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Li K, McClenahan SJ, Han C, Bungard JD, Rathnayake U, Boutaud O, Bauer JA, Days EL, Lindsley CW, Shelton EL, Denton JS. Discovery and Characterization of VU0542270, the First Selective Inhibitor of Vascular Kir6.1/SUR2B K ATP Channels. Mol Pharmacol 2024; 105:202-212. [PMID: 38302135 PMCID: PMC10877733 DOI: 10.1124/molpharm.123.000783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 12/21/2023] [Accepted: 01/02/2024] [Indexed: 02/03/2024] Open
Abstract
Vascular smooth muscle KATP channels critically regulate blood flow and blood pressure by modulating vascular tone and therefore represent attractive drug targets for treating several cardiovascular disorders. However, the lack of potent inhibitors that can selectively inhibit Kir6.1/SUR2B (vascular KATP) over Kir6.2/SUR1 (pancreatic KATP) has eluded discovery despite decades of intensive research. We therefore screened 47,872 chemically diverse compounds for novel inhibitors of heterologously expressed Kir6.1/SUR2B channels. The most potent inhibitor identified in the screen was an N-aryl-N'-benzyl urea compound termed VU0542270. VU0542270 inhibits Kir6.1/SUR2B with an IC50 of approximately 100 nM but has no apparent activity toward Kir6.2/SUR1 or several other members of the Kir channel family at doses up to 30 µM (>300-fold selectivity). By expressing different combinations of Kir6.1 or Kir6.2 with SUR1, SUR2A, or SUR2B, the VU0542270 binding site was localized to SUR2. Initial structure-activity relationship exploration around VU0542270 revealed basic texture related to structural elements that are required for Kir6.1/SUR2B inhibition. Analysis of the pharmacokinetic properties of VU0542270 showed that it has a short in vivo half-life due to extensive metabolism. In pressure myography experiments on isolated mouse ductus arteriosus vessels, VU0542270 induced ductus arteriosus constriction in a dose-dependent manner similar to that of the nonspecific KATP channel inhibitor glibenclamide. The discovery of VU0542270 provides conceptual proof that SUR2-specific KATP channel inhibitors can be developed using a molecular target-based approach and offers hope for developing cardiovascular therapeutics targeting Kir6.1/SUR2B. SIGNIFICANCE STATEMENT: Small-molecule inhibitors of vascular smooth muscle KATP channels might represent novel therapeutics for patent ductus arteriosus, migraine headache, and sepsis; however, the lack of selective channel inhibitors has slowed progress in these therapeutic areas. Here, this study describes the discovery and characterization of the first vascular-specific KATP channel inhibitor, VU0542270.
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Affiliation(s)
- Kangjun Li
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Samantha J McClenahan
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Changho Han
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Joseph D Bungard
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Upendra Rathnayake
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Olivier Boutaud
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Joshua A Bauer
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Emily L Days
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Craig W Lindsley
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Elaine L Shelton
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
| | - Jerod S Denton
- Departments of Anesthesiology (K.L., S.J.M., J.S.D.), Pharmacology (K.L., C.H., J.D.B., U.R., O.B., C.W.L., J.S.D.), Pediatrics (E.L.S.), and Biochemistry (J.A.B.), Vanderbilt University Medical Center, Nashville, Tennessee and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee (J.A.B., E.L.D., J.S.D.)
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Zhou X, Zhao C, Xu H, Xu Y, Zhan L, Wang P, He J, Lu T, Gu Y, Yang Y, Xu C, Chen Y, Liu Y, Zeng Y, Tian F, Chen Q, Xie X, Liu J, Hu H, Li J, Zheng Y, Guo J, Gao Z. Pharmacological inhibition of Kir4.1 evokes rapid-onset antidepressant responses. Nat Chem Biol 2024:10.1038/s41589-024-01555-y. [PMID: 38355723 DOI: 10.1038/s41589-024-01555-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: 02/06/2023] [Accepted: 01/15/2024] [Indexed: 02/16/2024]
Abstract
Major depressive disorder, a prevalent and severe psychiatric condition, necessitates development of new and fast-acting antidepressants. Genetic suppression of astrocytic inwardly rectifying potassium channel 4.1 (Kir4.1) in the lateral habenula ameliorates depression-like phenotypes in mice. However, Kir4.1 remains an elusive drug target for depression. Here, we discovered a series of Kir4.1 inhibitors through high-throughput screening. Lys05, the most potent one thus far, effectively suppressed native Kir4.1 channels while displaying high selectivity against established targets for rapid-onset antidepressants. Cryogenic-electron microscopy structures combined with electrophysiological characterizations revealed Lys05 directly binds in the central cavity of Kir4.1. Notably, a single dose of Lys05 reversed the Kir4.1-driven depression-like phenotype and exerted rapid-onset (as early as 1 hour) antidepressant actions in multiple canonical depression rodent models with efficacy comparable to that of (S)-ketamine. Overall, we provided a proof of concept that Kir4.1 is a promising target for rapid-onset antidepressant effects.
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Affiliation(s)
- Xiaoyu Zhou
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- College of Pharmacy, University of Chinese Academy of Sciences, Beijing, China
| | - Cheng Zhao
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Haiyan Xu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China
| | - Yixiang Xu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Li Zhan
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Pei Wang
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Jingyi He
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
- School of Pharmacy, Henan University, Kaifeng, China
| | - Taotao Lu
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Yueling Gu
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Yan Yang
- Liangzhu Laboratory, Zhejiang University School of Medicine, New Cornerstone Science Laboratory, Zhejiang University, Hangzhou, China
| | - Chanjuan Xu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Yiyang Chen
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Yuxuan Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Yue Zeng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Fuyun Tian
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zhongshan, China
| | - Qian Chen
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xin Xie
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
| | - Jianfeng Liu
- Cellular Signaling Laboratory, Key Laboratory of Molecular Biophysics of Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Hailan Hu
- Liangzhu Laboratory, Zhejiang University School of Medicine, New Cornerstone Science Laboratory, Zhejiang University, Hangzhou, China
| | - Jian Li
- State Key Laboratory of Bioreactor Engineering, Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism, Frontiers Science Center for Materiobiology and Dynamic Chemistry, Shanghai Key Laboratory of New Drug Design, School of Pharmacy, East China University of Science and Technology, Shanghai, China
| | - Yueming Zheng
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
| | - Jiangtao Guo
- Department of Biophysics and Department of Neurology of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
| | - Zhaobing Gao
- State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China.
- College of Pharmacy, University of Chinese Academy of Sciences, Beijing, China.
- School of Chinese Materia Medica, Nanjing University of Chinese Medicine, Nanjing, China.
- School of Pharmacy, Henan University, Kaifeng, China.
- Zhongshan Institute for Drug Discovery, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Zhongshan, China.
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Yang X, Wu Y, Xu S, Li H, Peng C, Cui X, Dhoomun DK, Wang G, Xu T, Dong M, Li X, Du Y. Targeting the inward rectifier potassium channel 5.1 in thyroid cancer: artificial intelligence-facilitated molecular docking for drug discovery. BMC Endocr Disord 2023; 23:113. [PMID: 37208644 DOI: 10.1186/s12902-023-01360-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 05/04/2023] [Indexed: 05/21/2023] Open
Abstract
BACKGROUND Recurrent and metastatic thyroid cancer is more invasive and can transform to dedifferentiated thyroid cancer, thus leading to a severe decline in the 10-year survival. The thyroid-stimulating hormone receptor (TSHR) plays an important role in differentiation process. We aim to find a therapeutic target in redifferentiation strategies for thyroid cancer. METHODS Our study integrated the differentially expressed genes acquired from the Gene Expression Omnibus database by comparing TSHR expression levels in the Cancer Genome Atlas database. We conducted functional enrichment analysis and verified the expression of these genes by RT-PCR in 68 pairs of thyroid tumor and paratumor tissues. Artificial intelligence-enabled virtual screening was combined with the VirtualFlow platform for deep docking. RESULTS We identified five genes (KCNJ16, SLC26A4, TG, TPO, and SYT1) as potential cancer treatment targets. TSHR and KCNJ16 were downregulated in the thyroid tumor tissues, compared with paired normal tissues. In addition, KCNJ16 was lower in the vascular/capsular invasion group. Enrichment analyses revealed that KCNJ16 may play a significant role in cell growth and differentiation. The inward rectifier potassium channel 5.1 (Kir5.1, encoded by KCNJ16) emerged as an interesting target in thyroid cancer. Artificial intelligence-facilitated molecular docking identified Z2087256678_2, Z2211139111_1, Z2211139111_2, and PV-000592319198_1 (-7.3 kcal/mol) as the most potent commercially available molecular targeting Kir5.1. CONCLUSION This study may provide greater insights into the differentiation features associated with TSHR expression in thyroid cancer, and Kir5.1 may be a potential therapeutic target in the redifferentiation strategies for recurrent and metastatic thyroid cancer.
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Affiliation(s)
- Xue Yang
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Yonglin Wu
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Shaojie Xu
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Hanning Li
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Chengcheng Peng
- Department of Thyroid and Breast Surgery, Huanggang Central Hospital, Huanggang, Hubei, People's Republic of China
| | - Xiaoqing Cui
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Deenraj Kush Dhoomun
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Ge Wang
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Tao Xu
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Department of Obstetrics and Gynecology, Cancer Biology research center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Menglu Dong
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China
| | - Xingrui Li
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
| | - Yaying Du
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
- Laboratory of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
- Laboratory of General Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People's Republic of China.
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Janjic P, Solev D, Kocarev L. Non-trivial dynamics in a model of glial membrane voltage driven by open potassium pores. Biophys J 2023; 122:1470-1490. [PMID: 36919241 PMCID: PMC10147837 DOI: 10.1016/j.bpj.2023.03.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 02/01/2023] [Accepted: 03/07/2023] [Indexed: 03/16/2023] Open
Abstract
Despite the molecular evidence that a nearly linear steady-state current-voltage relationship in mammalian astrocytes reflects a total current resulting from more than one differentially regulated K+ conductance, detailed ordinary differential equation (ODE) models of membrane voltage Vm are still lacking. Various experimental results reporting altered rectification of the major Kir currents in glia, dominated by Kir4.1, have motivated us to develop a detailed model of Vm dynamics incorporating the weaker potassium K2P-TREK1 current in addition to Kir4.1, and study the stability of the resting state Vr. The main question is whether, with the loss of monotonicity in glial I-V curve resulting from altered Kir rectification, the nominal resting state Vr remains stable, and the cell retains the trivial, potassium electrode behavior with Vm after EK. The minimal two-dimensional model of Vm near Vr showed that an N-shape deformed Kir I-V curve induces multistability of Vm in a model that incorporates K2P activation kinetics, and nonspecific K+ leak currents. More specifically, an asymmetrical, nonlinear decrease of outward Kir4.1 conductance, turning the channels into inward rectifiers, introduces instability of Vr. That happens through a robust bifurcation giving birth to a second, more depolarized stable resting state Vdr > -10 mV. Realistic recordings from electrographic seizures were used to perturb the model. Simulations of the model perturbed by constant current through gap junctions and seizure-like discharges as local field potentials led to depolarization and switching of Vm between the two stable states, in a downstate-upstate manner. In the event of prolonged depolarizations near Vdr, such catastrophic instability would affect all aspects of the glial function, from metabolic support to membrane transport, and practically all neuromodulatory roles assigned to glia.
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Affiliation(s)
- Predrag Janjic
- Laboratory for Complex Systems and Networks, Research Centre for Computer Science and Information Technologies, Macedonian Academy of Sciences and Arts, Skopje, North Macedonia.
| | - Dimitar Solev
- Laboratory for Complex Systems and Networks, Research Centre for Computer Science and Information Technologies, Macedonian Academy of Sciences and Arts, Skopje, North Macedonia
| | - Ljupco Kocarev
- Laboratory for Complex Systems and Networks, Research Centre for Computer Science and Information Technologies, Macedonian Academy of Sciences and Arts, Skopje, North Macedonia
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Zhang C, Guo J. Diverse functions of the inward-rectifying potassium channel Kir5.1 and its relationship with human diseases. Front Physiol 2023; 14:1127893. [PMID: 36923292 PMCID: PMC10008857 DOI: 10.3389/fphys.2023.1127893] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 02/15/2023] [Indexed: 03/02/2023] Open
Abstract
The inward-rectifying potassium channel subunit Kir5.1, encoded by Kcnj16, can form functional heteromeric channels (Kir4.1/5.1 and Kir4.2/5.1) with Kir4.1 (encoded by Kcnj10) or Kir4.2 (encoded by Kcnj15). It is expressed in the kidneys, pancreas, thyroid, brain, and other organs. Although Kir5.1 cannot form functional homomeric channels in most cases, an increasing number of studies in recent years have found that the functions of this subunit should not be underestimated. Kir5.1 can confer intracellular pH sensitivity to Kir4.1/5.1 channels, which can act as extracellular potassium sensors in the renal distal convoluted tubule segment. This segment plays an important role in maintaining potassium and acid-base balances. This review summarizes the various pathophysiological processes involved in Kir5.1 and the expression changes of Kir5.1 as a differentially expressed gene in various cancers, as well as describing several other disease phenotypes caused by Kir5.1 dysfunction.
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Affiliation(s)
- Chaojie Zhang
- Nephrology Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Institute of Nephrology, Zhengzhou University, Zhengzhou, China.,Henan Province Research Center for Kidney Disease, Zhengzhou, China.,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, China
| | - Jia Guo
- Nephrology Research Center, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,Institute of Nephrology, Zhengzhou University, Zhengzhou, China.,Henan Province Research Center for Kidney Disease, Zhengzhou, China.,Key Laboratory of Precision Diagnosis and Treatment for Chronic Kidney Disease in Henan Province, Zhengzhou, China
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Staruschenko A, Hodges MR, Palygin O. Kir5.1 channels: potential role in epilepsy and seizure disorders. Am J Physiol Cell Physiol 2022; 323:C706-C717. [PMID: 35848616 PMCID: PMC9448276 DOI: 10.1152/ajpcell.00235.2022] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 07/06/2022] [Accepted: 07/08/2022] [Indexed: 11/22/2022]
Abstract
Inwardly rectifying potassium (Kir) channels are broadly expressed in many mammalian organ systems, where they contribute to critical physiological functions. However, the importance and function of the Kir5.1 channel (encoded by the KCNJ16 gene) have not been fully recognized. This review focuses on the recent advances in understanding the expression patterns and functional roles of Kir5.1 channels in fundamental physiological systems vital to potassium homeostasis and neurological disorders. Recent studies have described the role of Kir5.1-forming Kir channels in mouse and rat lines with mutations in the Kcnj16 gene. The animal research reveals distinct renal and neurological phenotypes, including pH and electrolyte imbalances, blunted ventilatory responses to hypercapnia/hypoxia, and seizure disorders. Furthermore, it was confirmed that these phenotypes are reminiscent of those in patient cohorts in which mutations in the KCNJ16 gene have also been identified, further suggesting a critical role for Kir5.1 channels in homeostatic/neural systems health and disease. Future studies that focus on the many functional roles of these channels, expanded genetic screening in human patients, and the development of selective small-molecule inhibitors for Kir5.1 channels, will continue to increase our understanding of this unique Kir channel family member.
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Affiliation(s)
- Alexander Staruschenko
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, Florida
- Hypertension and Kidney Research Center, University of South Florida, Tampa, Florida
- James A. Haley Veterans Hospital, Tampa, Florida
| | - Matthew R Hodges
- Department of Physiology and Neuroscience Research Center, Medical College of Wisconsin, Milwaukee, Wisconsin
| | - Oleg Palygin
- Division of Nephrology, Department of Medicine, Medical University of South Carolina, Charleston, South Carolina
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