2
|
Goldberg AR, Dovas A, Torres D, Sharma SD, Mela A, Merricks EM, Olabarria M, Shokooh LA, Zhao HT, Kotidis C, Calvaresi P, Viswanathan A, Banu MA, Razavilar A, Sudhakar TD, Saxena A, Chokran C, Humala N, Mahajan A, Xu W, Metz JB, Chen C, Bushong EA, Boassa D, Ellisman MH, Hillman EMC, McKhann GM, Gill BJA, Rosenfeld SS, Schevon CA, Bruce JN, Sims PA, Peterka DS, Canoll P. Glioma-Induced Alterations in Excitatory Neurons are Reversed by mTOR Inhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.10.575092. [PMID: 38293120 PMCID: PMC10827113 DOI: 10.1101/2024.01.10.575092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Gliomas are highly aggressive brain tumors characterized by poor prognosis and composed of diffusely infiltrating tumor cells that intermingle with non-neoplastic cells in the tumor microenvironment, including neurons. Neurons are increasingly appreciated as important reactive components of the glioma microenvironment, due to their role in causing hallmark glioma symptoms, such as cognitive deficits and seizures, as well as their potential ability to drive glioma progression. Separately, mTOR signaling has been shown to have pleiotropic effects in the brain tumor microenvironment, including regulation of neuronal hyperexcitability. However, the local cellular-level effects of mTOR inhibition on glioma-induced neuronal alterations are not well understood. Here we employed neuron-specific profiling of ribosome-bound mRNA via 'RiboTag,' morphometric analysis of dendritic spines, and in vivo calcium imaging, along with pharmacological mTOR inhibition to investigate the impact of glioma burden and mTOR inhibition on these neuronal alterations. The RiboTag analysis of tumor-associated excitatory neurons showed a downregulation of transcripts encoding excitatory and inhibitory postsynaptic proteins and dendritic spine development, and an upregulation of transcripts encoding cytoskeletal proteins involved in dendritic spine turnover. Light and electron microscopy of tumor-associated excitatory neurons demonstrated marked decreases in dendritic spine density. In vivo two-photon calcium imaging in tumor-associated excitatory neurons revealed progressive alterations in neuronal activity, both at the population and single-neuron level, throughout tumor growth. This in vivo calcium imaging also revealed altered stimulus-evoked somatic calcium events, with changes in event rate, size, and temporal alignment to stimulus, which was most pronounced in neurons with high-tumor burden. A single acute dose of AZD8055, a combined mTORC1/2 inhibitor, reversed the glioma-induced alterations on the excitatory neurons, including the alterations in ribosome-bound transcripts, dendritic spine density, and stimulus evoked responses seen by calcium imaging. These results point to mTOR-driven pathological plasticity in neurons at the infiltrative margin of glioma - manifested by alterations in ribosome-bound mRNA, dendritic spine density, and stimulus-evoked neuronal activity. Collectively, our work identifies the pathological changes that tumor-associated excitatory neurons experience as both hyperlocal and reversible under the influence of mTOR inhibition, providing a foundation for developing therapies targeting neuronal signaling in glioma.
Collapse
Affiliation(s)
- Alexander R Goldberg
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Athanassios Dovas
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Daniela Torres
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Sohani Das Sharma
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY 10032
| | - Angeliki Mela
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Edward M Merricks
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Markel Olabarria
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | | | - Hanzhi T Zhao
- Laboratory for Functional Optical Imaging, Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Corina Kotidis
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Peter Calvaresi
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Ashwin Viswanathan
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Matei A Banu
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Aida Razavilar
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Tejaswi D Sudhakar
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Ankita Saxena
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Cole Chokran
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Nelson Humala
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Aayushi Mahajan
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Weihao Xu
- Laboratory for Functional Optical Imaging, Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Jordan B Metz
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY 10032
| | - Cady Chen
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Eric A Bushong
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniela Boassa
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, University of California, San Diego, La Jolla, CA 92093, USA
| | - Elizabeth M C Hillman
- Laboratory for Functional Optical Imaging, Zuckerman Mind Brain Behavior Institute, Departments of Biomedical Engineering and Radiology, Columbia University, New York, NY 10027, USA
| | - Guy M McKhann
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Brian J A Gill
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | | | - Catherine A Schevon
- Department of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jeffrey N Bruce
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Peter A Sims
- Department of Systems Biology, Columbia University Irving Medical Center, New York, NY 10032
- Sulzberger Columbia Genome Center, Columbia University Irving Medical Center, New York, NY, 10032
- Department of Biochemistry & Molecular Biophysics, Columbia University Irving Medical Center, New York, NY, 10032
| | - Darcy S Peterka
- Irving Institute for Cancer Dynamics, Columbia University, New York, NY 10027, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Peter Canoll
- Department of Pathology and Cell Biology, Irving Cancer Research Center, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Neurological Surgery, Columbia University Irving Medical Center, New York, NY 10032, USA
| |
Collapse
|
4
|
Jean G, Carton J, Haq K, Musto AE. The role of dendritic spines in epileptogenesis. Front Cell Neurosci 2023; 17:1173694. [PMID: 37601280 PMCID: PMC10433379 DOI: 10.3389/fncel.2023.1173694] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 07/06/2023] [Indexed: 08/22/2023] Open
Abstract
Epilepsy is a chronic central nervous system (CNS) disease associated with high morbidity. To date, there is no known disease-modifying therapy for epilepsy. A leading hypothesis for a mechanism of epileptogenesis is the generation of aberrant neuronal networks. Although the underlying biological mechanism is not clear, scientific evidence indicates that it is associated with a hyperexcitable synchronous neuronal network and active dendritic spine plasticity. Changes in dendritic spine morphology are related to altered expression of synaptic cytoskeletal proteins, inflammatory molecules, neurotrophic factors, and extracellular matrix signaling. However, it remains to be determined if these aberrant dendritic spine formations lead to neuronal hyperexcitability and abnormal synaptic connections or whether they constitute an underlying mechanism of seizure susceptibility. Focusing on dendritic spine machinery as a potential target for medications could limit or reverse the development of epilepsy.
Collapse
Affiliation(s)
- Gary Jean
- Medical Program, School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Joseph Carton
- Medical Program, School of Medicine, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Kaleem Haq
- Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, VA, United States
| | - Alberto E. Musto
- Department of Pathology and Anatomy, Eastern Virginia Medical School, Norfolk, VA, United States
- Department of Neurology, Eastern Virginia Medical School, Norfolk, VA, United States
| |
Collapse
|
5
|
Eyo UB, Haruwaka K, Mo M, Campos-Salazar AB, Wang L, Speros XS, Sabu S, Xu P, Wu LJ. Microglia provide structural resolution to injured dendrites after severe seizures. Cell Rep 2021; 35:109080. [PMID: 33951432 PMCID: PMC8164475 DOI: 10.1016/j.celrep.2021.109080] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 02/01/2021] [Accepted: 04/13/2021] [Indexed: 12/19/2022] Open
Abstract
Although an imbalance between neuronal excitation and inhibition underlies seizures, clinical approaches that target these mechanisms are insufficient in containing seizures in patients with epilepsy, raising the need for alternative approaches. Brain-resident microglia contribute to the development and stability of neuronal structure and functional networks that are perturbed during seizures. However, the extent of microglial contributions in response to seizures in vivo remain to be elucidated. Using two-photon in vivo imaging to visualize microglial dynamics, we show that severe seizures induce formation of microglial process pouches that target but rarely engulf beaded neuronal dendrites. Microglial process pouches are stable for hours, although they often shrink in size. We further find that microglial process pouches are associated with a better structural resolution of beaded dendrites. These findings provide evidence for the structural resolution of injured dendrites by microglia as a form of neuroprotection.
Collapse
Affiliation(s)
- Ukpong B Eyo
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA; Brain Immunology and Glia Center, Department of Cell Biology and Neuroscience, University of Virginia, Charlottesville, VA 22908, USA.
| | | | - Mingshu Mo
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA; Department of Neurology, First Affiliated Hospital of Guangzhou Medical University, Guangdong 510120, China
| | - Antony Brayan Campos-Salazar
- Brain Immunology and Glia Center, Department of Cell Biology and Neuroscience, University of Virginia, Charlottesville, VA 22908, USA
| | - Lingxiao Wang
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Xenophon S Speros
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Sruchika Sabu
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA
| | - Pingyi Xu
- Department of Neurology, First Affiliated Hospital of Guangzhou Medical University, Guangdong 510120, China
| | - Long-Jun Wu
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA; Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854, USA; Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA; Department of Immunology, Mayo Clinic, Rochester, MN 55905, USA.
| |
Collapse
|
6
|
Schartz ND, Sommer AL, Colin SA, Mendez LB, Brewster AL. Early treatment with C1 esterase inhibitor improves weight but not memory deficits in a rat model of status epilepticus. Physiol Behav 2019; 212:112705. [PMID: 31628931 PMCID: PMC6879103 DOI: 10.1016/j.physbeh.2019.112705] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 09/20/2019] [Accepted: 10/07/2019] [Indexed: 12/22/2022]
Abstract
BACKGROUND Status epilepticus (SE) is a prolonged and continuous seizure that lasts for at least 5 min. An episode of SE in a healthy system can lead to the development of spontaneous seizures and cognitive deficits which may be accompanied by hippocampal injury and microgliosis. Although the direct mechanisms underlying the SE-induced pathophysiology remain unknown, a candidate mechanism is hyperactivation of the classical complement pathway (C1q-C3 signaling). We recently reported that SE triggered an increase in C1q-C3 signaling in the hippocampus that closely paralleled cognitive decline. Thus, we hypothesized that blocking activation of the classical complement pathway immediately after SE may prevent the development of SE-induced hippocampal-dependent learning and memory deficits. METHODS Because C1 esterase inhibitor (C1-INH) negatively regulates activation of the classical complement pathway, we used this drug to test our hypothesis. Two groups of male rats were subjected to 1 hr of SE with pilocarpine (280-300 mg/kg, i.p.), and treated with either C1-INH (SE+C1-INH, 20 U/kg, s.c.) or vehicle (SE+veh) at 4, 24, and 48 h after SE. Control rats were treated with saline. Body weight was recorded for up to 23 days after SE. At two weeks post SE, recognition and spatial memory were determined using Novel Object Recognition (NOR) and Barnes maze (BM), respectively, as well as locomotion and anxiety-like behaviors using Open Field (OF). Histological and biochemical methods were used to measure hippocampal injury including cell death, microgliosis, and inflammation. RESULTS One day after SE, both SE groups had a significant loss of body weight compared to controls (p<0.05). By day 14, the weight of SE+C1-INH rats was significantly higher than SE+veh rats (p<0.05), and was not different from controls (p>0.05). At 14 days post-SE, SE+C1-INH rats displayed higher mobility (distance travelled and average speed, p<0.05) and had reduced anxiety-like behaviors (outer duration, p<0.05) than control or SE+veh rats. In NOR, control rats spent significantly more time exploring the novel object vs. the familiar (p<0.05), while rats in both SE groups spent similar amount of time exploring both objects. During days 1-4 of BM training, the escape latency of the control group significantly decreased over time (p<0.05), whereas that of the SE groups did not improve (p>0.05). Compared to vehicle-treated SE rats, SE+C1-INH rats had increased levels of C3 and microglia in the hippocampus, but lower levels of caspase-3 and synaptic markers. CONCLUSIONS These findings suggest that acute treatment with C1-INH after SE may have some protective, albeit limited, effects on the physiological recovery of rats' weight and some anxiolytic effects, but does not attenuate SE-induced deficits in hippocampal-dependent learning and memory. Reduced levels of caspase-3 suggest that treatment with C1-INH may protect against cell death, perhaps by regulating inflammatory pathways and promoting phagocytic/clearance pathways.
Collapse
Affiliation(s)
- Nicole D Schartz
- Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USA.
| | - Alexandra L Sommer
- Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USA.
| | - Samantha A Colin
- Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USA.
| | - Loyda B Mendez
- School of Science & Technology, Ana G. Méndez University, Carolina, PR 00984, USA.
| | - Amy L Brewster
- Department of Psychological Sciences, Purdue University, West Lafayette, IN 47907, USA; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN 47907, USA; Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47907, USA.
| |
Collapse
|
7
|
Hodges SL, Lugo JN. Wnt/β-catenin signaling as a potential target for novel epilepsy therapies. Epilepsy Res 2018; 146:9-16. [PMID: 30053675 DOI: 10.1016/j.eplepsyres.2018.07.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 06/28/2018] [Accepted: 07/11/2018] [Indexed: 01/01/2023]
Abstract
Epilepsy is one of the most common neurological disorders, and yet many afflicted individuals are resistant to all available therapeutic treatments. Existing pharmaceutical treatments function primarily to reduce hyperexcitability and prevent seizures, but fail to influence the underlying pathophysiology of the disorder. Recently, research efforts have focused on identifying alternative mechanistic targets for anti-epileptogenic therapies that can prevent the development of chronic epilepsy. The Wnt/β-catenin pathway, one possible target, has been demonstrated to be disrupted in both acute and chronic phases of epilepsy. Wnt/β-catenin signaling can regulate many seizure-induced changes in the brain, including neurogenesis and neuronal death, as well as can influence seizure susceptibility and potentially the development of chronic epilepsy. Several genome-wide studies and in vivo knockout animal models have provided evidence for an association between disrupted Wnt/β-catenin signaling and epilepsy. Furthermore, approved pharmaceutical drugs and other small molecule compounds that target components of the β-catenin destruction complex or antagonize endogenous inhibitors of the pathway have shown to be protective following seizures. However, additional studies are needed to determine the optimal time period in which modulation of the pathway may be most beneficial. Overall, disrupted molecular networks such as Wnt/β-catenin signaling, could be a promising anti-epileptogenic target for future epilepsy therapies.
Collapse
Affiliation(s)
- Samantha L Hodges
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA
| | - Joaquin N Lugo
- Institute of Biomedical Studies, Baylor University, Waco, TX, 76798, USA; Department of Psychology and Neuroscience, Baylor University, Waco, TX, 76798, USA; Department of Biology, Baylor University, Waco, TX, 76798, USA.
| |
Collapse
|