Digital Commons Network^™

Methamphetamine Administration Targets Multiple Immune Subsets And Induces Phenotypic Alterations Suggestive Of Immunosuppression., Robert Z. Harms, Brenda M. Morsey, Craig W. Boyer, Howard S. Fox, Nora E. Sarvetnick

Journal Articles: Regenerative Medicine

Methamphetamine (Meth) is a widely abused stimulant and its users are at increased risk for multiple infectious diseases. To determine the impact of meth on the immune system, we utilized a murine model that simulates the process of meth consumption in a typical addict. Our phenotypic analysis of leukocytes from this dose escalation model revealed that meth affected key immune subsets. Meth administration led to a decrease in abundance of natural killer (NK) cells and the remaining NK cells possessed a phenotype suggesting reduced responsiveness. Dendritic cells (DCs) and Gr-1(high) monocytes/macrophages were also decreased in abundance while Gr-1(low) monocytes/macrophages appear …

Cellular Retrograde Cardiomyoplasty And Relaxin Therapy For Postischemic Myocardial Repair In A Rat Model, Gabriella Di Lascio, Guy Harmelin, Mattia Targetti, Cristina Nanni, Giacomo Bianchi, Tommaso Gasbarri, Sandro Gelsomino, Daniele Bani, Sandra Zecchi Orlandini, Massimo Bonacchi

The Texas Heart Institute Journal

We sought to determine whether skeletal myoblasts, wild-type or engineered to express relaxin, might improve myocardial viability and performance in a rat model of chronic myocardial infarction. Our purpose was to investigate a potential new therapy for heart failure.

From October 2005 through September 2009, we surgically induced acute myocardial infarction in 80 male Wistar rats. Thirty days after surgery, the rats underwent reoperation for the retrograde coronary venous infusion of skeletal myoblasts, relaxin, or both. The animals were randomly assigned to 4 experimental groups: R1 (the control group, which underwent saline-solution infusion), R2 (systemic relaxin therapy), R3 (myoblast infusion), …

Does The Expression Of Transforming Growth Factor Β-1: Affect The Outcome Of The Radiofrequency Modified Maze Procedure In Patients With Rheumatic Atrial Fibrillation?, Wei Wang, Lei Liu, Yuan Li, Sheng-Shou Hu, Yun-Hu Song, Xin Wang

The Texas Heart Institute Journal

We investigated whether the expression of transforming growth factor β-1 in the left atrial appendage affected the outcome of the radiofrequency modified maze procedure in patients with rheumatic valve disease and long-standing persistent atrial fibrillation.

Messenger RNA and protein expression of transforming growth factor β-1 and volume fractions of collagen types I and III were measured in 80 patients with rheumatic valve atrial fibrillation who underwent valve surgery with the radiofrequency modified maze procedure; the same was done in a control group of 20 patients with rheumatic valve disease and sinus rhythm who underwent valve surgery alone.

At 6 months' …

Triterpenoid Modulation Of Il-17 And Nrf-2 Expression Ameliorates Neuroinflammation And Promotes Remyelination In Autoimmune Encephalomyelitis, Tej K. Pareek, Abdelmadjid Belkadi, Sashi Kesavapany, Anita Zaremba, Sook L. Loh, Lianhua Bai, Mark L. Cohen, Colin Meyer, Karen T. Liby, Robert H. Miller, Michael B. Sporn, John J. Letterio

Dartmouth Scholarship

Inflammatory cytokines and endogenous anti-oxidants are variables affecting disease progression in multiple sclerosis (MS). Here we demonstrate the dual capacity of triterpenoids to simultaneously repress production of IL-17 and other pro-inflammatory mediators while exerting neuroprotective effects directly through Nrf2-dependent induction of anti-oxidant genes. Derivatives of the natural triterpene oleanolic acid, namely CDDO-trifluoroethyl-amide (CDDO-TFEA), completely suppressed disease in a murine model of MS, experimental autoimmune encephalomyelitis (EAE), by inhibiting Th1 and Th17 mRNA and cytokine production. Encephalitogenic T cells recovered from treated mice were hypo-responsive to myelin antigen and failed to adoptively transfer the disease. Microarray analyses showed significant suppression of …

Wnt Signaling Exerts An Antiproliferative Effect On Adult Cardiac Progenitor Cells Through Igfbp3., Angelos Oikonomopoulos, Konstantina-Ioanna Sereti, Frank Conyers, Michael Bauer, Annette Liao, Jian Guan, Dylan Crapps, Jung-Kyu Han, Hanhua Dong, Ahmad F Bayomy, Gabriel C Fine, Karen Westerman, Travis L Biechele, Randall T Moon, Thomas Force, Ronglih Liao

Center for Translational Medicine Faculty Papers

RATIONALE: Recent work in animal models and humans has demonstrated the presence of organ-specific progenitor cells required for the regenerative capacity of the adult heart. In response to tissue injury, progenitor cells differentiate into specialized cells, while their numbers are maintained through mechanisms of self-renewal. The molecular cues that dictate the self-renewal of adult progenitor cells in the heart, however, remain unclear.

OBJECTIVE: We investigate the role of canonical Wnt signaling on adult cardiac side population (CSP) cells under physiological and disease conditions.

METHODS AND RESULTS: CSP cells isolated from C57BL/6J mice were used to study the effects of canonical …

Effects Of Prenatal Food And Micronutrient Supplementation On Child Growth From Birth To 54 Months Of Age: A Randomized Trial In Bangladesh, Ashraful Islam Khan, Iqbal Kabir, Eva-Charlotte Ekström, Kajsa Åsling-Monemi, Dewan Shamsul Alam, Edward A. Frongillo Jr., Md Yunus, Shams Arifeen, Lars-Åke Persson

Faculty Publications

Background: There is a lack of information on the optimal timing of food supplementation to malnourished pregnant women and possible combined effects of food and multiple micronutrient supplementations (MMS) on their offspring's growth. We evaluated the effects of prenatal food and micronutrient interventions on postnatal child growth. The hypothesis was that prenatal MMS and early invitation to food supplementation would increase physical growth in the offspring during 0-54 months and a combination of these interventions would further improve these outcomes.

Methods: In the large, randomized MINIMat trial (Maternal and Infant Nutrition Interventions in Matlab), Bangladesh, 4436 pregnant women were enrolled …

Histone Deacetylase Inhibitor Valproic Acid Suppresses The Growth And Increases The Androgen Responsiveness Of Prostate Cancer Cells., Yu-Wei Chou, Nagendra K. Chaturvedi, Shougiang Ouyang, Fen-Fen Lin, Dharam Kaushik, Jue Wang, Isaac Kim, Ming-Fong Lin

Journal Articles: Biochemistry & Molecular Biology

We identified the molecular target by histone deacetylase (HDAC) inhibitors for exploring their potential prostate cancer (PCa) therapy. Upon HDAC inhibitors-treatment, LNCaP cell growth was suppressed, correlating with increased cellular prostatic acid phosphatase (cPAcP) expression, an authentic protein tyrosine phosphatase. In those cells, ErbB-2 was dephosphorylated, histone H3/H4 acetylation and methylation increased and cyclin proteins decreased. In PAcP shRNA-transfected C-81 cells, valproic acid (VPA) efficacy of growth suppression was diminished. Further, VPA pre-treatment enhanced androgen responsiveness of C-81, C4-2 and MDA PCa2b-AI cells. Thus, cPAcP expression is involved in growth suppression by HDAC inhibitors in PCa cells, and VPA pre-treatments …

Specific Contributions Of Ventromedial, Anterior Cingulate, And Lateral Prefrontal Cortex For Attentional Selection And Stimulus Valuation., Daniel Kaping, Martin Vinck, R Matthew Hutchison, Stefan Everling, Thilo Womelsdorf

Brain and Mind Institute Researchers' Publications

Attentional control ensures that neuronal processes prioritize the most relevant stimulus in a given environment. Controlling which stimulus is attended thus originates from neurons encoding the relevance of stimuli, i.e. their expected value, in hand with neurons encoding contextual information about stimulus locations, features, and rules that guide the conditional allocation of attention. Here, we examined how these distinct processes are encoded and integrated in macaque prefrontal cortex (PFC) by mapping their functional topographies at the time of attentional stimulus selection. We find confined clusters of neurons in ventromedial PFC (vmPFC) that predominantly convey stimulus valuation information during attention shifts. …

Maternal Separation Affects Dopamine Transporter Function In The Spontaneously Hypertensive Rat: An In Vivo Electrochemical Study, Jacqueline S. Womersley, Jennifer H. Hsieh, Lauriston A. Kellaway, Greg A. Gerhardt, Vivienne A. Russell

Neuroscience Faculty Publications

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder characterised by symptoms of inattention, impulsivity and hyperactivity. The spontaneously hypertensive rat (SHR) is a well-characterised model of this disorder and has been shown to exhibit dopamine dysregulation, one of the hypothesised causes of ADHD. Since stress experienced in the early stages of life can have long-lasting effects on behaviour, it was considered that early life stress may alter development of the dopaminergic system and thereby contribute to the behavioural characteristics of SHR. It was hypothesized that maternal separation would alter dopamine regulation by the transporter (DAT) in ways that distinguish SHR …

Paradoxical Reversal Learning Enhancement By Stress Or Prefrontal Cortical Damage: Rescue With Bdnf., Carolyn Graybeal, Michael Feyder, Emily Schulman, Lisa M Saksida, Timothy J Bussey, Jonathan L Brigman, Andrew Holmes

Brain and Mind Institute Researchers' Publications

Stress affects various forms of cognition. We found that moderate stress enhanced late reversal learning in a mouse touchscreen-based choice task. Ventromedial prefrontal cortex (vmPFC) lesions mimicked the effect of stress, whereas orbitofrontal and dorsolateral striatal lesions impaired reversal. Stress facilitation of reversal was prevented by BDNF infusion into the vmPFC. These findings suggest a mechanism by which stress-induced vmPFC dysfunction disinhibits learning by alternate (for example, striatal) systems.

Age-Associated Disruption Of Molecular Clock Expression In Skeletal Muscle Of The Spontaneously Hypertensive Rat, Mitsunori Miyazaki, Elizabeth Schroder, Stephanie E. Edelmann, Michael E. Hughes, Karl Kornacker, C. William Balke, Karyn A. Esser

Physiology Faculty Publications

It is well known that spontaneously hypertensive rats (SHR) develop muscle pathologies with hypertension and heart failure, though the mechanism remains poorly understood. Woon et al. (2007) linked the circadian clock gene Bmal1 to hypertension and metabolic dysfunction in the SHR. Building on these findings, we compared the expression pattern of several core-clock genes in the gastrocnemius muscle of aged SHR (80 weeks; overt heart failure) compared to aged-matched control WKY strain. Heart failure was associated with marked effects on the expression of Bmal1, Clock and Rora in addition to several non-circadian genes important in regulating skeletal muscle phenotype including …

Culture Medium, Gas Atmosphere And Mapk Inhibition Affect Regulation Of Rna-Binding Protein Targets During Mouse Preimplantation Development., Michele D Calder, Patricia H Watson, Andrew J Watson

Obstetrics & Gynaecology Publications

During oogenesis, mammalian oocytes accumulate maternal mRNAs that support the embryo until embryonic genome activation. RNA-binding proteins (RBP) may regulate the stability and turnover of maternal and embryonic mRNAs. We hypothesised that varying embryo culture conditions, such as culture medium, oxygen tension and MAPK inhibition, affects regulation of RBPs and their targets during preimplantation development. STAU1, ELAVL1, KHSRP and ZFP36 proteins and mRNAs were detected throughout mouse preimplantation development, whereas Elavl2 mRNA decreased after the two-cell stage. Potential target mRNAs of RBP regulation, Gclc, Slc2a1 and Slc7a1 were detected during mouse preimplantation development. Gclc mRNA was significantly elevated in embryos …

A 2-Step Approach To Myeloablative Haploidentical Stem Cell Transplantation: A Phase 1/2 Trial Performed With Optimized T-Cell Dosing., Dolores Gross, Matthew Carabasi, Joanne Filicko-O'Hara, Margaret Kasner, John L Wagner, Beth Colombe, Patricia Cornett Farley, William O'Hara, Phyllis Flomenberg, Maria Werner-Wasik, Janet Brunner, Bijoyesh Mookerjee, Terry Hyslop, Mark Weiss, Neal Flomenberg

Department of Medical Oncology Faculty Papers

Studies of haploidentical hematopoietic stem cell transplantation (HSCT) have identified threshold doses of T cells below which severe GVHD is usually absent. However, little is known regarding optimal T-cell dosing as it relates to engraftment, immune reconstitution, and relapse. To begin to address this question, we developed a 2-step myeloablative approach to haploidentical HSCT in which 27 patients conditioned with total body irradiation (TBI) were given a fixed dose of donor T cells (HSCT step 1), followed by cyclophosphamide (CY) for T-cell tolerization. A CD34-selected HSC product (HSCT step 2) was infused after CY. A dose of 2 × 10(8)/kg …

Elevated Stearoyl-Coa Desaturase In Brains Of Patients With Alzheimer's Disease, Giuseppe Astarita, Kwang-Mook Jung, Vitaly Vasilevko, Nicholas V. Dipatrizio, Sarah K. Martin, David H. Cribbs, Elizabeth Head, Carl W. Cotman, Daniele Piomelli

Sanders-Brown Center on Aging Faculty Publications

The molecular bases of Alzheimer's disease (AD) remain unclear. We used a lipidomic approach to identify lipid abnormalities in the brains of subjects with AD (N = 37) compared to age-matched controls (N = 17). The analyses revealed statistically detectable elevations in levels of non-esterified monounsaturated fatty acids (MUFAs) and mead acid (20:3n-9) in mid-frontal cortex, temporal cortex and hippocampus of AD patients. Further studies showed that brain mRNAs encoding for isoforms of the rate-limiting enzyme in MUFAs biosynthesis, stearoyl-CoA desaturase (SCD-1, SCD-5a and SCD-5b), were elevated in subjects with AD. The monounsaturated/saturated fatty acid ratio ('desaturation index')--displayed a strong …

Thrombospondin1 Deficiency Reduces Obesity-Associated Inflammation And Improves Insulin Sensitivity In A Diet-Induced Obese Mouse Model, Yanzhang Li, Xiaopeng Tong, Courtney Rumala, Kate Clemons, Shuxia Wang

Graduate Center for Nutritional Sciences Faculty Publications

BACKGROUND: Obesity is prevalent worldwide and is associated with insulin resistance. Advanced studies suggest that obesity-associated low-grade chronic inflammation contributes to the development of insulin resistance and other metabolic complications. Thrombospondin 1 (TSP1) is a multifunctional extracellular matrix protein that is up-regulated in inflamed adipose tissue. A recent study suggests a positive correlation of TSP1 with obesity, adipose inflammation, and insulin resistance. However, the direct effect of TSP1 on obesity and insulin resistance is not known. Therefore, we investigated the role of TSP1 in mediating obesity-associated inflammation and insulin resistance by using TSP1 knockout mice.

METHODOLOGY/PRINCIPAL FINDINGS: Male TSP1-/- mice …

Immunization With The Recombinant Antigen Ss-Ir Induces Protective Immunity To Infection With Strongyloides Stercoralis In Mice., David Abraham, Jessica A. Hess, Rojelio Mejia, Thomas J. Nolan, James B. Lok, Sara Lustigman, Thomas B. Nutman

Department of Microbiology and Immunology Faculty Papers

Human intestinal infections with the nematode Strongyloides stercoralis remain a significant problem worldwide and a vaccine would be a useful addition to the tools available to prevent and control this infection. The goal of this study was to test single antigens for their efficacy in a vaccine against S. stercoralis larvae in mice. Alum was used as the adjuvant in these studies and antigens selected for analysis were either recognized by protective human IgG (Ss-TMY-1, Ss-EAT-6, and Ss-LEC-5) or were known to be highly immunogenic in humans (Ss-NIE-1 and Ss-IR). Only mice immunized with the Ss-IR antigen demonstrated a significant …

Human Glial-Restricted Progenitor Transplantation Into Cervical Spinal Cord Of The Sod1 Mouse Model Of Als., Angelo C Lepore, John O'Donnell, Andrew S Kim, Timothy Williams, Alicia Tuteja, Mahendra S Rao, Linda L Kelley, James T Campanelli, Nicholas J Maragakis

Department of Neuroscience Faculty Papers

Cellular abnormalities are not limited to motor neurons in amyotrophic lateral sclerosis (ALS). There are numerous observations of astrocyte dysfunction in both humans with ALS and in SOD1(G93A) rodents, a widely studied ALS model. The present study therapeutically targeted astrocyte replacement in this model via transplantation of human Glial-Restricted Progenitors (hGRPs), lineage-restricted progenitors derived from human fetal neural tissue. Our previous findings demonstrated that transplantation of rodent-derived GRPs into cervical spinal cord ventral gray matter (in order to target therapy to diaphragmatic function) resulted in therapeutic efficacy in the SOD1(G93A) rat. Those findings demonstrated the feasibility and efficacy of transplantation-based …

Wolbachia Infections That Reduce Immature Insect Survival: Predicted Impacts On Population Replacement, Philip R. Crain, James W. Mains, Eunho Suh, Yunxin Huang, Philip H. Crowley, Stephen L. Dobson

Entomology Faculty Publications

BACKGROUND: The evolutionary success of Wolbachia bacteria, infections of which are widespread in invertebrates, is largely attributed to an ability to manipulate host reproduction without imposing substantial fitness costs. Here, we describe a stage-structured model with deterministic immature lifestages and a stochastic adult female lifestage. Simulations were conducted to better understand Wolbachia invasions into uninfected host populations. The model includes conventional Wolbachia parameters (the level of cytoplasmic incompatibility, maternal inheritance, the relative fecundity of infected females, and the initial Wolbachia infection frequency) and a new parameter termed relative larval viability (RLV), which is the survival of infected larvae relative to …

Demasculinization And Feminization Of Male Gonads By Atrazine: Consistent Effects Across Vertebrate Classes, Krista A. Mccoy

Integrative Biology Faculty and Staff Publications

Atrazine is the most commonly detected pesticide contaminant of ground water, surface water, and precipitation. Atrazine is also an endocrine disruptor that, among other effects, alters male reproductive tissues when animals are exposed during development. Here, we apply the nine so-called “Hill criteria” (Strength, Consistency, Specificity, Temporality, Biological Gradient, Plausibility, Coherence, Experiment, and Analogy) for establishing cause–effect relationships to examine the evidence for atrazine as an endocrine disruptor that demasculinizes and feminizes the gonads of male vertebrates. We present experimental evidence that the effects of atrazine on male development are consistent across all vertebrate classes examined and we present a …

Food Insecurity And Sexual Risk In An Hiv Endemic Community In Uganda, Cari L. Miller, David R. Bangsberg, David M. Tuller, Jude Senkungu, Annet Kawuma, Edward A. Frongillo Jr., Sheri D. Weiser

Faculty Publications

Food insecurity has been linked to high-risk sexual behavior in sub-Saharan Africa, but there are limited data on these links among people living with HIV/AIDS, and on the mechanisms for how food insecurity predisposes individuals to risky sexual practices. We undertook a series of in-depth open-ended interviews with 41 individuals living with HIV/AIDS to understand the impact of food insecurity on sexual-risk behaviors. Participants were recruited from the Immune Suppression Clinic at the Mbarara University of Science and Technology in Mbarara, Uganda. Interviews were recorded, transcribed verbatim, translated, and coded following the strategy of grounded theory. Four major themes emerged …

Reduced Cardioprotective Action Of Adiponectin In High-Fat Diet-Induced Type Ii Diabetic Mice And Its Underlying Mechanisms., Wei Yi, Yang Sun, Erhe Gao, Xufeng Wei, Wayne Bond Lau, Qijun Zheng, Yajing Wang, Yuexing Yuan, Xiaoliang Wang, Ling Tao, Rong Li, Walter Koch, Xin-Liang Ma

Department of Emergency Medicine Faculty Papers

Diabetes exacerbates ischemic heart disease morbidity and mortality via incompletely understood mechanisms. Although adiponectin (APN) reduces myocardial ischemia/reperfusion (MI/R) injury in nondiabetic animals, whether APN's cardioprotective actions are altered in diabetes, a pathologic condition with endogenously reduced APN, has never been investigated. High-fat diet (HD)-induced diabetic mice and normal diet (ND) controls were subjected to MI via coronary artery ligation, and given vehicle or APN globular domain (gAPN, 2 μg/g) 10 min before reperfusion. Compared to ND mice (where gAPN exerted pronounced cardioprotection), HD mice manifested greater MI/R injury, and a tripled gAPN dose was requisite to achieve cardioprotective extent …

Advanced Glycation End Products Accelerate Ischemia/Reperfusion Injury Through Receptor Of Advanced End Product/Nitrative Thioredoxin Inactivation In Cardiac Microvascular Endothelial Cells., Yi Liu, Yanzhuo Ma, Rutao Wang, Chenhai Xia, Rongqing Zhang, Kun Lian, Ronghua Luan, Lu Sun, Lu Yang, Wayne B Lau, Haichang Wang, Ling Tao

Department of Emergency Medicine Faculty Papers

The advanced glycation end products (AGEs) are associated with increased cardiac endothelial injury. However, no causative link has been established between increased AGEs and enhanced endothelial injury after ischemia/reperfusion. More importantly, the molecular mechanisms by which AGEs may increase endothelial injury remain unknown. Adult rat cardiac microvascular endothelial cells (CMECs) were isolated and incubated with AGE-modified bovine serum albumin (BSA) or BSA. After AGE-BSA or BSA preculture, CMECs were subjected to simulated ischemia (SI)/reperfusion (R). AGE-BSA increased SI/R injury as evidenced by enhanced lactate dehydrogenase release and caspase-3 activity. Moreover, AGE-BSA significantly increased SI/R-induced oxidative/nitrative stress in CMECs (as measured …

Functional Plasticity Of Central Trpv1 Receptors In Brainstem Dorsal Vagal Complex Circuits Of Streptozotocin-Treated Hyperglycemic Mice, Andrea Zsombok, Muthu D. Bhaskaran, Hong Gao, Andrei V. Derbenev, Bret N. Smith

Physiology Faculty Publications

Emerging data indicate that central neurons participate in diabetic processes by modulating autonomic output from neurons in the dorsal motor nucleus of the vagus (DMV). We tested the hypothesis that synaptic modulation by transient receptor potential vanilloid type 1 (TRPV1) receptors is reduced in the DMV in slices from a murine model of type 1 diabetes. The TRPV1 agonist capsaicin robustly enhanced glutamate release onto DMV neurons by acting at preterminal receptors in slices from intact mice, but failed to do so in slices from diabetic mice. TRPV1 receptor protein expression in the vagal complex was unaltered. Brief insulin preapplication …

Highly Variable Recessive Lthal Or Nearly Lethal Mutation Rates During Germ-Line Development Of Male Drosophila Melanogaster, Jian-Jun Gao, Xue-Rong Pan, Jing Hu, Li Ma, Jian-Min Wu, Ye-Lin Shao, Sara A Barton, Ronny C Woodruff, Ya-Ping Zhang, Yun-Xin Fu

Faculty, Staff and Student Publications

Each cell of higher organism adults is derived from a fertilized egg through a series of divisions, during which mutations can occur. Both the rate and timing of mutations can have profound impacts on both the individual and the population, because mutations that occur at early cell divisions will affect more tissues and are more likely to be transferred to the next generation. Using large-scale multigeneration screening experiments for recessive lethal or nearly lethal mutations of Drosophila melanogaster and recently developed statistical analysis, we show for male D. melanogaster that (i) mutation rates (for recessive lethal or nearly lethal) are …

Despotism And Risk Of Infanticide Influence Grizzly Bear Den-Site Selection, Nathan S. Libal, Jerrold L. Belant, Bruce D. Leopold, Guiming Wang, Patricia A. Owen

CFR Publications

Given documented social dominance and intraspecific predation in bear populations, the ideal despotic distribution model and sex hypothesis of sexual segregation predict adult female grizzly bears (Ursus arctos) will avoid areas occupied by adult males to reduce risk of infanticide. Under ideal despotic distribution, juveniles should similarly avoid adult males to reduce predation risk. Den-site selection and use is an important component of grizzly bear ecology and may be influenced by multiple factors, including risk from conspecifics. To test the role of predation risk and the sex hypothesis of sexual segregation, we compared adult female (n = 142), adult male …

In Vivo Microdialysis Reveals Age-Dependent Decrease Of Brain Interstitial Fluid Tau Levels In P301s Human Tau Transgenic Mice, Kaoru Yamada, John R. Cirrito, Floy R. Stewart, Hong Jiang, Mary Beth Finn, Brandon B. Holmes, Lester I. Binder, Eva-Maria Mandelkow, Marc I. Diamond, Virginia M.-Y. Lee, David M. Holtzman

Open Access Publications

Although tau is a cytoplasmic protein, it is also found in brain extracellular fluids, e.g., CSF. Recent findings suggest that aggregated tau can be transferred between cells and extracellular tau aggregates might mediate spread of tau pathology. Despite these data, details of whether tau is normally released into the brain interstitial fluid (ISF), its concentration in ISF in relation to CSF, and whether ISF tau is influenced by its aggregation are unknown. To address these issues, we developed a microdialysis technique to analyze monomeric ISF tau levels within the hippocampus of awake, freely moving mice. We detected tau in ISF …

Protoporphyrin Ix Fluorescence Contrast In Invasive Glioblastomas Is Linearly Correlated With Gd Enhanced Magnetic Resonance Image Contrast But Has Higher Diagnostic Accuracy, Kimberley S. Samkoe, Summer L. Gibbs-Strauss, Harold H. Yang, S. Khan Hekmatyar, P. Jack Hoopes, Julia A. O'Hara, Risto A. Kauppinen, Brian W. Pogue

Dartmouth Scholarship

The sensitivity and specificity of in vivo magnetic resonance (MR) imaging is compared with production of protoporphyrin IX (PpIX), determined ex vivo, in a diffusely infiltrating glioma. A human glioma transfected with green fluorescent protein, displaying diffuse, infiltrative growth, was implanted intracranially in athymic nude mice. Image contrast from corresponding regions of interest (ROIs) in in vivo MR and ex vivo fluorescence images was quantified. It was found that all tumor groups had statistically significant PpIX fluorescence contrast and that PpIX contrast demonstrated the best predictive power for tumor presence. Contrast from gadolinium enhanced T1-weighted (T1W+Gd) and absolute T2 …

Relationship Of Adipokines With Insulin Sensitivity In African Americans., Maria P Martinez Cantarin, Scott W Keith, Stephanie Deloach, Yonghong Huan, Bonita Falkner

Department of Medicine Faculty Papers

INTRODUCTION: Cytokines produced by adipose tissue, including adiponectin, have been associated with metabolic abnormalities. The purpose of this study was to examine the relationship of insulin sensitivity measured by euglycemic hyperinsulinemic insulin clamp with plasma adiponectin and other adipokines in young adult African Americans.

METHODS: Participants were healthy African Americans. Anthropometric measures, blood pressure, an oral glucose tolerance test and an euglycemic hyperinsulinemic insulin clamp were performed. Insulin sensitivity measurements were adjusted for percentage of fat mass. Plasma concentrations of adiponectin, plasminogen activator inhibitor-1 (PAI-1) and interleukin-6 (IL-6) were assayed on plasma from fasting blood samples. Pearson correlation coefficients and …

Critical Role Of Pi3k/Akt/Gsk3Β In Motoneuron Specification From Human Neural Stem Cells In Response To Fgf2 And Egf, Luis Ojeda, Junling Gao, Kristopher G. Hooten, Enyin Wang, Jason R. Thonhoff, Tiffany J. Dunn, Tianyan Gao, Ping Wu

Markey Cancer Center Faculty Publications

Fibroblast growth factor (FGF) and epidermal growth factor (EGF) are critical for the development of the nervous system. We previously discovered that FGF2 and EGF had opposite effects on motor neuron differentiation from human fetal neural stem cells (hNSCs), but the underlying mechanisms remain unclear. Here, we show that FGF2 and EGF differentially affect the temporal patterns of Akt and glycogen synthase kinase 3 beta (GSK3β) activation. High levels of phosphatidylinositol 3-kinase (PI3K)/Akt activation accompanied with GSK3β inactivation result in reduction of the motor neuron transcription factor HB9. Inhibition of PI3K/Akt by chemical inhibitors or RNA interference or overexpression of …

Srt1720 Improves Survival And Healthspan Of Obese Mice, Robin K. Minor, Joseph A. Baur, Ana P. Gomes, Theresa M. Ward, Anna Csiszar, Evi M. Mercken, Kotb Abdelmohsen, Yu-Kyong Shin, Carles Canto, Morten Scheibye-Knudsen, Melissa Krawczyk, Pablo M. Irusta, Alejandro Martín-Montalvo, Basil P. Hubbard, Yongqing Zhang, Elin Lehrmann, Alexa A. White, Nathan L. Price, William R. Swindell, Kevin J. Pearson, Kevin G. Becker, Vilhelm A. Bohr, Myriam Gorospe, Josephine M. Egan, Mark I. Talan, Johan Auwerx, Christoph H. Westphal, James L. Ellis, Zoltan Ungvari, George P. Vlasuk, Peter J. Elliott, David A. Sinclair, Rafael De Cabo

Graduate Center for Nutritional Sciences Faculty Publications

Sirt1 is an NAD(+)-dependent deacetylase that extends lifespan in lower organisms and improves metabolism and delays the onset of age-related diseases in mammals. Here we show that SRT1720, a synthetic compound that was identified for its ability to activate Sirt1 in vitro, extends both mean and maximum lifespan of adult mice fed a high-fat diet. This lifespan extension is accompanied by health benefits including reduced liver steatosis, increased insulin sensitivity, enhanced locomotor activity and normalization of gene expression profiles and markers of inflammation and apoptosis, all in the absence of any observable toxicity. Using a conditional SIRT1 knockout mouse and …