Vitamiin D ja angiotensiin II retseptori blokaatori mõju arterikahjustustele

Väitekirja elektrooniline versioon ei sisalda publikatsioone.Vitamiin D biofunktsioonidest on viimastel aastatel palju tähelepanu pööratud toimetele, mis pole otseselt seotud kaltsiumi ainevahetusega. Nii on leitud, et madal vitamiin D tase, mis on levinud kliiniline probleem Põhja-Euroopas, on seotud kõrgema südame- ja veresoonkonna haiguste riskiga. Suurte arterite (sh. aordi) seinte jäigenemine on organismi vananemise ja südame- ja veresoonkonna haigustega kaasnev protsess, mille aluseks on arterite struktuursed-funktsionaalsed muutused. Diabeedi korral on oluliselt tõusnud risk arterite kahjustuste tekkeks, mille varane tuvastamine ja leevendamine on diabeedi konventsionaalses ravis määrava tähtsusega. Püsivalt kõrge veresuhkru tase soodustab kudedes, sealhulgas arterite seintes, valkude pöördumatut glükeerimist. See halvendab põhiliste struktuursete valkude, kollageeni ja elastiini, biomehaanilisi omadusi ja tõstab arterite jäikust. Valkude glükeerimist süvendab tugev kestev oksüdatiivne stress. Diabeediga kaasneb ka liigne reniin-angiotensiin süsteemi aktivatsioon, mis tõstab arteriaalset vererõhku ning pikas perspektiivis süvendab arterite remodelleerumist ja jäigenemist. Me leidsime, et eksperimentaalses diabeedimudelis oli arterikahjustuste varajasteks tunnusteks suurenenud aordi jäikus ning halvenenud elastsete kiudude struktuurne terviklikkus. Aordiseinas olid kuhjunud glükeerimise lõpp-produktid, millega kaasnes oluline oksüdatiivse stressi taseme tõus ning süsteemse antioksüdantse vastuse nõrgenemine. Vitamiin D lisamanustamisel paranesid aordiseina struktuursed kahjustused, vähenes koevalkude glükeerimine ja oksüdatiivse stressi tase ning paranes antioksüdantne vastus. Samal määral vähendas diabeedimudelis aordiseina struktuurseid muutuseid angiotensiin II retseptori blokaatori telmisartaani manustamine, mis lisaks langetas aordi jäikust.In recent years, increased attention has been paid to vitamin D biofunctions not inherently associated with calcium metabolism. As a result, it has been found that low vitamin D levels, a common clinical problem in Northern Europe, are associated with increased risk of cardiovascular disease. Stiffening of large arteries (including the aorta) is a manifestation of structural and functional changes within the arterial wall that occur with increasing age and cardiovascular disease. Diabetes mellitus significantly increases the risk of arterial damage which highlights the importance of early detection and treatment of diabetic vascular complications. Sustained high blood glucose levels induce irreversible glycation of proteins within tissues including the arterial wall. This impairs the biomechanical properties of the main structural proteins, collagen and elastin, and increases arterial stiffness. Glycation of proteins is exacerbated by persistent high-grade oxidative stress. Diabetes is also associated with excessive activation of the renin-angiotensin system which increases arterial blood pressure and induces arterial remodelling and stiffening in the long term. We found that the early signs of arterial damage in experimental diabetes are increased aortic stiffness and disturbed integrity of elastic fibres within the aortic wall. Diabetes was also characterised by profound accumulation of advanced glycation end-products in the aortic wall, increased oxidative stress level and decreased systemic antioxidant capacity. Administration of vitamin D improved the structural damages within the aortic wall, reduced the glycation of tissue proteins and oxidative stress level, and increased systemic antioxidant capacity. Treatment with an angiotensin II receptor blocker telmisartan similarly improved the structural integrity of the aortic wall and also reduced aortic stiffness

Relations between vitamin D status, muscle tone and body composition in soldiers: association with long-term mission

Vitamin D level is known to play an important role in the regulation of different human functions, including the functions of the cardio-vascular and musculoskeletal systems. The aim of the study was to find relations between vitamin D level, skeletal muscles tone and body composition in conditions of prolonged physical load.Sixty-five well-trained male soldiers from the Estonian ESTCOY-8 infantry company were examined before and after a six-month military mission to assess the soldiers’ vitamin D level, skeletal muscles tone and body composition.The results of the study showed that, during the long-term military mission, muscle tone of lower extremities decreased in conditions where vitamin D status was significantly increased (from average 40 to 104 nmol/L; p<0.001). We also found that the upper and middle part m. trapezius tone increased significantly during long-term strenuous military mission.Our study showed that the long-time military mission influenced the skeletal muscles functional state. Decrease in muscle tone of lower extremities was related to increase in serum vitamin 25(OH)D level (in average by 64nmol/L). At the same time muscle tone of m. trapezius increased in our group of subjects, and this increase was linked to WHR

Relationship between soldiers' body height-weight category and changes in their spinal column kyphotic curvature during a long-term military mission

Prolonged physical load can unfavourably influence the human vertebral column. Thirty-six well-trained male soldiers from the Estonian ESTCOY-8 infantry company were examined before and after a 6-month military mission to assess the effect of long-term physical load on soldiers’ spinal column kyphotic curvature in relation to their body build (height-weight category). Body height and weight of the men under study were measured before and after the 6-month-long military mission. BMI was calculated as the body weight (kg) divided by the square of the standing body height (m). Body height-weight category was assessed according to Kaarma et al. 2008. Spine kyphotic curvature in the sagittal plane was recorded using pantography. The results of the study showed that significant kyphotic curvature appeared in half of the well-trained soldiers. Changes in kyphotic curvature were related to the person’s body build (height-weight category). Subjects with a larger body seemed to have greater stability of kyphotic curvature

Estimation of specific VO2max for elderly in cycle ergometer

The aim of the present study was to develop and validate a specific estimation model of maximal oxygen consumption (VO2max) based on submaximal ventilatory indicators on a cycle ergometer test protocol in elderly men. We tested, using an incremental protocol, 181 healthy and non-athletes male volunteers, aged between 60 and 79 years old, randomly divided into two groups: group A, of estimation (n = 137), and group B, of validation (n = 44). The independent variables were: body mass in kg, second workload threshold (WT2) and heart rate at the second ventilatory threshold (VT2). The cross-validation method was used in group B, with group A serving as the basis for the model and the validation dataset. The results presented a multiple linear regression model for estimation of VO2max = 31.62 + 0.182 (WT2) – 0.302 (body mass) in mlO2/kg/min-1; adjusted R2 = 0.98 and SEE = 0.682 (mlO2/Kg/min-1). The construction of this specific model for healthy and non-athletes elderly men can demonstrate that it is possible to estimate VO2max with a minimum error (SEE < 1.00) from indicators of ventilatory thresholds obtained in an incremental submaximal test

Curso de Aperfeiçoamento Moodle: Abertura

Para reproduzir os arquivos de áudio do Acervo Digital da Unesp recomenda-se o programa reprodutor de mídia digital Windows Media Player ou similar. O navegador Mozilla Firefox atualizado reproduz com excelência áudios em MP3.Audio da apresentação do Curso de Aperfeiçoamento Moodle oferecido pelo NEaD/Unesp e a PROEx (Pró-Reitoria de Extensão Universitária) realizada pelo professor Klaus Schlünzen Junior, um dos autores do curso. No vídeo é apresentado panorama do do curso, suas ferramentas, atividades e objetivos

Angiotensin II receptor blocker telmisartan attenuates aortic stiffening and remodelling in STZ-diabetic rats

Background: Prevention or attenuation of diabetic vascular complications includes anti-hypertensive treatment with renin-angiotensin system inhibitors on account of their protective effects beyond blood pressure reduction. The present study aimed to investigate the effects of telmisartan, an angiotensin II type 1 receptor blocker (ARB), on blood pressure, aortic stiffening, and aortic remodelling in experimental type 1 diabetes in rats. Methods. Diabetes was induced by streptozotocin (STZ) (65 mg/kg) in male Wistar rats. One diabetic group was treated for 10 weeks with telmisartan (10 mg/kg/day p/o). Pressure-independent aortic pulse wave velocity (PWV) was measured under anaesthesia after intravenous infusion of phenylephrine and nitroglycerine. Aortic wall samples were collected for histomorphometrical analysis. Results: Untreated diabetes imposed differential effects on aortic stiffening, as demonstrated by increased isobaric PWV over a range of high blood pressures, but not at lower blood pressures. This was associated with loss and disruption of elastin fibres and an increase in collagen fibres in the aortic media. Treatment with telmisartan decreased resting blood pressure, reduced aortic stiffness, and partially prevented the degradation of elastin network within the aortic wall. Conclusions: Telmisartan improved the structural and functional indices of aortic stiffening induced by untreated STZ-diabetes, demonstrating the importance of ARBs in the therapeutic approach to diabetic vascular complications.10 page(s

Aplicabilidad de los modelos de periodización del entrenamiento deportivo. Una revision sistemática

With the development of training, the way in which the coaches structure the workloads was adapted to their needs. The objective of this study was to identify the model that allows greater efficiency and Applicability, based on an analysis of 12.342 references to publications from 2004 and 2005 found in databases, and updated in late 2008. The selected sample, after exclusion criteria, consisted of 103 publications. The methodology used was the systematic review and Size-Effect inferential statistical method, enabling the establishment of an Index of Applicability (IAPLIC). The models of periodization Classical, ATR and Structural Bells showed a �Very Good� IAPLIC and the models Prioritized and in Blocks, a "Good� one. It is concluded that the models with "Very Good" IAPLIC are the ones with the best applicability.Con la evolución del entrenamiento la forma en la cual los técnicos estructuran las cargas de trabajo se ha ido adaptando a sus propias necesidades. El objetivo de este estudio ha sido identificar el modelo que permita una mayor eficacia y aplicabilidad, partiendo del análisis de 12.342 referencias bibliográficas correspondiente a publicaciones realizadas entre los años 2004 y 2005, que podemos encontrar en bases de datos, y actualizados al final de 2008. La muestra seleccionada, tras aplicar criterios de exclusión, configuró 103 publicaciones. La metodología utilizada fue la revisión sistemática y el método estadístico inferencial de Tamaño-Efecto, posibilitando el establecimiento de un Índice de Aplicabilidad (IAPLIC). Los modelos de periodización Clásica, ATR y Campanas Estructurales presentaron un IAPLIC �Muy Bueno�, y los modelos Prioritario y en Bloques, �Bueno�. Se concluye que estos modelos con un IAPLIC �Muy Bueno� son los de mejor aplicabilidad

Effect of vitamin D on aortic remodeling in streptozotocin-induced diabetes

Background: Diabetes mellitus is associated with micro-and macrovascular complications and increased cardiovascular risk. Elevated levels of serum asymmetric dimethylarginine (ADMA) may be responsible for endothelial dysfunction associated with diabetes-induced vascular impairment. Vitamin D may have potential protective effects against arterial stiffening. This study aimed to examine both the effects of diabetes on the functional/structural properties of the aorta and the endothelial function and the effects of vitamin D supplementation. Methods: Male Wistar rats (n = 30) were randomly assigned to control untreated, diabetic untreated, and diabetic + cholecalciferol groups. Diabetes was induced by intraperitoneal injection of streptozotocin, followed by oral administration of cholecalciferol (500 IU/kg) for 10 weeks in the treatment group. Aortic pulse wave velocity (PWV) was recorded over a mean arterial pressure (MAP) range of 50 to 200 mmHg using a dual pressure sensor catheter. Intravenous infusion of phenylephrine and nitroglycerine was used to increase and decrease MAP, respectively. Serum 25-hydroxyvitamin D [25(OH) D] levels were measured using a radioimmune assay. ADMA levels in serum were measured by enzyme-linked immunoassay. Aortic samples were collected for histomorphometrical analysis. Results: PWV up to MAP 170 mmHg did not reveal any significant differences between all groups, but in diabetic rats, PWV was significantly elevated across MAP range between 170 and 200 mmHg. Isobaric PWV was similar between the treated and untreated diabetic groups, despite significant differences in the levels of serum 25(OH) D (493 +/- 125 nmol/L vs 108 +/- 38 nmol/L, respectively). Serum levels of ADMA were similarly increased in the treated and untreated diabetic groups, compared to the control group. The concentration and integrity of the elastic lamellae in the medial layer of the aorta was impaired in untreated diabetic rats and improved by vitamin D supplementation. Conclusion: PWV profile determined under isobaric conditions demonstrated differential effects of uncontrolled diabetes on aortic stiffness. Diabetes was also associated with elevated serum levels of ADMA. Vitamin D supplementation did not improve the functional indices of aortic stiffness or endothelial function, but prevented the fragmentation of elastic fibers in the aortic media.8 page(s

Effect of vitamin D on aortic remodeling in streptozotocin-induced diabetes

Abstract Background Diabetes mellitus is associated with micro- and macrovascular complications and increased cardiovascular risk. Elevated levels of serum asymmetric dimethylarginine (ADMA) may be responsible for endothelial dysfunction associated with diabetes-induced vascular impairment. Vitamin D may have potential protective effects against arterial stiffening. This study aimed to examine both the effects of diabetes on the functional/structural properties of the aorta and the endothelial function and the effects of vitamin D supplementation. Methods Male Wistar rats (n = 30) were randomly assigned to control untreated, diabetic untreated, and diabetic + cholecalciferol groups. Diabetes was induced by intraperitoneal injection of streptozotocin, followed by oral administration of cholecalciferol (500 IU/kg) for 10 weeks in the treatment group. Aortic pulse wave velocity (PWV) was recorded over a mean arterial pressure (MAP) range of 50 to 200 mmHg using a dual pressure sensor catheter. Intravenous infusion of phenylephrine and nitroglycerine was used to increase and decrease MAP, respectively. Serum 25-hydroxyvitamin D [25(OH)D] levels were measured using a radioimmune assay. ADMA levels in serum were measured by enzyme-linked immunoassay. Aortic samples were collected for histomorphometrical analysis. Results PWV up to MAP 170 mmHg did not reveal any significant differences between all groups, but in diabetic rats, PWV was significantly elevated across MAP range between 170 and 200 mmHg. Isobaric PWV was similar between the treated and untreated diabetic groups, despite significant differences in the levels of serum 25(OH)D (493 ± 125 nmol/L vs 108 ± 38 nmol/L, respectively). Serum levels of ADMA were similarly increased in the treated and untreated diabetic groups, compared to the control group. The concentration and integrity of the elastic lamellae in the medial layer of the aorta was impaired in untreated diabetic rats and improved by vitamin D supplementation. Conclusion PWV profile determined under isobaric conditions demonstrated differential effects of uncontrolled diabetes on aortic stiffness. Diabetes was also associated with elevated serum levels of ADMA. Vitamin D supplementation did not improve the functional indices of aortic stiffness or endothelial function, but prevented the fragmentation of elastic fibers in the aortic media.</p