Geriatrics Commons^™

Manganese-Enhanced Magnetic Resonance Imaging: Overview And Central Nervous System Applications With A Focus On Neurodegeneration, Ryan A. Cloyd, Shon A. Koren, Jose F. Abisambra

Physiology Faculty Publications

Manganese-enhanced magnetic resonance imaging (MEMRI) rose to prominence in the 1990s as a sensitive approach to high contrast imaging. Following the discovery of manganese conductance through calcium-permeable channels, MEMRI applications expanded to include functional imaging in the central nervous system (CNS) and other body systems. MEMRI has since been employed in the investigation of physiology in many animal models and in humans. Here, we review historical perspectives that follow the evolution of applied MRI research into MEMRI with particular focus on its potential toxicity. Furthermore, we discuss the more current in vivo investigative uses of MEMRI in CNS investigations and …

Pharmacy Staff Perspectives On Alcohol And Medication Interaction Prevention Among Older Rural Adults, Faika Zanjani, Hannah Allen, Rachel Vickers Smith, Demetra Antimisiaris, Nancy E. Schoenberg, Catherine A. Martin, Richard Clayton

Behavioral Science Faculty Publications

Older adults are at high risk for alcohol and medication interactions (AMI). Pharmacies have the potential to act as ideal locations for AMI education, as pharmacy staff play an important role in the community. This study examined the perspectives of pharmacy staff on AMI prevention programming messaging, potential barriers to and facilitators of older adult participation in such programming, and dissemination methods for AMI prevention information. Flyers, telephone calls, and site visits were used to recruit 31 pharmacy staff members who participated in semistructured interviews. A content analysis of interview transcriptions was conducted to identify major themes, categories, and subcategories. …

Distinct White Matter Changes Associated With Cerebrospinal Fluid Amyloid-Β1-42 And Hypertension, Omar M. Al-Janabi, Christopher A. Brown, Ahmed A. Bahrani, Erin L. Abner, Justin M. Barber, Brian T. Gold, Larry B. Goldstein, Richard R. Murphy, Peter T. Nelson, Nathan F. Johnson, Leslie M. Shaw, Charles D. Smith, John Q. Trojanowski, Donna M. Wilcock, Gregory A. Jicha

Sanders-Brown Center on Aging Faculty Publications

BACKGROUND: Alzheimer's disease (AD) pathology and hypertension (HTN) are risk factors for development of white matter (WM) alterations and might be independently associated with these alterations in older adults.

OBJECTIVE: To evaluate the independent and synergistic effects of HTN and AD pathology on WM alterations.

METHODS: Clinical measures of cerebrovascular disease risk were collected from 62 participants in University of Kentucky Alzheimer's Disease Center studies who also had cerebrospinal fluid (CSF) sampling and MRI brain scans. CSF Aβ_1-42 levels were measured as a marker of AD, and fluid-attenuated inversion recovery imaging and diffusion tensor imaging were obtained to assess …

Hyperhomocysteinemia As A Risk Factor For Vascular Contributions To Cognitive Impairment And Dementia, Brittani R. Price, Donna M. Wilcock, Erica M. Weekman

Physiology Faculty Publications

Behind only Alzheimer’s disease, vascular contributions to cognitive impairment and dementia (VCID) is the second most common cause of dementia, affecting roughly 10–40% of dementia patients. While there is no cure for VCID, several risk factors for VCID, such as diabetes, hypertension, and stroke, have been identified. Elevated plasma levels of homocysteine, termed hyperhomocysteinemia (HHcy), are a major, yet underrecognized, risk factor for VCID. B vitamin deficiency, which is the most common cause of HHcy, is common in the elderly. With B vitamin supplementation being a relatively safe and inexpensive therapeutic, the treatment of HHcy-induced VCID would seem straightforward; however, …

Glimepiride Administered In Chow Reversibly Impairs Glucose Tolerance In Mice, Dana M. Niedowicz, Sabire Özcan, Peter T. Nelson

Sanders-Brown Center on Aging Faculty Publications

Sulfonylureas are a class of antidiabetes medications prescribed to millions of individuals worldwide. Rodents have been used extensively to study sulfonylureas in the laboratory. Here, we report the results of studies treating mice with a sulfonylurea (glimepiride) in order to understand how the drug affects glucose homeostasis and tolerance. We tested the effect of glimepiride on fasting blood glucose, glucose tolerance, and insulin secretion, using glimepiride sourced from a local pharmacy. We also examined the effect on glucagon, gluconeogenesis, and insulin sensitivity. Unexpectedly, glimepiride exposure in mice was associated with fasting hyperglycemia, glucose intolerance, and decreased insulin. There was no …

Octo- And Nonagenarians' Outlook On Life And Death When Living With An Implantable Cardioverter Defibrillator: A Cross-Sectional Survey, Ingela Thylén, Debra K. Moser, Anna Strömberg

Nursing Faculty Publications

Background: Elderly individuals are increasingly represented among patients with implantable cardioverter defibrillators (ICD), but data describing life with an ICD are scarse among octo- and nonagenarians. Moreover, few studies have reported those elderly patients’ perspective on timly discussions concerning what shock deactivation involves, preferences on battery replacement, and their attitudes about turning off the ICD nearing end-of-life. Consequently, the aim of the study was to describe outlooks on life and death in octo- and nonagenarian ICD-recipients.

Methods: Participants were identified via the Swedish Pacemaker- and ICD-registry, with 229 octo- and nonagenarians (82.0 ± 2.2 years, 12% female) completing the survey …

P-21 Activated Kinase As A Molecular Target For Chemoprevention In Diabetes, Kyle Dammann, Vineeta Khare, Clyde Coleman, Henrik Berdel, Christoph Gasche

Surgery Faculty Publications

Hypothesis: Anti-diabetic drugs modulate p-21 activated kinase (PAK) signaling. Introduction: Type 2 diabetes mellitus (T2DM) is a chronic inflammatory disease associated with increased cancer risk. PAK signaling is implicated in cellular homeostasis when regulated, and cancer when unrestrained. Recent reports provided a role for PAK signaling in glucose homeostasis, but the role of PAKs in the pathogenesis of T2DM is unknown. Here, we performed a mini-meta-analysis to explore if anti-diabetic drugs modify PAK signaling pathways, and provide insight regarding modulation of these pathways, to potentially reduce diabetes-associated cancer risk. Methods: PAK interacting partners in T2DM were identified using the online …

Astrocyte Activation And The Calcineurin/Nfat Pathway In Cerebrovascular Disease, Susan D. Kraner, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

Calcineurin (CN) is a Ca²⁺/calmodulin-dependent protein phosphatase with high abundance in nervous tissue. Though enriched in neurons, CN can become strongly induced in subsets of activated astrocytes under different pathological conditions where it interacts extensively with the nuclear factor of activated T cells (NFATs). Recent work has shown that regions of small vessel damage are associated with the upregulation of a proteolized, highly active form of CN in nearby astrocytes, suggesting a link between the CN/NFAT pathway and chronic cerebrovascular disease. In this Mini Review article, we discuss CN/NFAT signaling properties in the context of vascular disease and …

Isolation Of Cerebral Capillaries From Fresh Human Brain Tissue, Anika M. S. Hartz, Julia A. Schulz, Brent S. Sokola, Stephanie E. Edelmann, Andrew N. Shen, Ralf G. Rempe, Yu Zhong, Nader El Seblani, Bjoern Bauer

Sanders-Brown Center on Aging Faculty Publications

Understanding blood-brain barrier function under physiological and pathophysiological conditions is critical for the development of new therapeutic strategies that hold the promise to enhance brain drug delivery, improve brain protection, and treat brain disorders. However, studying the human blood-brain barrier function is challenging. Thus, there is a critical need for appropriate models. In this regard, brain capillaries isolated from human brain tissue represent a unique tool to study barrier function as close to the human in vivo situation as possible. Here, we describe an optimized protocol to isolate capillaries from human brain tissue at a high yield and with consistent …

In Vivo Brainstem Imaging In Alzheimer’S Disease: Potential For Biomarker Development, David J. Braun, Linda J. Van Eldik

Neuroscience Faculty Publications

The dearth of effective treatments for Alzheimer’s disease (AD) is one of the largest public health issues worldwide, costing hundreds of billions of dollars per year. From a therapeutic standpoint, research efforts to date have met with strikingly little clinical success. One major issue is that trials begin after substantial pathological change has occurred, and it is increasingly clear that the most effective treatment regimens will need to be administered earlier in the disease process. In order to identify individuals within the long preclinical phase of AD who are likely to progress to dementia, improvements are required in biomarker development. …

Prognostic Factors For Elderly Patients Treated With Stereotactic Body Radiation Therapy For Pancreatic Adenocarcinoma, Philip A. Sutera, Mark E. Bernard, Hong Wang, Dwight E. Heron

Radiation Medicine Faculty Publications

Introduction: Pancreatic ductal adenocarcinoma (PDAC) commonly presents later in life with a median age at diagnosis of 70 years. Unfortunately, elderly patients are significantly underrepresented in clinical trials. Stereotactic body radiation therapy (SBRT) is a promising treatment modality in this population as it has demonstrated excellent local control with minimal toxicity. We aimed to determine prognostic factors associated with outcomes in elderly patients treated with SBRT.

Materials and Methods: Elderly patients older than 70 treated with SBRT for PDAC at our institution, from 2004 to 2014 were included. Our primary endpoints included overall survival (OS) and local-progression-free survival (LPFS). Secondary …

Neuroimaging Biomarkers Of Mtor Inhibition On Vascular And Metabolic Functions In Aging Brain And Alzheimer’S Disease, Jennifer Lee, Lucille M. Yanckello, David Ma, Jared D. Hoffman, Ishita Parikh, Scott Thalman, Bjoern Bauer, Anika M. S. Hartz, Fahmeed Hyder, Ai-Ling Lin

Pharmacology and Nutritional Sciences Faculty Publications

The mechanistic target of rapamycin (mTOR) is a nutrient sensor of eukaryotic cells. Inhibition of mechanistic mTOR signaling can increase life and health span in various species via interventions that include rapamycin and caloric restriction (CR). In the central nervous system, mTOR inhibition demonstrates neuroprotective patterns in aging and Alzheimer’s disease (AD) by preserving mitochondrial function and reducing amyloid beta retention. However, the effects of mTOR inhibition for in vivo brain physiology remain largely unknown. Here, we review recent findings of in vivo metabolic and vascular measures using non-invasive, multimodal neuroimaging methods in rodent models for brain aging and AD. …

Ca2+, Astrocyte Activation And Calcineurin/Nfat Signaling In Age-Related Neurodegenerative Diseases, Pradoldej Sompol, Christopher M. Norris

Sanders-Brown Center on Aging Faculty Publications

Mounting evidence supports a fundamental role for Ca²⁺ dysregulation in astrocyte activation. Though the activated astrocyte phenotype is complex, cell-type targeting approaches have revealed a number of detrimental roles of activated astrocytes involving neuroinflammation, release of synaptotoxic factors and loss of glutamate regulation. Work from our lab and others has suggested that the Ca²⁺/calmodulin dependent protein phosphatase, calcineurin (CN), provides a critical link between Ca²⁺ dysregulation and the activated astrocyte phenotype. A proteolyzed, hyperactivated form of CN appears at high levels in activated astrocytes in both human tissue and rodent tissue around regions of amyloid and …

Microrna Expression Patterns In Human Anterior Cingulate And Motor Cortex: A Study Of Dementia With Lewy Bodies Cases And Controls, Peter T. Nelson, Wang-Xia Wang, Sarah A. Janse, Katherine L. Thompson

Sanders-Brown Center on Aging Faculty Publications

Overview

MicroRNAs (miRNAs) have been implicated in neurodegenerative diseases including Parkinson’s disease and Alzheimer’s disease (AD). Here, we evaluated the expression of miRNAs in anterior cingulate (AC; Brodmann area [BA] 24) and primary motor (MO; BA 4) cortical tissue from aged human brains in the University of Kentucky AD Center autopsy cohort, with a focus on dementia with Lewy bodies (DLB).

Methods

RNA was isolated from gray matter of brain samples with pathology-defined DLB, AD, AD+DLB, and low-pathology controls, with n=52 cases initially included (n=23 with DLB), all with low (<4hrs) postmortem intervals. RNA was profiled using Exiqon miRNA microarrays. Quantitative PCR for post-hoc replication was performed on separate cases (n=6 controls) and included RNA isolated from gray matter of MO, AC, primary somatosensory (BA 3), and dorsolateral prefrontal (BA 9) cortical regions.

Results

The miRNA expression patterns differed substantially according to …

Intra-Arterial Nitroglycerin As Directed Acute Treatment In Experimental Ischemic Stroke, Michael E. Maniskas, Jill M. Roberts, Rebecca Trueman, Annastazia E. Learoyd, Amanda A. Gorman, Justin F. Fraser, Gregory J. Bix

Neuroscience Faculty Publications

BACKGROUND: Nitroglycerin (also known as glyceryl trinitrate (GTN)), a vasodilator best known for treatment of ischemic heart disease, has also been investigated for its potential therapeutic benefit in ischemic stroke. The completed Efficacy of Nitric Oxide in Stroke trial suggested that GTN has therapeutic benefit with acute (within 6 hours) transdermal systemic sustained release therapy.

OBJECTIVE: To examine an alternative use of GTN as an acute therapy for ischemic stroke following successful recanalization.

METHODS: We administered GTN IA following transient middle cerebral artery occlusion in mice. Because no standard dose of GTN is available following emergent large vessel occlusion, we …