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Mudgal R, Sharma S, Singh S, Ravichandiran V. The neuroprotective effect of ascorbic acid against imidacloprid-induced neurotoxicity and the role of HO-1 in mice. Front Neurol 2023; 14:1130575. [PMID: 37153653 PMCID: PMC10157196 DOI: 10.3389/fneur.2023.1130575] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/06/2023] [Indexed: 05/10/2023] Open
Abstract
Imidacloprid (IMI) is not only a neurotoxic agricultural pesticide but also a possible food contaminant. The aims of this study were to (1) explore the relationship between recurrent IMI administration and neuronal toxicity in mice and (2) evaluate the potential neuroprotective effect of ascorbic acid (AA), a substance with significant free radical scavenger and having property to block the inflammatory pathways. Mice were categorized as naïve controls (administered vehicles for 28 days); the IMI-treatment animal group (administered po 45-mg/kg body weight of IMI per day for 28 days); and the IMI + AA treatment animal group (administered the same IMI dose + 200 mg/kg of AA orally for 28 days). On day 28, memory losses were assessed using the Y-maze and novel target identification behavioral tests. Mice were sacrificed 24 h after the final IMI treatments, as well as hippocampus tissues, were utilized to determine histological assessments, oxidative stress biomarkers, and Heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf2) gene expression levels. The findings demonstrated that IMI-treated mice had substantial impairment of spatial and non-spatial memory functions, as well as reduced antioxidant enzyme and acetylcholinesterase activity. The AA neuroprotective action was achieved through the suppression of the HO-1 expression as well as the stimulation of Nrf2 expression in hippocampal tissues. In summary, recurrent IMI exposure causes oxidative stress and neurotoxicity in mice, and the administration of AA significantly reduces the IMI toxicity possibly by the activation of the HO-1/Nrf2 pathway.
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2
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Brandley ET, Kirkland AE, Baron M, Baraniuk JN, Holton KF. The Effect of the Low Glutamate Diet on the Reduction of Psychiatric Symptoms in Veterans With Gulf War Illness: A Pilot Randomized-Controlled Trial. Front Psychiatry 2022; 13:926688. [PMID: 35795023 PMCID: PMC9251130 DOI: 10.3389/fpsyt.2022.926688] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
The objective of this pilot study was to examine the effects of the low glutamate diet on anxiety, post-traumatic stress disorder (PTSD), and depression in veterans with Gulf War Illness (GWI). The low glutamate diet removes dietary excitotoxins and increases consumption of micronutrients which are protective against glutamatergic excitotoxicity. This study was registered at ClinicalTrials.gov (NCT#03342482). Forty veterans with GWI completed psychiatric questionnaires at baseline and after 1-month following the low glutamate diet. Participants were then randomized into a double-blind, placebo-controlled crossover challenge with monosodium glutamate (MSG; a dietary excitotoxin) vs. placebo over three consecutive days per week, with assessments on day three. Data were analyzed across the full sample and with participants categorized by baseline symptom severity. Pre-post-dietary intervention change scores were analyzed with Wilcoxon signed-rank tests and paired sample t-tests across the full sample, and changes across symptom severity categories were analyzed using ANOVA. Crossover challenge results were analyzed with linear mixed modeling accounting for challenge material (MSG v. placebo), sequence (MSG/placebo v. placebo/MSG), period (challenge week 1 v. week 2), pre-diet baseline symptom severity category (minimal/mild, moderate, or severe), and the challenge material*symptom severity category interaction. A random effect of ID (sequence) was also included. All three measures showed significant improvement after 1 month on the diet, with significant differences between baseline severity categories. Individuals with severe psychological symptoms at baseline showed the most improvement after 1 month on the diet, while those with minimal/mild symptoms showed little to no change. Modeling results from the challenge period demonstrated a significant worsening of anxiety from MSG in only the most severe group, with no significant effects of MSG challenge on depression nor PTSD symptoms. These results suggest that the low glutamate diet may be an effective treatment for depression, anxiety, and PTSD, but that either (a) glutamate is only a direct cause of symptoms in anxiety, or (b) underlying nutrient intake may prevent negative psychiatric effects from glutamate exposure. Future, larger scale clinical trials are needed to confirm these findings and to further explore the potential influence of increased micronutrient intake on the improvements observed across anxiety, PTSD, and depression.
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Affiliation(s)
- Elizabeth T Brandley
- Department of Health Studies, American University, Washington, DC, United States
| | - Anna E Kirkland
- Medical University of South Carolina, Charleston, SC, United States
| | - Michael Baron
- Department of Mathematics and Statistics, American University, Washington, DC, United States
| | - James N Baraniuk
- Department of Medicine, Georgetown University, Washington, DC, United States
| | - Kathleen F Holton
- Department of Health Studies, American University, Washington, DC, United States.,Department of Neuroscience, American University, Washington, DC, United States.,Center for Neuroscience and Behavior, American University, Washington, DC, United States
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3
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Holton KF. Micronutrients May Be a Unique Weapon Against the Neurotoxic Triad of Excitotoxicity, Oxidative Stress and Neuroinflammation: A Perspective. Front Neurosci 2021; 15:726457. [PMID: 34630015 PMCID: PMC8492967 DOI: 10.3389/fnins.2021.726457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 08/31/2021] [Indexed: 12/21/2022] Open
Abstract
Excitotoxicity has been implicated in many neurological disorders and is a leading cause of oxidative stress and neuroinflammation in the nervous system. Most of the research to date has focused on each of these conditions individually; however, excitotoxicity, oxidative stress, and neuroinflammation have the ability to influence one another in a self-sustaining manner, thus functioning as a "neurotoxic triad." This perspective article re-introduces the concept of the neurotoxic triad and reviews how specific dietary micronutrients have been shown to protect against not only oxidative stress, but also excitotoxicity and neuroinflammation. Future dietary interventions for neurological disorders could focus on the effects on all three aspects of the neurotoxic triad.
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Affiliation(s)
- Kathleen F Holton
- Nutritional Neuroscience Lab, Department of Health Studies, Center for Neuroscience and Behavior, American University, Washington, DC, United States
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4
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Upaganlawar AB, Wankhede NL, Kale MB, Umare MD, Sehgal A, Singh S, Bhatia S, Al-Harrasi A, Najda A, Nurzyńska-Wierdak R, Bungau S, Behl T. Interweaving epilepsy and neurodegeneration: Vitamin E as a treatment approach. Biomed Pharmacother 2021; 143:112146. [PMID: 34507113 DOI: 10.1016/j.biopha.2021.112146] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/31/2021] [Accepted: 08/31/2021] [Indexed: 12/29/2022] Open
Abstract
Epilepsy is the most common neurological disorder, affecting nearly 50 million people worldwide. The condition can be manifested either due to genetic predisposition or acquired from acute insult which leads to alteration of cellular and molecular mechanisms. Evaluating the latest and the current knowledge in regard to the mechanisms underlying molecular and cellular alteration, hyperexcitability is a consequence of an imbalanced state wherein enhance excitatory glutamatergic and reduced inhibitory GABAergic signaling is considered to be accountable for seizures associated damage. However, neurodegeneration contributing to epileptogenesis has become increasingly appreciated. The components at the helm of neurodegenerative alterations during epileptogenesis include GABAergic neuronal and receptor changes, neuroinflammation, alteration in axonal transport, oxidative stress, excitotoxicity, and other cellular as well as functional changes. Targeting neurodegeneration with vitamin E as an antioxidant, anti-inflammatory and neuroprotective may prove to be one of the therapeutic approaches useful in managing epilepsy. In this review, we discuss and converse about the seizure-induced episodes as a link for the development of neurodegenerative and pathological consequences of epilepsy. We also put forth a summary of the potential intervention with vitamin E therapy in the management of epilepsy.
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Affiliation(s)
- Aman B Upaganlawar
- SNJB's Shriman Sureshdada Jain College of Pharmacy, Neminagar, Chandwad, Nashik, Maharashtra, India
| | - Nitu L Wankhede
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra, India
| | - Mayur B Kale
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra, India
| | - Mohit D Umare
- Smt. Kishoritai Bhoyar College of Pharmacy, Kamptee, Nagpur, Maharashtra, India
| | - Aayush Sehgal
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Sukhbir Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Saurabh Bhatia
- Natural & Medical Sciences Research Centre, University of Nizwa, Nizwa, Oman
| | - Ahmed Al-Harrasi
- Natural & Medical Sciences Research Centre, University of Nizwa, Nizwa, Oman
| | - Agnieszka Najda
- Department of Vegetable Crops and Medicinal Plants, University of Life Sciences, Lublin, Poland.
| | | | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine and Pharmacy, University of Oradea, Romania
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Punjab, India.
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5
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Eastman CL, D'Ambrosio R, Ganesh T. Modulating neuroinflammation and oxidative stress to prevent epilepsy and improve outcomes after traumatic brain injury. Neuropharmacology 2020; 172:107907. [PMID: 31837825 PMCID: PMC7274911 DOI: 10.1016/j.neuropharm.2019.107907] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 11/26/2019] [Accepted: 12/05/2019] [Indexed: 12/14/2022]
Abstract
Traumatic brain injury (TBI) is a leading cause of death and disability in young adults worldwide. TBI survival is associated with persistent neuropsychiatric and neurological impairments, including posttraumatic epilepsy (PTE). To date, no pharmaceutical treatment has been found to prevent PTE or ameliorate neurological/neuropsychiatric deficits after TBI. Brain trauma results in immediate mechanical damage to brain cells and blood vessels that may never be fully restored given the limited regenerative capacity of brain tissue. This primary insult unleashes cascades of events, prominently including neuroinflammation and massive oxidative stress that evolve over time, expanding the brain injury, but also clearing cellular debris and establishing homeostasis in the region of damage. Accumulating evidence suggests that oxidative stress and neuroinflammatory sequelae of TBI contribute to posttraumatic epileptogenesis. This review will focus on possible roles of reactive oxygen species (ROS), their interactions with neuroinflammation in posttraumatic epileptogenesis, and emerging therapeutic strategies after TBI. We propose that inhibitors of the professional ROS-generating enzymes, the NADPH oxygenases and myeloperoxidase alone, or combined with selective inhibition of cyclooxygenase mediated signaling may have promise for the treatment or prevention of PTE and other sequelae of TBI. This article is part of the special issue entitled 'New Epilepsy Therapies for the 21st Century - From Antiseizure Drugs to Prevention, Modification and Cure of Epilepsy'.
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Affiliation(s)
- Clifford L Eastman
- Department of Neurological Surgery, 325 Ninth Ave., Seattle, WA, 98104, USA.
| | - Raimondo D'Ambrosio
- Department of Neurological Surgery, 325 Ninth Ave., Seattle, WA, 98104, USA; Regional Epilepsy Center, University of Washington, 325 Ninth Ave., Seattle, WA, 98104, USA
| | - Thota Ganesh
- Department of Pharmacology and Chemical Biology, Emory University School of Medicine, 1510 Clifton Rd, Atlanta, GA, 30322, Georgia.
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6
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Ballaz SJ, Rebec GV. Neurobiology of vitamin C: Expanding the focus from antioxidant to endogenous neuromodulator. Pharmacol Res 2019; 146:104321. [PMID: 31229562 DOI: 10.1016/j.phrs.2019.104321] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 06/16/2019] [Accepted: 06/18/2019] [Indexed: 01/06/2023]
Abstract
Ascorbic acid (AA) is a water-soluble vitamin (C) found in all bodily organs. Most mammals synthesize it, humans are required to eat it, but all mammals need it for healthy functioning. AA reaches its highest concentration in the brain where both neurons and glia rely on tightly regulated uptake from blood via the glucose transport system and sodium-coupled active transport to accumulate and maintain AA at millimolar levels. As a prototype antioxidant, AA is not only neuroprotective, but also functions as a cofactor in redox-coupled reactions essential for the synthesis of neurotransmitters (e.g., dopamine and norepinephrine) and paracrine lipid mediators (e.g., epoxiecoisatrienoic acids) as well as the epigenetic regulation of DNA. Although redox capacity led to the promotion of AA in high doses as potential treatment for various neuropathological and psychiatric conditions, ample evidence has not supported this therapeutic strategy. Here, we focus on some long-neglected aspects of AA neurobiology, including its modulatory role in synaptic transmission as demonstrated by the long-established link between release of endogenous AA in brain extracellular fluid and the clearance of glutamate, an excitatory amino acid. Evidence that this link can be disrupted in animal models of Huntington´s disease is revealing opportunities for new research pathways and therapeutic applications (e.g., epilepsy and pain management). In fact, we suggest that improved understanding of the regulation of endogenous AA and its interaction with key brain neurotransmitter systems, rather than administration of AA in excess, should be the target of future brain-based therapies.
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Affiliation(s)
- Santiago J Ballaz
- School of Biological Sciences and Engineering, Yachay Tech University, Urcuqui, Ecuador.
| | - George V Rebec
- Program in Neuroscience, Department Psychological & Brain Sciences, Indiana University, Bloomington, USA.
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Mi DJ, Dixit S, Warner TA, Kennard JA, Scharf DA, Kessler ES, Moore LM, Consoli DC, Bown CW, Eugene AJ, Kang JQ, Harrison FE. Altered glutamate clearance in ascorbate deficient mice increases seizure susceptibility and contributes to cognitive impairment in APP/PSEN1 mice. Neurobiol Aging 2018; 71:241-254. [PMID: 30172223 DOI: 10.1016/j.neurobiolaging.2018.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 07/31/2018] [Accepted: 08/02/2018] [Indexed: 12/24/2022]
Abstract
Ascorbate (vitamin C) is critical as a first line of defense antioxidant within the brain, and specifically within the synapse. Ascorbate is released by astrocytes during glutamate clearance and disruption of this exchange mechanism may be critical in mediating glutamate toxicity within the synapse. This is likely even more critical in neurodegenerative disorders with associated excitotoxicity and seizures, in particular Alzheimer's disease, in which ascorbate levels are often low. Using Gulo-/- mice that are dependent on dietary ascorbate, we established that low brain ascorbate increased sensitivity to kainic acid as measured via behavioral observations, electroencephalography (EEG) measurements, and altered regulation of several glutamatergic system genes. Kainic acid-induced immobility was improved in wild-type mice following treatment with ceftriaxone, which upregulates glutamate transporter GLT-1. The same effect was not observed in ascorbate-deficient mice in which sufficient ascorbate is not available for release. A single, mild seizure event was sufficient to disrupt performance in the water maze in low-ascorbate mice and in APPSWE/PSEN1dE9 mice. Together, the data support the critical role of brain ascorbate in maintaining protection during glutamatergic hyperexcitation events, including seizures. The study further supports a role for mild, subclinical seizures in cognitive decline in Alzheimer's disease.
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Affiliation(s)
- Deborah J Mi
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Shilpy Dixit
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Timothy A Warner
- Division of Neurology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John A Kennard
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Daniel A Scharf
- Undergraduate Program in Neuroscience, Vanderbilt University, Nashville, TN, USA
| | - Eric S Kessler
- Undergraduate Program in Neuroscience, Vanderbilt University, Nashville, TN, USA
| | - Lisa M Moore
- Undergraduate Program in Neuroscience, Vanderbilt University, Nashville, TN, USA
| | - David C Consoli
- Interdisciplinary Graduate Program, Vanderbilt University, Nashville, TN, USA
| | - Corey W Bown
- Interdisciplinary Graduate Program, Vanderbilt University, Nashville, TN, USA
| | - Angeline J Eugene
- Undergraduate Program in Neuroscience, Vanderbilt University, Nashville, TN, USA
| | - Jing-Qiong Kang
- Division of Neurology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Fiona E Harrison
- Division of Diabetes, Endocrinology and Metabolism, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.
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8
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Pearson-Smith JN, Patel M. Metabolic Dysfunction and Oxidative Stress in Epilepsy. Int J Mol Sci 2017; 18:ijms18112365. [PMID: 29117123 PMCID: PMC5713334 DOI: 10.3390/ijms18112365] [Citation(s) in RCA: 167] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 10/27/2017] [Accepted: 10/30/2017] [Indexed: 01/17/2023] Open
Abstract
The epilepsies are a heterogeneous group of disorders characterized by the propensity to experience spontaneous recurrent seizures. Epilepsies can be genetic or acquired, and the underlying mechanisms of seizure initiation, seizure propagation, and comorbid conditions are incompletely understood. Metabolic changes including the production of reactive species are known to result from prolonged seizures and may also contribute to epilepsy development. In this review, we focus on the evidence that metabolic and redox disruption is both cause and consequence of epileptic seizures. Additionally, we discuss the promise of targeting redox processes as a therapeutic option in epilepsy.
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Affiliation(s)
- Jennifer N Pearson-Smith
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA.
| | - Manisha Patel
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, USA.
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9
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González-Reyes S, Santillán-Cigales JJ, Jiménez-Osorio AS, Pedraza-Chaverri J, Guevara-Guzmán R. Glycyrrhizin ameliorates oxidative stress and inflammation in hippocampus and olfactory bulb in lithium/pilocarpine-induced status epilepticus in rats. Epilepsy Res 2016; 126:126-33. [PMID: 27490898 DOI: 10.1016/j.eplepsyres.2016.07.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Revised: 06/29/2016] [Accepted: 07/25/2016] [Indexed: 01/09/2023]
Abstract
Glycyrrhizin (GL) is a triterpene present in the roots and rhizomes of Glycyrrhiza glabra that has anti-inflammatory, hepatoprotective and neuroprotective effects. Recently, it was demonstrated that GL produced neuroprotective effects on the postischemic brain as well as on the kainic acid injury model in rats. In addition to this, GL also prevented excitotoxic effects on primary cultures. The aims of the present study were to evaluate GL scavenging properties and to investigate GL's effect on oxidative stress and inflammation in the lithium/pilocarpine-induced seizure model in two cerebral regions, hippocampus and olfactory bulb, at acute time intervals (3 or 24h) after status epilepticus (SE). Fluorometric methods showed that GL scavenged three reactive oxygen species: hydrogen peroxide, peroxyl radicals and superoxide anions. In contrast, GL was unable to scavenge peroxynitrite, hydroxyl radicals, singlet oxygen and 2,2-diphenil-1-picrylhydrazyl (DPPH) radicals suggesting that GL is a weak scavenger. Additionally, administration of GL (50mg/kg, i.p.) 30min before pilocarpine administration significantly suppressed oxidative stress. Moreover, malondialdehyde levels were diminished and glutathione levels were maintained at control values in both cerebral regions at 3 and 24 after SE. At 24h after SE, glutathione S-transferase and superoxide dismutase activity increased in the hippocampus, while both glutathione reductase and glutathione peroxidase activity were unchanged in the olfactory bulb at that time. In addition, GL suppressed the induction of the proinflammatory cytokines interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) in both cerebral regions evaluated. These results suggest that GL confers protection against pilocarpine damage via antioxidant and anti-inflammatory effects.
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Affiliation(s)
- Susana González-Reyes
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, México
| | - Juan Jair Santillán-Cigales
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, México
| | | | - José Pedraza-Chaverri
- Departamento de Biología, Facultad de Química, Universidad Nacional Autónoma de México (UNAM), México
| | - Rosalinda Guevara-Guzmán
- Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, México.
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10
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Lei XG, Zhu JH, Cheng WH, Bao Y, Ho YS, Reddi AR, Holmgren A, Arnér ESJ. Paradoxical Roles of Antioxidant Enzymes: Basic Mechanisms and Health Implications. Physiol Rev 2016; 96:307-64. [PMID: 26681794 DOI: 10.1152/physrev.00010.2014] [Citation(s) in RCA: 247] [Impact Index Per Article: 30.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated from aerobic metabolism, as a result of accidental electron leakage as well as regulated enzymatic processes. Because ROS/RNS can induce oxidative injury and act in redox signaling, enzymes metabolizing them will inherently promote either health or disease, depending on the physiological context. It is thus misleading to consider conventionally called antioxidant enzymes to be largely, if not exclusively, health protective. Because such a notion is nonetheless common, we herein attempt to rationalize why this simplistic view should be avoided. First we give an updated summary of physiological phenotypes triggered in mouse models of overexpression or knockout of major antioxidant enzymes. Subsequently, we focus on a series of striking cases that demonstrate "paradoxical" outcomes, i.e., increased fitness upon deletion of antioxidant enzymes or disease triggered by their overexpression. We elaborate mechanisms by which these phenotypes are mediated via chemical, biological, and metabolic interactions of the antioxidant enzymes with their substrates, downstream events, and cellular context. Furthermore, we propose that novel treatments of antioxidant enzyme-related human diseases may be enabled by deliberate targeting of dual roles of the pertaining enzymes. We also discuss the potential of "antioxidant" nutrients and phytochemicals, via regulating the expression or function of antioxidant enzymes, in preventing, treating, or aggravating chronic diseases. We conclude that "paradoxical" roles of antioxidant enzymes in physiology, health, and disease derive from sophisticated molecular mechanisms of redox biology and metabolic homeostasis. Simply viewing antioxidant enzymes as always being beneficial is not only conceptually misleading but also clinically hazardous if such notions underpin medical treatment protocols based on modulation of redox pathways.
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Affiliation(s)
- Xin Gen Lei
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Jian-Hong Zhu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Wen-Hsing Cheng
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Yongping Bao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Ye-Shih Ho
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Amit R Reddi
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Arne Holmgren
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Elias S J Arnér
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, China Agricultural University, Beijing,China; Department of Animal Science, Cornell University, Ithaca, New York; Department of Preventive Medicine, Wenzhou Medical University, Wenzhou, Zhejiang, China; Department of Food Science, Nutrition and Health Promotion, Mississippi State University, Mississippi State, Mississippi; Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, Norfolk, United Kingdom; Institute of Environmental Health Sciences, Wayne State University, Detroit, Michigan; Georgia Institute of Technology, School of Chemistry and Biochemistry, Parker Petit Institute for Bioengineering and Biosciences, Atlanta, Georgia; and Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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Afifi OK, Embaby AS. Histological Study on the Protective Role of Ascorbic Acid on Cadmium Induced Cerebral Cortical Neurotoxicity in Adult Male Albino Rats. J Microsc Ultrastruct 2016; 4:36-45. [PMID: 30023208 PMCID: PMC6014236 DOI: 10.1016/j.jmau.2015.10.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/01/2015] [Accepted: 10/11/2015] [Indexed: 12/22/2022] Open
Abstract
Cadmium (Cd) toxicity represents a worldwide problem in environmental contamination and a common cause of occupational and non-occupational neurological diseases. So, this study aimed to evaluate the histological changes induced by Cd on the cerebral cortex of adult rats and evaluating the possible ameliorating role of ascorbic acid (AA). Twenty adult male rats were divided into; control group, AA group (each rat was received a daily oral dose of 200 mg AA/kg body weight (b.w) and Cd group (each rat was received 5 mg Cd/kg b.w orally) and protective group (each rat was given AA concomitantly with Cd at the same dose, route and period of administration of the previous groups. After two months the cerebral cortexes were processed for histological examination. The cerebral cortex of Cd treated animals exhibited severe degenerative changes especially in pyramidal and granule cells. Structural changes in these cells were in the form of dilated rER and Golgi complex, swollen mitochondria and marginated nuclear chromatin. Myelinated nerve fibers displayed myelination disruption and irregular neurofilaments. The neuropil appeared vacuolated with accumulation of neuroglial cells. On the other hand, these changes were ameliorated in rats which received AA concomitantly with Cd. So, it could be concluded that AA can ameliorate the histological changes induced by Cd and this direct the attention to the antioxidants as protective measures for the neurotoxicity.
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Affiliation(s)
- Omayma Kamel Afifi
- Histology Department, Faculty of Medicine, Tanta University, Egypt, Taif University, KSA
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12
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Kim HJ, Song W, Jin EH, Kim J, Chun Y, An EN, Park S. Combined Low-Intensity Exercise and Ascorbic Acid Attenuates Kainic Acid-Induced Seizure and Oxidative Stress in Mice. Neurochem Res 2015; 41:1035-41. [PMID: 26646003 DOI: 10.1007/s11064-015-1789-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 11/23/2015] [Accepted: 11/24/2015] [Indexed: 11/29/2022]
Abstract
Physical exercise and vitamins such as ascorbic acid (ASC) have been recognized as an effective strategy in neuroprotection and neurorehabilitatioin. However, there is a need to find an efficient treatment regimen that includes ASC and low-intensity exercise to diminish the risk of overtraining and nutritional treatment by attenuating oxidative stress. In the present study, we investigated the combined effect of low-intensity physical exercise (EX) and ASC on kainic acid (KA)-induced seizure activity and oxidative stress in mice. The mice were randomly assigned into groups as follows: "KA only" (n = 11), "ASC + KA" (n = 11), "Ex + KA" (n = 11), "ASC + Ex + KA" (n = 11). In the present study, low intensity of swimming training period lasted 8 weeks and consisted of 30-min sessions daily (three times per week) without tail weighting. Although no preventive effect of low-intensity exercise or ASC on KA seizure occurrence was evident, there was a decrease of seizure activity, seizure development (latency to first seizures), and mortality in "ASC + Ex + KA" compared to "ASC + KA", "Ex + KA", and "KA only" group. In addition, a preventive synergistic coordination of low-intensity exercise and ASC was evident in glutathione peroxidase and superoxide dismutase activity compared to separate treatment. These results suggest that low-intensity exercise and ASC treatment have preventive effects on seizure activity and development with alternation of oxidative status.
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Affiliation(s)
- Hee-Jae Kim
- Health and Exercise Science Laboratory, Institute of Sports Science, Seoul National University, Seoul, Korea
| | - Wook Song
- Health and Exercise Science Laboratory, Institute of Sports Science, Seoul National University, Seoul, Korea.,Institute on Aging, Seoul National University, Seoul, Korea
| | - Eun Hee Jin
- Department of Sports Science, Sungkyunkwan University, Seoul, Korea
| | - Jongkyu Kim
- Aribio Sports Science Institute, Yong In University, Yongin, Korea
| | - Yoonseok Chun
- Sports Wellness Center, Yong In University, Yongin, Korea
| | - Eung Nam An
- Department of Sports Science, Sungkyunkwan University, Seoul, Korea
| | - Sok Park
- Division of Sports Industry and Science, Department of Sports and Health Management, Mokwon University, Taejon, Korea.
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Renaud J, Dumont F, Khelfaoui M, Foisset S, Letourneur F, Bienvenu T, Khwaja O, Dorseuil O, Billuart P. Identification of intellectual disability genes showing circadian clock-dependent expression in the mouse hippocampus. Neuroscience 2015; 308:11-50. [DOI: 10.1016/j.neuroscience.2015.08.066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Revised: 08/24/2015] [Accepted: 08/26/2015] [Indexed: 10/23/2022]
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Pearson JN, Rowley S, Liang LP, White AM, Day BJ, Patel M. Reactive oxygen species mediate cognitive deficits in experimental temporal lobe epilepsy. Neurobiol Dis 2015; 82:289-297. [PMID: 26184893 PMCID: PMC4871280 DOI: 10.1016/j.nbd.2015.07.005] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 07/06/2015] [Accepted: 07/09/2015] [Indexed: 11/08/2022] Open
Abstract
Cognitive dysfunction is an important comorbidity of temporal lobe epilepsy (TLE). However, no targeted therapies are available and the mechanisms underlying cognitive impairment, specifically deficits in learning and memory associated with TLE remain unknown. Oxidative stress is known to occur in the pathogenesis of TLE but its functional role remains to be determined. Here, we demonstrate that oxidative stress and resultant processes contribute to cognitive decline associated with epileptogenesis. Using a synthetic catalytic antioxidant, we show that pharmacological removal of reactive oxygen species (ROS) prevents 1) oxidative stress, 2) deficits in mitochondrial oxygen consumption rates, 3) hippocampal neuronal loss and 4) cognitive dysfunction without altering the intensity of the initial status epilepticus (SE) or epilepsy development in a rat model of SE-induced TLE. Moreover, the effects of the catalytic antioxidant on cognition persisted beyond the treatment period suggestive of disease-modification. The data implicate oxidative stress as a novel mechanism by which cognitive dysfunction can arise during epileptogenesis and suggest a potential disease-modifying therapeutic approach to target it.
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Affiliation(s)
- Jennifer N Pearson
- Neuroscience Program, University of Colorado, Anschutz Medical Campus, 80045, USA
| | - Shane Rowley
- Neuroscience Program, University of Colorado, Anschutz Medical Campus, 80045, USA
| | - Li-Ping Liang
- Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, 80045, USA
| | - Andrew M White
- Department of Pediatrics, University of Colorado, Anschutz Medical Campus, 80045, USA
| | - Brian J Day
- National Jewish Health, Denver, CO 80206, USA
| | - Manisha Patel
- Neuroscience Program, University of Colorado, Anschutz Medical Campus, 80045, USA; Department of Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, 80045, USA.
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Animal models of temporal lobe epilepsy following systemic chemoconvulsant administration. J Neurosci Methods 2015; 260:45-52. [PMID: 25769270 DOI: 10.1016/j.jneumeth.2015.03.009] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 03/03/2015] [Accepted: 03/04/2015] [Indexed: 01/23/2023]
Abstract
In order to understand the pathophysiology of temporal lobe epilepsy (TLE), and thus to develop new pharmacological treatments, in vivo animal models that present features similar to those seen in TLE patients have been developed during the last four decades. Some of these models are based on the systemic administration of chemoconvulsants to induce an initial precipitating injury (status epilepticus) that is followed by the appearance of recurrent seizures originating from limbic structures. In this paper we will review two chemically-induced TLE models, namely the kainic acid and pilocarpine models, which have been widely employed in basic epilepsy research. Specifically, we will take into consideration their behavioral, electroencephalographic and neuropathologic features. We will also evaluate the response of these models to anti-epileptic drugs and the impact they might have in developing new treatments for TLE.
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Martinc B, Grabnar I, Vovk T. Antioxidants as a preventive treatment for epileptic process: a review of the current status. Curr Neuropharmacol 2014; 12:527-50. [PMID: 25977679 PMCID: PMC4428026 DOI: 10.2174/1570159x12666140923205715] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Revised: 07/29/2014] [Accepted: 09/22/2014] [Indexed: 11/25/2022] Open
Abstract
Epilepsy is known as one of the most frequent neurological diseases, characterized by an enduring predisposition to generate epileptic seizures. Oxidative stress is believed to directly participate in pathways leading to neurodegeneration, which serves as the most important propagating factor, leading to the epileptic condition and cognitive decline. Moreover, there is also a growing body of evidence showing the disturbance of antioxidant system balance and consequently increased production of reactive species in patients with epilepsy. A meta-analysis, conducted in the present review confirms an association between epilepsy and increased lipid peroxidation. Furthermore, it was also shown that some of the antiepileptic drugs could potentially be responsible for additionally increased lipid peroxidation. Therefore, it is reasonable to propose that during the epileptic process neuroprotective treatment with antioxidants could lead to less sever structural damages, reduced epileptogenesis and milder cognitive deterioration. To evaluate this hypothesis studies investigating the neuroprotective therapeutic potential of various antioxidants in cells, animal seizure models and patients with epilepsy have been reviewed. Numerous beneficial effects of antioxidants on oxidative stress markers and in some cases also neuroprotective effects were observed in animal seizure models. However, despite these encouraging results, till now only a few antioxidants have been further applied to patients with epilepsy as an add-on therapy. Based on the several positive findings in animal models, a strong need for more carefully planned, randomized, double-blind, cross-over, placebo-controlled clinical trials for the evaluation of antioxidants efficacy in patients with epilepsy is warranted.
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Affiliation(s)
| | | | - Tomaž Vovk
- Faculty of Pharmacy, University of Ljubljana, Aškerčeva 7, 1000 Ljubljana, Slovenia
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Role of energy metabolic deficits and oxidative stress in excitotoxic spinal motor neuron degeneration in vivo. ASN Neuro 2014; 6:AN20130046. [PMID: 24524836 PMCID: PMC3950966 DOI: 10.1042/an20130046] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
MN (motor neuron) death in amyotrophic lateral sclerosis may be mediated by glutamatergic excitotoxicity. Previously, our group showed that the microdialysis perfusion of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionate) in the rat lumbar spinal cord induced MN death and permanent paralysis within 12 h after the experiment. Here, we studied the involvement of energy metabolic deficiencies and of oxidative stress in this MN degeneration, by testing the neuroprotective effect of various energy metabolic substrates and antioxidants. Pyruvate, lactate, β-hydroxybutyrate, α-ketobutyrate and creatine reduced MN loss by 50–65%, preserved motor function and completely prevented the paralysis. Ascorbate, glutathione and glutathione ethyl ester weakly protected against motor deficits and reduced MN death by only 30–40%. Reactive oxygen species formation and 3-nitrotyrosine immunoreactivity were studied 1.5–2 h after AMPA perfusion, during the initial MN degenerating process, and no changes were observed. We conclude that mitochondrial energy deficiency plays a crucial role in this excitotoxic spinal MN degeneration, whereas oxidative stress seems a less relevant mechanism. Interestingly, we observed a clear correlation between the alterations of motor function and the number of damaged MNs, suggesting that there is a threshold of about 50% in the number of healthy MNs necessary to preserve motor function. Mitochondrial energy substrates protect against in vivo excitotoxic spinal motor neuron degeneration and the consequent paralysis, whereas antioxidants are less efficient. These results allowed to establish a minimal threshold number of spinal motor neurons necessary to preserve motor function.
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Sawicka-Glazer E, Czuczwar SJ. Vitamin C: a new auxiliary treatment of epilepsy? Pharmacol Rep 2014; 66:529-33. [PMID: 24948051 DOI: 10.1016/j.pharep.2014.02.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 02/18/2014] [Indexed: 10/25/2022]
Abstract
Although many approaches to the therapy of epilepsy exist, most of antiepileptic drugs, beside certain and unquestioned benefits, have convinced disadvantages. That is the reason for looking for new methods of treatment. Ascorbic acid, as an antioxidant and electron donor accumulated in central nervous system, seems to take part in diminishing reactions of oxidative stress in brain and cooperate with other antioxidants like alpha-tocoferol. Vitamin C, easily transported through the blood-brain barrier, is proved to reduce injury in the hippocampus during seizures. Depending on type of seizures, it has mostly inhibitory activity and even decreases mortality. Moreover, vitamin C acts as a neuroprotective factor by consolidating cell membranes and decreasing lipid peroxidation. A possible adjunctive role of vitamin C in epileptic patients needs to be considered.
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Affiliation(s)
| | - Stanisław J Czuczwar
- Department of Pathophysiology, Medical University, Lublin, Poland; Department of Physiopathology, Institute of Rural Health, Lublin, Poland.
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Shahar E, Attias U, Savulescu D, Genizin J, Gavish M, Nagler R. Oxidative stress, metalloproteinase and LDH in children with intractable and non-intractable epilepsy as reflected in salivary analysis. Epilepsy Res 2014; 108:117-24. [DOI: 10.1016/j.eplepsyres.2013.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 09/09/2013] [Accepted: 10/13/2013] [Indexed: 12/15/2022]
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Raghu J, Raghuveer VC, Rao MC, Somayaji NS, Babu PB. The ameliorative effect of ascorbic acid and Ginkgo biloba on learning and memory deficits associated with fluoride exposure. Interdiscip Toxicol 2013; 6:217-21. [PMID: 24678261 PMCID: PMC3945761 DOI: 10.2478/intox-2013-0032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 11/25/2013] [Accepted: 11/28/2013] [Indexed: 01/23/2023] Open
Abstract
Chronic exposure to fluoride causes dental and skeletal fluorosis. Fluoride exposure is also detrimental to soft tissues and organs. The present study aimed at evaluation of the effect of Ginkgo biloba and ascorbic acid on learning and memory deficits caused by fluoride exposure. Male Wistar rats were divided into five groups (n=6). Group 1 control. Groups 2 to 5 received 100 ppm of sodium fluoride over 30 days. Groups 3, 4 and 5 were further treated for 15 days receiving respectively 1% gum acacia solution, 100 mg/kg body weight ascorbic acid, and 100mg/kg body weight Ginkgo biloba extract. After 45 days, all animals were subjected to behavioural tests. The results showed that fluoride affected learning and memory. Fluoride causes oxidative stress and neurodegeneration, thereby affecting learning and memory. Ascorbic acid and Ginkgo biloba were found to augment the reversal of learning and memory deficits caused by fluoride ingestion.
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Affiliation(s)
- Jetti Raghu
- Department of Anatomy, Melaka Manipal Medical College, Manipal University, Manipal, Karnataka, India
| | - Vasudeva C. Raghuveer
- Department of Pathology, Yenepoya Medical College, Yenepoya University, Mangalore, Karnataka, India
| | - Mallikarjuna C. Rao
- Department of Pharmacology, Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnataka, India
| | - Nagabhooshana S. Somayaji
- Department of Anatomy, Melaka Manipal Medical College, Manipal University, Manipal, Karnataka, India
| | - Prakash B. Babu
- Department of Anatomy, Kasturba Medical College, Manipal University, Manipal, Karnataka, India
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An important Indian traditional drug of ayurveda jatamansi and its substitute bhootkeshi: chemical profiling and antioxidant activity. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:142517. [PMID: 23573115 PMCID: PMC3618914 DOI: 10.1155/2013/142517] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 02/07/2013] [Indexed: 11/17/2022]
Abstract
Nardostachys jatamansi DC. and Selinum vaginatum (Edgew) Cl. are two endemic high altitude Indian medicinal plants that have been traditionally known as "Jatamansi" and "Bhootkeshi," respectively. These are used in various traditional herbal formulations and nutraceuticals, as well as to treat neurological disorders like epilepsy, hysteria, syncope, convulsions, and mental weakness. They resemble each other in their external morphological characters and characteristic odour, so their roots are often confused with each other. Since free radicals have been implicated in the pathogenesis of a considerable range of neurological disorders, including seizures and epilepsy, analysis of these two important medicinal plants was carried out based on their antioxidant activities and phenolic profiles. N. jatamansi expressed better antioxidant activity with both DPPH and TAC methods. Strong correlation was seen between TPC and antioxidant activities. Phenolic compounds such as chlorogenic acid, ferulic acid, protocatechuic acid, and syringic acid were analyzed qualitatively and quantitatively in the methanol extracts of N. jatamansi and S. vaginatum by HPLC. N. jatamansi was found to contain only protocatechuic and syringic acids while chlorogenic and ferulic acids were present only in S. vaginatum. The studies suggest that both of the plants exhibit distinctive properties and that their similar therapeutic uses may be dependent on synergistic effects exhibited by the different compounds present in them.
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Abstract
Vitamin C, or ascorbic acid, is important as an antioxidant and participates in numerous cellular functions. Although it circulates in plasma in micromolar concentrations, it reaches millimolar concentrations in most tissues. These high ascorbate cellular concentrations are thought to be generated and maintained by the SVCT2 (Slc23a2), a specific transporter for ascorbate. The vitamin is also readily recycled from its oxidized forms inside cells. Neurons in the central nervous system (CNS) contain some of the highest ascorbic acid concentrations of mammalian tissues. Intracellular ascorbate serves several functions in the CNS, including antioxidant protection, peptide amidation, myelin formation, synaptic potentiation, and protection against glutamate toxicity. The importance of the SVCT2 for CNS function is supported by the finding that its targeted deletion in mice causes widespread cerebral hemorrhage and death on post-natal day 1. Neuronal ascorbate content as maintained by this protein also has relevance for human disease, since ascorbate supplements decrease infarct size in ischemia-reperfusion injury models of stroke, and since ascorbate may protect neurons from the oxidant damage associated with neurodegenerative diseases such as Alzheimer's, Parkinson's, and Huntington's. The aim of this review is to assess the role of the SVCT2 in regulating neuronal ascorbate homeostasis and the extent to which ascorbate affects brain function and antioxidant defenses in the CNS.
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Yao JK, Keshavan MS. Antioxidants, redox signaling, and pathophysiology in schizophrenia: an integrative view. Antioxid Redox Signal 2011; 15:2011-35. [PMID: 21126177 PMCID: PMC3159108 DOI: 10.1089/ars.2010.3603] [Citation(s) in RCA: 204] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Revised: 11/26/2010] [Accepted: 12/02/2010] [Indexed: 12/19/2022]
Abstract
Schizophrenia (SZ) is a brain disorder that has been intensively studied for over a century; yet, its etiology and multifactorial pathophysiology remain a puzzle. However, significant advances have been made in identifying numerous abnormalities in key biochemical systems. One among these is the antioxidant defense system (AODS) and redox signaling. This review summarizes the findings to date in human studies. The evidence can be broadly clustered into three major themes: perturbations in AODS, relationships between AODS alterations and other systems (i.e., membrane structure, immune function, and neurotransmission), and clinical implications. These domains of AODS have been examined in samples from both the central nervous system and peripheral tissues. Findings in patients with SZ include decreased nonenzymatic antioxidants, increased lipid peroxides and nitric oxides, and homeostatic imbalance of purine catabolism. Reductions of plasma antioxidant capacity are seen in patients with chronic illness as well as early in the course of SZ. Notably, these data indicate that many AODS alterations are independent of treatment effects. Moreover, there is burgeoning evidence indicating a link among oxidative stress, membrane defects, immune dysfunction, and multineurotransmitter pathologies in SZ. Finally, the body of evidence reviewed herein provides a theoretical rationale for the development of novel treatment approaches.
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Affiliation(s)
- Jeffrey K Yao
- Medical Research Service, VA Pittsburgh Healthcare System,7180 Highland Drive, Pittsburgh, PA 15206, USA.
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Shin EJ, Jeong JH, Chung YH, Kim WK, Ko KH, Bach JH, Hong JS, Yoneda Y, Kim HC. Role of oxidative stress in epileptic seizures. Neurochem Int 2011; 59:122-37. [PMID: 21672578 PMCID: PMC3606551 DOI: 10.1016/j.neuint.2011.03.025] [Citation(s) in RCA: 294] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 03/27/2011] [Accepted: 03/28/2011] [Indexed: 11/16/2022]
Abstract
Oxidative stress resulting from excessive free-radical release is likely implicated in the initiation and progression of epilepsy. Therefore, antioxidant therapies aimed at reducing oxidative stress have received considerable attention in epilepsy treatment. However, much evidence suggests that oxidative stress does not always have the same pattern in all seizures models. Thus, this review provides an overview aimed at achieving a better understanding of this issue. We summarize work regarding seizure models (i.e., genetic rat models, kainic acid, pilocarpine, pentylenetetrazol, and trimethyltin), oxidative stress as an etiologic factor in epileptic seizures (i.e., impairment of antioxidant systems, mitochondrial dysfunction, involvement of redox-active metals, arachidonic acid pathway activation, and aging), and antioxidant strategies for seizure treatment. Combined, this review highlights pharmacological mechanisms associated with oxidative stress in epileptic seizures and the potential for neuroprotection in epilepsy that targets oxidative stress and is supported by effective antioxidant treatment.
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Affiliation(s)
- Eun-Joo Shin
- Neuropsychopharamcology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Ji Hoon Jeong
- Department of Pharmacology, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Yoon Hee Chung
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul 156-756, South Korea
| | - Won-Ki Kim
- Department of Neuroscience, College of Medicine, Korea University, Seoul 136-705, South Korea
| | - Kwang-Ho Ko
- Pharmacology Laboratory, College of Pharmacy, Seoul National University, Seoul 143-701, South Korea
| | - Jae-Hyung Bach
- Neuropsychopharamcology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
| | - Jau-Shyong Hong
- Neuropharmacology Section, Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
| | - Yukio Yoneda
- Laboratory of Molecular Pharmacology, Division of Pharmaceutical Sciences, Kanazawa University Graduate School of Natural Science and Technology, Kanazawa, Ishikawa 920-1192, Japan
| | - Hyoung-Chun Kim
- Neuropsychopharamcology and Toxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
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Folbergrová J, Kunz WS. Mitochondrial dysfunction in epilepsy. Mitochondrion 2011; 12:35-40. [PMID: 21530687 DOI: 10.1016/j.mito.2011.04.004] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 02/16/2011] [Accepted: 04/14/2011] [Indexed: 11/29/2022]
Abstract
Mitochondrial dysfunction has been identified as one potential cause of epileptic seizures. Impaired mitochondrial function has been reported for the seizure focus of patients with temporal lobe epilepsy and Ammon's horn sclerosis and of adult and immature animal models of epilepsy. Since mitochondrial oxidative phosphorylation provides the major source of ATP in neurons and mitochondria participate in cellular Ca(2+) homeostasis and generation of reactive oxygen species, their dysfunction strongly affects neuronal excitability and synaptic transmission. Therefore, mitochondrial dysfunction is proposed to be highly relevant for seizure generation. Additionally, mitochondrial dysfunction is known to trigger neuronal cell death, which is a prominent feature of therapy-resistant epilepsy. For this reason mitochondria have to be considered as promising targets for neuroprotective strategies in epilepsy.
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Affiliation(s)
- Jaroslava Folbergrová
- Department of Developmental Epileptology, Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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Sharma S, Rakoczy S, Dahlheimer K, Brown-Borg H. The hippocampus of Ames dwarf mice exhibits enhanced antioxidative defenses following kainic acid-induced oxidative stress. Exp Gerontol 2010; 45:936-49. [PMID: 20804841 PMCID: PMC6432800 DOI: 10.1016/j.exger.2010.08.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Revised: 08/09/2010] [Accepted: 08/19/2010] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The vulnerability of the hippocampus to the effects of aging has been found to be associated with a decline in growth hormone/insulin like growth factor-1 (GH/IGF-1), and an increase in oxidative stress. We have evidence that long-living GH-deficient Ames dwarf mice have enhanced antioxidant protection in the periphery but the protection in the central nervous system is less clear. MATERIAL AND METHODS In the present study, we evaluated the antioxidative defense enzyme status in the hippocampus of Ames dwarf and wild type mice at 3, 12 and 24 months of age and examined the ability of each genotype to resist kainic acid-induced (KA) oxidative stress. An equiseizure concentration of KA was administered such that both genotypes responded with similar seizure scores and lipid peroxidation. RESULTS We found that GH-sufficient wild type mice showed an increase in oxidative stress as indicated by the reduced ratio of glutathione: glutathione disulfide following KA injection while this ratio was maintained in GH-deficient Ames dwarf mice. In addition, glutathione peroxidase activity (GPx) as well as GPx1 mRNA expression was enhanced in KA-injected Ames dwarf mice but decreased in wild type mice. There was no induction of Nrf-2 (an oxidative stress-induced transcription factor) gene expression in Ames dwarf mice following KA further suggesting maintenance of antioxidant defense in GH-deficiency under oxidative stress conditions. DISCUSSION Therefore, based on equiseizure administration of KA, Ames dwarf mice have an enhanced antioxidant defense capacity in the hippocampus similar to that observed in the periphery. This improved defense capability in the brain is likely due to increased GPx availability in Ames mice and may contribute to their enhanced longevity.
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Affiliation(s)
- Sunita Sharma
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58203, USA
| | - Sharlene Rakoczy
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58203, USA
| | - Kristine Dahlheimer
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58203, USA
| | - Holly Brown-Borg
- Department of Pharmacology, Physiology and Therapeutics, University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND 58203, USA
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Wilhelm EA, Jesse CR, Roman SS, Bortolatto CF, Nogueira CW. Anticonvulsant effect of (E)-2-benzylidene-4-phenyl-1,3-diselenole in a pilocarpine model in mice. Life Sci 2010; 87:620-7. [DOI: 10.1016/j.lfs.2010.09.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 07/08/2010] [Accepted: 09/23/2010] [Indexed: 11/28/2022]
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Mitochondrial DNA Damage and the Involvement of Antioxidant Defense and Repair System in Hippocampi of Rats with Chronic Seizures. Cell Mol Neurobiol 2010; 30:947-54. [DOI: 10.1007/s10571-010-9524-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Accepted: 04/10/2010] [Indexed: 01/15/2023]
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Oxidative damage to RNA: mechanisms, consequences, and diseases. Cell Mol Life Sci 2010; 67:1817-29. [PMID: 20148281 DOI: 10.1007/s00018-010-0277-y] [Citation(s) in RCA: 230] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Revised: 12/21/2009] [Accepted: 01/18/2010] [Indexed: 12/11/2022]
Abstract
Overproduction of free radicals can damage cellular components resulting in progressive physiological dysfunction, which has been implicated in many human diseases. Oxidative damage to RNA received little attention until the past decade. Recent studies indicate that RNA, such as messenger RNA and ribosomal RNA, is very vulnerable to oxidative damage. RNA oxidation is not a consequence of dying cells but an early event involved in pathogenesis. Oxidative modification to RNA results in disturbance of the translational process and impairment of protein synthesis, which can cause cell deterioration or even cell death. In this review, we discuss the mechanisms of oxidative damage to RNA and the possible biological consequences of damaged RNA. Furthermore, we review recent evidence suggesting that oxidative damage to RNA may contribute to progression of many human diseases.
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Waldbaum S, Patel M. Mitochondria, oxidative stress, and temporal lobe epilepsy. Epilepsy Res 2010; 88:23-45. [PMID: 19850449 PMCID: PMC3236664 DOI: 10.1016/j.eplepsyres.2009.09.020] [Citation(s) in RCA: 207] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 09/18/2009] [Accepted: 09/22/2009] [Indexed: 10/20/2022]
Abstract
Mitochondrial oxidative stress and dysfunction are contributing factors to various neurological disorders. Recently, there has been increasing evidence supporting the association between mitochondrial oxidative stress and epilepsy. Although certain inherited epilepsies are associated with mitochondrial dysfunction, little is known about its role in acquired epilepsies such as temporal lobe epilepsy (TLE). Mitochondrial oxidative stress and dysfunction are emerging as key factors that not only result from seizures, but may also contribute to epileptogenesis. The occurrence of epilepsy increases with age, and mitochondrial oxidative stress is a leading mechanism of aging and age-related degenerative disease, suggesting a further involvement of mitochondrial dysfunction in seizure generation. Mitochondria have critical cellular functions that influence neuronal excitability including production of adenosine triphosphate (ATP), fatty acid oxidation, control of apoptosis and necrosis, regulation of amino acid cycling, neurotransmitter biosynthesis, and regulation of cytosolic Ca(2+) homeostasis. Mitochondria are the primary site of reactive oxygen species (ROS) production making them uniquely vulnerable to oxidative stress and damage which can further affect cellular macromolecule function, the ability of the electron transport chain to produce ATP, antioxidant defenses, mitochondrial DNA stability, and synaptic glutamate homeostasis. Oxidative damage to one or more of these cellular targets may affect neuronal excitability and increase seizure susceptibility. The specific targeting of mitochondrial oxidative stress, dysfunction, and bioenergetics with pharmacological and non-pharmacological treatments may be a novel avenue for attenuating epileptogenesis.
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Affiliation(s)
- Simon Waldbaum
- Department of Pharmaceutical Sciences University of Colorado Denver School of Pharmacy Aurora, CO 80045 U.S.A
| | - Manisha Patel
- Department of Pharmaceutical Sciences University of Colorado Denver School of Pharmacy Aurora, CO 80045 U.S.A
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Aly H, Abd-Rabboh L, El-Dib M, Nawwar F, Hassan H, Aaref M, Abdelrahman S, Elsayed A. Ascorbic acid combined with ibuprofen in hypoxic ischemic encephalopathy: a randomized controlled trial. J Perinatol 2009; 29:438-43. [PMID: 19242485 DOI: 10.1038/jp.2009.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Free oxygen radicals and proinflammatory cytokines are important causes for brain injury in neonates with hypoxic ischemic encephalopathy (HIE). Our objectives were to test the hypothesis that a combination of antioxidants (ascorbic acid) and anti-inflammatory agents (ibuprofen) can ameliorate the brain injury in HIE and improve neurodevelopmental outcomes when given to term infants immediately after birth. STUDY DESIGN In a prospective, randomized, double-blinded controlled trial, 60 asphyxiated term infants were assigned to one of two groups, intervention and control. The intervention group (n=30) received intravenous ascorbic acid and oral ibuprofen for 3 days; and the control group (n=30) received similar volumes of a placebo. We measured a panel of cytokines at enrollment and administered the treatment drugs within 2 h after birth. Neurological evaluations and developmental screenings were performed for all survivors at 6 months of age. RESULT The Intervention and Control groups did not differ in the severity of HIE at enrollment, the concentrations of IL-1 beta and IL-6, the incidence of mortality (37 vs 33%), the incidence of neurological abnormalities at hospital discharge (47 vs 55%) and the incidence of developmental delay at 6 months of age (32 vs 40%), respectively. None of the observed complications were related to intervention. Serum interleukin (IL)-1 beta and IL-6 concentrations correlated positively with the severity of HIE at birth (P<0.01), whereas only serum IL-6 correlated with neurodevelopmental outcome at 6 months (P<0.001). CONCLUSION Early administration of ascorbic acid and ibuprofen did not affect outcomes in infants with perinatal asphyxia. This study does not explain whether our intervention was not effective in blocking free radicals and inflammatory cytokines, if the dosing and route of administration were inadequate, or if other mediators existed that could have a more powerful role in brain injury during hypoxia-ischemia.
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Affiliation(s)
- H Aly
- Department of Neonatology, George Washington University and Children's National Medical Center, Washington, District of Columbia, USA.
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Wilhelm EA, Jesse CR, Bortolatto CF, Nogueira CW, Savegnago L. Anticonvulsant and antioxidant effects of 3-alkynyl selenophene in 21-day-old rats on pilocarpine model of seizures. Brain Res Bull 2009; 79:281-7. [PMID: 19480988 DOI: 10.1016/j.brainresbull.2009.03.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2008] [Revised: 03/18/2009] [Accepted: 03/23/2009] [Indexed: 11/24/2022]
Abstract
This study investigated the anticonvulsant effect of 3-alkynyl selenophene (3-ASP) on pilocarpine (PC)-, pentylenetetrazole (PTZ)- and kainic acid (KA)-induced seizures and mortality in 21-day-old rats. Rats were pretreated by oral route (p.o.) with 3-ASP (10, 25 and 50mg/kg) before intraperitoneal (i.p.) administration of PC (400mg/kg), PTZ (80 mg/kg) or KA (45 mg/kg). 3-ASP increased the latency to the seizure onset on PTZ and KA models. At the dose of 50mg/kg, 3-ASP avoided the death caused by PTZ and KA. 3-ASP (50mg/kg) abolished seizures and death induced by PC in rats. To investigate the antioxidant effect of 3-ASP on rats exposed to PC, the activity of glutathione peroxidase (GPx), glutathione-S-transferase (GST), acetylcholinesterase (AChE), Na(+)K(+)ATPase, superoxide dismutase (SOD) and catalase (CAT) as well as the levels of reactive species (RS) and ascorbic acid (AA) were determined in brains of rats. 3-ASP protected against the increase in RS levels and CAT activity induced by PC in brains of rats. The decrease in the levels of AA and inhibition of Na(+)K(+)ATPase, SOD and AChE activities caused by PC were protected by 3-ASP. Subeffective doses of 3-ASP plus diazepam, 5S,10R-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate (MK-801) or 6,7-dinitroquinoxaline-2,3-dione (DNQX) increased the latency to the seizure onset induced by PC, suggesting the involvement of ionotropic glutamatergic and GABAergic receptors in anticonvulsant action of 3-ASP. The anticonvulsant and antioxidant effects of 3-ASP in 21-day-old rats on PC model were demonstrated.
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Affiliation(s)
- Ethel A Wilhelm
- Departamento de Química, Centro de Ciências Naturais e Exatas, Universidade Federal de Santa Maria, Santa Maria, CEP 97105-900, RS, Brazil
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Kim EJ, Won R, Sohn JH, Chung MA, Nam TS, Lee HJ, Lee BH. Anti-oxidant effect of ascorbic and dehydroascorbic acids in hippocampal slice culture. Biochem Biophys Res Commun 2008; 366:8-14. [DOI: 10.1016/j.bbrc.2007.11.050] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2007] [Accepted: 11/09/2007] [Indexed: 10/22/2022]
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Ayyildiz M, Coskun S, Yildirim M, Agar E. The Effects of Ascorbic Acid on Penicillin-induced Epileptiform Activity in Rats. Epilepsia 2007; 48:1388-95. [PMID: 17433052 DOI: 10.1111/j.1528-1167.2007.01080.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE Epileptic seizure results from excessive discharge in a population of hyperexcitable neurons. A number of studies help to document the effects of active oxygen free radical scavengers such as alpha-tocopherol or ascorbic acid (vitamin C). In the present study, we examined the effects of ascorbic acid, at the six different doses, on penicillin-induced epileptiform activity. METHODS A single microinjection of penicillin (2.5 microl, 500 units, intracortically) into the left sensorimotor cortex induced epileptiform activity within 2-5 min, progressing to full seizure activity lasting approximately 3-5 h. In the first set of experiments, 30 min after penicillin injection, six different doses of ascorbic acid (25, 50, 100, 200, 400, or 800 mg/kg) were administered intraperitoneally (IP). The other group of animals received the effective dose of ascorbic acid (100 mg/kg, IP) for 7 days. Ascorbic acid administration was stopped 24 h before penicillin treatment. Another group of rats received the effective dose of ascorbic acid (100 mg/kg, IP) 30 min before penicillin treatment. In the second set of experiments, the lipid peroxidation (MDA) and reduced glutathione (GSH) levels of brain were measured in the control, control + ascorbic acid, penicillin, and penicillin + ascorbic acid groups. RESULTS Ascorbic acid, at the low dose (50, 100 mg/kg, 30 min after penicillin injection), decreased both the frequency and amplitude of penicillin-induced epileptiform activity in rats. Ascorbic acid, at intermediate doses (200, 400 mg/kg, 30 min after penicillin injection), decreased the frequency of epileptiform activity without changing the amplitude. Ascorbic acid, at the lowest dose (25 mg/kg) and highest dose (800 mg/kg) (30 min after penicillin injection), did not change either the frequency or amplitude of epileptiform activity. Ascorbic acid, at the low dose (100 mg/kg) was the most effective dose in changing the frequency and amplitude of penicillin-induced epileptiform activity. Pretreatment with ascorbic acid (100 mg/kg) 30 min before penicillin treatment caused a significant delay in the onset of penicillin-induced epileptiform activity. Pretreatment with ascorbic acid (100 mg/kg) for 7 days did not change the latency of epileptiform activity. The most effective dose of ascorbic acid (100 mg/kg) prevented both the decrease in GSH level and the increase in lipid peroxidation level (MDA) occurring after penicillin-induced epileptiform activity. CONCLUSIONS These data indicate that ascorbic acid has neuroprotective activity against penicillin-induced epileptiform electrocorticogram activity.
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Affiliation(s)
- Mustafa Ayyildiz
- Department of Physiology, Faculty of Medicine, University of Ondokuz Mayis, Samsun, Turkey
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Lo WC, Lu PJ, Ho WY, Hsiao M, Tseng CJ. Induction of Heme Oxygenase-1 Is Involved in Carbon Monoxide-Mediated Central Cardiovascular Regulation. J Pharmacol Exp Ther 2006; 318:8-16. [PMID: 16565166 DOI: 10.1124/jpet.105.099051] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Carbon monoxide (CO) has been identified as an endogenous biological messenger in the brain. Heme oxygenase (HO) catalyzes the metabolism of heme to CO and biliverdin. Previously, we have shown the involvement of CO in central cardiovascular regulation, baroreflex modulation, and glutaminergic neuro-transmission in the nucleus tractus solitarii (NTS) of rats. In this study, we examined which HO isoform could be induced after hemin injection in the NTS. We also investigated their in situ distributions in the NTS after induction. Male Sprague-Dawley rats were anesthetized with urethane, and blood pressure was monitored intra-arterially. Unilateral microinjection of hemin (1 nmol), a heme molecule cleaved by HO to yield CO, produced significant decrease in blood pressure and heart rate. These cardiovascular effects of hemin were attenuated by prior administration of HO inhibitor zinc protoporphyrin IX (ZnPPIX). Microinjection of hemin into NTS resulted in significant induction of HO-1 protein expression in situ. Pretreatment of ZnPPIX significantly inhibited the HO-1 induction after hemin injection. No significant changes of HO-2 expression were found after hemin injection and ZnPPIX pretreatment. The in situ inductions of the HO-1 protein expression were further confirmed to be in glial cells and neurons after hemin injections into the NTS. These results indicated HO-1 but not HO-2 might be responsible for the generation of CO and contribute to central control of cardiovascular effects.
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Affiliation(s)
- Wan-Chen Lo
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, 386 Ta-Chung 1st Road, Kaohsiung, Taiwan
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36
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HAMPSON AJ, GRIMALDI M, LOLIC M, WINK D, ROSENTHAL R, AXELROD J. Neuroprotective Antioxidants from Marijuanaa. Ann N Y Acad Sci 2006. [DOI: 10.1111/j.1749-6632.2000.tb06193.x] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Shin EJ, Suh SK, Lim YK, Jhoo WK, Hjelle OP, Ottersen OP, Shin CY, Ko KH, Kim WK, Kim DS, Chun W, Ali S, Kim HC. Ascorbate attenuates trimethyltin-induced oxidative burden and neuronal degeneration in the rat hippocampus by maintaining glutathione homeostasis. Neuroscience 2005; 133:715-27. [PMID: 15908128 DOI: 10.1016/j.neuroscience.2005.02.030] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2004] [Revised: 01/31/2005] [Accepted: 02/12/2005] [Indexed: 10/25/2022]
Abstract
The specific role of endogenous glutathione in response to neuronal degeneration induced by trimethyltin (TMT) in the hippocampus was examined in rats. A single injection of TMT (8 mg/kg, i.p.) produced a rapid increase in the formation of hydroxyl radical and in the levels of malondialdehyde (MDA) and protein carbonyl. TMT-induced seizure activity significantly increased after this initial oxidative stress, and remained elevated for up to 2 weeks post-TMT. Although a significant loss of hippocampal Cornus Ammonis CA1, CA3 and CA4 neurons was observed at 3 weeks post-TMT, the elevation in the level of hydroxyl radicals, MDA, and protein carbonyl had returned to near-control levels at that time. In contrast, the ratio of reduced to oxidized glutathione remained significantly decreased at 3 weeks post-TMT, and the glutathione-like immunoreactivity of the pyramidal neurons was decreased. However glutathione-positive glia-like cells proliferated mainly in the CA1, CA3, and CA4 sectors and were intensely immunoreactive. Double labeling demonstrated the co-localization of glutathione-immunoreactive glia-like cells and reactive astrocytes, as indicated by immunostaining for glial fibrillary acidic protein. This suggests that astroglial cells were mobilized to synthesize glutathione in response to the TMT insult. The TMT-induced changes in glutathione-like immunoreactivity appear to be concurrent with changes in the expression levels of glutathione peroxidase and glutathione reductase. Ascorbate treatment significantly attenuated TMT-induced seizures, as well as the initial oxidative stress, impaired glutathione homeostasis, and neuronal degeneration in a dose-dependent manner. These results suggest that ascorbate is an effective neuroprotectant against TMT. The initial oxidative burden induced by TMT may be a causal factor in the generation of seizures, prolonged disturbance of endogenous glutathione homeostasis, and consequent neuronal degeneration.
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Affiliation(s)
- E-J Shin
- Neurotoxicology Program, College of Pharmacy, Kangwon National University, Chunchon 200-701, South Korea
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Grant MM, Barber VS, Griffiths HR. The presence of ascorbate induces expression of brain derived neurotrophic factor in SH-SY5Y neuroblastoma cells after peroxide insult, which is associated with increased survival. Proteomics 2005; 5:534-40. [PMID: 15627972 DOI: 10.1002/pmic.200300924] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Oxidative stress and free radical production have been implicated in Alzheimer's disease, where low levels of the antioxidant vitamin C (ascorbate) have been shown to be associated with the disease. In this study, neuroblastoma SH-SY5Y cells were treated with hydrogen peroxide in the presence of ascorbate in order to elucidate the mechanism(s) of protection against oxidative stress afforded by ascorbate. Protein oxidation, glutathione levels, cell viability and the effects on the proteome and its oxidized counterpart were monitored. SH-SY5Y cells treated with ascorbate prior to co-incubation with peroxide showed increased viability in comparison to cells treated with peroxide alone. This dual treatment also caused an increase in protein carbonyl content and a decrease in glutathione levels within the cells. Proteins, extracted from SH-SY5Y cells that were treated with either ascorbate or peroxide alone or with ascorbate prior to peroxide, were separated by two-dimensional gel electrophoresis and analyzed for oxidation. Co-incubation for 24 hours decreased the number of oxidised proteins (e.g. acyl CoA oxidase 3) and induced brain derived neurotrophic factor (BDNF) expression. Enhanced expression of BDNF may contribute to the protective effects of ascorbate against oxidative stress in neuronal cells.
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Affiliation(s)
- Melissa M Grant
- Life and Health Sciences, Aston University, Aston Triangle, Birmingham, UK
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Muñoz AM, Rey P, Parga J, Guerra MJ, Labandeira-Garcia JL. Glial overexpression of heme oxygenase-1: a histochemical marker for early stages of striatal damage. J Chem Neuroanat 2005; 29:113-26. [PMID: 15652698 DOI: 10.1016/j.jchemneu.2004.10.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Revised: 07/31/2004] [Accepted: 10/02/2004] [Indexed: 11/19/2022]
Abstract
The level of heme oxygenase-1 (HO-1) in the normal striatum is below the limit of immunodetection. However, HO-1 is overexpressed in both neural and non-neural cells in response to a wide range of lesions. We induced different types of lesions affecting the striatal cells or the main striatal afferent systems in rats to investigate if overexpression of HO-1 could be a useful histochemical marker of striatal damage. Thirty-six hours after intrastriatal or intraventricular injection of excitotoxins that affect striatal neurons (ibotenic acid) or of neurotoxins that affect striatal dopaminergic (6-hydroxydopamine) or serotonergic (5,7-dihydroxytriptamine) afferent terminals, or after surgical lesioning of cortico-striatal projections, there was intense induction of striatal HO-1 immunoreactivity (HO-1-ir). Double immunolabeling revealed that the HO-1-ir was located in glial cells. After intrastriatal injection of ibotenic acid, a central zone of neuronal degeneration contained numerous round and pseudopodic HO-1-ir cells, and was surrounded by a ring of HO-1-ir cells, most of which were immunoreactive for astroglial markers. Intraventricular injection of neurotoxins induced astroglial HO-1-ir cells which were more evenly distributed throughout the lesioned or denervated areas. HO-1-ir microglial cells were also observed in areas subjected to mechanical damage. The HO-1-ir was markedly lower or absent 1 week after lesion, and even more so 3 weeks after, although some HO-1-ir cells were still observed after intrastriatal injection of ibotenic acid or surgical corticostriatal deafferentation. The results indicate that determination of glial HO-1-ir is a useful histochemical marker for early stages of striatal damage.
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Affiliation(s)
- Ana M Muñoz
- Laboratory of Neuroanatomy and Experimental Neurology, Department of Morphological Sciences, Faculty of Medicine, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
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Kim EJ, Park YG, Baik EJ, Jung SJ, Won R, Nahm TS, Lee BH. Dehydroascorbic acid prevents oxidative cell death through a glutathione pathway in primary astrocytes. J Neurosci Res 2005; 79:670-9. [PMID: 15668957 DOI: 10.1002/jnr.20384] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Ascorbic acid (AA) is a well-known antioxidant. It also has pro-oxidant effects, however, in the presence of free transition metals. Because of the pro-oxidant effects of AA, dehydroascorbic acid (DHA), an oxidized form of AA, has been used as a substitute for AA. DHA has been shown recently to have a protective effect in an experimental stroke model. This study was carried out to determine if DHA has different effects from AA on hydrogen peroxide (H2O2)-induced oxidative cell death in primary astrocytes. DHA was found to prevent cell death and reverse mitochondrial dysfunction after exposure to H2O2. DHA significantly increased the glutathione peroxidase (GPx) and glutathione reductase (GR) activities 1 hr after H2O2 exposure. Moreover, DHA not only reversed the decrease in the glutathione (GSH) levels, but also significantly enhanced it by stimulating the pentose phosphate pathway (PPP) 15 hr after H2O2 exposure. DHA also reduced production of reactive oxygen species (ROS) after H2O2 exposure. In contrast, AA accelerated H2O2-induced cell death. To determine if the pro-oxidant effect of AA is related to iron, the effect of AA on cell death was examined using an iron chelator, desferrioxamine. Even though co-pretreatment with AA and desferrioxamine could abrogate the aggravating effects of AA on H2O2-induced cell death at early stages, it could not prevent H2O2-induced cell death over a 24-hr period. These results suggest that DHA has distinct effects from AA and prevent H2O2-induced cell death by increasing the GSH levels mediated by the GPx and GR activities and PPP.
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Affiliation(s)
- Eun Joo Kim
- Medical Research Center, Yonsei University College of Medicine, Seoul, Korea
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Patel M. Mitochondrial dysfunction and oxidative stress: cause and consequence of epileptic seizures. Free Radic Biol Med 2004; 37:1951-62. [PMID: 15544915 DOI: 10.1016/j.freeradbiomed.2004.08.021] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2004] [Revised: 08/27/2004] [Accepted: 08/27/2004] [Indexed: 11/27/2022]
Abstract
Mitochondrial dysfunction has been implicated as a contributing factor in diverse acute and chronic neurological disorders. However, its role in the epilepsies has only recently emerged. Animal studies show that epileptic seizures result in free radical production and oxidative damage to cellular proteins, lipids, and DNA. Mitochondria contribute to the majority of seizure-induced free radical production. Seizure-induced mitochondrial superoxide production, consequent inactivation of susceptible iron-sulfur enzymes, e.g., aconitase, and resultant iron-mediated toxicity may mediate seizure-induced neuronal death. Epileptic seizures are a common feature of mitochondrial dysfunction associated with mitochondrial encephalopathies. Recent work suggests that chronic mitochondrial oxidative stress and resultant dysfunction can render the brain more susceptible to epileptic seizures. This review focuses on the emerging role of oxidative stress and mitochondrial dysfunction both as a consequence and as a cause of epileptic seizures.
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Affiliation(s)
- Manisha Patel
- Department of Pharmaceutical Sciences, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, CO 80262, USA.
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Poolos NP, Jones TD. Patch-clamp recording from neuronal dendrites. CURRENT PROTOCOLS IN NEUROSCIENCE 2004; Chapter 6:Unit 6.19. [PMID: 18428603 DOI: 10.1002/0471142301.ns0619s29] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Pyramidal neurons of the central nervous system have extensively arborized apical dendrites that contribute importantly to the signaling properties of the neuron. Recent advances in electrophysiological techniques have allowed recording from neuronal dendrites. These techniques depend on using infrared optics to visualize dendritic processes in the unstained brain slice preparation, on pipet positioning with high resolution micromanipulators, and on stringent techniques for brain slice preparation that preserved healthy dendritic processes, even in tissue from mature animals. The procedures underlying these techniques are described in this unit.
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Liang LP, Patel M. Mitochondrial oxidative stress and increased seizure susceptibility in Sod2(-/+) mice. Free Radic Biol Med 2004; 36:542-54. [PMID: 14980699 DOI: 10.1016/j.freeradbiomed.2003.11.029] [Citation(s) in RCA: 128] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2003] [Revised: 11/10/2003] [Accepted: 11/20/2003] [Indexed: 10/26/2022]
Abstract
Epileptic seizures can occur as a result of mitochondrial dysfunction. Mitochondria have vital functions such as energy generation, control of cell death, neurotransmitter synthesis, and free radical production. Which of these critical mitochondrial functions contributes to epileptic seizures is unknown. We demonstrate here that a subset of mice with partial deficiency of the mitochondrial superoxide dismutase (Sod2(-/+)) show increased incidence of spontaneous and handling-induced seizures that correlates with chronic mitochondrial oxidative stress (increased aconitase inactivation and 8-hydroxy-2'-deoxyguanosine formation in mitochondria) and diminished mitochondrial oxygen utilization. Before the age at which spontaneous seizures appear in a subset of the mice, Sod2(-/+) mice demonstrated increased susceptibility to behavioral seizures, mitochondrial aconitase inactivation, and neurodegeneration induced by the administration of kainate. These data suggest that chronic mitochondrial oxidative stress initiated by superoxide (O(2)(.-)) radicals is sufficient to increase seizure susceptibility due to aging, environmental stimulation, or excitotoxin administration. Sod2(-/+) mice showed an age-related decrease in the expression of glial glutamate transporters (GLT-1 and GLAST), suggesting that oxidant-induced inhibition of glutamate transport may play a mechanistic role in rendering some Sod2(-/+) mice susceptible to seizures. In summary, mitochondrial oxidative stress and resultant dysfunction may be an important mechanism underlying certain seizure disorders.
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Affiliation(s)
- Li-Ping Liang
- Department of Pharmaceutical Sciences, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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Schneider Oliveira M, Flávia Furian A, Freire Royes LF, Rechia Fighera M, de Carvalho Myskiw J, Gindri Fiorenza N, Mello CF. Ascorbate modulates pentylenetetrazol-induced convulsions biphasically. Neuroscience 2004; 128:721-8. [PMID: 15464280 DOI: 10.1016/j.neuroscience.2004.07.012] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2004] [Indexed: 10/26/2022]
Abstract
Ascorbate is an antioxidant vitamin that is found in high concentrations in the brain which seems to have neuroprotective properties in some experimental models of excitotoxic neurological disorders, including convulsive behavior and reactive species-related damage. In this study we tested whether ascorbate (30, 100 or 300 mg/kg, i.p.) protects against the convulsions, protein carbonylation and inhibition of Na(+),K(+)-ATPase activity induced by pentylenetetrazol (PTZ; 1.8 micromol/striatum), a classical convulsant agent that has been fairly used for the study of epilepsy and screening of new compounds with antiepileptic activity. The intrastriatal injection of PTZ caused convulsive behavior in a dose-dependent manner and an increase in the total protein carbonyl content of the injected striatum. However, duration of PTZ-induced convulsive episodes did not correlate with protein carbonyl content of the injected striatum. Ascorbate, at high doses (300 mg/kg), protected against PTZ-induced convulsions, protein carbonylation and inhibition of Na(+),K(+)-ATPase activity in the rat striatum, further suggesting a anticonvulsant and neuroprotective role for this vitamin. Conversely, intermediate doses of ascorbate (100 mg/kg) potentiated the duration of the convulsive episodes, but had no additive effects on protein carbonylation or Na(+),K(+)-ATPase activity inhibition induced by PTZ. Low doses of ascorbate (30 mg/kg) prevented PTZ-induced increase of total striatal carbonyl protein content, but did not alter PTZ-induced convulsions and Na(+),K(+)-ATPase activity inhibition. Collectively, these data indicate that the anticonvulsant activity of ascorbate is not related to its antioxidant action and support a dual role for this compound as a neuroprotective agent, since while it protects against PTZ-induced cellular oxidative damage, it has a biphasic effect on PTZ-induced convulsions.
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Affiliation(s)
- M Schneider Oliveira
- Department of Physiology, Center of Health Sciences, Federal University of Santa Maria, 97105-900 Santa Maria, RS, Brazil
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45
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El-Remessy AB, Khalil IE, Matragoon S, Abou-Mohamed G, Tsai NJ, Roon P, Caldwell RB, Caldwell RW, Green K, Liou GI. Neuroprotective effect of (-)Delta9-tetrahydrocannabinol and cannabidiol in N-methyl-D-aspartate-induced retinal neurotoxicity: involvement of peroxynitrite. THE AMERICAN JOURNAL OF PATHOLOGY 2003; 163:1997-2008. [PMID: 14578199 DOI: 10.1016/s0002-9440(10)63558-4] [Citation(s) in RCA: 167] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In glaucoma, the increased release of glutamate is the major cause of retinal ganglion cell death. Cannabinoids have been demonstrated to protect neuron cultures from glutamate-induced death. In this study, we test the hypothesis that glutamate causes apoptosis of retinal neurons via the excessive formation of peroxynitrite, and that the neuroprotective effect of the psychotropic Delta9-tetrahydroxycannabinol (THC) or nonpsychotropic cannabidiol (CBD) is via the attenuation of this formation. Excitotoxicity of the retina was induced by intravitreal injection of N-methyl-D-aspartate (NMDA) in rats, which also received 4-hydroxy-2,2,6,6-tetramethylpiperidine-n-oxyl (TEMPOL,a superoxide dismutase-mimetic), N-omega-nitro-L-arginine methyl ester (L-NAME, a nitric oxide synthase inhibitor), THC, or CBD. Retinal neuron loss was determined by TDT-mediated dUTP nick-end labeling assay, inner retinal thickness, and quantification of the mRNAs of ganglion cell markers. NMDA induced a dose- and time-dependent accumulation of nitrite/nitrate, lipid peroxidation, and nitrotyrosine (foot print of peroxynitrite), and a dose-dependent apoptosis and loss of inner retinal neurons. Treatment with L-NAME or TEMPOL protected retinal neurons and confirmed the involvement of peroxynitrite in retinal neurotoxicity. The neuroprotection by THC and CBD was because of attenuation of peroxynitrite. The effect of THC was in part mediated by the cannabinoid receptor CB1. These results suggest the potential use of CBD as a novel topical therapy for the treatment of glaucoma.
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Affiliation(s)
- Azza B El-Remessy
- Department of Pharmacology and Toxicology, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912, USA
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46
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Abstract
The activation of adenosine A1, A2 andA3 receptors can protect neurones against damage generated by mechanical or hypoxic/ischaemic insults as well as excitotoxins. A1 receptors are probably effective by suppressing transmitter release and producing neuronal hyperpolarisation. They are less likely to be of therapeutic importance due to the plethora of side effects resulting from A1 agonism, although the existence of receptor subtypes and recent synthetic chemistry efforts to increase ligand selectivity, may yet yield clinically viable compounds. Activation of A2A receptors can protect neurons, although there is much uncertainty as to whether agonists are acting centrally or via a peripheral mechanism such as altering blood flow or immune cell function. Selective antagonists at the A2A receptor, such as 4-(2-[7-amino-2-(2-furyl)(1,2,4)triazolo(2,3-a)(1,3,5)triazin-5-yl-amino]ethyl)phenol (ZM 241385) and 7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3e]-1,2,4-triazolo[1,5-c]pyrimidine (SCH 58261), can also protect against neuronal death produced by ischaemia or excitotoxicity. In addition, A2A receptor antagonists can reduce damage produced by combinations of subthreshold doses of the endogenous excitotoxin quinolinic acid and free radicals. Since the A2A receptors do not seem to be activated by normal endogenous levels of adenosine, their blockade should not generate significant side effects, so that A2A receptor antagonists appear to be promising candidates as new drugs for the prevention of neuronal damage. Adenosine A3 receptors have received less attention to date, but agonists are clearly able to afford protection against damage when administered chronically. Given the disappointing lack of success of NMDA receptor antagonists in human stroke patients, despite their early promise in animal models, it is possible that A2A receptor antagonists could have a far greater clinical utility.
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Affiliation(s)
- Trevor W Stone
- Division of Neuroscienec and Biomedical Systems, West Medical Bldg, University of Glasgow, Glasgow G12 8QQ, UK
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47
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Abstract
The mechanisms underlying the decreased vulnerability of the immature brain to seizure-induced neuronal death remain unknown. We asked whether oxidative stress plays a role in the resistance of immature animals to seizure-induced brain damage. Mitochondrial aconitase inactivation and 8-hydroxy-2-deoxyguanosine (8-OHdG) were used as indices of steady-state mitochondrial superoxide (O(2)(-)) production and oxidative DNA damage, respectively. Kainate-induced seizures resulted in increased mitochondrial aconitase inactivation and 8-OHdG formation in adult (postnatal day 30 or more), but not in immature rats (postnatal days 12 and 21). Kainate administration did not induce manganese superoxide dismutase (MnSOD) or CuZnSOD in immature or adult rats. This developmental increase in mitochondrial O(2)(-) production and oxidative DNA damage following kainate seizures suggests that mitochondrial oxidative stress may be a key factor that renders the developing brain resistant to seizure-induced brain damage.
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Affiliation(s)
- M Patel
- Department of Pharmaceutical Sciences, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Box C238, Denver, CO 80262, USA.
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48
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Li X, Huang J, May JM. Ascorbic acid spares alpha-tocopherol and decreases lipid peroxidation in neuronal cells. Biochem Biophys Res Commun 2003; 305:656-61. [PMID: 12763044 DOI: 10.1016/s0006-291x(03)00836-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ascorbic acid is considered an antioxidant in the central nervous system, but direct evidence that ascorbate protects neuronal cells from oxidant stress is lacking. Differentiated SH-SY5Y cells in culture took up ascorbic acid on the sodium-dependent vitamin C transporter Type 2 and retained it much more effectively than dehydroascorbic acid. Intracellular ascorbate spared alpha-tocopherol, both in cells loaded with alpha-tocopherol in culture and in cells under oxidant stress due to extracellular ferricyanide. Sparing of alpha-tocopherol in response to ferricyanide was associated with protection against lipid peroxidation in cell membranes. These results show that neuronal cells concentrate ascorbate, and that intracellular ascorbate, either directly or through sparing of alpha-tocopherol, protects them against oxidant stress.
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Affiliation(s)
- Xia Li
- Department of Medicine, Vanderbilt University School of Medicine, 715 Preston Research Building II, 2220 Pierce Ave., Nashville, TN 37232-6303, USA
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49
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Nakai A, Shibazaki Y, Taniuchi Y, Oya A, Asakura H, Koshino T, Araki T. Vitamins ameliorate secondary mitochondrial failure in neonatal rat brain. Pediatr Neurol 2002; 27:30-5. [PMID: 12160970 DOI: 10.1016/s0887-8994(02)00383-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recirculation after transient intrauterine ischemia has previously been found to be accompanied by secondary mitochondrial dysfunction in the immature rat brain. This study was performed to assess the efficacy of combined treatment with ascorbic acid and alpha-tocopherol in improving secondary brain damage. On the 17th day of gestation, transient intrauterine ischemia was induced by 30 minutes of uterine artery occlusion. Either vehicle, ascorbic acid, alpha-tocopherol, or combination of ascorbic acid and alpha-tocopherol was randomly administered to pregnant rats before and after occlusion. The pups were delivered by cesarean section at 21 days of gestation, and cerebral neocortical tissue was sampled. The mitochondrial respiration was measured polarographically in homogenates. In the ischemia uterine horn, mitochondrial activity of the vehicle treatment decreased significantly to 56% of nonischemic controls. Treatment with ascorbic acid or alpha-tocopherol alone demonstrated a moderate improvement of the secondary mitochondrial dysfunction to 64% and 62% of nonischemic controls, respectively. The combined treatment caused a normalization of mitochondrial activity to 91% of nonischemic controls. These results indicate that combined treatment with ascorbic acid and alpha-tocopherol has a more protective effect against secondary mitochondrial dysfunction after transient intrauterine ischemia compared with the administration of ascorbic acid or alpha-tocopherol alone.
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Affiliation(s)
- Akihito Nakai
- Tama Nagayama Hospital, Department of Obstetrics and Gynecology, Nippon Medical School, 1-7-1 Nagayama, Tama-City, Tokyo, 206-8512, Japan
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50
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Peterson SL, Morrow D, Liu S, Liu KJ. Hydroethidine detection of superoxide production during the lithium-pilocarpine model of status epilepticus. Epilepsy Res 2002; 49:226-38. [PMID: 12076844 DOI: 10.1016/s0920-1211(02)00047-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Hydroethidine is reported to be selectively oxidized to ethidium by superoxide. Using digital imaging and fluorescence microscopy it is possible to evaluate neuronal ethidium accumulation in specific brain regions of rats damaged in the lithium-pilocarpine model of status epilepticus. Intravenous or intraperitoneal administration of hydroethidine prior to 1 h of status epilepticus produced diffuse cytosolic distribution of ethidium fluorescence suggesting an increased neuronal production of superoxide that was not observed in control animals. A significantly increased number of neurons with the enhanced ethidium fluorescence was observed in parietal cortex, piriform cortex, perirhinal cortex, lateral amygdala, mediodorsal thalamus and laterodorsal thalamus, suggesting superoxide as a mechanism of neuronal injury in those regions. Other regions injured by lithium-pilocarpine seizures, such as the basolateral amygdala and hippocampus, did not demonstrate the enhanced neuronal ethidium fluorescence. In such regions it is possible that superoxide is not a mechanism of injury or that 1 h of status epilepticus is not sufficient to produce superoxide or other reactive oxygen species.
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Affiliation(s)
- Steven L Peterson
- College of Pharmacy, University of New Mexico Health Science Center, 2502 Marble Dr. NE, Albuquerque 87131-5691, USA.
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