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Envolvimento de mediadores inflamatórios na hiperalgesia muscular induzida por contração isométrica sustentada em ratos / The inflammatory mechanisms involved in mechanical muscle hyperalgesia induced by susteined isometric contraction in ratsMelo, Bruna de, 1987- 25 August 2018 (has links)
Orientador: Maria Cláudia Gonçalves de Oliveira Fusaro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Aplicadas / Made available in DSpace on 2018-08-25T13:05:07Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: Estudos demonstram que a dor muscular induzida por contração isométrica sustentada (CIS) possui importante impacto socioeconômico, no entanto, apesar de sua relevância clínica, os mecanismos inflamatórios envolvidos no desenvolvimento desse tipo de dor ainda são pouco compreendidos. O objetivo deste estudo foi analisar os mecanismos inflamatórios envolvidos no desenvolvimento desse tipo de hiperalgesia muscular. Para isso foi utilizado o modelo de hiperalgesia muscular induzido por contração isométrica sustentada, recentemente desenvolvido por nosso grupo de pesquisa, que consiste na indução de contração muscular isométrica no músculo gastrocnêmio de ratos machos Wistar, pesando entre 200 e 250g, que receberam uma corrente elétrica através do equipamento da marca Grass, modelo SX88R, corrente monofásica, pulso repetido, frequência de 50Hz, duração de pulso de 19ms através de eletrodos tipo agulha, pelo período de 1 hora. Para traçar o perfil inflamatório deste modelo foram administrados via intramuscular, 5 minutos, antes da contração isométrica as seguintes drogas: DALB K (3;30'mu'g) e Bradizida (1,5;15 'mu'g)(antagonistas dos receptores de bradicinina B1 e B2, respectivamente), Atenolol (0,6; 6'mu'g) e ICI 118551(0,15;1,5'mu'g) (antagonistas dos receptores adrenérgicos 'beta'1 e 'beta', respectivamente), Indometacina, uma hora antes (10;100'mu'g) (inibidor não seletivo das cicloxigenases) e A317491 (0,6; 6; 60 'mug) (antagonista seletivo dos receptores P2X3 e P2X2/3); e administrado intraperitoneal, 20 minutos antes, a Fucoidina (25mg/Kg) (inibidora da ação das selectinas). Os resultados demonstraram que todos esses antagonistas e inibidores reduziram significativamente a hiperalgesia muscular induzida pela contração isométrica sustentada, confirmando o envolvimento da bradicinina, aminas simpatomiméticas, prostaglandinas, neutrófilos e do ATP endógeno via receptores P2X3 e P2X2/3 na hiperalgesia muscular induzida pela contração isométrica sustentada. Esses resultados delineiam pela primeira vez o perfil inflamatório da hiperalgesia muscular induzida por contração isométrica sustentada e sugerem importantes alvos terapêuticos para estudo e tratamento da dor muscular, além de abrir novas perspectivas de estudo de outros mecanismos importantes no desenvolvimento da mesma / Abstract: Studies show that muscle pain induced by sustained isometric contraction (CIS) have an important socioeconomic impact, however, despite their clinical relevance, the inflammatory mechanisms involved in the development of this type of pain are still poorly understood. The aim of this study was to analyze the inflammatory mechanisms involved in the development of this type of muscle hyperalgesia. For this model of muscle hyperalgesia induced by sustained isometric contraction, recently developed by our research group, which consists of the induction of isometric muscle contraction in the gastrocnemius muscle of male Wistar rats were used, weighing between 200 and 250g, receiving an electric current through the equipment brand Grass , model SX88R , single phase , repeated pulse frequency of 50 Hz , pulse duration of 19ms via needle-like electrodes for a period of 1 hour. To trace the inflammatory profile of this model, the following drugs were administered intramuscularly 5 minutes before the isometric contraction: DALB K (3; 30'mu'g) and Bradizyde (1.5, 15 mg) (antagonists of bradykinin B1 and B2 receptors, respectively), Atenolol (0.6 ; 6'mu'g) and ICI 118551 (0.15, 1.5 mg) ('beta1 and 'beta'2 adrenergic receptor antagonists, respectively), indomethacin (10 ; 100'mu'g ) ( inhibitory action of cyclooxygenase ) and A317491 ( 0.6 , 6, 60 mg) (selective antagonist of P2X3 and P2X2 / 3 receptors) , and administered intraperitoneally 20 minutes before the fucoidin ( 25mg/Kg ) ( inhibitory action of selectins) . The results showed that all of these antagonists and inhibitors significantly reduced muscular hyperalgesia induced by sustained isometric contraction, confirming the involvement of bradykinin, sympathomimetic amines, prostaglandins, neutrophils and endogenous ATP via P2X3 and P2X2/3 receptors in muscle hyperalgesia induced by isometric contraction sustained. These results delineate first the inflammatory profile of muscle hyperalgesia induced by sustained isometric contraction and suggest important targets for study and treatment of muscle pain, and open new perspectives for the study of other important mechanisms in the development of the same / Mestrado / Biodinâmica do Movimento Humano e Esporte / Mestra em Ciências da Nutrição e do Esporte e Metabolismo
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Avaliação da atividade farmacológica de extrato bruto diclorometânico das folhas de Piper umbellatum microencapsulado e livre padronizado em 4-nerolidilcatecol / Pharmacological activity evoluation of microencapsulated and free crude dichloromethane extract from leaves of Piper umbellatum standardized in 4-nerolidylcatecholIwamoto, Leilane Hespporte, 1985 26 August 2018 (has links)
Orientadores: Rodney Alexandre Ferreira Rodrigues, Mary Ann Foglio, João Ernesto de Carvalho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T07:27:17Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: A espécie Piper umbellatum L., sinonímia Pothomorphe umbellata (L.) Miquel, é conhecida popularmente como pariparoba, caapeba e malvarisco. Tendo em vista as diferentes atividades biológicas comprovadas para a espécie Piper umbellatum e a técnica de microencapsulação por Spray Dryer, o objetivo desse trabalho foi avaliar a atividade farmacológica de extrato bruto padronizado (EBP) de P. umbellatum em modelos de câncer, inflamação, úlcera e verificar se as micropartículas de EBP apresentam atividade antiproliferativa in vitro. O extrato bruto diclorometânico de P. umbellatum possui 23,9% de 4-nerolidilcatecol aproximadamente. Foi avaliado a sua atividade anticâncer em modelo in vivo de tumor sólido de Ehrlich, atividade anti-inflamatória no edema da pata induzido por carragenina e peritonite. EBP foi capaz de reduzir o crescimento do tumor, quando administrado diariamente por via oral, sem sinais de toxicidade. Além disso, diminuiu o edema de pata e a migração de leucócitos no modelo de peritonite dessa forma, acredita-se existir uma relação entre a atividade anticâncer e anti-inflamatória. Também foi comprovada sua a atividade antiulcerogênica e gastroprotetora, relatada pelo uso popular no tratamento de úlceras gástricas. Os mecanismo de ação gastroprotetor envolvido na manutenção dos grupos sulfidrílicos, aumento de glutationa e de muco relacionam sua atividade antiulcerogênica à atividade antioxidante já descrita na literatura. O processo de microencapsulação por Spray Dryer do extrato bruto diclorometânico de P. umbellatum com o amido modificado Purity Gum 1773® permitiu alterar a propriedade graxa inerente a este extrato, insolúvel em água e foi capaz de manter sua atividade antiproliferativa in vitro. Dessa forma, a técnica de Spray Dryer pode ser um caminho para desenvolver um extrato seco de P. umbellatum. Portanto, podemos concluir que P. umbellatum pode ser fonte promissora para o desenvolvimento de novos agentes terapêuticos, tanto para o tratamento de úlceras gástricas quanto para inflamação e câncer / Abstract: The species Piper umbellatum, is popularly known as "pariparoba", "caapeba" and "malvarisco". Despite the different biological activities certified for the species P. umbellatum and the technique of microencapsulation by Spray Dryer, the aim of this study was to evaluate the pharmacological activity of dichloromethane crude extract (DCE) from Piper umbellatum leaves in models of cancer, inflammation and gastric ulcer and also evaluate the antiproliferative activity of microparticles containing standardized crude extract (SDE) in a panel of human tumor cell lines. The SDE from P. umbellatum containing 23,9% of 4-nerolidylcatechol approximately and its in vivo anticancer activity in the Ehrlich solid tumor model as well as its anti-inflammatory activity on carrageenan induced paw edema and peritonitis. The SDE presented in vitro and in vivo antiproliferative activity, being capable to reduce tumor growth when administered daily by oral route, without signals of toxicity. It was also reduced paw edema induced and leukocyte migration on carrageenan induced peritonitis model. Thus establishing a relationship between the anticancer and anti-inflammatory activities.It was also confirmed the popular use of P. umbellatum in the treatment of gastric ulcers, as SDE presented gastroprotective action dependent of the sulfhydryl groups, increase glutatione and mucus pathway and possibly for its antioxidant potential. The microencapsulation process by Spray Dryer of SDE of P. umbellatum with modified starch (Purity Gum 1773®) allowed improvement of the extract solubility, without interfere on its in vitro antiproliferative activity. Thus, the technique of Spray Dryer may be a good alternative to the development of a dry extract of P. umbellatum. Therefore, we conclude that P. umbellatum is a promising source for the development of new therapeutic agents for the treatment gastric ulcers, inflammation and cancer / Mestrado / Farmacologia, Anestesiologia e Terapeutica / Mestra em Odontologia
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Efeito dos antiinflamatórios tópicos acetato de prednisolona 1%, nepafenaco 0.1% e cetorolaco de trometamina 0.4% na manutenção da midríase intra-operatória em facectomias = estudo clínico aleatorizado / Effect of preopertaive use of topical prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery : a randomized trialZanetti, Fernando Roberte, 1983- 19 August 2018 (has links)
Orientadores: Rodrigo Pessoa Cavalcanti Lira, Carlos Eduardo Leite Arieta / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T07:57:39Z (GMT). No. of bitstreams: 1
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Previous issue date: 2011 / Resumo: Introdução: Os Antiinflamatórios tópicos são utilizados comumente no tratamento da inflamação ocular e do edema macular cistóide relacionado a cirurgia de catarata. Tem sido sugerido o uso de antiinflamatórios antes da cirurgia, para conseguir uma melhor midriase intraoperatória. Foi relatado que quando midriase e maior do que 6 mm, a incidência de ruptura da cápsula posterior e reduzido pela metade. O objetivo deste estudo original foi comparar o efeito do uso pré-operatório do acetato de prednisolona, do cetorolaco de trometamina, do nepafenaco e de um placebo, na manutenção da midriase intra-operatória da cirurgia de catarata. Objetivo: Comparar o efeito do uso pré-operatório dos antiinflamatórios tópicos acetato de prednisolona 1%, nepafenaco 0.1% e cetorolaco de trometamina 0.4%, alem de um placebo, na manutenção da midriase intraoperatoria durante a cirurgia de catarata. Desenho: Ensaio clinico aleatorizado, mascarado, realizado em um único centro. Métodos: E um estudo composto por 140 pacientes submetidos a cirurgia de facoemulsificação de catarata. Os pacientes (35 voluntários por grupo) foram aleatorizados para receber o placebo (carboximetilcelulose de sódio 0,5%), acetato de prednisolona 1%, cetorolaco de trometamina 0,4% e o nepafenaco 0,1%. Os colírios eram administrados 3 vezes ao dia e iniciados 48 horas antes da cirurgia.. A medida do tamanho da pupila foi realizada pelo cirurgião usando um compasso nos seguintes momentos: antes da secção da córnea e ao final da cirurgia. O desfecho primário foi avaliar a eficácia de cada medicamento em inibir a miose intraoperatoria (pupilas > 6mm, no final da cirurgia). O desfecho secundário foi obter pupilas > 6mm no inicio da cirurgia. Resultados: O numero de pacientes no grupo da prednisolona (29/35), no grupo do nepafenaco (31/35) e no grupo do cetorolaco (30/35) com diâmetro pupilar > 6 mm foi maior do que no grupo placebo em relação a manutenção da midriase intraoperatoria (19/35 - P =. 003). Não houve diferença estatística entre o grupo da prednisolona, do nepafenaco e do cetorolaco na manutenção da midriase intraoperatória (P =. 791). Não houve complicações durante a cirurgia ou efeitos adversos relacionados com o uso pré-operatório do colírio. Conclusão: O uso pré-operatório da prednisolona, do cetorolaco e do nepafenaco foi eficaz na manutenção midriase intraoperatória quando comparado com o placebo / Abstract: Introduction: Topical anti-inflammatory drugs are commonly used in the management of ocular inflammation and cystoid macular edema related to cataract surgery. It has been suggested the use of anti-inflammatory drugs before surgery, to achieve better intraoperative mydriasis. It was reported that, when mydriasis is greater than 6 mm, the incidence of posterior capsule rupture is reduced by half. The objective of the original study was to compare the effect of preoperative use of topical anti-inflammatory prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, in the maintenance of intraoperative mydriasis in cataract surgery. Purpose: To compare the effects of preoperative use of topical anti-inflammatory prednisolone acetate, ketorolac tromethamine, nepafenac and placebo, on the maintenance of intraoperative mydriasis during cataract surgery. Design: Randomized clinical trial, single-center and masked. Methods: This study comprised 140 patients scheduled for cataract surgery. Patients (35 in each group) were randomized to receive placebo, prednisolone acetate, ketorolac tromethamine 0.4 % or nepafenac. These eye drops were administered three times daily for the two days prior to surgery. The pupillary diameters were measured by the surgeon using a compass prior to the corneal section and at the end of surgery. The primary outcome was the number of patients with pupil > 6 mm at the end of the surgery; the secondary outcome was the number of patients with pupil > 6 mm at the beginning of the surgery. Results: All the patients achieved pupil > 6 mm at the beginning of the surgery. The number of patients in the prednisolone (29/35), nepafenac (31/35) and ketorolac (30/35) groups with pupil > 6 mm was greater than in the placebo group in the maintenance of intraoperative mydriasis (19/35 - P =.003 - Table 2). There was no statistical difference among the prednisolone, nepafenac and ketorolac groups in the maintenance of intraoperative mydriasis (P =.791). There were no complications during surgery or related to the preoperative use of the eye drops. Conclusion: Preoperative use of ketorolac, prednisolone and nepafenac was effective in maintaining intraoperative mydriasis when compared with placebo / Mestrado / Oftalmologia / Mestre em Ciências Médicas
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Investigating the role of iASPP in skin homeostasis and tumourigenesisChung, Ho Ki Kathryn January 2014 (has links)
No description available.
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Conception d'un produit alimentaire aux propriétés santé constantes basée sur la caractérisation des effets positifs sur la sphère digestive d'une matrice naturellement riche en lysozyme : le lait d'ânesseYvon, Sophie 01 December 2017 (has links) (PDF)
Les pathologies intestinales sont des maladies multifactorielles dont l’incidence ne cesse d’augmenter. Les maladies organiques regroupent les maladies inflammatoires chroniques de l'intestin tel que la maladie de Crohn (MC) et les pathologies fonctionnelles digestives comprennent les différentes formes du syndrome de l'intestin irritable (SII). Ces pathologies présentes des caractéristiques communes comme des troubles du transit, des douleurs abdominales, un dysfonctionnement de la barrière intestinale et des modifications de la communication bidirectionnelle de l’axe intestin-cerveau et une altération de la composition du microbiote intestinal (dysbiose). Cette dernière peut être en partie associée à un déficit de production en peptides et protéines antimicrobiennes (PAMs) par les cellules de Paneth. Parmi les cibles thérapeutiques stratégiques, une réduction de la dysbiose dans le but de réduire l’état inflammatoire ou micro-inflammatoire de la muqueuse font aujourd’hui l’objet de différentes études. Ces traitements alternatifs montrent l’efficacité d’un régime nutritionnel adapté, d’un apport en probiotiques ou en prébiotiques sur le microbiote intestinal des patients MC et SII, et sur l’intégrité de leur barrière intestinale. Parmi les matrices alimentaires présentant une composition nutritionnelle intéressante proche du lait maternel humain, le lait d’ânesse (LA) contient également une forte teneur en PAMs (lysozyme). En parallèle, un observatoire économique et social de la filière asine commandité par l’Institut National Âne et Mulet fait le diagnostic d’une activité grandissante autour du LA chez les éleveurs français et montre, face à une concurrence italienne et chinoise importante, la nécessité d’une meilleure organisation de la filière via une meilleure valorisation du LA. L’objectif de cette thèse était d’évaluer un potentiel effet santé du LA et d’apporter des preuves scientifiques robustes pour permettre une meilleure valorisation de ce dernier. Ainsi, l’effet d’une consommation orale chronique de LA a été évalué sur deux modèles précliniques murins distincts : un modèle d’iléite expérimentale induite par une administration per os d’indométacine et un modèle de stress psychologique chronique (Water Avoidance Stress, WAS). Dans ce travail, le rôle clé de l’activité du lysozyme dans les effets observés a également été évalué. Des essais de traitements thermiques ont aussi été réalisés pour optimiser un barème de pasteurisation permettant de proposer un LA répondant aux normes réglementaires microbiologiques et sanitaires tout en conservant l’activité du lysozyme contenue dans le lait. Les travaux de cette thèse montrent que le LA possède des propriétés anti-inflammatoires se traduisant par une réduction significative des lésions inflammatoires macroscopiques et microscopiques de l’iléon. Cet effet est associé à une réduction de la dysbiose intestinale et normalise les niveaux de PAMs dans les cellules de Paneth drastiquement réduits lors de l’iléite. Dans le modèle WAS, le LA et la fraction contenant l’activité en lysozyme réduisent l’hypersensibilité viscérale, l’état micro-inflammatoire induites par le stress et restaurent les niveaux de PAMs dans les cellules de Paneth réduits par le stress. Un traitement thermique de 2 min/72°C permet d’augmenter la durée de vie du LA tout en conservant l’activité du lysozyme et ses propriétés santé sur la muqueuse intestinale chez la souris.
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The role of cancer-induced inflammation in beta-cell apoptosisMoretti Violato, Natalia 30 November 2016 (has links)
Cancer cachexia is a complex syndrome that can affect up to 80% of cancer patients. Among the symptoms involved in cancer cachexia progression, the establishment of a systemic inflammation and the imbalance in glucose metabolism homeostasis take an important part in this profile. The aim of the present study was to further evaluate the role of cancer-induced inflammation in the impairment of pancreatic beta cell function in solid Ehrlich carcinoma-bearing mice. For that, we have focused the study in the pro-inflammatory mechanisms involved on β-cell death. We have observed that tumor-bearing animals developed an aggressive pancreatic inflammatory status 14 days after tumor cells inoculation. The increase of pro-inflammatory cytokines followed by an up-regulation of important transcription factors such as NF-κB and STAT-1 and its related genes, reveled a similar outline for β-cell death found in type 1 diabetes. Furthermore, expression of pro-apoptotic Bcl-2 family members followed by caspases activation was increased in pancreatic islets of tumor-bearing animals and the expression of anti-apoptotic members was decreased. We have also observed an increase in β-cell death and ER stress components, as well as a decrease in insulin content cells together with an increase in alpha cells content. Overall, our results provide strong evidences that pancreatic β-cells in tumor-bearing animals are widely affected by tumor presence and systemic inflammation establishment. Interestingly, it was shown a similarity with mechanisms of β-cell death found in type 1 diabetes. Although the exactly mechanisms behind the changes found in carbohydrate metabolism in cancer cachexia is still unclear, our data can help to clarify, at least in part, this profile and would serve as a basis for development of new strategies to prevent cachexia progression and to improve the quality of life of cancer patients. / Doctorat en Sciences biomédicales et pharmaceutiques (Médecine) / info:eu-repo/semantics/nonPublished
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The role of ASPP2 in intestinal cell polarity and homeostasisKoch, Sofia Morato January 2013 (has links)
No description available.
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Functional phenotyping of macrophage subsets during skeletal muscle regeneration and in degenerative myopathies / Phénotypes fonctionnels des sous populations de macrophages au cours de la régénération musculaire et lors des myopathies dégénérativesSaclier, Marielle 06 March 2014 (has links)
Le muscle squelettique a la capacité de se régénérer suite à une lésion grâce aux cellules satellites qui sont les cellules souches du muscle. Après dommage musculaire, les cellules satellites s’activent, prolifèrent, se différencient et fusionnent afin de reformer le muscle lésé. Cependant les cellules myogéniques ne sont pas les seules cellules impliquées dans la régénération musculaire. Des études précédentes réalisées au laboratoire ont montré chez la souris que les macrophages sont des cellules essentielles à la régénération musculaire. En effet, peu de temps après un dommage musculaire, les monocytes infiltrent le tissu lésé et se différencient en macrophages pro-inflammatoires Ly6Cpos (M1). Ces macrophages stimulent la prolifération des myoblastes et inhibent leur fusion. Puis les macrophages pro-inflammatoires changent de phénotype et deviennent des macrophages anti-inflammatoires Ly6Cneg (M2) qui stimulent la différenciation des myoblastes et les protègent de l’apoptose. Ainsi, en fonction de leur phénotype, les macrophages exercent des rôles trophiques séquentiels sur les myoblastes tout au long du processus de régénération musculaire. Dans la première partie de notre étude, nous montrons in vitro que les macrophages humains soutiennent les différentes étapes de la myogenèse. Les macrophages M1 sont fortement attirés par les myoblastes. De plus ils stimulent la prolifération des myoblastes et inhibent leur fusion. Les macrophages M2 attirent les myoblastes et stimulent leur différenciation permettant ainsi la formation de larges myotubes. En utilisant des anticorps bloquants spécifiques, nous avons identifié plusieurs molécules sécrétées par les macrophages régulant la myogenèse chez l’homme. Nos analyses in vivo chez l'homme confirment nos résultats obtenus in vitro. En effet, les macrophages M1 sont préférentiellement associés aux aires de régénération contenant des myoblastes non différenciés alors que les macrophages M2 sont associés aux aires de régénération contenant des myoblastes en différenciation. Dans un contexte de myopathie dégénérative, nous avons montré que les macrophages adoptent des phénotypes et des fonctions totalement différents des macrophages présents au cours de la régénération musculaire. Nous avons observé chez la souris et chez l’homme, que les macrophages exprimant des marqueurs M1 sont associés à la fibrose et qu’un traitement anti-inflammatoire réduit leur nombre dans le muscle dystrophique murin. Par isolement spécifique et cocultures ex vivo, nous avons montré qu'au cours de la régénération musculaire, les macrophages Ly6Cneg stimulent la production de collagène par les fibroblastes. A l'inverse au cours des myopathies dégénératives, ce sont les macrophages Ly6Cpos qui stimulent fortement l’établissement de la fibrose en agissant directement sur les fibroblastes. De plus, ces macrophages Ly6Cpos, qui régulent négativement les fibroblastes au cours de la régénération musculaire, stimulent la différenciation des fibroblastes et myofibroblastes dans les myopathies. De plus, ils les protègent de l'apoptose, participant ainsi à la persistance de ces cellules fibrosantes. Ainsi, nous avons confirmé chez l’homme in vitro et in vivo, le rôle de support séquentiel des macrophages au cours de la régénération musculaire. De plus, nous avons identifié différents effecteurs sécrétés par les macrophages M1 et M2 impliqués dans la régulation du processus myogénique chez l'adulte. Nous avons également montré que lors des myopathies dégénératives et au cours de la régénération musculaire, les macrophages adoptent un phénotype et des fonctions totalement différents, avec notamment un rôle profibrotique des macrophages pro-inflammatoires. / Skeletal muscle has the ability to regenerate after a chemical or physical injury thanks to satellite cells, the muscle stem cells. After damage, satellite cells proliferate, differentiate and fused to reform muscle. Myogenic cells are not the only on cells involved. Previous studies in the laboratory showed that, in mice, macrophages are crucial for skeletal muscle regeneration. Soon after an injury, macrophages infiltrate damaged muscle and differentiate into Ly6Cpos pro-inflammatory (M1) macrophages. They stimulate proliferation of myoblasts and inhibit their fusion. Then, pro-inflammatory macrophages skew towards a Ly6Cneg anti-inflammatory phenotype (M2). Anti-inflammatory macrophages stimulate differentiation of myoblasts and protect them from apoptosis. Thus, depending on their phenotype, macrophages exert sequential trophic roles on myoblasts throughout muscle regeneration. Here, we showed in vitro that human macrophages also support different steps of myogenesis. M1 macrophages are strongly attracted by mpcs. Moreover, they secrete molecules, which stimulate proliferation of mpcs and inhibit their fusion. M2 macrophages attract mpcs and stimulate differentiation of mpcs in order to form large myotubes. Using specific blocking antibodies, we identified molecules involved in the regulation of myogenesis by M1 and M2 macrophages in a human in vitro system. In vivo analysis of regenerating human muscle sections confirmed our results obtained in vitro. M1 macrophages are preferentially associated with proliferating myogenic cells while M2 macrophages are associated with differentiating myogenic cells. In degenerative myopathies, we showed that macrophages are completely different from those present during skeletal muscle regeneration. We observed in mouse and human that M1 marker-expressing macrophages are associated with fibrosis while anti-inflammatory treatment reduced this population, in association with an improvement of the dystrophic muscle. Isolated Ly6Cneg macrophages exhibit a mixed M1/M2 phenotype. In ex-vivo coculture experiments, we showed that Ly6Cpos macrophages strongly favor establishment of fibrosis by directly acting on fibroblasts while in regenerating muscle, these Ly6Cpos macrophages negatively regulate fibrosis. To resume, we confirm in human the supportive sequential roles of macrophages during skeletal muscle regeneration in vitro and in vivo. Moreover, we identified effectors secreted by M1 and M2 macrophages involved in the regulation of the myogenic process. We also highlight that during muscle regeneration and in degenerative myopathies, macrophages exhibit different phenotype associated with opposite functions, with a pro-fibrotic role for pro-inflammatory macrophages.
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Spinal stenosis and intervertebral disc disease:the role of sequence variations in collagen IX and XI, and inflammatory factors in spinal disordersNoponen-Hietala, N. (Noora) 16 May 2005 (has links)
Abstract
Genetic factors have been implicated to play a role in both degenerative lumbar spinal stenosis (LSS) and intervertebral disc disease (IDD). Sequence variations in the genes coding for collagen IX and inflammatory mediators have been indicated as risk factors for IDD.
Nine genes coding for intervertebral disc (IVD) collagens I, II, IX and XI and aggrecan (AGC1) were analyzed for sequence variations in 29 Finnish individuals with LSS. In addition, two polymorphisms in the vitamin D receptor gene and one in the matrix metalloproteinase-3 gene were studied. Study subjects were analyzed both clinically and radiologically. Results indicated an association between the COL11A2 IVS6-4 a to t polymorphism and LSS (p = 0.0016). Moreover, the t/t genotype was found more often in the patient group compared to controls (p = 0.0011). A novel splicing mutation, likely resulting in the synthesis of a truncated protein, was identified in COL9A2.
Eight hundred four Chinese individuals were screened for the presence of the Trp2 and Trp3 alleles. The Trp2 allele was found in 20% of the individuals compared to the previously reported 5% in Finnish patients with IDD characterized by sciatica. The Trp2 allele was found to predispose to IVD degeneration and end plate herniations, increasing the risk by 2.4-fold from 40 to 49 years of age. In addition, the degeneration was worse in individuals with the Trp2 allele. The risk for annular tears was 4-fold greater in study subjects from 30 to 39 years of age who were Trp2 positive. Surprisingly, the Trp3 allele was absent even though it was found in about 9% of Finnish individuals.
One hundred fifty-five Finnish individuals with IDD characterized by sciatica were analyzed for sequence variations in four genes coding for inflammatory mediators IL1A, IL1B, IL6, and TNFA. In addition, sixteen polymorphisms in inflammatory mediator genes were analyzed. The results identified an association between sciatica and the E5+15T>A polymorphism in IL6 (p = 0.007). A significant association was also seen in the IL6 haplotype analysis (-597 g>a, -572 g>c, -174 g>c and E5+15T>A). The association of the GGGA haplotype with the disease was highly significant (p = 0.0033).
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Macrophages, monocytes and interleukin-6 in chronic obstructive pulmonary diseaseRavi, Arjun Kumar January 2016 (has links)
Background: COPD is associated with an increased lung macrophage burden. Whilst lung macrophages may self-renew, recruitment of peripheral blood monocytes from the systemic circulation is considered to represent their principal means of replenishment. Through modulating expression of monocytic chemokines CCL2/CCL3 and their respective receptors (CCR2/CCR1+CCR5), IL-6 could play a key role in facilitating the recruitment of monocytes to the lungs of COPD patients. COPD is associated with enhanced pulmonary and systemic IL-6 levels; concentrations of the soluble IL-6 receptor sIL-6R may be an important determinant of IL-6 signalling in COPD. Trans-signalling through sIL-6R, IL-6 may facilitate recruitment of monocytes in COPD by influencing chemokine and chemokine receptor expression. Aims: 1) To compare levels of IL-6, sIL-6R, CCL2 and CCL3 in the plasma and sputum of COPD and controls. 2) To examine of the effects of IL-6 stimulation on monocyte chemokine receptor gene expression (CCR1, CCR2 and CCR5). 3) To compare subtypes (CD14++CD16-, CD14+CD16+, CD14-CD16++) and chemokine receptor expression (CCR1, CCR2, CCR5) of monocytes in COPD (paired stable & exacerbating) and controls. 4) To compare the migratory ability of monocytes from COPD and controls. 5) To compare numbers of marginated CX3CR1+ monocytes in the pulmonary microvasculature and proliferation status (Ki67 positivity) of alveolar macrophages in COPD and controls. Methods: 1) MSD soluble marker analysis was performed on plasma and sputum supernatant. 2) Monocytes underwent stimulation with IL-6 and sIL-6R; chemokine receptor expression was determined by quantitative PCR. 3) Flow cytometry was performed on whole blood to determine monocyte subtype and chemokine receptor expression. 4) Monocyte migration towards sputum supernatant was assessed using a transwell system incorporating fluorescence based detection of DNA from migrated cells. 5) Immunofluorescence and immunohistochemistry was performed on lung tissue (obtained from patients undergoing surgical resection of lung carcinoma) to identify marginated (CX3CR1+CD14+, CX3CR1+CD16+) monocytes and proliferating alveolar macrophages (Ki67) respectively. Results and Conclusion: Levels of sIL-6R were increased in the lungs and systemic circulation of COPD patients implying potential for enhanced IL-6 trans-signalling: monocytes cultured in the presence of IL-6+sIL-6R upregulated expression of the CCR5 gene. A greater proportion of circulating COPD CD14++CD16- and CD14+CD16+ monocytes were demonstrated to express CCR5 compared to controls indicating that CCR5 ligands may have an important influence over monocyte migration in COPD. Levels of CCR5 ligand CCL3 were significantly elevated in COPD sputum supernatant; IL-6 levels were positively associated with CCL3 indicating that IL-6 trans-signalling may mediate lung chemokine expression. Nevertheless, COPD monocytes demonstrated impaired migration towards sputum supernatant and reduced margination to pulmonary microvessels. Despite this, the number of alveolar macrophages in COPD was increased; however this was not likely to be related to self-replication owing to low alveolar macrophage Ki67 expression.
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