Physiology Commons^™

Impact Of Short-Distance Road Transportation On Horse Health, Erica Jacquay

Theses and Dissertations--Veterinary Science

Horses are regularly transported across the United States; however, the reasons for travel, trip lengths, and management practices are not well characterized. While long distance transportation has been associated with increased incidences of health-related problems, the impact of short distance transportation on horse health is less understood. Notably, aged horses ( > 15 years) have an altered immune response following short-distance transportation, but this has yet to be compared to young horses. It is also unknown whether transportation stress would alter endocrine responses of horses with metabolic disorders, such as insulin dysregulation (ID) or pituitary pars intermedia dysfunction (PPID).

The objectives …

Disorganization Of Actin Within The Shafts Of Stereocilia Is A Key Difference Between Temporary And Permanent Noise-Induced Hearing Loss (Nihl), Shadan Hadi

Theses and Dissertations--Physiology

During sound stimulation, mechanosensory stereocilia of the auditory hair cell pivot around their bases, where their actin cores become denser and form rootlets protruding into the cuticular plate. It is believed that actin-based cuticular plate provides a stable mechanical support for stereocilia, while rootles are responsible for their pivotal flexibility and life-long resilience to mechanical stimuli. Not surprisingly, damage to the stereocilia bundles is known as a hallmark of permanent noise-induced hearing loss (NIHL). Yet, despite decades of NIHL studies, it is still unknown which ultrastructural changes in the stereocilia bundles are evoked directly by mechanical overstimulation.

Here, we explored …

Cyp6g2 Is The Major P450 Epoxidase Responsible For Juvenile Hormone Biosynthesis In Drosophila Melanogaster, Qiangqiang Jia, Liu Yang, Jiamin Wen, Suning Liu, Di Wen, Wei Luo, Weihua Wang, Subba R. Palli, Li Sheng

Entomology Faculty Publications

Background Juvenile hormones (JH) play crucial role in regulating development and reproduction in insects. The most common form of JH is JH III, derived from MF through epoxidation by CYP15 enzymes. However, in the higher dipterans, such as the fruitfly, Drosophila melanogaster, a bis-epoxide form of JHB3, accounted most of the JH detected. Moreover, these higher dipterans have lost the CYP15 gene from their genomes. As a result, the identity of the P450 epoxidase in the JH biosynthesis pathway in higher dipterans remains unknown.

Results In this study, we show that Cyp6g2 serves as the major JH epoxidase responsible for …

The Mechanoreceptor Piezo Is Required For Spermatogenesis In Bombyx Mori, Zhongjie Zhang, Xiaojing Liu, Bo Hu, Kai Chen, Ye Yu, Chenxin Sun, Dalin Zhu, Hua Bai, Subba Reddy Palli, Anjiang Tan

Entomology Faculty Publications

Background The animal sperm shows high diversity in morphology, components, and motility. In the lepidopteran model insect, the silkworm Bombyx mori, two types of sperm, including nucleate fertile eupyrene sperm and anucleate unfertile apyrene sperm, are generated. Apyrene sperm assists fertilization by facilitating the migration of eupyrene spermatozoa from the bursa copulatrix to the spermatheca. During spermatogenesis, eupyrene sperm bundles extrude the cytoplasm by peristaltic squeezing, while the nuclei of the apyrene sperm bundles are discarded with the same process, forming matured sperm.

Results In this study, we describe that a mechanoreceptor BmPiezo, the sole Piezo ortholog in B. mori, …

Acute Gastrointestinal Permeability After Traumatic Brain Injury In Mice Precedes A Bloom In Akkermansia Muciniphila Supported By Intestinal Hypoxia, Anthony J. Desana, Steven Estus, Terrence A. Barrett, Kathryn E. Saatman

Physiology Faculty Publications

Traumatic brain injury (TBI) increases gastrointestinal morbidity and associated mortality. Clinical and preclinical studies implicate gut dysbiosis as a consequence of TBI and an amplifier of brain damage. However, little is known about the association of gut dysbiosis with structural and functional changes of the gastrointestinal tract after an isolated TBI. To assess gastrointestinal dysfunction, mice received a controlled cortical impact or sham brain injury and intestinal permeability was assessed at 4 h, 8 h, 1 d, and 3 d after injury by oral administration of 4 kDa FITC Dextran prior to euthanasia. Quantification of serum fluorescence revealed an acute, …

Navigating Asynchronous Online Learning: The Impacts Of Active Learning And Assigned Group Work On Student Motivation, Belonging, And Inclusion, Shea Elisabeth Carr

Theses and Dissertations--Biology

Motivation, belonging, and inclusion are all critical factors for student success but can be difficult to support in asynchronous online courses. Active learning and required group work have been shown to increase student motivation in in-person and synchronous online courses, but little is known about their impact in online asynchronous settings. This dissertation aimed to 1) evaluate the effect of active learning on student motivation in an online asynchronous setting and 2) evaluate the impact of assigned group work on student motivation and perceptions of belonging and inclusion within the context of an online, asynchronous physiology laboratory course. It was …

Mechanisms Of Γδ T Cell Accumulation In Visceral Adipose Tissue With Aging, Sujata Mukherjee, Maria E. C. Bruno, Jason Oakes, Gregory S. Hawk, Arnold Stromberg, Donald A. Cohen, Marlene E. Starr

Markey Cancer Center Faculty Publications

γδ T cells are resident in visceral adipose tissue (VAT) where they show an age- associated increase in numbers and contribute to local and systemic chronic inflammation. However, regulation of this population and mechanisms for the age-dependent accumulation are not known. In this study, we identified a progressive trend of γδ T cell accumulation in VAT over the lifespan in mice and explored physiological mechanisms contributing to accumulation. Using isochronic parabiotic pairs of wild-type (WT) and T cell receptor delta knockout (TCRδ KO) mice at young and old age, we confirmed that VAT γδ T cells are predominately a tissue-resident …

Elongation Of Very Long Chain Fatty Acids-3 (Elovl3) Is Activated By Zhx2 And Is A Regulator Of Cell Cycle Progression, Kate Townsend Creasy, Hui Ren, Jieyun Jiang, Martha L. Peterson, Brett T. Spear

Markey Cancer Center Faculty Publications

Zinc fingers and homeoboxes 2 (Zhx2) are transcriptional regulators of liver gene expression with key functions in embryonic development as well as tissue regeneration in response to damage and disease, presumably through its control of target genes. Previous microarray data suggested that elongation of very long chain fatty acids-3 (Elovl3), a member of the ELOVL family of enzymes that synthesize very long chain fatty acids (VLCFAs), is a putative Zhx2 target gene. VLCFAs are core component of ceramides and other bioactive sphingolipids that are often dysregulated in diseases and regulate key cellular processes including proliferation. Since several previously identified Zhx2 …

Regulated Translocation Of Neutral Sphingomyelinase-2 To The Plasma Membrane Drives Insulin Resistance In Steatotic Hepatocytes, Salim S. El-Amouri, Alexander A. Karakashian, Erhard Bieberich, Mariana N. Nikolova‑Karakashian

Markey Cancer Center Faculty Publications

Abstract Obesity-associated diabetes is linked to the accumulation of ceramide in various organs, including the liver. The exact mechanisms by which ceramide contributes to diabetic pathology are unclear, but one proposed scenario is that ceramide accumulation may inhibit insulin signaling pathways. It is unknown however whether the excess ceramide is generated proximal to the insulin receptor, that is, at the plasma membrane (PM), where it could affect the insulin signaling pathway directly, or the onset of insulin resistance is due to ceramide- induced mitochondrial dysfunction and/or lipotoxicity. Using hepatic cell lines and primary cultures, gain- and loss- of function approach, …

Fructose Induced Khk-C Can Increase Er Stress Independent Of Its Effect On Lipogenesis To Drive Liver Disease In Diet-Induced And Genetic Models Of Nafld, Se-Hyung Park, Robert N. Helsley, Taghreed Fadhul, Jennifer L. S. Willoughby, Leila Noetzli, Ho-Chou Tu, Marie H. Solheim, Shiho Fujisaka, Hui Pan, Jonathan M. Dreyfuss, Joanna Bons, Jacob Rose, Christina D. King, Birgit Schilling, Aldons J. Lusis, Calvin Pan, Manoj Gupta, Rohit N. Kulkarni, Kevin Fitzgerald, Philip A. Kern, Senad Divanovic, C. Ronald Kahn, Samir Softic

Saha Cardiovascular Research Center Faculty Publications

Non-alcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome, and is estimated to affect one billion individuals worldwide. An increased intake of a high-fat diet (HFD) and sugar-sweetened beverages are risk-factors for NAFLD development, but how their combined intake promotes progression to a more severe form of liver injury is unknown. Here we show that fructose metabolism via ketohexokinase (KHK) C isoform leads to unresolved endoplasmic reticulum (ER) stress when coupled with a HFD intake. Conversely, a liver-specific knockdown of KHK in mice consuming fructose on a HFD is adequate to improve the NAFLD activity score and …

Asparagine Restriction Enhances Cd8+ T Cell Metabolic Fitness And Antitumoral Functionality Through An Nrf2-Dependent Stress Response, J. N. Rashida Gnanaprakasam, Bhavana Kushwaha, Lingling Liu, Xuyong Chen, Siwen Kang, Tingting Wang, Teresa A. Cassel, Christopher M. Adams, Richard M. Higashi, David A. Scott, Gang Xin, Zihai Li, Jun Yang, Andrew N. Lane, Teresa Whei-Mei Fan, Ji Zhang, Ruoning Wang

Markey Cancer Center Faculty Publications

Robust and effective T cell immune surveillance and cancer immunotherapy require proper allocation of metabolic resources to sustain energetically costly processes, including growth and cytokine production. Here, we show that asparagine (Asn) restriction on CD8+ T cells exerted opposing effects during activation (early phase) and differentiation (late phase) following T cell activation. Asn restriction suppressed activation and cell cycle entry in the early phase while rapidly engaging the nuclear factor erythroid 2-related factor 2 (NRF2)-dependent stress response, conferring robust proliferation and effector function on CD8+ T cells during differentiation. Mechanistically, NRF2 activation in CD8+ T cells conferred by Asn restriction …

Differential Inhibition Of Anaplerotic Pyruvate Carboxylation And Glutaminolysis-Fueled Anabolism Underlies Distinct Toxicity Of Selenium Agents In Human Lung Cancer, Teresa W-M Fan, Jason Winnike, Ahmad Al-Attar, Alex C. Belshoff, Pawel Lorkiewicz, Jin Lian Tan, Min Wu, Richard M. Higashi, Andrew N. Lane

Markey Cancer Center Faculty Publications

Past chemopreventive human trials on dietary selenium supplements produced controversial outcomes. They largely employed selenomethionine (SeM)-based diets. SeM was less toxic than selenite or methylseleninic acid (MSeA) to lung cancer cells. We thus investigated the toxic action of these Se agents in two non-small cell lung cancer (NSCLC) cell lines and ex vivo organotypic cultures (OTC) of NSCLC patient lung tissues. Stable isotope-resolved metabolomics (SIRM) using 13C6-glucose and 13C5,15N2-glutamine tracers with gene knockdowns were employed to examine metabolic dysregulations associated with cell type- and treatment-dependent phenotypic changes. Inhibition of key anaplerotic processes, pyruvate carboxylation (PyC) and glutaminolysis were elicited by …

Serum Amyloid A Augments The Atherogenic Effects Of Cholesteryl Ester Transfer Protein, Ailing Ji, Andrea C. Trumbauer, Victoria P. Noffsinger, Frederick C. De Beer, Nancy R. Webb, Lisa R. Tannock, Preetha Shridas

Saha Cardiovascular Research Center Faculty Publications

Serum amyloid A (SAA) is predictive of CVD in humans and causes atherosclerosis in mice. SAA has many proatherogenic effects in vitro. However, HDL, the major carrier of SAA in the circulation, masks these effects. The remodeling of HDL by cholesteryl ester transfer protein (CETP) liberates SAA restoring its proinflammatory activity. Here, we investigated whether deficiency of SAA suppresses the previously described proatherogenic effect of CETP. ApoE¡/¡ mice and apoE¡/¡ mice deficient in the three acute-phase isoforms of SAA (SAA1.1, SAA2.1, and SAA3; “apoE¡/¡ SAA-TKO”) with and without adeno-associated virus-mediated expression of CETP were studied. There was no effect of …

Life Stressors And Immune Aging: Protective Effects Of Cognitive Reappraisal, Rebecca G. Reed, Steven R. Presnell, Ahmad Al-Attar, Charles T. Lutz, Suzanne C. Segerstrom

Markey Cancer Center Faculty Publications

Stressful life events may accelerate aspects of immune aging, but habitual use of an adaptive emotion regulation strategy, cognitive reappraisal, may attenuate these effects. This study examined whether cognitive reappraisal moderates the associations between life stressor frequency and stressor desirability on aspects of immune aging, including late-differentiated CD8+ T and natural killer (NK) cells and inflammatory markers (IL-6, TNF-α, and CRP), both between and within people in a longitudinal sample of 149 older adults (mean age = 77.8, range: 64–92 years). Participants reported stressful life events, use of cognitive reappraisal, and provided blood semiannually for up to 5 years to …

The Importance Of Translationally Evaluating Steroid Hormone Contributions To Substance Use, Erin E. Maher, Ashley Strzelecki, Jessica J. Weafer, Cassandra D. Gipson

Markey Cancer Center Faculty Publications

Clinically, women appear to be more susceptible to certain aspects of substance use disorders (SUDs). The steroid hormones 17β-estradiol (E2) and progesterone (Pg) have been linked to women-specific drug behaviors. Here, we review clinical and preclinical studies investigating how cycling ovarian hormones affect nicotine-, cocaine-, and opioid-related behaviors. We also highlight gaps in the literature regarding how synthetic steroid hormone use may influence drug-related behaviors. In addition, we explore how E2 and Pg are known to interact in brain reward pathways and provide evidence of how these interactions may influence drug-related behaviors. The synthesis of this review demonstrates the critical …

Impact Of The Dimethyl Sulfoxide Reductase Superfamily On The Evolution Of Biogeochemical Cycles, Michael Wells, Minjae Kim, Denise M. Akob, Partha Basu, John F. Stolz

UK CARES Faculty Publications

The dimethyl sulfoxide reductase (or MopB) family is a diverse assemblage of enzymes found throughout Bacteria and Archaea. Many of these enzymes are believed to have been present in the last universal common ancestor (LUCA) of all cellular lineages. However, gaps in knowledge remain about how MopB enzymes evolved and how this diversification of functions impacted global biogeochemical cycles through geologic time. In this study, we perform maximum likelihood phylogenetic analyses on manually curated comparative genomic and metagenomic data sets containing over 47,000 distinct MopB homologs. We demonstrate that these enzymes constitute a catalytically and mechanistically diverse superfamily defined not …

Loss Of Peroxiredoxin Iv Protects Mice From Azoxymethane/Dextran Sulfate Sodium-Induced Colorectal Cancer Development, Pratik Thapa, Hong Jiang, Na Ding, Yanning Hao, Aziza Alshahrani, Eun Young Lee, Junichi Fujii, Qiou Wei

Markey Cancer Center Faculty Publications

Peroxiredoxin IV (Prx4), a typical two-cysteine-containing member of the peroxidase family, functions as an antioxidant to maintain cellular redox homeostasis through the reduction of reactive oxygen species (ROS) via cycles of oxidation–reduction reactions. Under oxidative stress, all Prxs including Prx4 are inactivated as their catalytic cysteines undergo hyperoxidation, and hyperoxidized two-cysteine Prxs can be exclusively repaired and revitalized through the reduction cycle catalyzed by sulfiredoxin (Srx). Previously, we showed that Prx4 is a preferred substrate of Srx, and knockout of Srx in mice leads to resistance to azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon carcinogenesis. To further understand the significance of the …

Chronic Environmental Circadian Disruption Increases Atherosclerosis And Dyslipidemia In Female, But Not Male, Apolipoproteine-Deficient Mice, Jeffrey M. Chalfant, Deborah A. Howatt, Victoria B. Johnson, Lisa R. Tannock, Alan Daugherty, Julie S. Pendergast

Saha Cardiovascular Research Center Faculty Publications

Shift work chronically disrupts circadian rhythms and increases the risk of developing cardiovascular disease. However, the mechanisms linking shift work and cardiovascular disease are largely unknown. The goal of this study was to investigate the effects of chronically shifting the light-dark (LD) cycle, which models the disordered exposure to light that may occur during shift work, on atherosclerosis. Atherosclerosis is the progressive accumulation of lipid-filled lesions within the artery wall and is the leading cause of cardiovascular disease. We studied ApolipoproteinE-deficient (ApoE−/−) mice that are a well-established model of atherosclerosis. Male and female ApoE−/− mice were housed in control 12L:12D …

Critical Role Of The Sulfiredoxin-Peroxiredoxin Iv Axis In Urethane-Induced Non-Small Cell Lung Cancer, Yanning Hao, Hong Jiang, Pratik Thapa, Na Ding, Aziza Alshahrani, Junichi Fujii, Michel B. Toledano, Qiou Wei

Markey Cancer Center Faculty Publications

Non-small cell lung cancer (NSCLC), the most common type of lung cancer, etiologically associates with tobacco smoking which mechanistically contributes to oxidative stress to facilitate the occurrence of mutations, oncogenic transformation and aberrantly activated signaling pathways. Our previous reports suggested an essential role of Sulfiredoxin (Srx) in promoting the development of lung cancer in humans, and was causally related to Peroxiredoxin IV (Prx4), the major downstream substrate and mediator of Srx-enhanced signaling. To further explore the role of the Srx-Prx4 axis in de novo lung tumorigenesis, we established Prx4−/− and Srx−/−/Prx4−/− mice in pure FVB/N background. Together with wild-type litter …

Effect Of Reflex And Mechanical Decreases In Skin Perfusion On Thermal- And Agonist-Induced Eccrine Sweating In Humans, Kristen Metzler-Wilson, Milie M. Fang, Kenan Alibegovic, James W. Daggett, Seetharam C. Narra, Robert P. Dazé, Olivia G. Miller, Thad E. Wilson

UK CARES Faculty Publications

In humans, skin blood flux (SkBF) and eccrine sweating are tightly coupled, suggesting common neural control and regulation. This study was designed to separate these two sympathetic nervous system end-organ responses via nonadrenergic SkBF- decreasing mechanical perturbations during heightened sudomotor drive. We induced sweating physiologically via whole body heat stress using a high-density tube-lined suit (protocol 1; 2 women, 4 men), and pharmacologically via forearm intradermal microdialysis of two steady-state doses of a cholinergic agonist, pilocarpine (protocol 2; 4 women, 3 men). During sweating induction, we decreased SkBF via three mechanical perturbations: arm and leg dependency to engage the cutaneous …

Increasing Efficiency Of Finishing Beef Production: Strategies To Optimize Starch Digestion, Improve Flake Quality, And Reduce Methane Emissions, Ronald J. Trotta

Theses and Dissertations--Animal and Food Sciences

To continue to meet the demands of increasing food production and environmental sustainability, new strategies are needed to enhance the efficiency of finishing cattle production. A review of the literature identified several nutritional and physiological constraints that limit the ability for cattle to digest starch and absorb glucose from the small intestine. Comparative sequencing analyses revealed a missing region of the sucrase-isomaltase protein which could affect the capacity for starch digestion in cattle. Post-flaking sampling and handling recommendations were generated based on a series of experiments to improve estimates of starch availability and flaking consistency for commercial feedlots and laboratories. …

Reliability And Validity Of A Commercial Running Power Meter To Indicate Metabolic Workload During Endurance Running, James Harris Hudgins Iii

Theses and Dissertations--Kinesiology and Health Promotion

Commercial running power (RP) meters may provide endurance runners and coaches with improved precision for monitoring running intensity. Cyclists rely upon the relationship between cycling power and metabolic demand to regulate physiological intensity during training and racing, independent of changes in the physical environment (e.g., terrain, wind). Research demonstrates strong reliability and validity for a specific RP meter to indicate metabolic demand within controlled running conditions. However, several potential influences on this relationship have not been investigated. Therefore, four studies were conducted with the following aims:

- Study 1: Determine the inter-limb reliability and validity of a single-limb-based RP meter …

Age-Associated Increase Of Gamma Delta T Cells In Visceral Adipose Tissue And Mechanisms Of Their Accumulation, Sujata Mukherjee

Theses and Dissertations--Pharmacology and Nutritional Sciences

Chronic systemic inflammation, known as inflammaging is considered a hallmark of aging and associated diseases. While adipose tissue has long been considered only as a caloric reservoir regulating systemic energy homeostasis, research in the past couple of decades substantiate its endocrine function to secrete an array of inflammatory mediators and hormones, which have physiological effects on multiple organ systems, and contribute to inflammaging. Redistribution of adipose tissue from subcutaneous to visceral depots, changes in the immune profile and the chronic inflammatory state are among the major sources of adipose tissue dysfunction with aging.

This dissertation is focused on identifying and …

Rewired Metabolism In Apoe4 Microglia: Implications For Inflammation And Neurodegeneration, Nicholas A. Devanney

Theses and Dissertations--Physiology

Among the earliest changes to occur in Alzheimer’s disease, metabolic dysfunction and chronic neuroinflammation are now known to be major driving forces in disease progression. The paradigm of ‘immunometabolism’ seeks to bridge these two facets, positing that metabolic transformations are indispensable in determining the response of immune cells, such as microglia – the brain’s resident immune population. Proinflammatory stimulation of microglia leads to a shift away from mitochondrial respiration towards a dramatic upregulation of the glycolysis pathway for energy production. This glycolytic burst provides microglia with a rapid supply of ATP, but comes at a cost, as utilizing glucose to …

Best3-Mediated Mekk2/3 Activation: A Novel Therapeutic Target In Aortopathies, Tatiana Zyrianova, Benjamin Lopez, Kathlyn Zou, Charles Gu, Dayna Pham, Sriharsha Talapaneni, Christopher M. Waters, Riccardo Olcese, Andreas Schwingshackl

Saha Cardiovascular Research Center Faculty Publications

Influenza-A virus (IAV) infects yearly an estimated one billion people worldwide, resulting in 300,000–650,000 deaths. Preventive vaccination programs and antiviral medications represent the mainstay of therapy, but with unacceptably high morbidity and mortality rates, new targeted therapeutic approaches are urgently needed. Since inflammatory processes are commonly associated with measurable changes in the cell membrane potential (Em), we investigated whether Em hyperpolarization via TREK-1 (K2P 2.1) K þ channel activation can protect against influenza-A virus (IAV)-induced pneumonia. We infected mice with IAV, which after 5 days caused 10–15% weight loss and a decrease in spontaneous activity, representing a clinically relevant infection. …

Multilevel Phenotypic Integration Of Metabolism And Behavior In House Sparrows And Mice, Tim Salzman

Theses and Dissertations--Biology

Patterns of multilevel variation in behavior, both within and among individuals, raise challenging questions about underlying mechanisms and the selective pressures acting on them. One intriguing hypothesis is that physiology shows parallel multilevel variation, and so might represent a latent trait that integrates multilevel behavioral responses. For example, foraging acquires the fuel needed to maintain metabolism, and in turn, an individual’s metabolism affects expression of foraging, and other, behaviors. Metabolism and behavior thus might coevolve to become integrated traits. Despite the appeal of this hypothesis, numerous investigations into the link between metabolism and behavior have yielded largely equivocal results.

To …

Bilirubin Levels Are Negatively Correlated With Adiposity In Obese Men And Women, And Its Catabolized Product, Urobilin, Is Positively Associated With Insulin Resistance, Zachary A. Kipp, Mei Xu, Evelyn A. Bates, Wang-Hsin Lee, Philip A. Kern, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Bilirubin levels in obese humans and rodents have been shown to be lower than in their lean counterparts. Some studies have proposed that the glucuronyl UGT1A1 enzyme that clears bilirubin from the blood increases in the liver with obesity. UGT1A1 clearance of bilirubin allows more conjugated bilirubin to enter the intestine, where it is catabolized into urobilin, which can be then absorbed via the hepatic portal vein. We hypothesized that when bilirubin levels are decreased, the urobilin increases in the plasma of obese humans, as compared to lean humans. To test this, we measured plasma levels of bilirubin and urobilin, …

Advanced Age And Neurotrauma Diminish Glutathione And Impair Antioxidant Defense After Spinal Cord Injury, Andrew N. Stewart, Ethan P. Glaser, Caitlin A. Mott, William M. Bailey, Patrick G. Sullivan, Samir P. Patel, John C. Gensel

Physiology Faculty Publications

Advanced age at the time of spinal cord injury (SCI) exacerbates damage from reactive oxygen species (ROS). Mechanisms underlying this age-dependent response are not well understood and may arise from decreased antioxidant defense. We investigated how spinal cord levels of the antioxidant glutathione (GSH), and its regulation, change with age and SCI. GSH is used by GSH peroxidase to sequester ROS and is recycled by GSH reductase. Male and female, 4- and 14-month-old (MO) mice received a 60 kDyn contusion SCI, and the levels of GSH and its regulatory enzymes were evaluated at one and three days post-injury (dpi). The …

Apoe Genetics Influence Murine Gut Microbiome, Diana J. Zajac, Stefan J. Green, Lance A. Johnson, Steven Estus

Physiology Faculty Publications

Apolipoprotein E (APOE) alleles impact pathogenesis and risk for multiple human diseases, making them primary targets for disease treatment and prevention. Previously, we and others reported an association between APOE alleles and the gut microbiome. Here, we evaluated effects of APOE heterozygosity and tested whether these overall results extended to mice maintained under ideal conditions for microbiome analyses. To model human APOE alleles, this study used APOE targeted replacement (TR) mice on a C57Bl/6 background. To minimize genetic drift, homozygous APOE3 mice were crossed to homozygous APOE2 or homozygous APOE4 mice prior to the study, and the resulting …

Maximal Strength Training Increases Metabolic Energy Expenditure In Sedentary Adults Classified As Obese, Robert E. Anderson Iii

Theses and Dissertations--Nutrition and Food Systems

Background: Metabolic adaptations reduce resting and non-resting energy expenditure to account for approximately 120 kcal/day. Weight loss promotes greater skeletal muscle efficiency, reducing the energy cost of physical activity and is correlated with declines in skeletal muscle glucose oxidation. Maximal Strength Training (MST) has the potential to upregulate glucose utilization and may offset these metabolic adaptations. Objective: To determine if MST offsets markers of metabolic adaptation by increasing resting and non-resting energy expenditure in sedentary individuals classified as obese. Methods: Five (5) participants (2 females, 3 males), ages 18-35 years, with obesity (BMI 30–45 kg/m2) were enrolled in an 8-week …