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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.
21

Shortage of antidiabetic and antihypertensive in the context of the initial stage of the COVID-19 pandemic in Peru / Desabastecimiento de antidiabéticos y antihipertensivos en el contexto de la etapa inicial de la pandemia por la COVID-19 en Perú

Herrera-Añazco, Percy, Valenzuela-Rodríguez, Germán, Torres-Pesantes, Luciana, Toro-Huamanchumo, Carlos J. 21 October 2021 (has links)
Background: An adequate supply of medicines in health establishments will increase the possibility of adequate control of hypertension and diabetes. Objective: To determine the shortage of antidiabetic and antihypertensive drugs at the national level in the context of the initial stage of the COVID-19 pandemic in Peru. Material y methods: Analysis of the "Sistema Integrado de Suministro de Medicamentos e Insumos Médicos Quirúrgicos" (SISMED) Database, between June 13th and July 15th, 2020, according to the "National list for medicines of essential medicines" (PNUME) of Ministry of health. Results: And between 4 and 96% of the departments have a total shortage of at least one antidiabetic, and 4% and 96% of at least one antihypertensive. The most depleted antidiabetic was Metformin 500 mg, and the most depleted antihypertensive drugs were Labetalol 5 mg / ml iny, Atenolol 50 mg tab and Carvedilol 6.25 mg tab. The percentage of distribution was higher in hospitals and specialized institutes in comparison with primary health facilities. Conclusions: There is a shortage of antihypertensive and antidiabetic drugs in health centers in Peru. © 2021 Medical Body of the Almanzor Aguinaga Asenjo National Hospital. / Revisión por pares
22

Effect of glucose control on satiation, gut hormones and metabolic response to a meal in type 2 diabetes mellitus

Mourad, Carine J. January 2008 (has links)
No description available.
23

Effective utilization of oral hypoglycemic agents to achieve individualized HbA1c targets in patients with type 2 diabetes mellitus

Bannister, Margaret, Berlanga, J. 08 August 2016 (has links)
Yes / Type 2 diabetes is a progressive condition that may require the combination of three oral treatments to achieve optimal glycemic management to prevent microvascular and macrovascular complications whilst minimizing the risk of acute complications and side effects or adverse reactions to treatments. With the widening availability of treatment options and increasing importance of individualized treatment pathways, including personalized HbA1c targets, this article will explore the mode of action of currently available oral treatments, factors to consider when individualizing HbA1c targets, the relevance of estimated glomerular filtration rate assessment, and the importance of reviewing the clinical impact of all treatment decisions.
24

Mechanistic studies of sodium-glucose cotransporter-2/dipeptidyl peptidase-iv blockade and niacin on pancreatic islet function and glucose homeostasis.

January 2013 (has links)
胰腺內的胰島具有極其重要的功能,通過產生并分泌一系列的胰島荷爾蒙,特別是能控制機體葡萄糖利用的胰島素,來調節體內血糖穩態。胰島素的分泌受到多種因素或信號通路的調節。据信,在臨床上表現出來明顯的高血糖症的時候,胰島細胞的分泌功能已經出現典型性的缺陷。由此,大量的研究證據指出,2 型糖尿病表現出來的代謝型缺陷主要為胰島功能紊亂,而并不是周圍組織胰島素抵抗。這表明,胰島素功能缺陷是早於高血糖症的發生的。另一方面,大量證據表明長期性的高血糖會導致胰島 細胞功能紊亂。鑒於此,揭示胰島功能調節的潛在機理并闡明胰島功能与高血糖症之間的關係變得尤為重要。 / 在臨床上表現出能調節胰島功能和血糖控制的相關因子正與日俱增。其中極具研究價值的是一種多肽,稱作胰高血糖素様肽(GLP-1),其作用表現在通過增強胰島素分泌和胰島素敏感性來增強胰島 細胞的功能和增值。GLP-1 在體內的降解能被DPP-4 的抑製劑所延阻。同時,通過對一種名為SGLT2 的葡萄糖轉運蛋白的抑制,機體內的血糖水平能被顯著降低。這一作用是通過阻止腎臟對葡萄糖的重吸收來實現的,並且是不依賴于胰島素的。由於DPP-4 抑制所表現的最終生理作用需要通過胰島素的信號通路來實現,但SGLT2 的抑制卻不依賴於胰島素,由此不難想象,對SGLT2 和DPP-4 的聯合抑制在2 型糖尿病的血糖控制方面具有潛在的協同效應。即通過對SGLT2 的抑制來顯著降低血糖水平,從而促進GLP-1 在體內的作用效應。因此,本研究的第一部分研究SGLT2 和DPP-4 的單一或聯合抑制(利用SGLT2 抑製劑BI-38335 和DPP-4 抑製劑linagliptin)在二型糖尿病動物模型db/db老鼠種對胰島功能和體內葡萄糖穩態的作用。在此研究中,我們比較了SGLT2 和DPP-4 單一抑制或聯合抑制對db/db 老鼠胰島功能的影嚮。研究發現,所有的實驗組都能顯著降低血糖以及糖化血紅蛋白(HbA1c)的水平,而且聯合抑制組表現出更叫顯著的效應。聯合抑制組增強了胰島細胞的胰島素分泌功能,改善葡萄糖耐受并增加胰島素的敏感性。於此一致的是,聯合抑制組降低了β細胞凋亡和胰島免疫細胞標記物,並且抑制了与TLR2 信號通路相關的一系列炎症分子,通過則一系列作用實現對胰島的保護。上述研究表明,對SGLT2 和DPP-4 的聯合抑制在對胰島功能和胰島形態學上的保護至少能夠表現出加性效應,從而更好實現對血糖的調控。 / 在第一部分的工作中,我們利用的動物模型db/db 老鼠是一類較嚴重的糖尿病動物模型,它表現出及其嚴重的高血糖症,糖耐受失調同β細胞缺陷。我們集中于研究SGLT2 和DPP-4 的抑制對這類嚴重糖尿病的胰島功能的調節,具體表現在對胰島β細胞功能的正向調節,包括胰島素分泌功能的增強和β細胞質量的增加。廣為接受的一點是,胰島素抵抗和胰島素分泌功能的缺失最能表徵從正常葡萄糖耐受發展到2 型糖尿病的這一進程。這一進程的早期主要表現為由肥胖或衰老而引起的代償性的胰島素抵抗,此時伴有正常或受損的葡萄糖耐受以及正常的胰島素分泌功能。此時,任何能影響胰島功能的因素都會減緩或加速2 型糖尿病的發生。鑒於此,研究此类因素從而到达阻止2 型糖尿病的发生就显得尤为重要。因此,在本研究的第二部分,我们研究利用高脂飼料诱导的肥胖老鼠模型和老化的老鼠模型来分别研究煙酸(niacin 或 nicotinic acid)对胰岛功能的影響。煙酸是一種臨床上廣汎使用的降血脂藥物,但近年來的研究發現長期或高劑量的使用會導致高血糖症和血糖控制失調的出現,然而這一現象產生的具體機製並不清楚。因此,我們第二部分的研究集中於揭示煙酸引起的高血糖症是否歸因於其對胰島功能的破壞,以及潛在的分子機制。我們的研究發現,在肥胖老鼠和老齡鼠中,煙酸能夠引起高血糖症,破壞葡萄糖體內穩態並且降低胰島素分泌能力;另一方面,煙酸增加饑餓血清胰島素水平並且引起葡萄糖耐受實驗中第一期胰島素分泌缺陷。體內和體外實驗還發現煙酸誘導煙酸受體GPR109a,UCP2 和PPARγ的表達增加以及SIRT1 的表達和NAD,NAD/NADH 降低。通過基因沉默技術降低GPR109a 在β細胞中的表達,我們發現煙酸的上述作用都被極大的減弱,從而揭示了煙酸引起的胰島功能降低是由其受體GPR109a 介導的。 / 總闊來說,我們的研究揭示了DPP-4 同SGLT2 的聯合抑制在增強胰島功能和胰島形態學上的保護以及改善胰島素抵抗等方面能夠表現出加性效應,從而更好實現對血糖的調控。另一方面,我們的研究闡述了煙酸通過它的受體GPR109a 以及其下游信號通路如PPARγ和SIRT1 來損害胰島細胞功能。綜上所述,我們當前的研究證實了一系列因素對胰島功能的調控,從而充實并擴展了我們對胰島功能和血糖控制以及2 型糖尿病之間關係的認識。 / Pancreatic islets are of great importance to govern glucose homeostasis through production and secretion of islet peptide hormones, notably insulin, which functions as a master regulator to control glucose disposal in the body. Insulin secretion is regulated by various factors and signaling pathways. It is well known that islet insulin secretory function is typically lost by the time when signs of hyperglycemia that becomes clinically apparent. Thus, it has been pointed out that islet dysfunction, rather than peripheral insulin resistance, is the primary defect of type 2 diabetes mellitus (T2DM), indicating that deficiencies in islet function are prior to the onset of hyperglycemia. On the other hand, it is also widely accepted that chronic hyperglycemia results in islet β cells dysfunction. In this regard, it is of great importance to unravel the underlying mechanisms by which islet function is regulated, thus elucidating the relationship between hyperglycemia and islet function. / There are ever increasing candidates of clinically relevant factors identified as criticalregulators for islet function and glycemic control. Of great interest is the glucagon-like peptide 1 (GLP-1) that improves β cell function and proliferation and its degradation can be delayed by dipeptidyl peptidase-4 (DPP-4) inhibition. Meanwhile, plasma glucose levels can be remarkably lowered by inhibition of sodium-glucose co-transporter 2 (SGLT2), through blockade of renal glucose reabsorption. In this regard, since the mode of action of SGLT2 inhibition is independent of insulin but the efficacy of DPP-4 inhibition relies on the insulin signalling, it is plausible to hypothesize that sustained lowering of plasma glucose by SGLT2 inhibition can facilitate the actions of GLP-1 from DPP-4 inhibition, thus leading to a potential synergistic effect on islet function and glycemic control. Accordingly, the first part of this study was to investigate the combination effects of SGLT2 and DPP-4 blockade on islet function and glucose homeostasis using an animal model of T2DM, the db/db mice. We compared the effects of either DPP-4 inhibition (by a DPP-4 inhibitor, linagliptin) or SGLT2 inhibition (by an SGLT2 inhibitor, BI-38335) individually and in combination on islet function and glycemic control in db/db mice. Active treatments markedly enhanced islet function, improved glycemic control and reduced islet and peripheral tissue inflammation, with the combined treatment showing the greater effects. These data indicate that combined SGLT2 inhibition with DPP-4 inhibition work additively to exhibit benefits to islet function, inflammation and insulin resistance, thus improving glycemic control. / In the first part, we investigated a positive regulation of islet function in overt diabetic mice, in which there are severe hyperglycemia and β cell failure. It is widely accepted that the progression from normal glucose tolerance to T2DM is characterized by dual defects that include insulin resistance and an insulin secretory defect caused by β cell dysfunction. In the early stage, there is compensated insulin resistance resulting from obesity or aging with normal or even impaired glucose tolerance as well as nearly normal insulin secretory capacity. As such, any factors that affect islet function in this stage may delay or accelerate the onset of diabetes. In this regard, it is noteworthy to study the regulation of such factors in islet function in order to prevent the development of T2DM. Thus, in the second part, we investigated how islet function was regulated by a widely used lipid-lowering drug, niacin (nicotinic acid), in obese mice and aged mice. Niacin has been known to impair euglycemic control during prolonged and high dose treatments but the underlying mechanism(s) whereby the islets are involved remains unclear. As such, we aimed at elucidating whether this hyperglycemic effect is due to the dysfunction of pancreatic islet and, if so, the underlying mechanism(s) involved. We investigated the direct effects of niacin on islet function and insulin resistance in HFD-induced obese (DIO) mice and aged mice. Our results showed that eight-week treatments with niacin impaired glycemic control and islet function in DIO and aged mice. Moreover, niacin treatments significantly induced PPARγ and GPR109a expression but decreased SIRT1 expression in pancreatic islets, while islet morphology remained unchanged. In vitro studies showed that niacin decreased glucose-stimulated insulin secretion (GSIS), cAMP, NAD/NADH ratio, and mitochondrial membrane potential (ΔΨm) but increased reactive oxygen species (ROS) transiently, while upregulated expression levels of UCP2, PPARγ and GPR109a in INS-1E cells. In corroboration, the decrease in GSIS and cAMP levels were abolished by the knockdown of GPR109a. These data indicate that chronic treatment of niacin induces hyperglycemia, which is due, partly, to impaired pancreatic islet function, probably via the mediation of islet niacin receptor GPR109a. / Collectively, our study has revealed that inhibition of DPP-4 or SGLT2 alone can improve islet function, and combined inhibition of DPP-4 and SGLT2 works additively to exhibit benefits to islet cell function/morphology, inflammation and insulin resistance, thus improving glycemic control. On the other hand, we have also elucidated that niacin impairs islet β cell function through GPR109a and downstream signaling pathways such as PPARγ and SIRT1. Taken together, the present study has shown the regulation of is let β cell function by different factors, which has an added advance to our knowledge about the intricate relationship between islet function and hyperglycemia and T2DM. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chen, Lihua. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 168-195). / Abstracts also in Chinese. / Abstract --- p.i / 摘要 --- p.iv / Acknowledgement --- p.vii / List of Publications --- p.viii / List of Abbreviations / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1 --- Endocrine pancreas --- p.2 / Chapter 1.1.1 --- Structure and composition of endocrine pancreas --- p.3 / Chapter 1.1.2 --- Architecture and composition of the islet --- p.3 / Chapter 1.1.3 --- Endocrine cells and their function --- p.5 / Chapter 1.2 --- Disorders of the endocrine pancreas --- p.9 / Chapter 1.3 --- Insulin --- p.10 / Chapter 1.3.1 --- Insulin Structure --- p.10 / Chapter 1.3.2 --- Insulin actions and insulin receptor --- p.11 / Chapter 1.3.3 --- Insulin secretion --- p.12 / Chapter 1.3.3.1 --- Glucose-induced insulin secretion --- p.13 / Chapter 1.3.3.2 --- Phasic insulin secretion --- p.14 / Chapter 1.3.4 --- The regulation of insulin secretion --- p.16 / Chapter 1.3.5 --- Autocrine insulin feedback --- p.20 / Chapter 1.4 --- Diabetes mellitus --- p.21 / Chapter 1.4.1 --- Type 1 diabetes mellitus (T1DM) --- p.22 / Chapter 1.4.2 --- Type 2 diabetes mellitus (T2DM) --- p.23 / Chapter 1.4.3 --- Obesity and T2DM --- p.23 / Chapter 1.4.4 --- Islet dysfunction and T2DM --- p.25 / Chapter 1.5 --- Incretin hormones and DPP-4 inhibition --- p.27 / Chapter 1.5.1 --- Incretin hormones --- p.27 / Chapter 1.5.2 --- Functions of incretin hormones --- p.30 / Chapter 1.5.3 --- Regulation of GLP-1 --- p.34 / Chapter 1.5.4 --- Incretin-based therapy for T2DM --- p.35 / Chapter 1.6 --- Sodium-dependent glucose cotransporter 2 (SGLT2) and its inhibitors --- p.38 / Chapter 1.6.1 --- Sodium-dependent glucose cotransporter 2 (SGLT2) --- p.38 / Chapter 1.6.2 --- Rationale for SGLT2 inhibition --- p.40 / Chapter 1.6.3 --- Consequences of SGLT2 inhibition --- p.41 / Chapter 1.6.4 --- Strategies of SGLT2 inhibition --- p.43 / Chapter 1.6.4.1 --- SGLT2 inhibitors --- p.44 / Chapter 1.6.4.1 --- SGLT2 inhibitors --- p.47 / Chapter 1.7 --- Niacin (nicotinic acid) and its clinical usage --- p.49 / Chapter 1.7.1 --- Niacin general introduction --- p.49 / Chapter 1.7.2 --- General roles of niacin --- p.49 / Chapter 1.7.3 --- Anti-lipolytic effect --- p.50 / Chapter 1.7.4 --- Niacin receptor --- p.51 / Chapter 1.7.5 --- Hyperglycemic effect of niacin --- p.52 / Chapter 1.8 --- General hypothesis --- p.54 / Chapter Chapter 2 --- General Materials and Methods --- p.56 / Chapter 2.1 --- Experimental animal models --- p.57 / Chapter 2.1.1 --- Animal model of type 2 diabetes --- p.57 / Chapter 2.1.2 --- High-fat diet-induced obese mice --- p.58 / Chapter 2.1.3 --- Aged mice --- p.59 / Chapter 2.2 --- INS-1E cell culture and treatment --- p.59 / Chapter 2.2.1 --- Mouse pancreatic islet isolation --- p.59 / Chapter 2.2.2 --- Primary culture of isolated pancreatic islets --- p.60 / Chapter 2.3 --- Pancreatic islet isolation and culture --- p.60 / Chapter 2.4 --- Glucose-stimulated insulin secretion (GSIS) assay --- p.61 / Chapter 2.5 --- Assessment of glucose homeostasis --- p.61 / Chapter 2.6 --- Determination of mRNA expression --- p.62 / Chapter 2.6.1 --- Design of specific primers --- p.63 / Chapter 2.6.2 --- Total RNA extraction and cDNA synthesis --- p.63 / Chapter 2.6.3 --- Real-time PCR analysis --- p.64 / Chapter 2.7 --- Detection of protein expression --- p.64 / Chapter 2.7.1 --- Western blotting analysis --- p.64 / Chapter 2.7.2 --- Immunofluorescent staining --- p.65 / Chapter 2.8 --- Biochemical analyses --- p.65 / Chapter 2.8.1 --- Plasma insulin and blood HbA1c levels --- p.65 / Chapter 2.8.2 --- Detection of cAMP --- p.66 / Chapter 2.8.3 --- NAD and NADH determination --- p.66 / Chapter 2.9 --- Detection of intracellular ROS --- p.67 / Chapter 2.10 --- Detection of mitochondrial membrane potential --- p.67 / Chapter 2.11 --- Statistical analysis --- p.67 / Chapter Chapter 3 --- Effects of Combining Linagliptin Treatment with BI-38335, A Novel SGLT2 Inhibitor, on Pancreatic Islet Function and Inflammation in db/db Mice --- p.70 / Chapter 3.1 --- Abstract --- p.71 / Chapter 3.2 --- Introduction --- p.72 / Chapter 3.3 --- Materials and Methods --- p.74 / Chapter 3.3.1 --- Animal model and experimental design --- p.74 / Chapter 3.3.2 --- In vivo glucose homeostasis --- p.75 / Chapter 3.3.3 --- Pancreas and islet studies --- p.76 / Chapter 3.3.4 --- Biochemical analyses --- p.77 / Chapter 3.3.5 --- Real-time PCR analyses --- p.77 / Chapter 3.3.6 --- Statistical analysis. --- p.78 / Chapter 3.4 --- Results --- p.78 / Chapter 3.4.1 --- Treatments with DPP-4 and SGLT2 inhibitors lower plasma glucose --- p.78 / Chapter 3.4.2 --- Treatments with DPP-4 and SGLT2 inhibitors improve glycemic --- p.80 / Chapter 3.4.3 --- Pancreatic islet function in db/db mice --- p.83 / Chapter 3.4.4 --- Pancreatic islet and peripheral tissue inflammation --- p.86 / Chapter 3.4.5 --- Islet morphology and preserved beta cells --- p.89 / Chapter 3.5 --- Discussion --- p.93 / Chapter Chapter 4 --- Niacin-Induced Hyperglycemia Is Mediated via Niacin Receptor GPR109a in Pancreatic Islets --- p.98 / Chapter 4.1 --- Abstract --- p.99 / Chapter 4.2 --- Introduction --- p.100 / Chapter 4.3 --- Research design and methods --- p.102 / Chapter 4.3.1 --- Animal model and experimental design --- p.102 / Chapter 4.3.2 --- In vivo glucose homeostasis --- p.102 / Chapter 4.3.3 --- Pancreas and islet studies --- p.103 / Chapter 4.3.4 --- INS-1E cell culture and treatment --- p.103 / Chapter 4.3.5 --- Construction of small interfering RNA for GPR109a --- p.103 / Chapter 4.3.6 --- Real-time PCR analyses --- p.104 / Chapter 4.3.7 --- Western blotting assay --- p.104 / Chapter 4.3.8 --- Detection of intracellular and mitochondrial ROS --- p.105 / Chapter 4.3.9 --- Detection of mitochondrial membrane potential (ΔΨm) --- p.105 / Chapter 4.3.10 --- Measurement of cAMP levels --- p.105 / Chapter 4.3.11 --- Determination of NAD and NADH levels --- p.106 / Chapter 4.3.12 --- Measurement of cell viability --- p.106 / Chapter 4.3.13 --- Statistical analysis --- p.106 / Chapter 4.4 --- Results --- p.106 / Chapter 4.4.1 --- Glycemic control in HFD-induced obese mice --- p.106 / Chapter 4.4.2 --- Pancreatic islet function in HFD-induced obese mice --- p.110 / Chapter 4.4.3 --- Pancreatic islet morphology and gene expression --- p.112 / Chapter 4.4.4 --- INS-1E function and intracellular levels of cAMP, NAD, and NADH --- p.114 / Chapter 4.4.5 --- Gene expression in INS-1E cells --- p.117 / Chapter 4.4.6 --- Status of ROS and ΔΨm in INS-1E cells --- p.119 / Chapter 4.4.7 --- GPR109a knockdown in INS-1E cells --- p.122 / Chapter 4.5 --- Discussion --- p.129 / Chapter Chapter 5 --- Niacin Impairs Pancreatic Islet Glucose-Stimulated Insulin Secretion in Aged Mice through The Suppression of SIRT1 Signaling --- p.134 / Chapter 5.1 --- Abstract --- p.135 / Chapter 5.2 --- Introduction --- p.136 / Chapter 5.3 --- Research design and methods --- p.139 / Chapter 5.3.1 --- Animal model and experimental design --- p.139 / Chapter 5.3.2 --- In vivo glucose homeostasis --- p.139 / Chapter 5.3.3 --- Pancreas and islet studies --- p.140 / Chapter 5.3.4 --- Real-time PCR analyses --- p.140 / Chapter 5.3.5 --- Western blotting assay --- p.140 / Chapter 5.3.6 --- NAD and NADH determination --- p.141 / Chapter 5.3.7 --- NEFA determination --- p.141 / Chapter 5.3.8 --- Statistical analysis --- p.141 / Chapter 5.4 --- Results --- p.142 / Chapter 5.4.1 --- Glycemic control in middle aged mice --- p.142 / Chapter 5.4.2 --- Pancreatic islet function in HFD-induced obese mice --- p.147 / Chapter 5.4.3 --- NAD, NADH levels in pancreatic islet --- p.149 / Chapter 5.4.4 --- Genes expression in pancreatic islet --- p.151 / Chapter 5.5 --- Discussion --- p.150 / Chapter Chapter 6 --- General discussion --- p.156 / Chapter 6.1 --- Combined inhibition of DPP-4 with SGLT2 on islet function, inflammation and insulin resistance in T2DM --- p.158 / Chapter 6.2 --- Niacin impairs islet function in high-fat diet-induced obese mice and aged mice --- p.161 / Chapter 6.3 --- General conclusion --- p.164 / Chapter 6.4 --- Future directions --- p.166 / Chapter Chapter 7 --- Bibliography --- p.167
25

Epidemiological burden of depression and its impact on adherence to oral hypoglycemic agents and related economic outcomes in patients with type 2 diabetes

Kalsekar, Iftekhar D. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2004. / Title from document title page. Document formatted into pages; contains xiv, 287 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 261-282).
26

Investigation on the anti-diabetic effects of selected natural products/Chinese herbs by inhibiting the activity of sodium-glucose cotransporter 2 (SGLT2).

January 2012 (has links)
糖尿病是一種以不正常的高血糖為主要特徵的長期性的糖代謝紊亂疾病。二型糖尿病是常見的糖尿病類型,多於九成的糖尿病病人患有此種類型。各種引起糖尿病的病因最終都會導致血糖過高,並且最終會引起有關眼睛,腎臟,神經和血管系統的併發癥。迄今,糖尿病正影響著大約世界6%的人口,而現在患病率依然在逐年增加。在香港,由於高能量的食和缺乏運動,越來越多的老年人和青年人正在遭受著糖尿病的困擾。糖尿病不是一種致命性的疾病,但是如果沒有採取好的治療控制措施,糖尿病最終會引起一些併發癥,這些併發癥最終會使糖尿病患者走向死亡。高血糖癥不僅是糖尿病的主要特徵,而且也是引起各種糖尿病併發癥的重要因素,在二型糖尿病的治療當中,根據各種病理因素,市場上已經研製出了很多西藥來治療糖尿病。然而,它們都有一些副作用的限制。因此,我們需要通過綜合治療和通過新的途徑研製新的製劑來控制血糖水平,保護病人遠離長期併發癥的困擾。如今,腎臟在血糖平衡中的重要角色已經被很好的認知。 在過去的二十年裡, 通過減少血糖在腎臟的重吸收來增加尿液中血糖的排出,從而達到降低體內血糖水平的方法已經被提出并認為是治療糖尿病的一直新的途徑。 在腎臟中,鈉葡萄糖共轉運體2(SGLT 2)主要負責葡萄糖的重吸收,因此,鈉葡萄糖共轉運體2(SGLT 2)抑製劑被認為是一種有潛質的新型的治療糖尿病的製劑。然而,市場上至今沒有成功研製這種製劑。达格列嗪(dapagliflozin),作為一種最有潛質的鈉葡萄糖共轉運體2(SGLT 2)抑製劑,依然處於臨床三期實驗。至今,對具有鈉葡萄糖共轉運體2(SGLT 2)抑製作用的天然產物和傳統中醫藥的信息報導非常少。中醫中藥的治療理念強調整體治療,從此點看來,爲了使糖尿病患者遠離長期的糖尿病併發癥的困擾,中醫中藥可能比西藥更有優勢。 / 因此,本研究的目的是尋找那些具有體外能專門抑制鈉葡萄糖共轉運體2(SGLT 2)並且體內能通過增加尿糖排出來降低血糖水平的抗糖尿天然產物或傳統中藥。從文獻分析中找到了經常用於治療糖尿病的11種中藥和兩種天然產物。 / 試管實驗確立了五味子醇提物和丹皮酚對表達了人的鈉葡萄糖共轉運體2(SGLT 2)基因的COS 7細胞鏈中鈉葡萄糖共轉運體2對¹⁴C-α-甲基- D-葡萄糖苷的吸收作用具有很強的抑制作用。 / 生物活性引導的片段分析確立了五味子醇提物中的活性片段--乙酸乙酯:甲醇(4:6)(F8)片段具有明顯的專門抑制鈉葡萄糖共轉運體2的作用。本實驗也對F8進行了高效液相色譜和液質聯用色譜分析。五味子中三種常見的化合物:五味子甲素,五味子乙素和五味子醇甲存在于F8中,但濃度都很低。試管實驗顯示,這三種常見化合物均無抑制鈉葡萄糖共轉運體2的作用。因此得出結論,這三種常見的五味子化合物不是F8中有效的抑制鈉葡萄糖共轉運體2的活性成份。 / 本實驗也利用動物實驗調查了丹皮酚的抗糖尿作用。糖尿病大鼠被餵食了三個星期的丹皮酚,基礎血糖實驗和尿糖排出實驗均無陽性結果。 / Diabetes Mellitus (DM) is a chronic disorder of glucose metabolism characterized by abnormally high blood glucose level. Type 2 DM is the common form of diabetes which accounts for more than 90% of all DM cases. All causes of diabetes ultimately lead to hyperglycemia, and it can cause the late complications involving the eyes, kidneys, nerves and blood vessels, which are harmful to health. DM is now affecting about 6% population of the world, and the prevalence is still increasing quickly year by year. In Hong Kong, more and more elderly and youth are suffering from diabetes because of lacking of exercise and high energy diet. DM is not a fatal disease, but if no good action is taken, it can finally cause some kinds of complications, which can lead the patients to the end of their lives. Hyperglycemia is the major characteristics of diabetes, and it is also an important factor which induces all kinds of diabetic complications. In the therapy of type 2 diabetes, a lot of western medicine have been developed in the market according to various pathological causes. However, they have limitations such as existence of side effects. Therefore, combination therapy and development of new agents with novel mechanisms should be required to control the glycemic level and protect the patients from the long-term complications. Nowadays, the significance of the kidney's role in glucose homeostasis is well recognized. Glucose excretion with urine by reducing the renal glucose reabsorption to attenuate the glycemic level has been considered as a new mechanism to treat diabetes since the past two decades. Inhibitors on sodium glucose co-transporters 2 (SGLT 2) which are responsible for the glucose reabsorption in kidney are considered as a kind of new agents that have a potential on the treatment of diabetes. However, there is still no such kind of drug developed in the market, since the most potential one, dapagliflozin, is still on Phase III clinical trial. So far, only few information is found on natural products/traditional Chinese medicines (TCMs) that possess SGLT inhibitory action. Regarding the protection of patients from long-term complications, Chinese medicine which consider the body as a whole, may have advantages over western drugs. / Therefore, the aim of this study is to search for anti-diabetic TCM/natural products which specifically inhibit the activity of SGLT2 in vitro and attenuate plasma glucose level in vivo via increasing glucose excretion through urination. From literature review, 11 TCMs and 2 natural products frequently used in treating DM were selected for screening. / Using hSGLT 1 and hSGLT 2-expressed COS-7 cell lines as a model, in vitro study demonstrated that Fructus Schisandrae chinensis (ethanolic extract) and paeonol posses the most potent inhibitory effect on SGLT 2 in the in vitro ¹⁴C-α-methyl-D-glucopyranoside (¹⁴C-AMG) uptake assay. / The purification of active fraction(s) in ethanolic extract of Schisandrae chinensis fructus was carried out using the bioassay-guided fractionation assay. The ethyl acetate-methanol (4:6) fraction (F8) was selected with significant specific inhibitory effect on SGLT 2. UPLC and LC/MS-MS profiles of F8 were also given in this study. The concentrations of three common compounds of Fructus Shisansrae chinensis: deoxyschisandrin, schisandrin B (γ-schisandrin) and schisandrin were shown very low concentration in F8, the results of uptake assay showed none of these three compounds have inhibitory effects on SGLT 2. It is concluded that these three common compounds in Schisandrae chinensis fructus are not the effective ingredients in F8 which can specifically inhibit SGLT 2. / The anti-diabetic effects of paeonol in treating type 2 DM was investigated in animal study. Paeonol (200 and 300 mg/mL) was given to the type 2 diabetic rat model - Zucker Diabetic Fatty (ZDF) rats for three weeks, the results showed no positive effects on the basal glycaemia test and urinary glucose excretion test. / 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. / Qu, Yue. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 141-153). / Abstracts also in Chinese. / TABLE OF CONTENTS / ABSTRACT --- p.iv / 摘要 --- p.vii / ACKNOWLEDGEMENT --- p.ix / LIST OF ABBREVIATIONS --- p.x / LIST OF TABLES --- p.xiii / LIST OF FIGURES --- p.xiv / TABLE OF CONTENTS --- p.1 / Chapter CHAPTER 1 --- INTRODUCTION --- p.8 / Chapter 1.1 --- Definition, diagnosis, classification and epidemiology of Diabetes Mellitus --- p.8 / Chapter 1.1.1 --- Definition of Diabetes Mellitus --- p.8 / Chapter 1.1.2 --- Diagnosis of Diabetes Mellitus --- p.8 / Chapter 1.1.3 --- Classification of Diabetes Mellitus --- p.9 / Chapter 1.1.4 --- Prevalence of Diabetes Mellitus --- p.11 / Chapter 1.2 --- Glucose Homeostasis and Diabetes Mellitus --- p.12 / Chapter 1.2.1 --- General Description --- p.12 / Chapter 1.2.2 --- Kidney's role in Glucose Homeostasis --- p.14 / Chapter 1.2.2.1 --- Gluconeogenesis in the Kidney --- p.15 / Chapter 1.2.2.2 --- Glucose Reabsorption in the Kidney --- p.15 / Chapter 1.2.2.3 --- Renal glucose transporters --- p.17 / Chapter 1.2.2.4 --- Disorders with abnormal renal glucose transport --- p.19 / Chapter 1.3 --- Etiology of Diabetes Mellitus --- p.20 / Chapter 1.3.1 --- Pancreatic β cell dysfunction --- p.21 / Chapter 1.3.2 --- Insulin resistance --- p.21 / Chapter 1.4 --- Diabetic complications --- p.23 / Chapter 1.5 --- Treatment of type 2 Diabetes Mellitus --- p.25 / Chapter 1.5.1 --- Conventional therapy of type 2 Diabetes Mellitus --- p.25 / Chapter 1.5.2 --- New mechanism for the treatment of type 2 Diabetes Mellitus - Inhibition of glucose reabsorption by glucose transporters in Kidney --- p.29 / Chapter 1.6 --- Traditional Chinese Medicine for Diabetes Mellitus --- p.30 / Chapter 1.7 --- Project objective --- p.33 / Chapter CHAPTER 2 --- TRADITIONAL CHINESE HERBAL MATERIALS AND NATURAL PRODUCTS --- p.36 / Chapter 2.1 --- Materials --- p.36 / Chapter 2.2 --- General description and anti-diabetic effects of selected herbs/natural products --- p.38 / Chapter 2.3 --- Extraction Method --- p.45 / Chapter CHAPTER 3 --- IN VITRO STUDIES OF THE INHIBITORY EFFECT OF SELECTED TRADITIONAL CHINESE HERBS AND NATURAL PRODUCTS ON SODIUM GLUCOSE COTRANSPORTERS (SGLT) --- p.48 / Chapter 3.1 --- Introduction --- p.48 / Chapter 3.2 --- Materials --- p.49 / Chapter 3.3 --- Methods and Methods --- p.52 / Chapter 3.3.1 --- In vitro model for screening of SGLT inhibitor --- p.52 / Chapter 3.3.1.1 --- Preparation of hSGLT1 and hSGLT2 Plasmid --- p.52 / Chapter 3.3.1.2 --- Transient Transfection of SGLT1 or SGLT2 clone --- p.53 / Chapter 3.3.1.3 --- Detection of mRNA expression level by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) --- p.54 / Chapter 3.3.1.4 --- Development of SGLT1 or SGLT2 stable cell lines --- p.56 / Chapter 3.3.1.5 --- Results --- p.56 / Chapter 3.3.2 --- Cell proliferation assay (MTT assay) --- p.57 / Chapter 3.3.2.1 --- Methods --- p.57 / Chapter 3.3.2.2 --- Results --- p.58 / Chapter 3.3.3 --- Uptake Assay of ¹⁴C-α-methyl-D-glucopyranoside (¹⁴C-AMG) in cultured COS-7 cells expressing SGLT1 or SGLT2 --- p.63 / Chapter 3.3.3.1 --- Methods --- p.63 / Chapter 3.3.3.2 --- Screening Results of Effective Chinese Herbs/Natural Products --- p.64 / Chapter 3.4 --- Discussion --- p.83 / Chapter CHAPTER 4 --- FRACTIONATION OF SCHISANDRAE CHINENSIS FRUCTUS --- p.86 / Chapter 4.1 --- Introduction --- p.86 / Chapter 4.2 --- Organic Extraction of Schisandrae Chinensis Fructus --- p.86 / Chapter 4.2.1 --- Material and Methods --- p.86 / Chapter 4.2.2 --- Result --- p.86 / Chapter 4.3 --- Bioassay-guided Fractionation of Ethanolic Extract of Schisandrae Chinensis Fructus --- p.87 / Chapter 4.3.1 --- Materials --- p.87 / Chapter 4.3.2 --- Methods --- p.87 / Chapter 4.3.2 --- Results --- p.89 / Chapter 4.4 --- ¹⁴C-α-methyl-D-glucopyranoside (¹⁴C-AMG) Uptake Assay of fractions in cultured COS-7 cells expressing SGLT1 or SGLT2 --- p.92 / Chapter 4.4.1 --- Methods --- p.92 / Chapter 4.4.2 --- Results --- p.93 / Chapter 4.5 --- Characterization of F8 of Schisandrae chinensis fructus using Ultra Performance Liquid Chromatography (UPLC) --- p.98 / Chapter 4.5.1 --- Introduction --- p.98 / Chapter 4.5.2 --- Materials and Methods --- p.98 / Chapter 4.5.3 --- UPLC chromatograms --- p.99 / Chapter 4.6 --- Characterization of F8 using Liquid Chromatography/Mass Spectrometry-Mass Spectrometry (LC/MS-MS) --- p.101 / Chapter 4.6.1. --- Materials --- p.101 / Chapter 4.6.2 --- Methods --- p.102 / Chapter 4.6.3 --- Results --- p.103 / Chapter 4.7 --- ¹⁴C-α-methyl-D-glucopyranoside (¹⁴C-AMG) Uptake Assay of three chemical standards in cultured COS-7 cells expressing SGLT1 or SLGT2 --- p.108 / Chapter 4.7.1 --- Methods --- p.108 / Chapter 4.7.2 --- Results --- p.108 / Chapter 4.8 --- Discussion --- p.111 / Chapter CHAPTER 5 --- IN VIVO STUDIES OF THE ANTI-DIABETIC EFFECT OF SELECTED TRADITIONAL CHINESE HERBS AND NATURAL PRODUCTS IN TYPE 2 DIABETIC RAT MODEL --- p.114 / Chapter 5.1 --- Introduction --- p.114 / Chapter 5.1.1 --- Diabetic Animal Models --- p.114 / Chapter 5.2 --- In vivo Study Tests --- p.117 / Chapter 5.2.1 --- Introduction --- p.117 / Chapter 5.2.2 --- Animals --- p.117 / Chapter 5.2.3 --- Methods --- p.118 / Chapter 5.2.4 --- Results --- p.120 / Chapter 5.3 --- Discussion --- p.125 / Chapter CHAPTER 6 --- GENERAL DISCUSSION --- p.128 / Chapter 6.1 --- Importance of SGLT --- p.128 / Chapter 6.2 --- Current developed SGLT 2 Inhibitors --- p.130 / Chapter 6.3 --- Importance and Treatment of DM by TCMs --- p.132 / Chapter 6.4 --- Screening and Developing drugs from Traditional Chinese medicinal plants --- p.134 / Chapter 6.5 --- Limitations and Improvements --- p.136 / Chapter 6.6 --- Future Works --- p.137 / Chapter 6.7 --- Conclusions --- p.139 / REFERENCES --- p.141
27

The possible mechanisms of peroxisome proliferator-activatedreceptor (PPAR) agonists in controlling graft rejection

Cai, Qi, 蔡綺 January 2005 (has links)
published_or_final_version / abstract / Surgery / Master / Master of Philosophy
28

Combined therapy with oral hypoglycaemic agents compared to insulin therapy alone in Hong Kong Chinese patients with non-insulin dependent diabetes mellitus.

January 1997 (has links)
by Lynn Wah Wong Tsang. / Consent form in Chinese. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 127-145). / Declaration --- p.i / Acknowledgments --- p.ii / Table of Contents --- p.iii / List of Tables --- p.vii / List of Figures --- p.x / List of Appendix --- p.xi / Chapter CHAPTER1 --- INTRODUCTION / Chapter 1.1 --- General Introduction --- p.2 / Chapter 1.2 --- Literature Review --- p.6 / Chapter 1.2.1 --- Classifications of Diabetes Mellitus --- p.6 / Chapter 1.2.2 --- Diagnostic Criteria of Diabetes Mellitus --- p.6 / Chapter 1.2.3 --- Characteristics of NIDDM --- p.9 / Chapter 1.2.4 --- Epidemiology of NIDDM --- p.13 / Chapter 1.2.5 --- Pathophysiology of NIDDM --- p.16 / Chapter 1.2.6 --- Determinants and Causes of NIDDM --- p.16 / Chapter 1.2.7 --- Etiology and Risk Factors ofNIDDM --- p.20 / Chapter 1.2.7.1 --- Genetic Factors --- p.20 / Chapter 1.2.7.2 --- Environmental Factors --- p.20 / Chapter 1.2.7.2.1 --- Physical Inactivity --- p.20 / Chapter 1.2.7.3 --- Body Weight and Fat Distribution --- p.21 / Chapter 1.2.7.4 --- Gestational Diabetes Mellitus --- p.22 / Chapter 1.2.7.5 --- Impaired Glucose Tolerance --- p.23 / Chapter 1.2.8 --- Complications --- p.23 / Chapter 1.2.9 --- Oral hypoglycaemic agents --- p.25 / Chapter 1.2.9.1 --- Insulin Secretagogues --- p.25 / Chapter 1.2.9.2 --- Metformin --- p.26 / Chapter 1.2.9.3 --- Apha-Glucosidase Inhibitors --- p.26 / Chapter 1.2.9.4 --- Insulin Sensitizers --- p.27 / Chapter 1.2.10 --- Oral Hypoglycaemic Agent Failure --- p.27 / Chapter 1.2.11 --- Use of Insulin in NIDDM --- p.28 / Chapter 1.2.12 --- Combination Therapy --- p.30 / Chapter CHAPTER2 --- RESEARCH DESIGN AND METHODS / Chapter 2.1 --- Study Protocol --- p.37 / Chapter 2.2 --- Objectives --- p.37 / Chapter 2.3 --- Overall Design --- p.38 / Chapter 2.3.1 --- Selection of Patients --- p.38 / Chapter 2.3.1.1 --- Inclusion Criteria --- p.38 / Chapter 2.3.1.2 --- Exclusion Criteria --- p.40 / Chapter 2.3.2 --- Recruitment Period --- p.40 / Chapter 2.3.2.1 --- Screening Period --- p.40 / Chapter 2.3.2.2 --- Pre-Run-In Period --- p.41 / Chapter 2.3.3 --- Run-in Period --- p.42 / Chapter 2.3.3.1 --- Stabilization --- p.43 / Chapter 2.3.3.2 --- Randomization --- p.44 / Chapter 2.3.3.2.1 --- Combination Group --- p.45 / Chapter 2.3.3.2.2 --- Insulin Group --- p.47 / Chapter 2.3.4 --- Evaluation Periods --- p.48 / Chapter 2.3.5 --- Study Medications --- p.49 / Chapter 2.3.6 --- Clinical Assessments --- p.50 / Chapter 2.4 --- Withdrawals --- p.50 / Chapter 2.5 --- Investigations --- p.51 / Chapter 2.6 --- Analytical Methods --- p.52 / Chapter 2.7 --- Statistical Analysis --- p.53 / Chapter CHAPTER3 --- RESULTS / Chapter 3.1 --- Study Population --- p.56 / Chapter 3.2 --- Randomization --- p.58 / Chapter 3.3 --- Study Results --- p.63 / Chapter 3.3.1 --- Indices of Glycaemic Control and Lipids --- p.63 / Chapter 3.3.1.1 --- Glucose Values --- p.63 / Chapter 3.3.1.2 --- Glucosylated Haemoglobin and Glycated Plasma Protein Concentration --- p.64 / Chapter 3.3.1.2.1 --- Glucosylated Haemoglobin --- p.64 / Chapter 3.3.1.2.2 --- Glycated Plasma Protein Concentration --- p.68 / Chapter 3.3.1.3 --- Plasma Lipid Concentrations --- p.69 / Chapter 3.3.2 --- Clinical Determinants --- p.70 / Chapter 3.3.2.1 --- Blood Pressure Measurements --- p.70 / Chapter 3.3.2.2 --- Body Weight Evaluations --- p.71 / Chapter 3.3.3 --- Insulin Types Used --- p.76 / Chapter 3.3.4 --- Insulin Dosage Requirements --- p.76 / Chapter 3.3.5 --- Subjective Well Being and Acceptability of Insulin Injection --- p.78 / Chapter 3.3.6 --- Hypoglycaemic Events --- p.85 / Chapter 3.3.7 --- Subsequent Study Discontinuation --- p.85 / Chapter 3.3.8 --- Responders versus no Responders --- p.86 / Chapter CHAPTER4 --- GENERAL DISCUSSION / Chapter 4.1 --- Summary of Results --- p.92 / Chapter 4.2 --- Acute and Long Term Effects of --- p.101 / Combination Therapy / APPENDIX --- p.111 / REFERENCES --- p.127 / Chapter 2 --- Abstracts summarized recent data not incorporated in this thesis --- p.147
29

Novel pharmaceutical approaches to regulate glucose homeostasis

Sundbom, Maj, January 2010 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2010. / Härtill 3 uppsatser.
30

Effects of plant sterols on plasma lipid profiles, glycemic control of hypercholesterolemic individuals with and without type 2 diabetes

Lau, Vivian Wai Yan, 1977- January 2003 (has links)
Plant sterols (PS) are effective in reducing plasma lipid concentrations, however, few studies have examined their cholesterol lowering effects in type 2 diabetics. The objective was to assess whether PS consumption alters blood lipid profile in hypercholesterolemic subjects with and without type 2 diabetes. Fifteen control subjects (age = 55.1 +/- 8.5 yr and BMI = 26.9 +/- 3.0kg/m2) and fourteen diabetic subjects (age = 54.5 +/- 6.7 yr and BMI = 30.2 +/- 3.0kg/m2) participated in a double-blinded, randomized, crossover, placebo-controlled feeding trial. The Western diet included either 1.8g/d of PS or cornstarch placebo each provided over 21 d separated by a 28 d washout period. Subjects consumed only foods prepared in Mary Emily Clinical Nutrition Research Unit of McGill University. Total cholesterol (TC) decreased (p < 0.05) from baseline with PS for control and diabetic subjects by 9.7% and 13.6%, respectively. TC decreased (P < 0.05) from baseline with placebo for control and diabetic subjects by 10.9% and 11.6%, respectively. Non high density lipoprotein cholesterol (non-HDL-C) decreased (p < 0.05) from baseline with PS for diabetic subjects by 18.5%. Low density lipoprotein cholesterol (LDL-C) levels were reduced (p < 0.05) from baseline with PS for control and diabetic subjects by 14.9% and 29.8%, respectively. The reduction of LDL-C due to PS alone is greater with type 2 diabetics. There were no significant changes in HDL-C and TG across diets or treatments. It is thus concluded that PS consumption with diet enhances non-HDL-C and LDL-C reduction compared with diet alone in hypercholesterolemic individuals with and without type 2 diabetes. Demonstration for the first time that PS alone are more efficacious in lowering LDL-C and non-HDL-C in diabetic individuals compared to non-diabetics confirm the beneficial effects of PS to help prevent cardiovascular disease (CVD) for this high risk population.

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