Parkinson Disease

Parkinson's disease is an incurable, progressive neurodegenerative brain disorder. Individuals living with Parkinson's disease often face considerable challenges in managing the progressive decline of their symptoms and maintaining their quality of life (Broadfoot et al., 2019). During the progression of PD, 75-90% of individuals will have a speech and voice disorder (National Center for Voice and Speech, 2019). The communication disorder most commonly associated with PD is hypokinetic dysarthria (HKD). Many individuals with PD may have significant difficulty communicating and participating effectively in a variety of speaking situations due to their communication deficits (Dykstra et al., 2015). Addressing an individuals perceived quality of communication and their perceived communication effectiveness should be an essential target during intervention due to the implications it has on the psychological well-being and prognosis for people with PD. Participants in this study were recruited from individuals previously diagnosed with Parkinson's disease attending the SPEAK OUT! & LOUD Crowd® program. The research questions included (1) Does the implementation of the SPEAK OUT! ® and the LOUD Crowd® program have a positive effect on participants’ perceived quality of communication (PQOC), and (2) Do these programs have a significant positive effect on participants perceived communicative effectiveness (PCE)? The Voice Handicap Index (VHI) and the Communicative Effectiveness Survey- Revised (CESR®) were utilized in this research study. The surveys were administered prior to the SPEAK OUT!® training and following the completion of this portion of the program. They were administered every 16 weeks while the participant was in the LOUD Crowd® training during the duration of this project. It was hypothesized that participants' PQOC related to their voice and their PCE will improve following the implementation of this program. Due to COVID-19 restrictions, results from this study only considered baseline scores and post-test 1 scores following the completion of the SPEAK OUT!® program. The results from this study support the hypothesis that the SPEAK OUT!® program has a positive effect on the participants’ PQOC.

The kynurenine pathway plays a critical role in regulating immunological homeostasis in the brain. Evidence supporting the hypothesis that kynurenine pathway dysfunction may exacerbate progression of neurodegenerative diseases like Parkinson’s is growing. First, we investigate the effects of Interferon-γ, Lipopolysaccharide, and Interleukin-4 on several key kynurenine pathway metabolites using high performance liquid chromatography. We found that Interferon-γ had significant effects on the extracellular concentration of kynurenine metabolites in astrocytes, microglia, and macrophage. GCSF gene therapy is previously demonstrated to exert neuroprotective effects on models of Parkinson’s and Alzheimer’s disease. Seven days after receiving GCSF gene therapy, A53T Parkinson’s mice were found to have increased levels of GCSF and tyrosine hydroxylase positive neurons. A concurrent increase in expression of the kynurenine pathway enzyme kynurenine aminotransferase 2 was observed. GCSF gene therapy may exhibit neuroprotective effects in a Parkinson’s disease mouse model by restoring this key kynurenine pathway enzyme.