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Pio-Lopez L, Levin M. Aging as a loss of morphostatic information: A developmental bioelectricity perspective. Ageing Res Rev 2024; 97:102310. [PMID: 38636560 DOI: 10.1016/j.arr.2024.102310] [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: 11/05/2023] [Revised: 02/21/2024] [Accepted: 04/12/2024] [Indexed: 04/20/2024]
Abstract
Maintaining order at the tissue level is crucial throughout the lifespan, as failure can lead to cancer and an accumulation of molecular and cellular disorders. Perhaps, the most consistent and pervasive result of these failures is aging, which is characterized by the progressive loss of function and decline in the ability to maintain anatomical homeostasis and reproduce. This leads to organ malfunction, diseases, and ultimately death. The traditional understanding of aging is that it is caused by the accumulation of molecular and cellular damage. In this article, we propose a complementary view of aging from the perspective of endogenous bioelectricity which has not yet been integrated into aging research. We propose a view of aging as a morphostasis defect, a loss of biophysical prepattern information, encoding anatomical setpoints used for dynamic tissue and organ homeostasis. We hypothesize that this is specifically driven by abrogation of the endogenous bioelectric signaling that normally harnesses individual cell behaviors toward the creation and upkeep of complex multicellular structures in vivo. Herein, we first describe bioelectricity as the physiological software of life, and then identify and discuss the links between bioelectricity and life extension strategies and age-related diseases. We develop a bridge between aging and regeneration via bioelectric signaling that suggests a research program for healthful longevity via morphoceuticals. Finally, we discuss the broader implications of the homologies between development, aging, cancer and regeneration and how morphoceuticals can be developed for aging.
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Affiliation(s)
- Léo Pio-Lopez
- Allen Discovery Center, Tufts University, Medford, MA 02155, USA
| | - Michael Levin
- Allen Discovery Center, Tufts University, Medford, MA 02155, USA; Wyss Institute for Biologically Inspired Engineering, Boston, MA 02115, USA.
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Cui F, Wulan T, Zhang Q, Zhang VW, Jiang Y. Identification of a novel KCNT2 variant in a family with developmental and epileptic encephalopathies: a case report and literature review. Front Genet 2024; 15:1371282. [PMID: 38510274 PMCID: PMC10951377 DOI: 10.3389/fgene.2024.1371282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Accepted: 02/20/2024] [Indexed: 03/22/2024] Open
Abstract
Background: Developmental and epileptic encephalopathies (DEEs) are a group of heterogeneous neurodevelopmental diseases characterized mainly by developmental delay/intellectual disability and early-onset epilepsy. Researchers have identified variations in the KCNT2 gene (OMIM* 610044) as the cause of DEE type 57 (MIM# 617771). Case presentation: We report in this study a 46-year-old woman who presented with early-onset epilepsy, intellectual disability, hypertrichosis, coarse facial features, and short stature. Besides, there were four other affected individuals in her family history, including two elder brothers, a younger brother, and their mother. We collected blood samples from the proband, her two affected brothers, and her clinically normal daughter for genetic analysis. Clinical exome sequencing revealed a novel heterozygous variant in the KCNT2 gene (NM_198503: c.188G>A, p.Arg63His) in the proband and her two affected brothers, while her daughter did not carry this variant. Furthermore, we reviewed all 25 patients identified in the literature with KCNT2 variants and compared their phenotypes. Conclusion: Epilepsy and intellectual disability/developmental delay occur in almost all patients with KCNT2 variants. KCNT2-relevant DEEs partially overlap with the clinical phenotypes of KATP channel diseases, particularly in hypertrichosis and distinctive coarse facial features.
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Affiliation(s)
- Fengji Cui
- Department of Molecular Genetics, Chifeng Maternity Hospital, Chifeng, China
| | - Tuoya Wulan
- Department of Reproduction, Chifeng Maternity Hospital, Chifeng, China
| | | | | | - Yuhua Jiang
- Department of Obstetrics, Chifeng Maternity Hospital, Chifeng, China
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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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Daas F, Gupta P, Kiblawi F. Multiple vascular anomalies and refractory pericardial effusion in a young patient with Cantu syndrome: a case report and review of the literature. BMC Pediatr 2023; 23:644. [PMID: 38114927 PMCID: PMC10731865 DOI: 10.1186/s12887-023-04446-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 11/28/2023] [Indexed: 12/21/2023] Open
Abstract
BACKGROUND Cantu syndrome is a rare and complex multisystem disorder characterized by hypertrichosis, facial dysmorphism, osteochondroplasia and cardiac abnormalities. With only 150 cases reported worldwide, Cantu syndrome is now gaining wider recognition due to molecular testing and a growing body of literature that further characterizes the syndrome and some of its most important features. Cardiovascular pathology previously described in the literature include cardiomegaly, pericardial effusion, vascular dilation and tortuosity, and other congenital heart defects. However, cardiovascular involvement is highly variable amongst individuals with Cantu syndrome. In some instances, it can be extensive and severe requiring surgical management and long term follow up. CASE PRESENTATION Herein we report a case of a fourteen-year-old female who presented with worsening pericardial effusion of unknown etiology, and echocardiographic findings of concentric left ventricular hypertrophy, a mildly dilated aortic root and ascending aorta. Her medical history was notable for hemoptysis and an episode of pulmonary hemorrhage secondary to multiple aortopulmonary collaterals that were subsequently embolized in early childhood. She was initially managed with Ibuprofen and Colchicine but continued to worsen, and ultimately required a pericardial window for the management of refractory pericardial effusion. Imaging studies obtained on subsequent visits revealed multiple dilated and tortuous blood vessels in the head, neck, chest, and pelvis. A cardiomyopathy molecular studies panel was sent, and a pathogenic variant was identified in the ABCC9 gene, confirming the molecular diagnosis of autosomal dominant Cantu syndrome. CONCLUSIONS Vascular anomalies and significant cardiac involvement are often present in Cantu syndrome, however there are currently no established screening recommendations or surveillance protocols in place. The triad of hypertrichosis, facial dysmorphism, and unexplained cardiovascular involvement in any patient should raise suspicion for Cantu syndrome and warrant further investigation. Initial cardiac evaluation and follow up should be indicated in any patient with a clinical and/or molecular diagnosis of Cantu syndrome. Furthermore, whole body imaging should be utilized to evaluate the extent of vascular involvement and dictate long term monitoring and care.
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Affiliation(s)
- Falastine Daas
- Department of Pediatrics, St. Joseph's University Medical Center, 703 Main Street, Paterson, NJ, 07503, USA.
| | - Punita Gupta
- Department of Pediatrics Division of Genetics, St. Joseph's University Medical Center, 703 Main Street, Paterson, NJ, 07503, USA
| | - Fuad Kiblawi
- Department of Pediatrics Division of Cardiology, St. Joseph's University Medical Center, 703 Main Street, Paterson, NJ, 07503, USA
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Gao J, McClenaghan C, Matreyek KA, Grange DK, Nichols CG. Rapid Characterization of the Functional and Pharmacological Consequences of Cantú Syndrome K ATP Channel Mutations in Intact Cells. J Pharmacol Exp Ther 2023; 386:298-309. [PMID: 37527933 PMCID: PMC10449099 DOI: 10.1124/jpet.123.001659] [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: 03/24/2023] [Revised: 05/10/2023] [Accepted: 06/01/2023] [Indexed: 08/03/2023] Open
Abstract
Gain-of-function of KATP channels, resulting from mutations in either KCNJ8 (encoding inward rectifier sub-family 6 [Kir6.1]) or ABCC9 (encoding sulphonylurea receptor [SUR2]), cause Cantú syndrome (CS), a channelopathy characterized by excess hair growth, coarse facial appearance, cardiomegaly, and lymphedema. Here, we established a pipeline for rapid analysis of CS mutation consequences in Landing pad HEK 293 cell lines stably expressing wild type (WT) and mutant human Kir6.1 and SUR2B. Thallium-influx and cell membrane potential, reported by fluorescent Tl-sensitive Fluozin-2 and voltage-sensitive bis-(1,3-dibutylbarbituric acid)trimethine oxonol (DiBAC4(3)) dyes, respectively, were used to assess channel activity. In the Tl-influx assay, CS-associated Kir6.1 mutations increased sensitivity to the ATP-sensitive potassium (KATP) channel activator, pinacidil, but there was strikingly little effect of pinacidil for any SUR2B mutations, reflecting unexpected differences in the molecular mechanisms of Kir6.1 versus SUR2B mutations. Compared with the Tl-influx assay, the DiBAC4(3) assay presents more significant signal changes in response to subtle KATP channel activity changes, and all CS mutants (both Kir6.1 and SUR2B), but not WT channels, caused marked hyperpolarization, demonstrating that all mutants were activated under ambient conditions in intact cells. Most SUR2 CS mutations were markedly inhibited by <100 nM glibenclamide, but sensitivity to inhibition by glibenclamide, repaglinide, and PNU37883A was markedly reduced for Kir6.1 CS mutations. Understanding functional consequences of mutations can help with disease diagnosis and treatment. The analysis pipeline we have developed has the potential to rapidly identify mutational consequences, aiding future CS diagnosis, drug discovery, and individualization of treatment. SIGNIFICANCE STATEMENT: We have developed new fluorescence-based assays of channel activities and drug sensitivities of Cantú syndrome (CS) mutations in human Kir6.1/SUR2B-dependent KATP channels, showing that Kir6.1 mutations increase sensitivity to potassium channel openers, while SUR2B mutations markedly reduce K channel opener (KCO) sensitivity. However, both Kir6.1 and SUR2B CS mutations are both more hyperpolarized than WT cells under basal conditions, confirming pathophysiologically relevant gain-of-function, validating DiBAC4(3) fluorescence to characterize hyperpolarization induced by KATP channel activity under basal, non KCO-activated conditions.
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Affiliation(s)
- Jian Gao
- Department of Cell Biology and Physiology (J.G., C.M.C., C.G.N.), Center for the Investigation of Membrane Excitability Diseases (J.G., C.M.C., D.K.G., C.G.N.), and Division of Genetics and Genomic Medicine, Department of Pediatrics (D.K.G.), Washington University in St. Louis, St. Louis, Missouri; and Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio (K.A.M.)
| | - Conor McClenaghan
- Department of Cell Biology and Physiology (J.G., C.M.C., C.G.N.), Center for the Investigation of Membrane Excitability Diseases (J.G., C.M.C., D.K.G., C.G.N.), and Division of Genetics and Genomic Medicine, Department of Pediatrics (D.K.G.), Washington University in St. Louis, St. Louis, Missouri; and Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio (K.A.M.)
| | - Kenneth A Matreyek
- Department of Cell Biology and Physiology (J.G., C.M.C., C.G.N.), Center for the Investigation of Membrane Excitability Diseases (J.G., C.M.C., D.K.G., C.G.N.), and Division of Genetics and Genomic Medicine, Department of Pediatrics (D.K.G.), Washington University in St. Louis, St. Louis, Missouri; and Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio (K.A.M.)
| | - Dorothy K Grange
- Department of Cell Biology and Physiology (J.G., C.M.C., C.G.N.), Center for the Investigation of Membrane Excitability Diseases (J.G., C.M.C., D.K.G., C.G.N.), and Division of Genetics and Genomic Medicine, Department of Pediatrics (D.K.G.), Washington University in St. Louis, St. Louis, Missouri; and Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio (K.A.M.)
| | - Colin G Nichols
- Department of Cell Biology and Physiology (J.G., C.M.C., C.G.N.), Center for the Investigation of Membrane Excitability Diseases (J.G., C.M.C., D.K.G., C.G.N.), and Division of Genetics and Genomic Medicine, Department of Pediatrics (D.K.G.), Washington University in St. Louis, St. Louis, Missouri; and Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio (K.A.M.)
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Hanson A, McClenaghan C, Weng KC, Colijn S, Stratman AN, Halabi CM, Grange DK, Silva JR, Nichols CG. Electrophysiology of human iPSC-derived vascular smooth muscle cells and cell autonomous consequences of Cantu Syndrome mutations. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.29.547088. [PMID: 37425756 PMCID: PMC10327170 DOI: 10.1101/2023.06.29.547088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Objective Cantu Syndrome (CS), a multisystem disease with a complex cardiovascular phenotype, is caused by GoF variants in the Kir6.1/SUR2 subunits of ATP-sensitive potassium (K ATP ) channels, and is characterized by low systemic vascular resistance, as well as tortuous, dilated vessels, and decreased pulse-wave velocity. Thus, CS vascular dysfunction is multifactorial, with distinct hypomyotonic and hyperelastic components. To dissect whether such complexities arise cell-autonomously within vascular smooth muscle cells (VSMCs), or as secondary responses to the pathophysiological milieu, we assessed electrical properties and gene expression in human induced pluripotent stem cell-derived VSMCs (hiPSC-VSMCs), differentiated from control and CS patient-derived hiPSCs, and in native mouse control and CS VSMCs. Approach and Results Whole-cell voltage-clamp of isolated aortic and mesenteric VSMCs isolated from wild type (WT) and Kir6.1[V65M] (CS) mice revealed no difference in voltage-gated K + (K v ) or Ca 2+ currents. K v and Ca 2+ currents were also not different between validated hiPSC-VSMCs differentiated from control and CS patient-derived hiPSCs. Pinacidil-sensitive K ATP currents in control hiPSC-VSMCs were consistent with those in WT mouse VSMCs, and were considerably larger in CS hiPSC-VSMCs. Consistent with lack of any compensatory modulation of other currents, this resulted in membrane hyperpolarization, explaining the hypomyotonic basis of CS vasculopathy. Increased compliance and dilation in isolated CS mouse aortae, was associated with increased elastin mRNA expression. This was consistent with higher levels of elastin mRNA in CS hiPSC-VSMCs, suggesting that the hyperelastic component of CS vasculopathy is a cell-autonomous consequence of vascular K ATP GoF. Conclusions The results show that hiPSC-VSMCs reiterate expression of the same major ion currents as primary VSMCs, validating the use of these cells to study vascular disease. The results further indicate that both the hypomyotonic and hyperelastic components of CS vasculopathy are cell-autonomous phenomena driven by K ATP overactivity within VSMCs.
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McClenaghan C, Mukadam MA, Roeglin J, Tryon RC, Grabner M, Dayal A, Meyer GA, Nichols CG. Skeletal muscle delimited myopathy and verapamil toxicity in SUR2 mutant mouse models of AIMS. EMBO Mol Med 2023; 15:e16883. [PMID: 37154692 PMCID: PMC10245035 DOI: 10.15252/emmm.202216883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 04/10/2023] [Accepted: 04/17/2023] [Indexed: 05/10/2023] Open
Abstract
ABCC9-related intellectual disability and myopathy syndrome (AIMS) arises from loss-of-function (LoF) mutations in the ABCC9 gene, which encodes the SUR2 subunit of ATP-sensitive potassium (KATP ) channels. KATP channels are found throughout the cardiovascular system and skeletal muscle and couple cellular metabolism to excitability. AIMS individuals show fatigability, muscle spasms, and cardiac dysfunction. We found reduced exercise performance in mouse models of AIMS harboring premature stop codons in ABCC9. Given the roles of KATP channels in all muscles, we sought to determine how myopathy arises using tissue-selective suppression of KATP and found that LoF in skeletal muscle, specifically, underlies myopathy. In isolated muscle, SUR2 LoF results in abnormal generation of unstimulated forces, potentially explaining painful spasms in AIMS. We sought to determine whether excessive Ca2+ influx through CaV 1.1 channels was responsible for myopathology but found that the Ca2+ channel blocker verapamil unexpectedly resulted in premature death of AIMS mice and that rendering CaV 1.1 channels nonpermeable by mutation failed to reverse pathology; results which caution against the use of calcium channel blockers in AIMS.
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Affiliation(s)
- Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases, and Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMOUSA
- Center for Advanced Biotechnology and Medicine, and Departments of Pharmacology and Medicine, Robert Wood Johnson Medical SchoolRutgers UniversityPiscatawayNJUSA
| | - Maya A Mukadam
- Center for the Investigation of Membrane Excitability Diseases, and Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMOUSA
| | - Jacob Roeglin
- Center for the Investigation of Membrane Excitability Diseases, and Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMOUSA
| | - Robert C Tryon
- Center for the Investigation of Membrane Excitability Diseases, and Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMOUSA
| | - Manfred Grabner
- Department of PharmacologyMedical University of InnsbruckInnsbruckAustria
| | - Anamika Dayal
- Department of PharmacologyMedical University of InnsbruckInnsbruckAustria
| | - Gretchen A Meyer
- Program in Physical Therapy, Departments of Orthopaedic Surgery, Neurology and Biomedical EngineeringWashington University School of MedicineSt. LouisMOUSA
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases, and Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMOUSA
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8
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Mattiucci A, Girolomoni G, Cassina M, Zoller T, Antoniazzi F, Schena D. Cantú syndrome: A new case and evolution of clinical conditions during first 2-year follow-up. Clin Case Rep 2023; 11:e6928. [PMID: 36873080 PMCID: PMC9979969 DOI: 10.1002/ccr3.6928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/28/2022] [Accepted: 01/19/2023] [Indexed: 03/06/2023] Open
Abstract
Cantú syndrome, or hypertrichotic osteochondrodysplasia, is a rare autosomal dominant disease characterized by congenital hypertrichosis, characteristic dysmorphisms, skeletal abnormalities and cardiomegaly. We report on a 7-year-old girl with congenital generalized hypertrichosis, coarse facial appearance and cardiac involvement, with a de novo heterozygous mutation (c.3461G > A) in the ABCC9 gene. During the annual cardiac follow-up at the age of nine the echocardiogram showed mild left ventricular dilatation in consideration of which she started ramipril treatment. The progression of the clinical manifestations of Cantú syndrome highlights the relevance of an early diagnosis, including genetic analysis, and a multidisciplinary approach with long-term follow-up.
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Affiliation(s)
- Alessandra Mattiucci
- Section of Dermatology and Venereology, Department of MedicineUniversity of VeronaVeronaItaly
| | - Giampiero Girolomoni
- Section of Dermatology and Venereology, Department of MedicineUniversity of VeronaVeronaItaly
| | - Matteo Cassina
- Clinical Genetics Unit, Department of Women's and Children's HealthUniversity of PadovaPadovaItaly
| | - Thomas Zoller
- Pediatric Clinic, Department Surgical Sciences, Dentistry, Gynecology and PediatricsUniversity of VeronaVeronaItaly
| | - Franco Antoniazzi
- Pediatric Clinic, Department Surgical Sciences, Dentistry, Gynecology and PediatricsUniversity of VeronaVeronaItaly
| | - Donatella Schena
- Section of Dermatology and Venereology, Department of MedicineUniversity of VeronaVeronaItaly
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9
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Nam YW, Downey M, Rahman MA, Cui M, Zhang M. Channelopathy of small- and intermediate-conductance Ca 2+-activated K + channels. Acta Pharmacol Sin 2023; 44:259-267. [PMID: 35715699 PMCID: PMC9889811 DOI: 10.1038/s41401-022-00935-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 05/31/2022] [Indexed: 02/04/2023] Open
Abstract
Small- and intermediate-conductance Ca2+-activated K+ (KCa2.x/KCa3.1 also called SK/IK) channels are gated exclusively by intracellular Ca2+. The Ca2+ binding protein calmodulin confers sub-micromolar Ca2+ sensitivity to the channel-calmodulin complex. The calmodulin C-lobe is constitutively associated with the proximal C-terminus of the channel. Interactions between calmodulin N-lobe and the channel S4-S5 linker are Ca2+-dependent, which subsequently trigger conformational changes in the channel pore and open the gate. KCNN genes encode four subtypes, including KCNN1 for KCa2.1 (SK1), KCNN2 for KCa2.2 (SK2), KCNN3 for KCa2.3 (SK3), and KCNN4 for KCa3.1 (IK). The three KCa2.x channel subtypes are expressed in the central nervous system and the heart. The KCa3.1 subtype is expressed in the erythrocytes and the lymphocytes, among other peripheral tissues. The impact of dysfunctional KCa2.x/KCa3.1 channels on human health has not been well documented. Human loss-of-function KCa2.2 mutations have been linked with neurodevelopmental disorders. Human gain-of-function mutations that increase the apparent Ca2+ sensitivity of KCa2.3 and KCa3.1 channels have been associated with Zimmermann-Laband syndrome and hereditary xerocytosis, respectively. This review article discusses the physiological significance of KCa2.x/KCa3.1 channels, the pathophysiology of the diseases linked with KCa2.x/KCa3.1 mutations, the structure-function relationship of the mutant KCa2.x/KCa3.1 channels, and potential pharmacological therapeutics for the KCa2.x/KCa3.1 channelopathy.
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Affiliation(s)
- Young-Woo Nam
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Myles Downey
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Mohammad Asikur Rahman
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA
| | - Meng Cui
- Department of Pharmaceutical Sciences, Northeastern University School of Pharmacy, Boston, MA, 02115, USA
| | - Miao Zhang
- Department of Biomedical and Pharmaceutical Sciences, Chapman University School of Pharmacy, Irvine, CA, 92618, USA.
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10
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Gao J, McClenaghan C, Christiaans I, Alders M, van Duinen K, van Haelst MM, van Haaften G, Nichols CG. Lymphedema as first clinical presentation of Cantu Syndrome: reversed phenotyping after identification of gain-of-function variant in ABCC9. Eur J Hum Genet 2023; 31:188-194. [PMID: 36336713 PMCID: PMC9905590 DOI: 10.1038/s41431-022-01210-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 08/16/2022] [Accepted: 09/30/2022] [Indexed: 11/09/2022] Open
Abstract
Cantu Syndrome (CS), [OMIM #239850] is characterized by hypertrichosis, osteochondrodysplasia, and cardiomegaly. CS is caused by gain-of-function (GOF) variants in the KCNJ8 or ABCC9 genes that encode pore-forming Kir6.1 and regulatory SUR2 subunits of ATP-sensitive potassium (KATP) channels. Many subjects with CS also present with the complication of lymphedema. A previously uncharacterized, heterozygous ABCC9 variant, p.(Leu1055_Glu1058delinsPro), termed indel1055, was identified in an individual diagnosed with idiopathic lymphedema. The variant was introduced into the equivalent position of rat SUR2A, and inside-out patches were used to characterize the KATP channels formed by Kir6.2 and WT or mutant SUR2A subunits coexpressed in Cosm6 cells. The indel1055 variant causes gain-of-function of the channel, with an increase of the IC50 for ATP inhibition compared to WT. Retrospective consideration of this individual reveals clear features of Cantu Syndrome. An additional heterozygous ABCC9 variant, p.(Ile419Thr), was identified in a second individual diagnosed with lymphedema. In this case, there were no additional features consistent with CS, and the properties of p.(Ile416Thr) (the corresponding mutation in rat SUR2A)--containing channels were not different from WT. This proof-of-principle study shows that idiopathic lymphedema may actually be a first presentation of otherwise unrecognized Cantu Syndrome, but molecular phenotyping of identified variants is necessary to confirm relevance.
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Affiliation(s)
- Jian Gao
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St. Louis, St. Louis, MO, USA
| | - Conor McClenaghan
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St. Louis, St. Louis, MO, USA
| | - Imke Christiaans
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Marielle Alders
- University of Amsterdam, Department of Human Genetics, Meibergdreef 9, Amsterdam, The Netherlands
| | - Kirsten van Duinen
- Department of Dermatology, Nij Smellinghe Hospital, Drachten, The Netherlands
| | - Mieke M van Haelst
- University of Amsterdam, Department of Human Genetics, Meibergdreef 9, Amsterdam, The Netherlands.
- Departments of Pediatrics, Amsterdam University Medical Centers, Amsterdam, The Netherlands.
- Emma Center for Personalized Medicine, Amsterdam University Medical Centers, Amsterdam, The Netherlands.
| | - Gijs van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Colin G Nichols
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St. Louis, St. Louis, MO, USA.
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11
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Abstract
Ubiquitously expressed throughout the body, ATP-sensitive potassium (KATP) channels couple cellular metabolism to electrical activity in multiple tissues; their unique assembly as four Kir6 pore-forming subunits and four sulfonylurea receptor (SUR) subunits has resulted in a large armory of selective channel opener and inhibitor drugs. The spectrum of monogenic pathologies that result from gain- or loss-of-function mutations in these channels, and the potential for therapeutic correction of these pathologies, is now clear. However, while available drugs can be effective treatments for specific pathologies, cross-reactivity with the other Kir6 or SUR subfamily members can result in drug-induced versions of each pathology and may limit therapeutic usefulness. This review discusses the background to KATP channel physiology, pathology, and pharmacology and considers the potential for more specific or effective therapeutic agents.
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Affiliation(s)
- Colin G. Nichols
- Center for the Investigation of Membrane Excitability Diseases and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
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12
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Singh GK, McClenaghan C, Aggarwal M, Gu H, Remedi MS, Grange DK, Nichols CG. A Unique High-Output Cardiac Hypertrophy Phenotype Arising From Low Systemic Vascular Resistance in Cantu Syndrome. J Am Heart Assoc 2022; 11:e027363. [PMID: 36515236 PMCID: PMC9798820 DOI: 10.1161/jaha.122.027363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 10/25/2022] [Indexed: 12/15/2022]
Abstract
Background Cardiomegaly caused by left ventricular hypertrophy is a risk factor for development of congestive heart failure, classically associated with decreased systolic and/or diastolic ventricular function. Less attention has been given to the phenotype of left ventricular hypertrophy with enhanced ventricular function and increased cardiac output, which is potentially associated with high-output heart failure. Lack of recognition may pose diagnostic ambiguity and management complexities. Methods and Results We sought to systematically characterize high-output cardiac hypertrophy in subjects with Cantu syndrome (CS), caused by gain-of-function variants in ABCC9, which encodes cardiovascular KATP (ATP-sensitive potassium) channel subunits. We studied the cardiovascular phenotype longitudinally in 31 subjects with CS with confirmed ABCC9 variants (median [interquartile range] age 8 years [3-32 years], body mass index 19.9 [16.5-22.9], 16 male subjects). Subjects with CS presented with significant left ventricular hypertrophy (left ventricular mass index 86.7 [57.7-103.0] g/m2 in CS, n=30; 26.6 [24.1-32.8] g/m2 in controls, n=17; P<0.0001) and low blood pressure (systolic 94.5 [90-103] mm Hg in CS, n=17; 109 [98-115] mm Hg in controls, n=17; P=0.0301; diastolic 60 [56-66] mm Hg in CS, n=17; 69 [65-72] mm Hg in control, n=17; P=0.0063). Most (21/31) subjects with CS exhibited eccentric hypertrophy with normal left ventricular wall thickness. Congestive heart failure symptoms were evident in 4 of the 5 subjects with CS aged >40 years on long-term follow-up. Conclusions The data define the natural history of high-output cardiac hypertrophy resulting from decreased systemic vascular resistance in subjects with CS, a defining population for long-term consequences of high-output hypertrophy caused by low systemic vascular resistance, and the potential for progression to high-output heart failure.
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Affiliation(s)
- Gautam K. Singh
- Division of Cardiology, Department of PediatricsWashington University School of MedicineSt. LouisMO
- Center for the Investigation of Membrane Excitability Diseases (CIMED)Washington University School of MedicineSt. LouisMO
| | - Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases (CIMED)Washington University School of MedicineSt. LouisMO
- Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMO
| | - Manish Aggarwal
- Division of Cardiology, Department of PediatricsWashington University School of MedicineSt. LouisMO
| | - Hongjie Gu
- Division of StatisticsWashington University School of MedicineSt. LouisMO
| | - Maria S. Remedi
- Center for the Investigation of Membrane Excitability Diseases (CIMED)Washington University School of MedicineSt. LouisMO
- Department of Medicine, Division of EndocrinologyWashington University School of MedicineSt. LouisMO
| | - Dorothy K. Grange
- Center for the Investigation of Membrane Excitability Diseases (CIMED)Washington University School of MedicineSt. LouisMO
- Department of Pediatrics, Division of GeneticsWashington University School of MedicineSt. LouisMO
| | - Colin G. Nichols
- Center for the Investigation of Membrane Excitability Diseases (CIMED)Washington University School of MedicineSt. LouisMO
- Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMO
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13
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Crespo-García T, Rubio-Alarcón M, Cámara-Checa A, Dago M, Rapún J, Nieto-Marín P, Marín M, Cebrián J, Tamargo J, Delpón E, Caballero R. A Cantú syndrome mutation produces dual effects on KATP channels by disrupting ankyrin B regulation. J Gen Physiol 2022; 155:213613. [PMID: 36287534 PMCID: PMC9614705 DOI: 10.1085/jgp.202112995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 09/09/2022] [Accepted: 10/04/2022] [Indexed: 02/01/2023] Open
Abstract
ATP-sensitive potassium (KATP) channels composed of Kir6.x and sulfonylurea receptor (SURs) subunits couple cellular metabolism to electrical activity. Cantú syndrome (CS) is a rare disease caused by mutations in the genes encoding Kir6.1 (KCNJ8) and SUR2A (ABCC9) that produce KATP channel hyperactivity due to a reduced channel block by physiological ATP concentrations. We functionally characterized the p.S1054Y SUR2A mutation identified in two CS carriers, who exhibited a mild phenotype although the mutation was predicted as highly pathogenic. We recorded macroscopic and single-channel currents in CHO and HEK-293 cells and measured the membrane expression of the channel subunits by biotinylation assays in HEK-293 cells. The mutation increased basal whole-cell current density and at the single-channel level, it augmented opening frequency, slope conductance, and open probability (Po), and promoted the appearance of multiple conductance levels. p.S1054Y also reduced Kir6.2 and SUR2A expression specifically at the membrane. Overexpression of ankyrin B (AnkB) prevented these gain- and loss-of-function effects, as well as the p.S1054Y-induced reduction of ATP inhibition of currents measured in inside-out macropatches. Yeast two-hybrid assays suggested that SUR2A WT and AnkB interact, while p.S1054Y interaction with AnkB is decreased. The p.E322K Kir6.2 mutation, which prevents AnkB binding to Kir6.2, produced similar biophysical alterations than p.S1054Y. Our results are the first demonstration of a CS mutation whose functional consequences involve the disruption of AnkB effects on KATP channels providing a novel mechanism by which CS mutations can reduce ATP block. Furthermore, they may help explain the mild phenotype associated with this mutation.
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Affiliation(s)
- Teresa Crespo-García
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Marcos Rubio-Alarcón
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Anabel Cámara-Checa
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - María Dago
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Josu Rapún
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Paloma Nieto-Marín
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - María Marín
- Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Jorge Cebrián
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Juan Tamargo
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
| | - Eva Delpón
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain,Correspondence to Eva Delpón:
| | - Ricardo Caballero
- Department of Pharmacology and Toxicology, School of Medicine, Universidad Complutense de Madrid, Instituto de Investigación Gregorio Marañón, Madrid, Spain,Centro de Investigación Biomédica en Red Enfermedades Cardiovasculares, Madrid, Spain
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14
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McClenaghan C, Nichols CG. Kir6.1 and SUR2B in Cantú syndrome. Am J Physiol Cell Physiol 2022; 323:C920-C935. [PMID: 35876283 PMCID: PMC9467476 DOI: 10.1152/ajpcell.00154.2022] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/07/2022] [Accepted: 07/07/2022] [Indexed: 12/25/2022]
Abstract
Kir6.1 and SUR2 are subunits of ATP-sensitive potassium (KATP) channels expressed in a wide range of tissues. Extensive study has implicated roles of these channel subunits in diverse physiological functions. Together they generate the predominant KATP conductance in vascular smooth muscle and are the target of vasodilatory drugs. Roles for Kir6.1/SUR2 dysfunction in disease have been suggested based on studies of animal models and human genetic discoveries. In recent years, it has become clear that gain-of-function (GoF) mutations in both genes result in Cantú syndrome (CS)-a complex, multisystem disorder. There is currently no targeted therapy for CS, but studies of mouse models of the disease reveal that pharmacological reversibility of cardiovascular and gastrointestinal pathologies can be achieved by administration of the KATP channel inhibitor, glibenclamide. Here we review the function, structure, and physiological and pathological roles of Kir6.1/SUR2B channels, with a focus on CS. Recent studies have led to much improved understanding of the underlying pathologies and the potential for treatment, but important questions remain: Can the study of genetically defined CS reveal new insights into Kir6.1/SUR2 function? Do these reveal new pathophysiological mechanisms that may be important in more common diseases? And is our pharmacological armory adequately stocked?
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Affiliation(s)
- Conor McClenaghan
- Department of Cell Biology and Physiology, Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St. Louis, Missouri
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St. Louis, Missouri
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15
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Abstract
Heart disease is the leading cause of death worldwide. Despite decades of research, most heart pathologies have limited treatments, and often the only curative approach is heart transplantation. Thus, there is an urgent need to develop new therapeutic approaches for treating cardiac diseases. Animal models that reproduce the human pathophysiology are essential to uncovering the biology of diseases and discovering therapies. Traditionally, mammals have been used as models of cardiac disease, but the cost of generating and maintaining new models is exorbitant, and the studies have very low throughput. In the last decade, the zebrafish has emerged as a tractable model for cardiac diseases, owing to several characteristics that made this animal popular among developmental biologists. Zebrafish fertilization and development are external; embryos can be obtained in high numbers, are cheap and easy to maintain, and can be manipulated to create new genetic models. Moreover, zebrafish exhibit an exceptional ability to regenerate their heart after injury. This review summarizes 25 years of research using the zebrafish to study the heart, from the classical forward screenings to the contemporary methods to model mutations found in patients with cardiac disease. We discuss the advantages and limitations of this model organism and introduce the experimental approaches exploited in zebrafish, including forward and reverse genetics and chemical screenings. Last, we review the models used to induce cardiac injury and essential ideas derived from studying natural regeneration. Studies using zebrafish have the potential to accelerate the discovery of new strategies to treat cardiac diseases.
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Affiliation(s)
- Juan Manuel González-Rosa
- Cardiovascular Research Center, Massachusetts General Hospital Research Institute, Harvard Medical School, Charlestown, MA
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16
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Marques P, Korbonits M. Approach to the Patient With Pseudoacromegaly. J Clin Endocrinol Metab 2022; 107:1767-1788. [PMID: 34792134 DOI: 10.1210/clinem/dgab789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Indexed: 11/19/2022]
Abstract
Pseudoacromegaly encompasses a heterogeneous group of conditions in which patients have clinical features of acromegaly or gigantism, but no excess of GH or IGF-1. Acromegaloid physical features or accelerated growth in a patient may prompt referral to endocrinologists. Because pseudoacromegaly conditions are rare and heterogeneous, often with overlapping clinical features, the underlying diagnosis may be challenging to establish. As many of these have a genetic origin, such as pachydermoperiostosis, Sotos syndrome, Weaver syndrome, or Cantú syndrome, collaboration is key with clinical geneticists in the diagnosis of these patients. Although rare, awareness of these uncommon conditions and their characteristic features will help their timely recognition.
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Affiliation(s)
- Pedro Marques
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ London, UK
- Endocrinology Department, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte, Lisboa, Portugal
| | - Márta Korbonits
- Centre for Endocrinology, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, EC1M 6BQ London, UK
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17
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Apuril Velgara ES, Mariani M, Torella A, Musacchia F, Nigro V, Selicorni A. Cantù syndrome: Report of a patient with a novel variant in KCNJ8 and revision of literature. Am J Med Genet A 2022; 188:1661-1666. [PMID: 35243770 DOI: 10.1002/ajmg.a.62710] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 10/10/2021] [Accepted: 01/28/2022] [Indexed: 01/26/2023]
Abstract
Cantù syndrome (CS) is a rare multisystemic disorder, characterized by congenital hypertrichosis, macrocephaly, facial dysmorphisms, cardiomegaly, vascular, and skeletal anomalies. From the cognitive point of view, most of the patients show a mild speech delay and a few of them present intellectual disability and learning difficulties. To date, most CS-reported cases are caused by heterozygous ABCC9 gene mutations. Only three patients with CS and heterozygous KCNJ8 gene variants have been reported. The authors here present the fourth case of CS with a variant in KCNJ8 in a 6-month-old baby. Diagnosis was reached through Trio-Whole Exome analysis that revealed a de novo missense variant in KCNJ8.
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Affiliation(s)
- Erika Solansh Apuril Velgara
- Department of Pediatric, Mariani Foundation Center for Fragile Child ASST-Lariana, Sant'Anna Hospital, San Fermo della Battaglia (Como), Italy
| | - Milena Mariani
- Department of Pediatric, Mariani Foundation Center for Fragile Child ASST-Lariana, Sant'Anna Hospital, San Fermo della Battaglia (Como), Italy
| | - Annalaura Torella
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy.,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | | | | | - Vincenzo Nigro
- Department of Precision Medicine, University "Luigi Vanvitelli", Naples, Italy.,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Angelo Selicorni
- Department of Pediatric, Mariani Foundation Center for Fragile Child ASST-Lariana, Sant'Anna Hospital, San Fermo della Battaglia (Como), Italy
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18
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Singareddy SS, Roessler HI, McClenaghan C, Ikle JM, Tryon RC, van Haaften G, Nichols CG. ATP-sensitive potassium channels in zebrafish cardiac and vascular smooth muscle. J Physiol 2021; 600:299-312. [PMID: 34820842 DOI: 10.1113/jp282157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/18/2021] [Indexed: 12/12/2022] Open
Abstract
ATP-sensitive potassium channels (KATP channels) are hetero-octameric nucleotide-gated ion channels that couple cellular metabolism to excitability in various tissues. In the heart, KATP channels are activated during ischaemia and potentially during adrenergic stimulation. In the vasculature, they are normally active at a low level, reducing vascular tone, but the ubiquitous nature of these channels leads to complex and poorly understood channelopathies as a result of gain- or loss-of-function mutations. Zebrafish (ZF) models of these channelopathies may provide insights to the link between molecular dysfunction and complex pathophysiology, but this requires understanding the tissue dependence of channel activity and subunit specificity. Thus far, direct analysis of ZF KATP expression and functional properties has only been performed in pancreatic β-cells. Using a comprehensive combination of genetically modified fish, electrophysiology and gene expression analysis, we demonstrate that ZF cardiac myocytes (CM) and vascular smooth muscle (VSM) express functional KATP channels of similar subunit composition, structure and metabolic sensitivity to their mammalian counterparts. However, in contrast to mammalian cardiovascular KATP channels, ZF channels are insensitive to potassium channel opener drugs (pinacidil, minoxidil) in both chambers of the heart and in VSM. The results provide a first characterization of the molecular properties of fish KATP channels and validate the use of such genetically modified fish as models of human Cantú syndrome and ABCC9-related Intellectual Disability and Myopathy syndrome. KEY POINTS: Zebrafish cardiac myocytes (CM) and vascular smooth muscle (VSM) express functional KATP channels of similar subunit composition, structure and metabolic sensitivity to their mammalian counterparts. In contrast to mammalian cardiovascular KATP channels, zebrafish channels are insensitive to potassium channel opener drugs (pinacidil, minoxidil) in both chambers of the heart and in VSM. We provide a first characterization of the molecular properties of fish KATP channels and validate the use of such genetically modified fish as models of human Cantú syndrome and ABCC9-related Intellectual Disability and Myopathy syndrome.
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Affiliation(s)
- Soma S Singareddy
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St Louis, St Louis, MO, USA
| | - Helen I Roessler
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Conor McClenaghan
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St Louis, St Louis, MO, USA
| | - Jennifer M Ikle
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St Louis, St Louis, MO, USA
| | - Robert C Tryon
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St Louis, St Louis, MO, USA
| | - Gijs van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Colin G Nichols
- Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability Diseases, Washington University in St Louis, St Louis, MO, USA
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19
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Tran TNA, Phan HN, Vu HA, Nguyen HT. Diverse clinical manifestations of Cantú syndrome: The first case series in Vietnam. Am J Med Genet A 2021; 188:377-381. [PMID: 34453476 DOI: 10.1002/ajmg.a.62477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/02/2021] [Accepted: 08/13/2021] [Indexed: 11/08/2022]
Abstract
Cantú syndrome (CS) is an extremely rare autosomal dominant hereditary disease characterized by congenital hypertrichosis, distinct coarse facial features, cardiac defects, and other abnormalities in the skeletal and neurological systems. At present, cases with pathognomonic clinical manifestations are increasingly confirmed by genetic analysis. Two causative genes for CS are the well-known ABCC9 and the more rarely reported KCNJ8. Here, we report three Vietnamese children with CS, confirmed through genetic testing, presenting de novo ABCC9 mutations. The patients shared some common clinical manifestations, including congenital hypertrichosis, distinctive facial features, and a history of polyhydramnios during pregnancy. Concerning the various cardiac and neurological problems in the lifetime of patients with CS, an accurate diagnosis and appropriate management, especially genetic counseling, should be clinically applied in CS. Thus, our findings might modestly contribute to the global CS data, providing practical insights into CS manifestations.
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Affiliation(s)
- Tu Nguyen Anh Tran
- Ho Chi Minh City Hospital of Dermato-Venereology, Ho Chi Minh City, Vietnam
| | - Huy Ngoc Phan
- Ho Chi Minh City Hospital of Dermato-Venereology, Ho Chi Minh City, Vietnam
| | - Hoang Anh Vu
- Center for Molecular Biomedicine, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Vietnam
| | - Hao Trong Nguyen
- Ho Chi Minh City Hospital of Dermato-Venereology, Ho Chi Minh City, Vietnam
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20
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Roessler HI, van der Heuvel LM, Shields K, Guilliams KP, Knoers NVAM, van Haaften G, Grange DK, van Haelst MM. Behavioral and cognitive functioning in individuals with Cantú syndrome. Am J Med Genet A 2021; 185:2434-2444. [PMID: 34056838 DOI: 10.1002/ajmg.a.62348] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 04/20/2021] [Accepted: 05/07/2021] [Indexed: 11/07/2022]
Abstract
Cantú syndrome (CS) is caused by pathogenic variants in ABCC9 and KCNJ8 encoding the regulatory and pore-forming subunits of ATP-sensitive potassium (KATP ) channels. CS is characterized by congenital hypertrichosis, distinctive facial features, peripheral edema, and cardiac and neurodevelopmental abnormalities. Behavioral and cognitive issues have been self-reported by some CS individuals, but results of formal standardized investigations have not been published. To assess the cognitive profile, social functioning, and psychiatric symptoms in a large group of CS subjects systematically in a cross-sectional manner, we invited 35 individuals (1-69 years) with confirmed ABCC9 variants and their relatives to complete various commonly applied standardized age-related questionnaires, including the Kaufman brief intelligence test 2, the social responsiveness scale-2, and the Achenbach system of empirically based assessment. The majority of CS individuals demonstrated average verbal and nonverbal intelligence compared to the general population. Fifteen percent of cases showed social functioning strongly associated with a clinical diagnosis of autism spectrum disorder. Both externalizing and internalizing problems were also present in this cohort. In particular, anxiety, anxiety or attention deficit hyperactivity disorder, and autism spectrum behaviors were predominantly observed in the younger subjects in the cohort (≥25%), but this percentage decreased markedly in adults.
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Affiliation(s)
- Helen I Roessler
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Lieke M van der Heuvel
- Department of Clinical Genetics, Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - Kathleen Shields
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Kristin P Guilliams
- Division of Pediatric Neurology, Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, USA
- Division of Pediatric Critical Care, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Nine V A M Knoers
- Department of Genetics, University Medical Center Groningen, Groningen, The Netherlands
| | - Gijs van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Dorothy K Grange
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
- Center for the Investigation of Membrane Excitability Diseases (CIMED), St. Louis, Missouri, USA
| | - Mieke M van Haelst
- Department of Clinical Genetics, Amsterdam University Medical Centers, Amsterdam, The Netherlands
- Department of Clinical Genetics, VU Medical Center, Amsterdam University Medical Centers, Amsterdam, The Netherlands
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21
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Mondéjar-Parreño G, Cogolludo A, Perez-Vizcaino F. Potassium (K +) channels in the pulmonary vasculature: Implications in pulmonary hypertension Physiological, pathophysiological and pharmacological regulation. Pharmacol Ther 2021; 225:107835. [PMID: 33744261 DOI: 10.1016/j.pharmthera.2021.107835] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/26/2021] [Accepted: 03/02/2021] [Indexed: 02/06/2023]
Abstract
The large K+ channel functional diversity in the pulmonary vasculature results from the multitude of genes expressed encoding K+ channels, alternative RNA splicing, the post-transcriptional modifications, the presence of homomeric or heteromeric assemblies of the pore-forming α-subunits and the existence of accessory β-subunits modulating the functional properties of the channel. K+ channels can also be regulated at multiple levels by different factors controlling channel activity, trafficking, recycling and degradation. The activity of these channels is the primary determinant of membrane potential (Em) in pulmonary artery smooth muscle cells (PASMC), providing an essential regulatory mechanism to dilate or contract pulmonary arteries (PA). K+ channels are also expressed in pulmonary artery endothelial cells (PAEC) where they control resting Em, Ca2+ entry and the production of different vasoactive factors. The activity of K+ channels is also important in regulating the population and phenotype of PASMC in the pulmonary vasculature, since they are involved in cell apoptosis, survival and proliferation. Notably, K+ channels play a major role in the development of pulmonary hypertension (PH). Impaired K+ channel activity in PH results from: 1) loss of function mutations, 2) downregulation of its expression, which involves transcription factors and microRNAs, or 3) decreased channel current as a result of increased vasoactive factors (e.g., hypoxia, 5-HT, endothelin-1 or thromboxane), exposure to drugs with channel-blocking properties, or by a reduction in factors that positively regulate K+ channel activity (e.g., NO and prostacyclin). Restoring K+ channel expression, its intracellular trafficking and the channel activity is an attractive therapeutic strategy in PH.
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Affiliation(s)
- Gema Mondéjar-Parreño
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain; Ciber Enfermedades Respiratorias (CIBERES), Spain
| | - Angel Cogolludo
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain; Ciber Enfermedades Respiratorias (CIBERES), Spain
| | - Francisco Perez-Vizcaino
- Department of Pharmacology and Toxicology, School of Medicine, University Complutense of Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain; Ciber Enfermedades Respiratorias (CIBERES), Spain.
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22
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Zhang H, Hanson A, de Almeida TS, Emfinger C, McClenaghan C, Harter T, Yan Z, Cooper PE, Brown GS, Arakel EC, Mecham RP, Kovacs A, Halabi CM, Schwappach B, Remedi MS, Nichols CG. Complex consequences of Cantu syndrome SUR2 variant R1154Q in genetically modified mice. JCI Insight 2021; 6:145934. [PMID: 33529173 PMCID: PMC8021106 DOI: 10.1172/jci.insight.145934] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/27/2021] [Indexed: 01/10/2023] Open
Abstract
Cantu syndrome (CS) is caused by gain-of-function (GOF) mutations in pore-forming (Kir6.1, KCNJ8) and accessory (SUR2, ABCC9) ATP-sensitive potassium (KATP) channel subunits, the most common mutations being SUR2[R1154Q] and SUR2[R1154W], carried by approximately 30% of patients. We used CRISPR/Cas9 genome engineering to introduce the equivalent of the human SUR2[R1154Q] mutation into the mouse ABCC9 gene. Along with minimal CS disease features, R1154Q cardiomyocytes and vascular smooth muscle showed much lower KATP current density and pinacidil activation than WT cells. Almost complete loss of SUR2-dependent protein and KATP in homozygous R1154Q ventricles revealed underlying diazoxide-sensitive SUR1-dependent KATP channel activity. Surprisingly, sequencing of SUR2 cDNA revealed 2 distinct transcripts, one encoding full-length SUR2 protein; and the other with an in-frame deletion of 93 bases (corresponding to 31 amino acids encoded by exon 28) that was present in approximately 40% and approximately 90% of transcripts from hetero- and homozygous R1154Q tissues, respectively. Recombinant expression of SUR2A protein lacking exon 28 resulted in nonfunctional channels. CS tissue from SUR2[R1154Q] mice and human induced pluripotent stem cell-derived (hiPSC-derived) cardiomyocytes showed only full-length SUR2 transcripts, although further studies will be required in order to fully test whether SUR2[R1154Q] or other CS mutations might result in aberrant splicing and variable expressivity of disease features in human CS.
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Affiliation(s)
- Haixia Zhang
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Alex Hanson
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Tobias Scherf de Almeida
- Department of Molecular Biology, Center for Biochemistry and Molecular Cell Biology, Heart Research Center Göttingen, University Medicine Göttingen, Göttingen, Germany
| | - Christopher Emfinger
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Theresa Harter
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Zihan Yan
- Center for the Investigation of Membrane Excitability Diseases and.,DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Göttingen, Germany.,Department of Medicine, Division of Endocrinology, Metabolism and Lipid Research
| | - Paige E Cooper
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - G Schuyler Brown
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Eric C Arakel
- Department of Molecular Biology, Center for Biochemistry and Molecular Cell Biology, Heart Research Center Göttingen, University Medicine Göttingen, Göttingen, Germany
| | - Robert P Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | | | - Carmen M Halabi
- Department of Pediatrics, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
| | - Blanche Schwappach
- Department of Molecular Biology, Center for Biochemistry and Molecular Cell Biology, Heart Research Center Göttingen, University Medicine Göttingen, Göttingen, Germany
| | - Maria S Remedi
- Center for the Investigation of Membrane Excitability Diseases and.,DZHK (German Center for Cardiovascular Research), Partner Site Göttingen, Göttingen, Germany
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases and.,Department of Cell Biology and Physiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
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23
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Srivastava P, Kane A, Harrison C, Levin M. A Meta-Analysis of Bioelectric Data in Cancer, Embryogenesis, and Regeneration. Bioelectricity 2021; 3:42-67. [PMID: 34476377 DOI: 10.1089/bioe.2019.0034] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Developmental bioelectricity is the study of the endogenous role of bioelectrical signaling in all cell types. Resting potentials and other aspects of ionic cell physiology are known to be important regulatory parameters in embryogenesis, regeneration, and cancer. However, relevant quantitative measurement and genetic phenotyping data are distributed throughout wide-ranging literature, hampering experimental design and hypothesis generation. Here, we analyze published studies on bioelectrics and transcriptomic and genomic/phenotypic databases to provide a novel synthesis of what is known in three important aspects of bioelectrics research. First, we provide a comprehensive list of channelopathies-ion channel and pump gene mutations-in a range of important model systems with developmental patterning phenotypes, illustrating the breadth of channel types, tissues, and phyla (including man) in which bioelectric signaling is a critical endogenous aspect of embryogenesis. Second, we perform a novel bioinformatic analysis of transcriptomic data during regeneration in diverse taxa that reveals an electrogenic protein to be the one common factor specifically expressed in regeneration blastemas across Kingdoms. Finally, we analyze data on distinct Vmem signatures in normal and cancer cells, revealing a specific bioelectrical signature corresponding to some types of malignancies. These analyses shed light on fundamental questions in developmental bioelectricity and suggest new avenues for research in this exciting field.
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Affiliation(s)
- Pranjal Srivastava
- Rye High School, Rye, New York, USA; Current Affiliation: College of Chemistry, University of California, Berkeley, Berkeley, California, USA
| | - Anna Kane
- Department of Biology, Allen Discovery Center, Tufts University, Medford, Massachusetts, USA
| | - Christina Harrison
- Department of Biology, Allen Discovery Center, Tufts University, Medford, Massachusetts, USA
| | - Michael Levin
- Department of Biology, Allen Discovery Center, Tufts University, Medford, Massachusetts, USA
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24
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Mani I. Genome editing in cardiovascular diseases. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 181:289-308. [PMID: 34127197 DOI: 10.1016/bs.pmbts.2021.01.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Genetic modification at the molecular level in somatic cells, germline, and animal models requires for different purposes, such as introducing desired mutation, deletion of alleles, and insertion of novel genes in the genome. Various genome-editing tools are available to accomplish these alterations, such as zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated (Cas) system. CRISPR-Cas system is an emerging technology, which is being used in biological and medical sciences, including in the cardiovascular field. It assists to identify the mechanism of various cardiovascular disease occurrence, such as hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and arrhythmogenic cardiomyopathy (ACM). Furthermore, it has been advantages to edit various genes simultaneously and can also be used to treat and prevent several human diseases. This chapter explores the use of the scientific and therapeutic potential of a CRISPR-Cas system to edit the various cardiovascular disease-associated genes to understand the pathways involved in disease progression and treatment.
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Affiliation(s)
- Indra Mani
- Department of Microbiology, Gargi College, University of Delhi, New Delhi, India.
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25
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Gripp KW, Smithson SF, Scurr IJ, Baptista J, Majumdar A, Pierre G, Williams M, Henderson LB, Wentzensen IM, McLaughlin H, Leeuwen L, Simon MEH, van Binsbergen E, Dinulos MBP, Kaplan JD, McRae A, Superti-Furga A, Good JM, Kutsche K. Syndromic disorders caused by gain-of-function variants in KCNH1, KCNK4, and KCNN3-a subgroup of K + channelopathies. Eur J Hum Genet 2021; 29:1384-1395. [PMID: 33594261 PMCID: PMC8440610 DOI: 10.1038/s41431-021-00818-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 01/18/2021] [Accepted: 01/22/2021] [Indexed: 12/13/2022] Open
Abstract
Decreased or increased activity of potassium channels caused by loss-of-function and gain-of-function (GOF) variants in the corresponding genes, respectively, underlies a broad spectrum of human disorders affecting the central nervous system, heart, kidney, and other organs. While the association of epilepsy and intellectual disability (ID) with variants affecting function in genes encoding potassium channels is well known, GOF missense variants in K+ channel encoding genes in individuals with syndromic developmental disorders have only recently been recognized. These syndromic phenotypes include Zimmermann–Laband and Temple–Baraitser syndromes, caused by dominant variants in KCNH1, FHEIG syndrome due to dominant variants in KCNK4, and the clinical picture associated with dominant variants in KCNN3. Here we review the presentation of these individuals, including five newly reported with variants in KCNH1 and three additional individuals with KCNN3 variants, all variants likely affecting function. There is notable overlap in the phenotypic findings of these syndromes associated with dominant KCNN3, KCNH1, and KCNK4 variants, sharing developmental delay and/or ID, coarse facial features, gingival enlargement, distal digital hypoplasia, and hypertrichosis. We suggest to combine the phenotypes and define a new subgroup of potassium channelopathies caused by increased K+ conductance, referred to as syndromic neurodevelopmental K+ channelopathies due to dominant variants in KCNH1, KCNK4, or KCNN3.
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Affiliation(s)
- Karen W Gripp
- Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Sarah F Smithson
- Department of Clinical Genetics, University Hospitals Bristol and Weston, Bristol, UK
| | - Ingrid J Scurr
- Department of Clinical Genetics, University Hospitals Bristol and Weston, Bristol, UK
| | - Julia Baptista
- Exeter Genomics Laboratory, Royal Devon & Exeter NHS Foundation Trust, Exeter, UK.,College of Medicine and Health, University of Exeter, Exeter, UK
| | - Anirban Majumdar
- Department of Paediatric Neurology, Bristol Royal Hospital for Children, Bristol, UK
| | - Germaine Pierre
- Department of Paediatric Metabolic Medicine, Bristol Royal Hospital for Children, Bristol, UK
| | - Maggie Williams
- Bristol Genetics Laboratory, North Bristol NHS Trust, Bristol, UK
| | | | | | | | - Lisette Leeuwen
- Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marleen E H Simon
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Ellen van Binsbergen
- Department of Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Mary Beth P Dinulos
- Section of Genetics and Child Development, Children's Hospital at Dartmouth, Lebanon, NH, USA
| | - Julie D Kaplan
- Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Anne McRae
- Division of Genetics, Birth Defects and Metabolism, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA
| | - Andrea Superti-Furga
- Division of Genetic Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Jean-Marc Good
- Division of Genetic Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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26
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Gao Q, Yang C, Meng L, Wang Z, Chen D, Peng Y, Yang K, Bian Z. Activated KCNQ1 channel promotes fibrogenic response in hereditary gingival fibromatosis via clustering and activation of Ras. J Periodontal Res 2020; 56:471-481. [PMID: 33381870 DOI: 10.1111/jre.12836] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 12/08/2020] [Accepted: 12/11/2020] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND OBJECTIVE Activated potassium channels were found to be strongly correlated with gingival overgrowth (GO) phenotype as we reviewed syndromic hereditary gingival fibromatosis (HGF). Nevertheless, the functional roles of potassium channels in gingival fibrosis or gingival overgrowth remained uncovered. The aim of the present study was to explore the pathogenic role of aberrantly activated potassium channel in Hereditary Gingival Fibromatosis (HGF). METHODS Gingival tissues were collected from 9 HGF patients and 15 normal controls. Expression of KCNQ1 was detected by immunohistochemistry. Gingival fibroblasts were isolated, and outward K+ currents were detected by whole-cell patch-clamp analysis, transmembrane potential was determined by flow cytometry. Normal human gingival fibroblasts (NHGFs) were transfected with KCNQ1 adenovirus or treated with KCNQ1 selective agonist ML277 and antagonist chromanol 293B. Accumulation of Extracellular Matrix (ECM) was measured by Western blotting and Sircol Soluble Collagen Assay. Content of secreted TGF-β1 was measured by ELISA. Active RAS pull-down assay and cell immunofluorescence were utilized to verify RAS activation. RESULTS KCNQ1 was upregulated in gingival tissues derived from HGF patients and HGF gingival fibroblasts presented increased outward K+ currents than NHGFs. Overexpression of KCNQ1, or KCNQ1 agonist ML277, promoted fibrotic responses of NHGFs. TGF-β1 and KCNQ1 channels formed a positive feed-back loop. ML277 generated lateral clustering and activation of Ras on plasma membrane, followed by augmented MAPK/AP-1 signaling pathway output. JNK or ERK1/2 inhibitors suppressed ML277-induced AP-1 and ECM upregulation. CONCLUSION Activation of KCNQ1 potassium channel promoted fibrogenic responses in NHGFs via Ras/MAPK/AP-1 signaling.
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Affiliation(s)
- Qian Gao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Chengcan Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Liuyan Meng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Ziming Wang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Dong Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Yao Peng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Kai Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Zhuan Bian
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
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27
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Aguayo‐Orozco TA, Ríos‐González BE, Castro‐Martínez AG, Ruiz‐Ramírez AV, Figuera LE. Generalized hypertrichosis syndromes in Mexico. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 184:1014-1022. [DOI: 10.1002/ajmg.c.31864] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 11/18/2020] [Accepted: 11/20/2020] [Indexed: 01/09/2023]
Affiliation(s)
- Thania Alejandra Aguayo‐Orozco
- División de Genética, Centro de Investigación Biomédica de Occidente Instituto Mexicano del Seguro Social Guadalajara Jalisco Mexico
- Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud Universidad de Guadalajara Guadalajara Jalisco Mexico
| | | | | | - Andrea Virginia Ruiz‐Ramírez
- División de Genética, Centro de Investigación Biomédica de Occidente Instituto Mexicano del Seguro Social Guadalajara Jalisco Mexico
- Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud Universidad de Guadalajara Guadalajara Jalisco Mexico
| | - Luis E. Figuera
- División de Genética, Centro de Investigación Biomédica de Occidente Instituto Mexicano del Seguro Social Guadalajara Jalisco Mexico
- Doctorado en Genética Humana, Centro Universitario de Ciencias de la Salud Universidad de Guadalajara Guadalajara Jalisco Mexico
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28
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Scala R, Maqoud F, Zizzo N, Mele A, Camerino GM, Zito FA, Ranieri G, McClenaghan C, Harter TM, Nichols CG, Tricarico D. Pathophysiological Consequences of KATP Channel Overactivity and Pharmacological Response to Glibenclamide in Skeletal Muscle of a Murine Model of Cantù Syndrome. Front Pharmacol 2020; 11:604885. [PMID: 33329006 PMCID: PMC7734337 DOI: 10.3389/fphar.2020.604885] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 11/03/2020] [Indexed: 12/11/2022] Open
Abstract
Cantù syndrome (CS) arises from mutations in ABCC9 and KCNJ8 genes that lead to gain of function (GOF) of ATP-sensitive potassium (KATP) channels containing SUR2A and Kir6.1 subunits, respectively, of KATP channels. Pathological consequences of CS have been reported for cardiac and smooth muscle cells but consequences in skeletal muscle are unknown. Children with CS show muscle hypotonia and adult manifest fatigability. We analyzed muscle properties of Kir6.1[V65M] CS mice, by measurements of forelimb strength and ultrasonography of hind-limb muscles, as well as assessing KATP channel properties in native Flexor digitorum brevis (FDB) and Soleus (SOL) fibers by the patch-clamp technique in parallel with histopathological, immunohistochemical and Polymerase Chain Reaction (PCR) analysis. Forelimb strength was lower in Kir6.1wt/VM mice than in WT mice. Also, a significant enhancement of echodensity was observed in hind-limb muscles of Kir6.1wt/VM mice relative to WT, suggesting the presence of fibrous tissue. There was a higher KATP channel current amplitude in Kir6.1wt/VM FDB fibers relative to WT and a reduced response to glibenclamide. The IC50 of glibenclamide to block KATP channels in FDB fibers was 1.3 ± 0.2 × 10−7 M in WT and 1.2 ± 0.1 × 10−6 M in Kir6.1wt/VM mice, respectively; and it was 1.2 ± 0.4 × 10−7 M in SOL WT fibers but not measurable in Kir6.1wt/VM fibers. The sensitivity of the KATP channel to MgATP was not modified in Kir6.1wt/VM fibers. Histopathological/immunohistochemical analysis of SOL revealed degeneration plus regressive-necrotic lesions with regeneration, and up-regulation of Atrogin-1, MuRF1, and BNIP3 mRNA/proteins in Kir6.1wt/VM mice. Kir6.1wt/VM mutation in skeletal muscle leads to changes of the KATP channel response to glibenclamide in FDB and SOL fibers, and it is associated with histopathological and gene expression changes in slow-twitch muscle, suggesting marked atrophy and autophagy.
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Affiliation(s)
- Rosa Scala
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Fatima Maqoud
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Nicola Zizzo
- Section of Veterinary Pathology and Comparative Oncology, Department of Veterinary Medicine, University of Bari "Aldo Moro", Valenzano, Italy
| | - Antonietta Mele
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Giulia Maria Camerino
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Francesco Alfredo Zito
- Interventional and Medical Oncology Unit, Department of Pathology National Cancer Research Centre, IRCCS Istituto Tumori Giovanni Paolo II, Bari, Italy
| | - Girolamo Ranieri
- Interventional and Medical Oncology Unit, Department of Pathology National Cancer Research Centre, IRCCS Istituto Tumori Giovanni Paolo II, Bari, Italy
| | - Conor McClenaghan
- Department of Cell Biology and Physiology, and Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, United States
| | - Theresa M Harter
- Department of Cell Biology and Physiology, and Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, United States
| | - Colin G Nichols
- Department of Cell Biology and Physiology, and Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO, United States
| | - Domenico Tricarico
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari "Aldo Moro", Bari, Italy
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29
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Ding Y, Bu H, Xu X. Modeling Inherited Cardiomyopathies in Adult Zebrafish for Precision Medicine. Front Physiol 2020; 11:599244. [PMID: 33329049 PMCID: PMC7717946 DOI: 10.3389/fphys.2020.599244] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/30/2020] [Indexed: 12/19/2022] Open
Abstract
Cardiomyopathies are a highly heterogeneous group of heart muscle disorders. More than 100 causative genes have been linked to various cardiomyopathies, which explain about half of familial cardiomyopathy cases. More than a dozen candidate therapeutic signaling pathways have been identified; however, precision medicine is not being used to treat the various types of cardiomyopathy because knowledge is lacking for how to tailor treatment plans for different genetic causes. Adult zebrafish (Danio rerio) have a higher throughout than rodents and are an emerging vertebrate model for studying cardiomyopathy. Herein, we review progress in the past decade that has proven the feasibility of this simple vertebrate for modeling inherited cardiomyopathies of distinct etiology, identifying effective therapeutic strategies for a particular type of cardiomyopathy, and discovering new cardiomyopathy genes or new therapeutic strategies via a forward genetic approach. On the basis of this progress, we discuss future research that would benefit from integrating this emerging model, including discovery of remaining causative genes and development of genotype-based therapies. Studies using this efficient vertebrate model are anticipated to significantly accelerate the implementation of precision medicine for inherited cardiomyopathies.
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Affiliation(s)
- Yonghe Ding
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States.,Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States
| | - Haisong Bu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States.,Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States.,Clinical Center for Gene Diagnosis and Therapy, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Xiaolei Xu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, United States.,Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States
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30
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York NW, Parker H, Xie Z, Tyus D, Waheed MA, Yan Z, Grange DK, Remedi MS, England SK, Hu H, Nichols CG. Kir6.1- and SUR2-dependent KATP over-activity disrupts intestinal motility in murine models of Cantu Syndrome. JCI Insight 2020; 5:141443. [PMID: 33170808 PMCID: PMC7714409 DOI: 10.1172/jci.insight.141443] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 10/28/2020] [Indexed: 11/17/2022] Open
Abstract
Cantύ Syndrome (CS), caused by gain-of-function (GOF) mutations in pore-forming (Kir6.1, KCNJ8) and accessory (SUR2, ABCC9) ATP-sensitive potassium (KATP) channel subunit genes, is frequently accompanied by gastrointestinal (GI) dysmotility, and we describe one CS patient who required an implanted intestinal irrigation system for successful stooling. We used gene-modified mice to assess the underlying KATP channel subunits in gut smooth muscle, and to model the consequences of altered KATP channels in CS gut. We show that Kir6.1/SUR2 subunits underlie smooth muscle KATP channels throughout the small intestine and colon. Knock-in mice, carrying human KCNJ8 and ABCC9 CS mutations in the endogenous loci, exhibit reduced intrinsic contractility throughout the intestine, resulting in death when weaned onto solid food in the most severely affected animals. Death is avoided by weaning onto a liquid gel diet, implicating intestinal insufficiency and bowel impaction as the underlying cause, and GI transit is normalized by treatment with the KATP inhibitor glibenclamide. We thus define the molecular basis of intestinal KATP channel activity, the mechanism by which overactivity results in GI insufficiency, and a viable approach to therapy.
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Affiliation(s)
- Nathaniel W York
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
| | - Helen Parker
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
| | - Zili Xie
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - David Tyus
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
| | - Maham A Waheed
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
| | - Zihan Yan
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Dorothy K Grange
- Divison of Clinical Genetics, Washington University School of Medicine, St. Louis, United States of America
| | - Maria S Remedi
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
| | - Sarah K England
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, United States of America
| | - Hongzhen Hu
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, United States of America
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, United States of America
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McClenaghan C, Huang Y, Yan Z, Harter TM, Halabi CM, Chalk R, Kovacs A, van Haaften G, Remedi MS, Nichols CG. Glibenclamide reverses cardiovascular abnormalities of Cantu syndrome driven by KATP channel overactivity. J Clin Invest 2020; 130:1116-1121. [PMID: 31821173 DOI: 10.1172/jci130571] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 12/05/2019] [Indexed: 12/12/2022] Open
Abstract
Cantu syndrome (CS) is a complex disorder caused by gain-of-function (GoF) mutations in ABCC9 and KCNJ8, which encode the SUR2 and Kir6.1 subunits, respectively, of vascular smooth muscle (VSM) KATP channels. CS includes dilated vasculature, marked cardiac hypertrophy, and other cardiovascular abnormalities. There is currently no targeted therapy, and it is unknown whether cardiovascular features can be reversed once manifest. Using combined transgenic and pharmacological approaches in a knockin mouse model of CS, we have shown that reversal of vascular and cardiac phenotypes can be achieved by genetic downregulation of KATP channel activity specifically in VSM, and by chronic administration of the clinically used KATP channel inhibitor, glibenclamide. These findings demonstrate that VSM KATP channel GoF underlies CS cardiac enlargement and that CS-associated abnormalities are reversible, and provide evidence of in vivo efficacy of glibenclamide as a therapeutic agent in CS.
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Affiliation(s)
- Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases.,Department of Cell Biology.,Department of Physiology
| | - Yan Huang
- Center for the Investigation of Membrane Excitability Diseases.,Department of Cell Biology.,Department of Physiology
| | - Zihan Yan
- Center for the Investigation of Membrane Excitability Diseases.,Division of Endocrinology, Department of Medicine, and
| | - Theresa M Harter
- Center for the Investigation of Membrane Excitability Diseases.,Department of Cell Biology.,Department of Physiology
| | - Carmen M Halabi
- Center for the Investigation of Membrane Excitability Diseases.,Division of Nephrology, Department of Pediatrics, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Rod Chalk
- Structural Genomics Consortium, University of Oxford, Oxford, United Kingdom
| | - Attila Kovacs
- Department of Medicine, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Gijs van Haaften
- Center for Molecular Medicine, Department of Genetics, University Medical Center Utrecht, Utrecht, Netherlands
| | - Maria S Remedi
- Center for the Investigation of Membrane Excitability Diseases.,Division of Endocrinology, Department of Medicine, and
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases.,Department of Cell Biology.,Department of Physiology
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Yokoi T, Enomoto Y, Tsurusaki Y, Naruto T, Kurosawa K. Cantú syndrome with novel pathogenic variant in nucleotide-binding domain 1 of ABCC9. Pediatr Int 2020; 62:1206-1208. [PMID: 32926509 DOI: 10.1111/ped.14273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/17/2020] [Accepted: 04/24/2020] [Indexed: 11/28/2022]
Affiliation(s)
- Takayuki Yokoi
- Division of Medical Genetics, Kanagawa Children's Medical Center, Yokohama, Japan.,Clinical Research Institute, Kanagawa Children's Medical Center, Yokohama, Japan
| | - Yumi Enomoto
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Yoshinori Tsurusaki
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Takuya Naruto
- Pediatrics and Developmental Biology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan
| | - Kenji Kurosawa
- Division of Medical Genetics, Kanagawa Children's Medical Center, Yokohama, Japan
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33
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Chihara M, Asahina A, Itoh M. A novel mutation in the KCNJ8 gene encoding the Kir6.1 subunit of an ATP-sensitive potassium channel in a Japanese patient with Cantú syndrome. J Eur Acad Dermatol Venereol 2020; 34:e476-e478. [PMID: 32215968 DOI: 10.1111/jdv.16384] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 03/16/2020] [Indexed: 11/27/2022]
Affiliation(s)
- M Chihara
- Department of Dermatology, The Jikei University School of Medicine, Tokyo, Japan
| | - A Asahina
- Department of Dermatology, The Jikei University School of Medicine, Tokyo, Japan
| | - M Itoh
- Department of Dermatology, The Jikei University School of Medicine, Tokyo, Japan.,Dermatology Clinic Itoiin, Shizuoka, Japan
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34
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Kortüm F, Niceta M, Magliozzi M, Dumic Kubat K, Robertson SP, Moresco A, Dentici ML, Baban A, Leoni C, Onesimo R, Obregon MG, Digilio MC, Zampino G, Novelli A, Tartaglia M, Kutsche K. Cantú syndrome versus Zimmermann-Laband syndrome: Report of nine individuals with ABCC9 variants. Eur J Med Genet 2020; 63:103996. [PMID: 32622958 DOI: 10.1016/j.ejmg.2020.103996] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 06/23/2020] [Accepted: 06/28/2020] [Indexed: 11/17/2022]
Abstract
Cantú syndrome (CS) is a rare developmental disorder characterized by a coarse facial appearance, macrocephaly, hypertrichosis, skeletal and cardiovascular anomalies and caused by heterozygous gain-of-function variants in ABCC9 and KCNJ8, encoding subunits of heterooctameric ATP-sensitive potassium (KATP) channels. CS shows considerable clinical overlap with Zimmermann-Laband syndrome (ZLS), a rare condition with coarse facial features, hypertrichosis, gingival overgrowth, intellectual disability of variable degree, and hypoplasia or aplasia of terminal phalanges and/or nails. ZLS is caused by heterozygous gain-of-function variants in KCNH1 or KCNN3, and gain-of-function KCNK4 variants underlie the clinically similar FHEIG (facial dysmorphism, hypertrichosis, epilepsy, intellectual disability/developmental delay, and gingival overgrowth) syndrome; KCNH1, KCNN3 and KCNK4 encode potassium channels. Within our research project on ZLS, we performed targeted Sanger sequencing of ABCC9 in 15 individuals tested negative for a mutation in the ZLS-associated genes and found two individuals harboring a heterozygous pathogenic ABCC9 missense variant. Through a collaborative effort, we identified a total of nine individuals carrying a monoallelic ABCC9 variant: five sporadic patients and four members of two unrelated families. Among the six detected ABCC9 missense variants, four [p.(Pro252Leu), p.(Thr259Lys), p.(Ala1064Pro), and p.(Arg1197His)] were novel. Systematic assessment of the clinical features in the nine cases with an ABCC9 variant highlights the significant clinical overlap between ZLS and CS that includes early developmental delay, hypertrichosis, gingival overgrowth, joint laxity, and hypoplasia of terminal phalanges and nails. Gain of K+ channel activity possibly accounts for significant clinical similarities of CS, ZLS and FHEIG syndrome and defines a new subgroup of potassium channelopathies.
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Affiliation(s)
- Fanny Kortüm
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Monia Magliozzi
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | | | - Stephen P Robertson
- Department of Women's and Children's Health, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - Angelica Moresco
- Paediatric Hospital Dr. Juan P. Garrahan, Buenos Aires, Argentina
| | - Maria Lisa Dentici
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Anwar Baban
- The European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart - ERN GUARD-Heart, Pediatric Cardiology and Arrhythmia/Syncope Units, Bambino Gesù Children Hospital and Research Institute, Rome, Italy
| | - Chiara Leoni
- Center of Rare Diseases and Congenital Defects, Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | - Roberta Onesimo
- Center of Rare Diseases and Congenital Defects, Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | | | - Maria Cristina Digilio
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Giuseppe Zampino
- Center of Rare Diseases and Congenital Defects, Fondazione Policlinico Universitario A. Gemelli, IRCCS, Rome, Italy
| | - Antonio Novelli
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Marco Tartaglia
- Genetics and Rare Diseases Research Division, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Kerstin Kutsche
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
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35
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McClenaghan C, Huang Y, Matkovich SJ, Kovacs A, Weinheimer CJ, Perez R, Broekelmann TJ, Harter TM, Lee JM, Remedi MS, Nichols CG. The Mechanism of High-Output Cardiac Hypertrophy Arising From Potassium Channel Gain-of-Function in Cantú Syndrome. FUNCTION (OXFORD, ENGLAND) 2020; 1:zqaa004. [PMID: 32865539 PMCID: PMC7446247 DOI: 10.1093/function/zqaa004] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/08/2020] [Accepted: 06/10/2020] [Indexed: 01/06/2023]
Abstract
Dramatic cardiomegaly arising from gain-of-function (GoF) mutations in the ATP-sensitive potassium (KATP) channels genes, ABCC9 and KCNJ8, is a characteristic feature of Cantú syndrome (CS). How potassium channel over-activity results in cardiac hypertrophy, as well as the long-term consequences of cardiovascular remodeling in CS, is unknown. Using genome-edited mouse models of CS, we therefore sought to dissect the pathophysiological mechanisms linking KATP channel GoF to cardiac remodeling. We demonstrate that chronic reduction of systemic vascular resistance in CS is accompanied by elevated renin-angiotensin signaling, which drives cardiac enlargement and blood volume expansion. Cardiac enlargement in CS results in elevation of basal cardiac output, which is preserved in aging. However, the cardiac remodeling includes altered gene expression patterns that are associated with pathological hypertrophy and are accompanied by decreased exercise tolerance, suggestive of reduced cardiac reserve. Our results identify a high-output cardiac hypertrophy phenotype in CS which is etiologically and mechanistically distinct from other myocardial hypertrophies, and which exhibits key features of high-output heart failure (HOHF). We propose that CS is a genetically-defined HOHF disorder and that decreased vascular smooth muscle excitability is a novel mechanism for HOHF pathogenesis.
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Affiliation(s)
- Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA,Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yan Huang
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA,Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Scot J Matkovich
- Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Attila Kovacs
- Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Carla J Weinheimer
- Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ron Perez
- Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Thomas J Broekelmann
- Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Theresa M Harter
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA,Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jin-Moo Lee
- Neurology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Maria S Remedi
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA,Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA,Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO 63110, USA,Corresponding author. E-mail:
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36
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Davis MJ, Kim HJ, Zawieja SD, Castorena-Gonzalez JA, Gui P, Li M, Saunders BT, Zinselmeyer BH, Randolph GJ, Remedi MS, Nichols CG. Kir6.1-dependent K ATP channels in lymphatic smooth muscle and vessel dysfunction in mice with Kir6.1 gain-of-function. J Physiol 2020; 598:3107-3127. [PMID: 32372450 DOI: 10.1113/jp279612] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 05/01/2020] [Indexed: 02/06/2023] Open
Abstract
KEY POINTS Spontaneous contractions are essential for normal lymph transport and these contractions are exquisitely sensitive to the KATP channel activator pinacidil. KATP channel Kir6.1 and SUR2B subunits are expressed in mouse lymphatic smooth muscle (LSM) and form functional KATP channels as verified by electrophysiological techniques. Global deletion of Kir6.1 or SUR2 subunits results in severely impaired lymphatic contractile responses to pinacidil. Smooth muscle-specific expression of Kir6.1 gain-of-function mutant (GoF) subunits results in profound lymphatic contractile dysfunction and LSM hyperpolarization that is partially rescued by the KATP inhibitor glibenclamide. In contrast, lymphatic endothelial-specific expression of Kir6.1 GoF has essentially no effect on lymphatic contractile function. The high sensitivity of LSM to KATP channel GoF offers an explanation for the lymphoedema observed in patients with Cantú syndrome, a disorder caused by gain-of-function mutations in genes encoding Kir6.1 or SUR2, and suggests that glibenclamide may be an appropriate therapeutic agent. ABSTRACT This study aimed to understand the functional expression of KATP channel subunits in distinct lymphatic cell types, and assess the consequences of altered KATP channel activity on lymphatic pump function. KATP channel subunits Kir6.1 and SUR2B were expressed in mouse lymphatic muscle by PCR, but only Kir6.1 was expressed in lymphatic endothelium. Spontaneous contractions of popliteal lymphatics from wild-type (WT) (C57BL/6J) mice, assessed by pressure myography, were very sensitive to inhibition by the SUR2-specific KATP channel activator pinacidil, which hyperpolarized both mouse and human lymphatic smooth muscle (LSM). In vessels from mice with deletion of Kir6.1 (Kir6.1-/- ) or SUR2 (SUR2[STOP]) subunits, contractile parameters were not significantly different from those of WT vessels, suggesting that basal KATP channel activity in LSM is not an essential component of the lymphatic pacemaker, and does not exert a strong influence over contractile strength. However, these vessels were >100-fold less sensitive than WT vessels to pinacidil. Smooth muscle-specific expression of a Kir6.1 gain-of-function (GoF) subunit resulted in severely impaired lymphatic contractions and hyperpolarized LSM. Membrane potential and contractile activity was partially restored by the KATP channel inhibitor glibenclamide. In contrast, lymphatic endothelium-specific expression of Kir6.1 GoF subunits had negligible effects on lymphatic contraction frequency or amplitude. Our results demonstrate a high sensitivity of lymphatic contractility to KATP channel activators through activation of Kir6.1/SUR2-dependent channels in LSM. In addition, they offer an explanation for the lymphoedema observed in patients with Cantú syndrome, a disorder caused by gain-of-function mutations in genes encoding Kir6.1/SUR2.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Hae Jin Kim
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Scott D Zawieja
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Jorge A Castorena-Gonzalez
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Peichun Gui
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Min Li
- Department of Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, 65212, USA
| | - Brian T Saunders
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Bernd H Zinselmeyer
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Gwendalyn J Randolph
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Maria S Remedi
- Department of Medicine, Washington University School of Medicine, St Louis, MO, 63110, USA
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO, 63110, USA
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37
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"Electrifying dysmorphology": Potassium channelopathies causing dysmorphic syndromes. ADVANCES IN GENETICS 2020; 105:137-174. [PMID: 32560786 DOI: 10.1016/bs.adgen.2020.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Potassium channels are a heterogeneous group of membrane-bound proteins, whose functions support a diverse range of biological processes. Genetic disorders arising from mutations in potassium channels are classically recognized by symptoms arising from acute channel dysfunction, such as periodic paralysis, ataxia, seizures, or cardiac conduction abnormalities, often in a patient with otherwise normal examination findings. In this chapter, we review a distinct subgroup of rare potassium channelopathies whose presentations are instead suggestive of a developmental disorder, with features including intellectual disability, craniofacial dysmorphism or other physical anomalies. Known conditions within this subgroup are: Andersen-Tawil syndrome, Birk-Barel syndrome, Cantú syndrome, Keppen-Lubinsky syndrome, Temple-Baraitser syndrome, Zimmerman-Laband syndrome and a very similar disorder called Bauer-Tartaglia or FHEIG syndrome. Ion channelopathies are unlikely to be routinely considered in the differential diagnosis of children presenting with developmental concerns, and so detailed description and photographs of the clinical phenotype are provided to aid recognition. For several of these disorders, functional characterization of the genetic mutations responsible has led to identification of candidate therapies, including drugs already commonly used for other indications, which adds further impetus to their prompt recognition. Together, these cases illustrate the potential for mechanistic insights gained from genetic diagnosis to drive translational work toward targeted, disease-modifying therapies for rare disorders.
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38
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Grange DK, Roessler HI, McClenaghan C, Duran K, Shields K, Remedi MS, Knoers NVAM, Lee JM, Kirk EP, Scurr I, Smithson SF, Singh GK, van Haelst MM, Nichols CG, van Haaften G. Cantú syndrome: Findings from 74 patients in the International Cantú Syndrome Registry. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2020; 181:658-681. [PMID: 31828977 DOI: 10.1002/ajmg.c.31753] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 10/14/2019] [Accepted: 10/18/2019] [Indexed: 11/11/2022]
Abstract
Cantú syndrome (CS), first described in 1982, is caused by pathogenic variants in ABCC9 and KCNJ8, which encode the regulatory and pore forming subunits of ATP-sensitive potassium (KATP ) channels, respectively. Multiple case reports of affected individuals have described the various clinical features of CS, but systematic studies are lacking. To define the effects of genetic variants on CS phenotypes and clinical outcomes, we have developed a standardized REDCap-based registry for CS. We report phenotypic features and associated genotypes on 74 CS subjects, with confirmed ABCC9 variants in 72 of the individuals. Hypertrichosis and a characteristic facial appearance are present in all individuals. Polyhydramnios during fetal life, hyperflexibility, edema, patent ductus arteriosus (PDA), cardiomegaly, dilated aortic root, vascular tortuosity of cerebral arteries, and migraine headaches are common features, although even with this large group of subjects, there is incomplete penetrance of CS-associated features, without clear correlation to genotype.
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Affiliation(s)
- Dorothy K Grange
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri.,Center for the Investigation of Membrane Excitability Diseases (CIMED)
| | - Helen I Roessler
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases (CIMED).,Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri
| | - Karen Duran
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Kathleen Shields
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri
| | - Maria S Remedi
- Center for the Investigation of Membrane Excitability Diseases (CIMED).,Department of Medicine, Division of Endocrinology, Washington University School of Medicine, St. Louis, Missouri
| | - Nine V A M Knoers
- Department of Genetics, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.,Department of Genetics, University Medical Center Groningen, Groningen, the Netherlands
| | - Jin-Moo Lee
- Department of Neurology and Radiology, Washington University School of Medicine, St. Louis, Missouri
| | - Edwin P Kirk
- Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Randwick, New South Wales, Australia
| | - Ingrid Scurr
- Department of Clinical Genetics, University Hospitals, Bristol, UK
| | - Sarah F Smithson
- Department of Clinical Genetics, University Hospitals, Bristol, UK
| | - Gautam K Singh
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri.,Center for the Investigation of Membrane Excitability Diseases (CIMED)
| | - Mieke M van Haelst
- Department of Clinical Genetics, VU Medical Center, VU University Amsterdam, Amsterdam, The Netherlands.,Department of Clinical Genetics, Amsterdam Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases (CIMED).,Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, Missouri
| | - Gijs van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
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39
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Walsh KB. Screening Technologies for Inward Rectifier Potassium Channels: Discovery of New Blockers and Activators. SLAS DISCOVERY 2020; 25:420-433. [PMID: 32292089 DOI: 10.1177/2472555220905558] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
K+ channels play a critical role in maintaining the normal electrical activity of excitable cells by setting the cell resting membrane potential and by determining the shape and duration of the action potential. In nonexcitable cells, K+ channels establish electrochemical gradients necessary for maintaining salt and volume homeostasis of body fluids. Inward rectifier K+ (Kir) channels typically conduct larger inward currents than outward currents, resulting in an inwardly rectifying current versus voltage relationship. This property of inward rectification results from the voltage-dependent block of the channels by intracellular polyvalent cations and makes these channels uniquely designed for maintaining the resting potential near the K+ equilibrium potential (EK). The Kir family of channels consist of seven subfamilies of channels (Kir1.x through Kir7.x) that include the classic inward rectifier (Kir2.x) channel, the G-protein-gated inward rectifier K+ (GIRK) (Kir3.x), and the adenosine triphosphate (ATP)-sensitive (KATP) (Kir 6.x) channels as well as the renal Kir1.1 (ROMK), Kir4.1, and Kir7.1 channels. These channels not only function to regulate electrical/electrolyte transport activity, but also serve as effector molecules for G-protein-coupled receptors (GPCRs) and as molecular sensors for cell metabolism. Of significance, Kir channels represent promising pharmacological targets for treating a number of clinical conditions, including cardiac arrhythmias, anxiety, chronic pain, and hypertension. This review provides a brief background on the structure, function, and pharmacology of Kir channels and then focuses on describing and evaluating current high-throughput screening (HTS) technologies, such as membrane potential-sensitive fluorescent dye assays, ion flux measurements, and automated patch clamp systems used for Kir channel drug discovery.
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Affiliation(s)
- Kenneth B Walsh
- Department of Pharmacology, Physiology & Neuroscience, School of Medicine, University of South Carolina, Columbia, SC, USA
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Roessler HI, Shields K, Grange DK, Knoers NVAM, van Haaften G, Hammond P, van Haelst MM. Three-dimensional facial morphology in Cantú syndrome. Am J Med Genet A 2020; 182:1041-1052. [PMID: 32100467 PMCID: PMC7217184 DOI: 10.1002/ajmg.a.61517] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/13/2020] [Accepted: 01/28/2020] [Indexed: 12/21/2022]
Abstract
Cantú syndrome (CS) was first described in 1982, and is caused by pathogenic variants in ABCC9 and KCNJ8 encoding regulatory and pore forming subunits of ATP-sensitive potassium (KATP ) channels, respectively. It is characterized by congenital hypertrichosis, osteochondrodysplasia, extensive cardiovascular abnormalities and distinctive facial anomalies including a broad nasal bridge, long philtrum, epicanthal folds, and prominent lips. Many genetic syndromes, such as CS, involve facial anomalies that serve as a significant clue in the initial identification of the respective disorder before clinical or molecular diagnosis are undertaken. However, an overwhelming number of CS patients receive misdiagnoses based on an evaluation of coarse facial features. By analyzing three-dimensional images of CS faces, we quantified facial dysmorphology in a cohort of both male and female CS patients with confirmed ABCC9 variants. Morphometric analysis of different regions of the face revealed gender-specific significant differences in face shape. Moreover, we show that 3D facial photographs can distinguish between CS and other genetic disorders with specific facial dysmorphologies that have been mistaken for CS-associated anomalies in the past, hence assisting in an earlier clinical and molecular diagnosis. This optimizes genetic counseling and reduces stress for patients and parents by avoiding unnecessary misdiagnosis.
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Affiliation(s)
- Helen I Roessler
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Kathleen Shields
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Dorothy K Grange
- Division of Genetics and Genomic Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA.,Center for the Investigation of Membrane Excitability Diseases (CIMED), St. Louis, Missouri, USA
| | - Nine V A M Knoers
- Deptartment of Genetics, University Medical Center Groningen, Groningen, The Netherlands
| | - Gijs van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Peter Hammond
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Mieke M van Haelst
- Department of Clinical Genetics, Amsterdam Medical Center, University of Amsterdam, Amsterdam, The Netherlands.,Department of Clinical Genetics, VU Medical Center, VU University Amsterdam, Amsterdam, The Netherlands
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Parrott A, Lombardo R, Brown N, Tretter JT, Riley L, Weaver KN. Cantu syndrome: A longitudinal review of vascular findings in three individuals. Am J Med Genet A 2020; 182:1243-1248. [PMID: 32065455 DOI: 10.1002/ajmg.a.61521] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/14/2020] [Accepted: 01/23/2020] [Indexed: 11/10/2022]
Abstract
Cantu syndrome is a rare autosomal dominant disorder caused by missense variants in ABCC9 and KCNJ8. It is characterized by hypertrichosis, neonatal macrosomia, coarse facial features, and skeletal anomalies. Reported cardiovascular anomalies include cardiomegaly, structural defects, collateral vessels, and rare report of arteriovenous malformation (AVM). Arterial dilation is reported in a few individuals including one with surgical intervention for a thoracic aortic aneurysm. The natural history of this aortopathy including the rate of progression or risk for dissection is unknown and longitudinal patient data is unavailable. We present data from vascular imaging in three individuals with genetically confirmed Cantu syndrome over 3 to 14 years of follow-up. All patients had generally stable aortic dilation, which did not reach the surgical threshold, including one individual followed closely through pregnancy. In adulthood, one individual had a maximum ascending aortic measurement of 4.2 cm. Two pediatric patients had aortic root or ascending z-scores of approximately +3. A large asymptomatic pelvic AVM was identified in one individual on head-pelvis MRI. While the data reported in these individuals is reassuring regarding the risk for progressive disease, further data from additional individuals with Cantu syndrome is needed to best inform screening recommendations, improve understanding of dissection risk, and guide management.
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Affiliation(s)
- Ashley Parrott
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Rachel Lombardo
- Department of Medical Genetics, UT Southwestern Medical Center, Dallas, Texas
| | - Nicole Brown
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Justin T Tretter
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Laura Riley
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Kathryn Nicole Weaver
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.,Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
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Huang Y, Hu D, Huang C, Nichols CG. Genetic Discovery of ATP-Sensitive K + Channels in Cardiovascular Diseases. Circ Arrhythm Electrophysiol 2020; 12:e007322. [PMID: 31030551 DOI: 10.1161/circep.119.007322] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The ATP-sensitive K+ (KATP) channels are hetero-octameric protein complexes comprising 4 pore-forming (Kir6.x) subunits and 4 regulatory sulfonylurea receptor (SURx) subunits. They are prominent in myocytes, pancreatic β cells, and neurons and link cellular metabolism with membrane excitability. Using genetically modified animals and genomic analysis in patients, recent studies have implicated certain ATP-sensitive K+ channel subtypes in physiological and pathological processes in a variety of cardiovascular diseases. In this review, we focus on the causal relationship between ATP-sensitive K+ channel activity and pathophysiology in the cardiovascular system, particularly from the perspective of genetic changes in human and animal models.
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Affiliation(s)
- Yan Huang
- Department of Cardiology, Renmin Hospital of Wuhan University; Cardiovascular Research Institute, Wuhan University, PR China (Y.H., D.H., C.H.).,Hubei Key Laboratory of Cardiology, Wuhan, PR China (Y.H., D.H., C.H.)
| | - Dan Hu
- Department of Cardiology, Renmin Hospital of Wuhan University; Cardiovascular Research Institute, Wuhan University, PR China (Y.H., D.H., C.H.).,Hubei Key Laboratory of Cardiology, Wuhan, PR China (Y.H., D.H., C.H.)
| | - Congxin Huang
- Department of Cardiology, Renmin Hospital of Wuhan University; Cardiovascular Research Institute, Wuhan University, PR China (Y.H., D.H., C.H.).,Hubei Key Laboratory of Cardiology, Wuhan, PR China (Y.H., D.H., C.H.)
| | - Colin G Nichols
- Center for the Investigation of Membrane Excitability Diseases and Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO (C.G.N.)
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Ma A, Gurnasinghani S, Kirk EP, McClenaghan C, Singh GK, Grange DK, Pandit C, Zhu Y, Roscioli T, Elakis G, Buckley M, Mehta B, Roberts P, Mervis J, Biggin A, Nichols CG. Glibenclamide treatment in a Cantú syndrome patient with a pathogenic ABCC9 gain-of-function variant: Initial experience. Am J Med Genet A 2019; 179:1585-1590. [PMID: 31175705 PMCID: PMC6899598 DOI: 10.1002/ajmg.a.61200] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/18/2019] [Accepted: 04/19/2019] [Indexed: 12/21/2022]
Abstract
Cantú syndrome (CS), characterized by hypertrichosis, distinctive facial features, and complex cardiovascular abnormalities, is caused by pathogenic variants in ABCC9 and KCNJ8 genes. These genes encode gain-of-function mutations in the regulatory (SUR2) and pore-forming (Kir6.1) subunits of KATP channels, respectively, suggesting that channel-blocking sulfonylureas could be a viable therapy. Here we report a neonate with CS, carrying a heterozygous ABCC9 variant (c.3347G>A, p.Arg1116His), born prematurely at 32 weeks gestation. Initial echocardiogram revealed a large patent ductus arteriosus (PDA), and high pulmonary pressures with enlarged right ventricle. He initially received surfactant and continuous positive airway pressure ventilation and was invasively ventilated for 4 weeks, until PDA ligation. After surgery, he still had ongoing bilevel positive airway pressure (BiPAP) requirement, but was subsequently weaned to nocturnal BiPAP. He was treated for pulmonary hypertension with Sildenafil, but failed to make further clinical improvement. A therapeutic glibenclamide trial was commenced in week 11 (initial dose of 0.05 mg-1 kg-1 day-1 in two divided doses). After 1 week of treatment, he began to tolerate time off BiPAP when awake, and edema improved. Glibenclamide was well tolerated, and the dose was slowly increased to 0.15 mg-1 kg-1 day-1 over the next 12 weeks. Mild transient hypoglycemia was observed, but there was no cardiovascular dysfunction. Confirmation of therapeutic benefit will require studies of more CS patients but, based on this limited experience, consideration should be given to glibenclamide as CS therapy, although problems associated with prematurity, and complications of hypoglycemia, might limit outcome in critically ill neonates with CS.
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Affiliation(s)
- Alan Ma
- Department of Clinical GeneticsChildren's Hospital at Westmead, Sydney Children's Hospital NetworkSydneyNew South WalesAustralia
- Discipline of Genomic MedicineSydney Medical School, University of SydneySydneyNew South WalesAustralia
| | - Sunita Gurnasinghani
- Department of Clinical GeneticsChildren's Hospital at Westmead, Sydney Children's Hospital NetworkSydneyNew South WalesAustralia
| | - Edwin P. Kirk
- Centre for Clinical GeneticsSydney Children's Hospital, Sydney Children's Hospital NetworkSydneyNew South WalesAustralia
- NSW Health Pathology East Genomics LaboratorySydneyNew South WalesAustralia
- School of Women's and Children's Health, University of NSWSydneyNew South WalesAustralia
| | - Conor McClenaghan
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of MedicineSt. LouisMissouri
- Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMissouri
| | - Gautam K. Singh
- Department of PediatricsWashington University School of MedicineSt. LouisMissouri
| | - Dorothy K. Grange
- Department of PediatricsWashington University School of MedicineSt. LouisMissouri
| | - Chetan Pandit
- Department of Respiratory and Sleep MedicineThe Children's Hospital at WestmeadSydneyNew South WalesAustralia
| | - Yung Zhu
- NSW Health Pathology East Genomics LaboratorySydneyNew South WalesAustralia
| | - Tony Roscioli
- Centre for Clinical GeneticsSydney Children's Hospital, Sydney Children's Hospital NetworkSydneyNew South WalesAustralia
- NSW Health Pathology East Genomics LaboratorySydneyNew South WalesAustralia
| | - George Elakis
- NSW Health Pathology East Genomics LaboratorySydneyNew South WalesAustralia
| | - Michael Buckley
- NSW Health Pathology East Genomics LaboratorySydneyNew South WalesAustralia
| | - Bhavesh Mehta
- Grace Centre for Newborn Intensive CareThe Children's Hospital at WestmeadSydneyNew South WalesAustralia
| | - Philip Roberts
- Department of CardiologyThe Children's Hospital at WestmeadSydneyNew South WalesAustralia
| | - Jonathan Mervis
- Department of CardiologyThe Children's Hospital at WestmeadSydneyNew South WalesAustralia
| | - Andrew Biggin
- Children's Hospital Westmead Clinical School, University of SydneyNew South WalesAustralia
- Institute of Endocrinology and Diabetes, The Children's Hospital at WestmeadSydneyNew South WalesAustralia
| | - Colin G. Nichols
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of MedicineSt. LouisMissouri
- Department of Cell Biology and PhysiologyWashington University School of MedicineSt. LouisMissouri
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Gao Q, Yang K, Chen D, Song Y, Qiao W, Sun X, Meng L, Bian Z. Antifibrotic Potential of MiR-335-3p in Hereditary Gingival Fibromatosis. J Dent Res 2019; 98:1140-1149. [DOI: 10.1177/0022034519863300] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Hereditary gingival fibromatosis (HGF) is a highly genetically heterogeneous disease, and current therapeutic method is limited to surgical resection with a high recurrence rate. MicroRNAs (miRNAs) are able to fine-tune large-scale target genes. Here we established a simple but effective computational strategy based on available miRNA target prediction algorithms to pinpoint the most potent miRNA that could negatively regulate a group of functional genes. Based on this rationale, miR-335-3p was top ranked by putatively targeting 85 verified profibrotic genes and 79 upregulated genes in HGF patients. Experimentally, downregulation of miR-355-3p was demonstrated in HGF-derived gingival fibroblasts as well as in transforming growth factor β–stimulated normal human gingival fibroblasts (NHGFs) compared to normal control. Ectopic miR-335-3p attenuated, whereas knockdown of miR-335-3p promoted, the fibrogenic activity of human gingival fibroblasts. Mechanically, miR-335-3p directly targeted SOS1, SMAD2/3, and CTNNB1 by canonical and noncanonical base paring. In particular, different portfolios of fibrotic markers were suppressed by silencing SOS1, SMAD2/3, or CTNNB1, respectively. Thus, our study first proposes a novel miRNA screening approach targeting a functionally related gene set and identifies miR-335-3p as a novel target for HGF treatment. Mechanically, miR-335-3p suppresses the fibrogenic activity of human gingival fibroblasts by repressing multiple core molecules in profibrotic networks. Our strategy provides a new paradigm in the treatment for HGF as well as other diseases.
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Affiliation(s)
- Q. Gao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - K. Yang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - D. Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Y. Song
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - W. Qiao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - X. Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - L. Meng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
| | - Z. Bian
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST) and Key Laboratory of Oral Biomedicine Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, Hubei, China
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McClenaghan C, Woo KV, Nichols CG. Pulmonary Hypertension and ATP-Sensitive Potassium Channels. Hypertension 2019; 74:14-22. [PMID: 31132951 DOI: 10.1161/hypertensionaha.119.12992] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Conor McClenaghan
- From the Department of Cell Biology and Physiology, and Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St Louis, MO (C.M., C.G.N.)
| | - Kel Vin Woo
- Department of Pediatrics, Division of Cardiology, Washington University School of Medicine, St Louis, MO (K.V.W.)
| | - Colin G Nichols
- From the Department of Cell Biology and Physiology, and Center for the Investigation of Membrane Excitability Diseases (CIMED), Washington University, St Louis, MO (C.M., C.G.N.)
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Chen X, Garon A, Wieder M, Houtman MJC, Zangerl-Plessl EM, Langer T, van der Heyden MAG, Stary-Weinzinger A. Computational Identification of Novel Kir6 Channel Inhibitors. Front Pharmacol 2019; 10:549. [PMID: 31178728 PMCID: PMC6543810 DOI: 10.3389/fphar.2019.00549] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 05/01/2019] [Indexed: 12/25/2022] Open
Abstract
KATP channels consist of four Kir6.x pore-forming subunits and four regulatory sulfonylurea receptor (SUR) subunits. These channels couple the metabolic state of the cell to membrane excitability and play a key role in physiological processes such as insulin secretion in the pancreas, protection of cardiac muscle during ischemia and hypoxic vasodilation of arterial smooth muscle cells. Abnormal channel function resulting from inherited gain or loss-of-function mutations in either the Kir6.x and/or SUR subunits are associated with severe diseases such as neonatal diabetes, congenital hyperinsulinism, or Cantú syndrome (CS). CS is an ultra-rare genetic autosomal dominant disorder, caused by dominant gain-of-function mutations in SUR2A or Kir6.1 subunits. No specific pharmacotherapeutic treatment options are currently available for CS. Kir6 specific inhibitors could be beneficial for the development of novel drug therapies for CS, particular for mutations, which lack high affinity for sulfonylurea inhibitor glibenclamide. By applying a combination of computational methods including atomistic MD simulations, free energy calculations and pharmacophore modeling, we identified several novel Kir6.1 inhibitors, which might be possible candidates for drug repurposing. The in silico predictions were confirmed using inside/out patch-clamp analysis. Importantly, Cantú mutation C166S in Kir6.2 (equivalent to C176S in Kir6.1) and S1020P in SUR2A, retained high affinity toward the novel inhibitors. Summarizing, the inhibitors identified in this study might provide a starting point toward developing novel therapies for Cantú disease.
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Affiliation(s)
- Xingyu Chen
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Arthur Garon
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Marcus Wieder
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Marien J. C. Houtman
- Department of Medical Physiology, Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, Netherlands
| | | | - Thierry Langer
- Department of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Marcel A. G. van der Heyden
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
- Department of Medical Physiology, Division of Heart and Lungs, University Medical Center Utrecht, Utrecht, Netherlands
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Houtman MJC, Chen X, Qile M, Duran K, van Haaften G, Stary-Weinzinger A, van der Heyden MAG. Glibenclamide and HMR1098 normalize Cantú syndrome-associated gain-of-function currents. J Cell Mol Med 2019; 23:4962-4969. [PMID: 31119887 PMCID: PMC7346732 DOI: 10.1111/jcmm.14329] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 03/13/2019] [Accepted: 03/25/2019] [Indexed: 12/15/2022] Open
Abstract
Cantú syndrome (CS) is caused by dominant gain-of-function mutation in ATP-dependent potassium channels. Cellular ATP concentrations regulate potassium current thereby coupling energy status with membrane excitability. No specific pharmacotherapeutic options are available to treat CS but IKATP channels are pharmaceutical targets in type II diabetes or cardiac arrhythmia treatment. We have been suggested that IKATP inhibitors, glibenclamide and HMR1098, normalize CS channels. IKATP in response to Mg-ATP, glibenclamide and HMR1098 were measured by inside-out patch-clamp electrophysiology. Results were interpreted in view of cryo-EM IKATP channel structures. Mg-ATP IC50 values of outward current were increased for D207E (0.71 ± 0.14 mmol/L), S1020P (1.83 ± 0.10), S1054Y (0.95 ± 0.06) and R1154Q (0.75 ± 0.13) channels compared to H60Y (0.14 ± 0.01) and wild-type (0.15 ± 0.01). HMR1098 dose-dependently inhibited S1020P and S1054Y channels in the presence of 0.15 mmol/L Mg-ATP, reaching, at 30 μmol/L, current levels displayed by wild-type and H60Y channels in the presence of 0.15 mmol/L Mg-ATP. Glibenclamide (10 μmol/L) induced similar normalization. S1054Y sensitivity to glibenclamide increases strongly at 0.5 mmol/L Mg-ATP compared to 0.15 mmol/L, in contrast to D207E and S1020P channels. Experimental findings agree with structural considerations. We conclude that CS channel activity can be normalized by existing drugs; however, complete normalization can be achieved at supraclinical concentrations only.
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Affiliation(s)
- Marien J C Houtman
- Division of Heart and Lungs, Department of Medical Physiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Xingyu Chen
- Department of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| | - Muge Qile
- Division of Heart and Lungs, Department of Medical Physiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Karen Duran
- Center for Molecular Medicine, Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Gijs van Haaften
- Center for Molecular Medicine, Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Marcel A G van der Heyden
- Division of Heart and Lungs, Department of Medical Physiology, University Medical Center Utrecht, Utrecht, The Netherlands
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Aortic and pulmonary artery dilatation in Cantu syndrome: expanding the phenotype. Clin Dysmorphol 2019; 28:167-169. [PMID: 30921097 DOI: 10.1097/mcd.0000000000000264] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Levin M, Pietak AM, Bischof J. Planarian regeneration as a model of anatomical homeostasis: Recent progress in biophysical and computational approaches. Semin Cell Dev Biol 2019; 87:125-144. [PMID: 29635019 PMCID: PMC6234102 DOI: 10.1016/j.semcdb.2018.04.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 04/03/2018] [Accepted: 04/06/2018] [Indexed: 12/22/2022]
Abstract
Planarian behavior, physiology, and pattern control offer profound lessons for regenerative medicine, evolutionary biology, morphogenetic engineering, robotics, and unconventional computation. Despite recent advances in the molecular genetics of stem cell differentiation, this model organism's remarkable anatomical homeostasis provokes us with truly fundamental puzzles about the origin of large-scale shape and its relationship to the genome. In this review article, we first highlight several deep mysteries about planarian regeneration in the context of the current paradigm in this field. We then review recent progress in understanding of the physiological control of an endogenous, bioelectric pattern memory that guides regeneration, and how modulating this memory can permanently alter the flatworm's target morphology. Finally, we focus on computational approaches that complement reductive pathway analysis with synthetic, systems-level understanding of morphological decision-making. We analyze existing models of planarian pattern control and highlight recent successes and remaining knowledge gaps in this interdisciplinary frontier field.
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Affiliation(s)
- Michael Levin
- Allen Discovery Center at Tufts University, Medford, MA 02155, United States; Biology Department, Tufts University, Medford, MA 02155, United States.
| | - Alexis M Pietak
- Allen Discovery Center at Tufts University, Medford, MA 02155, United States
| | - Johanna Bischof
- Allen Discovery Center at Tufts University, Medford, MA 02155, United States; Biology Department, Tufts University, Medford, MA 02155, United States
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50
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Wu P, Wang K, Zhou J, Yang Q, Yang X, Jiang A, Jiang Y, Li M, Zhu L, Bai L, Li X, Tang G. A genome wide association study for the number of animals born dead in domestic pigs. BMC Genet 2019; 20:4. [PMID: 30616509 PMCID: PMC6324166 DOI: 10.1186/s12863-018-0692-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 10/31/2018] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND The number of animals born dead, which includes the number of mummified (NM) and stillborn (NS) animals, is the most important trait to directly quantify the reproductive loss in domestic pigs. In this study, 282 Landrace sows and 250 Large White sows were genotyped by sequencing (GBS). A total of 816 and 1068 litter records for NM and NS were collected from them. A genome-wide association study (GWAS) was conducted to reveal the genetic difference between NM and NS. RESULTS A total of 248 and 10 genome-wide significant SNPs were detected for NM and NS across numerous parities in Landrace pigs. The corresponding numbers for Large White pigs were 175 and 6, respectively. All of the detected SNPs were parity specific for both NM and NS in two breeds. Based on significant SNPs, in total 242 (146 for Landrace pig, 96 for Large White pig) and 10 significant chromosome regions (8 for Landrace pigs, 2 for Large White pigs) were found for NM and NS, respectively. Among them, 237 (142 for Landrace pig, 95 for Large White pig) and 8 significant chromosome regions (6 for Landrace pigs, 2 for Large White pigs) for NM and NS were not reported in previous studies. A list of candidate genes at the identified loci was proposed, including HMGB1, SOX5, KCNJ8, ABCC9 and YY1 for NM, ASTN1 for NS. CONCLUSION This is the first time when GBS data was used to identify genetic regions affecting NM and NS in Landrace and Large White pigs. Many identified informative SNPs and candidate genes advance our understanding of the genetic architecture of NM and NS in pigs. However, further studies are needed to validate using larger populations with more breeds.
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Affiliation(s)
- Pingxian Wu
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Kai Wang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Jie Zhou
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Qiang Yang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Xidi Yang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Anan Jiang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Yanzhi Jiang
- College of Life Science, Sichuan Agricultural University, Yaan, Sichuan China
| | - Mingzhou Li
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Li Zhu
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Lin Bai
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Xuewei Li
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
| | - Guoqing Tang
- College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, Sichuan China
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