Medizinische Universität Graz Austria/Österreich - Forschungsportal - Medical University of Graz
Gewählte Publikation:
Sen, A.
Influence of Lifestyle factors on Leukocyte Telomere Length and Brain Aging.
PhD-Studium (Doctor of Philosophy); Humanmedizin; [ Dissertation ] Medical University of Graz; 2014. pp. 66
- Autor*innen der Med Uni Graz:
- Sen Abhijit
- Betreuer*innen:
- Schmidt Helena
- Schmidt Reinhold
- Altmetrics:
- Abstract:
- My thesis aim to study the influence of lifestyle factors on leukocyte telomere length (LTL) and Brain Aging. All the studies (cross-sectional study)were performed in the healthy elderly individuals¿(age ranging from 45 to 86 years) in the settings of Austrian Stroke Prevention Study(ASPS). My thesis is divided into three projects. In the first project, we assessed the effects of plasma concentrations of anti-oxidative micro-nutrients on LTL in 786 individuals with mean age of 66(±7) years and 58% women. We measured concentrations of vitamin C, lutein+zeaxanthin, ß-Cryptoxanthin, canthaxanthin, lycopene, ¿- and ¿-tocopherol, ¿- and ß-carotene and retinol in plasma, advanced oxidation protein products as a measure of oxidative stress in serum as well as leukocyte telomere length. Vitamins and carotenoids were measured by HPLC, advanced oxidation protein products(AOPP) by spectrophotometry and telomere length by quantitative real-time PCR. We speculated that the higher concentration of lutein+zeaxanthin and vitamin C were associated with longer telomere length. The associations were independent of lifestyle factors, vascular risk factors and were not mediated by AOPP content. In the second project, we investigated the cross-sectional relationship between maximal oxygen consumption (VO2max), white matter lesion (WML)volume and brain parenchymal fraction(BPF).The study consist of 715 individuals who underwent brain MRI with semi-automated measurement of WML volume (cm3),silent cerebral infarcts (SCI) and automated assessment of BPF (%) by the use of SIENAX. A maximal exercise stress test was done on a bicycle Ergometer. We observed that the protective effect of CRF on white matter lesion load in men but not in women. In the third project, the objective of our study was to examine the cross-sectional association between plasma concentrations of anti-oxidative micro-nutrients and global (g-factor) as well as domain-specific cognitive function in 767 healthy elderly individuals with mean age of 66(±7)years and 58% women. We further assessed whether the relationship between micro-nutrients and cognitive function is mediated by age-related cerebral MR changes including brain atrophy and WML volume. We measured plasma concentrations of vitamin C, lutein+zeaxanthin, ß-Cryptoxanthin, canthaxanthin, lycopene, ¿- and ¿-tocopherol, ¿- and ß-carotene and retinol by HPLC. Cognitive function measurements included composite scores of memory, executive function, visuopractical skills, attention-speed and g-factor. All subjects underwent brain MRI with automated assessment of brain parenchymal fraction (BPF,%) and semi-automated measurement of WML volume (cm3). After performing linear regression analysis, we observed that higher provitaminA and non-provitaminA concentrations were associated with `visuopractical skills¿ and `executive function¿,respectively. The associations were independent of vascular risk factors and were not mediated by BPF and WML volume.