The insulin resistance syndrome [INSR] is associated with increased cardiovascular risk and affects up to 25% of the Australian population. The mechanism underlying the relationship between the INSR and increased cardiovascular risk is controversial. We postulated that perturbations in the renin-angiotensin system [RAS] and endothelium-derived NO may be implicated in the development of early vascular changes in the INSR. Repeated measurements of arterial stiffness [using digital photoplethysmography] and haemodynamic parameters in response to vasoactive medications were used to demonstrate the functional expression of angiotensin II [Ang II] receptors and NO synthase [NOS]. Ang II acts via two main receptor sub-types: the Ang II type 1 [AT1] and Ang II type 2 [AT2] receptors. The AT1 receptor is central to the development of arterial stiffness and endothelial dysfunction. The role of AT2 receptors in humans is controversial but is postulated to counter-act AT1 receptor mediated effects in diseased vascular beds. We demonstrated increased AT1 and AT2 receptor-mediated effects in small to medium-sized arteries of subjects with early INSR [Chapter 6]. In addition, functional expression of AT2 receptors in adult insulin resistant humans [Chapter 5], but not in healthy volunteers [Chapter 4] was demonstrated. AT1 receptor blockade in subjects with early INSR resulted in improvements in vascular function, with a consequent functional down-regulation of AT2 receptors [Chapter 7]. Functional NOS expression was demonstrated to be increased in subjects with early INSR compared with healthy controls [Chapter 6]. This was postulated to be a homeostatic response to counteract early vascular changes in subjects with early INSR. AT1 receptor blockade in these subjects reduced functional NOS expression [Chapter 8]. In conclusion, patients with early INSR represent a model of early disease where early intervention may be able to reverse the process incited by the initial exposure to multiple cardiovascular risk factors. Early vascular changes in these individuals are mediated at least in part, by increased AT1 receptor activity and/or expression, and may be detected by changes in arterial stiffness indices and non-invasive vascular reactivity studies. There is a compensatory increase in AT2 receptor and NOS expression/activity to counter-act these vascular changes.

The insulin resistance syndrome [INSR] is associated with increased cardiovascular risk and affects up to 25% of the Australian population. The mechanism underlying the relationship between the INSR and increased cardiovascular risk is controversial. We postulated that perturbations in the renin-angiotensin system [RAS] and endothelium-derived NO may be implicated in the development of early vascular changes in the INSR. Repeated measurements of arterial stiffness [using digital photoplethysmography] and haemodynamic parameters in response to vasoactive medications were used to demonstrate the functional expression of angiotensin II [Ang II] receptors and NO synthase [NOS]. Ang II acts via two main receptor sub-types: the Ang II type 1 [AT1] and Ang II type 2 [AT2] receptors. The AT1 receptor is central to the development of arterial stiffness and endothelial dysfunction. The role of AT2 receptors in humans is controversial but is postulated to counter-act AT1 receptor mediated effects in diseased vascular beds. We demonstrated increased AT1 and AT2 receptor-mediated effects in small to medium-sized arteries of subjects with early INSR [Chapter 6]. In addition, functional expression of AT2 receptors in adult insulin resistant humans [Chapter 5], but not in healthy volunteers [Chapter 4] was demonstrated. AT1 receptor blockade in subjects with early INSR resulted in improvements in vascular function, with a consequent functional down-regulation of AT2 receptors [Chapter 7]. Functional NOS expression was demonstrated to be increased in subjects with early INSR compared with healthy controls [Chapter 6]. This was postulated to be a homeostatic response to counteract early vascular changes in subjects with early INSR. AT1 receptor blockade in these subjects reduced functional NOS expression [Chapter 8]. In conclusion, patients with early INSR represent a model of early disease where early intervention may be able to reverse the process incited by the initial exposure to multiple cardiovascular risk factors. Early vascular changes in these individuals are mediated at least in part, by increased AT1 receptor activity and/or expression, and may be detected by changes in arterial stiffness indices and non-invasive vascular reactivity studies. There is a compensatory increase in AT2 receptor and NOS expression/activity to counter-act these vascular changes.

Introdução: A rigidez arterial é um fenômeno complexo caracterizado pela diminuição da complacência vascular frente aos estímulos fisiológicos e patológicos. Semelhantemente a outros fenótipos cardiovasculares, a etiologia da rigidez arterial é modulada por fatores ambientais e genéticos. Levando em consideração a moderada herdabilidade e a característica poligênica do presente fenótipo, torna-se interessante a investigação de marcadores genéticos referentes aos diferentes sistemas envolvidos no remodelamento vascular. Objetivo: Avaliar o impacto dos polimorfismos C242T da subunidade p22phox da NADPH oxidase, G1036C da TXNIP, C609T/T471C da APOE, G1355A da elastina, I/D da ECA e A855G da MMP-9 no fenótipo de rigidez arterial em uma população geral. Métodos: Participaram do estudo 1.663 indivíduos da população geral da cidade de Vitória-ES. O DNA foi extraído a partir de uma amostra de sangue venoso. Posteriormente foram realizadas as genotipagens para as variantes genéticas supracitadas. A rigidez arterial foi avaliada por meio do método da velocidade de onda de pulso (VOP). Resultados: Em relação à VOP, os polimorfismos C242T da subunidade p22phox da NADPH oxidase e G1036C da TXNIP foram signifcativamente associados. Os indivíduos portadores do genótipo TT do polimorfismo C242T da subunidade p22phox (CC+TC=9,8 m/s versus TT=10,1 m/s, p=0,02) e do alelo G do polimorfismo G1036C da TXNIP (CC=9,8 m/s versus CG+GG=10,0 m/s, p=0,03) apresentaram maiores valores da VOP. Entretanto os polimorfismos C609T/T471C da APOE (2=10,0 m/s, 3=9,8 m/s, 4=9,8 m/s, p=0,60), G1355A da elastina (AA=9,8 m/s, GA=9,9 m/s, GG=9,8 m/s, p=0,92), I/D da ECA (DD=9,8 m/s, DI=9,8 m/s, II=9,9 m/s, p=0,53) e A855G da MMP-9 (AA=9,8 m/s, GA=9,8 m/s, GG= 9,8 m/s, p=0,60) não demonstraram tal associação. Somente o genótipo TT do polimorfismo C242T da subunidade p22phox (OR=1,93, p=0,002) apresentou um risco significativamente aumentado para o fenótipo de rigidez arterial. Já os polimorfismos G1036C da TXNIP (OR=1,19, p=0,19), C609T/T471C da APOE (OR=1,14, p=0,33), G1355A da elastina (OR=0,81, p=0,28), I/D da ECA (OR=0,91, p=0,48) e A855G da MMP-9 (OR=1,01, p=0,95) não apresentaram risco. Conclusão: Os polimorfismos C242T da subunidade p22phox da NADPH oxidase e G1036C da TXNIP podem contribuir como moduladores genéticos no enrijecimento vascular / Introduction: Arterial stiffness is a complex phenomenon characterized by decreased vascular compliance during physiological and pathological stimuli. Similar to other cardiovascular phenotypes, arterial stiffness etiology is modulated by environmental and genetic factors. Considering the moderate heritability and its polygenic phenotype, genetic markers investigations related to different systems involved in vascular remodeling are interesting. Objectives: To assess the impact of the p22phox C242T, TXNIP G1036C, APOE C609T/T471C, elastin G1355A, ACE I/D and MMP-9 A855G polymorphisms on arterial stiffness phenotype in a general population. Methods: This study included 1,663 individuals of the general population from Vitória-ES. DNA was extracted from a venous blood sample and genotyping assays were performed for the genetic variants described above. Arterial stiffness was evaluated by pulse wave velocity (PWV). Results: Regarding PWV, p22phox C242T and TXNIP G1036C polymorphisms were significantly associated. Individuals carrying TT genotype of the p22phox C242T (CC + CT vs TT = 9.8 m/s = 10.1 m/s, p = 0.02) and individuals carrying G allele of the TXNIP G1036C polymorphisms (CG + CC = 9.8 m/s vs GG = 10.0 m/s, p = 0.03) had higher PWV values. However, APOE C609T/T471C (2=10.0 m/s, 3=9.8 m/s, 4=9.8 m/s, p=0.60), elastin G1355A (AA=9.8 m/s, GA=9.9 m/s, GG=9.8 m/s, p=0.92), ACE I/D (DD=9.8 m/s, DI=9.8 m/s, II=9.9 m/s, p=0.53) and MMP-9 A855G (AA=9.8 m/s, GA=9.8 m/s, GG= 9.8 m/s, p=0.60) polymorphisms did not present association. Only the TT genotype of the p22phox C242T polymorphism (OR = 1.93, p = 0.002) presented an increased risk for the arterial stiffness phenotype. Already TXNIP G1036C (OR=1.19, p=0.19), APOE C609T/T471C (OR=1.14, p=0.33), elastin G1355A (OR=0.81, p=0.28), ACE I/D (OR=0.91, p=0.48) and MMP-9 A855G (OR=1.01, p=0.95) polymorphisms did not present risk. Conclusion: The p22phox C242T and the TXNIP G1036C polymorphisms may contribute to genetic modulators in vascular stiffening

There is growing evidence to suggest that vascular disease plays an important role in late life depressive disorder. The aim of this study was to characterize vascular impairment in late life depression. Assessment of endothelial function, arterial stiffness, and atherosclerosis in a variety of vessel beds was carried out in 25 subjects with late life depression and 21 nondepressed control subjects. All study subjects underwent wave velocity, pulse wave analysis, carotid intima media thickness analysis, and magnetic resonance imaging of the brain and a subset gluteal fat biopsy and direct assessment of small artery endothelial function. There were no baseline differences in demographics or a range of vascular risk factors between the groups. There was a generalised vascular dysfunction in depressed subjects with significantly more atherosclerosis, poorer endothelial function and increased arterial stiffness. On neuroimaging, depressed subjects had significantly more dilated Virchow-Robin spaces in the basal ganglia. White matter lesion volumes in all regions were higher in depressed subjects but not significantly so. Furthermore, subjects with late onset depression (onset >60years) had greater vascular impairment when compared to those with early onset illness. Lastly, depressed subjects who did not respond to antidepressant monotherapy showed more vascular dysfunction compared to responders. The study has a number of limitations including the small sample size and as the study was cross sectional, the observed relationship between vascular dysfunction and depression is associative rather than causal. Further research in larger samples is required to address the methodological limitations of this study. If the study results are confirmed, the use of vasoprotective drugs to improve vascular function or retard atherosclerosis as diasease modifying agents in late life depression would be a rational development.

Gallstones have been linked to dyslipidemia, metabolic syndrome and cardiovascular disease. Arterial stiffness is an indicator of subclinical atherosclerosis. The aim of this study was to prospectively examine the relationship between gallstone disease and arterial stiffness progression in 347 men and 454 women. These subjects were followed for 7 years. Arterial stiffness progression was measured based on increases in brachial-ankle pulse wave velocity. Changes in brachial-ankle pulse wave velocity during the study period were significantly greater in patients with gallstones than in subjects without gallstones. After adjusting for multiple risk factors, gallstone disease was found to be a significant and independent predictor of brachial-ankle pulse wave velocity progression (β=0.189; P<0.001). In conclusion, gallstone disease is an independent predictor of arterial stiffness progression, even after adjusting for other cardiovascular risk factors.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19362号 / 医博第4039号 / 新制||医||1011(附属図書館) / 32376 / 新制||医||1011 / 京都大学大学院医学研究科医学専攻 / (主査)教授 横出 正之, 教授 佐藤 俊哉, 教授 森田 智視 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

No description available.

Cerebral palsy (CP) is a disability that impacts a person throughout their lifespan and may place adults with the condition at an increased risk of physical inactivity and cardiovascular disease. Cardiovascular structure and function in adults with CP has not been comprehensively investigated previously. In the current cross-sectional, observational study, endothelial function, carotid distensibility, and arterial stiffness were assessed using flow-mediated dilation (FMD), B-mode ultrasound, and pulse wave velocity (PWV), respectively, in forty adults with CP (age 33.7 ± 12.7 years). The study sample was separated based on whether subjects were community ambulant or community non-ambulant using the Gross Motor Function Classification System (GMFCS). Those in GMFCS I-II were labeled community ambulant (age 31.7 ± 10.4 years) while those in GMFCS III-V were community non-ambulant (age 34.8 ± 13.6 years). Resting arterial stiffness was examined through assessment of central and upper and lower limb peripheral PWV (cPWV, uPWV, lPWV). Carotid intima-media thickness (IMT), a measure of vascular structure, was also quantified using B-mode ultrasound images and a semi-automated edge detection software program. cPWV was calculated using the distance (carotid to femoral using the subtraction method) and time delay between the foot of the carotid waveform and the foot of the femoral waveform. uPWV was calculated from the carotid to radial artery distance (subtracting the distance from the carotid to sternal notch from the carotid to radial distance) and the time delay between the arrival of the foot of each corresponding waveform. lPWV was calculated from the femoral to posterior tibialis artery using the distance between each site and time delay between the arrival of the foot of each corresponding waveform. Physical activity (PA) levels were assessed using Actigraph accelerometry with cut points that had been previously determined in normal adults. Cardiometabolic markers of fasting serum interleukin-6, insulin, glucose, and a lipid panel were analyzed. The non-ambulant group had an increased uPWV (10.2 m/s ± 1.9) compared to the ambulant group (8.28 m/s ± 1.6) (p<0.01) despite no differences in cPWV or lPWV. There were no group differences (p>0.05) in absolute, relative or normalized FMD responses. Both groups also had similar values of carotid IMT and carotid distensibility. No group differences were found in any of the cardiometabolic or inflammatory markers. Moderate-to-vigorous PA (MVPA) levels were greater in the ambulant group (2.4 mins ± 2.1 per hour) compared to the non-ambulant group (0.3 mins ± 0.6 per hour) (p<0.01). Furthermore, sedentary time was greater in the non-ambulant group (57.8 mins ± 1.9 per hour) compared to the ambulant group (51.6 mins ± 4.7 per hour) (p<0.01). Despite differences in PA levels, MVPA was not a significant independent predictor of vascular or metabolic health in this cohort of adults with CP. However, GMFCS level was predictive of both uPWV and resting heart rate. Future research should include adults with CP who are older in age to gain further insight into the potential consequences of an activity-limited lifestyle (specifically in the non-ambulant group) on cardiovascular and metabolic health in this clinical population. / Thesis / Master of Science in Kinesiology

No description available.

No description available.