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Nardone R, Golaszewski S, Schwenker K, Brigo F, Maccarrone M, Versace V, Sebastianelli L, Saltuari L, Höller Y. Cholinergic transmission is impaired in patients with idiopathic normal-pressure hydrocephalus: a TMS study. J Neural Transm (Vienna) 2019; 126:1073-1080. [PMID: 31227893 PMCID: PMC6647526 DOI: 10.1007/s00702-019-02036-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 06/17/2019] [Indexed: 11/26/2022]
Abstract
The pathophysiological mechanisms of cognitive and gait disturbances in subjects with normal-pressure hydrocephalus (NPH) are still unclear. Cholinergic and other neurotransmitter abnormalities have been reported in animal models of NPH. The objective of this study was to evaluate the short latency afferent inhibition (SAI), a transcranial magnetic stimulation protocol which gives the possibility to test an inhibitory cholinergic circuit in the human brain, in subjects with idiopathic NPH (iNPH). We applied SAI technique in twenty iNPH patients before ventricular shunt surgery. Besides SAI, also the resting motor threshold and the short intracortical inhibition to paired stimulation were assessed. A significant reduction of the SAI (p = 0.016), associated with a less pronounced decrease of the resting motor threshold and the short latency intracortical inhibition to paired stimulation, were observed in patients with iNPH at baseline evaluation. We also found significant (p < 0.001) correlations between SAI values and the gait function tests, as well as between SAI and the neuropsychological tests. These findings suggest that the impairment of cholinergic neurons markedly contributes to cognitive decline and gait impairment in subjects with iNPH.
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Affiliation(s)
- Raffaele Nardone
- Department of Neurology, Franz Tappeiner Hospital, Via Rossini 5, 39012, Merano, BZ, Italy.
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria.
- Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria.
| | - Stefan Golaszewski
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria
- Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria
| | - Kerstin Schwenker
- Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria
- Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria
| | - Francesco Brigo
- Department of Neurology, Franz Tappeiner Hospital, Via Rossini 5, 39012, Merano, BZ, Italy
- Department of Neuroscience, Biomedicine and Movement Science, University of Verona, Verona, Italy
| | - Miriam Maccarrone
- Department of Neurology, Franz Tappeiner Hospital, Via Rossini 5, 39012, Merano, BZ, Italy
| | - Viviana Versace
- Department of Neurorehabilitation, Hospital of Vipiteno, Vipiteno, Italy
- Research Department for Neurorehabilitation South Tyrol, Bolzano, Italy
| | - Luca Sebastianelli
- Department of Neurorehabilitation, Hospital of Vipiteno, Vipiteno, Italy
- Research Department for Neurorehabilitation South Tyrol, Bolzano, Italy
| | - Leopold Saltuari
- Department of Neurorehabilitation, Hospital of Vipiteno, Vipiteno, Italy
- Research Department for Neurorehabilitation South Tyrol, Bolzano, Italy
- Department of Neurology, Hochzirl Hospital, Zirl, Austria
| | - Yvonne Höller
- Department of Psychology, University of Akureyri, Akureyri, Iceland
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Del Bigio MR, Di Curzio DL. Nonsurgical therapy for hydrocephalus: a comprehensive and critical review. Fluids Barriers CNS 2016; 13:3. [PMID: 26846184 PMCID: PMC4743412 DOI: 10.1186/s12987-016-0025-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 01/15/2016] [Indexed: 12/13/2022] Open
Abstract
Pharmacological interventions have been tested experimentally and clinically to prevent hydrocephalus and avoid the need for shunting beginning in the 1950s. Clinical trials of varied quality have not demonstrated lasting and convincing protective effects through manipulation of cerebrospinal fluid production, diuresis, blood clot fibrinolysis, or manipulation of fibrosis in the subarachnoid compartment, although there remains some promise in the latter areas. Acetazolamide bolus seems to be useful for predicting shunt response in adults with hydrocephalus. Neuroprotection in the situation of established hydrocephalus has been tested experimentally beginning more recently. Therapies designed to modify blood flow or pulsation, reduce inflammation, reduce oxidative damage, or protect neurons are so far of limited success; more experimental work is needed in these areas. As has been recommended for preclinical studies in stroke and brain trauma, stringent conditions should be met for preclinical studies in hydrocephalus.
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Affiliation(s)
- Marc R Del Bigio
- Department of Pathology, University of Manitoba; Children's Hospital Research Institute of Manitoba, Diagnostic Services Manitoba, 401 Brodie Centre, 715 McDermot Avenue, Winnipeg, MB, R3E 3P5, Canada.
| | - Domenico L Di Curzio
- Department of Human Anatomy and Cell Science, University of Manitoba, Winnipeg, Canada.
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Levy Nogueira M, Epelbaum S, Steyaert JM, Dubois B, Schwartz L. Mechanical stress models of Alzheimer's disease pathology. Alzheimers Dement 2015; 12:324-33. [PMID: 26718585 DOI: 10.1016/j.jalz.2015.10.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Revised: 09/11/2015] [Accepted: 10/15/2015] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Extracellular accumulation of amyloid-β protein and intracellular accumulation of tau in brain tissues have been described in animal models of Alzheimer's disease (AD) and mechanical stress-based diseases of different mechanisms, such as traumatic brain injury (TBI), arterial hypertension (HTN), and normal pressure hydrocephalus (NPH). METHODS We provide a brief overview of experimental models of TBI, HTN, and NPH showing features of tau-amyloid pathology, neuroinflammation, and neuronal loss. RESULTS "Alzheimer-like" hallmarks found in these mechanical stress-based models were compared with AD features found in transgenic models. DISCUSSION The goal of this review is, therefore, to build on current concepts of onset and progression of AD lesions. We point to the importance of accumulated mechanical stress in brain as an environmental and endogenous factor that pushes protein deposition and neuronal injury over the disease threshold. We further encourage the development of preventing strategies and drug screening based on mechanical stress models.
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Affiliation(s)
- Marcel Levy Nogueira
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France.
| | - Stéphane Epelbaum
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; INSERM, CNRS, UMR-S975, Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France
| | - Jean-Marc Steyaert
- Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France
| | - Bruno Dubois
- Institut de la Mémoire et de la Maladie d'Alzheimer (IM2A), Département de Neurologie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France; Institut des Neurosciences Translationnelles de Paris (IHU-A-ICM), Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; INSERM, CNRS, UMR-S975, Institut du Cerveau et de la Moelle Epinière (ICM), Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Hôpital de la Pitié-Salpêtrière, AP-HP, Paris, France
| | - Laurent Schwartz
- Laboratoire d'informatique (LIX), UMR 7161, Ecole Polytechnique, Université Paris-Saclay, Palaiseau, France
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Di Curzio DL, Turner-Brannen E, Del Bigio MR. Oral antioxidant therapy for juvenile rats with kaolin-induced hydrocephalus. Fluids Barriers CNS 2014; 11:23. [PMID: 25324960 PMCID: PMC4199774 DOI: 10.1186/2045-8118-11-23] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/23/2014] [Indexed: 12/31/2022] Open
Abstract
Background Oxidative and nitrosylative changes have been shown to occur in conjunction with the hypoxic changes and cellular/axonal damage in hydrocephalic rodent brains. We hypothesized that antioxidant therapy would improve behavioral, neurophysiological, and/or neurobiochemical outcomes in juvenile rats following induction of hydrocephalus. Methods Three-week old rats received an injection of kaolin (aluminum silicate) into the cisterna magna. Magnetic resonance (MR) imaging was performed two weeks later to assess ventricle size and stratify rats to four treatment conditions. Rats were treated for two weeks daily with sham therapy of either oral canola oil or dextrose or experimental therapy of a low or high dose of an antioxidant mixture containing α-tocopherol, L-ascorbic acid, coenzyme Q10 (CoQ10), reduced glutathione, and reduced lipoic acid. Behavior was examined thrice weekly. Results All hydrocephalic groups lagged in weight gain in comparison to non-hydrocephalic controls, all developed significant ventriculomegaly, and all exhibited white matter destruction. Canola oil with or without the antioxidant mixture normalized antioxidant capacity in brain tissue, and the dextrose-treated rats had the greatest ventricular enlargement during the treatment period. However, there were no significant differences between the four treatment groups of hydrocephalic rats for the various behavioral tasks. Glial fibrillary acidic protein and myelin basic protein quantitation showed no differences between the treatment groups or with control rats. There was increased lipid peroxidation in the hydrocephalic rats compared to controls but no differences between treatment groups. Conclusion The antioxidant cocktail showed no therapeutic benefits for juvenile rats with kaolin-induced hydrocephalus although canola oil might have mild benefit.
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Affiliation(s)
- Domenico L Di Curzio
- Departments of Human Anatomy & Cell Science, 715 McDermot Avenue, Winnipeg, MB R3E 3P4, Canada ; Manitoba Institute of Child Health, 715 McDermot Avenue, Winnipeg, MB R3E 3P4, Canada
| | - Emily Turner-Brannen
- Manitoba Institute of Child Health, 715 McDermot Avenue, Winnipeg, MB R3E 3P4, Canada
| | - Marc R Del Bigio
- Manitoba Institute of Child Health, 715 McDermot Avenue, Winnipeg, MB R3E 3P4, Canada ; Department of Pathology, University of Manitoba, 727 McDermot Avenue, Winnipeg, R3E 3P5, Canada
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Camellia sinensis neuroprotective role in experimentally induced hydrocephalus in Wistar rats. Childs Nerv Syst 2014; 30:591-7. [PMID: 24005799 DOI: 10.1007/s00381-013-2262-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2013] [Accepted: 08/05/2013] [Indexed: 12/18/2022]
Abstract
PURPOSE This study tested possible neuroprotective effects of Camellia sinensis-extracted polyphenols in experimental hydrocephalus in young rats. METHODS Seven-day-old Wistar rats were used in this study. Pups were subjected to hydrocephalus induction by 20 % kaolin intracisternal injection. The polyphenol was administered intraperitoneally for 9 or 20 days from the induction of hydrocephalus. Clinical observations and behavioral tests were performed once a day. The animals, deeply anesthetized, were sacrificed by cardiac perfusion with saline 10 or 21 days after induction of hydrocephalus and their brains were removed. Preparations were made for histological analysis by hematoxylin and eosin, solochrome-cyanine, and immunohistochemistry for GFAP. RESULTS Histopathological analysis showed that animals treated with the polyphenol for 9 consecutive days displayed reduction on astrocyte activity on the corpus callosum and external capsule, shown by GFAP immunostaining. They also displayed thicker and myelinated corpus callosum, exhibiting a more intense solochrome-cyanine blue staining. CONCLUSION Although these results demonstrate a possible neuroprotective effect at the initial onset of the disease, additional studies should be performed to obtain an effective and safe therapy for deeper studies in clinical trials.
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McMullen AB, Baidwan GS, McCarthy KD. Morphological and behavioral changes in the pathogenesis of a novel mouse model of communicating hydrocephalus. PLoS One 2012; 7:e30159. [PMID: 22291910 PMCID: PMC3265463 DOI: 10.1371/journal.pone.0030159] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Accepted: 12/14/2011] [Indexed: 11/18/2022] Open
Abstract
The Ro1 model of hydrocephalus represents an excellent model for studying the pathogenesis of hydrocephalus due to its complete penetrance and inducibility, enabling the investigation of the earliest cellular and histological changes in hydrocephalus prior to overt pathology. Hematoxylin and eosin staining, immunofluorescence and electron microscopy were used to characterize the histopathological events of hydrocephalus in this model. Additionally, a broad battery of behavioral tests was used to investigate behavioral changes in the Ro1 model of hydrocephalus. The earliest histological changes observed in this model were ventriculomegaly and disorganization of the ependymal lining of the aqueduct of Sylvius, which occurred concomitantly. Ventriculomegaly led to thinning of the ependyma, which was associated with periventricular edema and areas of the ventricular wall void of cilia and microvilli. Ependymal denudation was subsequent to severe ventriculomegaly, suggesting that it is an effect, rather than a cause, of hydrocephalus in the Ro1 model. Additionally, there was no closure of the aqueduct of Sylvius or any blockages within the ventricular system, even with severe ventriculomegaly, suggesting that the Ro1 model represents a model of communicating hydrocephalus. Interestingly, even with severe ventriculomegaly, there were no behavioral changes, suggesting that the brain is able to compensate for the structural changes that occur in the pathogenesis of hydrocephalus if the disorder progresses at a sufficiently slow rate.
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MESH Headings
- Animals
- Behavior, Animal/physiology
- Brain/pathology
- Brain/physiopathology
- Brain/ultrastructure
- Cardiomegaly/pathology
- Cerebral Aqueduct/pathology
- Cerebral Aqueduct/ultrastructure
- Cerebral Ventricles/pathology
- Cerebral Ventricles/ultrastructure
- Disease Models, Animal
- Hydrocephalus/complications
- Hydrocephalus/genetics
- Hydrocephalus/pathology
- Hydrocephalus/physiopathology
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Microscopy, Electron
- Receptors, Opioid, kappa/genetics
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, kappa/physiology
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Affiliation(s)
- Allison B. McMullen
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Gurlal S. Baidwan
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Ken D. McCarthy
- Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- * E-mail:
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Zhao J, Del Bigio MR, Weiler HA. Maternal arachidonic acid supplementation improves neurodevelopment in young adult offspring from rat dams with and without diabetes. Prostaglandins Leukot Essent Fatty Acids 2011; 84:63-70. [PMID: 20888744 DOI: 10.1016/j.plefa.2010.08.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 08/26/2010] [Accepted: 08/27/2010] [Indexed: 11/20/2022]
Abstract
Maternal diabetes may compromise infant arachidonic acid (AA) status and development. This study tested if maternal AA supplementation improves neurodevelopment in adult offspring. Rat dams were randomized into 6 groups: Saline-Placebo, streptozotocin-induced diabetes with glucose controlled at <13mmol/L, or poorly controlled at 13-20mmol/L using insulin; and fed either a Control or AA (0.5% fat) diet throughout reproduction. Weaned-offspring were fed regular chow to 12 weeks of age. Testing included exploratory behavior, rota rod and water maze (WM). Poorly controlled offspring showed longer (p≤0.018) escape-latency on testing-day 1 WM but not thereafter (p>0.05). Maternal glucose concentration positively correlated with (p=0.006) male offspring testing-day 1 WM latency. The AA-diet offspring performed better in WM and rota rod (p≤0.032) and showed higher exploratory behavior (p=0.008) than Control-diet offspring. These data suggest maternal hyperglycemia has longstanding consequences to initial stages of learning in the offspring. Maternal AA supplementation and training positively influence learning outcomes.
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Affiliation(s)
- Jinping Zhao
- School of Dietetics and Human Nutrition, McGill University, Ste-Anne-de-Bellevue, QC, Canada H9X 3V9
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8
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McAllister JP, Miller JM. Minocycline inhibits glial proliferation in the H-Tx rat model of congenital hydrocephalus. Cerebrospinal Fluid Res 2010; 7:7. [PMID: 20507614 PMCID: PMC2889858 DOI: 10.1186/1743-8454-7-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 05/27/2010] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Reactive astrocytosis and microgliosis are important features of the pathophysiology of hydrocephalus, and persistent glial "scars" that form could exacerbate neuroinflammation, impair cerebral perfusion, impede neuronal regeneration, and alter biomechanical properties. The purpose of this study was to determine the efficacy of minocycline, an antibiotic known for its anti-inflammatory properties, to reduce gliosis in the H-Tx rat model of congenital hydrocephalus. METHODS Minocycline (45 mg/kg/day i.p. in 5% sucrose at a concentration of 5-10 mg/ml) was administered to hydrocephalic H-Tx rats from postnatal day 15 to day 21, when ventriculomegaly had reached moderate to severe stages. Treated animals were compared to age-matched non-hydrocephalic and untreated hydrocephalic littermates. The cerebral cortex (both gray matter laminae and white matter) was processed for immunohistochemistry (glial fibrillary acidic protein, GFAP, for astrocytes and ionized calcium binding adaptor molecule, Iba-1, for microglia) and analyzed by qualitative and quantitative light microscopy. RESULTS The mean number of GFAP-immunoreactive astrocytes was significantly higher in untreated hydrocephalic animals compared to both types of controls (p < 0.001). Minocycline treatment of hydrocephalic animals reduced the number of GFAP immunoreactive cells significantly (p < 0.001). Likewise, the mean number of Iba-1 immunoreactive microglia was significantly higher in untreated hydrocephalic animals compared to both types of controls (p < 0.001). Furthermore, no differences in the numbers of GFAP-positive astrocytes or Iba-1-positive microglia were noted between control animals receiving no minocycline and control animals receiving minocycline, suggesting that minocycline does not produce an effect under non-injury conditions. Additionally, in six out of nine regions sampled, hydrocephalic animals that received minocycline injections had significantly thicker cortices when compared to their untreated hydrocephalic littermates. CONCLUSIONS Overall, these data suggest that minocycline treatment is effective in reducing the gliosis that accompanies hydrocephalus, and thus may provide an added benefit when used as a supplement to ventricular shunting.
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Affiliation(s)
- James P McAllister
- Department of Biology, Central Michigan University, Mt, Pleasant, MI 48859, USA.
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Kondziella D, Sonnewald U, Tullberg M, Wikkelso C. Brain metabolism in adult chronic hydrocephalus. J Neurochem 2008; 106:1515-24. [PMID: 18419769 DOI: 10.1111/j.1471-4159.2008.05422.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Normal pressure hydrocephalus (NPH) is the most frequent form of chronic hydrocephalus in adults. NPH remains underdiagnosed although between 5% and 10% of all demented patients may suffer from this disorder. As dementia is an increasing demographic problem, treatable forms such as in NPH have become a central issue in neurology. Despite the traditional perception of hydrocephalus being a disorder of disturbed CSF dynamics, in NPH metabolic impairment seems at least as important. So far, the only valid animal model of NPH is chronic adult kaolin hydrocephalus. In this model, opening of alternative CSF outflow pathways leads to normal or near-normal intracranial pressure and CSF outflow resistance. Yet, various metabolic disturbances cause ongoing ventricular enlargement and characteristic symptoms including cognitive decline and gait ataxia. Delayed hippocampal neuronal death, accumulation of beta-amyloid and disturbed cholinergic neurotransmission may contribute to memory dysfunction. Compromised periventricular blood flow, decreased dopamine levels in the substantia nigra and damaged striatal GABAergic interneurons may reflect basal ganglia symptoms. At least in human hydrocephalus cerebrovascular co-morbidity of the white matter plays an important role as well. It seems that in hydrocephalus from a certain 'point of no return' metabolic impairment becomes decoupled from CSF dynamics and, at least partly, self-sustained. This is probably the reason why despite restored CSF circulation by shunting many patients with chronic hydrocephalus still suffer from severe neurological deficits. The present paper offers a comprehensive review of the experimental and clinical data suggesting metabolic disturbances in chronic hydrocephalus.
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Affiliation(s)
- Daniel Kondziella
- Department of Neurology, Sahlgrenska University Hospital, Göteborg, Sweden.
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Abstract
The literature concerning brain damage due to hydrocephalus, especially in children and animal models, is reviewed. The following conclusions are reached: 1. Hydrocephalus has a deleterious effect on brain that is dependent on magnitude and duration of ventriculomegaly and modified by the age of onset. 2. Animal models have many histopathological similarities to humans and can be used to understand the pathogenesis of brain damage. 3. Periventricular axons and myelin are the primary targets of injury. The pathogenesis has similarities to traumatic and ischemic white matter injury. Secondary changes in neurons reflect compensation to the stress or ultimately the disconnection. 4. Altered efflux of extracellular fluid could result in accumulation of waste products that might interfere with neuron function. Further research is needed in this as well as the blood-brain barrier in hydrocephalus. 5. Some, but not all, of the changes are preventable by shunting CSF. However, axon loss cannot be reversed, therefore shunting in a given case must be considered carefully. 6. Experimental work has so far failed to show any benefit in reducing CSF production. Pharmacologic protection of the brain, at least as a temporary measure, holds some promise but more pre-clinical research is required.
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Affiliation(s)
- Marc R Del Bigio
- Department of Pathology, University of Manitoba, and Manitoba Institute for Child Health, Winnipeg, Canada.
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Khan OH, Enno T, Del Bigio MR. Tacrolimus and cyclosporine A are of no benefit to young rats with kaolin-induced hydrocephalus. Pediatr Neurosurg 2003; 39:309-13. [PMID: 14734865 DOI: 10.1159/000075259] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2003] [Accepted: 05/27/2003] [Indexed: 11/19/2022]
Abstract
Hydrocephalus causes damage to periventricular axons. Tacrolimus, cyclosporine A (CsA) and calpain inhibitors have been shown to protect axons in rat models of acute traumatic brain injury. We hypothesized that these agents would ameliorate the axon damage and behavioral effects in experimental hydrocephalus. Hydrocephalus was induced in 3-week-old rats by injection of kaolin into the cisterna magna. Tests of cognitive and motor function were performed on a weekly basis. In a blinded and randomized manner, tacrolimus (FK506; 3.6 mg/kg body weight) or CsA (10 mg/kg) was administered once daily by subcutaneous injection for 2 weeks, beginning 2 weeks after induction of hydrocephalus. In a separate experiment, calpain inhibitor I (10 mg/kg/day) was administered by continuous subcutaneous infusion. The brains were subjected to histopathological and biochemical analyses after 2 weeks of treatment. There was no statistically significant protection in regard to behavior, brain structure or brain composition in any of the experiments. However, there was biochemical and histological evidence of renal injury following chronic tacrolimus and CsA administration. Calcineurin inhibition does not offer significant protection in this rat model of hydrocephalus.
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Affiliation(s)
- Osaama H Khan
- Department of Pathology, University of Manitoba and Manitoba Institute for Child Health, 70 Bannatyne Avenue, Winnipeg, Manitoba R3E 0W3, Canada
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