以客觀存在之腎臟損害和功能異常的臨床表現為診斷依據的腎臟疾病，業已成為全世界所共同面臨的危害人類健康的一項主要健康問題。現今，人群中有超過十分之一的人患有慢性腎臟疾病（CKD）, 該病的患病率不亞於糖尿病 (James et al., 2010)。慢性腎髒病是一種難以治癒的疾病。儘管存在有效的治療方法，但在全世界範圍內，慢性腎髒病仍舊是導致終末期腎臟疾病和死亡的首要原因。據2010年全球疾病負擔的研究報導 (Lozano et al., 2013)，在引起全球死亡總數原因列表中，慢性腎髒病由1990年的第27位（年齡標準化的每100 000人的年死亡率為15.7）躍升至2010年的第18位（每100 000人的年死亡率為16.3）。慢性腎髒病的攀升趨勢僅次於HIV和AIDS。這種狀況已經引起高度關注，應對措施的實施刻不容緩！因此，迫切需要慢性腎髒病早期診斷和治療的有效方案。 / 纖維化是慢性腎髒病這一以終末期腎髒病（ESRD）為結局的疾病腎臟損傷和進展的主要病理特徵。現已確立转化生长因子β/Smads 信号蛋白（TGF-β/Smad）在腎臟纖維化發病機制中具有主要的作用。在過去近20年對於转化生长因子β/Smads 信号蛋白在慢性腎髒病發病機制中的作用研究揭示：Smad3在腎臟纖維化中起致病作用，而Smad2和Smad7具保護作用。鑒於转化生长因子β/Smads 信号蛋白在免疫調節中也發揮關鍵作用，直接針對转化生长因子β/Smads 信号蛋白的干預方案可能引起免疫損傷的副作用。因而，針對转化生长因子β/Smads 信号蛋白特異性下游靶目標的療法是對抗慢性腎髒病更好的選擇。 / 自首個微小核糖核酸的發現至今，已歷經20年。微小核糖核酸在基因表达的转录后起著重要調節作用。現已明確，在人類疾病包括腎臟病的發生和/或進展中存在微小核糖核酸的表達或功能的失調。最近的研究明確的表明，微小核糖核酸與腎臟疾病的發病機制密切相關。另外，已有確鑿的證據顯示，一些微小核糖核酸正是转化生长因子β/Smads信号蛋白的特異性下游。並且我們發現，不僅在转化生长因子β和血管緊張素II誘導的體外纖維化反應中，而且在小鼠體內梗阻性和高血壓性腎病模型中，微小核糖核酸-433-Azin1軸不但在腎臟纖維化中起重要作用，並且和转化生长因子β/Smad3信号蛋白密切相關。據重要意義的是，藉助安全、有效的超聲微泡介導的基因轉染方法，通過逆轉失調的微小核糖核酸-433-Azin1軸，有效的抑制了小鼠腎臟疾病的進展、腎組織的損傷并減少了蛋白尿的排泄。因此，微小核糖核酸-433-Azin1軸不但可以作為慢性腎臟病早期診斷的生物學標記，也能夠成為遏制甚至逆轉慢性腎髒病的治療靶點。 / 近年來，從基礎到臨床旨在預防和治療慢性腎髒病的研究已取得碩果累累。基於以转化生长因子β/Smad3信号蛋白特異性微小核糖核酸為把目標的治療策略，預見了遏制慢性腎髒病治療的未來希望。然而， 消除慢性腎髒病這一世界性的人類健康威脅，仍需付諸長期不懈的努力。 / Kidney disease is diagnosed with objective clinic manifestation of kidney damage and renal dysfunction has been recognized as a major global health burden. Nowadays, more than one out of ten people have chronic kidney disease (CKD) and the overall prevalence is not less than that of diabetes (James et al., 2010). CKD is a kind of persistent ailment. In spite of the availability of medical treatments, CKD continues to be a leading cause of end stage of renal disease (ESRD) and death worldwide. Reported in the 2010 Global Burden of Disease study (Lozano et al., 2013), CKD was ranked from 27th in 1990 (age-standardised annual death rate of 15.7 per 100 000) and rose to 18th in 2010 (annual death rate 16.3 per 100 000) in the list of causes of total number of global deaths. The growing momentum of CKD was just second to that for HIV and AIDS. This situation has claimed our serious attention and the prompt action is imperative. Thus, effective early diagnosis biomarker and treatment of CKD are urgent needed. / Fibrosis is the key feature during renal lesion formation and progression in CKD which will be ended in ESRD eventually. It has been established that Transforming growth factor β/Combination of the Drosophila protein "Mothers against decapentaplegic" (MAD) and C. elegant protein SMA (TGF-β/Smad) signaling plays a central role in the pathogenesis of renal fibrosis. For last two decades, dissection of the critical role of TGF-β/Smad signaling in the fibrogenesis of CKD has unveiled that Smad3 plays a pathogenic but Smad2 and Smad7 play a protective role in renal fibrosis. As TGF-β/Smad signaling also plays a crucial function in immunity, targeting TGF-β/Smad signaling may cause adverse effect. Thus, targeting specific downstream of T GF-β/Smad signaling should be a better alternative to fight against CKD. / A score of years has elapsed from the first microRNA discovery. MicroRNAs are important post-transcriptional regulators of gene expression. It is now widely acknowledged that the dysregulation of microRNA expression or action underlies the onset and/or development of various human diseases including kidney disease. Recently, researches have substantial evidences that microRNAs are tightly associated with the pathogenesis of kidney disease. In addition, eye-catching tangible evidences showed that several microRNAs are specific downstream of TGF-β/Smad3 signaling. Moreover, we found that not only in TGF-β and angiotensin II induced fibrotic response in vitro, but also in mouse models of obstructive and hypertensive nephropathy, microRNA-433-Azin1 axis is vital in renal fibrosis and is closely related with TGF-β/Smad3 signaling. Last but not least, our study suggests that, using a safe, effective, ultrasound microbubble-mediated gene transfer therapeutic method can significantly halt the progression of kidney lesions and reduce renal tissue damage and the excretion of albuminuria by balancing the microRNA-433-Azin1 axis. Hence, microRNA-433-Azin1 axis may act either as biomarkers favorable early diagnosis or therapeutic targets to halt or even reverse CKD. / The bench and bedside research on preventing and managing CKD have gained fruitful results in recent decades. Therapeutic strategy against TGF-β/Smad3 specific microRNA brings us a bright future in combating against CKD. However, more endeavors are necessary to eliminate the enormous burden of CKD worldwide. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Rong. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 182-202). / Abstracts also in Chinese.

DRC é a condição que descreve alteração irreversível da função renal, desencadeando o desenvolvimento de vários sintomas neurológicos. Dentre as hipóteses estão o estresse oxidativo, a resposta inflamatória e a Klotho envolvidos na patogênese tanto da DRC quanto das lesões relacionadas à Demência Vascular. O objetivo deste trabalho é o de avaliar a ausência e presença de déficit cognitivo (CI) em pacientes com DRC em hemodiálise, bem como em modelo animal de 5/6 de ablação renal (Nx), relacionando a concentração de citocinas e klotho em soro, líquor de rato e homogenato de tecido cerebral e renal de rato. Observamos que os mediadores séricos pró- e antinflamatórios, nos indivíduos DRC e DRC-CI, não apresentaram diferença em relação aos indivíduos do grupo controle. Nos animais Nx, não encontramos correlação entre as alterações séricas de citocinas pró- e antiinflamatórias com CI. Finalmente, observamos redução dos níveis séricos da Klotho nos indivíduos do grupo DRC-CI, assim como nos animais Nx-CI quando comparados com os respectivos grupos Controle e DRC sem CI. / CKD is a condition that describes irreversible alteration of renal function and development of various neurological symptoms. Several hypotheses are described as triggering factors of cognitive impairment (CI) related to CKD, including the linked of oxidative stress, inflammation and Klotho in the pathogenesis of CKD and of injuries related to vascular dementia. The objective of this thesis is to evaluate the presence and absence of CI in patients with CKD on hemodialysis, as well as in a 5/6 renal ablation animal model, linking to citokynes and Klotho levels in plasma, brain and kidney samples and cerebrospinal fluid. Our data showed no differences in serum pro-inflammatory and anti-inflammatory mediators in CKD and CKD-CI groups when compared to the control group as well in the animal model of CKD. Our data also showed a reduction in serum levels of Klotho among individuals with CKD-CI, as well as in animals with CI associated with the animal model of CKD when compared with the respective control groups and CKD without deficit.

Atualmente, os primatas de pequeno e médio porte, em especial os sagüis, têm grande destaque em estudos experimentais, pois são usados frequentemente como modelo para estudos comparativos de várias doenças em humanos, entretanto vários aspectos básicos de sua anatomia ainda estão por serem estudados. Com esta motivação, rins de 20 Callithrix jacchus da colônia do DPZ (Centro de Primatas da Alemanha), foram utilizados para sua caracterização morfométrica macro e microscópica, onde os parâmetros relativos à mensuração anatômica, comprimento, altura, largura, peso e volume dos rins foram estabelecidos, bem como a quantificação de glomérulos e mensuração da área glomerular, com a finalidade de se comparar a influência de fatores como simetria bilateral, sexo, idade e condição sanitária, nestes parâmetros. Com base nos resultados concluiu-se que todos os parâmetros mensurados não são influenciados pelo sexo ou pela simetria. Os rins dos animais com alteração nos exames apresentaram maior tamanho (comprimento, altura e largura), peso e volume, e também, maior área glomerular que os rins dos animais sadios. Nos animais mais jovens, o número de glomérulos quantificados foi maior e a área glomerular média foi menor, que em animais mais velhos. / Currently, the primates of small and medium size, especially the marmosets, have great prominence in experimental studies, they are often used as a model for comparative studies of various diseases in humans, but several basic aspects of their anatomy are still being studied. With this motivation, the kidneys of 20 Callithrix jacchus in the colony of DPZ (German Primate Center), were used to characterize their macroscopic and microscopic morphometry, where the parameters for anatomical measurements, length, height, width, weight and volume of the kidneys were established, as well as quantification of glomeruli and measurement of glomerular area in order to compare the influence of factors such as bilateral symmetry, sex, age and health condition in these parameters. Based on the results concluded that all measured parameters are not affected by sex or by symmetry. The kidneys of animals with changes in the examinations of larger size (length, width and height), weight and volume, and also a greater area than the glomerular kidney of healthy animals. In younger animals, the number of glomeruli was higher and the mean glomerular area was smaller than in older animals.

O balanço do fluoreto (F) dentro do corpo é modulado por sua ingestão, absorção e remoção, e os rins, responsáveis pela sua excreção do organismo, são particularmente vulneráveis à toxicidade do F. Os efeitos nefrotóxicos do F envolvem mudanças estruturais marcantes nos rins, além disso, estudos proteomicos têm mostrado grandes alterações no perfil de proteínas envolvidas em pontos chave na transdução de sinal. Estes efeitos podem influenciar negativamente no transporte iônico nos rins. A vista deste fato, o transporte iônico no canal de sódio epitelial (ENaC) é limitante para a taxa de reabsorção de sódio nos rins, sendo essencial para a manutenção do equilíbrio eletrolítico e homeostase do corpo. Assim, este trabalho objetivou investigar os efeitos do F, utilizando concentrações semelhantes às que podem ser encontradas no néfron durante a fluorose dentária, na viabilidade celular e expressão de transportadores de membrana (ENaC) em linhagem celular renal M-1. Para os ensaios de viabilidade das células da linhagem M-1 foi empregado os testes colorimétricos Cristal Violeta e MTT, utilizando as concentrações de tratamento com fluoreto de sódio (NaF) a 10, 40, 100, 200 e 400 M, durante períodos experimentais de 24, 48, 72 e 96 h. As mesmas concentrações e os mesmos tempos foram utilizados no tratamento com cloreto de sódio (NaCl), utilizado como controle na possível interferência de Na+ na modulação das células. Para a investigação da influência do F: 1) nos canais ENaC foi utilizada a técnica de imunofluorescência e 2) para a análise de expressão gênica das subunidades que formam o ENaC, foi utilizada a técnica RT-PCR. Em nossos resultados pudemos observar que as maiores concentrações tanto de NaF quanto de NaCl provocaram a diminuição da viabilidade celular para ambos os ensaios de viabilidade, no entanto, foi possível observar algumas diferenças na resposta do tratamento com NaF em comparação com NaCl, por meio do ensaio Cristal Violeta. Não foi observado diferenças nas imagens de imunofluorescêcia, mas outros aspectos morfológicos foram vistos nessas imagens, como o aparecimento de domes celular, sugerindo que até mesmo a maior concentração de F não foi capaz de inibir a proliferação celular. Nosso resultado mais significativo foi em relação à expressão das subunidades dos canais de ENaC, onde a concentração de 400 M foi capaz de diminuir bruscamente a expressão das três subunidades do ENaC, enquanto as concentrações de 100 e 200 M mostraram apresentar expressão igual e em alguns casos até maior que o grupo controle. Pudemos concluir que doses de F na ordem de micromolares podem modular a expressão das subunidades formadoras do ENaC, positivamente quando em baixas concentrações e negativamente quando em concentrações elevadas. / The balance of fluoride (F) within the body is modulated by its ingestion, absorption and removal, and the kidneys, responsible for their excretion of the organism, are particularly vulnerable to the toxicity of F. The nephrotoxic effects of F involve marked structural changes in the kidneys , in addition, proteomic studies have shown large changes in the profile of proteins involved in key points in signal transduction. These effects may negatively influence ion transport in the kidneys. In view of this fact, the ionic transport in the epithelial sodium channel (ENaC) is limiting to the rate of sodium reabsorption in the kidneys, being essential for the maintenance of the electrolyte balance and homeostasis of the body. Thus, the objective of this work was to investigate the effects of F, using concentrations similar to those found in the nephron during dental fluorosis, cell viability and expression of membrane transporters (ENaC) in renal cell line M-1. For the M-1 cell line viability assays, the Crystal Violet and MTT colorimetric assays were used, using the 10, 40, 100, 200 and 400 M sodium fluoride (NaF) treatment concentrations during experimental periods of 24, 48, 72 and 96 h. The same concentrations and the same times were used in the treatment with sodium chloride (NaCl), used as control in the possible interference of Na + in the modulation of the cells. For the investigation of the influence of F: 1) in the ENaC channels, the immunofluorescence technique was used and 2) for the analysis of gene expression of the subunits that form the ENaC, the RT-PCR technique was used. In our results it was observed that the higher concentrations of NaF and NaCl caused a decrease in cell viability for both viability assays, however, it was possible to observe some differences in NaF treatment response in comparison to NaCl, through test Crystal Violet. No differences were observed in immunofluorescence images, but other morphological aspects were seen in these images, such as the appearance of cellular \"domes\", suggesting that even the highest F concentration was not able to inhibit cell proliferation. Our most significant result was the expression of the subunits of the ENaC channels, where the concentration of 400 M was able to decrease expression of the three subunits of the ENaC, whereas the concentrations of 100 and 200 M showed equal expression and in some cases even higher than the control group. We can conclude that doses in the order of micromolar the F can modulate the expression of the ENaC forming subunits, positively when in low concentrations and negatively when in high concentrations.

No description available.

No description available.

Aliskiren (ALS) is a direct renin inhibitor with low bioavailability and high drug cost. The goal of this study was to increase the bioavailability of ALS through nanoformulation. The optimized formulation was then evaluated in spontaneously hypertensive rats (SHRs). We developed an ALS poly(lactic-co-glycolic) acid nanoparticle (ALS-NP) through the emulsion–diffusion–evaporation method with various solvents, stabilizer concentrations, and centrifugation speeds. SHRs were orally dosed with 30 mg/kg ALS or dose equivalent ALS-NP. Several parameters were assayed in plasma and/or urine at baseline and 24 h post-dose, while pharmacokinetic analysis included serial sampling. The optimum formulation was found with ethyl acetate, a 1.00% w/v didodecyldimethylammonium bromide concentration, and a 10,000 r/min (15,554 g) centrifugation speed. A 168% relative bioavailability was observed as a result of ALS-NP administration along with significant, as determined by Student’s t-test, increases in the maximum ALS plasma concentration (p = 0.0189) and the area under the plasma concentration–time curve from 0 to infinity (p = 0.0095). Conversely, a reduction was found in oral volume of distribution (p = 0.0009) and oral clearance (p = 0.0298). Blood urea nitrogen increased significantly after dosing in both groups (p < 0.0001 and p < 0.0001); however, no statistical difference was found between endpoint levels (p > 0.05) following one-way analysis of variance (ANOVA). Kidney injury molecule-1 increased following ALS dosing (p = 0.0486), while ALS-NP showed a decrease (p = 0.027) which was also significantly decreased compared to ALS-Final (p = 0.0008) when examined using two-way ANOVA. Urinary potassium excretion decreased significantly, as shown by two-way ANOVA, only in the ALS group (p = 0.0274) which was also significantly reduced compared to ALS-NP-Final (p = 0.016). Using the current formulation and at the dosage tested, ALS-NP showed a more favorable pharmacokinetic profile and positive kidney changes compared to ALS in regard to select outcomes. Thus, NP formulation may further improve ALS renoprotection in addition to increasing bioavailabilty.

The most important and most common channels on cell membrane are voltage-gated Na+ and K+ channels. In so-called "excitable cells" like neurons and muscle cells, these channels open or close in response to changes in potential across the membrane in order to accomplish muscle contraction and transmit signals. By controlling the membrane potential, we observe extraordinary inactivation behaviors of the voltage-gated Na+ channels and the voltage-gated delayed rectifier K+ channels, which shows that electric stimulation pulses can temporarily close the Na+ and K+ channels, just as drugs, like tetrodotoxin (TTX) and tetraethylammonium (ETA), do. The Na/K pump is essential for living system and is expressed in virtually all cell membranes. The ionic transport conducted by Na/K pumps creates both an electrical and a chemical gradient across the plasma membrane, which are required for maintaining membrane potentials, cell volume, and secondary active transport of other solutes, etc. We use a pulsed, symmetric, oscillating membrane potential with a frequency close to the mean physiological turnover rate across the cell membrane to synchronize Na/K pump molecules. The pump molecules can work as a group, pumping at a synchronized pace after a long train of pulses. As a result, the pump functions can be significantly increased. After the pump molecules are synchronized, the applied electric-field frequency can gradually increase in order to resynchronize the molecules to a new, higher frequency. Modulating the pump molecules to a higher frequency leads to a significant increase of pump current. Synchronization and modulation of pump molecules can become a new method to study the function of Na/K pump molecules. This method has huge potential applications in clinic medical treatment. After single-fiber-level study, the final project is on organ level, the rat kidney, by using synchronization and modulation of Na/K pump molecules on the proximal tubule membrane. Because Na+ re-absorption is directly related to the function of the Na/K pump, the more active Na/K pumps are, the more Na+ ions can be absorbed, which results in an increased potential inside the renal proximal tubule. This project is the first step of synchronization and modulation applied on the level of an organ.

archives@tulane.edu / Background Ankle brachial index (ABI) is a noninvasive measure of subclinical cardiovascular disease (CVD) and atherosclerosis of the lower extremities. Low and high levels of ABI are associated with cardiovascular mortality and vascular calcification in dialysis chronic kidney disease (CKD) patients. However, the association of the spectrum of vascular calcification with low and high ABI is not well studied in pre-dialysis CKD patients. The purpose of this study is to investigate the association of both low and high ABI with the risk of vascular calcification in CKD patients. Methods We recruited 243 patients with pre-dialysis CKD from the great New Orleans area between 2010 and 2012. Our study used a cross-sectional design with ABI and CAC measured at the same visit. Continuous ABI measurements were taken and further classified into four categories : <=0.9 (low ABI) >0.9-<1.0 (borderline), 1.0-<1.4 (normal), >=1.4 (high). Level of vascular calcification were considered as the outcome and calculated by agatston score. Three categories of CAC is defined as: CAC agaston score=0, 0-100, >100. Three cumulative logit models were applied to the data. The first is an unadjusted univariate model, the second adjusts for baseline demographics, and the third adjusts for baseline demographics and covariates that are associated with CAC. Logistic regression methods were used to calculate the odds ratio of having a higher CAC score for CKD patients. Results We found a significant association between ABI and vascular calcification. All three models returned consistently significant result (p=0.0005, 0.0005, 0.0037, respectively) for the association between ABI and CAC. In addition, low ABI (ABI≤0.9) is also associated with an increased risk of CAC and severe CAC (OR=6.183, 95%CI(1.085, 35.228)). High ABI (>1.4) is also associated with an increase in CAC and severe CAC (OR=5.064, 95%CI (1.696, 15.122)). Borderline ABI (0.9<ABI<1.0) is not associated with an increase in CAC or severe CAC (OR=2.704, 95% CI (0.702, 10.418). Conclusion Compared to normal ABI level, low and high ABIs are both significantly associated with an increased risk of coronary artery calcification and severe coronary artery calcification in CKD patients. / 1 / Shuo Bai

Age-related increases in arterial stiffness are mediated in part by mitochondrial dysfunction. Sirtuin 3 (SIRT3) is a mitochondrial NAD+-dependent deacetylase that regulates mitochondrial function. SIRT3 deficiency contributes to physiological dysfunction in a variety of pathological conditions. Here, we tested the hypothesis that age-associated arterial stiffness, assessed by aortic pulse wave velocity (PWV), would be accompanied with decreased renal and aortic SIRT3 expression and activity due to decreased NAD+ levels. We further tested whether boosting NAD+ concentration with nicotinamide riboside (NR), a NAD+ precursor, for 6 months would reverse the effects of aging. Old (~26 mo, n = 9) C57BL/6 male mice had higher PWV vs. young (6 mo, n = 10) (448 ± 14 vs 382 ± 13, p < 0.005), which was associated with reduced arterial SIRT3 protein (0.365 ± 0.088 AU’s vs 1.000 ± 0.000); p < 0.05). Furthermore, SIRT3 deficient male mice demonstrated higher PWV compared to age-matched control mice (480 ± 21 n = 6 vs. 391 ±12 n = 7, p < 0.005). Aortic SIRT3 protein was negatively correlated with PWV (r=-0.7798, p < 0.005). Old mice also exhibited reduced kidney SIRT3 protein (0.73 ± 0.10 AU’s) compared to young controls (1.00 ± 0.00; p = 0.0192) and reduced NAD+ (918.6 ± 50.5 pmol/mg vs. young 1302.0 ± 56.6 pmol/mg, p = 0.0036). Old mice supplemented with NR had increased NAD+ concentration in kidney tissue (1303.0 ± 90.2 pmol/mg) however, had no effect on normalizing age-associated arterial stiffness (402 ± 18 old with NR vs 418 ± 15 old; p = 0.78). Here we show for that SIRT3 protein correlates with aortic stiffness and may be required for the maintenance of healthy arteries and for the first time that supplementation with NR, a commercially available supplement, ameliorates age-associated decreases in renal NAD+ demonstrating therapeutic potential in kidney disease.