Molecular and Cellular Determinants of the Exercise Pressor Reflex in CHF


Principal Investigator: Irving H Zucker
Abstract: DESCRIPTION (provided by applicant): Chronic heart failure (CHF) is one of the leading causes of death in the U.S. A hallmark of CHF patients is elevated sympatho-excitation and exercise intolerance during physical activity. Even during moderate exercise, extreme activation of the sympathetic nervous system is often seen causing an exaggerated pressor response and hyperventilation, which potentially increases cardiovascular risk during physical activity in these patients. Existing evidence indicates that the exaggerated sympatho-excitation during exercise is directly related to increased contribution of the exercise pressor reflex (EPR). However, the molecular and cellular mechanisms underlying the increased EPR in CHF remain to be determined. Due to underperfused areas of skeletal muscle in CHF, release of reactive oxygen species and inflammation may activate the mitogen-activated protein kinase (MAPK) pathways in muscle afferent neurons. We hypothesize that chronic oxidative stress in muscle afferent terminals initiate activation of the MAPK signaling pathway in muscle afferent neurons in CHF. This activation, in turn, increases the afferent input of the EPR by affecting afferent neuronal excitability. At the cellular level, we hypothesize that enhanced voltage-gated sodium channel (Nav) activity in muscle afferent neurons (DRG's) of CHF rats contributes to the enhanced afferent neuronal excitability and the EPR. Since exercise training (ExT) prevents the exaggerated EPR in a myocardial infarction rat model we propose that ExT prevents the exaggerated EPR, in part, by inhibition of excessive activation of the MAPK pathway. We will use highly integrative techniques including molecular (real-time PCR, single cell real-time PCR, western blot, immunofluorescence, and in vivo gene transfer), cellular (patch clamp) and whole animal experiments (measuring EPR function, single afferent recording) to test these hypotheses. We believe that the proposed research will address important functional and mechanistic issues that directly relate to the quality of life in patients with CHF. Furthermore, w believe that these data will uncover new targets for therapy in CHF.
Funding Period: 2013-08-01 - 2017-07-31
more information: NIH RePORT

Detail Information

Research Grants30

  1. Interactive Signaling Modules in Vascular Inflammation
    Linda H Shapiro; Fiscal Year: 2013
    ..abstract_text> ..
  2. Discovery and Development of Therapeutic Genes for CHF
    H Kirk Hammond; Fiscal Year: 2013
    ..Four Cores will support the Program: Digital Imaging (Dr. Farquhar);Vector Production (Dr. Miyanohara);Translational Systems (Dr. Hammond) and Clinical &Administrative (Dr. Hammond). ..
  3. Role of Sphingolipids in the Pathobiology of Lung Injury
    Viswanathan Natarajan; Fiscal Year: 2013
    ..Together, this PPG addresses critical needs (insights, biomarkers, therapies) in ALI and RILI facilitating development of pharmacogenomic assays and SIP-based therapies for inflammatory lung injury. ..
    Costantino Iadecola; Fiscal Year: 2013
    ..Thus, the collective scientific outcome of the Program is anticipated to be greater than the sum of its individual components. ..
  5. Diverse Roles of Reactive Oxygen Species and Inflammation in Vascular Disease
    Kathy K Griendling; Fiscal Year: 2013
    ..Ultimately, this research may establish new unifying concepts linking conditions that alter vascular oxidant stress and inflammation to the molecular processes underlying vasculopathies. (End of Abstract) ..
  6. Neuro-Circulatory Function in Chronic Heart Failure
    Irving H Zucker; Fiscal Year: 2013
    ..The role of exercise training in modulating ROS generation and antioxidant enzymes in animals with CHF will also be investigated in this project. ..
  7. Host Factors in Regulation of Inflammatory and Fibroproliferative Lung Disease
    PAUL WESLEY NOBLE; Fiscal Year: 2013
    ..Each of these projects shares the common theme that interactions of host factors regulates inflammatory and fibrotic lung diseases. ..
  8. Rebuilding the Failing Heart
    Piero Anversa; Fiscal Year: 2013
    ..abstract_text> ..
  9. Lentiviral Gene Therapy for Sickle Cell Disease and Immunodeficiency Disorders
    Brian P Sorrentino; Fiscal Year: 2013
    ..abstract_text> ..
  10. Prevalence and Impact of Frailty among Dialysis Patients
    Kirsten L Johansen; Fiscal Year: 2013
    ..abstract_text> ..
  11. Center for Integrative Neuroscience
    Michael A Webster; Fiscal Year: 2013
    ..abstract_text> ..
    R John Solaro; Fiscal Year: 2013
    ..Studies proposed here offer the potential for novel diagnostic procedures early in the progression of the disorders, and targets for novel therapies. (End of Abstract) ..
    DONAL S O'LEARY; Fiscal Year: 2013
    ..These longitudinally designed experiments we feel will provide compelling new information on the altered mechanisms of cardiovascular control during exercise in heart failure. ..
  14. Molecular receptors on Group III-IV sensory neurons detecting muscle metabolites
    Alan R Light; Fiscal Year: 2013
  15. Mechanisms of Health Effects of Exercise in Children
    Dan M Cooper; Fiscal Year: 2013
    ..Collectively, the PPG will promote novel preventive and adjunctive exercise therapies in children with chronic inflammation- therapies grounded in a firm understanding of biological mechanisms. ..
  16. Signaling Processes Underlying Cardiovascular Function
    Jeffrey Robbins; Fiscal Year: 2013
    ..These projects are supported by 3 Cores: Core A: The Administrative Core;Core B: The Physiology Core and Core C: The Imaging-Cell Culture Core. (End of Abstract) ..
    Christopher S Wilcox; Fiscal Year: 2013
    ..These are supported by the Administrative, Animal and Bioanalytical Cores. ..
  18. Restoring Mycocardial Healing
    MARK ALAN SUSSMAN; Fiscal Year: 2013
    ..The goal of this program will be to delineate these deleterious signaling mechanisms and determine how they can be overcome to restore endogenous cellular repair processes that heal the damaged heart. ..
  19. Mechanisms of Atherogenesis in Insulin Resistance
    IRA A TABAS; Fiscal Year: 2013
    ..End of Abstract) ..
  20. Muscle Afferent Feedback Effects in Patients with Heart Failure
    Markus Amann; Fiscal Year: 2013
    ..Furthermore, our experiments will identify potential molecular targets for therapeutic interventions with the overall purpose to improve the quality of life in patients with HF. ..
  21. Excitability of afferents evoking the exercise pressor reflex
    Victor Ruiz-Velasco; Fiscal Year: 2013
    ..Likewise, in muscles, whose arteries are narrowed by disease, exercise can cause excessive stimulation of the sensory nerves that reflexively activate the sympathetic nervous system muscle pain (i.e., claudication). ..
  22. Role of Thromboxane in the Exercise Pressor Reflex in Peripheral Artery Disease
    ANNA KATHERINE LEAL; Fiscal Year: 2013
    ..These studies may lead to novel treatments that could potentially increase walking tolerance in individuals suffering from peripheral artery disease and reduce the risks and pain associated with physical activity. ..
    David Ginsburg; Fiscal Year: 2013
    ..This Project will identify key genes in this system that should provide valuable new diagnostic tools as well as suggest novel approaches to treatment. ..
  24. Neurohumoral control of veins in hypertension
    Gregory D Fink; Fiscal Year: 2013
    ..This project tests the idea that altered structure or function of veins also may cause hypertension, and that it may be possible to treat hypertension using drugs that affect veins. ..
  25. Autonomic and Antihypertensive Actions of Neuronal CGRP/RAMP1 Receptors
    Mark W Chapleau; Fiscal Year: 2013
    ..Inhibition of Ang II-mediated effects by activation of CGRP/RAMP1 receptors has widespread implications in hypertension and heart failure. ..
    David M Pollock; Fiscal Year: 2013
    ..In particular, this Program will investigate a full range of mechanisms that control ET-1 release and receptor specific actions in order to provide clinically relevant information. ..
    John E Hall; Fiscal Year: 2013
    ..End of Abstract) ..