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Protective Functions of PJ34, a Poly(ADP-ribose) Polymerase Inhibitor, Are Related to Down-Regulation of Calpain and Nuclear Factor-κB in a Mouse Model of Traumatic Brain Injury. World Neurosurg 2017. [PMID: 28642177 DOI: 10.1016/j.wneu.2017.06.076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECTIVES Poly(ADP-ribose) polymerase (PARP), calpain, and nuclear factor-κB (NF-κB) are reported to participate in inflammatory reactions in pathologic conditions and are involved in traumatic brain injury. The objective of this study was to investigate whether PARP participates in inflammation related to calpain and NF-κB in a mouse model of controlled cortical impact (CCI). METHODS PJ34 (10 mg/kg), a selective PARP inhibitor, was administered intraperitoneally 5 minutes and 8 hours after experimental CCI. We then performed a histopathologic analysis, and we measured calpain activity and protein levels in all animals. The cytosolic, mitochondria, and nuclear fractions were prepared and used to determine the levels of PARP, calpastatin, NF-κB p65, inhibitory-κB-α, tumor necrosis factor-α, interleukin-1β, intracellular adhesion molecule-1, inducible nitric oxide synthase, and cyclooxygenase-2. We then measured blood-brain barrier disruption using electron microscopy at 6 and 24 hours after CCI. RESULTS Treatment with PJ34 markedly reduced the extent of both cerebral contusion and edema, improved neurologic scores, and attenuated blood-brain barrier damage resulting from CCI. Our data showed that the cytosolic and nuclear fractions of calpain and NF-κB were up-regulated in the injured cortex and that these changes were reversed by PJ34. Moreover, PJ34 significantly enhanced the calpastatin and inhibitory-κB levels and decreased the levels of inflammatory mediators. CONCLUSIONS PARP inhibition by PJ34 suppresses the overactivation of calpain and the production of inflammatory factors that are caused by NF-κB activation and attenuates neuronal cell death in a mouse model of CCI.
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Tao X, Chen X, Mao X, Hou Z, Hao S, Tian R, Zhu Z, Sun M, Liu B. Protective effects of PARP inhibitor, PJ34, is related to down-regulation of calpain and NF-κB in a mouse model of TBI. Brain Inj 2016:1-11. [PMID: 27119554 DOI: 10.3109/02699052.2016.1160151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Poly(ADP-ribose) polymerase (PARP), calpain and nuclear factor-κB (NF-κB) are reported to participate in inflammatory reactions in pathological conditions and are involved in traumatic brain injury. The objective of this study was to investigate whether PARP participated in inflammation related to calpain and NF-κB in a mouse model of controlled cortical impact (CCI). MATERIALS AND METHODS PJ34 (10 mg kg-1), a selective PARP inhibitor, was administered intraperitoneally 5 minutes and 8 hours after experimental CCI. A neurobehavioural evaluation and a histopathological analysis were then performed and the contusion volume, calpain activity and protein levels were measured in all animals. RESULTS Treatment with PJ34 markedly reduced neurological deficits, decreased contusion volume and attenuated necrotic and apoptotic neuronal cell death 24 hours after CCI. The data showed that the cytosolic and nuclear fractions of calpain and NF-κB were up-regulated in the injured cortex and that these changes were reversed by PJ34. Moreover, PJ34 significantly enhanced the calpastatin and IκB levels and decreased the levels of inflammatory mediators. CONCLUSIONS PARP inhibition by PJ34 suppresses the over-activation of calpain and the production of inflammatory factors that are caused by NF-κB activation and it improves neurological functioning, decreases the contusion volume and attenuates neuronal cell death in a mouse model of CCI.
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Affiliation(s)
- Xiaogang Tao
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Xuetao Chen
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Xiang Mao
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Zonggang Hou
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Shuyu Hao
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Runfa Tian
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
| | - Zhendan Zhu
- b Department of Neurotrauma, General Hospital of the Armed Police Force , Beijing , PR China
| | - Ming Sun
- c Department of Neuropharmacology
| | - Baiyun Liu
- a Department of Neurosurgery, Beijing Tiantan Hospital , Capital Medical University , Beijing , PR China
- b Department of Neurotrauma, General Hospital of the Armed Police Force , Beijing , PR China
- d Department of Neurotrauma , Beijing Neurosurgical Institute, Capital Medical University , Beijing , PR China
- e Nerve Injury and Repair Center of Beijing Institute for Brain Disorders , Beijing , PR China
- f China National Clinical Research Center for Neurological Diseases , Beijing , PR China
- g Beijing Key Laboratory of Central Nervous System Injury , Beijing , PR China
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Logsdon AF, Lucke-Wold BP, Turner RC, Huber JD, Rosen CL, Simpkins JW. Role of Microvascular Disruption in Brain Damage from Traumatic Brain Injury. Compr Physiol 2015; 5:1147-60. [PMID: 26140712 PMCID: PMC4573402 DOI: 10.1002/cphy.c140057] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Traumatic brain injury (TBI) is acquired from an external force, which can inflict devastating effects to the brain vasculature and neighboring neuronal cells. Disruption of vasculature is a primary effect that can lead to a host of secondary injury cascades. The primary effects of TBI are rapidly occurring while secondary effects can be activated at later time points and may be more amenable to targeting. Primary effects of TBI include diffuse axonal shearing, changes in blood-brain barrier (BBB) permeability, and brain contusions. These mechanical events, especially changes to the BBB, can induce calcium perturbations within brain cells producing secondary effects, which include cellular stress, inflammation, and apoptosis. These secondary effects can be potentially targeted to preserve the tissue surviving the initial impact of TBI. In the past, TBI research had focused on neurons without any regard for glial cells and the cerebrovasculature. Now a greater emphasis is being placed on the vasculature and the neurovascular unit following TBI. A paradigm shift in the importance of the vascular response to injury has opened new avenues of drug-treatment strategies for TBI. However, a connection between the vascular response to TBI and the development of chronic disease has yet to be elucidated. Long-term cognitive deficits are common amongst those sustaining severe or multiple mild TBIs. Understanding the mechanisms of cellular responses following TBI is important to prevent the development of neuropsychiatric symptoms. With appropriate intervention following TBI, the vascular network can perhaps be maintained and the cellular repair process possibly improved to aid in the recovery of cellular homeostasis.
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Affiliation(s)
- Aric F Logsdon
- Department of Pharmaceutical Sciences, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Brandon P Lucke-Wold
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Ryan C Turner
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Jason D Huber
- Department of Pharmaceutical Sciences, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - Charles L Rosen
- Department of Neurosurgery, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
| | - James W Simpkins
- Department of Physiology and Pharmacology, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
- Center for Neuroscience, West Virginia University, Health Sciences Center, Morgantown, West Virginia, USA
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Koo HM, Lee SM, Kim MH. Spontaneous Wheel Running Exercise Induces Brain Recovery via Neurotrophin-3 Expression Following Experimental Traumatic Brain Injury in Rats. J Phys Ther Sci 2013; 25:1103-7. [PMID: 24259924 PMCID: PMC3818758 DOI: 10.1589/jpts.25.1103] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 04/19/2013] [Indexed: 11/24/2022] Open
Abstract
[Purpose] The aim of the present study was to investigate the expression of
neurotrophin-3 (NT-3) after applying spontaneous wheel running exercises (SWR) after
experimental traumatic brain injury (TBI). [Subjects and Methods] Thirty male
Sprague-Dawley rats were divided into 3 groups; 20 rats were subjected to controlled
cortical impact for TBI, and then, animals were randomly collected from the SWR group and
subjected to wheel running exercise for 3 weeks. Ten rats were not subjected to any injury
or running exercise to compare with the effect of TBI and SWR. Immunohistochemistry,
Western blotting, skilled ladder rung walking test, and 2,3,5-triphenyltetrazolium
chloride staining analysis for the evaluation of NT-3 expression were used to assess brain
damage and recovery. [Results] The TBI-induced decrease in NT-3 expression was recovered
by wheel running exercise. Moreover, decreased ischemic volume and progressive
neurobehavioral outcome were observed in the SWR group. [Conclusion] Spontaneous running
exercise promotes brain recovery and motor function through an increase in expression of
NT-3.
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Affiliation(s)
- Hyun Mo Koo
- Department of Physical Therapy, College of Science, Kyungsung University
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Schoch KM, Evans HN, Brelsfoard JM, Madathil SK, Takano J, Saido TC, Saatman KE. Calpastatin overexpression limits calpain-mediated proteolysis and behavioral deficits following traumatic brain injury. Exp Neurol 2012; 236:371-82. [PMID: 22572592 DOI: 10.1016/j.expneurol.2012.04.022] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 03/23/2012] [Accepted: 04/23/2012] [Indexed: 02/06/2023]
Abstract
Traumatic brain injury (TBI) results in abrupt, initial cell damage leading to delayed neuronal death. The calcium-activated proteases, calpains, are known to contribute to this secondary neurodegenerative cascade. Although the specific inhibitor of calpains, calpastatin, is present within neurons, normal levels of calpastatin are unable to fully prevent the damaging proteolytic activity of calpains after injury. In this study, increased calpastatin expression was achieved using transgenic mice that overexpress the human calpastatin (hCAST) construct under control of a calcium-calmodulin-dependent kinase II α promoter. Naïve hCAST transgenic mice exhibited enhanced neuronal calpastatin expression and significantly reduced protease activity. Acute calpain-mediated spectrin proteolysis in the cortex and hippocampus induced by controlled cortical impact brain injury was significantly attenuated in calpastatin overexpressing mice. Aspects of posttraumatic motor and cognitive behavioral deficits were also lessened in hCAST transgenic mice compared to their wildtype littermates. However, volumetric analyses of neocortical contusion revealed no histological neuroprotection at either acute or long-term time points. Partial hippocampal neuroprotection observed at a moderate injury severity was lost after severe TBI. This study underscores the effectiveness of calpastatin overexpression in reducing calpain-mediated proteolysis and behavioral impairment after TBI, supporting the therapeutic potential for calpain inhibition. In addition, the reduction in spectrin proteolysis without accompanied neocortical neuroprotection suggests the involvement of other factors that are critical for neuronal survival after contusion brain injury.
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Affiliation(s)
- Kathleen M Schoch
- Spinal Cord and Brain Injury Research Center, University of Kentucky, B416 Biomedical and Biological Sciences Research Building, 741 South Limestone Street, Lexington, KY 40536-0509, USA.
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Saatman KE, Creed J, Raghupathi R. Calpain as a therapeutic target in traumatic brain injury. Neurotherapeutics 2010; 7:31-42. [PMID: 20129495 PMCID: PMC2842949 DOI: 10.1016/j.nurt.2009.11.002] [Citation(s) in RCA: 161] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 11/16/2009] [Accepted: 11/16/2009] [Indexed: 02/01/2023] Open
Abstract
The family of calcium-activated neutral proteases, calpains, appears to play a key role in neuropathologic events following traumatic brain injury (TBI). Neuronal calpain activation has been observed within minutes to hours after either contusive or diffuse brain trauma in animals, suggesting that calpains are an early mediator of neuronal damage. Whereas transient calpain activation triggers numerous cell signaling and remodeling events involved in normal physiological processes, the sustained calpain activation produced by trauma is associated with neuron death and axonal degeneration in multiple models of TBI. Nonetheless, the causal relationship between calpain activation and neuronal death is not fully understood. Much remains to be learned regarding the endogenous regulatory mechanisms for controlling calpain activity, the roles of different calpain isoforms, and the in vivo substrates affected by calpain. Detection of stable proteolytic fragments of the submembrane cytoskeletal protein alphaII-spectrin specific for cleavage by calpains has been the most widely used marker of calpain activation in models of TBI. More recently, these protein fragments have been detected in the cerebrospinal fluid after TBI, driving interest in their potential utility as TBI-associated biomarkers. Post-traumatic inhibition of calpains, either direct or indirect through targets related to intracellular calcium regulation, is associated with attenuation of functional and behavioral deficits, axonal pathology, and cell death in animal models of TBI. This review focuses on the current state of knowledge of the role of calpains in TBI-induced neuropathology and effectiveness of calpain as a therapeutic target in the acute post-traumatic period.
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Affiliation(s)
- Kathryn E Saatman
- Spinal Cord and Brain Injury Research Center, Department of Physiology, University of Kentucky, Lexington, Kentucky 40536-0509, USA.
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Marmarou CR, Povlishock JT. Administration of the immunophilin ligand FK506 differentially attenuates neurofilament compaction and impaired axonal transport in injured axons following diffuse traumatic brain injury. Exp Neurol 2006; 197:353-62. [PMID: 16297913 DOI: 10.1016/j.expneurol.2005.10.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2005] [Revised: 09/23/2005] [Accepted: 10/11/2005] [Indexed: 10/25/2022]
Abstract
Traumatic axonal injury (TAI) following traumatic brain injury (TBI) remains a clinical problem for which no effective treatment exists. TAI was thought to involve intraaxonal changes that universally led to impaired axonal transport (IAT), disconnection and axonal bulb formation. However, recent, immunocytochemical studies employing antibodies to amyloid precursor protein (APP), a marker of IAT and antibodies to neurofilament compaction (NFC), RM014, demonstrated that NFC typically occurs independent of IAT, indicating the existence of different populations of damaged axons. FK506 administration has been shown to attenuate IAT. However, in light of the above, the ability of FK506 to attenuate axonal damage demonstrating NFC requires evaluation. The current study explored the potential of FK506 to attenuate both populations of damaged axons. Rats were administered FK506 (3 mg/kg) or vehicle 30 min preinjury. Three hours post-TBI, tissue was prepared for the visualization of TAI using antibodies targeting IAT (APP) or NFC (RMO14) or a combined labeling strategy. Confirming previous reports, FK506 treatment reduced the number of axons demonstrating IAT in the CSpT, from 411 +/- 54.70 to 91.00 +/- 33.87 (P <or= 0.05) and in the ML from 78.62 +/- 16.87 to 41.00 +/- 5.80 (P <or= 0.05). FK506 treatment failed to reduce the number of axons demonstrating NFC in either the CSpT or ML. FK506's failure to attenuate NFC suggests that additional therapeutic agents may be necessary to blunt the full burden of TAI. Because FK506 targets IAT, calcineurin appears to be a major target for neuroprotection in damaged axons demonstrating IAT.
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Affiliation(s)
- Christina R Marmarou
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, PO Box 980709, Richmond, 23298, USA
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FLOYD CANDACEL, GORIN FREDRICA, LYETH BRUCEG. Mechanical strain injury increases intracellular sodium and reverses Na+/Ca2+ exchange in cortical astrocytes. Glia 2005; 51:35-46. [PMID: 15779085 PMCID: PMC2996279 DOI: 10.1002/glia.20183] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Traditionally, astrocytes have been considered less susceptible to injury than neurons. Yet, we have recently shown that astrocyte death precedes neuronal death in a rat model of traumatic brain injury (TBI) (Zhao et al.: Glia 44:140-152, 2003). A main mechanism hypothesized to contribute to cellular injury and death after TBI is elevated intracellular calcium ([Ca2+]i). Since calcium regulation is also influenced by regulation of intracellular sodium ([Na+]i), we used an in vitro model of strain-induced traumatic injury and live-cell fluorescent digital imaging to investigate alterations in [Na+]i in cortical astrocytes after injury. Changes in [Na+]i, or [Ca2+]i were monitored after mechanical injury or L-glutamate exposure by ratiometric imaging of sodium-binding benzofuran isophthalate (SBFI-AM), or Fura-2-AM, respectively. Mechanical strain injury or exogenous glutamate application produced increases in [Na+]i that were dependent on the severity of injury or concentration. Injury-induced increases in [Na+]i were significantly reduced, but not completely eliminated, by inhibition of glutamate uptake by DL-threo-beta-benzyloxyaspartate (TBOA). Blockade of sodium-dependent calcium influx through the sodium-calcium exchanger with 2-[2-[4-(4-Nitrobenzyloxy)phenyl]ethyl]isothiourea mesylate (KB-R7943) reduced [Ca2+]i after injury. KB-R7943 also reduced astrocyte death after injury. These findings suggest that in astrocytes subjected to mechanical injury or glutamate excitotoxicity, increases in intracellular Na+ may be a critical component in the injury cascade and a therapeutic target for reduction of lasting deficits after traumatic brain injury.
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Affiliation(s)
- CANDACE L. FLOYD
- Department of Neurological Surgery, Center for Neuroscience, University of California, Davis, California
| | - FREDRIC A. GORIN
- Department of Neurology, Center for Neuroscience, University of California, Davis, California
| | - BRUCE G. LYETH
- Department of Neurological Surgery, Center for Neuroscience, University of California, Davis, California
- Correspondence to: Bruce G. Lyeth, Department of Neurological Surgery, University of California at Davis, 1515 Newton Court, One Shields Avenue, Davis, CA 95616-8797.
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Wingrave JM, Sribnick EA, Wilford GG, Matzelle DD, Mou JA, Ray SK, Hogan EL, Banik NL. Higher calpastatin levels correlate with resistance to calpain-mediated proteolysis and neuronal apoptosis in juvenile rats after spinal cord injury. J Neurotrauma 2004; 21:1240-54. [PMID: 15453993 DOI: 10.1089/neu.2004.21.1240] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
While the average age for patients admitted with spinal cord injury is 32 years, patients under the age of 16 account for 5% of spinal cord injured persons. For these younger patients, an increased mortality up to 24 h post-injury has been reported, however, survivors may regain more function than their adult counterparts, suggesting that age may play a role in injury tolerance. While the use of growth factors as a therapy for spinal cord injury is well researched, the response of the developing cord to secondary injury has not been thoroughly investigated. Following spinal cord injury, Ca(2+) influx can activate enzymes such as calpain, a Ca(2+)-dependent protease, which plays a role in the pathogenesis of spinal cord injury in rats. The present investigation revealed that following spinal cord injury, calpain upregulation was significantly less (15.3%) in the 21-day-old rats than in either 45-day-old (70%) or 90-day-old (99.6%) rats, as shown by Western blot and in situ immunofluorescent studies. Expression of the endogenous calpain inhibitor, calpastatin, was significantly higher in juvenile rats than adult rats. Juvenile rats with spinal cord injury also showed a reduced Bax:Bcl-2 ratio (4:1 vs. 6:1), reduced caspase-3 staining, reduced myelin loss (3% vs. 18%), and less neuronal DNA damage, as compared to older rats. These results suggest that increased calpastatin levels found in juvenile rats muted calpain activity and neuronal apoptosis, following spinal cord injury.
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Affiliation(s)
- James Michael Wingrave
- Department of Pathology, Medical University of South Carolina, Charleston, SC 29425, USA
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Ringger NC, Tolentino PJ, McKinsey DM, Pike BR, Wang KKW, Hayes RL. Effects of Injury Severity on Regional and Temporal mRNA Expression Levels of Calpains and Caspases after Traumatic Brain Injury in Rats. J Neurotrauma 2004; 21:829-41. [PMID: 15307896 DOI: 10.1089/0897715041526177] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Despite a preponderance of studies demonstrating gene expression and/or enzymatic activation of calpain and caspase proteases after traumatic brain injury (TBI), no studies have examined the effects of injury magnitude on expression levels of these cell death effectors after TBI. Determination of the degree to which injury severity affects specific expression profiles is critical to understanding the relevant pathways contributing to post-trauma pathology and for developing targeted therapeutics. This investigation tested the hypothesis that different injury magnitudes (1.0, 1.2, and 1.6 mm) cause alterations in the regional and temporal patterns of mRNA expression of calpain-related (calpain-1 and -2, calpastatin) and caspase-related (caspases -3, -8, -9, BID) gene products after cortical impact in rats. Quantitative RT-PCR was used to compare effects of injury severity on mRNA levels in ipsilateral (injured) cortex and hippocampus, 6 h to 5 days post-injury. TBI caused increases in mRNA expression of all proteins examined, with the highest expression detected in the cortex. Generally, injury magnitude and levels of gene expression were positively correlated. High levels of gene induction were observed with BID, caspase-3, and -8, while caspase-9 mRNA had the lowest level of induction. Interestingly, although calpains are activated within minutes of TBI, calpain mRNA expression was highest 72 h to 5 days post-TBI. This study is the first analysis of the regional and temporal expression of calpains and caspases after TBI. These data provide insight into the inter-relationship of these two protease families and on the distinct but overlapping cascades of cell death after TBI.
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Affiliation(s)
- N C Ringger
- Department of Neuroscience, Evelyn F. and William L. McKnight Brain Institute of the University of Florida, Gainesville, Florida, USA.
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