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Valentim WL, Tylee DS, Polimanti R. A perspective on translating genomic discoveries into targets for brain-machine interface and deep brain stimulation devices. WIREs Mech Dis 2024; 16:e1635. [PMID: 38059513 PMCID: PMC11163995 DOI: 10.1002/wsbm.1635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 10/22/2023] [Accepted: 11/17/2023] [Indexed: 12/08/2023]
Abstract
Mental illnesses have a huge impact on individuals, families, and society, so there is a growing need for more efficient treatments. In this context, brain-computer interface (BCI) technology has the potential to revolutionize the options for neuropsychiatric therapies. However, the development of BCI-based therapies faces enormous challenges, such as power dissipation constraints, lack of credible feedback mechanisms, uncertainty of which brain areas and frequencies to target, and even which patients to treat. Some of these setbacks are due to the large gap in our understanding of brain function. In recent years, large-scale genomic analyses uncovered an unprecedented amount of information regarding the biology of the altered brain function observed across the psychopathology spectrum. We believe findings from genetic studies can be useful to refine BCI technology to develop novel treatment options for mental illnesses. Here, we assess the latest advancements in both fields, the possibilities that can be generated from their intersection, and the challenges that these research areas will need to address to ensure that translational efforts can lead to effective and reliable interventions. Specifically, starting from highlighting the overlap between mechanisms uncovered by large-scale genetic studies and the current targets of deep brain stimulation treatments, we describe the steps that could help to translate genomic discoveries into BCI targets. Because these two research areas have not been previously presented together, the present article can provide a novel perspective for scientists with different research backgrounds. This article is categorized under: Neurological Diseases > Genetics/Genomics/Epigenetics Neurological Diseases > Biomedical Engineering.
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Affiliation(s)
- Wander L. Valentim
- Faculty of Medicine, Federal University of Minas Gerais, Belo Horizonte, Brazil
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT
| | - Daniel S. Tylee
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT
- VA CT Healthcare Center, West Haven, CT, USA
| | - Renato Polimanti
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT
- VA CT Healthcare Center, West Haven, CT, USA
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2
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Del Pilar C, Garrido-Matilla L, Del Pozo-Filíu L, Lebrón-Galán R, Arias RF, Clemente D, Alonso JR, Weruaga E, Díaz D. Intracerebellar injection of monocytic immature myeloid cells prevents the adverse effects caused by stereotactic surgery in a model of cerebellar neurodegeneration. J Neuroinflammation 2024; 21:49. [PMID: 38355633 PMCID: PMC10867997 DOI: 10.1186/s12974-023-03000-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 12/18/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Myeloid-derived suppressor cells (MDSCs) constitute a recently discovered bone-marrow-derived cell type useful for dealing with neuroinflammatory disorders. However, these cells are only formed during inflammatory conditions from immature myeloid cells (IMCs) that acquire immunosuppressive activity, thus being commonly gathered from diseased animals. Then, to obtain a more clinically feasible source, we characterized IMCs directly derived from healthy bone marrow and proved their potential immunosuppressive activity under pathological conditions in vitro. We then explored their neuroprotective potential in a model of human cerebellar ataxia, the Purkinje Cell Degeneration (PCD) mouse, as it displays a well-defined neurodegenerative and neuroinflammatory process that can be also aggravated by invasive surgeries. METHODS IMCs were obtained from healthy bone marrow and co-cultured with activated T cells. The proliferation and apoptotic rate of the later were analyzed with Tag-it Violet. For in vivo studies, IMCs were transplanted by stereotactic surgery into the cerebellum of PCD mice. We also used sham-operated animals as controls of the surgical effects, as well as their untreated counterparts. Motor behavior of mice was assessed by rotarod test. The Purkinje cell density was measured by immunohistochemistry and cell death assessed with the TUNEL technique. We also analyzed the microglial phenotype by immunofluorescence and the expression pattern of inflammation-related genes by qPCR. Parametric tests were applied depending on the specific experiment: one or two way ANOVA and Student's T test. RESULTS IMCs were proven to effectively acquire immunosuppressive activity under pathological conditions in vitro, thus acting as MDSCs. Concerning in vivo studios, sham-operated PCD mice suffered detrimental effects in motor coordination, Purkinje cell survival and microglial activation. After intracranial administration of IMCs into the cerebellum of PCD mice, no special benefits were detected in the transplanted animals when compared to untreated mice. Nonetheless, this transplant almost completely prevented the impairments caused by the surgery in PCD mice, probably by the modulation of the inflammatory patterns. CONCLUSIONS Our work comprise two main translational findings: (1) IMCs can be directly used as they behave as MDSCs under pathological conditions, thus avoiding their gathering from diseased subjects; (2) IMCs are promising adjuvants when performing neurosurgery.
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Affiliation(s)
- Carlos Del Pilar
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain
- Institute of Biomedical Research of Salamanca, IBSAL, Salamanca, Spain
| | - Lucía Garrido-Matilla
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain
- Departamento de Psicobiología, Facultad de Psicología, Universidad Nacional de Educación a Distancia (UNED), Madrid, Spain
| | - Lucía Del Pozo-Filíu
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain
- Translational Stroke Laboratory (TREAT), Clinical Neurosciences Research Laboratory (LINC), Health Research Institute of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | - Rafael Lebrón-Galán
- Neuroimmuno-Repair Group, Hospital Nacional de Parapléjicos-SESCAM, Finca La Peraleda s/n, 45004, Toledo, Spain
- Hospital Universitario de Toledo, Avd. Río Guadiana, s/n, 45007, Toledo, Spain
| | - Raúl F Arias
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain
- Institute of Biomedical Research of Salamanca, IBSAL, Salamanca, Spain
| | - Diego Clemente
- Neuroimmuno-Repair Group, Hospital Nacional de Parapléjicos-SESCAM, Finca La Peraleda s/n, 45004, Toledo, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Carlos III Health Institute, Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain
| | - José Ramón Alonso
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain
- Institute of Biomedical Research of Salamanca, IBSAL, Salamanca, Spain
| | - Eduardo Weruaga
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain.
- Institute of Biomedical Research of Salamanca, IBSAL, Salamanca, Spain.
| | - David Díaz
- Institute for Neuroscience of Castile and Leon, INCyL, Universidad de Salamanca, C/Pintor Fernando Gallego 1, 37007, Salamanca, Spain.
- Institute of Biomedical Research of Salamanca, IBSAL, Salamanca, Spain.
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Erden YJ, Brey P. Neurotechnology and ethics guidelines for human enhancement: The case of the hippocampal cognitive prosthesis. Artif Organs 2023; 47:1235-1241. [PMID: 37533179 DOI: 10.1111/aor.14615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/04/2023]
Abstract
Neurotechnologies offer both therapeutic and enhancement potential. In this article, we demonstrate how ethics guidelines can help with critical reflection on their potential for enhancement. We do this through the case of the hippocampal cognitive prosthesis. This prothesis developed in the US, has primarily therapeutic ends, with scope for enhancement. This technology raises several ethical issues, including as related to identity and memory, autonomy and authenticity. In the first section, we outline what we mean by enhancement, and introduce neurotechnologies generally and the hippocampal cognitive prosthesis specifically, with an introduction to generally relevant ethical issues. In the second section, we outline ethical issues pertinent to the hippocampal cognitive prosthesis and explore how ethics guidelines can help to promote essential critical reflection on a technology like this. Through all this, our emphasis is to balance between technological optimism and caution, especially where technologies have enhancement potential.
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Affiliation(s)
- Yasemin J Erden
- Philosophy Section, Faculty of Behavioural, Management and Social Sciences, University of Twente, Enschede, The Netherlands
| | - Philip Brey
- Philosophy Section, Faculty of Behavioural, Management and Social Sciences, University of Twente, Enschede, The Netherlands
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Mousavinejad M, Skidmore S, Barone FG, Tyers P, Pisupati V, Poptani H, Plagge A, Barker RA, Murray P, Taylor A, Hill CJ. Assessing Human Embryonic Stem Cell-Derived Dopaminergic Neuron Progenitor Transplants Using Non-invasive Imaging Techniques. Mol Imaging Biol 2021; 22:1244-1254. [PMID: 32378000 PMCID: PMC7497430 DOI: 10.1007/s11307-020-01499-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Human pluripotent stem cell (hPSC)-derived dopaminergic neuron progenitor cells (DAPCs) are a potential therapy for Parkinson's disease (PD). However, their intracranial administration raises safety concerns including uncontrolled proliferation, migration and inflammation. Here, we apply a bimodal imaging approach to investigate the fate of DAPC transplants in the rat striatum. PROCEDURES DAPCs co-expressing luciferase and ZsGreen or labelled with micron-sized particles of iron oxide (MPIOs) were transplanted in the striatum of RNU rats (n = 6 per group). DAPCs were tracked in vivo using bioluminescence and magnetic resonance (MR) imaging modalities. RESULTS Transgene silencing in differentiating DAPCs accompanied with signal attenuation due to animal growth rendered the bioluminescence undetectable by week 2 post intrastriatal transplantation. However, MR imaging of MPIO-labelled DAPCs showed that transplanted cells remained at the site of injection for over 120 days. Post-mortem histological analysis of DAPC transplants demonstrated that labelling with either luciferase/ZsGreen or MPIOs did not affect the ability of cells to differentiate into mature dopaminergic neurons. Importantly, labelled cells did not elicit increased glial reactivity compared to non-labelled cells. CONCLUSIONS In summary, our findings support the transplantation of hPSC-derived DAPCs as a safe treatment for PD.
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Affiliation(s)
- M Mousavinejad
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK
| | - S Skidmore
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK.,WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - F G Barone
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK
| | - P Tyers
- John van Geest Centre for Brain Repair & Department of Neurology, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - V Pisupati
- WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - H Poptani
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK
| | - A Plagge
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK
| | - R A Barker
- WT-MRC Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK.,John van Geest Centre for Brain Repair & Department of Neurology, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - P Murray
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK
| | - A Taylor
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK.
| | - C J Hill
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool, L69 3BX, UK. .,Centre for Women's Health Research, Department of Women's and Children's Health, Institute of Translational Medicine, University of Liverpool, Liverpool, L8 7SS, UK.
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Korai SA, Ranieri F, Di Lazzaro V, Papa M, Cirillo G. Neurobiological After-Effects of Low Intensity Transcranial Electric Stimulation of the Human Nervous System: From Basic Mechanisms to Metaplasticity. Front Neurol 2021; 12:587771. [PMID: 33658972 PMCID: PMC7917202 DOI: 10.3389/fneur.2021.587771] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 01/04/2021] [Indexed: 12/19/2022] Open
Abstract
Non-invasive low-intensity transcranial electrical stimulation (tES) of the brain is an evolving field that has brought remarkable attention in the past few decades for its ability to directly modulate specific brain functions. Neurobiological after-effects of tES seems to be related to changes in neuronal and synaptic excitability and plasticity, however mechanisms are still far from being elucidated. We aim to review recent results from in vitro and in vivo studies that highlight molecular and cellular mechanisms of transcranial direct (tDCS) and alternating (tACS) current stimulation. Changes in membrane potential and neural synchronization explain the ongoing and short-lasting effects of tES, while changes induced in existing proteins and new protein synthesis is required for long-lasting plastic changes (LTP/LTD). Glial cells, for decades supporting elements, are now considered constitutive part of the synapse and might contribute to the mechanisms of synaptic plasticity. This review brings into focus the neurobiological mechanisms and after-effects of tDCS and tACS from in vitro and in vivo studies, in both animals and humans, highlighting possible pathways for the development of targeted therapeutic applications.
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Affiliation(s)
- Sohaib Ali Korai
- Division of Human Anatomy - Laboratory of Neuronal Networks, University of Campania "Luigi Vanvitelli", Naples, Italy
| | - Federico Ranieri
- Neurology Unit, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Vincenzo Di Lazzaro
- Neurology, Neurophysiology and Neurobiology Unit, University Campus Bio-Medico, Rome, Italy
| | - Michele Papa
- Division of Human Anatomy - Laboratory of Neuronal Networks, University of Campania "Luigi Vanvitelli", Naples, Italy.,ISBE Italy, SYSBIO Centre of Systems Biology, Milan, Italy
| | - Giovanni Cirillo
- Division of Human Anatomy - Laboratory of Neuronal Networks, University of Campania "Luigi Vanvitelli", Naples, Italy.,Neurology Unit, Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
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6
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How is flexible electronics advancing neuroscience research? Biomaterials 2020; 268:120559. [PMID: 33310538 DOI: 10.1016/j.biomaterials.2020.120559] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 11/16/2020] [Accepted: 11/18/2020] [Indexed: 02/07/2023]
Abstract
Innovative neurotechnology must be leveraged to experimentally answer the multitude of pressing questions in modern neuroscience. Driven by the desire to address the existing neuroscience problems with newly engineered tools, we discuss in this review the benefits of flexible electronics for neuroscience studies. We first introduce the concept and define the properties of flexible and stretchable electronics. We then categorize the four dimensions where flexible electronics meets the demands of modern neuroscience: chronic stability, interfacing multiple structures, multi-modal compatibility, and neuron-type-specific recording. Specifically, with the bending stiffness now approaching that of neural tissue, implanted flexible electronic devices produce little shear motion, minimizing chronic immune responses and enabling recording and stimulation for months, and even years. The unique mechanical properties of flexible electronics also allow for intimate conformation to the brain, the spinal cord, peripheral nerves, and the retina. Moreover, flexible electronics enables optogenetic stimulation, microfluidic drug delivery, and neural activity imaging during electrical stimulation and recording. Finally, flexible electronics can enable neuron-type identification through analysis of high-fidelity recorded action potentials facilitated by its seamless integration with the neural circuitry. We argue that flexible electronics will play an increasingly important role in neuroscience studies and neurological therapies via the fabrication of neuromorphic devices on flexible substrates and the development of enhanced methods of neuronal interpenetration.
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Woods GA, Rommelfanger NJ, Hong G. Bioinspired Materials for In Vivo Bioelectronic Neural Interfaces. MATTER 2020; 3:1087-1113. [PMID: 33103115 PMCID: PMC7583599 DOI: 10.1016/j.matt.2020.08.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The success of in vivo neural interfaces relies on their long-term stability and large scale in interrogating and manipulating neural activity after implantation. Conventional neural probes, owing to their limited spatiotemporal resolution and scale, face challenges for studying the massive, interconnected neural network in its native state. In this review, we argue that taking inspiration from biology will unlock the next generation of in vivo bioelectronic neural interfaces. Reducing the feature sizes of bioelectronic neural interfaces to mimic those of neurons enables high spatial resolution and multiplexity. Additionally, chronic stability at the device-tissue interface is realized by matching the mechanical properties of bioelectronic neural interfaces to those of the endogenous tissue. Further, modeling the design of neural interfaces after the endogenous topology of the neural circuitry enables new insights into the connectivity and dynamics of the brain. Lastly, functionalization of neural probe surfaces with coatings inspired by biology leads to enhanced tissue acceptance over extended timescales. Bioinspired neural interfaces will facilitate future developments in neuroscience studies and neurological treatments by leveraging bidirectional information transfer and integrating neuromorphic computing elements.
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Affiliation(s)
- Grace A. Woods
- Department of Applied Physics, Stanford University, Stanford, California, 94305, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, 94305, USA
| | - Nicholas J. Rommelfanger
- Department of Applied Physics, Stanford University, Stanford, California, 94305, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, 94305, USA
| | - Guosong Hong
- Department of Materials Science and Engineering, Stanford University, Stanford, California, 94305, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, California, 94305, USA
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8
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Campos ACP, Kikuchi DS, Paschoa AFN, Kuroki MA, Fonoff ET, Hamani C, Pagano RL, Hernandes MS. Unraveling the Role of Astrocytes in Subthalamic Nucleus Deep Brain Stimulation in a Parkinson's Disease Rat Model. Cell Mol Neurobiol 2020; 40:939-954. [PMID: 31939008 PMCID: PMC7295825 DOI: 10.1007/s10571-019-00784-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 12/31/2019] [Indexed: 12/13/2022]
Abstract
Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an effective therapeutic strategy for motor symptoms of Parkinson's disease (PD) when L-DOPA therapy induces disabling side effects. Classical inflammatory activation of glial cells is well established in PD, contributing to the progressive neurodegenerative state; however, the role of DBS in regulating the inflammatory response remains largely unknown. To understand the involvement of astrocytes in the mechanisms of action of DBS, we evaluated the effect of STN-DBS in regulating motor symptoms, astrocyte reactivity, and cytokine expression in a 6-OHDA-induced PD rat model. To mimic in vivo DBS, we investigate the effect of high-frequency stimulation (HFS) in cultured astrocytes regulating cytokine induction and NF-κB activation. We found that STN-DBS improved motor impairment, induced astrocytic hyperplasia, and reversed increased IFN-γ and IL-10 levels in the globus pallidus (GP) of lesioned rats. Moreover, HFS activated astrocytes and prevented TNF-α-induced increase of monocyte chemoattractant protein-1 (MCP-1) and NF-κB activation in vitro. Our results indicate that DBS/HFS may act as a regulator of the inflammatory response in PD states, attenuating classical activation of astrocytes and cytokine induction, potentially through its ability to regulate NF-κB activation. These findings may help us understand the role of astrocyte signaling in HFS, highlighting its possible relationship with the effectiveness of DBS in neurodegenerative disorders.
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Affiliation(s)
| | | | | | - Mayra Akemi Kuroki
- Division of Neuroscience, Hospital Sírio-Libanês, São Paulo, SP, 01308-060, Brazil
| | - Erich Talamoni Fonoff
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, 01246-903, Brazil
| | - Clement Hamani
- Sunnybrook Health Research Institute, Harquail Centre for Neuromodulation, Toronto, ON, M4N 3M5, Canada
| | - Rosana Lima Pagano
- Division of Neuroscience, Hospital Sírio-Libanês, São Paulo, SP, 01308-060, Brazil.
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Patel SR, Lieber CM. Precision electronic medicine in the brain. Nat Biotechnol 2019; 37:1007-1012. [PMID: 31477925 PMCID: PMC6741780 DOI: 10.1038/s41587-019-0234-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Accepted: 07/23/2019] [Indexed: 02/06/2023]
Abstract
Periodically throughout history developments from adjacent fields of science and technology reach a tipping point where together they produce unparalleled advances, such as the Allen Brain Atlas and the Human Genome Project. Today, research focused at the interface between the nervous system and electronics is not only leading to advances in fundamental neuroscience, but also unlocking the potential of implants capable of cellular-level therapeutic targeting. Ultimately, these personalized electronic therapies will provide new treatment modalities for neurodegenerative and neuropsychiatric illness; powerful control of prosthetics for restorative function in degenerative diseases, trauma and amputation; and even augmentation of human cognition. Overall, we believe that emerging advances in tissue-like electronics will enable minimally invasive devices capable of establishing a stable long-term cellular neural interface and providing long-term treatment for chronic neurological conditions.
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Affiliation(s)
- Shaun R Patel
- McCance Center for Brain Health, Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Charles M Lieber
- Department of Chemistry and Chemical Biology, Center for Brain Science, and John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
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10
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Abstract
Neural recording electrode technologies have contributed considerably to neuroscience by enabling the extracellular detection of low-frequency local field potential oscillations and high-frequency action potentials of single units. Nevertheless, several long-standing limitations exist, including low multiplexity, deleterious chronic immune responses and long-term recording instability. Driven by initiatives encouraging the generation of novel neurotechnologies and the maturation of technologies to fabricate high-density electronics, novel electrode technologies are emerging. Here, we provide an overview of recently developed neural recording electrode technologies with high spatial integration, long-term stability and multiple functionalities. We describe how these emergent neurotechnologies can approach the ultimate goal of illuminating chronic brain activity with minimal disruption of the neural environment, thereby providing unprecedented opportunities for neuroscience research in the future.
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Affiliation(s)
- Guosong Hong
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA
- Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA
| | - Charles M Lieber
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Center for Brain Science, Harvard University, Cambridge, MA, USA.
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
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11
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Aplin FP, Fridman GY. Implantable Direct Current Neural Modulation: Theory, Feasibility, and Efficacy. Front Neurosci 2019; 13:379. [PMID: 31057361 PMCID: PMC6482222 DOI: 10.3389/fnins.2019.00379] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 04/02/2019] [Indexed: 12/25/2022] Open
Abstract
Implantable neuroprostheses such as cochlear implants, deep brain stimulators, spinal cord stimulators, and retinal implants use charge-balanced alternating current (AC) pulses to recover delivered charge and thus mitigate toxicity from electrochemical reactions occurring at the metal-tissue interface. At low pulse rates, these short duration pulses have the effect of evoking spikes in neural tissue in a phase-locked fashion. When the therapeutic goal is to suppress neural activity, implants typically work indirectly by delivering excitation to populations of neurons that then inhibit the target neurons, or by delivering very high pulse rates that suffer from a number of undesirable side effects. Direct current (DC) neural modulation is an alternative methodology that can directly modulate extracellular membrane potential. This neuromodulation paradigm can excite or inhibit neurons in a graded fashion while maintaining their stochastic firing patterns. DC can also sensitize or desensitize neurons to input. When applied to a population of neurons, DC can modulate synaptic connectivity. Because DC delivered to metal electrodes inherently violates safe charge injection criteria, its use has not been explored for practical applicability of DC-based neural implants. Recently, several new technologies and strategies have been proposed that address this safety criteria and deliver ionic-based direct current (iDC). This, along with the increased understanding of the mechanisms behind the transcutaneous DC-based modulation of neural targets, has caused a resurgence of interest in the interaction between iDC and neural tissue both in the central and the peripheral nervous system. In this review we assess the feasibility of in-vivo iDC delivery as a form of neural modulation. We present the current understanding of DC/neural interaction. We explore the different design methodologies and technologies that attempt to safely deliver iDC to neural tissue and assess the scope of application for direct current modulation as a form of neuroprosthetic treatment in disease. Finally, we examine the safety implications of long duration iDC delivery. We conclude that DC-based neural implants are a promising new modulation technology that could benefit from further chronic safety assessments and a better understanding of the basic biological and biophysical mechanisms that underpin DC-mediated neural modulation.
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Affiliation(s)
- Felix P Aplin
- Department of Otolaryngology Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States
| | - Gene Y Fridman
- Department of Otolaryngology Head and Neck Surgery, Johns Hopkins University, Baltimore, MD, United States.,Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, United States.,Department of Electrical and Computer Engineering, Johns Hopkins University, Baltimore, MD, United States
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12
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Hong G, Viveros RD, Zwang TJ, Yang X, Lieber CM. Tissue-like Neural Probes for Understanding and Modulating the Brain. Biochemistry 2018; 57:3995-4004. [PMID: 29529359 PMCID: PMC6039269 DOI: 10.1021/acs.biochem.8b00122] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Electrophysiology tools have contributed substantially to understanding brain function, yet the capabilities of conventional electrophysiology probes have remained limited in key ways because of large structural and mechanical mismatches with respect to neural tissue. In this Perspective, we discuss how the general goal of probe design in biochemistry, that the probe or label have a minimal impact on the properties and function of the system being studied, can be realized by minimizing structural, mechanical, and topological differences between neural probes and brain tissue, thus leading to a new paradigm of tissue-like mesh electronics. The unique properties and capabilities of the tissue-like mesh electronics as well as future opportunities are summarized. First, we discuss the design of an ultraflexible and open mesh structure of electronics that is tissue-like and can be delivered in the brain via minimally invasive syringe injection like molecular and macromolecular pharmaceuticals. Second, we describe the unprecedented tissue healing without chronic immune response that leads to seamless three-dimensional integration with a natural distribution of neurons and other key cells through these tissue-like probes. These unique characteristics lead to unmatched stable long-term, multiplexed mapping and modulation of neural circuits at the single-neuron level on a year time scale. Last, we offer insights on several exciting future directions for the tissue-like electronics paradigm that capitalize on their unique properties to explore biochemical interactions and signaling in a "natural" brain environment.
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Affiliation(s)
- Guosong Hong
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Robert D. Viveros
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Theodore J. Zwang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Xiao Yang
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
| | - Charles M. Lieber
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, USA
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA
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Evers MM, Miniarikova J, Juhas S, Vallès A, Bohuslavova B, Juhasova J, Skalnikova HK, Vodicka P, Valekova I, Brouwers C, Blits B, Lubelski J, Kovarova H, Ellederova Z, van Deventer SJ, Petry H, Motlik J, Konstantinova P. AAV5-miHTT Gene Therapy Demonstrates Broad Distribution and Strong Human Mutant Huntingtin Lowering in a Huntington's Disease Minipig Model. Mol Ther 2018; 26:2163-2177. [PMID: 30007561 PMCID: PMC6127509 DOI: 10.1016/j.ymthe.2018.06.021] [Citation(s) in RCA: 104] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 06/18/2018] [Accepted: 06/20/2018] [Indexed: 02/07/2023] Open
Abstract
Huntington’s disease (HD) is a fatal neurodegenerative disorder caused by a CAG trinucleotide repeat expansion in the huntingtin gene. Previously, we showed strong huntingtin reduction and prevention of neuronal dysfunction in HD rodents using an engineered microRNA targeting human huntingtin, delivered via adeno-associated virus (AAV) serotype 5 vector with a transgene encoding an engineered miRNA against HTT mRNA (AAV5-miHTT). One of the challenges of rodents as a model of neurodegenerative diseases is their relatively small brain, making successful translation to the HD patient difficult. This is particularly relevant for gene therapy approaches, where distribution achieved upon local administration into the parenchyma is likely dependent on brain size and structure. Here, we aimed to demonstrate the translation of huntingtin-lowering gene therapy to a large-animal brain. We investigated the feasibility, efficacy, and tolerability of one-time intracranial administration of AAV5-miHTT in the transgenic HD (tgHD) minipig model. We detected widespread dose-dependent distribution of AAV5-miHTT throughout the tgHD minipig brain that correlated with the engineered microRNA expression. Both human mutant huntingtin mRNA and protein were significantly reduced in all brain regions transduced by AAV5-miHTT. The combination of widespread vector distribution and extensive huntingtin lowering observed with AAV5-miHTT supports the translation of a huntingtin-lowering gene therapy for HD from preclinical studies into the clinic.
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Affiliation(s)
- Melvin M Evers
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands.
| | - Jana Miniarikova
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Stefan Juhas
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Astrid Vallès
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | | | - Jana Juhasova
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | | | - Petr Vodicka
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Ivona Valekova
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Cynthia Brouwers
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Bas Blits
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Jacek Lubelski
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Hana Kovarova
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Zdenka Ellederova
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Sander J van Deventer
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Harald Petry
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
| | - Jan Motlik
- Institute of Animal Physiology and Genetics, Libechov, Czech Republic
| | - Pavlina Konstantinova
- Department of Research & Development, uniQure biopharma B.V., Amsterdam, the Netherlands
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Sun FT, Arcot Desai S, Tcheng TK, Morrell MJ. Changes in the electrocorticogram after implantation of intracranial electrodes in humans: The implant effect. Clin Neurophysiol 2017; 129:676-686. [PMID: 29233473 DOI: 10.1016/j.clinph.2017.10.036] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/29/2017] [Accepted: 10/22/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Subacute and long-term electrocorticographic (ECoG) changes in ambulatory patients with depth and cortical strip electrodes were evaluated in order to determine the length of the implant effect. METHODS ECoG records were assessed in patients with medically intractable epilepsy who had depth and/or strip leads implanted in order to be treated with brain-responsive stimulation. Changes in total spectral power, band-limited spectral power, and spike rate were assessed. RESULTS 121 patients participating in trials of the RNS® System had a total of 93994 ECoG records analyzed. Significant changes in total spectral power occurred from the first to second months after implantation, involving 55% of all ECoG channels (68% of strip and 47% of depth lead channels). Significant, but less pronounced, changes continued over the 2nd to 5th post-implant months, after which total power became more stable. Similar patterns of changes were observed within frequency bands and spike rate. CONCLUSIONS ECoG spectral power and spike rates are not stable in the first 5 months after implantation, presumably due to neurophysiological and electrode-tissue interface changes. SIGNIFICANCE ECoG data collected in the first 5 months after implantation of intracranial electrodes may not be fully representative of chronic cortical electrophysiology.
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Affiliation(s)
| | | | | | - Martha J Morrell
- NeuroPace, Inc., Mountain View, CA 94043, USA; Department of Neurology and Neurological Sciences, Stanford University, Palo Alto, CA 94305, USA
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Hadar R, Dong L, Del-Valle-Anton L, Guneykaya D, Voget M, Edemann-Callesen H, Schweibold R, Djodari-Irani A, Goetz T, Ewing S, Kettenmann H, Wolf SA, Winter C. Deep brain stimulation during early adolescence prevents microglial alterations in a model of maternal immune activation. Brain Behav Immun 2017; 63:71-80. [PMID: 27939248 DOI: 10.1016/j.bbi.2016.12.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 11/23/2016] [Accepted: 12/05/2016] [Indexed: 11/25/2022] Open
Abstract
In recent years schizophrenia has been recognized as a neurodevelopmental disorder likely involving a perinatal insult progressively affecting brain development. The poly I:C maternal immune activation (MIA) rodent model is considered as a neurodevelopmental model of schizophrenia. Using this model we and others demonstrated the association between neuroinflammation in the form of altered microglia and a schizophrenia-like endophenotype. Therapeutic intervention using the anti-inflammatory drug minocycline affected altered microglia activation and was successful in the adult offspring. However, less is known about the effect of preventive therapeutic strategies on microglia properties. Previously we found that deep brain stimulation of the medial prefrontal cortex applied pre-symptomatically to adolescence MIA rats prevented the manifestation of behavioral and structural deficits in adult rats. We here studied the effects of deep brain stimulation during adolescence on microglia properties in adulthood. We found that in the hippocampus and nucleus accumbens, but not in the medial prefrontal cortex, microglial density and soma size were increased in MIA rats. Pro-inflammatory cytokine mRNA was unchanged in all brain areas before and after implantation and stimulation. Stimulation of either the medial prefrontal cortex or the nucleus accumbens normalized microglia density and soma size in main projection areas including the hippocampus and in the area around the electrode implantation. We conclude that in parallel to an alleviation of the symptoms in the rat MIA model, deep brain stimulation has the potential to prevent the neuroinflammatory component in this disease.
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Affiliation(s)
- Ravit Hadar
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany
| | - Le Dong
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Lucia Del-Valle-Anton
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Dilansu Guneykaya
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Mareike Voget
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany; International Graduate Program Medical Neurosciences, Charité - Universitaetsmedizin Berlin, Germany
| | - Henriette Edemann-Callesen
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany; International Graduate Program Medical Neurosciences, Charité - Universitaetsmedizin Berlin, Germany
| | - Regina Schweibold
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Anais Djodari-Irani
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Thomas Goetz
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany
| | - Samuel Ewing
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany
| | - Helmut Kettenmann
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Susanne A Wolf
- Cellular Neuroscience, Max-Delbrueck-Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
| | - Christine Winter
- Department of Psychiatry and Psychotherapy, Medical Faculty Carl Gustav Carus, Technische Universitaet Dresden, Germany
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Orlowski D, Michalis A, Glud AN, Korshøj AR, Fitting LM, Mikkelsen TW, Mercanzini A, Jordan A, Dransart A, Sørensen JCH. Brain Tissue Reaction to Deep Brain Stimulation-A Longitudinal Study of DBS in the Goettingen Minipig. Neuromodulation 2017; 20:417-423. [PMID: 28220987 DOI: 10.1111/ner.12576] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/21/2016] [Accepted: 12/06/2016] [Indexed: 02/03/2023]
Abstract
OBJECTIVES The use of Deep Brain Stimulation (DBS) in treatment of various brain disorders is constantly growing; however, the number of studies of the reaction of the brain tissue toward implanted leads is still limited. Therefore, the aim of our study was to analyze the impact of DBS leads on brain tissue in a large animal model using minipigs. METHODS Twelve female animals, one control and eleven with bilaterally implanted DBS electrodes were used in our experiment. 3, 6, and 12 months after implantation the animals were sacrificed, perfused and the brains were removed. Tissue blocks containing the lead tracks were dissected, frozen, sectioned into 40 µm sections and stained using Nissl and Eosin, anti-GFAPab or Isolectin. The tissue reaction was analyzed at five levels, following from the distal lead tip, to compare tissue response in stimulated and nonstimulated areas: four segments along each level of electrodes, and the fifth level lying outside the electrode area (control area). The sections were described both qualitatively and quantitatively. Quantitative assessment of the reaction to the implanted electrode was based on the measurement of the area covered by the staining and the thickness of the glial scar. RESULTS AND CONCLUSIONS Tissue reaction was, on average, limited to distance of 500 μm from the lead track. The tissue response after 12 months was weaker than after 6 months confirming that it stabilizes over a time. There was no histological evidence that the stimulated part of the electrode triggered different tissue response than its nonstimulated part.
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Affiliation(s)
- Dariusz Orlowski
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | | | - Andreas N Glud
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Anders R Korshøj
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Lise M Fitting
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | - Trine W Mikkelsen
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
| | | | - Alain Jordan
- Aleva Neurotherapeutics SA, Lausanne, Switzerland
| | | | - Jens C H Sørensen
- CENSE group, Department of Neurosurgery, Aarhus University Hospital; Department of Clinical Medicine, Faculty of Health, Aarhus University, Aarhus, Denmark
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Liang C, Xu Y, Zheng D, Sun X, Xu Q, Duan D. RNAi-mediated silencing of HLA A2 suppressed acute rejection against human fibroblast xenografts in the striatum of 6-OHDA lesioned rats. J Neuroimmunol 2016; 297:28-37. [PMID: 27397073 DOI: 10.1016/j.jneuroim.2016.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 04/11/2016] [Accepted: 05/02/2016] [Indexed: 02/06/2023]
Abstract
Major histocompatibility complex class l (MHC I) molecules play a role in determining whether transplanted cells will be accepted or rejected, and masking of MHC I on donor cells has been found useful for immunoprotection of neural xenografts. In the present study, primary human embryonic lung fibroblasts (HELF), HELF treated with lentivirus-mediated small interfering RNAs (siRNAs) targeting human leukocyte antigen A2 (HLA A2, MHC I in humans) (siHELF), and rat embryonic lung fibroblasts (RELF) were stereotaxically grafted into the striatum of 6-hydroxydopamine lesioned rats to explore whether knockdown of HLA A2 could reduce host immune responses against xenografts. Before lentiviral infection, the cells were transduced with retroviruses harboring tyrosine hydroxylase cDNA. Knockdown of HLA A2 protein was examined by Western blotting. The immune responses (the number of CD4 and CD8 T-cells in the brain and peripheral blood), glial reaction, and survival of human fibroblasts were quantitatively evaluated by flow cytometry and immunohistochemistry at 4d, 2w, and 6w post-graft. Animal behaviors were assessed by counting apomorphine-induced rotations pre- and post-grafts. It was shown that a lower level of HLA A2 was observed in siHELF grafts than in HELF grafts, and knockdown of HLA A2 decreased rat immune responses, as indicated by less remarkable increases in the number of CD8 and CD4 T-cells in the brain and the ratio of CD4:CD8 T-cells in the peripheral blood in rats grafted with siHELF. Rats grafted with siHELF exhibited a significant improvement in motor asymmetry post-transplantation and a better survival of human fibroblasts at 2w. The increasing number of activated microglia and the decreasing number of astrocytes were found in three groups of rats post-implantation. These data suggested that RNAi-mediated knockdown of HLA A2 could suppress acute rejection against xenogeneic human cell transplants in the rat brain.
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Affiliation(s)
- Caixia Liang
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Yunzhi Xu
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Deyu Zheng
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Xiaohong Sun
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Qunyuan Xu
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
| | - Deyi Duan
- Department of Neurobiology, Beijing Center of Neural Regeneration and Repair, Beijing Institute for Brain Disorders, Laboratory of Neurodegenerative Disorders of the Ministry of Education, Capital Medical University, Beijing 100069, China
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Vedam-Mai V, Baradaran-Shoraka M, Reynolds BA, Okun MS. Tissue Response to Deep Brain Stimulation and Microlesion: A Comparative Study. Neuromodulation 2016; 19:451-8. [PMID: 27018335 PMCID: PMC4961567 DOI: 10.1111/ner.12406] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/16/2015] [Accepted: 01/12/2016] [Indexed: 01/14/2023]
Abstract
OBJECTIVES Deep brain stimulation (DBS) is used for a variety of movement disorders, including Parkinson's disease. There are several theories regarding the biology and mechanisms of action of DBS. Previously, we observed an up-regulation of neural progenitor cell proliferation in post-mortem tissue suggesting that DBS can influence cellular plasticity in regions beyond the site of stimulation. We wanted to support these observations and investigate the relationship if any, between DBS, neural progenitor cells, and microglia. METHODS We used naïve rats in this study for DBS electrode implantation, stimulation, and microlesions. We used immunohistochemistry techniques for labeling microglial and progenitor cells, and fluorescence microscopy for viewing and quantification of labeled cells. RESULTS We present data that demonstrates a reciprocal relationship of microglia and neural precursor cells in the presence of acute high frequency stimulation. In our hands, stimulated animals demonstrate significantly lower numbers of activated microglia (p = 0.026) when compared to microlesion and sham animals. The subthalamic region surrounding the DBS stimulating electrode reveals a significant increase in the number of neural precursor cells expressing cell cycle markers, plasticity and precursor cell markers (Ki67; p = 0.0013, MCM2; p = 0.0002). INTERPRETATION We conclude that in this animal model, acute DBS results in modest local progenitor cell proliferation and influenced the total number of activated microglia. This could be of clinical significance in patients with PD, as it is thought to progress via neuroinflammatory processes involving microglia, cytokines, and the complement system. Further studies are required to comprehend the behavior of microglia in different activation states and their ability to regulate adult neurogenesis under physiologic and pathologic conditions.
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Affiliation(s)
- Vinata Vedam-Mai
- Department of Neurosurgery, McKnight Brain Institute, University of FL, Gainesville, FL, USA.,Department of Neurology, UF Center for Movement Disorders and Restoration, Gainesville, FL, USA
| | | | - Brent A Reynolds
- Department of Neurosurgery, McKnight Brain Institute, University of FL, Gainesville, FL, USA
| | - Michael S Okun
- Movement Disorders & Neurorestoration, Gainesville, FL, USA
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Tamburrino A, Churchill MJ, Wan OW, Colino-Sanguino Y, Ippolito R, Bergstrand S, Wolf DA, Herz NJ, Sconce MD, Björklund A, Meshul CK, Decressac M. Cyclosporin promotes neurorestoration and cell replacement therapy in pre-clinical models of Parkinson's disease. Acta Neuropathol Commun 2015; 3:84. [PMID: 26666562 PMCID: PMC4678733 DOI: 10.1186/s40478-015-0263-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 12/03/2015] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND The early clinical trials using fetal ventral mesencephalic (VM) allografts in Parkinson's disease (PD) patients have shown efficacy (albeit not in all cases) and have paved the way for further development of cell replacement therapy strategies in PD. The preclinical work that led to these clinical trials used allografts of fetal VM tissue placed into 6-OHDA lesioned rats, while the patients received similar allografts under cover of immunosuppression in an α-synuclein disease state. Thus developing models that more faithfully replicate the clinical scenario would be a useful tool for the translation of such cell-based therapies to the clinic. RESULTS Here, we show that while providing functional recovery, transplantation of fetal dopamine neurons into the AAV-α-synuclein rat model of PD resulted in smaller-sized grafts as compared to similar grafts placed into the 6-OHDA-lesioned striatum. Additionally, we found that cyclosporin treatment was able to promote the survival of the transplanted cells in this allografted state and surprisingly also provided therapeutic benefit in sham-operated animals. We demonstrated that delayed cyclosporin treatment afforded neurorestoration in three complementary models of PD including the Thy1-α-synuclein transgenic mouse, a novel AAV-α-synuclein mouse model, and the MPTP mouse model. We then explored the mechanisms for this benefit of cyclosporin and found it was mediated by both cell-autonomous mechanisms and non-cell autonomous mechanisms. CONCLUSION This study provides compelling evidence in favor for the use of immunosuppression in all grafted PD patients receiving cell replacement therapy, regardless of the immunological mismatch between donor and host cells, and also suggests that cyclosporine treatment itself may act as a disease-modifying therapy in all PD patients.
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Affiliation(s)
- Anna Tamburrino
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Madeline J Churchill
- Veterans Hospital/Research Services/Portland and Department of Behavioral Neuroscience Oregon Health &, Science University, Portland, OR, USA
| | - Oi W Wan
- Wallenberg Neuroscience Center, Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Yolanda Colino-Sanguino
- Wallenberg Neuroscience Center, Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Rossana Ippolito
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Sofie Bergstrand
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Daniel A Wolf
- Wallenberg Neuroscience Center, Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Niculin J Herz
- Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute, Houston, USA
| | - Michelle D Sconce
- Veterans Hospital/Research Services/Portland and Department of Behavioral Neuroscience Oregon Health &, Science University, Portland, OR, USA
| | - Anders Björklund
- Wallenberg Neuroscience Center, Department of Experimental Medical Sciences, Lund University, Lund, Sweden
| | - Charles K Meshul
- Veterans Hospital/Research Services/Portland and Department of Behavioral Neuroscience Oregon Health &, Science University, Portland, OR, USA
| | - Mickael Decressac
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.
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Kubik LL, Philbert MA. The role of astrocyte mitochondria in differential regional susceptibility to environmental neurotoxicants: tools for understanding neurodegeneration. Toxicol Sci 2015; 144:7-16. [PMID: 25740792 DOI: 10.1093/toxsci/kfu254] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
In recent decades, there has been a significant expansion in our understanding of the role of astrocytes in neuroprotection, including spatial buffering of extracellular ions, secretion of metabolic coenzymes, and synaptic regulation. Astrocytic neuroprotective functions require energy, and therefore require a network of functional mitochondria. Disturbances to astrocytic mitochondrial homeostasis and their ability to produce ATP can negatively impact neural function. Perturbations in astrocyte mitochondrial function may accrue as the result of physiological aging processes or as a consequence of neurotoxicant exposure. Hydrophobic environmental neurotoxicants, such as 1,3-dinitrobenzene and α-chlorohydrin, cause regionally specific spongiform lesions mimicking energy deprivation syndromes. Astrocyte involvement includes mitochondrial damage that either precedes or is accompanied by neuronal damage. Similarly, environmental neurotoxicants that are implicated in the etiology of age-related neurodegenerative conditions cause regionally specific damage in the brain. Based on the regioselective nature of age-related neurodegenerative lesions, chemically induced models of regioselective lesions targeting astrocyte mitochondria can provide insight into age-related susceptibilities in astrocyte mitochondria. Most of the available research to date focuses on neuronal damage in cases of age-related neurodegeneration; however, there is a body of evidence that supports a central mechanistic role for astrocyte mitochondria in the expression of neural injury. Regional susceptibility to neuronal damage induced by aging by exposure to neurotoxicants may be a reflection of highly variable regional energy requirements. This review identifies region-specific vulnerabilities in astrocyte mitochondria in examples of exposure to neurotoxicants and in age-related neurodegeneration.
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Affiliation(s)
- Laura L Kubik
- Toxicology Program, Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109
| | - Martin A Philbert
- Toxicology Program, Department of Environmental Health Sciences, School of Public Health, University of Michigan, Ann Arbor, MI 48109
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Yan JQ, Sun JC, Zhai MM, Cheng LN, Bai XL, Feng CL. Lovastatin induces neuroprotection by inhibiting inflammatory cytokines in 6-hydroxydopamine treated microglia cells. Int J Clin Exp Med 2015; 8:9030-9037. [PMID: 26309556 PMCID: PMC4538109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Accepted: 06/05/2015] [Indexed: 06/04/2023]
Abstract
PURPOSE/AIM This study aims to investigate the impact of lovastatin on neuroinflammation in 6-OHDA-treated microglia cells. MATERIALS AND METHODS 6-Hydroxydopamine (6-OHDA)-treated microglia cells were used to investigate the neuroprotective nature of lovastatin. After incubation with 6-OHDA and/or lovastatin for 24 h, test kits were used to detect the levels of LDH and glutamate, which were released from PC12 cells exposed to different culture media. The mRNA levels of TNF-α, IL-6 and IL-1β were determined by RT-PCR and the protein levels were analyzed by Western blot. RESULTS LDH and glutamate levels in 6-OHDA-incubated PC12 cells increased, when compared with those in the controls, while incubation with lovastatin inhibited this elevation. The expression levels of TNF-α IL-6 and IL-1β were significantly upregulated after treatment with 6-OHDA. The 6-OHDA-stimulated mRNA and protein levels of TNF-α IL-6 and IL-1β were reduced by lovastatin. CONCLUSIONS Our results suggest that Lovastatin is able to induce neuroprotection by inhibiting inflammatory cytokines. The data provide direct evidence of the potential application of lovastatin for the treatment of neuroinflammatory diseases.
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Affiliation(s)
- Jun-Qiang Yan
- Department of Neurology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
| | - Jia-Chun Sun
- Department of Oncology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
| | - Ming-Ming Zhai
- Department of Neurology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
| | - Li-Niu Cheng
- Department of Neurology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
| | - Xiao-Li Bai
- Department of Neurology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
| | - Cui-Ling Feng
- Department of Neurology, The First Affiliated Hospital of Henan University of Science and Technology Jinghua Road 24, Luoyang 471003, Henan, P.R. China
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Striatal Injury with 6-OHDA Transiently Increases Cerebrospinal GFAP and S100B. Neural Plast 2015; 2015:387028. [PMID: 26090233 PMCID: PMC4451977 DOI: 10.1155/2015/387028] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 03/02/2015] [Accepted: 03/03/2015] [Indexed: 12/27/2022] Open
Abstract
Both glial fibrillary acidic protein (GFAP) and S100B have been used as markers of astroglial plasticity, particularly in brain injury; however, they do not necessarily change in the same time frame or direction. Herein, we induced a Parkinson's disease (PD) model via a 6-OHDA intrastriatal injection in rats and investigated the changes in GFAP and S100B using ELISA in the substantia nigra (SN), striatum, and cerebrospinal fluid on the 1st, 7th, and 21st days following the injection. The model was validated using measurements of rotational behaviour induced by methylphenidate and tyrosine hydroxylase in the dopaminergic pathway. To our knowledge, this is the first measurement of cerebrospinal fluid S100B and GFAP in the 6-OHDA model of PD. Gliosis (based on a GFAP increase) was identified in the striatum, but not in the SN. We identified a transitory increment of cerebrospinal fluid S100B and GFAP on the 1st and 7th days, respectively. This initial change in cerebrospinal fluid S100B was apparently related to the mechanical lesion. However, the 6-OHDA-induced S100B secretion was confirmed in astrocyte cultures. Current data reinforce the idea that glial changes precede neuronal damage in PD; however, these findings also indicate that caution is necessary regarding the interpretation of data in this PD model.
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Arsenault D, Drouin-Ouellet J, Saint-Pierre M, Petrou P, Dubois M, Kriz J, Barker RA, Cicchetti A, Cicchetti F. A novel combinational approach of microstimulation and bioluminescence imaging to study the mechanisms of action of cerebral electrical stimulation in mice. J Physiol 2015; 593:2257-78. [PMID: 25653107 DOI: 10.1113/jphysiol.2014.287243] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 01/30/2015] [Indexed: 12/12/2022] Open
Abstract
Deep brain stimulation (DBS) is used to treat a number of neurological conditions and is currently being tested to intervene in neuropsychiatric conditions. However, a better understanding of how it works would ensure that side effects could be minimized and benefits optimized. We have thus developed a unique device to perform brain stimulation (BS) in mice and to address fundamental issues related to this methodology in the pre-clinical setting. This new microstimulator prototype was specifically designed to allow simultaneous live bioluminescence imaging of the mouse brain, allowing real time assessment of the impact of stimulation on cerebral tissue. We validated the authenticity of this tool in vivo by analysing the expression of toll-like receptor 2 (TLR2), corresponding to the microglial response, in the stimulated brain regions of TLR2-fluc-GFP transgenic mice, which we further corroborated with post-mortem analyses in these animals as well as in human brains of patients who underwent DBS to treat their Parkinson's disease. In the present study, we report on the development of the first BS device that allows for simultaneous live in vivo imaging in mice. This tool opens up a whole new range of possibilities that allow a better understanding of BS and how to optimize its effects through its use in murine models of disease.
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Affiliation(s)
- Dany Arsenault
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada
| | - Janelle Drouin-Ouellet
- John van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, UK
| | - Martine Saint-Pierre
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada
| | - Petros Petrou
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada
| | - Marilyn Dubois
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada
| | - Jasna Kriz
- Département de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada.,Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada
| | - Roger A Barker
- John van Geest Centre for Brain Repair, Department of Clinical Neuroscience, University of Cambridge, Cambridge, UK
| | - Antonio Cicchetti
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada
| | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec (CHUQ), Axe Neurosciences, Québec, QC, Canada.,Département de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada
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Pelletier SJ, Lagacé M, St-Amour I, Arsenault D, Cisbani G, Chabrat A, Fecteau S, Lévesque M, Cicchetti F. The morphological and molecular changes of brain cells exposed to direct current electric field stimulation. Int J Neuropsychopharmacol 2015; 18:pyu090. [PMID: 25522422 PMCID: PMC4376545 DOI: 10.1093/ijnp/pyu090] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The application of low-intensity direct current electric fields has been experimentally used in the clinic to treat a number of brain disorders, predominantly using transcranial direct current stimulation approaches. However, the cellular and molecular changes induced by such treatment remain largely unknown. METHODS Here, we tested various intensities of direct current electric fields (0, 25, 50, and 100V/m) in a well-controlled in vitro environment in order to investigate the responses of neurons, microglia, and astrocytes to this type of stimulation. This included morphological assessments of the cells, viability, as well as shape and fiber outgrowth relative to the orientation of the direct current electric field. We also undertook enzyme-linked immunosorbent assays and western immunoblotting to identify which molecular pathways were affected by direct current electric fields. RESULTS In response to direct current electric field, neurons developed an elongated cell body shape with neurite outgrowth that was associated with a significant increase in growth associated protein-43. Fetal midbrain dopaminergic explants grown in a collagen gel matrix also showed a reorientation of their neurites towards the cathode. BV2 microglial cells adopted distinct morphological changes with an increase in cyclooxygenase-2 expression, but these were dependent on whether they had already been activated with lipopolysaccharide. Finally, astrocytes displayed elongated cell bodies with cellular filopodia that were oriented perpendicularly to the direct current electric field. CONCLUSION We show that cells of the central nervous system can respond to direct current electric fields both in terms of their morphological shape and molecular expression of certain proteins, and this in turn can help us to begin understand the mechanisms underlying the clinical benefits of direct current electric field.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Francesca Cicchetti
- Centre de Recherche du CHU de Québec, Axe Neuroscience, Québec, QC, Canada (Mr Pelletier, Ms Lagacé, Drs St-Amour, Arsenault, Cisbani, and Cicchetti); Département de Psychiatrie et Neurosciences, Université Laval, Québec, QC, Canada (Drs Lévesque and Cicchetti); Centre de recherche de l'Institut Universitaire en Santé Mentale de Québec, Québec, QC, Canada (Ms Chabrat and Dr Lévesque); Laboratory of Canada Research Chair in Cognitive Neuroscience, Centre Interdisciplinaire de Recherche en Réadaptation et Intégration Sociale, Centre de Recherche de l'Institut Universitaire en Santé Mentale de Québec, Université Laval, Canada (Dr Fecteau); Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Cambridge, MA (Dr Fecteau).
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Jha SK, Jha NK, Kar R, Ambasta RK, Kumar P. p38 MAPK and PI3K/AKT Signalling Cascades inParkinson's Disease. INTERNATIONAL JOURNAL OF MOLECULAR AND CELLULAR MEDICINE 2015; 4:67-86. [PMID: 26261796 PMCID: PMC4499569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Revised: 02/02/2015] [Accepted: 03/14/2015] [Indexed: 11/18/2022]
Abstract
Parkinson's disease (PD) is a chronic neurodegenerative condition which has the second largest incidence rate among all other neurodegenerative disorders barring Alzheimer's disease (AD). Currently there is no cure and researchers continue to probe the therapeutic prospect in cell cultures and animal models of PD. Out of the several factors contributing to PD prognosis, the role of p38 MAPK (Mitogen activated protein-kinase) and PI3K/AKT signalling module in PD brains is crucial because the impaired balance between the pro- apoptotic and anti-apoptotic pathways trigger unwanted phenotypes such as microglia activation, neuroinflammation, oxidative stress and apoptosis. These factors continue challenging the brain homeostasis in initial stages thereby essentially assisting the dopaminergic (DA) neurons towards progressive degeneration in PD. Neurotherapeutics against PD shall then be targeted against the misregulated accomplices of the p38 and PI3K/AKT cascades. In this review, we have outlined many such established mechanisms involving the p38 MAPK and PI3K/AKT pathways which can offer therapeutic windows for the rectification of aberrant DA neuronal dynamics in PD brains.
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Affiliation(s)
- Saurabh Kumar Jha
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi, India.
| | - Niraj Kumar Jha
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi, India.
| | - Rohan Kar
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi, India.
| | - Rashmi K Ambasta
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi, India.
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly DCE), Delhi, India.,Department of Neurology, Tufts University School of Medicine, Boston, MA (USA).,Corresponding author: Molecular Neuroscience and Functional Genomics Laboratory, Delhi Technological University (Formerly DCE), Delhi, India. E-mail: ;
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Barker RA, Cicchetti F. Neurodegenerative disorders: the Glia way forward. Front Pharmacol 2014; 5:157. [PMID: 25076908 PMCID: PMC4097031 DOI: 10.3389/fphar.2014.00157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 06/18/2014] [Indexed: 11/24/2022] Open
Affiliation(s)
- Roger A Barker
- Department of Clinical Neuroscience, John van Geest Centre for Brain Repair, University of Cambridge Cambridge, UK
| | - Francesca Cicchetti
- Axe Neurosciences, Department of Psychiatry and Neurosciences, Centre de Recherche du CHU de Québec, Université Laval Québec, QC, Canada
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