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- ItemRestritoCaracterização do remodelamento cardíaco de camundongos mdx submetidos a treinamento aeróbico(Universidade Federal de São Paulo, 2022-09-05) Cabanelas, Luciana Alécio [UNIFESP]; De Oliveira, Flavia [UNIFESP]; http://lattes.cnpq.br/3387760393535776; http://lattes.cnpq.br/9166265182368920; Universidade Federal de São Paulo (UNIFESP)A distrofia muscular de Duchenne (DMD) é uma doença hereditária progressiva e com envolvimento cardíaco. Este estudo teve como objetivo avaliar os mecanismos envolvidos no remodelamento cardíaco do ventrículo esquerdo de modelos experimentais para a DMD (camundongos mdx) submetidos ao exercício físico aeróbico, a fim de acelerar a progressão da doença. Foram utilizados camundongos C57BL/10 e C57BL/10-DMDMdx, machos, com 6 meses de idade. O protocolo de exercício físico teve duração de oito semanas para os grupos treinados (Mdx-T), enquanto os animais dos grupos controle (C) e mdx sedentário (Mdx-S) não passaram por intervenção. Após a eutanásia, os corações foram removidos para serem submetidos às análises: morfométrica (análise da densidade dos núcleos e espessura dos cardiomiócitos e análise do tecido conjuntivo); imunoistoquímica para análise in situ das proteínas: MMP-2, MMP-9, COX-2 e 8-OHdG. Foi empregado o teste de t de Student para a comparação entre os grupos em relação às variáveis da espessura dos cardiomiócitos, área do perfil dos cardiomiócitos e estereologia do colágeno. Para a imunomarcação do 8-OHdG e COX-2 utilizou-se ANOVA seguido de comparações múltiplas de Tukey. Como resultados, as fotomicrografias indicaram que os grupos Mdx-S e Mdx-T apresentaram perda difusa dos cardiomiócitos, aumento do espaço de matrix extracelular e das áreas de infiltrado inflamatório e de tecido conjuntivo, sendo essas alterações mais evidentes no Mdx-T. A análise morfométrica mostrou que a espessura dos cardiomiócitos dos animais Mdx-T foi menor que a do Mdx-S. Na análise qualitativa da MMP-2 e 9, foi possível observar imunoreatividade em áreas de acúmulo de tecido conjuntivo nos animais mdx, mais evidentes nos grupo Mdx-T. A imunoexpressão da COX-2 foi maior nos animais do grupo Mdx-T do que no Mdx-S e grupo C. Já a presença do 8-OHdG foi maior no grupo Mdx-T e Mdx-S quando comparados ao grupo C. O protocolo de exercícios utilizado foi capaz de exacerbar o quadro de degeneração e atrofia dos cardiomiócitos. Ainda nos animais Mdx-T houve maior degradação do colágeno relacionado às MMPs e exacerbação do quadro inflamatório e estresse oxidativo relacionado a danos ao DNA, evidenciados pela maior presença da COX-2 e do 8-OHdG, respectivamente.
- ItemAcesso aberto (Open Access)Collagen and reticular fibers in left ventricular muscle in diabetic rats: Physical exercise prevents its changes?(Churchill Livingstone, 2011-02-01) Castellar, Alexandre; Remedio, Rafael Neodini; Barbosa, Rodrigo Avelaira; Gomes, Ricardo José [UNIFESP]; Caetano, Flavio Henrique; São Paulo State Univ; Universidade Federal de São Paulo (UNIFESP)Diabetic cardiomyopathy contributes to the high incidence of mortality in both types of diabetes. We aimed to investigate the histochemical aspects of collagen and reticular fibers in the cardiac muscle and evaluate the influence of physical exercise on these aspects. Wistar rats were divided in 4 groups: sedentary control (SC), trained control (TC), sedentary diabetic (SD) and trained diabetic (TD). Diabetes was induced with alloxan (35 mg/kg). Training program consisted of swimming 1 h/day with a load of 4.8% of body weight for TD and 5.2% for TC. during 8 weeks. At the end of the experiment, samples of the left ventricle were collected, fixed in Bouin and processed on historesin. Sections were stained with periodic acid of Schiff, picrosirius-hematoxylin and ammoniacal silver. the PAS technique shows that individuals of group SD presented more intense reaction that the other groups. Picrosirius-hematoxylin technique showed a possible deposition of collagen fibers in SD. the TD group presented a reaction a lot similar to the controls' for both techniques', showing a possible prevention of this deposition. These results indicate that physical exercises might have an important role on the prevention of some negative alterations caused by experimental diabetes. (C) 2010 Elsevier B.V. All rights reserved.
- ItemSomente MetadadadosEficácia Da Vacina Com O Gene Da Asp-2 Contra A Doença De Chagas Em Camundongos: Aspectos Histopatológicos, Inflamatórios E Toxicogenômicos(Universidade Federal de São Paulo (UNIFESP), 2018-04-25) Ribeiro, Flavia Andressa Pidone [UNIFESP]; Ribeiro, Daniel Araki [UNIFESP]The Aim Of This Study Was To Evaluate The Therapeutic Potential Of The Replication Defective Human Adenovirus Type 5 Vaccine, Which Contained The Sequence Of The Amastigote Surface Protein-Asp-2 Gene In An Experimental Model Of Chagas' Disease. For This, A Total Of 16 Female Mice A / Sn Was Distributed In 4 Groups With 4 Animals Each: Group 1 - Control (Ctrl): The Animals Were Not Submitted To Therapeutic Treatment Or Infection; Group 2 - Infected (Tc): The Animals Were Infected With T. Cruzi; 3- Immunized Group (Adasp-2): Animals Were Immunized With Adasp-2 At Day Zero Intramuscularly; Group 4 - Immunized And Infected (Adasp-2+Tc): Animals Were Immunized With Adasp-2 At Day Zero And Infected With T. Cruzi On The Same Day. On The 17th Day, All Animals Were Euthanized And Their Hearts Were Extracted For Histopathological Analysis And Gene And Protein Expression. The Group Of Animals That Were Vaccinated And Infected (Adasp-2+Tc) Presented Histopathological Changes In Myocardium And Liver, But Of Lesser Severit
- ItemAcesso aberto (Open Access)Morfologia dos cardiomiócitos e quantificação do colágeno no miocárdio de ratas tratadas com isoflavonas ou estrogênios(Federação Brasileira das Sociedades de Ginecologia e Obstetrícia, 2012-10-01) Cabanelas, Luciana Alécio [UNIFESP]; Carbonel, Adriana Aparecida Ferraz [UNIFESP]; Santos, Miriam Aparecida dos [UNIFESP]; Simões, Ricardo Santos; Liberatori-Filho, Aroldo Walter [UNIFESP]; Baracat, Edmund Chada [UNIFESP]; Soares Júnior, José Maria [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Universidade de São Paulo (USP)PURPOSES: To evaluate the histomorphometry of cardiomyocytes and collagen present in the myocardium of rats treated with a concentrated extract of soy or 17β-estradiol (E2). METHODS: Twenty-eight rats were divided into four groups: GCtrl - estrus phase; GOvx - ovariectomized (Ovx) and receiving vehicle; GIso - Ovx and treated with soy extract (150 mg/kg per day); GE2 - Ovx and treated with E2 (10 µg/kg per day). The drugs and vehicle (0.2 mL propylene glycol) were administered for 30 consecutive days after ovariectomy. On the last day the animals were anesthetized, the hearts removed, submerged in 10% formaldehyde and fragments of the ventricles underwent histological procedures, and the sections were stained with hematoxylin and eosin or picrosirius-red. Histomorphometric analysis (number and volume of nuclei and quantification of collagen) was performed under a light microscope with AxioVision Rel. 4.2 software, and collagen fibers were quantified using IMAGELAB-2000 software. Data were submitted to ANOVA followed by the Tukey test (p<0.05). RESULTS: We observed a higher number of cardiomyocyte nuclei in animals of the Ovx and Iso groups than in GE2 and GCtrl animals (GOvx=121.7±20.2=GIso=92.8±15.4>GE2=70.5±14,8=GCtrl=66.3±9.6; p <0.05), while the nuclear volume was greater in the Ctrl and E2 groups (GE2=35.7±4.8 GCtrl=29.9±3.6=>GIso=26.5±4.5=GOvx=22.4±2.9; p <0.05). Collagen concentration was higher in the Ovx group (GOvx=5.4±0.1>GCtrl=4.0±0.1=GIso=4.4±0.08=GE2=4.3±0.5; p <0.05). CONCLUSIONS: Estrogen may prevent the reduction of the nuclear volume of cardiomyocytes and collagen deposition between heart muscle fibers, while the administration of isoflavones only prevents the deposition of collagen, which can preserve the mechanical properties of cardiac fibers.
- ItemSomente MetadadadosThermotolerance does not reduce the size or remodeling of radiofrequency lesions in the rat myocardium(Springer, 2013-01-01) Santos, Luis Felipe dos [UNIFESP]; Antonio, Ednei Luiz [UNIFESP]; Serra, Andrey Jorge; Venturini, Gabriela; Montemor, Jairo [UNIFESP]; Okada, Mieko [UNIFESP]; Araujo, Sergio [UNIFESP]; Tucci, Paulo [UNIFESP]; Paola, Angelo de [UNIFESP]; Fenelon, Guilherme [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Nove Julho UnivLate lesion extension may be involved in the genesis of delayed radiofrequency (RF) effects. Because RF lesion is thermally mediated, we hypothesized that induction of heat shock response (thermotolerance) would modulate lesion healing. We evaluated the effects of thermotolerance on the dimensions and remodeling of RF lesions in a rat model of heart failure.Wistar rats (weight 300 g) subjected to heat stress (n = 22, internal temperature of 42 A degrees C for 10 min) were compared to controls (n = 22, internal temperature of 37 A degrees C for 10 min). After 48 h (peak of HSP70 myocardial concentration), a modified unipolar RF lesion (customized catheter, tip 4.5 mm in diameter; 12 W; 10 s) was created on the left ventricular free wall. Animals were sacrificed 2 h (n = 10 per group) and 4 weeks (n = 12 per group) after ablation for lesion analysis. An echocardiogram was obtained at 4 weeks.There was no difference between groups regarding the size of acute (controls 27 +/- 2 vs. treated 27 +/- 3 mm(2)) and chronic lesions (controls 17 +/- 1 vs. treated 19 +/- 1 mm(2)). Histology of lesions did not differ between groups. the echocardiogram revealed dilation of the cavities and moderate systolic dysfunction without difference between groups. Acute lesion dimensions were similar between control and treated animals over time (ablation undertaken 3, 12, 24, 48, and 72 h after hyperthermia) and also using a conventional ablation catheter (50 A degrees C; 15 W; 10 s).Thermotolerance does not reduce the size or remodeling of RF lesions in the rat myocardium.