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Domouky AM, Samy WM, Rashad WA. Therapeutic effect of the mesenchymal stem cells on vigabatrin-induced retinopathy in adult male albino rat. Anat Cell Biol 2022; 55:217-228. [PMID: 35773221 PMCID: PMC9256488 DOI: 10.5115/acb.22.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/25/2022] [Accepted: 03/06/2022] [Indexed: 12/02/2022] Open
Abstract
Vigabatrin (VGB) is an effective antiepileptic drug used mainly to treat infantile spasms and refractory complex partial seizures. However, using VGB was restricted as it was known to cause retinal toxicity that appears as a severe peripheral visual field defect. Accordingly, this study was conducted to examine the histopathological and biochemical effects of VGB on the retina in adult male albino rats and assess the possible therapeutic role of mesenchymal stem cells (MSCs) against this potential toxicity. The rats were divided into three groups (control group, VGB group, and VGB/MSCs group), one week after 65 days of VGB treatment ±MSCs. The right eyeballs were prepared for histological and immunohistochemical examination, whereas the left eyeballs were prepared for real-time polymerase chain reaction analysis. Our results demonstrated that MSCs ameliorated retinal pathological changes and downregulated the expression of glial fibrillary acidic protein, vascular endothelial growth factor, and synaptophysin after VGB administration suggesting MSCs function and vascular modulating effect. Moreover, MSCs regulate retinal tissue gene expression of BAX, Bcl-2, BDNF, NGF, synapsin, interleukin (IL)-6, IL-1β, and occludin suggesting MSCs antiapoptotic and immunomodulating effect. In conclusion, MSCs administration could be a suitable therapeutic line to ameliorate VGB-induced retinopathy.
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Affiliation(s)
- Ayat Mahmoud Domouky
- Department of Human Anatomy & Embryology, Faculty of Medicine, Zagazig University, Zagazig, Zagazig, Egypt
| | - Walaa M Samy
- Department of Medical Biochemistry, Faculty of Medicine, Zagazig University, Zagazig, Egypt
| | - Walaa A Rashad
- Department of Human Anatomy & Embryology, Faculty of Medicine, Zagazig University, Zagazig, Zagazig, Egypt
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O'Neill EK, Smith R. Visual electrophysiology in the assessment of toxicity and deficiency states affecting the visual system. Eye (Lond) 2021; 35:2344-2353. [PMID: 34290445 PMCID: PMC8377028 DOI: 10.1038/s41433-021-01663-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 02/07/2023] Open
Abstract
Visual disturbance or visual failure due to toxicity of an ingested substance or a severe nutritional deficiency can present significant challenges for diagnosis and management, for instance, where an adverse reaction to a prescribed medicine is suspected. Objective assessment of visual function is important, particularly where structural changes in the retina or optic nerve have not yet occurred, as there may be a window of opportunity to mitigate or reverse visual loss. This paper reviews a number of clinical presentations where visual electrophysiological assessment has an important role in early diagnosis or management alongside clinical assessment and ocular imaging modalities. We highlight the importance of vitamin A deficiency as an easily detected marker for severe combined micronutrient deficiency.
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Affiliation(s)
- Emily K O'Neill
- Clinical and Academic Department of Ophthalmology, Great Ormond Street Hospital for Children, London, UK. Emily.O'
| | - Richard Smith
- Eye Department, Stoke Mandeville Hospital, Aylesbury, Buckinghamshire, UK.
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3
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Ahmad R, Mehta H. The ocular adverse effects of oral drugs. Aust Prescr 2021; 44:129-136. [PMID: 34421178 PMCID: PMC8377292 DOI: 10.18773/austprescr.2021.028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Some commonly prescribed drugs have ocular adverse effects. Many parts of the eye can be affected by oral drugs. Some ocular adverse effects may be reversed with medical or surgical intervention whereas other drugs may cause irreversible loss of vision The risk of visual loss can be reduced by a number of approaches, including monitoring for ocular toxicity, reducing the drug dose, or stopping the drug and looking for an alternative. This can be supported by good communication between the prescribing clinician and ophthalmologist Infrequent or delayed ocular adverse effects may not be identified in clinical trials of new drugs. Reporting adverse events is therefore important
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Affiliation(s)
| | - Hemal Mehta
- Strathfield Retina Clinic, Sydney.,Save Sight Registries, University of Sydney
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Walters D, Vogel KR, Brown M, Shi X, Roullet JB, Gibson KM. Transcriptome analysis in mice treated with vigabatrin identifies dysregulation of genes associated with retinal signaling circuitry. Epilepsy Res 2020; 166:106395. [PMID: 32679486 DOI: 10.1016/j.eplepsyres.2020.106395] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/02/2020] [Accepted: 06/09/2020] [Indexed: 10/24/2022]
Abstract
Vigabatrin (VGB; γ-vinyl-GABA) is an antiepileptic drug that elevates CNS GABA via irreversible inactivation of the GABA catabolic enzyme GABA-transaminase. VGB's clinical utility, however, can be curtailed by peripheral visual field constriction (pVFC) and thinning of the retinal nerve fiber layer (RNFL). Earlier studies from our laboratory revealed disruptions of autophagy by VGB. Here, we tested the hypothesis that VGB administration to animals would reveal alterations of gene expression in VGB-treated retina that associated with autophagy. VGB (140 mg/kg/d; subcutaneous minipump) was continuously administered to mice (n = 6 each VGB/vehicle) for 12 days, after which animals were euthanized. Retina was isolated for transcriptome (RNAseq) analysis and further validation using qRT-PCR and immunohistochemistry (IHC). For 112 differentially expressed retinal genes (RNAseq), two databases (Gene Ontology; Kyoto Encyclopedia of Genes and Genomes) were used to identify genes associated with visual function. Twenty four genes were subjected to qRT-PCR validation, and five (Gb5, Bdnf, Cplx9, Crh, Sox9) revealed significant dysregulation. IHC of fixed retinas verified significant down-regulation of Gb5 in photoreceptor cells. All of these genes have been previously shown to play a role in retinal function/circuitry signaling. Minimal impact of VGB on retinal autophagic gene expression was observed. This is the first transcriptome analysis of retinal gene expression associated with VGB intake, highlighting potential novel molecular targets potentially related to VGB's well known ocular toxicity.
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Affiliation(s)
- Dana Walters
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Kara R Vogel
- Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA.
| | - Madalyn Brown
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Xutong Shi
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - Jean-Baptiste Roullet
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
| | - K Michael Gibson
- Department of Pharmacotherapy, Washington State University College of Pharmacy and Pharmaceutical Sciences, Spokane, WA, USA.
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Walters DC, Jansen EEW, Ainslie GR, Salomons GS, Brown MN, Schmidt MA, Roullet J, Gibson KM. Preclinical tissue distribution and metabolic correlations of vigabatrin, an antiepileptic drug associated with potential use-limiting visual field defects. Pharmacol Res Perspect 2019; 7:e00456. [PMID: 30631446 PMCID: PMC6321982 DOI: 10.1002/prp2.456] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 12/06/2018] [Accepted: 12/07/2018] [Indexed: 01/30/2023] Open
Abstract
Vigabatrin (VGB; (S)-(+)/(R)-(-) 4-aminohex-5-enoic acid), an antiepileptic irreversibly inactivating GABA transaminase (GABA-T), manifests use-limiting ocular toxicity. Hypothesizing that the active S enantiomer of VGB would preferentially accumulate in eye and visual cortex (VC) as one potential mechanism for ocular toxicity, we infused racemic VGB into mice via subcutaneous minipump at 35, 70, and 140 mg/kg/d (n = 6-8 animals/dose) for 12 days. VGB enantiomers, total GABA and β-alanine (BALA), 4-guanidinobutyrate (4-GBA), and creatine were quantified by mass spectrometry in eye, brain, liver, prefrontal cortex (PFC), and VC. Plasma VGB concentrations increased linearly by dose (3 ± 0.76 (35 mg/kg/d); 15.1 ± 1.4 (70 mg/kg/d); 34.6 ± 3.2 μmol/L (140 mg/kg/d); mean ± SEM) with an S/R ratio of 0.74 ± 0.02 (n = 14). Steady state S/R ratios (35, 70 mg/kg/d doses) were highest in eye (5.5 ± 0.2; P < 0.0001), followed by VC (3.9 ± 0.4), PFC (3.6 ± 0.3), liver (2.9 ± 0.1), and brain (1.5 ± 0.1; n = 13-14 each). Total VGB content of eye exceeded that of brain, PFC and VC at all doses. High-dose VGB diminished endogenous metabolite production, especially in PFC and VC. GABA significantly increased in all tissues (all doses) except brain; BALA increases were confined to liver and VC; and 4-GBA was prominently increased in brain, PFC and VC (and eye at high dose). Linear correlations between enantiomers and GABA were observed in all tissues, but only in PFC/VC for BALA, 4-GBA, and creatine. Preferential accumulation of the VGB S isomer in eye and VC may provide new insight into VGB ocular toxicity.
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Affiliation(s)
- Dana C. Walters
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
| | - Erwin E. W. Jansen
- Metabolic LaboratoryDepartment of Clinical ChemistryAmsterdam University Medical CenterAmsterdamThe Netherlands
| | - Garrett R. Ainslie
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
| | - Gajja S. Salomons
- Metabolic LaboratoryDepartment of Clinical ChemistryAmsterdam University Medical CenterAmsterdamThe Netherlands
| | - Madalyn N. Brown
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
| | - Michelle A. Schmidt
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
| | - Jean‐Baptiste Roullet
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
| | - K. M. Gibson
- Department of PharmacotherapyCollege of Pharmacy and Pharmaceutical SciencesWashington State UniversitySpokaneWashington
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Detecting Retinal Vigabatrin Toxicity in Patients with Partial Symptomatic or Cryptogenic Epilepsy. Eur J Ophthalmol 2018; 20:763-9. [DOI: 10.1177/112067211002000419] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Purpose. Detecting retinal vigabatrin toxicity in patients with partial symptomatic or cryptogenic epilepsy can be challenging because of preexisting visual field defects secondary to a structural abnormality in the brain or lack of collaboration. The aim of this study was to measure the retinal nerve fiber layer thickness (RNFLT) with optic coherence tomography (OCT), as well as contrast sensitivity, color vision, and perimetry, in patients with partial symptomatic or cryptogenic epilepsy on vigabatrin, and to determine the efficacy of these tests as markers of vigabatrin-related retinal damage in these subgroups of epileptic patients. Methods. The study involved 38 patients with either partial symptomatic or cryptogenic epilepsy and 16 healthy individuals comprising the control group. At the time of the study, 14 of the patients were using vigabatrin, 10 were receiving sodium valproate monotherapy, and 14 were on carbamazepine monotherapy. All the participants underwent RNFLT imaging with OCT, contrast sensitivity, color discrimination assessment, and perimetry. Results. The average 360° RNFLT of the vigabatrin group was significantly lower when compared to the other groups. The average RNFLT of all quadrants except the temporal one in the vigabatrin group was also significantly reduced. There was no difference in the mean deviation, contrast sensitivity, and color discrimination between the study groups, but they were all significantly lower than the control group. Conclusions. RNFLT measurement with OCT can efficiently identify vigabatrin toxicity in patients with partial symptomatic and cryptogenic epilepsy. Perimetry, contrast sensitivity, and color discrimination assessment might be inconclusive in these particular subgroups of epileptic patients.
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Tuğcu B, Bitnel MK, Kaya FS, Güveli BT, Ataklı D. Evaluation of inner retinal layers with optic coherence tomography in vigabatrin-exposed patients. Neurol Sci 2017; 38:1423-1427. [PMID: 28508989 DOI: 10.1007/s10072-017-2971-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 04/19/2017] [Indexed: 11/24/2022]
Abstract
In order to reveal the underlying retinal pathology leading to dysfunction in vigabatrin-exposed patients, we aimed to evaluate the inner retinal layers encompassing ganglion cell complex (GCC) layer and inner plexiform layer with new generation optic coherence tomography (OCT). Fourteen patients with epilepsy and exposure to vigabatrin and 12 clinically normal individuals, constituting the control group, were included. Retinal images were obtained using spectral-domain OCT (Optovue RTVue Fourier domain). Nasal and superior quadrants of retinal nerve fiber layer (RNFL) were found to be significantly lower in the patient group compared to the controls (p < 0.01). No significant difference was shown in the thickness of GCC layer (p > 0.05). Foveal thickness was significantly higher in the patient group (p: 0.006), but no significant difference was found in perifoveal and parafoveal regions between groups (p > 0.05). The thickness of RNFL was found to be lower in vigabatrin-exposed patients without any reduction in GCC layer in the macular region. However, foveal thickness was found to be significantly higher compared to perifoveal and parafoveal macular regions in vigabatrin-exposed patients. In conclusion, OCT revealed reduced thickness of RNFL without any reduction in ganglion cell layer in our study. The objective quantitative assessment of OCT is a practical noninvasive method and it can have role in future monitoring of these patients.
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Affiliation(s)
- Betül Tuğcu
- Department of Ophthalmology, Bezmialem University Medical Faculty, İstanbul, Turkey
| | - Mesrure Köseoğlu Bitnel
- Department of Neurology, Bakirkoy Research and Training Hospital for Psychiatry, Neurology, Neurosurgery, Bakırköy, 34147, Istanbul, Turkey
| | - Fatma Selin Kaya
- Department of Eye Clinic, Bakırköy Dr. Sadi Konuk Research and Training Hospital, İstanbul, Turkey
| | - Betül Tekin Güveli
- Department of Neurology, Bakirkoy Research and Training Hospital for Psychiatry, Neurology, Neurosurgery, Bakırköy, 34147, Istanbul, Turkey.
| | - Dilek Ataklı
- Department of Neurology, Bakirkoy Research and Training Hospital for Psychiatry, Neurology, Neurosurgery, Bakırköy, 34147, Istanbul, Turkey
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Nowomiejska K, Jedrych M, Brzozowska A, Rejdak K, Zarnowski T, Koss MJ, Ksiazek K, Ksiazek P, Maciejewski R, Juenemann AG, Schiefer U, Rejdak R. Relationship between the area of isopters and Vigabatrin dosage during two years of observation. BMC Ophthalmol 2014; 14:56. [PMID: 24885864 PMCID: PMC4013800 DOI: 10.1186/1471-2415-14-56] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 03/03/2014] [Indexed: 11/10/2022] Open
Abstract
Background The aim of the study was to evaluate the relationship between the area of isopters obtained using semi-automated kinetic perimetry (SKP) and Vigabatrin dosage in epilepsy patients with pretreatment baseline examination during 2-years of the follow-up. Methods 29 epilepsy patients were included into the study, but 15 individuals were excluded due to cognitive impairment, intracranial pathologies or eye diseases. Finally, 14 patients were examined with SKP before VGB treatment and after 6, 12, 18, and 24 months. Reaction time (RT)-corrected areas of three isopters (III4e, I4e and I2e) were measured for each of five examinations and compared intra-individually during 2-years period. Additionally, six epilepsy patients on other antiepileptic drugs were examined five times with SKP as a control. Results There was a significant decrease of I2e, I4e and III4e isopters’ area during the follow-up of two years. Correlation was found between the I2e isopter’s area and both cumulative dose and mean daily dose of VGB. With increasing RT, there was decreasing of all isopters’ area in patients receiving VGB. In epilepsy patients who were not receiving VGB, there were no significance differences in isopters’ area during follow-up. Conclusion There was attenuation of area of III4e, I4e and I2e isopters obtained with SKP during a period of 2 years. RT, the cumulative dose and the mean daily dose of VGB influenced isopters' area obtained with SKP.
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Affiliation(s)
- Katarzyna Nowomiejska
- Department of General Ophthalmology, Medical University, ul, Chmielna 1, 20-079 Lublin, Poland.
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Barrett D, Yang J, Sujirakul T, Tsang SH. Vigabatrin Retinal Toxicity First Detected with Electroretinographic Changes: A Case Report. ACTA ACUST UNITED AC 2014; 5. [PMID: 26295007 DOI: 10.4172/2155-9570.1000363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Vigabatrin is an effective antiepileptic drug (AED) typically used in the treatment of refractory partial seizures and infantile spasms. Its use, however, is limited due to the concern of retinal toxicity and subsequent visual field defects. Herewith in we describe a case of vigabatrin toxicity that illustrates electroretinographic (ERG) changes occur before imaging and visual field deterioration. Decrease in maximal ERG b: a ratio was observed before thinning of the retinal nerve fiber layer (RNFL) on optical coherence tomography (OCT).
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Affiliation(s)
- Dianne Barrett
- College of Physicians & Surgeons, Columbia University, New York, NY 10032, USA
| | - Jin Yang
- Edward S. Harkness Eye Institute, Columbia University, New York, NY 10032, USA
| | - Tharikarn Sujirakul
- Edward S. Harkness Eye Institute, Columbia University, New York, NY 10032, USA
| | - Stephen H Tsang
- Edward S. Harkness Eye Institute, Columbia University, New York, NY 10032, USA ; Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology & Cell Biology, Columbia University, New York, NY 10032, USA ; New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
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Visual field and ocular safety during short-term vigabatrin treatment in cocaine abusers. Am J Ophthalmol 2012; 154:326-332.e2. [PMID: 22704138 DOI: 10.1016/j.ajo.2012.02.026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 02/17/2012] [Accepted: 02/21/2012] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the ocular safety of short-term vigabatrin treatment of cocaine abuse. DESIGN Multicenter, prospective, randomized, placebo-controlled, double-masked, parallel assignment study. METHODS Cocaine addicts were randomized to receive vigabatrin 3000 mg/day, cumulative dose 218 g (n = 92), or placebo (n = 94) for 12 weeks. Subjects underwent examination of visual acuity (ETDRS) and peripheral visual field (PVF) by Humphrey Field Analyzer (HFA) 60-4 program before and after treatment. Reliable PVF tests (fixation loss, false positive, and false negative <33%) for 103 subjects were included for the analysis. The threshold visual sensitivity (TVS) was analyzed by points, rings and zones. Main outcome measures included visual acuity decrease by 15 letters and/or significant PVF alteration, defined as 5 or more visual field location points having greater than or equal to 15 dB reduction in TVS or decline (≥33% loss) in posttreatment TVS for 1 or more rings. RESULTS Visual acuity decrease was detected in 1 eye of a subject receiving placebo and in none receiving vigabatrin. Posttreatment reduction in TVS more than 15 dB in 5 or more adjacent visual field location points combined with reduction in TVS greater than 33% in 1 or more of the rings was detected in 2 of 54 subjects (3.7%) from the vigabatrin group and in 1 of 49 subjects (2%) from the placebo group (P = .9, NS). None of the PVF changes were bilateral or concentric. CONCLUSIONS Short-term use of vigabatrin did not cause a decrease in visual acuity or significant peripheral visual field changes in cocaine abusers.
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Moskowitz A, Hansen RM, Eklund SE, Fulton AB. Electroretinographic (ERG) responses in pediatric patients using vigabatrin. Doc Ophthalmol 2012; 124:197-209. [PMID: 22426576 DOI: 10.1007/s10633-012-9320-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 03/02/2012] [Indexed: 11/30/2022]
Abstract
The antiepileptic drug vigabatrin is known to cause retinal and visual dysfunction, particularly visual field defects, in some patients. Electroretinography (ERG) is used in an attempt to identify adverse effects of vigabatrin (VGB) in patients who are not candidates for conventional perimetry. We report data from 114 pediatric patients taking VGB referred for clinical evaluation; median age at test was 22.9 (2.4 to 266.1) months, and median duration of VGB use was 9.7 (0.3 to 140.7) months. Twenty-seven of them were tested longitudinally (3 to 12 ERG tests). ERG responses to full-field stimuli were recorded in scotopic and photopic conditions, and results were compared to responses from healthy control subjects. We found that abnormalities of photoreceptor and post-receptor ERG responses are frequent in these young patients. The most frequently abnormal scotopic parameter was post-receptor sensitivity, log σ, derived from the b-wave stimulus-response function; the most frequently abnormal photopic parameter was the implicit time of the OFF response (d-wave) to a long (150 ms) flash. Abnormal 30-Hz flicker response amplitude, previously reported to be a predictor of visual field loss, occurred infrequently. For the group as a whole, none of the ERG parameters changed significantly with increasing duration of VGB use. Four of the 27 patients tested longitudinally showed systematic worsening of log σ with duration of VGB use. In a subset of patients who underwent perimetry (N = 39), there was no significant association of any ERG parameter with visual field defects. We cannot determine whether the ERG abnormalities we found were due solely to the effects of VGB. We caution against over-reliance on the ERG to monitor pediatric patients for VGB toxicity and recommend further development of a reliable test of peripheral vision to supplant ERG testing.
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Affiliation(s)
- Anne Moskowitz
- Department of Ophthalmology, Children's Hospital and Harvard Medical School, Boston, MA 02115, USA.
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Anti-relapse medications: preclinical models for drug addiction treatment. Pharmacol Ther 2009; 124:235-47. [PMID: 19683019 DOI: 10.1016/j.pharmthera.2009.06.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 06/12/2009] [Indexed: 12/15/2022]
Abstract
Addiction is a chronic relapsing brain disease and treatment of relapse to drug-seeking is considered the most challenging part of treating addictive disorders. Relapse can be modeled in laboratory animals using reinstatement paradigms, whereby behavioral responding for a drug is extinguished and then reinstated by different trigger factors, such as environmental cues or stress. In this review, we first describe currently used animal models of relapse, different relapse triggering factors, and the validity of this model to assess relapse in humans. We further summarize the growing body of pharmacological interventions that have shown some promise in treating relapse to psychostimulant addiction. Moreover, we present an overview on the drugs tested in cocaine or methamphetamine addicts and examine the overlap of existing preclinical and clinical data. Finally, based on recent advances in our understanding of the neurobiology of relapse and published preclinical data, we highlight the most promising areas for future anti-relapse medication development.
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Current awareness: Pharmacoepidemiology and drug safety. Pharmacoepidemiol Drug Saf 2009. [DOI: 10.1002/pds.1645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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