Medicine and Health Sciences Commons^™

Jun Upregulation Drives Aberrant Transposable Element Mobilization, Associated Innate Immune Response, And Impaired Neurogenesis In Alzheimer’S Disease, Chiara Scopa, Samantha Barnada, Maria Cicardi, Mo Singer, Davide Trotti, Marco Trizzino

Farber Institute for Neuroscience Faculty Papers

Adult neurogenic decline, inflammation, and neurodegeneration are phenotypic hallmarks of Alzheimer's disease (AD). Mobilization of transposable elements (TEs) in heterochromatic regions was recently reported in AD, but the underlying mechanisms are still underappreciated. Combining functional genomics with the differentiation of familial and sporadic AD patient derived-iPSCs into hippocampal progenitors, CA3 neurons, and cerebral organoids, we found that the upregulation of the AP-1 subunit, c-Jun, triggers decondensation of genomic regions containing TEs. This leads to the cytoplasmic accumulation of HERVK-derived RNA-DNA hybrids, the activation of the cGAS-STING cascade, and increased levels of cleaved caspase-3, suggesting the initiation of programmed cell death …

The Herbicide Glyphosate Inhibits Hippocampal Long-Term Potentiation And Learning Through Activation Of Pro-Inflammatory Signaling, Yukitoshi Izumi, Kazuko A O'Dell, Charles F Zorumski

2020-Current year OA Pubs

Glyphosate, a herbicide marketed as Roundup, is widely used but there are concerns this exposure could impair cognitive function. In the CA1 region of rat hippocampal slices, we investigated whether glyphosate alters synaptic transmission and long-term potentiation (LTP), a cellular model of learning and memory. Our hypothesis is that glyphosate alters neuronal function and impairs LTP induction via activation of pro-inflammatory processes. Roundup depressed excitatory synaptic potentials(EPSPs) in a dose-dependent manner with complete suppression at 2000 mg/L. At concentrations ≤ 20 mg/L Roundup did not affect basal transmission, but 4 mg/L Roundup administered for 30 min inhibited LTP induction. Acute …

Neuroanatomical And Neurochemical Effects Of Prolonged Social Isolation In Adult Mice, Vibol Heng, Michael Zigmond, Richard Jay Smeyne

Department of Neuroscience Faculty Papers

INTRODUCTION: As social animals, our health depends in part on interactions with other human beings. Yet millions suffer from chronic social isolation, including those in nursing/assisted living facilities, people experiencing chronic loneliness as well as those in enforced isolation within our criminal justice system. While many historical studies have examined the effects of early isolation on the brain, few have examined its effects when this condition begins in adulthood. Here, we developed a model of adult isolation using mice (C57BL/6J) born and raised in an enriched environment.

METHODS: From birth until 4 months of age C57BL/6J mice were raised in …

Platelet-Derived Exerkine Cxcl4/Platelet Factor 4 Rejuvenates Hippocampal Neurogenesis And Restores Cognitive Function In Aged Mice, Odette Leiter, David Brici, Stephen J Fletcher, Xuan Ling Hilary Yong, Jocelyn Widagdo, Nicholas Matigian, Adam B Schroer, Gregor Bieri, Daniel G Blackmore, Perry F Bartlett, Victor Anggono, Saul A Villeda, Tara L Walker

Journal Articles

The beneficial effects of physical activity on brain ageing are well recognised, with exerkines, factors that are secreted into the circulation in response to exercise, emerging as likely mediators of this response. However, the source and identity of these exerkines remain unclear. Here we provide evidence that an anti-geronic exerkine is secreted by platelets. We show that platelets are activated by exercise and are required for the exercise-induced increase in hippocampal precursor cell proliferation in aged mice. We also demonstrate that increasing the systemic levels of the platelet-derived exerkine CXCL4/platelet factor 4 (PF4) ameliorates age-related regenerative and cognitive impairments in …

Age-Related Decline In Hippocampal Tyrosine Phosphatase Ptpro Is A Mechanistic Factor In Chemotherapy-Related Cognitive Impairment., Zhimeng Yao, Hongmei Dong, Jianlin Zhu, Liang Du, Yichen Luo, Qing Liu, Shixin Liu, Yusheng Lin, Lu Wang, Shuhong Wang, Wei Wei, Keke Zhang, Qingjun Huang, Xiaojun Yu, Weijiang Zhao, Haiyun Xu, Xiaofu Qiu, Yunlong Pan, Xingxu Huang, Sai-Ching Jim Yeung, Dianzheng Zhang, Hao Zhang

PCOM Scholarly Papers

Chemotherapy-related cognitive impairment (CRCI) or "chemo brain" is a devastating neurotoxic sequela of cancer-related treatments, especially for the elderly individuals. Here we show that PTPRO, a tyrosine phosphatase, is highly enriched in the hippocampus, and its level is tightly associated with neurocognitive function but declined significantly during aging. To understand the protective role of PTPRO in CRCI, a mouse model was generated by treating Ptpro-/- female mice with doxorubicin (DOX) because Ptpro-/- female mice are more vulnerable to DOX, showing cognitive impairments and neurodegeneration. By analyzing PTPRO substrates that are neurocognition-associated tyrosine kinases, we found that SRC and EPHA4 are …

An Erp Measure Of Non-Conscious Memory Reveals Dissociable Implicit Processes In Human Recognition Using An Open-Source Automated Analytic Pipeline, Richard J. Addante, Javier Lopez-Calderon, Nathan Allen, Carter Luck, Alana Muller, Lindsey Sirianni, Cory S. Inman, Daniel L. Drake

Psychology Student Publications

Non-conscious processing of human memory has traditionally been difficult to objectively measure and thus understand. A prior study on a group of hippocampal amnesia (N = 3) patients and healthy controls (N = 6) used a novel procedure for capturing neural correlates of implicit memory using event-related potentials (ERPs): old and new items were equated for varying levels of memory awareness, with ERP differences observed from 400 to 800 ms in bilateral parietal regions that were hippocampal-dependent. The current investigation sought to address the limitations of that study by increasing the sample of healthy subjects (N = …

Microrna (Mirna) Complexity In Alzheimer’S Disease (Ad), Walter J. Lukiw

School of Medicine Faculty Publications

AD is a complex, progressive, age-related neurodegenerative disorder representing the most common cause of senile dementia and neurological dysfunction in our elderly domestic population. The widely observed heterogeneity of AD is a reflection of the complexity of the AD process itself and the altered molecular-genetic mechanisms operating in the diseased human brain and CNS. One of the key players in this complex regulation of gene expression in human pathological neurobiology are microRNAs (miRNAs) that, through their actions, shape the transcriptome of brain cells that normally associate with very high rates of genetic activity, gene transcription and messenger RNA (mRNA) generation. …

The Cortico-Limbo-Thalamo-Cortical Circuits: An Update To The Original Papez Circuit Of The Human Limbic System, Arash Kamali, Sofia Milosavljevic, Anusha Gandhi, Kinsey R Lano, Parnian Shobeiri, Farzaneh Ghazi Sherbaf, Haris I Sair, Roy F Riascos, Khader M Hasan

Journal Articles

The Papez circuit, first proposed by James Papez in 1937, is a circuit believed to control memory and emotions, composed of the cingulate cortex, entorhinal cortex, parahippocampal gyrus, hippocampus, hypothalamus, and thalamus. Pursuant to James Papez, Paul Yakovlev and Paul MacLean incorporated the prefrontal/orbitofrontal cortex, septum, amygdalae, and anterior temporal lobes into the limbic system. Over the past few years, diffusion-weighted tractography techniques revealed additional limbic fiber connectivity, which incorporates multiple circuits to the already known complex limbic network. In the current review, we aimed to comprehensively summarize the anatomy of the limbic system and elaborate on the anatomical connectivity …

Characterization Of Childhood Trauma, Hippocampal Mediation And Cannabis Use In A Large Dataset Of Psychosis And Non-Psychosis Individuals, Elisabetta C. Del Re, Walid Yassin, Victor Zeng, Sarah Keedy, Ney Alliey-Rodriguez, Elena Ivleva, Scott Hill, Nicole Rychagov, Jennifer E. Mcdowell, Jeffrey R. Bishop

School of Medicine Publications and Presentations

Background

Cannabis use (CA) and childhood trauma (CT) independently increase the risk of earlier psychosis onset; but their interaction in relation to psychosis risk and association with endocannabinoid-receptor rich brain regions, i.e. the hippocampus (HP), remains unclear. The objective was to determine whether lower age of psychosis onset (AgePsyOnset) is associated with CA and CT through mediation by the HP volumes, and genetic risk, as measured by schizophrenia polygene scores (SZ-PGRS).

Methods

Cross-sectional, case-control, multicenter sample from 5 metropolitan US regions. Participants (n = 1185) included 397 controls not affected by psychosis (HC); 209 participants with bipolar disorder type-1; …

A Learned Map For Places And Concepts In The Human Medial Temporal Lobe, Nora A. Herweg, Lukas Kunz, Daniel Schonhaut, Armin Brandt, Paul A. Wanda, Ashwini D. Sharan, Michael R. Sperling, Andreas Schulze-Bonhage, Michael J. Kahana

Department of Neurology Faculty Papers

Distinct lines of research in both humans and animals point to a specific role of the hippocampus in both spatial and episodic memory function. The discovery of concept cells in the hippocampus and surrounding medial temporal lobe (MTL) regions suggests that the MTL maps physical and semantic spaces with a similar neural architecture. Here, we studied the emergence of such maps using MTL microwire recordings from 20 patients (9 female, 11 male) navigating a virtual environment featuring salient landmarks with established semantic meaning. We present several key findings. The array of local field potentials in the MTL contains sufficient information …

Glutamate, And Its Relationship To Task-Induced Functional Connectivity In The Human Brain: A Focus On Schizophrenia, Kathleen Liu Young, John Kopchick, Jeffrey Stanley, Vaibhav Diwadkar

Medical Student Research Symposium

Glutamate is the brain’s major excitatory neurotransmitter mediating both neuroplasticity and network function (Zhou & Danbolt, 2014). Basal glutamate (Glu) measured using proton magnetic resonance spectroscopy (1H-MRS) provides insight into a region’s density of neuropil related to the glutamatergic system. Moreover, given the role of glutamate in mediating brain network function, Glu levels may play a role in the brain’s functional connectivity (FC), which is typically estimated from functional magnetic resonance imaging (fMRI) time series data. These questions converge when considering the clinical syndrome of schizophrenia (SCZ). Patients with SCZ show abnormalities in basal Glu in the hippocampus and prefrontal …

Allopregnanolone Effects On Inhibition In Hippocampal Parvalbumin Interneurons, Xinguo Lu, Peter Lambert, Ann Benz, Charles F. Zorumski, Steven J. Mennerick

2020-Current year OA Pubs

Allopregnanolone (AlloP) is a neurosteroid that potentiates ionotropic GABAergic (GABA

Young Astrocytic Mitochondria Attenuate The Elevated Level Of Ccl11 In The Aged Mice, Contributing To Cognitive Function Improvement, Ryosuke Tashiro, Dan Ozaki, Jesus Bautista-Garrido, Guanghua Sun, Lidiya Obertas, Alexis S Mobley, Gab Seok Kim, Jaroslaw Aronowski, Joo Eun Jung

Journal Articles

Aging drives cognitive decline, and mitochondrial dysfunction is a hallmark of age-induced neurodegeneration. Recently, we demonstrated that astrocytes secrete functional mitochondria (Mt), which help adjacent cells to resist damage and promote repair after neurological injuries. However, the relationship between age-dependent changes in astrocytic Mt function and cognitive decline remains poorly understood. Here, we established that aged astrocytes secret less functional Mt compared to young astrocytes. We found the aging factor C-C motif chemokine 11 (CCL11) is elevated in the hippocampus of aged mice, and that its level is reduced upon systemic administration of young Mt, in vivo. Aged mice receiving …

Cnih3 Deletion Dysregulates Dorsal Hippocampal Transcription Across The Estrous Cycle, Bernard Mulvey, Hannah E. Frye, Tania Lintz, Stuart Fass, Eric Tycksen, Elliot C. Nelson, Jose A. Morón, Joseph D. Dougherty

2020-Current year OA Pubs

In females, the hippocampus, a critical brain region for coordination of learning, memory, and behavior, displays altered physiology and behavioral output across the estrous or menstrual cycle. However, the molecular effectors and cell types underlying these observed cyclic changes have only been partially characterized to date. Recently, profiling of mice null for the AMPA receptor trafficking gene

Ssris Differentially Modulate The Effects Of Pro-Inflammatory Stimulation On Hippocampal Plasticity And Memory Via Sigma 1 Receptors And Neurosteroids, Yukitoshi Izumi, Angela M Reiersen, Eric J Lenze, Steven J Mennerick, Charles F Zorumski

2020-Current year OA Pubs

Certain selective serotonin reuptake inhibitors (SSRIs) have anti-inflammatory effects in preclinical models, and recent clinical studies suggest that fluvoxamine can prevent deterioration in patients with COVID-19, possibly through activating sigma 1 receptors (S1Rs). Here we examined potential mechanisms contributing to these effects of fluvoxamine and other SSRIs using a well-characterized model of pro-inflammatory stress in rat hippocampal slices. When hippocampal slices are exposed acutely to lipopolysaccharide (LPS), a strong pro-inflammatory stimulus, basal synaptic transmission in the CA1 region remains intact, but induction of long-term potentiation (LTP), a form of synaptic plasticity thought to contribute to learning and memory, is completely …

Hippocampal Versus Cortical Deletion Of Cholinergic Receptor Muscarinic 1 In Mice Differentially Affects Post-Translational Modifications And Supramolecular Assembly Of Respiratory Chain-Associated Proteins, Mitochondrial Ultrastructure, And Respiration: Implications In Alzheimer's Disease, Mohammad Golam Sabbir, Mamiko Swanson, Robert C. Speth, Benedict C. Albensi

HPD Articles

In a previous retrospective study using postmortem human brain tissues, we demonstrated that loss of Cholinergic Receptor Muscarinic 1 (CHRM1) in the temporal cortex of a subset of Alzheimer's patients was associated with poor survival, whereas similar loss in the hippocampus showed no such association. Mitochondrial dysfunction underlies Alzheimer's pathogenesis. Therefore, to investigate the mechanistic basis of our findings, we evaluated cortical mitochondrial phenotypes in Chrm1 knockout (Chrm1) mice. Cortical Chrm1 loss resulted in reduced respiration, reduced supramolecular assembly of respiratory protein complexes, and caused mitochondrial ultrastructural abnormalities. These mouse-based findings mechanistically linked cortical CHRM1 loss with poor survival of …

Regulation Of The Volume-Regulated Anion Channel Pore-Forming Subunit Lrrc8a In The Intrahippocampal Kainic Acid Model Of Mesial Temporal Lobe Epilepsy, Manolia R. Ghouli, Carrie R. Jonak, Rajan Sah, Todd A. Fiacco, Devin K. Binder

2020-Current year OA Pubs

Volume-regulated anion channels (VRACs) are a group of ubiquitously expressed outwardly-rectifying anion channels that sense increases in cell volume and act to return cells to baseline volume through an efflux of anions and organic osmolytes, including glutamate. Because cell swelling, increased extracellular glutamate levels, and reduction of the brain extracellular space (ECS) all occur during seizure generation, we set out to determine whether VRACs are dysregulated throughout mesial temporal lobe epilepsy (MTLE), the most common form of adult epilepsy. To accomplish this, we employed the IHKA experimental model of MTLE, and probed for the expression of LRRC8A, the essential pore-forming …