar disorder, at least in a subgroup of patients
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