BACKGROUND Adult bone marrow derived MSCs had been explored to treat myocardial infarction (MI) and heart failure, for which various beneficial paracrine effects had been suggested. Since MSCs in vitro express anti-inflammatory cytokines, we tested the hypothesis that changes in the pro-/anti-inflammatory cytokine ratio in the infarct microenvironment may provide such a paracrine mechanism to improve early cardiac function following acute coronary occlusion. / Methods Rats (n=88) underwent acute left coronary artery ligations and were randomized into groups M and C and then injected with culture media or MSCs, respectively. These rats underwent blinded echocardiography to evaluate left ventricular ejection fractions (LVEF). Real Time PCR was used to compare cytokine gene expression for IL-1beta, IL-6, IL-8 (pro-inflammatory) and IL-10 (anti-inflammatory) at various times. Extra-cellular matrix (ECM) deposition and inflammatory cell infiltration were also analyzed. / Results As early as 12 hours, the ratio of pro-/anti-inflammatory cytokine gene expression in group C was significantly lower than group M. Similar results were found at 24 hours, 1 and 2 weeks, respectively. LVEF improved significantly in group C (M=62% vs C=68% at 12 hours* , M=66% vs C=75% at 24 hours*, M=57% vs C=75% at 1 week *, and M=52% vs C=70% at 2 weeks*, *p<0.01). The ratio of MMP-2/TIMP1 levels was lower in the Group C at all time frames, reaching significance at 12 and 24 hours and 2 weeks. In group C, histopathological analysis revealed significantly less ECM deposition (M=1.95% vs C=0.75% at 24 hours*, M=19.30% vs C=9.36% at 1 week*, M=24.46% vs C=7.57% at 2 weeks*, *p<0.01). This was associated with significantly decreased inflammatory cell infiltration after 24 hours. / Conclusions The current data suggests that MSCs therapy decreases the pro-/anti-inflammatory cytokine ratio in the infarct microenvironment. This is associated with improved cardiac function, reduced ECM deposition, and decreased inflammatory cell infiltration. This paracrine mechanism of MSCs therapy may explain the early functional improvement after MI before cell transdifferentiation or other mechanisms takes place.

No description available.

Introdução: Arginina e antioxidantes estão associados à melhora funcional de cicatrização. Formulação enteral suplementada com arginina e antioxidantes tem sido proposta para corrigir déficit nutricional e garantir substratos ideais para uma boa cicatrização. Ainda não existem informações disponíveis sobre os possíveis mecanismos envolvidos. Objetivo: Avaliar o efeito da nutrição enteral suplementada com arginina e antioxidantes sobre o processo de cicatrização de feridas cutâneas em ratos nutridos e previamente desnutridos, em termos de avaliação morfo-estrutural, bioquímica e biologia molecular. Método: Ratos isogênicos, machos, adultos com peso entre 250 a 350 g, foram divididos aleatoriamente em seis grupos. Três grupos foram mantidos nutridos com alimentação com dieta padrão AIN-93M e três grupos foram submetidos ao regime de desnutrição por 14 dias, com perda de peso corpóreo entre 12 e 15% em relação ao peso corpóreo inicial. Após esse período, os grupos de ratos nutridos e os previamente desnutridos, foram submetidos à lesão cutânea dorsal padronizada e gastrostomia. A seguir, os ratos receberam aleatoriamente dieta por via oral, dieta enteral padrão ou dieta enteral suplementada com arginina e antioxidantes por via gastrostomia, durante 14 dias pós-trauma (PT). A área da lesão cutânea no dia do trauma, no 7º e 14º dias PT foram medidas por fotografia digital. No 7º e 14º dias PT, em tecido de granulação cicatricial, por meio de análise histológica, foram avaliadas as variáveis reepitelização, infiltrado inflamatório, recomposição da derme, quantificação do colágeno total e miofibroblastos (imunoistoquímica). Amostras do tecido de granulação, retiradas no 7º dia PT, foram submetidas à análise de expressão gênica de fatores de crescimento (TGF-beta, KGF, PDGF, VEGF) e colágenos (tipo I e III). Resultados: Ratos nutridos apresentaram maior fechamento da lesão cutânea quando comparados aos previamente desnutridos, no 7º e 14º dias PT, independente dos diferentes tipos de dieta administrados por via gastrostomia. No 14º dia PT, ratos nutridos apresentaram maior reepitelização, intensidade de infiltrado inflamatório e recomposição da derme, quando comparados aos ratos previamente desnutridos, independente da oferta de dieta por via oral, dieta enteral padrão e suplementada. Ratos nutridos e previamente desnutridos, no 7º e 14º dias PT, não apresentaram diferença na quantidade de colágeno total e miofibroblastos, independente do tipo de dieta enteral administrada por via gastrostomia. No 7º dia PT, ratos nutridos apresentaram aumento na expressão gênica dos fatores de crescimento TGF-beta e KGF e colágenos I e III, quando comparados aos ratos previamente desnutridos, independente da dieta enteral administrada por via gastrostomia. Conclusões: 1 - Com estado nutricional mantido, a cicatrização ocorre de maneira adequada, independente da dieta oral, enteral padrão ou suplementada. 2- A desnutrição retarda a cicatrização em termos de epitelização, recomposição da derme e contração da ferida cutânea, independente da realimentação com dieta oral, enteral padrão ou suplementada. 3- Após uma semana de trauma cutâneo, a expressão gênica de fatores de crescimento ligados à cicatrização apresentaram-se alterados em virtude da desnutrição prévia, e não foram revertidos independentemente da realimentação com dieta oral, enteral padrão ou suplementada. 4- Após uma semana de trauma cutâneo, a expressão gênica dos colágenos tipo I e III ligados à cicatrização apresentaram-se alterados em virtude da desnutrição prévia, e não foram revertidos independentemente da realimentação com dieta oral, enteral padrão ou suplementada / Introduction: Arginine and antioxidants are associated with functional enhancement of healing. Arginine and antioxidants supplemented enteral formulas have been used to revert nutritional deficits and to guarantee substrates to ideal healing. The possible mechanisms involved have not been totally elucidated. Objective: To examine the effect of enteral nutrition supplemented with arginine and antioxidants on cutaneous wound healing process in nourished and previously malnourished rats in morphological structural, biochemical and molecular analyses. Methods: Isogenic rats, male, adults, weighting 250 to 350 g, were divided in six groups. Three groups were maintained nourished with oral diet AIN-93 and three groups were submitted to malnutrition process for 14 days, with 12 to 15% of body weight loss. Nourished and previously malnourished groups were submitted to dorsal cutaneous wound and gastrostomy. The rats received oral diet, standard enteral diet or enteral diet supplemented with arginine and antioxidants through gastrostomy during 14 days post trauma (PT). The cutaneous wound area on day of trauma, 7th and 14th days post-trauma were calculated. At 7th and 14th day, histological variables (re-epithelization, inflammatory infiltrate, dermal recomposition and total collagen quantification) and myofibroblasts were analyzed at granulation tissue. Growth factors (TGF-beta, KGF, PDGF and VEGF) and collagens (type I and III) gene expression analyses were performed at samples from the granulation tissue. Results: Nourished rats showed higher contraction of cutaneous wound when compared with previously malnourished rats, on 7th and 14th days post trauma (PT) independent of different enteral diet administered through gastrostomy. On 14th day PT, nourished rats showed higher re-epithelization, inflammatory infiltrate intensity and dermal recomposition when compared to previously malnourished rats, independent of physiologic solution, standard enteral diet and supplemented enteral diet with arginine and antioxidants. Total collagen quantification and myofibroblasts semi-quantification, did not show any significant difference, independent of the enteral diet type, administered through gastrostomy in nourished and previously malnourished rats, at 7th and 14th days PT. Nourished rats showed higher levels of TGF-beta, KGF, collagen type I and III gene expression when compared to previously malnourished rats, independent of the enteral diet type administered through gastrostomy at the 7th day PT. Conclusions: 1- Adequate healing process occurs with the maintenance of nutritional status, independent of the feeding of a oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants, 2- Previous malnutrition state slower re-epithelization, dermal recomposition and contraction, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants refeeding. 3- Previous malnutrition reduce the levels of growth factors gene expression involved on wound healing, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants after seven days post-trauma. 4- Previous malnutrition reduce the levels of collagens type I and III gene expression involved on wound healing, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants after seven days post-trauma

Wong Hei Lui. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 192-226). / Abstracts in English and Chinese. / Publications Based On The Work In This Thesis --- p.i / Abstract --- p.ii / Acknowledgements --- p.vii / Abbreviations --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Normal joint --- p.1 / Chapter 1.11 --- Biology of joint --- p.1 / Chapter 1.12 --- Structure of synovial joint --- p.1 / Chapter 1.13 --- Components of the mature synovial joint --- p.3 / Chapter 1.131 --- Articular cartilage --- p.3 / Chapter 1.1311 --- Water --- p.4 / Chapter 1.1312 --- Cartilage matrix --- p.4 / Chapter 1.1313 --- Chondrocyte --- p.5 / Chapter 1.132 --- Synovium --- p.5 / Chapter 1.1321 --- Synovium vasculature --- p.6 / Chapter 1.1322 --- Synovial blood flow --- p.7 / Chapter 1.133 --- Synovial fluid --- p.8 / Chapter 1.134 --- Bone --- p.9 / Chapter 1.2 --- Pathological processes of arthritis --- p.11 / Chapter 1.21 --- Activation of immune cells in arthritis --- p.11 / Chapter 1.22 --- Synovial proliferation --- p.13 / Chapter 1.221 --- Synovial lining cell activation --- p.13 / Chapter 1.222 --- Pannus invasion --- p.14 / Chapter 1.23 --- Cartilage and bone degradation --- p.14 / Chapter 1.231 --- Depletion of proteoglycan (GAG) --- p.15 / Chapter 1.232 --- Collagen denature --- p.15 / Chapter 1.3 --- Tachykinins (TKs) --- p.17 / Chapter 1.31 --- History --- p.17 / Chapter 1.32 --- "Synthesis, storage and release of TKs" --- p.17 / Chapter 1.33 --- Tachykinin receptors --- p.18 / Chapter 1.331 --- Characterization of NK1 receptor --- p.19 / Chapter 1.332 --- Characterization of NK2 receptor --- p.19 / Chapter 1.333 --- Characterization of NK3 receptor --- p.20 / Chapter 1.34 --- Effector systems of TKs --- p.21 / Chapter 1.35 --- Termination of TK signals --- p.21 / Chapter 1.351 --- Enzymatic breakdown --- p.21 / Chapter 1.352 --- Receptor desensitization --- p.22 / Chapter 1.353 --- Receptor endocytosis --- p.22 / Chapter 1.36 --- TK receptor antagonists --- p.23 / Chapter 1.361 --- Selective NK1 receptor antagonists --- p.23 / Chapter 1.362 --- Selective NK2 receptor antagonists --- p.24 / Chapter 1.363 --- Selective NK3 receptor antagonists --- p.25 / Chapter 1.4 --- Roles of tachykinins in arthritis --- p.28 / Chapter 1.41 --- Correlation between tachykinins and joint inflammation --- p.28 / Chapter 1.42 --- Roles of tachykinins in immune cell activation --- p.30 / Chapter 1.43 --- Roles of tachykinins in synovial proliferation --- p.31 / Chapter 1.44 --- Roles of tachykinins in cartilage degradation --- p.32 / Chapter 1.5 --- Animal model of arthritis --- p.33 / Chapter 1.51 --- Instability model --- p.33 / Chapter 1.52 --- Immobilization model --- p.34 / Chapter 1.53 --- Noxious agent-induced model --- p.34 / Chapter 1.531 --- Collagen-induced erosive arthritis --- p.34 / Chapter 1.532 --- Cartilage oligometric matrix protein-induced arthritis --- p.35 / Chapter 1.533 --- Oil-induced arthritis --- p.35 / Chapter 1.534 --- Streptococcal cell wall-induced arthritis --- p.35 / Chapter 1.535 --- Adjuvant-induced arthritis --- p.36 / Chapter 1.536 --- Pristane-induced arthritis --- p.36 / Chapter 1.6 --- Current anti-arthritic therapies --- p.39 / Chapter 1.61 --- Non steroid anti-inflammatory drugs --- p.39 / Chapter 1.62 --- Glucocorticoid --- p.44 / Chapter 1.63 --- Second-line treatment --- p.46 / Chapter 1.631 --- Sulfasalazine --- p.46 / Chapter 1.632 --- Gold salts --- p.47 / Chapter 1 633 --- D-penicillamine --- p.48 / Chapter 1.634 --- Antimalarial --- p.49 / Chapter 1 .635 --- Methotrexate --- p.51 / Chapter 1.64 --- New trends for treatment of arthritis --- p.53 / Chapter 1.641 --- Anti-cytokine therapy --- p.53 / Chapter 1.642 --- Anti-angiogenesis therapy --- p.54 / Chapter 1.7 --- Aims of study --- p.57 / Chapter Chapter 2 --- Material and drugs --- p.62 / Chapter Chapter 3 --- Methodology --- p.62 / Chapter 3.1 --- Animals used and anaesthetization --- p.62 / Chapter 3.2 --- Measurement of plasma protein extravasation --- p.63 / Chapter 3.3 --- Measurement of knee joint sizes --- p.64 / Chapter 3.4 --- Measurement of knee joint blood flow --- p.65 / Chapter 3.5 --- Measurement of histological changes --- p.65 / Chapter 3.51 --- Dissection and fixation --- p.65 / Chapter 3.52 --- Decalcification --- p.66 / Chapter 3.53 --- Processing --- p.66 / Chapter 3.54 --- Embedding --- p.67 / Chapter 3.55 --- Sectioning --- p.67 / Chapter 3.56 --- Staining --- p.69 / Chapter 3.6 --- Data analysis --- p.69 / Chapter 3.61 --- Scoring systems --- p.72 / Chapter Chapter 4 --- A model of monoarthritis in rats --- p.72 / Chapter 4.1 --- Introduction --- p.72 / Chapter 4.2 --- Method --- p.73 / Chapter 4.3 --- Results --- p.73 / Chapter 4.31 --- Lewis rats --- p.73 / Chapter 4.32 --- Sprague-Dawley (SD) rats --- p.74 / Chapter 4.33 --- Comparison of FCA-induced changes in Lewis and SD rats --- p.74 / Chapter 4.34 --- Histological studies on arthritic SD rats --- p.75 / Chapter 4.4 --- Discussion --- p.93 / Chapter 4.5 --- Conclusions --- p.95 / Chapter Chapter 5 --- Effect of Substance P on adjuvant-induced arthritis --- p.96 / Chapter 5.1 --- Introduction --- p.96 / Chapter 5.2 --- Method --- p.98 / Chapter 5.3 --- Results --- p.99 / Chapter 5.31 --- Evans blue extravasation --- p.99 / Chapter 5.32 --- Joint size --- p.100 / Chapter 5.33 --- Knee joint blood flow --- p.101 / Chapter 5.34 --- Histology results --- p.102 / Chapter 5.341 --- Infiltration of immune cells in synovial tissue --- p.102 / Chapter 5.342 --- Synovial tissue proliferation --- p.102 / Chapter 5.343 --- Cartilage degradation --- p.103 / Chapter 5.344 --- Bone degradation --- p.103 / Chapter 5.4 --- Discussion --- p.120 / Chapter 5.5 --- Conclusions --- p.125 / Chapter Chapter 6 --- Effects of tachykinin receptor antagonists on FCA-induced arthritis / Chapter 6.1 --- Introduction --- p.126 / Chapter 6.2 --- Method --- p.128 / Chapter 6. 21 --- Intravenous NK1 receptor antagonists on FCA-induced arthritis --- p.128 / Chapter 6. 22 --- Intraperitoneal TK receptor antagonists on FCA-induced arthritis --- p.128 / Chapter 6.3 --- Results --- p.129 / Chapter 6.31 --- Intravenous NK1 227}0اreceptor antagonists on FCA-induced arthritis Evans blue extravasation and joint swelling --- p.129 / Chapter 6.32 --- Intraperitoneal tachykinin receptor antagonists on FCA- induced arthritis Evans blue extravasation and joint swelling --- p.129 / Chapter 6.33 --- Intraperitoneal tachykinin receptor antagonists on FCA- induced immune cell accumulation --- p.130 / Chapter 6.34 --- Intraperitoneal tachykinin receptor antagonists on FCA- induced synovial tissue proliferation --- p.131 / Chapter 6.35 --- Intraperitoneal tachykinin receptor antagonists on FCA- induced cartilage degration and bone erosion --- p.131 / Chapter 6.4 --- Discussion --- p.159 / Chapter 6.5 --- Conclusions --- p.162 / Chapter Chapter 7 --- Individual and combined effects of dexamethasone and TK receptor antagonists on FCA-induced arthritis --- p.163 / Chapter 7.1 --- Introduction --- p.163 / Chapter 7.2 --- Method --- p.166 / Chapter 7.3 --- Results --- p.167 / Chapter 7.31 --- Evans blue extravasation --- p.167 / Chapter 7.32 --- Knee joint size --- p.167 / Chapter 7.33 --- Body weight --- p.168 / Chapter 7.34 --- Cellular infiltration --- p.168 / Chapter 7.35 --- Synovial tissue proliferation --- p.168 / Chapter 7.36 --- Cartilage degradation --- p.169 / Chapter 7.4 --- Discussion --- p.184 / Chapter 7.5 --- Conclusions --- p.187 / Chapter Chapter 8 --- General discussions and conclusions --- p.188 / References --- p.192

Introdução: Arginina e antioxidantes estão associados à melhora funcional de cicatrização. Formulação enteral suplementada com arginina e antioxidantes tem sido proposta para corrigir déficit nutricional e garantir substratos ideais para uma boa cicatrização. Ainda não existem informações disponíveis sobre os possíveis mecanismos envolvidos. Objetivo: Avaliar o efeito da nutrição enteral suplementada com arginina e antioxidantes sobre o processo de cicatrização de feridas cutâneas em ratos nutridos e previamente desnutridos, em termos de avaliação morfo-estrutural, bioquímica e biologia molecular. Método: Ratos isogênicos, machos, adultos com peso entre 250 a 350 g, foram divididos aleatoriamente em seis grupos. Três grupos foram mantidos nutridos com alimentação com dieta padrão AIN-93M e três grupos foram submetidos ao regime de desnutrição por 14 dias, com perda de peso corpóreo entre 12 e 15% em relação ao peso corpóreo inicial. Após esse período, os grupos de ratos nutridos e os previamente desnutridos, foram submetidos à lesão cutânea dorsal padronizada e gastrostomia. A seguir, os ratos receberam aleatoriamente dieta por via oral, dieta enteral padrão ou dieta enteral suplementada com arginina e antioxidantes por via gastrostomia, durante 14 dias pós-trauma (PT). A área da lesão cutânea no dia do trauma, no 7º e 14º dias PT foram medidas por fotografia digital. No 7º e 14º dias PT, em tecido de granulação cicatricial, por meio de análise histológica, foram avaliadas as variáveis reepitelização, infiltrado inflamatório, recomposição da derme, quantificação do colágeno total e miofibroblastos (imunoistoquímica). Amostras do tecido de granulação, retiradas no 7º dia PT, foram submetidas à análise de expressão gênica de fatores de crescimento (TGF-beta, KGF, PDGF, VEGF) e colágenos (tipo I e III). Resultados: Ratos nutridos apresentaram maior fechamento da lesão cutânea quando comparados aos previamente desnutridos, no 7º e 14º dias PT, independente dos diferentes tipos de dieta administrados por via gastrostomia. No 14º dia PT, ratos nutridos apresentaram maior reepitelização, intensidade de infiltrado inflamatório e recomposição da derme, quando comparados aos ratos previamente desnutridos, independente da oferta de dieta por via oral, dieta enteral padrão e suplementada. Ratos nutridos e previamente desnutridos, no 7º e 14º dias PT, não apresentaram diferença na quantidade de colágeno total e miofibroblastos, independente do tipo de dieta enteral administrada por via gastrostomia. No 7º dia PT, ratos nutridos apresentaram aumento na expressão gênica dos fatores de crescimento TGF-beta e KGF e colágenos I e III, quando comparados aos ratos previamente desnutridos, independente da dieta enteral administrada por via gastrostomia. Conclusões: 1 - Com estado nutricional mantido, a cicatrização ocorre de maneira adequada, independente da dieta oral, enteral padrão ou suplementada. 2- A desnutrição retarda a cicatrização em termos de epitelização, recomposição da derme e contração da ferida cutânea, independente da realimentação com dieta oral, enteral padrão ou suplementada. 3- Após uma semana de trauma cutâneo, a expressão gênica de fatores de crescimento ligados à cicatrização apresentaram-se alterados em virtude da desnutrição prévia, e não foram revertidos independentemente da realimentação com dieta oral, enteral padrão ou suplementada. 4- Após uma semana de trauma cutâneo, a expressão gênica dos colágenos tipo I e III ligados à cicatrização apresentaram-se alterados em virtude da desnutrição prévia, e não foram revertidos independentemente da realimentação com dieta oral, enteral padrão ou suplementada / Introduction: Arginine and antioxidants are associated with functional enhancement of healing. Arginine and antioxidants supplemented enteral formulas have been used to revert nutritional deficits and to guarantee substrates to ideal healing. The possible mechanisms involved have not been totally elucidated. Objective: To examine the effect of enteral nutrition supplemented with arginine and antioxidants on cutaneous wound healing process in nourished and previously malnourished rats in morphological structural, biochemical and molecular analyses. Methods: Isogenic rats, male, adults, weighting 250 to 350 g, were divided in six groups. Three groups were maintained nourished with oral diet AIN-93 and three groups were submitted to malnutrition process for 14 days, with 12 to 15% of body weight loss. Nourished and previously malnourished groups were submitted to dorsal cutaneous wound and gastrostomy. The rats received oral diet, standard enteral diet or enteral diet supplemented with arginine and antioxidants through gastrostomy during 14 days post trauma (PT). The cutaneous wound area on day of trauma, 7th and 14th days post-trauma were calculated. At 7th and 14th day, histological variables (re-epithelization, inflammatory infiltrate, dermal recomposition and total collagen quantification) and myofibroblasts were analyzed at granulation tissue. Growth factors (TGF-beta, KGF, PDGF and VEGF) and collagens (type I and III) gene expression analyses were performed at samples from the granulation tissue. Results: Nourished rats showed higher contraction of cutaneous wound when compared with previously malnourished rats, on 7th and 14th days post trauma (PT) independent of different enteral diet administered through gastrostomy. On 14th day PT, nourished rats showed higher re-epithelization, inflammatory infiltrate intensity and dermal recomposition when compared to previously malnourished rats, independent of physiologic solution, standard enteral diet and supplemented enteral diet with arginine and antioxidants. Total collagen quantification and myofibroblasts semi-quantification, did not show any significant difference, independent of the enteral diet type, administered through gastrostomy in nourished and previously malnourished rats, at 7th and 14th days PT. Nourished rats showed higher levels of TGF-beta, KGF, collagen type I and III gene expression when compared to previously malnourished rats, independent of the enteral diet type administered through gastrostomy at the 7th day PT. Conclusions: 1- Adequate healing process occurs with the maintenance of nutritional status, independent of the feeding of a oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants, 2- Previous malnutrition state slower re-epithelization, dermal recomposition and contraction, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants refeeding. 3- Previous malnutrition reduce the levels of growth factors gene expression involved on wound healing, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants after seven days post-trauma. 4- Previous malnutrition reduce the levels of collagens type I and III gene expression involved on wound healing, independent of refeeding with oral diet, standard enteral diet or supplemented enteral diet with arginine and antioxidants after seven days post-trauma

Estudos com células tronco mesenquimais (CTm) têm despertado grande interesse devido a seu promissor potencial terapêutico e representam uma alternativa para o tratamento de diversas patologias em diferentes órgãos, inclusive em transplante renal. A rejeição crônica é um dos maiores desafios no transplante tardio e se caracteriza por perda progressiva da função renal causado pela intensa fibrogênese no aloenxerto. Os tratamentos convencionais com imunossupressores, apesar de reduzirem significativamente as crises de rejeição aguda, não interferem na sobrevida do enxerto a longo prazo. A compreensão dos processos fisiopatológicos da doença depende de seu estudo em modelos experimentais, que são de grande importância pois também propiciam uma melhor compreensão dos possíveis tratamentos. O presente estudo teve como objetivo analisar a terapia com células-tronco mesenquimais derivadas de tecido adiposo (CTmTA) no modelo experimental de transplante renal em ratos, para estudar seu efeito na rejeição crônica e avaliar seu potencial efeito imunomodulador. O modelo foi estabelecido com ratos das linhagens isogênicas Fisher (doador) e Lewis (receptor) e os animais transplantados foram divididos em três grupos: ISO (transplante isogênico de Lewis para Lewis, n=6), ALO (transplante alogênico de Fisher para Lewis, n=6) e ALO+CTmTA (transplante alogênico, tratado com CTmTA, n=6). As CTmTA foram caracterizadas por aderência ao plástico, diferenciação nas linhagens adipogênica, condrogênicas e osteogênicas e por citometria de fluxo. Foram inoculadas 1 x 106 células na região subcapsular renal no dia da realização da nefrectomia unilateral direita (10 dias pós-transplante). Após 6 meses foram realizadas análises dos parâmetros clínicos e laboratoriais, além de análise histológica, imunohistoquímica e PCR em tempo real. As CTmTA foram eficientes em prevenir significativamente a elevação da ureia e da creatinina séricas, manter clearence de creatinina em níveis normais, e prevenir a elevação da fração de excreção de Na+ e K+. Além disso, impediram o desenvolvimento de proteinúria e da hipertensão arterial. A análise histológica mostrou uma redução significativa do infiltrado inflamatório de macrófagos e linfócitos T, além de uma diminuição da fibrose intersticial no grupo ALO+CTmTA. O tratamento com CTmTA reduziu significativamente a expressão relativa dos fatores e citocinas pró-inflamatórios tais como INF-y, TNF-alfa, IL1beta e IL-6, além de aumento importante na expressão de IL-4 e IL-10, conhecidas por seu potencial antiinflamatório. Em conclusão, o tratamento com ADMSC em um modelo experimental de transplante renal pode trazer uma nova abordagem terapêutica para controle da rejeição crônica do enxerto. A aparente modulação da resposta imune observada neste trabalho, pode estar associada a uma possível polarização de macrófagos e células T. Outros estudos pré-clínicos e clínicos são necessários para confirmar nossos resultados / Studies involving mesenchymal stem cells (MSCs) have aroused great interest due to their promising therapeutic potential representing an alternative for the treatment of several pathologies in different organs, including renal transplantation. Chronic rejection is one of the major challenges in late transplantation and is characterized by progressive loss of renal function caused by intense fibrogenesis in the allograft. Conventional immunosuppressive treatments, while significantly reducing acute rejection crises, do not interfere with long-term graft survival. Animal model of kidney transplantation can provide a better understanding of the pathophysiological processes and bring a new path to treat chronic rejection. The aim of this project was to analyze the therapy with mesenchymal stem cells derived from adipose tissue (ADMSCs) in the experimental model of kidney transplantation in rats, focus on chronic rejection and evaluate its potential immunomodulatory effect. The model was established with rats of isogenic strains Fisher (donor) and Lewis (recipient), and the transplanted animals were divided into three groups: ISO (isogenic transplantation from Lewis to Lewis, n = 6), ALO (allogenic transplant from Fisher to Lewis, n = 6) and ALO + ADMSCs (allogenic transplantation, treated with ADMSCs, n = 6). ADMSCs were characterized by adhesion to plastic, differentiation in adipogenic, condrogenic and osteogenic lines and by flow cytometry. One million of cells were inoculated under the renal capsule on the day of the right unilateral nephrectomy (10 days after transplantation). After 6 months, clinical and laboratory parameters were analyzed, as well as histological analysis, immunohistochemistry and real-time PCR. ADMSCs were effective in preventing elevation of serum urea and creatinine, elevation of the Na + and K + excretion fraction as well as maintained creatinine clearence at normal levels. Furthermore, the treatment also prevented the development of proteinuria and preserved blood pressure. Histological analysis showed a significant reduction of macrophages and T cells infiltrate, associated to a decreased of interstitial fibrosis in the ALO + ADMSCs group. In the presence of ADMSCs, there was a significant decrease in the relative expression of INF-y, TNF-alpha, IL1beta and IL-6 factors and pro-inflammatory cytokines, as well as a significant increase in the relative expression of anti-inflammatory cytokines as IL-4 and IL-10. In conclusion, treatment with ADMSC in a transplantation model could open a new approach to control chronic rejection. This apparent modulation of the immune response may be associated with a possible polarization of macrophages and T cells. Further pre-clinical and clinical studies are needed to confirm our findings

Estudos com células tronco mesenquimais (CTm) têm despertado grande interesse devido a seu promissor potencial terapêutico e representam uma alternativa para o tratamento de diversas patologias em diferentes órgãos, inclusive em transplante renal. A rejeição crônica é um dos maiores desafios no transplante tardio e se caracteriza por perda progressiva da função renal causado pela intensa fibrogênese no aloenxerto. Os tratamentos convencionais com imunossupressores, apesar de reduzirem significativamente as crises de rejeição aguda, não interferem na sobrevida do enxerto a longo prazo. A compreensão dos processos fisiopatológicos da doença depende de seu estudo em modelos experimentais, que são de grande importância pois também propiciam uma melhor compreensão dos possíveis tratamentos. O presente estudo teve como objetivo analisar a terapia com células-tronco mesenquimais derivadas de tecido adiposo (CTmTA) no modelo experimental de transplante renal em ratos, para estudar seu efeito na rejeição crônica e avaliar seu potencial efeito imunomodulador. O modelo foi estabelecido com ratos das linhagens isogênicas Fisher (doador) e Lewis (receptor) e os animais transplantados foram divididos em três grupos: ISO (transplante isogênico de Lewis para Lewis, n=6), ALO (transplante alogênico de Fisher para Lewis, n=6) e ALO+CTmTA (transplante alogênico, tratado com CTmTA, n=6). As CTmTA foram caracterizadas por aderência ao plástico, diferenciação nas linhagens adipogênica, condrogênicas e osteogênicas e por citometria de fluxo. Foram inoculadas 1 x 106 células na região subcapsular renal no dia da realização da nefrectomia unilateral direita (10 dias pós-transplante). Após 6 meses foram realizadas análises dos parâmetros clínicos e laboratoriais, além de análise histológica, imunohistoquímica e PCR em tempo real. As CTmTA foram eficientes em prevenir significativamente a elevação da ureia e da creatinina séricas, manter clearence de creatinina em níveis normais, e prevenir a elevação da fração de excreção de Na+ e K+. Além disso, impediram o desenvolvimento de proteinúria e da hipertensão arterial. A análise histológica mostrou uma redução significativa do infiltrado inflamatório de macrófagos e linfócitos T, além de uma diminuição da fibrose intersticial no grupo ALO+CTmTA. O tratamento com CTmTA reduziu significativamente a expressão relativa dos fatores e citocinas pró-inflamatórios tais como INF-y, TNF-alfa, IL1beta e IL-6, além de aumento importante na expressão de IL-4 e IL-10, conhecidas por seu potencial antiinflamatório. Em conclusão, o tratamento com ADMSC em um modelo experimental de transplante renal pode trazer uma nova abordagem terapêutica para controle da rejeição crônica do enxerto. A aparente modulação da resposta imune observada neste trabalho, pode estar associada a uma possível polarização de macrófagos e células T. Outros estudos pré-clínicos e clínicos são necessários para confirmar nossos resultados / Studies involving mesenchymal stem cells (MSCs) have aroused great interest due to their promising therapeutic potential representing an alternative for the treatment of several pathologies in different organs, including renal transplantation. Chronic rejection is one of the major challenges in late transplantation and is characterized by progressive loss of renal function caused by intense fibrogenesis in the allograft. Conventional immunosuppressive treatments, while significantly reducing acute rejection crises, do not interfere with long-term graft survival. Animal model of kidney transplantation can provide a better understanding of the pathophysiological processes and bring a new path to treat chronic rejection. The aim of this project was to analyze the therapy with mesenchymal stem cells derived from adipose tissue (ADMSCs) in the experimental model of kidney transplantation in rats, focus on chronic rejection and evaluate its potential immunomodulatory effect. The model was established with rats of isogenic strains Fisher (donor) and Lewis (recipient), and the transplanted animals were divided into three groups: ISO (isogenic transplantation from Lewis to Lewis, n = 6), ALO (allogenic transplant from Fisher to Lewis, n = 6) and ALO + ADMSCs (allogenic transplantation, treated with ADMSCs, n = 6). ADMSCs were characterized by adhesion to plastic, differentiation in adipogenic, condrogenic and osteogenic lines and by flow cytometry. One million of cells were inoculated under the renal capsule on the day of the right unilateral nephrectomy (10 days after transplantation). After 6 months, clinical and laboratory parameters were analyzed, as well as histological analysis, immunohistochemistry and real-time PCR. ADMSCs were effective in preventing elevation of serum urea and creatinine, elevation of the Na + and K + excretion fraction as well as maintained creatinine clearence at normal levels. Furthermore, the treatment also prevented the development of proteinuria and preserved blood pressure. Histological analysis showed a significant reduction of macrophages and T cells infiltrate, associated to a decreased of interstitial fibrosis in the ALO + ADMSCs group. In the presence of ADMSCs, there was a significant decrease in the relative expression of INF-y, TNF-alpha, IL1beta and IL-6 factors and pro-inflammatory cytokines, as well as a significant increase in the relative expression of anti-inflammatory cytokines as IL-4 and IL-10. In conclusion, treatment with ADMSC in a transplantation model could open a new approach to control chronic rejection. This apparent modulation of the immune response may be associated with a possible polarization of macrophages and T cells. Further pre-clinical and clinical studies are needed to confirm our findings