Tang, Walfred. / "November 2011." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 151-165). / Abstracts in English and Chinese. / Title Page --- p.i / Thesis/Assessment Committee (English) --- p.ii / Acknowledgements --- p.iii / Table of Content --- p.iv / List of Figures --- p.ix / List of Graphs --- p.xi / List of Tables --- p.xiv / Abbreviations --- p.xviii / Abstract (English) --- p.xx / Abstract (Chinese) --- p.xxii / Chapter Chapter 1: --- General Introduction / Chapter 1.1 --- Renal Development --- p.2 / Chapter 1.1.1 --- The three embryonic excretory systems --- p.2 / Chapter 1.1.1.1 --- Pronephros and mesonephros --- p.2 / Chapter 1.1.1.2 --- Metanephros --- p.4 / Chapter 1.1.2 --- Renal malformations --- p.6 / Chapter 1.1.2.1 --- Causes of renal malformations --- p.8 / Chapter 1.1.2.1.1 --- Physical obstruction --- p.9 / Chapter 1.1.2.1.2 --- Mutation --- p.9 / Chapter 1.1.2.1.3 --- Environmental insults --- p.10 / Chapter 1.2 --- Retinoic Acid --- p.11 / Chapter 1.2.1 --- "Retinoic acid synthesis, signaling and degradation in the Embryo" --- p.12 / Chapter 1.2.2 --- Retinoic acid and embryonic development --- p.14 / Chapter 1.2.2.1 --- Retinoic acid and renal development --- p.15 / Chapter 1.2.3 --- Retinoic acid teratogenicity --- p.17 / Chapter 1.2.3.1 --- Retinoic acid teratogenic mechanism --- p.18 / Chapter 1.2.3.2 --- Retinoic acid-induced renal agenesis mouse model --- p.21 / Chapter 1.2.4 --- Induction of RA deficiency --- p.24 / Chapter 1.3 --- Strategy of the Thesis --- p.28 / Chapter Chapter 2: --- General Materials and Methods / Chapter 2.1 --- Mouse Maintenance and Mating Method --- p.31 / Chapter 2.2 --- Bisdiamine Preparation --- p.32 / Chapter 2.3 --- All-trans Retinoic Acid Preparation --- p.32 / Chapter 2.4 --- Embryo Dissection --- p.32 / Chapter 2.5 --- Real-time Quantitative Reverse Transcription- Polymerase Chain Reaction (RT-PCR) --- p.33 / Chapter 2.5.1 --- Sample collection --- p.33 / Chapter 2.5.2 --- Total RNA extraction --- p.33 / Chapter 2.5.3 --- Reverse transcription --- p.34 / Chapter 2.5.4 --- Polymerase chain reaction --- p.35 / Chapter 2.5.5 --- Preparation of DNA standards --- p.36 / Chapter 2.6 --- Terminal Deoxynucleotidyl Transferase-mediated dUTP Nick-end Labeling (TUNEL) Staining --- p.38 / Chapter 2.6.1 --- "Fixation, dehydration and embedding" --- p.38 / Chapter 2.6.2 --- Microtome sectioning --- p.39 / Chapter 2.6.3 --- TUNEL staining --- p.39 / Chapter Chapter 3: --- Induction of Renal Malformations by Bisdiamine via RA Deficien --- p.cy / Chapter 3.1 --- Introduction --- p.43 / Chapter 3.1.1 --- Time and dose responses to bisdiamine-induced renal malformations --- p.43 / Chapter 3.1.2 --- Methods to detect endogenous RA in embryonic tissues --- p.44 / Chapter 3.2 --- Experimental Design --- p.46 / Chapter 3.3 --- Materials and Methods --- p.48 / Chapter 3.3.1 --- Time and dose responses to bisdiamine administration --- p.48 / Chapter 3.3.2 --- Quantification of RA and retinol content in whole embryo by high pressure liquid chromatography (HPLC) --- p.49 / Chapter 3.3.2.1 --- Bisdiamine injection and sample collection --- p.49 / Chapter 3.3.2.2 --- Chromatographic system --- p.50 / Chapter 3.3.2.3 --- Preparation of standards --- p.50 / Chapter 3.3.2.4 --- Extraction of embryo samples --- p.51 / Chapter 3.3.2.5 --- Conditions of HPLC --- p.52 / Chapter 3.3.2.6 --- Recovery of sample --- p.53 / Chapter 3.3.2.7 --- Bradford protein assay --- p.53 / Chapter 3.3.3 --- X-gal staining of RARE-hsp-lacZ embryos --- p.54 / Chapter 3.3.4 --- Quantification of RA content in metanephroi by the RA-responsive cell line --- p.55 / Chapter 3.3.4.1 --- Bisdiamine injection and sample collection --- p.55 / Chapter 3.3.4.2 --- Maintenance of the RA-responsive cell line --- p.56 / Chapter 3.3.4.3 --- Seeding of cells and addition of samples --- p.57 / Chapter 3.3.4.4 --- X-gal staining --- p.58 / Chapter 3.3.5 --- TUNEL staining --- p.59 / Chapter 3.3.6 --- Real-time quantitative RT-PCR --- p.60 / Chapter 3.3.7 --- Statistical analysis --- p.61 / Chapter 3.4 --- Results --- p.63 / Chapter 3.4.1 --- Time response to bisdiamine treatment --- p.63 / Chapter 3.4.1.1 --- Bisdiamine administration increased resorption and affected various growth parameters of the fetuses --- p.64 / Chapter 3.4.1.2 --- Bisdiamine administration resulted in renal malformations --- p.68 / Chapter 3.4.1.3 --- Bisdiamine administration resulted in non-renal malformations --- p.71 / Chapter 3.4.2 --- Dose response to bisdiamine treatment --- p.76 / Chapter 3.4.2.1 --- Dose response of resorption and various growth parameters --- p.77 / Chapter 3.4.2.2 --- Dose response to bisdiamine in inducing renal malformations --- p.80 / Chapter 3.4.2.3 --- Dose response to non-renal malformations --- p.83 / Chapter 3.4.3 --- RA deficiency induced by bisdiamine --- p.88 / Chapter 3.4.3.1 --- Comparison of endogenous RA and retinol levels in control and bisdiamine-treated whole embryos at different time points after treatment --- p.88 / Chapter 3.4.3.2 --- Comparison of RA signaling patterns in control and bisdiamine-treated embryos at different time points after treatment --- p.90 / Chapter 3.4.3.3 --- Comparison of endogenous RA levels in control and bisdiamine-treated metanephroi at different time points after treatment --- p.93 / Chapter 3.4.4 --- Increase in the number of apoptotic nuclei in the metanephros after bisdiamine treatment --- p.95 / Chapter 3.4.5 --- Alteration of genes expression in the metanephros after bisdiamine treatment --- p.96 / Chapter 3.5 --- Discussion --- p.99 / Figures / Graphs / Chapter Chapter 4: --- Rescuing Bisdiamine-treated Metanephroi by In Vitro Supplementation with Low Concentrations of RA / Chapter 4.1 --- Introduction --- p.107 / Chapter 4.1.1 --- Embryonic kidney culture --- p.107 / Chapter 4.1.2 --- In vitro culture of the RA-treated metanephros --- p.108 / Chapter 4.1.3 --- Effect of exogenous retinoic acid on in vitro development of metanephros --- p.109 / Chapter 4.2 --- Experimental Design --- p.111 / Chapter 4.3 --- Materials and Methods --- p.113 / Chapter 4.3.1 --- Supplementation of low concentrations of RA to metanephric explant culture --- p.113 / Chapter 4.3.1.1 --- Preparation of culture medium supplemented with low concentrations of RA --- p.113 / Chapter 4.3.1.2 --- Metanephric explant culture --- p.114 / Chapter 4.3.2 --- Whole-mount immunohistochemical staining of ureteric epithelium and nephric tubules in metanephric explants --- p.115 / Chapter 4.3.3 --- TUNEL staining of metanephric explants --- p.116 / Chapter 4.3.4 --- Real-time quantitative RT-PCR --- p.117 / Chapter 4.3.5 --- Statistical analysis --- p.117 / Chapter 4.4 --- Results --- p.119 / Chapter 4.4.1 --- Rescue of bisdiamine-treated metanephric explants by in vitro culture in medium supplemented with low concentrations of RA --- p.119 / Chapter 4.4.1.1 --- Assessment of metanephric development under various concentrations of RA by morphological grading of UB tips at different day of culture --- p.119 / Chapter 4.4.1.2 --- Effect of various concentrations of RA on the number of UB tips and nephric tubules in metanephric explants at day 6 of culture --- p.126 / Chapter 4.4.2 --- Effect of RA supplementation on apoptosis in bisdiamine-treated metanephric explants --- p.131 / Chapter 4.4.3 --- Effect of RA supplementation on genes expression in bisdiamine-treated metanephric explants --- p.133 / Chapter 4.5 --- Discussion --- p.136 / Figures / Graphs / Chapter Chapter 5: --- Conclusion and Future Perspectives --- p.141 / References --- p.150

糖調節蛋白78 (Glucose-regulated protein 78),也稱之Bip,是70kDa熱休克蛋白家族成员之一。已有的研究表明，Bip 是一個具有多功能的蛋白，參與眾多的生物調控過程，包括蛋白折疊，調節鈣平衡，以及作為內質網緊張（ER stress) 的感應器。有研究表明，Bip可以在細胞膜上定位，作為Nodal信號通路的一個輔助受體發揮作用。大量的研究表明，Bip在疾病和代謝方面也發揮重要作用。它參與胰島素的生物合成，並可以提高長期高血糖下β細胞的功能。同時具有抗細胞凋亡的作用。然而Bip在胚胎髮育中的生物功能卻知之甚少。 / 高等脊椎動物腎臟發育中經歷形成3種腎臟形式：前腎，中腎和後腎。腎單位是這3種形式的基本結構和功能單位。在兩棲類，前腎在胚胎時期發揮作用，在胚胎的兩側各只有一個腎單位。這使得爪蟾成為前腎研究的一個非常好的模型。 / 在此項研究中，我們採用非洲爪蛙作為動物模型來研究Bip在胚胎髮育過程中，尤其是在前腎發育中的生物功能。Bip是一個母性因子，在尾芽期，Bip 表達在粘液腺，前腎，肝以及耳囊。 Bip在前腎清晰明確的表達，表明Bip可能在前腎的發育中發揮作用。我們利用BipMO來進行敲低功能實驗，免疫印記顯示BipMO能阻斷帶Flag標記Bip的翻譯。通過原位雜交技術檢測前腎的不同標記基因的表達發現，敲低Bip抑制前腎的形成，表明Bip的正常表達是前腎發育所必須的。 / 為了研究Bip調節前腎的發育的分子機制， 我們使用Affmetrix基因芯片分析在Bip敲低情況下的不同時期胚胎中基因的表達譜，發現在Bip敲低表達的胚胎中，視黃酸信號通路的一些重要的組分的表達受到抑制。爪蛙胚胎原腸胚的動物帽細胞具有多能性， 使用激活素和視黃酸一同處理動物帽細胞可以誘導其分化成為原腎組織。在此體外分化體系中敲低Bip表達，前腎標記基因表達降低，顯示在這一體外系統中前腎的分化受到抑制。該實驗結果與體內實驗結果一致。在體外培養的HEK293T細胞中敲低Bip，抑制視黃酸處理後視黃酸信號通路螢光素報告的活性。 lhx1是前腎發育早期表達標記之一，對於前腎原基的初始化具有重要的作用，同是它也是視黃酸信號通路的靶基因。共同註射BipMO和lhx1表明，前腎的異常可以明顯降低，顯示lhx1可以部份拯救由於Bip缺失所造成的腎臟發育缺陷。該實驗表明Bip通過調節視黃酸信號通路，來調控lhx1的表達前腎的形成。我們進一不發現，敲低Bip後，前腎異常形成的區域內，細胞凋亡增加，增殖減少。該結果在細胞水平上解釋了Bip敲低表達時前腎形成異常的一個原因。 / 综述所述，Bip正確表達对胚胎前肾的发育極為重要。它胚胎发育过程中通过視黃酸信号通路調控lhx1的表達，從而对前肾的形成发挥重要作用。 / Glucose-regulated protein 78 (Grp78), also known as Bip, belongs to heat shock protein 70kDa family. It has been implicated in various biological processes including protein folding, regulation of calcium homeostasis, and serving as a sensor of ER (Endoplasmic Reticulum) stress. Moreover, it can localize in cell membrane, acting as co-receptor of nodal signaling. It is essential for insulin biosynthesis. In addition, Bip plays important roles in a number of diseases. For example, BIP can improve β-cell function in the prolonged hyperglycemia. Knockdown of BIP in β-cell can induce apoptosis. However, little is known about its function during embryonic development. / In high vertebrate, three sets of nephric forms develop successively during embryonic kidney development. They are pronephros, mesonephros, and metanephros. Nephron is the basic structural and functional unit of all these three forms. In amphibian, the pronephros performs function at the embryonic stages, which has only one nephron on either side of the body. It makes Xenopus a very good model for pronephros study. / In this study, we took advantage of Xenopus leavis as an animal model to investigate Bip function during embryonic development, especially its role in pronephros development. We first examined the expression of Bip in developing embryos. Whole mount in situ hybridization showed that Bip was expressed in the cement gland, pronephros, liver and ear vesicle during tailbud stages. It was expressed in the pronephros strongly and clearly which suggested that Bip might play roles in pronephros development. We performed loss-of-function experiment by using morpholino oligonucleotide (MO) knock down translation of endogenous Bip expression. Depletion of Bip impaired formation of pronephros revealed by reduction expression of different pronephros maker genes. The pluripotent animal caps can differentiate into pronephros tissue when treated with activin and all-trans retinoic acid (atRA) in vitro kidney induction assay. In line with our in vivo observation, knockdown of Bip inhibited pronephros differentiation that can normally achieved by combined effects of activin and atRA in animal cap assay. / In order to investigate the molecular mechanisms as how Bip regulated pronephros development, we performed Affymetrix DNA microarray assay to generate gene expression profile in Bip morphants. We found that some components of RA signaling were inhibited when Bip was knockdown. Moreover, knockdown of Bip caused reduction of RA target genes expression after treatment with RA. Consistent with above observations, luciferase activities of RA signaling reporter was reduced in HEK293T cells when BIP expression was depleted by RNAi. lhx1 is one of RA target genes and has been implicated playing essential roles in pronephros development. The inhibition of pronephros formation induced by Bip depletion can be partially rescued by co-overpression, suggesting 1) lhx1 is downstream of Bip in the regulatory network of pronephros formation; and 2) Bip regulates pronephros formation through RA signaling via lhx1. We also found increased apoptosis and decreased cell proliferation at pronephros-forming region in Bip morphants. That could explain the reason of pronephros malformation when Bip is downregulated. / Taken together, Bip is essential for pronephros development. It functions through RA signaling during the complex developmental processes. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Shi, Weili. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 125-143). / Abstracts also in Chinese.

A poluição atmosférica é um importante fator de risco à saúde humana, com maior vulnerabilidade em pessoas com doenças pré-existentes, idosos, crianças e fetos. A teoria da origem desenvolvimentista da saúde e doença se baseia em evidências que alterações no desenvolvimento fetal que podem levar a prematuridade, baixo peso ao nascer e predispor ao surgimento de síndrome metabólica, hipertensão e doenças renais na idade adulta. Há evidências também que alterações do ambiente intrauterino na gestação afetam o número de néfrons ao nascimento, o que predispõe à hipertensão na idade adulta. Estudos experimentais prévios comprovam que o ar de São Paulo apresenta uma concentração de poluentes capaz de desencadear, além de lesões cardio-respiratórias, alterações reprodutivas como baixo peso ao nascer e prematuridade. O objetivo deste estudo foi avaliar de maneira objetiva se a exposição aos níveis ambientais de poluição atmosférica no período gestacional tem o potencial de promover alterações de volume renal e número de glomérulos ao nascimento, o que, com base na teoria da origem fetal das doenças, poderia ser um fator predisponente para doenças renais e hipertensão no adulto. Para tanto, neste estudo, foram estudados rins fetos de camundongos Balb/c no 18º dia pós-concepção, expostos aos níveis ambientais de poluição do ar em São Paulo, em duas câmaras de exposição uma recebendo ar filtrado (F) e outra ar não filtrado (P). Os rins dos fetos foram avaliados morfologicamente por métodos estereológicos para estimativa do volume renal total e de cada compartimento (córtex e medula) e número de néfrons. A concentração do material particulado na câmara filtrada foi significantemente menor (71%, p<0.001) que na câmara não filtrada. O peso fetal e dos rins foi 30% menor no grupo NF em relação ao grupo F (p=0.007 e p=0,0112 respectivamente). iv Doutorado Nilsa Regina Damaceno-Rodrigues 2012 O córtex e a medula renais dos fetos do grupo NF apresentaram redução de volume: córtex: 4,46±0,55 x 2,44±0,79 (p=0,0003); medula: 2,35±0,43 x 1,24±0,61 (p=0,0034). O número absoluto de néfrons no rim dos fetos NF (3301,0±1720,8) foi significantemente menor (p=0,0082) que nos fetos F (7199,5±2023,5). Estes dados mostram que a exposição pré-natal aos níveis ambientais de poluição em São Paulo provoca uma alteração no desenvolvimento renal, que pode levar à doenças no adulto / Air pollution is an important risk factor to human health, with greater vulnerability in people with pre-existing diseases, elderly, children and fetuses. The theory of developmental origins of health and illness proposes that changes in fetal development that can lead to prematurity, low birth weight and predisposition to chronic diseases in adulthood. There is also evidence that changes in the intrauterine environment during pregnancy affect the number of nephrons at birth, which predisposes to hypertension in adulthood. Previous experimental studies show that the air of Sao Paulo has a concentration of pollutants that can trigger cardio-respiratory lesions and reproductive hindrances as low birth weight and prematurity. Our proposal was to evaluate objectively whether exposure to ambient levels of air pollution during pregnancy has the potential to promote changes in renal volume and number of glomeruli at birth, which could be a predisposing factor for adult renal illness and hypertension based on the theory of fetal origin of the disease. Therefore, in this study, we used kidneys of fetal Balb/c mice on day 18 post-conception (dpc), exposed to ambient levels of air pollution in Sao Paulo in two exposure chambers: one receiving filtered air (F) and other non-filtered air (P). The kidneys of the fetuses were morphologically evaluated by stereological methods for estimation of total renal volume and the volume of each compartment (cortex and medulla) and the number of nephrons. The concentration of particulate matter in the filtered chamber was significantly lower (71%, p<0.001) than in the unfiltered chamber. Fetal weight and kidney weight were 30% lower in the unfiltered chamber (p=0.007 and p=0.0112 respectively). The renal cortex and medulla of exposed fetuses showed volume reduction; cortex: 4.46 ± 0.55 x 2.44 ± Doutorado Nilsa Regina Damaceno-Rodrigues 2012 0.79 (p=0.0003); medulla: 2.35 ± 0.43 x 1.24 ± 0.61 (p=0.0034). The absolute number of nephrons in the kidney of exposed fetuses (3301,0±1720,8) was significantly lower (p=0.0082) when compared to the filtered air group (7199,5±2023,5). These data show that pre-natal exposure to ambient levels of air pollution in Sao Paulo entails changes in the development of the kidney, that can lead to illness in adult age.

A poluição atmosférica é um importante fator de risco à saúde humana, com maior vulnerabilidade em pessoas com doenças pré-existentes, idosos, crianças e fetos. A teoria da origem desenvolvimentista da saúde e doença se baseia em evidências que alterações no desenvolvimento fetal que podem levar a prematuridade, baixo peso ao nascer e predispor ao surgimento de síndrome metabólica, hipertensão e doenças renais na idade adulta. Há evidências também que alterações do ambiente intrauterino na gestação afetam o número de néfrons ao nascimento, o que predispõe à hipertensão na idade adulta. Estudos experimentais prévios comprovam que o ar de São Paulo apresenta uma concentração de poluentes capaz de desencadear, além de lesões cardio-respiratórias, alterações reprodutivas como baixo peso ao nascer e prematuridade. O objetivo deste estudo foi avaliar de maneira objetiva se a exposição aos níveis ambientais de poluição atmosférica no período gestacional tem o potencial de promover alterações de volume renal e número de glomérulos ao nascimento, o que, com base na teoria da origem fetal das doenças, poderia ser um fator predisponente para doenças renais e hipertensão no adulto. Para tanto, neste estudo, foram estudados rins fetos de camundongos Balb/c no 18º dia pós-concepção, expostos aos níveis ambientais de poluição do ar em São Paulo, em duas câmaras de exposição uma recebendo ar filtrado (F) e outra ar não filtrado (P). Os rins dos fetos foram avaliados morfologicamente por métodos estereológicos para estimativa do volume renal total e de cada compartimento (córtex e medula) e número de néfrons. A concentração do material particulado na câmara filtrada foi significantemente menor (71%, p<0.001) que na câmara não filtrada. O peso fetal e dos rins foi 30% menor no grupo NF em relação ao grupo F (p=0.007 e p=0,0112 respectivamente). iv Doutorado Nilsa Regina Damaceno-Rodrigues 2012 O córtex e a medula renais dos fetos do grupo NF apresentaram redução de volume: córtex: 4,46±0,55 x 2,44±0,79 (p=0,0003); medula: 2,35±0,43 x 1,24±0,61 (p=0,0034). O número absoluto de néfrons no rim dos fetos NF (3301,0±1720,8) foi significantemente menor (p=0,0082) que nos fetos F (7199,5±2023,5). Estes dados mostram que a exposição pré-natal aos níveis ambientais de poluição em São Paulo provoca uma alteração no desenvolvimento renal, que pode levar à doenças no adulto / Air pollution is an important risk factor to human health, with greater vulnerability in people with pre-existing diseases, elderly, children and fetuses. The theory of developmental origins of health and illness proposes that changes in fetal development that can lead to prematurity, low birth weight and predisposition to chronic diseases in adulthood. There is also evidence that changes in the intrauterine environment during pregnancy affect the number of nephrons at birth, which predisposes to hypertension in adulthood. Previous experimental studies show that the air of Sao Paulo has a concentration of pollutants that can trigger cardio-respiratory lesions and reproductive hindrances as low birth weight and prematurity. Our proposal was to evaluate objectively whether exposure to ambient levels of air pollution during pregnancy has the potential to promote changes in renal volume and number of glomeruli at birth, which could be a predisposing factor for adult renal illness and hypertension based on the theory of fetal origin of the disease. Therefore, in this study, we used kidneys of fetal Balb/c mice on day 18 post-conception (dpc), exposed to ambient levels of air pollution in Sao Paulo in two exposure chambers: one receiving filtered air (F) and other non-filtered air (P). The kidneys of the fetuses were morphologically evaluated by stereological methods for estimation of total renal volume and the volume of each compartment (cortex and medulla) and the number of nephrons. The concentration of particulate matter in the filtered chamber was significantly lower (71%, p<0.001) than in the unfiltered chamber. Fetal weight and kidney weight were 30% lower in the unfiltered chamber (p=0.007 and p=0.0112 respectively). The renal cortex and medulla of exposed fetuses showed volume reduction; cortex: 4.46 ± 0.55 x 2.44 ± Doutorado Nilsa Regina Damaceno-Rodrigues 2012 0.79 (p=0.0003); medulla: 2.35 ± 0.43 x 1.24 ± 0.61 (p=0.0034). The absolute number of nephrons in the kidney of exposed fetuses (3301,0±1720,8) was significantly lower (p=0.0082) when compared to the filtered air group (7199,5±2023,5). These data show that pre-natal exposure to ambient levels of air pollution in Sao Paulo entails changes in the development of the kidney, that can lead to illness in adult age.