Le faible poids de naissance et/ou une accélération de la croissance pondérale durant l’enfance sont reconnus actuellement comme facteur de risque de maladies cardiovasculaires (hypertension artérielle, en particulier). Leur rôle dans la progression des maladies rénales chroniques de l’adulte est moins évident. Cette association entre un faible poids de naissance et un risque accru d’hypertension artérielle (HTA) à l’âge adulte ferait intervenir une réduction du nombre de néphrons. Ce déficit néphronique, associé au faible poids de naissance, est responsable d’une hyperfiltration glomérulaire au sein de chaque néphron. Ce mécanisme adaptatif entraîne au fil du temps des lésions rénales, une protéinurie, une insuffisance rénale chronique et une véritable hypertension artérielle. Mais l’hypothèse pathogénique du déficit néphronique reste discutable. De plus peu l’influence de la nutrition postnatale précoce a été très peu étudiée chez l’animal. A travers 2 modèles de restriction de croissance intra-utérine (RCIU) chez le rat, nous avons montré que, plus que la RCIU elle-même, le devenir vasculaire et rénal chez le rat RCIU dépend de la sévérité du déficit néphronique. Un déficit néphronique modéré n’est pas suffisant pour affecter à long terme les fonctions/structures vasculaires et rénales chez le rat RCIU obtenu par une restriction protéique maternelle modérée (caséine 9 %)Nous avons également validé un modèle de rattrapage pondéral précoce, chez le rat. Nous avons montré qu’un rattrapage pondéral et/ou une croissance exagérée durant la période néonatale jouent un rôle primordial sur la pression artérielle, les fonctions et la structure rénale à l’âge adulte. Ces paramètres étaient d’autant plus affectés que la suralimentation néonatale était associé à une RCIU. Les maladies vasculaires et rénales résulteraient, en grande partie, d’une inadéquation entre le nombre de néphrons, réduit lors d’un faible poids de naissance, et la nutrition néonatale/postnatale, surabondante.Chez l’homme, la mise en place de nouvelles cohortes est nécessaire afin de mieux comprendre le rôle de la nutrition durant différentes phases de croissance (fœtale, néonatale, enfance et adolescence) dans le développement des maladies chroniques de l’adulte. Ces études devraient évaluer la pertinence de marqueurs précoces, et permettre la mise en œuvre de stratégies préventives précoces nutritionnelles ou médicamenteuses chez les personnes les plus à risques. / Evidence suggest that low birth weight and/or postnatal catch-up growth increase the risk for long term cardiovascular diseases (hypertension especially). Their role on the progression of chronic kidney disease is less evident. The mechanism is incompletely known. Nephron number deficit, associated with low birth weight, may play an important role. In such a condition, an adaptative single nephron glomerular hyperfiltration to meet excretory demands may lead overtime to renal damages. However this hypothesis is still questionable.In the rat, through two experimental models of intrauterine growth restriction (IUGR), we have shown that adverse long term vascular and renal functions are highly dependent on the severity of nephron number deficit. Moreover, we have demonstrated that a rapid neonatal catch-up growth plays a determinant role. Neonatal overfeeding and a high protein diet following IUGR accelerate the expression of hypertension and the progression of chronic kidney disease. Long term vascular and renal diseases may thus result from a mismatch between adverse fetal environment and postnatal beneficial environment. In human prospective epidemiological studies are needed with the aim to evaluate the effect of postnatal nutrition and to determine early markers for future preventive studies.

O diabetes mellitus (DM) é a principal causa de doença renal crônica (DRC) em vários países do mundo. Para pacientes diabéticos com DRC estágio 5 e indicação da terapia renal substitutiva, o transplante (Tx) renal representa uma modalidade terapêutica com técnica bem estabelecida e com excelentes resultados. O transplante simultâneo de rim-pâncreas (TSRP), uma alternativa mais recente praticada em um número mais restrito de centros, apresenta resultados positivos adicionais no controle metabólico, na qualidade de vida e nas complicações crônicas do diabetes. Entretanto, está associado a um risco maior de complicações pós-operatórias e maior número de internações. Tanto o transplante renal quanto o TSRP estão associados a melhor sobrevida do paciente em relação à diálise. A escolha da melhor modalidade de transplante para o paciente diabético com DRC ainda não está clara. O objetivo deste estudo foi analisar os resultados de diferentes modalidades de transplante em pacientes diabéticos com DRC estágio 5, realizados em 3 Centros Brasileiros de Transplante. Assim, analisar a sobrevida do paciente e do enxerto renal após 1, 5 e 8 anos em pacientes DM tipo 1 submetidos a TSRP comparados com transplante renal isolado com doador vivo (DM1-DV) ou transplante de renal isolado com doador falecido (DM1-DF) (Estudo de 3 modalidades de Tx em DM tipo1). Além disso, avaliar em pacientes DM tipo 2, os resultados do transplante renal realizado com doador vivo (DM2-DV) ou doador falecido (DM2-DF) comparados com pacientes DM tipo 1 submetidos ao transplante renal com doador vivo (DM1-DV) ou doador falecido (DM1-DF) (Estudo do Tx em DM tipo 2 vs DM tipo1). Os transplantes foram realizados em 3 Centros de Transplante (Hospital Beneficência Portuguesa, Hospital do Rim e Santa Casa de Porto Alegre). No \"Estudo de 3 modalidades de Tx em DM tipo 1\", foram incluídos 372 transplantes, sendo 262 TSRP, 78 DM1-DV e 32 DM1-DF. No \"Estudo do Tx em DM tipo 2 vs DM tipo 1\", foram incluídos 254 transplantes, sendo 78 DM1-DV, 32 DM1-DF, 61 DM2-DV, 83 DM2-DF. As curvas de sobrevida do paciente e do enxerto renal (Kaplan-Meyer) foram calculadas 1, 5 e 8 anos após o transplante. No \"Estudo de 3 modalidades de Tx em DM tipo 1\", a sobrevida do paciente de receptores de DM1-DV foi significativamente superior comparada com a sobrevida dos receptores de DM1-DF e TSRP no 1º ano (98,7%, 87,5% e 83,2%, respectivamente; p < 0,05) e no 5º ano pós-Tx (90,5%, 70% e 77%, respectivamente; p < 0,05). Não foi observada diferença entre a sobrevida dos pacientes do grupo DM1-DV e TSRP em 8 anos. A sobrevida do enxerto renal foi superior nos receptores DM1-DV no 1º ano pós-Tx, quando comparada com a sobrevida dos receptores DM1-DF e TSRP (96,1%, 84,4% e 80,2%, respectivamente; p < 0,05). Após 5 e 8 anos, a sobrevida do enxerto renal foi semelhante entre os grupos. Ocorreram 90 óbitos durante o período de estudo sendo as principais causas, a infecção (50%) e doença cardiovascular (22%). Óbito com enxerto funcionante e nefropatia crônica do enxerto foram as principais causas de perda do enxerto renal. No \"Estudo do Tx em DM tipo 2 vs DM tipo 1\", como esperado, os pacientes DM tipo 1 eram mais jovens em relação aos pacientes DM tipo 2 (mediana 37,5 e 55 anos, respectivamente; p < 0,0001). Os pacientes transplantados com doador falecido permaneceram maior tempo em tratamento dialítico pré-transplante (mediana 36 meses em DM1-DF e 36 meses em DM2-DF) comparados com pacientes transplantados com doador vivo (mediana 14 meses em DM1-DV e 18 meses em DM2-DV; p < 0,0001). Em pacientes com DM tipo 2, a sobrevida do paciente em 1, 5 e 8 anos nos pacientes DM2-DV foi 95,1%, 87,9% e 81,8%, respectivamente, significativamente maior do que nos pacientes DM2-DF (74,7%, 59,4% e 48,5%, respectivamente; p < 0,01). Em pacientes com DM tipo 1, a sobrevida do paciente em 1, 5 e 8 anos foi 98,7%, 90,5% e 82,1%, respectivamente, significativamente maior do que nos pacientes DM1-DV que nos pacientes DM1-DF (87,5%, 70% e 66,3%, respectivamente; p < 0,01). Comparando-se a sobrevida dos pacientes DM tipo 2 em relação aos DM tipo 1 submetidos a transplante com um mesmo tipo de doador, não foi observado diferença estatisticamente significante. Pacientes do grupo DM2-DV e pacientes DM1-DV apresentaram sobrevidas semelhantes. A sobrevida dos pacientes DM2-DF encontrada foi inferior em relação aos pacientes DM1-DF, porém sem diferença estatística. Em pacientes com DM tipo 2, a sobrevida do enxerto renal em 1, 5 e 8 anos nos pacientes DM2-DV foi 91,8%, 81,2% e 75,3%, respectivamente, significativamente maior do que nos pacientes DM2-DF (73,5%, 54,9% e 44.3%, respectivamente; p < 0,01). Em pacientes com DM tipo 1, a sobrevida do enxerto renal em 1, 5 e 8 anos nos pacientes DM1-DV foi 96,1%, 80,8% e 72,3%, respectivamente, significativamente maior do que nos pacientes DM1-DF (84,4%, 66,8% e 59,3%, respectivamente; p < 0,01) apenas no primeiro ano. Ocorreram 52 óbitos em pacientes DM tipo 2 sendo a infecção principal causa de óbito nos pacientes DM2-DF e a doença cardiovascular a principal causa de óbito nos DM2-DV. Ocorreram 23 óbitos no grupo de pacientes DM tipo 1 e a principal causa foi infecção nos pacientes DM1-DF e a doença cardiovascular nos DM1-DV. A principal causa de perda do enxerto renal foi óbito com enxerto funcionante (74%), seguido pela nefropatia crônica do enxerto (15%). Conclusão: Os resultados do \"Estudo de 3 modalidades de Tx em DM tipo1\" mostraram que em pacientes portadores de DM tipo 1 o transplante renal isolado realizado com doador vivo apresentou resultados superiores em relação às outras modalidades de transplante. Entretanto, em longo prazo, a sobrevida dos pacientes submetidos ao transplante renal com doador vivo não foi estatisticamente diferente do TSRP. Os resultados do \"Estudo do Tx em DM tipo 2 vs DM tipo1\" mostraram que o transplante renal com doador vivo é uma boa opção de terapia renal substitutiva para pacientes com DM tipo 2. Entretanto, os resultados observados nesta análise desencorajam a indicação de transplante renal com doador falecido para pacientes portadores de DM tipo 2, devendo ser indicado apenas em casos selecionados / Diabetes mellitus is the leading cause of chronic kidney disease (CKD) in several countries around the world. For diabetic patients with stage 5 CKD with an indication of renal replacement therapy, renal transplantation is a therapeutic modality with well-established technique and with excellent results. The simultaneous kidney-pancreas transplantation (SPK), a more recent modality of treatment, performed in a limited number of centers, presents additional positive results in metabolic control, quality of life, and chronic complications of diabetes mellitus (DM). However, it is associated with an increased risk of postoperative complications and a higher number of hospitalizations. Both renal and SPK transplantation are associated with better patient survival outcomes compared to dialysis. The choice of the best modality of transplantation for diabetic patients with CKD is not yet clear. The aim of this study was to analyze the results of different modalities of transplant for diabetic patients with CKD stage 5, performed in 3 Brazilian Transplant Centers. More specifically, the aim of this study was to analyze the patient and graft survival after 1, 5, and 8 years post-transplantation in type 1 DM patients submitted to SPK compared with diabetic patients submitted to isolated kidney transplant with living donor (DM1-LD) or deceased donor (DM1-DD) (Study of 3 Tx (transplant) modalities in type 1 DM). In addition, the aim of this study was also to evaluate the results of renal transplantation in type 2 DM performed with living donor (DM2-LD) or deceased donor (DM2-DD) compared with kidney transplantation in type 1 DM performed with living donor (DM2-LD) or deceased donor (DM2-DD) (Study of Tx in type 2 DM vs. type 1 DM). The transplants were performed in 3 Transplant Centers (Hospital Beneficência Portuguesa, Hospital do Rim, and Santa Casa de Porto Alegre). In the \"Study of 3 transplant modalities in type 1 DM\", 372 recipients were included, (262 SPK, 78 DM1-LD, and 32 DM1-DD). In the \"Study of Tx in type 2 DM vs. type 1 DM\", 254 transplants were included, 78 DM1-LD, 32 DM1-DD, 61 DM2-LD, 83 DM2-DD. Patient and graft survival distribution estimates were calculated using the Kaplan-Meier method in the 1, 5 and 8 years post-transplantation. In the \"Study of 3 transplant Tx modalities in type 1 DM\", the patient survival of DM1-LD recipients was significantly higher compared with the survival of DM1-DD and SPK at 1 year (98.7%, 87.5% and 83.2%, respectively; p < 0.05), and at 5 years post-transplantation (90.5%, 70% and 77%, respectively; p < 0.05). After 8 years, there was no significant difference between the survival of patients in group DM1-LD and SPK. The kidney graft survival was higher in DM1-LD, at 1 year, compared with survival of DM1-DD and SPK (96.2%, 84.4% and 80.8%, respectively; p < 0.05). After 5 and 8 years, the kidney graft survival was similar between the groups. There were 90 deaths during the study period and infection (50%) and cardiovascular disease (22%) were the major causes. Death with a functioning graft and chronic allograft nephropathy were the main causes of kidney graft loss. In the \"Study of Tx in type 2 DM vs. type 1 DM\", type 1 DM patients were younger compared to type 2 DM patients (median 37.5 and 55 years, respectively; p < 0.0001). Recipients of deceased donor remained longer time on dialysis before transplantation (median 36 months in DM1-DD, and 36 in DM2-DD) compared with patients transplanted with living donor (median 14 months in DM1-LD and 18 months in DM2-LD, p < 0.0001). In type 2 DM, patient survival at 1, 5 and 8 years in the group DM2-LD was 95.1%, 87.9%, and 81.8, respectively, significantly higher than patient survival in DM2-DD recipients (74.7, 59,4, and 48.5; respectively, p < 0.01). In type 1 DM, patient survival at 1, 5 and 8 years in the group DM1-LD was 98.7%, 90.5% and 82.1%, respectively, significantly higher than patient survival in DM1-DD recipients ( 87.5%, 70%, and 48.5%; respectively, p < 0.01). The comparison between patient survival with type 2 DM and type 1 DM undergoing kidney transplantation with the same type of donor, was not statistically different between the groups. Patient survival in group DM2-LD and DM1-LD was not different. Patient survival in the group DM2-DD was inferior to the group DM1-DD but without significant differences. In type 2 DM, kidney survival at 1, 5 and 8 years in the group DM2-LD was 91.8%, 81 2%, and 75.3%, respectively, significantly higher than patient survival in DM2-DD recipients (73.5%, 54.9%, and 44.3%, respectively, p < 0.01). In type 1 DM, kidney survival at 1, 5 and 8 years in the group DM1-LD was 96.1%, 80.8%, and 72.3%,, respectively, significantly higher than patient survival in DM1-DD recipients (84.4%, 66.8%, and 59.3%, respectively, p < 0.01) only in the first year. In these patients the kidney graft survival was superior in the group DM2-LD compared with DM2-DD. In type 1 DM patients kidney graft survival was 96.1%, 80.8% and 72.3% in patients DM1-LD; 84.4%, 66.8% and 59.3% in patients DM1-DD (p < 0.01); respectively. There were 52 deaths in the group of type 2 DM patients. Infection was the main cause of death in the group DM2-DD, and cardiovascular disease was the main cause in DM2-LD. There were 23 deaths in the group of type 1 DM patients and the main cause was infection in the group DM1-DD and cardiovascular disease in the group DM1-LD. The main cause of kidney graft loss was death with a functioning graft (74%), followed by chronic allograft nephropathy (15%). Patients in group DM2-LD showed good survival rates, particularly in the first year. Conclusion: The \"Study of 3 transplant modalities in type 1 DM\" showed better patient and graft survival with isolated kidney transplantation with living donor compared with others transplant modalities. However, at longer follow up (8 years), survival of patients undergoing living donor kidney transplantation was not statistically different to SPK. In the \"Study of Tx in type 2 DM vs. type 1 DM\", renal transplantation performed with living donor is a good option of renal replacement therapy for type 2 DM. The results observed in this analysis discourage the indication of kidney transplantation with deceased donor for patients with type 2 DM, which should be indicated in selected cases

Toute maladie rénale chronique (MRC), et ce quelle qu’en soit la cause, aboutit à une réduction néphronique, c’est-à-dire à une diminution du nombre d’unités fonctionnelles qui assurent la fonction rénale. Celle-ci se caractérise initialement par une croissance compensatrice des néphrons sains restants. Néanmoins, elle aboutit, dans certaines circonstances, à une détérioration secondaire de ces néphrons, responsable du déclin progressif de la fonction rénale. L’étude du modèle murin de réduction néphronique par néphrectomie subtotale (Nx) a permis de souligner le rôle des facteurs génétiques dans la susceptibilité de développer une MRC. En particulier, les souris FVB/N (FVB) développent une MRC précoce et sévère après Nx, à la différence des souris C57Bl/6 (B6) qui préservent l’intégrité de leur parenchyme rénal. Mon travail de thèse avait pour objectif d’identifier de nouvelles voies moléculaires impliquées dans les processus d’adaptation et de progression des MRC en réponse à la réduction néphronique. Le projet s’est articulé autour de deux axes menés en parallèle: - une approche « globale » fondée sur l’analyse temporelle et différentielle du transcriptome rénal des souches « sensibles » (FVB) et « résistantes » (B6) après Nx ; - une approche « candidate » centrée sur l’étude du rôle de YAP/TAZ au cours de la réduction néphronique. Dans un premier travail, l’analyse du profil d’expression transcriptomique rénal des souris « résistantes » et « sensibles » a permis d’ identifier une signature Interféron (IFN) de type I uniquement chez les souris FVB pendant la phase de compensation rénale. Cette signature était corrélée à une expression plus importante : (i) de marqueurs des cellules dendritiques plasmacytoïdes, connues pour leur capacité à produire rapidement et en grande quantité de l’IFN de type I ; et (ii) de marqueurs de nécroptose, qui représente une mort cellulaire immunogène associée à la libération par les cellules endommagées de signaux « dangers » pouvant induire l’activation des cellules immunitaires. Nous avons également établi un parallélisme entre cette signature IFN et des perturbations de la prolifération des cellules tubulaires. En effet, il existe 2 jours après la Nx, une activation de p21 dans les cellules tubulaires et un probable blocage des cellules en prolifération à la transition G1/S. Nos résultats suggèrent que ce blocage retentit sur le taux de prolifération des cellules tubulaires et sous-tend une tendance à l’hypertrophie rénale chez les souris FVB au cours de la phase de compensation rénale. Ce premier travail a permis de souligner le lien potentiel entre des processus cellulaires et moléculaires survenant précocement après Nx, au cours de la phase de compensation rénale, et l’évolution ultérieure vers la MRC chez les souris FVB. Dans un second travail découlant de l’étude temporelle et différentielle de l’expression de YAP dans le modèle de Nx chez les souris FVB et B6, nous avons montré que l’expression nucléaire de YAP dans les podocytes était maintenue voire augmentée chez les souris « résistantes » et diminuait fortement chez les souris « sensibles » avec une corrélation entre cette expression et la sévérité des lésions glomérulaires. L’invalidation spécifique dans les podocytes de YAP, ou de son paralogue TAZ, chez des souris initialement « résistantes » a permis de mieux préciser leur rôle respectif dans l’adaptation des podocytes à la réduction néphronique. L’inactivation de YAP s’associe à : (i) l’apparition de lésions de hyalinose segmentaire et focale et de glomérulosclérose; (ii) une augmentation de l’apoptose glomérulaire ; (iii) une altération de l’architecture du cytosquelette des podocytes ; et (iv) une raréfaction podocytaire responsable d’une albuminurie et d’une détérioration de la fonction rénale. L’invalidation de TAZ n’induit pas de phénotype glomérulaire. A la différence de TAZ, YAP joue donc un rôle crucial dans l’adaptation podocytaire à la réduction néphronique. / Chronic kidney disease (CKD), irrespectively of the underlying cause, usually leads to nephron reduction, which is defined by a decrease in the number of the renal functional units. This is first characterized by a compensatory growth of the remaining nephrons, which in some circumstances, may result in the progressive deterioration of the initially healthy nephrons. The study of subtotal nephrectomy (Nx), a murine model of nephron reduction, has outlined the role of genetic factors in the susceptibility of developing CKD after nephron reduction. In particular, FVB/N mice (FVB) develop early and severe CKD after Nx, contrary to C57Bl/6 (B6) mice that are characterized by a preserved renal parenchyma. My work aimed at identifying new molecular pathways involved in the adaptation and progression processes in response to nephron reduction. The project was articulated around two main axes: - a "global" approach with the temporal and differential analysis of the renal transcriptome of "sensitive" (FVB) and "resistant" strains (B6) after Nx ; - a "candidate" approach centered on the study of the role of YAP/TAZ during nephron reduction. In the first work, the analysis of the renal transcriptomic expression profile of "resistant" and "sensitive" mice allowed to identify a type I interferon (IFN) signature only in the FVB mice during the renal compensation phase. This signature was correlated with a more important expression of markers of : (i) plasmacytoid dendritic cells, known for their ability to rapidly produce large amount of type I IFN; and (ii) necroptosis, an immunogenic cell death associated with the release of "danger" signals by the damaged cells that may induce activation of the immune cells. We have also established a parallelism between this IFN signature and alterations of tubular cells proliferation. Indeed, 2 days after Nx, we observed an activation of p21 in the tubular cells associated with a likely G1/S blockade of proliferating cells. Our results suggest that this cell cycle arrest affects the proliferation rate of tubular cells and underlies a trend for renal hypertrophy in FVB mice during the renal compensation phase. This first work pointed to a potential link between cellular and molecular processes occurring early after Nx, during the compensation phase, and the subsequent progression towards CKD in FVB mice. In a second work investigating the temporal and differential expression of YAP in the Nx model in FVB and B6 mice, we showed that the nuclear expression of YAP in podocytes was maintained and even increased in the “resistant” mice, and decreased significantly in "sensitive" mice with a correlation between this expression and the severity of glomerular lesions. The specific knockdown of YAP, or of its paralogous TAZ, in the podocytes of initially "resistant" mice allowed to better determine their respective role in the adaptation of these cells to nephron reduction. YAP podocyte-specific inactivation is associated with: (i) the development of focal and segmental glomerulosclerosis lesions; (ii) an increase of glomerular apoptosis; (iii) an alteration of the architecture of podocytes cytoskeleton; and (iv) podocyte rarefaction responsible for albuminuria and deterioration of renal function. Surprisingly, TAZ podocyte-specific inactivation was not associated with glomerular lesions. Contrary to TAZ, YAP plays a crucial role in podocyte adaptation to nephron reduction.

INTRODUÇÃO: O hiperparatireoidismo secundário (HPTS) é uma complicação da doença renal crônica que compromete a integridade do esqueleto. Pacientes com HPS submetidos à paratireoidectomia (PTX) passam de uma condição de níveis séricos de paratormônio (PTH) muito elevados para outra, onde esses níveis hormonais caem drasticamente. Os efeitos da PTX no tecido ósseo são mal compreendidos, especialmente no que se refere às proteínas expressas por osteócitos, como o fator de crescimento de fibroblastos 23 (FGF23), dentin matrix protein 1 (DMP-1), fosfoglicoproteína de matriz extracelular (MEPE), esclerostina, Fator nuclear Kappa beta ligante (RANKL) e osteoprotegerina (OPG), que regulam a remodelação e a mineralização óssea. OBJETIVOS: Caracterizar a expressão óssea dessas proteínas por imuno-histoquímica e estabelecer relações com os dados da histomorfometria do tecido ósseo em pacientes com HPS, antes e após a PTX. MÉTODOS: Estudamos biópsias ósseas obtidas de um banco de biópsias de 23 pacientes com DRC e HPTS, que foram realizadas antes e 12 meses após a PTX. RESULTADOS: A avaliação dos parâmetros histomorfométricos demonstrou uma melhora da microarquitetura óssea, porém com um maior retardo em sua mineralização após a PTX. A análise da expressão das proteínas osteocíticas revelou um aumento significativo na expressão da esclerostina e da OPG e uma diminuição da relação RANKL/OPG após a PTX, sugerindo a participação dessas proteínas na melhora das lesões ósseas decorrentes do HPTS. Observamos um aumento significativo na expressão da OPG no grupo de pacientes que evoluiu com defeito de mineralização somente após a cirurgia, sugerindo a participação dessa proteína no retardo de mineralização óssea desses pacientes. A expressão das proteínas osteocíticas que participam da formação e mineralização óssea apresentou correlação com parâmetros envolvidos na remodelação óssea. CONCLUSÕES: Mudanças significativas na expressão óssea de proteínas osteocíticas que podem potencialmente regular a remodelação e a mineralização óssea foram observadas após a PTX / INTRODUCTION: Secondary hyperparathyroidism (SHPT) is a complication of chronic kidney disease that compromises skeletal integrity. Patients with SHPT undergoing parathyroidectomy (PTX) go from a very high serum parathyroid hormone (PTH) condition to another, where these hormonal levels dramatically fall. The effects of PTX on bone tissue are poorly understood, especially as regards proteins expressed by osteocytes, such as fibroblast growth factor 23 (FGF23), dentin matrix protein 1 (DMP-1), extracellular matrix phosphoglycoprotein (MEPE), sclerostin, Kappa beta ligand nuclear factor (RANKL) and osteoprotegerin (OPG), which regulate bone remodeling and mineralization. OBJECTIVES: Characterize bone expression of these proteins by immunohistochemistry and establish relations with bone tissue histomorphometry data in SHPT patients, before and after PTX. METHODS: We studied bone biopsies obtained from a biopsy database of 23 patients with CKD and SHPT, which were performed before PTX and 12 months after PTX. RESULTS: Evaluation of histomorphometric parameters showed improvement of bone microarchitecture, but with longer delay in mineralization after PTX. Analysis of osteocyte protein expression revealed significant increase in sclerostin and OPG expression and decrease in RANKL/OPG ratio after PTX, suggesting participation of these proteins in improvement of bone lesions due to SHPT. We observed significant increase in OPG expression in the group of patients who evolved with mineralization defect only after surgery, suggesting participation of this protein in bone mineralization delay of these patients. Expression of osteocyte proteins that participate in bone formation and mineralization correlated with parameters involved in bone remodeling. CONCLUSIONS: Significant changes in bone expression of osteocyte proteins that can potentially regulate bone remodeling and mineralization were observed after PTX

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INTRODUÇÃO: O hiperparatireoidismo secundário (HPTS) é uma complicação da doença renal crônica que compromete a integridade do esqueleto. Pacientes com HPS submetidos à paratireoidectomia (PTX) passam de uma condição de níveis séricos de paratormônio (PTH) muito elevados para outra, onde esses níveis hormonais caem drasticamente. Os efeitos da PTX no tecido ósseo são mal compreendidos, especialmente no que se refere às proteínas expressas por osteócitos, como o fator de crescimento de fibroblastos 23 (FGF23), dentin matrix protein 1 (DMP-1), fosfoglicoproteína de matriz extracelular (MEPE), esclerostina, Fator nuclear Kappa beta ligante (RANKL) e osteoprotegerina (OPG), que regulam a remodelação e a mineralização óssea. OBJETIVOS: Caracterizar a expressão óssea dessas proteínas por imuno-histoquímica e estabelecer relações com os dados da histomorfometria do tecido ósseo em pacientes com HPS, antes e após a PTX. MÉTODOS: Estudamos biópsias ósseas obtidas de um banco de biópsias de 23 pacientes com DRC e HPTS, que foram realizadas antes e 12 meses após a PTX. RESULTADOS: A avaliação dos parâmetros histomorfométricos demonstrou uma melhora da microarquitetura óssea, porém com um maior retardo em sua mineralização após a PTX. A análise da expressão das proteínas osteocíticas revelou um aumento significativo na expressão da esclerostina e da OPG e uma diminuição da relação RANKL/OPG após a PTX, sugerindo a participação dessas proteínas na melhora das lesões ósseas decorrentes do HPTS. Observamos um aumento significativo na expressão da OPG no grupo de pacientes que evoluiu com defeito de mineralização somente após a cirurgia, sugerindo a participação dessa proteína no retardo de mineralização óssea desses pacientes. A expressão das proteínas osteocíticas que participam da formação e mineralização óssea apresentou correlação com parâmetros envolvidos na remodelação óssea. CONCLUSÕES: Mudanças significativas na expressão óssea de proteínas osteocíticas que podem potencialmente regular a remodelação e a mineralização óssea foram observadas após a PTX / INTRODUCTION: Secondary hyperparathyroidism (SHPT) is a complication of chronic kidney disease that compromises skeletal integrity. Patients with SHPT undergoing parathyroidectomy (PTX) go from a very high serum parathyroid hormone (PTH) condition to another, where these hormonal levels dramatically fall. The effects of PTX on bone tissue are poorly understood, especially as regards proteins expressed by osteocytes, such as fibroblast growth factor 23 (FGF23), dentin matrix protein 1 (DMP-1), extracellular matrix phosphoglycoprotein (MEPE), sclerostin, Kappa beta ligand nuclear factor (RANKL) and osteoprotegerin (OPG), which regulate bone remodeling and mineralization. OBJECTIVES: Characterize bone expression of these proteins by immunohistochemistry and establish relations with bone tissue histomorphometry data in SHPT patients, before and after PTX. METHODS: We studied bone biopsies obtained from a biopsy database of 23 patients with CKD and SHPT, which were performed before PTX and 12 months after PTX. RESULTS: Evaluation of histomorphometric parameters showed improvement of bone microarchitecture, but with longer delay in mineralization after PTX. Analysis of osteocyte protein expression revealed significant increase in sclerostin and OPG expression and decrease in RANKL/OPG ratio after PTX, suggesting participation of these proteins in improvement of bone lesions due to SHPT. We observed significant increase in OPG expression in the group of patients who evolved with mineralization defect only after surgery, suggesting participation of this protein in bone mineralization delay of these patients. Expression of osteocyte proteins that participate in bone formation and mineralization correlated with parameters involved in bone remodeling. CONCLUSIONS: Significant changes in bone expression of osteocyte proteins that can potentially regulate bone remodeling and mineralization were observed after PTX

O diabetes mellitus (DM) é a principal causa de doença renal crônica (DRC) em vários países do mundo. Para pacientes diabéticos com DRC estágio 5 e indicação da terapia renal substitutiva, o transplante (Tx) renal representa uma modalidade terapêutica com técnica bem estabelecida e com excelentes resultados. O transplante simultâneo de rim-pâncreas (TSRP), uma alternativa mais recente praticada em um número mais restrito de centros, apresenta resultados positivos adicionais no controle metabólico, na qualidade de vida e nas complicações crônicas do diabetes. Entretanto, está associado a um risco maior de complicações pós-operatórias e maior número de internações. Tanto o transplante renal quanto o TSRP estão associados a melhor sobrevida do paciente em relação à diálise. A escolha da melhor modalidade de transplante para o paciente diabético com DRC ainda não está clara. O objetivo deste estudo foi analisar os resultados de diferentes modalidades de transplante em pacientes diabéticos com DRC estágio 5, realizados em 3 Centros Brasileiros de Transplante. Assim, analisar a sobrevida do paciente e do enxerto renal após 1, 5 e 8 anos em pacientes DM tipo 1 submetidos a TSRP comparados com transplante renal isolado com doador vivo (DM1-DV) ou transplante de renal isolado com doador falecido (DM1-DF) (Estudo de 3 modalidades de Tx em DM tipo1). Além disso, avaliar em pacientes DM tipo 2, os resultados do transplante renal realizado com doador vivo (DM2-DV) ou doador falecido (DM2-DF) comparados com pacientes DM tipo 1 submetidos ao transplante renal com doador vivo (DM1-DV) ou doador falecido (DM1-DF) (Estudo do Tx em DM tipo 2 vs DM tipo1). Os transplantes foram realizados em 3 Centros de Transplante (Hospital Beneficência Portuguesa, Hospital do Rim e Santa Casa de Porto Alegre). No \"Estudo de 3 modalidades de Tx em DM tipo 1\", foram incluídos 372 transplantes, sendo 262 TSRP, 78 DM1-DV e 32 DM1-DF. No \"Estudo do Tx em DM tipo 2 vs DM tipo 1\", foram incluídos 254 transplantes, sendo 78 DM1-DV, 32 DM1-DF, 61 DM2-DV, 83 DM2-DF. As curvas de sobrevida do paciente e do enxerto renal (Kaplan-Meyer) foram calculadas 1, 5 e 8 anos após o transplante. No \"Estudo de 3 modalidades de Tx em DM tipo 1\", a sobrevida do paciente de receptores de DM1-DV foi significativamente superior comparada com a sobrevida dos receptores de DM1-DF e TSRP no 1º ano (98,7%, 87,5% e 83,2%, respectivamente; p < 0,05) e no 5º ano pós-Tx (90,5%, 70% e 77%, respectivamente; p < 0,05). Não foi observada diferença entre a sobrevida dos pacientes do grupo DM1-DV e TSRP em 8 anos. A sobrevida do enxerto renal foi superior nos receptores DM1-DV no 1º ano pós-Tx, quando comparada com a sobrevida dos receptores DM1-DF e TSRP (96,1%, 84,4% e 80,2%, respectivamente; p < 0,05). Após 5 e 8 anos, a sobrevida do enxerto renal foi semelhante entre os grupos. Ocorreram 90 óbitos durante o período de estudo sendo as principais causas, a infecção (50%) e doença cardiovascular (22%). Óbito com enxerto funcionante e nefropatia crônica do enxerto foram as principais causas de perda do enxerto renal. No \"Estudo do Tx em DM tipo 2 vs DM tipo 1\", como esperado, os pacientes DM tipo 1 eram mais jovens em relação aos pacientes DM tipo 2 (mediana 37,5 e 55 anos, respectivamente; p < 0,0001). Os pacientes transplantados com doador falecido permaneceram maior tempo em tratamento dialítico pré-transplante (mediana 36 meses em DM1-DF e 36 meses em DM2-DF) comparados com pacientes transplantados com doador vivo (mediana 14 meses em DM1-DV e 18 meses em DM2-DV; p < 0,0001). Em pacientes com DM tipo 2, a sobrevida do paciente em 1, 5 e 8 anos nos pacientes DM2-DV foi 95,1%, 87,9% e 81,8%, respectivamente, significativamente maior do que nos pacientes DM2-DF (74,7%, 59,4% e 48,5%, respectivamente; p < 0,01). Em pacientes com DM tipo 1, a sobrevida do paciente em 1, 5 e 8 anos foi 98,7%, 90,5% e 82,1%, respectivamente, significativamente maior do que nos pacientes DM1-DV que nos pacientes DM1-DF (87,5%, 70% e 66,3%, respectivamente; p < 0,01). Comparando-se a sobrevida dos pacientes DM tipo 2 em relação aos DM tipo 1 submetidos a transplante com um mesmo tipo de doador, não foi observado diferença estatisticamente significante. Pacientes do grupo DM2-DV e pacientes DM1-DV apresentaram sobrevidas semelhantes. A sobrevida dos pacientes DM2-DF encontrada foi inferior em relação aos pacientes DM1-DF, porém sem diferença estatística. Em pacientes com DM tipo 2, a sobrevida do enxerto renal em 1, 5 e 8 anos nos pacientes DM2-DV foi 91,8%, 81,2% e 75,3%, respectivamente, significativamente maior do que nos pacientes DM2-DF (73,5%, 54,9% e 44.3%, respectivamente; p < 0,01). Em pacientes com DM tipo 1, a sobrevida do enxerto renal em 1, 5 e 8 anos nos pacientes DM1-DV foi 96,1%, 80,8% e 72,3%, respectivamente, significativamente maior do que nos pacientes DM1-DF (84,4%, 66,8% e 59,3%, respectivamente; p < 0,01) apenas no primeiro ano. Ocorreram 52 óbitos em pacientes DM tipo 2 sendo a infecção principal causa de óbito nos pacientes DM2-DF e a doença cardiovascular a principal causa de óbito nos DM2-DV. Ocorreram 23 óbitos no grupo de pacientes DM tipo 1 e a principal causa foi infecção nos pacientes DM1-DF e a doença cardiovascular nos DM1-DV. A principal causa de perda do enxerto renal foi óbito com enxerto funcionante (74%), seguido pela nefropatia crônica do enxerto (15%). Conclusão: Os resultados do \"Estudo de 3 modalidades de Tx em DM tipo1\" mostraram que em pacientes portadores de DM tipo 1 o transplante renal isolado realizado com doador vivo apresentou resultados superiores em relação às outras modalidades de transplante. Entretanto, em longo prazo, a sobrevida dos pacientes submetidos ao transplante renal com doador vivo não foi estatisticamente diferente do TSRP. Os resultados do \"Estudo do Tx em DM tipo 2 vs DM tipo1\" mostraram que o transplante renal com doador vivo é uma boa opção de terapia renal substitutiva para pacientes com DM tipo 2. Entretanto, os resultados observados nesta análise desencorajam a indicação de transplante renal com doador falecido para pacientes portadores de DM tipo 2, devendo ser indicado apenas em casos selecionados / Diabetes mellitus is the leading cause of chronic kidney disease (CKD) in several countries around the world. For diabetic patients with stage 5 CKD with an indication of renal replacement therapy, renal transplantation is a therapeutic modality with well-established technique and with excellent results. The simultaneous kidney-pancreas transplantation (SPK), a more recent modality of treatment, performed in a limited number of centers, presents additional positive results in metabolic control, quality of life, and chronic complications of diabetes mellitus (DM). However, it is associated with an increased risk of postoperative complications and a higher number of hospitalizations. Both renal and SPK transplantation are associated with better patient survival outcomes compared to dialysis. The choice of the best modality of transplantation for diabetic patients with CKD is not yet clear. The aim of this study was to analyze the results of different modalities of transplant for diabetic patients with CKD stage 5, performed in 3 Brazilian Transplant Centers. More specifically, the aim of this study was to analyze the patient and graft survival after 1, 5, and 8 years post-transplantation in type 1 DM patients submitted to SPK compared with diabetic patients submitted to isolated kidney transplant with living donor (DM1-LD) or deceased donor (DM1-DD) (Study of 3 Tx (transplant) modalities in type 1 DM). In addition, the aim of this study was also to evaluate the results of renal transplantation in type 2 DM performed with living donor (DM2-LD) or deceased donor (DM2-DD) compared with kidney transplantation in type 1 DM performed with living donor (DM2-LD) or deceased donor (DM2-DD) (Study of Tx in type 2 DM vs. type 1 DM). The transplants were performed in 3 Transplant Centers (Hospital Beneficência Portuguesa, Hospital do Rim, and Santa Casa de Porto Alegre). In the \"Study of 3 transplant modalities in type 1 DM\", 372 recipients were included, (262 SPK, 78 DM1-LD, and 32 DM1-DD). In the \"Study of Tx in type 2 DM vs. type 1 DM\", 254 transplants were included, 78 DM1-LD, 32 DM1-DD, 61 DM2-LD, 83 DM2-DD. Patient and graft survival distribution estimates were calculated using the Kaplan-Meier method in the 1, 5 and 8 years post-transplantation. In the \"Study of 3 transplant Tx modalities in type 1 DM\", the patient survival of DM1-LD recipients was significantly higher compared with the survival of DM1-DD and SPK at 1 year (98.7%, 87.5% and 83.2%, respectively; p < 0.05), and at 5 years post-transplantation (90.5%, 70% and 77%, respectively; p < 0.05). After 8 years, there was no significant difference between the survival of patients in group DM1-LD and SPK. The kidney graft survival was higher in DM1-LD, at 1 year, compared with survival of DM1-DD and SPK (96.2%, 84.4% and 80.8%, respectively; p < 0.05). After 5 and 8 years, the kidney graft survival was similar between the groups. There were 90 deaths during the study period and infection (50%) and cardiovascular disease (22%) were the major causes. Death with a functioning graft and chronic allograft nephropathy were the main causes of kidney graft loss. In the \"Study of Tx in type 2 DM vs. type 1 DM\", type 1 DM patients were younger compared to type 2 DM patients (median 37.5 and 55 years, respectively; p < 0.0001). Recipients of deceased donor remained longer time on dialysis before transplantation (median 36 months in DM1-DD, and 36 in DM2-DD) compared with patients transplanted with living donor (median 14 months in DM1-LD and 18 months in DM2-LD, p < 0.0001). In type 2 DM, patient survival at 1, 5 and 8 years in the group DM2-LD was 95.1%, 87.9%, and 81.8, respectively, significantly higher than patient survival in DM2-DD recipients (74.7, 59,4, and 48.5; respectively, p < 0.01). In type 1 DM, patient survival at 1, 5 and 8 years in the group DM1-LD was 98.7%, 90.5% and 82.1%, respectively, significantly higher than patient survival in DM1-DD recipients ( 87.5%, 70%, and 48.5%; respectively, p < 0.01). The comparison between patient survival with type 2 DM and type 1 DM undergoing kidney transplantation with the same type of donor, was not statistically different between the groups. Patient survival in group DM2-LD and DM1-LD was not different. Patient survival in the group DM2-DD was inferior to the group DM1-DD but without significant differences. In type 2 DM, kidney survival at 1, 5 and 8 years in the group DM2-LD was 91.8%, 81 2%, and 75.3%, respectively, significantly higher than patient survival in DM2-DD recipients (73.5%, 54.9%, and 44.3%, respectively, p < 0.01). In type 1 DM, kidney survival at 1, 5 and 8 years in the group DM1-LD was 96.1%, 80.8%, and 72.3%,, respectively, significantly higher than patient survival in DM1-DD recipients (84.4%, 66.8%, and 59.3%, respectively, p < 0.01) only in the first year. In these patients the kidney graft survival was superior in the group DM2-LD compared with DM2-DD. In type 1 DM patients kidney graft survival was 96.1%, 80.8% and 72.3% in patients DM1-LD; 84.4%, 66.8% and 59.3% in patients DM1-DD (p < 0.01); respectively. There were 52 deaths in the group of type 2 DM patients. Infection was the main cause of death in the group DM2-DD, and cardiovascular disease was the main cause in DM2-LD. There were 23 deaths in the group of type 1 DM patients and the main cause was infection in the group DM1-DD and cardiovascular disease in the group DM1-LD. The main cause of kidney graft loss was death with a functioning graft (74%), followed by chronic allograft nephropathy (15%). Patients in group DM2-LD showed good survival rates, particularly in the first year. Conclusion: The \"Study of 3 transplant modalities in type 1 DM\" showed better patient and graft survival with isolated kidney transplantation with living donor compared with others transplant modalities. However, at longer follow up (8 years), survival of patients undergoing living donor kidney transplantation was not statistically different to SPK. In the \"Study of Tx in type 2 DM vs. type 1 DM\", renal transplantation performed with living donor is a good option of renal replacement therapy for type 2 DM. The results observed in this analysis discourage the indication of kidney transplantation with deceased donor for patients with type 2 DM, which should be indicated in selected cases

Aims: 1. Determination of AGEs (Advanced Glycation End products) in patients with various types of nephropathy. 2. Association AGEs with nutritional parameters and anemia. 3. Influence of renal parameters on sRAGE (soluble form of Receptor for Advanced Glycation End products) levels. 4. Technics and proceeding methods of the podocytes cultivation. 5. Determination of urine podocytes. Methods: We determined fluorescent AGEs by spectrofluorometry, sRAGE by Enzyme-Linked ImmunoSorbent Assay (ELISA). Podocytes were passaged and identified immunocytochemically. Podocytes in urine were specified by flow cytometry method. Results: 1. We did not find significant differences in AGEs serum levels among various types of nephropathy, even though the pathogenesis differs. 2. The albumin and prealbumin levels positively and haemoglobin levels negatively correlate with AGEs in patients with CKD grade 1-5, without necessity of dialysis. 3. Serum sRAGE levels are increased in patients with decreased renal function independently on the course of renal disease. 4. We implemented the methods and technics of podocyte cultivation. 5. Urine podocytes observation and confirmation that podocyturia relates to disease activity. Conclusion: We confirmed that AGEs serum levels depend more on renal function than the type of...

Renal tubules represent an intercellular unit and function as a syncytium. When acute tubular necrosis was first visualized to occur through a process of synchronized regulated necrosis (SRN) in handpicked primary renal tubules, it became obvious that SRN actually promotes nephron loss. This realization adds to our current understanding of acute kidney injury (AKI)-chronic kidney disease (CKD) transition and argues for the prevention of AKI episodes to prevent CKD progression. Because SRN is triggered by necroptosis and executed by ferroptosis, 2 recently identified signaling pathways of regulated necrosis, a combination therapy employing necrostatins and ferrostatins may be beneficial for protection against nephron loss. Clinical trials in AKI and during the process of kidney transplantation are now required to prevent SRN. Additionally, necrotic cell death drives autoimmunity and necroinflammation and therefore represents a therapeutic target even for the prevention of antibody-mediated rejection of allografts years after the transplantation process.