Parkinson Disease Research

Parkison disease is a complex neurodegenerative disorder that affects the central nervous system (CNS) and peripheral nervous system (PNS). Our translational research program studies how the onset and progression of neuropathology affects important functions such as communication, swallow, and airway protection with the aim of developing better identification and treatment.

The hallmark pathology of PD, loss of dopamine, has guided therapy for decades; however, dopamine-centered treatments do not improve vocal communication, cognition, or affect. In fact, during the early stages of PD prior to dopamine loss, there is significant degeneration in the locus coeruleus, a brainstem region rich in norepinephrine. This region is vital to communicative cognitive behaviors, indicating the importance of norepinephrine in controlling communication and cognitive processes. This research will examine three different therapeutic approaches that modulate norepinephrine: exercise, drugs, and social interaction. The rationale is that modulating noradrenergic brain systems will improve PD-related communication deficits, as well as cognition and affect while monitoring unwanted side effects.Representative spectrograms of simple (left) and complex (right) ultrasonic vocalizations of one adult male rat in the control condition.

The pathology of Parkinson disease is complex and the pathogenesis underlying cranial sensorimotor behaviors, such as voice and swallowing deficits, are virtually unknown. Further, the onset of these deficits may occur in the prodrome. To address these issues genetic rat and mouse models of Parkinson diseases and test the onset and progression of vocalization, tongue use, chewing, functional swallowing, olfaction, forelimb use, gait, cognition, and memory dysfunction. Our primary goals are to relate these behavioral deficits to the complex neuropathology of PD in order to improve behavioral, pharmacologic and surgical interventions.Representative Spectrograms of frequency modulated calls from WT, Pink1-/- Non-Exercise and Pink-/- exercise groups. Intensity is coded by shade with warmer colors indicated higher intensity values. This image shows that the Pink-/- Non-Exercise group had lower call intensity in comparison to the Wild-type non exercise and Pink1-/- Exercise groups.

Recent evidence shows that Parkinson disease affects not only the central nervous system, but also autonomic function and peripheral nerves and muscles. Our research efforts are aimed at determining the timing and progression of pathology in peripheral nerves and muscles that affect communication and ingestive behaviors, such as oropharyngeal swallowing.Thyroarytenoid (TA) muscle processing. One TA muscle from each larynx was analyzed through ex vivo force measurements. The other TA muscle from each larynx was embedded in optimal cutting temperature compound (OCT) and sectioned for microscopic myofiber analyses including cross-sectional area (CSA), after which the remaining muscle was isolated from OCT and cartilage and was homogenized for myosin heavy chain isoform (MyHC) analysis. TA-V, vocalis division of the TA; TA-X, external division of the TA.