Spelling suggestions: "subject:"angiotensin"" "subject:"angiotensina""
41 |
Oestrogen and atherosclerosisDennis, Maxine Elizabeth January 2009 (has links)
[Truncated abstract] Our understanding of the actions of oestrogen on the vasculature has recently been questioned following the results of large clinical trials revealing a negative effect of hormone replacement therapy (HRT) on cardiovascular disease (CVD) risk amongst postmenopausal women. It is important to determine how a hormone with numerous positive effects on intermediate pathways of atherosclerosis fails to offer cardioprotection. Further investigation into the actions of oestrogen in the vasculature may add to our current understanding of the pathogenesis of atherosclerosis and oestrogen biology. The primary aim of this thesis was to investigate involvement of the oestrogen receptors (ERs) in atherosclerotic CVD and to provide further insight into the actions of oestrogen on the vasculature by studying the actions of oestrogen on the regulation of an oestrogen-responsive gene within human vascular cells. Following confirmation of ERa and ERß expression at the RNA and protein level in human aorta sections, correlations of receptor expression with age and atherosclerosis were examined. Significantly strong negative relationships of ERa, androgen receptor (AR), and progesterone receptor (PR) with age in both males and females were detected. No trend was detected between ERß expression and age. These findings suggest that the receptor-mediated actions of hormones in the vasculature may change with age. Further, this thesis compared for the first time sex hormone receptor expression in normal and adjacent atherosclerotic aortic tissue providing a critical assessment of receptor differences due to atherosclerosis. Results revealed reductions of all hormone receptors in early atherosclerotic versus normal aorta tissue. ... These results suggest that the 3'-UTR SNPS may have more of an influence on carotid thickening when oestrogen levels are lower, suggesting the importance of both genetic variation of the ERß gene and oestrogen status on carotid thickening. Finally, this was the first study to investigate oestrogen-induced regulation of angiotensinogen (AGT), a candidate gene for CVD, in human vascular cells. Oestrogen influenced AGT transcription in a cell specific manner. The overall influence of oestrogen on AGT transcription in the vasculature is unknown. This thesis adds to the knowledge of oestrogen and atherosclerosis by suggesting the involvement of the sex hormone receptors (ERa, ERß, PR and AR) in atherosclerosis, presenting ERß as a potentially important candidate gene for atherosclerosis, revealing interactions between estrogen status and associations of ERß SNPs with carotid thickening, and demonstrating vascular cell-specific actions of oestrogen on the regulation of a candidate gene for CVD. These factors may have contributed to the lack of cardio-protection following HRT, as revealed by large clinical trials.
|
42 |
Effects of hypertension and dietary salt on myogenic activity in the microcirculation possible roles of nitric oxide and angiotensin II /Nurkiewicz, Timothy Robert, January 1999 (has links)
Thesis (Ph. D.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xvi, 200 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references.
|
43 |
Role of angiotensin in the vascular response to chronic renal tubular obstructionCarmines, Pamela Kay January 1982 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
|
44 |
Elucidating the Trafficking and Regulation of CaV1.2 in Adult Mouse CardiomyocytesBorowik, Sergej January 2024 (has links)
Calcium (Ca²⁺) influx through Caᵥ1.2 channels mediates cardiac excitation-contraction coupling, tunes cardiac action potential duration and excitability, and regulates cardiomyocytes’ (CM) gene expression. Mechanisms regulating the sub-cellular localization, trafficking, and dynamics of surface Caᵥ1.2 in ventricular CMs are poorly understood though these are critical determinants of cardiac function.
To gain new insights into Caᵥ1.2 organization, dynamics, and regulation at the CM surface we generated transgenic mice expressing an αMHC controlled cardiac-specific, dihydropyridine (DHP)- resistant α₁_ᴄ construct, tagged at the N-terminus with FLAG and HA epitopes, at the C- terminus with YFP, a 13-residue bungarotoxin binding site (BBS) inserted into in the third extracellular loop of domain II, and mutations that prevent cleavage of the C-terminus. We found robust inducible expression of DHP-resistant FLAG-HA-BBS-α₁_ᴄ-YFP in the heart that targeted to dyadic junctions, generated nisoldipine-resistant Ca²⁺ currents, supported cardiac excitation-contraction coupling, and was normally up-regulated by β-adrenergic activation with isoproterenol. Incubating transgenic CMs with AlexaFluor₆₄₇-conjugated α- bungarotoxin (BTX₆₄₇) enabled selective labeling of surface BBS-tagged Caᵥ1.2 channels.
We used total internal fluorescence (TIRF) microscopy to investigate the spatiotemporal organization and dynamics of surface Caᵥ1.2 channels. Similar to endogenous Caᵥ1.2, transgenic α1C-YFP forms clusters with exponentially distributed sizes at the cell surface. A flow cytometry-based optical pulse-chase assay revealed surface Caᵥ1.2 channels in adult cardiomyocytes fully turn over within two hours. Application of angiotensin II (Ang II) decreased transgenic Caᵥ1.2 surface density and this effect was blocked by the selective Ang II receptor type I (AT1R) blocker losartan. Application of losartan by itself increased Caᵥ1.2 surface density, suggesting the potential presence of constitutively active Ang II receptors in adult CMs. Our results provide new insights into spatiotemporal organization, dynamics, and regulation of Caᵥ1.2 channels in adult CMs and introduce an approach that can be widely applied to elucidate spatiotemporal dynamics of cardiac ion channels and membrane proteins.
|
45 |
Efeito da angiotensina-(1-7) no fluxo reabsortivo de bicarbonato (JHCO3-) e na concentração citosólica de cálcio ([Ca2+]i): estudo por microperfusão tubular proximal, in vivo. / Effect of angiotensin-(1-7) on the net reabsortive flow of bicarbonate and on calcium cytosolic concentration: study by in vivo proximal tubular microperfusion.Branco, Regiane Cardoso Castelo 23 April 2012 (has links)
O estudo avaliou os efeitos agudos da Ang-(1-7) na reabsorção de bicarbonato (JHCO3-) no túbulo proximal cortical de rato, in vivo, medindo o pH intratubular pelo microeletródio sensível a H+. O JHCO3- controle é 2,84 ± 0,08 nmol. cm-2. s-1 (49), a Ang-(1-7; 10-12 ou 10-9 M) o reduz (35 ou 61 %) e a Ang-(1-7; 10-6 M) o eleva (56 %). A inibição do receptor Mas (por A779) eleva o JHCO3- (30 %), abole o efeito inibidor da Ang-(1-7), mas não afeta seu efeito estimulador. A inibição do NHE3 (por S3226) diminui o JHCO3- (45 %), não altera o efeito inibidor da Ang-(1-7), mas transforma seu efeito estimulador em inibidor. A concentração de cálcio citosólico ([Ca2+]i), medida pelo FURA-2-AM, controle é 100 ± 2,47 nM (35) e a Ang-(1-7; 10-12, 10-9 ou 10-6 M) a aumenta (152, 103 ou 53 %) transientemente (3 min). A inibição do receptor Mas aumenta a [Ca2+]i (26 %), mais inibe o efeito estimulador de todas as doses de Ang-(1-7). Os resultados indicam que o efeito bifásico dose-dependente da Ang-(1-7) sobre o JHCO3- no túbulo proximal é via receptor Mas e isoforma NHE3 e sugerem estimulação desse trocador por moderado aumento da [Ca2+]i na presença de Ang-(1-7; 10-6 M) e sua inibição por pronunciado aumento da [Ca2+]i na vigência de Ang-(1-7; 10-12 ou 10-9 M). / The action of Ang-(1-7) on bicarbonate reabsorption (JHCO3-) was evaluated in vivo middle proximal tubule of rat kidney, using H ion-sensitive microelectrodes. The control JHCO3- is 2,84 ± 0.08 nmol. cm-2. s-1 (49), Ang-(1-7; 10-12 or 10-9 M) decreases it (35 and 61 %) but Ang-(1-7; 10-6 M) increased it (56 %). A779 (an Ang-(1-7) receptor Mas antagonist) increases the JHCO3- (30 %), prevents the inhibitory effect of Ang-(1-7) and does not affect the stimulatory effect of Ang-(1-7). S3226 (10-6 M; an inhibitor of NHE3) decreases the JHCO3- (45 %), does not affect the inhibitory effect of Ang-(1-7) and changes its stimulatory effect on an inhibitory effect. The control cytosolic free calcium ([Ca2+]i), monitored by FURA-2-AM, is 100 ± 2,47 nM (35) and Ang-(1-7; 10-12, 10-9 or 10-6 M) causes a transient (3 min) increase of it (152, 103 or 53 %). A779 increases the [Ca2+]i (26 %) but impaired the stimulatory effect of Ang-(1-7). Our results indicate the biphasic dose-dependent effect of Ang-(1-7) on JHCO3- in proximal tubule is mediated via Mas receptor and NHE3 and are compatible with stimulation of this exchanger by a moderate increase in [Ca2+]i in the presence of Ang-(1-7, 10-6 M), and its inhibition by large increase in [Ca2+]i with Ang-(1-7, 10-12 or 10-9 M).
|
46 |
Losartana e hidralazina previnem o acúmulo arterial de lípides induzido pela restrição alimentar crônica de sódio em animais hipertensos e hiperlipidêmicos / Aortic lipid infiltration in renovascular hypertensive hyperlipidemic mice elicited by dietary sodium chloride restriction improves by losartan and hydralazineFusco, Fernanda Bueno 04 May 2015 (has links)
A restrição alimentar de cloreto de sódio prejudica o perfil de lípides plasmáticos e a sensibilidade à insulina, favorecendo a aterosclerose em modelos animais dislipidêmicos. A hiperlipidemia e a ativação do sistema renina-angiotensina-aldosterona, isolados ou conjuntamente, estimulam a aterogênese. O objetivo deste estudo foi investigar a influência da restrição crônica de cloreto de sódio na dieta sobre a aterogênese utilizando-se camundongos hiperlipidêmicos (modelo de estudo para aterosclerose) e com hipertensão renovascular. Camundongos knockout para o receptor de lipoproteína de densidade baixa (LDLR KO) e com hipertensão renovascular cirurgicamente induzida (hipertensão dependente de angiotensina II endógena; 2-kidney, 1-clip; 2K1C), tratados ou não com fármacos anti-hipertensivos (losartana ou hidralazina), foram alimentados ad libitum com ração contendo baixa concentração de sódio (HS) (0,15% NaCl) ou ração com concentração padrão de sódio (NS) (1,27% NaCl) a partir do desmame até completarem 5 meses de idade. Camundongos hipertensos submetidos à restrição de sódio apresentaram maior concentração plasmática de colesterol total (CT) e triglicérides (TG), quando comparados aos animais alimentados com dieta NS, confirmando nosso estudo anterior com camundongos normotensos. Os camundongos hipertensos alimentados com dieta HS apresentaram maior infiltração de lípides na parede do arco aórtico quando comparados aos animais NS, apesar da redução da pressão arterial (PA) obtida com a restrição de sódio. A dieta LS não alterou o peso corpóreo e o hematócrito dos animais, exceto em relação aos camundongos tratados com losartana os quais apresentaram discreta redução de hematócrito e das concentrações plasmáticas de TG e de ácidos graxos livres (AGL) justificando, provavelmente, a menor infiltração de lípides no arco aórtico destes animais. Quando comparados aos animais normotensos alimentados com dieta HS, os camundongos hipertensos tratados com losartana ou hidralazina apresentaram menor infiltração lipídica na vasculatura, sugerindo que mecanismos benéficos dos fármacos anti-hipertensivos sobre o metabolismo possam ter superado o efeito destes fármacos sobre a PA. Este estudo pode contribuir no esclarecimento dos mecanismos de ação dos fármacos anti-hipertensivos sobre a aterogênese e nas questões conflitantes em relação à restrição alimentar de sódio, hipertensão arterial, dislipidemia e doença cardiovascular prematura / This study sought to investigate the influence of chronic dietary sodium chloride restriction on atherogenesis utilizing renovascular hypertensive hyperlipidemic mice. Low density lipoprotein receptor knockout (LDLR KO) mice with renovascular hypertension (endogenous angiotensin II-dependent hypertension; 2-kidney, 1-clip - 2K1C), treated or not with antihypertensive drugs losartan or hydralazine, were fed ad libitum either a low-sodium diet (LS) (0.15% NaCl) or a normal-sodium chow (NS) (1.27% NaCl) from weaning to 5 months of age. Hypertensive mice showed higher plasma total cholesterol (TC) and triglyceride (TG) concentrations on LS than on NS confirming our previous study on normotensive mice. In hypertensive mice aortic lipid infiltration was much greater on LS than on NS in spite of the reduction of the blood pressure (BP) attained by LS. LS did not modify the mouse body weight and hematocrit, however the latter was slightly but significantly diminished in the losartan-treated hypertensive group. In hypertensive mice plasma TG and nonesterified fatty acids (NEFA) levels were significantly reduced by losartan seemingly explaining the most significant of all reduction of aortic lipid infiltration reached in this group. Hypertensive mice fed LS diet either on losartan or hydralazine treatment had lower aortic lipid infiltration, suggesting that other beneficial metabolic actions of these drugs must have overcome their effect on BP, as compared to normotensive mice on LS diet. This study sheds light on mechanisms of action of antihypertensive drugs in atherosclerosis and on the conflicting issues regarding dietary sodium restriction on hypertension, dyslipidemia and premature cardiovascular disease in human populations
|
47 |
Losartana e hidralazina previnem o acúmulo arterial de lípides induzido pela restrição alimentar crônica de sódio em animais hipertensos e hiperlipidêmicos / Aortic lipid infiltration in renovascular hypertensive hyperlipidemic mice elicited by dietary sodium chloride restriction improves by losartan and hydralazineFernanda Bueno Fusco 04 May 2015 (has links)
A restrição alimentar de cloreto de sódio prejudica o perfil de lípides plasmáticos e a sensibilidade à insulina, favorecendo a aterosclerose em modelos animais dislipidêmicos. A hiperlipidemia e a ativação do sistema renina-angiotensina-aldosterona, isolados ou conjuntamente, estimulam a aterogênese. O objetivo deste estudo foi investigar a influência da restrição crônica de cloreto de sódio na dieta sobre a aterogênese utilizando-se camundongos hiperlipidêmicos (modelo de estudo para aterosclerose) e com hipertensão renovascular. Camundongos knockout para o receptor de lipoproteína de densidade baixa (LDLR KO) e com hipertensão renovascular cirurgicamente induzida (hipertensão dependente de angiotensina II endógena; 2-kidney, 1-clip; 2K1C), tratados ou não com fármacos anti-hipertensivos (losartana ou hidralazina), foram alimentados ad libitum com ração contendo baixa concentração de sódio (HS) (0,15% NaCl) ou ração com concentração padrão de sódio (NS) (1,27% NaCl) a partir do desmame até completarem 5 meses de idade. Camundongos hipertensos submetidos à restrição de sódio apresentaram maior concentração plasmática de colesterol total (CT) e triglicérides (TG), quando comparados aos animais alimentados com dieta NS, confirmando nosso estudo anterior com camundongos normotensos. Os camundongos hipertensos alimentados com dieta HS apresentaram maior infiltração de lípides na parede do arco aórtico quando comparados aos animais NS, apesar da redução da pressão arterial (PA) obtida com a restrição de sódio. A dieta LS não alterou o peso corpóreo e o hematócrito dos animais, exceto em relação aos camundongos tratados com losartana os quais apresentaram discreta redução de hematócrito e das concentrações plasmáticas de TG e de ácidos graxos livres (AGL) justificando, provavelmente, a menor infiltração de lípides no arco aórtico destes animais. Quando comparados aos animais normotensos alimentados com dieta HS, os camundongos hipertensos tratados com losartana ou hidralazina apresentaram menor infiltração lipídica na vasculatura, sugerindo que mecanismos benéficos dos fármacos anti-hipertensivos sobre o metabolismo possam ter superado o efeito destes fármacos sobre a PA. Este estudo pode contribuir no esclarecimento dos mecanismos de ação dos fármacos anti-hipertensivos sobre a aterogênese e nas questões conflitantes em relação à restrição alimentar de sódio, hipertensão arterial, dislipidemia e doença cardiovascular prematura / This study sought to investigate the influence of chronic dietary sodium chloride restriction on atherogenesis utilizing renovascular hypertensive hyperlipidemic mice. Low density lipoprotein receptor knockout (LDLR KO) mice with renovascular hypertension (endogenous angiotensin II-dependent hypertension; 2-kidney, 1-clip - 2K1C), treated or not with antihypertensive drugs losartan or hydralazine, were fed ad libitum either a low-sodium diet (LS) (0.15% NaCl) or a normal-sodium chow (NS) (1.27% NaCl) from weaning to 5 months of age. Hypertensive mice showed higher plasma total cholesterol (TC) and triglyceride (TG) concentrations on LS than on NS confirming our previous study on normotensive mice. In hypertensive mice aortic lipid infiltration was much greater on LS than on NS in spite of the reduction of the blood pressure (BP) attained by LS. LS did not modify the mouse body weight and hematocrit, however the latter was slightly but significantly diminished in the losartan-treated hypertensive group. In hypertensive mice plasma TG and nonesterified fatty acids (NEFA) levels were significantly reduced by losartan seemingly explaining the most significant of all reduction of aortic lipid infiltration reached in this group. Hypertensive mice fed LS diet either on losartan or hydralazine treatment had lower aortic lipid infiltration, suggesting that other beneficial metabolic actions of these drugs must have overcome their effect on BP, as compared to normotensive mice on LS diet. This study sheds light on mechanisms of action of antihypertensive drugs in atherosclerosis and on the conflicting issues regarding dietary sodium restriction on hypertension, dyslipidemia and premature cardiovascular disease in human populations
|
48 |
Efeito da angiotensina-(1-7) no fluxo reabsortivo de bicarbonato (JHCO3-) e na concentração citosólica de cálcio ([Ca2+]i): estudo por microperfusão tubular proximal, in vivo. / Effect of angiotensin-(1-7) on the net reabsortive flow of bicarbonate and on calcium cytosolic concentration: study by in vivo proximal tubular microperfusion.Regiane Cardoso Castelo Branco 23 April 2012 (has links)
O estudo avaliou os efeitos agudos da Ang-(1-7) na reabsorção de bicarbonato (JHCO3-) no túbulo proximal cortical de rato, in vivo, medindo o pH intratubular pelo microeletródio sensível a H+. O JHCO3- controle é 2,84 ± 0,08 nmol. cm-2. s-1 (49), a Ang-(1-7; 10-12 ou 10-9 M) o reduz (35 ou 61 %) e a Ang-(1-7; 10-6 M) o eleva (56 %). A inibição do receptor Mas (por A779) eleva o JHCO3- (30 %), abole o efeito inibidor da Ang-(1-7), mas não afeta seu efeito estimulador. A inibição do NHE3 (por S3226) diminui o JHCO3- (45 %), não altera o efeito inibidor da Ang-(1-7), mas transforma seu efeito estimulador em inibidor. A concentração de cálcio citosólico ([Ca2+]i), medida pelo FURA-2-AM, controle é 100 ± 2,47 nM (35) e a Ang-(1-7; 10-12, 10-9 ou 10-6 M) a aumenta (152, 103 ou 53 %) transientemente (3 min). A inibição do receptor Mas aumenta a [Ca2+]i (26 %), mais inibe o efeito estimulador de todas as doses de Ang-(1-7). Os resultados indicam que o efeito bifásico dose-dependente da Ang-(1-7) sobre o JHCO3- no túbulo proximal é via receptor Mas e isoforma NHE3 e sugerem estimulação desse trocador por moderado aumento da [Ca2+]i na presença de Ang-(1-7; 10-6 M) e sua inibição por pronunciado aumento da [Ca2+]i na vigência de Ang-(1-7; 10-12 ou 10-9 M). / The action of Ang-(1-7) on bicarbonate reabsorption (JHCO3-) was evaluated in vivo middle proximal tubule of rat kidney, using H ion-sensitive microelectrodes. The control JHCO3- is 2,84 ± 0.08 nmol. cm-2. s-1 (49), Ang-(1-7; 10-12 or 10-9 M) decreases it (35 and 61 %) but Ang-(1-7; 10-6 M) increased it (56 %). A779 (an Ang-(1-7) receptor Mas antagonist) increases the JHCO3- (30 %), prevents the inhibitory effect of Ang-(1-7) and does not affect the stimulatory effect of Ang-(1-7). S3226 (10-6 M; an inhibitor of NHE3) decreases the JHCO3- (45 %), does not affect the inhibitory effect of Ang-(1-7) and changes its stimulatory effect on an inhibitory effect. The control cytosolic free calcium ([Ca2+]i), monitored by FURA-2-AM, is 100 ± 2,47 nM (35) and Ang-(1-7; 10-12, 10-9 or 10-6 M) causes a transient (3 min) increase of it (152, 103 or 53 %). A779 increases the [Ca2+]i (26 %) but impaired the stimulatory effect of Ang-(1-7). Our results indicate the biphasic dose-dependent effect of Ang-(1-7) on JHCO3- in proximal tubule is mediated via Mas receptor and NHE3 and are compatible with stimulation of this exchanger by a moderate increase in [Ca2+]i in the presence of Ang-(1-7, 10-6 M), and its inhibition by large increase in [Ca2+]i with Ang-(1-7, 10-12 or 10-9 M).
|
49 |
Papel da imunidade inata na doença renal crônica que se segue ao tratamento temporário com uma sobrecarga de adenina na dieta / The role of innate immunity in chronic kidney disease following the treatment with a temporary overload dietary adenineMoreira, Gizely Cristina da Silva 08 March 2017 (has links)
O excesso de adenina na dieta (ADE) promove precipitação intrabular de cristais, levando a uma nefrite intersticial progressiva com perda de função renal. Estudo recente demonstrou que esse processo requer ativação do sistema NF-kB. No presente estudo investigamos o possível envolvimento de outros componentes da imunidade inata, além do NF-kB. Verificamos também a hipótese de que a nefropatia associada aos cristais continua a progredir mesmo depois de cessada a sobrecarga de adenina. Foram estudados ratos Munich-Wistar machos e adultos sem tratamento (C) ou recebendo 0.5% de ADE na dieta. Após 1 semana, a ADE foi removida da dieta e os animais foram seguidos por 4 ou 24 semanas. A administração de ADE por 1 semana promoveu uma inflamação intersticial aguda, com perda de função renal, alteração da pressão caudal, sem alterações glomerulares. Os mediadores da imunidade inata, como TLR2, TLR4, inflamassoma NLRP3, IL1beta e IL-6, apresentaram-se ativados sem, no entanto, ativar o sistema NF-kB. Após cessada a sobrecarga de ADE, a inflamação persistiu, com infiltração por macrófagos, expressão elevada de AngII, deposição progressiva de colágeno e, na fase mais tardia, glomeruloesclerose, caracterizando um processo inflamatório crônico, autônomo, que não contou com a participação do eixo NLR/IL1beta. Em contraste, o sistema NF-kB foi ativado, sendo um dos possíveis estímulos a produção intra-renal de AngII. Dois mecanismos patogênicos podem ser identificados neste estudo: 1) agudo, associado à ativação do eixo NLR-IL1beta; 2) crônico, associado à produção de AngII renal e à ativação do sistema NF-kB / Excess adenine in the diet (ADE) promotes intratubular crystal precipitation, leading to progressive interstitial nephritis and loss of renal function. A recent study has shown that this process requires activation of the NF-kB system. In the present study we investigated the possible involvement of other components of innate immunity, in addition to NF-kB, as well as whether nephropathy associated with excess adenine continues to progress even after dietary cessation. Male Munich-Wistar rats without treatment (C) or receiving 0.5% of ADE in the diet were studied. After 1 week, ADE was removed from the diet and the animals were followed for 4 or 24 weeks. Administration of ADE for 1 week promote acute interstitial inflammation, with loss of renal function, alteration of caudal pressure, without glomerular changes. Mediators of innate immunity, such as TLR2, TLR4, NLRP3 inflamassome, IL1beta and IL-6 , were shown to be activated, with no apparent activation of the NF-kB system. In the late phases of the model, the inflammation persisted, with significant infiltration by macrophages, high expression of AngII, progressive collagen deposition and glomerulosclerosis, characterizing a chronic, autonomic inflammatory process that did not involve the participation of the NLR/IL1beta axis. By contrast, the NF-kB system was activated, with intra-renal AngII production as a possible stimulus. Two mechanisms operated this study: 1) an acute one, associated with activation of the NLR-IL1beta axis; 2) a chronic one, associated with intrarenal AngII production and NF-kB activation
|
50 |
Pharmacogenomics of antihypertensive therapy. / CUHK electronic theses & dissertations collectionJanuary 2012 (has links)
研究背景和目的 / 高血壓和糖尿病是人群中常見的疾病,兩者常共同存在,其共存的病理生理機制非常複雜,其中腎素血管景張素系統功能紊亂起重要作用。多個研究表明血管緊張素轉化晦抑制劑和血管緊張素II 1 型受體阻滯劑通過調節不同基因的表達,發揮其保護心血管和腎臟功能的效用。然而,目前仍缺乏遠兩類藥物影響全基因表達譜的全面調查。因此,本研究應用全基因表達譜晶片技術,檢測分析了高血壓和糖尿病並發的病人在服用安慰劑、雷米普利(ramipril)和替米沙坦(telmisartan)後的全基因表達譜的變化,從而全面評估了血管緊張素轉化臨抑制劑和血管繁張素II 1 型受體阻滯劑對相關基因的轉錄調控作用。 / 方法 / 11 名患有高血壓和糖尿病的病人(男性5 名)在服用安慰劑最少2 星期后,以隨機吹序接受為期各6 星期的雷米普利和替米沙坦治療,並分別在安慰劑期和2 個藥物治療期結束后提取心A 進行全基因表達譜分析。 / 結果 / 與服用安慰劑時的全基因表達譜相比,雷米普利治療后有267 個基因的表達降低, 99 個基因的表達增強。表達差異幅度為-2.0 至1.3 (P < 0.05) 。表達下降的基因主要與血管平滑肌收縮、炎症反應和氧化壓力相關。表達增強的基因主要與心血管炎症反應負調節相關。基因共表達網絡分析表明, 2 個共表達基因組與雷米普利的降血壓作用相闕, 3 個共表達基因組與肥胖相關。 / 與服用安慰劑時的全基因表達譜相比, 替米拉)、坦治療后有55 個基因表達降低, 158 個基因的表達增強。表達差異幅度為-1. 9 至1.3 (P < 0.05) 。表達增強的基因主要與脂質代謝、糖代謝和抗炎症因子作用相關。基因共表達網絡分析表明, 2 個共表達基因組與替米沙坦對24 小時舒張壓負荷量的作用相關, 2 個共表達基因組則與總膽固醇, 低密度脂蛋白膽固醇和C 反應蛋白相關。 / 結論 / 本論文描述了高血壓和2 型糖尿病病患全基因組表達的總體模式及經藥物治療後表達譜的相應改變, 為今後進一步研究腎素血管緊張素系統抑制劑和高血壓、糖尿病發展進程的相互作用提供了方向。 / Background and aim: Pathophysiological mechanisms underpinning the coexistence of hypertension and type 2 diabetes are complex systemic responses involving dysregulation of the renin-angiotensin system (RAS). We conducted this study to investigate the genome wide gene expression changes in patients with both hypertension and diabetes at three treatment stages, including placebo, ramipril and telmisartan. This study aimed to obtain a panoramic view of interactions between gene transcription and antihypertensive therapy by RAS inhibition. / Methods: 11 diabetic patients (S men) with hypertension were treated with placebo for at least 2 weeks followed by 6 weeks randomised crossover treatment with ramipril Smg daily and telmisartan 40mg daily, respectively. Total RNA were extracted from leukocytes at the end of placebo and each treatment period, and were hybridized to the whole transcript microarray. The limma package for R was used to identify differentially expressed genes between placebo and the 2 active treatments. The weighted gene coexpression network analysis (WGCNA) was applied to identify groups of genes (modules) highly correlated to a common biological function in pathogenesis and progression of hypertension and diabetes. / Results: There were 267 genes down-regulated and 99 genes up-regulated with ramipril. Fold changes of gene expression were ranged from -2.0 to 1.3 (P < 0.05). The down-regulated genes were involved in vascular signalling pathways responsible for vascular smooth muscle contraction, inflammation and oxidative stress. The up-regulated genes were associated with negative regulation of cardiovascular inflammation. The WGCNA identified 17 coexpression gene modules related to ramipril. The midnight blue (57 genes, r < -0.44, P < 0.05) and magenta (190 genes, r < -0.44, P < 0.05) modules were significantly correlated to blood pressure differences between placebo and ramipril. / There were 55 genes down-regulated and 158 genes up-regulated with telmisartan. Fold changes of gene expression were ranged from -1.9 to 1.3 (P < 0.05). The down-regulated genes were mainly associated with cardiovascular inflammation and oxidative stress. The up-regulated genes were associated with lipid and glucose metabolism and anti-inflammatory actions. The WGCNA identified 8 coexpression gene modules related to telmisartan. The black (56 genes, r = 0.46, P = 0.03) and turquoise (1340 genes, r = -0.48, P = 0.02) modules were correlated with diastolic blood pressure load. The blue (1027 genes) module was enriched with genes correlated with total cholesterol (r = - 0.52, P = 0.01), LDL-C (r = - 0.58, P = 0.004), and hsCRP (r = -0.57, P = 0.006). The green module (272 genes) was significantly correlated with LDL-C (r = - 0.44, P = 0.04) and hsCRP (r = - 0.59, P = 0.004). / Conclusion: Genome wide gene expression profiling in this study describes the general pattern and treatment responses in patients with hypertension and type 2 diabetes, which suggests future directions for further investigations on the interaction between actions of the RAS blockers and disease progression. / 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. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Deng, Hanbing. / "December 2011." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 198-256). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Declaration --- p.i / Publications --- p.ii / Abstract --- p.iv / 論文摘要 --- p.vi / Acknowledgements --- p.viii / Table of Contents --- p.x / List of tables --- p.xiv / List of figures --- p.xv / List of appendices --- p.xvii / List of abbreviations --- p.xviii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Overview --- p.1 / Chapter 1.2 --- Epidemiology --- p.6 / Chapter 1.2.1 --- Epidemiology of hypertension --- p.9 / Chapter 1.2.2 --- Epidemiology of type 2 diabetes --- p.10 / Chapter 1.3 --- Aetiology --- p.13 / Chapter 1.3.1 --- Ageing --- p.13 / Chapter 1.3.1.1 --- Age-induced artery stiffness --- p.14 / Chapter 1.3.1.2 --- Age-related endothelial dysfunction --- p.14 / Chapter 1.3.2 --- The renin-angiotensin system (RAS) --- p.16 / Chapter 1.3.2.1 --- The local RAS --- p.20 / Chapter 1.3.2.2 --- The RAS and insulin resistance --- p.22 / Chapter 1.3.2.3 --- The RAS and inflammation --- p.26 / Chapter 1.3.2.4 --- The RAS and oxidative stress --- p.28 / Chapter 1.3.3 --- Obesity --- p.31 / Chapter 1.3.3.1 --- Obesity and renin-angiotensin system (RAS) --- p.33 / Chapter 1.3.3.2 --- Obesity and insulin resistance --- p.36 / Chapter 1.3.3.3 --- Obesity and oxidative stress --- p.38 / Chapter 1.3.3.4 --- Obesity and sympathetic nervous system (SNS) --- p.38 / Chapter 1.4 --- Pharmacogenomics of antihypertensive therapy --- p.39 / Chapter 1.4.1 --- Angiotensin-converting enzyme inhibitors (ACEIs) --- p.41 / Chapter 1.4.2 --- Angiotensin II type 1 receptor blockers (ARBs) --- p.43 / Chapter Chapter 2 --- Aim --- p.59 / Chapter Chapter 3 --- Methods --- p.60 / Chapter 3.1 --- Subjects --- p.60 / Chapter 3.1.1 --- Subject recruitment protocol --- p.60 / Chapter 3.1.2 --- Definition of type 2 diabetes --- p.62 / Chapter 3.1.3 --- Definition of obesity --- p.62 / Chapter 3.1.4 --- Definition of dyslipidaemia --- p.63 / Chapter 3.2 --- Study design and procedure --- p.64 / Chapter 3.2.1 --- Blood pressure assessments --- p.65 / Chapter 3.2.2 --- Anthropometric measurements --- p.68 / Chapter 3.2.3 --- Medical history, life style and side effect evaluation --- p.68 / Chapter 3.2.4 --- RNA isolation --- p.68 / Chapter 3.2.5 --- RNA quality assessment --- p.70 / Chapter 3.2.6 --- Oligonucleotide microarrays --- p.71 / Chapter 3.2.7 --- DNA extraction --- p.75 / Chapter 3.2.8 --- Biomedical measurements --- p.76 / Chapter 3.2.8.1 --- Glycosylated haemoglobin Alc (HbA₁c) --- p.77 / Chapter 3.2.8.2 --- Fasting plasma glucose (FP G) --- p.77 / Chapter 3.2.8.3 --- Fasting insulin --- p.77 / Chapter 3.2.8.4 --- Plasma urate --- p.77 / Chapter 3.2.8.5 --- High sensitive C-reactive protein (hsCRP) --- p.78 / Chapter 3.2.8.6 --- Fasting plasma triglycerides (TG) --- p.78 / Chapter 3.2.8.7 --- Fasting plasma cholesterols --- p.78 / Chapter 3.2.8.8 --- Renal and liver functions --- p.78 / Chapter 3.2.8.9 --- Urinary parameters --- p.79 / Chapter 3.3 --- Statistical Analysis --- p.79 / Chapter 3.3.1 --- Statistical analysis of clinical and biomedical data --- p.79 / Chapter 3.3.2 --- Analysis of microarray data --- p.80 / Chapter 3.3.2.1 --- Raw data assessment --- p.80 / Chapter 3.3.2.2 --- Data normalisation --- p.92 / Chapter 3.3.2.3 --- Data filtering --- p.96 / Chapter 3.3.2.4 --- Linear models for assessment of differential expression --- p.96 / Chapter 3.3.2.5 --- Weighted gene coexpression network analysis --- p.101 / Chapter 3.3.2.6 --- Network visualisation and gene ontology analysis --- p.102 / Chapter 3.3.3 --- Sample size calculation --- p.103 / Chapter Chapter 4 --- Results --- p.104 / Chapter 4.1 --- Demographic and biomedical characteristics at baseline --- p.104 / Chapter 4.1.1 --- Hypertension and diabetes status at baseline --- p.108 / Chapter 4.1.2 --- Prevalence of dyslipidaemia --- p.108 / Chapter 4.1.3 --- Prevalence of obesity --- p.109 / Chapter 4.1.4 --- Prevalence of metabolic syndrome --- p.109 / Chapter 4.1.5 --- Inflammation markers --- p.110 / Chapter 4.2 --- Blood pressure response to the RAS blockers --- p.110 / Chapter 4.2.1 --- Clinic blood pressure --- p.110 / Chapter 4.2.2 --- 24-hour ambulatory blood pressure --- p.112 / Chapter 4.3 --- Biomedical characteristics --- p.118 / Chapter 4.4 --- Compliance, side effects and adverse events --- p.120 / Chapter 4.5 --- Gene expression differences between treatments --- p.121 / Chapter 4.5.1 --- Gene expression differences between placebo and ramipril --- p.121 / Chapter 4.5.1.1 --- Expression changes in genes related to regulation of transcription with ramipril --- p.122 / Chapter 4.5.1.2 --- Expression changes with ramipril in genes related to molecular mechanism of cardiovascular changes in hypertension --- p.125 / Chapter 4.5.1.3 --- Expression changes in genes related to blood pressure with ramipril --- p.128 / Chapter 4.5.1.4 --- Expression changes in genes related to fatty acid metabolism with ramipril --- p.130 / Chapter 4.5.1.5 --- Expression changes in genes related to inflammation with ramipril --- p.130 / Chapter 4.5.1.6 --- Expression changes in genes related to oxidative stress with ramipril --- p.133 / Chapter 4.5.1.7 --- Power estimation --- p.133 / Chapter 4.5.2 --- Gene expression differences between placebo and telmisartan --- p.135 / Chapter 4.5.2.1 --- Changes in regulation oftranscription with telmisartan --- p.137 / Chapter 4.5.2.2 --- Expression changes in genes related to glucose metabolism with telmisartan --- p.141 / Chapter 4.5.2.3 --- Expression changes in genes related to lipid metabolism with telmisartan --- p.143 / Chapter 4.5.2.4 --- Expression changes in genes related to inflammation with telmisartan --- p.143 / Chapter 4.5.2.5 --- Power estimation --- p.145 / Chapter 4.5.3 --- WGCNA for comparison between placebo and ramipriI --- p.147 / Chapter 4.5.3.1 --- Midnight blue module and clinical responses to ramipril --- p.152 / Chapter 4.5.3.2 --- Magenta module and blood pressure responses to ramipril --- p.154 / Chapter 4.5.3.3 --- Yellow module and clinical responses to ramipril --- p.158 / Chapter 4.5.3.4 --- Red module and clinical responses to ramipril --- p.161 / Chapter 4.5.3.5 --- Salmon module and clinical responses to ramipril --- p.163 / Chapter 4.5.4 --- WGCNA for comparison between placebo and telmisaItan --- p.168 / Chapter 4.5.4.1 --- Diastolic blood pressure load and gene coexpression modules --- p.168 / Chapter 4.5.4.2 --- Lipids, hsCRP and gene coexpression modules --- p.172 / Chapter Chapter 5 --- Discussion --- p.176 / Chapter 5.1 --- Gene expression changes related to ramipril --- p.177 / Chapter 5.1.1 --- Gene expression changes and blood pressure reduction by ramipri1 --- p.177 / Chapter 5.1.2 --- Gene expression changes and vascular protection by ramipri1 --- p.181 / Chapter 5.1.3 --- Obesity and gene expression changes by ramipril --- p.183 / Chapter 5.2 --- Gene expression changes related to telmisartan --- p.185 / Chapter 5.2.1 --- Blood pressure and coexpressed gene modules with telmisartan --- p.185 / Chapter 5.2.2 --- Lipid metabolism and gene expression changes by telmisartan --- p.187 / Chapter 5.2.3 --- Glucose metabolism and gene expression changes by telmisartan --- p.189 / Chapter 5.2.4 --- hsCRP and gene expression changes by telmisartan --- p.190 / Chapter 5.3 --- Limitations of this study and future directions of research --- p.191 / Chapter Chapter 6 --- Conclusion --- p.194 / References --- p.198 / Appendices --- p.257
|
Page generated in 0.0422 seconds