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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Alterações salivares na disfunção renal crônica em ratos induzida por 5/6 de nefrectomia / Salivary alterations in chronic renal dysfunction in rats induced by 5/6 nephrectomy

Ana Carolina Romero 19 August 2013 (has links)
A saliva é um fluído produzido e secretado pelas glândulas salivares. Ela desempenha um importante papel na homeostase dos indivíduos. Diversas doenças afetam a produção ou a composição da saliva secretada, dentre elas a doença renal crônica (DRC). A DRC é definida como um dano renal ou diminuição da função renal por um período igual ou superior a três meses. É classificada em estágios, sendo que em seu grau mais avançado existe a necessidade de terapias de hemodiálise ou transplante renal. Muitos são os estudos que buscaram manifestações orais, alterações de fluxo e composição salivares nestes pacientes, contudo quando buscamos na literatura, não encontramos trabalhos que utilizaram um modelo animal para o estudo de parâmetros de composição salivar na doença renal crônica. O objetivo deste estudo foi analisar alterações em alguns componentes na saliva de ratos estimulada por pilocarpina (1mg/Kg) ou isoproterenol (5mg/Kg), em um modelo de 5/6 de nefrectomia (IRC), comparando com um grupo controle positivo (Sham) e outro controle negativo (C) em dois tempos experimentais de 8 e 12 semanas. A nefropatia crônica foi obtida com 5/6 de nefrectomia pela ligadura de dois ramos da artéria renal esquerda e nefrectomia total direita e os grupos Sham foram submetidos à simulação do procedimento cirúrgico. Ao final dos tempos experimentais, amostras de sangue e saliva foram coletadas de todos os grupos e foram analisados: fluxo salivar, concentração de proteína total, atividades das enzimas amilase e peroxidase, ácido siálico livre e total, bem como as dos íons: cálcio, fósforo, sódio, potássio e concentração de ureia salivar. Foram analisadas também as concentrações séricas de ureia e creatinina. Observamos aumento significativo das concentrações séricas de ureia e creatinina e das concentrações salivares de ureia nos grupos IRC em ambos os tempos experimentais; Com estímulo de pilocarpina, observamos que com 8 semanas ocorreu diminuição significativa da atividade da enzima amilase e com 12 semanas ocorrem aumentos significativos da concentração de proteínas totais e atividade da enzima peroxidase. No estímulo com isoproterenol, observamos que com 8 semanas ocorrem diminuições significativas das atividades das enzimas amilase e peroxidase, com 12 semanas ocorreu diminuição significativa do fluxo salivar do grupo IRC em relação ao grupo Sham, aumento significativo da atividade da enzima amilase e diminuição significativa da atividade da enzima peroxidase no grupo IRC em relação aos grupos controle e sham. Concluímos que o período de 12 semanas pós-cirurgia apresentou maiores alterações da saliva coletada tanto pelo estímulo simpático quanto pelo estímulo parassimpático, devendo este período ser utilizado nas futuras análises em glândulas salivares. / Saliva is a fluid produced and secreted by the salivary glands. It plays an important role in the homeostasis of individuals. Several diseases affect the production or composition of saliva secreted, among them chronic kidney disease (CKD). CKD is defined as a kidney damage or decreased kidney function for a three months exceeding period. It is classified in stages, and in its most advanced level there is a need for hemodialysis therapies or kidney transplantation. Many studies have sought oral manifestations, changes in salivary flow and composition in these patients, however when we look at the literature, we did not found studies that used an animal model for the study of salivary composition in chronic kidney disease. The aim of this study was to analyze changes in some components in the saliva of rats stimulated by pilocarpine (1mg/Kg) or isoproterenol (5mg/kg) in a model of 5/6 nephrectomy (CRF), compared with a positive control group (Sham) and a negative control (C) at two time period of 8 and 12 weeks. The chronic nephropathy was obtained with 5/6 nephrectomy by ligation of two branches of the left renal artery and right radical nephrectomy and Sham groups underwent surgery simulation. At the end of the experimental period, blood and saliva samples were collected from all groups and were analyzed: salivary flow rate, total protein concentration, activities of amylase and peroxidase, free and total sialic acid, as well as the ions calcium, phosphorus, sodium, potassium and urea concentration in saliva. We also evaluate the serum concentrations of urea and creatinine. We observed a significant increase in serum urea and creatinine concentrations and salivary urea in IRC groups in both experimental times; Under pilocarpine stimulation, we found a significant decrease in the activity of the enzyme amylase 8 weeks after the surgery. 12 weeks after the surgery increase in the total protein concentration and peroxidase activity were observed; Under stimulation with isoproterenol, we observed decreases in the activities of amylase and peroxidase after 8 weeks; 12 weeks after the surgery we found decrease in salivary flow compared to the sham group, increase in the activity of the enzyme amylase and decrease of the peroxidase activity in CRF group when compared to control and sham groups. We conclude that the period of 12 weeks after surgery showed greater changes in saliva collected both by sympathetic stimulation and by parasympathetic stimulation, and this period should be used in future analyzes in salivary glands.
22

A retrospective review with prospective follow up of renal function, blood pressure and proteinuria post living donor nephrectomy at Groote Schuur Hospital, Cape Town South Africa

Murugan, Ashley 16 October 2020 (has links)
Introduction: Renal transplantation is the treatment of choice for patients with end stage renal disease [ESRD]. An increased risk of ESRD has been demonstrated when comparing donors to age matched healthy non-donors. There are no outcome data in Africa on long term donor renal function or mortality. Therefore, this study aimed to assess long term health complications in the living donor population and evaluate risk factors associated with poor health outcomes of the donors. Methods: This was a retrospective review with prospective follow up of persons undergoing living related donor nephrectomy for renal transplantation, at Groote Schuur Hospital (GSH) from January 2005 to November 2017. We retrospectively analysed baseline demographics, clinical information including blood pressure and renal function (creatinine, eGFR and proteinuria) and compared them with follow up blood pressure and renal function. Results: The majority of the donors were of mixed ancestry 94/154(61%) and 1st degree relatives 111/154 (72%) of which 63/111 (56.8%) donors were siblings. Hypertension developed in 16/31 (51.6%) donors at follow-up. Those developing hypertension had a higher mean baseline blood pressure (systolic blood pressure 139±11.3 mmHg and diastolic blood pressure 85.5±7.3 mmHg). 21/49(42.9%) developed chronic kidney disease [CKD], of which, 16 donors had an eGFR < 60 ml/min/1.73m2 . In those that developed CKD there was a higher percentage of males (p=0.018) and they were older (p=0.048) at baseline. Baseline systolic and diastolic blood pressures was not statistically different in those that developed CKD. 3/31(9.6%) donors developed diabetes. Conclusions: In South Africa, CKD is on the rise and the need for kidney donors for patients with ESRD is therefore also increasing. This study demonstrates that our living donors are at increased risk of CKD and hypertension and therefore need to be followed up more rigorously.
23

Studies on kidney pathophysiological analyses in SDT fatty rat, a novel obese diabetic model / 新規肥満糖尿病モデルSDT fattyラットの腎臓病態解析に関する研究

Katsuda, Yoshiaki 24 November 2015 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第12973号 / 論農博第2823号 / 新制||農||1037(附属図書館) / 学位論文||H28||N4955(農学部図書室) / 32411 / 新制||農||1037 / (主査)教授 久米 新一, 教授 今井 裕, 教授 松井 徹 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
24

Vliv ischémie na funkci ledviny - klinický model resekce tumoru solitární ledviny / Impact of Warm Ischemia on Renal Function - Clinical Model of Tumor Resection of Solitary Kidney

Stránský, Petr January 2015 (has links)
Objective: The aim of this work is to evaluate the effect of warm ischemia on renal function. Methods: Within a multicentric study, the data about tumor-affected solitary kidney were obtained from 9 urological centers in the Czech Republic. Patients were divided into groups according to the WIT (warm ischemia time). In each group the mean preoperative serum creatinine was determined, as well as on 3rd and 7th postoperative day and the lowest GF postoperatively. In each group the mean R.E.N.A.L. nephrometric score was determined. Results: The study compriese data totally of 97 patients. The open approach was chosen in 78 cases, in 16 cases laparoscopic approach was chosen. The robotic surgery was performed in 3 patients. PN with zero ischemia was performed in 29 patients (30%). Conclusion: Our findings confirm that non-clamping partial nephrectomy in a solitary kidney minimizes renal injury. For the non-clamping partial nephrectomy can be mainly indicated smaller exophyticall tumors without deep parenchymal invasion. Unfortunately, most of PN should be performed with vascular clamping, allowing precise closure of collecting system, vascular and parenchymal defect, especially for larger tumors with deep parenchymal invasion. According to our observation that WIT of 15 minutes for a kidney is safe. Clamping of...
25

Vliv ischémie na funkci ledviny - klinický model resekce tumoru solitární ledviny / Impact of Warm Ischemia on Renal Function - Clinical Model of Tumor Resection of Solitary Kidney

Stránský, Petr January 2015 (has links)
Objective: The aim of this work is to evaluate the effect of warm ischemia on renal function. Methods: Within a multicentric study, the data about tumor-affected solitary kidney were obtained from 9 urological centers in the Czech Republic. Patients were divided into groups according to the WIT (warm ischemia time). In each group the mean preoperative serum creatinine was determined, as well as on 3rd and 7th postoperative day and the lowest GF postoperatively. In each group the mean R.E.N.A.L. nephrometric score was determined. Results: The study compriese data totally of 97 patients. The open approach was chosen in 78 cases, in 16 cases laparoscopic approach was chosen. The robotic surgery was performed in 3 patients. PN with zero ischemia was performed in 29 patients (30%). Conclusion: Our findings confirm that non-clamping partial nephrectomy in a solitary kidney minimizes renal injury. For the non-clamping partial nephrectomy can be mainly indicated smaller exophyticall tumors without deep parenchymal invasion. Unfortunately, most of PN should be performed with vascular clamping, allowing precise closure of collecting system, vascular and parenchymal defect, especially for larger tumors with deep parenchymal invasion. According to our observation that WIT of 15 minutes for a kidney is safe. Clamping of...
26

Serum levels of fibroblast growth factor-21 are increased in chronic and acute renal dysfunction

Hindricks, Janka 09 October 2015 (has links) (PDF)
The progressively increasing prevalence of the Metabolic Syndrome (MetS) has emerged as a major global health concern since the MetS is associated with an increased risk for cardiovascular morbidity and mortality. Central obesity represents a key feature of the MetS and is strongly related to all MetS comorbidities. Dysregulation of adipose tissue-derived proteins, so called adipokines, has been implied to partially contribute to these effects. Recently, fibroblast growth factor-21 (FGF-21) has been introduced as a novel insulin sensitizing and weight reducing adipokine with potential therapeutic properties. However, data on FGF-21 elimination are rather limited. Therefore, FGF-21 regulation in relation to renal function has been investigated in a patient population with chronic kidney disease (CKD, study population 1), as well as one with acute kidney impairment (study population 2). In study population 1 (n = 499), patients were distributed into five CKD subgroups according to estimated glomerular filtration rate (eGFR). Median FGF-21 serum concentrations progressively increased from CKD stage 1 to stage 5 and highest values of FGF-21 were detected in stage 5 (1: 86.4 ng/l; 2: 206.4 ng/l; 3: 289.8 ng/l; 4: 591.3 ng/l; 5: 1918.1 ng/l). Furthermore, eGFR remained the strongest predictor for FGF-21 levels in multivariate analysis. For study population 2 (n = 32), blood samples were obtained before elective unilateral partial or total nephrectomy, as well as within 30 hours after surgery. In this population FGF-21 levels significantly increased after surgery (325.0 ng/l) as compared to before surgery (255.5 ng/l). Furthermore, relative changes of FGF-21 were independently and positively predicted by relative changes of creatinine in this cohort. These results are in accordance with the hypothesis that FGF-21 is eliminated by the kidneys and that the extent of kidney dysfunction substantially contributes to serum FGF-21 levels. However, additional animal experiments and prospective clinical studies are needed to further elucidate the role of the kidneys in FGF-21 physiology.
27

Development of Salt-Sensitive Hypertension in Hydronephrosis

Carlström, Mattias January 2008 (has links)
<p>Hydronephrosis, due to ureteropelvic junction obstruction, is a common condition in infants with an incidence of approximately 0.5-1%. During the last decade, the surgical management of non-symptomatic hydronephrosis has become more conservative, and the long-term physiological consequences of this new policy are unclear. The overall aim of this thesis was to determine whether there is a link between hydronephrosis and the development of hypertension. Hydronephrosis was induced by partial ureteral obstruction in 3-week old rats or mice. In the adult animals, blood pressure was measured telemetrically during different sodium conditions and the renal function was evaluated. Both species developed salt-sensitive hypertension and histopathological changes (i.e. fibrosis, inflammation, glomerular and tubular changes) that correlated with the degree of hydronephrosis. An abnormal renal excretion pattern with increased diuresis and impaired urine concentrating ability was observed in hydronephrosis. The mechanisms were primarily located to the diseased kidney, as relief of the obstruction attenuated blood pressure and salt-sensitivity. Increased renin angiotensin system activity, due to ureteral obstruction, might be involved in the development but not necessary the maintenance of hypertension. Hydronephrotic animals displayed reduced nitric oxide availability, which might be due to increased oxidative stress in the diseased kidney. Renal nitric oxide deficiency and subsequent resetting of the tubuloglomerular feedback mechanism, appeared to have an important role in the development of hypertension. In conclusion, experimental hydronephrosis, induced by partial ureteral obstruction, provides a new model for studies of salt-sensitive hypertension. Furthermore, the new findings imply that the current conservative treatment strategy in hydronephrosis should be reconsidered in favour of treatment that is more active, in order to prevent the development of renal injury and hypertension in later life.</p>
28

La néphrectomie partielle chez les patients atteints du cancer du rein de stade T1b

Meskawi, Malek 04 1900 (has links)
Objectif : La néphrectomie partielle est reconnue actuellement comme le traitement de choix des tumeurs de moins de 7 cm. Le but de notre étude est de comparer le taux de mortalité lié au cancer du rein suite au traitement par néphrectomie partielle ou radicale chez les patients de stade T1b, de présenter la tendance temporelle du taux d'intervention par néphrectomie partielle pour les tumeurs de stade T1b et d’identifier les facteurs sociodémographiques et tumoraux qui influencent le choix thérapeutique entre les deux types de traitement chirurgical. Méthode : Il s’agit d’une étude épidémiologique de type rétrospective. La population de patients provient de la base de donnée SEER (Surveillance, Epidemiology, and End Results) qui regroupe une grande proportion de la population nord-américaine. Dans notre étude, nous avons utilisé l’analyse par régression logistique pour identifier les facteurs sociodémographiques associés à l'intervention par néphrectomie partielle. Dans un deuxième temps, nous avons comparé la mortalité liée au cancer entre les deux options chirurgicales, après association par score de tendance pour diminuer les différences de base entre les deux populations. Nos critères étaient l’âge, la race, le sexe, l’état civil, le niveau socioéconomique, la taille tumorale, le grade nucléaire, l’histologie et la localité du centre hospitalier. L’analyse des données a été faite par le logiciel SPSS. Résultats : Le taux d'interventions par néphrectomie partielle a augmenté de 1,2% en 1988 à 15,9% en 2008 (p <0,001). Les jeunes patients, les tumeurs de petite taille, les patients de race noire, ainsi que les hommes sont plus susceptibles d'être traités par néphrectomie partielle (tous les p < 0,002). Parmi le groupe ciblé, le taux de mortalité lié au cancer à 5 ans et à 10 ans est de 4,4 et de 6,1% pour les néphrectomies partielles et de 6,0 et 10,4% pour les néphrectomies radicales (p = 0,03). Après ajustement de toutes les autres variables, les analyses de régression montrent que le choix entre les deux types de néphrectomie n’est pas associé à la mortalité lié au cancer (hazard ratio: 0,89, p = 0,5). Conclusion : Malgré un contrôle oncologique équivalent, le taux d'intervention par néphrectomie partielle chez les patients ayant un cancer du rein T1b est faible en comparaison à la néphrectomie radicale. / Objectives: To examine utilization rates of partial nephrectomy relative to radical nephrectomy for T1b renal cell carcinoma in contemporary years, to identify sociodemographic and disease characteristics associated with partial nephrectomy use, and to compare effectiveness of partial vs. radical nephrectomy with respect to cancer control outcomes. Materials and Methods: Using the Surveillance, Epidemiology, and End results database, 16,333 patients treated with partial or radical nephrectomy for T1bN0M0 renal cell carcinoma between 1988 and 2008 were identified. Logistic regression models were performed to identify determinants of partial nephrectomy. Subsequently, cumulative incidence rates of cancer-specific and other-cause mortality between partial and radical nephrectomy were assessed, within the matched cohort. Finally, we relied on competing-risks regression analyses for prediction of cancer-specific mortality, after adjusting for other-cause mortality, and vice-versa. Results: The utilization rate of partial nephrectomy increased from 1.2% in 1988 to 15.9% in 2008 (P<0.001). Younger individuals, smaller tumors, persons of black race, as well as men were more likely to be treated with partial nephrectomy in the current cohort (all P≤0.002). In the post-propensity cohort, the 5- and 10-year cancer-specific mortality rates were 4.4 and 6.1% for partial vs. 6.0 and 10.4% for radical nephrectomy, respectively (P=0.03). Following adjustment for other covariates, competing-risks regression analyses showed that nephrectomy type was not statistically significantly associated with cancer-specific mortality, even after adjusting for other-cause mortality (hazard ratio: 0.89, P=0.5). Conclusions: Despite a comparable cancer control outcome, consideration of partial over radical nephrectomy in T1b renal cell carcinoma individuals remains conservative in recent years.
29

Terapia com células-tronco na nefropatia crônica experimental: é possível bloquear a progressão da doença renal? / Stem celll therapy in experimental chronic nephropathy: is it possible to block the progression of renal disease?

Cavaglieri, Rita de Cássia 08 February 2010 (has links)
Células-tronco (CT) apresentam potencial terapêutico para a doença renal pela possibilidade de regeneração tecidual e recuperação funcional, possivelmente por efeitos parácrinos. Diversos trabalhos mostraram seu efeito renoprotetor em modelo de insuficiência renal aguda. No entanto, existem poucos trabalhos que avaliaram o efeito da CT em doença renal crônica. Neste contexto, a via de inoculação e o número das CT na região da lesão podem desempenhar um papel crucial. Assim, o transplante de CT pela via EV não parece ser o mais apropriado para prover CT em número expressivo no órgão alvo. Uma técnica alternativa consiste em inocular as CT localmente, na região subcapsular renal. O objetivo do presente estudo foi analisar, em modelo experimental de doença renal crônica por nefrectomia 5/6 (Nx), a migração, a distribuição e o possível efeito renoprotetor da inoculação via subcapsular renal de 2 tipos de CT: derivadas da medula óssea (CTdmo) e mesenquimais (CTm). As CT foram coletadas de fêmur e tíbia de ratos doadores através da técnica de flushing. As CTdmo foram isoladas por gradiente de concentração e as CTm pela sua capacidade de aderência ao plástico e ambas marcadas com DAPI para a visualização no tecido. A caracterização das CT foi feita por citometria de fluxo e pela diferenciação celular in vitro. Foram realizados 2 protocolos experimentais. No protocolo I, CTdmo (1x106) foram inoculadas em ratos fêmeas e, no protocolo II, CTm (2x105) foram inoculadas em ratos machos. A região inoculada foi a subcapsula renal e os animais foram acompanhados por 15 e 30 dias. Os animais foram subdivididos nos grupos: Sham, ratos submetidos à cirurgia fictícia; Sham+CT, ratos submetidos à cirurgia fictícia que receberam CT (CTdmo ou CTm); Nx, ratos submetidos a nefrectomia 5/6; Nx+CT, Nx ratos que receberam CT (CTdmo ou CTm). Para avaliar a localização das CTdmo no tecido renal, utilizou-se a coloração de tricrômio de Masson e foi realizada uma análise semiquantitativa para avaliar o grau de infiltração. Foram analisadas a pressão arterial (PA), a albuminúria e a creatinina sérica. Para os animais que receberam CTm foi realizada a análise de parâmetros histológicos e a análise de marcadores inflamatórios, de células em atividade proliferativa, de miofibroblastos e de podócitos. Os resultados do Protocolo I avaliando a análise da infiltração no tecido renal das CTdmo marcadas com DAPI mostrou, em 5 dias, evidente infiltração das células da região subcapsular em sentido ao córtex e medula, inclusive presente em glomérulos. Ratos fêmeas Nx que receberam a inoculação das CTdmo na região da subcapsular renal não apresentaram melhora nos parâmetros que avaliaram a função renal. Protocolo II: as CTm cultivadas mostraram grande capacidade de aderência, crescimento em colônia e de diferenciação em células osteogênicas. A análise por citometria mostrou-se positiva para CD44 e CD90, com uma pequena população de células de CD34, CD45 e CD31, confirmando a presença preponderante de CTm. A inoculação de CTm em ratos Nx proporcionou um bloqueio da progressão da doença renal. Enquanto ratos Nx machos apresentaram elevada PA com 15 e 30 dias (149,6±9,1 e 191,7±2,8 mmHg) a inoculação de CTm promoveu significante redução após 30 dias (145,2±6,8 mmHg; p<0,05 vs Nx). Em ratos Nx foi observado um aumento na creatinina aos 15 e 30 dias (1,13±0,08 e 1,16±0,26 mg/dL) e a inoculação de CTm promoveu uma marcante redução aos 15 dias (0,58±0,03 mg/dL; p<0,05 vs Nx). A albuminúria foi elevada nos ratos Nx aos 15 e 30 dias (41,7±10,8 mg/24h e 138,7±33,6 mg/24h) enquanto os animais do grupo Nx+CTm aos 15 e 30 dias apresentaram diminuição significativa (4,6±1,5 mg/24h e 23,4±7,7 mg/24h; p<0,0001 vs Nx). A glomeruloesclerose do grupo Nx+CTm apresentou aos 30 dias uma redução significativa em relação ao grupo Nx (5,4±2,5% vs 22,0±6,1%, respectivamente; p<0,0001). A análise da fibrose intersticial não revelou diferença após 15 dias e 30 dias no grupo Nx+CTm em relação ao grupo Nx. Com relação ao número de macrófagos, linfócitos e de células em atividade proliferativa, os animais que receberam CTm apresentaram uma discreta diminuição de sua expressão no tecido renal. A expressão de -actina se reduziu significativamente no grupo Nx+CTm. Quanto à expressão de WT-1, específico para podócitos, os animais Nx+CTm tiveram aumento significativo da marcação em relação ao grupo Nx. Em resumo, após a inoculação de CT na região da subcapsula renal, houve marcante migração e distribuição das mesmas em direção à cortical e à medular. A inoculação de CTm proporcionou um efeito renoprotetor no modelo de nefrectomia 5/6. Sendo assim, a inoculação subcapsular renal pode representar uma importante via de inoculação, permitindo assim que um número maior de células atue na proteção da progressão da doença. / Stem cells (SCs) offer therapeutic potential for the treatment of renal diseases, due to the possibility of tissue regeneration and functional recovery. Various studies have shown renoprotection by SCs in experimental models of acute kidney disease. However, only a few studies have studied their effect in chronic kidney disease. The beneficial effect of SCs seems related to their capacity to differentiate or to secrete paracrine/endocrine factors. In this context, the inoculation route or the number of SCs homing in the injured region can play a crucial role. Therefore, transplantation of MSC through the intravenous route does not seem to be best suited for delivery of an important number of cells to the target organ. An alternative technique consists in local delivery of SCs in the subcapsular region of the kidney. The objective of the present study is to analyze the migration, distribution and potential renoprotective effect of the subcapsular inoculation of two types of SC - BSMC and mesenchymal stem cell (MSC) - in an experimental model of chronic kidney disease, the 5/6 nephrectomy (Nx). SCs were collected from the femur and tibia of donor rats by flushing. BSMC were isolated by centrifugation on a concentration gradient and MSCs were isolated by their capacity to adhere to plastic. Both types of SC were stained with DAPI to allow visualization in tissues. SC characterization was carried out by flow cytometry and differentiation in culture. Two experimental procedures were performed. In protocol I, BSMC (106 cells) were injected in female rats and in protocol II, MSCs (2x105 cells) were injected in male rats. Animals were divided into 4 groups: SHAM, sham-operated rats; SHAM+SC, sham-operated rats receiving BSMC or MSCs; Nx, rats undergoing 5/6 nephrectomy; Nx+SC, 5/6 Nx rats receiving BSMC or MSCs. We used Massons Trichrome staining and a semiquantitative analysis according to the degree of infiltration to follow the localization of BSMC in the renal tissue and to quantify their infiltration, respectively. The following parameters were studied: arterial blood pressure (AP), proteinuria (Uprot), albuminuria (Ualb) and serum creatinine (Screat). For the animals receiving SCs, analysis of histology, of inflammatory markers, of proliferating cells and of podocytes was performed. Results from Protocol I assessing DAPI-stained BSMC showed marked infiltration in 5 days from the subcapsular region to the cortex and the medulla, including presence in the glomeruli, over a period of 15 days. Female rats that received subcapsular injection of BSMC did not show improvement of the parameters used to assess kidney function. Protocol II: cultured MSCs demonstrated an ability to adhere to plastic, to grow in colonies and to differentiate in osteogenic cells. Quantitative analysis of cell markers by flow cytometry showed that isolated cells were positive for CD44 and CD90, with a small population of cells positive for CD31, CD34 and CD45, confirming a preponderant presence of MSCs. Inoculation of MSCs in Nx rats blocked the progression of the renal disease. Elevated AP in Nx rats at 15 and 30 days (149.6 ± 9.1 and 191.7 ± 2.8 mm Hg, respectively) was significantly reduced by inoculation of MSCs at 30 days (145.2 ± 6.8 mm Hg, p<0.05 vs Nx). Nx rats showed increased creatinine at 15 and 30 days (1.13 ± 0.08 and 1.16 ± 0.26 mg/dL, respectively) that was significantly reduced by injection of MSCs at 15 days (0.58 ± 0.03 mg/dL, p<0.05 vs Nx). Albuminuria was increased in Nx rats at 15 and 30 days (41.7 ± 10.8 and 138.7 ± 33.6 mg/24h, respectively) and was reduced in the Nx+MSC group at both time points (4.6 ± 1.5, and 23.4 ± 7.7 mg/24h, respectively; p<0.0001 vs Nx). Histologic analysis showed that glomerulosclerosis at 30 days in the Nx+MSC group was significantly reduced as compared to the Nx group (5.4 ± 2.5 % vs 22.0 ± 6.1 %, p<0.0001). Analysis of interstitial fibrosis did not show difference after 15 and 30 days in the Nx+MSC group compared to Nx group. Nx rats receiving MSCs showed slightly decreased inflammation markers, macrophages and lymphocytes, and proliferating cells in the renal tissue when compared to Nx rats. Analysis of myofibroblasts showed a significant decrease in expression of -smooth muscle actin in Nx+MSC rats compared to Nx rats. Podocyte number was analyzed by detection of WT-1, a specific marker. Nx rats receiving MSC had a significantly higher number of podocytes than Nx rats. In conclusion, our results show that after inoculation in the subcapsular region, SCs migrate throughout the cortex in direction of the medulla. Subcapsular inoculation of MSC provides a renoprotective effect in the model of 5/6 nephrectomy. Therefore, subcapsular inoculation could represent an important route of delivery of SCs to the kidney that allows a higher number of cells to act in the protection from progression of the disease.
30

Le rat ZSF1 : un modèle de maladie cardio-rénale associée au syndrome métabolique : Caractérisation par l'utilisation d'un antioxydant, d'un antagoniste des récepteurs des minéralocorticoïdes et d'un inhibiteur de l'aldostérone synthase / ZSF1 rat : a model of chronic cardiac and renal diseases in the context of metabolic syndrome : Characterization with anti-oxidant, mineralocorticoid receptor antagonist and aldosterone synthase inhibitor

Riboulet, William 18 May 2015 (has links)
Chez les patients présentant un syndrome métabolique, le développement des comorbidités cardiaques et rénales associées au diabète de type 2 sont liées à des altérations au niveau vasculaire. Afin d’évaluer l’effet protecteur rénal et cardiaque de nouvelles molécules, le modèle de rat Zucker fatty/Spontaneously hypertensive heart failure F1 hybrid (ZSF1) semblait approprié. Cependant, son développement lent et les impacts rénaux et cardiaques modestes en limitaient son utilisation. Notre but fut d’exacerber ces altérations par deux méthodes. Nous avons d’abord effectué une néphrectomie unilatérale chez le rat ZSF1 et évalué l’évolution des fonctions cardiaque et rénale en fonction de l’âge. Seule une exacerbation de la dysfonction rénale a été mise en évidence. Néanmoins nous avons pu démontrer l’effet protecteur rénal de l’inhibiteur de l’enzyme de conversion de l’angiotensine lisinopril ainsi que d’un composé antioxydant, le bardoxolone. Notre seconde stratégie a consisté à infuser de l’angiotensine II (AngII) à des rats ZSF1. L’hypertension déjà existante dans ce modèle a été fortement accrue, et le niveau d’aldostérone circulante a été significativement augmenté. Dans ce contexte, les fonctions cardiaque et rénale ont été dégradées de manière importante. Enfin nous avons montré que dans ce modèle, un inhibiteur de l’aldostérone synthase induisait une meilleure protection rénale que l’antagoniste des récepteurs à l’aldostérone éplérénone. Nous avons donc mis en évidence que le rat ZSF1-AngII est un modèle de dysfonction cardio-rénale permettant d’évaluer l’effet protecteur de composés sur les fonctions rénale et cardiaque, dans un contexte de syndrome métabolique / In the context of metabolic syndrome, development of Type 2 Diabetes is associated with (and influenced by) cardiac and renal comorbidities linked to micro- and macro-vasculature alterations. To assess the efficacy of new compounds on targeted organs in the context of metabolic syndrome, the Zucker fatty/Spontaneously hypertensive heart failure F1 hybrid (ZSF1) rat model could be suitable assuming cardiorenal alterations would develop in a short timeframe. Actually, the ZSF1 rat model recapitulates features of human metabolic syndrome, but develops relatively late (1year-time) and moderate cardiac and renal dysfunctions. The aim of our work was to exacerbate cardiorenal impairments in terms of onset and extent. Two options were explored. On one hand, unilateral nephrectomy was performed in ZSF1 rats, and cardiac and renal functions were longitudinally assessed. This surgical insult only significantly deteriorated renal function, which was prevented by standard of care, lisinopril and new renal protective agent, bardoxolone. On the other hand, subcutaneous infusion of angiotensin II (AngII) was used in the aim to induce hemodynamic and hormonal stress and thus to enhance cardiorenal impairments. AngII-infused ZSF1 rats displayed significant hypertension and increased levels of circulating aldosterone. Moreover, renal and cardiac functions dropped, concomitantly. We showed in this model that an aldosterone synthase inhibitor induced overall better renal protection than the mineralocorticoid receptor antagonist eplerenone. Our data showed that ZSF1-AngII rat is a suitable model to evaluate the cardio and renoprotective effects of drugs in the context of metabolic syndrome

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