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Chohan MO, Flores RA, Wertz C, Jung RE. "Non-Eloquent" brain regions predict neuropsychological outcome in tumor patients undergoing awake craniotomy. PLoS One 2024; 19:e0284261. [PMID: 38300915 PMCID: PMC10833519 DOI: 10.1371/journal.pone.0284261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 03/28/2023] [Indexed: 02/03/2024] Open
Abstract
Supratotal resection of primary brain tumors is being advocated especially when involving "non-eloquent" tissue. However, there is extensive neuropsychological data implicating functions critical to higher cognition in areas considered "non-eloquent" by most surgeons. The goal of the study was to determine pre-surgical brain regions that would be predictive of cognitive outcome at 4-6 months post-surgery. Cortical reconstruction and volumetric segmentation were performed with the FreeSurfer-v6.0 image analysis suite. Linear regression models were used to regress cortical volumes from both hemispheres, against the total cognitive z-score to determine the relationship between brain structure and broad cognitive functioning while controlling for age, sex, and total segmented brain volume. We identified 62 consecutive patients who underwent planned awake resections of primary (n = 55, 88%) and metastatic at the University of New Mexico Hospital between 2015 and 2019. Of those, 42 (23 males, 25 left hemispheric lesions) had complete pre and post-op neuropsychological data available and were included in this study. Overall, total neuropsychological functioning was somewhat worse (p = 0.09) at post-operative neuropsychological outcome (Mean = -.20) than at baseline (Mean = .00). Patients with radiation following resection (n = 32) performed marginally worse (p = .036). We found that several discrete brain volumes obtained pre-surgery predicted neuropsychological outcome post-resection. For the total sample, these volumes included: left fusiform, right lateral orbital frontal, right post central, and right paracentral regions. Regardless of lesion lateralization, volumes within the right frontal lobe, and specifically right orbitofrontal cortex, predicted neuropsychological difference scores. The current study highlights the gaps in our current understanding of brain eloquence. We hypothesize that the volume of tissue within the right lateral orbital frontal lobe represents important cognitive reserve capacity in patients undergoing tumor surgery. Our data also cautions the neurosurgeon when considering supratotal resections of tumors that do not extend into areas considered "non-eloquent" by current standards.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, Mississippi, United States of America
| | - Ranee Ann Flores
- Department of Neurosurgery, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States of America
| | - Christopher Wertz
- Department of Neurosurgery, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States of America
| | - Rex Eugene Jung
- Department of Neurosurgery, University of New Mexico Health Sciences Center, Albuquerque, New Mexico, United States of America
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Wang W, Kumm ZT, Ho C, Zanesco-Fontes I, Texiera G, Reis RM, Martinetto H, Khan J, McCandless MG, Baker KE, Anderson MD, Chohan MO, Beyer S, Elder JB, Giglio P, Otero JJ. Unsupervised machine learning models reveal predictive clinical markers of glioblastoma patient survival using white blood cell counts prior to initiating chemoradiation. Neurooncol Adv 2024; 6:vdad140. [PMID: 38405202 PMCID: PMC10894654 DOI: 10.1093/noajnl/vdad140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2024] Open
Abstract
Background Glioblastoma is a malignant brain tumor requiring careful clinical monitoring even after primary management. Personalized medicine has suggested the use of various molecular biomarkers as predictors of patient prognosis or factors utilized for clinical decision-making. However, the accessibility of such molecular testing poses a constraint for various institutes requiring identification of low-cost predictive biomarkers to ensure equitable care. Methods We collected retrospective data from patients seen at Ohio State University, University of Mississippi, Barretos Cancer Hospital (Brazil), and FLENI (Argentina) who were managed for glioblastoma-amounting to 581 patient records documented using REDCap. Patients were evaluated using an unsupervised machine learning approach comprised of dimensionality reduction and eigenvector analysis to visualize the inter-relationship of collected clinical features. Results We discovered that the serum white blood cell (WBC) count of a patient during baseline planning for treatment was predictive of overall survival with an over 6-month median survival difference between the upper and lower quartiles of WBC count. By utilizing an objective PD-L1 immunohistochemistry quantification algorithm, we were further able to identify an increase in PD-L1 expression in glioblastoma patients with high serum WBC counts. Conclusions These findings suggest that in a subset of glioblastoma patients the incorporation of WBC count and PD-L1 expression in the brain tumor biopsy as simple biomarkers predicting glioblastoma patient survival. Moreover, machine learning models allow the distillation of complex clinical data sets to uncover novel and meaningful clinical relationships.
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Affiliation(s)
- Wesley Wang
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Zeynep Temerit Kumm
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Cindy Ho
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | | | - Gustavo Texiera
- Department of Pathology, Barretos Cancer Hospital, Barretos, Brazil
| | - Rui Manuel Reis
- Molecular Oncology Research Center, Barretos Cancer Hospital, Barretos, Brazil
- Life and Health Sciences Research Institute (ICVS)/School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Braga-Guimarães, Portugal
| | - Horacio Martinetto
- Departamento de Neuropatología y Biología Molecular, Instituto de Investigaciones Neurológicas Dr Raúl Carrea (FLENI), Buenos Aires, Argentina
| | - Javaria Khan
- Department of Pathology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Martin G McCandless
- Department of Neuro-Oncology, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Katherine E Baker
- Department of Neuro-Oncology, University of Mississippi Medical Center, Jackson, Mississippi, USA
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Mark D Anderson
- Department of Neuro-Oncology, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Muhammad Omar Chohan
- Department of Neurosurgery, University of Mississippi Medical Center, Jackson, Mississippi, USA
| | - Sasha Beyer
- Department of Radiation Oncology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - J Brad Elder
- Department of Neurosurgery, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Pierre Giglio
- Department of Neurology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - José Javier Otero
- Department of Pathology, Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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Kazim SF, Martinez E, Hough TJ, Spangler BQ, Bowers CA, Chohan MO. The Survival Benefit of Postoperative Bacterial Infections in Patients With Glioblastoma Multiforme: Myth or Reality? Front Neurol 2021; 12:615593. [PMID: 33613432 PMCID: PMC7894197 DOI: 10.3389/fneur.2021.615593] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 01/14/2021] [Indexed: 01/05/2023] Open
Abstract
Glioblastoma multiforme (GBM), the most common malignant brain tumor, universally carries a poor prognosis. Despite aggressive multimodality treatment, the median survival is ~18-20 months, depending on molecular subgroups. A long history of observations suggests antitumor effects of bacterial infections against malignant tumors. The present review summarizes and critically analyzes the clinical data providing evidence for or against the survival benefit of post-operative bacterial infections in GBM patients. Furthermore, we explore the probable underlying mechanism(s) from basic science studies on the topic. There are plausible explanations from immunobiology for the mechanism of the "favorable effect" of bacterial infections in GBM patients. However, available clinical literature does not provide a definitive association between postoperative bacterial infection and prolonged survival in GBM patients. The presently available, single-/multi-center and national database retrospective case-control studies on the topic provide conflicting results. A prospective randomized study on the subject is clearly not possible. Immunobiology literature supports development of genetically modified bacteria as part of multimodal regimen against GBM.
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Affiliation(s)
- Syed Faraz Kazim
- Department of Neurosurgery, University of New Mexico Hospital (UNMH), Albuquerque, NM, United States
| | - Erick Martinez
- School of Medicine, New York Medical College (NYMC), Valhalla, NY, United States
| | - Tyler J Hough
- School of Medicine, University of New Mexico (UNM), Albuquerque, NM, United States
| | - Benjamin Q Spangler
- School of Medicine, University of New Mexico (UNM), Albuquerque, NM, United States
| | - Christian A Bowers
- Department of Neurosurgery, University of New Mexico Hospital (UNMH), Albuquerque, NM, United States
| | - Muhammad Omar Chohan
- Department of Neurosurgery, University of Mississippi Medical Center (UMMC), Jackson, MS, United States
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Voronovich ZA, Vakamudi K, Posse S, Jung R, Chohan MO. Segmental reorganization of the leg primary motor area. Interdisciplinary Neurosurgery 2020. [DOI: 10.1016/j.inat.2020.100763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Mohammad LM, Botros JA, Chohan MO. Necessity of brain imaging in COVID-19 infected patients presenting with acute neurological deficits. Interdiscip Neurosurg 2020; 22:100883. [PMID: 32835024 PMCID: PMC7423580 DOI: 10.1016/j.inat.2020.100883] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/14/2020] [Accepted: 08/09/2020] [Indexed: 01/02/2023]
Abstract
Overlap with respiratory and neurological symptoms in the COVID-19 population. Obtain early head imaging in COVID-19 patients with a poor neurological exam. COVID-19 patients can develop CVAs and may benefit from neurosurgical interventions.
Background Patients undergoing cardiopulmonary stabilization in the intensive care unit for novel coronavirus (COVID-19) are often sedated, placing timely assessment of a neurological decline at risk. Case description Here, we present two cases of COVID-19 infected young patients transferred to our facility in a cardio-pulmonary crisis, with a poor neurological exam. While there was significant delay in obtaining brain imaging in the first patient, the second patient had timely recognition of her ischemic infarct, underwent emergent surgery, and is now doing well. Conclusions These cases highlight the importance of early head imaging in COVID-19 patients with a poor neurological exam. While lungs remain the primary target of COVID-19, these cases alert the medical community to suspect involvement of the central nervous system, since there may be life-saving surgical interventions available.
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Affiliation(s)
- Laila Malani Mohammad
- Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | - James A Botros
- Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, United States
| | - Muhammad Omar Chohan
- Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, United States
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Chohan MO, Kahn S, Cederquist G, Reiner AS, Schwab J, Laufer I, Bilsky M. Surgical Decompression of High-Grade Spinal Cord Compression from Hormone Refractory Metastatic Prostate Cancer. Neurosurgery 2019; 82:670-677. [PMID: 28541420 DOI: 10.1093/neuros/nyx292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 05/01/2017] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Spine and nonspine skeletal metastases occur in more than 80% of patients with prostate cancer. OBJECTIVE To examine the characteristics of the patient population undergoing surgery for the treatment of prostate cancer metastatic to the spine. METHODS A retrospective chart review was performed on all patients treated at our institution from June 1993 to August 2014 for surgical management of metastatic spine disease from prostate cancer. RESULTS During the study period, 139 patients with 157 surgical lesions underwent surgery for metastatic spine disease. Decompression for high-grade epidural spinal cord compression was required for 126 patients with 143 lesions. Preoperatively, 69% had a motor deficit and 21% were nonambulatory, with 32% due to motor weakness. At surgery, 87% of patients had hormone-refractory prostate cancer (HRPC) and 61% failed prior radiation. Median overall survival for HRPC patients was 6.6 mo (95% confidence interval [CI]: 5.6-8.6) while the median overall survival for hormone-sensitive patients was 16.3 mo (95% CI: 4.0-26.6). CONCLUSION The majority of patients undergoing surgery for prostate cancer metastases to the spine were refractory to hormone therapy, indicating that patients with hormone-sensitive prostate cancer are unlikely to develop symptomatic spinal cord compression or spinal instability. A significant number of HRPC patients presented with neurological deficits attributable to spinal cord compression. Vigilant monitoring for the development of signs and symptoms of epidural spinal cord compression and spinal instability in hormone-refractory patients is recommended. Surgical decision making may be affected by the much shorter postoperative survival for HRPC patients as compared to patients with hormone-sensitive cancer.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Sweena Kahn
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Gustav Cederquist
- Joan and Sanford I. Weill Medical College of Cornell University, New York, New York
| | - Anne S Reiner
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joseph Schwab
- Department of Orthopedic Surgery, Massachusetts General Hospital, Boston, Massachusetts
| | - Ilya Laufer
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York.,Joan and Sanford I. Weill Medical College of Cornell University, New York, New York
| | - Mark Bilsky
- Department of Neurosurgery, Memorial Sloan Kettering Cancer Center, New York, New York.,Joan and Sanford I. Weill Medical College of Cornell University, New York, New York
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Chohan MO, Berger MS. 5-Aminolevulinic acid fluorescence guided surgery for recurrent high-grade gliomas. J Neurooncol 2018; 141:517-522. [PMID: 30097823 DOI: 10.1007/s11060-018-2956-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Accepted: 07/16/2018] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Fluorescence guided surgery (FGS) with five-aminolevulinic acid (5-ALA) is expected to revolutionize neurosurgical care of patients with high-grade gliomas (HGG). After the recent landmark FDA approval, this optical agent is now available to neurosurgeons in the United States. METHODS This review is designed to highlight the evidence for the use of 5-ALA in recurrent HGG surgery for the neurosurgical community. The manuscript was prepared in accordance with the PRISMA guidelines. RESULTS Intra-operatively, a strong fluorescent signal is highly correlated with the presence of cellular tumor in recurrent HGG, giving it a high positive predictive value (PPV). Similar to what is observed in primary HGG surgery, false-negative results can occur if tumor cells do not emit fluorescence. In addition, false-positive fluorescence signals in tissues devoid of tumor cells can be observed more frequently in recurrent HGG compared to the primary setting. However, these areas overwhelmingly contain reactive/regressive tissue, resection of which is unlikely to cause functional deficits. The safety profile of 5-ALA is similarly favorable in primary and recurrent HGG. CONCLUSIONS 5-ALA FGS is a powerful adjunct in the resection of recurrent HGG with a high PPV and favorable safety profile. It is therefore the authors' opinion to routinely employ this fluorescent agent as a standard of care.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurological Surgery, University of New Mexico, 2211 Lomas Blvd. NE, Albuquerque, NM, 87111, USA.
| | - Mitchel S Berger
- Department of Neurological Surgery, University of California, San Francisco, 505 Parnassus Ave. Rm. M779, San Francisco, CA, 94143-0112, USA
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Chohan MO, Levin AM, Singh R, Zhou Z, Green CL, Kazam JJ, Tsiouris AJ, Anand VK, Schwartz TH. Three-dimensional volumetric measurements in defining endoscope-guided giant adenoma surgery outcomes. Pituitary 2016; 19:311-21. [PMID: 26843023 DOI: 10.1007/s11102-016-0709-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Maximum two-dimensional (2D) diameter has been used to define giant pituitary adenoma (GPA) surgery outcomes as has volume using an ellipsoid approximation of volumetrics. Cross sectional length can be measured in several different planes. We sought to compare the accuracy of different 2D cross sectional measurements with the 3D volumetric measurements for predicting GPA surgery outcomes. METHODS Retrospective analysis was performed on a prospectively collected database. Tumors with >3 cm diameter were identified and classified based on maximal cross sectional measurements in three separate co-axial planes, i.e. transverse (TV), antero-posterior (AP) and cranio-caudal (CC). Volume was calculated using both MRI-guided volumetrics and an ellipsoid approximation (TV × AP × CC/2). Univariate and multivariate analysis was used to evaluate the relationship between cross sectional and volumetric data and extent of resection (EOR). RESULTS In 62 subjects, median tumor volume using 3D volumetrics was 13.74 cm(3), which was overestimated by 16 % by the ellipsoid calculation (p = 0.0029), particularly for tumors >20 cm(3). Gross total resection (GTR) was 46.7 % and median EOR was 99.57 %. At 22-month follow-up, visual and anterior pituitary functions were stable (90 %) or improved (87 %). Pre-operative tumor volume >10 cm(3) (p = 0.02) and Knosp grade 3-4 (p = 0.04) were independent predictors of EOR. Knosp grade 3-4 (p < 0.0001), TV measurement >4 cm (p = 0.007) and maximum cross sectional length >4 cm (p = 0.04) were predictors of not achieving GTR. Only TV measurement (p = 0.02) predicted permanent diabetes insipidis. The smallest significant thresholds for predicting decreased GTR were TV measurement >25 mm, AP measurement >35 mm and volume >19 cm(3). CONCLUSION We propose a new volumetric threshold of 20 cm(3) as most accurate for predicting GTR in the EEA era. CC measurement is the least useful predictor. Cavernous sinus invasion remains the best predictor of incomplete resection.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, Memorial Sloan-Kettering Cancer Center, 1275 York Ave, New York, NY, 10065, USA.
- Department of Neurosurgery, University of New Mexico, Albuquerque, NM, USA.
| | - Ariana M Levin
- Joan and Sanford I. Weill Medical College of Cornell University, New York, NY, USA
| | - Ranjodh Singh
- Joan and Sanford I. Weill Medical College of Cornell University, New York, NY, USA
| | - Zhiping Zhou
- Department of Neurological Surgery, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA
| | - Carlos L Green
- Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA
| | - Jacob J Kazam
- Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA
| | - Apostolos J Tsiouris
- Department of Neuroradiology, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA
| | - Vijay K Anand
- Department of Otolaryngology-Head and Neck Surgery, New York Presbyterian Hospital, New York, NY, USA
| | - Theodore H Schwartz
- Department of Otolaryngology-Head and Neck Surgery, New York Presbyterian Hospital, New York, NY, USA
- Department of Neurological Surgery and Neuroscience, Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY, USA
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Chohan MO, Akbik OS, Ramos-Canseco J, Ramirez PM, Murray-Krezan C, Berlin T, Olin K, Taylor CL, Yonas H. A novel single twist-drill access device for multimodal intracranial monitoring: a 5-year single-institution experience. Neurosurgery 2015; 10 Suppl 3:400-11; discussion 411. [PMID: 24887290 DOI: 10.1227/neu.0000000000000451] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Multimodal intracranial monitoring in the neurosurgical patient requires insertion of probes through multiple craniostomies. OBJECTIVE To report our 5-year experience with a novel device allowing multimodal monitoring though a single twist-drill hole. METHODS All devices (Hummingbird Synergy, Innerspace) were placed at the Kocher point between 2008 and 2013 at our institution. An independent clinical research nurse prospectively collected data on all bedside placements. Placement accuracy was graded on computed tomography scan as grade 1 (ipsilateral frontal horn or third ventricle), grade 2 (contralateral lateral ventricle), and grade 3 (anywhere else). Infection was monitored with serial cerebrospinal fluid samples. RESULTS Two hundred seventy-five devices (198 at bedside, 77 in operating room) were placed in patients with spontaneous subarachnoid hemorrhage (49%), traumatic brain injury (47%), and others (4%) for a median duration of 6 days. A junior (postgraduate year 1-2), midlevel (postgraduate year 3-4), or senior resident (postgraduate year 5-6) placed 39%, 32%, and 29% of the devices, respectively. Ninety-two percent of all devices placed were draining cerebrospinal fluid, ie, were grade 1 (75%) or 2 (17%). Placement accuracy did not vary with level of training. Complications included hemorrhage (10%) and infection (4%), with 1 patient requiring intraparenchymal hematoma evacuation and a second requiring abscess drainage. These rates were lower than reported in the literature for standard external ventricular drains. CONCLUSION Hummingbird Synergy is a novel single-port access device for multimodal intracranial monitoring that can be placed safely at the bedside or in the operating room with placement accuracy and has a complication profile similar to or better than that for standard external ventricular drains.
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Affiliation(s)
- Muhammad Omar Chohan
- *Department of Neurosurgery, University of New Mexico Hospital, Albuquerque, New Mexico; ‡Division of Epidemiology, Biostatistics, and Preventive Medicine, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
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Chohan MO, Bragina O, Kazim SF, Statom G, Baazaoui N, Bragin D, Iqbal K, Nemoto E, Yonas H. Enhancement of neurogenesis and memory by a neurotrophic peptide in mild to moderate traumatic brain injury. Neurosurgery 2015; 76:201-14; discussion 214-5. [PMID: 25255260 DOI: 10.1227/neu.0000000000000577] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Traumatic brain injury (TBI) is a risk factor for Alzheimer disease (AD), a neurocognitive disorder with similar cellular abnormalities. We recently discovered a small molecule (Peptide 6) corresponding to an active region of human ciliary neurotrophic factor, with neurogenic and neurotrophic properties in mouse models of AD and Down syndrome. OBJECTIVE To describe hippocampal abnormalities in a mouse model of mild to moderate TBI and their reversal by Peptide 6. METHODS TBI was induced in adult C57Bl6 mice using controlled cortical impact with 1.5 mm of cortical penetration. The animals were treated with 50 nmol/d of Peptide 6 or saline solution for 30 days. Dentate gyrus neurogenesis, dendritic and synaptic density, and AD biomarkers were quantitatively analyzed, and behavioral tests were performed. RESULTS Ipsilateral neuronal loss in CA1 and the parietal cortex and increase in Alzheimer-type hyperphosphorylated tau and A-β were seen in TBI mice. Compared with saline solution, Peptide 6 treatment increased the number of newborn neurons, but not uncommitted progenitor cells, in dentate gyrus by 80%. Peptide 6 treatment also reversed TBI-induced dendritic and synaptic density loss while increasing activity in tri-synaptic hippocampal circuitry, ultimately leading to improvement in memory recall on behavioral testing. CONCLUSION Long-term treatment with Peptide 6 enhances the pool of newborn neurons in the dentate gyrus, prevents neuronal loss in CA1 and parietal cortex, preserves the dendritic and synaptic architecture in the hippocampus, and improves performance on a hippocampus-dependent memory task in TBI mice. These findings necessitate further inquiry into the therapeutic potential of small molecules based on neurotrophic factors.
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Affiliation(s)
- Muhammad Omar Chohan
- *Department of Neurosurgery, University of New Mexico Hospital, Albuquerque, New Mexico; ‡Department of Neurochemistry, Inge Grundke-Iqbal Floor, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, New York; §Neural and Behavioral Science Graduate Program, State University of New York (SUNY) Downstate Medical Center, Brooklyn, New York
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Chohan MO, Westhout FD, Taylor CL. Delayed rebleeding of a spontaneously thrombosed aneurysm after subarachnoid hemorrhage. Surg Neurol Int 2014; 5:42. [PMID: 24818049 PMCID: PMC4014823 DOI: 10.4103/2152-7806.129615] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 02/14/2014] [Indexed: 11/28/2022] Open
Abstract
Background: This report provides a rare documentation of spontaneous thrombosis of a ruptured aneurysm followed by delayed recanalization and subsequent rerupture. Case Description: A 47-year-old female presented with spontaneous subarachnoid hemorrhage (SAH). Four aneurysms were identified on CT angiogram including a basilar apex aneurysm, considered source of bleeding. Cerebral angiogram on postbleed day (PBD) #1 showed spontaneous thrombosis of basilar apex aneurysm. The patient was discharged to a nursing home on PBD #18 after two subsequent studies showed no recanalization of the basilar aneurysm. The patient returned on PBD #26 with a second episode of spontaneous SAH. The previously thrombosed basilar aneurysm had recanalized and reruptured, which was now treated with coil embolization. Conclusion: We are not aware of a previous report of saccular cerebral aneurysm documenting spontaneous thrombosis after SAH and recanalization with second hemorrhage. This occurrence presents a dilemma regarding the timing and frequency of subsequent cerebrovascular imaging and treatment.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, University of New Mexico, Albuquerque, New Mexico, USA
| | - Franklin D Westhout
- Department of Neurosurgery, University of New Mexico, Albuquerque, New Mexico, USA
| | - Christopher L Taylor
- Department of Neurosurgery, University of New Mexico, Albuquerque, New Mexico, USA
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Chohan MO, Sandoval D, Buchan A, Murray-Krezan C, Taylor CL. Cranial radiation exposure during cerebral catheter angiography: Table 1. J Neurointerv Surg 2013; 6:633-6. [DOI: 10.1136/neurintsurg-2013-010909] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Omar Chohan M, Iqbal K, Yonas H, Nemoto E. 163 Enhancement of Adult Hippocampal Neurogenesis by a Neurotrophic Peptide in Traumatic Brain Injury. Neurosurgery 2013. [DOI: 10.1227/01.neu.0000432754.70935.1b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Chohan MO, Carlson AP, Hart BL, Yonas H. Lack of functional patency of the lamina terminalis after fenestration following clipping of anterior circulation aneurysms. J Neurosurg 2013; 119:629-33. [PMID: 23808534 DOI: 10.3171/2013.5.jns13251] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Fenestration of the lamina terminalis (FLT) during aneurysm surgery for subarachnoid hemorrhage can, in theory, improve CSF circulation from the lateral and third ventricles to the cortical subarachnoid space, which may, in turn, decrease the incidence of hydrocephalus and vasospasm. However, the actual effects of FLT on CSF circulation have been difficult to determine, due to confounding factors. In addition, it is unclear whether the lamina terminalis remains functionally patent when the brain resumes its normal position. The goal of this study was to assess the functional patency of the fenestrated lamina terminalis in patients who underwent surgery for ruptured aneurysms. METHODS This prospective study included 15 patients who underwent surgical clipping of ruptured anterior circulation aneurysms, with FLT performed during surgery. On postoperative Day 1, the external ventricular drain of each patient was closed, and 1 ml of Omnipaque 300, an iodine based contrast agent, was injected intraventricularly, accompanied by cranial maneuvering designed to position the contrast agent adjacent to the lamina terminalis. Three to 5 minutes after cranial maneuvering, the flow of contrast agent into the basal cisterns was assessed with CT imaging. Flow was verified by an increase in Hounsfield units in a prespecified "region of interest" within the basal cisterns on the CT scan. This procedure was performed using a standardized protocol designed in consultation with the Department of Radiology and approved by the institutional review board. One patient who underwent endoscopic third ventriculostomy was recruited as a positive control to validate the technique, and 1 patient who underwent aneurysm clipping but not FLT was recruited as a negative control. RESULTS Seventeen patients consented to study participation. In the 15 patients who underwent aneurysm clipping and FLT, and the negative control patient who underwent aneurysm clipping but not FLT, the contrast agent followed the normal ventricular pathway from the lateral ventricles into the fourth ventricle, and did not appear in the basal cisterns. In the positive control patient, the contrast agent robustly and immediately filled the basal cisterns. CONCLUSIONS Fenestration of the lamina terminalis did not result in functional patency of the lamina terminalis when performed as part of surgical clipping for ruptured aneurysms.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, University of New Mexico Hospital, Albuquerque, New Mexico 87131, USA.
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Blanchard J, Chohan MO, Li B, Liu F, Iqbal K, Grundke-Iqbal I. Beneficial effect of a CNTF tetrapeptide on adult hippocampal neurogenesis, neuronal plasticity, and spatial memory in mice. J Alzheimers Dis 2012; 21:1185-95. [PMID: 20952820 DOI: 10.3233/jad-2010-1000069] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
A therapeutic strategy against cognitive disorders like Alzheimer's disease is to take advantage of the regenerative ability of the brain and the properties of neurotrophic factors to shift the balance from neurodegeneration to neurogenesis and neuronal plasticity. Although the ciliary neurotrophic factor (CNTF) has some of the required neuroprotective characteristics, its clinical use, due to its side effects, i.e., anorexia, skeletal muscle loss, hyperalgesia, cramps, and muscle pain, has not materialized. In the present study, we report that Peptide 6c (GDDL) that corresponds to CNTF amino acid residues 147-150, enhances the dentate gyrus neurogenesis and neuronal plasticity, and improves cognition without weight loss or any other apparent side effects in mice. Normal adult C57Bl6 mice received subcutaneous implants of extended release depot pellets containing vehicle or Peptide 6c for 30 days of continuous dosing. Dentate gyrus neurogenesis was assessed by stereological analysis of cells expressing neuronal markers, doublecortin and NeuN, and BrdU uptake. We found that Peptide 6c significantly increased early neuronal commitment, differentiation, and survival of newborn progenitor cells. These newborn neurons were functionally integrated into the hippocampal network, since basal expression of c-fos was enhanced and neuronal plasticity was increased, as reflected by higher expression of MAP2a,b and synaptophysin. Consequently, Peptide 6c treatment improved encoding of hippocampal-dependent information in a spatial reference memory task in mice. Overall, these findings demonstrated the therapeutic potential of Peptide 6c for regeneration of the brain and improvement of cognition.
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Affiliation(s)
- Julie Blanchard
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314, USA
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Abstract
Pediatric meningiomas are rare and account for about 1.5% of all intracranial tumors. When compared to adults, intraventricular location of childhood meningiomas is four to ten times as high. Atypical pathology of these lesions is very uncommon and indicates an aggressive nature. They are usually associated with Neurofibromatosis 2 (NF2) or previous cranial irradiation. Here, we present an interesting case of an unusually large, congenital intraventricular meningioma of atypical pathology in a 16 month old child with subsequently diagnosed NF2. A brief review of literature is also presented with this case illustration.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurosurgery, 1 University of New Mexico, Albuquerque, NM 87131-0001, USA
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Rehman T, Chohan MO, Yonas H. Diagnosis of ventriculoperitoneal shunt infection using [F-18]-FDG PET: a case report. J Neurosurg Sci 2011; 55:161-163. [PMID: 21623328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Infection of cerebrospinal fluid (CSF) shunts is a common occurrence and can often be difficult to diagnose using standard analysis of shunt fluid. This article presents the first case report on the diagnosis of a CSF shunt infection on FDG PET scan. A 26-year-old female underwent ventriculoperitoneal shunt placement after developing a pseudomeningocele subsequent to a suboccipital craniectomy for Chiari malformation. Two months later, the patient presented with abdominal pain and non-specific symptoms and was found to have a perisplenic abscess for which she was adequately treated. Failure of her symptoms to solve and an initial negative shunt CSF analysis prompted the search for other sources of infection. An FDG PET scan performed a week later found evidence of increase tracer uptake around the distal tip of the catheter and a repeat shunt CSF analysis showed evidence of CSF infection. FDG PET may be useful in diagnosing shunt related infections in case of high clinical suspicion when standard diagnostic modalities fail to diagnose hardware infection.
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Affiliation(s)
- T Rehman
- Department of Neurosurgery, MSC10 5615-1, University of New Mexico, Albuquerque, NM 87131-0001, USA
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Chohan MO, Li B, Blanchard J, Tung YC, Heaney AT, Rabe A, Iqbal K, Grundke-Iqbal I. Enhancement of dentate gyrus neurogenesis, dendritic and synaptic plasticity and memory by a neurotrophic peptide. Neurobiol Aging 2009; 32:1420-34. [PMID: 19767127 DOI: 10.1016/j.neurobiolaging.2009.08.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 08/07/2009] [Accepted: 08/17/2009] [Indexed: 10/20/2022]
Abstract
Pharmacological enhancement of hippocampal neurogenesis is a therapeutic approach for improvement of cognition in learning and memory disorders such as Alzheimer's disease. Here we report the development of an 11-mer peptide that we designed based on a biologically active region of the ciliary neurotrophic factor. This peptide, Peptide 6, induced proliferation and increased survival and maturation of neural progenitor cells into neurons in the dentate gyrus of normal adult C57BL6 mice. Furthermore, Peptide 6 increased the MAP2 and synaptophysin immunoreactivity in the dentate gyrus. Thirty-day treatment of the mice with a slow release bolus of the peptide implanted subcutaneously improved reference memory of the mice in Morris water maze. Peptide 6 has a plasma half life of over 6 h, is blood-brain barrier permeable, and acts by competitively inhibiting the leukemia inhibitory factor signaling. The fact that Peptide 6 is both neurogenic and neurotrophic and that this peptide is effective when given peripherally, demonstrates its potential for prevention and treatment of learning and memory disorders.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, Staten Island, NY 10314-6399, USA
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Shi J, Zhang T, Zhou C, Chohan MO, Gu X, Wegiel J, Zhou J, Hwang YW, Iqbal K, Grundke-Iqbal I, Gong CX, Liu F. Increased dosage of Dyrk1A alters alternative splicing factor (ASF)-regulated alternative splicing of tau in Down syndrome. J Biol Chem 2008; 283:28660-9. [PMID: 18658135 PMCID: PMC2568927 DOI: 10.1074/jbc.m802645200] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2008] [Revised: 07/14/2008] [Indexed: 12/15/2022] Open
Abstract
Two groups of tau, 3R- and 4R-tau, are generated by alternative splicing of tau exon 10. Normal adult human brain expresses equal levels of them. Disruption of the physiological balance is a common feature of several tauopathies. Very early in their life, individuals with Down syndrome (DS) develop Alzheimer-type tau pathology, the molecular basis for which is not fully understood. Here, we demonstrate that Dyrk1A, a kinase encoded by a gene in the DS critical region, phosphorylates alternative splicing factor (ASF) at Ser-227, Ser-234, and Ser-238, driving it into nuclear speckles and preventing it from facilitating tau exon 10 inclusion. The increased dosage of Dyrk1A in DS brain due to trisomy of chromosome 21 correlates to an increase in 3R-tau level, which on abnormal hyperphosphorylation and aggregation of tau results in neurofibrillary degeneration. Imbalance of 3R- and 4R-tau in DS brain by Dyrk1A-induced dysregulation of alternative splicing factor-mediated alternative splicing of tau exon 10 represents a novel mechanism of neurofibrillary degeneration and may help explain early onset tauopathy in individuals with DS.
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Affiliation(s)
- Jianhua Shi
- Jiangsu Key Laboratory of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P. R. China
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20
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Chohan MO. Novel Approaches to Alzheimer's Disease Therapeutics. J Alzheimers Dis 2008; 15:155-6. [DOI: 10.3233/jad-2008-15201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Muhammad Omar Chohan
- Neuroimmunology Lab, Department of Neurochemistry, NYS Institute for Basic Research in Developmental Disabilities Staten Island, New York, USA. E-mail:
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21
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Khawaja MR, Taj F, Saleheen D, Ahmad U, Chohan MO, Jafar T, Frossard PM. Association study of two interleukin-1 gene loci with essential hypertension in a Pakistani Pathan population. J Hum Hypertens 2007; 22:60-2. [PMID: 17611547 DOI: 10.1038/sj.jhh.1002257] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M R Khawaja
- Medical College, Faculty of Health Sciences, Aga Khan University Medical College, Karachi, Pakistan
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Li B, Chohan MO, Grundke-Iqbal I, Iqbal K. Disruption of microtubule network by Alzheimer abnormally hyperphosphorylated tau. Acta Neuropathol 2007; 113:501-11. [PMID: 17372746 PMCID: PMC3191942 DOI: 10.1007/s00401-007-0207-8] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2006] [Revised: 02/09/2007] [Accepted: 02/09/2007] [Indexed: 01/06/2023]
Abstract
Hyperphosphorylated tau has long been proposed as the key molecule disrupting normal neuronal microtubule dynamics and leading to neurofibrillary degeneration in Alzheimer disease. Here we provide a direct evidence of hyperphosphorylated tau-induced disruption of microtubule network. Using Nocodozole-treated and detergent-extracted cells, we created a neuronal environment in mouse embryonic fibroblasts, 3T3 cells, by replacing their cytoplasm with adult rat brain cytosol. By recreating neuronal microtubule network in these cells, we were able to follow the effects of hyperphosphorylated tau on microtubule dynamics in real time. Whereas recombinant human brain tau promoted assembly and bundling of microtubules, abnormally hyperphosphorylated tau isolated from Alzheimer disease brain cytosol (AD P-tau) inhibited the assembly and disrupted preformed microtubule network by sequestering normal brain tau and MAP2. This breakdown of the microtubule network was reversed by treatment of the extracted cells with protein phosphatase-2A. This study, for the first time, provides direct mechanistic insights into the molecular basis of both axonal and dendritic neurodegeneration seen in Alzheimer disease.
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Abstract
Glutamate toxicity through NMDA receptor channels has long been central to the understanding of acute neuronal injury. Recent studies implicate similar events in chronic neurodegenerative diseases. Here, we analyze some of the most intriguing evidence for NMDA receptor-mediated cellular dysfunction and propose a mechanism by which hyperactive NMDA receptors might lead to neurofibrillary degeneration in Alzheimer's disease.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314-6399, USA.
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Chohan MO, Khatoon S, Iqbal IG, Iqbal K. Involvement of I2PP2A in the abnormal hyperphosphorylation of tau and its reversal by Memantine. FEBS Lett 2006; 580:3973-9. [PMID: 16806196 DOI: 10.1016/j.febslet.2006.06.021] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 06/02/2006] [Accepted: 06/02/2006] [Indexed: 11/22/2022]
Abstract
The activity of protein phosphatase (PP)-2A, which regulates tau phosphorylation, is compromised in Alzheimer disease brain. Here we show that the transient transfection of PC12 cells with inhibitor-2 (I2PP2A) of PP2A causes abnormal hyperphosphorylation of tau at Ser396/Ser404 and Ser262/Ser356. This hyperphosphorylation of tau is observed only when a sub-cellular shift of I2PP2A takes place from the nucleus to the cytoplasm and is accompanied by cleavage of I2PP2A into a 20 kDa fragment. Memantine, an un-competitive inhibitor of N-methyl-D-aspartate receptors, inhibits this abnormal phosphorylation of tau and cell death and prevents the I2PP2A-induced inhibition of PP2A activity in vitro. These findings demonstrate novel mechanisms by which I2PP2A regulates the intracellular activity of PP2A and phosphorylation of tau, and by which Memantine modulates PP2A signaling and inhibits neurofibrillary degeneration.
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Affiliation(s)
- Muhammad Omar Chohan
- Department of Neurochemistry, New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314-6399, USA
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25
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Chohan MO, Haque N, Alonso A, El-Akkad E, Grundke-Iqbal I, Grover A, Iqbal K. Hyperphosphorylation-induced self assembly of murine tau: a comparison with human tau. J Neural Transm (Vienna) 2004; 112:1035-47. [PMID: 15583961 DOI: 10.1007/s00702-004-0241-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 10/10/2004] [Indexed: 10/26/2022]
Abstract
Alzheimer's disease-like neurofibrillary pathology is neither seen in rodents nor in transgenic animals expressing the disease causing mutant human APP or mutant human presenilins. Whether the absence of this pathology is due to inability of the murine tau to self assemble into filaments or due to some other factors is not understood. In this study, we compared recombinant murine and human taus in their ability to form filaments by AD-like hyperphosphorylation in vitro. Human and murine taus, 0N4R, were generated as recombinant proteins and phosphorylated with rat brain extract as a source of protein kinases. We found that murine tau could be hyperphosphorylated to similar stoichiometry and manner as human tau. Upon hyperphosphorylation, murine tau was able to self polymerize into bundles of paired helical filament- and straight filament-like morphology. The filaments obtained from self assembly of murine tau closely resembled those formed from identically treated human tau. Moreover, like human tau, 60-70% of murine tau aggregated on hyperphosphorylation.
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Affiliation(s)
- M O Chohan
- Department of Neurochemistry, NYS Institute for Basic Research, Staten Island, NY 10314, USA
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