Hypoxic-ischemic encephalopathy (HIE) is a leading cause of neonatal morbidity and mortality worldwide. The ferret provides a highly translational model to investigate HIE; the gyrified ferret brain has a similar grey-to-white matter ratio to humans, allowing for better assessment of white matter injury and impairment of cortical development compared to rodents. Our previous work has suggested that ferret brains also show greater resilience to hypoxia-ischemia (HI) than rats. Ferrets tolerate exposure to much longer and more significant HI, and 100-fold larger doses of inflammatory stimuli, than rats do. We seek to identify signatures of the ferret's protective mechanisms by comparing differentially regulated genetic pathways in the ferret versus the rat when exposed to identical insults. Whole-hemisphere organotypic brain slices were obtained from term-equivalent ferrets and rats and cultured for 72 hours. Slices were randomly assigned to control or oxygen-glucose deprivation (OGD), an in-vitro model of HIE. Cytotoxicity was assessed by lactate dehydrogenase (LDH) release, while global transcriptomics were analyzed via a 770-gene digital transcriptomics panel. Preliminary results show significantly lower LDH release in ferrets compared to rats, reaffirming the ferrets' resilience to OGD. We identified 90 differentially expressed genes in ferrets following OGD, and 11 genes in the rat. Ferrets upregulated CCL2 and LGALS, genes associated with inflammatory responses, and downregulated ADRB1 and NOS2, suggesting reduced oxidative stress. Rats downregulated KIR3DL1/2 and TGM1, which suppress natural killer cells and form the cell envelope, respectively. The experiment will be repeated with double the sample size and region-specific analysis of gene regulation. We hypothesize the ferret will display lower injury markers globally, which will be associated with regional differences in gene expression compared to the rat. We hope this will enable us to identify potential treatment targets for infants with HIE that can increase resilience and repair after injury. 

The axon initial segment (AIS) plays a crucial role in maintaining neuronal excitability and action potential initiation. It is structurally and functionally plastic, adapting to pathological conditions such as traumatic brain injury (TBI). While microglia, the resident immune cells of the central nervous system, are known to respond to injury and influence neuronal function, their interactions with the AIS remain underexplored. This study aims to investigate whether microglia associate with and alter the AIS before and after TBI, contributing to potential changes in excitability. Using a transgenic mouse model with GFP-labeled microglia, brain tissue is stained for neurons (Nissl), microglia (GFP), and the AIS (Ankyrin G) followed by confocal microscopy to obtain high-resolution images to visualize microglial interactions with the AIS. Image J is utilized to quantify AIS length, fluorescence intensity, and microglial proximity. I hypothesize that TBI induces structural changes in the AIS, including shortening or fragmentation, and that microglial interaction may play a role in these alterations. Preliminary data suggest an increased microglial presence near the AIS after injury, potentially indicating a role in either AIS disruption or repair. By identifying how microglia interact with the AIS, this research contributes to our understanding of neuroinflammatory responses following TBI. These findings may have implications for therapeutic strategies aimed at preserving neuronal function after injury. Further studies will explore whether microglia mediate AIS remodeling through direct contact or secreted factors, offering insights into potential interventions for TBI-related neurological dysfunction.

The glymphatic system is a brain-wide network of perivascular spaces that facilitates waste clearance by exchanging cerebrospinal fluid and interstitial fluid, promoting the clearance of solutes like amyloid β and tau from the brain. Impairment of the glymphatic system has been demonstrated in models of traumatic brain injury (TBI), which has emerged as a risk factor for neurodegenerative conditions like Alzheimer’s disease. These findings suggest that glymphatic impairment may contribute to the development of post-traumatic neurodegenerative conditions, highlighting the potential for therapeutic intervention. Post-TBI sleep disruption, headaches, cognitive deficits, and the brain's subsequent vulnerability to downstream neurodegeneration is a particular concern among veteran and athlete populations. Prazosin, an alpha-1 adrenergic receptor antagonist, has been used clinically in these groups to treat trauma-induced nightmares, where it has been shown to alleviate sleep disruption. However, little is known about its impact on the glymphatic system which is most active during sleep. Here, we hypothesized that glymphatic function is enhanced by blockade of central adrenergic tone, and that this modulation would improve deficits observed in mild blast and impact TBI models. To evaluate the effect of prazosin on glymphatic function in a murine model, we assessed glymphatic function in sham, blast TBI, and impact TBI mice following a 28-day treatment with prazosin. Post-injury behavioral tests were conducted to evaluate cognitive impairments across treatment groups. Using an intracisternal co-injection of infrared and conventional fixable fluorescent tracer, CSF distribution was evaluated through a validated in vivo dynamic imaging technique and paired with whole-slice fluorescent imaging. Our findings so far suggest enhancement of glymphatic function in sham-TBI prazosin treated groups compared to the control. Continued study may better elucidate the mechanisms that underlie post-TBI neurodegeneration, and provide insight into potential targets for treating neuropathological conditions linked to glymphatic system impairment.

Hypoxic Ischemic Encephalopathy (HIE) is a brain injury caused by a lack of oxygen and blood flow in the peripartum period. Cardiac dysfunction occurs in up to 80% of infants with HIE and is associated with worse neurodevelopmental outcomes. The current standard of care for HIE is whole body therapeutic hypothermia (TH). The expected physiologic response to TH is a decrease in cardiac output by 10%, and heartrate (HR) by 10bpm, per 1-degree Celsius decrease in body temperature. However, neonates with cardiac dysfunction tend to have normal or elevated HR to compensate for decreased cardiac output. Therefore, normal or elevated HR during TH may indicate compromised cardiac function. We hypothesize that in neonates with HIE, HR trends during TH reflect cardiac function, and a sustained HR above 100bpm is indicative of cardiac dysfunction. Using echocardiograms performed within the first 2 days after birth in babies with HIE treated with TH at the Seattle Children's neonatal intensive care unit (NICU; n=19), we categorized neonates by cardiac function: normal, right ventricular (RV) dysfunction, and RV plus left ventricular (LV) dysfunction. We then extracted continuous HR data and compared median HR during TH across groups using linear regression during specific periods: 12-24h, 24-36h, and 36-48h after birth. Results showed that infants with RV+LV dysfunction had a higher HR than those with RV dysfunction only or normal function. Across all time periods, infants with any kind of cardiac dysfunction had an average HR above 100bpm, while those without dysfunction had average HRs less than 100bpm. Therefore, it appears that HR can be utilized as a proxy for cardiac dysfunction in neonates with HIE. Utilizing HR as screening biomarker for cardiac dysfunction may allow improve optimal resource utilization of echocardiograms as well as real-time, cost-effective monitoring and targeted treatment initiation. 

Amyotrophic lateral sclerosis (ALS) is a progressive disease affecting 5000 people currently in the United States that is due to the degeneration of motor neurons, leading to muscle weakness, paralysis, respiratory failure, and ultimately death. To date, there has been extensive research investigating the underlying cause of the neurodegeneration that occurs in ALS, as well as attempts at targeted therapeutic interventions. CNM-Au8 is an investigational drug employing active gold (Au) nanocrystals designed to support neuronal survival by enhancing cellular energy production and reducing oxidative stress. The results of two randomized controlled phase 2 studies, the Healey Multiplatform Study and RESCUE-ALS, have suggested possible benefits from this therapy in both delaying disease progression, stabilizing respiratory function, and improving survival. The University of Washington (UW) is also a site for the Second Intermediate Expanded Access Protocol (EAP), allowing patients ineligible for the trials to receive the medication. The EAP follows an open-label, multi-center design, with all participants receiving daily oral doses of CNM-Au8. Participants undergo regular assessments every 12 weeks in person or via remote telehealth visits, allowing flexibility based on disease progression and external factors such as COVID-19 infection. The study tracks disease progression using measures such as the ALS Functional Rating Scale-Revised (ALSFRS-R) and slow vital capacity (SVC). ALSFRS-R is a questionnaire that evaluates a patient’s ability to perform daily activities, including speech, swallowing, mobility, and breathing. SVC is a measure of respiratory function crucial in monitoring ALS progression.