Hypertension artérielle résistante et maladie rénale chronique : Déterminants et risques associésL’hypertension résistante, définie par une pression artérielle au-dessus de la cible en dépit de la prise de trois antihypertenseurs à dose optimale dont un diurétique, est fréquemment associée à la maladie rénale chronique (MRC). Sa prévalence, ses déterminants et l’impact potentiel de la MRC sur son pronostic à long terme sont mal connus, notamment chez le sujet âgé. Dans l’étude des 3 cités, incluant 4262 personnes de plus de 65 ans traitées pour hypertension, la prévalence de l’hypertension apparemment résistante (HTAR) - la notion de traitement à dose optimale étant inconnue - était de 11,8% vs 5,2% chez ceux avec vs sans MRC (définie par une fonction rénale < 60 mL/min/1.73 m2). Nous avons montré que l’apparition d’une HTAR était plus fortement liée à la rapidité du déclin annuel de la fonction rénale qu’à son niveau, indépendamment des autres facteurs de risque : obésité, diabète, sexe masculin, antécédent cardiovasculaire. Comparé au groupe de référence (avec hypertension contrôlée et sans MRC), les personnes avec une HTAR et une MRC n’avaient pas de risque significativement plus élevé de mortalité toute cause, mais avaient deux fois plus de risque d’accident vasculaire cérébral (AVC), létal ou non, et de récurrence d’un AVC ou d’un événement coronaire, et trois fois plus de décès coronaire. Cependant, l’’hypothèse d’un effet aggravant de la MRC sur le pronostic de l’HTAR n’a pas été confirmé (interaction non significative).Dans la cohorte CKD-REIN, incluant plus de 3000 patients avec une MRC modérée ou avancée suivis en néphrologie (âge moyen, 70 ans, 60% d’hommes), nos résultats préliminaires montrent une prévalence élevée d’HTAR, 36,7%, et plusieurs facteurs de risque potentiellement modifiables : adhérence médiocre au traitement, absence de diurétique, consommation de sel en excès, obésité.Dans l’ensemble, ces travaux montrent l’importance de la MRC dans le développement de l’HTAR et des risques cardiovasculaires associés, et suggère des moyens de prévention au-delà des traitements médicamenteux. / Resistant hypertension and chronic kidney disease: Determinants and outcomesResistant hypertension defined as blood pressure above goal despite simultaneous use of 3 antihypertensive classes at optimal doses including a diuretic, is commonly associated with chronic kidney disease (CKD). Resistant hypertension prevalence and determinants, and the impact of CKD on its long term outcomes are poorly known, particularly in the elderly population.In the 3 Cities cohort, including 4262 community-dwelling elderly individuals, aged 65 years or older treated for hypertension, the prevalence of apparent treatment resistant hypertension (aTRH) – because of lack of information on optimal treatment dose – was 11.8% vs 5.2% in those with vs without CKD (defined as estimated glomerular filtration rate < 60 mL/min/1.73 m2). We showed that new-onset aTRH was more strongly related to the speed of kidney function decline than kidney function level itself, independent of other risk factors: male sex, obesity, diabetes, and history of cardiovascular disease. Compared to the reference group (with controlled hypertension and no CKD), participants with aTRH and CKD had no significantly higher risk of all-cause mortality, but had a risk of fatal or non-fatal stroke and of recurrent stroke or coronary events more than twice as high, and of coronary death more than three times higher. However, the hypothesis that CKD may worsen the prognosis of aTRH was not confirmed (no significant interaction).In the CKDREIN cohort, which included more than 3000 nephrology outpatients with moderate or severe CKD (mean age, 70 years, 60% of men), our preliminary results showed a high prevalence of aTRH, 36,7% and several potentially modifiable risk factors : poor treatment adherence, lack of diuretic use, excess salt intake and obesity.Overall, this work shows the importance of CKD in the development of aTRH and associated cardiovascular outcomes, and suggests means for prevention beyond drug therapy.

La biosurveillance humaine permet aujourd’hui d’évaluer notre exposition aux produits chimiques par la mesure soit des substances elles-mêmes, soit de leurs métabolites ou marqueurs d'effets sur la santé, à partir des fluides corporels ou des tissus. Les informations recueillies dans le cadre d’enquêtes épidémiologiques renseignent sur l'exposition humaine et constituent des bases précieuses dans la recherche des relations exposition-réponse chez les humains. Les travaux de cette thèse s’inscrivent dans le cadre de l’enquête transversale IMePoGe conduite entre 2008-2010 dans la région Nord–Pas-de-Calais (au nord de la France), incluant 2000 résidents adultes âgés de 20 à 59 ans, et visant à quantifier les niveaux d’imprégnation de la population à 14 métaux et métalloïdes (aluminium, antimoine, arsenic total, béryllium, cadmium, cobalt, chrome, mercure, manganèse, nickel, plomb, thallium, vanadium, zinc) choisis pour leurs effets toxiques et la fréquence de l’exposition professionnelle et environnementale. Les objectifs spécifiques de cette thèse étaient, tout en portant une attention particulière au plomb et au cadmium, deux métaux néphrotoxiques connus dans la littérature : i) d’établir la distribution de l’imprégnation aux métaux et métalloïdes dans la population du Nord de la France et de comparer le niveau régional d’imprégnation avec les données nationales et internationales ; ii) d’identifier les facteurs majeurs de variation de l’imprégnation et les sources d’exposition au plomb et au cadmium dans la population générale ; iii) d’étudier la relation entre la variation du débit de filtration glomérulaire et les niveaux d’imprégnation aux métaux. Globalement, les concentrations sanguines et urinaires de la plupart des métaux et métalloïdes étaient plus élevées que celles rapportées dans l’enquête nationale nutrition santé conduite sur la même période dans la population française, à l’exception du vanadium urinaire et du plomb sanguin. La plombémie moyenne régionale (moyenne géométrique) était de 18,8 μg/L. De nombreuses sources d’exposition au plomb existaient dans la population et étaient à la fois d’origine professionnelle, environnementale et alimentaire. Pour ce qui est du cadmium, le tabagisme se présentait comme la principale source d’exposition récente ou chronique au métal : la cadmiémie moyenne, reflet de l’exposition récente, était de 0,39 μg/L et passait de 0,26 μg/L chez les non-fumeurs à 0,84 μg/L chez les fumeurs ; la cadmiurie moyenne, reflet de l’exposition chronique, était de 0,37 μg/L (0,33 μg/g créatinine) et passait de 0,33 μg/L (0,29 μg/g créatinine) chez les non-fumeurs à 0,46 μg/L (0.37 μg/g créatinine) chez les fumeurs. Enfin, dans le cadre de l’étude de la relation entre l’imprégnation aux métaux et le débit de filtration glomérulaire, notre étude a montré que la prise en compte de la co-exposition à d’autres métaux et métalloïdes potentiellement néphrotoxiques bouleversait considérablement les associations antérieures jusqu’ici rapportées spécifiquement avec le plomb et le cadmium, dans le cadre de faibles niveaux d’imprégnation en population générale. / Human Biomonitoring allows us to evaluate our exposure to chemicals by measuring substances themselves or their metabolites or markers of health effects, from body fluids or tissues. The information collected through epidemiological surveys provide information on human exposure and are valuable databases in the research of exposure-response relationships in humans. This thesis is part of the cross-sectional IMePoGe survey conducted between 2008-2010 in the Nord–Pas-de-Calais region (in northern France), including 2,000 adult residents aged 20 to 59 years old, and aimed to quantify the impregnation levels of the population to 14 metals and metalloids (aluminum, antimony, total arsenic, beryllium, cadmium, cobalt, chromium, mercury, manganese, nickel, lead, thallium, vanadium, zinc) chosen for their toxic effects and the frequency of occupational and environmental exposure. The specific objectives of this thesis were, which a special interest for lead and cadmium, two nephrotoxic metals known in the literature: i) to establish the distribution of impregnation metals into the northern population of France and compare the exposure regional level to metals and metalloids with the national and international data; ii) to identify the major factors of variation of the impregnation and the sources of exposure to lead and cadmium in the general population; iii) to study the relationship between the change in glomerular filtration rate and the impregnation levels to metals. Overall, blood and urinary concentrations of most metals and metalloids were higher than those found in the national nutritional health survey conducted during the same period in the French population, with the exception of urinary vanadium and blood lead. The regional mean of blood lead level (geometric mean) was 18.8 μg/L. Several sources of lead exposure existed in the population and were link to the occupational, environmental and consumption parameters. Regarding cadmium, smoking was the main source of recent or chronic exposure to metal: the geometric mean of blood cadmium, reflecting a recent exposure, was 0.39 μg/L and increased from 0.26 μg/L in non-smokers to 0.84 μg/L in smokers; the geometric mean of urinary cadmium, reflecting the chronic exposure, was 0.37 μg/L (0.33 μg/g creatinine) and increased from 0.33 μg/L (0.29 μg/g creatinine) in non-smokers to 0.46 μg/L (0.37 μg/g creatinine) in smokers. Finally, as part of the study of the relationship between the metal levels and the glomerular filtration rate, our study showed that taking into account the multiple exposure to the other potentially nephrotoxic metals and metalloids upset considerably the previous associations specifically reported with lead and cadmium, in the context of low levels exposure in the general population.

La administración de hierro intravenoso a pacientes con deficiencia de hierro mejora la hemoglobina preoperatoria y el riesgo de transfusión en cirugías de alto riesgo hemorrágico y reduce la morbimortalidad en la insuficiencia cardíaca sintomática. En la cirugía cardíaca, el efecto de dicho tratamiento no ha sido bien analizado, a pesar de que son frecuentes tanto la deficiencia de hierro como la insuficiencia cardíaca sintomática y que la anemia preoperatoria condiciona mayor riesgo de transfusión y de forma sinérgica a esta una mayor morbimortalidad. En el Hospital Universitario del Vinalopó la cirugía cardíaca consumía más del 20% de los concentrados de hematíes transfundidos antes de la incorporación a la práctica clínica de la optimización prequirúrgica con hierro intravenoso a los pacientes con deficiencia de hierro. Además, la cirugía de sustitución valvular era la modalidad quirúrgica que más componentes sanguíneos requería, a pesar de ser menos frecuente que la cirugía de bypass coronario. Se diseñó un estudio observacional analítico retrospectivo con el objetivo de analizar el efecto que tuvo la incorporación a la práctica clínica en 2012, del tratamiento preoperatorio de la deficiencia de hierro en candidatos a sustitución valvular cardíaca electiva, tras obtener la aprobación de la Comisión de Investigación del Hospital Universitario del Vinalopó. Se analizaron las 624 sustituciones valvulares electivas consecutivas, que se realizaron a 620 pacientes desde septiembre de 2010 a diciembre de 2014. De estos pacientes intervenidos electivamente, el 62,66% presentaron deficiencia de hierro (36,0% absoluta), el 23,48% tenían anemia basal y un 83.1% insuficiencia cardíaca con clase funcional de la “New York Heart Association” (NYHA) II-IV. Se adoptaron como criterios de inclusión para el estudio de la efectividad del tratamiento de la deficiencia de hierro: pacientes >18 años, sustitución valvular electiva, deficiencia de hierro (ferritina <100μg/L o [100-299μg/L] con índice de saturación de transferrina <20%). Como criterios de exclusión se consideraron: la ausencia de estudio de anemia y perfil férrico en la visita basal en la que se estableció la indicación de la cirugía (no determinación de Hemoglobina, ferritina o saturación de la transferrina), la ausencia de determinación de Hemoglobina en las 24 horas anteriores a la cirugía, el tratamiento con 18 eritropoyetina, la administración de otra pauta de hierro intravenoso o la transfusión preoperatoria, las mujeres embarazadas y las reintervenciones de cirugía cardíaca en ocasiones sucesivas durante el periodo a estudio en pacientes con un episodio previo ya incluido en el estudio. Se identificaron 338 pacientes que cumplieron los criterios de selección, de los que un total de 191 pacientes recibieron una dosis de hierro carboximaltosa (grupo tratado) en el mes anterior a la cirugía, mientras que 147 no se trataron (grupo no tratado). Para cada uno de los dos grupos se calcularon medias y desviaciones estándar para las variables cuantitativas. Para la detección de posibles diferencias significativas en los promedios de variables de interés se utilizó la prueba t de comparación de medias o la prueba U de Mann-Whitney en función del tamaño de la muestra y la distribución de los datos. En el caso de las variables cualitativas se obtuvieron frecuencias y porcentajes y se utilizaron las pruebas Ji-cuadrado o prueba exacta de Fisher cuando fue necesario. Para determinar potenciales diferencias significativas en la variación de determinadas variables resultado (cuantitativas) en dos instantes de tiempo (ej. Valor basal vs Valor previo a la cirugía) se utilizó, según las características de la variable y el tamaño muestral la prueba t para muestras apareadas o la prueba por rangos de Wilcoxon. Para el análisis de la posible asociación entre las variables de interés (incluida la variable grupo) y el incremento de hemoglobina, la anemia preoperatoria, el incremento del filtrado glomerular, la transfusión, el número de concentrados de hematíes transfundidos, la estancia hospitalaria o en la Unidad de Cuidados Intensivos, reingreso y morbimortalidad se emplearon modelos de regresión logística multivariante, regresión ordinal multivariante (comprobando previamente la hipótesis de líneas paralelas) y regresión lineal múltiple dependiendo de las características de la variable y ajustando por diversas variables sociodemográficas y clínicas. En todos los casos las variables se introdujeron en el modelo de forma progresiva, analizando los cambios en cada paso, así como los posibles efectos de interacción. La menor hemoglobina basal del grupo tratado (12,96±1,39 vs 13,59±1,45 g.l-1, p<0.005), no impidió que el tratamiento aumentara significativamente la proporción de pacientes sin anemia preoperatoria (79.1% vs 63.3%) (odds ratio para la mejora, 0.456; 95% intervalo de confianza [CI], 0,281 a 740; P<0.001), gracias al incremento significativo de la hemoglobina (odds ratio 8,075; 95% CI, 5,198 a 10,953; P<0.001). Ese efecto positivo fue evidente en 19 pacientes con deficiencia funcional de hierro y sin anemia basal, si bien fue aún más marcado en aquellos con deficiencia absoluta y anemia basal. La mejora significativa de la hemoglobina preoperatoria y el filtrado glomerular preoperatorio (odds ratio para la mejora, 2.515; 95% intervalo de confianza [CI], -0.436 a 5.466; P 0.095), se asoció a una significativamente menor proporción de pacientes con anemia preoperatoria, que se acompañó de una reducción del riesgo de transfusión (odds ratio para la mejora, 0.424; 95% intervalo de confianza [CI], 0.258 a 0.696; P 0.001) y del número de concentrados de hematíes transfundidos. Además, se comprobó que, en pacientes con deficiencia de hierro, la ausencia de anemia basal no aseguró una hemoglobina óptima que evitara la anemia en el momento de la cirugía. Por otra parte, no se detectó un efecto del tratamiento sobre la morbimortalidad, si bien el número de éxitos fue muy reducido. La administración de una sola dosis de hierro carboximaltosa a pacientes con deficiencia de hierro con o sin anemia fue segura y no produjo un mayor riesgo de infección ni de otros efectos secundarios graves. La corrección de la deficiencia de hierro es un objetivo terapéutico independiente, en la mejora preoperatoria del paciente y en la optimización de la transfusión en la sustitución electiva de válvula cardíaca.

Health literacy is widespread, but its potential is not recognized. By not recognizing health literacy, patients have the burden of coping with diabetes with renal complications without full knowledge of their responsibility to their health. The focus of the project was to assess participants with diabetes with low health literacy and low mean glomerular filtration rate (eGFR). The project goal was achieved by the assessment of the participants' health literacy and eGFR before and after education for their diabetes, then assessed to determine if teaching the participants would improve their health literacy, lab values, and overall health. Participants were recruited by being patients of the designated clinic and screened for diabetes and low eGFR, for a total of 30 participants. The Brief Health Literacy Screen was used to measure health literacy. The health of the participants was appraised by the laboratory values of eGFR and fasting glucose. The project methodology was an observational design using correlation and 2-sample t analysis with the variables eGFR, fasting glucose, and health literacy. The variables were compared before and after the participants' education. Results showed health literacy with patient education was associated with greater patient self-efficacy and improved fasting glucose numbers, eGFR flows, and health literacy scores. The current health climate shows value in different types of health providers. Social change was defined by the project launching a nurse practitioner as the leader for advancing the treatment plans of chronic kidney disease. This project impacts social change by showing patients in the process of improved health and empowering the patients to be advocates of their own health.

This thesis aims to investigate if the endothelial protein C receptor is expressed in the murine kidney. This was done by performing flow cytometry and Western blot analysis on cultivated murine kidney endothelial cells (mKECs) as well as SDS-PAGE and Western blot analysis on murine kidney tissue. Flow cytometry was also performed on cultivated ARPE19 and 4T1 cells for comparison. It was discovered that ≥95,5% of the mKECs, ≥93,6% of the ARPE19 cells and ≥60,9% of the 4T1 cells express the receptor according to the flow cytometry data. A dot blot was performed to validate the primary antibody used for detection of EPCR in Western blot and SDS-PAGE. According to the dot blot, the primary antibody can be visualised in the dilution range from 1:2000 to 1:10. The dot blot also showed that the secondary antibody binds specifically to the primary antibody. Yet, Western blot analysis did not detect the receptor neither in mKECs nor tissue lysate. This was likely due to the fact that the primary antibody used did not bind specifically to the receptor, and may not be applicable for this method. SDS-PAGE did not show any indication that the receptor was present in the kidney tissue. In conclusion, it was discovered that the EPCR was expressed in the murine kidneys endothelial cells through flow cytometry, but the presented methods for Western blot and SDS-PAGE could not confirm the expression of the receptor.

Introdução: Tenofovir disoproxil fumarate (TDF) é um inibidor da transcriptase reversa análogo nucleotídeo que tem sido usado por gestantes para o tratamento da infecção pelo vírus da imunodeficiência humana (HIV), bem como para a prevenção da transmissão vertical do vírus. Até o momento, não há estudos experimentais ou em humanos sobre a incidência de alterações renais nos fetos expostos a esquemas contendo TDF. Objetivo: Verificar a ocorrência de alterações renais e sistêmicas fetais causadas pelo uso do TDF durante a gestação. Metodologia: Ratos Wistar fêmeas receberam dieta padrão com ou sem adição de TDF (100mg/Kg de dieta) desde uma semana antes do cruzamento até o parto. A prole proveniente do grupo TDF foi colocada com uma mãe adotiva não tratada durante o período de amamentação e foi comparada com a prole de ratas que receberam dieta padrão durante a gestação (grupo controle). Controle e TDF foram acompanhados até três (n=9 para cada grupo) e seis (n=12 e n=10, respectivamente) meses de idade. Foram avaliados: peso corporal (PC) e pressão arterial sistólica (PAS) mensais, contagem de glomérulos, função renal (através do clearance de inulina), parâmetros bioquímicos (proteinúria, colesterol total, sódio e potássio séricos e urinários), e expressão proteica do tecido renal para componentes do sistema renina angiotensina aldosterona (SRAA) e para transportadores de sódio. Resultados: A prole TDF apresentou menor PC ao nascimento em comparação com o controle. Após o 3º mês, o grupo TDF demonstrou um crescimento compensatório, atingindo o sexto mês com maior PC. O peso renal foi menor no grupo TDF, porém, não houve diferença do número de néfrons entre os grupos. O grupo TDF apresentou alterações estruturais glomerulares. Observou-se também um aumento progressivo da PAS após o segundo mês de idade no grupo TDF. Não houve diferença estatística na função renal entre os grupos. Os níveis plasmáticos de aldosterona foram mais elevados no grupo TDF, em associação com um aumento da expressão renal do SRAA. Ratos do grupo TDF apresentaram menor excreção renal de sódio e maior expressão renal de transportadores de sódio. Conclusões: Esta é a primeira descrição, a partir de um modelo experimental, que a utilização do TDF durante a gestação resulta em hiperativação do SRAA, aumento da expressão dos transportadores renais de sódio e hipertensão arterial da prole / Introduction: Tenofovir disoproxil fumarato (TDF) is a nucleotide reverse transcriptase inhibitor that has been used in pregnants for treatment of maternal HIV infection and for prevention of vertical transmission. Currently, there are no published studies providing data regarding the occurrence of renal abnormalities in fetuses exposed to TDF-containing regimens. Objective: To evaluate the occurrence of systemic and renal abnormalities in offspring of Wistar rats exposed to TDF during pregnancy. Methods: Female Wistar rats received a standard diet, with or without addition of TDF (100 mg/Kg diet), one week before mating and during pregnancy. Offspring from the TDF group were placed with an untreated foster mother during breastfeeding and compared with offspring from rats maintained on a standard diet during mating and pregnancy (control). Control and TDF were followed up at three and six months of age. Analyzed data: monthly body weight and systolic blood pressure (SBP), glomerular counting, renal function, biochemical parameters, and renal tissue immunoblotting for renin angiotensin aldosterone system (RAAS) and renal sodium transporters. Results: TDF offspring showed lower birth weight compared with the control group. After the third month, growth among the TDF group experienced a rapid catch-up. SBP increased progressively after the second month of age in the TDF group. The nephron number did not differ between groups. The TDF group showed glomerular structural changes. There was no significant difference in renal function between the groups studied. Plasma aldosterone was higher in the TDF group, associated with a significant increase in renal expression of RAAS. The TDF rats showed upregulation of renal sodium transporters and consequently lower urinary sodium excretion. Conclusions: This is the first demonstration using an experimental model that maternal exposure to TDF during gestation results in over activation of RAAS, upregulation of renal sodium transporters and hypertension of the offspring

A Síndrome da Imunodeficiência Adquirida (AIDS) é um problema de saúde pública. O Tenofovir Disoproxil Fumarato (TDF) foi o primeiro inibidor do nucleotídeo da transcriptase reversa e é a droga mais recomendada para o tratamento da AIDS. Entretanto, o uso prolongado de TDF está associado com a nefrotoxicidade. A deficiência de vitamina D tem alta prevalência em indivíduos infectados com o Vírus da Imunodeficiência Humana (HIV). A vitamina D participa da regulação de atividades fisiológicas de diversos órgãos, incluindo o rim, oferecendo proteção contra as lesões ocasionadas por diferentes causas. Portanto, pacientes com níveis baixos de vitamina D infectados com o HIV podem apresentar complicações renais e cardiovasculares durante a terapia antirretroviral. Sendo assim, a carência desta vitamina pode acelerar a progressão da doença renal. Tendo em vista o aumento da incidência de hipovitaminose D na população mundial, esse trabalho tem o objetivo de verificar os mecanismos que levam ao desenvolvimento da lesão renal em ratos depletados de vitamina D submetidos ao tratamento com TDF. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão por 60 dias; dVD, animais que receberam dieta depletada em vitamina D por 60 dias; TDF, animais que receberam dieta padrão por 60 dias com a adição de TDF (50 mg/kg de dieta) nos últimos 30 dias; e dVD+TDF, animais que receberam dieta depletada em vitamina D por 60 dias com a adição de TDF nos últimos 30 dias. Ao final dos 60 dias, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. O tratamento com TDF levou a insuficiência renal observada pela queda da filtração glomerular e lesão tubular proximal com aparecimento de fosfatúria ocasionada pela diminuição do cotransportador sódio/fosfato subtipo IIa. Essas alterações foram acompanhadas de hipertensão e modificações no perfil lipídico. A deficiência em vitamina D associada à administração de TDF agravou os efeitos renovasculares e a nefrotoxicidade induzida pelo TDF, pelo menos em parte, devido ao aumento nos marcadores de estresse oxidativo e a participação do sistema renina-angiotensina-aldosterona. Portanto, é essencial monitorar os níveis de vitamina D em pacientes infectados com o HIV tratados com TDF / Acquired Immunodeficiency Syndrome (AIDS) has become one of the world\'s most serious health problem. Tenofovir Disoproxil Fumarate (TDF) was the first available nucleotidic reverse transcription inhibitor and is a widely prescribed antiretroviral medication for treatment of Human Immunodeficiency Virus (HIV). However, the long-term use of TDF has been associated with a number of toxicities, including those affecting the kidney. Vitamin D deficiency is prevalent among HIVinfected individuals. Vitamin D not only regulates numerous physiological activities of multiple organ systems, but also protects the kidney from injury from different causes. Thus, HIV-infected subjects with low levels of vitamin D could experience increased complications during antiretroviral therapy, such as cardiovascular disease and renal impairment. In view of the high worldwide incidence of hypovitaminosis D, the aim of this study was to investigate the effects of vitamin D deficiency on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; dVD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and dVD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. At the end of the protocol, animals were euthanized and blood, urine and tissue samples were collected in order to evaluate the mechanisms responsible for renal injury. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of reninangiotensin- aldosterone system (RAAS). TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and vitamin D deficiency aggravated renovascular effects and TDFinduced nephrotoxicity at least in part by the increase of oxidative stress and the involvement of RAAS. Hence, it is important to monitor vitamin D levels in HIV-infected patients treated with TDF

A Síndrome da Imunodeficiência Adquirida (AIDS) é um problema de saúde pública. O Tenofovir Disoproxil Fumarato (TDF) foi o primeiro inibidor do nucleotídeo da transcriptase reversa e é a droga mais recomendada para o tratamento da AIDS. Entretanto, o uso prolongado de TDF está associado com a nefrotoxicidade. A deficiência de vitamina D tem alta prevalência em indivíduos infectados com o Vírus da Imunodeficiência Humana (HIV). A vitamina D participa da regulação de atividades fisiológicas de diversos órgãos, incluindo o rim, oferecendo proteção contra as lesões ocasionadas por diferentes causas. Portanto, pacientes com níveis baixos de vitamina D infectados com o HIV podem apresentar complicações renais e cardiovasculares durante a terapia antirretroviral. Sendo assim, a carência desta vitamina pode acelerar a progressão da doença renal. Tendo em vista o aumento da incidência de hipovitaminose D na população mundial, esse trabalho tem o objetivo de verificar os mecanismos que levam ao desenvolvimento da lesão renal em ratos depletados de vitamina D submetidos ao tratamento com TDF. Ratos Wistar foram divididos em quatro grupos: controle, animais que receberam dieta padrão por 60 dias; dVD, animais que receberam dieta depletada em vitamina D por 60 dias; TDF, animais que receberam dieta padrão por 60 dias com a adição de TDF (50 mg/kg de dieta) nos últimos 30 dias; e dVD+TDF, animais que receberam dieta depletada em vitamina D por 60 dias com a adição de TDF nos últimos 30 dias. Ao final dos 60 dias, os animais foram submetidos à eutanásia, amostras de sangue, urina e o tecido renal foram coletados para a análise dos mecanismos de lesão renal. O tratamento com TDF levou a insuficiência renal observada pela queda da filtração glomerular e lesão tubular proximal com aparecimento de fosfatúria ocasionada pela diminuição do cotransportador sódio/fosfato subtipo IIa. Essas alterações foram acompanhadas de hipertensão e modificações no perfil lipídico. A deficiência em vitamina D associada à administração de TDF agravou os efeitos renovasculares e a nefrotoxicidade induzida pelo TDF, pelo menos em parte, devido ao aumento nos marcadores de estresse oxidativo e a participação do sistema renina-angiotensina-aldosterona. Portanto, é essencial monitorar os níveis de vitamina D em pacientes infectados com o HIV tratados com TDF / Acquired Immunodeficiency Syndrome (AIDS) has become one of the world\'s most serious health problem. Tenofovir Disoproxil Fumarate (TDF) was the first available nucleotidic reverse transcription inhibitor and is a widely prescribed antiretroviral medication for treatment of Human Immunodeficiency Virus (HIV). However, the long-term use of TDF has been associated with a number of toxicities, including those affecting the kidney. Vitamin D deficiency is prevalent among HIVinfected individuals. Vitamin D not only regulates numerous physiological activities of multiple organ systems, but also protects the kidney from injury from different causes. Thus, HIV-infected subjects with low levels of vitamin D could experience increased complications during antiretroviral therapy, such as cardiovascular disease and renal impairment. In view of the high worldwide incidence of hypovitaminosis D, the aim of this study was to investigate the effects of vitamin D deficiency on TDF-induced nephrotoxicity. Wistar rats were divided into four groups: control, receiving a standard diet for 60 days; dVD, receiving a vitamin D-free diet for 60 days; TDF, receiving a standard diet for 60 days with the addition of TDF (50 mg/kg food) for the last 30 days; and dVD+TDF receiving a vitamin D-free diet for 60 days with the addition of TDF for the last 30 days. At the end of the protocol, animals were euthanized and blood, urine and tissue samples were collected in order to evaluate the mechanisms responsible for renal injury. TDF led to impaired renal function, hyperphosphaturia, hypophosphatemia, hypertension and increased renal vascular resistance due to downregulation of the sodium-phosphorus cotransporter and upregulation of reninangiotensin- aldosterone system (RAAS). TDF also increased oxidative stress, as evidenced by higher TBARS and lower GSH levels, and induced dyslipidemia. Association of TDF and vitamin D deficiency aggravated renovascular effects and TDFinduced nephrotoxicity at least in part by the increase of oxidative stress and the involvement of RAAS. Hence, it is important to monitor vitamin D levels in HIV-infected patients treated with TDF

Introdução: Tenofovir disoproxil fumarate (TDF) é um inibidor da transcriptase reversa análogo nucleotídeo que tem sido usado por gestantes para o tratamento da infecção pelo vírus da imunodeficiência humana (HIV), bem como para a prevenção da transmissão vertical do vírus. Até o momento, não há estudos experimentais ou em humanos sobre a incidência de alterações renais nos fetos expostos a esquemas contendo TDF. Objetivo: Verificar a ocorrência de alterações renais e sistêmicas fetais causadas pelo uso do TDF durante a gestação. Metodologia: Ratos Wistar fêmeas receberam dieta padrão com ou sem adição de TDF (100mg/Kg de dieta) desde uma semana antes do cruzamento até o parto. A prole proveniente do grupo TDF foi colocada com uma mãe adotiva não tratada durante o período de amamentação e foi comparada com a prole de ratas que receberam dieta padrão durante a gestação (grupo controle). Controle e TDF foram acompanhados até três (n=9 para cada grupo) e seis (n=12 e n=10, respectivamente) meses de idade. Foram avaliados: peso corporal (PC) e pressão arterial sistólica (PAS) mensais, contagem de glomérulos, função renal (através do clearance de inulina), parâmetros bioquímicos (proteinúria, colesterol total, sódio e potássio séricos e urinários), e expressão proteica do tecido renal para componentes do sistema renina angiotensina aldosterona (SRAA) e para transportadores de sódio. Resultados: A prole TDF apresentou menor PC ao nascimento em comparação com o controle. Após o 3º mês, o grupo TDF demonstrou um crescimento compensatório, atingindo o sexto mês com maior PC. O peso renal foi menor no grupo TDF, porém, não houve diferença do número de néfrons entre os grupos. O grupo TDF apresentou alterações estruturais glomerulares. Observou-se também um aumento progressivo da PAS após o segundo mês de idade no grupo TDF. Não houve diferença estatística na função renal entre os grupos. Os níveis plasmáticos de aldosterona foram mais elevados no grupo TDF, em associação com um aumento da expressão renal do SRAA. Ratos do grupo TDF apresentaram menor excreção renal de sódio e maior expressão renal de transportadores de sódio. Conclusões: Esta é a primeira descrição, a partir de um modelo experimental, que a utilização do TDF durante a gestação resulta em hiperativação do SRAA, aumento da expressão dos transportadores renais de sódio e hipertensão arterial da prole / Introduction: Tenofovir disoproxil fumarato (TDF) is a nucleotide reverse transcriptase inhibitor that has been used in pregnants for treatment of maternal HIV infection and for prevention of vertical transmission. Currently, there are no published studies providing data regarding the occurrence of renal abnormalities in fetuses exposed to TDF-containing regimens. Objective: To evaluate the occurrence of systemic and renal abnormalities in offspring of Wistar rats exposed to TDF during pregnancy. Methods: Female Wistar rats received a standard diet, with or without addition of TDF (100 mg/Kg diet), one week before mating and during pregnancy. Offspring from the TDF group were placed with an untreated foster mother during breastfeeding and compared with offspring from rats maintained on a standard diet during mating and pregnancy (control). Control and TDF were followed up at three and six months of age. Analyzed data: monthly body weight and systolic blood pressure (SBP), glomerular counting, renal function, biochemical parameters, and renal tissue immunoblotting for renin angiotensin aldosterone system (RAAS) and renal sodium transporters. Results: TDF offspring showed lower birth weight compared with the control group. After the third month, growth among the TDF group experienced a rapid catch-up. SBP increased progressively after the second month of age in the TDF group. The nephron number did not differ between groups. The TDF group showed glomerular structural changes. There was no significant difference in renal function between the groups studied. Plasma aldosterone was higher in the TDF group, associated with a significant increase in renal expression of RAAS. The TDF rats showed upregulation of renal sodium transporters and consequently lower urinary sodium excretion. Conclusions: This is the first demonstration using an experimental model that maternal exposure to TDF during gestation results in over activation of RAAS, upregulation of renal sodium transporters and hypertension of the offspring

Faible masse musculaire a été peu étudiée chez les patients avant le stade terminal de la maladie rénale chronique (MRC). Nous avons évalué la masse musculaire à partir de la créatininurie des 24h pour étudier ses déterminants, son évolution avec le déclin de la fonction rénale ainsi que ses liens avec les risques de progression vers l’insuffisance rénale terminale traitée (IRTT) et de décès avant IRTT. Dans la cohorte NephroTest incluant 1429 patients avec une MRC stades 1 à 4, le débit de filtration glomérulaire a été mesuré par la clairance du 51Cr-EDTA (DFGm) et estimé par l’équation CKD EPI (DFGe). La créatininurie moyenne à l’inclusion diminuait de 15.3±3.1 à 12.1±3.3 mmol/24 chez les hommes et de 9.6±1.9 à 7.6±2.5 chez les femmes, pour une baisse du DFGm de ≥ 60 à < 15 mL/min/1.73 m2. Être plus âgé, avoir un diabète, un faible IMC ou un niveau faible de protéinurie et d’apports protidiques était associé à un niveau faible de créatininurie. Un déclin annuel du DFGm de 5 mL/min/1.73 m2 était lié à une baisse de créatininurie, indépendamment de ces déterminants. Au cours d’un suivi médian de 3.6 ans, 229 patients ont développé une IRTT, et 113 sont décédés avant IRTT. Après ajustement sur les facteurs de confusion, le hasard ratio (HR) était de 1.6 (0.88-2.9) pour le risque de décès et de 0.60 (0.39-0.91) pour le risque d’IRTT, dans le 1er vs 4ème quartile de créatininurie. La baisse de la créatininurie apparait précocement dans la MRC et est liée au décès avant dialyse. La diminution du risque d’IRTT pourrait s’expliquer par un démarrage plus tardif de la dialyse en raison d’une surestimation du DFGm par le DFGe chez les patients avec une faible créatininurie. / Mainly described in patients on dialysis, muscle wasting has received little attention in early stage chronic kidney disease (CKD). We used 24-hour creatininuria to assess determinants of low muscle mass and its putative associations with CKD outcomes, using data from the NephroTest cohort, including 1429 non-dialysis patients with CKD stages 1 to 5. Kidney function was assessed with both measured (mGFR, by 51Cr-EDTA renal clearance) and estimated glomerular filtration rate (eGFR, by CKD-EPI equation). End-stage renal disease (ESRD) and pre-ESRD death were the main studied outcomes. The mean baseline creatininuria decreased from 15.3±3.1 to 12.1±3.3 mmol/24 h in men and from 9.6±1.9 to 7.6±2.5 in women, when mGFR fell from ≥ 60 to < 15 mL/min/1.73 m2. Other determinants of low creatininuria were an older age, diabetes, a lower body mass index, a lower level of proteinuria or protein intake. A fast annual decline in mGFR of 5 mL/min/1.73 m2 was linked with a 2-fold decrease in creatininuria, independent of changes in protein intake and other determinants of muscle mass. Over a median follow-up of 3.6 years, 229 patients developed ESRD and 113 patients died before ESRD. After adjustment for confounders, patients with low muscle mass showed a significantly higher risk for pre-ESRD death (HR 1.6, 95% CI 0.88-2.9), but a lower risk for ESRD (HR 0.60, 95% CI 0.39-0.91). The latter was reversed (HR 1.5, 95% CI 1.01-2.4) when mGFR was replaced by eGFR. Decrease in 24-hour creatininuria may appear early in CKD patients, is related to pre-ESRD death. The lower risk for ESRD may reflect later dialysis start due to overestimation of true GFR by eGFR in patients with low muscle mass.