Medical Sciences Commons^™

An Ewas Of Dementia Biomarkers And Their Associations With Age, African Ancestry, And Ptsd, Mark W. Miller, Erika J. Wolf, Xiang Zhao, Mark W. Logue, Sage E. Hawn

Psychology Faculty Publications

Background

Large-scale cohort and epidemiological studies suggest that PTSD confers risk for dementia in later life but the biological mechanisms underlying this association remain unknown. This study examined this question by assessing the influences of PTSD, APOE ε4 genotypes, DNA methylation, and other variables on the age- and dementia-associated biomarkers Aβ40, Aβ42, GFAP, NfL, and pTau-181 measured in plasma. Our primary hypothesis was that PTSD would be associated with elevated levels of these markers.

Methods

Analyses were based on data from a PTSD-enriched cohort of 849 individuals. We began by performing factor analyses of the biomarkers, the results of which …

Epigenetic Pathogenesis Of Neurological Disorders In Utero And Considerations For Genetic Counseling, Lauren Juga

Senior Honors Theses

Epigenetic modifications are a major focus of study in the pathogenesis of many disorders regarding metabolism, aging, neurodevelopment, and neurodegeneration. Epigenetic mechanisms are present throughout life but are especially vital to guiding fetal development. The precise timing of gene activation and deactivation guides stem cell differentiation through each embryonic stage. After exposure to environmental stimuli, gene expression can be altered by transcription factors, resulting in observable phenotypes and even pathology. Here, the epigenetic mechanisms responsible for the pathogenesis of neurodevelopmental and neuropsychiatric disorders are explored in response to environmental perturbations in utero. The present goal is to identify correlations between …

The Role Of Ms-818 In Altering Age-Related Characteristics Of An In Vitro Model Of Senescence In Neural Stem Cells, Sandeep Sreerama

Honors Undergraduate Theses

Aging of the brain is the leading risk factor for neurodegenerative diseases and brain cancers and has deleterious effects on brain functions. It follows that attempts to reverse the aging process may be therapeutically valuable. Neural stem cells (NSC) have been shown to play a critical role in maintaining brain functions, and their number is severely decreased with age. The development of senescence-like characteristics and declining functions in NSCs have been proposed to be responsible for brain aging and tumorigenesis. MS-818 is a pyrrolopyrimidine that has been shown to increase the NSC population and reverse the decline of behavioral function …

Uniaxial Stretch-Induced Regulation Of Mitogen-Activated Protein Kinase, Akt And P70s6 Kinase In The Ageing Fischer 344 × Brown Norway Rat Aorta, Kevin M. Rice, Devashish H. Desai, Deborah L. Preston, Paulette S. Wehner, Eric R. Blough

Deborah L Preston

The effects of ageing on the cardiovascular system contribute to substantial alterations in cellular morphology and function. The variables regulating these changes are unknown; however, one set of signalling molecules that may be of particular importance in mediating numerous cellular responses, including control of cell growth, differentiation and adaptation, are the proteins associated with the mitogen-activated protein kinase (MAPK) signalling systems. The MAPKs, in conjunction with the p70 S6k signalling cascade, have emerged as critical components for regulating numerous mechanotransduction-related cellular responses. Here we investigate the ability of uniaxial stretch to activate the MAPK and p70 S6k pathways in adult …

Discovery Of Molecular Associations Among Aging, Stem Cells, And Cancer Based On Gene Expression Profiling., Xiaosheng Wang

Journal Articles: Genetics, Cell Biology & Anatomy

The emergence of a huge volume of "omics" data enables a computational approach to the investigation of the biology of cancer. The cancer informatics approach is a useful supplement to the traditional experimental approach. I reviewed several reports that used a bioinformatics approach to analyze the associations among aging, stem cells, and cancer by microarray gene expression profiling. The high expression of aging- or human embryonic stem cell-related molecules in cancer suggests that certain important mechanisms are commonly underlying aging, stem cells, and cancer. These mechanisms are involved in cell cycle regulation, metabolic process, DNA damage response, apoptosis, p53 signaling …

Neuroangiogenesis: A Vascular Basis For Alzheimer's Disease And Cognitive Decline During Aging, Charles T. Ambrose

Microbiology, Immunology, and Molecular Genetics Faculty Publications

Angiogenesis directs development of the brain's microcirculation during antenatal and postnatal development, but its role later in life is less well recognized. I contend that during senescence a reduced cerebral capillary density accounts in part for the vascular cognitive impairment observed in many older persons and possibly for some forms of Alzheimer's disease. I propose that neuroangiogenesis is essential throughout adult life for maintaining the microcirculation of the cerebral cortex and elsewhere in the brain and that it commonly declines with old age. To support this hypothesis I have examined the neurological literature for relevant studies on cerebral capillary density …

The Effects Of Age And Heterochromatin On Frequencies Of Acquired Chromosomal Aneuploidy In Uncultured Human Leukocytes, Noran Aboalela

Theses and Dissertations

While age-related sex chromosomal aneuploidy is a well-characterized phenomenon, the relationship between autosomal loss and age remains unclear. The emergence of the specific and highly sensitive fluorescence in situ hybridization (FISH) technology has enabled investigators to study interphase cells, thereby overcoming problems inherent with the study of metaphase spreads for acquired aneuploidy assessment. Despite all the advantages of this technique, there are some limitations that could be misleading when scoring interphase autosomal aneuploidy. In this study we show that sex chromosomal hypoploidy is correlated with age. By using a twin study design, we evaluated Y chromosome hypoploidy frequencies and found …

Mechanisms Associated With Aging And Age-Related Disease In Drosophila, Melanie Jones

Theses and Dissertations

Aging is an intrinsic process that is independent of obvious disease. In contrast to normal aging, age-related diseases are conditions that typically manifest at advanced ages, are associated with explicit pathology and cause disability and premature death. We used Drosophila as a model to investigate the molecular-genetic mechanisms associated with aging and age-related disease. Age-related locomotor impairment (ARLI) is a serious condition for the elderly and greatly impacts their quality of life. Toward identifying genes and mechanisms that influence ARLI, we performed a forward genetic screen using Drosophila mutants. This screen identified a loss of function mutant in PDK1, a …

Effects Of Altered Superoxide Dismutase Expression On Age-Related Functional Declines And Survival In Drosophila, Ian Martin

Theses and Dissertations

Most organisms experience progressive declines in physiological function as they age. A number of studies in a variety of species support a strong link between oxidative damage, age-related functional declines and life span determination. Here, manipulating the expression levels of superoxide dismutase (SOD) isoenzymes SOD1 and SOD2, resulted in altered functional senescence and survival characteristics in Drosophila. Overexpression of cytosolic Sod1 using the yeast GAL4/UAS system conferred a 30-34% increase in mean life span and resulted in an attenuated senescence of odor avoidance behavior in aging flies. Tissue-specific Sod1 overexpression selectively in the nervous system or muscle failed to reproduce …

A Critical Review Of Telomerase Biology And Model Systems For The Study Of Telomerase, Jeremy Charles Aisenberg

Theses and Dissertations

The study of telomere and telomerase biology holds substantial promise in uncovering the molecular process of aging and the treatment of cancers. Studies have shown that telomere shortening is directly linked to cellular aging and that telomerase expression is found in over 85% of human cancers, including 95% of all advanced malignancies. Development of effective model systems to elucidate the molecular mechanisms underlying the role of telomeres and telomerase in the processes aging and cancer is of particular importance. While inbred strains of mice have provided a wealth of information for a variety of pathways and diseases, the mouse model …

A Drosophila Deg/Enac Channel Subunit Is Required For Male Response To Female Pheromones, Heping Lin, Kevin J. Mann, Elena Starostina, Ronald D. Kinser, Claudio W. Pikielny

Dartmouth Scholarship

Odorants and pheromones as well as sweet- and bitter-tasting small molecules are perceived through activation of G protein-coupled chemosensory receptors. In contrast, gustatory detection of salty and sour tastes may involve direct gating of sodium channels of the DEG/ENaC family by sodium and hydrogen ions, respectively. We have found that ppk25, a Drosophila melanogaster gene encoding a DEG/ENaC channel subunit, is expressed at highest levels in the male appendages responsible for gustatory and olfactory detection of female pheromones: the legs, wings, and antennae. Mutations in the ppk25 gene reduce or even abolish male courtship response to females in the dark, …