Nervous System Diseases Commons^™

Lovastatin Potentiates The Function Of Α7-Nicotinic Acetylcholine Receptors, Dmytro Isaev, Keun-Hang Susan Yang, Murat Oz

Pharmacy Faculty Articles and Research

Background/Objectives: Statins are currently one of the most commonly used cholesterol-lowering drugs. In recent years, in addition to their well-known effects on the cardiovascular system, statins have been shown to exert beneficial effects in the progression of various neuropsychiatric and neurodegenerative diseases. Methods: In this study, the effects of lovastatin on the function of α7-nicotinic acetylcholine (nACh) receptors expressed in rat hippocampus and Xenopus oocytes were investigated. Results: In whole-cell patch clamp studies in hippocampal neurons, 21-day chronic (20 mg/kg), but not acute (20 min), lovastatin treatment caused significant potentiation of choline (a selective agonist for α7 nACh receptors)-induced currents …

Brain Delivery Of Antibody-Derived Biologicals For Alzheimer’S Disease: An Updated Narrative Review, Rachita K. Sumbria, Ruben J. Boado

Pharmacy Faculty Articles and Research

Antibodies directed against β-amyloid (Aβ) have been developed for the treatment of Alzheimer’s disease (AD). However, the in vivo central efficacy is reduced by the poor penetration of antibodies across the blood–brain barrier (BBB). In addition, these antibodies have been associated with adverse effects like amyloid-related imaging abnormalities. Thus, the development of new antibody-based therapies for AD with improved transport across the BBB may improve efficacy and reduce adverse effects. Antibodies targeting the BBB transferrin receptor (TfR) are able to cross the BBB through receptor-mediated transcytosis, producing a global distribution throughout the brain. Along the same line, bispecific antibodies directed …

Hepatocyte-Specific Lrp1 Silencing Exacerbates Brain Amyloidosis Without Compensatory Ldl Receptor Family Involvement, Brian Carson, Josephine Chu, Devaraj V. Chandrashekar, Jerome Garcia, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Background

LDL receptor related protein 1 (LRP1) is a major hepatic receptor involved in lipoprotein metabolism, protease degradation, transmembrane receptor modulation, and clearance of excess protein, such as Aβ. Decreased expression of LRP1 due to liver injury can impair receptor-mediated clearance, increasing Aβ availability in the periphery. We investigated the effects of hepato-specific silencing of LRP1 on Aβ deposition in the brain. Additionally, other LDL family members (LRP5, LRP6, and LDLR) that may participate in Aβ clearance were monitored in the liver to ensure non-compensatory effects of LRP1 silencing.

Method

4-month-old male double transgenic (APP/PS1) AD mice were injected with …

The Mitochondria Is The Source Of Hepatic Amyloid Precursor Protein And Peripheral Amyloid Beta: Implications Of Alcohol-Induced Liver Steatosis In Alzheimer's Disease, Josephine Chu, Ross A. Steinberg, Brian Carson, Devaraj Venkatapura Chandrashekar, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Background

Alcohol-induced liver injury occurs in the pericentral region of the liver and can induce mitochondrial remodeling and exacerbate Alzheimer's Disease (AD) progression. Subpopulations of mitochondria: general mitochondria (GM), peridroplet mitochondria (PDM) and endoplasmic reticulum(ER)-bound mitochondria (ERM) maintain cellular homeostasis via energy synthesis, lipid homeostasis, and regulation of intracellular calcium. Hepatic amyloid precursor protein (APP) is a source of peripheral amyloid beta (aB) and affects AD pathology in the brain. Understanding the localization and expression of hepatic APP in mitochondrial subpopulations are critical to understanding aB metabolism and may play a role in identifying a potential mechanism for metabolic dysfunction. …

Longitudinal Pharmacokinetic And Safety Studies Of An Antibody-Erythropoietin Fusion Protein For Alzheimer's Disease, Rudy Chang, Devaraj Venkatapura Chandrashekar, G. Chuli Roules, Nataraj Jagadeesan, Emi Iwasaki, Adenike Oyegbesan, Hayk Davtyan, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Erythropoietin (EPO) shows promise for Alzheimer's disease (AD) but has poor brain penetration, necessitating high doses that cause hematopoietic side effects. To improve brain delivery, EPO was fused to a transferrin receptor monoclonal antibody (TfRMAb), and this study evaluated the pharmacokinetics (PK), safety, and efficacy of repeated TfRMAb-EPO dosing in mice to further its preclinical development. C57BL/6J male mice (10 weeks old, n = 4–5/dose) received subcutaneous (SQ) low (1 mg/kg), mid (3 and 6 mg/kg), or high (20 mg/kg) TfRMAb-EPO doses for 4 weeks. The 1 mg/kg dose showed no adverse effects and resulted in sustained brain and plasma …

Predictive Gene Expression Signatures For Alzheimer's Disease Using Post-Mortem Brain Tissue, Ashley Duche, Oliver Tan, Andrius Baskys, Rachita K. Sumbria, Moom R. Roosan

Pharmacy Faculty Articles and Research

Background: Alzheimer’s Disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-beta (Aβ) plaques and tau protein aggregates in the brain. These pathological features manifest in specific regions, but mechanisms rendering some areas more susceptible to early AD-related changes remain poorly understood. To address this, we developed predictive gene expression signatures to explore molecular mechanisms underlying regional vulnerability to AD pathology.

Methods: Post-mortem brain tissues from participants of the Religious Orders Study and Memory and Aging Project (ROSMAP), Mayo Clinic, and Mount Sinai Brain Bank (MSBB) were used to derive gene expression signatures from six brain regions affected at varying …

Effect Of Chronic Alcohol Feeding Using The Lieber-Decarli Diet On Alzheimer’S Disease Pathology In Tg2576 Mice, Devaraj V. Chandrashekar, Nataraj Jagadeesan, Tamara Abdullah, Rudy Chang, Ross A. Steinberg, Frankey Sanchez, Elias Khal, Joshua Yang, David H. Cribbs, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background: Chronic alcohol drinking is a modifiable risk factor for Alzheimer’s disease (AD), but underlying mechanisms remain poorly understood. Most studies of alcohol feeding to AD mice have utilized young mice and delivered alcohol in drinking water without controlling nutritional intake.

Objective: To study the impact of Lieber-DeCarli (LDC) liquid alcohol diet, which balances nutritional intake, on AD pathology of aged Tg2576 and wild-type (WT) mice, which is unexplored.

Methods: 13-month-old male and female Tg2576 or WT mice were fed LDC diet (5% ethanol or control) for six weeks (n = 11-13/group). Exploration (open-field test) and spatial reference memory …

Bile Duct Ligation-Induced Cirrhosis Does Not Alter The Blood-Brain Barrier Permeability To Sucrose In Rats, Mohammad K. Miah, Ulrich Bickel, Reza Mehvar

Pharmacy Faculty Articles and Research

Contradictory results have been reported about the effects of liver diseases on the blood-brain barrier (BBB) permeability to markers. For instance, both an increase and no change in the BBB permeability to BBB markers sodium fluorescein and Evans blue have been reported in experimental cholestasis induced by bile duct ligation (BDL) in rats. These contradictory effects might be due to inherent limitations of these markers and/or methodological issues. Here, we investigated the time course of the impact of BDL in rats on BBB permeability using a recently developed stable isotope labeled marker [¹³C]sucrose, which is expected to be …

Hepatic Lrp-1 Plays An Important Role In Amyloidosis In Alzheimer's Disease Mice: Potential Role In Chronic Heavy Alcohol Feeding, Devaraj V. Chandrashekar, G. Chuli Roules, Nataraj Jagadeesan, Urvashi R. Panchal, Adenike Oyegbesan, Oghenetega E. Imiruaye, Hai Zhang, Jerome Garcia, Kamaljit Kaur, Sanda Win, Tin A. Than, Neil Kaplowitz, Moom R. Roosan, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Methods

Modulation Of Hippocampal Protein Expression By A Brain Penetrant Biologic Tnf-Α Inhibitor In The 3xtg Alzheimer’S Disease Mice, Nataraj Jagadeesan, G. Chuli Roules, Devaraj V. Chandrashekar, Joshua Yang, Sanjana Kolluru, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Biologic TNF-α inhibitors (bTNFIs) can block cerebral TNF-α in Alzheimer’s disease (AD) if these macromolecules can cross the blood–brain barrier (BBB). Thus, a model bTNFI, the extracellular domain of type II TNF-α receptor (TNFR), which can bind to and sequester TNF-α, was fused with a mouse transferrin receptor antibody (TfRMAb) to enable brain delivery via BBB TfR-mediated transcytosis. Previously, we found TfRMAb-TNFR to be protective in a mouse model of amyloidosis (APP/PS1) and tauopathy (PS19), and herein we investigated its effects in mice that combine both amyloidosis and tauopathy (3xTg-AD).

Methods

Eight-month-old female 3xTg-AD mice were injected intraperitoneally with …

Oxidative Stress And Ion Channels In Neurodegenerative Diseases, Razan Orfali, Adnan Z. Alwatban, Rawan S. Orfali, Liz Lau, Noble Chea, Abdullah M. Alotaibi, Young-Woo Nam, Miao Zhang

Pharmacy Faculty Articles and Research

Numerous neurodegenerative diseases result from altered ion channel function and mutations. The intracellular redox status can significantly alter the gating characteristics of ion channels. Abundant neurodegenerative diseases associated with oxidative stress have been documented, including Parkinson’s, Alzheimer’s, spinocerebellar ataxia, amyotrophic lateral sclerosis, and Huntington’s disease. Reactive oxygen and nitrogen species compounds trigger posttranslational alterations that target specific sites within the subunits responsible for channel assembly. These alterations include the adjustment of cysteine residues through redox reactions induced by reactive oxygen species (ROS), nitration, and S-nitrosylation assisted by nitric oxide of tyrosine residues through peroxynitrite. Several ion channels have been directly …

Erythrocyte–Brain Endothelial Interactions Induce Microglial Responses And Cerebral Microhemorrhages In Vivo, Hai Zhang, Rachita K. Sumbria, Rudy Chang, Jiahong Sun, David H. Cribbs, Todd C. Holmes, Mark J. Fisher, Xiangmin Xu

Pharmacy Faculty Articles and Research

Background

Cerebral microhemorrhages (CMH) are associated with stroke, cognitive decline, and normal aging. Our previous study shows that the interaction between oxidatively stressed red blood cells (RBC) and cerebral endothelium may underlie CMH development. However, the real-time examination of altered RBC–brain endothelial interactions in vivo, and their relationship with clearance of stalled RBC, microglial responses, and CMH development, has not been reported.

Methods

RBC were oxidatively stressed using tert-butylhydroperoxide (t-BHP), fluorescently labeled and injected into adult Tie2-GFP mice. In vivo two-photon imaging and ex vivo confocal microscopy were used to evaluate the temporal profile of RBC–brain endothelial interactions associated with …

Tolfenamic Acid Derivatives: A New Class Of Transcriptional Modulators With Potential Therapeutic Applications For Alzheimer’S Disease And Related Disorders, Juanetta Hill, Karim E. Shalaby, Syed W. Bihaqi, Bothaina H. Alansi, Benjamin Barlock, Keykavous Parang, Richard Thompson, Khalid Ourarhni, Nasser H. Zawia

Pharmacy Faculty Articles and Research

The field of Alzheimer’s disease (AD) has witnessed recent breakthroughs in the development of disease-modifying biologics and diagnostic markers. While immunotherapeutic interventions have provided much-awaited solutions, nucleic acid-based tools represent other avenues of intervention; however, these approaches are costly and invasive, and they have serious side effects. Previously, we have shown in AD animal models that tolfenamic acid (TA) can lower the expression of AD-related genes and their products and subsequently reduce pathological burden and improve cognition. Using TA as a scaffold and the zinc finger domain of SP1 as a pharmacophore, we developed safer and more potent brain-penetrating analogs …

Sirna Drug Delivery Across The Blood–Brain Barrier In Alzheimer's Disease, Muhammad Imran Sajid, Fahad Sultan Sheikh, Faiza Anis, Nourina Nasim, Rachita K. Sumbria, Surya M. Nauli, Rakesh K. Tiwari

Pharmacy Faculty Articles and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disease with a few FDA-approved drugs that provide modest symptomatic benefits and only two FDA-approved disease-modifying treatments for AD. The advancements in understanding the causative genes and non-coding sequences at the molecular level of the pathophysiology of AD have resulted in several exciting research papers that employed small interfering RNA (siRNA)-based therapy. Although siRNA is being sought by academia and biopharma industries, several challenges still need to be addressed. We comprehensively report the latest advances in AD pathophysiology, druggable targets, ongoing clinical trials, and the siRNA-based approaches across the blood–brain barrier for addressing …

Alcohol As A Modifiable Risk Factor For Alzheimer’S Disease—Evidence From Experimental Studies, Devaraj V. Chandrashekar, Ross A. Steinberg, Derick Han, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Alzheimer’s disease (AD) is a progressive neurodegenerative disease characterized by cognitive impairment and memory loss. Epidemiological evidence suggests that heavy alcohol consumption aggravates AD pathology, whereas low alcohol intake may be protective. However, these observations have been inconsistent, and because of methodological discrepancies, the findings remain controversial. Alcohol-feeding studies in AD mice support the notion that high alcohol intake promotes AD, while also hinting that low alcohol doses may be protective against AD. Chronic alcohol feeding to AD mice that delivers alcohol doses sufficient to cause liver injury largely promotes and accelerates AD pathology. The mechanisms by which alcohol can …

The Effects Of A Blood–Brain Barrier Penetrating Erythropoietin In A Mouse Model Of Tauopathy, Joshua Yang, Weijun Ou, Nataraj Jagadeesan, Juste Simanauskaite, Jiahong Sun, Demi M. Castellanos, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Erythropoietin (EPO), a hematopoietic neurotrophin, is a potential therapeutic for Alzheimer’s disease (AD) but has limited blood–brain barrier (BBB) permeability. EPO fused to a chimeric transferrin receptor monoclonal antibody (cTfRMAb) enters the brain via TfR-mediated transcytosis across the BBB. We previously showed that cTfRMAb-EPO is protective in a mouse model of amyloidosis, but its effects on tauopathy are not known. Given that amyloid and tau pathology are characteristics of AD, the effects of cTfRMAb-EPO were studied in a tauopathy mouse model (PS19). Six-month-old PS19 mice were injected intraperitoneally with either saline (PS19-Saline; n = 9) or cTfRMAb-EPO (PS19-cTfRMAb-EPO, 10 mg/kg; …

Chronic Kidney Disease Promotes Cerebral Microhemorrhage Formation, Chuo Fang, Wei Ling Lau, Jiahong Sun, Rudy Chang, Adrian Vallejo, Donghy Lee, Jihua Liu, Han Liu, Yu-Han Hung, Yitong Zhao, Annlia Paganini-Hill, Rachita K. Sumbria, David H. Cribbs, Mark J. Fisher

Pharmacy Faculty Articles and Research

Background

Chronic kidney disease (CKD) is increasingly recognized as a stroke risk factor, but its exact relationship with cerebrovascular disease is not well-understood. We investigated the development of cerebral small vessel disease using in vivo and in vitro models of CKD.

Methods

CKD was produced in aged C57BL/6J mice using an adenine-induced tubulointerstitial nephritis model. We analyzed brain histology using Prussian blue staining to examine formation of cerebral microhemorrhage (CMH), the hemorrhagic component of small vessel disease and the neuropathological substrate of MRI-demonstrable cerebral microbleeds. In cell culture studies, we examined effects of serum from healthy or CKD patients and …

Efficacy And Safety Of A Brain-Penetrant Biologic Tnf-Α Inhibitor In Aged App/Ps1 Mice, Weijun Ou, Yuu Ohno, Joshua Yang, Devaraj V. Chandrashekar, Tamara Abdullah, Jiahong Sun, Riley Murphy, Chuli Roules, Nataraj Jagadeesan, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Tumor necrosis factor alpha (TNF-α) plays a vital role in Alzheimer’s disease (AD) pathology, and TNF-α inhibitors (TNFIs) modulate AD pathology. We fused the TNF-α receptor (TNFR), a biologic TNFI that sequesters TNF-α, to a transferrin receptor antibody (TfRMAb) to deliver the TNFI into the brain across the blood–brain barrier (BBB). TfRMAb-TNFR was protective in 6-month-old transgenic APP/PS1 mice in our previous work. However, the effects and safety following delayed chronic TfRMAb-TNFR treatment are unknown. Herein, we initiated the treatment when the male APP/PS1 mice were 10.7 months old (delayed treatment). Mice were injected intraperitoneally with saline, TfRMAb-TNFR, etanercept (non-BBB-penetrating …

Modulation Of Hepatic Amyloid Precursor Protein And Lipoprotein Receptor-Related Protein 1 By Chronic Alcohol Intake: Potential Link Between Liver Steatosis And Amyloid-Β, Jerome Garcia, Rudy Chang, Ross A. Steinberg, Aldo Arce, Joshua Yang, Peter Van Der Eb, Tamara Abdullah, Devaraj V. Chandrashekar, Syndey M. Eck, Pablo Meza, Zhang-Xu Liu, Enrique Cadenas, David H. Cribbs, Neil Kaplowitz, Rachita K. Sumbria, Derick Han

Pharmacy Faculty Articles and Research

Heavy alcohol consumption is a known risk factor for various forms of dementia and the development of Alzheimer’s disease (AD). In this work, we investigated how intragastric alcohol feeding may alter the liver-to-brain axis to induce and/or promote AD pathology. Four weeks of intragastric alcohol feeding to mice, which causes significant fatty liver (steatosis) and liver injury, caused no changes in AD pathology markers in the brain [amyloid precursor protein (APP), presenilin], except for a decrease in microglial cell number in the cortex of the brain. Interestingly, the decline in microglial numbers correlated with serum alanine transaminase (ALT) levels, suggesting …

Full- Versus Sub-Regional Quantification Of Amyloid-Beta Load On Mouse Brain Sections, Yuu Ohno, Riley Murphy, Matthew Choi, Weijun Ou, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Extracellular accumulation of amyloid-beta (Aβ) plaques is one of the major pathological hallmarks of Alzheimer's disease (AD), and is the target of the only FDA-approved disease-modifying treatment for AD. Accordingly, the use of transgenic mouse models that overexpress the amyloid precursor protein and thereby accumulate cerebral Aβ plaques are widely used to model human AD in mice. Therefore, immunoassays, including enzyme-linked immunosorbent assay (ELISA) and immunostaining, commonly measure the Aβ load in brain tissues derived from AD transgenic mice. Though the methods for Aβ detection and quantification have been well established and documented, the impact of the size of the …

Author Correction: Short Amylin Receptor Antagonist Peptides Improve Memory Deficits In Alzheimer’S Disease Mouse Model, Rania Soudy, Ryoichi Kimura, Aarti Patel, Wen Fu, Kamaljit Kaur, David Westaway, Jing Yang, Jack Jhamandas

Pharmacy Faculty Articles and Research

Correction to: Scientific Reports https://doi.org/10.1038/s41598-019-47255-9, published online 29 July 2019

The original Article contained an error in Figure 1A where the control trace for both the HEK-AMY3 and HEKWT cells was duplicated...

The original Article has been corrected.

A Pdk-1 Allosteric Agonist Neutralizes Insulin Signaling Derangements And Beta-Amyloid Toxicity In Neuronal Cells And In Vitro, Henry Querfurth, John Marshall, Keykavous Parang, Mengia S. Rioult-Pedotti, Rakesh Tiwari, Bumsup Kwon, Steve Reisinger, Han-Kyu Lee

Pharmacy Faculty Articles and Research

The Alzheimer’s brain is affected by multiple pathophysiological processes, which include a unique, organ-specific form of insulin resistance that begins early in its course. An additional complexity arises from the four-fold risk of Alzheimer’s Disease (AD) in type 2 diabetics, however there is no definitive proof of causation. Several strategies to improve brain insulin signaling have been proposed and some have been clinically tested. We report findings on a small allosteric molecule that reverses several indices of insulin insensitivity in both cell culture and in vitro models of AD that emphasize the intracellular accumulation of β-amyloid (Aβi). PS48, a chlorophenyl …

Biologic Tnf-Α Inhibitors Reduce Microgliosis, Neuronal Loss, And Tau Phosphorylation In A Transgenic Mouse Model Of Tauopathy, Weijun Ou, Joshua Yang, Juste Simanauskaite, Matthew Choi, Demi M. Castellanos, Rudy Chang, Jiahong Sun, Nataraj Jagadeesan, Karen D. Parfitt, David H. Cribbs, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Background

Tumor necrosis factor-α (TNF-α) plays a central role in Alzheimer’s disease (AD) pathology, making biologic TNF-α inhibitors (TNFIs), including etanercept, viable therapeutics for AD. The protective effects of biologic TNFIs on AD hallmark pathology (Aβ deposition and tau pathology) have been demonstrated. However, the effects of biologic TNFIs on Aβ-independent tau pathology have not been reported. Existing biologic TNFIs do not cross the blood–brain barrier (BBB), therefore we engineered a BBB-penetrating biologic TNFI by fusing the extracellular domain of the type-II human TNF-α receptor (TNFR) to a transferrin receptor antibody (TfRMAb) that ferries the TNFR into the brain via …

Novel Biomarkers Of Ciliary Extracellular Vesicles Interact With Ciliopathy And Alzheimer’S Associated Proteins, Ashraf M. Mohieldin, Amal Alachkar, John R. Yates Iii, Surya M. Nauli

Pharmacy Faculty Articles and Research

Ciliary extracellular vesicles (ciEVs), released from primary cilia, contain functional proteins that play an important role in cilia structure and functions. We have recently shown that ciEVs and cytosolic extracellular vesicles (cyEVs) have unique and distinct biomarkers. While ciEV biomarkers have shown some interactions with known ciliary proteins, little is known about the interaction of ciEV proteins with proteins involved in ciliopathy and neurodegenerative disorders. Here, we reveal for the first time the protein-protein interaction (PPI) between the top five ciEVs biomarkers with ciliopathy and Alzheimer disease (AD) proteins. These results support the growing evidence of the critical physiological roles …

The Concentration Of Brain Homogenates With The Amicon Ultra Centrifugal Filters, Joshua Yang, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Accurately measuring the brain concentration of a neurotherapeutic is critical in determining its pharmacokinetic profile in vivo. Biologics are potential therapeutics for neurologic diseases and biologics fused to an antibody targeting a transcytosis receptor at the Blood-Brain Barrier, designated as antibody-biologic fusion proteins, are Blood-Brain Barrier penetrating neurotherapeutics. The use of sandwich immunosorbent assays to measure concentrations of antibody-biologic fusion proteins in brain homogenates has become increasingly popular. The raw brain homogenate contains many proteins and other macromolecules that can cause a matrix effect, potentially interfering with the limit of detection of such assays and reduce the overall sample …

Scoping Review: The Empowerment Of Alzheimer’S Disease Caregivers With Mhealth Applications, Eunhee Kim, Andrius Baskys, Anandi V. Law, Moom R. Roosan, Yan Li, Don Roosan

Pharmacy Faculty Articles and Research

Alzheimer’s Disease (AD) is one of the most prevalent neurodegenerative chronic diseases. As it progresses, patients become increasingly dependent, and their caregivers are burdened with the increasing demand for managing their care. Mobile health (mHealth) technology, such as smartphone applications, can support the need of these caregivers. This paper examines the published academic literature of mHealth applications that support the caregivers of AD patients. Following the PRISMA for scoping reviews, we searched published literature in five electronic databases between January 2014 and January 2021. Twelve articles were included in the final review. Six themes emerged based on the functionalities provided …

Insights Into The Mechanisms Of Brain Endothelial Erythrophagocytosis, Jiahong Sun, Prema Vyas, Samar Mann, Annlia Paganini-Hill, Ane C. F. Nunes, Wei Ling Lau, David H. Cribbs, Mark J. Fisher, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

The endothelial cells which form the inner cellular lining of the vasculature can act as non-professional phagocytes to ingest and remove emboli and aged/injured red blood cells (RBCs) from circulation. We previously demonstrated an erythrophagocytic phenotype of the brain endothelium for oxidatively stressed RBCs with subsequent migration of iron-rich RBCs and RBC degradation products across the brain endothelium in vivo and in vitro, in the absence of brain endothelium disruption. However, the mechanisms contributing to brain endothelial erythrophagocytosis are not well defined, and herein we elucidate the cellular mechanisms underlying brain endothelial erythrophagocytosis. Murine brain microvascular endothelial cells (bEnd.3 …

Acute And Chronic Dosing Of A High-Affinity Rat/Mouse Chimeric Transferrin Receptor Antibody In Mice, Demi M. Castellanos, Jiahong Sun, Joshua Yang, Weijun Ou, Alexander C. Zambon, William M. Pardridge, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

Non-invasive brain delivery of neurotherapeutics is challenging due to the blood-brain barrier. The revived interest in transferrin receptor antibodies (TfRMAbs) as brain drug-delivery vectors has revealed the effect of dosing regimen, valency, and affinity on brain uptake, TfR expression, and Fc-effector function side effects. These studies have primarily used monovalent TfRMAbs with a human constant region following acute intravenous dosing in mice. The effects of a high-affinity bivalent TfRMAb with a murine constant region, without a fusion partner, following extravascular dosing in mice are, however, not well characterized. Here we elucidate the plasma pharmacokinetics and safety of a high-affinity bivalent …

Targeting The Transferrin Receptor To Develop Erythropoietin For Alzheimer’S Disease, Rachita K. Sumbria

Pharmacy Faculty Articles and Research

"Alzheimer’s disease (AD) is the sixth leading cause of death in the United States with approximately 5.8 million Americans currently living with AD. Due to the lack of a disease modifying treatment for AD and the aging baby boomer generation, this number is projected to grow to 13.8 million by 2050 (Gaugler et al., 2019). Amyloid-beta (Aβ) plaque accumulation, one of the major pathological hallmarks of AD, can begin > 20 years before clinical symptoms of AD. By the time AD is clinically diagnosed, neuronal loss and neuropathological lesions (Aβ plaques and tau tangles) have already occurred in many brain regions …

Effects Of Dabigatran In Mouse Models Of Aging And Cerebral Amyloid Angiopathy, Neethu Michael, Mher Mahoney Grigoryan, Kelley Kilday, Rachita K. Sumbria, Vitaly Vasilevko, Joanne Van Ryn, David H. Cribbs, Annlia Paganini-Hill, Mark J. Fisher

Pharmacy Faculty Articles and Research

Oral anticoagulants are a critical component of stroke prevention, but carry a risk of brain hemorrhage. These hemorrhagic complications tend to occur in elderly individuals, especially those with predisposing conditions such as cerebral amyloid angiopathy (CAA). Clinical evidence suggests that non-vitamin K antagonist oral anticoagulants are safer than traditional oral anticoagulants. We analyzed whether the anticoagulant dabigatran produces cerebral microhemorrhage (the pathological substrate of MRI-demonstrable cerebral microbleeds) or intracerebral hemorrhage in aged mice with and without hemorrhage-predisposing angiopathy. We studied aged (22 months old) Tg2576 (a model of CAA) and wild-type (WT) littermate mice. Mice received either dabigatran etexilate (DE) …