1
|
Potschka H, Fischer A, Löscher W, Volk HA. Pathophysiology of drug-resistant canine epilepsy. Vet J 2023; 296-297:105990. [PMID: 37150317 DOI: 10.1016/j.tvjl.2023.105990] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 05/04/2023] [Accepted: 05/04/2023] [Indexed: 05/09/2023]
Abstract
Drug resistance continues to be a major clinical problem in the therapeutic management of canine epilepsies with substantial implications for quality of life and survival times. Experimental and clinical data from human medicine provided evidence for relevant contributions of intrinsic severity of the disease as well as alterations in pharmacokinetics and -dynamics to failure to respond to antiseizure medications. In addition, several modulatory factors have been identified that can be associated with the level of therapeutic responses. Among others, the list of potential modulatory factors comprises genetic and epigenetic factors, inflammatory mediators, and metabolites. Regarding data from dogs, there are obvious gaps in knowledge when it comes to our understanding of the clinical patterns and the mechanisms of drug-resistant canine epilepsy. So far, seizure density and the occurrence of cluster seizures have been linked with a poor response to antiseizure medications. Moreover, evidence exists that the genetic background and alterations in epigenetic mechanisms might influence the efficacy of antiseizure medications in dogs with epilepsy. Further molecular, cellular, and network alterations that may affect intrinsic severity, pharmacokinetics, and -dynamics have been reported. However, the association with drug responsiveness has not yet been studied in detail. In summary, there is an urgent need to strengthen clinical and experimental research efforts exploring the mechanisms of resistance as well as their association with different etiologies, epilepsy types, and clinical courses.
Collapse
Affiliation(s)
- Heidrun Potschka
- Institute of Pharmacology, Toxicology, and Pharmacy, Ludwig-Maximilians-University, Munich, Germany.
| | - Andrea Fischer
- Clinic of Small Animal Medicine, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University, Munich, Germany
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology, and Pharmacy, University of Veterinary Medicine, Hannover, Germany; Center for Systems Neuroscience, Hannover, Germany
| | - Holger A Volk
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| |
Collapse
|
2
|
Yadav K, Batra P, Bhaskar V, Aggarwal A, Banerjee BD, Kumar H, Sharma T. Genetic Expression of CYP2B6 Gene in Phenobarbitone Responder and Non-responder Neonates. Indian Pediatr 2023. [DOI: 10.1007/s13312-023-2843-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
|
3
|
Abstract
Epilepsy is a common neurological disease in both humans and domestic dogs, making dogs an ideal translational model of epilepsy. In both species, epilepsy is a complex brain disease characterized by an enduring predisposition to generate spontaneous recurrent epileptic seizures. Furthermore, as in humans, status epilepticus is one of the more common neurological emergencies in dogs with epilepsy. In both species, epilepsy is not a single disease but a group of disorders characterized by a broad array of clinical signs, age of onset, and underlying causes. Brain imaging suggests that the limbic system, including the hippocampus and cingulate gyrus, is often affected in canine epilepsy, which could explain the high incidence of comorbid behavioral problems such as anxiety and cognitive alterations. Resistance to antiseizure medications is a significant problem in both canine and human epilepsy, so dogs can be used to study mechanisms of drug resistance and develop novel therapeutic strategies to benefit both species. Importantly, dogs are large enough to accommodate intracranial EEG and responsive neurostimulation devices designed for humans. Studies in epileptic dogs with such devices have reported ictal and interictal events that are remarkably similar to those occurring in human epilepsy. Continuous (24/7) EEG recordings in a select group of epileptic dogs for >1 year have provided a rich dataset of unprecedented length for studying seizure periodicities and developing new methods for seizure forecasting. The data presented in this review substantiate that canine epilepsy is an excellent translational model for several facets of epilepsy research. Furthermore, several techniques of inducing seizures in laboratory dogs are discussed as related to therapeutic advances. Importantly, the development of vagus nerve stimulation as a novel therapy for drug-resistant epilepsy in people was based on a series of studies in dogs with induced seizures. Dogs with naturally occurring or induced seizures provide excellent large-animal models to bridge the translational gap between rodents and humans in the development of novel therapies. Furthermore, because the dog is not only a preclinical species for human medicine but also a potential patient and pet, research on this species serves both veterinary and human medicine.
Collapse
Affiliation(s)
- Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine, Hannover, Germany
- Center for Systems Neuroscience, Hannover, Germany
| |
Collapse
|
4
|
Menchetti M, Perillo R, Bianchi E, Matiasek K, Rosati M. Transient relapsing neuromyopathy during potassium bromide therapy in a dog. VETERINARY RECORD CASE REPORTS 2021. [DOI: 10.1002/vrc2.157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Marika Menchetti
- Neurology and Neurosurgery Division San Marco Veterinary Clinic Padua Italy
| | - Raffaella Perillo
- Neurology and Neurosurgery Division San Marco Veterinary Clinic Padua Italy
| | - Ezio Bianchi
- Department of Veterinary Science, University of Parma Parma Italy
| | - Kaspar Matiasek
- Section of Clinical & Comparative Neuropathology, Ludwig‐Maximilians‐Universität Munich Germany
| | - Marco Rosati
- Section of Clinical & Comparative Neuropathology, Ludwig‐Maximilians‐Universität Munich Germany
| |
Collapse
|
5
|
Gagliardo T, Gandini G, Gallucci A, Menchetti M, Bianchi E, Turba ME, Cauduro A, Corlazzoli DS, Gianni S, Baroni M, Bernardini M, Gentilini F. ABCB1 c.-6-180T>G polymorphism and clinical risk factors in a multi-breed cohort of dogs with refractory idiopathic epilepsy. Vet J 2019; 253:105378. [PMID: 31685133 DOI: 10.1016/j.tvjl.2019.105378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 08/19/2019] [Accepted: 09/10/2019] [Indexed: 10/26/2022]
Abstract
Epilepsy is the most common chronic neurological disorder in dogs. Approximately 20-30% of dogs do not achieve satisfactory seizure control with two or more anti-epileptic drugs at appropriate dosages. This condition, defined as refractory epilepsy, is a multifactorial condition involving both acquired and genetic factors. The P glycoprotein might play and important role in the pathophysiological mechanism and it is encoded by the ABCB1 gene. An association between a single nucleotide variation of the ABCB1 gene (c.-6-180T>G) and phenobarbital resistance has previously been reported in a Border collie population with idiopathic epilepsy. To date, the presence and relevance of this polymorphism has not been assessed in other breeds. A multicentre retrospective, case-control study was conducted to investigate associations between ABCB1 c.-6-180T>G, clinical variables, and refractoriness in a multi-breed population of dogs with refractory idiopathic epilepsy. A secondary aim was to evaluate the possible involvement of the ABCB1 c.-6-180T>G single nucleotide variation this population. Fifty-two refractory and 50 responsive dogs with idiopathic epilepsy were enrolled. Of these, 45 refractory and 50 responsive (control) dogs were genotyped. The G allele was found in several breeds, but there was no evidence of association with refractoriness (P=0.69). The uncertain role of the c.-6-180T>G variation was further suggested by an association between the T/T genotype with both refractoriness and responsiveness in different breeds. Furthermore, high seizure density (cluster seizure) was the main clinical risk factor for refractory idiopathic epilepsy (P=0.003).
Collapse
Affiliation(s)
- T Gagliardo
- Department of Veterinary Medical Sciences, University of Bologna, 50 via Tolara di sopra, Ozzano dell'Emilia, BO 40064, Italy.
| | - G Gandini
- Department of Veterinary Medical Sciences, University of Bologna, 50 via Tolara di sopra, Ozzano dell'Emilia, BO 40064, Italy
| | - A Gallucci
- Department of Veterinary Medical Sciences, University of Bologna, 50 via Tolara di sopra, Ozzano dell'Emilia, BO 40064, Italy
| | - M Menchetti
- Department of Veterinary Medical Sciences, University of Bologna, 50 via Tolara di sopra, Ozzano dell'Emilia, BO 40064, Italy
| | - E Bianchi
- Department of Veterinary Medical Sciences, University of Parma, 80 via Tiglio, Parma, PR 43100, Italy
| | - M E Turba
- Genefast, Bologna, 17/d via Castelfranco, Valsamoggia, BO 40053, Italy
| | - A Cauduro
- Neurovet Professional Association, 29 via Maestri del lavoro, Legnano, MI 20025, Italy
| | - D S Corlazzoli
- Roma Sud Veterinary Clinic, 24 via Pilade Mazza, Rome, RM 00173, Italy
| | - S Gianni
- Gran Sasso Veterinary Clinic, 26 via Donatello, Milan, MI 20131, Italy
| | - M Baroni
- Valdinievole Veterinary Hospital, 123 via Nigra Costantino, Monsummano Terme, PT 51015, Italy
| | - M Bernardini
- Portoni Rossi Veterinary Hospital, 57/a via Roma, Zola Predosa, BO 40069, Italy
| | - F Gentilini
- Department of Veterinary Medical Sciences, University of Bologna, 50 via Tolara di sopra, Ozzano dell'Emilia, BO 40064, Italy
| |
Collapse
|
6
|
Devinsky O, Boesch JM, Cerda-Gonzalez S, Coffey B, Davis K, Friedman D, Hainline B, Houpt K, Lieberman D, Perry P, Prüss H, Samuels MA, Small GW, Volk H, Summerfield A, Vite C, Wisniewski T, Natterson-Horowitz B. A cross-species approach to disorders affecting brain and behaviour. Nat Rev Neurol 2019; 14:677-686. [PMID: 30287906 DOI: 10.1038/s41582-018-0074-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Structural and functional elements of biological systems are highly conserved across vertebrates. Many neurological and psychiatric conditions affect both humans and animals. A cross-species approach to the study of brain and behaviour can advance our understanding of human disorders via the identification of unrecognized natural models of spontaneous disorders, thus revealing novel factors that increase vulnerability or resilience, and via the assessment of potential therapies. Moreover, diagnostic and therapeutic advances in human neurology and psychiatry can often be adapted for veterinary patients. However, clinical and research collaborations between physicians and veterinarians remain limited, leaving this wealth of comparative information largely untapped. Here, we review pain, cognitive decline syndromes, epilepsy, anxiety and compulsions, autoimmune and infectious encephalitides and mismatch disorders across a range of animal species, looking for novel insights with translational potential. This comparative perspective can help generate novel hypotheses, expand and improve clinical trials and identify natural animal models of disease resistance and vulnerability.
Collapse
Affiliation(s)
- Orrin Devinsky
- Department of Neurology, New York University (NYU) Langone Medical Center and NYU School of Medicine, New York, NY, USA.
| | - Jordyn M Boesch
- College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | | | - Barbara Coffey
- Department of Child and Adolescent Psychiatry, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Kathryn Davis
- Department of Neurology, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Daniel Friedman
- Department of Neurology, New York University (NYU) Langone Medical Center and NYU School of Medicine, New York, NY, USA
| | - Brian Hainline
- Department of Neurology, New York University (NYU) Langone Medical Center and NYU School of Medicine, New York, NY, USA
| | - Katherine Houpt
- College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Daniel Lieberman
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Pamela Perry
- College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Harald Prüss
- Department of Neurology with Experimental Neurology, Charité University Medicine Berlin, Berlin, Germany, and German Center for Neurodegenerative Diseases (DZNE), Berlin, Germany
| | | | - Gary W Small
- University of California-Los Angeles (UCLA) Brain Research Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Holger Volk
- Veterinary Neurology and Neurosurgery, The Royal Veterinary College, University of London, London, UK
| | - Artur Summerfield
- Institute of Virology and Immunology and Department of Infectious Diseases and Pathobiology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Charles Vite
- School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Thomas Wisniewski
- Department of Neurology, New York University (NYU) Langone Medical Center and NYU School of Medicine, New York, NY, USA
| | - Barbara Natterson-Horowitz
- Department of Ecology and Evolutionary Biology, Division of Cardiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| |
Collapse
|
7
|
Lee JJ, Lin HY, Chen CA, Lin CS, Wang LC. Development of an oligonucleotide microarray for simultaneous detection of two canine MDR1 genotypes and association between genotypes and chemotherapy side effects. J Vet Sci 2019; 20:27-33. [PMID: 30481983 PMCID: PMC6351760 DOI: 10.4142/jvs.2019.20.1.27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/30/2018] [Accepted: 11/06/2018] [Indexed: 12/12/2022] Open
Abstract
Canine MDR1 gene mutations produce translated P-glycoprotein, an active drug efflux transporter, resulting in dysfunction or over-expression. The 4-base deletion at exon 4 of MDR1 at nucleotide position 230 (nt230[del4]) in exon 4 makes P-glycoprotein lose function, leading to drug accumulation and toxicity. The G allele of the c.-6-180T>G variation in intron 1 of MDR1 (single nucleotide polymorphism [SNP] 180) causes P-glycoprotein over-expression, making epileptic dogs resistant to phenobarbital treatment. Both of these mutations are reported to be common in collies. This study develops a more efficient method to detect these two mutations simultaneously, and clarifies the genotype association with the side effects of chemotherapy. Genotype distribution in Taiwan was also investigated. An oligonucleotide microarray was successfully developed for the detection of both genotypes and was applied to clinical samples. No 4-base deletion mutant allele was detected in dogs in Taiwan. However, the G allele variation of SNP 180 was spread across all dog breeds, not only in collies. The chemotherapy adverse effect percentages of the SNP 180 T/T, T/G, and G/G genotypes were 16.7%, 6.3%, and 0%, respectively. This study describes an efficient way for MDR1 gene mutation detection, clarifying genotype distribution, and the association with chemotherapy.
Collapse
Affiliation(s)
- Jih-Jong Lee
- School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Han-You Lin
- School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Chun-An Chen
- School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Chen-Si Lin
- School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Lih-Chiann Wang
- School of Veterinary Medicine, National Taiwan University, Taipei 10617, Taiwan
| |
Collapse
|
8
|
Bhatti SFM, De Risio L, Muñana K, Penderis J, Stein VM, Tipold A, Berendt M, Farquhar RG, Fischer A, Long S, Löscher W, Mandigers PJJ, Matiasek K, Pakozdy A, Patterson EE, Platt S, Podell M, Potschka H, Rusbridge C, Volk HA. International Veterinary Epilepsy Task Force consensus proposal: medical treatment of canine epilepsy in Europe. BMC Vet Res 2015; 11:176. [PMID: 26316233 PMCID: PMC4552371 DOI: 10.1186/s12917-015-0464-z] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/29/2015] [Indexed: 12/14/2022] Open
Abstract
In Europe, the number of antiepileptic drugs (AEDs) licensed for dogs has grown considerably over the last years. Nevertheless, the same questions remain, which include, 1) when to start treatment, 2) which drug is best used initially, 3) which adjunctive AED can be advised if treatment with the initial drug is unsatisfactory, and 4) when treatment changes should be considered. In this consensus proposal, an overview is given on the aim of AED treatment, when to start long-term treatment in canine epilepsy and which veterinary AEDs are currently in use for dogs. The consensus proposal for drug treatment protocols, 1) is based on current published evidence-based literature, 2) considers the current legal framework of the cascade regulation for the prescription of veterinary drugs in Europe, and 3) reflects the authors' experience. With this paper it is aimed to provide a consensus for the management of canine idiopathic epilepsy. Furthermore, for the management of structural epilepsy AEDs are inevitable in addition to treating the underlying cause, if possible.
Collapse
Affiliation(s)
- Sofie F M Bhatti
- Department of Small Animal Medicine and Clinical Biology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, Merelbeke, 9820, Belgium.
| | - Luisa De Risio
- Animal Health Trust, Lanwades Park, Kentford, Newmarket, CB8 7UU, Suffolk, United Kingdom.
| | - Karen Muñana
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 1052 William Moore Drive, Raleigh, NC, 27607, USA.
| | - Jacques Penderis
- Vet Extra Neurology, Broadleys Veterinary Hospital, Craig Leith Road, Stirling, FK7 7LE, Stirlingshire, United Kingdom.
| | - Veronika M Stein
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg 9, 30559, Hannover, Germany.
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine Hannover, Bünteweg 9, 30559, Hannover, Germany.
| | - Mette Berendt
- Department of Veterinary and Clinical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg C, Denmark.
| | - Robyn G Farquhar
- Fernside Veterinary Centre, 205 Shenley Road, Borehamwood, SG9 0TH, Hertfordshire, United Kingdom.
| | - Andrea Fischer
- Clinical Veterinary Medicine, Ludwig-Maximillians-University, Veterinärstr. 13, 80539, Munich, Germany.
| | - Sam Long
- University of Melbourne, 250 Princes Highway, Weibee, 3015, VIC, Australia.
| | - Wolfgang Löscher
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Bünteweg 17, 30559, Hannover, Germany.
| | - Paul J J Mandigers
- Department of Clinical Sciences of Companion Animals, Utrecht University, Yalelaan 108, 3583 CM, Utrecht, The Netherlands.
| | - Kaspar Matiasek
- Section of Clinical & Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-University, Veterinärstr. 13, 80539, Munich, Germany.
| | - Akos Pakozdy
- Clinical Unit of Internal Medicine Small Animals, University of Veterinary Medicine, Veterinärplatz 1, 1210, Vienna, Austria.
| | - Edward E Patterson
- University of Minnesota College of Veterinary Medicine, D426 Veterinary Medical Center, 1352 Boyd Avenue, St. Paul, MN, 55108, USA.
| | - Simon Platt
- College of Veterinary Medicine, University of Georgia, 501 DW Brooks Drive, Athens, GA, 30602, USA.
| | - Michael Podell
- Chicago Veterinary Neurology and Neurosurgery, 3123 N. Clybourn Avenue, Chicago, IL, 60618, USA.
| | - Heidrun Potschka
- Department of Pharmacology, Toxicology and Pharmacy, Ludwig-Maximillians-University, Königinstr. 16, 80539, Munich, Germany.
| | - Clare Rusbridge
- Fitzpatrick Referrals, Halfway Lane, Eashing, Godalming, GU7 2QQ, Surrey, United Kingdom.
- School of Veterinary Medicine, Faculty of Health & Medical Sciences, University of Surrey, Guildford, GU2 7TE, Surrey, United Kingdom.
| | - Holger A Volk
- Department of Clinical Science and Services, Royal Veterinary College, Hatfield, AL9 7TA, Hertfordshire, UK.
| |
Collapse
|
9
|
International Veterinary Epilepsy Task Force's current understanding of idiopathic epilepsy of genetic or suspected genetic origin in purebred dogs. BMC Vet Res 2015; 11:175. [PMID: 26316206 PMCID: PMC4552344 DOI: 10.1186/s12917-015-0463-0] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 06/29/2015] [Indexed: 12/20/2022] Open
Abstract
Canine idiopathic epilepsy is a common neurological disease affecting both purebred and crossbred dogs. Various breed-specific cohort, epidemiological and genetic studies have been conducted to date, which all improved our knowledge and general understanding of canine idiopathic epilepsy, and in particular our knowledge of those breeds studied. However, these studies also frequently revealed differences between the investigated breeds with respect to clinical features, inheritance and prevalence rates. Awareness and observation of breed-specific differences is important for successful management of the dog with epilepsy in everyday clinical practice and furthermore may promote canine epilepsy research. The following manuscript reviews the evidence available for breeds which have been identified as being predisposed to idiopathic epilepsy with a proven or suspected genetic background, and highlights different breed specific clinical features (e.g. age at onset, sex, seizure type), treatment response, prevalence rates and proposed inheritance reported in the literature. In addition, certain breed-specific diseases that may act as potential differentials for idiopathic epilepsy are highlighted.
Collapse
|
10
|
Gagliardi R, Llambí S, Arruga MV. SNP genetic polymorphisms of MDR-1, CYP1A2 and CYPB11 genes in four canine breeds upon toxicological evaluation. J Vet Sci 2015; 16:273-80. [PMID: 25797294 PMCID: PMC4588012 DOI: 10.4142/jvs.2015.16.3.273] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Revised: 02/19/2015] [Accepted: 03/07/2015] [Indexed: 11/20/2022] Open
Abstract
The fields of pharmacogenetics and pharmacogenomics have become increasingly promising regarding the clinical application of genetic data to aid in prevention of adverse reactions. Specific screening tests can predict which animals express modified proteins or genetic sequences responsible for adverse effects associated with a drug. Among the genetic variations that have been investigated in dogs, the multidrug resistance gene (MDR) is the best studied. However, other genes such as CYP1A2 and CYP2B11 control the protein syntheses involved in the metabolism of many drugs. In the present study, the MDR-1, CYP1A2 and CYP2B11 genes were examined to identify SNP polymorphisms associated with these genes in the following four canine breeds: Uruguayan Cimarron, Border Collie, Labrador Retriever and German Shepherd. The results revealed that several SNPs of the CYP1A2 and CYP2B11 genes are potential targets for drug sensitivity investigations.
Collapse
Affiliation(s)
- Rosa Gagliardi
- Genetic Area, Faculty of Veterinary, University of La República, Montevideo, C.P. 11600, Uruguay
| | | | | |
Collapse
|
11
|
Affiliation(s)
- Jacques Penderis
- Vet‐Extra Neurology, Broadleys Veterinary HospitalCraig Leith RoadStirlingFK7 7LEUK
| |
Collapse
|
12
|
Affiliation(s)
- Clare Rusbridge
- Fitzpatrick ReferralsHalfway LaneEashing, GodalmingSurreyGU7 2QQUK
- School of Veterinary MedicineUniversity of SurreyGuildfordSurreyGU2 7XHUK
| |
Collapse
|
13
|
Ekenstedt KJ, Oberbauer AM. Inherited epilepsy in dogs. Top Companion Anim Med 2014; 28:51-8. [PMID: 24070682 DOI: 10.1053/j.tcam.2013.07.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2013] [Accepted: 07/01/2013] [Indexed: 12/15/2022]
Abstract
Epilepsy is the most common neurologic disease in dogs and many forms are considered to have a genetic basis. In contrast, some seizure disorders are also heritable, but are not technically defined as epilepsy. Investigation of true canine epilepsies has uncovered genetic associations in some cases, however, many remain unexplained. Gene mutations have been described for 2 forms of canine epilepsy: primary epilepsy (PE) and progressive myoclonic epilepsies. To date, 9 genes have been described to underlie progressive myoclonic epilepsies in several dog breeds. Investigations into genetic PE have been less successful, with only 1 causative gene described. Genetic testing as an aid to diagnosis, prognosis, and breeding decisions is available for these 10 forms. Additional studies utilizing genome-wide tools have identified PE loci of interest; however, specific genetic tests are not yet developed. Many studies of dog breeds with PE have failed to identify genes or loci of interest, suggesting that, similar to what is seen in many human genetic epilepsies, inheritance is likely complex, involving several or many genes, and reflective of environmental interactions. An individual dog's response to therapeutic intervention for epilepsy may also be genetically complex. Although the field of inherited epilepsy has faced challenges, particularly with PE, newer technologies contribute to further advances.
Collapse
Affiliation(s)
- Kari J Ekenstedt
- Department of Animal and Food Science, College of Agriculture, Food, and Environmental Sciences, University of Wisconsin - River Falls, River Falls, WI, USA.
| | | |
Collapse
|
14
|
High frequency of a single nucleotide substitution (c.-6-180T>G) of the canine MDR1/ABCB1 gene associated with phenobarbital-resistant idiopathic epilepsy in Border Collie dogs. DISEASE MARKERS 2013; 35:669-72. [PMID: 24302812 PMCID: PMC3834651 DOI: 10.1155/2013/695918] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 10/11/2013] [Accepted: 10/24/2013] [Indexed: 01/28/2023]
Abstract
A single nucleotide substitution (c.-6-180T>G) associated with resistance to phenobarbital therapy has been found in the canine MDR1/ABCB1 gene in Border Collies with idiopathic epilepsy. In the present study, a PCR-restriction fragment length polymorphism assay was developed for genotyping this mutation, and a genotyping survey was carried out in a population of 472 Border Collies in Japan to determine the current allele frequency. The survey demonstrated the frequencies of the T/T wild type, T/G heterozygote, and G/G mutant homozygote to be 60.0%, 30.3%, and 9.8%, respectively, indicating that the frequency of the mutant G allele is extremely high (24.9%) in Border Collies. The results suggest that this high mutation frequency of the mutation is likely to cause a high prevalence of phenobarbital-resistant epilepsy in Border Collies.
Collapse
|
15
|
Muñana K, Nettifee-Osborne J, Bergman R, Mealey K. Association between ABCB1 Genotype and Seizure Outcome in Collies with Epilepsy. J Vet Intern Med 2012; 26:1358-64. [DOI: 10.1111/j.1939-1676.2012.01006.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2012] [Revised: 06/13/2012] [Accepted: 08/15/2012] [Indexed: 01/02/2023] Open
Affiliation(s)
- K.R. Muñana
- Department of Clinical Sciences; College of Veterinary Medicine, North Carolina State University; Raleigh; NC
| | - J.A. Nettifee-Osborne
- Department of Clinical Sciences; College of Veterinary Medicine, North Carolina State University; Raleigh; NC
| | - R.L. Bergman
- Department of Clinical Sciences; College of Veterinary Medicine, North Carolina State University; Raleigh; NC
| | - K.L. Mealey
- Department of Veterinary Clinical Sciences; College of Veterinary Medicine, Washington State University; Pullman; WA
| |
Collapse
|
16
|
Weissl J, Hülsmeyer V, Brauer C, Tipold A, Koskinen LL, Kyöstilä K, Lohi H, Sauter-Louis C, Wolf M, Fischer A. Disease progression and treatment response of idiopathic epilepsy in Australian Shepherd dogs. J Vet Intern Med 2011; 26:116-25. [PMID: 22182230 DOI: 10.1111/j.1939-1676.2011.00853.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Revised: 09/25/2011] [Accepted: 11/14/2011] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Idiopathic epilepsy (IE) in Australian Shepherds (ASs) occurs worldwide but there is a lack of description of the epilepsy syndrome in this breed. The ABCB1-1Δ mutation is more prevalent in ASs than in many other dog breeds. HYPOTHESIS Australian Shepherds suffer from a poorly controlled IE syndrome with prevailing severe courses. Seizure control and ABCB1-1Δ mutation might be related in this breed. ANIMALS Fifty ASs diagnosed with IE and 50 unaffected ASs. METHODS Predominant study design is a longitudinal cohort study. Pedigrees, medical records, seizure, and treatment data of ASs with IE were analyzed descriptively. Sex, color, and the ABCB1-1Δ genotype were compared between case and control groups and ASs with poorly or well-controlled seizures. Differences in survival times were assessed by logrank tests and Cox regression analysis. RESULTS Idiopathic epilepsy in ASs is dominated by moderate and severe clinical courses with the occurrence of cluster seizures and status epilepticus and a high seizure frequency. Poor seizure control and a high initial seizure frequency (≥10 seizure days/first 6 months) are associated with shorter survival times (P < .05). Poor seizure control, unrelated to the ABCB1(MDR1) genotype, is evident in 56% of epileptic ASs. Pedigree analysis suggests a genetic basis. CONCLUSION AND CLINICAL IMPORTANCE Frequent severe clinical courses, poor seizure control unrelated to the ABCB1(MDR1) genotype, and a young age at death compromise animal welfare and warrant further genetic studies to unravel the underlaying molecular mechanisms of IE and seizure control in the breed.
Collapse
Affiliation(s)
- J Weissl
- Clinic of Small Animal Medicine, Ludwig-Maximilians-University, Munich, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
|