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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The role of Annexin-A1 in the pathophysiology of diabetes

Purvis, Gareth S. D. January 2018 (has links)
Diabetes is a complex disease characterised by hyperglycaemia, which often leads to microvascular complications including diabetic nephropathy and cardiomyopathy. In this thesis, I have investigated the role of Annexin-A1 (ANXA1), an endogenous anti-inflammatory peptide, in two experimental murine models of diabetes caused by streptozotocin (STZ) or high-fat high-sugar diet (HFD), which mimic type-1 (T1DM) and type-2 diabetes (T2DM) respectively. I have also investigated the levels of ANXA1 in patients with either T1DM or T2DM. Patients with T1DM have increased plasma ANXA1 levels. In a murine models of type 1 diabetes loss of endogenous ANXA1 aggravates both cardiac and renal dysfunction in mice. Specifically, I have shown that key mediators of the MAPK pathway (p38, JNK and ERK1/2) are constitutively activated in ANXA1-/- mice, and activation of these pathways is exacerbated in diabetic ANXA1-/- mice. Administration of human recombinant (hr) ANXA1 did not alter the diabetic phenotype in diabetic WT mice, but attenuated the cardiac and renal dysfunction caused by STZ. Interestingly, late administration of ANXA1 (after significant cardiac and renal dysfunction had already developed) halted the progression of both cardiac and renal dysfunction. Patients with T2DM have increased plasma ANXA1 levels. HFD-fed ANXA1-/- mice have a more severe diabetic phenotype compared to HFD-fed WT mice. Therapeutic administration of hrANXA1 prevented the development of a diabetic phenotype. Specifically, I have shown that the insulin signalling pathway is further perturbed in diabetic mice resulting in severe insulin resistance, and that these signalling abnormalities were prevented by therapeutic administration of hrANXA1. In addition, loss of endogenous ANXA1 aggravates both cardiac and renal dysfunction in mice with experimental T2DM. The GTPase RhoA is constituently activated in ANXA1-/- mice leading downstream activation of MYPT1. Feeding a HFD also activated the small GTPase RhoA, leading to increased MYPT1 activity, which could be attenuated with treatment with hrANXA1. Mice subjected to HFD for 12 weeks had a more 'leaky' blood brain barrier (BBB), which is further exacerbated in ANXA1-/- mice fed a HFD. Compared to mice fed a chow diet, mice fed a HFD had an augmented CD4+ T-cell profile; with a clear decline in CD4+FoxP3+ (anti-inflammatory) and increase in CD4+RORgt+ (pro-inflammatory) cells. Administration of hrANXA1 to mice fed on HFD restored BBB integrity and CD4+ T-cells profile similar to mice fed on normal chow diet. Mice fed a HFD also had more activated CD4+ T-cells, which adhered more readily and transmigrated through a brain endothelial mono-layer ex vivo. In contrast, administration of hrANXA1 to mice fed on HFD reduced re-activity of CD4+ T-cells, reducing the number of adherent CD4+ T-cells to the brain endothelial mono-layer.
2

A novel proinflammatory role for annexin A1 in neutrophil transendothelial migration.

Williams, Samantha Louise January 2009 (has links)
Neutrophil extravasation into tissues is an essential process required for the inflammatory response. Upon receiving an inflammatory cue, neutrophils begin accumulating on the luminal surface of the endothelium. Neutrophil recruitment is initiated by selectin-mediated tethering and rolling of neutrophils along the endothelial monolayer, followed by integrin-mediated firm adhesion. Adherent neutrophils then traverse the endothelium in a process known as transendothelial migration. The events mediating the rolling and adhesion steps are well characterised, but research into the molecular mechanisms regulating transendothelial migration is an area of intense focus. A previous study conducted in our laboratory found that the activation of endothelial extracellular signal-regulated kinase (ERK) 1/2 was required for neutrophil transmigration. Furthermore, it was found that endothelial ERK was activated in response to a soluble protein produced by fMLP- or IL-8-stimulated neutrophils. In the present study, the soluble ERK-activating neutrophil protein was identified as annexin A1, which was selected as a possible candidate following mass spectrometry analysis of proteins secreted from activated neutrophils. Annexin A1 antibodies (Abs) were found to block endothelial ERK activation induced by conditioned medium harvested from stimulated neutrophils. Annexin A1 Abs were additionally able to inhibit neutrophil transmigration across human umbilical vein endothelial cell (HUVEC) monolayers in an in vitro transmigration assay. Following the purification of recombinant annexin A1, it was demonstrated that it could activate endothelial ERK in a similar manner to neutrophil conditioned medium. Upon further investigation, ERK activation was found to be induced by a truncated form of annexin A1 present in the protein preparation rather than the full length protein. Calpain I, a calcium dependent protease that is activated upon neutrophil stimulation and is known to cleave annexin A1 within the N-terminal domain, was shown to process full length inactive recombinant annexin A1 into an unidentified product that could activate endothelial ERK. A calpain I inhibitor was also found to prevent stimulated neutrophils from secreting an ERK-activating protein, thus further suggesting a role for calpain I in this process. As full length annexin A1 has been reported to signal through the formyl peptide receptor (FPR) family, a pan-FPR antagonist was incubated with endothelial cells and was found to inhibit ERK activation induced by neutrophil conditioned medium, indicating that pro-inflammatory annexin A1 is also a FPR ligand. Endothelial projections termed “transmigratory cups” form around neutrophils during extravasation, of which ICAM-1 is a major component. Using an assay that examined transmigratory cups during neutrophil transmigration, it was found that annexin A1 Abs could inhibit neutrophil adhesion and transmigration through HUVEC monolayers by interfering with transmigratory cup formation around neutrophils, as shown by monitoring ICAM-1 during the process. Quantification of transmigrating neutrophils highlighted that the majority of neutrophils were emigrating via a transcellular pathway, which is in opposition to many in vitro studies where paracellular transmigration predominates. The results generated from this study identified a novel pro-inflammatory role for annexin A1 in neutrophil transendothelial migration. Preliminary experiments suggested that the pro-inflammatory annexin A1 responsible for endothelial ERK activation was a truncated form. Calpain I appears to be a likely candidate responsible for the generation of this uncharacterised, truncated annexin A1 product, however further experiments are required to confirm this hypothesis. Pro-inflammatory annexin A1 represents a new target for the treatment of inflammatory disorders. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1374554 / Thesis (Ph.D.) -- University of Adelaide, School of Molecular and Biomedical Science, 2009
3

Controle da Anexina 1 sobre a expressão do receptor nuclear proliferador de peroxissomos em diferentes tipos celulares / Control of Annexin A1 in the peroxissome proliferator receptor expression in different cell types

Takahama, Carina Harumi 21 July 2016 (has links)
A proteína Anexina A1 (ANXA1), sintetizada e liberada por fagócitos pela ação de glicocorticóides, é uma proteína anti-inflamatória, pois inibe o influxo de neutrófilos para o foco da inflamação, e induz os mecanismos de eferocitose em neutrófilos e macrófagos. Nosso grupo mostrou que a ANXA1 regula a expressão do receptor ativado por proliferadores de peroxissomos (PPAR) em macrófagos. Em continuidade, o presente trabalho investigou o mecanismo da ANXA1 sobre a expressão de PPARγ em macrófagos, e se este controle ocorre em demais leucócitos e tecido adiposo. Para tanto, macrófagos, neutrófilos peritoneais, linfócitos do baço, tecido adiposo epididimal foram obtidos de camundongos machos Balb/c selvagens (wild type, WT) ou geneticamente deficientes para ANXA1 (ANXA1-/-). Os resultados obtidos mostraram que a ANXA1 controla a expressão proteica e gênica de PPARγ em macrófagos, já que os níveis proteico (Western Blot, WB) e de RNAm (Real-time PCR) para PPARγ constitutivo, bem como induzidos pelos tratamentos in vitro com bezafibrato ou pioglitazona estavam reduzidos em macrófagos de animais ANXA1-/- em comparação com os níveis de macrófagos de animais WT, e o efeito parece ser dependente de CREB (WB), já que os níveis constitutivos deste fator de transcrição estavam maiores em macrófagos de animais ANXA1-/-. O tratamento in vitro com cicloheximida (CHX), um inibidor da síntese proteica, reduziu a expressão de PPARγ estimulada por bezafibrato ou LYSO-7 em macrófagos de animais WT, reforçando o papel da ANXA1 na expressão gênica de PPARγ. O FPR2 parece não estar envolvido no efeito, uma vez que o pré-tratamento de macrófagos com o antagonista de FPR2 (WRW4) não modificou a expressão de PPARγ em macrófagos de animais WT. O efeito modulador da ANXA1 ocorre em neutrófilos, mas não em tecido adiposo e linfócitos de animais ANXA1-/-. Ademais, a deficiência de ANXA1 não alterou a apoptose espontânea de neutrófilos. Em conjunto, os resultados obtidos mostram uma possível via adicional da ANXA1 sobre a resolução da inflamação, controlando a expressão de PPARγ em fagócitos. / Annexin A1 (ANXA1), is a protein synthetized and released by phagocytes due to the action of glucocorticoids, and an anti-inflammatory protein that inhibits neutrophil influx to site of inflammation and induces the mechanisms of efferocytosis in neutrophils and macrophages. Our group has already demonstrated that ANXA1 regulates the expression of peroxisome proliferator-activated receptor (PPAR) in macrophages. The present work aimed to investigate the role of ANXA1-dependent mechanisms on the expression of PPARγ in macrophages, and if said role also extends to other leukocytes and adipose tissue. For such, macrophages, peritoneal neutrophils, spleen lymphocytes, epididymal adipose tissue were obtained from male Balb/c wild type mice or from mice lacking ANXA1 genetically (ANXA-/-). Obtained results have demonstrated that ANXA1 regulates both proteic and genic expression of PPARγ in macrophages, as protein (Western Blotting, WB) and mRNA (Real-Time PCR) levels of constitutive PPARγ were reduced in macrophages from ANXA1-/- mice in comparison with the observed levels of macrophages from WT mice; the same is true for increased protein and mRNA levels as induced by in vitro treatments with bezafibrate or pioglitazone. This effect appears to be CREB-dependent (WB), as the constitutive levels of this transcription factor were found to be increased in macrophages from ANXA1-/- mice. In vitro treatment with cycloheximide (CHX), an inhibitor of proteic synthesis, reduced the bezafibrate or LYSO-7 (PPAR pan agonist, 10 µM / 2h) induced expression of PPARγ in WT mice, which further suggests a role for ANXA1 in PPARγ genic expression. FPR2 does not seem to be involved with these effects of ANXA1, as pre-treatment of macrophages from WT mice with an FPR2-antagonist (WRW4) did not alter expression of PPARγ. The modulating effect of ANXA1 can be verified in neutrophils of ANXA-/- mice, but not in adipocytes and lymphocytes from the same animals. Moreover, deficiency of ANXA1 did not affect spontaneous apoptosis of neutrophils. Altogether, the obtained results show the existence of a probable additional pathway with which ANXA1 promotes inflammation resolution, also controlling the expression of PPARγ in phagocytes.
4

Annexin A1 as an endogenous regulator of mast cell degranulation

Sinniah, Ajantha January 2015 (has links)
Annexin A1 (Anx-A1) is a 37kDa protein that is secreted by some cells in response to glucocorticoids (GCs) and which mediates several of their acute anti-inflammatory effects. In addition to GCs, ‘mast cell stabilising’ cromones such as nedocromil also mobilise Anx-A1 by promoting its phosphorylation by protein kinase C (PKC) and hence its secretion, which explains their acute efficacy as anti-allergic agents. This thesis addresses a fundamental aspect of Anx-A1 in the actions of anti-allergic drugs. In this study, anti-allergic drugs such as H1 antagonists, mast cell stabilisers and ‘dual action’ drugs were first tested for their ability to enhance Anx-A1 phosphorylation in a model system using U937 cells. Biochemical and immuno-fluorescent techniques were used to study the mechanisms by which these drugs suppress mediator release from cord blood derived mast cells (CDMCs) and murine bone-marrow derived mast cells (BMDMCs) from wild type and Anx-A1 null-mice. This thesis suggest that PKC activation is crucial for Anx-A1 export in mast cells and nedocromil in the presence of dexamethasone, prolongs the duration of PKC activation and subsequently phosphorylation, externalisation and release of Anx-A1 from CDMCs. The ability of nedocromil to inhibit β-hexosaminidase, tryptase, histamine and PGD2 release are dependent on Anx-A1 in CDMCs. Interestingly, ketotifen, a ‘dual action’ drug possesses a similar pharmacological profile to nedocromil, but not promethazine, which does not act through the Anx-A1 release. Strong evidence supports the notion that the mechanisms of action of nedocromil are modulated by Anx-A1, thus the possibility that FPR2 might be involved in the acute actions of nedocromil was tested. Nedocromil inhibits the release of PGD2 through the activation of FPR2 but not the inhibition of histamine release. A possible explanation for this finding could be that Anx-A1 might be interacting with other FPR family members to exert the histamine inhibitory effects. Although only a small subset of the downstream intracellular signaling pathway of MAPK was tested, the results indicate that Anx-A1 differentially regulates the activation of p38 and JNK in CDMCs treated with nedocromil. These findings indicate a novel model system in which Anx-A1 mediates the pharmacological actions of anti-allergic drugs and thus has an important role in preventing the mast cell degranulation.
5

Controle da Anexina 1 sobre a expressão do receptor nuclear proliferador de peroxissomos em diferentes tipos celulares / Control of Annexin A1 in the peroxissome proliferator receptor expression in different cell types

Carina Harumi Takahama 21 July 2016 (has links)
A proteína Anexina A1 (ANXA1), sintetizada e liberada por fagócitos pela ação de glicocorticóides, é uma proteína anti-inflamatória, pois inibe o influxo de neutrófilos para o foco da inflamação, e induz os mecanismos de eferocitose em neutrófilos e macrófagos. Nosso grupo mostrou que a ANXA1 regula a expressão do receptor ativado por proliferadores de peroxissomos (PPAR) em macrófagos. Em continuidade, o presente trabalho investigou o mecanismo da ANXA1 sobre a expressão de PPARγ em macrófagos, e se este controle ocorre em demais leucócitos e tecido adiposo. Para tanto, macrófagos, neutrófilos peritoneais, linfócitos do baço, tecido adiposo epididimal foram obtidos de camundongos machos Balb/c selvagens (wild type, WT) ou geneticamente deficientes para ANXA1 (ANXA1-/-). Os resultados obtidos mostraram que a ANXA1 controla a expressão proteica e gênica de PPARγ em macrófagos, já que os níveis proteico (Western Blot, WB) e de RNAm (Real-time PCR) para PPARγ constitutivo, bem como induzidos pelos tratamentos in vitro com bezafibrato ou pioglitazona estavam reduzidos em macrófagos de animais ANXA1-/- em comparação com os níveis de macrófagos de animais WT, e o efeito parece ser dependente de CREB (WB), já que os níveis constitutivos deste fator de transcrição estavam maiores em macrófagos de animais ANXA1-/-. O tratamento in vitro com cicloheximida (CHX), um inibidor da síntese proteica, reduziu a expressão de PPARγ estimulada por bezafibrato ou LYSO-7 em macrófagos de animais WT, reforçando o papel da ANXA1 na expressão gênica de PPARγ. O FPR2 parece não estar envolvido no efeito, uma vez que o pré-tratamento de macrófagos com o antagonista de FPR2 (WRW4) não modificou a expressão de PPARγ em macrófagos de animais WT. O efeito modulador da ANXA1 ocorre em neutrófilos, mas não em tecido adiposo e linfócitos de animais ANXA1-/-. Ademais, a deficiência de ANXA1 não alterou a apoptose espontânea de neutrófilos. Em conjunto, os resultados obtidos mostram uma possível via adicional da ANXA1 sobre a resolução da inflamação, controlando a expressão de PPARγ em fagócitos. / Annexin A1 (ANXA1), is a protein synthetized and released by phagocytes due to the action of glucocorticoids, and an anti-inflammatory protein that inhibits neutrophil influx to site of inflammation and induces the mechanisms of efferocytosis in neutrophils and macrophages. Our group has already demonstrated that ANXA1 regulates the expression of peroxisome proliferator-activated receptor (PPAR) in macrophages. The present work aimed to investigate the role of ANXA1-dependent mechanisms on the expression of PPARγ in macrophages, and if said role also extends to other leukocytes and adipose tissue. For such, macrophages, peritoneal neutrophils, spleen lymphocytes, epididymal adipose tissue were obtained from male Balb/c wild type mice or from mice lacking ANXA1 genetically (ANXA-/-). Obtained results have demonstrated that ANXA1 regulates both proteic and genic expression of PPARγ in macrophages, as protein (Western Blotting, WB) and mRNA (Real-Time PCR) levels of constitutive PPARγ were reduced in macrophages from ANXA1-/- mice in comparison with the observed levels of macrophages from WT mice; the same is true for increased protein and mRNA levels as induced by in vitro treatments with bezafibrate or pioglitazone. This effect appears to be CREB-dependent (WB), as the constitutive levels of this transcription factor were found to be increased in macrophages from ANXA1-/- mice. In vitro treatment with cycloheximide (CHX), an inhibitor of proteic synthesis, reduced the bezafibrate or LYSO-7 (PPAR pan agonist, 10 µM / 2h) induced expression of PPARγ in WT mice, which further suggests a role for ANXA1 in PPARγ genic expression. FPR2 does not seem to be involved with these effects of ANXA1, as pre-treatment of macrophages from WT mice with an FPR2-antagonist (WRW4) did not alter expression of PPARγ. The modulating effect of ANXA1 can be verified in neutrophils of ANXA-/- mice, but not in adipocytes and lymphocytes from the same animals. Moreover, deficiency of ANXA1 did not affect spontaneous apoptosis of neutrophils. Altogether, the obtained results show the existence of a probable additional pathway with which ANXA1 promotes inflammation resolution, also controlling the expression of PPARγ in phagocytes.
6

Hydrodynamic stress stimulates growth of cell clusters via the ANXA1/PI3K/AKT axis in colorectal cancer / 流体力学的ストレスはANXA1を誘導し、PI3K/AKTシグナル活性化を介して大腸癌細胞塊の成長を促進する

Hagihara, Takeshi 23 March 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22374号 / 医博第4615号 / 新制||医||1043(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 武藤 学, 教授 松田 道行, 教授 小西 靖彦 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
7

Expressão da anexina-A1 em leucócitos de pacientes com hanseníase

Ribeiro, Afonso Bezerra 22 September 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-09-18T13:31:10Z No. of bitstreams: 1 DISS_2014_Afonso Bezerra Ribeiro.pdf: 2755836 bytes, checksum: 9328d5ba556fe7eb6eb229cb1cd9ecdc (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-09-19T15:50:05Z (GMT) No. of bitstreams: 1 DISS_2014_Afonso Bezerra Ribeiro.pdf: 2755836 bytes, checksum: 9328d5ba556fe7eb6eb229cb1cd9ecdc (MD5) / Made available in DSpace on 2017-09-19T15:50:05Z (GMT). No. of bitstreams: 1 DISS_2014_Afonso Bezerra Ribeiro.pdf: 2755836 bytes, checksum: 9328d5ba556fe7eb6eb229cb1cd9ecdc (MD5) Previous issue date: 2014-09-22 / A hanseníase é uma doença infecto contagiosa, endêmica, de evolução crônica, granulomatosa causada pelo M. leprae, que representa um grave problema de saúde pública no Brasil e em vários países do mundo. O objetivo deste estudo foi analisar as populações de neutrófilos, monócitos, células T CD4+, T CD8+ e T regulatórias no sangue periférico de pacientes com hanseníase nas formas clínicas multibacilar e paucibacilar bem como a expressão da proteína anti-inflamatória ANXA1 e os níveis de IL-10. A quantificação de leucócitos no sangue periférico dos pacientes com hanseníase e seus controles (indivíduos sadios sem histórico clínico de infecção – controle negativo; e paciente com tuberculose – controle positivo) foi realizada através da contagem em câmara hemocitométrica de Neubauer e diferencial em esfregaço sanguíneo. A determinação do fenótipo das células T CD4+, TCD8+ e Treg foi realizada através de imunofluorescência. A expressão da ANXA1 e os níveis de IL-10 nos leucócitos e plasma forma através das técnicas de imunofluorescência e ELISA. Os resultados foram analisados através da análise de variância (One-way ANOVA) com pós teste de Bonferroni. As associações entre dados não paramétricos foram analisadas por regressão linear e pelo coeficiente de correlação do teste de Spearman. Os resultados demonstraram queos leucócitos totais nos pacientes MB (22,93 x 106 ± 0,37 cel/mL) e PB (26,58 x 106 ± 1,12 cel/mL) apresentaram um aumento significativo do número de células quando comparado ao grupo CS (6,43 x 106 ± 0,74 cel/mL). Já grupo PB apresentou um aumento significativo também em relação ao grupo CP (21,45 x 106 ± 0,38 cel/mL). A população de monócitos nos pacientes MB estava aumentada (1,45 x 106 ± 0,28 cel/mL) quando comparados ao grupo CS (0,59 x 106 ± 0,70 cel/mL) e CP (0,70 x 106± 0,17 cel/mL). O grupo dos PB (0,23 x 106 ± 0,04 cel/mL) quando comparado ao grupo CS e CP não apresentou um aumento significativo entre os grupos. Já os neutrófilos dos pacientes MB (14,04 x 106 ± 0,53 cel/mL) quanto dos PB (14,28 x 106 ± 0,22 cel/mL) apresentaram aumento significativo em relação aos CS (3,42 x 106 ± 0,36 cel/mL) e CP (1,21 x 106 ± 0,06 cel/mL). Nas células T CD4+, foi observado um aumento nas formas clínicas MB (1,99 x 106 ± 0,29 cel/mL) e PB (1,89 x 106 ± 0,18 cel/mL) comparado aos controles sadio e positivo. Em relação as células T CD8+ , o número desse leucócito foi mais expressivo na forma MB (1,14 x 106 ± 0,10 cel/mL), do que o grupo CS (0,62 x 106 ± 0,05 cel/mL), enquanto que o grupo PB (0,28 x 106 ± 0,02 cel/mL) apresentou redução em relação ao grupo CS. Na população de células Treg, a forma clínica MB (1,85 x 106 ± 0,27) apresentou maior número quando comparado ao grupo CS (0,56 x 106 ± 0,07 cel/mL) e CP (0,30 x106 ± 0,02 cel/mL). O grupo PB (0,29 x 106± 0,03 cel/mL) não apresentou aumentou significativo quando comparado ao grupo CS e CP. A ANXA1 apresentou redução em leucócitos circulantes nos pacientes PB e MB, porém apresentou altos níveis liberada no plasma, sendo que os pacientes multibacilares apresentaram níveis superiores aos paucibacilares. Por se tratar de uma molécula reguladora da inflamação, sua ação parácrina poderia estar potencializando a ação anti-migratória e inibindo a ação pró-inflamatória nos leucócitos circulantes na infecção induzida por M. leprae, principalmente nos pacientes multibacilares. Nenhuma correlação foi observada entre a expressão da anexina-A1 e os níveis de IL-10 nos pacientes com hanseníase, indicando que essa proteína não está envolvida no mecanismo de indução de produção dessa citocina nos leucócitos circulantes. / Leprosy is endemic, infectious disease of chronic evolution, granulomatous caused by M. leprae, which represents a serious public health problem in Brazil and in countries around the world. The aim of this study was to analyze the populations of neutrophils, monocytes, TCD4+ cells, TCD8+ and T regulatory peripheral blood of patients with leprosy in multibacillary clinical and paucibacillary forms as well as the expression of anti-inflammatory ANXA1 protein and the levels of IL -10. Quantification of leukocytes in peripheral blood of leprosy patients and controls (healthy individuals without clinical history of infection - negative control, and patient with tuberculosis - positive control) was performed by hemocytometer Neubauer chamber counting and differential blood smear. The determination of the phenotype of TCD4+, TCD8+ and Treg cells was performed by immunofluorescence. The expression of ANXA1 and IL-10 levels in plasma and leukocytes by way of immunofluorescence and ELISA. The results were analyzed by analysis of variance (One-way ANOVA) with Bonferroni post test. The associations between non-parametric data were analyzed by linear regression and the correlation coefficient of Spearman. The results showed that the total leukocytes in patients MB (22.93 ± 0.37 x 106 cells / ml) and BP (26.58 ± 1.12 x 106 cells / ml) showed a significant increase in cell number when compared the CS group (6.43 ± 0.74 x 106 cells / mL). The CP group showed a significant increase also in relation to the CP group (21.45 ± 0.38 x 106 cells / ml). The population of monocytes in MB patients was increased (1.45 ± 0.28 x 106 cells / mL) compared to the CS group (0.59 ± 0.70 x 106 cells / mL) and CP (0.70 x 106 ± 0.17 cells / mL). The group of PB (0.23 x 0.04 ± 106 cells / mL) compared to CS and CP group did not show a significant increase between the groups. Neutrophils of MB patients (14.04 ± 0.53 x 106 cells / mL) and the PB (14.28 ± 0.22 x 106 cells / mL) showed a significant increase from the CS (3.42 x 106 ± 0.36 cell / ml) and CP (1.21 ± 0.06 x 106 cells / ml). TCD4+ cells, an increase was observed in clinical forms MB (1.99 ± 0.29 x 106 cells / ml) and BP (1.89 ± 0.18 x 106 cells / ml) compared to healthy, positive controls. Regarding the TCD8+ cells, the number of leukocytes was more significant in MB (1.14 x 0.10 ± 106 cells / mL) than the CS group (0.62 ± 0.05 x 106 cells / mL ), while the PB group (0.28 ± 0.02 x 106 cells / mL) decreased compared to the CS group. In the population of Treg cells, the clinical form MB (1.85 x 106 ± 0.27) had a higher number compared to the CS group (0.56 ± 0.07 x 106 cells / mL) and CP (0.30 x106 ± 0.02 cells / mL). The CP group (0.29 ± 0.03 x 106 cells / mL) had not increased significantly when compared to the CS group and CP. The ANXA1 decreased in circulating leukocytes in patients PB and MB, but showed high levels released into the plasma, and the multibacillary patients had levels above the paucibacillary. Being a regulatory molecule of inflammation, its paracrine action might be enhancing the anti-migratory action and inhibiting pro-inflammatory action in circulating leukocytes in infection induced by M. leprae, particularly in MB patients. No correlation was observed between the expression of annexin-A1 and IL-10 levels in patients with leprosy, indicating that this protein is not involved in the production of this cytokine induction mechanism in circulating leukocytes.
8

Análise da expressão da Anexina A1 na pele de pacientes com leishmaniose cutânea e correlação com o aspecto histopatológico

Silva, Helen Aguiar Lemes da 27 March 2015 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-04-18T21:33:42Z No. of bitstreams: 1 DISS_2015_Helen Aguiar Lemes da Silva.pdf: 1095638 bytes, checksum: 6455f6c98e8a5cf2bacf4cd9e2f12fae (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-27T17:33:09Z (GMT) No. of bitstreams: 1 DISS_2015_Helen Aguiar Lemes da Silva.pdf: 1095638 bytes, checksum: 6455f6c98e8a5cf2bacf4cd9e2f12fae (MD5) / Made available in DSpace on 2018-04-27T17:33:09Z (GMT). No. of bitstreams: 1 DISS_2015_Helen Aguiar Lemes da Silva.pdf: 1095638 bytes, checksum: 6455f6c98e8a5cf2bacf4cd9e2f12fae (MD5) Previous issue date: 2015-03-27 / FAPEMAT / CNPq / A leishmaniose tegumentar americana é causada por protozoários do gênero Leishmania e a transmissão ocorre através da picada de flebotomíneos. É uma doença infecciosa, que acomete pele e mucosa. A resposta imune celular tem sido apontada como um importante fator na progressão das lesões da leishmaniose tegumentar. A proteína anti-inflamatória anexina-A1 é reconhecida como um importante mediador no processo inflamatório. O objetivo deste trabalho foi quantificar a expressão da anexina-A1, nos macrófagos e nas células T CD4+ e T CD8+ de fragmento da pele de paciente com leishmaniose cutânea, e correlacionar com o aspecto histopatológico. Biópsias de pele de pacientes (n=55) com leishmaniose cutânea foram processadas e analisadas. Para caracterizar a espécie de Leishmania foi utilizada PCR–ITS1/RFLP, identificando que todas as amostras biológicas apresentavam o parasita Leishmania brasiliensis. Na análise histopatológica, observou-se intensa migração leucocitária, evidenciando infiltrado histiolinfoplasmocitário. Em seguida foi realizada a determinação da expressão de anexina-A1 nos macrófagos e nas células T CD4+ e T CD8+ dos pacientes pela técnica de imunofluorescência. Na quantificação da expressão da anexina-A1, observou-se um aumento dessa proteína nos macrófagos da pele de pacientes com leishmaniose cutânea, quando comparados com essas células em individuos saudáveis (controle: 64,6 ± 3,0 UA; LT: 107,0 ± 2,7 UA; p<0,0001). Esses dados podem indicar a atuação dessa proteina durante o processo de fagocitose. Além disso, os macrófagos presentes nas lesões do tipo reação exudativa necrótica da pele de pacientes com leishmaniose cutânea apresentavam maior expressão dessa proteína (123,5 ± 6,9 UA) quando comparados com as células presentes nas lesões do tipo reação exudativa granulomatosa e reação exudativa celular (100,0 ± 4,1, p<0,01; e 104,6 ± 3,0, p<0,05). Esses dados podem indicar que, nas lesões do tipo reação exudativa necrótica, os macrófagos expressam mais anexina-A1 devido a ativação celular para fagocitose dos parasitas e de fragmentos celulares provenientes das regiões necróticas. Com relação as células T CD4+ e T CD8+, nossas análises demonstraram que essas células apresentavam maiores níveis de anexina-A1 nas lesões do tipo reação exudativa celular (TCD4+: 123,9 ± 11,6 UA) (TCD8+: 121,3 ± 9,0 UA), quando comparadas com as células presentes nas lesões do tipo reação exudativa granulomatosa e reação exudativa necrótica (TCD4+: 87,7 ± 5,2, p<0,05; e 53,7 ± 15,7, p<0,01) (TCD8+: 76,0 ± 11,4, p<0,05; e 77,0 ± 10,4, p<0,05). Esses dados demonstram que essa proteína está expressa durante a resposta celular frente aos antígenos da Leishmania. Além disso, a expressão aumentada da anexina-A1 nas células T presentes nas lesões do tipo reação exudativa celular pode ser explicada pelo aspecto mais disseminado do infiltrado histiolinfoplasmocitário, com maior presença de edema e ausência de contenção da infecção como ocorre nas lesões do tipo reação exudativa granulomatosa. Em conclusão, os dados apresentados nesse trabalho, em associação com os dados da literatura, demonstram a relevância da dinâmica da anexina-A1 na regulação do sistema imunológico durante a leishmaniose cutânea. Esses dados trazem, pela primeira vez, uma contribuição para o entendimento do papel da anexina-A1 na ativação dos macrófagos e células T na leishmaniose cutânea. Estudos futuros permitirão o entendimento preciso do mecanismo de ação da anexina-A1 no processo infeccioso da leishmaniose cutânea. / American tegumentary leishmaniasis is caused by protozoa of the genus Leishmania, and the transmission occurs through the sandflies bite. It is an infectious disease that affects the skin and mucosa. The cellular immune response has been identified as an important factor in the progression of tegumentary leishmaniasis lesions. The anti-inflammatory protein annexin A1 is recognized as an important mediator in the inflammatory process. The aim of this study is quantify the annexin-A1 expression in macrophages and CD4+ and CD8+ T cells from skin fragment of patients with cutaneous leishmaniasis, and correlates with histopathological aspects. Skin biopsies of patients (n= 55) with cutaneous leishmaniasis were processed and analyzed. To characterize the species of Leishmania, it was used ITS1-PCR/RFLP, which identified that all biological samples had parasite Leishmania brasiliensis. In the histological analysis, there was an intense leukocyte migration, showing lymphohistiocytic and plasmocytic infiltrate. Then, it was conducted the determination of annexin-A1 expression in macrophages and CD4+ and CD8+ T cells by immunofluorescence technique. In annexin-A1 expression quantification, there was an increase of this protein in macrophages from patients skin with cutaneous leishmaniasis, when compared to these cells from healthy individuals (control: 64.6 ± 3.0 AU, LT: 107.0 ± 2.7 AU; p <0.0001). These data might indicate the role of this protein in the phagocytic process. In addition, macrophages present in the necrotic exudative reaction skin lesions of patients with cutaneous leishmaniasis showed higher expression of the protein (123.5 ± 6.9 AU) when compared with cells present in the granulomatous exudative reaction and cellular exudative reaction lesions (100.0 ± 4.1, p <0.01, and 104.6 ± 3.0, p <0.05). These data may indicate that in necrotic exudative reaction lesions, macrophages express more annexin-A1 due to cell activation induce by phagocytosis of parasites and cellular debris from necrotic regions. Regarding CD4+ and CD8+ T cells, our analysis showed that these cells had higher levels of annexin-A1 in cellular exudative reaction lesions (CD4+: 123.9 ± 11.6 AU) (CD8+: 121.3 ± 9.0 AU) when compared with cells present in necrotic exudative reaction and granulomatous exudative reaction lesions (CD4+: 87.7 ± 5.2, p <0.05; and 53.7 ± 15.7, p <0.01) (CD8+ T: 76.0 ± 11.4, p <0.05; and 77.0 ± 10.4, p <0.05). These data demonstrate that this protein is active during the cellular response to Leishmania antigens. Furthermore the increased annexin-A1 expression in T cells from cellular exudative reaction lesion could be explained by the widespread aspect of lymphohistiocytic and plasmocytic infiltrate, with higher presence of edema and absence infection containment, as occurs in the granulomatous exudative reaction lesions. In conclusion, the data presented here, together with the literature, show the relevance of the annexin-A1 dynamics in the immune system regulation during cutaneous leishmaniasis. These data shows for the first time, a contribution to understanding the role of annexin-A1 in the activation of macrophages and T cells in the cutaneous leishmaniasis. Future studies will allow the accurate understanding of the annexin-A1 mechanism of action in the infection process of cutaneous leishmaniasis.
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Regulation of Lysosomal Degradation by CA2+And CA2+-Binding Proteins

Ghislat Cherfaoui, Ghita 14 June 2013 (has links)
La macroautofagia y la endocitosis son dos procesos catabólicos conservados evolutivamente en los que, mediante un tráfico vesicular, se degrada el material secuestrado, cuyo origen es intra- y extracelular, respectivamente. Ambos procesos comienzan de manera diferente: mediante la formación de un nuevo orgánulo, el autofagosoma, que secuestra material citoplásmico (macroautofagia), o mediante la internalización de material extracelular y de algunos componentes de la membrana plasmática a través de vesículas endocíticas (endocitosis). Sin embargo, los dos terminan en el mismo compartimiento: el lisosoma. En un análisis proteómico de membranas lisosomales, purificadas a partir de fibroblastos de ratón, identificamos tres proteínas, que se unen a fosfolípidos de una manera dependiente de calcio, y cuyos niveles en la membrana lisosomal aumentaban en ausencia de aminoácidos, una condición que activa la macroautofagia. Basándonos en esos resultados iniciales, y teniendo en cuenta que el calcio es un segundo mensajero muy importante, decidimos: en primer lugar, abordar el papel del calcio en la activación de la autofagia producida por el ayuno de aminoácidos, y, en segundo lugar, investigar el papel de esas tres proteínas en el mecanismo autofágico. Como resultado de estos estudios, describimos en primer lugar una nueva vía de señalización dependiente de calcio que activa la formación de autofagosomas por los aminoácidos. Concretamente, hemos encontrado que el ayuno de aminoácidos esenciales produce un aumento en el calcio citosólico, procedente tanto del medio extracelular como de almacenes intracelulares. Como consecuencia de esto, la calmodulina quinasa quinasa- ß activa a AMPK y a mTORC1. En la última etapa de esta vía, ULK1, una quinasa responsable de la iniciación de la autofagia, se activa para contribuir a la formación de los autofagosomas. Las tres proteínas identificadas en el estudio proteómico y cuyos niveles en las membranas lisosomales aumentan en ausencia de aminoácidos son la anexina A1, la anexina A5 y la copina 1. Empleando métodos bioquímicos y de inmunofluorescencia observamos que el ayuno de aminoácidos causa la translocación de la anexina A5 desde el complejo de Golgi hasta las membranas lisosomales, donde también se acumulan la anexina A1 y la copina 1. Asimismo, demostramos por sobre-expresión y silenciamiento de esas tres proteínas, que las tres inducen la fusión de autofagosomas con lisosomas y que la copina 1, y en menor medida la anexina A1, aumentan el efecto individual de la anexina A5. Finalmente, la anexina A5 inhibe la endocitosis mientras que copina 1 la induce. En resumen, nuestros resultados ponen de manifiesto que la activación de la formación de autofagosomas por el ayuno de aminoácidos es debida, al menos en parte, a una vía de señalización dependiente de Ca2+ y que esta condición también conlleva la aceleración de la maduración de los autofagosomas a autolisosomas a través de proteínas que unen el Ca2+ como las anexinas A1 y A5 y la copina 1. / Ghislat Cherfaoui, G. (2013). Regulation of Lysosomal Degradation by CA2+And CA2+-Binding Proteins [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/29690 / TESIS
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Targeting the formyl peptide receptor 1 for treatment of glioblastoma

Ahmet, Djevdet S. January 2021 (has links)
Background and Aims Gliomas account for over half of all primary brain tumours and have a very poor prognosis, with a median survival of less than two years. There is an urgent and unmet clinical need to develop new therapies against glioma. Recent reports have indicated the overexpression of FPR1 in gliomas particularly in high grade gliomas. The aim of this project was to identify and synthesise small molecule FPR1 antagonists, and to demonstrate a proof of principle in preclinical in vitro and in vivo models that small molecule FPR1 antagonism can retard expansion of glioma. Methods A number of small molecule FPR1 antagonists were identified by in silico design, or from the literature and then were prepared using chemical synthesis. FPR1 antagonists were evaluated in vitro for their ability to abrogate FPR1-induced cellular responses in a range of models including calcium mobilisation, cell migration, and invasion. The efficacy of FPR1 antagonist ICT12035 in vivo was assessed in a U-87 MG subcutaneous xenograft model. Results Virtual high throughput screening using a homology model of FPR1 led to the identification of two small molecule FPR1 antagonists. At the same time chemical synthesis of two other antagonists, ICT5100 and ICT12035 as well as their analogues were carried out. The FPR1 antagonists were assessed in calcium flux assay which gave an insight into their structure-activity relationship. Further investigation of both ICT5100 and ICT12035 demonstrated that both small molecule FPR1 antagonists were effective at abrogating FPR1-induced calcium mobilisation, migration, and invasion in U- 87 MG in vitro models in a dose-dependent manner. ICT12035 is a particularly selective and potent inhibitor of FPR1 with an IC50 of 37.7 nM in calcium flux assay. Additionally, it was shown that the FPR1 antagonist ICT12035 was able to arrest the growth rate of U-87 MG xenografted tumours in mice. Conclusion The results demonstrate that targeting FPR1 by a small molecule antagonist such as ICT12035, could provide a potential new therapy for the treatment of glioblastoma. / Yorkshire Cancer Research

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