Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Univ., 2004. / Härtill 4 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2004. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.

Thesis (Ph.D. in Pharmaceutical Sciences) -- University of Colorado Denver, 2008. / Typescript. Includes bibliographical references (leaves 209-236). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;

A nefropatia induzida por adriamicina (ADR) em ratos é um dos modelos experimentais mais utilizados para o estudo desenvolvimento da doença renal progressiva. Uma dose única deste quimioterápico induz a proteinúria progressiva e irreversível que progride para glomeruloesclerose segmental e focal, com fusão dos processos podais e lesões tubulointersticiais. A lesão das células endoteliais glomerulares precede as alterações dos podócitos na nefropatia induzida pela ADR. A atividade física regular melhora as funções cardíacas e renais em pacientes e animais com doença renal progressiva e pode reduzir ou retardar a progressão da lesão renal. Este estudo avaliou o efeito do treinamento físico prévio na evolução da lesão renal induzida por ADR e a sua relação com o processo inflamatório, a função endotelial e angiogênese. Ratos Wistar submetidos ou não ao treinamento físico receberam ADR (2,5 mg/kg, e.v) ou solução salina fisiológica (SAL). Amostras de sangue e urina foram coletadas 60 dias após as injeções para avaliação da função renal e os rins removidos para estudos histológicos, imuno-histoquímicos, Western blot e de ELISA. Amostras de urina de 24 h, obtidas 7, 30 e 60 dias após a administração de ADR ou SAL, foram utilizadas para avaliação da albuminúria. Os ratos tratados com ADR apresentaram albuminúria progressiva, elevação dos níveis plasmáticos de creatinina e queda da taxa de filtração glomerular (TFG), lesão de podócitos, expansão da área mesangial, alargamento da área intersticial relativa no córtex renal, infiltração de macrófagos, aumento dos níveis de interleucina (IL)-1?, elevação dos níveis urinários do fator de transformação do crescimento ? (TGF-?) e dos níveis urinários de proteína quimiotática de monócitos 1 (MCP-1), diminuição de marcação de aminopeptidase P (marcador de células endoteliais) nos glomérulos e perda de capilares peritubulares corticais, que estavam associados com reduções das expressões do fator de crescimento endotelial vascular (VEGF) e da óxido nítrico sintase endotelial (eNOS) no córtex renal desses animais. Estas alterações foram menos intensas nos ratos que realizaram treinamento físico prévio ao tratamento com ADR. Em conclusão, o pré-condicionamento físico reduziu as lesões renais induzidas pela ADR. Este efeito esteve associado com as reduções do processo inflamatório, das lesões endoteliais e das alterações de fatores relacionados com o processo de angiogênese (VEGF e eNOS) no córtex renal. / Adriamycin (ADR)-induced nephropathy is one of the most experimental models of progressive kidney disease in rats. A single dose of this drug induces progressive and irreversible proteinuria that progresses to focal segmental glomerulosclerosis and tubulointerstitial lesions. The lesion of glomerular endothelial cells precedes the podocyte damage in nephropathy induced by ADR. Regular physical activity improves cardiac and renal functions in patients and animals with progressive renal disease and may reduce or delay the progress of impaired renal function. This study evaluated the effect of previous physical training in renal damage induced by ADR and the role of inflammation, endothelial lesions and angiogenesis in this process. Male Wistar rats submitted or not to previous physical training received ADR (2.5 mg/kg, i.v.) or physiological saline (SAL). Urine and plasma samples were collect 60 days after the injection in order to evaluated the renal function. The kidneys were removed for histological, immunohistochemical, Western blot and ELISA analysis. Twenty-four-hour urine samples were collected to dose albuminuria 7, 30 and 60 days after ADR or SAL injection. ADR-treated rats presented progressive albuminuria, increases in plasma creatinine levels, decreasing glomerular filtration rate (GFR), podocyte damage, mesangial expansion, enlargement of the tubular interstitial relative area of renal cortex, macrophage infiltration, higher interleukin (IL)- 1? levels in renal tissue, urinary transforming growth factor ? (TGF-?) and urinary monocyte chemoattractant protein (MCP)-1, reduction of aminopeptidase P (endothelial cell marker) in the glomeruli and cortical peritubular capillary number. Those were associated with reduction in vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS) expressions in renal cortex. Those alterations were less intense in the animals undergone previous exercise training. In conclusion, physical training prior to ADR injection reduced the renal damage induced by this drug. This effect was related with the reduction of the inflammatory process, endothelial lesions and with the decrease in alterations of factors related to the process of angiogenesis (VEGF and eNOS) in renal cortex.

Suite à une lésion, la réparation d’un tissu à l’identique est l’objectif clinique recherché. Ainsi un hémostatique, au-delà de sa capacité à arrêter un saignement, se doit au minimum de ne pas être délétère pour la réparation tissulaire. Or, malgré une efficacité hémostatique démontrée Tachosil® et Surgicel®, couramment utilisés en chirurgie, peuvent générer en raison de leur persistance in situ associée à une résorption incomplète, des évènements indésirables graves (nécrose, hypersensibilité, allergie, sténose, complication thromboembolique, sepsis…). Dans ce contexte, nous avons étudié les effets d’un nouvel hémostatique non implantable, HÉMO-IONIC®, sur toutes les étapes de la réparation tissulaire : de l’hémostase à la phase de maturation. HÉMO-IONIC®, Tachosil® et Surgicel® ont été évalués in vitro sur la fonctionnalité des Endothelial Colony Forming Cells (ECFCs) ; et in vivo dans deux modèles murins, un modèle d’hémostase et un de réparation tissulaire. Grâce à ces travaux, constituant une approche originale de l’évaluation des hémostatiques, nous avons démontré que seul HÉMO-IONIC®, en plus d’être un hémostatique efficace, maintient l’ensemble des propriétés fonctionnelles des cellules endothéliales et agit, à plus long terme, positivement sur l’ensemble des étapes de la réparation tissulaire. Ces données ouvrent des perspectives particulièrement intéressantes, notamment dans la prise en charge des brûlures nécessitant la restitution d’un tissu cutané de qualité (souple et élastique). Ainsi, l’association d’HÉMO-IONIC® à l’expertise du Service de Santé des Armées (SSA) dans l’utilisation des cellules stromales mésenchymateuses comme Médicament de Thérapie Innovante (MTI) pourrait représenter, dans la prise en charge des brûlures, une avancée thérapeutique en améliorant les résultats fonctionnels et esthétiques. / After an injury, the clinical objective is to faithfully repair tissues. Thus, a hemostatic agent, beyond its ability to stop bleeding, must at least not be deleterious for tissue repair. However, despite proven hemostatic efficacy, Tachosil® and Surgicel®, which are commonly used in surgery, can lead to serious adverse events (necrosis, hypersensitivity, allergy, stenosis, thromboembolic complication, sepsis…) due to their in situ persistence associated with their incomplete resorption. In this context, we studied the effects of a new non-implantable hemostatic agent, HÉMO-IONIC®, on all stages of tissue repair : from hemostasis to maturation phase. The effects of HÉMO-IONIC®, Tachosil® and Surgicel® were assessed in vitro on Endothelial Colony Forming Cell function (ECFCs) and in vivo in two mouse models of hemostasis and tissue repair. Using an original approach to the assessment of hemostatic agents, we showed that only HÉMO-IONIC®, in addition to being effective, maintained all the functional properties of endothelial cells and acted positively on all stages of tissue repair in the longer term. These data open up very interesting perspectives, in particular in the management of burns where restoring a quality cutaneous tissue (supple and elastic) is required. Thus, in burn management, combining HÉMO-IONIC® with the French Defence Health service expertise in the use of mesenchymatous stromal cells as an advanced therapy medicinal product could be a therapeutic advance by improving the functional and esthetic outcomes.

Preclinical testing is necessary to investigate the safety and efficacy of novel therapeutics before moving to clinical trials, yet approximately 90% of these therapies fail once tested in humans. This has led to increased interest in developing robust preclinical models that accurately mimic the complex human in vivo physiology. Microfluidic devices that can introduce dynamic conditions to 3D cell/organoid cultures, also known as tissue-on-a-chip, have emerged as physiologically relevant in vitro preclinical models that can achieve high throughput screening of therapeutics. The research presented here aimed to develop an angiogenic environment within a novel microfluidic device to stimulate formation of endothelial networks that will eventually be integrated into a vascularized tumor model for screening chemotherapeutics. The novel microfluidic devices were fabricated using photolithography to create a patterned mold, casting polydimethylsiloxane (PDMS) over the mold, and bonding patterned PDMS to a glass slide. Three sets of experiments were then conducted, with each introducing different angiogenic stimuli to human umbilical vein endothelial cells (HUVECs) co-cultured with human dermal fibroblasts (HDFs) within the devices. The first set of experiments sought to develop a standard protocol for plating human cells in the novel microfluidic device and to investigate if the mechanism of nutrient transport and interstitial flow would induce an angiogenic response resulting in endothelial network formation. A working protocol was developed but it was determined that further development of an angiogenic environment within the device was necessary to stimulate endothelial network formation. The second set of experiments investigated if seeding HUVECs in a peripheral channel of the device and introducing a concentration gradient of vascular endothelial growth factor (VEGF) would stimulate endothelial network formation directed by a growth factor gradient, similar to angiogenesis in vivo. This was repeated under hypoxic conditions to more accurately mimic the in vivo angiogenic environment, but significant endothelial network formation was not observed and seeding of HUVECs in the peripheral channel presented no perceptible improvements. The final set of experiments investigated if v returning HUVECs to the center chamber in local co-culture with HDFs and exposing devices to hypoxic conditions would provide the necessary angiogenic environment to stimulate endothelial network formation within the microfluidic device. Lack of quantifiable endothelial network formation in the final set of experiments led to an analysis of 3D HUVEC colony formation, however, no statistically significant trends were discovered. Even though no significant differences were found, these experiments succeeded in developing a protocol for plating human cells in the novel microfluidic device that can be translated to the tumor side of the Microphysiological Systems lab. From these experiments we can also conclude that co-cultures of HUVECs and HDFs can survive and form into colonies within the novel microfluidic device but additional angiogenic stimuli are necessary to develop robust endothelial networks. Based on the current literature and knowledge gained throughout the experiments presented here, several suggestions are presented to potentially stimulate angiogenesis and develop endothelial networks in the device such as increasing cell densities, varying length of incubation, introducing mediators of angiogenesis like nitric oxide, and addition of tumor cells.

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