Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A fibrose hepática é o resultado de uma resposta cicatrizante frente a repetidas lesões no fígado, e é caracterizada pelo acúmulo excessivo de proteínas da matriz extracelular (MEC) no parênquima hepático, incluindo colágeno, fibronectina, elastina, laminina e proteoglicanos, com a participação de diferentes populações celulares do fígado. As principais células responsáveis pela síntese de proteínas da MEC na fibrose hepática são as células estreladas hepáticas ativadas e os miofibroblastos, que surgem após estímulo inflamatório e são caracterizadas pela expressão de alfa-actina de músculo liso (α-SMA). Sabe-se que durante a progressão da fibrose hepática, ocorre a morte de hepatócitos e sua substituição por células fibrogênicas α-SMA+. A apoptose dessas células fibrogênicas é de grande relevância para a regressão da fibrose e regeneração hepática. Nos últimos anos, a terapia com células tronco de medula óssea tem sido utilizada para estimular a regeneração hepática em diferentes modelos experimentais e protocolos clínicos. A fração mononuclear da medula óssea adulta possui duas populações de células-tronco importantes no tratamento de diversas doenças hepáticas: células-tronco hematopoiéticas e células-tronco mesenquimais. O objetivo deste estudo foi analisar a expressão de α-SMA e o processo de apoptose de células hepáticas durante a fibrose hepática induzida por ligadura do ducto biliar (LDB) e após o transplante de células mononucleares de medula óssea (CMMO). Os fígados foram coletados de ratos dos seguintes grupos: normal, 14 dias de LDB, 21 dias de LDB e animais que receberam CMMO após 14 dias de LDB, e foram analisados após 7 dias (totalizando 21 dias de LDB). Para quantificar a expressão de α-SMA por células fibrogênicas nos grupos experimentais, foi realizada imunoperoxidase para α-SMA, seguida de morfometria no programa Image Pro Plus. Para analisar a apoptose nas células hepáticas, foi realizada imunoperoxidase e Western Blotting (WB) para caspase-3 (proteína apoptótica) e imunofluorescência com dupla-marcação para caspase-3 e α-SMA, seguida de observação em microscópio confocal. Os resultados da quantificação de α-SMA por morfometria mostraram que a expressão de α-SMA aumentou significativamente 14 e 21 dias após a LDB. Entretanto, essa expressão diminuiu significativamente no grupo tratado com CMMO, que apresentou parênquima hepático mais preservado em relação ao grupo com 21 dias de LDB. Os resultados de imunoperoxidase, WB e microscopia confocal para expressão de caspase-3 demonstraram que essa proteína diminuiu nos animais fibróticos com 14 e 21 dias de LDB com relação ao grupo normal, e estava significativamente elevada no grupo tratado com CMMO. A análise por microscopia confocal demonstrou que algumas células coexpressaram α-SMA e caspase-3 nos animais tratados com CMMO, sugerindo a morte de células fibrogênicas e remodelamento do parênquima hepático. / Hepatic fibrosis is the result of a scarring response due to continued injury to the liver, and is featured by excessive accumulation of extracellular matrix (MEC) proteins in hepatic parenchyma. These proteins include collagen, fibronectin, elastin, laminin and proteoglicans, along with the participation of different cell populations within the liver. The main cells responsible for the synthesis of MEC proteins are activated hepatic stellate cells and myofibroblasts, which appear after inflammatory stimuli and are characterized by the expression of alpha-smooth muscle actin (α-SMA). It is known that hepatic fibrosis progression is accompanied by hepatocyte death and its substitution by α-SMA+ fibrogenic cells. Therefore, apoptosis of these fibrogenic cells is of main relevance to fibrosis regression and hepatic regeneration. In the later years, bone marrow stem cell therapy has been used to stimulate hepatic regeneration in different experimental models and clinical protocols. The adult bone marrow mononuclear fraction contains two stem cell populations particularly important in the treatment of diverse hepatic diseases: hematopoietic stem cells and mesenchymal stem cells. The aim of this study was to analyze α-SMA expression and the apoptotic process in hepatic cells during hepatic fibrosis induced by bile duct ligation (BDL) and after bone marrow mononuclear cell (BMMC) transplantation. Livers were collect from rats of the following groups: normal, 14 days of BDL, 21 days of BDL and rats that received BMMC 14 days after BDL and were analyzed after 7 days (total of 21 days of BDL). To quantify α-SMA expression by fibrogenic cells in the experimental groups, immunoperoxidase to α-SMA followed by morphometry in the Image Pro Plus software was performed. To analyze apoptosis in hepatic cells, immunoperoxidase and western blotting (WB) against caspase-3 (apoptotic protein) were used, along with double immunofluorescence against caspase-3 and α-SMA to confocal microscopy analysis. Results of α-SMA quantification by morphometry showed that α-SMA expression increased significantly 14 and 21 days after BDL. However, this expression was significantly decreased in the BMMC treated group, which presented a more preserved hepatic parenchyma in relation to the group with 21 days of BDL. Immunoperoxidase, WB and confocal microscopy results showed that caspase-3 is decreased in fibrotic livers with 14 and 21 days of BDL in comparison to normal group, and was significantly augmented in the BMMC treated group. Confocal microscopy analysis showed that were cells coexpressing α-SMA and caspase-3 in rats treated with BMMC, suggesting fibrogenic cells death and hepatic remodeling.

A insuficiência renal crônica (IRC) é caracterizada por alterações glomerulares secundárias aos mecanismos adaptativos ocasionados por perda de néfrons funcionantes. Alterações na hemodinâmica glomerular, proliferação celular, influxo de células inflamatórias, desequilíbrio na síntese de proteínas da matriz extracelular glomerular (MECG) e perda da seletividade de carga e/ou tamanho da membrana basal glomerular têm sido apontados como mecanismos envolvidos na expansão mesangial e conseqüente glomeruloesclerose. A participação dos hormônios sexuais na função renal e na evolução da insuficiência renal crônica tem sido sugerida. Os glicosaminoglicanos, especialmente o heparan sulfato (HS), têm sido associados à seletividade glomerular de macromoléculas. O remodelamento podocitário precoce e a proteinuria (PTN) se relacionam com a progressão da IRC. Neste contexto, o acúmulo de MECG, proliferação de miofibroblastos e PTN têm sido apontados como mediadores precoces que precedem as lesões glomerulares e túbulo-intersticiais. Neste estudo, avaliamos as alterações renais precoces (30 dias de IRC) gênero-dependentes em ratos (M) e ratas (F) Wistar submetidos à redução de 5/6 da massa renal (IRC) e à castração (c). Os animais foram divididos em 10 grupos: Controles (C) (CM, CF, CMc, CFc) e sham (CM sham, CF sham); e aqueles submetidos à nefrectomia 5/6: IRCM, IRCF, IRCMc, IRCFc. Os animais foram castrados com 5 semanas e submetidos à nefrectomia 5/6 com 7 semanas de idade. Resultados significativos mostraram que os machos com IRC apresentaram maior PTN, acompanhada de maior comprometimento mesangial, imunomarcação positiva para &#945;-actina e maior concentração de heparan sulfato (HS) comparados com as fêmeas IRC (p<0,05). Estas alterações foram reduzidas nos machos castrados. A análise da morfologia podocitária mostrou raras regiões onde ocorreram alterações podocitárias nos grupos IRC. O conjunto de dados sugere que o hormônio masculino pode participar na manutenção do equilíbrio mesangial e que a PTN participa do processo de expansão mesangial. Adicionalmente, a maior concentração de HS nos machos com IRC sugere que durante o processo de remodelação da MEG, tenha ocorrido geração de HS de novo, funcionalmente defeituoso, comprometendo a barreira de filtração glomerular, corroborando com a perda de seletividade da mesma e, contribuindo para maior PTN neste grupo. As fêmeas com IRC apresentaram alterações mais discretas quando comparadas aos machos; apresentaram decréscimo de HS renal associado a PTN e a castração não alterou este perfil. Em resumo, a PTN ocorre precocemente na IRC, contribuindo para o desequilíbrio da MECG. Os mecanismos envolvidos nestes processos parecem sofrer influência dos hormônios sexuais; e os hormônios masculinos parecem agravar estas alterações, contribuindo possivelmente para um pior prognóstico da doença renal nos machos. / Chronic renal failure (CRF) is characterized by adaptive mechanisms secondary to the loss of functioning nephrons. Glomerular hemodynamics alterations, cellular proliferation, inflammatory cells influx, imbalance between synthesis and degradation of the glomerular extracellular matrix (GECM) and loss of charge and/or size selectivity of the glomerular basal membrane are pointed as mechanisms leading to mesangial expansion and glomerulosclerosis. Additionally, participation of gender related hormones on renal function and progression of CRF have been suggested. We evaluated the effect of castration in renal alterations in males (M) and females (F) Wistar rats, after 30 days of 5/6 reduction of renal mass (CRF). The animals were castrated (c) at 5 weeks old and 7 weeks old 5/6 and sham nephrectomy were done. Groups: Control (C) CM, CM sham, CMc, CF, CF sham, CFc, CRFM, CRFMc, CRFF, CRFFc. CRFM group showed higher proteinuria followed by increased mesangial expansion and &#945;-actin immunostaining. Concomitant higher concentration of heparan sulfate (HS) was also observed when compared to CRFF (p<0.05). These alterations were reduced in CRFMc group. Podocyte morphology analysis through electronic microscopy showed few disorders of foot processes in CRF groups Overall, CRFF group showed fewer alterations compared to males, and a reduction of HS was observed in association with PTN. Castration did not change this profile in female rats. Data suggest that male hormones may participate in the maintenance of the mesangial equilibrium and that PTN collaborated with the mesangial expansion process. Additionally, the higher concentration of HS in CRFM suggest that the remodeling process of the GECM, included a synthesis of de novo HS, that presented a functioning defect, compromising the glomerular filtration barrier and, ultimately corroborated with the loss of its selectivity and consequently with a higher PTN. This set of results leads us to conclude that PTN appears early in the course of CRF, may contribute to renal GECM imbalance and, the mechanisms involved in these processes seem to be influenced by gender-related hormones. In addition, male hormones seem to aggravate renal alterations contributing to a poor prognosis of CRF progression in male rats.

1 Abstract Introduction Autologous transplants of the cartilage tissue from the pinna is commonly used in reconstructive surgery of the nasal skeleton. The present study used animal models to elucidate responses of the auricular cartilage to its damage or transplantation to ectopic sites. Histomorphological analysis of changes observed in auricular cartilage including immunohistochemical study of different isoforms of actin and S-100 proteins was performed. Human articular cartilage prepared by in vitro cultivation using artificial scaffolds was also studied after its transplantation. Aims of the study The aim was to study histological changes and expression of chondrocytic markers (α- SMA and S-100 proteins) in intact, artificially traumatised, or in a human auricular cartilage cultivated in culture medium. An attempt to grow human auricular cartilage chondrocytes implanted in vitro into various types of three dimensional scaffolds aimed at testing chondrocyte survival and phenotype both in the culture and after transplantation to immunodeficient mice. A human auricular cartilage transplanted into the nasal skeleton of patients during a reconstruction surgery should be submitted to a histomorphological examination. Research assumed also comparison of the auricular cartilage responses to a damage,...

1 Abstract Introduction Autologous transplants of the cartilage tissue from the pinna is commonly used in reconstructive surgery of the nasal skeleton. The present study used animal models to elucidate responses of the auricular cartilage to its damage or transplantation to ectopic sites. Histomorphological analysis of changes observed in auricular cartilage including immunohistochemical study of different isoforms of actin and S-100 proteins was performed. Human articular cartilage prepared by in vitro cultivation using artificial scaffolds was also studied after its transplantation. Aims of the study The aim was to study histological changes and expression of chondrocytic markers (α- SMA and S-100 proteins) in intact, artificially traumatised, or in a human auricular cartilage cultivated in culture medium. An attempt to grow human auricular cartilage chondrocytes implanted in vitro into various types of three dimensional scaffolds aimed at testing chondrocyte survival and phenotype both in the culture and after transplantation to immunodeficient mice. A human auricular cartilage transplanted into the nasal skeleton of patients during a reconstruction surgery should be submitted to a histomorphological examination. Research assumed also comparison of the auricular cartilage responses to a damage,...

Durante o processo de reparação tecidual, o fator de transformação de crescimento <font face=\"symbol\">b1 (TGF-<font face=\"symbol\">b1) apresenta um importante papel na regulação da expressão da <font face=\"symbol\">a-actina de músculo liso (<font face=\"symbol\">a-AML) e portanto, na diferenciação miofibroblástica. Como os fibroblastos pulpares apresentam características peculiares, com a expressão de proteínas específicas que os diferem de fibroblastos de outros tecidos conjuntivos, o presente estudo avaliou in vitro se o TGF-<font face=\"symbol\">b1 aumenta a expressão de <font face=\"symbol\">a-AML em fibroblastos pulpares humanos comparando-os com fibroblastos de gengiva. Para tal, diferentes doses de TGF-<font face=\"symbol\">b1 (5 à 10 ng/ml) foram adicionadas às culturas de células, sendo a expressão da <font face=\"symbol\">a-AML analisada por imunofluorescência e western-blotting. Ambos os tipos celulares imunoexpressaram <font face=\"symbol\">a-AML mesmo sem o tratamento com o TGF-<font face=\"symbol\">b1, estando aumentada consideravelmente, quando o TGF-<font face=\"symbol\">b1 foi adicionado às culturas. Os resultados do presente estudo demonstraram que o TGF-<font face=\"symbol\">b1 induz a expressão de <font face=\"symbol\">a-AML, sugerindo a indução do fenótipo miofibroblástico em fibroblastos pulpares. / Transforming growth factor-beta 1 (TGF-<font face=\"symbol\">b1) has been related to induce the expression of <font face=\"symbol\">a-smooth muscle actin (<font face=\"symbol\">a-SMA) in fibroblasts during repair. Since pulpal fibroblasts seem to be somewhat different from other fibroblasts, the present study investigated in vitro whether TGF-<font face=\"symbol\">b1 enhances the expression of <font face=\"symbol\">a-SMA in human pulpal fibroblasts. TGF-<font face=\"symbol\">b1 was added in doses between 5-10 ng/ml to cultures of both dental pulp and gingiva human fibroblasts. The expression of <font face=\"symbol\">a-SMA was analyzed by immunofluorescence and western-blotting. Both cell types were immunoreactive for <font face=\"symbol\">a-SMA even without TGF-<font face=\"symbol\">b1. When TGF-<font face=\"symbol\">b1 was added to cell cultures, the expression of <font face=\"symbol\">a-SMA increased dramatically in pulpal fibroblasts, independent of the concentration used. It was confirmed by the western blot analysis. The present findings showed that TGF-<font face=\"symbol\">b1 up-regulated the expression of <font face=\"symbol\">a-SMA thus inducing pulpal fibroblasts to acquire the myofibroblast phenotype.

Made available in DSpace on 2014-12-17T15:32:29Z (GMT). No. of bitstreams: 1 CassianoFWN_TESE.pdf: 3914655 bytes, checksum: c6fb9bd86bba433eb6a5a047a9337861 (MD5) Previous issue date: 2010-09-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The odontogenic keratocysts are distinguished from other odontogenic cystic lesions by their potentially aggressive clinical behavior and association, in some cases, with Gorlin syndrome. Studies have suggested that syndrome keratocysts, in comparison with sporadic lesions, have higher growth and infiltration capacity and higher recurrence tendency. The aim of this study was to analyze, by means of immunohistochemistry, the expressions of receptor activator of nuclear factor ?B ligand (RANKL) and osteoprotegerin (OPG), the angiogenic index (CD34) and the presence of myofibroblasts (?-SMA) in primary and recurrent sporadic keratocysts and in keratocysts associated with Gorlin syndrome. The sample was composed by 30 sporadic keratocysts (22 primary and 8 recurrent) and 22 syndrome keratocysts. In the epithelium and in the fibrous capsule of the lesions, the immunoexpression of RANKL and OPG was evaluated by determination of the percentage of positive cells, according to the following scores: 0 (less than 10% of positive cells), 1 (11% - 50% of positive cells), 2 (51% - 75% of positive cells) and 3 (more than 76% of positive cells). In addition, cases were classified according to the RANKL score/ OPG score ratio, as follows: RANKL > OPG, RANKL < OPG, and RANKL = OPG. The angiogenic index was analyzed by counting the microvessels immunoreactive to anti-CD34 antibody in 5 fields (200?). The analysis of myofibroblasts was performed by counting the cells immunoreactive to anti-?-SMA antibody in 10 fields (400?). The analysis of the expressions of RANKL and OPG in the epithelial lining and in the fibrous capsule did not reveal significant differences between groups (p > 0.05). Regarding the RANKL/ OPG ratio in the epithelial lining, most sporadic primary (54.5%) and syndrome lesions (59.1%) showed RANKL < OPG ratio and RANKL = OPG ratio, respectively (p > 0.05). With respect to the RANKL/ OPG ratio in the fibrous capsule, the majority of sporadic primary (81.8%) and sporadic recurrent lesions (75.0%) and most syndrome lesions (45.5%) showed RANKL = OPG ratio (p > 0.05). The mean number of microvessels was 69.2 in sporadic primary lesions, 67.6 in recurrent lesions, and 71.6 in syndrome lesions, with no significant differences between groups (p > 0.05). The mean number of myofibroblasts was 34.4 in sporadic primary lesions, 29.3 in recurrent lesions, and 33.7 in syndrome lesions, with no significant differences between groups (p > 0.05). In conclusion, the results of the present study suggest that the differences in the biological behavior between sporadic keratocysts and keratocysts associated with Gorlin syndrome may not be related to the expressions of RANKL and OPG, the RANKL/ OPG ratio, the angiogenic index or the number of myofibroblasts in these lesions / Os ceratocistos odontog?nicos se destacam em rela??o a outras les?es c?sticas odontog?nicas pelo comportamento cl?nico potencialmente agressivo e por se apresentarem associados, em alguns casos, ? s?ndrome de Gorlin. Estudos t?m sugerido que os ceratocistos sindr?micos, em compara??o ?s les?es isoladas, possuem maior capacidade de crescimento e infiltra??o e maior tend?ncia ? recorr?ncia. O objetivo do presente trabalho consistiu em analisar, por meio de imuno-histoqu?mica, as express?es do ligante do receptor ativador do fator nuclear ?B (RANKL) e da osteoprotegerina (OPG), o ?ndice angiog?nico (CD34) e a presen?a de miofibroblastos (?-SMA), em ceratocistos isolados prim?rios e recorrentes e ceratocistos associados ? s?ndrome de Gorlin. A amostra foi composta por 30 ceratocistos isolados (22 prim?rios e 8 recorrentes) e 22 ceratocistos sindr?micos. A express?o de RANKL e OPG foi avaliada no epit?lio e na c?psula fibrosa das les?es, estabelecendo-se o percentual de c?lulas imunopositivas, de acordo com os escores: 0 (? 10% das c?lulas positivas), 1 (11% - 50% das c?lulas positivas), 2 (51% - 75% das c?lulas positivas) e 3 (? 76% das c?lulas positivas). Al?m disso, os casos foram categorizados, segundo a propor??o RANKL/ OPG, em: RANKL > OPG, RANKL < OPG e RANKL = OPG. O ?ndice angiog?nico foi analisado por meio da contagem dos microvasos imunomarcados pelo anticorpo anti-CD34, em 5 campos (200?). Para a avalia??o dos miofibroblastos, foram quantificadas as c?lulas imunorreativas ao anticorpo anti-?-SMA, em 10 campos (400?). A an?lise das express?es de RANKL e OPG, no revestimento epitelial e na c?psula fibrosa, n?o revelou diferen?as significativas entre os grupos (p > 0,05). Em rela??o ? propor??o RANKL/ OPG no revestimento epitelial, grande parte das les?es isoladas prim?rias (54,5%) e sindr?micas (59,1%) exibiu propor??o RANKL < OPG e propor??o RANKL = OPG, respectivamente (p > 0,05). Em rela??o ? propor??o RANKL/ OPG na c?psula fibrosa, a maioria das les?es isoladas prim?rias (81,8%) e isoladas recorrentes (75,0%) e grande parte das les?es associadas ? s?ndrome de Gorlin (45,5%) revelaram propor??o RANKL = OPG (p > 0,05). O n?mero m?dio de microvasos foi de 69,2 nas les?es isoladas prim?rias, 67,6 nas les?es recorrentes e 71,6 nas les?es sindr?micas, sem diferen?as significativas entre os grupos (p > 0,05). A an?lise dos miofibroblastos revelou valores m?dios de 34,4 nas les?es isoladas prim?rias, 29,3 nas les?es recorrentes e 33,7 nas les?es sindr?micas, sem diferen?as significativas entre os grupos (p > 0,05). Em conclus?o, os resultados do presente estudo sugerem que as diferen?as no comportamento biol?gico entre ceratocistos isolados e associados ? s?ndrome de Gorlin podem n?o estar relacionadas ?s express?es de RANKL e OPG, ? propor??o RANKL/ OPG, ao ?ndice angiog?nico ou ? quantidade de miofibroblastos presentes nas les?es

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-18T17:29:53Z No. of bitstreams: 1 fabianaaparecidamayrinkdeoliveira.pdf: 602450 bytes, checksum: 44abccc7edd994e7c93876d1aac063dd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-22T15:11:02Z (GMT) No. of bitstreams: 1 fabianaaparecidamayrinkdeoliveira.pdf: 602450 bytes, checksum: 44abccc7edd994e7c93876d1aac063dd (MD5) / Made available in DSpace on 2016-07-22T15:11:02Z (GMT). No. of bitstreams: 1 fabianaaparecidamayrinkdeoliveira.pdf: 602450 bytes, checksum: 44abccc7edd994e7c93876d1aac063dd (MD5) Previous issue date: 2011-02-24 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Justificativa e Objetivo: Independente da etiologia, a doença renal crônica (DRC) envolve fibrose generalizada e progressiva do tecido, atrofia tubular e a perda da função renal. Atualmente, as terapias eficazes para esta condição são escassas. Neste estudo, foram investigados os efeitos da terapia laser de baixa intensidade (LLLT) sobre a fibrose intersticial, que ocorre após obstrução ureteral unilateral (OUU) em ratos, um modelo experimental de doença renal crônica. Materiais e Métodos: Foram utilizados 32 ratos Wistar, 8 em cada grupo, machos, com 250 a 300g de peso aproximadamente e 8 semanas de idade. O rim obstruído de metade dos ratos, submetidos à OUU receberam dose única intra-operatória do LLLT (AlGaAs laser, 780 nm, 22,5 J / cm ², 30 mW, 30 segundos em cada um dos nove pontos). Após 14 dias, a fibrose renal foi avaliada pela coloração por picrosírius e medição da área transversal sob luz polarizada. Análise imunohistoquímica quantificou células do tecido renal que expressam marcadores de fibroblastos (FSP-1) e miofibroblastos (α-SMA). RT-PCR foi realizado para determinar a expressão de mRNA de genes chaves relacionados com a fibrose: TGF-β1, Smad3 e colágeno I (Col I). Resultados: No grupo OUU e tratado pelo LLLT os animais apresentaram menos fibrose renal do que os animais obstruídos (OUU). α-SMA, TGF-β1 e Smad3 foram aumentados no interstício renal de ratos OUU. LLLT reduziu a expressão de todas essas moléculas. LLLT não parece ter um efeito significativo no Col I ou FSP-1, que também foram induzidos por OUU. Conclusão: Pela primeira vez, nós mostramos que LLLT tem um efeito protetor em relação à fibrose intersticial renal. Entende-se que, atenuando a inflamação, a laserterapia pode impedir a ativação tubular e transdiferenciação, que são os dois processos principais que formam a fibrose renal no modelo OUU. / Background and Objective: Regardless of the etiology, chronic kidney disease (CKD) involves progressive widespread tissue fibrosis, tubular atrophy and loss of kidney function. At present, effective therapies to this condition are lacking. We investigated the effects of low level laser therapy (LLLT) on the interstitial fibrosis that occurs after unilateral ureteral obstruction (UUO) in rats, an experimental model of CKD. Study Design/Materials and Methods: We used 32 Wistar rats, 8 in each group, males, 250 to 300g weight and 8 weeks old. The occluded kidney of half of the Wistar rats that underwent UUO received a single intraoperative dose of LLLT (AlGaAs laser, 780 nm, 22.5 J/cm², 30 mW, 30 seconds on each of nine points). After 14 days, renal fibrosis was assessed by Sirius red staining and measurement of the cross-sectional area under polarized light. Immunohistochemical analyses quantitated the renal tissue cells that expressed fibroblast (FSP-1) and myofibroblast (α-SMA) markers. RT-PCR was performed to determine the mRNA expression of key fibrosis-related genes, namely TGF-β1, Smad3 and collagen I (Col I). Results: The UUO-LLLT animals had less severe renal fibrosis than OUU animals. α- SMA, TGF-β1 and Smad3 were increased in the renal interstitium of UUO rats. LLLT reduced the expression of all of these molecules. LLLT did not appear to have a significant effect on Col I or FSP-1, which were also induced by UUO. Conclusion: For the first time, we showed LLLT had a protective effect regarding renal interstitial fibrosis. It is conceivable that by attenuating inflammation, LLLT can prevent tubular activation and transdifferentiation, which are the two processes that mainly drive the renal fibrosis of the UUO model.

Durante o processo de reparação tecidual, o fator de transformação de crescimento <font face=\"symbol\">b1 (TGF-<font face=\"symbol\">b1) apresenta um importante papel na regulação da expressão da <font face=\"symbol\">a-actina de músculo liso (<font face=\"symbol\">a-AML) e portanto, na diferenciação miofibroblástica. Como os fibroblastos pulpares apresentam características peculiares, com a expressão de proteínas específicas que os diferem de fibroblastos de outros tecidos conjuntivos, o presente estudo avaliou in vitro se o TGF-<font face=\"symbol\">b1 aumenta a expressão de <font face=\"symbol\">a-AML em fibroblastos pulpares humanos comparando-os com fibroblastos de gengiva. Para tal, diferentes doses de TGF-<font face=\"symbol\">b1 (5 à 10 ng/ml) foram adicionadas às culturas de células, sendo a expressão da <font face=\"symbol\">a-AML analisada por imunofluorescência e western-blotting. Ambos os tipos celulares imunoexpressaram <font face=\"symbol\">a-AML mesmo sem o tratamento com o TGF-<font face=\"symbol\">b1, estando aumentada consideravelmente, quando o TGF-<font face=\"symbol\">b1 foi adicionado às culturas. Os resultados do presente estudo demonstraram que o TGF-<font face=\"symbol\">b1 induz a expressão de <font face=\"symbol\">a-AML, sugerindo a indução do fenótipo miofibroblástico em fibroblastos pulpares. / Transforming growth factor-beta 1 (TGF-<font face=\"symbol\">b1) has been related to induce the expression of <font face=\"symbol\">a-smooth muscle actin (<font face=\"symbol\">a-SMA) in fibroblasts during repair. Since pulpal fibroblasts seem to be somewhat different from other fibroblasts, the present study investigated in vitro whether TGF-<font face=\"symbol\">b1 enhances the expression of <font face=\"symbol\">a-SMA in human pulpal fibroblasts. TGF-<font face=\"symbol\">b1 was added in doses between 5-10 ng/ml to cultures of both dental pulp and gingiva human fibroblasts. The expression of <font face=\"symbol\">a-SMA was analyzed by immunofluorescence and western-blotting. Both cell types were immunoreactive for <font face=\"symbol\">a-SMA even without TGF-<font face=\"symbol\">b1. When TGF-<font face=\"symbol\">b1 was added to cell cultures, the expression of <font face=\"symbol\">a-SMA increased dramatically in pulpal fibroblasts, independent of the concentration used. It was confirmed by the western blot analysis. The present findings showed that TGF-<font face=\"symbol\">b1 up-regulated the expression of <font face=\"symbol\">a-SMA thus inducing pulpal fibroblasts to acquire the myofibroblast phenotype.