Made available in DSpace on 2014-06-11T19:25:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-11Bitstream added on 2014-06-13T18:53:24Z : No. of bitstreams: 1 castro_mgmt_me_jabo.pdf: 2415473 bytes, checksum: c2ac1404977205c00708d980ff1db437 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A correta orientação do Médico Veterinário, aos proprietários de cães, usados com finalidades reprodutivas, submetidas à quimioterapia com cisplatina, é importante na medida que este agente citostático age nas células em constante divisão, podendo ser citotóxico para as células germinativas testiculares. O objetivo desse trabalho foi avaliar a qualidade espermática através do espermograma, ultra-som e avaliação de ultraestruturas do testículo de cães que receberam cisplatina em diferentes momentos de análise espermática. A dose utilizada foi de 70 mg/m², dose terapêutica, em intervalos de 21 dias, totalizando 4 infusões. Os cães foram divididos em dois grupos de 4 animais cada, sendo que um dos grupos recebeu a quimioterapia e o protocolo de diurese para proteção renal, já o grupo controle não recebeu a cisplatina, estando sujeito apenas aos fatores ambientais e ao tratamento suporte. Os resultados obtidos demonstraram que a cisplatina influenciou na qualidade espermática de cães, pois elevou as patologias maiores e totais acima do aceitável para cães aptos a reprodução, além de alterações de volume testicular observados pelo exame ultra-sonográfico ao longo dos tratamentos e constatação da degeneração testicular em variados graus observados pela análise ultraestrutural. Portanto, infere-se que este citostático possa acarretar alterações morfofuncionais nos túbulos seminíferos / The Veterinary Doctor's correct orientation, to the proprietors of dogs, used with reproductive purposes, submitted to the chemotherapy with cisplatin, it is important in the measure that this citostatic agent acts in the cells in constant division, could be toxicity for the testicle germ cells . The objective of that work was to evaluate the spermatic quality through the spermogram, ultra-sound and evaluation of ultrastructures of the testicle of dogs that received cisplatin in different moments of spermatic analysis. The used dose was of 70 mg/m², therapeutic dose, in intervals of 21 days, totaling 4 infusions. The dogs were divided in two groups of 4 animals each, and one of the groups received the chemotherapy and the diuresis protocol for renal protection, the group control didn't already receive the cisplatin, being just subject to the environmental factors and the treatment supports. The obtained results demonstrated that the cisplatin influenced in the spermatic quality of dogs, because it elevated the larger and total pathologies above the acceptable for capable dogs the reproduction, besides alterations of volume testicular observed by the ultra-sound exam along the treatments and verification of the degeneration testicular in varied degrees observed by the analysis ultrastructural. Therefore, it is inferred that this citostatic agent can cart alterations morphofunctional in the seminiferous tubules

Made available in DSpace on 2014-10-09T12:48:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:47Z (GMT). No. of bitstreams: 1 09263.pdf: 2125133 bytes, checksum: 80e8ed6e5148248a4ac80749747ba6fa (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

O estresse parece favorecer a hiperalgesia e alodinia, podendo estar associados à alteração da função muscular mastigatória. Alterações morfofisiológicas em músculos da mastigação induzidos pela alteração oclusal associado ao estresse crônico ainda são escassas na literatura. Este estudo investigou os efeitos do estresse crônico repetido em músculo masseter superficial e profundo de ratos submetidos ou não à exodontia unilateral no ganho do peso dos animais, nas alterações morfológicas (HE, MET), histoquímicas (NADH, SDH e ROS), imunoistoquímicas (laminina e CD31), atividade de MMP-2, -9 e infiltração de neutrófilos (MPO). Vinte ratos (machos, 200g) foram alocados em quatro grupos (n=5): controle (GC), exodontia unilateral (GM), estresse crônico repetido (GE), exodontia associado ao estresse crônico repetido (GME). GE e GME foram submetidos a 10 dias de protocolo de estresse crônico repetido (2 horas diárias) a partir do 14º dia após a exodontia. Houve uma diminuição significativa no ganho de peso dos animais GE e GME. Não foram observadas alterações nos níveis de MMPs e na infiltração de neutrófilos no feixe superficial dos diferentes grupos. GE, GM e GME demostraram alterações morfofisiológicas, ultraestruturais e histoquímicas no feixe profundo, com características específicas e distintas de GC; GE apresentou as maiores alterações. Conclui-se que a exodontia e sua associação ao estresse foram responsáveis por discretas alterações morfofisiológicas no músculo masseter de ratos, contudo o estresse crônico repetido causou modificações morfofisiológicas e ultraestruturais significantes, sendo responsável também pela alteração no peso dos animais. / Stress seems to favor the hyperalgesia and allodynia, which may be related with altered masticatory muscle function. Morphological and physiological changes in the masticatory muscles induced by occlusal alteration associated with chronic stress are still scarce in the literature. This study investigated the effects of repeated chronic stress in superficial and deep masseter muscle of rats with or without the extraction unilateral weight gain of animals and morphological changes (HE MET), histochemical (NADH, SDH and ROS), immunohistochemical (laminin and CD31), MMP-2, -9 activities and neutrophil infiltration (MPO). Twenty rats (male, 200g) were allocated into four groups (n=5): control group (CG), unilateral exodontia (MG), repeated chronic stress (EG), extodontia and repeated chronic stress (MEG). EG and MEG were submitted to 10 days of repeated chronic stress protocol, 2 hours daily, from the 14th day after the extraction. There was a significant decrease in weight gain of animals EG and MEG. No changes were observed in the levels of MMPs and neutrophil infiltration among different groups. EG, MG and MEG have shown morphophisyological, ultrastructural and histochemical changes with specific characteristics and distinct GC GE presenting the higher changes. We conclude that the exodontia and its association to stress were responsible for discrete morphophysiological changes in the masseter muscle of rats, however repeated chronic stress caused significant morphophysiological and ultrastructural changes, being also responsible for change in weight of the animals.

Made available in DSpace on 2014-10-09T12:48:33Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:59:47Z (GMT). No. of bitstreams: 1 09263.pdf: 2125133 bytes, checksum: 80e8ed6e5148248a4ac80749747ba6fa (MD5) / Dissertacao (Mestrado Profissionalizante em Lasers em Odontologia) / IPEN/D-MPLO / Intituto de Pesquisas Energeticas e Nucleares, IPEN/CNEN-SP; Faculdade de Odontologia, Universidade de Sao Paulo

Orientador : Debora de Queiroz Tavares / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-03T22:28:57Z (GMT). No. of bitstreams: 1 Martini_MariaHelena_D.pdf: 15024202 bytes, checksum: 22ab2ff6f88e02fc090f712bfba73cea (MD5) Previous issue date: 2004 / Resumo: Nos estudos sobre as reservas do mesofilo cotiledonar do gênero Theobroma destacam-se os trabalhos sobre sementes de T. cacao, fonte única da matéria prima do chocolate. Estas pesquisas preferenciam as mudanças ocorridas na estrutura celular durante a fermentação, secagem, torração; etapas do processo de produção do chocolate. Mais recentes são os trabalhos com sementes de T. grandiflorum utilizadas na elaboração do cupulate, produto com características semelhantes ao chocolate. O presente trabalho analisa as células de reserva lípide-proteicas e idioblastos de polifenóis de T. cacao, T. grandiflorum, T. subincanum, T. bicolor e T. speciosum. Em T. obovatum e T. microcarpum o estudo apresentou apenas as células polifenólicas. A distribuição dos glóbulos lipídicos nas células são análogas nestas espécies, isto é, localização periférica e extrema susceptibilidade ao calor, coalescendo sob condições térmicas acima de 30°C. A proteína de reserva apresenta-se entremeada com os glóbulos lipídicos e alguns grãos de amido. As células polifenólicas, em T. bicolor e T. speciosum, localizam-se na região do feixe vascular e parênquima da radícula e nas outras espécies estudadas estão dispersas pelo mesofilo e próximas ao feixe vascular. A mucilagem é uma secreção celular constante em cinco espécies estudadas, não se acumulando dentro das células, porém com raras exceções ocorrem células com mucilagem na epiderme do mesofilo (T. subincanum). T. speciosum caracteriza-se por efetivamente apresentar células de mucilagem. Estas células são abundantes no mesofilo e cerca de 10% alcançam grandes dimensões sem rompimento do tecido. As células polifenólicas apresentam características histoquímicas semelhantes a mucilagem, porém sua estreita relação com os feixes vasculares direciona seu desenvolvimento para a síntese de polifenóis. O tecido do mesofilo cotiledonar é semelhante em todas as espécies aqui estudadas devido a predominância de reserva lípide-proteica. Células imaturas de sementes verdes demonstram capacidade para sintetizar todas as reservas; na maturidade celular demonstram predominância de reservas lípide-proteicas ou de mucilagem ou de polifenóis. A distribuição das reservas no mesofilo aproximam T. grandiflorum à T. subincanum. A maior quantidade de proteínas está em T. bicolor. Esta espécie apresenta menor quantidade de lipídeos e de células polifenólicas / Abstract: Many investigations on the cellular reserves within the cotyledon mesophyll of the Theobroma have been carried out on Theobroma cacao seeds, the source of raw for the production of chocolate. These studies demonstrated structural cellular changes due to fermentation, drying, and roasting processes during chocolate production. Recently the seeds of the T. grandiflorum have been analyzed due to their importance in the production of ¿cupulate¿, a new product similar to chocolate. In the present work, we analyze the lipid-protein reserve cells and polyphenolic idioblasts derived from T. cacao, T. grandiflorum, T. subincanum, T. bicolor, T. speciosum and T. obovatum. Only phenolic cells were studied in T.obovatum and T. microcarpum.The distribution of lipid bodies was similar in all the species studied; that is, they were located at the periphery of the cell wall and demonstrated extremely susceptibly to heat, coalescing at temperatures above 30°C. The reserve protein was interspersed with lipid bodies and some starch granules. The polyphenolic cells were dispersed throughout the mesophyll and around the vascular bundles in all the species studied. In T. bicolor and T. speciosum the polyphenolic cells were only observed around the vascular bundle and radicle parenchyma. Mucilage is a cellular secretion in the five species studied. Mucilage does not accumulate intracellularly; however, rarely we did observe mucilage in the cells of the mesophyll epidermis of T. subincanum. In T. speciosum, mucilage cells were abundant in the mesophyll and about 10% reached large dimensions without tissue disruption. The polyphenolic cells presented characteristic mucilage histochemistry, however their strict association with vascular bundles should direct their development towards polyphenol synthesis. Cotyledon mesophyll tissue is similar in all the species studied with respect to lipid-protein reserve. Immature cells demonstrated the capacity to synthesize all the reserves, but this capacity is not retained in the mature cell. The distribution of reserves in the mesophyll are most similar in T. grandiflorum and T. subincanum. T. bicolor showed a high protein content, lower lipid levels and low levels of polyphenolic cells / Doutorado / Doutor em Alimentos e Nutrição

Les parois des cellules végétales sont des structures formées de divers polymères polysaccharidiques et de nombreuses protéines. Ces structures possèdent un fort dynamisme assuré par l'action spécifique des protéines pariétales (CWP). Parmi ces CWP, se situent les peroxydases de classe III (CIII Prx) formant une famille multigénique de 73 membres chez la plante modèle Arabidospis thaliana. Les CIII Prxs assurent de nombreux rôles dans le développement et les interactions avec l'environnement mais seuls de rares études ont pu attribuer une fonction précise à un membre individuel de la famille. Ceci est probablement du à la faible spécificité de ces enzymes in vitro et à la possible redondance fonctionnelle obligeant à considérer des études in situ-in vivo et l'utilisation de mutants multiples. Dans ce contexte, le premier objectif de cette thèse était d'établir un atlas d'expression spatiotemporelle par hybridation in situ (HIS) utilisant le développement de la graine d'A. thaliana comme modèle. Ce travail s'est appuyé sur une étude de micro-transcriptomique récemment publiée, permettant d'établir des comparaisons avec nos résultats d'HIS. Ils ont montré une complémentarité entre les deux approches et permis (1) d'établir des seuils de valeurs de transcriptomiques compatibles avec la sensibilité de l'HIS et (2) de définir des candidats d'intérêt présentant des profils d'expression spatiotemporelle suggérant des fonctions précises. Le deuxième objectif de cette thèse a été de caractériser fonctionnellement l'un de ces candidats (AtPRX36). Nous avons pu démontrer le rôle de cette protéine dans le contrôle du relargage du mucilage polysaccharidique lors de l'imbibition de la graine. Nos résultats suggèrent que l'ancrage localisé de cette protéine est assuré par un microdomaine pectique d'homogalacturonane globalement méthylestérifié formé par l'action d'un inhibiteur de une pectine méthylestérase (PMEI6), et permet un rôle d'AtPRX36 dans le relâchement polarisé de la paroi au niveau de ce microdomaine délimitant la zone de rupture des graines lors de l'imbibition. / Plant cell walls are complex structures, mainly composed of a large number of polysaccharides and proteins. The cell wall (CW) is a highly dynamic compartment which is remodeled by specific cell wall proteins (CWP). Among these CWP, the plant specific class III peroxidases (CIII Prxs) are a multigenic family of 73 members in Arabidopsis thaliana. CIII Prxs are involved in plant development but also in the interaction of the plant with its environment. However, only a few studies describing the exact function of individual members of this multigenic family have been published. This can be due to the weak in vitro substrate specificity of these enzymes and their possible functional redundancy, forcing to characterize their function in situ-in vivo and the use of multiple mutants. In this context, the first goal of my thesis was to establish the fine cellular spatio-temporal expression atlas of CIII Prxs throughout the seed development of Arabidopsis thaliana with an in situ hybridization (ISH) approach. This expression work (ISH) was partially permitted thanks to a recent published micro-transcriptomic study which allowed to compare both expression results (ISH vs micro-transcriptomic). This comparison showed that both techniques are complementary and it allowed to; (1) set a threshold for the ISH detection limit based on micro-transcriptomic expression values, and (2) to define specific spatio-temporal expression pattern that helps to select CIII Prx candidates for functional study. The second objective was to characterize the function of one of these CIII Prxs candidates (AtPRX36). We were able to determine the role of AtPRX36 during mucilage extrusion of imbibed seeds.Our results suggest that AtPRX36 is anchored within a globally methylesterified pectins CW micro-domain, putatively formed by the action of a pectin methylesterase inhibitor (PMEI6). This CW micro-domain is needed for the CW loosening action of AtPRX36 to permit CW polarized rupture during seed imbibition.

No presente estudo realizamos uma análise ultraestrutural e imuhistoquímica da organização das fibrilas de colágeno no endométrio durante a gestação de camundongos silvestres e deficientes em decorim. Os resultados mostraram que as fibrilas de colágeno em ambos os genótipos sofrem grande variação de forma e tamanho. Observou-se variação significante, na percentagem de distribuição dos diâmetros das fibrilas de colágeno existentes na região decidualizada em ambos os genótipos, porém foi maior nos animais Dcn-/-. Estes animais também apresentam maior percentagem de fibrilas finas quando comparados aos animais Dcn+/+. Observamos ainda que biglicam é expresso no endométrio não decidualizado dos animais Dcn-/-, no 3º dia de gestação. A expressão de lumicam mostrou-se nítida no estroma decidualizado e não decidualizado nos animais Dcn-/- no 7º dia de gestação e foi ausente nos animais Dcn-/-. Estes resultados mostraram que a ausência do decorim promove distúrbios no processo de agregação lateral das fibrilas espessas de colágeno. / The present study is an ultrastructural investigation into the organization of collagen fibrils in the pregnant endometrium of wild-type and decorin-deficient mice. Our results showed that collagen fibrils from both genotypes present a great variability of shape and size in cross section. Significant variation in the diameter of collagen fibrils exists in the decidualized endometrium from both groups of animals. In the decidualized endometrium, the diameter of collagen fibrils increases in both genotypes were higher in Dcn-/- than in Dcn+/+ animals. In the Dcn-/- animals the percentage of thin fibrils with diameter is also higher, when compared with Dcn+/+ animals. We also showed that Bgn is expressed in the non decidualized endometrium in the Dcn-/- animals, on day 3 of pregnancy. The expression of lumican showed a very sharp labeling in the decidualized stroma from day 7, and in the non decidualized estroma from Dcn-/- animals. These results suggest that the deficience of decorin may play a role on collagen fibrillogenesis in different stages of pregnancy.

Fine structural analyses of host tissue (alfalfa, Medicago sativa L.) response to infection by the stem nematode (Ditylenchus dipsaci Kühn) were conducted. Hypocotyl regions were taken on 1,3 and 7 days after inoculation. Electron micrographs of infected tissue indicated the types of damage were the same between Lahontan (tolerant line) and Ranger (susceptible line). Only the infection rate (in percent) and degree of damage were different between lines and among the different temperatures (15, 20 and 25 C). The higher the temperature, the more injury resulted. After 3 to 7 days of infection, the symptoms observed were swelling and broken endoplasmic reticulum (ER), distended and broken chloroplasts, loss of nuclear material and bulging and rupturing of nuclear envelopes. Heavily infected cell walls showed more osmiophilic substances on one side. Infected cytoplasm contained more ER (both rough and smoothER), ribosomes, vesicles and Golgi apparatus, suggesting increased metabolic activities. Lobing nuclei were observed in all treatments. Lipid content varied with temperature in one-day-old seedlings. At 15 and 25 C, electron dense substances were commonly found along the tonplast, intercellular spaces and on the cell wall. Also some enlarged ER were noted in the non-infected controls at these temperatures. From the fine structural studies of host tissue it is not possible at this time to determine the nature of resistance of alfalfa lines to nematode infection. More studies at both the biochemical and electron microscopical levels are needed. Further, studies on the activities of the nematodes at the various temperatures during the infection periods would be primarily important.

Vitamin E and selenium play key roles in preventing in vitro lipid peroxidation and free radical damage to retinal tissues. In this research, we studied the effects of hyperbaric oxygen on retinal structure in rats fed diets deficient in vitamin E and/or selenium. We also correlated any alterations in retinal structure with previously measured alterations in electroretinograms (ERGs). Age-matched rats were fed a basal diet deficient in both vitamin E and selenium (B diet), a basal diet supplemented with vitamin E alone (B+E diet), or selenium alone (B+Se diet), or with both micronutrients (B+E+Se). Half the rats in each group were treated (+ HBO) with hyperbaric oxygen (100% O2 at 3 ATA for 1·5 per hr day, 5 days per week) and half were not (-HBO). We previously found that the rats fed the B diet for 6 weeks and treated with HBO for 4 weeks (B+HBO group) had diminished a-wave ERG amplitudes. At this time point all rats in the B group and half of the rats in the B+E+Se group were killed for the structural studies reported here. Surprisingly, we found no evidence of photoreceptor cell necrosis [i.e. a decreased thickness of the outer nuclear layer (ONL)] in retinas from rats in the B+HBO group despite the diminished amplitude of the a-wave which arises from this retinal layer. Quantitative structural analyses of retinas from rats in the B+HBO, B-HBO, B+E+Se-HBO and B+E+Se+HBO groups also failed to reveal any significant differences in the cell height of the retinal pigmented epithelium (nasal, central or temporal regions) or the number of mitochondria, phagosomas or inclusion bodies in the central retinal pigment epithelium (RPE). The inner nuclear layer (INL) thickness was, however, consistently decreased in all retinal regions for the rats in the B+HBO group. Our previous work also showed that only rats fed the B+Se diet for 17 weeks and treated with HBO for 15 weeks (B+Se+HBO group) showed diminished a-wave and b-wave ERG amplitudes. At this time point rats in the B+E+Se, B+E, and B+Se groups were killed for structural studies reported here. Only rats in the B+Se+HBO group showed a significantly decreased (about 20%) thickness of the central ONL. This evidence of photoreceptor cell necrosis correlated very well with our previous observation of diminished a- and b-wave amplitudes only in the B+Se+HBO group (at week 17). Ultrastructural studies after 17 weeks of feeding the experimental diets revealed two different types of inclusion bodies in the central RPE. On the basis of morphological appearance we have termed these inclusion bodies 'electron-dense' and 'granulated'. The central RPE of rats in the B+Se+HBO and B+Se-HBO groups showed a larger number (P < 0·001) of 'granulated' inclusion bodies and a smaller number (P < 0·001) of 'electron-dense' inclusion bodies than rats in any other diet/treatment group at this time point. In marked contrast, there were no observable 'granulated' inclusion bodies and no significant differences in the number of electron-dense inclusion bodies found in the central RPE from rats in any diet/treatment group after 6 weeks of feeding the experimental diets. Our results are discussed with respect to the potential effects of lipid peroxidation on retinal morphology and on electroretinograms.

A homocisteína é um aminoácido sulfurado derivado do metabolismo da metionina. Quando os níveis plasmáticos de homocisteína ultrapassam 10-15 μM, tem-se uma condição conhecida como hiperhomocisteinemia, a qual pode ser classificada em leve (>10 μM), moderada (>30 μM) ou severa (>100 μM). A hiperhomocisteinemia leve não tem origem genética, sendo considerada um fator de risco para o desenvolvimento de doenças neurodegenerativas e vasculares, incluindo isquemia cerebral e cardíaca. Nosso grupo de pesquisa desenvolveu um modelo químico induzido de hiperhomocisteinemia leve crônica em ratos adultos jovens e, usando esse modelo foi mostrado que existe associação entre essa condição e alterações em parâmetros de inflamação e estresse oxidativo/nitrativo em tecido cerebral. O objetivo do presente estudo foi avaliar se o ácido acetilsalicílico tem papel neuroprotetor no efeito da homocisteína sobre os níveis de interleucinas IL-1β e IL-6, atividade e imunoconteúdo da acetilcolinesterase, biodisponibilidade de óxido nítrico, atividade e imunoconteúdo das enzimas antioxidantes superóxido dismutase e catalase, conteúdo de sulfidrilas e índice de dano ao DNA. Também realizamos análise morfológica por microscopia eletrônica de transmissão em córtex cerebral de ratos submetidos ao modelo. Ratos Wistar receberam homocisteína (0,03 μmol/g de peso corporal) por injeções subcutâneas duas vezes ao dia e ácido acetilsalicílico (25 mg/Kg de peso corporal) por injeções intraperitoneais uma vez ao dia, do dia 30 ao 60º dia pós-parto Ratos controles receberam o mesmo volume da solução veículo. Doze horas após a última injeção, alguns animais foram decapitados para posteriores análises bioquímicas, e outros animais foram perfundidos para posterior análise morfológica. Os resultados mostraram que os ratos submetidos à hiperhomocisteinemia leve apresentaram aumento significativo dos níveis de IL-1β, IL-6 e da atividade da acetilcolinesterase, bem como níveis reduzidos de nitritos. A homocisteína também diminuiu as atividades da superóxido dismutase e catalase, bem como o imunoconteúdo da catalase. Danos às proteínas e DNA, assim como alterações ultraestruturais também foram observadas no córtex cerebral dos animais hiperhomocisteinêmicos. O ácido acetilsalicílico preveniu totalmente o efeito da homocisteína sobre a atividade da acetilcolinesterase, atividade e imunoconteúdo da catalase, e alterações ultraestruturais. As alterações nos níveis de IL-1β, atividade de superóxido dismutase, conteúdo de sulfidrilas e dano ao DNA foram parcialmente prevenidas pelo ácido acetilsalicílico. Nossos achados mostraram que o modelo induzido quimicamente de hiperhomocisteinemia leve alterou alguns parâmetros inflamatórios, oxidativos/nitrativos e morfológicos. Nossos resultados também sugerem que o ácido acetilsalicílico desempenha um papel neuroprotetor nas condições apresentadas, pois preveniu a maior parte dessas alterações. Porém, a administração crônica do ácido acetilsalícico também apresentou efeito per se significativo de dano ao DNA, o qual deve ser melhor elucidado em estudos posteriores. / Homocysteine is a sulfur amino acid derived from methionine metabolism. When plasma homocysteine levels exceed 10-15 μM, there is a condition known as hyperhomocysteinemia, which can be classified as mild (>10 μM), moderate (>30 μM), or severe (>100 μM). Mild hyperhomocysteinemia does not have genetic origin and it is considered a risk factor for the development of neurodegenerative and vascular diseases, including cerebral and cardiac ischemia. Our research group has developed an induced chemical model of chronic mild hyperhomocysteinemia in young adult rats and using this model, it has been shown an association between this condition and changes in parameters of inflammation and oxidative/nitrative stress in brain tissue. The objective of the present study was to evaluate if acetylsalicylic acid has a neuroprotective role in the effect of homocysteine on IL-1β and IL-6 interleukin levels, acetylcholinesterase activity and immunocontent, nitric oxide bioavailability, activity and immunocontent of antioxidant enzymes superoxide dismutase and catalase, sulfhydryl content and DNA damage index. We also performed morphological analysis by transmission electron microscopy in the cerebral cortex of rats submitted to the model. Wistar male rats received homocysteine (0.03 μmol/g of body weight) by subcutaneous injections twice a day and acetylsalicylic acid (25 mg/Kg of body weight) by intraperitoneal injections once a day from the 30th to the 60th postpartum day Control rats received the same volume of vehicle solution. Twelve hours after the last injection, some animals were decapitated for subsequent biochemical analyzes, and other animals were perfused for subsequent morphological analysis. The results showed that rats submitted to mild hyperhomocysteinemia significantly increased levels of IL-1β, IL-6, acetylcholinesterase activity and reduced nitrite levels. Homocysteine also decreased the activities of superoxide dismutase and catalase, as well as catalase's immunocontent. Damage to proteins and DNA as well as ultrastructural changes were also observed in the cerebral cortex of hyperhomocysteinemic animals. Acetylsalicylic acid totally prevented the effect of homocysteine on acetylcholinesterase activity, catalase activity and immunocontent, and ultrastructural changes. Alterations in IL-1β levels, superoxide dismutase activity, sulfhydryl content and DNA damage were partially prevented by acetylsalicylic acid. Our findings showed that the chemically induced model of mild hyperhomocysteinemia altered some inflammatory, oxidative/nitrative and morphological parameters. Our results also suggest that acetylsalicylic acid plays a neuroprotective role in the conditions presented, as it prevented most of these changes. However, chronic administration of acetylsalicylic acid also had a significant effect of DNA damage, which should be better elucidated in later studies.