Physiology Commons^™

Effects Of Life-Long Wheel Running Behavior On Plantar Flexor Contractile Properties, Alexander Nicholas Beechko

Electronic Theses, Projects, and Dissertations

Aging in skeletal muscle is characterized by a loss in muscular performance. This is in part related to the direct loss of muscle mass due to senescence, known as sarcopenia. With age, skeletal muscles lose force production, contractile speed, and power production. The force velocity relationship of muscle is a product of force production and contraction speed, both of which decline with age; however, the mechanisms and trajectory of this decline are not well understood. Exercise has positive effects on muscle, and thus may assist in maintaining performance in old age. However, few long-term studies have been performed to examine …

Similar Effects Of 24 Weeks Of Resistance Training Performed With Different Frequencies On Muscle Strength, Muscle Mass, And Muscle Quality In Older Women, Fábio Luiz Cheche Pina, João Pedro Nunes, Matheus Amarante Nascimento, Alex Silva Ribeiro, Jerry L. Mayhew, Edilson Serpeloni Cyrino

International Journal of Exercise Science

International Journal of Exercise Science 12(6): 623-635, 2019. The purpose of this study was to analyze the effects of 24 weeks of resistance training (RT) performed 2 vs. 3 times per week on muscle strength, muscle mass, and muscle quality in older women. Thirty-nine older women (≥ 60 years old) were randomly assigned to two groups according to RT frequency (G2x = two sessions per week, n=19; and G3x = three sessions per week, n=20) and were submitted to 24 weeks of whole-body RT, divided into two stages of 12 weeks. In the first stage, participants performed 1 set of …

The Role Of Sirt1 In Skeletal Muscle Function And Repair Of Older Mice, Matthew John Myers

Graduate Theses, Dissertations, and Problem Reports (ETD)

Human skeletal muscle is a highly metabolic tissue necessary for mobility and coordination. Responsible for approximately one-fifth of the resting human metabolism, skeletal muscle is also an important regulator of metabolites like glucose and contributes to the regulation of body temperature. Although there is a gradual decline in muscle mass associated with aging, a certain percentage of the population suffer from severe muscle mass and strength deterioration, classified as sarcopenia (5-13% for people aged 60-70 years old, 11-50% for those 80 or older). Sarcopenia is linked to increased morbidity and mortality rates in the elderly population, while annual healthcare costs …

Overexpression Of Cyb5r3 And Nqo1, Two Nad+-Producing Enzymes, Mimics Aspects Of Caloric Restriction, Alberto Diaz-Ruiz, Michael Lanasa, Joseph Garcia, Hector Mora, Frances Fan, Alejandro Martin-Montalvo, Andrea Di Francesco, Miguel Calvo-Rubio, Andrea Salvador-Pascual, Miguel A. Aon, Kenneth W. Fishbein, Kevin J. Pearson, Jose Manuel Villalba, Placido Navas, Michel Bernier, Rafael De Cabo

Pharmacology and Nutritional Sciences Faculty Publications

Calorie restriction (CR) is one of the most robust means to improve health and survival in model organisms. CR imposes a metabolic program that leads to increased stress resistance and delayed onset of chronic diseases, including cancer. In rodents, CR induces the upregulation of two NADH‐dehydrogenases, namely NAD(P)H:quinone oxidoreductase 1 (Nqo1) and cytochrome b₅ reductase 3 (Cyb5r3), which provide electrons for energy metabolism. It has been proposed that this upregulation may be responsible for some of the beneficial effects of CR, and defects in their activity are linked to aging and several age‐associated diseases. However, …

Body Composition, Muscular Performance, And Free Testosterone Following 12-Weeks Of Protein Supplementation And Resistance Training In Men Aged 35-55, Matthew Steven Stone

Graduate Theses and Dissertations

PURPOSE: The purpose of this study was to investigate the effects of 12 weeks of protein supplementation and Autoregulatory Progressive Resistance Exercise (APRE) training on measures of body composition, muscular performance, and free testosterone in middle-aged men. METHODS: Untrained males (n = 35; 43.3 ± 6.6 years) participated in this study. Lean mass (LM) and fat mass (FM) were measured via Dual Energy X-ray Absorptiometry (DEXA), while strength was measured utilizing one repetition maximum (1RM), endurance measured using maximum repetitions completed (REPS) at 75% 1RM for the bench and leg press, and free testosterone was measured using changes in serum …

Relative Handgrip Strength As A Simple Tool To Evaluate Impaired Heart Rate Recovery And A Low Chronotropic Index In Obese Older Women, Cristiane Rocha Da Silva, Dahan Da Cunha Nascimento, Ivo Sousa Neto, Ramires Tibana, Samuel Oliveira, Renato Valduga, Nayara Santos, Bruno Saraiva, Jonato Prestes, Jeffrey Willardson, Guilherme Borges Pereira

International Journal of Exercise Science

International Journal of Exercise Science 11(2): 844-855, 2018. The aim of the present study was to compare differences in heart rate response following a treadmill exercise test in elderly obese women categorized into groups based on relative handgrip strength. Eighty-eight obese elderly women who were between the ages of 60 and 87 participated in the study and were categorized and enrolled to one of two groups based on lower (< 1.51 m²) or higher (≥ 1.51 m²) relative handgrip strength, respectively. The heart rate recovery in the first and second minutes following the treadmill exercise test and the chronotropic index were compared between groups. The higher relative handgrip strength group presented a significantly higher peak heart rate during exercise and a quicker heart rate recovery following exercise versus the lower relative handgrip strength group (pp=0.059) toward a significantly greater chronotropic index in the higher versus the lower relative handgrip strength group. In conclusion, elderly women with greater relative handgrip strength also demonstrated a …

Serum Tumor Necrosis Factor-Alpha Associates With Myocardial Oxygen Demand And Exercise Tolerance In Postmenopausal Women, Stephen J. Carter, David R. Bryan, William H. Neumeier, Stephen P. Glasser, Gary R. Hunter

International Journal of Exercise Science

International Journal of Exercise Science 11(2): 42-54, 2018. The functional implications of serum tumor necrosis factor-alpha (TNF-a), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-a on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-a on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO_2max). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index …

Dysregulation Of Daf-16/Foxo3a-Mediated Stress Responses Accelerates T Oxidative Dna Damage Induced Aging, Aditi U. Gurkar, Andria R. Robinson, Yuxiang Cui, Xuesen Li, Shailaja K. Allani, Amanda Webster, Mariya Muravia, Mohammad Fallahi, Herbert Weissbach, Paul D. Robbins, Yinsheng Wang, Eric E. Kelley, Claudette M. St. Croix, Laura J. Niedernhofer, Matthew S. Gill

Faculty & Staff Scholarship

DNA damage is presumed to be one type of stochastic macromolecular damage that contributes to aging, yet little is known about the precise mechanism by which DNA damage drives aging. Here, we attempt to address this gap in knowledge using DNA repair-deficient C. elegans and mice. ERCC1-XPF is a nuclear endonuclease required for genomic stability and loss of ERCC1 in humans and mice accelerates the incidence of age-related pathologies. Like mice, ercc-1 worms are UV sensitive, shorter lived, display premature functional decline and they accumulate spontaneous oxidative DNA lesions (cyclopurines) more rapidly than wild-type worms. We found that ercc-1 worms …

Examining Effects Of Arousal And Valence Across The Adult Lifespan In An Emotional Stroop Task, Samantha E. Tuft

ETD Archive

As age increases, there is evidence that people tend to pay less attention to negative information, pay more attention to positive information, or both. There are many theoretical accounts that attempt to explain this positivity bias. In the current study, I examined positivity effects across the adult lifespan by evaluating competing predictions of two theories: Socioemotional Selectivity Theory, which is based in motivation, and Dynamic Integration Theory, which is based in capacity. Computer mouse tracking was used to examine effects across levels of Valence (negative, neutral, and positive) and Arousal (low, medium, and high) in an emotional Stroop task. Participants …

Micrornas, Heart Failure, And Aging: Potential Interactions With Skeletal Muscle, Kevin A. Murach, John J. Mccarthy

Center for Muscle Biology Faculty Publications

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression by targeting mRNAs for degradation or translational repression. MiRNAs can be expressed tissue specifically and are altered in response to various physiological conditions. It has recently been shown that miRNAs are released into the circulation, potentially for the purpose of communicating with distant tissues. This manuscript discusses miRNA alterations in cardiac muscle and the circulation during heart failure, a prevalent and costly public health issue. A potential mechanism for how skeletal muscle maladaptations during heart failure could be mediated by myocardium-derived miRNAs released to the circulation is presented. An overview …

Moderate-Load Muscular Endurance Strength Training Did Not Improve Peak Power Or Functional Capacity In Older Men And Women, Simon J. Walker, Greg G. Haff, Keijo K. Häkkinen, Robert U. Newton

Research outputs 2014 to 2021

The present study determined the effects of muscular endurance strength training on maximum strength and power, functional capacity, muscle activation and hypertrophy in older men and women. Eighty-one men and women acted as an intervention group while 22 acted as non-training controls (age range 64-75 y). Intervention training included super-sets (i.e., paired exercises, immediately performing the second exercises following completion of the first) with short rest intervals (30-60 s between sets) at an intensity of 50-60% one-repetition maximum (1-RM) for 15-20 repetitions. Concentric leg press actions measured maximum strength (1-RM) and concentric peak power. Functional capacity was assessed by maximum …

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Graduate Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study …

Development Of Activity In The Mouse Visual Cortex., Jing Shen, Matthew T Colonnese

Pharmacology and Physiology Faculty Publications

No abstract provided.

Power Training And Functional Performance In Middle Aged Women: A Pilot Study, Mitchel A. Magrini, J. Jay Dawes, Craig Elder, Mary Ann Kluge

International Journal of Exercise Science

International Journal of Exercise Science 9(3): 327-335, 2016. Muscular power is a key component of functional performance (FP) and fall risk reduction. The present study investigated the effect that power training with medicine balls had on body composition and FP in middle-age females. 10 women were divided into a control group (n=4, age=59.8+3.6) and an intervention group (n=6, age=59.5+3.6) in this 6-week study. The intervention group completed a medicine ball training program two times a week. Body composition and FP tests were administered prepost. Data was analyzed using a series of Wilcoxon Signed Ranks test and Cohen’s d test for …

Enhancement Of Aging Rat Laryngeal Muscles With Endogenous Growth Factor Treatment, Joseph C. Stemple, Richard D. Andreatta, Tanya S. Seward, Vrushali Angadi, Maria Dietrich, Colleen A. Mcmullen

Physical Therapy Faculty Publications

Clinical evidence suggests that laryngeal muscle dysfunction is associated with human aging. Studies in animal models have reported morphological changes consistent with denervation in laryngeal muscles with age. Life‐long laryngeal muscle activity relies on cytoskeletal integrity and nerve–muscle communication at the neuromuscular junction (NMJ). It is thought that neurotrophins enhance neuromuscular transmission by increasing neurotransmitter release. We hypothesized that treatment with neurotrophin 4 (NTF4) would modify the morphology and functional innervation of aging rat laryngeal muscles. Fifty‐six Fischer 344xBrown Norway rats (6‐ and 30‐mo age groups) were used to evaluate to determine if NTF4, given systemically (n = 32) …

Metabolic Therapy For Age-Dependent Impaired Wound Healing, Shannon Lynn Kesl

USF Tampa Graduate Theses and Dissertations

Chronic wounds represent an under-acknowledged socioeconomic epidemic, affecting 1.8 million new patients per year and costing the US health care system upwards of $25 billion annually. This substantial cost is rapidly growing due to a disproportionate occurrence in the ever-aging population. Key features associated with age-related impairment of wound healing include limited energy and nutrient exchange, unremitting inflammations, increased reactive oxygen species (ROS), and diminished blood flow. Most chronic wound therapies target specific molecular mechanisms; however, there are often multiple mitigating factors that prevent normal wound closure. This is likely one reason most wound therapies are minimally effective. In the …

The Role Of Subtelomeric Silencing In Aging, Mark Roth, Jonathan Alder, Phd

Journal of Undergraduate Research

Telomeres, located at the ends of chromosomes, are repetitive DNA sequences composed of TTAGGG repeated thousands of times. Each time a cell copies its DNA a small amount of telomeric DNA is lost due to the end replication problem. Because of this, telomeres are eventually lost. New telomeres are synthesized by telomerase. Telomerase has both a protein reverse transcriptase component (TERT) and an RNA template (TERC) that it uses to synthesize new telomeres; however, expression is tightly controlled and is not expressed in most cells in our bodies. This limits the number of times that most of our cells can …

Thrombospondin-1 Decreases No-Mediated Vasodilation In Coronary Arterioles In Advancing Age., Grant Mckenzie

College of Arts & Sciences Senior Theses

No abstract provided.

Tradeoffs Of Warm Adaptation In Aquatic Ectotherms: Live Fast, Die Young?, Eloy Martinez, Anthony Porreca, Robert Colombo, Michael Menze

Faculty Research & Creative Activity

In the face of a changing climate, questions regarding sub-lethal effects of elevated habitat temperature on the physiology of ectotherms remain unanswered. In particular, long-term responses of ectotherms to the warming trend in tropical regions are unknown, and understudied due to the difficulties in specimen and community traceability. In freshwater lakes employed as cooling reservoirs for power plants, increased physiological stress from high water temperature can potentially alter the community structure of fishes. We employ this highly tractable system to assess how thermal regimes can alter the physiology and ecology of aquatic species. We documented a significantly reduced lifespan, growth …

Mechanisms Of Estrogen Receptor Alternative Splicing And The Consequences For Aging In The Female Brain, Cody Lee Shults

Dissertations

The advances in healthcare and scientific knowledge have resulted in longer life expectancies in women. These advanced ages in women now means that they are experiencing the effects of age-related changes in the body for much longer periods of time, mainly reproductive senescence, resulting in the loss of circulating ovarian hormones. The age at which menopause occurs has not changed, resulting in women now living over a third of their lives in a postmenopausal state.

The major circulating estrogen produced by the ovaries, 17β-estradiol (E2), has many homeostatic effects in the body like neuroprotection and cardioprotection. Hormone replacement therapy (HT) …

Longitudinal Trajectories Of Cholesterol From Midlife Through Late Life According To Apolipoprotein E Allele Status, Brian Downer, Steven Estus, Yuriko Katsumata, David W. Fardo

Physiology Faculty Publications

Background: Previous research indicates that total cholesterol levels increase with age during young adulthood and middle age and decline with age later in life. This is attributed to changes in diet, body composition, medication use, physical activity, and hormone levels. In the current study we utilized data from the Framingham Heart Study Original Cohort to determine if variations in apolipoprotein E (APOE), a gene involved in regulating cholesterol homeostasis, influence trajectories of total cholesterol, HDL cholesterol, and total: HDL cholesterol ratio from midlife through late life.

Methods: Cholesterol trajectories from midlife through late life were modeled using generalized …

Understanding How Honey Bee Flight And Senescence Are Connected Through Oxidative Stress., Joseph Margotta

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this dissertation was to exploit the tractability of the honey bee (Apis mellifera) to understand how the physiological and cellular mechanisms that determine the onset and duration of senescence are shaped by behavioral development and behavioral intensity. These data reveal how behavior can damage cells and consequently limit lifespan. The honey bee represents the ideal model to address these factors because age, behavior, functional senescence, and lifespan are easily manipulated independently of each other while in its natural environment. I determined if there was a cause-effect relationship between honey bee flight and oxidative stress by comparing damage …

Development Of A Prediction Equation For Vertical Power In Masters Level Basketball Athletes, Jordan M. Glenn, Jennifer Vincenzo, Michelle Gray, Ashley Binns

International Journal of Exercise Science

International Journal of Exercise Science 7(2) : 119-127, 2014. Performance factors such as power, agility, and speed are important in sport-based competition for older individuals. Prediction models that assess these factors in masters level competitors are limited. The purpose of this study was to examine physical field measures of agility and speed and their ability to predict vertical power (VP) among basketball masters athletes(MA). Thirty-eight competitive MA from a Midwest Senior Olympic basketball tournament performed vertical jump, 20-yard dash (20-D), 40-yard dash (40-D), and T-test (TT) assessments. Regression analysis revealed a significant relationship (p = .002) using TT and …

The Effects Of Aging On Skeletal Muscle Ampk Activation And An Analysis Of Chronic Aicar Treatment On The Aging Phenotype, Shalene E. Hardman

Theses and Dissertations

AMP-activated protein kinase (AMPK), a metabolic regulator, acts in opposition to many of the effects of aging and may provide insights into the development of sarcopenia. However, the effect of aging on AMPK activation is unclear. The purpose of this dissertation was to: 1) clarify the controversy concerning the activation of AMPK in response to endurance-like exercise in aged skeletal muscle; 2) address mechanisms for the age-associated alterations in AMPK activation; and 3) address the known benefits of chronic AICAR treatment in aged skeletal muscle. First, to clarify the effect of age on AMPK activation, young adult (YA) (8 mo.) …

Validity Of Boston Marathon Qualifying Times, Paul M. Vanderburgh

Health and Sport Science Faculty Publications

Purpose: To assess the validity of Boston Marathon qualifying (BMQ) standards for men and women. Methods: Percent differences between BMQ and current world records (WR) by sex and age group were computed. WR was chosen as the criterion comparison because it is not confounded by intensity, body composition, lifestyle, or environmental factors. A consistent difference across age groups would indicate an appropriate slope of the age-vs-BMQ curve. Inconsistent differences were corrected by adjusting BMQ standards to achieve a uniform percentage difference from WR. Results: BMQ standards for men were consistently ~50% slower than WR (mean 51.5% ± …

Exercise Alters Glial Cell Line-Derived Neurotrophic Factor (Gdnf) Protein Content In The Spinal Cord, Monica Janine Mccullough

Dissertations

Neurotrophic factors may play a role in exercise-induced neuroprotective effects; however, it is not known if exercise mediates changes in glial cell line-derived neurotrophic factor (GDNF) protein levels in the spinal cord. The aim of the studies described herein was to determine if exercise alters GDNF protein expression in the lumbar spinal cord of healthy and diseased animals. The lumbar spinal cord was analyzed from adult rats aged 6-, 12-, 18- and 24-months, and from transgenic amyotrophic lateral sclerosis (ALS) mice and wild-type mice aged 3 months. Animals had undergone either forced wheel running, voluntary wheel running or swimming for …

The Role Of Macrophages In Exercise And Insulin Resistance In Human Skeletal Muscle, Jason S. Groshong

Theses and Dissertations--Physiology

Muscle biopsies were taken at baseline, post eccentric exercise, post aerobic training, and after training followed by eccentric exercise from adults with different health status. In Cell Western analysis of pAkt/Akt ratio suggests that muscle cells isolated from baseline biopsies respond to insulin in a dose dependent manner that tracks with sensitivity to insulin of the host; however, this is uncoupled from glucose disposal in vitro. Nitrotyrosine (NY), a marker of free radical damage, was employed to assess the efficacy of the exercise paradigm. NY immunohistochemistry on muscle cross-sections revealed that eccentric exercise significantly increased damage in older ( …

The Effects Of 6-Weeks Of Resistance Training On The Neuromuscular Fatigue Threshold In Older Adults, Nadia Emerson

Electronic Theses and Dissertations

Age-related deficits in muscle mass, strength, and function place an increased burden of work on existing skeletal muscle and may lead to early onset of neuromuscular fatigue (NMF) during activities of daily living. Resistance exercise (RE) is the proven method for improving neuromuscular function in healthy older adults. PURPOSE: To investigate the effects of 6 weeks of RE on the NMF threshold as well as strength and functional performance in older adults. METHODS: Twenty-four older adults were randomly assigned to 6 weeks of RE (EXE; n = 12; age 72 ± 6.3 y; BMI 28.4 kg/m2 ) or control (CONT; …

The Effects Of A Short Term Novel Aquatic Exercise Program On Functional Strength And Performance Of Older Adults, H. Scott Kieffer, Marie Attanasi Lehman, Danielle M. Veacock, Laura Korkuch

International Journal of Exercise Science

International Journal of Exercise Science 5(4) : 321-333, 2012. The purpose of this study was to determine the effects of a short-term novel multidimensional aquatic exercise program on functional abilities of healthy older adults. Twenty-six men and women (mean age 76.33 + 5.55 years) were recruited and assigned to an aquatic- (n = 15) or land-based (n = 11) training group. The aquatic training group completed a multidimensional water exercise program that incorporated resistance training, functional exercise movements and rudimentary aquatic plyometric activities. The active control group participated in a supervised land-based fitness program. Each exercise intervention was conducted over …

Peripheral Nerve Injury Increases Glutamate-Evoked Calcium Mobilization In Adult Spinal Cord Neurons, Suzanne Doolen, Camille B. Blake, Bret N. Smith, Bradley K. Taylor

Physiology Faculty Publications

BACKGROUND: Central sensitization in the spinal cord requires glutamate receptor activation and intracellular Ca2+ mobilization. We used Fura-2 AM bulk loading of mouse slices together with wide-field Ca2+ imaging to measure glutamate-evoked increases in extracellular Ca2+ to test the hypotheses that: 1. Exogenous application of glutamate causes Ca2+ mobilization in a preponderance of dorsal horn neurons within spinal cord slices taken from adult mice; 2. Glutamate-evoked Ca2+ mobilization is associated with spontaneous and/or evoked action potentials; 3. Glutamate acts at glutamate receptor subtypes to evoked Ca2+ transients; and 4. The magnitude of glutamate-evoked Ca2+ responses increases in the setting of …