Neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease are characterized by neuronal aggregation of alpha synuclein protein and other key biomarkers. Current biomarker assays rely on cerebrospinal fluid or plasma, which require invasive collection. Urine offers a non-invasive alternative; however, neuronal extracellular vesicles (nEVs) in urine are present at low concentrations and remain underexplored. nEVs transport materials between neurons, and, for that reason, they contain aggregated alpha synuclein and other important biomarkers in patients with neurodegenerative diseases. This project focuses on developing a protocol to isolate and characterize nEVs from urine samples using filtration and magnetic bead-based methods. Characterization to ensure EV isolation and biomarker measurement capacity was performed through CD81 and alpha synuclein assays, as well as dot blot and Western blot analysis. Through this methodology, we have confirmed that nEVs can be isolated from urine and that their biomarkers contents can be measured, supporting urine as a potential non-invasive biomarker source.

Glioblastoma (GBM) is a deadly primary brain tumor with a median survival of 15-18 months after diagnosis. GBM exhibits extensive cell type heterogeneity and interacts with neurons through various mechanisms, including gap junctions and neuron-tumor synapses (NTS). Prior research suggests that input from excitatory glutamatergic NTS can drive high-grade glioma progression. This study investigated how glutamatergic NTS shape GBM cell states using a developed synapse-optimized human organoid tumor transplantation (so-HOTT) GBM model, a stem-cell-derived cortical organoid model transplanted with patient tumor cells. AMPA and kainate receptor signaling was perturbed in tumor cells through an shRNA knockdown of GRIA2 and GRIK3. In parallel, tumor cells were transfected with CellTag, a barcode-based GFP construct, and treated with topiramate (TPM) and UBP310. Single-cell RNA sequencing was used to analyze transcriptional and cell state changes. Dual GRIA2/GRIK3 knockdown increased astrocytic and mesenchymal states while reducing neuronal- and intermediate progenitor cell (IPC)-like states, accompanied by reduced synaptic transmission gene expression and enriched glial fate and hypoxia/stress-associated modules. TPM mimicked genetic perturbation effects, increasing IPC- and radial glia-like populations and promoting cell states with low calcium-associated activity. UBP310 produced weaker, less consistent effects. These findings indicate that glutamatergic NTS regulate GBM cell plasticity and are a potential therapeutic target.

Fentanyl is a synthetic opioid, responsible for the majority of opioid-related deaths. While medication assisted treatments exist, many people relapse within a year of undergoing treatment for opioid use disorder. Vagus nerve stimulation is a promising non-pharmacological approach to treating substance use disorders that has shown benefits in pre-clinical models modulating circuits involved in reward and stress. We developed a wireless, battery-less VNS device which has the potential to significantly improve clinical use of VNS devices. We hypothesize that VNS treatment would reduce stress-induced reinstatement of drug seeking. Male adult rats underwent surgery to implant VNS devices and jugular vein catheters prior learning to press a lever to receive intravenous fentanyl (1.5 µg/kg/infusion). Rats self-administered fentanyl for 10 days prior to undergoing extinction training, where the rats were divided into sham or bluetooth VNS stimulation. After 7 days of extinction training, all rats received Yohimbine (2.5 mg/kg, i.p.) to induce reinstatement of the drug-seeking behavior. All rats learned to self-administer fentanyl and distinguish between active vs the inactive lever within the first 2-3 days of the acquisition phase. All rats extinguished their drug-seeking behavior when fentanyl was not available. The VNS treatment significantly reduced reinstatement of drug seeking behaviors in the presence of the chemical stressor. These findings support VNS as a potential relapse-prevention therapy for opioid use disorder.

An emerging method for regulation of inflammation and parasympathetic function in the body includes the application of transcutaneous vagus nerve stimulation (tVNS). tVNS is a non-invasive method for neuromodulation that has been shown to have effects on the nervous system, particularly when quantifying inflammatory biomarkers and heart rate variability (HRV). To synthesize existing evidence on the efficacy of tVNS in order to predict its efficacy in minimizing post-operative stress for spinal surgery patients a meta-analysis was conducted. The studies selected report the mean and standard deviation data for IL-6, TNF-α, and CRP (inflammatory markers) and for measures of parasympathetic activity such as RMSSSD and HF-HRV. The standardized mean differences and 95% confidence intervals were calculated for each study. Using the fixed-effects model the pooled SMD was calculated. After conducting the analysis, tVNS showed a significant effect size with a SMD= -1.09 and a 95% CI of (-1.36, -0.83). The HRV results indicated an increase in parasympathetic activity and the inflammatory biomarkers demonstrated a reduction after tVNS application. This demonstrates how tVNS can dampen sympathetic dominance and modulate inflammation in the body. Moving forward, tVNS may serve as a therapeutic approach for the mitigation and modulation of nervous system recovery after a traumatic event such as for post-operative spinal surgery patients.

Sleep disorders exhibit prevalent sex differences, with women experiencing more sleep impairments than men. While gonadal hormones like 17β-estradiol and testosterone are known to influence sleep, some sex-specific phenotypes persist in the absence of these hormones. This suggests that the sex chromosome complement may independently regulate sleep, yet the underlying molecular mechanisms remain unknown. This study investigates whether the sex chromosome complement and the Sry gene independently drive estrogen receptor (ERα and ERβ) expression in the suprachiasmatic nucleus (SCN) and ventrolateral preoptic nucleus (VLPO). To decouple chromosomal sex (XX vs. XY) from gonadal sex (testes vs. ovaries), we utilized the Four Core Genotype (FCG) mouse model. mRNA expression in gonadally intact adult mice was quantified using fluorescent in situ hybridization (FISH) and ImageJ analysis. Preliminary results show that ER expression is governed by an interaction between genetic and hormonal sex. Gonadal sex influenced baseline levels, with phenotypic females showing higher ERβ expression, while phenotypic males displayed higher ERα in the SCN. Genotypic males displayed higher overall ER expression than genotypic females, identifying the sex chromosome complement as an independent moderator.