Physiology Commons^™

Increased Mitochondrial Superoxide In The Brain, But Not Periphery, Sensitizes Mice To Angiotensin Ii-Mediated Hypertension., Adam J. Case, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Angiotensin II (AngII) elicits the production of superoxide (O2(•-)) from mitochondria in numerous cell types within peripheral organs and in the brain suggesting a role for mitochondrial-produced O2(•-) in the pathogenesis of hypertension. However, it remains unclear if mitochondrial O2(•-) is causal in the development of AngII-induced hypertension, or if mitochondrial O2(•-) in the absence of elevated AngII is sufficient to increase blood pressure. Further, the tissue specific (i.e. central versus peripheral) redox regulation of AngII hypertension remains elusive. Herein, we hypothesized that increased mitochondrial O2(•-) in the absence of pro-hypertensive stimuli, such as AngII, elevates baseline systemic mean arterial …

Mitochondrial Superoxide Signaling Contributes To Norepinephrine-Mediated T-Lymphocyte Cytokine Profiles., Adam J. Case, Colton T. Roessner, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Norepinephrine (NE) produces multifaceted regulatory patterns in T-lymphocytes. Recently, we have shown that NE utilizes redox signaling as evidenced by increased superoxide (O2●-) causally linked to the observed changes in these cells; however, the source of this reactive oxygen species (ROS) remains elusive. Herein, we hypothesized that the source of increased O2●- in NE-stimulated T-lymphocytes is due to disruption of mitochondrial bioenergetics. To address this hypothesis, we utilized purified mouse splenic CD4+ and CD8+ T-lymphocytes stimulated with NE and assessed O2●- levels, mitochondrial metabolism, cellular proliferation, and cytokine profiles. We demonstrate that the increase in O2●- levels in response to …

Stable Engraftment Of Bifidobacterium Longum Ah1206 In The Human Gut Depends On Individualized Features Of The Resident Microbiome, María X. Maldonado-Gómez, Inés Martínez, Francesca Bottacini, Amy O’Callaghan, Marco Ventura, Douwe Van Sinderen, Benjamin Hillmann, Pajau Vangay, Dan Knights, Robert W. Hutkins, Jens Walter

Department of Food Science and Technology: Faculty Publications

Live bacteria (such as probiotics) have long been used to modulate gut microbiota and human physiology, but their colonization is mostly transient. Conceptual understanding of the ecological principles as they apply to exogenously introduced microbes in gut ecosystems is lacking. We find that, when orally administered to humans, Bifidobacterium longum AH1206 stably persists in the gut of 30% of individuals for at least 6 months without causing gastrointestinal symptoms or impacting the composition of the resident gut microbiota. AH1206 engraftment was associated with low abundance of resident B. longum and underrepresentation of specific carbohydrate utilization genes in the pre-treatment microbiome. …

Maternal Sleep Loss During Fetal Development Alters Offspring Endocrine Responses To Stress Throughout Life, Audrey Brown

Mahurin Honors College Capstone Experience/Thesis Projects

The hypothalamic-pituitary-adrenal (HPA) axis releases glucocorticoids, including corticosterone (CORT), in response to stress. CORT then negatively feeds back to inhibit its own production by binding to glucocorticoid receptors (GRs) in the hypothalamus and pituitary gland. The HPA axis is subject to “programming” by abnormal stimuli during early development, which may permanently alter how the HPA axis responds to stress. These altered responses have been linked to an increased risk for human psychiatric and metabolic disorders in later life, but the mechanism by which this happens is not fully understood. This study tests the hypothesis that changes to GR expression patterns …

Effect Of Taste Stimuli On Swallowing Function In Persons With Traumatic Injuries, Megan Asselin, Angela M. Dietsch

UCARE Research Products

Background

Swallowing disorders are prevalent and costly. As of now, there are limited therapeutic options available to treat them. Extant research in limited populations has suggested that swallowing mechanics can be improved by extremely sour liquids, but this has not been tested in traumatically injured populations. However, sour tastants are unpleasant, and more palatable taste mixtures have not been tested.

Methods

The quantitative data were extracted from an existing pool of de-identified video fluoroscopic swallowing studies (moving radiographs) obtained from traumatically injured young adults under another research protocol. Each participant completed swallows of custom-mixed plain, sour, and sweet-sour boluses. Positions …

Ablation Of Matrix Metalloproteinase-9 Prevents Cardiomyocytes Contractile Dysfunction In Diabetics., Priyanka Prathipati, Naira Metreveli, Shyam Sundar Nandi, Suresh C. Tyagi, Paras K. Mishra

Journal Articles: Cellular & Integrative Physiology

Elevated expression and activity of matrix metalloproteinase-9 (MMP9) and decreased contractility of cardiomyocytes are documented in diabetic hearts. However, it is unclear whether MMP is involved in the regulation of contractility of cardiomyocytes in diabetic hearts. In the present study, we tested the hypothesis that MMP9 regulates contractility of cardiomyocytes in diabetic hearts, and ablation of MMP9 prevents impaired contractility of cardiomyocytes in diabetic hearts. To determine the specific role of MMP9 in cardiomyocyte contractility, we used 12-14 week male WT (normoglycemic sibling of Akita), Akita, and Ins(2+∕-)/MMP9(-∕-) (DKO) mice. DKO mice were generated by cross-breeding male Ins2(+∕-) Akita (T1D) …

Glucocorticoid Receptor (Nr3c1) Variants Associate With The Muscle Strength And Size Response To Resistance Training., Garrett I Ash, Matthew A Kostek, Harold Lee, Theodore J Angelopoulos, Priscilla M Clarkson, Paul M Gordon, Niall M Moyna, Paul S Visich, Robert F Zoeller, Thomas B Price, Joseph M. Devaney, Heather Gordish-Dressman, Paul D Thompson, Eric P. Hoffman, Linda S Pescatello

Genomics and Precision Medicine Faculty Publications

Glucocorticoid receptor (NR3C1) polymorphisms associate with obesity, muscle strength, and cortisol sensitivity. We examined associations among four NR3C1 polymorphisms and the muscle response to resistance training (RT). European-American adults (n = 602, 23.8±0.4yr) completed a 12 week unilateral arm RT program. Maximum voluntary contraction (MVC) assessed isometric strength (kg) and MRI assessed biceps size (cm2) pre- and post-resistance training. Subjects were genotyped for NR3C1 -2722G>A, -1887G>A, -1017T>C, and +363A>G. Men carrying the -2722G allele gained less relative MVC (17.3±1.2vs33.5±6.1%) (p = 0.010) than AA homozygotes; men with -1887GG gained greater relative MVC than A allele carriers …

Low-Dose Aronia Melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity., Adam J. Case, D Agraz, Iman M. Ahmad, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Herbicides containing paraquat may contribute to the pathogenesis of neurodegenerative disorders such as Parkinson's disease. Paraquat induces reactive oxygen species-mediated apoptosis in neurons, which is a primary mechanism behind its toxicity. We sought to test the effectiveness of a commercially available polyphenol-rich Aronia melanocarpa (aronia berry) concentrate in the amelioration of paraquat-induced neurotoxicity. Considering the abundance of antioxidants in aronia berries, we hypothesized that aronia berry concentrate attenuates the paraquat-induced increase in reactive oxygen species and protects against paraquat-mediated neuronal cell death. Using a neuronal cell culture model, we observed that low doses of aronia berry concentrate protected against paraquat-mediated …

Success Stories And Emerging Themes In Conservation Physiology, Christine L. Madliger, Steven J. Cooke, Erica J. Crespi, Jennifer L. Funk, Kevin R. Hultine, Kathleen E. Hunt, Jason R. Rohr, Brent J. Sinclair, Cory D. Suski, Craig K. R. Willis, Oliver P. Love

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The potential benefits of physiology for conservation are well established and include greater specificity of management techniques, determination of cause–effect relationships, increased sensitivity of health and disturbance monitoring and greater capacity for predicting future change. While descriptions of the specific avenues in which conservation and physiology can be integrated are readily available and important to the continuing expansion of the discipline of ‘conservation physiology’, to date there has been no assessment of how the field has specifically contributed to conservation success. However, the goal of conservation physiology is to foster conservation solutions and it is therefore important to assess whether …

Angiotensin Ii-Induced Hypertension Is Attenuated By Overexpressing Copper/Zinc Superoxide Dismutase In The Brain Organum Vasculosum Of The Lamina Terminalis., John P. Collister, Heather Taylor-Smith, Donna Drebes, David Nahey, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Angiotensin II (AngII) can access the brain via circumventricular organs (CVOs), including the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), to modulate blood pressure. Previous studies have demonstrated a role for both the SFO and OVLT in the hypertensive response to chronic AngII, yet it is unclear which intracellular signaling pathways are involved in this response. Overexpression of copper/zinc superoxide dismutase (CuZnSOD) in the SFO has been shown to attenuate the chronic hypertensive effects of AngII. Presently, we tested the hypothesis that elevated levels of superoxide (O2 (∙-)) in the OVLT contribute to the hypertensive effects …

Low-Dose Aronia Melanocarpa Concentrate Attenuates Paraquat-Induced Neurotoxicity, Adam J. Case, Daniel Agraz, Iman M. Ahmad, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

No abstract provided.

Angiotensin Ii-Induced Hypertension Is Attenuated By Overexpressing Copper/Zinc Superoxide Dismutase In The Brain Organum Vasculosum Of The Lamina Terminalis., John P. Collister, Heather Taylor-Smith, Donna Drebes, David Nahey, Jun Tian, Matthew C. Zimmerman

Journal Articles: Cellular & Integrative Physiology

Angiotensin II (AngII) can access the brain via circumventricular organs (CVOs), including the subfornical organ (SFO) and organum vasculosum of the lamina terminalis (OVLT), to modulate blood pressure. Previous studies have demonstrated a role for both the SFO and OVLT in the hypertensive response to chronic AngII, yet it is unclear which intracellular signaling pathways are involved in this response. Overexpression of copper/zinc superoxide dismutase (CuZnSOD) in the SFO has been shown to attenuate the chronic hypertensive effects of AngII. Presently, we tested the hypothesis that elevated levels of superoxide (O2 (∙-)) in the OVLT contribute to the hypertensive effects …

Mitochondrial Function Assessed By 31p Mrs And Bold Mri In Non-Obese Type 2 Diabetic Rats, Yuchi Liu, Xunbai Mei, Jielei Li, Nicola Lai, Xin Yu

Electrical & Computer Engineering Faculty Publications

The study aims to characterize age-associated changes in skeletal muscle bioenergetics by evaluating the response to ischemia-reperfusion in the skeletal muscle of the Goto-Kakizaki (GK) rats, a rat model of non-obese type 2 diabetes (T2D). ³¹P magnetic resonance spectroscopy (MRS) and blood oxygen level-dependent (BOLD) MRI was performed on the hindlimb of young (12 weeks) and adult (20 weeks) GK and Wistar (control) rats. ³¹P-MRS and BOLD-MRI data were acquired continuously during an ischemia and reperfusion protocol to quantify changes in phosphate metabolites and muscle oxygenation. The time constant of phosphocreatine recovery, an index of mitochondrial oxidative capacity, …