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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.
51

Alterações renais precoces em um modelo experimental que combina hipertensão arterial genetica e diabetes mellitus : efeitos do tratamento anti-hipertensivo / Early renal abnormalities in a experimental model that combind genetic arterial hypertension and diabetes mellitus : effect of anty-hypertensive treatment

Amazonas, Roberto Bleuel 09 April 2006 (has links)
Orientador: Jose Butori Lopes de Faria / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-07T11:40:18Z (GMT). No. of bitstreams: 1 Amazonas_RobertoBleuel_D.pdf: 3511441 bytes, checksum: b4fcb466c8675ae1dba5206babaf5e15 (MD5) Previous issue date: 2006 / Resumo: No diabetes mellitus (DM), a hipertensão arterial (HA) é o principal fator associado ao desenvolvimento e progressão da nefi-opatia diabética (ND). Os mecanismos de interação entre HA e DM no agravamento da ND são pouco conhecidos. No presente trabalho investigamos a contribuição da HA nas alterações renais precoces de um modelo que combina HA e DM. Ratos machos com 4 semanas de idade, espontaneamente hipertensos (SHR) e seus controles Wistar Kyoto (WKY), foram tornados diabéticos através da injeção endovenosa de estreptozotocina. Os ratos SHR com DM foram randomizados para tratamento com captopril, losartan, terapia triplice (hidroclorotiazida, reserpina e hidralazina) e nenhum tratamento por 20 dias. O aumento na pressão sistólica foi igualmente previnido pelos diversos esquemas anti-hipertensivos. A expressão glomerular de nemna estava reduzida nos animais SHR controle em relação aos animais WKY, e de forma mais acentuada no grupo SHR DM. A prevenção da HA foi capaz de evitar a redução na nemna, bem como reduzir a albuminúria. A superfície, expressão de fibronectina e TGF 131 glomerulares estavam significativamente aumentadas no grupo SHR diabético em relação ao grupo SHR controle e foi prevenida pelos diversos tratamentos. A replicação de células renais foi significativamente menor no grupo SHR diabético em relação ao controle, e restaurado com a prevenção da hipertensão arterial. A expressão glomerular de p27Kipl estava aumentada no grupo SHR diabético, mas não foi modificada pelo tratamento anti-hipertensivo. Em conclusão a presença da HA em ratos diabéticos induziu o aparecimento de alterações renais precoces que puderam ser previnidas com o tratamento anti-hipertensivo, independente da classe de droga utilizada / Abstract: In diabetic patients hypertension is the main secondary factor associated with the development and progression of renal disease. However, the mechanism of interaction between diabetes and hypertension to exacerbate diabetic renal disease is poorly understood. The aim of this study was to evaluate the effect of presence of hypertension had on nephrin expression, glomerular hypertrophy, renal celI replication and accumulation of glomerular TGF f3 and fibronectin in a model of genetic hypertension and experimental diabetes mellitus. Four-week-old spontaneously hypertensive rats (SHR) and their normotensive control Wistar K yoto (WKY) were rendered diabetic by means of intravenously injection of streptozotocin. To further assess the contribution ofhypertension to renal abnormalities diabetic SHR were randomÍzed for no treatment, or for treatment with captopril, losartan or triple therapy (hydrochlorothiazide, reserpine and hydralazine) for 20 days. Increase in systolic blood pressure was equally prevented by captopril (113 :i: 9mmHg), losartan (115 :!:: 16) and triple therapy (108 :i: 12, p<0.005). Glomerular expression of nephrin was reduced in SHR and further diminished in diabetic SHR in comparison with controls and the antihypertensive treatment prevents the reduction in glomerular expression of nephrin. Glomerular sÍze was higher (p<0.005) in diabetic SHR (27,300 :i: 2130 Jim2) compared with non-diabetic SHR (23,800 :!:: 307). The antihypertensive therapy with captopril (23,900 :i: 175), losartan (23,800 :i:120), and triple therapy (23,400 :i:21O) prevented the glomerular enlargement in diabetic SHR. Glomerular expression of TGF f3 and fibronectin was significantly increased in diabetic SHR as compared to the controls, and was prevented with captopril, losartan and triple therapy. The number of replicating glomerular cell significantly decreased in diabetic SHR and it was restored by alI three antihypertensive regimes. The glomerular expression of p27Kipl was significantly higher in diabetic SHR but it was not modified by antihypertensive treatment. In diabetic rats the presence of genetic hypertension induced early renal abnormalities that were prevented by strict control of blood pressure. These abnormalities may be involved in the mechanism of interaction between diabetes and hypertension to exacerba te renal disease / Doutorado / Clinica Medica / Doutor em Clínica Médica
52

Predictive Relationship between Treatment Adherence, Glycated Hemoglobin and Diabetic Complications Among Jamaicans

Nwaukwa, Christian Anaba 01 January 2018 (has links)
Patient nonadherence to physicians' prescribed therapeutic regimen is the greatest challenge in the effective treatment of patients with diabetes worldwide. Scientific evidence has revealed that nonadherence to prescribed medication could result in diabetic complications such as cardiovascular disease, retinopathy, nephropathy, and neuropathic diabetic foot ulcers. The purpose of this study was to explore predictive relationships between levels of adherence to antidiabetic medications, patient HbA1c levels, and diabetic complications among Jamaicans, an understudied population. The research question that guided this study was: Do the patient level of adherence and HbA1c levels have any predictive relationship with the severity of diabetic complications (cardiovascular disease, retinopathy, nephropathy and neuropathic foot ulcer) among Jamaicans after controlling for age and gender? The theory of planned behavior was used to guide the study. Data regarding diabetic complications were collected from 119 records during a cross-sectional review of patient dockets. Level of adherence was determined from an interviewer-administered Morisky 8-item adherence scale. A multiple regression analysis revealed that lower levels of patient adherence to treatment and higher HbA1c levels predicted greater severity of cardiovascular disease (p = .000; p = .000), retinopathy (p = .009; p =.090), nephropathy (p =.007; p =.001) and diabetic neuropathic foot ulcers (p =.027; p =.001). Findings from this study will contribute to the knowledge base on diabetic medication nonadherence and may encourage health care professionals to advocate for better medication adherence strategies among people with diabetes.
53

Ablation of the N-type calcium channel ameliorates diabetic nephropathy with improved glycemic control and reduced blood pressure / N型カルシウムチャネルの欠損による糖代謝の改善と血圧の低下を伴う糖尿病性腎症軽減作用に関する研究

Ohno, Shoko 23 January 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20080号 / 医博第4173号 / 新制||医||1018(附属図書館) / 33196 / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 川口 義弥, 教授 小川 修 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
54

Upplevelser av att leva med diabetesnefropati - En kvalitativ intervjustudie

Nilsson Öst, Lotten, Oziegbe, Blessing Ngozi January 2023 (has links)
Abstract                                                                               Bakgrund: Både nationellt och internationellt är diabetesnefropati den vanligast bakomliggande orsaken till njursvikt, och svarar för ca en fjärdedel av den njursvikt som leder till dialysbehandling och njurtransplantation. Det kan drabba unga och äldre personer med både typ 1-diabetes och typ 2-diabetes. Syfte: Att beskriva hemodialysbehandlade personers upplevelser av att leva med diabetesnefropati utifrån Katie Erikssons omvårdnadsteori. Metod: Kvalitativ design. Åtta personer med diabetesnefropati och dialysbehov intervjuades. Data analyserades genom en kvalitativ innehållsanalys med en deduktiv ansats baserad på Katie Eriksons omvårdnadsteori. Resultat: Resultatet visade att personernas livssituation förändrades. De upplevde både kroppsliga och psykiska symtom samt att även deras sociala relationer påverkades. De lärde sig att hantera sin situation genom att acceptera sin sjukdom. Att ha familj och anhöriga var av stor betydelse för emotionalt stöd för att kunna uppleva välbefinnande. Slutsats: Diabetessjuksköterskor behöver ha en grundkunskap om individers upplevelser av att leva med hemodialysbehandlad diabetesnefropati för att hitta bättre sätt att kunna stötta dem. Med tidig information och stöttning av personer med risk för diabetesnefropati, kan risken för utveckling av diabetesnefropati minskas eller undvikas. / Abstract Background: Both nationally and internationally, diabetic nephropathy is the most common underlying cause, and accounts for about a quarter of kidney failure that leads to dialysis treatment and kidney transplantation. It can affect both young and adult people with diabetes as an underlying disease. Chronic kidney disease can result from both type 1 diabetes and type 2 diabetes. Purpose: To describe persons in hemodialysis experiences of living with diabetic nephropathy based on Katie Eriksson's nursing theory. Method: Qualitative design. Eight persons with diabetic nephropathy and need for dialysis were interviewed. The data was analysed through a qualitative content analysis with a deductive approach based on Katie Erikson's nursing theory. Results: The results showed that the participants' life situation changed. The participants experienced both physical and psychological symptoms and that their social relationships were also affected. They learned to cope with their situation by accepting their illness. Having family and relatives was of great importance for emotional support to be able to experience well-being. Conclusion: Diabetes nurses need to have a basic knowledge of individuals' experiences of living with hemodialysis-treated diabetic nephropathy to find better ways to support them. With early information and support of patients at risk of diabetic nephropathy, the risk of developing diabetic nephropathy can be reduced or avoided.
55

Activated Protein C Ameliorates Tubular Mitochondrial Reactive Oxygen Species and Inflammation in Diabetic Kidney Disease

Rana, Rajiv, Manoharan, Jayakumar, Gupta, Anubhuti, Gupta, Dheerendra, Elwakiel, Ahmed, Khawaja, Hamzah, Fatima, Sameen, Zimmermann, Silke, Singh, Kunal, Ambreen, Saira, Gahdi, Ihsan, Biemann, Ronald, Jiang, Shihai, Shahzad, Khurrum, Kohli, Shrey, Isermann, Berend 01 November 2023 (has links)
Diabetic kidney disease (DKD) is an emerging pandemic, paralleling the worldwide increase in obesity and diabetes mellitus. DKD is now the most frequent cause of end-stage renal disease and is associated with an excessive risk of cardiovascular morbidity and mortality. DKD is a consequence of systemic endothelial dysfunction. The endothelial-dependent cytoprotective coagulation protease activated protein C (aPC) ameliorates glomerular damage in DKD, in part by reducing mitochondrial ROS generation in glomerular cells. Whether aPC reduces mitochondrial ROS generation in the tubular compartment remains unknown. Here, we conducted expression profiling of kidneys in diabetic mice (wild-type and mice with increased plasma levels of aPC, APChigh mice). The top induced pathways were related to metabolism and in particular to oxidoreductase activity. In tubular cells, aPC maintained the expression of genes related to the electron transport chain, PGC1-α expression, and mitochondrial mass. These effects were associated with reduced mitochondrial ROS generation. Likewise, NLRP3 inflammasome activation and sterile inflammation, which are known to be linked to excess ROS generation in DKD, were reduced in diabetic APChigh mice. Thus, aPC reduces mitochondrial ROS generation in tubular cells and dampens the associated renal sterile inflammation. These studies support approaches harnessing the cytoprotective effects of aPC in DKD.
56

The Effect of STAT5 on Inflammation-Related Gene Expression in Diabetic Mouse Kidneys

Shaw, Samantha J. 12 June 2014 (has links)
No description available.
57

L’expression de SHP-1 induite par l’hyperglycémie inhibe les actions de l’insuline dans les podocytes / Expression of SHP-1 induced by hyperglycemia prevents insulin actions in podocytes

Drapeau, Nicolas January 2014 (has links)
Résumé : Les podocytes, cellules épithéliales rénales, sont nécessaires au maintien de la structure et de la fonction de filtration des glomérules rénaux. La dédifférenciation et l’apoptose des podocytes sont des évènements précoces de la néphropathie diabétique. Des études ont rapporté que l’insuline est nécessaire à la survie des podocytes puisque la délétion du récepteur à l’insuline dans les podocytes de souris entraîne une pathologie glomérulaire semblable à la néphropathie. D’autres études ont montré que la protéine tyrosine phosphatase Src homology-2 domain-containing phosphatase-1 (SHP-1) inhibe les voies de signalisation de l’insuline au niveau du foie et du muscle en déphosphorylant la sous-unité bêta du récepteur à l’insuline (IRβ) et la kinase Phosphatidylinositide 3-kinase (PI3K). Il a récemment été démontré que l’expression de SHP-1 est élevée dans les cortex rénaux de souris diabétiques. Nous avons donc émis l’hypothèse que l’expression de SHP-1 induite par l’hyperglycémie altère les actions de l’insuline dans les podocytes. Nous avons premièrement utilisé un modèle in vivo de souris diabétiques de type 1 (Ins2+/C96Y; Akita). Comparées aux souris contrôles (Ins2+/+), les souris Akita présentaient une apoptose élevée des podocytes ainsi qu’une perte des pédicelles. La phosphorylation de la protéine kinase B (Akt) et de Extracellular signal-regulated kinase 1/2 (ERK1/2), suite à une injection systémique d’insuline, était également significativement diminuée dans les cortex rénaux des souris Akita. Cette diminution correspondant à une résistance à l’insuline corrélait avec une augmentation de deux fois de l’expression de SHP-1 dans les glomérules. Nous avons ensuite utilisé une lignée immortalisée de podocytes murins en culture et avons observé que l’exposition à des concentrations élevées de glucose (HG; 25 mM) pendant 96 h, entraînait l’augmentation de l’expression de marqueurs apoptotiques et de l’activité enzymatique de caspase-3/7 en comparaison aux concentrations normales de glucose (NG; 5,6 mM). L’exposition en HG a augmenté l’expression de l’ARNm et protéique de SHP-1, en plus de réduire la signalisation de l’insuline dans les podocytes. La surexpression de la forme dominante-négative de SHP-1 dans les podocytes a permis de renverser les effets de HG et de restaurer les actions de l’insuline. Finalement, l’augmentation de l’expression de SHP-1, tant in vivo qu’in vitro, a été directement corrélée à son association avec IRβ et à la diminution de la phosphorylation de IRβ, Akt et ERK1/2 suite à une stimulation à l’insuline. En conclusion, nous avons montré que l’expression élevée de SHP-1 dans les glomérules cause une résistance à l’insuline et la mort des podocytes contribuant ainsi à la néphropathie diabétique. // Abstract : Podocytes are epithelial renal cells required to preserve glomerular structure and filtration. Their dedifferentiation and apoptosis are early events of diabetic nephropathy progression. Previous studies have shown that insulin action is critical for podocyte survival since deletion of its receptor lead to a glomerular pathology similar to nephropathy. It has also been demonstrated that Src homology-2 domain-containing phosphatase-1 (SHP-1), a protein tyrosine phosphatase, inhibits insulin signaling pathway in liver and muscle by dephosphorylating tyrosine residues on insulin receptor beta-subunit (IRβ) and the Phosphatidylinositide 3-kinase (PI3K). A recent study concluded that SHP-1 is elevated in kidney cortex of type 1 diabetic mice. We hypothesized that hyperglycemia-induced SHP-1 expression may affect insulin actions in podocytes. To confirm this hypothesis, we used type 1 diabetic Akita mice (Ins2+/C96Y). Compared to control littermate mice (Ins2+/+), Akita mice developed elevated podocyte foot process effacement and podocyte apoptosis. In contrast to control mice, insulin-stimulated protein kinase B (Akt) and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation was remarkably reduced in renal podocytes of Akita mice. This phosphorylation diminution associated to a renal insulin resistance was correlated with a two-fold increase of SHP-1 expression in the glomeruli. We then used cultured murine podocytes cell line to confirm our in vivo results. Podocytes exposed to high glucose concentration (HG; 25 mM) for 96 h exhibited high levels of apoptotic markers and caspase-3/7 enzymatic activity as compared to normal glucose concentration (NG; 5,6 mM). HG exposure raised mRNA and protein levels of SHP-1 and reduced the insulin-signaling pathway in podocytes. Overexpression of dominant-negative SHP-1 in podocytes prevented HG effects and restored insulin actions. Finally, elevated SHP-1 expression induced by high glucose levels was directly correlated to an increased association with insulin receptor-β subunit (IRβ) in vitro and in vivo. This association is therefore leading to the reduction of both IRβ phosphorylation and insulin-stimulated Akt and ERK phosphorylation. In conclusion, our results showed that high levels of SHP-1 in glomeruli cause insulin resistance and podocyte loss, thereby contributing to diabetic nephropathy.
58

Effet du bosentan sur les niveaux d'inflammation systémique et rénale chez des patients avec néphropathie diabétique traités par bloqueurs de récepteurs de l'angiotensine II

Tubail, Zead 05 1900 (has links)
Outre les facteurs métaboliques et hémodynamiques, l’inflammation est actuellement considérée comme un facteur pathogénique potentiel de la néphropathie diabétique (ND), pouvant contribuer à l’initiation et à la progression de la maladie. Les mécanismes menant au développement de l’inflammation rénale dans la ND sont encore peu connus, bien qu’une augmentation d’activité des systèmes rénine angiotensine (RAS) et de l’endothéline (ET) semble y contribuer. L’objectif général de cette étude mono-centre, à double aveugle, randomisée et incluant un groupe placebo était de démontrer que l’inhibition simultanée du RAS et du système de l’ET chez des patients avec ND induisait des effets rénoprotecteurs et anti-inflammatoires supérieurs à ceux observés par blocage du RAS seul. L’objectif spécifique de notre étude était d’évaluer la possibilité que l’administration d’un bloqueur des récepteurs de l’ET-1, le bosentan, à des patients atteints de ND et traités par bloqueurs des récepteurs de l’angiotensine II (BRA), réduisait, chez ces derniers, la protéinurie et les marqueurs inflammatoires systémiques et rénaux. Ce travail constitue un rapport d’un cas clinique et illustre les résultats obtenus suite à l’administration pendant 16 semaines du bosentan chez un patient diabétique de type 2 avec néphropathie clinique traité au long cours par BRA. Le protocole de recherche comprenait 6 visites médicales à 4 semaines d’intervalle, la première visite (V1) correspondant au recrutement du patient, la deuxième visite (V2) constituant le temps 0 de l’étude et la dernière visite (V6) représentant la fin de l’étude. Des échantillons de sang et d’urine étaient prélevés à 3 reprises soit à V2, V4 c’est-à-dire 8 semaines après le début du traitement et à V6 soit 16 semaines après le début du traitement pour mesure des taux sériques et urinaires de divers facteurs pro-inflammatoires incluant l’ET-1, le facteur de nécrose tumorale alpha (TNF-α), l’interleukine-6 (IL-6), le facteur chémoattractant des monocytes-1 (MCP-1), la molécule d’adhésion intracellulaire-1 (ICAM-1), la molécule d’adhésion vasculaire-1 (VCAM-1) et la protéine C-réactive (CRP). Un profil lipidique était aussi déterminé au début et à la fin de l’étude. La fonction rénale était mesurée aux visites V1, V2, V4 et V6 par détermination du taux de filtration glomérulaire (TFG) et de l’excrétion urinaire d’albumine (UAE). Des tests biochimiques de routine étaient aussi faits à chaque visite. La corrélation entre les paramètres inflammatoires et rénaux sous étude et la filtration glomérulaire était enfin déterminée. Nos résultats chez ce sujet ont démontré que le bosentan réduisait l’UAE de 32 % et 35% aux semaines 8 et 16, et ce, sans affecter la pression artérielle ou la filtration glomérulaire. L'effet anti-protéinurique du bosentan était associé à une réduction des concentrations urinaires de VCAM-1, ICAM-1, IL-6, TNF-α et d’ET-1 ainsi qu’à une diminution des concentrations sériques de TNF-α. Le changement dans la protéinurie était corrélé de manière positive avec les changements des niveaux urinaires de VCAM-1 (r=0.86), ICAM-1 (r=0.88), ET-1 (r=0.94), et du TNF-α (r=0.96) ainsi qu’avec les changements des niveaux sériques de TNF-α (r=0.98). Ces données suggèrent que l’inhibition du système de l’ET induit dans la ND des effets rénoprotecteurs additifs à ceux observés par blocage du RAS seul. Ils supportent le concept que l’activation du système de l’ET au niveau rénal, par ses effets inflammatoires, puisse jouer un rôle important dans la pathogenèse de la ND. L’effet anti-inflammatoire et anti-protéinurique du bosentan constitue une découverte intéressante susceptible d’engendrer dans le futur une alternative thérapeutique et préventive dans la prise en charge de la ND. / Apart from metabolic and hemodynamic factors, inflammation has recently been introduced as a potential key pathogenic mechanism involved in the development and progression of diabetic nephropathy (DN). The mechanisms by which renal inflammation occurs in DN are still poorly understood, yet increased renal activity of the renin-angiotensin system (RAS) and endothelin (ET) system may play a key role. The main objective of this mono-centre, double blind, randomized, placebo-controlled study was to demonstrate that concomitant blockade of the RAS and ET system in patients with DN produces greater renal protective effects and exerts greater anti-inflammatory changes than those seen with blockade of the RAS system alone. The specific aim of the study was to evaluate whether administration of bosentan to patients with DN on angiotensin II receptor blockers (ARB) reduces systemic and renal inflammation and improves glomerular filtration. The work presented herein illustrates the results obtained in one type 2 diabetic patient with clinical DN and treated with ARB following the administration of bosentan for 16 weeks. The study protocol included 6 medical visits at 4 weeks interval, with the first visit (V1) being the screening visit and the second visit (V2) being the baseline and randomization visit. Blood and urine samples were taken at V2, after 8 weeks of treatment (V4), and at the end of the study (V6) for determination of serum and urinary inflammatory markers including ET-1, tumour necrosis factor alpha (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and C-reactive protein (CRP). Lipid profile was done at the beginning and end of the study. Renal function was assessed at V1, V2, V4 and V6 by determination of glomerular filtration rate and urinary albumin excretion (UAE). Routine biochemical analyses were done at each visit. Correlation between serum and urinary inflammatory markers and UAE was determined. Our results demonstrated that bosentan administration to this patient reduced UAE by 32% and 35% at weeks 8 and 16, respectively, without affecting blood pressure and glomerular filtration. The anti-proteinuric effect of bosentan was associated with a reduction in urinary levels of VCAM-1, ICAM-1, IL-6, TNF- and ET-1 and a reduction in serum TNF- levels. Change in UAE was positively correlated with changes in urinary levels of VCAM-1 (r=0.86), ICAM-1 (r=0.88), ET-1 (r=0.94), and TNF- (r=0.96) and with change in serum TNF- levels (r=0.98). Our data suggest that blockade of the ET system in top of RAS inhibition exerts additive renoprotective effects in DN. They support the notion that activation of the ET system, by promoting renal inflammation, may play a role in the pathogenesis of DN. The anti-inflammatory and anti-proteinuric effect of bosentan represents an interesting finding which may leads in the future to an alternate therapeutic and preventive for the treatment of DN.
59

Le rôle de la protéine interagissant avec hedgehog (Hhip) dans la formation rénale modulée par le diabète maternel et dans la néphropathie diabétique

Zhao, Xinping 01 1900 (has links)
No description available.
60

A memória hiperglicêmica no rim diabético: marcas metabólicas, moleculares e epigenéticas / The hyperglycemic memory in diabetic kidney: metabolic, molecular, and epigenetic marks

Oliveira, Antonio Anáx Falcão de 10 February 2017 (has links)
A nefropatia diabética (ND) é uma das complicações microvasculares do diabetes e consiste no dano ao parênquima renal por consequência de uma série de fatores hemodinâmicos e moleculares. A ocorrência de ND e de outras complicações mesmo em indivíduos sob adequado controle glicêmico tem sido associada a um fenômeno conhecido como memória metabólica. Neste trabalho foram investigadas vias bioquímicas e moleculares persistentemente alteradas no rim de animais diabéticos tratados após um período inicial de hiperglicemia, com o propósito de entender os mecanismos envolvidos na memória metabólica. Para tanto, ratos com diabetes induzida por estreptozotocina foram mantidos hiperglicêmicos durante 4 semanas (período curto) ou 12 semanas (período longo) e posteriormente tratados com insulina isoladamente ou combinada com metformina (100mg/kg/dia) durante as 4 (período curto) ou 12 (período longo) semanas seguintes. Todos os animais tratados tiveram os seus níveis glicêmicos e função renal normalizados. Os tratamentos também foram capazes de normalizar os níveis elevados de malonaldeído no rim, bem como a excreção aumentada dos adutos de DNA 8-oxo-2\'-desoxiguanosina (8-oxodG) e N2-carboxietil-2\'- desoxiguanosina (CEdG) na urina observados nos animais diabéticos. Níveis aumentados de 8-oxodG foram detectados em DNA mitocondrial (mtDNA), mas não em DNA nuclear, de animais diabéticos apenas no período curto de estudo e também foram normalizados após o controle glicêmico. Nós identificamos uma via gradualmente alterada durante o curso do diabetes que permanece persistentemente alterada após o controle glicêmico tardio. Essa via compreende um declínio precoce do clearance de ácido úrico e expressão da pAMPK, seguida pelo acúmulo de fumarato, expressão aumentada de TGF-&#946;, expressão reduzida de PGC-1&#945; e redução da metilação e hidroximetilação do mtDNA. A redução persistente do clearance de ácido úrico em animais diabéticos tratados pode sustentar as alterações bioquímicas renais prolongadas observadas após o controle glicêmico, e essa regulação é provavelmente mediada pela redução sustentada da expressão de pAMPK e pela indução de inflamação. Este trabalho propõe a primeira consideração do possível papel da hiperuricemia e das alterações bioquímicas subjacentes como parte da memória metabólica na nefropatia diabética. / Diabetic nephropathy is one of the diabetes microvascular complications, and it consists on the damage to the renal parenchyma due to several hemodynamic and molecular factors. The occurrence of diabetic nephropathy and other complications even in those individuals under tight glycemic control has been associated to a phenomenon known as metabolic memory. Here we investigated biochemical and molecular pathways persistently altered in the kidney of diabetic animals treated after a previous period of hyperglycemia, aiming to understand underlying mechanisms in metabolic memory. Streptozotocin-induced diabetic rats were maintained hyperglycemic during 4 (short period) or 12 weeks (long period), and then they were treated with insulin alone or combined with metformin (100 mg/kg/day) for the following 4 or 12 weeks, respectively. All the treated animals had them glycemic levels and renal function normalized. The treatments were also able to control enhanced kidney malondialdehyde levels, as well as the increased urine excretion of the DNA adducts 8-oxo-2\'- deoxyguanosine (8-oxodG) and N2-carboxyethyl-2\'-deoxyguanosine seen in diabetic animals. Increased levels of 8-oxodG were detected in mitochondrial DNA, but not in nuclear DNA of diabetic animals in the short period, and were also recovered after glycemic control. We have identified a kidney pathway that is gradually altered during the course of diabetes and remains persistently changed after late glycemic control. This pathway comprises an early decline of uric acid clearance and pAMPK expression followed by fumarate accumulation, increased TGF-&#946; expression, reduced PGC-1&#945; expression, and downregulation of methylation and hydroxymethylation of mitochondrial DNA. The sustained decrease of uric acid clearance in treated diabetes may support the prolonged kidney biochemical alterations observed after tight glycemic control, and this regulation is likely mediated by the sustained decrease of AMPK activity and the induction of inflammation. This work proposes the first consideration of the possible role of hyperuricemia and the underlying biochemical changes as part of metabolic memory in diabetic nephropathy.

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