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Gu J, Shao W, Liu L, Wang Y, Yang Y, Zhang Z, Wu Y, Xu Q, Gu L, Zhang Y, Shen Y, Zhao H, Zeng C, Zhang H. Challenges and future directions of SUDEP models. Lab Anim (NY) 2024:10.1038/s41684-024-01426-y. [PMID: 39187733 DOI: 10.1038/s41684-024-01426-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 08/02/2024] [Indexed: 08/28/2024]
Abstract
Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death among patients with epilepsy, causing a global public health burden. The underlying mechanisms of SUDEP remain elusive, and effective prevention or treatment strategies require further investigation. A major challenge in current SUDEP research is the lack of an ideal model that maximally mimics the human condition. Animal models are important for revealing the potential pathogenesis of SUDEP and preventing its occurrence; however, they have potential limitations due to species differences that prevent them from precisely replicating the intricate physiological and pathological processes of human disease. This Review provides a comprehensive overview of several available SUDEP animal models, highlighting their pros and cons. More importantly, we further propose the establishment of an ideal model based on brain-computer interfaces and artificial intelligence, hoping to offer new insights into potential advancements in SUDEP research. In doing so, we hope to provide valuable information for SUDEP researchers, offer new insights into the pathogenesis of SUDEP and open new avenues for the development of strategies to prevent SUDEP.
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Affiliation(s)
- JiaXuan Gu
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - WeiHui Shao
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Lu Liu
- Department of Anesthesiology, Zhejiang University School of Medicine, Hangzhou, China
| | - YuLing Wang
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yue Yang
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - ZhuoYue Zhang
- Department of Anesthesiology, Zhejiang University School of Medicine, Hangzhou, China
| | - YaXuan Wu
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Qing Xu
- Department of Anesthesiology, Zhejiang University School of Medicine, Hangzhou, China
| | - LeYuan Gu
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - YuanLi Zhang
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China
| | - Yue Shen
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Westlake University School of Medicine, Hangzhou, China
| | - HaiTing Zhao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Chang Zeng
- Health Management Center, Xiangya Hospital, Central South University, Changsha, China
| | - HongHai Zhang
- Department of Anesthesiology, the Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, China.
- Department of Anesthesiology, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Anesthesiology, Affiliated Hangzhou First People's Hospital, Westlake University School of Medicine, Hangzhou, China.
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Yu C, Deng XJ, Xu D. Gene mutations in comorbidity of epilepsy and arrhythmia. J Neurol 2023; 270:1229-1248. [PMID: 36376730 DOI: 10.1007/s00415-022-11430-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 10/14/2022] [Accepted: 10/15/2022] [Indexed: 11/16/2022]
Abstract
Epilepsy is one of the most common neurological disorders, and sudden unexpected death in epilepsy (SUDEP) is the most severe outcome of refractory epilepsy. Arrhythmia is one of the heterogeneous factors in the pathophysiological mechanism of SUDEP with a high incidence in patients with refractory epilepsy, increasing the risk of premature death. The gene co-expressed in the brain and heart is supposed to be the genetic basis between epilepsy and arrhythmia, among which the gene encoding ion channel contributes to the prevalence of "cardiocerebral channelopathy" theory. Nevertheless, this theory could only explain the molecular mechanism of comorbid arrhythmia in part of patients with epilepsy (PWE). Therefore, we summarized the mutant genes that can induce comorbidity of epilepsy and arrhythmia and the possible corresponding treatments. These variants involved the genes encoding sodium, potassium, calcium and HCN channels, as well as some non-ion channel coding genes such as CHD4, PKP2, FHF1, GNB5, and mitochondrial genes. The relationship between genotype and clinical phenotype was not simple linear. Indeed, genes co-expressed in the brain and heart could independently induce epilepsy and/or arrhythmia. Mutant genes in brain could affect cardiac rhythm through central or peripheral regulation, while in the heart it could also affect cerebral electrical activity by changing the hemodynamics or internal environment. Analysis of mutations in comorbidity of epilepsy and arrhythmia could refine and expand the theory of "cardiocerebral channelopathy" and provide new insights for risk stratification of premature death and corresponding precision therapy in PWE.
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Affiliation(s)
- Cheng Yu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, Hubei Province, China
| | - Xue-Jun Deng
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, Hubei Province, China
| | - Da Xu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, 430022, Hubei Province, China.
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Evidence for Dual Activation of IK(M) and IK(Ca) Caused by QO-58 (5-(2,6-Dichloro-5-fluoropyridin-3-yl)-3-phenyl-2-(trifluoromethyl)-1H-pyrazolol[1,5-a]pyrimidin-7-one). Int J Mol Sci 2022; 23:ijms23137042. [PMID: 35806047 PMCID: PMC9266432 DOI: 10.3390/ijms23137042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/20/2022] [Accepted: 06/22/2022] [Indexed: 02/06/2023] Open
Abstract
QO-58 (5-(2,6-dichloro-5-fluoropyridin-3-yl)-3-phenyl-2-(trifluoromethyl)-1H-pyrazolol[1,5-a]pyrimidin-7-one) has been regarded to be an activator of KV7 channels with analgesic properties. However, whether and how the presence of this compound can result in any modifications of other types of membrane ion channels in native cells are not thoroughly investigated. In this study, we investigated its perturbations on M-type K+ current (IK(M)), Ca2+-activated K+ current (IK(Ca)), large-conductance Ca2+-activated K+ (BKCa) channels, and erg-mediated K+ current (IK(erg)) identified from pituitary tumor (GH3) cells. Addition of QO-58 can increase the amplitude of IK(M) and IK(Ca) in a concentration-dependent fashion, with effective EC50 of 3.1 and 4.2 μM, respectively. This compound could shift the activation curve of IK(M) toward a leftward direction with being void of changes in the gating charge. The strength in voltage-dependent hysteresis (Vhys) of IK(M) evoked by upright triangular ramp pulse (Vramp) was enhanced by adding QO-58. The probabilities of M-type K+ (KM) channels that will be open increased upon the exposure to QO-58, although no modification in single-channel conductance was seen. Furthermore, GH3-cell exposure to QO-58 effectively increased the amplitude of IK(Ca) as well as enhanced the activity of BKCa channels. Under inside-out configuration, QO-58, applied at the cytosolic leaflet of the channel, activated BKCa-channel activity, and its increase could be attenuated by further addition of verruculogen, but not by linopirdine (10 μM). The application of QO-58 could lead to a leftward shift in the activation curve of BKCa channels with neither change in the gating charge nor in single-channel conductance. Moreover, cell exposure of QO-58 (10 μM) resulted in a minor suppression of IK(erg) amplitude in response to membrane hyperpolarization. The docking results also revealed that there are possible interactions of the QO-58 molecule with the KCNQ or KCa1.1 channel. Overall, dual activation of IK(M) and IK(Ca) caused by the presence of QO-58 eventually may have high impacts on the functional activity (e.g., anti-nociceptive effect) residing in electrically excitable cells. Care must be exercised when interpreting data generated with QO-58 as it is not entirely KCNQ/KV7 selective.
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Cho HY, Chuang TH, Wu SN. The Effectiveness in Activating M-Type K + Current Produced by Solifenacin ([(3R)-1-azabicyclo[2.2.2]octan-3-yl] (1S)-1-phenyl-3,4-dihydro-1H-isoquinoline-2-carboxylate): Independent of Its Antimuscarinic Action. Int J Mol Sci 2021; 22:ijms222212399. [PMID: 34830281 PMCID: PMC8622881 DOI: 10.3390/ijms222212399] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 11/08/2021] [Accepted: 11/15/2021] [Indexed: 12/18/2022] Open
Abstract
Solifenacin (Vesicare®, SOL), known to be a member of isoquinolines, is a muscarinic antagonist that has anticholinergic effect, and it has been beneficial in treating urinary incontinence and neurogenic detrusor overactivity. However, the information regarding the effects of SOL on membrane ionic currents is largely uncertain, despite its clinically wide use in patients with those disorders. In this study, the whole-cell current recordings revealed that upon membrane depolarization in pituitary GH3 cells, the exposure to SOL concentration-dependently increased the amplitude of M-type K+ current (IK(M)) with effective EC50 value of 0.34 μM. The activation time constant of IK(M) was concurrently shortened in the SOL presence, hence yielding the KD value of 0.55 μM based on minimal reaction scheme. As cells were exposed to SOL, the steady-state activation curve of IK(M) was shifted along the voltage axis to the left with no change in the gating charge of the current. Upon an isosceles-triangular ramp pulse, the hysteretic area of IK(M) was increased by adding SOL. As cells were continually exposed to SOL, further application of acetylcholine (1 μM) failed to modify SOL-stimulated IK(M); however, subsequent addition of thyrotropin releasing hormone (TRH, 1 μM) was able to counteract SOL-induced increase in IK(M) amplitude. In cell-attached single-channel current recordings, bath addition of SOL led to an increase in the activity of M-type K+ (KM) channels with no change in the single channel conductance; the mean open time of the channel became lengthened. In whole-cell current-clamp recordings, the SOL application reduced the firing of action potentials (APs) in GH3 cells; however, either subsequent addition of TRH or linopirdine was able to reverse SOL-mediated decrease in AP firing. In hippocampal mHippoE-14 neurons, the IK(M) was also stimulated by adding SOL. Altogether, findings from this study disclosed for the first time the effectiveness of SOL in interacting with KM channels and hence in stimulating IK(M) in electrically excitable cells, and this noticeable action appears to be independent of its antagonistic activity on the canonical binding to muscarinic receptors expressed in GH3 or mHippoE-14 cells.
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Affiliation(s)
- Hsin-Yen Cho
- Department of Physiology, National Cheng Kung University Medical College, Tainan City 70101, Taiwan; (H.-Y.C.); (T.-H.C.)
| | - Tzu-Hsien Chuang
- Department of Physiology, National Cheng Kung University Medical College, Tainan City 70101, Taiwan; (H.-Y.C.); (T.-H.C.)
| | - Sheng-Nan Wu
- Department of Physiology, National Cheng Kung University Medical College, Tainan City 70101, Taiwan; (H.-Y.C.); (T.-H.C.)
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan City 70101, Taiwan
- Correspondence: ; Tel.: +886-6-2353535-5334; Fax: +886-6-2362780
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Nikitin ES, Vinogradova LV. Potassium channels as prominent targets and tools for the treatment of epilepsy. Expert Opin Ther Targets 2021; 25:223-235. [PMID: 33754930 DOI: 10.1080/14728222.2021.1908263] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION K+ channels are of great interest to epilepsy research as mutations in their genes are found in humans with inherited epilepsy. At the level of cellular physiology, K+ channels control neuronal intrinsic excitability and are the main contributors to membrane repolarization of active neurons. Recently, a genetically modified voltage-dependent K+ channel has been patented as a remedy for epileptic seizures. AREAS COVERED We review the role of potassium channels in excitability, clinical and experimental evidence for the association of potassium channelopathies with epilepsy, the targeting of K+ channels by drugs, and perspectives of gene therapy in epilepsy with the expression of extra K+ channels in the brain. EXPERT OPINION Control over K+ conductance is of great potential benefit for the treatment of epilepsy. Nowadays, gene therapy affecting K+ channels is one of the most promising approaches to treat pharmacoresistant focal epilepsy.
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Affiliation(s)
- E S Nikitin
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - L V Vinogradova
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
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Lo YC, Lin CL, Fang WY, Lőrinczi B, Szatmári I, Chang WH, Fülöp F, Wu SN. Effective Activation by Kynurenic Acid and Its Aminoalkylated Derivatives on M-Type K + Current. Int J Mol Sci 2021; 22:ijms22031300. [PMID: 33525680 PMCID: PMC7865226 DOI: 10.3390/ijms22031300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/25/2021] [Accepted: 01/26/2021] [Indexed: 12/24/2022] Open
Abstract
Kynurenic acid (KYNA, 4-oxoquinoline-2-carboxylic acid), an intermediate of the tryptophan metabolism, has been recognized to exert different neuroactive actions; however, the need of how it or its aminoalkylated amide derivative N-(2-(dimethylamino)ethyl)-3-(morpholinomethyl)-4-oxo-1,4-dihydroquinoline-2-carboxamide (KYNA-A4) exerts any effects on ion currents in excitable cells remains largely unmet. In this study, the investigations of how KYNA and other structurally similar KYNA derivatives have any adjustments on different ionic currents in pituitary GH3 cells and hippocampal mHippoE-14 neurons were performed by patch-clamp technique. KYNA or KYNA-A4 increased the amplitude of M-type K+ current (IK(M)) and concomitantly enhanced the activation time course of the current. The EC50 value required for KYNA- or KYNA-A4 -stimulated IK(M) was yielded to be 18.1 or 6.4 μM, respectively. The presence of KYNA or KYNA-A4 shifted the relationship of normalized IK(M)-conductance versus membrane potential to more depolarized potential with no change in the gating charge of the current. The voltage-dependent hysteretic area of IK(M) elicited by long-lasting triangular ramp pulse was observed in GH3 cells and that was increased during exposure to KYNA or KYNA-A4. In cell-attached current recordings, addition of KYNA raised the open probability of M-type K+ channels, along with increased mean open time of the channel. Cell exposure to KYNA or KYNA-A4 mildly inhibited delayed-rectifying K+ current; however, neither erg-mediated K+ current, hyperpolarization-activated cation current, nor voltage-gated Na+ current in GH3 cells was changed by KYNA or KYNA-A4. Under whole-cell, current-clamp recordings, exposure to KYNA or KYNA-A4 diminished the frequency of spontaneous action potentials; moreover, their reduction in firing frequency was attenuated by linopirdine, yet not by iberiotoxin or apamin. In hippocampal mHippoE-14 neurons, the addition of KYNA also increased the IK(M) amplitude effectively. Taken together, the actions presented herein would be one of the noticeable mechanisms through which they modulate functional activities of excitable cells occurring in vivo.
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Affiliation(s)
- Yi-Ching Lo
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
- Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (Y.-C.L.); (S.-N.W.); Tel.: +886-7-3234686 (Y.-C.L.); +886-6-2353535-5334 (S.-N.W.); Fax: +886-7-3234686 (Y.-C.L.); +886-6-2362780 (S.-N.W.)
| | - Chih-Lung Lin
- Department of Neurosurgery, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan;
- Department of Neurosurgery, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Wei-Yu Fang
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
| | - Bálint Lőrinczi
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
| | - István Szatmári
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
| | - Wan-Hsuan Chang
- Department of Pharmacology, School of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan; (W.-Y.F.); (W.-H.C.)
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Ferenc Fülöp
- Institute of Pharmaceutical Chemistry, University of Szeged, Eötvös u. 6, H-6720 Szeged, Hungary; (B.L.); (I.S.); (F.F.)
- MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, Eötvös u. 6, H-6720 Szeged, Hungary
| | - Sheng-Nan Wu
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan City 70101, Taiwan
- Department of Physiology, National Cheng Kung University Medical College, Tainan City 70101, Taiwan
- Correspondence: (Y.-C.L.); (S.-N.W.); Tel.: +886-7-3234686 (Y.-C.L.); +886-6-2353535-5334 (S.-N.W.); Fax: +886-7-3234686 (Y.-C.L.); +886-6-2362780 (S.-N.W.)
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Pei Z, Shi M, Guo J, Shen B. Heart Rate Variability Based Prediction of Personalized Drug Therapeutic Response: The Present Status and the Perspectives. Curr Top Med Chem 2020; 20:1640-1650. [PMID: 32493191 DOI: 10.2174/1568026620666200603105002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 02/28/2020] [Accepted: 03/02/2020] [Indexed: 02/08/2023]
Abstract
Heart rate variability (HRV) signals are reported to be associated with the personalized drug
response in many diseases such as major depressive disorder, epilepsy, chronic pain, hypertension, etc.
But the relationships between HRV signals and the personalized drug response in different diseases and
patients are complex and remain unclear. With the fast development of modern smart sensor technologies
and the popularization of big data paradigm, more and more data on the HRV and drug response
will be available, it then provides great opportunities to build models for predicting the association of
the HRV with personalized drug response precisely. We here review the present status of the HRV data
resources and models for predicting and evaluating of personalized drug responses in different diseases.
The future perspectives on the integration of knowledge and personalized data at different levels such as,
genomics, physiological signals, etc. for the application of HRV signals to the precision prediction of
drug therapy and their response will be provided.
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Affiliation(s)
- Zejun Pei
- Nanjing Medical University Affiliated Wuxi Second Hospital, No. 68,Zhongshan road, Wuxi, Jiangsu, China
| | - Manhong Shi
- Centre for Systems Biology, Soochow University, Suzhou 215006, China
| | - Junping Guo
- The Affiliated Yixing Hospital of Jiangsu University, No. 75, Tongzhenguan Road, Yixing, Jiangsu, China
| | - Bairong Shen
- Institutes for Systems Genetics, West China Hospital, Sichuan University, Chengdu, China
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Abstract
Voltage-gated Kv1.1 potassium channel α-subunits are broadly expressed in the nervous system where they act as critical regulators of neuronal excitability. Mutations in the KCNA1 gene, which encodes Kv1.1, are associated with the neurological diseases episodic ataxia and epilepsy. Studies in mouse models have shown that Kv1.1 is important for neural control of the heart and that Kcna1 deletion leads to cardiac dysfunction that appears to be brain-driven. Traditionally, KCNA1 was not believed to be expressed in the heart. However, recent studies have revealed that Kv1.1 subunits are not only present in cardiomyocytes, but that they also make an important heart-intrinsic functional contribution to outward K+ currents and action potential repolarization. This review recounts the winding history of discovery of KCNA1 gene expression and neurocardiac function from fruit flies to mammals and from brain to heart and looks at some of the salient questions that remain to be answered regarding emerging cardiac roles of Kv1.1.
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Affiliation(s)
- Edward Glasscock
- a Department of Biological Sciences , Southern Methodist University , Dallas , TX , USA
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9
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Trosclair K, Dhaibar HA, Gautier NM, Mishra V, Glasscock E. Neuron-specific Kv1.1 deficiency is sufficient to cause epilepsy, premature death, and cardiorespiratory dysregulation. Neurobiol Dis 2020; 137:104759. [PMID: 31978607 DOI: 10.1016/j.nbd.2020.104759] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 01/03/2020] [Accepted: 01/20/2020] [Indexed: 12/14/2022] Open
Abstract
Sudden unexpected death in epilepsy (SUDEP) is the leading cause of epilepsy-related mortality, but the precise cellular substrates involved remain elusive. Epilepsy-associated ion channel genes with co-expression in brain and heart have been proposed as SUDEP candidate genes since they provide a singular unifying link between seizures and lethal cardiac arrhythmias. Here, we generated a conditional knockout (cKO) mouse with neuron-specific deletion of Kcna1, a SUDEP-associated gene with brain-heart co-expression, to test whether seizure-evoked cardiac arrhythmias and SUDEP require the absence of Kv1.1 in both brain and heart or whether ablation in neurons is sufficient. To obtain cKO mice, we developed a floxed Kcna1 mouse which we crossed to mice with the Synapsin1-Cre transgene, which selectively deletes Kcna1 in most neurons. Molecular analyses confirmed neuron-specific Kcna1 deletion in cKO mice and corresponding loss of Kv1.1 except in cerebellum where Synapsin1-Cre is not highly expressed. Survival studies and electroencephalography, electrocardiography, and plethysmography recordings showed that cKO mice exhibit premature death, epilepsy, and cardiorespiratory dysregulation but to a lesser degree than global knockouts. Heart rate variability (HRV) was increased in cKO mice with peaks during daytime suggesting disturbed diurnal HRV patterns as a SUDEP biomarker. Residual Kv1.1 expression in cKO cerebellum suggests it may play an unexpected role in regulating ictal cardiorespiratory dysfunction and SUDEP risk. This work demonstrates the principle that channelopathies with brain-heart expression patterns can increase death risk by brain-driven mechanisms alone without a functionally compromised heart, reinforcing seizure control as a primary clinical strategy for SUDEP prevention.
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Affiliation(s)
- Krystle Trosclair
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center Shreveport, LA 71103, United States of America.
| | - Hemangini A Dhaibar
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center Shreveport, LA 71103, United States of America.
| | - Nicole M Gautier
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center Shreveport, LA 71103, United States of America.
| | - Vikas Mishra
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center Shreveport, LA 71103, United States of America.
| | - Edward Glasscock
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center Shreveport, LA 71103, United States of America; Department of Biological Sciences, Southern Methodist University, Dallas, TX 75275, United States of America.
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10
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Li BG, Wu WJ, Zheng HC, Yang HF, Zuo YX, Cui XP. Long noncoding RNA GAS5 silencing inhibits the expression of KCNQ3 by sponging miR-135a-5p to prevent the progression of epilepsy. Kaohsiung J Med Sci 2019; 35:527-534. [PMID: 31373759 DOI: 10.1002/kjm2.12102] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 06/03/2019] [Indexed: 02/06/2023] Open
Abstract
Epilepsy is one of the most common neurological disorders in humans. Recently, long noncoding RNAs (lncRNAs) have been reported to be important players in neurological diseases. Herein, this study aimed to examine the effect of lncRNA GAS5 on the occurrence of epilepsy in rat and cell models of epileptic seizure. The expression of lncRNA GAS5 was measured in the established rat and cell models. The binding sites between lncRNA GAS5 and miR-135a-5p, as well as those between miR-135a-5p and 3' untranslated region of KCNQ3 were predicted by miRDB and Targetscan, separately, followed by verification using dual-luciferase reporter gene assay. The expression of miR-135a-5p was measured in response to the overexpression of lncRNA GAS5. The mRNA and protein levels of KCNQ3 were examined in response to overexpression of miR-135a-5p. Next, the latency of epilepsy and frequency of epileptic seizures were assessed in rats injected with Lv-shGAS5 and Lv-miR-135a-5p in epileptic seizure model. In the rat and cell models, lncRNA GAS5 was highly expressed when epileptic seizure was induced. The expression of miR-135a-5p was decreased by overexpression of lncRNA GAS5. Meanwhile, the mRNA and protein levels of KCNQ3 were decreased in response to knockdown of miR-135a-5p. After the treatment of Lv-shGAS5 and Lv-miR-135a-5p, the average latent period of epilepsy was prolonged and the frequency of seizures was decreased. The key findings of the present study provide evidence emphasizing that lncRNA GAS5 functions as a competitive endogenous RNA of miR-135a-5p to increase expression of KCNQ3, and lncRNA GAS5 silencing inhibited the occurrence and progression of epilepsy.
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Affiliation(s)
- Bao-Guang Li
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
| | - Wen-Juan Wu
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
| | - Hua-Cheng Zheng
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
| | - Hua-Fang Yang
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
| | - Yue-Xian Zuo
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
| | - Xiao-Pu Cui
- Department of Neurology, Children's Hospital of Hebei Province, Shijiazhuang, Hebei, China
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11
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Derera ID, Smith KC, Smith BN. Altered A-type potassium channel function in the nucleus tractus solitarii in acquired temporal lobe epilepsy. J Neurophysiol 2018; 121:177-187. [PMID: 30517061 DOI: 10.1152/jn.00556.2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Sudden unexpected death in epilepsy (SUDEP) is among the leading causes of death in people with epilepsy. Individuals with temporal lobe epilepsy (TLE) have a high risk for SUDEP because the seizures are often medically intractable. Neurons in the nucleus tractus solitarii (NTS) have been implicated in mouse models of SUDEP and play a critical role in modulating cardiorespiratory and autonomic output. Increased neuronal excitability of inhibitory, GABAergic neurons in the NTS develops during epileptogenesis, and NTS dysfunction has been implicated in mouse models of SUDEP. In this study we used the pilocarpine-induced status epilepticus model of TLE (i.e., pilo-SE mice) to investigate the A-type voltage-gated K+ channel as a potential contributor to increased excitability in GABAergic NTS neurons during epileptogenesis. Compared with age-matched control mice, pilo-SE mice displayed an increase in spontaneous action potential frequency and half-width 9-12 wk after treatment. Activity of GABAergic NTS neurons from pilo-SE mice showed less sensitivity to 4-aminopyridine. Correspondingly, reduced A-type K+ current amplitude was detected in these neurons, with no change in activation or inactivation kinetics. No changes were observed in Kv4.1, Kv4.2, Kv4.3, KChIP1, KChIP3, or KChIP4 mRNA expression. These changes contribute to the increased excitability in GABAergic NTS neurons that develops in TLE and may provide insight into potential mechanisms contributing to the increased risk for cardiorespiratory collapse and SUDEP in this model. NEW & NOTEWORTHY Sudden unexpected death in epilepsy (SUDEP) is a leading cause of death in epilepsy, and dysfunction in central autonomic neurons may play a role. In a mouse model of acquired epilepsy, GABAergic neurons in the nucleus tractus solitarii developed a reduced amplitude of the A-type current, which contributes to the increased excitability seen in these neurons during epileptogenesis. Neuronal excitability changes in inhibitory central vagal circuitry may increase the risk for cardiorespiratory collapse and SUDEP.
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Affiliation(s)
- Isabel D Derera
- Department of Physiology, College of Medicine, University of Kentucky , Lexington, Kentucky
| | - Katalin Cs Smith
- Department of Physiology, College of Medicine, University of Kentucky , Lexington, Kentucky.,Department of Neuroscience, College of Medicine, University of Kentucky , Lexington, Kentucky
| | - Bret N Smith
- Department of Physiology, College of Medicine, University of Kentucky , Lexington, Kentucky.,Department of Neuroscience, College of Medicine, University of Kentucky , Lexington, Kentucky.,Epilepsy Research Center, University of Kentucky , Lexington, Kentucky
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