The Neuroscience Meet Up is a casual, friendly monthly event facilitating interdisciplinary conversations between University of Missouri researchers at all levels. Join us for food, beverages and socializing. Please forward this invite to anyone interested: students, faculty or staff within your groups.

For questions about this event and to be added to the monthly calendar invite, please reach out to Smita Saxena at smitasaxena@health.missouri.edu.

Speaker Bio

Preservation and/or improvement of respiratory and swallowing function and coordination following motor neuron loss

Our laboratory focuses on the central nervous system, and one research direction includes the control of breathing in models of motor neuron death. Breathing is essential to life and cannot cease for more than the briefest periods, or life will not continue. At the same time, breathing must be continuously adjusted throughout life to maintain homeostasis in response to physiological (for example exercise, pregnancy or high altitude) or pathological (for example disease or disorder) situations. One way the neural system controlling breathing maintains homeostasis is to express plasticity, which is defined as a persistent change in the neural control system based on a prior experience. A well-known model of respiratory plasticity is phrenic long-term facilitation (pLTF), a long-lasting increase in phrenic motor output elicited by acute exposure to intermittent hypoxia. Although, we know a great deal about the mechanism that underlies pLTF under normal circumstances, the mechanism that underlies pLTF and how it is affected by contributing factors (e.g., inflammation) in models of motor neuron death is not well understood. Determining the mechanism that underlies pLTF and how it can be enhanced in models of motor neuron death to preserve and/or improve breathing is one focus of the laboratory.

Another focus of the Nichols laboratory is to investigate the function and coordination of swallowing and breathing in models of motor neuron death in collaboration with the laboratory of Dr. Teresa Lever. Swallowing and breathing rely on shared upper airway structures that are damaged in many motor neuron diseases. These co-dependent functions are life-sustaining and require reciprocal roles of the tongue during swallowing. The impaired control and coordination of these opposing behaviors ultimately results in respiratory failure and death. In order to combat this impaired control, we are exploring the effects that tongue exercise and induction of plasticity have on upper airway function and coordination.

We utilize a multidisciplinary approach in the Nichols lab. These include: 1) novel pharmacological injections to induce models of motor neuron death; 2) whole animal plethysmography to measure respiration in unanesthetized animals; 3) videofluoroscopy swallow studies in conjunction with the Lever lab; 4) in vivo neurophysiology to measure spontaneous nerve output and nerve output in response to targeted drug delivery; 5) EMG to measure output in muscles responsible for breathing and swallowing function; 6) immunohistochemical localization of neurotransmitter receptors and proteins of interest on individual neurons, astrocytes and microglia; 7) PCR to measure gene expression; 8) TEM to study morphological changes in neurons, nerves, and muscles; and 9) MRI to quantify degenerative changes in the CNS. Using these techniques, we have developed novel models of motor neuron death that mimics aspects of neurodegenerative diseases related to ventilatory and swallowing functions. Further, using these models, we can study the mechanism that underlies plasticity in surviving motor neurons responsible for breathing and swallowing, and how plasticity can be enhanced following motor neuron death.