Physiology Commons^™

Sensitivity Of Prescribing High-Intensity, Interval Training Using The Critical Power Concept, Robert W. Pettitt, Ashley M. Placek, Ida E. Clark, Nicholas A. Jamnick, Steven R. Murray

International Journal of Exercise Science

International Journal of Exercise Science 8(3): 202-212, 2015. The critical power (CP) concept enables the calculation of time to exhaustion (t_LIM) for a given power output above CP using the equation of t_LIM = W’/(power – CP), where W’ is the curvature constant, and CP is the asymptote for the power-t_LIM relationship. The CP concept offers great promise for prescribing high-intensity interval training (HIIT); however, knowledge on the concept’s sensitivity is lacking (i.e., how much of a difference in W’ expenditure is needed to evoke different metabolic responses). We tested if two …

Regulation Of Thyroid Hormone-Induced Development In Vivo By Thyroid Hormone Transporters And Cytosolic Binding Proteins, Jinyoung Choi, Christine L. Moskalik, Allison Ng, Stephen F. Matter, Daniel R. Buchholz

Publications & Research

Differential tissue sensitivity/responsivity to hormones can explain developmental asynchrony among hormone-dependent events despite equivalent exposure of each tissue to circulating hormone levels. A dramatic vertebrate example is during frog metamorphosis, where transformation of the hind limb, brain, intestine, liver, and tail are completely dependent on thyroid hormone (TH) but occurs asynchronously during development. TH transporters (THTs) and cytosolic TH binding proteins (CTHBPs) have been proposed to affect the timing of tissue transformation based on expression profiles and in vitro studies, but they have not been previously tested in vivo. We used a combination of expression pattern, relative expression level, …

Monitoring The Progression Of Spontaneous Articular Cartilage Healing With Infrared Spectroscopy, Megan P. O'Brien, Madhuri Penmatsa, Uday Palukuru, Paul West, Xu Yang, Mathias P. G. Bostrom, Theresa Freeman, Nancy Pleshko

Publications and Research

Objective. Evaluation of early compositional changes in healing articular cartilage is critical for understanding tissue repair and for therapeutic decision-making. Fourier transform infrared imaging spectroscopy (FT-IRIS) can be used to assess the molecular composition of harvested repair tissue. Furthermore, use of an infrared fiber-optic probe (IFOP) has the potential for translation to a clinical setting to provide molecular information in situ. In the current study, we determined the feasibility of IFOP assessment of cartilage repair tissue in a rabbit model, and assessed correlations with gold-standard histology.

Design. Bilateral osteochondral defects were generated in mature white New Zealand rabbits, and …

Lh-Independent Testosterone Secretion Is Mediated By The Interaction Between Gnrh2 And Its Receptor Within Porcine Testes, Amy T. Desaulniers, Rebecca A. Cederberg, Ginger A. Mills, J. Joe Ford, Clay A. Lents, Brett R. White

Department of Animal Science: Faculty Publications

Unlike classic gonadotropin-releasing hormone 1 (GNRH1), the second mammalian isoform (GNRH2) is an ineffective stimulant of gonadotropin release. Species that produce GNRH2 may not maintain a functional GNRH2 receptor (GNRHR2) due to coding errors. A full-length GNRHR2 gene has been identified in swine, but its role in reproduction requires further elucidation. Our objective was to examine the role of GNRH2 and GNRHR2 in testicular function of boars. We discovered that GNRH2 levels were higher in the testis than in the anterior pituitary gland or hypothalamus, corresponding to greater GNRHR2 abundance in the testis versus the anterior pituitary gland. Moreover, GNRH2 …

Serum Amyloid A Facilitates Early Lesion Development In Ldlr-/- Mice, Paulette A. Krishack, Clarissa V. Bhanvadia, John Lukens, Timothy J. Sontag, Maria C. De Beer, Godfrey S. Getz, Catherine A. Reardon

Physiology Faculty Publications

BACKGROUND: Atherosclerosis is a chronic inflammatory disorder, and several studies have demonstrated a positive association between plasma serum amyloid A (SAA) levels and cardiovascular disease risk. The aim of the study was to examine whether SAA has a role in atherogenesis, the underlying basis of most cardiovascular disease.

METHODS AND RESULTS: Mice globally deficient in acute-phase isoforms Saa1 and Saa2 (Saa^-/-) were crossed to Ldlr^-/- mice (Saa^-/-Ldlr^-/-). Saa^-/-Ldlr^-/- mice demonstrated a 31% reduction in lesional area in the ascending aorta but not in the aortic root or innominate …

Hydrophobic Surfactant Proteins Strongly Induce Negative Curvature, Mariya Chavarha, Ryan W. Loney, Shankar B. Rananavare, Stephen B. Hall

Chemistry Faculty Publications and Presentations

The hydrophobic surfactant proteins SP-B and SP-C greatly accelerate the adsorption of vesicles containing the surfactant lipids to form a film that lowers the surface tension of the air/water interface in the lungs. Pulmonary surfactant enters the interface by a process analogous to the fusion of two vesicles. As with fusion, several factors affect adsorption according to how they alter the curvature of lipid leaflets, suggesting that adsorption proceeds via a rate-limiting structure with negative curvature, in which the hydrophilic face of the phospholipid leaflets is concave. In the studies reported here, we tested whether the surfactant proteins might promote …

Editorial: Carotid Body: A New Target For Rescuing Neural Control Of Cardiorespiratory Balance In Disease., Rodrigo Del Rio, Rodrigo Iturriaga, Harold D. Schultz

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

Myocyte Contractility Can Be Maintained By Storing Cells With The Myosin Atpase Inhibitor 2,3 Butanedione Monoxime, Charles S. Chung, Charles Mechas, Kenneth S. Campbell

Physiology Faculty Publications

Isolated intact myocytes can be used to investigate contractile mechanisms and to screen new therapeutic compounds. These experiments typically require euthanizing an animal and isolating fresh cells each day or analyzing cultured myocytes, which quickly lose their rod-shaped morphology. Recent data suggest that the viability of canine myocytes can be prolonged using low temperature and N-benzyl-p-toluene sulfonamide (an inhibitor of skeletal myosin ATPase). We performed similar studies in rat myocytes in order to test whether the cardiac myosin ATPase inhibitors 2,3-Butanedione monoxime (BDM) and blebbistatin help to maintain cell-level function over multiple days. Myocytes were isolated from rats and separated …

Estrogen Receptor–Α In Medial Amygdala Neurons Regulates Body Weight, Pingwen Xu, Xuehong Cao, Yanlin He, Liangru Zhu, Yongjie Yang, Kenji Saito, Chunmei Wang, Xiaofeng Yan, Antentor Othrell Hinton Jr., Fang Zou, Hongfang Ding, Yan Xia, Chunling Yan, Gang Shu, San-Pin Wu, Bin Yang, Benjamin Feng, Deborah J. Clegg, Richard Demarchi, Sohaib A. Khan, Sophia Y. Tsai, Francesco J. Demayo, Qi Wu, Qingchun Tong, Yong Xu

Peer Reviewed Articles

Estrogen receptor–α (ERα) activity in the brain prevents obesity in both males and females. However, the ERα-expressing neural populations that regulate body weight remain to be fully elucidated. Here we showed that single-minded–1 (SIM1) neurons in the medial amygdala (MeA) express abundant levels of ERα. Specific deletion of the gene encoding ERα (Esr1) from SIM1 neurons, which are mostly within the MeA, caused hypoactivity and obesity in both male and female mice fed with regular chow, increased susceptibility to diet-induced obesity (DIO) in males but not in females, and blunted the body weight–lowering effects of a glucagon-like peptide-1–estrogen …

The Identification Of Novel Protein-Protein Interactions In Liver That Affect Glucagon Receptor Activity, Junfeng Han, Ming Zhang, Sean Froese, Feihan F. Dai, Mélanie Robitaille, Alpana Bhattacharjee, Xinyu Huang, Weiping Jia, Stéphane Angers, Michael B. Wheeler, Li Wei

Faculty Publications

Glucagon regulates glucose homeostasis by controlling glycogenolysis and gluconeogenesis in the liver. Exaggerated and dysregulated glucagon secretion can exacerbate hyperglycemia contributing to type 2 diabetes (T2D). Thus, it is important to understand how glucagon receptor (GCGR) activity and signaling is controlled in hepatocytes. To better understand this, we sought to identify proteins that interact with the GCGR to affect ligand-dependent receptor activation. A Flag-tagged human GCGR was recombinantly expressed in Chinese hamster ovary (CHO) cells, and GCGR complexes were isolated by affinity purification (AP). Complexes were then analyzed by mass spectrometry (MS), and protein-GCGR interactions were validated by co-immunoprecipitation (Co-IP) …

Iron As A Biomarker For Alzheimer’S Disease, Samual Barlow, Dr. Jonathan Wisco

Journal of Undergraduate Research

Alzheimer’s Disease (AD) is one of the highest causes of death in the United States. After the age of 65, the chance of getting Alzheimer’s doubles every five years. As the average lifespan of Americans increases, the importance of understanding AD and finding more efficient ways to treat it increases as well. The earlier AD is treated, the more effectively we are able to treat it. Non-heme iron (Fe) has been shown to spatially correlate with Abeta. Since Fe causes a signal dropout in susceptibility-weighted Magnetic Resonance Imaging (MRI), this imaging modality could possibly be used as a way to …

Cyclic Rhamnosylated Elongation Factor P Establishes Antibiotic Resistance In Pseudomonas Aeruginosa, Andrei Rajkovic, Sarah Erickson, Anne Witzky, Owen E. Branson, Jin Seo, Philip R. Gafken, Michael A. Frietas, Julian P. Whitelegge, Kym F. Faull, William Wiley Navarre, Andrew J. Darwin, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Elongation factor P (EF-P) is a ubiquitous bacterial protein that is required for the synthesis of poly-proline motifs during translation. In Escherichia coli and Salmonella enterica, the posttranslational β-lysylation of Lys34 by the PoxA protein is critical for EF-P activity. PoxA is absent from many bacterial species such as Pseudomonas aeruginosa, prompting a search for alternative EF-P posttranslation modification pathways. Structural analyses of P. aeruginosa EF-P revealed the attachment of a single cyclic rhamnose moiety to an Arg residue at a position equivalent to that at which β-Lys is attached to E. coli EF-P. Analysis of the genomes …

Anatomical Variation Of The Porcine Recurrent Laryngeal Nerve, Marc Christensen, Dr. Jonathan Wisco

Journal of Undergraduate Research

Selective reinnervation of the posterior cricoarytenoid muscle (PCA), accomplished by anastomosis of a transected recurrent laryngeal nerve (RLN) with the phrenic nerve, is the best treatment for vocal cord paralysis and RLN compromise. However, anatomical variation of the RLN in human patients contributes to the likelihood of post-operative complications such as laryngeal synkinesis. The purpose of this study, Anatomical Variation of the Porcine Recurrent Laryngeal Nerve, is to establish a clear and detailed understanding of RLN branching patterns in pigs, the animal model most similar to humans in regards to laryngeal anatomy, to determine nerve branches that are best …

The Effects Of Arginine Vasopressin On Maternal Behavior And Aggression In Peromyscus Californicus Mothers, Nathaniel Ng

Honors Projects

Research studies since the 1950s have shown that a chemical within the brain called arginine vasopressin (AVP) is associated with the modulation of many different social behaviors in mammals. Some of these behaviors are related to parenting, such as parental care initiation, aggression, social recognition, depression and anxiety. Understanding the physiology behind AVP regulation could allow for the creation of new therapies for treating human social disorders, such as using an AVP receptor antagonist to attenuate anxiety. This project examines how neural injections of AVP and an AVP receptor antagonist affect both maternal care and aggression in female Peromyscus californicus …

Orexin Receptor Activation Generates Gamma Band Input To Cholinergic And Serotonergic Arousal System Neurons And Drives An Intrinsic Ca(2+)-Dependent Resonance In Ldt And Ppt Cholinergic Neurons, Masaru Ishibashi, Iryna Gumenchuk, Bryan Kang, Catherine Steger, Elizabeth Lynn, Nancy Molina, Leonard M. Eisenberg, Christopher S. Leonard

NYMC Faculty Publications

A hallmark of the waking state is a shift in EEG power to higher frequencies with epochs of synchronized intracortical gamma activity (30-60 Hz) - a process associated with high-level cognitive functions. The ascending arousal system, including cholinergic laterodorsal (LDT) and pedunculopontine (PPT) tegmental neurons and serotonergic dorsal raphe (DR) neurons, promotes this state. Recently, this system has been proposed as a gamma wave generator, in part, because some neurons produce high-threshold, Ca(2+)-dependent oscillations at gamma frequencies. However, it is not known whether arousal-related inputs to these neurons generate such oscillations, or whether such oscillations are ever transmitted to neuronal …

Differential Receptors For Advanced Glycation End-Products (Rage) Expression In Preeclampsia, Intrauterine Growth Restriction And Gestational Diabetes, Kristen Lena Alexander

Theses and Dissertations

Preeclampsia (PE), intrauterine growth restriction (IUGR) and gestational diabetes (GDM) increase the risk of maternal and fetal morbidity and mortality. The roles of Advanced Glycation End-products (AGEs) are already well documented concerning inflammation, hypoxia and oxidative stress. AGEs bind to its receptor, Receptor for Advanced Glycation End-products (RAGE), and activate an inflammatory pathway. This pathway alters the efficacy of invasive trophoblast cells and in the placenta and can result in placental dysfunction. We hypothesized that the placental dysfunction found in PE, IUGR, and GDM resulted from an over activation of the RAGE-mediated inflammatory pathway. Using human placental samples, we found …

The Effects Of Inhibiting Wnt Secretion And Activity On Cranial And Neural Development, Julie Louise Hulet

Theses and Dissertations

Wnt signaling has been shown to have several roles in the development of sensory neurons, particularly in the ophthalmic portion of the trigeminal nerve. Many of these studies have relied on the conclusion that Wnt is necessary but not sufficient for the induction and maintenance of the neural precursor cells that develop in the ophthalmic placode. Wnt had been inhibited in the ophthalmic placode using a dominant negative t-cell factor (TCF) and resulted in the loss of Pax3 expression (indicative of undifferentiated placode cells) in all targeted cells, suggesting a loss of specification/commitment of these cells to the sensory neuron …

Cigarette Smoke Increases Cardiomyocyte Ceramide Accumulation And Inhibits Mitochondrial Respiration, Trevor Stanley Tippetts

Theses and Dissertations

Cigarette smoking is a common and lethal worldwide habit, with considerable mortality stemming from its deleterious effects on heart function. While current theories posit altered blood lipids and fibrinogen metabolism as likely mediators, none have explored the role of the sphingolipid ceramide in exacerbating heart function with smoke exposure. Ceramide production is a consequence of cigarette smoke in the lung, and considering ceramide's harmful effects on mitochondrial function, we sought to elucidate the role of ceramide in mediating smoke-induced altered heart mitochondrial respiration. Lung cells were exposed to cigarette smoke extract and heart cells were exposed to the lung-cell conditioned …

Hmgb1 And Ceramides: Potential Mediators Of Cigarette Smoke-Induced Metabolic Dysfunction, Mikayla Orton Thatcher

Theses and Dissertations

While cigarette smoking is a common-knowledge way to stay lean, it has long been known as a risk factor for diabetes and obesity. Here we establish that smoking causes fat gain and metabolic disruption in mice, effects which are exacerbated by a high-fat, high-sugar diet. We found that smoke exposure increases levels of ceramide—the lipid responsible for diet-induced insulin resistance—and that blocking ceramide production with the pharmacological inhibitor myriocin restored insulin sensitivity, stopped weight gain, and rescued mitochondrial respiration in vivo and in vitro.We also sought to assess the impact of the RAGE ligand HMGB1 on skeletal muscle metabolism. We …

The Caffeine Dose Response In Habitual Consumers Performing A Maximal Anaerobic Test, N T. Smith, K J. Ogden, A B. Mininger, J L. Haak, H S. Kieffer Facsm

International Journal of Exercise Science: Conference Proceedings

Please view abstract in the attached PDF file

Β-Alanine Supplementation Has No Effect On Rowing Performance In College Age Athletes, B J. Chrisfield, T D. Stutzman, Z Schutte, I Starr, A B. Porto, H S. Kieffer Facsm

International Journal of Exercise Science: Conference Proceedings

Please view abstract in the attached PDF file.

Mapping The Trigeminal Nerve, Kinnison Edmunds, Dr. Jonathan Wisco

Journal of Undergraduate Research

The goal of my project was to create a data-driven, three-dimensional map of the human trigeminal nerve from the trigeminal ganglion to the ends of its major pathways throughout the face and head. The purpose was to test conventional wisdom regarding the pathways of the trigeminal nerve and expose any inconsistencies between artistic representations and a data-driven mapping of the nerve. It was my hypothesis that by comparing my completed nerve map to the currently accepted anatomy literature, I will be able to challenge existing discrepancies and improve the validity of current anatomical representations.

Microarchitectural Analysis Of The Ulnar Collateral Ligament To Inform Its Reconstruction, Jakob Gamboa, Dr. Jonathan Wisco

Journal of Undergraduate Research

Ligaments are specialized connective tissues that stabilize the different synovial joints found in the body. Ligaments consist of fibroblast cells surrounded by a framework of dense fibrous bands of collagen, which anchor to bones to provide support and elasticity. Their varying biomechanical functions in different locations of the body require diversity in matrix composition, shape, density, and arrangement to adapt to the complex functions they perform. These characteristics may even vary within different regions of the same ligament. Damage to ligaments compromises integrity and movement of the joint and can lead to serious complications.

Customizing 3d Models From Mri Data: Creating Educational Anatomy Models Of Neurologic Disease, Brett Gardiner, Dr. Jon Wisco

Journal of Undergraduate Research

Neuroanatomy lab specimens are limited to cadaver availability and inconsistently demonstrate variations confronted in pathology. Using rapid prototyping (RP) technology to create 3D models from segmented MRI data offers distinct benefits to medical education. An efficient and replicable procedure for customizing these models can be developed to provide unique visual experiences for students and offer additional perspectives of brain models from real data.

Macrophage Migration Inhibitory Factor Mediates Par-Induced Bladder Pain., Dimitrios E. Kouzoukas, Katherine L. Meyer-Siegler, Fei Ma, Karin N. Westlund, David E. Hunt, Pedro L. Vera

Physiology Faculty Publications

INTRODUCTION: Macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine, is constitutively expressed in urothelial cells that also express protease-activated receptors (PAR). Urothelial PAR1 receptors were shown to mediate bladder inflammation. We showed that PAR1 and PAR4 activator, thrombin, also mediates urothelial MIF release. We hypothesized that stimulation of urothelial PAR1 or PAR4 receptors elicits release of urothelial MIF that acts on MIF receptors in the urothelium to mediate bladder inflammation and pain. Thus, we examined the effect of activation of specific bladder PAR receptors on MIF release, bladder pain, micturition and histological changes.

METHODS: MIF release was measured …

Immunolocalization Of G Protein-Coupled Estrogen Receptor In The Rat Epididymis, Griselle B. Martinez-Traverso, Christopher Pearl

Peer Reviewed Articles

Background

Estrogen plays an important role in male reproduction, and males lacking estrogen signaling in the reproductive tissues are infertile. Estrogen signaling is mediated via two nuclear receptors, ERα and ERβ, but it was recently found that a G protein-coupled estrogen receptor (GPER) is present in the testis. It is believed that GPER is a membrane form of the estrogen receptor and mediates non-classical estrogen signaling. However, the cellular localization of GPER in the epididymis is unknown. Therefore, the objective of this study was to determine the cellular and regional expression of GPER in the rat epididymis.

Findings

To localize …

Investigating The Effect Of Ethanol On Exocytosis In Vitro, Brady Hunt, Dixon Woodbury

Journal of Undergraduate Research

My research focus has been to investigate how ethanol’s pharmacological effects could be tied to it’s interactions with a key component of all cellular membranes, lipid bilayers.

Ventral Tegmental Area Dopamine And Gaba Neurons: Physiological Properties And Expression Of Mrna For Endocannabinoid Biosynthetic Enzymes And Type I Metabotropic Glutamate Receptors, Zachary Hopkins, Jeffrey G. Edwards

Journal of Undergraduate Research

The ventral tegmental area or VTA is considered to be one of the foremost centers involved in motivation and reward processing in the brain [1]. This area is also heavily implicated in addiction. However, little is known in regards to the exact cell types and subtypes found there, or the types of signaling that occur. We were interested in investigating the possibility of retrograde signaling among the two predominant cell groups in the VTA: GABA and dopamine neurons. Both cell types can be acted on by drugs of abuse, either to directly affect DA release or indirectly through GABA cells …

Novel Comet Assay Identifies Preliminary Dna Damage Prior To Cell Apoptosis In Mouse Model Of Rage Over-Expression, Steven Knapp, Paul Reynolds

Journal of Undergraduate Research

The goal of this project was to characterize the predisposing susceptibility of mice that overexpress receptors for advanced gylcation end products (RAGE) to apoptosis (cell death) and autophagy. Work has already been done to characterize this mouse model as pro-apoptotic; this new project will allow us to identify powerful markers that track DNA damage prior to cell death. RAGE is found in the lungs and aids in the transitioning of cell types (Reynolds P et Al., 2011). The expression of RAGE increases during instances of disease including COPD, diabetes, and lung cancer (Celli BR et Al., 2004, Wu L et …

3d Mapping Of Cardiac Nerves For Improved Cardiac Ablation Procedures In The Treatment Of Cardiac Arrhythmia, Adam Jorgensen, Jonathan J. Wisco

Journal of Undergraduate Research

Arrhythmia is a serious heart condition that affects 14 million people in the United Statesⁱ, and is characterized by irregular frequency of atrial and ventricular beats.ⁱⁱ The most serious effects of arrhythmia include sudden cardiac arrest and stroke.ⁱⁱⁱ About 383,000 cases of cardiac arrest are recorded annually in the United States alone.^iv In a report complied in 2011 by the World Health Organization, stroke has the second highest death rate of any disease worldwide, ending the lives of 6.1 million people annually.^v