Developmental Neuroscience Commons^™

Cognitive Decline, Aβ Pathology, And Blood–Brain Barrier Function In Aged 5xfad Mice, Geetika Nehra, Sasivimon Promsan, Ruedeemars Yubolphan, Wijitra Chumboatong, Pornpun Vivithanaporn, Bryan J. Maloney, Anusorn Lungkaphin, Bjoern Bauer, Anika M. S. Hartz

Markey Cancer Center Faculty Publications

Background

Patients with Alzheimer’s disease (AD) develop blood–brain barrier dysfunction to varying degrees. How aging impacts Aβ pathology, blood–brain barrier function, and cognitive decline in AD remains largely unknown. In this study, we used 5xFAD mice to investigate changes in Aβ levels, barrier function, and cognitive decline over time.

Methods

5xFAD and wild-type (WT) mice were aged between 9.5 and 15.5 months and tested for spatial learning and reference memory with the Morris Water Maze (MWM). After behavior testing, mice were implanted with acute cranial windows and intravenously injected with fluorescent-labeled dextrans to assess their in vivo distribution in the …

Oxidative Stress Alters Mitochondrial Homeostasis In Isolated Brain Capillaries, Gopal V. Velmurugan, Hemendra J. Vekaria, Anika M. S. Hartz, Björn Bauer, William Brad Hubbard

Markey Cancer Center Faculty Publications

Background

Neurovascular deficits and blood-brain barrier (BBB) dysfunction are major hallmarks of brain trauma and neurodegenerative diseases. Oxidative stress is a prominent contributor to neurovascular unit (NVU) dysfunction and can propagate BBB disruption. Oxidative damage results in an imbalance of mitochondrial homeostasis, which can further drive functional impairment of brain capillaries. To this end, we developed a method to track mitochondrial-related changes after oxidative stress in the context of neurovascular pathophysiology as a critical endophenotype of neurodegenerative diseases.

Methods

To study brain capillary-specific mitochondrial function and dynamics in response to oxidative stress, we developed an ex vivo model in which …

Proteasome Inhibition Protects Blood–Brain Barrier P-Glycoprotein And Lowers Aβ Brain Levels In An Alzheimer’S Disease Model, Milica Vulin, Yu Zhong, Bryan J. Maloney, Björn Bauer, Anika M. S. Hartz

Markey Cancer Center Faculty Publications

Background Loss of P-glycoprotein (P-gp) at the blood–brain barrier contributes to amyloid-β (Aβ) brain accumulation in Alzheimer’s disease (AD). Using transgenic human amyloid precursor protein (hAPP)-overexpressing mice (Tg2576), we previously showed that Aβ triggers P-gp loss by activating the ubiquitin–proteasome pathway, which leads to P-gp degradation. Furthermore, we showed that inhibiting the ubiquitin-activating enzyme (E1) prevents P-gp loss and lowers Aβ accumulation in the brain of hAPP mice. Based on these data, we hypothesized that repurposing the FDA-approved proteasome inhibitor, bortezomib (Velcade®; BTZ), protects blood–brain barrier P-gp from degradation in hAPP mice in vivo.

Methods We treated hAPP mice with …