51
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Hsieh TH, Lee HHC, Hameed MQ, Pascual-Leone A, Hensch TK, Rotenberg A. Trajectory of Parvalbumin Cell Impairment and Loss of Cortical Inhibition in Traumatic Brain Injury. Cereb Cortex 2018; 27:5509-5524. [PMID: 27909008 DOI: 10.1093/cercor/bhw318] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 09/21/2016] [Indexed: 11/13/2022] Open
Abstract
Many neuropsychiatric symptoms that follow traumatic brain injury (TBI), including mood disorders, sleep disturbance, chronic pain, and posttraumatic epilepsy (PTE) are attributable to compromised cortical inhibition. However, the temporal trajectory of cortical inhibition loss and its underlying mechanisms are not known. Using paired-pulse transcranial magnetic stimulation (ppTMS) and immunohistochemistry, we tracked functional and cellular changes of cortical inhibitory network elements after fluid-percussion injury (FPI) in rats. ppTMS revealed a progressive loss of cortical inhibition as early as 2 weeks after FPI. This profile paralleled the increasing levels of cortical oxidative stress, which was accompanied by a gradual loss of parvalbumin (PV) immunoreactivity in perilesional cortex. Preceding the PV loss, we identified a degradation of the perineuronal net (PNN)-a specialized extracellular structure enwrapping cortical PV-positive (PV+) inhibitory interneurons which binds the PV+ cell maintenance factor, Otx2. The trajectory of these impairments underlies the reduced inhibitory tone, which can contribute to posttraumatic neurological conditions, such as PTE. Taken together, our results highlight the use of ppTMS as a biomarker to track the course of cortical inhibitory dysfunction post-TBI. Moreover, the neuroprotective role of PNNs on PV+ cell function suggests antioxidant treatment or Otx2 enhancement as a promising prophylaxis for post-TBI symptoms.
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Affiliation(s)
- Tsung-Hsun Hsieh
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Department of Physical Therapy and Graduate Institute of Rehabilitation Science, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.,Neuroscience Research Center, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan 33305, Taiwan
| | - Henry Hing Cheong Lee
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mustafa Qadir Hameed
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Department of Neurosurgery, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Alvaro Pascual-Leone
- Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Takao K Hensch
- Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Department of Molecular and Cellular Biology, Center for Brain Science, Harvard University, MA 02138, USA
| | - Alexander Rotenberg
- Neuromodulation Program, Division of Epilepsy and Clinical Neurophysiology, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Department of Neurology, F.M. Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Berenson-Allen Center for Noninvasive Brain Stimulation, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
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52
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Rogers SL, Rankin-Gee E, Risbud RM, Porter BE, Marsh ED. Normal Development of the Perineuronal Net in Humans; In Patients with and without Epilepsy. Neuroscience 2018; 384:350-360. [PMID: 29885523 DOI: 10.1016/j.neuroscience.2018.05.039] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 05/16/2018] [Accepted: 05/24/2018] [Indexed: 02/01/2023]
Abstract
The perineuronal net (PN), a highly organized extracellular matrix structure, is believed to play an important role in synaptic function, including maturation and stabilization. In addition to its role in restricting plasticity, alterations in the PN are implicated in disorders such as epilepsy and schizophrenia. However, the time course of PN development is not known in humans. Therefore we set out to document the developmental timeline of the PN formation in humans in 14 frontal and hippocampal specimens from donors aged 27 days to 31 years old. Using immunohistochemistry and western blotting, we demonstrate that the PN begins to form as early as the second month of life but does not reach its robust, mature appearance until around 8 years of age, though aggrecan cleavage products are observed prior to this. A similar developmental time course was observed in specimens from epilepsy patients. Our data suggest that aggrecan is present early in development but the structured PN develops throughout early childhood, similar to what has been observed in rodents. This timeline provides information for future pathological studies on the role of the PN in disease and an additional parallel between human and rodent development.
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Affiliation(s)
- Stephanie L Rogers
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Elyse Rankin-Gee
- Department of Neurology, Stanford University School of Medicine, Palo Alto, CA 94305, United States
| | - Rashmi M Risbud
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States
| | - Brenda E Porter
- Department of Neurology, Stanford University School of Medicine, Palo Alto, CA 94305, United States
| | - Eric D Marsh
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, United States; Departments of Neurology and Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, United States.
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53
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Wang F, Chen F, Wang G, Wei S, Fang F, Kang D, Lin Y. Rapamycin provides anti-epileptogenic effect in a rat model of post-traumatic epilepsy via deactivation of mTOR signaling pathway. Exp Ther Med 2018; 15:4763-4770. [PMID: 29904395 PMCID: PMC5996717 DOI: 10.3892/etm.2018.6004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 03/05/2018] [Indexed: 12/19/2022] Open
Abstract
The mammalian target of rapamycin (mTOR) signaling pathway has attracted much attention in recent years. However, the contribution of mTOR activation to the development of post-traumatic epilepsy (PTE) remains largely unknown. The purpose of the present study was to investigate the activation of mTOR signaling in a rat model of FeCl2-induced PTE, and to explore the potential effect of its specific inhibitor rapamycin. The results indicated that the expression levels of p-mTOR and p-P70S6K, the overactivation biomarkers of mTOR signaling, increased significantly in hippocampal and perilesional cortex following PTE induction. Notably, they were significantly decreased in the aformementioned brain regions following rapamycin treatment. Furthermore, the frequency and number of behavioral seizures and epileptic brain injury were also greatly reduced. These results suggest that hyperactivation of the mTOR signaling pathway is a crucial mechanism of PTE development, and it may be considered a novel therapeutic target for PTE treatment.
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Affiliation(s)
- Feng Wang
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Fuxiang Chen
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Genbo Wang
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Shushan Wei
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Fu Fang
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Dezhi Kang
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
| | - Yuanxiang Lin
- Department of Neurosurgery, The First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350005, P.R. China
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54
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Koh CH, Pronin S, Hughes M. Chondroitinase ABC for neurological recovery after acute brain injury: systematic review and meta-analyses of preclinical studies. Brain Inj 2018; 32:715-729. [PMID: 29436856 DOI: 10.1080/02699052.2018.1438665] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVES Damage to critical brain regions causes deficits in important neurological functions. Chondroitinase ABC (ChABC) has been shown to promote neuroplasticity and may ameliorate neurological deficits caused by disease or trauma. This systematic review identifies and evaluates preclinical studies of ChABC as a treatment for acute brain injury. METHODS Four databases were searched for studies relating to ChABC and brain or brain injuries. Controlled studies in mammals with acute brain injuries treated with ChABC were included in meta-analyses of neurobehavioural outcomes. Means and standard deviations from the fifth day of treatment were extracted, and normalised mean differences were calculated. RESULTS Of 775 identified records, 16 studies administered ChABC after acute brain injury, of which 9 reported neurobehavioural outcomes. The estimated treatment effect on neurological recovery over the duration of included studies was 49.4% (CI: 30.3-68.4% with Hartung-Knapp-Sidik-Jonkman adjustment, p = 0.0002). The mechanisms of action may involve decreasing astroglial scar formation, promoting neuronal sprouting, and selective synaptic strengthening of sprouting neurites and activated neural pathways. CONCLUSIONS The summary of published evidence suggests that ChABC treatment is effective in improving neurological outcomes in preclinical models of acute brain injury. However, more studies are needed for better assessment of the specific translational potential of ChABC. ABBREVIATIONS AVM - Arteriovenous Malformation; ChABC - Chondroitinase ABC; CI - Confidence Interval; CSPG - Chondroitin Sulphate Proteoglycans; HKSJ - Hartung-Knapp-Sidik-Jonkman; MCA - Middle Cerebral Artery; NMD - Normalised Mean Difference; NSPC - Neural Stem/Progenitor Cells; PI - Prediction Interval; SD - Standard Deviation; SMD - Standardised Mean Difference; TBI - Traumatic Brain Injury.
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Affiliation(s)
- Chan Hee Koh
- a Edinburgh Medical School , University of Edinburgh , Edinburgh , United Kingdom
| | - Savva Pronin
- a Edinburgh Medical School , University of Edinburgh , Edinburgh , United Kingdom
| | - Mark Hughes
- b Translational Neurosurgery Unit , Centre for Clinical Brain Sciences, University of Edinburgh , Edinburgh , United Kingdom
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55
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Kielbinski M, Gzielo K, Soltys Z. Review: Roles for astrocytes in epilepsy: insights from malformations of cortical development. Neuropathol Appl Neurobiol 2018; 42:593-606. [PMID: 27257021 DOI: 10.1111/nan.12331] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 05/25/2016] [Accepted: 06/03/2016] [Indexed: 12/25/2022]
Abstract
Malformations of cortical development (MCDs), such as cortical dysplasia and tuberous sclerosis complex, are common causes of intractable epilepsy, especially in paediatric patients. Recently, mounting evidence points to a common pathology of these disorders. Hyperactivation of mammalian target of rapamycin (mTOR) has been proposed as a central mechanism in most, if not all, MCDs. The transition from mTOR hyperactivation and cellular abnormalities to large-scale functional changes and seizure is, however, not fully understood. In this article we set out to review currently available information regarding MCD pathology, focusing on glial cells - especially astrocytes - and their interactions with the brain vascular system. A large body of evidence points to these elements as potential targets in MCD. Here, we attempt to provide a review of this evidence and propose some hypotheses regarding the possible chain of events linking primary glial dysfunction and epilepsy. We focus on extracellular matrix remodelling, blood-brain barrier leakage and failure of astrocyte-dependent removal of extracellular debris. We posit that the failure of these systems results in a chronically pro-inflammatory environment, maintaining local astrocytes in a state of gliosis, with increased susceptibility to seizures as a consequence.
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Affiliation(s)
- M Kielbinski
- Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Krakow, Poland
| | - K Gzielo
- Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Krakow, Poland
| | - Z Soltys
- Department of Neuroanatomy, Institute of Zoology, Jagiellonian University, Krakow, Poland
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56
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Proteolytic Remodeling of Perineuronal Nets: Effects on Synaptic Plasticity and Neuronal Population Dynamics. Neural Plast 2018. [PMID: 29531525 PMCID: PMC5817213 DOI: 10.1155/2018/5735789] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The perineuronal net (PNN) represents a lattice-like structure that is prominently expressed along the soma and proximal dendrites of parvalbumin- (PV-) positive interneurons in varied brain regions including the cortex and hippocampus. It is thus apposed to sites at which PV neurons receive synaptic input. Emerging evidence suggests that changes in PNN integrity may affect glutamatergic input to PV interneurons, a population that is critical for the expression of synchronous neuronal population discharges that occur with gamma oscillations and sharp-wave ripples. The present review is focused on the composition of PNNs, posttranslation modulation of PNN components by sulfation and proteolysis, PNN alterations in disease, and potential effects of PNN remodeling on neuronal plasticity at the single-cell and population level.
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57
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Härtig W, Mages B, Aleithe S, Nitzsche B, Altmann S, Barthel H, Krueger M, Michalski D. Damaged Neocortical Perineuronal Nets Due to Experimental Focal Cerebral Ischemia in Mice, Rats and Sheep. Front Integr Neurosci 2017; 11:15. [PMID: 28860977 PMCID: PMC5559442 DOI: 10.3389/fnint.2017.00015] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/10/2017] [Indexed: 01/08/2023] Open
Abstract
As part of the extracellular matrix (ECM), perineuronal nets (PNs) are polyanionic, chondroitin sulfate proteoglycan (CSPG)-rich coatings of certain neurons, known to be affected in various neural diseases. Although these structures are considered as important parts of the neurovascular unit (NVU), their role during evolution of acute ischemic stroke and subsequent tissue damage is poorly understood and only a few preclinical studies analyzed PNs after acute ischemic stroke. By employing three models of experimental focal cerebral ischemia, this study was focused on histopathological alterations of PNs and concomitant vascular, glial and neuronal changes according to the NVU concept. We analyzed brain tissues obtained 1 day after ischemia onset from: (a) mice after filament-based permanent middle cerebral artery occlusion (pMCAO); (b) rats subjected to thromboembolic MACO; and (c) sheep at 14 days after electrosurgically induced focal cerebral ischemia. Multiple fluorescence labeling was applied to explore simultaneous alterations of NVU and ECM. Serial mouse sections labeled with the net marker Wisteria floribunda agglutinin (WFA) displayed largely decomposed and nearly erased PNs in infarcted neocortical areas that were demarcated by up-regulated immunoreactivity for vascular collagen IV (Coll IV). Subsequent semi-quantitative analyses in mice confirmed significantly decreased WFA-staining along the ischemic border zone and a relative decrease in the directly ischemia-affected neocortex. Triple fluorescence labeling throughout the three animal models revealed up-regulated Coll IV and decomposed PNs accompanied by activated astroglia and altered immunoreactivity for parvalbumin, a calcium-binding protein in fast-firing GABAergic neurons which are predominantly surrounded by neocortical PNs. Furthermore, ischemic neocortical areas in rodents simultaneously displayed less intense staining of WFA, aggrecan, the net components neurocan, versican and the cartilage link protein (CRTL) as well as markers in net-bearing neurons such as the potassium channel subunit Kv3.1b and neuronal nuclei (NeuN). In summary, theconsistent observations based on three different stroke models confirmed that PNs are highly sensitive constituents of the NVU along with impaired associated GABAergic neurons. These results suggest that PNs could be promising targets of future stroke treatment, and further studies should address their reorganization and plasticity in both stabilizing the acute stroke as well as supportive effects during the chronic phase of stroke.
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Affiliation(s)
- Wolfgang Härtig
- Department of Pathophysiology of Neuroglia, Paul Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany
| | - Bianca Mages
- Department of Pathophysiology of Neuroglia, Paul Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany.,Department of Neurology, University of LeipzigLeipzig, Germany
| | - Susanne Aleithe
- Department of Pathophysiology of Neuroglia, Paul Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany.,Department of Neurology, University of LeipzigLeipzig, Germany
| | - Björn Nitzsche
- Department of Nuclear Medicine, University of LeipzigLeipzig, Germany.,Faculty of Veterinary Medicine, Institute of Anatomy, Histology and Embryology, University of LeipzigLeipzig, Germany
| | - Stephan Altmann
- Department of Pathophysiology of Neuroglia, Paul Flechsig Institute for Brain Research, University of LeipzigLeipzig, Germany.,Department of Neurology, University of LeipzigLeipzig, Germany
| | - Henryk Barthel
- Department of Nuclear Medicine, University of LeipzigLeipzig, Germany
| | - Martin Krueger
- Institute of Anatomy, University of LeipzigLeipzig, Germany
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58
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Kim SY, Senatorov VV, Morrissey CS, Lippmann K, Vazquez O, Milikovsky DZ, Gu F, Parada I, Prince DA, Becker AJ, Heinemann U, Friedman A, Kaufer D. TGFβ signaling is associated with changes in inflammatory gene expression and perineuronal net degradation around inhibitory neurons following various neurological insults. Sci Rep 2017; 7:7711. [PMID: 28794441 PMCID: PMC5550510 DOI: 10.1038/s41598-017-07394-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 06/27/2017] [Indexed: 01/17/2023] Open
Abstract
Brain damage due to stroke or traumatic brain injury (TBI), both leading causes of serious long-term disability, often leads to the development of epilepsy. Patients who develop post-injury epilepsy tend to have poor functional outcomes. Emerging evidence highlights a potential role for blood-brain barrier (BBB) dysfunction in the development of post-injury epilepsy. However, common mechanisms underlying the pathological hyperexcitability are largely unknown. Here, we show that comparative transcriptome analyses predict remodeling of extracellular matrix (ECM) as a common response to different types of injuries. ECM-related transcriptional changes were induced by the serum protein albumin via TGFβ signaling in primary astrocytes. In accordance with transcriptional responses, we found persistent degradation of protective ECM structures called perineuronal nets (PNNs) around fast-spiking inhibitory interneurons, in a rat model of TBI as well as in brains of human epileptic patients. Exposure of a naïve brain to albumin was sufficient to induce the transcriptional and translational upregulation of molecules related to ECM remodeling and the persistent breakdown of PNNs around fast-spiking inhibitory interneurons, which was contingent on TGFβ signaling activation. Our findings provide insights on how albumin extravasation that occurs upon BBB dysfunction in various brain injuries can predispose neural circuitry to the development of chronic inhibition deficits.
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Affiliation(s)
- Soo Young Kim
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, 94720, USA.
| | - Vladimir V Senatorov
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Christapher S Morrissey
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Kristina Lippmann
- Institute of Neurophysiology, Charité Universitätsmedizin Berlin, Berlin, D10117, Germany.,Carl-Ludwig-Institute for Physiology, Leipzig University, Leipzig, 04315, Germany
| | - Oscar Vazquez
- Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA
| | - Dan Z Milikovsky
- Departments of Cognitive and Brain Sciences, Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel
| | - Feng Gu
- Department of Neurology and Neurological Sciences, , Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Isabel Parada
- Department of Neurology and Neurological Sciences, , Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - David A Prince
- Department of Neurology and Neurological Sciences, , Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Albert J Becker
- Department of Neuropathology, University of Bonn Medical Center, Bonn, 53105, Germany
| | - Uwe Heinemann
- Institute of Neurophysiology, Charité Universitätsmedizin Berlin, Berlin, D10117, Germany
| | - Alon Friedman
- Departments of Cognitive and Brain Sciences, Physiology and Cell Biology, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, 84105, Israel.,Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada
| | - Daniela Kaufer
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA, 94720, USA. .,Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, 94720, USA. .,Canadian Institute for Advanced Research (CIFAR) Program in Child and Brain Development, ON M5G 1Z8, Toronto, Canada.
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59
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Miyata S, Kitagawa H. Formation and remodeling of the brain extracellular matrix in neural plasticity: Roles of chondroitin sulfate and hyaluronan. Biochim Biophys Acta Gen Subj 2017. [PMID: 28625420 DOI: 10.1016/j.bbagen.2017.06.010] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND The extracellular matrix (ECM) of the brain is rich in glycosaminoglycans such as chondroitin sulfate (CS) and hyaluronan. These glycosaminoglycans are organized into either diffuse or condensed ECM. Diffuse ECM is distributed throughout the brain and fills perisynaptic spaces, whereas condensed ECM selectively surrounds parvalbumin-expressing inhibitory neurons (PV cells) in mesh-like structures called perineuronal nets (PNNs). The brain ECM acts as a non-specific physical barrier that modulates neural plasticity and axon regeneration. SCOPE OF REVIEW Here, we review recent progress in understanding of the molecular basis of organization and remodeling of the brain ECM, and the involvement of several types of experience-dependent neural plasticity, with a particular focus on the mechanism that regulates PV cell function through specific interactions between CS chains and their binding partners. We also discuss how the barrier function of the brain ECM restricts dendritic spine dynamics and limits axon regeneration after injury. MAJOR CONCLUSIONS The brain ECM not only forms physical barriers that modulate neural plasticity and axon regeneration, but also forms molecular brakes that actively controls maturation of PV cells and synapse plasticity in which sulfation patterns of CS chains play a key role. Structural remodeling of the brain ECM modulates neural function during development and pathogenesis. GENERAL SIGNIFICANCE Genetic or enzymatic manipulation of the brain ECM may restore neural plasticity and enhance recovery from nerve injury. This article is part of a Special Issue entitled Neuro-glycoscience, edited by Kenji Kadomatsu and Hiroshi Kitagawa.
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Affiliation(s)
- Shinji Miyata
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Nagoya 464-8601, Japan
| | - Hiroshi Kitagawa
- Department of Biochemistry, Kobe Pharmaceutical University, 4-19-1 Motoyamakita-machi, Kobe 658-8558, Japan.
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60
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Ueno H, Suemitsu S, Okamoto M, Matsumoto Y, Ishihara T. Sensory experience-dependent formation of perineuronal nets and expression of Cat-315 immunoreactive components in the mouse somatosensory cortex. Neuroscience 2017; 355:161-174. [PMID: 28495333 DOI: 10.1016/j.neuroscience.2017.04.041] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 03/29/2017] [Accepted: 04/27/2017] [Indexed: 10/19/2022]
Abstract
Perineuronal nets (PNNs) are structures of extracellular matrix molecules surrounding the cell bodies and proximal dendrites of certain neurons. While PNNs are present throughout the mouse cerebral cortex, recent studies have shown that the components differ among cortical sub-regions and layers, suggesting region-specific functions. Parvalbumin-expressing interneurons (PV neurons) may be important regulators of cortical plasticity during the early "critical period" that is sensitive to sensory input. Here we examined the distribution and developmental functions of PNN components associated with PV neurons in the somatosensory cortex during the critical period. Aggrecan, brevican, neurocan, phosphacan, and tenascin-R were identified as PNN components in the mouse somatosensory cortex. High-magnification analysis revealed that some lectin Wisteria floribunda agglutinin (WFA)-reactive molecules did not co-localize with monoclonal antibody Cat-315 recognition molecules around the cell body. During postnatal development, Cat-315-positive (Cat-315+) PNNs appeared later than PNNs binding to the lectin WFA (WFA+ PNNs). These WFA+ PNNs changed from granular-like to reticular-like structures during normal cortical development, while this transition was delayed by sensory deprivation. This study indicates that the formation of reticular-like WFA+ PNNs is dependent on sensory experience in the mouse somatosensory cortex. We suggest that Cat-315+ molecules and WFA expression in PNNs are involved in the early critical period of input-dependent cortical plasticity.
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Affiliation(s)
- Hiroshi Ueno
- Department of Medical Technology, Kawasaki College of Allied Health Professions, Okayama 701-0194, Japan; Department of Medical Technology, Graduate School of Health Sciences, Okayama University, Okayama 700-8558, Japan.
| | - Shunsuke Suemitsu
- Department of Psychiatry, Kawasaki Medical School, Kurashiki 701-0192, Japan.
| | - Motoi Okamoto
- Department of Medical Technology, Graduate School of Health Sciences, Okayama University, Okayama 700-8558, Japan.
| | - Yosuke Matsumoto
- Department of Neuropsychiatry, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8558, Japan.
| | - Takeshi Ishihara
- Department of Psychiatry, Kawasaki Medical School, Kurashiki 701-0192, Japan.
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61
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Quattromani MJ, Pruvost M, Guerreiro C, Backlund F, Englund E, Aspberg A, Jaworski T, Hakon J, Ruscher K, Kaczmarek L, Vivien D, Wieloch T. Extracellular Matrix Modulation Is Driven by Experience-Dependent Plasticity During Stroke Recovery. Mol Neurobiol 2017; 55:2196-2213. [PMID: 28290150 PMCID: PMC5840227 DOI: 10.1007/s12035-017-0461-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Accepted: 02/16/2017] [Indexed: 11/24/2022]
Abstract
Following stroke, complete cellular death in the ischemic brain area may ensue, with remaining brain areas undergoing tissue remodelling to various degrees. Experience-dependent brain plasticity exerted through an enriched environment (EE) promotes remodelling after central nervous system injury, such as stroke. Post-stroke tissue reorganization is modulated by growth inhibitory molecules differentially expressed within the ischemic hemisphere, like chondroitin sulfate proteoglycans found in perineuronal nets (PNNs). PNNs in the neocortex predominantly enwrap parvalbumin-containing GABAergic (PV/GABA) neurons, important in sensori-information processing. Here, we investigate how extracellular matrix (ECM) proteases and their inhibitors may participate in the regulation of PNN integrity during stroke recovery. Rats were subjected to photothrombotic stroke in the motor cortex, and functional deficits were assessed at 7 days of recovery. Sham and stroked rats were housed in either standard or EE conditions for 5 days, and infarct volumes were calculated. PNNs were visualized by immunohistochemistry and counted in the somatosensory cortex of both hemispheres. mRNA expression levels of ECM proteases and protease inhibitors were assessed by RT-qPCR and their activity analyzed by gel zymography. PNNs and protease activity were also studied in brains from stroke patients where similar results were observed. EE starting 2 days after stroke and continuing for 5 days stimulated behavioral recovery of limb-placement ability without affecting infarct size. EE promoted a decrease of PNNs around PV/GABA neurons and a concomitant modulation of the proteolytic activity and mRNA expression of ECM proteases and protease inhibitors in the somatosensory cortex. This study provides molecular targets for novel therapies that could support rehabilitation of stroke patients.
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Affiliation(s)
- Miriana Jlenia Quattromani
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden.
| | - Mathilde Pruvost
- INSERM UMR-S U919, Serine Proteases and Pathophysiology of the Neurovascular Unit, Université Caen Basse Normandie, GIP Cyceron, F-14074, Caen, France
| | - Carla Guerreiro
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden
| | - Fredrik Backlund
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden
| | - Elisabet Englund
- Division of Oncology and Pathology, Lund University Hospital, 22185, Lund, Sweden
| | - Anders Aspberg
- Rheumatology and Molecular Skeletal Biology, Department of Clinical Sciences, Lund University, BMC C12, 22184, Lund, Sweden
| | - Tomasz Jaworski
- Laboratory of Neurobiology, Nencki Institute of Experimental Biology, 02-093, Warsaw, Poland
| | - Jakob Hakon
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden
| | - Karsten Ruscher
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden
| | - Leszek Kaczmarek
- Laboratory of Neurobiology, Nencki Institute of Experimental Biology, 02-093, Warsaw, Poland
| | - Denis Vivien
- INSERM UMR-S U919, Serine Proteases and Pathophysiology of the Neurovascular Unit, Université Caen Basse Normandie, GIP Cyceron, F-14074, Caen, France.,Department of Clinical Research, Caen University Hospital, CHU Caen, 14000, Caen, France
| | - Tadeusz Wieloch
- Laboratory for Experimental Brain Research, Division of Neurosurgery, Department of Clinical Sciences, Lund University, BMC A13, 22184, Lund, Sweden
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Khaspekov LG, Frumkina LE. Molecular mechanisms mediating involvement of glial cells in brain plastic remodeling in epilepsy. BIOCHEMISTRY (MOSCOW) 2017; 82:380-391. [DOI: 10.1134/s0006297917030178] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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63
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Dubey D, McRae PA, Rankin-Gee EK, Baranov E, Wandrey L, Rogers S, Porter BE. Increased metalloproteinase activity in the hippocampus following status epilepticus. Epilepsy Res 2017; 132:50-58. [PMID: 28292736 DOI: 10.1016/j.eplepsyres.2017.02.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Revised: 01/25/2017] [Accepted: 02/28/2017] [Indexed: 11/16/2022]
Abstract
Increased neuronal plasticity and neuronal cell loss has been implicated in the development of epilepsy following injury. Parvalbumin fast spiking inhibitory interneurons have a robust extracellular matrix coating their cell bodies and the proximal dendrites called the perineuronal net (PNN). The role of the PNN is not clear but it has been implicated in closing of the critical period, altering seizure thresholds and providing neuronal protection from oxidative stress. The PNN is susceptible to degradation following a prolonged seizure and there is an increase in proteolytic-fragments of the PNN enriched proteoglycan aggrecan (Dzwonek et al., 2004). Here we demonstrate an increase in matrix metalloproteinase (MMP) activity in the hippocampus following status epilepticus (SE). We further assessed MMP3 and 13, two of 24 identified MMPs, both MMP3 and 13 mRNA increase in the hippocampus after SE and MMP13 activity increases by functional assay as well as it co-localizes with PNN in rat brain. In contrast, two of the brain expressed ADAMTS (A Disintegrin And Metalloproteinase with ThromboSpondin motifs) also implicated in aggrecan degradation, did not consistently increase following SE though ADAMTS4 is highly expressed in glia and ADAMTS5 in neuronal cell bodies and their processes. The increase in MMP activity following SE suggests that in the future studies, MMP inhibitors are candidates for blocking PNN degradation and assessing the role of the PNN loss in epileptogenesis and cellular function.
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Affiliation(s)
- Deepti Dubey
- Department of Neurology, School of Medicine, Stanford University, 1201 Welch Road, P211 MSLS, Stanford CA 94305, United States
| | - Paulette A McRae
- The Children's Hospital of Philadelphia, Department of Pediatrics and Division of Neurology, 34th and Civic Center Boulevard, Philadelphia PA 19104, United States
| | - Elyse K Rankin-Gee
- Department of Neurology, School of Medicine, Stanford University, 1201 Welch Road, P211 MSLS, Stanford CA 94305, United States
| | - Esther Baranov
- The Children's Hospital of Philadelphia, Department of Pediatrics and Division of Neurology, 34th and Civic Center Boulevard, Philadelphia PA 19104, United States
| | - Luke Wandrey
- The Children's Hospital of Philadelphia, Department of Pediatrics and Division of Neurology, 34th and Civic Center Boulevard, Philadelphia PA 19104, United States
| | - Stephanie Rogers
- The Children's Hospital of Philadelphia, Department of Pediatrics and Division of Neurology, 34th and Civic Center Boulevard, Philadelphia PA 19104, United States
| | - Brenda E Porter
- Department of Neurology, School of Medicine, Stanford University, 1201 Welch Road, P211 MSLS, Stanford CA 94305, United States; The Children's Hospital of Philadelphia, Department of Pediatrics and Division of Neurology, 34th and Civic Center Boulevard, Philadelphia PA 19104, United States.
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64
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Su J, Cole J, Fox MA. Loss of Interneuron-Derived Collagen XIX Leads to a Reduction in Perineuronal Nets in the Mammalian Telencephalon. ASN Neuro 2017; 9:1759091416689020. [PMID: 28090790 PMCID: PMC5298462 DOI: 10.1177/1759091416689020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 11/22/2016] [Accepted: 12/14/2016] [Indexed: 01/09/2023] Open
Abstract
Perineuronal nets (PNNs) are lattice-like supramolecular assemblies of extracellular glycoproteins that surround subsets of neuronal cell bodies in the mammalian telencephalon. PNNs emerge at the end of the critical period of brain development, limit neuronal plasticity in the adult brain, and are lost in a variety of complex brain disorders diseases, including schizophrenia. The link between PNNs and schizophrenia led us to question whether neuronally expressed extracellular matrix (ECM) molecules associated with schizophrenia contribute to the assembly of these specialized supramolecular ECM assemblies. We focused on collagen XIX-a minor, nonfibrillar collagen expressed by subsets of telencephalic interneurons. Genetic alterations in the region encoding collagen XIX have been associated with familial schizophrenia, and loss of this collagen in mice results in altered inhibitory synapses, seizures, and the acquisition of schizophrenia-related behaviors. Here, we demonstrate that loss of collagen XIX also results in a reduction of telencephalic PNNs. Loss of PNNs was accompanied with reduced levels of aggrecan (Acan), a major component of PNNs. Despite reduced levels of PNN constituents in collagen XIX-deficient mice ( col19a1-/-), we failed to detect reduced expression of genes encoding these ECM molecules. Instead, we discovered a widespread upregulation of extracellular proteases capable of cleaving Acan and other PNN constituents in col19a1-/- brains. Taken together, these results suggest a mechanism by which the loss of collagen XIX speeds PNN degradation and they identify a novel mechanism by which the loss of collagen XIX may contribute to complex brain disorders.
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Affiliation(s)
- Jianmin Su
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA
| | - James Cole
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA
| | - Michael A. Fox
- Virginia Tech Carilion Research Institute, Roanoke, VA, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
- Department of Pediatrics, Virginia Tech Carilion School of Medicine, Roanoke, VA, USA
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65
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Härtig W, Appel S, Suttkus A, Grosche J, Michalski D. Abolished perineuronal nets and altered parvalbumin-immunoreactivity in the nucleus reticularis thalami of wildtype and 3xTg mice after experimental stroke. Neuroscience 2016; 337:66-87. [PMID: 27634771 DOI: 10.1016/j.neuroscience.2016.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/18/2016] [Accepted: 09/03/2016] [Indexed: 12/14/2022]
Abstract
Treatment strategies for ischemic stroke are still limited, since numerous attempts were successful only in preclinical research but failed under clinical condition. To overcome this translational roadblock, clinical relevant stroke models should consider co-morbidities, age-related effects and the complex neurovascular unit (NVU) concept. The NVU includes neurons, vessels and glial cells with astrocytic endfeet in close relation to the extracellular matrix (ECM). However, the role of the ECM after stroke-related tissue damage is poorly understood and mostly neglected for treatment strategies. This study is focused on alterations of perineuronal nets (PNs) as ECM constituents and parvalbumin-containing GABAergic neurons in mice with emphasis on the nucleus reticularis thalami (NRT) in close proximity to the ischemic lesion as induced by a filament-based stroke model. One day after ischemia onset, immunofluorescence-based quantitative analyses revealed drastically declined PNs in the ischemia-affected NRT from 3- and 12-month-old wildtype and co-morbid triple-transgenic (3xTg) mice with Alzheimer-like alterations. Parvalbumin-positive cells decreased numerically in the ischemia-affected NRT, while staining intensity did not differ between the affected and non-affected hemisphere. Additional qualitative analyses demonstrated ischemia-induced loss of PNs and allocated neuropil ECM immunoreactive for aggrecan and neurocan, and impaired immunoreactivity for calbindin, the potassium channel subunit Kv3.1b and the glutamate decarboxylase isoforms GAD65 and GAD67 in the NRT. In conclusion, these data confirm PNs as highly sensitive constituents of the ECM along with impaired neuronal integrity of GABAergic neurons. Therefore, specific targeting of ECM components might appear as a promising strategy for future treatment strategies in stroke.
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Affiliation(s)
- Wolfgang Härtig
- Paul Flechsig Institute for Brain Research University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany.
| | - Simon Appel
- Paul Flechsig Institute for Brain Research University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany
| | - Anne Suttkus
- Paul Flechsig Institute for Brain Research University of Leipzig, Liebigstr. 19, 04103 Leipzig, Germany; Department of Pediatric Surgery, University Hospital Leipzig, Liebigstr. 20 A, 04103 Leipzig, Germany
| | - Jens Grosche
- Effigos GmbH, Am Deutschen Platz 4, 04103 Leipzig, Germany
| | - Dominik Michalski
- Department of Neurology, University of Leipzig, Liebigstr. 20, 04103 Leipzig, Germany
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66
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Kim SY, Porter BE, Friedman A, Kaufer D. A potential role for glia-derived extracellular matrix remodeling in postinjury epilepsy. J Neurosci Res 2016; 94:794-803. [PMID: 27265805 DOI: 10.1002/jnr.23758] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 04/07/2016] [Accepted: 04/07/2016] [Indexed: 01/04/2023]
Abstract
Head trauma and vascular injuries are known risk factors for acquired epilepsy. The sequence of events that lead from the initial injury to the development of epilepsy involves complex plastic changes and circuit rewiring. In-depth, comprehensive understanding of the epileptogenic process is critical for the identification of disease-modifying targets. Here we review the complex interactions of cellular and extracellular components that may promote epileptogenesis, with an emphasis on the role of astrocytes. Emerging evidence demonstrates that astrocytes promptly respond to brain damage and play a critical role in the development of postinjury epilepsy. Astrocytes have been shown to regulate extracellular matrix (ECM) remodeling, which can affect plasticity and stability of synapses and, in turn, contribute to the epileptogenic process. From these separate lines of evidence, we present a hypothesis suggesting a possible role for astrocyte-regulated remodeling of ECM and perineuronal nets, a specialized ECM structure around fast-spiking inhibitory interneurons, in the development and progression of posttraumatic epilepsies. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Soo Young Kim
- Department of Integrative Biology, University of California, Berkeley, Berkeley, California.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California
| | - Brenda E Porter
- Department of Neurology, Stanford University School of Medicine, Palo Alto, California
| | - Alon Friedman
- Departments of Physiology and Cell Biology, Cognitive and Brain Sciences, Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Daniela Kaufer
- Department of Integrative Biology, University of California, Berkeley, Berkeley, California.,Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California.,Canadian Institute for Advanced Research Program in Child and Brain Development, Toronto, Ontario, Canada
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67
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In Sickness and in Health: Perineuronal Nets and Synaptic Plasticity in Psychiatric Disorders. Neural Plast 2015; 2016:9847696. [PMID: 26839720 PMCID: PMC4709762 DOI: 10.1155/2016/9847696] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/27/2015] [Indexed: 12/25/2022] Open
Abstract
Rapidly emerging evidence implicates perineuronal nets (PNNs) and extracellular matrix (ECM) molecules that compose or interact with PNNs, in the pathophysiology of several psychiatric disorders. Studies on schizophrenia, autism spectrum disorders, mood disorders, Alzheimer's disease, and epilepsy point to the involvement of ECM molecules such as chondroitin sulfate proteoglycans, Reelin, and matrix metalloproteases, as well as their cell surface receptors. In many of these disorders, PNN abnormalities have also been reported. In the context of the “quadripartite” synapse concept, that is, the functional unit composed of the pre- and postsynaptic terminals, glial processes, and ECM, and of the role that PNNs and ECM molecules play in regulating synaptic functions and plasticity, these findings resonate with one of the most well-replicated aspects of the pathology of psychiatric disorders, that is, synaptic abnormalities. Here we review the evidence for PNN/ECM-related pathology in these disorders, with particular emphasis on schizophrenia, and discuss the hypothesis that such pathology may significantly contribute to synaptic dysfunction.
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68
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Wiera G, Mozrzymas JW. Extracellular proteolysis in structural and functional plasticity of mossy fiber synapses in hippocampus. Front Cell Neurosci 2015; 9:427. [PMID: 26582976 PMCID: PMC4631828 DOI: 10.3389/fncel.2015.00427] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 10/09/2015] [Indexed: 02/04/2023] Open
Abstract
Brain is continuously altered in response to experience and environmental changes. One of the underlying mechanisms is synaptic plasticity, which is manifested by modification of synapse structure and function. It is becoming clear that regulated extracellular proteolysis plays a pivotal role in the structural and functional remodeling of synapses during brain development, learning and memory formation. Clearly, plasticity mechanisms may substantially differ between projections. Mossy fiber synapses onto CA3 pyramidal cells display several unique functional features, including pronounced short-term facilitation, a presynaptically expressed long-term potentiation (LTP) that is independent of NMDAR activation, and NMDA-dependent metaplasticity. Moreover, structural plasticity at mossy fiber synapses ranges from the reorganization of projection topology after hippocampus-dependent learning, through intrinsically different dynamic properties of synaptic boutons to pre- and postsynaptic structural changes accompanying LTP induction. Although concomitant functional and structural plasticity in this pathway strongly suggests a role of extracellular proteolysis, its impact only starts to be investigated in this projection. In the present report, we review the role of extracellular proteolysis in various aspects of synaptic plasticity in hippocampal mossy fiber synapses. A growing body of evidence demonstrates that among perisynaptic proteases, tissue plasminogen activator (tPA)/plasmin system, β-site amyloid precursor protein-cleaving enzyme 1 (BACE1) and metalloproteinases play a crucial role in shaping plastic changes in this projection. We discuss recent advances and emerging hypotheses on the roles of proteases in mechanisms underlying mossy fiber target specific synaptic plasticity and memory formation.
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Affiliation(s)
- Grzegorz Wiera
- Department of Animal Molecular Physiology, Institute of Experimental Biology, Wroclaw University Wroclaw, Poland ; Laboratory of Neuroscience, Department of Biophysics, Wroclaw Medical University Wroclaw, Poland
| | - Jerzy W Mozrzymas
- Department of Animal Molecular Physiology, Institute of Experimental Biology, Wroclaw University Wroclaw, Poland ; Laboratory of Neuroscience, Department of Biophysics, Wroclaw Medical University Wroclaw, Poland
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