Geriatrics Commons^™

Dark And Camouflaged Genomic Regions Remain Challenging In Chm13, Mark E. Wadsworth, Madeline L. Page, Bernardo Aguzzoli Heberle, Justin B. Miller, Cody J. Steely, Mark T. W. Ebbert

Sanders-Brown Center on Aging Faculty Publications

Comprehensive genomic analysis is essential for advancing our understanding of human genetics and disease. However, short-read sequencing technologies are inherently limited in their ability to resolve highly repetitive, structurally complex, and low-mappability genomic regions, previously coined as “dark” regions. Long-read sequencing technologies, such as PacBio and Oxford Nanopore Technologies (ONT), offer improved resolution of these regions, yet they are not perfect. With the advent of the new Telomere-to-Telomere (T2T) CHM13 reference genome, exploring its effect on dark regions is prudent. In this study, we systematically analyze dark regions across four human genome references—HG19, HG38 (with and without alternate contigs), and …

Data-Driven Thresholds For Standardized Classification Of Severe Alzheimer’S Disease Neuropathology Using Digital Neuropathology, Ryan K. Shahidehpour, Allison M. Neltner, Mitchell A. Klusty, Cole Corbett, Angelique D. Gonzalez, David A. Gutman, David W. Fardo, Adam D. Bachstetter, Cody Bumgardner, Margaret E. Flanagan, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

Alzheimer's disease neuropathological changes (ADNC)—operationalized with semi-quantitative parameters—represent the consensus-based gold standard for diagnostic evaluation of disease severity. Although useful, ADNC diagnostic frameworks have limitations, particularly in advanced disease stages where pathological severity varies widely within a given diagnostic category. Further, some individuals lacking cognitive impairment are inappropriately categorized as having severe ADNC. In this study, quantitative pathology metrics and alternative tissue sampling schemes were integrated with data about premortem cognitive status, in order to derive clinically informed neuropathologic diagnostic thresholds. Specific goals of the current study were to generate data-driven, standardized diagnostic cut-points, with the most severe stages of …

Clonal Expansion Of Cytotoxic Cd8⁺ T Cells In Lecanemab-Associated Aria, Lance A. Johnson, Kai Saito, Akhil V. Pallerla, Jessica L. Funnell, Ashley R. Ezzo, Chelsea M. Song, Douglas A. Harrison, Noah J. Norton, Lauren C. Moore, Linda J. Van Eldik, David W. Fardo, Greg E. Cooper, Josh M. Morganti

Sanders-Brown Center on Aging Faculty Publications

Amyloid-related imaging abnormalities (ARIA) are the principal safety concern limiting anti-amyloid therapies for Alzheimer’s disease, yet their biology remains unclear. Here we show, through multi-omic profiling of peripheral blood from three ARIA+ patients and matched controls, that ARIA is associated with coordinated reprogramming of CD8 + T cells. CD8+ effector memory (TEM) and terminally differentiated (TEMRA) subsets were expanded, clonally enriched, and transcriptionally primed for cytotoxicity and vascular trafficking. Transcription factor inference and metabolomics converged on glycolytic reprogramming favoring short-lived effector function. Ligand-receptor modeling revealed enhanced monocyte-to-T cell signaling through antigen presentation, adhesion, and chemokine axes, while integration with a …

Apoe4 Drives Maladaptive Heterogeneity And Immunometabolic Responses Of Astrocytes, Danielle S. Goulding, Holden C. Williams, Amy A. Gorman, Nicholas A. Devanney, Douglas A. Harrison, Adeline E. Walsh, Tony Tuck, Diana J. Zajac, Shannon L. Macauley, Steven Estus, Julia Tcw, Lance A. Johnson, Josh M. Morganti

Sanders-Brown Center on Aging Faculty Publications

Apolipoprotein E4 (APOE4) is the strongest risk allele associated with the development of late onset Alzheimer’s disease (AD). Across the CNS, astrocytes are the predominant expressor of APOE while also being critical mediators of neuroinflammation and cerebral metabolism. APOE4 has been consistently linked with dysfunctional inflammation and metabolic processes, yet insights into the molecular constituents driving these responses remain unclear. Utilizing complementary approaches across humanized APOE mice and isogenic human iPSC astrocytes, we demonstrate that ApoE4 alters the astrocyte immunometabolic response to pro-inflammatory stimuli. Our findings show that ApoE4-expressing astrocytes acquire distinct transcriptional repertoires at single-cell and spatially-resolved domains, which …

Dual Orexin Receptor Antagonism With Lemborexant Enhances Microglial Clearance Of Β-Amyloid In Mice, Ashish Sharma, Emiko Segawa, Xiaoying Chen, Sohui Park, Shoutang Wang, Riley E. Irmen, Nicholas J. Constantino, Chanung Wang, Michael F. Kanan, Marco Colonna, Shannon L. Macauley, Jocelyn Y. Cheng, Ken Hatanaka, Margaret Moline, Erik S. Musiek

Sanders-Brown Center on Aging Faculty Publications

Background: Sleep disturbances elevate brain amyloid-beta (Aβ) levels and represent a modifiable risk factor for Alzheimer’s disease (AD). The orexin/hypocretin system regulates sleep–wake behavior and has emerged as a therapeutic target in AD; however, the effects of FDA-approved dual orexin receptor antagonists (DORAs) on amyloid pathology remain unclear. We compared lemborexant, an FDA-approved DORA, to doxepin, an antihistaminergic sleep medication, on amyloid pathology and microglial responses in PSAPP mice.

Methods: PSAPP mice received lemborexant (10 or 30 mg/kg/day), doxepin (35 mg/kg/day), or vehicle for 6 weeks beginning prior to plaque onset or 4 weeks after established pathology. Sleep was assessed …

Synergistic Effects Of Plasma S100b And Mri Measures Of Cerebrovascular Disease On Cognition In Older Adults, Colleen A. Pappas, Christopher E. Bauer, Valentinos Zachariou, Timothy Justin Libecap, Beatriz Rodolpho, Tiffany L. Sudduth, Peter T. Nelson, Gregory Jicha, Anika M. S. Hartz, Xingfeng Shao, Danny J. J. Wang, Brian T. Gold

Neurology Faculty Publications

There is growing interest in studying vascular contributions to cognitive impairment and dementia (VCID) and developing biomarkers to identify at-risk individuals. A combination of biofluid and neuroimaging markers may better profile early stage VCID than individual measures. Here, we tested this possibility focusing on plasma levels of S100 calcium-binding protein B (S100B), which has been linked with blood– brain-barrier (BBB) integrity, and neuroimaging measures assessing BBB function (water exchange rate across the BBB (kw)) and cerebral small vessel disease (white matter hyperintensities (WMHs)). A total of 74 older adults without dementia had plasma samples collected and underwent cognitive assessment. A …

Exploring The Links Among Brain Iron Accumulation, Cognitive Performance, And Dietary Intake In Older Adults: A Longitudinal Mri Study, Valentinos Zachariou, Colleen A. Pappas, Christopher E. Bauer, Elayna R. Seago, Brian T. Gold

Neurology Faculty Publications

This study evaluated longitudinal brain iron accumulation in older adults, its association with cognition, and the role of specific nutrients in mitigating iron accumulation. MRI-based, quantitative susceptibility mapping estimates of brain iron concentration were acquired from seventy-two healthy older adults (47 women, ages 60–86) at a baseline timepoint (TP1) and a follow-up timepoint (TP2) 2.5–3.0 years later. Dietary intake was evaluated at baseline using a validated questionnaire. Cognitive performance was assessed at TP2 using the uniform data set (Version 3) neuropsychological tests of episodic memory (MEM) and executive function (EF). Voxel-wise, linear mixed-effects models, adjusted for longitudinal gray matter volume …

Blood Biomarkers In Down Syndrome: Facilitating Alzheimer’S Disease Detection And Monitoring, Melissa E. Petersen, Lisi Flores-Aguilar, Elizabeth Head, Laia Montoliu-Gaya, Andre Strydom, Sarah E. Pape, Juan Fortea, Nicholas J. Ashton, Chinedu Udeh-Momoh, Sid E. O’Bryant, Dwight German, Florin Despa, Mark Mapstone, Henrik Zetterberg

Neurology Faculty Publications

Blood-based biomarkers continue to be explored for disease detection, monitoring of progression, and therapeutic outcomes as the diagnostic determination of Alzheimer’s Disease in Down Syndrome (DS-AD) remains challenging in clinical settings. This perspective highlights the current status of this effort. Overall, amyloid (A), tau (T), and neurodegeneration (AT[N]) blood-based biomarkers have been shown to increase with disease pathology for individuals with DS. Phosphorylated tau biomarkers (p-tau217, p-tau181) have been consistently shown to track disease progression for DS-AD and are likely good candidates for use in clinical settings. Biomarkers of inflammation (glial fibrillary acidic protein) also show promise; however, additional work …

Early Changes In Inflammation-Related Proteins In The Cerebrospinal Fluid And Plasma Of Patients With Aneurysmal Subarachnoid Hemorrhage, David J. Braun, Kevin W. Hatton, Justin F. Fraser, Robert M. Flight, Hunter N. B. Moseley, Caleb S. Bailey, Josh M. Morganti, Bingqing Zhang, Ishara S. Ariyapala, Tae K. Kim, Linda J. Van Eldik

Sanders-Brown Center on Aging Faculty Publications

Background

Aneurysmal subarachnoid hemorrhage (aSAH) is a relatively uncommon but high mortality form of stroke that can result in long-lasting disability. A better understanding of key neuroinflammatory changes during the early phase (< 72 h) may provide potential avenues of treatment.

Methods

In an attempt to understand these early changes, we recruited 7 aSAH patients for profiling of longitudinal plasma and cerebrospinal fluid (CSF) proteins at up to 72 h post injury. We additionally compared this to control plasma obtained previously from healthy elderly volunteers. Using the Alamar Biosciences NULISAseq platform, we obtained a comprehensive picture of early peripheral and central inflammatory changes after injury.

Results

This study …

Nicorandil Treatment Improves Survival And Spatial Learning In Aged Granulin Knockout Mice, Dana M. Niedowicz, Wang-Xia Wang, Paresh Prajapati, Yu Zhong, Shuling X. Fister, Colin B. Rogers, Pradoldej Sompol, David K. Powell, Indumati Patel, Christopher M. Norris, Kathryn E. Saatman, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

Mutations in the human granulin (GRN) gene are associated with multiple diseases, including dementia disorders such as frontotemporal dementia (FTD) and limbic-predominant age-related TDP-43 encephalopathy (LATE). We studied a Grn knockout (Grn-KO) mouse model in order to evaluate a potential therapeutic strategy for these diseases using nicorandil, a commercially available agonist for the ABCC9/Abcc9-encoded regulatory subunit of the “K⁺ATP” channel that is well-tolerated in humans. Aged (13 months) Grn-KO and wild-type (WT) mice were treated as controls or with nicorandil (15 mg/kg/day) in drinking water for 7 months, then tested for neurobehavioral …

Gait Variability As A Marker Of White Matter Integrity In Individuals With Down Syndrome, Elizabeth M. Leach, David K. Powell, Amanda C. Glueck, Elizabeth Head, Moaz W. Ibrahim, Amelia J. Anderson-Mooney, Kathryn L. Van Pelt, Jordan P. Harp, Frederick A. Schmitt, Ahmed A. Bahrani

Sanders-Brown Center on Aging Faculty Publications

Introduction: Individuals with Down syndrome (DS) face a significant risk of neurodegeneration, and gait variability may serve as a clinical biomarker of neurological health. This longitudinal parent substudy aimed to explore relationships between gait, white matter (WM) integrity, and cognitive function in DS.

Methods: The associations were investigated between magnetic resonance imaging diffusion tensor imaging (DTI), cognition, and self-paced gait data from 22 DS participants (mean age ± SD 37 ± 7.5 years).

Results: DTI measures, such as lower fractional anisotropy (FA) and higher mean diffusivity, were correlated with greater step time variability but not normalized velocities. Lower cognitive scores …

Disrupted Calcium Dynamics In Reactive Astrocytes Occur With End Feet–Arteriole Decoupling In An Amyloid Mouse Model Of Alzheimer’S Disease, Blaine Weiss, John C. Gant, Ruei-Lung Lin, Jenna L. Gollihue, Colin B. Rogers, Susan D. Kraner, Edmund B. Rucker, Yuriko Katsumata, Yang Jiang, Peter T. Nelson, Donna M. Wilcock, Pradoldej Sompol, Olivier Thibault, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

While cerebrovascular dysfunction and reactive astrocytosis are extensively characterized hallmarks of Alzheimer's disease (AD) and related dementias, the dynamic relationship between reactive astrocytes and cerebral vessels remains poorly understood. Here, we used jGCaMP8f and two-photon microscopy to investigate calcium signaling in multiple astrocyte subcompartments, concurrent with changes in cerebral arteriole activity, in fully awake 7- to 8-month-old male and female 5xFAD mice, a model for AD-like pathology, and wild-type (WT) littermates. In the absence of movement, spontaneous calcium transients in barrel cortex occurred more frequently in astrocyte somata, processes, and perivascular regions of 5xFAD mice. However, evoked arteriole dilations (in …

Parallel Electrophysiological Abnormalities Due To Covid-19 Infection And To Alzheimer’S Disease And Related Dementia, Yang Jiang, Jennifer Neal, Pradoldej Sompol, Görsev Yener, Xianghong Arakaki, Christopher M. Norris, Francesca R. Farina, Agustin Ibanez, Susanna Lopez, Abdulhakim Al-Ezzi, Voyko Kavcic, Bahar Güntekin, Claudio Babiloni, Mihály Hajós

Neurology Faculty Publications

Many coronavirus disease 2019 (COVID-19) positive individuals exhibit abnormal electroencephalographic (EEG) activity reflecting “brain fog” and mild cognitive impairments even months after the acute phase of infection. Resting-state EEG abnormalities include EEG slowing (reduced alpha rhythm; increased slow waves) and epileptiform activity. An expert panel conducted a systematic review to present compelling evidence that cognitive deficits due to COVID-19 and to Alzheimer’s disease and related dementia (ADRD) are driven by overlapping pathologies and neurophysiological abnormalities. EEG abnormalities seen in COVID-19 patients resemble those observed in early stages of neurodegenerative diseases, particularly ADRD. It is proposed that similar EEG abnormalities in …

Cerebrovascular Disease Is Associated With Alzheimer's Plasma Biomarker Concentrations In Adults With Down Syndrome, Andreas Engvig, Karl Trygve Kalleberg, Lars T. Westlye, Esten Høyland Leonardsen, Alzheimer’S Disease Neuroimaging Initiative Consortium

Neurology Faculty Publications

DNA methylation age (MA), brain age (BA), and frailty index (FI) are putative aging biomarkers linked to dementia risk. We investigated their relationship and combined potential for prediction of cognitive impairment and future dementia risk using the ADNI database. Of several MA algorithms, DunedinPACE and GrimAge2, associated with memory, were combined in a composite MA alongside BA and a data-driven FI in predictive analyses. Pairwise correlations between age- and sex-adjusted measures for MA (aMA), aBA, and aFI were low. FI outperformed BA and MA in all diagnostic tasks. A model including age, sex, and aFI achieved an area under the …

Cerebrovascular Reactivity Mri As A Biomarker For Cerebral Small Vessel Disease–Related Cognitive Decline: Multi-Site Validation In The Markvcid Consortium, Peiying Liu, Zixuan Lin, Kaisha Hazel, George Pottanat, Cuimei Xu, Dengrong Jiang, Jay J. Pillai, Emma Lucke, Christopher E. Bauer, Brian T. Gold, Steven M. Greenburg, Karl G. Helmer, Kay Jann, Gregory Jicha, Joel Kramer, Pauline Maillard, Rachel M. Mulavelil, Pavel Rodriguez, Claudia L. Satizabal, Kristin Schwab, Sudha Seshadri, Herpreet Singh, Ángel G. Velarde Dediós, Danny J. J. Wang, Rita R. Kalyani, Abhay Moghekar, Paul B. Rosenberg, Sevil Yasar, Marilyn Albert, Hanzhang Lu

Neurology Faculty Publications

INTRODUCTION: Vascular contributions to cognitive impairment and dementia (VCID) represent a major factor in cognitive decline in older adults. The present study examined the relationship between cerebrovascular reactivity (CVR) measured by magnetic resonance imaging (MRI) and cognitive function in a multi-site study, using a predefined hypothesis.

METHODS: We conducted the study in a total of three analysis sites and 263 subjects. Each site performed an identical CVR MRI procedure using 5% carbon dioxide inhalation. A global cognitive measure of Montreal Cognitive Assessment (MoCA) and an executive function measure of item response theory (IRT) score were used as outcomes.

RESULTS: CVR …

Decentralized Clinical Trials For Medications To Reduce The Risk Of Dementia: Consensus Report And Guidance, Leanne Howard, Carla Abdelnour, Erin Abner, Ricardo F. Allegri, Hiroko H. Dodge, Serge Gauthier, Camilla M. Hoyos, Gregory Jicha, Patrick G. Kehoe, Catherine J. Mummery, Adesola Ogunniyi, Nikolaos Scarmeas, Xiaoying Chen, Jodie R. Titiner, Christopher R. Weber, Ruth Peters

Neurology Faculty Publications

INTRODUCTION: Recent growth in the functionality and use of technology has prompted an increased interest in the potential for remote or decentralized clinical trials in dementia. There are many potential benefits associated with decentralized medication trials, but we currently lack specific recommendations for their delivery in the dementia field.

METHODS: A modified Delphi method engaged an expert panel to develop recommendations for the conduct of decentralized medication trials in dementia prevention. A working group of researchers and clinicians with expertise in dementia trials further refined the recommendations.

RESULTS: Overall, the recommendations support the delivery of decentralized trials in dementia prevention …

Estrogen’S Sex-Specific Effects On Ischemic Cell Death And Estrogen Receptor Mrna Expression In Rat Cortical Organotypic Explants, Amanda L. Trout, Christopher J. Mclouth, Jenna Westberry, Tomoko Sengoku, Melinda E. Wilson

Neurology Faculty Publications

Estrogens, such as the biologically active 17-β estradiol (E2), regulate not only reproductive behaviors in adults, but also influence neurodevelopment and neuroprotection in both females and males. E2, contingent upon the timing and concentration of the therapy, is neuroprotective in female and male rodent models of stroke. In Vivo studies suggest that E2 may partially mediate this neuroprotection, particularly in the cortex, via ERα. In Vitro studies, utilizing a chemically induced ischemic injury in cortical explants from both sexes, suggest that ERα or ERβ signaling is needed to mediate the E2 protection. Since we know that the timing and concentration …

Different Cohort, Disparate Results: Selection Bias Is A Key Factor In Autopsy Cohorts, Kathryn Gauthreaux, Walter A. Kukull, Karin B. Nelson, Charles Mock, Yen-Chi Chen, Kwun C. G. Chan, David W. Fardo, Yuriko Katsumata, Erin L. Abner, Peter T. Nelson

Neurology Faculty Publications

INTRODUCTION: Research-oriented autopsy cohorts provide critical insights into dementia pathobiology. However, different studies sometimes report disparate findings, partially because each study has its own recruitment biases. We hypothesized that a straightforward metric, related to the percentage of research volunteers cognitively normal at recruitment, would predict other inter-cohort differences.

METHODS: The National Alzheimer’s Coordinating Center (NACC) provided data on N = 7178 autopsied participants from 28 individual research centers. Research cohorts were grouped based on the proportion of participants with normal cognition at initial clinical visit.

RESULTS: Cohorts with more participants who were cognitively normal at recruitment contained more individuals who …

Mechanisms Of Γδ T Cell Accumulation In Visceral Adipose Tissue With Aging, Sujata Mukherjee, Maria E. C. Bruno, Jason Oakes, Gregory S. Hawk, Arnold Stromberg, Donald A. Cohen, Marlene E. Starr

Markey Cancer Center Faculty Publications

γδ T cells are resident in visceral adipose tissue (VAT) where they show an age- associated increase in numbers and contribute to local and systemic chronic inflammation. However, regulation of this population and mechanisms for the age-dependent accumulation are not known. In this study, we identified a progressive trend of γδ T cell accumulation in VAT over the lifespan in mice and explored physiological mechanisms contributing to accumulation. Using isochronic parabiotic pairs of wild-type (WT) and T cell receptor delta knockout (TCRδ KO) mice at young and old age, we confirmed that VAT γδ T cells are predominately a tissue-resident …

Making Home: The Role Of Social Networks On Identity, Health, And Quality Of Life Among Rural Lesbian And Gay Older Adults, Marc A. Guest, Elizabeth G. Hunter, Nancy E. Schoenberg

UK CARES Faculty Publications

Background and Objectives: Gay and lesbian older persons face a host of health inequalities related to their identity as they age. Challenges to health access and appropriate social support may be even more exacerbated for those living in rural environments; this may be due to the lack of supportive and affirming social connections. This project aimed to explore and describe the social networks and the relationship of these social networks to identity, health, and quality of life of gay and lesbian individuals in rural communities.

Research Design and Methods: Social network data on network type, size, and social capital were …

Rna Editing Of Microtubule-Associated Protein Tau Circular Rnas Promotes Their Translation And Tau Tangle Formation, Justin Ralph Welden, Giorgi Margvelani, Karol Andrea Arizaca Maquera, Bhavani Gudlavalleti, Sandra C. Miranda Sardón, Alexandre Rosa Campos, Noémie Robil, Daniel C. Lee, Alvaro G. Hernandez, Wang-Xia Wang, Jing Di, Pierre De La Grange, Peter T. Nelson, Stefan Stamm

Sanders-Brown Center on Aging Faculty Publications

Aggregation of the microtubule-associated protein tau characterizes tauopathies, including Alzheimer’s disease and frontotemporal lobar degeneration (FTLD-Tau). Gene expression regulation of tau is complex and incompletely understood. Here we report that the human tau gene (MAPT) generates two circular RNAs (circRNAs) through backsplicing of exon 12 to either exon 7 (12→7 circRNA) or exon 10 (12→10 circRNA). Both circRNAs lack stop codons. The 12→7 circRNA contains one start codon and is translated in a rolling circle, generating a protein consisting of multimers of the microtubule-binding repeats R1–R4. For the 12→10 circRNA, a start codon can be introduced by two …

Genetic Expression Changes And Pathologic Findings Associated With Hyperhomocysteinemia In Human Autopsy Brain Tissue, Erica M. Weekman, Zachary Winder, Colin B. Rogers, Erin L. Abner, Tiffany L. Sudduth, Ela Patel, Adam J. Dugan, Shuling X. Fister, Brandi Wasek, Peter T. Nelson, Gregory A. Jicha, Teodoro Bottiglieri, David W. Fardo, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Introduction: Vascular contributions to cognitive impairment and dementia (VCID) are a leading cause of dementia. An underappreciated, modifiable risk factor for VCID is hyperhomocysteinemia (HHcy), defined by elevated levels of plasma homocysteine, most often due to impaired B vitamin absorption in aged persons. Studies aimed at identifying neuropathologic features and gene expression profiles associated with HHcy have been lacking.

Methods: A subset of research volunteers from the University of Kentucky Alzheimer’s Disease Research Center longitudinal cohort came to autopsy and had ante mortem plasma homocysteine levels available. Brain tissue and blood plasma drawn closest to death were used to measure …

Apoe Genetics Influence Murine Gut Microbiome, Diana J. Zajac, Stefan J. Green, Lance A. Johnson, Steven Estus

Sanders-Brown Center on Aging Faculty Publications

Apolipoprotein E (APOE) alleles impact pathogenesis and risk for multiple human diseases, making them primary targets for disease treatment and prevention. Previously, we and others reported an association between APOE alleles and the gut microbiome. Here, we evaluated effects of APOE heterozygosity and tested whether these overall results extended to mice maintained under ideal conditions for microbiome analyses. To model human APOE alleles, this study used APOE targeted replacement (TR) mice on a C57Bl/6 background. To minimize genetic drift, homozygous APOE3 mice were crossed to homozygous APOE2 or homozygous APOE4 mice prior to the study, and the resulting …

Single Low-Dose Targeted Bevacizumab Infusion In Adult Patients With Steroid-Refractory Radiation Necrosis Of The Brain: A Phase Ii Open-Label Prospective Clinical Trial, Shervin R. Dashti, Robert J. Kadner, Bradley S. Folley, Jason P. Sheehan, Dong Y. Han, Richard J. Kryscio, Mary B. Carter, Lisa B. E. Shields, Brian M. Plato, Renato V. La Rocca, Aaron C. Spalding, Tom L. Yao, Justin F. Fraser

Sanders-Brown Center on Aging Faculty Publications

OBJECTIVE There is an unmet need for safe and rapidly effective therapies for refractory brain radiation necrosis (RN). The aim of this prospective single-arm phase II trial was to evaluate the safety and efficacy of a single low-dose targeted bevacizumab infusion after blood-brain barrier disruption (BBBD) in adult patients with steroid-refractory brain RN.

METHODS Ten adults with steroid-refractory, imaging-confirmed brain RN were enrolled between November 2016 and January 2018 and followed for 12 months after treatment. Bevacizumab 2.5 mg/kg was administered as a one-time targeted intra-arterial infusion immediately after BBBD. Primary outcomes included safety and > 25% decrease in lesion volume. …

The Association Of Gabapentin Initiation And Neurocognitive Changes In Older Adults With Normal Cognition, Gyeon Oh, Daniela Claudia Moga, David W. Fardo, Erin L. Abner

Sanders-Brown Center on Aging Faculty Publications

Background: Gabapentin is increasingly prescribed to older adults, which raises concerns about its potential to cause neurocognitive changes. Therefore, we aimed to examine the association of gabapentin use with neurocognitive changes (i.e., cognitive decline, functional status decline, and motor function change) in older adults.

Methods: We conducted a retrospective cohort study using the National Alzheimer’s Coordinating Center Uniform Data Set (UDS; September 2005-March 2021 data freeze). From the eligible sample (≥age 65 years), we identified cognitively normal new-users of gabapentin and the visit they initiated gabapentin (i.e., index visit). Initiators were matched to randomly selected nonusers on year …

Deep Learning Algorithm Reveals Probabilities Of Stage-Specific Time To Conversion In Individuals With Neurodegenerative Disease Late, Xinxing Wu, Chong Peng, Peter T. Nelson, Qiang Cheng

Sanders-Brown Center on Aging Faculty Publications

Introduction: Limbic-predominant age-related TAR DNA-binding protein 43 (TDP-43) encephalopathy (LATE) is a recently defined neurodegenerative disease. Currently, there is no effective way to make a prognosis of time to stage-specific future conversions at an individual level.

Methods: After using the Kaplan–Meier estimation and log-rank test to confirm the heterogeneity of LATE progression, we developed a deep learning–based approach to assess the stage-specific probabilities of time to LATE conversions for different subjects.

Results: Our approach could accurately estimate the disease incidence and transition to next stages: the concordance index was at least 82% and the integrated Brier score …

Examining The Effects Of Formal Education Level On The Montreal Cognitive Assessment, Renee S. White, Justin M. Barber, Jordan P. Harp, Gregory A. Jicha

Sanders-Brown Center on Aging Faculty Publications

Background: Brief, global assessments such as the Montreal Cognitive Assessment (MoCA) are widely used in primary care for assessing cognition in older adults. Like other neuropsychological instruments, lower formal education can influence MoCA interpretation.

Methods: Data from 2 large studies of cognitive aging were used—Alzheimer’s Disease Neuroimaging Initiative (ADNI) and National Alzheimer’s Coordinating Center (NACC). Both use comprehensive examinations to determine cognitive status and have brain amyloid status for many participants. Mixed models were used to account for random variation due to data source.

Results: Cognitively intact participants with lower education (≤12 years) were more likely than …

Multiple Gene Variants Linked To Alzheimer's-Type Clinical Dementia Via Gwas Are Also Associated With Non-Alzheimer's Neuropathologic Entities, Yuriko Katsumata, Lincoln M. P. Shade, Timothy J. Hohman, Julie A. Schneider, David A. Bennett, Jose M. Farfel, Walter A. Kukull, David W. Fardo, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

The classic pathologic hallmarks of Alzheimer’s disease (AD) are amyloid plaques and neurofibrillary tangles (AD neuropathologic changes, or ADNC). However, brains from individuals clinically diagnosed with “AD-type” (amnestic) dementia usually harbor heterogeneous neuropathologies in addition to, or other than, ADNC. We hypothesized that some AD-type dementia associated genetic single nucleotide variants (SNVs) identified from large genomewide association studies (GWAS) were associated with non-ADNC neuropathologies. To test this hypothesis, we analyzed data from multiple studies with available genotype and neuropathologic phenotype information. Clinical AD/dementia risk alleles of interest were derived from the very large GWAS by Bellenguez et al. (2022) who …

Role Of Sympathetic Pathway In Light-Phase Time-Restricted Feeding-Induced Blood Pressure Circadian Rhythm Alteration, Tianfei Hou, Aaron Chacon, Wen Su, Yuriko Katsumata, Zhenheng Guo, Ming Gong

Sanders-Brown Center on Aging Faculty Publications

Disruption of blood pressure (BP) circadian rhythm, independent of hypertension, is emerging as an index for future target organ damage and is associated with a higher risk of cardiovascular events. Previous studies showed that changing food availability time alters BP rhythm in several mammalian species. However, the underlying mechanisms remain largely unknown. To address this, the current study specifically investigates (1) the relationship between rhythms of food intake and BP in wild-type mice; (2) effects of light-phase time-restricted feeding (TRF, food only available during light-phase) on BP circadian rhythm in wild-type and diabetic db/db mice; (3) the roles of the …

The Trend Of Disruption In The Functional Brain Network Topology Of Alzheimer’S Disease, Alireza Fathian, Yousef Jamali, Mohammad Reza Raoufy, The Alzheimer's Disease Neuroimaging Initiative, Michael W. Weiner, Norbert Schuf, Howard J. Rosen, Bruce L. Miller, Thomas Neylan, Jacqueline Hayess, Shannon Finley, Paul Aisen, Zaven Khachaturian, Ronald G. Thomas, Charles D. Smith, Gregory A. Jicha, Peter A. Hardy, Partha Sinha, Elizabeth Oates, Gary Conrad

Sanders-Brown Center on Aging Faculty Publications

Alzheimer’s disease (AD) is a progressive disorder associated with cognitive dysfunction that alters the brain’s functional connectivity. Assessing these alterations has become a topic of increasing interest. However, a few studies have examined different stages of AD from a complex network perspective that cover different topological scales. This study used resting state fMRI data to analyze the trend of functional connectivity alterations from a cognitively normal (CN) state through early and late mild cognitive impairment (EMCI and LMCI) and to Alzheimer’s disease. The analyses had been done at the local (hubs and activated links and areas), meso (clustering, assortativity, and …