Physiology Commons^™

Serum Amyloid A Binds To Gibrin(Ogen), Promoting Fibrin Amyloid Formation, Martin J. Page, Greig J. A. Thomson, J. Massimo Nunes, Anna-Mart Engelbrecht, Theo A. Nell, Willem J. S. De Villiers, Maria C. De Beer, Lize Engelbrecht, Douglas B. Kell, Etheresia Pretorius

Physiology Faculty Publications

Complex associations exist between inflammation and thrombosis, with the inflammatory state tending to promote coagulation. Fibrinogen, an acute phase protein, has been shown to interact with the amyloidogenic ß-amyloid protein of Alzheimer’s disease. However, little is known about the association between fibrinogen and serum amyloid A (SAA), a highly fibrillogenic protein that is one of the most dramatically changing acute phase reactants in the circulation. To study the role of SAA in coagulation and thrombosis, in vitro experiments were performed where purified human SAA, in concentrations resembling a modest acute phase response, was added to platelet-poor plasma (PPP) and whole …

A Hindbrain Inhibitory Microcircuit Mediates Vagally-Coordinated Glucose Regulation, Carie R. Boychuk, Katalin Cs. Smith, Laura E. Peterson, Jeffery A. Boychuk, Corwin R. Butler, Isabel D. Derera, John J. Mccarthy, Bret N. Smith

Physiology Faculty Publications

Neurons in the brainstem dorsal vagal complex integrate neural and humoral signals to coordinate autonomic output to viscera that regulate a variety of physiological functions, but how this circuitry regulates metabolism is murky. We tested the hypothesis that premotor, GABAergic neurons in the nucleus tractus solitarius (NTS) form a hindbrain micro-circuit with preganglionic parasympathetic motorneurons of the dorsal motor nucleus of the vagus (DMV) that is capable of modulating systemic blood glucose concentration. In vitro, neuronal activation or inhibition using either excitatory or inhibitory designer receptor exclusively activated by designer drugs (DREADDs) constructs expressed in GABAergic NTS neurons increased …

Transcranial Direct Current Stimulation Of Motor Cortex Enhances Running Performance., Seung-Bo Park, Dong Jun Sung, Bokyung Kim, Sojung Kim, Joung-Kyue Han

Faculty Scholarship for the College of Science & Mathematics

Transcranial direct current stimulation (tDCS) is a technique used to modulate neuronal excitability through non-invasive brain stimulation that can enhance exercise performance. We hypothesize that tDCS would improve submaximal running time to exhaustion (TTE) and delay the increase in the rating of perceived exertion (RPE) over time. We also hypothesize that tDCS would not lead to difference in cardiorespiratory responses. We employed a randomized, single-blinded, and counterbalanced design in which 10 trained men participated. After receiving either 20 min of 1.98 mA anodal tDCS applied over the primary motor cortex (M1) or sham-operated control on separate days, participants completed a …

Apolipoprotein E4 Alters Astrocyte Fatty Acid Metabolism And Lipid Droplet Formation, Brandon C. Farmer, Jude Kluemper, Lance A. Johnson

Physiology Faculty Publications

Lipid droplets (LDs) serve as energy rich reservoirs and have been associated with apolipoprotein E (APOE) and neurodegeneration. The E4 allele of APOE (E4) is the strongest genetic risk factor for the development of late onset Alzheimer’s disease (AD). Since both E4 carriers and individuals with AD exhibit a state of cerebral lipid dyshomeostasis, we hypothesized that APOE may play a role in regulating LD metabolism. We found that astrocytes expressing E4 accumulate significantly more and smaller LDs compared to E3 astrocytes. Accordingly, expression of perilipin-2, an essential LD protein component, was higher in E4 astrocytes. We then …

Identification Of The Alternative Oxidase Gene And Its Expression In The Copepod Tigriopus Californicus, Allison Mcdonald, Carly E. Tward, Willie Cygelfarb, Jaspreet Singh

Biology Faculty Publications

In addition to the typical electron transport system (ETS) in animal mitochondria responsible for oxidative phosphorylation, in some species there exists an alternative oxidase (AOX) pathway capable of catalyzing the oxidation of ubiquinol and the reduction of oxygen to water. The discovery of AOX in animals is recent and further investigations into its expression, regulation, and physiological role have been hampered by the lack of a tractable experimental model organism. Our recent DNA database searches using bioinformatics revealed an AOX sequence in several marine copepods including Tigriopus californicus. This species lives in tidepools along the west coast of North …

Association Between Perceived Physical Activity And Cognitive Function In Older Adults, Paul D. Loprinzi, Emily Frith

Faculty and Student Publications

© The Author(s) 2018. There is irrefutable evidence that regular participation in physical activity is favorably associated with numerous positive health outcomes, including cognitive function. Emerging work suggests that perceived physical activity, independent of actual physical activity behavior, is inversely associated with mortality risk. In this study, we evaluate whether perceived physical activity, independent of actual physical activity, is associated with cognitive function, a robust indicator of mortality risk. Data from the cross-sectional 1999–2002 National Health and Nutrition Examination Survey were employed (N = 2352; 60+ years of age). Actual physical activity was assessed via a validated survey. Perceived physical …

Acute Treadmill Exercise Discriminately Improves The Skeletal Muscle Insulin-Stimulated Growth Signaling Responses In Mice Lacking Redd1, Cory M. Dungan, Bradley S. Gordon, David L Williamson

Physical Therapy Faculty Publications

A loss of the regulated in development and DNA damage 1 (REDD1) hyperactivates mechanistic Target of Rapamycin Complex 1 (mTORC1) reducing insulin‐stimulated insulin signaling, which could provide insight into mechanisms of insulin resistance. Although aerobic exercise acutely inhibits mTORC1 signaling, improvements in insulin‐stimulated signaling are exhibited. The goal of this study was to determine if a single bout of treadmill exercise was sufficient to improve insulin signaling in mice lacking REDD1. REDD1 wildtype (WT) and REDD1 knockout (KO) mice were acutely exercised on a treadmill (30 min, 20 m/min, 5% grade). A within animal noninsulin‐to‐insulin‐stimulated percent change in skeletal muscle …

Human Skeletal Muscle Macrophages Increase Following Cycle Training And Are Associated With Adaptations That May Facilitate Growth, R. Grace Walton, Kate Kosmac, Jyothi Mula, Christopher S. Fry, Bailey D. Peck, Jason S. Groshong, Brian S. Finlin, Beibei Zhu, Philip A. Kern, Charlotte A. Peterson

Center for Muscle Biology Faculty Publications

Skeletal muscle macrophages participate in repair and regeneration following injury. However, their role in physiological adaptations to exercise is unexplored. We determined whether endurance exercise training (EET) alters macrophage content and characteristics in response to resistance exercise (RE), and whether macrophages are associated with other exercise adaptations. Subjects provided vastus lateralis biopsies before and after one bout of RE, after 12 weeks of EET (cycling), and after a final bout of RE. M2 macrophages (CD11b+/CD206+) did not increase with RE, but increased in response to EET (P < 0.01). Increases in M2 macrophages were positively correlated with fiber hypertrophy (r = 0.49) and satellite cells (r = 0.47). M2c macrophages (CD206+/CD163+) also increased following EET (P < 0.001), and were associated with fiber hypertrophy (r = 0.64). Gene expression was quantified using NanoString. Following EET, the change in M2 macrophages was positively associated with changes in HGF, IGF1, and extracellular matrix genes. EET decreased expression of IL6 (P < 0.05), C/EBPβ (P < 0.01), and MuRF (P < 0.05), and increased expression of IL-4 (P < 0.01), TNFα (P < 0.01) and the TWEAK receptor FN14 (P < 0.05). The change in FN14 gene expression was inversely associated with changes in C/EBPβ (r = −0.58) and MuRF (r = −0.46) following EET. In cultured human myotubes, siRNA inhibition of FN14 increased expression of C/EBPβ (P < 0.05) and MuRF (P < 0.05). Our data suggest that macrophages contribute to the muscle response to EET, potentially including modulation of TWEAK-FN14 signaling.

Cerebrovascular Smooth Muscle Cells As The Drivers Of Intramural Periarterial Drainage Of The Brain, Roxana Aldea, Roy O. Weller, Donna M. Wilcock, Roxana O Carare, Giles Richardson

Physiology Faculty Publications

The human brain is the organ with the highest metabolic activity but it lacks a traditional lymphatic system responsible for clearing waste products. We have demonstrated that the basement membranes of cerebral capillaries and arteries represent the lymphatic pathways of the brain along which intramural periarterial drainage (IPAD) of soluble metabolites occurs. Failure of IPAD could explain the vascular deposition of the amyloid-beta protein as cerebral amyloid angiopathy (CAA), which is a key pathological feature of Alzheimer's disease. The underlying mechanisms of IPAD, including its motive force, have not been clarified, delaying successful therapies for CAA. Although arterial pulsations from …

Antisense Oligonucleotides Targeting Angiotensinogen: Insights From Animal Studies, Chia-Hua Wu, Ya Wang, Murong Ma, Adam E. Mullick, Rosanne M. Crooke, Mark J. Graham, Alan Daugherty, Hong S. Lu

Saha Cardiovascular Research Center Faculty Publications

Angiotensinogen (AGT) is the unique substrate of all angiotensin peptides. We review the recent preclinical research of AGT antisense oligonucleotides (ASOs), a rapidly evolving therapeutic approach. The scope of the research findings not only opens doors for potentially new therapeutics of hypertension and many other diseases, but also provides insights into understanding critical physiological and pathophysiological roles mediated by AGT.

Enhancing Cognitive Engagement Of Pre-Clinical Undergraduate Medical Students Via Video Cases And Interactive Quizzes In Problem-Based Learning, Syeda Sadia Fatima, Kulsoom Ghias, Kauser Jabeen, Saniya Sabzwari

Department of Biological & Biomedical Sciences

Background: Problem-based learning (PBL) is one of the main pedagogical approaches utilized in the undergraduate medical education (UGME) program at a private medical college in Karachi, Pakistan. Video-enhanced cases and formative assessments were introduced at the end of PBL sessions to evaluate their effectiveness in enhancing student engagement.
Methods: A mixed methods study was conducted with Year 2 medical students (n=102; divided into 11 groups) and faculty (n=11) facilitating the PBL process. Of the 10 PBL cases, five were converted to video-enhanced cases and five were kept as paper-based, “traditional” cases. “Micro” videos were used to introduce clinical scenarios, augmented …

Anthocynanins, Lily Lincoln, Maxkenzie Taticek

Natural Sciences Student Research Presentations

This slide presentation for the Natural Sciences Poster Session at Parkland College summarizes anthoxyanins, flavonoid water soluble pigments in plants like blueberries and other blue and purple plants -- their chemical composition, role in plants, and benefits as antioxidants.

Acute Exercise And Mindfulness Meditation On Learning And Memory: Randomized Controlled Intervention, Malina Austin, Paul D. Loprinzi

Faculty and Student Publications

© 2019 The Author(s). Background: The purpose of this experiment was to evaluate the potential combined effects of acute exercise and mindfulness mediation on episodic memory. Methods: All data collection occurred in the authors’ laboratory (January to May of 2019). In this three-arm, within-subject design, participants (N=20; Mage=21.6 years) completed three counterbalanced laboratory visits, including Exercise Only, Exercise + Meditation and Control. Learning and memory were assessed from a word-list task. A one-factor repeated-measures ANOVA was computed for two memory outcomes, including the learning outcome (average performance across the 6 trials) and the long-term memory recall (10-minute delay). Results: The …

Machine-Learning To Stratify Diabetic Patients Using Novel Cardiac Biomarkers And Integrative Genomics, Quincy A. Hathaway, Skyler M. Roth, Mark V. Pinti, Daniel C. Sprando, Amina Kunovac, Andrya J. Durr, Chris C. Cook, Garret K. Fink, Tristen B. Cheuvront, Jasmine H. Grossman, Ghadah A. Aljahli, Andrew D. Taylor, Andrew P. Giromini, Jessica L. Allen, John M. Hollander

Faculty & Staff Scholarship

Background: Diabetes mellitus is a chronic disease that impacts an increasing percentage of people each year. Among its comorbidities, diabetics are two to four times more likely to develop cardiovascular diseases. While HbA1c remains the primary diagnostic for diabetics, its ability to predict long-term, health outcomes across diverse demographics, ethnic groups, and at a personalized level are limited. The purpose of this study was to provide a model for precision medicine through the implementation of machine-learning algorithms using multiple cardiac biomarkers as a means for predicting diabetes mellitus development. Methods: Right atrial appendages from 50 patients, 30 non-diabetic and 20 …

Activation Of Adenosine A2a But Not A2b Receptors Is Involved In Uridine Adenosine Tetraphosphate-Induced Porcine Coronary Smooth Muscle Relaxation, Changyan Sun, Tong Jiao, Daphne Merkus, Dirk J. Duncker, S. Jamal Mustafa, Zhichao Zhou

Faculty & Staff Scholarship

Activation of both adenosine A2A and A2B receptors (A2BR) contributes to coronary vasodilation. We previously demonstrated that uridine adenosine tetraphosphate (Up4A) is a novel vasodilator in the porcine coronary microcirculation, acting mainly on A2AR in smooth muscle cells (SMC). We further investigated whether activation of A2BR is involved in Up4A-mediated coronary SMC relaxation. Both A2AR and A2BR may stimulate H2O2 production leading to activation of KATP channels in SMCs, we also studied the involvement of H2O2 and KATP channels in Up4A-mediated effect. Coronary small arteries dissected from the apex of porcine hearts were mounted on wire myograph for Up4A concentration …

Data Collection Curated With An Application Ontology Describes The Methods And Results Upon Performing An Ex-Vivo Voltage-Clamp Assay On Outer Hair Cells Of The Mammalian Cochlea, Brenda Farrell, Jason Bengtson

Research Data

This data collection describes the electrical properties of outer hair cells isolated from the mammalian cochlea of the domestic guinea pig. This data was obtained by performing whole-cell patch clamp voltage clamp assay on cells and monitoring the electrical admittance during a DC voltage ramp. The membrane capacitance was then calculated at each membrane potential from this admittance, and the voltage-independent and voltage-dependent membrane capacitance was determined upon further analysis. In some case the DC conductance was also measured by interrogation of the cell with voltage-step function which was calculated from the change in the mean steady-state current with respect …

A Hybrid Cognitive Architecture With Primal Affect And Physiology, Christopher L. Dancy

Faculty Journal Articles

Though computational cognitive architectures have been used to study several processes associated with human behavior, the study of integration of affect and emotion in these processes has been relatively sparse. Theory from affective science and affective neuroscience can be used to systematically integrate affect into cognitive architectures, particularly in areas where cognitive system behavior is known to be associated with physiological structure and behavior. I introduce a unified theory and model of human behavior that integrates physiology and primal affect with cognitive processes in a cognitive architecture. This new architecture gives a more tractable, mechanistic way to simulate affect-cognition interactions …

Body Condition Helps To Explain Metabolic Rate Variation In Wolf Spiders, Stella F. Uiterwaal, John P. Delong

School of Biological Sciences: Faculty Publications

1. Metabolism is the fundamental process that powers life. Understanding what drives metabolism is therefore critical to our understanding of the ecology and behavior of organisms in nature.

2. Metabolic rate generally scales with body size according to a power law. However, considerable unexplained variation in metabolic rate remains after accounting for body mass with scaling functions.

3. We measured resting metabolic rates (oxygen consumption) of 227 field-caught wolf spiders. Then, we tested for effects of body mass, species, and body condition on metabolic rate.

4. Metabolic rate scales with body mass to the 0.85 power in these wolf spiders, …

An Exploratory Study Of Extremesport Athletes’ Nature Interactions:From Well-Being To Pro-Environmental Behavior, Tadhg Eoghan Macintyre, Andree M. Walkin, Juergen Beckmann, Giovanna Calogiuri, Susan Gritzka, Greig Oliver, Aoife Donnelly, Giles Warrington

Articles

Traditionally, perceptions about extreme sport athletes being disconnected fromnature and a risk-taking population have permeated the research literature. Drawingupon theoretical perspectives from environmental, sport, organizational and positivepsychology, this qualitative study attempts to explore the lived experiences of fourmale and four female extreme sport athletes. The purpose of this study was togain insight and understanding into the individuals’ attitudes toward the benefits ofextreme sport activities for well-being, resilience and pro-environmental behavior. Eightparticipants (Mean age = 40.5 years;SD=±12.9) provided written informed consentto partake in semi-structured interviews. Each athlete provided written consented toallow the publication of their identifiable data and in order to …

Vitellogenin Receptor As A Target For Tick Control: A Mini-Review, Robert D. Mitchell Iii, Daniel E. Sonenshine, Adalberto A. Pérez De León

Biological Sciences Faculty Publications

While much effort has been put into understanding vitellogenesis in insects and other organisms, much less is known of this process in ticks. There are several steps that facilitate yolk formation in developing oocytes of which the vitellogenin receptor (VgR) is a key component. The tick VgR binds vitellogenin (Vg) circulating in the hemolymph to initiate receptor-mediated endocytosis and its transformation into vitellin (Vn). The conversion of Vg into Vn, the final form of the yolk protein, occurs inside oocytes of the female tick ovary. Vn is critical to tick embryos since it serves as the nutritional source for their …

Autonomic And Redox Imbalance Correlates With T-Lymphocyte Inflammation In A Model Of Chronic Social Defeat Stress, Cassandra M. Moshfegh, Safwan K. Elkhatib, Christopher W. Collins, Allison J. Kohl, Adam J. Case

Journal Articles: Cellular & Integrative Physiology

Patients diagnosed with post-traumatic stress disorder (PTSD) are at a significantly elevated risk of developing comorbid inflammatory conditions, but the mechanisms underlying this predilection remain unclear. Our previous work has shown that T-lymphocytes exposed to elevated levels of norepinephrine (NE) displayed a pro-inflammatory signature reminiscent of an autoreactive phenotype. With this, we hypothesized that the increased sympathetic tone observed during psychological trauma may be promoting pro-inflammatory T-lymphocytes, which causes a predisposition to comorbid inflammatory conditions. Here, we examined the consequences of psychological trauma on splenic T-lymphocytes using a mouse model of repeated social defeat stress. Social defeat led to anxiety-like …

Redox Biology In Physiology And Disease, Matthew C. Zimmerman, Adam J. Case

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

Central Glucagon-Like Peptide-1 Receptor Signaling Via Brainstem Catecholamine Neurons Counteracts Hypertension In Spontaneously Hypertensive Rats, Kenichi Katsurada, Masanori Nakata, Toshinobu Saito, Boyang Zhang, Yuko Maejima, Shyam Sundar Nandi, Neeru M. Sharma, Kaushik K. Patel, Kazuomi Kario, Toshihiko Yada

Journal Articles: Cellular & Integrative Physiology

Glucagon-like peptide-1 receptor (GLP-1R) agonists, widely used to treat type 2 diabetes, reduce blood pressure (BP) in hypertensive patients. Whether this action involves central mechanisms is unknown. We here report that repeated lateral ventricular (LV) injection of GLP-1R agonist, liraglutide, once daily for 15 days counteracted the development of hypertension in spontaneously hypertensive rats (SHR). In parallel, it suppressed urinary norepinephrine excretion, and induced c-Fos expressions in the area postrema (AP) and nucleus tractus solitarius (NTS) of brainstem including the NTS neurons immunoreactive to dopamine beta-hydroxylase (DBH). Acute administration of liraglutide into fourth ventricle, the area with easy access to …

Redox-Sensitive Calcium/Calmodulin-Dependent Protein Kinase Iiα In Angiotensin Ii Intra-Neuronal Signaling And Hypertension, Urmi Basu, Adam J. Case, Jinxu Liu, Jun Tian, Yulong Li, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Dysregulation of brain angiotensin II (AngII) signaling results in modulation of neuronal ion channel activity, an increase in neuronal firing, enhanced sympathoexcitation, and subsequently elevated blood pressure. Studies over the past two decades have shown that these AngII responses are mediated, in part, by reactive oxygen species (ROS). However, the redox-sensitive target(s) that are directly acted upon by these ROS to execute the AngII pathophysiological responses in neurons remain unclear. Calcium/calmodulin-dependent protein kinase II (CaMKII) is an AngII-activated intra-neuronal signaling protein, which has been suggested to be redox sensitive as overexpressing the antioxidant enzyme superoxide dismutase attenuates AngII-induced activation of …

Exercise Training Prevents The Perivascular Adipose Tissue-Induced Aortic Dysfunction With Metabolic Syndrome, Evan Devallance, Kayla W. Branyan, Kent C. Lemaster, Ray Anderson, Kent L. Marshall, I. Mark Olfert, David M. Smith, Eric E. Kelly, Randy W. Bryner, Jefferson C. Frisbee, Paul D. Chantler

Faculty & Staff Scholarship

The aim of the study was to determine the effects of exercise training on improving the thoracic perivascularadipose tissue (tPVAT) phenotype (inflammation, oxidative stress, and proteasome function) in metabolic syn-drome and its subsequent actions on aortic function.Methods:Lean and obese (model of metabolic syndrome) Zucker rats (n=8/group) underwent 8-weeks ofcontrol conditions or treadmill exercise (70% of max speed, 1 h/day, 5 days/week). At the end of the inter-vention, the tPVAT was removed and conditioned media was made. The cleaned aorta was attached to a forcetransducer to assess endothelium-dependent and independent dilation in the presence or absence of tPVAT-conditioned media. tPVAT gene …