Basic and Translational Research


Finding Effective Treatments For Inhaled Chlorine-Induced Injury Related Pain

Principal Investigator: Sadis Matalon, Ph.D.
Assessment of locomotion following exposure of animals to noxious or painful stimuli can offer significant insights into underlying mechanisms of injury and the effectiveness of various treatments. We developed a novel method to track the movement of mice in two dimensions using computer vision and neural network algorithms. By using this system we demonstrated that mice exposed to chlorine (Cl2 ) developed impaired locomotion and increased immobility for up to 9 hours post-exposure. Post-exposure administration of buprenorphine, a common analgesic agent, increased locomotion and decreased immobility times in Cl2 but not air-exposed mice, most likely by decreasing Cl2 induced pain. Currently we are assessing whether inhaled local anesthetics alone and as an adjunct to beta Iadrenoceptor agonist, are effective in reducing pain behaviors and in reducing morbidity and mortality following Cl2 exposure in mice.
Key collaborators: Timothy Ness, M.D., Ph.D.


Inflammation-Induced Opioidergic Antinocieption  
Principal Investigator: Alan Randich, Ph.D. (Adjunct Faculty)
Since retiring from Psychology, Dr. Randich (Professor Emeritus) has continued his collaborative research projects with Drs. Ness and Robbins in Anesthesiology, and has identified the activation of a descending modulatory system that can be activated by the induction of visceral inflammation. Not present in superficial (cutaneous) model systems, this system appears to suppress excessive expression of nociceptive responses evoked by deep tissue stimuli (joint, muscle, viscera) and involves an opioidergic mechanism as it is reversed by naloxone. This system appears to be deficient in chronically hypersensitive animals. Probing the molecular basis of this reactive system has utilized Western blot and ELISA analysis of endogenous opioid agonist and receptor expression. Most recently, a role for interactions between TRPA1 and opioid receptors is being examined in both behavioral and neurophysiological experiments.

 
Interaction of ENaC and CFTR channels in alveolar epithelial cells in vivo 
Principal Investigator: Sadis Matalon, Ph.D.
We are measuring ENaC single channel activity of alveolar type II cells by patching these cells in freshly prepared lung slices from wild-type, heterozygous (Cftr(+/-)), knockout (Cftr(-/-)), and ΔF508-expressing mice in situ. Our results indicate that ENaC activity is inversely correlated to predicted CFTR levels and that CFTR heterozygous and homozygous mice have higher levels of proteolytically processed ENaC fragments in their lungs. This is the first demonstration of functional ENaC-CFTR interactions in alveolar epithelial cells in situ.
Key collaborators: Jim Collawn, Ph.D.David M. Bedwell, Ph.D.


Mechanisms by which influenza infection decreases activity and expression of lung epithelial cells 
Principal Investigator: Sadis Matalon, Ph.D.
Results of current studies show that matrix protein 2 (M2), a transmembrane influenza protein which acts as a hydrogen ion channel and is essential for viral replication, inhibits the activity of amiloride sensitive epithelial ion channels (ENaC) and cystic fibrosis transmembrane conductance regulator (CFTR) by increasing the production of reactive intermediates and increasing secretory cell pH. These studies utilize state of the art biophysical techiques (measurement of single channel of ENaC an CFTR channels) as well as measurements of ion channel protein levels in the plasma membranes of Xenopus oocyts injected with ENaC and CFTR cRNAs, epithelial cells overexpressing ENaC and CFTR as well human cells with native ENaC and CFTR injected with wild type and mutant forms of M2. 
Key collaborators: James Noah, Ph.D. (SRI)Diana Lee Noah, Ph.D. (SRI)


Mechanisms of Chronic Pain in Women 
Principal Investigator: Ursula Wesselmann, M.D., Ph.D. 
Dr. Wesselmann has a long-standing interest in the neurobiological mechanisms of chronic pain syndromes in women. She is a clinical neurologist and experimental neuro-physiologist with sub-specialty training in pain management. Over the last 20 years NIH-funded studies in her translational research laboratory have focused on the common theme of (1) elucidating peripheral and central pain mechanisms via neurophysiological, neuroanatomical and psychophysical paradigms in health and disease, specifically in females and (2) phenotyping subgroups of patients with pain syndromes based on different pathophysiological mechanisms, with the goal of identifying novel treatment strategies for these different phenotypes based on the underlying pathophysiology. Her current research, in collaboration with Dr. P. Czakanski (Depts. of Anesthesiology and Obstetrics & Gynecology), focuses on neurophysiological, psychosocial and autonomic factors that contribute to the onset and maintenance of chronic urological (interstitial cystitis) and gynecological (vulvodynia) pain syndromes in women. A new area of research investigation is to determine the biological, psychological, and socio-cultural variables contributing to pain and pain-related disability in women treated for breast cancer. The long-term goal of her research program is to translate new discoveries into clinical practices that improve the ability to diagnose and treat women experiencing chronic pain.

 
Mechanisms of Stress-Induced Hyperalgesia 
Principal Investigator: Meredith Robbins, Ph.D. 
In NIH-funded studies Dr. Robbins, a Ph.D. trained in Psychology with postdoctoral training in neurophysiology, is leading investigations into the molecular and behavioral consequences of experimentally-induced stress using rodent models. She has identified that a previously ignored endogenous peptide family, urocortins, and their associated receptor, CRFR2, are pivotal to increases in visceral sensitivity that are induced by experimental stress. Using ablative techniques and molecular-cell biological endpoints (Western blot analysis, ELISA measure, immunohistochemistry) the up or down regulation of spinal neuropeptide content and receptor number in response to environmental stressors is being identified and parallel responses in visceral and somatic sensitivity models assessed. In collaborative studies with Ness, central nervous system mechanisms of this stress-induced hyperalgesia that involve the amygdala are being identified using a experiments that lead to either abolition (neuroablative procedures) or augmenting (intracerebral implantations) effects.


Mechanisms of Urologic-Gastroenterologic Pain
Principal Investigator: Timothy Ness, M.D., Ph.D.
In NIH-funded studies, truly translational studies related to urinary bladder and colorectal sensation are being performed by measuring psychophysical responses in humans and parallel studies in rodents. Dr. Ness with collaborators (Drs. Randich and Robbins) have determined that developmental mechanisms related to visceral hypersensitivity can be initiated by early-in-life inflammatory events that lead to altered neurophysiological processing as adults. These observations are now supported by epidemiological studies. The precise interplay between excitatory and inhibitory influences that exist at a spinal level are being dissected out using behavioral, neurophysiological (spinal dorsal horn, medullary and thalamic extracellular neuronal studies) and immunohistochemical (c-fos induction) studies in this programmatic line of research. Psychophysical studies have identified deficiencies in endogenous pain control systems related to counterirritation—similar deficits have been identified in preclinical experimental models.


Mitochondrial Bioenergetic Dysfunction and Chlorine Toxicity
Principal Investigator: Sadis Matalon, Ph.D.
Exposure to Cl2, released into the atmosphere during transportation and industrial accidents, as well as during acts of terrorism results in significant morbidity and mortality to both humans and animals. When inhaled, Cl2 first reacts with antioxidants in the lung epithelial lining fluid (ELF); when antioxidants are depleted, it forms relatively stable adducts with proteins, components of the extracellular matrix and unsaturated fatty acids which then proceed to prolong the toxicity of the initial Cl2 exposure and contribute to the long term pathology. We are testing the hypothesis that these secondary reactive species target the mitochondrion and decrease mitochondrial quality and cause bioenergetic dysfunction which delays tissue recovery and repair. Based upon these data we hypothesize that mitochondria are a critical target for Cl2 toxicity in lung epithelial cells and the combined strategy of preventing mitochondrial oxidative damage by mitochondrial targeted antioxidants (such as MitoQ) with enhancing mitophagy (by rapamycin and trehalose), will be beneficial in ameliorating Cl2 toxicity.
Key collaborators: Victor Darley-Usmar, Ph.D.; Jianhua Zhang, Ph.D.


Post Exposure Aerosolized Heparin Reduces Lung Injury in Chlorine Exposed Mice
Principal Investigator: Sadis Matalon, Ph.D.
In this study we are testing the hypothesis that exposure of mice to Cl2causes the intra-alveolar and systemic activation of the coagulation cascade that plays an important role in the development of lung injury. Native coagulation (NATEM) parameters such as blood clotting time and clot formation time as well as D-Dimers and thrombin-anti-thrombin complexes are measured in both plasma and Bronchoalveolar Lavage Fluid (BALF). 
Key collaborators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.

 
Quantitative Studies of Urinary Bladder Sensation

Principal Investigator: Timothy Ness, M.D.
In NIH-funded studies, truly translational studies related to urinary bladder and colorectal sensation are being performed by measuring psychophysical responses in humans and parallel studies in rodents. Dr. Ness with collaborators (Randich, Robbins) have  determined that developmental mechanisms related to visceral hypersensitivity can be initiated by early-in-life inflammatory events that lead to altered neurophysiological processing as adults. These observations are now supported by epidemiological studies. The precise interplay between excitatory and inhibitory influences that exist at a spinal level are being dissected out using behavioral, neurophysiological (spinal dorsal horn, medullary and thalamic extracellular neuronal studies) and immunohistochemical (c-fos induction) studies in this programmatic line of research. Psychophysical studies have identified deficiencies in endogenous pain control systems related to counterirritation—similar deficits have been identified in preclinical experimental models.


The Effects of Intranasal Oxytocin on Pain Sensitivity, Endogenous Pain Inhibition and Mood: A Randomized, Placebo-Controlled, Crossover Study
Principal Investigator: Burel Goodin, Ph.D.
Preliminary evidence implicates the neuroendocrine peptide, oxytocin, in the modulation of somatosensory transmission including nociception and pain perception. It has been suggested, albeit not tested, that OXT may indirectly influence the affective experience of pain through its documented anxiolytic effects and promotion of psychological well-being. This study aimed to: 1) obtain pilot outcome data pertaining to the impact of intranasal oxytocin on pain sensitivity and endogenous pain inhibition, and 2) examine the effects of intranasal oxytocin on pain-relevant mood factors (e.g., anxiety) and whether these factors are associated with pain sensitivity and endogenous pain inhibition.


The Role of Blunt Head Trauma in Nosocomial Lung Infections

Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
This project looks to understand to role of coagulopathy in lung infection after blunt head trauma. We are currently using a mouse model of head injury and have revealed that there is coagulopathy after head injury. We are currently studying the mechanisms of this coagulopathy, including the alpha-7 nicotinic receptor, and how this coagulopathy may lead to increased opportunity for nosocomial lung infection.
Key Collaborator: Patrick L. Bosarge, M.D.


The Role of the Glycocalyx after Trauma in Nosocomial Lung Infections

Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
This is a new collaboration in which we will look first at glycocalyx shedding after trauma/hemorrhage. From there, we will look into the mechanisms of how this shedding may lead to ARDS or increased risk of nosocomial infection.
Key Collaborator: Randall Dull, M.D., Ph.D. (University of Illinois College of Medicine at Chicago)  


The Role of IL-8 and phosphodiesterases in ARDS and Nosocomial Lung Infection
Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
After trauma, chemokines, including IL-8, are increased within the lung air spaces of patients. This leads to inhibition of beta-agonist-mediated alveolar fluid clearance. We are studying the role of PI3K and phosphodiesterases in this process and whether specific inhibitors of these proteins could restore the normal human response to beta-agonists in patients with ARDS.
Key Collaborators: Sadis Matalon, Ph.D.; Thomas C. Rich, Ph.D. (University of South Alabama)


The Role of N-WASP in Nosocomial Lung Infection
Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
IL-1beta and TGF-beta (mediators released during trauma and infection) lead to decreased lung epithelial barrier function and therefore increase a patient’s risk of nosocomial lung infection and ARDS. We have found that N-WASP is critically involved in this process and that its inhibition may be able to prevent these inhibitory processes and restore epithelial barrier function.
Key Collaborator: Qiang Ding, Ph.D.  


The Role of Vitamin E in Nosocomial Lung Infections

Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
We are studying the ability of Vitamin E to prevent bacterial injury to lung epithelial and endothelial cells in vitro. Additionally, we are determining the ability of Vitamin E to decrease mortality in a mouse model of nosocomial pneumonia.
Key Collaborator: Maret G. Traber, Ph.D. (Linus Pauling Institute at Oregon State University)


The Role of Whole Blood Resuscitation on Nosocomial Lung Infections

Principal Investigators: Jean-Francois Pittet, M.D.; Brant Wagener, M.D., Ph.D.
Resuscitation with banked blood induces immunomodulation and may increase a patient’s risk for ARDS and nosocomial pneumonia. We are studying these effects in a mouse model of trauma/hemorrhage and looking at mediators in banked blood that may be the cause of this phenomenon.
Key Collaborator: Rakesh Patel, Ph.D.