Exercise-induced telomerase gene expression is dependent on age and gender

Cluckey, Travis (2017) Exercise-induced telomerase gene expression is dependent on age and gender. Masters thesis, Northern Arizona University.

Text Cluckey_T_Exercise_induced_telomerase_gene_expression.pdf Restricted to Repository staff only Download (1MB) | Request a copy

Abstract

The ability to repair cellular damage is reduced with aging, resulting in increased cellular senescence. Telomeres, the protective caps of the chromosome, shorten as cells divide but the rate of telomere attrition is regulated by two proteins: telomerase and shelterin. An increase in telomerase activity could slow down the rate of telomere shortening, while shelterin prevents telomere elongation by blocking telomerase. Acute exercise stimulates telomerase in young men, as measured by increased expression of telomerase reverse transcriptase (hTERT). The aim of the present study was to investigate age-related differences in telomerase and shelterin response to exercise. We hypothesized that acute exercise would stimulate an increase in telomerase activity without an increase in activity of shelterin in both young and older individuals and that the hTERT response would be attenuated with aging. Young (22 ±2y, n=11) and older (60 ±2y, n=8) men and women performed a 30-minute high intensity interval cycling exercise and blood was collected before and at 30, 60, and 90 minutes after exercise. Gene expression of hTERT and TRF2 (telomere repeat binding factor 2, a shelterin protein) were measured in peripheral blood mononuclear cells (PBMCs) as markers of telomerase and shelterin activity, respectively. Additionally, gene expression of interleukin-6 (IL- 6) was measured as a positive control of the exercise stimulus. The trial induced a significant hTERT response in the cohort as a whole (p<0.05) with a greater increase in the young as compared to the older group (time-by-age group interaction p<0.05). As expected TRF2 did not change in response to the trial, however older individuals had significantly higher TRF2 response at +60 min (p<0.05). There was a significant time-by-age group interaction for IL-6 gene expression (p=0.048). These data support our hypothesis that telomerase gene expression attenuates with age in response to high intensity exercise. Unexpectedly, there was a gender difference where men had significantly greater hTERT (p<0.05) and TRF2 (p<0.05) responses compared to women, regardless of age. The role of gender was a novel finding and should be explored in future research.

Item Type:	Thesis (Masters)
Publisher’s Statement:	© Copyright is held by the author. Digital access to this material is made possible by the Cline Library, Northern Arizona University. Further transmission, reproduction or presentation of protected items is prohibited except with permission of the author.
Keywords:	cellular senescence; Age; Exercise; Gender; High intensity; Telomerase
Subjects:	Q Science > QH Natural history > QH301 Biology
NAU Depositing Author Academic Status:	Student
Department/Unit:	Graduate College > Theses and Dissertations College of Engineering, Forestry, and Natural Science > Biological Sciences
Date Deposited:	20 Dec 2017 21:38
URI:	http://openknowledge.nau.edu/id/eprint/4978

Actions (login required)

IR Staff Record View

Downloads