Made available in DSpace on 2015-04-14T14:51:21Z (GMT). No. of bitstreams: 1 442974.pdf: 1168003 bytes, checksum: 61a64ae8027da7ef2e5ef378d8f25eb3 (MD5) Previous issue date: 2011-07-05 / Breast cancer is an important cause of morbidity and mortality in Brazil and worldwide. New therapeutic strategies have been proposed and one of them is the use of cell therapy with dendritic cells (DCs), however, the literature regarding the real benefit of this approach shows great variability and inability to produce a lasting immunity. In this paper we made a detailed characterization of monocyte-derived dendritic cells (MoDCs) of patients with breast cancer and monocytes that originated them. A lower yield of MoDCs was obtained from patients when compared to age matched healthy controls. Patient MoDCs exhibited decreased expressions of maturation and activation markers. Furthermore, cultures of MoDCs of patients had significantly elevated levels of spontaneous production of IL-6, which is consistent with a pro-tumor phenotype. These differences in molecule expression and cytokine production led us to postulate that the signaling pathways and / or the expression of toll like receptors (TLRs) could be altered. A decrease of TLR9 and TLR2 and an increase in the expression of NFkBp50 was found in MoDCs of patients without stimulation. After stimulation with LPS and CPG the patients did not upregulate expression of MyD88, suggesting a downregulation of the signaling pathways activated by these molecular patterns. The number of monocytes was also were decreased in patients, showing a reduced expression of GM-CSF receptors compared to monocytes of healthy controls. Cytokine production by monocytes from cancer patients was also altered, with an increased production of IL-6, IL-4 and IL-10. TLR2 and TLR9 expression was downregulated in monocytes of patients. Together these data show that monocytes are already altered in patients with cancer, and that will influence the phenotype of DCs differentiated from them. Tumor burden seems to induce a tolerogenic and pro-tumoral phenotype in patients?cells. This finding is important for the development of DC-based cancer immunotherapy. / A neoplasia mam?ria ? uma causa importante de morbidade e mortalidade no Brasil e no mundo. Novas estrat?gias terap?uticas vem sendo propostas e uma delas ? a utiliza??o de terapia celular com c?lulas dendr?ticas (DCs), entretanto, os dados da literatura em rela??o ao real benef?cio desta abordagem apresentam grande variabilidade e inabilidade em produzir uma imunidade duradoura. No presente trabalho fizemos uma caracteriza??o detalhada das c?lulas dendr?ticas derivadas de mon?citos (MoDCs) das pacientes com c?ncer de mama e dos mon?citos que as originaram. As MoDCs das pacientes s?o obtidas com um menor rendimento quando comparadas a controles saud?veis pareados por idade, e exibem uma diminui??o nos marcadores de matura??o e ativa??o. Al?m disso, as culturas de MoDCs das pacientes apresentaram altos n?veis de IL-6, o que ? compat?vel com um fen?tipo pr?-tumoral. Essas diferen?as na produ??o de citocinas nos levou a postular que as vias de sinaliza??o e/ou a express?o de toll like receptors (TLRs) poderiam estar alteradas. Observamos uma diminui??o de TLR9 e TLR2 e um aumento na express?o de NFkBp50 nas MoDCs das pacientes, sem est?mulo. Ap?s est?mulo com LPS e CPG as pacientes n?o aumentaram a express?o de MyD88, sugerindo uma diminui??o Ada via de sinaliza??o da resposta a esses padr?es moleculares. Quando analisamos os mon?citos, eles tamb?m estavam diminu?dos nas pacientes, e apresentavam uma express?o de receptores para GM-CSF inferior a dos controles saud?veis. A produ??o de citocinas pelos mon?citos das pacientes com c?ncer tamb?m estava alterada com uma produ??o aumentada de IL-6, IL-4 e IL-10. A frequ?ncia de TLR9 e TLR2 estava diminu?da nos mon?citos das pacientes. Esses dados conjuntamente demonstram que os mon?citos j? est?o alterados nas pacientes com c?ncer, assim como as DCs diferenciadas a partir deles. O crescimento tumoral parece induzir um fen?tipo de toler?ncia nestas c?lulas. Esse dado ? de fundamental import?ncia para o desenvolvimento de imunoterapia baseada em DCs.

Made available in DSpace on 2015-04-14T14:51:22Z (GMT). No. of bitstreams: 1 444924.pdf: 1000917 bytes, checksum: f4d5f486dd1a714bf1f2ecdcc7d68781 (MD5) Previous issue date: 2012-08-30 / I offer this thesis, which serves the purposes of the Programa de P?s-Gradu??o em Biologia Celular e Molecular, PUCRS and Coordena??o de Aperfei?oamento de Pessoal de N?vel Superiror (CAPES), in order to corroborate the routine practice in forensic genetics. Fired cartridge cases are commonly present in crime scenes with firearms and sometimes they are the only evidence available for the elucidation of a fact, which makes them investigation key players. To load a firearm the individual has to touch the ammunition, resulting in deposition of epithelial cells on the surface of the cartridges. However, in forensic genetic laboratories routine, DNA tests are not required for these signs as often as they are found. The reason for the underuse of these materials is the low concentration and high rate DNA degradation wich occurs due to overheating of the cartridge that can reach 1800oC. Besides that, the inhibition of PCR, few reports of success in obtaining genetic profiles from fired cases and the scarce verifying feasibility studies of these samples are factors that discourage this practice. In order to corroborate the genetic research routine, we have established a partnership between the sectors of Instituto Geral de Per?cias do Rio Grande do Sul (IGP/RS) Forensic Genetics and Ballistics and Laborat?rio de Gen?tica Humana e Molecular da PUCRS (LGHMPUCRS). The present study developed a controlled research to obtaining and analysis of nuclear DNA from fired cartridge cases. The study was based on standard protocols and/or indicated by the Forensic Science Department of Virginia. This study demonstrated that is possible to use fired, or not, cartridge cases as source of DNA to identify individuals who involved with its handle. However, considering the limited efficiency, the restricted effectiveness and the cost-benefit, means that the DNA analysis strategy from cells left in cartridges/cases is not priority in forensics lab routine. But, in many situations it could be the only option to investigators and, at this moment, our results and protocols herein will have main importance. This study concluded that following protocols here presented it is possible to produce data for human identification. The use of these protocols and their results will be definitive when used as an additional part of a police investigation and/or as evidence in criminal proceedings / Apresento esta disserta??o, a qual atende aos prop?sitos do Programa de P?s- Gradua??o em Biologia Celular e Molecular da PUCRS e da Coordena??o de Aperfei?oamento de Pessoal de N?vel Superiror (CAPES), com o prop?sito de corroborar com a rotina de pr?ticas em gen?tica forense. Estojos resultantes da deflagra??o de cartuchos s?o vest?gios comumente presentes em cenas de crime com armas de fogo e, por vezes, ?nicos ind?cios de que se disp?e para a elucida??o de um fato, o que os torna pe?as chave em uma investiga??o. Ao municiar uma arma de fogo ? necess?rio que o indiv?duo toque a muni??o, resultando na deposi??o de c?lulas epiteliais na superf?cie dos cartuchos. Entretanto, na rotina de laborat?rios de gen?tica forense, testes de DNA n?o s?o requeridos para estes ind?cios com tanta frequ?ncia quanto s?o encontrados. A justificativa para a subutiliza??o destes materiais ? a baixa concentra??o e a alta taxa de degrada??o do DNA, que ocorre devido ao superaquecimento do cartucho que pode chegar a 1800oC, al?m disso, a inibi??o da PCR, os poucos relatos de sucesso na obten??o de perfil gen?tico a partir de estojos deflagrados e os ex?guos estudos que verificam a viabilidade de amostras como estas, s?o fatores que desestimulam esta pr?tica. Com o intuito de corroborar com a rotina de investiga??o gen?tica, estabeleceu-se uma parceria entre os Setores de Gen?tica Forense e de Bal?stica Forense do Instituto-Geral de Per?cias do Rio Grande do Sul (IGP/RS) e o Laborat?rio de Gen?tica Humana e Molecular da Faculdade de Bioci?ncias da Pontif?cia Universidade Cat?lica do Rio Grande do Sul (LGHMPUCRS). O presente estudo desenvolveu uma pesquisa controlada para obten??o e an?lise de DNA nuclear oriundos de estojos de cartuchos deflagrados. O estudo de foi realizado adaptando-se protocolos padr?o e/ou indicados pelo Departamento de Ci?ncias Forenses da Virg?nia. Este estudo demonstrou que ? poss?vel utilizar estojos deflagrados ou n?o, como fonte de DNA com a finalidade de identificar os envolvidos com o seu manuseio. Contudo, considerando o rendimento limitado, a efic?cia restrita e, sobretudo, o custo-benef?cio, entende-se que a estrat?gia de an?lise de DNA oriundo de c?lulas deixadas em cartuchos/estojos n?o seja a priorit?ria na rotina do Laborat?rio Forense. Mas, em muitas situa??es, essa pode ser a ?nica op??o dos investigadores e, nesse momento, nossos resultados e protocolos aqui apresentados ter?o import?ncia fundamental. Com este estudo conclu?mos que seguindo os protocolos aqui apresentados ? poss?vel produzir dados para fins de identifica??o humana. O uso destes protocolos, e de seus resultados, poder? ser definitivo quando usados como elemento adicional de um inqu?rito policial e/ou como prova em um processo penal

Made available in DSpace on 2015-04-14T14:51:22Z (GMT). No. of bitstreams: 1 445049.pdf: 985835 bytes, checksum: 6999f9525f1cf085ddde3a6a0fb67e0b (MD5) Previous issue date: 2012-10-31 / The presence of Bacillus spp. in milk is an important problem for the dairy industry due to their capability of sporulation and the possibility of spore resistance to heat treatment by ultra high temperature (UHT). Bacillus sporothermodurans survive to the UHT system, germinating and growing in stored milk and, if not correctly identified and quantified, can exceed the criterion established for mesophilic aerobic, besides altering the quality of dairy products when in high concentrations. On the other hand, contamination of milk by Bacillus cereus is not only an important cause of deterioration, but is also associated with the occurrence of diarrhea and emetic syndromes. Traditionally, these microorganisms are identified and quantified in food using conventional microbiological techniques, but the Polymerase Chain Reaction (PCR) based methods have been widely used for the same purpose. However, PCR cannot distinguish between viable and dead cells, which can be overcame with the use of DNA intercalating, such as propidium monoazide (PMA). PMA binds to DNA derived from cells with damaged membranes, preventing their amplification by PCR, allowing, thus, the selective detection of viable cells. Therefore, this thesis aimed to characterize the thermal resistance of B. sporothermodurans and to develop methods of detection and quantificatification of viable cells of B. sporothermodurans and B. cereus in milk samples by qPCR associated with PMA. Isothermal and non-isothermal treatments allowed the determination of the profile of heat resistance of B. sporothermodurans spores to heat UHT process, predicting that to 121?C was found a D value between 2 a 4 min. The selective detection and quantification of B. sporothermodurans and B. cereus by PMA-qPCR were developed targeting 16S rRNA gene and hemolysin gene, respectively.The treatment with PMA from pure culture and artificially contaminated UHT milk were standardized by end-point PCR for the detection of viable cells of these microorganisms. The inhibition of amplification of DNA from dead cells was obtained at a concentration of 30μg/mL PMA. The standardization of qPCR assays were performed using hydrolysis probes (TaqMan? system) specific to each target gene. The quantification limit from UHT milk artificially contaminated was 2.5 x 102 CFU/mL for B. sporothermodurans and 7.5 x 102 CFU/mL for B. cereus. The assays were applied to 135 samples of UHT milk of different commercial brands, comparing with the conventional method of cultivation for each microorganism. B. sporothermodurans and B. cereus were respectively detected in 14 (10.4%) and 44 (32.6%) of the samples by molecular methods developed, and in 11 (8.1%) and 15 (11.1%) by conventional culturing methods. The PMA-qPCR methods developed in this study were specific and sensitive for the detection and quantification of viable B. sporothermodurans and B. cereus cells, being applicable for the evaluation of milk samples, reducing the time for the analysis of this product. Furthermore, the results showed that B. cereus can be found in UHT milk / A presen?a de Bacillus spp. em leite representa um importante problema para a ind?stria de latic?nios devido ? sua capacidade de esporula??o e ? possibilidade de resist?ncia do esporo ao tratamento t?rmico por ultra alta temperatura (UAT). O Bacillus sporothermodurans sobrevive ao sistema UHT, germinando e se multiplicando no leite estocado e, caso n?o seja corretamente quantificado e identificado, pode ultrapassar o limite estabelecido pela legisla??o para microrganismos mes?filos aer?bios, al?m de alterar a qualidade dos produtos l?cteos quando em altas concentra??es. Por outro lado, a contamina??o de leite por Bacillus cereus constitui n?o somente uma importante causa de deteriora??o, mas tamb?m est? associada com a ocorr?ncia das s?ndromes em?tica e diarreica. Tradicionalmente, estes microrganismos s?o identificados e quantificados em alimentos atrav?s de t?cnicas cl?ssicas de cultivo, mas m?todos baseados na Rea??o em Cadeia pela Polimerase (PCR) tamb?m t?m sido amplamente utilizados. Entretanto, a PCR n?o distingue c?lulas mortas de c?lulas vi?veis, o que pode ser contornado com o emprego de intercalantes de DNA, como o prop?dio monoazida (PMA). O PMA se liga ao DNA derivado de c?lulas com membranas rompidas, impedindo suas amplifica??es na PCR, permitindo, assim, a detec??o seletiva de c?lulas vi?veis. Portanto, a presente tese teve por objetivo caracterizar a resist?ncia t?rmica de B. sporothermodurans, bem como desenvolver m?todos de detec??o e quantifica??o de c?lulas vi?veis de B. sporothermodurans e de B. cereus em amostras de leite atrav?s de PCR associada ao PMA. Tratamentos isot?rmicos e n?o isot?rmicos permitiram a determina??o do perfil de resist?ncia t?rmica de esporos de B. sporothermodurans ao processo UHT, predizendo que a 121?C foi encontrado um valor D entre 2 a 4 min.A detec??o e quantifica??o seletivas de B. sporothermodurans e de B. cereus atrav?s de PMA-qPCR foram desenvolvidas utilizando o gene RNAr 16S e o gene da hemolisina como alvos, respectivamente. O tratamento com PMA a partir de cultura pura e leite UHT artificialmente contaminado foi padronizado atrav?s da PCR convencional para a detec??o de c?lulas vi?veis destes microrganismos. A inibi??o da amplifica??o de DNA de c?lulas mortas foi obtida na concentra??o de 30μg/mL de PMA. A padroniza??o dos ensaios de qPCR foram realizados utilizando sondas de hidr?lise (sistema TaqMan?) espec?ficas para cada gene alvo. O limite de quantifica??o a partir de leite UHT artificialmente contaminado foi de 2,2 x 102 UFC/mL para B. sporothermodurans e de 7,5 x 102 UFC/mL para B. cereus. As t?cnicas foram aplicadas a 135 amostras de leite UHT de diferentes marcas comerciais, comparando com a metodologia cl?ssica de cultivo para cada microrganismo. B. sporothermodurans e B. cereus foram, respectivamente, detectados em 14 (10,4%) e 44 (32,6%) das amostras analisadas pelos m?todos moleculares desenvolvidos, e em 11 (8,1%) e 15 (11,1%) pelos m?todos convencionais de cultivo. Os m?todos de PMA-qPCR desenvolvidos neste estudo foram espec?ficos e sens?veis para a detec??o e quantifica??o de c?lulas vi?veis de B. sporothermodurans e de B. cereus, mostrando-se aplic?veis para serem utilizados na avalia??o de amostras de leite, reduzindo o tempo de an?lise deste produto. Al?m disso, os resultados demonstraram que B. cereus pode ser encontrado em leite tratado pelo sistema de UHT

Made available in DSpace on 2015-04-14T14:51:22Z (GMT). No. of bitstreams: 1 447381.pdf: 1128253 bytes, checksum: d5ebf0da0d18404190c4e67763e48457 (MD5) Previous issue date: 2013-03-06 / Sepsis, a medical condition that affects 18 million people per year worldwide, is characterized by a generalized inflammatory state caused by infection. The widespread activation of coagulation pathways and inflammation progresses to multiple organ failure, the collapse of the circulatory system (septic shock) and death. Despite decades of research and numerous clinical trials, little progress has been made in developing new treatments and mortality rates are virtually the same in the last 20 to 30 years. As such, sepsis remains a difficult opponent for surgeons and their patients, so the search for new therapeutic alternatives becomes strictly essential. Recently stem cells have emerged as a promising therapy for a variety of diseases, including cardiovascular diseases, neurodegenerative disorders, peripheral vascular disease, renal disease, and several others. Its beneficial effects are due mainly to their ability to connect to injury and inflammation, to attenuate the inflammatory response, and accelerate tissue healing and neoangiogenesis due to noxious stimuli. Considering this therapeutic potential, this study aimed to evaluate whether these cells could lead to immune response back into balance, reducing the pathophysiology of sepsis and thereby increase the survival time in mice using an experimental model of sepsis. Our results demonstrated that treatment with mesenchymal stem cells was able to increase survival time of the animals that were tested. This effect is due to the ability of these cells to modulate the immune response providing a smaller reduction in tissue injury and apoptotic cells. These findings demonstrate that mesenchymal stem cells have therapeutic potential and can function as a possible future treatment for sepsis. / Sepse, uma condi??o m?dica que afeta 18 milh?es de pessoas por ano no mundo, ? caracterizada por um estado inflamat?rio generalizado causado por uma infec??o. A ativa??o generalizada de vias de coagula??o e inflama??o evolui para disfun??o de m?ltiplos ?rg?os, o colapso do sistema circulat?rio (choque s?ptico) e morte. Apesar de d?cadas de pesquisas e numerosas experimenta??es cl?nicas, pouco progresso tem sido observado no desenvolvimento de novos tratamentos e as taxas de mortalidade s?o praticamente as mesmas nos ?ltimos 20 a 30 anos. Como tal, a sepse continua sendo um dif?cil advers?rio para cirurgi?es e seus pacientes, logo, a busca por novas alternativas terap?uticas torna-se estritamente essencial. Recentemente as c?lulas-tronco t?m emergido como uma terapia promissora para uma variedade de patologias, incluindo doen?as cardiovasculares, neurodegenerativas, doen?a vascular perif?rica, doen?a renal, e v?rias outras. Seus efeitos ben?ficos est?o relacionados principalmente ?s suas capacidades de se conectarem a les?es e inflama??es, para atenuar a resposta inflamat?ria e acelerar a cicatriza??o de tecidos e de neoangiog?nese devido a est?mulos nocivos. Considerando esse potencial terap?utico, o presente estudo teve por objetivo avaliar se essas c?lulas poderiam conduzir a resposta imune de volta ao equil?brio, atenuando a fisiopatologia da sepse e dessa forma aumentando o tempo de sobrevida em camundongos, utilizando um modelo de sepse experimental. Os resultados demonstraram que o tratamento com as c?lulas-tronco mesenquimais foi capaz de aumentar o tempo de sobrevida dos animais em estudo. Esse efeito observado deve-se ? capacidade destas c?lulas de modularem a resposta imune, proporcionando uma menor les?o tecidual e a diminui??o de c?lulas apopt?ticas. Essas descobertas demonstram que as c?lulas-tronco mesenquimais t?m potencial terap?utico e podem funcionar futuramente como um poss?vel tratamento para a sepse.

Made available in DSpace on 2015-04-14T14:51:23Z (GMT). No. of bitstreams: 1 447382.pdf: 4486344 bytes, checksum: 86fdbbba27db00743c8e29d0d264ba0e (MD5) Previous issue date: 2013-03-06 / A wide variety of studies have demonstrated that physical activity has beneficial effects on brain function, including the improvement of cognition, the enhancement of learning and memory processes, and also displays neuroprotective effects. One of the mechanisms responsible for these beneficial effects is the influence that exercise has on brain plasticity. In this sense, the hippocampus is a brain region particularly important in the formation of new memories and featured as one of the main structures of the brain where we observe neurogenesis in adulthood. The astrocytes are important glial cells, critical for neuronal energy metabolism by regulating the concentration of various molecules and as neurons, are believed to participate actively in the synaptic function. Furthermore, astrocytes are susceptible to plasticity induced by environmental stimuli such as physical exercise. The aim of this study was to investigate whether physical exercise can alter the immunoreactivity for Glial Fibrillary Acidic Protein (GFAP), density and morphology of GFAP positive astrocytes, in the stratum radiatum of the CA1 region of the rat hippocampus. Thirteen male rats were divided in two groups: Sedentary (n=6) and Exercise (n=7). The animals in the exercise group were submitted to a protocol of 30 minutes of daily physical exercise on a treadmill for 4 consecutive weeks. GFAP immunoreactivity was evaluated using optical densitometry and the analysis of the astrocyte ramification was done using an adaptation of Sholl's concentric circles method. The results show that physical exercise is capable of increasing the density of GFAP positive astrocytes as well as the regional and cellular GFAP expression. In addition, physical exercise altered astrocytic morphology as shown by the increased degree of ramification observed in the lateral quadrants and in the length of the longest astrocytic processes in the central quadrants. This data demonstrate important changes in astrocytes promoted by physical exercise, supporting the idea that these cells are involved in regulating neural activity and plasticity. / Diversos estudos demonstram que a pr?tica de atividade f?sica di?ria tem efeitos ben?ficos sobre a fun??o cerebral, incluindo melhora da cogni??o e dos processos de aprendizagem e mem?ria, al?m de apresentar efeitos neuroprotetores. Um dos mecanismos respons?veis por esses efeitos ben?ficos ? a influ?ncia que o exerc?cio f?sico exerce sobre a plasticidade neural. Neste sentido, o hipocampo ? uma regi?o encef?lica especialmente importante nos processos de forma??o de novas mem?rias e caracterizado como um dos principais locais do enc?falo onde observamos neurog?nese em fase adulta. Os astr?citos s?o importantes c?lulas da glia, fundamentais para o metabolismo energ?tico neuronal, regulando a concentra??o de v?rias mol?culas e assim como os neur?nios, acredita-se que participem ativamente da fun??o sin?ptica. Al?m disso, os astr?citos s?o c?lulas suscet?veis ? plasticidade induzida por est?mulos ambientais, como o exerc?cio f?sico. O objetivo deste estudo foi investigar se o exerc?cio f?sico ? capaz de alterar a imunorreatividade para a Prote?na Glial Fibrilar ?cida (GFAP), a densidade e a morfologia dos astr?citos GFAP positivos, do stratum radiatum da regi?o CA1 do hipocampo de ratos Wistar. Treze ratos machos foram divididos em 2 grupos: Sedent?rio (n=6) e Exerc?cio (n=7). Os animais do grupo exerc?cio foram submetidos a 4 semanas de exerc?cio f?sico di?rio em esteira durante 30 minutos por dia. A imunorreatividade para GFAP foi avaliada por densitometria ?ptica e a an?lise da ramifica??o astrocit?ria foi realizada por uma adapta??o do m?todo dos c?rculos conc?ntricos de Sholl. Os resultados obtidos demonstram que o exerc?cio f?sico foi capaz de aumentar a densidade de astr?citos GFAP positivos, bem como a express?o regional e celular de GFAP. Al?m disso, os astr?citos alteraram sua morfologia em resposta ao exerc?cio f?sico, o que foi demonstrado pelo aumento no grau de ramifica??o dos astr?citos nos quadrantes laterais e no comprimento dos processos astroc?ticos nos quadrantes centrais. Estes achados demonstram importantes altera??es astrocit?rias ap?s o exerc?cio f?sico, corroborando a ideia de que estas c?lulas est?o envolvidas na regula??o da atividade neural e da plasticidade.

Made available in DSpace on 2015-04-14T14:51:23Z (GMT). No. of bitstreams: 1 447380.pdf: 675913 bytes, checksum: bfb87e6d734478e3c7bb6275c3132761 (MD5) Previous issue date: 2013-02-26 / Liver fibrosis is the wound healing response to repeated injury of the liver. It is characterized by disruption of the liver architecture associated with increased expression of extracellular matrix components. Hepatic stellate cells (HSC) play a key role in liver fibrogenesis. In normal liver, HSC are quiescent and its main function is to store vitamin A. During liver injury, these cells undergo activation, become myofibroblasts and acquire fibrogenic properties. Activation of PPARγ (peroxisome proliferator-activated receptor gamma) and inhibition of fibrogenic molecules are potential strategies to block HSC activation and differentiation. Aware that the process of hepatic fibrosis involves inflammatory mediators, various anti-inflammatory substances have been studied in an attempt to revert fibrosis. The purpose of this study was to investigate the in vitro effects of fructose-1,6-bisphospahte (FBP) on HSC phenotype. The results demonstrated that FBP induced quiescent phenotype in HSC via PPARγ activation. Significant decrease in type I collagen mRNA expression was observed in the first 24h of treatment. These events preceded the reduction of TGF-β1 (transforming growth factor-beta) and total collagen secretion. Thus, FBP promoted downregulation of HSC activation by its antifibrotic and anti-inflammatory actions. These findings demonstrate that FBP may have potential as a novel therapeutic agent for the treatment of liver fibrosis. / A fibrose hep?tica ? a resposta cicatricial do f?gado a les?es continuadas, caracterizada pelo rompimento da arquitetura hep?tica associada ao aumento da express?o dos componentes da matriz extracelular. As c?lulas estreladas hep?ticas (HSC) desempenham um papel fundamental no processo de fibrog?nese. No f?gado normal, as HSC encontram-se em sua forma quiescente de dep?sito de vitamina A. Durante a les?o hep?tica, essas c?lulas passam por uma ativa??o fenot?pica, tornam-se miofibroblastos e adquirem propriedades fibrog?nicas. O processo de fibrose hep?tica envolve v?rios mediadores inflamat?rios e, portanto, subst?ncias anti-inflamat?rias tem sido empregadas na tentativa de reverter a fibrose e bloquear a ativa??o e diferencia??o das HSC. A ativa??o de PPARγ (receptor ativado por proliferador de peroxissomo Gama) e a inibi??o de mol?culas fibrog?nicas s?o poss?veis estrat?gias para estes fins. O objetivo deste estudo foi investigar os efeitos in vitro da frutose-1,6-bisfosfato (FBP) sobre o fen?tipo das HSC. Os resultados demonstraram que a FBP ? capaz de induzir o fen?tipo quiescente das HSC via ativa??o de PPARγ. Foi observado nas primeiras 24h de tratamento uma diminui??o significativa da express?o de mRNA de col?geno tipo I. Posteriormente, houve uma redu??o do col?geno total e de TGF-β1 (fator de transforma??o do crescimento beta). Assim, a FBP diminui o estado de ativa??o das HSC por suas a??es antifibr?ticas e anti-inflamat?rias. Estas descobertas demonstram que a FBP pode ser um potencial novo agente terap?utico para o tratamento de fibrose hep?tica.

Made available in DSpace on 2015-04-14T14:51:23Z (GMT). No. of bitstreams: 1 447376.pdf: 1656350 bytes, checksum: c0a2b1db197a97d3100dfa1ffa101f1f (MD5) Previous issue date: 2012-12-26 / Benzodiazepines, such as diazepam and midazolam, are a widely used class of drugs for anxiety treatment, with anxiolytic, hypnotic, and anticonvulsant properties. The use of zebrafish (Danio rerio) as a model for evaluating pharmacological mechanisms has gained importance due to their rapid development and high sensitivity to drugs. Studies have shown that behavioral parameters were altered in zebrafish after benzodiazepine treatment. Many neurotransmitter systems have been identified in this species, including purinergic and cholinergic system. Purinergic system is characterized by the action of ATP and adenosine on purinoreceptor P2 and P1, respectively. The levels of these molecules are regulated by ectonucleotidases, especially nucleoside triphosphate diphosphohydrolase (NTPDases) and ecto-5'-nucleotidase, which constitute the extracellular cascade for ATP hydrolysis to adenosine. Adenosine can be subsequently deaminated to inosine by action of adenosine deaminase (ADA). ATP is coreleased with other neurotransmitters, including acetylcholine, and has been demonstrated that adenosine can control the release of acetylcholine. Cholinergic system is characterized by the action of acetylcholine (ACh) on muscarinic and nicotinic receptors. The level of this molecule is regulated by acetylcholinesterase (AChE), which catalyzes degradation of ACh into choline and acetate. Since there are few reports relating these enzyme activities and the action mechanism of benzodiazepines, the aim of this study was evaluated the in vitro and ex vivo effects of classical benzodiazepines, such as diazepam and midazolam, on NTPDase, ecto-5'nucleotidase, ADA, and AChE activities in zebrafish brain and gene expression pattern in treatments that induced changes in enzyme activity in the ex vivo experiments. In order to elucidate whether diazepam or midazolam has direct effects on these enzymes, we performed in vitro experiments. Diazepam, at 500 μM, promoted a decrease on ATP hydrolysis (66%), whereas this drug, at 10-500 μM, reduced ADP hydrolysis (40-54%, respectively). Midazolam also decreased ATP (16-71% for 10-500 μM, respectively) and ADP hydrolysis (48-73% for 250-500 μM, respectively), and ecto-ADA activity (26-27.5% for 10-500 μM, respectively). Diazepam and midazolam did not induce significant changes on ecto-5?-nucleotidase activity at the concentrations tested. Concerning to AChE activity, 500 μM diazepam promoted a decrease on ACh hydrolysis (19%), whereas midazolam, at 50-500 μM, reduced AChE activity (18-79%, respectively). For ex vivo experiments, diazepam or midazolam exposures did not alter NTPDase activities in zebrafish brain membranes. AMP hydrolysis was decreased in animals treated with of 0.5 and 1mg/L midazolam (31.5% and 36.1%, respectively) when compared to the control group. However, diazepam was unable to alter ecto-5 -nucleotidase. Both drugs significantly decreased the ecto-ADA activity, whereas diazepam and midazolam reduced the adenosine hydrolysis at a concentration of 1.25 mg/L (30.85%) and 1 mg/L (32.8%), respectively. Diazepam did not alter cytosolic-ADA activity; however, the exposure to 0.1 mg/L midazolam induced a significant increase in cytosolic-ADA (39.9%) when compared with the control group. The gene expression pattern demonstrated that the CD73 transcript levels were increased (41.7%) after treatment with 0.5 mg/L midazolam. Moreover, the changes caused by diazepam and midazolam in the ADA activity are not related to the transcriptional control. Concerning the cholinerg signaling, diazepam decreased ACh hydrolysis at 1.25 mg/L (30.7%) when compared to the control group. Similarly, the exposure to 0.5 mg/L midazolam also changed the enzymatic activity of AChE promoting an increase in the ACh hydrolysis (36.7%). It is possible to suggest that these drugs can induce a direct effect on the enzyme activities, since we observed a decreased on nucleotide and nucleoside hydrolysis after in vitro exposure. In addition, the alteration on AMP hydrolysis, ADA and AChE activities suggest a modulation of extracellular adenosine and ACh levels induced by benzodiazepine exposure. / F?rmacos benzodiazep?nicos, como diazepam e midazolam, s?o muito usados na pr?tica cl?nica para o tratamento da ansiedade, possuindo propriedades ansiol?ticas, hipn?ticas e anticonvulsivantes. O uso do zebrafish (Danio rerio) como modelo para avaliar mecanismos farmacol?gicos tem ganhado grande import?ncia devido ao r?pido desenvolvimento e alta sensibilidade a drogas que essa esp?cie possui. Estudos t?m demonstrado que par?metros comportamentais mostraram-se alterados em zebrafish ap?s tratamento com benzodiazep?nicos. Muitos sistemas de neurotransmiss?o foram identificados nessa esp?cie, incluindo os sistemas purin?rgico e colin?rgico. O sistema purin?rgico ? caracterizado pela a??o do ATP e adenosina (ADO) nos purinoreceptores P2 e P1, respectivamente. Os n?veis dessas mol?culas s?o regulados pela a??o das ectonucleotidases, especialmente as nucleos?deo trifosfato difosfoidrolases (NTPDases) e a ecto-5 -nucleotidase, que catalisam a hidr?lise do ATP a adenosina. A adenosina pode ser desaminada a inosina pela a??o da adenosina desaminase (ADA). O ATP ? coliberado com outros neurotransmissores, entre eles a acetilcolina, e tem sido demonstrado que a adenosina pode controlar a libera??o de acetilcolina. O sistema colin?rgico ? caracterizado pela a??o da acetilcolina (ACh) nos receptores muscar?nicos e nicot?nicos. O n?vel dessa mol?cula ? regulado pela acetilcolinesterase (AChE), que catalisa a degrada??o da ACh em colina e acetato. Uma vez que existem poucos relatos relacionando esses sistemas enzim?ticos e a a??o de f?rmacos benzodiazep?nicos, o objetivo deste estudo foi avaliar o efeito in vitro e ex vivo do tratamento com f?rmacos benzodiazep?nicos, tais como diazepam e midazolam, sobre a atividade das NTPDases, ecto-5'-nucleotidase, ADA and AChE no enc?falo de zebrafish e o padr?o de express?o g?nica nos tratamentos que induziram altera??es na atividade enzim?tica nos experimentos ex vivo. A fim de elucidar se o diazepam e o midazolam t?m efeitos diretos nessas enzimas, experimentos in vitro foram realizados. Na concentra??o de 500 μM, o diazepam diminuiu a hidr?lise de ATP (66%) e, nas concentra??es de 10-500 μM, este f?rmaco reduziu a hidr?lise de ADP (40-54%, respectivamente). O midazolam tamb?m diminuiu a hidr?lise do ATP (16-71% para 10-500 μM, respectivamente), ADP (48-73% para 250-500 μM, respectivamente) e a atividade da ecto-ADA (26-27,5% para 10-500 μM, respectivamente). Diazepam e midazolam n?o induziram altera??es significativas sobre a atividade da ecto-5?-nucleotidase nas concentra??es testadas. Com rela??o ? atividade da AChE, o diazepam, 500 μM, promoveu uma diminui??o na hidr?lise de ACh (19%) e o midazolam, nas concentra??es de 50-500 μM, reduziu a atividade da AChE (18-79%, respectivamente). Nos experimentos ex vivo, as exposi??es ao diazepam e midazolam n?o alteraram a atividade enzim?tica das NTPDases em membranas cerebrais de zebrafish. A hidr?lise do AMP diminuiu em animais tratados com 0.5 mg/L e 1 mg/L de midazolam (31.5% e 36.1%, respectivamente) quando comparados com o grupo controle. Entretanto, o diazepam foi incapaz de alterar a atividade da ecto-5 -nucleotidase. Ambos os f?rmacos diminu?ram significativamente a atividade da ecto-ADA, sendo que o diazepam e o midazolam reduziram a hidr?lise da adenosina na concentra??o de 1.25 mg/L (30.85%) e 1 mg/L (32.8%), respectivamente. O diazepam n?o alterou a atividade da ADA citos?lica, no entanto a exposi??o a 0.1 mg/L de midazolam induziu um significativo aumento na atividade dessa enzima (39.9%) quando comparado ao grupo controle. O padr?o de express?o g?nica demonstrou que os n?veis de transcritos do CD73 apresentaram-se reduzidos (41,7%) ap?s o tratamento com 0.5 mg/L de midazolam. Com rela??o a sinaliza??o colin?rgica, diazepam diminuiu a hidr?lise da ACh na concentra??o de 1.25 mg/L (30.7%) quando comparado ao grupo controle. Similarmente, a exposi??o ? concentra??o de 0.5 mg/L de midazolam tamb?m alterou a atividade enzim?tica da AChE, promovendo um aumento na hidr?lise da ACh (36.7%). ? poss?vel sugerir que essas drogas podem induzir um efeito direto na atividade enzim?tica, uma vez que foi observada uma diminui??o na hidr?lise de nucleot?deos e nucleos?deos ap?s a exposi??o in vitro. Al?m disso, as altera??es na hidr?lise do AMP e atividade da ADA e da AChE sugerem uma modula??o dos n?veis extracelulares de adenosina e acetilcolina induzidos pela exposi??o aos f?rmacos benzodiazep?nicos.

Made available in DSpace on 2015-04-14T14:51:23Z (GMT). No. of bitstreams: 1 447525.pdf: 8523375 bytes, checksum: f1de0a2db10e3435b1a38c1f14c98be9 (MD5) Previous issue date: 2012-11-28 / Periodontitis has a bacterial etiology associated with the presence of a susceptible host. Immunogenetics factors have been studied in an attempt to explain the more aggressive disease, to establish diagnosis and to determine a more reliable prognosis. The present study had as objectives to evaluate the HLA-G polymorphisms (14 bp insertion/deletion and C/G +3142) and the cytokines profile (Th1 and Th2) in patients with chronic periodontitis, aggressive periodontitis and healthy controls. In relation to the 14 bp polymorphism, in chronic periodontitis patients, it was observed a significant increase in homozygous frequency for the deletion allele, when compared to controls. This same group presented a higher frequency of this allele, which was marginally not significant. Furthermore, no significant difference was observed between aggressive periodontitis patients and controls in relationship to the polymorphisms of 14 bp and C/G +3142.When haplotypes were estimated, an increased frequency of the deletion/G and decreased of the insertion/G was observed in chronic periodontitis patients compared to controls, but with no statistical difference. When evaluating serum cytokines concentration (IL-2, IL-4, IL-5, IL-10, TNF-α and IFN-γ), although no statistical difference could be seen between groups, a tendency to lower levels of IL-5 and IL-10 in aggressive periodontitis group was observed. Our results suggest that having HLA-G homozygosis for the deletion allele, yields three more times chance to present chronic periodontitis (OR = 3.07, 95% CI: 1.24-7.87), inferring a susceptibility role of this polymorphism in the pathogenesis of this condition. Yet considering the cytokine profiles, the aggressive periodontitis patients presented a tendency towards the Th2 profile, suggesting a contribution to the development of this exacerbated manifestation of the disease / A periodontite apresenta etiologia bacteriana associada ? presen?a de um hospedeiro suscet?vel. Fatores imunogen?ticos t?m sido estudados para tentar explicar as formas mais agressivas da doen?a, estabelecer um diagn?stico precoce e definir um progn?stico mais confi?vel. O presente estudo teve como objetivos avaliar os polimorfismos do gene HLA-G (inser??o e dele??o de 14 pb e C/G +3142) e o perfil de citocinas (Th1 e Th2) em pacientes com periodontites cr?nica, periodontite agressiva e controles saud?veis. Em rela??o ao polimorfismo de 14 pb foi observado, nos pacientes com periodontite cr?nica, um aumento significante na frequ?ncia de homozigotos para o alelo de dele??o, quando comparados aos controles. Este mesmo grupo apresentou a maior frequ?ncia deste alelo, o que foi marginalmente n?o significante. Al?m disso, nenhuma diferen?a significativa foi observada entre os pacientes com periodontite agressiva e os controles em rela??o aos polimorfismos de 14 pb e C/G +3142.Quando os hapl?tipos foram estimados, uma frequ?ncia aumentada do dele??o/G e diminu?da do inser??o/G foi observada nos pacientes com periodontite cr?nica comparados aos controles, mas sem diferen?a estat?stica. Com rela??o ? concentra??o s?rica de citocinas (IL-2, IL-4, IL-5, IL-10, TNF-α e IFN-γ), n?o foi verificada diferen?a significativa entre os grupos estudados, embora os achados revelaram uma tend?ncia a menores n?veis de IL-5 e IL-10 no grupo com periodontite agressiva. Nossos resultados sugerem em rela??o ao HLA-G, que os pacientes homozigotos para o alelo de dele??o, t?m 3 vezes mais chance de apresentar periodontite cr?nica (OR = 3.07, 95% CI: 1.24-7.87), inferindo um papel de suscetibilidade deste polimorfismo na patog?nese desta condi??o. J? os pacientes com periodontite agressiva, quando avaliados em rela??o ao perfil de citocinas, apresentaram uma tend?ncia direcionada ao perfil Th2, sugerindo uma contribui??o para o desenvolvimento da manifesta??o exacerbada da doen?a

Made available in DSpace on 2015-04-14T14:51:25Z (GMT). No. of bitstreams: 1 448604.pdf: 1148296 bytes, checksum: ca8ff4b1f0199484ac8c3e8b70d970b8 (MD5) Previous issue date: 2013-03-05 / According to data from the World Health Organization (WHO), stress affects more than 90% of the world's population and is considered a global epidemy. Stress has become an integral part of human life and organisms are constantly subjected to stressful stimuli that change various physiological processes, representing a risk factor for many diseases, such as cancer, cardiovascular, metabolic, infectious and gastrointestinal deseases and depression. The zebrafish (Danio rerio) has many similarities with mammalian in terms of overall organization and the functioning of their stress regulatory systems. The zebrafish hypothalamic-pituitary-interrenal (HPI), analogous to the mammalian hypothalamic-pituitary-adrenal (HPA), has been found in zebrafish and the activation of this pathway is essential for the maintenance of vital functions in response to stressful events. Despite extensive knowledge regarding stress responses in mammals, data on the relationship between chronic unpredictable stress and its effects on purinergic signaling is limited. Purinergic signaling is mediated by ATP and adenosine receptor activation through P2 and P1, respectively. The catabolism of extracellular ATP to adenosine is promoted by the ectonucleotidases, such as Ecto-nucleoside triphosphate diphosphohydrolases (E-NTPDases) and ecto-5 '-nucleotidases (E-5?NT). Adenosine is deaminated by adenosine deaminase (ADA) producing inosine. Thus, these enzymes control the levels of extracellular nucleotides and nucleosides, exerting an influence on purinergic signaling. Considering some models of stress can affect the signalling systems, the objective of this study was to verify whether the unpredictable chronic stress changes ectonucleotidases and adenosine deaminase activities in zebrafish brain. In addition, we analyzed the metabolism of ATP as well as the expression of genes related to ADA, ada1, ada2.1, ada2.2, adaL, adaasi and the effects of agonists and antagonists of adenosine receptors in an unpredictable chronic stress model in zebrafish. Our results demonstrated that there are no changes on ATP (P = 0.1499), ADP (P = 0.3615) and AMP (P = 0.8987) hydrolysis in zebrafish brain membranes submitted to unpredictable chronic stress. In contrast, ecto-ADA activity significantly decreased (26.8%; 8,164 ? 0.78 NH3 min &#8722; 1 mg&#8722; 1 of protein; p 0.05; n = 5 <) in brain membranes of animals exposed to the unpredictable chronic stress when compared to the control group (11.15 ? 2.16 NH3 min &#8722; 1 mg &#8722; 1 of protein; p 0.05; n = 5). However, the activity of cytosolic ADA was not changed after the unpredictable chronic stress. Quantitative analysis by RT-qPCR did not show significant changes after chronic unpredictable stress exposure on gene expression in the genes ada1, ada2.1, ada2.2, adaL, adaasi. ATP metabolism in brain membrane preparations of zebrafish in the control group and stressed was measured by high-performance liquid chromatography (HPLC) and showed a significant increase of adenosine in stressed animals. Considering adenosine A1 receptor agonists have an anxyolitic activity and the A2A receptor antagonists can exert neuroprotective effects, we investigated the effect of administration of an agonist of A1 receptor, N&#8310;-ciclopentiladenosine (CPA), and an antagonist of A2A receptors, (ZM241385) on behavioral parameters of animals submitted to unpredictable chronic stress to check a possible relationship between the adenosinergic system and the stress. As a result we showed that these compounds have not been able to reverse the anxiogenic effect caused by unpredictable chronic stress. Since adenosine has neuromodulatory and anxiolytic effects, changes in its levels could play a role in counteracting the stress, which could be related to a compensatory mechanism in order to restore the homeostasis. / De acordo com dados da Organiza??o Mundial de Sa?de (OMS), atualmente o estresse afeta mais de 90% da popula??o mundial, sendo considerado uma epidemia global. O estresse tornou-se parte integrante da vida humana e os organismos s?o constantemente submetidos a est?mulos estressantes que alteram v?rios processos fisiol?gicos, sendo um fator de risco para diversas patologias, como c?ncer, doen?as cardiovasculares, metab?licas, infecciosas, gastrointestinais e depress?o. O peixe-zebra (Danio rerio) tem muitas semelhan?as com mam?feros em termos de organiza??o geral e o funcionamento dos respectivos sistemas reguladores do estresse. O eixo hipot?lamo-pituit?ria-interrenal (HPI), um sistema an?logo ao eixo hipot?lamo-pituit?ria-adrenal (HPA), foi descrito em zebrafish e a ativa??o desta via ? essencial para a manuten??o das fun??es vitais como resposta a eventos estressantes. Apesar do amplo conhecimento das respostas do estresse em mam?feros, os dados sobre a rela??o entre o estresse cr?nico imprevis?vel e seus efeitos na sinaliza??o purin?rgica s?o limitados. A sinaliza??o purin?rgica ? mediada por ATP e adenosina por meio da ativa??o dos receptores P2 e P1, respectivamente. O catabolismo de ATP extracelular at? adenosina ? promovido pelas ectonucleotidases, como as Ecto-nucleos?deo trifosfato difosfoidrolases (E-NTPDases) e Ecto-5 - nucleotidases (E-5?NT). A adenosina produzida pode ser desaminada pela adenosina desaminase (ADA), produzindo inosina. Assim, estas enzimas controlam os n?veis de nucleos?deos e nucleot?deos extracelulares, exercendo uma influ?ncia na sinaliza??o purin?rgica. Considerando que alguns modelos de estresse podem afetar os sistemas de sinaliza??o, o objetivo deste estudo foi verificar se o estresse cr?nico imprevis?vel altera as atividades ectonucleotid?sicas e adenosina desaminase em c?rebro de zebrafish. Al?m disso, analisamos o metabolismo do ATP, bem como a express?o de genes relacionados ? ADA, ada1, ada2.1, ada2.2, adaL, adaasi e os efeitos de agonistas e antagonistas de receptores de adenosina em zebrafish submetidos a um modelo de estresse cr?nico imprevis?vel. Nossos resultados demonstraram que n?o h? altera??es na hidr?lise de ATP (P = 0.1499), ADP (P = 0.3615) e AMP (P = 0.8987) em membranas cerebrais de zebrafish submetidos ao estresse cr?nico imprevis?vel. Em contraste, a atividade da ecto- ADA diminuiu significativamente (26,8%; 8.164 ? 0,78 NH3 min&#8722;1 mg&#8722;1 de prote?na; p < 0,05; n = 5) em membranas de c?rebro de animais expostos ao estresse cr?nico imprevis?vel quando comparado ao grupo controle (11.15 ? 2,16 NH3 min&#8722;1 mg&#8722;1 de prote?na; p < 0,05; n = 5). No entanto, a atividade da ADA citos?lica n?o foi alterada. A an?lise quantitativa por RT-qPCR n?o apresentou altera??es significativas ap?s a exposi??o do estresse cr?nico imprevis?vel na express?o g?nica nos genes ada1, ada2.1, ada2.2, adaL, adaasi. O metabolismo do ATP em prepara??es de membrana de c?rebro de zebrafish no grupo controle e estressado foi medido por cromatografia l?quida de alta efici?ncia (HPLC) e mostrou um aumento significativo de adenosina nos animais estressados. Considerando que os agonistas de receptores A1 t?m uma atividade ansiol?tica e os antagonistas dos receptores A2A podem exercer efeitos neuroprotetores, investigamos o efeito da administra??o de um agonista do receptor A1, N&#8310;-ciclopentiladenosina (CPA), e de um antagonista de receptores A2A, (ZM241385) em par?metros comportamentais de animais submetidos ao estresse cr?nico imprevis?vel, para verificar uma poss?vel rela??o entre o sistema adenosin?rgico e o estresse. Como resultado, observamos que esses compostos n?o foram capazes de reverter o efeito ansiog?nico causado pelo estresse cr?nico imprevis?vel. Uma vez que a adenosina tem efeitos neuromodulat?rios, as altera??es nos n?veis de adenosina podem desempenhar um papel nos mecanismos relacionados ao estresse, representando um mecanismo de compensa??o a fim de restaurar a homeostase.

Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2015-04-28T12:59:06Z No. of bitstreams: 1 467697.pdf: 3365118 bytes, checksum: f6826fc894e0d18084119ccb17fc33a1 (MD5) / Made available in DSpace on 2015-04-28T12:59:06Z (GMT). No. of bitstreams: 1 467697.pdf: 3365118 bytes, checksum: f6826fc894e0d18084119ccb17fc33a1 (MD5) Previous issue date: 2015-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The first line of defense of organism is made by phagocytic cells such as neutrophils. Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. Apoptosis is characterized by nuclear chromatin packaging and nuclear fragments and this death can be delayed by the presence of pathogens or chemicals components such as lipopolysaccharide (LPS). Neutrophils have other antimicrobial strategy, called neutrophil extracellular traps (NETs), which contributes to the elimination and control of the pathogen. NETosis is induced by infection, inflammation or trauma and represents an innate immune activation mechanism. The objective of this study was to evaluate the effect of Gallic acid (GA) in the control of apoptosis and release NETs. The results show that GA decreased the anti-apoptotic effect of LPS, blocked the induction of NETs and prevented the formation of free radicals induced by LPS. These findings demonstrate that the GA is a novel therapeutic agent for decreasing the exacerbated response of the body against an infectious agent. / A primeira linha de defesa do organismo ? feita por c?lulas fagoc?ticas como os neutr?filos. Apoptose e NETose dos neutr?filos s?o os dois maiores mecanismos de morte celular programada, que diferem em suas caracter?scas morfol?gicas e em seus efeitos sobre o sistema imune. A apoptose ? caracterizada pelo empacotamento da cromatina e dos fragmentos nucleares, por?m esta morte por ser atrasada pela presen?a de pat?genos ou pela presen?a de componentes qu?micos, como o lipopolissacar?deo (LPS). Os neutr?filos possuem outra estrat?gia antimicrobiana, chamada armadilhas extracelulares (NETs), que contribuem para elimina??o e controle do pat?geno. A NETose ? induzida por infec??o, inflama??o ou trauma e, representa um mecanismo de ativa??o da resposta imune inata. O objetivo deste estudo foi avaliar o efeito do ?cido g?lico (AG) no controle da apoptose e forma??o de NETs de neutr?filos. Os reultados mostram que o AG diminuiu o efeito anti-apopt?tico do LPS, bloqueou a libera??o de NETs e preveniu a forma??o de radicais livres induzidos por LPS. Estes resultados demonstram que o AG pode ser um novo agente terap?utico no controle da resposta exacerbada do corpo contra um agente infeccioso.