2018 Junior Investigator Grants
|Mitzi Gonzales, PhD||Establishing novel blood-based biomarkers for Alzheimer’s Disease in the Texas Alzheimer’s Research and Care Consortium|
|Ryan Huebinger, PhD||Immune profile investigations of Alzheimer’s Disease|
|Ines Moreno-Gonzalez, PhD||Stem cell-derived anti-inflammatory treatment for Alzheimer’s disease|
|Trung Nguyen, MD, PhD||Tau seeding and strain identification across the spectrum of Alzheimer’s Disease and Lewy Body pathology|
|Sandra Pritzkow, PhD||Development of a blood test for Alzheimer’s disease diagnosis|
|Sangram Raut, PhD||Brain targeted RNAi therapy for Alzheimer’s Disease|
Mitzi Gonzales, PhD
Department of Neurology
Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases
UT Health Science Center San Antonio
Title: Establishing novel blood-based biomarkers for Alzheimer’s Disease in the Texas Alzheimer’s Research and Care Consortium
At present, over 24 million people suffer from dementia and the global prevalence is predicted to nearly double over the next twenty years. Within the United States, Texas has an elevated dementia burden and will bear catastrophically high associated healthcare costs. Enhanced early detection, monitoring, and treatment will be crucial for managing this growing epidemic. The current gold-standard diagnostic assessments for dementia, namely magnetic resonance and positron emission tomography imaging, are costly and burdensome. Establishment of blood-based biomarkers for neurodegenerative disorders has significant potential to aid timely identification of affected individuals, predict disease progression, and monitor efficacy of newly emerging treatments. Alzheimer’s disease (AD) is a genetically and biologically multifactorial disease. Thus, our ability to develop new innovative treatments hinges upon a more complete understanding of underlying biological and cellular processes. Recent genetic studies have implicated heterogeneous pathophysiological processes in AD including abnormal protein folding, neuronal/gilal injury, and inflammation. Leveraging upon these findings, we propose to assess serum biomarkers of abnormal protein accumulation (tau), neuronal injury (NFL), altered protein folding (UCHL1), microglial inflammation (sCD-14, YKL-40), and astrogilal injury (GFAP) in over 3,000 ethnically diverse participants within TARCC. First, we will investigate whether concentrations of novel serum biomarkers for neurodegeneration (tau, NFL, UCHL1, GFAP, sCD-14, YKL-40) individually and collectively have diagnostic accuracy for detection of AD using the area under the receiver operating characteristic curve (AUROC) and machine learning based models (Aim 1). We will also explore the associations between serum biomarkers and cognitive outcomes with data already collected within TARCC (Aim 2). Finally, we will investigate whether the association of serum biomarkers with diagnostic group and cognition is modified by the well-established AD risk factor, APOE genotype (Aim 3). In summary, we propose to utilize the extensive clinical, cognitive, and laboratory data in the ethnically diverse TARCC cohort to establish a novel serum biomarker panel to improve timely diagnosis of AD. The development of this panel has tremendous potential to improve early disease diagnosis and monitor treatment progression. Additionally, findings hold promise to facilitate clinical trials aimed to slow the acceleration of cognitive decline and prevent dementia.
Ryan Huebinger, PhD
Department of Surgery
Peter O’Donnell Jr. Brain Institute
Title: Immune profile investigations of Alzheimer’s Disease
The hallmark features of AD include amyloid beta deposition, neurofibrillary tangles and neuronal degeneration, and are the most likely sources of inflammation associated with AD. The hallmark features of AD are readily distinguishable from those of patients with the neuro-inflammatory disease, Multiple Sclerosis (MS). We compared the immune profile of cerebrospinal fluid (CSF) cells between patients with AD and MS. In this preliminary cohort of AD patients, a more robust expansion of innate cell populations in the CSF than MS patients was observed (35.0% vs 2.6%, AD:MS). Furthermore, AD patients display a decreased frequency of CD4+ T cells in the CSF than MS patients (37.8% vs 61.5%, AD:MS).
To determine if systemic immune dysregulation was also present, we performed flow cytometry on blood samples of the pilot AD cohort and observed an expansion of innate cells and contraction of CD4+ T cells in the circulation. This shift in innate immune cell and CD4+ T cell frequency may impact antibody production since a healthy balance of innate immune cells and CD4+ T cells is critical for optimal B cell activation leading to antibody production.
Based on this preliminary data, we hypothesize that expansion of innate immune cells and contraction of CD4+ T cells as observed in the CSF and periphery contributes to AD development by impacting antibody production against Amyloid beta and Tau. To test this hypothesis, we will collect cerebrospinal fluid and peripheral blood from AD patients and age-matched healthy controls to analyze cellular and molecular aspects of the humoral immune compartment. This hypothesis will be addressed in two specific aims: Aim1: Determine the impact of innate cell expansion and CD4+ T cell contraction on antibody genetics. Aim 2: Determine the impact of innate cell expansion and CD4+ T cell contraction on anti-Abeta and anti-Tau antibody production. The key impact of this project is to map the impact of innate cell expansion and CD4+ T cell contraction on AD progression, particularly as it relates to humoral immunity. The results of this study may support the expanded use of immune-stimulating therapies at an earlier stage of disease when they are most likely to be effective.
Ines Moreno-Gonzalez, PhD
Department of Neurology
Mitchell Center for Alzheimer’s Disease & Brain Disorders
UT Health Science Center at Houston
Title: Stem cell-derived anti-inflammatory treatment for Alzheimer’s disease
Alzheimer’s disease (AD) is the most common neurodegenerative disease characterized by memory impairment and cognitive decline. The most prominent pathological hallmarks of the disease are the extracellular accumulation of amyloid β (Aβ) peptides in the form of plaques, the intracellular accumulation of hyper-phosphorylated tau (ptau) proteins as neurofibrillary tangles, and a neuroinflammatory process. Current treatments for AD only ameliorate the symptoms, but none of them delay or halt disease progression. As the disease continues to be a serious global health problem, novel therapies aimed at recovering brain tissue and functionality need to be developed. In recent years, stem cells have received growing attention as a potential therapy for brain disorders, such as AD. Particularly, an emerging and promising cellular approach to treat human disease is the use of stem cells. For the past 20 years, investigators have tried injecting stem cells into the brain in an attempt to get them to replace the cells lost in neurodegenerative diseases but there have been great technical challenges. Patients’ self-derive stem cells offer the possibility to avoid rejection and a more personalized treatment. Preliminary results from our lab indicate that peripheral treatment using neural precursors (NPs) obtained from stem cells ameliorates clinical symptoms and slow down the progression of different neurodegenerative diseases by reducing the inflammation in the brain. Our working hypothesis is that intravenous inoculation of NPs and their released factors can be used as a novel therapeutic treatment for AD. The main goal of this project is to develop a new approach for treating AD using a stem cell based non-invasive therapy. To achieve this goal, we plan to study the efficacy of peripheral administration of stem cells in animal models of AD. In addition, we plan to evaluate the efficacy of factors derived from stem cells in AD mouse models and analyze the profile of factors present in the conditioned media with a disease-modifying effect. The significance of the proposed experiments is that, if our hypothesis is correct, it may lead to a more personalized therapy for AD patients, since the cells can be obtained from the patient’s skin providing an effective, low risk, personalized treatment that will reduce the neuropathological and clinical manifestations of the disease.
Trung Nguyen, MD, PhD
Department of Neurology and Neurotherapeutics
Peter O’Donnell Jr. Brain Institute
Title: Tau seeding and strain identification across the spectrum of Alzheimer’s Disease and Lewy Body pathology
Alzheimer’s disease (AD) and dementia with Lewy bodies (DLB) are the leading causes of dementia. They have different clinical features and different types of brain pathology. AD pathology includes neurofibrillary tangles that consist of abnormal tau proteins. DLB and other Lewy body diseases are characterized by the presence of Lewy bodies (LB) consisting of abnormal α-synuclein accumulation. Patients often have mixed pathology as well. It is difficult to predict the presence of mixed pathology, but it can lead to more impairment and decline. We must understand how tau and α-synuclein interact to improve our abilities in diagnosing and treating neurodegenerative disorders. One overarching concept is that abnormal proteins like tau and α-synuclein spread throughout the brain like prions, where an abnormal type, or “strain,” of a protein that is more prone to accumulation can spread from cell to cell to convert normal native proteins to abnormal proteins. This then “seeds” further accumulation and spread of abnormal proteins. It is unclear if one type of protein seed (α-synuclein) can convert a different protein (tau). This may depend on the specific protein strain, for which tau has great diversity. We hypothesize that tau and α-synuclein interact to increased tau seeding in a tau strain dependent manner. We aim to test this hypothesis by studying autopsy specimens from subjects seen at UT Southwestern (UTSW) through the Texas Alzheimer’s Research and Care Consortium and the Alzheimer’s Disease Center. Of the 4171 subjects we have evaluated over the past 30 years, 578 autopsy cases have been obtained for the UTSW Neuropathology Laboratory Brain Bank. Many cases are from decades ago, so we will assure that each case is evaluated using contemporary protocols. We will select cases based on extent of AD and LB pathology: 1) AD-only pathology; 2) AD/low LB mixed pathology; 3) AD/high LB mixed pathology; 4) LB/low or no AD pathology. Cases will also be defined by clinical syndrome (AD or DLB) and whether it matched pathology (e.g. clinical AD with AD pathology), had mixed pathology, or had a mismatch with pathology (e.g. DLB with AD-only pathology). We will select up to 10 cases per group. We will collaborate with Dr. Diamond’s lab, who has published techniques for identifying different tau strains and measuring seeding activity. By applying prepared tissue samples to a biosensor cell line, tau seeding activity can be measured and tau strains can be identified by morphometry and biochemical studies. We will compare tau seeding activities and strain identities for each case to the tau and α-synuclein pathology seen on adjacent sections as well as between groups based on pathology and clinical diagnoses. We expect evidence showing that α-synuclein interacts and increases seeding of distinct tau strains that are more associated with LB pathology and a DLB syndrome. Our results will advance the understanding of disease mechanisms of AD and DLB and what happens in cases with mixed pathology, which is becoming even more important as we develop diagnostic agents and therapies designed to target specific proteins like tau or α-synuclein.
Sandra Pritzkow, PhD
Department of Neurology
Mitchell Center for Alzheimer’s Disease & Brain Disorders
UT Health Science Center at Houston
Title: Development of a blood test for Alzheimer’s disease diagnosis
One of the main problems in Alzheimer’s disease (AD) is the lack of an early, sensitive and objective laboratory diagnosis to identify individuals that will develop the disease before substantial brain damage. Extensive evidences indicate that a central event in AD is the misfolding, oligomerization and accumulation of amyloid-beta (Aβ) protein aggregates in the brain. Aβ oligomers are thought to be key for inducing brain degeneration in AD. Importantly, several pieces of evidence indicate that soluble Aβ oligomers circulate in biological fluids of patients with AD, likely much before the clinical symptoms of the disease. The main goal of this project is to develop a blood-based sensitive and objective laboratory diagnosis for AD. Our working hypothesis is that detection of misfolded Aβ oligomers circulating in blood may be the basis for an early biochemical diagnosis for AD. Our strategy for detection uses the functional property of misfolded oligomers of being able to seed the polymerization of monomeric Aβ. For this purpose, we invented the protein misfolding cyclic amplification (PMCA) technique, which is a platform technology to detect very small quantities of seeding-competent misfolded oligomeric proteins associated with various protein misfolding diseases. Currently, PMCA has been applied to detect misfolded prion protein implicated in prion diseases in various biological fluids, including blood and urine. Recently PMCA was adapted to detect soluble Aβ oligomers in cerebrospinal fluid of AD patients. The specific aims of this project are: (1) to optimize PMCA for detection of misfolded Aβ oligomers in human blood, (2) to study specificity and sensitivity using large number of blood samples and (3) to evaluate the utility of the technology for monitoring disease progression. The results generated in this project may lead to a much needed biochemical test for AD diagnosis in blood.
Sangram Raut, PhD
Department of Physiology and Anatomy
University of North Texas Health Science Center
Title: Brain targeted RNAi therapy for Alzheimer’s Disease
Development of Alzheimer’s disease (AD) drugs with novel mechanisms of action are urgently needed to effectively treat our steadily growing aging population especially when a drug developed by TauRx Pharmaceuticals failed in Phase 3 clinical trial conducted in 2016. Therapeutic nucleic acids have become increasingly effective as targeted pharmacologic agents due to their high degree of specificity and ability to inhibit target protein expression that is otherwise difficult to impact with drugs. Glycogen Synthase Kinase, GSK-3 enzyme isoforms (alpha and beta) play an important role in driving the Alzheimer’s disease progression by taking part in processing both amyloid precursor protein, APP, and tau. APP and Tau are two key pathways that drive the AD progression. Thus, inhibiting both GSK-3 isoforms could pave a road to newer AD therapeutics that can target multiple pathways. A major roadblock to this approach is delivering these therapeutic RNAs across the blood-brain barrier (BBB). Two different laboratories (Dr. Raut, Nanomedicine expert and Dr. Yang, Alzheimer’s expert) with complementary skill sets are working on this proposal. This proposal aims at delivering the specific siRNA against GSK-3 isoforms across BBB using biocompatible lipoprotein nanoparticles, which inherently have the ability to cross BBB without disturbing it, unlike several other approaches. First, we will design and develop a methodology for making siRNA-lipoprotein nanoparticles based on our previous experience. Then, we aim to screen several siRNAs in cells before treating AD animals to select one with highest therapeutic potential. Next, we will test the effectiveness of this siRNA and novel delivery system in two different AD animal models (Aβ and tau) testing their motor and cognitive functions to establish the reduced or reversed AD disease progression. The long-term objective of this project is to develop a therapeutic delivery to treat AD patients and it can be adapted to other neurodegenerative diseases thereby reducing the healthcare burden in the US aging population.
2014 Pilot Grants
|Ren-Qi Huang, PhD||Neuroprotection of nonfeminizing estrogens against cognitive deficits of Alzheimer’s Disease.|
|Steven Patrie, PhD||Computational tools for molecular proteotyping: A unique approach to Alzheimer’s disease biomarker discovery.|
|Anson Pierce, PhD||Does HSF1 over-expression enhance the proteostasis of TDP-43?|
|Paul C. Trippier, PhD||Identification of Aß-ABAD Interaction Inhibitors for Evaluation as Small Molecule.|
|Akihiko Urayama, PhD||Effect of Youthful Systemic Milieu on Alzheimer’s Disease Pathology.|
Ren-Qi Huang, PhD
Center for Neuroscience Discovery
University of North Texas Health Science Center
Title: Neuroprotection of nonfeminizing estrogens against cognitive deficits of Alzheimer’s Disease.
Abstract: Memory loss is a common problem in normal aging and is earliest and most recognized symptom in age-associated neurodegenerative diseases including Alzheimer’s (AD) and Parkinson’s disease. Accumulating evidence from clinical and basic studies supports the notion that the effects of estrogen on learning and memory are beneficial. Estrogens have been shown to be useful for the improvement of learning and memory, treatment and prevention or delay of the onset of AD. In addition to these neuroprotective effects of estrogens, estrogens produce female phenotype in both females and males. Moreover, estrogens also increase the risk of female hormone-sensitive cancers such as breast and endometrial cancer. These detrimental effects of estrogen are likely mediated via activation of classical estrogen receptors (ERs) and limit their potential therapeutic for widespread clinical application. Synthetic estrogen analogues, which lack genomic hormonal properties (so-called “nonfeminizing”) may be promising alternatives to natural estrogens to prevent AD- related cognitive decline not only in women but also in men. The ability of estrogen to positively influence cognitive function is likely due at least in part to the fact that it enhances hippocampal long-term potentiation (LTP), the cellular mechanism of long-term memory storage in the brain. Moreover, estrogen modulation of LTP appears to involve a nongenomic mechanism. We have discovered and synthesized over 70 novel nonfeminizing estrogenic compounds. In neuroprotection cell assays, many of these compounds are 10 to 100-time more potent as neuroprotectants than estrogen itself. While the neuroprotection of the nonfeminizing estrogens have been described in vitro and in vivo studies, the cognitive outcomes of such neuroprotection have not been studied. The overall goal of the project is to test the hypothesis that nonfeminizing estrogen analogues have potential utility in improving cognitive function in normal male and female and AD animals. The Specific Aims of the proposal are to: 1) determine whether modulation of hippocampal LTP by nonfeminizing estrogen is dependent on gender, 2) determine whether nonfeminizing estrogen modulates LTP in the brain of AD animal model, 3) determine whether nonfeminizing estrogen attenuates cognitive disorders in a transgenic AD animal model. The proposed experiments will be conducted utilizing in vitro electrophysiological techniques and in vivo behavioral assay. The results of the studies will provide critical evidence needed to demonstrate that nonfeminizing estrogen analogues may provide the cognitive benefits of estrogen without the detrimental side effects, which is the important step towards development of new therapeutics to treat AD. The pilot grant will provide needed resources for accumulating preliminary data essential for submission larger grants to NIH/NIA, state and private foundations.
Steven Patrie, PhD
John L. Roach Scholar in Biomedical Research
Department of Pathology
UT Southwestern Medical Center
Title: Computational tools for molecular proteotyping: A unique approach to Alzheimer’s disease biomarker discovery.
Abstract: Chemical reactions in eukaryotes are programmed both in time and space; however, external stimuli (environment and disease) continually highjack these processes. The goal of this research is to develop next generation molecular imaging tools that rapidly quantify hard to predict combinatorial chemistry on translated genes in the secretory pathway in the context of normal eukaryote physiology as well as pathobiology associated with Alzheimer’s disease spectrum disorders. Reading qualitative/ quantitative chemical alterations on intact proteins traversing the secretory pathway represents a significant challenge because concentrated-organelle processing leads to extreme chemical heterogeneity (e.g., N-linked glycosylation). To meet this challenge, we propose a novel model: glycoproteoform differential network analysis (GDNA) which will exploit the universality of physiochemical space (hydrophobicity, pI, and mass) covered by a multidimensional proteomics workflow developed in our lab that includes off-gel isoelectric focusing, liquid chromatography, and Fourier Transform Mass Spectrometry (FTMS). We will apply these techniques in longitudinal studies are expected to provide insights on whether abnormal glycosylation patterns observed in CSF of AD patients occur in response to brain insulin resistance or the occurrence of plaque development in and around brain cells.
Paul C. Trippier, PhD
Department of Pharmaceutical Sciences
Texas Tech University Health Sciences Center
Title: Identification of Aß-ABAD Interaction Inhibitors for Evaluation as Small Molecule
Therapeutics for the Treatment of Alzheimer’s Disease.
Abstract: Alzheimer’s disease (AD) is the most common form of dementia and memory loss. The disease gets worse over time and is usually associated with advancing age. There is no cure for AD and current drugs only have a minor effect in providing relief of symptoms. One of the major causes of the disease is thought to be the accumulation and aggregation of a protein fragment called beta-amyloid that forms plaques within the brain causing neuron cell death. An enzyme called amyloid binding alcohol dehydrogenase or ABAD has been identified as playing a key role in the development and progression of AD. The enzyme reacts with beta-amyloid causing a chemical reaction that enhances the protein fragments toxic effect and progression of the disease. If the ABAD enzyme is inhibited a protective effect is seen in neurons, which would reduce the severity of the disease. The goal of this project is to identify new compounds that act as inhibitors of the ABAD enzyme. Such compounds will be starting points for the design of potential drugs for the treatment of AD.
Anson Pierce, PhD
Department of Biochemistry and Molecular Biology
The University of Texas Medical Branch at Galveston
Cynthia Woods Mitchell Center for Neurodegenerative Diseases
Sealy Center for Vaccine Development
Title: Does HSF1 over-expression enhance the proteostasis of TDP-43?
Abstract: Impaired proteostasis allowing exposed hydrophobic surfaces on misfolded tau or Trans-activation response DNA binding protein (TDP-43) has been implicated in their aggregation and toxicity in age-associated dementias such as Alzheimer’s disease (AD) and frontotemporal dementia (FTLD). TDP-43 forms inclusions in 57% of AD, 51% of FTLD, and all sporadic amyotrophic lateral sclerosis (ALS), with frequent C-terminal cleavage. We have developed a quantitative covalent proteomic assay to measure surface hydrophobicity of soluble proteins in situ. Using this assay we demonstrate enhanced surface hydrophobicity of TDP-43 and its C-terminal fragments (CTFs). We have observed co-localization of several heat shock proteins (HSPs) to TDP-43 pathology in human AD brain samples. Heat shock factor 1 (HSF1) is a master transcription factor for HSPs. We observed that HSF1 activators protect cells from the pathology and toxicity associated with TDP-43 CTF over-expression. An HSF1 transgenic mouse we developed protects against ALS, and AD-like memory deficits in J20 mice. We will evaluate the biophysical relationship between HSP70 and TDP-43 in vitro and in vivo and determine its ability to mitigate the harmful physical properties of exposed surface hydrophobicity of TDP-43 and its cleavage products. We will test the neuroprotective effects of HSF1 on TDP-43 neuropathology by over-expressing HSF1 in a human TDP-43 overexpressing model. This study will enhance our understanding of the physical properties of soluble TDP-43 aggregates and given the availability of drugs targeting HSF1 activity, identify potential therapeutic avenues that protect against TDP-43 pathology as observed in AD and FTLD.
Akihiko Urayama, PhD
Department of Neurology
University of Texas Health Science Center Houston
Title: Effect of Youthful Systemic Milieu on Alzheimer’s Disease Pathology.
Abstract: This study addresses two rapidly emerging topics in Alzheimer’s disease (AD); (i) disease-modifying therapy by youthful systemic milieu, and (ii) identification of humoral factors in the youthful milieu that ameliorate AD pathology. Central events in AD include protein misfolding, self-aggregation and cerebral deposition of amyloid-beta (Aβ) as well as neurofibrillary tangles composed of hyperphosphorylated tau. Thus, prevention and removal of amyloidogenic components are considered the most promising strategy to treat AD. We have recently found that youthful systemic milieu provided by whole blood exchange treatment mitigated cerebral deposition of amyloid plaques which reflected in improved spatial memory function in AD model mice. Based on our findings, AD brain reflects the changes in periphery. Thus, elucidating the effects of systemically circulating factors including amyloidogenic components and cytokines on the course of AD may be of great importance to understand the peripheral nature in AD affecting brain pathology of AD. We hypothesize that youthful systemic milieu ameliorates tau pathology. We will address this hypothesis by determining (i) effects of young blood on cerebral deposition of neurofibrillary tangles, tau levels, and behavioral memory (Aim 1), and (ii) identification of humoral factors by comparing cytokines in the plasma and brain interstitial fluid (ISF) in P301S mice receiving youthful systemic milieu (Aim2). To extrapolate the findings in mice to humans, we will essentially utilize Harris Cohort resources. We will compare mouse data with the cytokine profiling in the cerebrospinal fluid and plasma from humans with deferent severity in AD and mild cognitive impairment. Therapeutic combination of humoral factors will have immediate translational advantages.