1
|
Donowitz M, Tse CM, Sarker R, Lin R, Dokladny K, Rawat M, Horwitz I, Ye C, McNamara G, In J, Kell A, Guo C, JuiTsai S, Vong T, Karaba A, Singh V, Sachithanandham J, Pekosz A, Cox A, Bradfute S, Zachos NC, Gould S, Kovbasnjuk O. COVID-19 Diarrhea is Inflammatory, Caused by Direct Viral Effects Plus Major Role of Virus-induced Cytokines. Cell Mol Gastroenterol Hepatol 2024; 18:101383. [PMID: 39089626 DOI: 10.1016/j.jcmgh.2024.101383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2024] [Revised: 07/08/2024] [Accepted: 07/23/2024] [Indexed: 08/04/2024]
Abstract
BACKGROUND & AIMS Diarrhea occurs in up to 50% of cases of COVID-19. Nonetheless, the pathophysiologic mechanism(s) have not been determined. METHODS This was examined using normal human enteroid monolayers exposed apically to live SARS-CoV-2 or non-replicating virus-like particles (VLPs) bearing the 4 SARS-CoV-2 structural proteins or irradiated virus, all of which bound and entered enterocytes. RESULTS Live virus and VLPs incrieased secretion of multiple cytokines and reduced mRNAs of ACE2, NHE3, and DRA. Interleukin (IL)-6 plus IL-8 alone reduced NHE3 mRNA and protein and DRA mRNA and protein. Neither VLPs nor IL-6 plus IL-8 alone altered Cl- secretion, but together they caused Cl- secretion, which was Ca2+-dependent, CFTR-independent, blocked partially by a specific TMEM16A inhibitor, and entirely by a general TMEM16 family inhibitor. VLPs and irradiated virus, but not IL-6 plus IL-8, produced Ca2+ waves that began within minutes of VLP exposure, lasted for at least 60 minutes, and were prevented by pretreatment with apyrase, a P2Y1 receptor antagonist, and general TMEM16 family inhibitor but not by the specific TMEM16A inhibitor. CONCLUSIONS The pathophysiology of COVID-19 diarrhea appears to be a unique example of a calcium-dependent inflammatory diarrhea that is caused by direct viral effects plus the virus-induced intestinal epithelial cytokine secretion.
Collapse
Affiliation(s)
- Mark Donowitz
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Physiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
| | - Chung-Ming Tse
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Rafiq Sarker
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ruxian Lin
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Karol Dokladny
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Manmeet Rawat
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Ivy Horwitz
- University of New Mexico Center for Global Health, Albuquerque, New Mexico
| | - ChunYan Ye
- University of New Mexico Center for Global Health, Albuquerque, New Mexico
| | - George McNamara
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Julie In
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Alison Kell
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| | - Chenxu Guo
- Department of Biological Chemistry, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Shang JuiTsai
- Department of Biological Chemistry, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Tyrus Vong
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Andrew Karaba
- Division of Infectious Diseases, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Varsha Singh
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jaiprasath Sachithanandham
- Department of Microbiology and Immunology, Bloomberg School of Public Health of the Johns Hopkins University, Baltimore, Maryland
| | - Andy Pekosz
- Department of Microbiology and Immunology, Bloomberg School of Public Health of the Johns Hopkins University, Baltimore, Maryland
| | - Andrea Cox
- Division of Infectious Diseases, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Steven Bradfute
- Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico; University of New Mexico Center for Global Health, Albuquerque, New Mexico
| | - Nicholas C Zachos
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Steven Gould
- Department of Biological Chemistry, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Olga Kovbasnjuk
- Division of Gastroenterology and Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico
| |
Collapse
|
2
|
Genovese M, Galietta LJV. Anoctamin pharmacology. Cell Calcium 2024; 121:102905. [PMID: 38788257 DOI: 10.1016/j.ceca.2024.102905] [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: 03/21/2024] [Revised: 05/07/2024] [Accepted: 05/09/2024] [Indexed: 05/26/2024]
Abstract
TMEM16 proteins, also known as anoctamins, are a family of ten membrane proteins with various tissue expression and subcellular localization. TMEM16A (anoctamin 1) is a plasma membrane protein that acts as a calcium-activated chloride channel. It is expressed in many types of epithelial cells, smooth muscle cells and some neurons. In airway epithelial cells, TMEM16A expression is particularly enhanced by inflammatory stimuli that also promote goblet cell metaplasia and mucus hypersecretion. Therefore, pharmacological modulation of TMEM16A could be beneficial to improve mucociliary clearance in chronic obstructive respiratory diseases. However, the correct approach to modulate TMEM16A activity (activation or inhibition) is still debated. Pharmacological inhibitors of TMEM16A could also be useful as anti-hypertensive agents given the TMEM16A role in smooth muscle contraction. In contrast to TMEM16A, TMEM16F (anoctamin 6) behaves as a calcium-activated phospholipid scramblase, responsible for the externalization of phosphatidylserine on cell surface. Inhibitors of TMEM16F could be useful as anti-coagulants and anti-viral agents. The role of other anoctamins as therapeutic targets is still unclear since their physiological role is still to be defined.
Collapse
Affiliation(s)
- Michele Genovese
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli (NA), Italy
| | - Luis J V Galietta
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli (NA), Italy; Department of Translational Medical Sciences (DISMET), University of Naples "Federico II", Italy.
| |
Collapse
|
3
|
Schreiber R, Ousingsawat J, Kunzelmann K. The anoctamins: Structure and function. Cell Calcium 2024; 120:102885. [PMID: 38642428 DOI: 10.1016/j.ceca.2024.102885] [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: 02/21/2024] [Revised: 04/03/2024] [Accepted: 04/04/2024] [Indexed: 04/22/2024]
Abstract
When activated by increase in intracellular Ca2+, anoctamins (TMEM16 proteins) operate as phospholipid scramblases and as ion channels. Anoctamin 1 (ANO1) is the Ca2+-activated epithelial anion-selective channel that is coexpressed together with the abundant scramblase ANO6 and additional intracellular anoctamins. In salivary and pancreatic glands, ANO1 is tightly packed in the apical membrane and secretes Cl-. Epithelia of airways and gut use cystic fibrosis transmembrane conductance regulator (CFTR) as an apical Cl- exit pathway while ANO1 supports Cl- secretion mainly by facilitating activation of luminal CFTR and basolateral K+ channels. Under healthy conditions ANO1 modulates intracellular Ca2+ signals by tethering the endoplasmic reticulum, and except of glands its direct secretory contribution as Cl- channel might be small, compared to CFTR. In the kidneys ANO1 supports proximal tubular acid secretion and protein reabsorption and probably helps to excrete HCO3-in the collecting duct epithelium. However, under pathological conditions as in polycystic kidney disease, ANO1 is strongly upregulated and may cause enhanced proliferation and cyst growth. Under pathological condition, ANO1 and ANO6 are upregulated and operate as secretory channel/phospholipid scramblases, partly by supporting Ca2+-dependent processes. Much less is known about the role of other epithelial anoctamins whose potential functions are discussed in this review.
Collapse
Affiliation(s)
- Rainer Schreiber
- Physiological Institute, University of Regensburg, University street 31, D-93053 Regensburg, Germany
| | - Jiraporn Ousingsawat
- Physiological Institute, University of Regensburg, University street 31, D-93053 Regensburg, Germany
| | - Karl Kunzelmann
- Physiological Institute, University of Regensburg, University street 31, D-93053 Regensburg, Germany.
| |
Collapse
|
4
|
Son GY, Zou A, Wahl A, Huang KT, Vinu M, Zorgit S, Zhou F, Wagner L, Idaghdour Y, Yule DI, Feske S, Lacruz RS. Loss of STIM1 and STIM2 in salivary glands disrupts ANO1 function but does not induce Sjogren's disease. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.08.574702. [PMID: 38260625 PMCID: PMC10802497 DOI: 10.1101/2024.01.08.574702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Sjogren's disease (SjD) is an autoimmune disease characterized by xerostomia (dry mouth), lymphocytic infiltration into salivary glands and the presence of SSA and SSB autoantibodies. Xerostomia is caused by hypofunction of the salivary glands and has been involved in the development of SjD. Saliva production is regulated by parasympathetic input into the glands initiating intracellular Ca 2+ signals that activate the store operated Ca 2+ entry (SOCE) pathway eliciting sustained Ca 2+ influx. SOCE is mediated by the STIM1 and STIM2 proteins and the ORAI1 Ca 2+ channel. However, there are no studies on the effects of lack of STIM1/2 function in salivary acini in animal models and its impact on SjD. Here we report that male and female mice lacking Stim1 and Stim2 ( Stim1/2 K14Cre ) in salivary glands showed reduced intracellular Ca 2+ levels via SOCE in parotid acini and hyposalivate upon pilocarpine stimulation. Bulk RNASeq of the parotid glands of Stim1/2 K14Cre mice showed a decrease in the expression of Stim1/2 but no other Ca 2+ associated genes mediating saliva fluid secretion. SOCE was however functionally required for the activation of the Ca 2+ activated chloride channel ANO1. Despite hyposalivation, ageing Stim1/2 K14Cre mice showed no evidence of lymphocytic infiltration in the glands or elevated levels of SSA or SSB autoantibodies in the serum, which may be linked to the downregulation of the toll-like receptor 8 ( Tlr8 ). By contrast, salivary gland biopsies of SjD patients showed increased STIM1 and TLR8 expression, and induction of SOCE in a salivary gland cell line increased the expression of TLR8 . Our data demonstrate that SOCE is an important activator of ANO1 function and saliva fluid secretion in salivary glands. They also provide a novel link between SOCE and TLR8 signaling which may explain why loss of SOCE does not result in SjD.
Collapse
|
5
|
Sanders KM, Drumm BT, Cobine CA, Baker SA. Ca 2+ dynamics in interstitial cells: foundational mechanisms for the motor patterns in the gastrointestinal tract. Physiol Rev 2024; 104:329-398. [PMID: 37561138 PMCID: PMC11281822 DOI: 10.1152/physrev.00036.2022] [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: 11/16/2022] [Revised: 06/29/2023] [Accepted: 08/06/2023] [Indexed: 08/11/2023] Open
Abstract
The gastrointestinal (GI) tract displays multiple motor patterns that move nutrients and wastes through the body. Smooth muscle cells (SMCs) provide the forces necessary for GI motility, but interstitial cells, electrically coupled to SMCs, tune SMC excitability, transduce inputs from enteric motor neurons, and generate pacemaker activity that underlies major motor patterns, such as peristalsis and segmentation. The interstitial cells regulating SMCs are interstitial cells of Cajal (ICC) and PDGF receptor (PDGFR)α+ cells. Together these cells form the SIP syncytium. ICC and PDGFRα+ cells express signature Ca2+-dependent conductances: ICC express Ca2+-activated Cl- channels, encoded by Ano1, that generate inward current, and PDGFRα+ cells express Ca2+-activated K+ channels, encoded by Kcnn3, that generate outward current. The open probabilities of interstitial cell conductances are controlled by Ca2+ release from the endoplasmic reticulum. The resulting Ca2+ transients occur spontaneously in a stochastic manner. Ca2+ transients in ICC induce spontaneous transient inward currents and spontaneous transient depolarizations (STDs). Neurotransmission increases or decreases Ca2+ transients, and the resulting depolarizing or hyperpolarizing responses conduct to other cells in the SIP syncytium. In pacemaker ICC, STDs activate voltage-dependent Ca2+ influx, which initiates a cluster of Ca2+ transients and sustains activation of ANO1 channels and depolarization during slow waves. Regulation of GI motility has traditionally been described as neurogenic and myogenic. Recent advances in understanding Ca2+ handling mechanisms in interstitial cells and how these mechanisms influence motor patterns of the GI tract suggest that the term "myogenic" should be replaced by the term "SIPgenic," as this review discusses.
Collapse
Affiliation(s)
- Kenton M Sanders
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada-Reno, Reno, Nevada, United States
| | - Bernard T Drumm
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Caroline A Cobine
- Smooth Muscle Research Centre, Dundalk Institute of Technology, Dundalk, Ireland
| | - Salah A Baker
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada-Reno, Reno, Nevada, United States
| |
Collapse
|
6
|
Qu C, Guan X, Li C, Zhu X, Ma T, Li H, Yu B, Yang H. Sesquiterpene lactones improve secretory diarrhea symptoms by inhibiting intestinal Ca 2+-activated Cl - channel activities directly and indirectly. Eur J Pharmacol 2023; 955:175917. [PMID: 37473982 DOI: 10.1016/j.ejphar.2023.175917] [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: 03/29/2023] [Revised: 07/15/2023] [Accepted: 07/17/2023] [Indexed: 07/22/2023]
Abstract
Secretory diarrhea caused by bacteria and viruses is usually accompanied by activation of the cystic fibrosis transmembrane conductance regulator (CFTR) and calcium-activated Cl- channels (CaCCs) in the intestinal epithelium. Inhibition of CFTR and CaCCs activities significantly reduces fluid losses and intestinal motility in diarrheal diseases. For this reason, CFTR and CaCCs are potential targets of therapeutic drug screening. Here, we reported that the sesquiterpene lactones, alantolactone (AL) and isoalantolactone (iAL), significantly inhibited ATP and Eact-induced short-circuit currents in T84, HT-29 and Fischer rat thyroid (FRT) cells expressing transmembrane protein 16A (TMEM16A) in a concentration-dependent manner. AL and iAL also inhibited the CaCC-mediated short-circuit currents induced by carbachol in the mouse colons. Both compounds inhibited forskolin-induced currents in T84 cells but did not significantly affect mouse colons. In vivo studies indicated that AL and iAL attenuated gastrointestinal motility and decreased watery diarrhea in rotavirus-infected neonatal mice. Preliminary mechanism studies showed that AL and iAL inhibited CaCCs at least partially by inhibiting Ca2+ release and basolateral membrane K+ channels activity. These findings suggest a new pharmacological activity of sesquiterpene lactone compounds that might lead to the development of treatments for rotaviral secretory diarrhea.
Collapse
Affiliation(s)
- Chao Qu
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China
| | - Xin Guan
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China; Stem Cell Clinical Research Center, National Joint Engineering Laboratory, The First Affiliated Hospital of Dalian Medical University, Dalian, China; Dalian Innovation Institute of Stem Cell and Precision Medicine, Dalian, China
| | - Chang Li
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China
| | - Xiaojuan Zhu
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China
| | - Tonghui Ma
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China
| | - Hongyan Li
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China.
| | - Bo Yu
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China.
| | - Hong Yang
- Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, School of Life Science, Liaoning Normal University, Dalian, China.
| |
Collapse
|
7
|
Ning N, Luo D, Xia W, Mou G, Zhao J, Zhang J, Li C, Wang H, Li J. Dysregulation of TMEM16A impairs oviductal transport of embryos. Am J Physiol Cell Physiol 2023; 325:C623-C632. [PMID: 37458439 DOI: 10.1152/ajpcell.00031.2023] [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: 01/27/2023] [Revised: 07/10/2023] [Accepted: 07/10/2023] [Indexed: 08/25/2023]
Abstract
Ectopic pregnancy is an acute abdominalgia in obstetrics and gynecology, especially in fallopian tubal pregnancy. The ion channel protein transmembrane protein 16A (TMEM16A) is widely distributed in various tissues, even in the oviduct. In this study, we showed that TMEM16A was expressed in the human fallopian tube and was upregulated in patients with tubal pregnancy. By measuring isolated fallopian tube tissues, we found that TMEM16A was involved in regulating not only the contraction of muscle strips but also the beat frequency of cilia. In addition, pharmacological activation or inhibition of TMEM16A could lead to retention of embryos in oviducts. Moreover, the embryos in oviducts were delayed in development and some of them had malformations and deletions. The total number of embryos in the oviducts and uterus was significantly less than that of the control group. Furthermore, we detected changes in the level of m6A methylation, where the relevant writers and readers were reduced in tubal tissues from tubal pregnancies. In m6A mRNA methylation, writers catalyze the addition of methyl groups to cytosine residues and readers bind to the methyl groups and affect gene translation. In human fallopian tube epithelial cell line FTE187, we found that interference with methyltransferase 3 (METTL3) expression increased TMEM16A, suggesting that TMEM16A might be regulated by m6A methylation. In general, our study revealed a novel regulatory point for embryo transport and development, introducing a new role for the diagnosis and treatment of tubal pregnancy.NEW & NOTEWORTHY The ion channel protein TMEM16A is expressed in the epithelium and smooth muscle of the human fallopian tube and is upregulated in patients with tubal pregnancy. TMEM16A is involved in regulating the smooth muscle contraction and the cilia beating. Dysregulated TMEM16A may result in embryo retention in the oviduct and delayed early embryo development. Our study reveals a new regulatory point for embryo transport and development.
Collapse
Affiliation(s)
- Nannan Ning
- Department of Clinical Laboratory, Qilu Hospital of Shandong University, Jinan, People's Republic of China
- Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application, Jinan, People's Republic of China
| | - Dan Luo
- Department of Breast Surgery, Qilu Hospital of Shandong University, Jinan, People's Republic of China
| | - Wei Xia
- Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, People's Republic of China
- Shanghai Key Laboratory Embryo Original Diseases, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China
| | - Guangjing Mou
- Department of Physiology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People's Republic of China
| | - Jiangli Zhao
- Department of Physiology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People's Republic of China
| | - Jian Zhang
- Department of Obstetrics and Gynecology, International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, People's Republic of China
| | - Cheng Li
- Obstetrics and Gynecology Hospital, Institute of Reproduction and Development, Fudan University, Shanghai, People's Republic of China
| | - Hongchun Wang
- Department of Clinical Laboratory, Qilu Hospital of Shandong University, Jinan, People's Republic of China
- Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application, Jinan, People's Republic of China
| | - Jingxin Li
- Department of Physiology, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People's Republic of China
| |
Collapse
|
8
|
Marando A, Di Blasi E, Tucci F, Aquilano MC, Bonoldi E. DOG1 expression in neuroendocrine neoplasms: Potential applications and diagnostic pitfalls. Pathol Res Pract 2023; 248:154623. [PMID: 37331184 DOI: 10.1016/j.prp.2023.154623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/20/2023]
Abstract
Neuroendocrine neoplasms represent a heterogeneous group of rare tumors, more frequently arising from gastroenteropancreatic tract and lungs. At the time of diagnosis, 20% of cases are metastatic, and 10% of cases are considered as cancer of unknown primary origin. Several immunohistochemical markers are routinely used to confirm the neuroendocrine differentiation, first among all Synaptophysin and Chromogranin-A; on the other hand, different immunohistochemical markers are used to establish primary anatomical site, as TTF1, CDX2, Islet-1 and Calcitonin, but no marker is available in order to distinguish among different sites of the digestive tract. DOG1 (discovered on GIST-1) is a gene normally expressed in interstitial cells of Cajal and, in routine practice, DOG1 immunostaining is used in diagnosis of GIST (gastrointestinal stromal tumor). DOG1 expression has been described in several neoplasms other than GIST, both in mesenchymal and epithelial neoplasms. In the present study, DOG1 immunostaining has been performed in a large cohort of neuroendocrine neoplasms, including neuroendocrine tumors and neuroendocrine carcinomas, in order to evaluate frequency, intensity and pattern of expression in different anatomical site and in different tumor grade. DOG1 expression was detected in a large percentage of neuroendocrine tumors, with statistically significant association between DOG1 expression and gastrointestinal tract neuroendocrine tumors. As a consequence, DOG1 could be included in marker panel for the identification of primary site in neuroendocrine metastases of unknown primary origin; moreover, these results recommend careful evaluation of DOG1 expression in gastrointestinal neoplasms, in particular in differential diagnosis between epithelioid GIST and neuroendocrine tumors.
Collapse
Affiliation(s)
- A Marando
- Department of Surgical Pathology, Niguarda Hospital, Milano, Italy.
| | - E Di Blasi
- School of Pathology, University of Milan, Milan, Italy
| | - F Tucci
- School of Pathology, University of Milan, Milan, Italy
| | - M C Aquilano
- Department of Surgical Pathology, Niguarda Hospital, Milano, Italy
| | - E Bonoldi
- Department of Surgical Pathology, Niguarda Hospital, Milano, Italy
| |
Collapse
|
9
|
Kulkarni S, Li Q, Singhi AD, Liu S, Monga SP, Feranchak AP. TMEM16A partners with mTOR to influence pathways of cell survival, proliferation, and migration in cholangiocarcinoma. Am J Physiol Gastrointest Liver Physiol 2023; 325:G122-G134. [PMID: 37219012 PMCID: PMC10390053 DOI: 10.1152/ajpgi.00270.2022] [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: 11/11/2022] [Revised: 05/04/2023] [Accepted: 05/17/2023] [Indexed: 05/24/2023]
Abstract
Expression of transmembrane protein 16 A (TMEM16A), a calcium activated chloride channel, is elevated in some human cancers and impacts tumor cell proliferation, metastasis, and patient outcome. Evidence presented here uncovers a molecular synergy between TMEM16A and mechanistic/mammalian target of rapamycin (mTOR), a serine-threonine kinase that is known to promote cell survival and proliferation in cholangiocarcinoma (CCA), a lethal cancer of the secretory cells of bile ducts. Analysis of gene and protein expression in human CCA tissue and CCA cell line detected elevated TMEM16A expression and Cl- channel activity. The Cl- channel activity of TMEM16A impacted the actin cytoskeleton and the ability of cells to survive, proliferate, and migrate as revealed by pharmacological inhibition studies. The basal activity of mTOR, too, was elevated in the CCA cell line compared with the normal cholangiocytes. Molecular inhibition studies provided further evidence that TMEM16A and mTOR were each able to influence the regulation of the other's activity or expression respectively. Consistent with this reciprocal regulation, combined TMEM16A and mTOR inhibition produced a greater loss of CCA cell survival and migration than their individual inhibition alone. Together these data reveal that the aberrant TMEM16A expression and cooperation with mTOR contribute to a certain advantage in CCA.NEW & NOTEWORTHY This study points to the dysregulation of transmembrane protein 16 A (TMEM16A) expression and activity in cholangiocarcinoma (CCA), the inhibition of which has functional consequences. Dysregulated TMEM16A exerts an influence on the regulation of mechanistic/mammalian target of rapamycin (mTOR) activity. Moreover, the reciprocal regulation of TMEM16A by mTOR demonstrates a novel connection between these two protein families. These findings support a model in which TMEM16A intersects the mTOR pathway to regulate cell cytoskeleton, survival, proliferation, and migration in CCA.
Collapse
Affiliation(s)
- Sucheta Kulkarni
- Division of Gastroenterology, Department of Pediatrics, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Qin Li
- Division of Gastroenterology, Department of Pediatrics, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Aatur D Singhi
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Pathology, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Silvia Liu
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Pathology, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Satdarshan P Monga
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Pathology, University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Andrew P Feranchak
- Division of Gastroenterology, Department of Pediatrics, Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| |
Collapse
|
10
|
Gonçalves AN, Moura RS, Correia-Pinto J, Nogueira-Silva C. Intraluminal chloride regulates lung branching morphogenesis: involvement of PIEZO1/PIEZO2. Respir Res 2023; 24:42. [PMID: 36740669 PMCID: PMC9901166 DOI: 10.1186/s12931-023-02328-2] [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: 04/30/2022] [Accepted: 01/13/2023] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Clinical and experimental evidence shows lung fluid volume as a modulator of fetal lung growth with important value in treating fetal lung hypoplasia. Thus, understanding the mechanisms underlying these morphological dynamics has been the topic of multiple investigations with, however, limited results, partially due to the difficulty of capturing or recapitulating these movements in the lab. In this sense, this study aims to establish an ex vivo model allowing the study of lung fluid function in branching morphogenesis and identify the subsequent molecular/ cellular mechanisms. METHODS Ex vivo lung explant culture was selected as a model to study branching morphogenesis, and intraluminal injections were performed to change the composition of lung fluid. Distinct chloride (Cl-) concentrations (5.8, 29, 143, and 715 mM) or Cl- channels inhibitors [antracene-9-carboxylic acid (A9C), cystic fibrosis transmembrane conductance regulator inhibitor172 (CFTRinh), and calcium-dependent Cl- channel inhibitorA01 (CaCCinh)] were injected into lung lumen at two timepoints, day0 (D0) and D2. At D4, morphological and molecular analyses were performed in terms of branching morphogenesis, spatial distribution (immunofluorescence), and protein quantification (western blot) of mechanoreceptors (PIEZO1 and PIEZO2), neuroendocrine (bombesin, ghrelin, and PGP9.5) and smooth muscle [alpha-smooth muscle actin (α-SMA) and myosin light chain 2 (MLC2)] markers. RESULTS For the first time, we described effective intraluminal injections at D0 and D2 and demonstrated intraluminal movements at D4 in ex vivo lung explant cultures. Through immunofluorescence assay in in vivo and ex vivo branching morphogenesis, we show that PGP9.5 colocalizes with PIEZO1 and PIEZO2 receptors. Fetal lung growth is increased at higher [Cl-], 715 mM Cl-, through the overexpression of PIEZO1, PIEZO2, ghrelin, bombesin, MLC2, and α-SMA. In contrast, intraluminal injection of CFTRinh or CaCCinh decreases fetal lung growth and the expression of PIEZO1, PIEZO2, ghrelin, bombesin, MLC2, and α-SMA. Finally, the inhibition of PIEZO1/PIEZO2 by GsMTx4 decreases branching morphogenesis and ghrelin, bombesin, MLC2, and α-SMA expression in an intraluminal injection-independent manner. CONCLUSIONS Our results identify PIEZO1/PIEZO2 expressed in neuroendocrine cells as a regulator of fetal lung growth induced by lung fluid.
Collapse
Affiliation(s)
- Ana N. Gonçalves
- grid.10328.380000 0001 2159 175XSchool of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus de Gualtar, Gualtar, 4710-057 Braga, Portugal ,grid.10328.380000 0001 2159 175XLife and Health Sciences Research Institute/3B’s-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Rute S. Moura
- grid.10328.380000 0001 2159 175XSchool of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus de Gualtar, Gualtar, 4710-057 Braga, Portugal ,grid.10328.380000 0001 2159 175XLife and Health Sciences Research Institute/3B’s-PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Jorge Correia-Pinto
- grid.10328.380000 0001 2159 175XSchool of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus de Gualtar, Gualtar, 4710-057 Braga, Portugal ,grid.10328.380000 0001 2159 175XLife and Health Sciences Research Institute/3B’s-PT Government Associate Laboratory, Braga/Guimarães, Portugal ,Department of Pediatric Surgery, Hospital de Braga, Braga, Portugal
| | - Cristina Nogueira-Silva
- School of Medicine, Life and Health Sciences Research Institute (ICVS), University of Minho, Campus de Gualtar, Gualtar, 4710-057, Braga, Portugal. .,Life and Health Sciences Research Institute/3B's-PT Government Associate Laboratory, Braga/Guimarães, Portugal. .,Department of Obstetrics and Gynecology, Hospital de Braga, Braga, Portugal.
| |
Collapse
|
11
|
Jimenez C, Hawn MB, Akin E, Leblanc N. Translational potential of targeting Anoctamin-1-Encoded Calcium-Activated chloride channels in hypertension. Biochem Pharmacol 2022; 206:115320. [PMID: 36279919 DOI: 10.1016/j.bcp.2022.115320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/13/2022] [Accepted: 10/17/2022] [Indexed: 12/14/2022]
Abstract
Calcium-activated chloride channels (CaCC) provide a depolarizing stimulus to a variety of tissues through chloride efflux in response to a rise in internal Ca2+ and voltage. One of these channels, Anoctamin-1 (ANO1 or TMEM16A) is now recognized to play a central role in promoting smooth muscle tone in various types of blood vessels. Its role in hypertension, and thus the therapeutic promise of targeting ANO1, is less straightforward. This review gives an overview of our current knowledge about the potential role ANO1 may play in hypertension within the systemic, portal, and pulmonary vascular systems and the importance of this information when pursuing potential treatment strategies. While the role of ANO1 is well-established in several forms of pulmonary hypertension, its contributions to both the generation of vascular tone and its role in hypertension within the systemic and portal systems are much less clear. This, combined with ANO1's various roles throughout a multitude of tissues throughout the body, command caution when targeting ANO1 as a therapeutic target and may require tissue-selective strategies.
Collapse
Affiliation(s)
- Connor Jimenez
- Department of Pharmacology and Center of Biomedical Research Excellence (COBRE) for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, 1664 North Virginia Street, Reno, Nevada 89557, USA
| | - Matthew B Hawn
- Department of Pharmacology and Center of Biomedical Research Excellence (COBRE) for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, 1664 North Virginia Street, Reno, Nevada 89557, USA
| | - Elizabeth Akin
- Department of Pharmacology and Center of Biomedical Research Excellence (COBRE) for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, 1664 North Virginia Street, Reno, Nevada 89557, USA
| | - Normand Leblanc
- Department of Pharmacology and Center of Biomedical Research Excellence (COBRE) for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, 1664 North Virginia Street, Reno, Nevada 89557, USA.
| |
Collapse
|
12
|
DOG1 as an Immunohistochemical Marker of Acinic Cell Carcinoma: A Systematic Review and Meta-Analysis. Int J Mol Sci 2022; 23:ijms23179711. [PMID: 36077107 PMCID: PMC9456024 DOI: 10.3390/ijms23179711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 08/20/2022] [Accepted: 08/24/2022] [Indexed: 12/04/2022] Open
Abstract
DOG1 is a transmembrane protein originally discovered on gastrointestinal stromal tumors and works as a calcium-activated chloride channel protein. There are a limited number of articles on the potential utility of this antibody in the diagnosis of salivary gland tumors in routine practice. In this study, we aimed to investigate the role of DOG1 as an immunohistochemical marker in patients with salivary acinic cell carcinoma (ACC) through meta-analysis. A literature search was performed of the PubMed, Scopus, and Web of Science databases for English-language studies published from January 2010 to September 2021. The literature search revealed 148 articles, of which 20 were included in the study. The overall rate of DOG1 expression in salivary acinic cell carcinoma was 55% (95% CI = 0.43–0.58). Although ACC is a challenging diagnosis, paying careful attention to the cytomorphological features in conjunction with DOG1 immunostaining can help to reach an accurate diagnosis.
Collapse
|
13
|
Philp AR, Miranda F, Gianotti A, Mansilla A, Scudieri P, Musante I, Vega G, Figueroa CD, Galietta LJV, Sarmiento JM, Flores CA. KCa3.1 differentially regulates trachea and bronchi epithelial gene expression in a chronic-asthma mouse model. Physiol Genomics 2022; 54:273-282. [PMID: 35658672 DOI: 10.1152/physiolgenomics.00134.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Ion channels are potentially exploitable as pharmacological targets to treat asthma. This study evaluated the role of KCa3.1 channels, encoded by Kcnn4, in regulating the gene expression of mouse airway epithelium and the development of asthma traits. We used the ovalbumin (OVA) challenge as an asthma model in wild type and Kcnn4-/- mice, performed histological analysis, and measured serum IgE to evaluate asthma traits. We analyzed gene expression of isolated epithelial cells of trachea or bronchi using mRNA sequencing and gene ontology and performed Ussing chamber experiments in mouse trachea to evaluate anion secretion. Gene expression of epithelial cells from mouse airways differed between trachea and bronchi, indicating regional differences in the inflammatory and transepithelial transport properties of proximal and distal airways. We found that Kcnn4 silencing reduced mast cell numbers, mucus, and collagen in the airways, and reduced the amount of epithelial anion secretion in the OVA-challenged animals. Additionally, gene expression was differentially modified in the trachea and bronchi, with Kcnn4 genetic silencing significantly altering the expression of genes involved in the TNF pathway, supporting the potential of KCa3.1 as a therapeutic target for asthma.
Collapse
Affiliation(s)
- Amber R Philp
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Austral University of Chile, Valdivia, Chile
| | - Fernando Miranda
- Departamento de Fisiología, Austral University of Chile, Valdivia, Chile
| | | | - Agustín Mansilla
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Austral University of Chile, Valdivia, Chile
| | | | | | - Génesis Vega
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile
| | | | - Luis J V Galietta
- TIGEM, Pozzuoli, Italia.,Department of Translational Medical Sciences, University of Naples Federico II, Naples, Italy
| | - José M Sarmiento
- Departamento de Fisiología, Austral University of Chile, Valdivia, Chile
| | - Carlos A Flores
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Universidad San Sebastián, Valdivia, Chile
| |
Collapse
|
14
|
Galietta LJ. TMEM16A (ANO1) as a therapeutic target in cystic fibrosis. Curr Opin Pharmacol 2022; 64:102206. [DOI: 10.1016/j.coph.2022.102206] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 01/02/2023]
|
15
|
Keely SJ, Barrett KE. Intestinal secretory mechanisms and diarrhea. Am J Physiol Gastrointest Liver Physiol 2022; 322:G405-G420. [PMID: 35170355 PMCID: PMC8917926 DOI: 10.1152/ajpgi.00316.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 01/31/2023]
Abstract
One of the primary functions of the intestinal epithelium is to transport fluid and electrolytes to and from the luminal contents. Under normal circumstances, absorptive and secretory processes are tightly regulated such that absorption predominates, thereby enabling conservation of the large volumes of water that pass through the intestine each day. However, in conditions of secretory diarrhea, this balance becomes dysregulated, so that fluid secretion, driven primarily by Cl- secretion, overwhelms absorptive capacity, leading to increased loss of water in the stool. Secretory diarrheas are common and include those induced by pathogenic bacteria and viruses, allergens, and disruptions to bile acid homeostasis, or as a side effect of many drugs. Here, we review the cellular and molecular mechanisms by which Cl- and fluid secretion in the intestine are regulated, how these mechanisms become dysregulated in conditions of secretory diarrhea, currently available and emerging therapeutic approaches, and how new strategies to exploit intestinal secretory mechanisms are successfully being used in the treatment of constipation.
Collapse
Affiliation(s)
- Stephen J Keely
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, University of Medicine and Health Sciences, Dublin, Ireland
| | - Kim E Barrett
- Department of Medicine, School of Medicine, University of California San Diego, La Jolla, California
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, Davis, California
| |
Collapse
|
16
|
Wang Y, Hu X, Huang H, Jin Z, Gao J, Guo Y, Zhong Y, Li Z, Zong X, Wang K, Zhang L, Liu Z. Optimization of 4-arylthiophene-3-carboxylic acid derivatives as inhibitors of ANO1: Lead optimization studies toward their analgesic efficacy for inflammatory pain. Eur J Med Chem 2022; 237:114413. [DOI: 10.1016/j.ejmech.2022.114413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 04/17/2022] [Accepted: 04/21/2022] [Indexed: 11/04/2022]
|
17
|
Melnik LI, Garry RF. Enterotoxigenic Escherichia coli Heat-Stable Toxin and Ebola Virus Delta Peptide: Similarities and Differences. Pathogens 2022; 11:pathogens11020170. [PMID: 35215114 PMCID: PMC8878840 DOI: 10.3390/pathogens11020170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 01/22/2022] [Accepted: 01/24/2022] [Indexed: 01/27/2023] Open
Abstract
Enterotoxigenic Escherichia coli (ETEC) STb toxin exhibits striking structural similarity to Ebola virus (EBOV) delta peptide. Both ETEC and EBOV delta peptide are enterotoxins. Comparison of the structural and functional similarities and differences of these two toxins illuminates features that are important in induction of pathogenesis by a bacterial and viral pathogen.
Collapse
Affiliation(s)
- Lilia I. Melnik
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA;
- Viral Hemorrhagic Fever Consortium, New Orleans, LA 70112, USA
- Correspondence: ; Tel.: +1-(504)988-3818
| | - Robert F. Garry
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA;
- Viral Hemorrhagic Fever Consortium, New Orleans, LA 70112, USA
| |
Collapse
|
18
|
Melnik LI, Guha S, Ghimire J, Smither AR, Beddingfield BJ, Hoffmann AR, Sun L, Ungerleider NA, Baddoo MC, Flemington EK, Gallaher WR, Wimley WC, Garry RF. Ebola virus delta peptide is an enterotoxin. Cell Rep 2022; 38:110172. [PMID: 34986351 DOI: 10.1016/j.celrep.2021.110172] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/27/2021] [Accepted: 12/03/2021] [Indexed: 12/21/2022] Open
Abstract
During the 2013-2016 West African (WA) Ebola virus (EBOV) outbreak, severe gastrointestinal symptoms were common in patients and associated with poor outcome. Delta peptide is a conserved product of post-translational processing of the abundant EBOV soluble glycoprotein (sGP). The murine ligated ileal loop model was used to demonstrate that delta peptide is a potent enterotoxin. Dramatic intestinal fluid accumulation follows injection of biologically relevant amounts of delta peptide into ileal loops, along with gross alteration of villous architecture and loss of goblet cells. Transcriptomic analyses show that delta peptide triggers damage response and cell survival pathways and downregulates expression of transporters and exchangers. Induction of diarrhea by delta peptide occurs via cellular damage and regulation of genes that encode proteins involved in fluid secretion. While distinct differences exist between the ileal loop murine model and EBOV infection in humans, these results suggest that delta peptide may contribute to EBOV-induced gastrointestinal pathology.
Collapse
Affiliation(s)
- Lilia I Melnik
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Shantanu Guha
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Jenisha Ghimire
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Allison R Smither
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Brandon J Beddingfield
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Andrew R Hoffmann
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Leisheng Sun
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | | | - Melody C Baddoo
- Tulane Cancer Center, Tulane University, New Orleans, LA 70112, USA
| | | | - William R Gallaher
- Department of Microbiology, Immunology and Parasitology, LSU Health Sciences Center, New Orleans, LA 70112, USA; Mockingbird Nature Research Group, Pearl River, LA 70452, USA
| | - William C Wimley
- Department of Biochemistry and Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA.
| | - Robert F Garry
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, LA 70112, USA; Zalgen Labs, Germantown, MD 20876, USA.
| |
Collapse
|
19
|
Pinto MC, Botelho HM, Silva IAL, Railean V, Neumann B, Pepperkok R, Schreiber R, Kunzelmann K, Amaral MD. Systems Approaches to Unravel Molecular Function: High-content siRNA Screen Identifies TMEM16A Traffic Regulators as Potential Drug Targets for Cystic Fibrosis. J Mol Biol 2022; 434:167436. [PMID: 34990652 DOI: 10.1016/j.jmb.2021.167436] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/28/2021] [Accepted: 12/28/2021] [Indexed: 11/25/2022]
Abstract
An attractive approach to treat people with Cystic Fibrosis (CF), a life-shortening disease caused by mutant CFTR, is to compensate for the absence of this chloride/bicarbonate channel by activating alternative (non-CFTR) chloride channels. One obvious target for such "mutation-agnostic" therapeutic approach is TMEM16A (anoctamin-1/ANO1), a calcium-activated chloride channel (CaCC) which is also expressed in the airways of people with CF, albeit at low levels. To find novel TMEM16A regulators of both traffic and function, with the main goal of identifying candidate CF drug targets, we performed a fluorescence cell-based high-throughput siRNA microscopy screen for TMEM16A trafficking using a double-tagged construct expressed in human airway cells. About 700 genes were screened (2 siRNAs per gene) of which 262 were identified as candidate TMEM16A modulators (179 siRNAs enhanced and 83 decreased TMEM16A traffic), being G-protein coupled receptors (GPCRs) enriched on the primary hit list. Among the 179 TMEM16A traffic enhancer siRNAs subjected to secondary screening 20 were functionally validated. Further hit validation revealed that siRNAs targeting two GPCRs - ADRA2C and CXCR3 - increased TMEM16A-mediated chloride secretion in human airway cells, while their overexpression strongly diminished calcium-activated chloride currents in the same cell model. The knockdown, and likely also the inhibition, of these two TMEM16A modulators is therefore an attractive potential therapeutic strategy to increase chloride secretion in CF.
Collapse
Affiliation(s)
- Madalena C Pinto
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande, C8, 1749-016 Lisboa, Portugal. https://twitter.com/madalenacfpinto
| | - Hugo M Botelho
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande, C8, 1749-016 Lisboa, Portugal
| | - Iris A L Silva
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande, C8, 1749-016 Lisboa, Portugal
| | - Violeta Railean
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande, C8, 1749-016 Lisboa, Portugal
| | - Beate Neumann
- Cell Biology/Biophysics Unit, and ALMF, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Rainer Pepperkok
- Cell Biology/Biophysics Unit, and ALMF, European Molecular Biology Laboratory (EMBL), 69117 Heidelberg, Germany
| | - Rainer Schreiber
- Institut für Physiologie, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Karl Kunzelmann
- Institut für Physiologie, University of Regensburg, Universitätsstraße 31, D-93053 Regensburg, Germany
| | - Margarida D Amaral
- BioISI - Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, Campo Grande, C8, 1749-016 Lisboa, Portugal.
| |
Collapse
|
20
|
Abstract
Fluid secretion by exocrine glandular organs is essential to the survival of mammals. Each glandular unit within the body is uniquely organized to carry out its own specific functions, with failure to establish these specialized structures resulting in impaired organ function. Here, we review glandular organs in terms of shared and divergent architecture. We first describe the structural organization of the diverse glandular secretory units (the end-pieces) and their fluid transporting systems (the ducts) within the mammalian system, focusing on how tissue architecture corresponds to functional output. We then highlight how defects in development of end-piece and ductal architecture impacts secretory function. Finally, we discuss how knowledge of exocrine gland structure-function relationships can be applied to the development of new diagnostics, regenerative approaches and tissue regeneration.
Collapse
Affiliation(s)
- Sameed Khan
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Sarah Fitch
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| | - Sarah Knox
- Department of Cell and Tissue Biology, University of California, San Francisco, CA 94143, USA
| | - Ripla Arora
- Department of Obstetrics Gynecology and Reproductive Biology, Michigan State University, East Lansing, MI 48824, USA
- Institute for Quantitative Health Science and Engineering, Michigan State University, East Lansing, MI 48824, USA
| |
Collapse
|
21
|
Li XL, Liu J, Chen XS, Cheng LM, Liu WL, Chen XF, Li YJ, Guan YY, Zeng X, Du YH. Blockade of TMEM16A protects against renal fibrosis by reducing intracellular Cl - concentration. Br J Pharmacol 2021; 179:3043-3060. [PMID: 34961937 DOI: 10.1111/bph.15786] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 09/27/2021] [Accepted: 12/16/2021] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Renal fibrosis is the final common outcome in most forms of CKD. However, the underlying causal mechanisms remain obscure. The present study examined whether TMEM16A, a Ca2+ -activated chloride channel, contributes to the progress of renal fibrosis. EXPERIMENTAL APPROACH Masson staining, western blot and immunohistochemistry were used to measure renal fibrosis and related proteins expression. MQAE was used to evaluate the intracellular Cl- concentration. KEY RESULTS TMEM16A expression was significantly upregulated in fibrotic kidneys of unilateral ureteral obstruction (UUO) and high-fat diet murine models, and in renal samples of IgA nephropathy patients. In vivo knockdown of TMEM16A with adenovirus harboring TMEM16A-shRNA or inhibition of TMEM16A channel activity with its specific inhibitor CaCCinh-A01 or T16Ainh-A01 effectively prevented UUO-induced renal fibrosis and decreased protein expression of fibronectin, α-SMA and collagen in the obstructed kidneys. In cultured HK2 cells, knockdown or inhibition of TMEM16A suppressed TGF-β1-induced epithelial to mesenchymal transition, reduced snail1 expression and phosphorylation of Smad2/3 and ERK1/2, whereas overexpression of TMEM16A showed the opposite effects. TGF-β1 increased [Cl- ]i in HK2 cells, which was inhibited by knockdown or inhibition of TMEM16A. Reducing [Cl- ]i by low Cl- culture medium significantly blunted TGF-β1-induced Smad2/3 phosphorylation and profibrotic factors expression. The profibrotic effects of TGF-β1 were also abrogated by the inhibitor of SGK1, a kinase whose activity was also suppressed by reducing [Cl- ]i. CONCLUSION AND IMPLICATIONS Blockade of TMEM16A prevented the progression of kidney fibrosis, likely by suppressing [Cl- ]i/SGK1/TGF-β1 signaling pathway. TMEM16A may be a potential new therapeutic target against renal fibrosis.
Collapse
Affiliation(s)
- Xiao-Long Li
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Jing Liu
- Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiao-Shan Chen
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Li-Min Cheng
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Wei-Ling Liu
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xing-Feng Chen
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Yue-Jiao Li
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Yong-Yuan Guan
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Xin Zeng
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| | - Yan-Hua Du
- Department of Pharmacology, Cardiac & Cerebral Vascular Research Center, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, Guangdong, China
| |
Collapse
|
22
|
Hawn MB, Akin E, Hartzell H, Greenwood IA, Leblanc N. Molecular mechanisms of activation and regulation of ANO1-Encoded Ca 2+-Activated Cl - channels. Channels (Austin) 2021; 15:569-603. [PMID: 34488544 PMCID: PMC8480199 DOI: 10.1080/19336950.2021.1975411] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 08/29/2021] [Indexed: 01/13/2023] Open
Abstract
Ca2+-activated Cl- channels (CaCCs) perform a multitude of functions including the control of cell excitability, regulation of cell volume and ionic homeostasis, exocrine and endocrine secretion, fertilization, amplification of olfactory sensory function, and control of smooth muscle cell contractility. CaCCs are the translated products of two members (ANO1 and ANO2, also known as TMEM16A and TMEM16B) of the Anoctamin family of genes comprising ten paralogs. This review focuses on recent progress in understanding the molecular mechanisms involved in the regulation of ANO1 by cytoplasmic Ca2+, post-translational modifications, and how the channel protein interacts with membrane lipids and protein partners. After first reviewing the basic properties of native CaCCs, we then present a brief historical perspective highlighting controversies about their molecular identity in native cells. This is followed by a summary of the fundamental biophysical and structural properties of ANO1. We specifically address whether the channel is directly activated by internal Ca2+ or indirectly through the intervention of the Ca2+-binding protein Calmodulin (CaM), and the structural domains responsible for Ca2+- and voltage-dependent gating. We then review the regulation of ANO1 by internal ATP, Calmodulin-dependent protein kinase II-(CaMKII)-mediated phosphorylation and phosphatase activity, membrane lipids such as the phospholipid phosphatidyl-(4,5)-bisphosphate (PIP2), free fatty acids and cholesterol, and the cytoskeleton. The article ends with a survey of physical and functional interactions of ANO1 with other membrane proteins such as CLCA1/2, inositol trisphosphate and ryanodine receptors in the endoplasmic reticulum, several members of the TRP channel family, and the ancillary Κ+ channel β subunits KCNE1/5.
Collapse
Affiliation(s)
- M. B. Hawn
- Department of Pharmacology and Center of Biomedical Research Excellence for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, Reno, United States
| | - E. Akin
- Department of Pharmacology and Center of Biomedical Research Excellence for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, Reno, United States
| | - H.C. Hartzell
- Department of Cell Biology, Emory University School of Medicine, USA
| | - I. A. Greenwood
- Department of Vascular Pharmacology, St. George’s University of London, UK
| | - N. Leblanc
- Department of Pharmacology and Center of Biomedical Research Excellence for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, Reno, United States
| |
Collapse
|
23
|
Saha T, Aoun J, Sarkar P, Bourdelais AJ, Baden DG, Leblanc N, Hamlyn JM, Woodward OM, Hoque KM. Cucumis sativus extract elicits chloride secretion by stimulation of the intestinal TMEM16A ion channel. PHARMACEUTICAL BIOLOGY 2021; 59:1008-1015. [PMID: 34362288 PMCID: PMC8354179 DOI: 10.1080/13880209.2021.1949357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 06/03/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
CONTEXT Cucumber (Cucumis sativus Linn. [Cucurbitaceae]) is widely known for its purgative, antidiabetic, antioxidant, and anticancer therapeutic potential. However, its effect on gastrointestinal (GI) disease is unrecognised. OBJECTIVE This study investigated the effect of C. sativus fruit extract (CCE) on intestinal chloride secretion, motility, and motor function, and the role of TMEM16A chloride channels. MATERIALS AND METHODS CCE extracts were obtained from commercially available cucumber. Active fractions were then purified by HPLC and analysed by high resolution mass spectrometry. The effect of CCE on intestinal chloride secretion was investigated in human colonic T84 cells, ex vivo mouse intestinal tissue using an Ussing chamber, and the two-electrode voltage-clamp technique to record calcium sensitive TMEM16A chloride currents in Xenopus laevis oocytes. In vivo, intestinal motility was investigated using the loperamide-induced C57BL/6 constipation mouse model. Ex vivo contractility of mouse colonic smooth muscles was assessed by isometric force measurements. RESULTS CCE increased the short-circuit current (ΔIsc 34.47 ± µA/cm2) and apical membrane chloride conductance (ΔICl 95 ± 8.1 µA/cm2) in intestinal epithelial cells. The effect was dose-dependent, with an EC50 value of 0.06 µg/mL. CCE stimulated the endogenous TMEM16A-induced Cl- current in Xenopus laevis oocytes. Moreover, CCE increased the contractility of smooth muscle in mouse colonic tissue and enhanced small bowel transit in CCE treated mice compared to loperamide controls. Mass spectrometry suggested a cucurbitacin-like analogue with a mass of 512.07 g/mol underlying the bioactivity of CCE. CONCLUSION A cucurbitacin-like analog present in CCE activates TMEM16A channels, which may have therapeutic potential in cystic fibrosis and intestinal hypodynamic disorders.
Collapse
Affiliation(s)
- Tultul Saha
- Pathophysiology Division, National Institute of Cholera & Enteric Diseases, Kolkata, India
| | - Joydeep Aoun
- Pathophysiology Division, National Institute of Cholera & Enteric Diseases, Kolkata, India
- Department of Pharmacology, The Center for Cardiovascular Research, Center of Biomedical Research Excellence for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - Paramita Sarkar
- Pathophysiology Division, National Institute of Cholera & Enteric Diseases, Kolkata, India
| | | | - Daniel G. Baden
- Center for Marine Science, University of North Carolina, Wilmington, NC, USA
| | - Normand Leblanc
- Department of Pharmacology, The Center for Cardiovascular Research, Center of Biomedical Research Excellence for Molecular and Cellular Signal Transduction in the Cardiovascular System, University of Nevada, Reno School of Medicine, Reno, NV, USA
| | - John M. Hamlyn
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Owen M. Woodward
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kazi Mirajul Hoque
- Pathophysiology Division, National Institute of Cholera & Enteric Diseases, Kolkata, India
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
24
|
Huizinga JD, Hussain A, Chen JH. Interstitial cells of Cajal and human colon motility in health and disease. Am J Physiol Gastrointest Liver Physiol 2021; 321:G552-G575. [PMID: 34612070 DOI: 10.1152/ajpgi.00264.2021] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Our understanding of human colonic motility, and autonomic reflexes that generate motor patterns, has increased markedly through high-resolution manometry. Details of the motor patterns are emerging related to frequency and propagation characteristics that allow linkage to interstitial cells of Cajal (ICC) networks. In studies on colonic motor dysfunction requiring surgery, ICC are almost always abnormal or significantly reduced. However, there are still gaps in our knowledge about the role of ICC in the control of colonic motility and there is little understanding of a mechanistic link between ICC abnormalities and colonic motor dysfunction. This review will outline the various ICC networks in the human colon and their proven and likely associations with the enteric and extrinsic autonomic nervous systems. Based on our extensive knowledge of the role of ICC in the control of gastrointestinal motility of animal models and the human stomach and small intestine, we propose how ICC networks are underlying the motor patterns of the human colon. The role of ICC will be reviewed in the autonomic neural reflexes that evoke essential motor patterns for transit and defecation. Mechanisms underlying ICC injury, maintenance, and repair will be discussed. Hypotheses are formulated as to how ICC dysfunction can lead to motor abnormalities in slow transit constipation, chronic idiopathic pseudo-obstruction, Hirschsprung's disease, fecal incontinence, diverticular disease, and inflammatory conditions. Recent studies on ICC repair after injury hold promise for future therapies.
Collapse
Affiliation(s)
- Jan D Huizinga
- Division of Gastroenterology, Department of Medicine, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Amer Hussain
- Division of Gastroenterology, Department of Medicine, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - Ji-Hong Chen
- Division of Gastroenterology, Department of Medicine, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| |
Collapse
|
25
|
TMEM16A/ANO1: Current Strategies and Novel Drug Approaches for Cystic Fibrosis. Cells 2021; 10:cells10112867. [PMID: 34831090 PMCID: PMC8616501 DOI: 10.3390/cells10112867] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 12/19/2022] Open
Abstract
Cystic fibrosis (CF) is the most common of rare hereditary diseases in Caucasians, and it is estimated to affect 75,000 patients globally. CF is a complex disease due to the multiplicity of mutations found in the CF transmembrane conductance regulator (CFTR) gene causing the CFTR protein to become dysfunctional. Correctors and potentiators have demonstrated good clinical outcomes for patients with specific gene mutations; however, there are still patients for whom those treatments are not suitable and require alternative CFTR-independent strategies. Although CFTR is the main chloride channel in the lungs, others could, e.g., anoctamin-1 (ANO1 or TMEM16A), compensate for the deficiency of CFTR. This review summarizes the current knowledge on calcium-activated chloride channel (CaCC) ANO1 and presents ANO1 as an exciting target in CF.
Collapse
|
26
|
Bai W, Liu M, Xiao Q. The diverse roles of TMEM16A Ca 2+-activated Cl - channels in inflammation. J Adv Res 2021; 33:53-68. [PMID: 34603778 PMCID: PMC8463915 DOI: 10.1016/j.jare.2021.01.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/17/2020] [Accepted: 01/24/2021] [Indexed: 12/14/2022] Open
Abstract
Background Transmembrane protein 16A (TMEM16A) Ca2+-activated Cl- channels have diverse physiological functions, such as epithelial secretion of Cl- and fluid and sensation of pain. Recent studies have demonstrated that TMEM16A contributes to the pathogenesis of infectious and non-infectious inflammatory diseases. However, the role of TMEM16A in inflammation has not been clearly elucidated. Aim of review In this review, we aimed to provide comprehensive information regarding the roles of TMEM16A in inflammation by summarizing the mechanisms underlying TMEM16A expression and activation under inflammatory conditions, in addition to exploring the diverse inflammatory signaling pathways activated by TMEM16A. This review attempts to develop the idea that TMEM16A plays a diverse role in inflammatory processes and contributes to inflammatory diseases in a cellular environment-dependent manner. Key scientific concepts of review Multiple inflammatory mediators, including cytokines (e.g., interleukin (IL)-4, IL-13, IL-6), histamine, bradykinin, and ATP/UTP, as well as bacterial and viral infections, promote TMEM16A expression and/or activity under inflammatory conditions. In addition, TMEM16A activates diverse inflammatory signaling pathways, including the IP3R-mediated Ca2+ signaling pathway, the NF-κB signaling pathway, and the ERK signaling pathway, and contributes to the pathogenesis of many inflammatory diseases. These diseases include airway inflammatory diseases, lipopolysaccharide-induced intestinal epithelial barrier dysfunction, acute pancreatitis, and steatohepatitis. TMEM16A also plays multiple roles in inflammatory processes by increasing vascular permeability and leukocyte adhesion, promoting inflammatory cytokine release, and sensing inflammation-induced pain. Furthermore, TMEM16A plays its diverse pathological roles in different inflammatory diseases depending on the disease severity, proliferating status of the cells, and its interacting partners. We herein propose cellular environment-dependent mechanisms that explain the diverse roles of TMEM16A in inflammation.
Collapse
Affiliation(s)
- Weiliang Bai
- Department of Otolaryngology Head and Neck Surgery, Shengjing Hospital of China Medical University, Shenyang 110004, China
| | - Mei Liu
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Qinghuan Xiao
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| |
Collapse
|
27
|
Abstract
TMEM16A Ca2+-activated chloride channels are involved in multiple cellular functions and are proposed targets for diseases such as hypertension, stroke, and cystic fibrosis. This therapeutic endeavor, however, suffers from paucity of selective and potent modulators. Here, exploiting a synthetic small molecule with a biphasic effect on the TMEM16A channel, anthracene-9-carboxylic acid (A9C), we shed light on sites of the channel amenable for pharmacological intervention. Mutant channels with the intracellular gate constitutively open were generated. These channels were entirely insensitive to extracellular A9C when intracellular Ca2+ was omitted. However, when physiological Ca2+ levels were reestablished, the mutants regained sensitivity to A9C. Thus, intracellular Ca2+ is mandatory for the channel response to an extracellular modulator. The underlying mechanism is a conformational change in the outer pore that enables A9C to enter the pore to reach its binding site. The explanation of this structural rearrangement highlights a critical site for pharmacological intervention and reveals an aspect of Ca2+ gating in the TMEM16A channel.
Collapse
|
28
|
Diszházi G, Magyar ZÉ, Lisztes E, Tóth-Molnár E, Nánási PP, Vennekens R, Tóth BI, Almássy J. TRPM4 links calcium signaling to membrane potential in pancreatic acinar cells. J Biol Chem 2021; 297:101015. [PMID: 34329682 PMCID: PMC8371206 DOI: 10.1016/j.jbc.2021.101015] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 07/22/2021] [Accepted: 07/26/2021] [Indexed: 01/02/2023] Open
Abstract
Transient receptor potential cation channel subfamily M member 4 (TRPM4) is a Ca2+-activated nonselective cation channel that mediates membrane depolarization. Although, a current with the hallmarks of a TRPM4-mediated current has been previously reported in pancreatic acinar cells (PACs), the role of TRPM4 in the regulation of acinar cell function has not yet been explored. In the present study, we identify this TRPM4 current and describe its role in context of Ca2+ signaling of PACs using pharmacological tools and TRPM4-deficient mice. We found a significant Ca2+-activated cation current in PACs that was sensitive to the TRPM4 inhibitors 9-phenanthrol and 4-chloro-2-[[2-(2-chlorophenoxy)acetyl]amino]benzoic acid (CBA). We demonstrated that the CBA-sensitive current was responsible for a Ca2+-dependent depolarization of PACs from a resting membrane potential of −44.4 ± 2.9 to −27.7 ± 3 mV. Furthermore, we showed that Ca2+ influx was higher in the TRPM4 KO- and CBA-treated PACs than in control cells. As hormone-induced repetitive Ca2+ transients partially rely on Ca2+ influx in PACs, the role of TRPM4 was also assessed on Ca2+ oscillations elicited by physiologically relevant concentrations of the cholecystokinin analog cerulein. These data show that the amplitude of Ca2+ signals was significantly higher in TRPM4 KO than in control PACs. Our results suggest that PACs are depolarized by TRPM4 currents to an extent that results in a significant reduction of the inward driving force for Ca2+. In conclusion, TRPM4 links intracellular Ca2+ signaling to membrane potential as a negative feedback regulator of Ca2+ entry in PACs.
Collapse
Affiliation(s)
- Gyula Diszházi
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Zsuzsanna É Magyar
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Erika Lisztes
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Edit Tóth-Molnár
- Department of Ophthalmology, University of Szeged, Szeged, Hungary
| | - Péter P Nánási
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Rudi Vennekens
- Laboratory of Ion Channel Research, Department of Cellular and Molecular Medicine, Faculty of Medicine, TRP Research Platform Leuven, VIB Center for Brain and Disease Research, KU Leuven, Leuven, Belgium
| | - Balázs I Tóth
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - János Almássy
- Department of Physiology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.
| |
Collapse
|
29
|
Pinto MC, Silva IAL, Figueira MF, Amaral MD, Lopes-Pacheco M. Pharmacological Modulation of Ion Channels for the Treatment of Cystic Fibrosis. J Exp Pharmacol 2021; 13:693-723. [PMID: 34326672 PMCID: PMC8316759 DOI: 10.2147/jep.s255377] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/30/2021] [Indexed: 12/12/2022] Open
Abstract
Cystic fibrosis (CF) is a life-shortening monogenic disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein, an anion channel that transports chloride and bicarbonate across epithelia. Despite clinical progress in delaying disease progression with symptomatic therapies, these individuals still develop various chronic complications in lungs and other organs, which significantly restricts their life expectancy and quality of life. The development of high-throughput assays to screen drug-like compound libraries have enabled the discovery of highly effective CFTR modulator therapies. These novel therapies target the primary defect underlying CF and are now approved for clinical use for individuals with specific CF genotypes. However, the clinically approved modulators only partially reverse CFTR dysfunction and there is still a considerable number of individuals with CF carrying rare CFTR mutations who remain without any effective CFTR modulator therapy. Accordingly, additional efforts have been pursued to identify novel and more potent CFTR modulators that may benefit a larger CF population. The use of ex vivo individual-derived specimens has also become a powerful tool to evaluate novel drugs and predict their effectiveness in a personalized medicine approach. In addition to CFTR modulators, pro-drugs aiming at modulating alternative ion channels/transporters are under development to compensate for the lack of CFTR function. These therapies may restore normal mucociliary clearance through a mutation-agnostic approach (ie, independent of CFTR mutation) and include inhibitors of the epithelial sodium channel (ENaC), modulators of the calcium-activated channel transmembrane 16A (TMEM16, or anoctamin 1) or of the solute carrier family 26A member 9 (SLC26A9), and anionophores. The present review focuses on recent progress and challenges for the development of ion channel/transporter-modulating drugs for the treatment of CF.
Collapse
Affiliation(s)
- Madalena C Pinto
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Iris A L Silva
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miriam F Figueira
- Marsico Lung Institute/Cystic Fibrosis Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| |
Collapse
|
30
|
Lee HJ, Donati A, Feliers D, Sun Y, Ding Y, Madesh M, Salmon AB, Ikeno Y, Ross C, O'Connor CL, Ju W, Bitzer M, Chen Y, Choudhury GG, Singh BB, Sharma K, Kasinath BS. Chloride channel accessory 1 integrates chloride channel activity and mTORC1 in aging-related kidney injury. Aging Cell 2021; 20:e13407. [PMID: 34118180 PMCID: PMC8282273 DOI: 10.1111/acel.13407] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 03/30/2021] [Accepted: 05/08/2021] [Indexed: 12/19/2022] Open
Abstract
The mechanism of kidney injury in aging are not well understood. In order to identify hitherto unknown pathways of aging‐related kidney injury, we performed RNA‐Seq on kidney extracts of young and aged mice. Expression of chloride (Cl) channel accessory 1 (CLCA1) mRNA and protein was increased in the kidneys of aged mice. Immunostaining showed a marked increase in CLCLA1 expression in the proximal tubules of the kidney from aged mice. Increased kidney CLCA1 gene expression also correlated with aging in marmosets and in a human cohort. In aging mice, increased renal cortical CLCA1 content was associated with hydrogen sulfide (H2S) deficiency, which was ameliorated by administering sodium hydrosulfide (NaHS), a source of H2S. In order to study whether increased CLCA1 expression leads to injury phenotype and the mechanisms involved, stable transfection of proximal tubule epithelial cells overexpressing human CLCA1 (hCLCA1) was performed. Overexpression of hCLCA1 augmented Cl− current via the Ca++‐dependent Cl− channel TMEM16A (anoctamin‐1) by patch‐clamp studies. hCLCA1 overexpression also increased the expression of fibronectin, a matrix protein, and induced the senescence‐associated secretory phenotype (SASP). Mechanistic studies underlying these changes showed that hCLCA1 overexpression leads to inhibition of AMPK activity and stimulation of mTORC1 as cellular signaling determinants of injury. Both TMEM16A inhibitor and NaHS reversed these signaling events and prevented changes in fibronectin and SASP. We conclude that CLCA1‐TMEM16A‐Cl− current pathway is a novel mediator of kidney injury in aging that is regulated by endogenous H2S.
Collapse
Affiliation(s)
- Hak Joo Lee
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
| | - Andrew Donati
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
| | - Denis Feliers
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
| | - Yuyang Sun
- Department of Periodontics University of Texas Health San Antonio TX USA
| | - Yanli Ding
- Department of Pathology University of Texas Health San Antonio TX USA
| | - Muniswamy Madesh
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
| | - Adam B. Salmon
- Department of Molecular Medicine University of Texas Health San Antonio TX USA
- Barshop Institute for Longevity and Aging Studies University of Texas Health San Antonio TX USA
- South Texas Veterans Health Care System San Antonio TX USA
- Geriatric Research Education & Clinical Center South Texas Veterans Health Care System San Antonio TX USA
| | - Yuji Ikeno
- Department of Pathology University of Texas Health San Antonio TX USA
- Department of Molecular Medicine University of Texas Health San Antonio TX USA
- South Texas Veterans Health Care System San Antonio TX USA
| | - Corinna Ross
- Texas Biomedical Research Institute Southwest National Primate Research Center San Antonio TX USA
- Department of Science and Mathematics Texas A&M University San Antonio San Antonio TX USA
| | | | - Wenjun Ju
- Department of Internal Medicine University of Michigan Ann Arbor MI USA
| | - Markus Bitzer
- Department of Internal Medicine University of Michigan Ann Arbor MI USA
| | - Yidong Chen
- Department of Population Health Sciences University of Texas Health San Antonio TX USA
- Greehey Children's Cancer Research Institute University of Texas Health San Antonio TX USA
| | - Goutam Ghosh Choudhury
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
- South Texas Veterans Health Care System San Antonio TX USA
- Geriatric Research Education & Clinical Center South Texas Veterans Health Care System San Antonio TX USA
| | - Brij B. Singh
- Department of Periodontics University of Texas Health San Antonio TX USA
| | - Kumar Sharma
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
- South Texas Veterans Health Care System San Antonio TX USA
| | - Balakuntalam S. Kasinath
- Department of Medicine Center for Renal Precision Medicine University of Texas Health San Antonio TX USA
- Barshop Institute for Longevity and Aging Studies University of Texas Health San Antonio TX USA
- South Texas Veterans Health Care System San Antonio TX USA
- Geriatric Research Education & Clinical Center South Texas Veterans Health Care System San Antonio TX USA
| |
Collapse
|
31
|
Wang Y, Gao J, Zhao S, Song Y, Huang H, Zhu G, Jiao P, Xu X, Zhang G, Wang K, Zhang L, Liu Z. Discovery of 4-arylthiophene-3-carboxylic acid as inhibitor of ANO1 and its effect as analgesic agent. Acta Pharm Sin B 2021; 11:1947-1964. [PMID: 34386330 PMCID: PMC8343189 DOI: 10.1016/j.apsb.2020.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Revised: 10/26/2020] [Accepted: 11/04/2020] [Indexed: 02/05/2023] Open
Abstract
Anoctamin 1 (ANO1) is a kind of calcium-activated chloride channel involved in nerve depolarization. ANO1 inhibitors display significant analgesic activity by the local peripheral and intrathecal administration. In this study, several thiophenecarboxylic acid and benzoic acid derivatives were identified as novel ANO1 inhibitors through the shape-based virtual screening, among which the 4-arylthiophene-3-carboxylic acid analogues with the best ANO1 inhibitory activity were designed, synthesized and compound 42 (IC50 = 0.79 μmol/L) was finally obtained. Compound 42 selectively inhibited ANO1 without affecting ANO2 and intracellular Ca2+ concentration. Subsequently, the analgesic effect was investigated by intragastric administration in pain models. Compound 42 significantly attenuated allodynia which was induced by formalin and chronic constriction injury. Through homology modeling and molecular dynamics, the binding site was predicted to be located near the calcium-binding region between α6 and α8. Our study validates ANO1 inhibitors having a significant analgesic effect by intragastric administration and also provides selective molecular tools for ANO1-related research.
Collapse
|
32
|
Constable PA, Kapoor G. Is white the right light for the clinical electrooculogram? Doc Ophthalmol 2021; 143:297-304. [PMID: 34160736 DOI: 10.1007/s10633-021-09845-9] [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: 04/13/2021] [Accepted: 06/14/2021] [Indexed: 11/30/2022]
Abstract
PURPOSE To investigate if a lower luminance monochromatic LED stimulus could be used as an alternative to a high luminance white light for the clinical electrooculogram. METHODS Clinical electrooculograms were recorded in color normal participants (N = 23) aged 22.6 ± 1.2 years, 7 male and 16 female using the standard 100 cd.m-2 white illuminant and four monochromatic LEDs with peak wavelengths of 448, 534, 596 and 634 nm at 30 cd.m-2. Pupils were dilated and there was a 30 cd.m-2pre-adaptation to white light for 2 min followed by 15 min dark adaptation and 20 min recording in the light stimulus using a Ganzfeld stimulator. RESULTS The normalized LP:DTratio for the short wavelength LED (448 nm) was equivalent in amplitude and timing to the ISCEV standard EOG (p = .99). The LP:DTratio for the white (100 cd.m-2) and 448 nm (30 cd.m-2) were (median ± SEM): 2.49 ± .11 and 2.47 ± .11. The time to light-rise peak was also equivalent being 9.0 ± .2 and 8.0 ± .4 min (p = .54). CONCLUSIONS Consideration may be given to using a short wavelength monochromatic stimulus that is more comfortable for the subject than the current 100 cd.m-2 illuminant.
Collapse
Affiliation(s)
- Paul A Constable
- Caring Futures Institute, College of Nursing and Health Sciences, Flinders University, PO Box 2100, Adelaide, SA, 5001, Australia.
| | - Garima Kapoor
- College of Medicine and Public Health, Flinders University, Adelaide, Australia
| |
Collapse
|
33
|
Liu Y, Liu Z, Wang K. The Ca 2+-activated chloride channel ANO1/TMEM16A: An emerging therapeutic target for epithelium-originated diseases? Acta Pharm Sin B 2021; 11:1412-1433. [PMID: 34221860 PMCID: PMC8245819 DOI: 10.1016/j.apsb.2020.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/19/2020] [Accepted: 09/14/2020] [Indexed: 02/07/2023] Open
Abstract
Anoctamin 1 (ANO1) or TMEM16A gene encodes a member of Ca2+ activated Cl– channels (CaCCs) that are critical for physiological functions, such as epithelial secretion, smooth muscle contraction and sensory signal transduction. The attraction and interest in ANO1/TMEM16A arise from a decade long investigations that abnormal expression or dysfunction of ANO1 is involved in many pathological phenotypes and diseases, including asthma, neuropathic pain, hypertension and cancer. However, the lack of specific modulators of ANO1 has impeded the efforts to validate ANO1 as a therapeutic target. This review focuses on the recent progress made in understanding of the pathophysiological functions of CaCC ANO1 and the current modulators used as pharmacological tools, hopefully illustrating a broad spectrum of ANO1 channelopathy and a path forward for this target validation.
Collapse
Key Words
- ANO1
- ANO1, anoctamin-1
- ASM, airway smooth muscle
- Ang II, angiotensin II
- BBB, blood–brain barrier
- CAMK, Ca2+/calmodulin-dependent protein kinase
- CF, cystic fibrosis
- CFTR, cystic fibrosis transmembrane conductance regulator
- Ca2+-activated Cl– channels (CaCCs)
- CaCCinh-A01
- CaCCs, Ca2+ activated chloride channels
- Cancer
- Cystic fibrosis
- DRG, dorsal root ganglion
- Drug target
- EGFR, epidermal growth factor receptor
- ENaC, epithelial sodium channels
- ER, endoplasmic reticulum
- ESCC, esophageal squamous cell carcinoma
- FRT, fisher rat thyroid
- GI, gastrointestinal
- GIST, gastrointestinal stromal tumor
- GPCR, G-protein coupled receptor
- HNSCC, head and neck squamous cell carcinoma
- HTS, high-throughput screening
- ICC, interstitial cells of Cajal
- IPAH, idiopathic pulmonary arterial hypertension
- MAPK, mitogen-activated protein kinase
- NF-κB, nuclear factor κB
- PAH, pulmonary arterial hypertension
- PAR2, protease activated receptor 2
- PASMC, pulmonary artery smooth muscle cells
- PIP2, phosphatidylinositol 4,5-bisphosphate
- PKD, polycystic kidney disease
- T16Ainh-A01
- TGF-β, transforming growth factor-β
- TMEM16A
- VGCC, voltage gated calcium channel
- VRAC, volume regulated anion channel
- VSMC, vascular smooth muscle cells
- YFP, yellow fluorescent protein
Collapse
Affiliation(s)
- Yani Liu
- Department of Pharmacology, School of Pharmacy, Qingdao University Medical College, Qingdao 266073, China
- Institute of Innovative Drugs, Qingdao University, Qingdao 266021, China
| | - Zongtao Liu
- Department of Clinical Laboratory, Qingdao Third People's Hospital, Qingdao 266041, China
| | - KeWei Wang
- Department of Pharmacology, School of Pharmacy, Qingdao University Medical College, Qingdao 266073, China
- Institute of Innovative Drugs, Qingdao University, Qingdao 266021, China
- Corresponding authors.
| |
Collapse
|
34
|
Aritake H, Tamada T, Murakami K, Gamo S, Nara M, Kazama I, Ichinose M, Sugiura H. Effects of indacaterol on the LPS-evoked changes in fluid secretion rate and pH in swine tracheal membrane. Pflugers Arch 2021; 473:883-896. [PMID: 34031755 PMCID: PMC8164627 DOI: 10.1007/s00424-021-02560-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 03/16/2021] [Accepted: 03/23/2021] [Indexed: 11/21/2022]
Abstract
An acquired dysregulation of airway secretion is likely involved in the pathophysiology of chronic bronchitis and chronic obstructive pulmonary disease (COPD). Nowadays, it is widely known that several kinds of long-acting bronchodilators reduce the frequency of COPD exacerbations. However, limited data are available concerning the complementary additive effects on airflow obstruction. Using an optical method and a selective pH indicator, we succeeded in evaluating the gland secretion rate and the pH in swine tracheal membrane. A physiologically relevant concentration of acetylcholine (ACh) 100 nM induced a gradual increase in the amount of gland secretion. Lipopolysaccharides (LPS) accelerated the ACh-induced secretory responses up to around threefold and lowered the pH level significantly. Long-acting β2-agonists (LABAs) including indacaterol (IND), formoterol, and salmeterol restored the LPS-induced changes in both the hypersecretion and acidification. The subsequent addition of the long-acting muscarine antagonist, glycopyrronium, further increased the pH values. Two different inhibitors for cystic fibrosis transmembrane conductance regulator (CFTR), NPPB and CFTRinh172, abolished the IND-mediated pH normalization in the presence of both ACh and ACh + LPS. Both immunofluorescence staining and western blotting analysis revealed that LPS downregulated the abundant expression of CFTR protein. However, IND did not restore the LPS-induced decrease in CFTR expression on Calu-3 cells. These findings suggest that the activation of cAMP-dependent HCO3− secretion through CFTR would be partly involved in the IND-mediated pH normalization in gland secretion and may be suitable for the maintenance of airway defense against exacerbating factors including LPS.
Collapse
Affiliation(s)
- Hidemi Aritake
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan
| | - Tsutomu Tamada
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan.
| | - Koji Murakami
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan
| | - Shunichi Gamo
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan
| | - Masayuki Nara
- National Hospital Organization Akita National Hospital, Yurihonjo, Japan
| | - Itsuro Kazama
- Miyagi University School of Nursing Graduate School of Nursing, Kurokawa-gun, Japan
| | | | - Hisatoshi Sugiura
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, 980-8574, Japan
| |
Collapse
|
35
|
CLCA1 Regulates Airway Mucus Production and Ion Secretion Through TMEM16A. Int J Mol Sci 2021; 22:ijms22105133. [PMID: 34066250 PMCID: PMC8151571 DOI: 10.3390/ijms22105133] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/04/2021] [Accepted: 05/10/2021] [Indexed: 02/07/2023] Open
Abstract
TMEM16A, a Ca2+-activated chloride channel (CaCC), and its regulator, CLCA1, are associated with inflammatory airway disease and goblet cell metaplasia. CLCA1 is a secreted protein with protease activity that was demonstrated to enhance membrane expression of TMEM16A. Expression of CLCA1 is particularly enhanced in goblet cell metaplasia and is associated with various lung diseases. However, mice lacking expression of CLCA1 showed the same degree of mucous cell metaplasia and airway hyperreactivity as asthmatic wild-type mice. To gain more insight into the role of CLCA1, we applied secreted N-CLCA1, produced in vitro, to mice in vivo using intratracheal instillation. We observed no obvious upregulation of TMEM16A membrane expression by CLCA1 and no differences in ATP-induced short circuit currents (Iscs). However, intraluminal mucus accumulation was observed by treatment with N-CLCA1 that was not seen in control animals. The effects of N-CLCA1 were augmented in ovalbumin-sensitized mice. Mucus production induced by N-CLCA1 in polarized BCi-NS1 human airway epithelial cells was dependent on TMEM16A expression. IL-13 upregulated expression of CLCA1 and enhanced mucus production, however, without enhancing purinergic activation of Isc. In contrast to polarized airway epithelial cells and mouse airways, which express very low levels of TMEM16A, nonpolarized airway cells express large amounts of TMEM16A protein and show strong CaCC. The present data show an only limited contribution of TMEM16A to airway ion secretion but suggest a significant role of both CLCA1 and TMEM16A for airway mucus secretion.
Collapse
|
36
|
McMahon DB, Carey RM, Kohanski MA, Adappa ND, Palmer JN, Lee RJ. PAR-2-activated secretion by airway gland serous cells: role for CFTR and inhibition by Pseudomonas aeruginosa. Am J Physiol Lung Cell Mol Physiol 2021; 320:L845-L879. [PMID: 33655758 DOI: 10.1152/ajplung.00411.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Airway submucosal gland serous cells are important sites of fluid secretion in conducting airways. Serous cells also express the cystic fibrosis (CF) transmembrane conductance regulator (CFTR). Protease-activated receptor 2 (PAR-2) is a G protein-coupled receptor that activates secretion from intact airway glands. We tested if and how human nasal serous cells secrete fluid in response to PAR-2 stimulation using Ca2+ imaging and simultaneous differential interference contrast imaging to track isosmotic cell shrinking and swelling reflecting activation of solute efflux and influx pathways, respectively. During stimulation of PAR-2, serous cells exhibited dose-dependent increases in intracellular Ca2+. At stimulation levels >EC50 for Ca2+, serous cells simultaneously shrank ∼20% over ∼90 s due to KCl efflux reflecting Ca2+-activated Cl- channel (CaCC, likely TMEM16A)-dependent secretion. At lower levels of PAR-2 stimulation (<EC50 for Ca2+), shrinkage was not evident due to failure to activate CaCC. Low levels of cAMP-elevating VIP receptor (VIPR) stimulation, also insufficient to activate secretion alone, synergized with low-level PAR-2 stimulation to elicit fluid secretion dependent on both cAMP and Ca2+ to activate CFTR and K+ channels, respectively. Polarized cultures of primary serous cells also exhibited synergistic fluid secretion. Pre-exposure to Pseudomonas aeruginosa conditioned media inhibited PAR-2 activation by proteases but not peptide agonists in primary nasal serous cells, Calu-3 bronchial cells, and primary nasal ciliated cells. Disruption of synergistic CFTR-dependent PAR-2/VIPR secretion may contribute to reduced airway surface liquid in CF. Further disruption of the CFTR-independent component of PAR-2-activated secretion by P. aeruginosa may also be important to CF pathophysiology.
Collapse
Affiliation(s)
- Derek B McMahon
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Ryan M Carey
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Michael A Kohanski
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Nithin D Adappa
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - James N Palmer
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| | - Robert J Lee
- Department of Otorhinolaryngology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania.,Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
| |
Collapse
|
37
|
Shi J, Shi S, Yuan G, Jia Q, Shi S, Zhu X, Zhou Y, Chen T, Hu Y. Bibliometric analysis of chloride channel research (2004-2019). Channels (Austin) 2020; 14:393-402. [PMID: 33103563 PMCID: PMC7588193 DOI: 10.1080/19336950.2020.1835334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Affiliation(s)
- Jingjing Shi
- China Academy of Chinese Medical Sciences, Guanganmen Hospital , Beijing, China
| | - Shuqing Shi
- Graduate School, Beijing University of Chinese Medicine , Beijing, China
| | - Guozhen Yuan
- China Academy of Chinese Medical Sciences, Guanganmen Hospital , Beijing, China
| | - QiuLei Jia
- Graduate School, Beijing University of Chinese Medicine , Beijing, China
| | - Shuai Shi
- China Academy of Chinese Medical Sciences, Guanganmen Hospital , Beijing, China
| | - Xueping Zhu
- China Academy of Chinese Medical Sciences, Guanganmen Hospital , Beijing, China
| | - Yan Zhou
- Graduate School, Beijing University of Chinese Medicine , Beijing, China
| | - Ting Chen
- Graduate School, Beijing University of Chinese Medicine , Beijing, China
| | - Yuanhui Hu
- China Academy of Chinese Medical Sciences, Guanganmen Hospital , Beijing, China
| |
Collapse
|
38
|
Schnipper J, Dhennin-Duthille I, Ahidouch A, Ouadid-Ahidouch H. Ion Channel Signature in Healthy Pancreas and Pancreatic Ductal Adenocarcinoma. Front Pharmacol 2020; 11:568993. [PMID: 33178018 PMCID: PMC7596276 DOI: 10.3389/fphar.2020.568993] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 09/16/2020] [Indexed: 12/11/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer-related deaths in United States and Europe. It is predicted that PDAC will become the second leading cause of cancer-related deaths during the next decades. The development of PDAC is not well understood, however, studies have shown that dysregulated exocrine pancreatic fluid secretion can contribute to pathologies of exocrine pancreas, including PDAC. The major roles of healthy exocrine pancreatic tissue are secretion of enzymes and bicarbonate rich fluid, where ion channels participate to fine-tune these biological processes. It is well known that ion channels located in the plasma membrane regulate multiple cellular functions and are involved in the communication between extracellular events and intracellular signaling pathways and can function as signal transducers themselves. Hereby, they contribute to maintain resting membrane potential, electrical signaling in excitable cells, and ion homeostasis. Despite their contribution to basic cellular processes, ion channels are also involved in the malignant transformation from a normal to a malignant phenotype. Aberrant expression and activity of ion channels have an impact on essentially all hallmarks of cancer defined as; uncontrolled proliferation, evasion of apoptosis, sustained angiogenesis and promotion of invasion and migration. Research indicates that certain ion channels are involved in the aberrant tumor growth and metastatic processes of PDAC. The purpose of this review is to summarize the important expression, localization, and function of ion channels in normal exocrine pancreatic tissue and how they are involved in PDAC progression and development. As ion channels are suggested to be potential targets of treatment they are furthermore suggested to be biomarkers of different cancers. Therefore, we describe the importance of ion channels in PDAC as markers of diagnosis and clinical factors.
Collapse
Affiliation(s)
- Julie Schnipper
- Laboratory of Cellular and Molecular Physiology, UR-4667, University of Picardie Jules Verne, Amiens, France
| | - Isabelle Dhennin-Duthille
- Laboratory of Cellular and Molecular Physiology, UR-4667, University of Picardie Jules Verne, Amiens, France
| | - Ahmed Ahidouch
- Laboratory of Cellular and Molecular Physiology, UR-4667, University of Picardie Jules Verne, Amiens, France.,Department of Biology, Faculty of Sciences, Ibn Zohr University, Agadir, Morocco
| | - Halima Ouadid-Ahidouch
- Laboratory of Cellular and Molecular Physiology, UR-4667, University of Picardie Jules Verne, Amiens, France
| |
Collapse
|
39
|
Thornell IM, Rehman T, Pezzulo AA, Welsh MJ. Paracellular bicarbonate flux across human cystic fibrosis airway epithelia tempers changes in airway surface liquid pH. J Physiol 2020; 598:4307-4320. [PMID: 32627187 PMCID: PMC7589346 DOI: 10.1113/jp280120] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/22/2020] [Indexed: 12/20/2022] Open
Abstract
KEY POINTS Cl- and HCO3- had similar paracellular permeabilities in human airway epithelia. PCl /PNa of airway epithelia was unaltered by pH 7.4 vs. pH 6.0 solutions. Under basal conditions, calculated paracellular HCO3- flux was secretory. Cytokines that increased airway surface liquid pH decreased or reversed paracellular HCO3- flux. HCO3- flux through the paracellular pathway may counterbalance effects of cellular H+ and HCO3- secretion. ABSTRACT Airway epithelia control the pH of airway surface liquid (ASL), thereby optimizing respiratory defences. Active H+ and HCO3- secretion by airway epithelial cells produce an ASL that is acidic compared with the interstitial space. The paracellular pathway could provide a route for passive HCO3- flux that also modifies ASL pH. However, there is limited information about paracellular HCO3- flux, and it remains uncertain whether an acidic pH produced by loss of cystic fibrosis transmembrane conductance regulator anion channels or proinflammatory cytokines might alter the paracellular pathway function. To investigate paracellular HCO3- transport, we studied differentiated primary cultures of human cystic fibrosis (CF) and non-CF airway epithelia. The paracellular pathway was pH-insensitive at pH 6.0 vs. pH 7.4 and was equally permeable to Cl- and HCO3- . Under basal conditions at pH ∼6.6, calculated paracellular HCO3- flux was weakly secretory. Treating epithelia with IL-17 plus TNFα alkalinized ASL pH to ∼7.0, increased paracellular HCO3- permeability, and paracellular HCO3- flux was negligible. Applying IL-13 increased ASL pH to ∼7.4 without altering paracellular HCO3- permeability, and calculated paracellular HCO3- flux was absorptive. These results suggest that HCO3- flux through the paracellular pathway counterbalances, in part, changes in the ASL pH produced via cellular mechanisms. As the pH of ASL increases towards that of basolateral liquid, paracellular HCO3- flux becomes absorptive, tempering the alkaline pH generated by transcellular HCO3- secretion.
Collapse
Affiliation(s)
- Ian M. Thornell
- Department of Internal MedicinePappajohn Biomedical InstituteRoy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityIAUSA
| | - Tayyab Rehman
- Department of Internal MedicinePappajohn Biomedical InstituteRoy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityIAUSA
| | - Alejandro A. Pezzulo
- Department of Internal MedicinePappajohn Biomedical InstituteRoy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityIAUSA
| | - Michael J. Welsh
- Department of Internal MedicinePappajohn Biomedical InstituteRoy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityIAUSA
- Department of Molecular Physiology and BiophysicsPappajohn Biomedical InstituteRoy J. and Lucille A. Carver College of MedicineUniversity of IowaIowa CityIAUSA
- Howard Hughes Medical InstituteUniversity of IowaIowa CityIAUSA
| |
Collapse
|
40
|
Vega G, Guequén A, Philp AR, Gianotti A, Arzola L, Villalón M, Zegarra-Moran O, Galietta LJ, Mall MA, Flores CA. Lack of Kcnn4 improves mucociliary clearance in muco-obstructive lung disease. JCI Insight 2020; 5:140076. [PMID: 32814712 PMCID: PMC7455130 DOI: 10.1172/jci.insight.140076] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022] Open
Abstract
Airway mucociliary clearance (MCC) is the main mechanism of lung defense keeping airways free of infection and mucus obstruction. Airway surface liquid volume, ciliary beating, and mucus are central for proper MCC and critically regulated by sodium absorption and anion secretion. Impaired MCC is a key feature of muco-obstructive diseases. The calcium-activated potassium channel KCa.3.1, encoded by Kcnn4, participates in ion secretion, and studies showed that its activation increases Na+ absorption in airway epithelia, suggesting that KCa3.1-induced hyperpolarization was sufficient to drive Na+ absorption. However, its role in airway epithelium is not fully understood. We aimed to elucidate the role of KCa3.1 in MCC using a genetically engineered mouse. KCa3.1 inhibition reduced Na+ absorption in mouse and human airway epithelium. Furthermore, the genetic deletion of Kcnn4 enhanced cilia beating frequency and MCC ex vivo and in vivo. Kcnn4 silencing in the Scnn1b-transgenic mouse (Scnn1btg/+), a model of muco-obstructive lung disease triggered by increased epithelial Na+ absorption, improved MCC, reduced Na+ absorption, and did not change the amount of mucus but did reduce mucus adhesion, neutrophil infiltration, and emphysema. Our data support that KCa3.1 inhibition attenuated muco-obstructive disease in the Scnn1btg/+ mice. K+ channel modulation may be a therapeutic strategy to treat muco-obstructive lung diseases. Silencing the calcium-activated potassium channel KCa.3.1 improves mucociliary clearance in muco-obstructive lung disease by decreasing sodium absorption in the airways.
Collapse
Affiliation(s)
| | - Anita Guequén
- Centro de Estudios Científicos, Valdivia, Chile.,Universidad Austral de Chile, Valdivia, Chile
| | - Amber R Philp
- Centro de Estudios Científicos, Valdivia, Chile.,Universidad Austral de Chile, Valdivia, Chile
| | | | - Llilian Arzola
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Manuel Villalón
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | - Luis Jv Galietta
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy.,Department of Translational Medical Sciences, University of Naples Federico II, Naples, Italy
| | - Marcus A Mall
- Department of Pediatric Pulmonology, Immunology and Critical Care Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany.,German Center for Lung Research, Berlin, Germany
| | | |
Collapse
|
41
|
Park JH, Ousingsawat J, Cabrita I, Bettels RE, Große-Onnebrink J, Schmalstieg C, Biskup S, Reunert J, Rust S, Schreiber R, Kunzelmann K, Marquardt T. TMEM16A deficiency: a potentially fatal neonatal disease resulting from impaired chloride currents. J Med Genet 2020; 58:247-253. [PMID: 32487539 DOI: 10.1136/jmedgenet-2020-106978] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/14/2020] [Accepted: 04/18/2020] [Indexed: 12/13/2022]
Abstract
INTRODUCTION TMEM16A is a calcium-activated chloride channel expressed in various secretory epithelia. Two siblings presented in early infancy with reduced intestinal peristalsis and recurrent episodes of haemorrhagic diarrhoea. In one of them, the episodes were characterised by hepatic pneumatosis with gas bubbles in the portal vein similar to necrotising enterocolitis of the newborn. METHODS Exome sequencing identified a homozygous truncating pathogenic variant in ANO1. Expression analysis was performed using reverse transcription PCR, western blot and immunohistochemistry. Electrophysiological and cell biological studies were employed to characterise the effects on ion transport both in patient respiratory epithelial cells and in transfected HEK293 cells. RESULTS The identified variant led to TMEM16A dysfunction, which resulted in abolished calcium-activated Cl- currents. Secondarily, CFTR function is affected due to the close interplay between both channels without inducing cystic fibrosis (CF). CONCLUSION TMEM16A deficiency is a potentially fatal disorder caused by abolished calcium-activated Cl- currents in secretory epithelia. Secondary impairment of CFTR function did not cause a CF phenotyp, which may have implications for CF treatment.
Collapse
Affiliation(s)
- Julien H Park
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | | | - Inês Cabrita
- Department of Physiology, University of Regensburg, Regensburg, Bayern, Germany
| | - Ruth E Bettels
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | - Jörg Große-Onnebrink
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | - Christian Schmalstieg
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | | | - Janine Reunert
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | - Stephan Rust
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| | - Rainer Schreiber
- Department of Physiology, University of Regensburg, Regensburg, Bayern, Germany
| | - Karl Kunzelmann
- Department of Physiology, University of Regensburg, Regensburg, Bayern, Germany
| | - Thorsten Marquardt
- Department of Paediatrics, University Hospital Münster, Münster, Nordrhein-Westfalen, Germany
| |
Collapse
|
42
|
Centeio R, Cabrita I, Benedetto R, Talbi K, Ousingsawat J, Schreiber R, Sullivan JK, Kunzelmann K. Pharmacological Inhibition and Activation of the Ca 2+ Activated Cl - Channel TMEM16A. Int J Mol Sci 2020; 21:ijms21072557. [PMID: 32272686 PMCID: PMC7177308 DOI: 10.3390/ijms21072557] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 03/26/2020] [Accepted: 04/02/2020] [Indexed: 12/14/2022] Open
Abstract
TMEM16A is a Ca2+ activated Cl− channel with important functions in airways, intestine, and other epithelial organs. Activation of TMEM16A is proposed as a therapy in cystic fibrosis (CF) to reinstall airway Cl− secretion and to enhance airway surface liquid (ASL). This CFTR-agnostic approach is thought to improve mucociliary clearance and lung function in CF. This could indeed improve ASL, however, mucus release and airway contraction may also be induced by activators of TMEM16A, particularly in inflamed airways of patients with asthma, COPD, or CF. Currently, both activators and inhibitors of TMEM16A are developed and examined in different types of tissues. Here we compare activation and inhibition of endogenous and overexpressed TMEM16A and analyze potential off-target effects. The three well-known blockers benzbromarone, niclosamide, and Ani9 inhibited both TMEM16A and ATP-induced Ca2+ increase by variable degrees, depending on the cell type. Niclosamide, while blocking Ca2+ activated TMEM16A, also induced a subtle but significant Ca2+ store release and inhibited store-operated Ca2+ influx. Niclosamide, benzbromarone and Ani9 also affected TMEM16F whole cell currents, indicating limited specificity for these inhibitors. The compounds Eact, cinnamaldehyde, and melittin, as well as the phosphatidylinositol diC8-PIP2 are the reported activators of TMEM16A. However, the compounds were unable to activate endogenous TMEM16A in HT29 colonic epithelial cells. In contrast, TMEM16A overexpressed in HEK293 cells was potently stimulated by these activators. We speculate that overexpressed TMEM16A might have a better accessibility to intracellular Ca2+, which causes spontaneous activity even at basal intracellular Ca2+ concentrations. Small molecules may therefore potentiate pre-stimulated TMEM16A currents, but may otherwise fail to activate silent endogenous TMEM16A.
Collapse
Affiliation(s)
- Raquel Centeio
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Inês Cabrita
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Roberta Benedetto
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Khaoula Talbi
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Jiraporn Ousingsawat
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | - Rainer Schreiber
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
| | | | - Karl Kunzelmann
- Physiological Institute, University of Regensburg, D-93053 Regensburg, Germany; (R.C.); (I.C.); (R.B.); (K.T.); (J.O.); (R.S.)
- * Correspondence: ; Tel.: +49-(0)941-943-4302; Fax: +49-(0)941-943-4315
| |
Collapse
|
43
|
TMEM16A: An Alternative Approach to Restoring Airway Anion Secretion in Cystic Fibrosis? Int J Mol Sci 2020; 21:ijms21072386. [PMID: 32235608 PMCID: PMC7177896 DOI: 10.3390/ijms21072386] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 03/26/2020] [Accepted: 03/27/2020] [Indexed: 12/18/2022] Open
Abstract
The concept that increasing airway hydration leads to improvements in mucus clearance and lung function in cystic fibrosis has been clinically validated with osmotic agents such as hypertonic saline and more convincingly with cystic fibrosis transmembrane conductance regulator (CFTR) repair therapies. Although rapidly becoming the standard of care in cystic fibrosis (CF), current CFTR modulators do not treat all patients nor do they restore the rate of decline in lung function to normal levels. As such, novel approaches are still required to ensure all with CF have effective therapies. Although CFTR plays a fundamental role in the regulation of fluid secretion across the airway mucosa, there are other ion channels and transporters that represent viable targets for future therapeutics. In this review article we will summarise the current progress with CFTR-independent approaches to restoring mucosal hydration, including epithelial sodium channel (ENaC) blockade and modulators of SLC26A9. A particular emphasis is given to modulation of the airway epithelial calcium-activated chloride channel (CaCC), TMEM16A, as there is controversy regarding whether it should be positively or negatively modulated. This is discussed in light of a recent report describing for the first time bona fide TMEM16A potentiators and their positive effects upon epithelial fluid secretion and mucus clearance.
Collapse
|
44
|
Wang Q, Bai L, Luo S, Wang T, Yang F, Xia J, Wang H, Ma K, Liu M, Wu S, Wang H, Guo S, Sun X, Xiao Q. TMEM16A Ca 2+-activated Cl - channel inhibition ameliorates acute pancreatitis via the IP 3R/Ca 2+/NFκB/IL-6 signaling pathway. J Adv Res 2020; 23:25-35. [PMID: 32071789 PMCID: PMC7016042 DOI: 10.1016/j.jare.2020.01.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2019] [Revised: 01/14/2020] [Accepted: 01/18/2020] [Indexed: 02/08/2023] Open
Abstract
TMEM16A Ca2+-activated Cl- channels are expressed in pancreatic acinar cells and participate in inflammation-associated diseases. Whether TMEM16A contributes to the pathogenesis of acute pancreatitis (AP) remains unknown. Here, we found that increased TMEM16A expression in the pancreatic tissue was correlated with the interleukin-6 (IL-6) level in the pancreatic tissue and in the serum of a cerulein-induced AP mouse model. IL-6 treatment promoted TMEM16A expression in AR42J pancreatic acinar cells via the IL-6 receptor (IL-6R)/signal transducers and activators of transcription 3 (STAT3) signaling pathway. In addition, TMEM16A was co-immunoprecipitated with the inositol 1,4,5-trisphosphate receptor (IP3R) and was activated by IP3R-mediated Ca2+ release. TMEM16A inhibition reduced the IP3R-mediated Ca2+ release induced by cerulein. Furthermore, TMEM16A overexpression activated nuclear factor-κB (NFκB) and increased IL-6 release by increasing intracellular Ca2+. TMEM16A knockdown by shRNAs reduced the cerulein-induced NFκB activation by Ca2+. TMEM16A inhibitors inhibited NFκB activation by decreasing channel activity and reducing TMEM16A protein levels in AR42J cells, and it ameliorated pancreatic damage in cerulein-induced AP mice. This study identifies a novel mechanism underlying the pathogenesis of AP by which IL-6 promotes TMEM16A expression via IL-6R/STAT3 signaling activation, and TMEM16A overexpression increases IL-6 secretion via IP3R/Ca2+/NFκB signaling activation in pancreatic acinar cells. TMEM16A inhibition may be a new potential strategy for treating AP.
Collapse
Key Words
- AP, acute pancreatitis
- Acute pancreatitis
- BAPTA-AM, 1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid-acetyloxymethyl ester
- CCK, cholesystokinin
- CFBE, cystic fibrosis bronchial epithelial
- CaCCinh-A01, Ca2+-activated Cl− channel inhibitor-A01
- EDTA, ethylenediaminetetraacetic acid
- EGF, epidermal growth factor
- EGFP, green fluorescent protein
- EGFR, epidermal growth factor receptor
- EGTA, ethylene glycol-bis(2-aminoethyl ether)-N,N,N',N'-tetraacetic acid
- ELISA, enzyme-linked immunosorbent assay
- ER, endoplasmic reticulum
- FBS, fetal bovine serum
- HEPES, N-2-hydroxyethil-piperazine-N'-2-ethanesulfonic acid
- IL-6, interleukin 6
- IL-6R, interleukin 6 receptor
- IP3R, inositol 1,4,5-trisphosphate receptor
- Inositol 1,4,5-trisphosphate receptor
- Interleukin-6
- NFκB
- NFκB, nuclear factor-κB
- NMDG, N-methyl-D-glucamine
- NP-40, Nonidet P-40
- PACs, pancreatic acinar cells
- RIPA, radio immunoprecipitation assay
- SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electrophoresis
- STAT3, signal transducers and activators of transcription 3
- T16Ainh-A01, TMEM16A inhibitor-A01
- TMEM16A
- Tris, tris(hydroxymethyl)aminomethane
- WT, wild type
- shRNAs, short hairpin RNAs
Collapse
Affiliation(s)
- Qinghua Wang
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China.,Department of Experimental Center, The Affiliated Hospital of Liaoning University of Traditional Chinese Medicine, Shenyang 110032, China
| | - Lichuan Bai
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Shuya Luo
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Tianyu Wang
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Fan Yang
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Jialin Xia
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Hui Wang
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Ke Ma
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Mei Liu
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Shuwei Wu
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Huijie Wang
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| | - Shibin Guo
- Department of Gastroenterological Endoscopy, the First Affiliated Hospital of Dalian Medical University, Dalian 116011, China
| | - Xiaohong Sun
- Department of Neurology, The Fourth Affiliated Hospital of China Medical University, Shenyang 110032, China
| | - Qinghuan Xiao
- Department of Ion Channel Pharmacology, School of Pharmacy, China Medical University, Shenyang 110122, China
| |
Collapse
|
45
|
Vanoni S, Zeng C, Marella S, Uddin J, Wu D, Arora K, Ptaschinski C, Que J, Noah T, Waggoner L, Barski A, Kartashov A, Rochman M, Wen T, Martin L, Spence J, Collins M, Mukkada V, Putnam P, Naren A, Chehade M, Rothenberg ME, Hogan SP. Identification of anoctamin 1 (ANO1) as a key driver of esophageal epithelial proliferation in eosinophilic esophagitis. J Allergy Clin Immunol 2020; 145:239-254.e2. [PMID: 31647967 PMCID: PMC7366251 DOI: 10.1016/j.jaci.2019.07.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 07/13/2019] [Accepted: 07/29/2019] [Indexed: 12/24/2022]
Abstract
BACKGROUND The pathology of eosinophilic esophagitis (EoE) is characterized by eosinophil-rich inflammation, basal zone hyperplasia (BZH), and dilated intercellular spaces, and the underlying processes that drive the pathologic manifestations of the disease remain largely unexplored. OBJECTIVE We sought to investigate the involvement of the calcium-activated chloride channel anoctamin 1 (ANO1) in esophageal proliferation and the histopathologic features of EoE. METHODS We examined mRNA and protein expression of ANO1 in esophageal biopsy samples from patients with EoE and in mice with EoE. We performed molecular and cellular analyses and ion transport assays on an in vitro esophageal epithelial 3-dimensional model system (EPC2-ALI) and murine models of EoE to define the relationship between expression and function of ANO1 and esophageal epithelial proliferation in patients with EoE. RESULTS We observed increased ANO1 expression in esophageal biopsy samples from patients with EoE and in mice with EoE. ANO1 was expressed within the esophageal basal zone, and expression correlated positively with disease severity (eosinophils/high-power field) and BZH. Using an in vitro esophageal epithelial 3-dimensional model system revealed that ANO1 undergoes chromatin modification and rapid upregulation of expression after IL-13 stimulation, that ANO1 is the primary apical IL-13-induced Cl- transport mechanism within the esophageal epithelium, and that loss of ANO1-dependent Cl- transport abrogated esophageal epithelial proliferation. Mechanistically, ANO1-dependent regulation of basal cell proliferation was associated with modulation of TP63 expression and phosphorylated cyclin-dependent kinase 2 levels. CONCLUSIONS These data identify a functional role for ANO1 in esophageal cell proliferation and BZH in patients with EoE and provide a rationale for pharmacologic intervention of ANO1 function in patients with EoE.
Collapse
Affiliation(s)
- Simone Vanoni
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; PharmGenetix Gmbh, Niederalm-Anif, Austria
| | - Chang Zeng
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Sahiti Marella
- Mary H Weiser Food Allergy Center and Department of Pathology, Ann Arbor, Mich
| | - Jazib Uddin
- Mary H Weiser Food Allergy Center and Department of Pathology, Ann Arbor, Mich
| | - David Wu
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Kavisha Arora
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | | | - Jianwen Que
- Department of Medicine, Columbia University Medical Center, New York, NY
| | - Taeko Noah
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Mary H Weiser Food Allergy Center and Department of Pathology, Ann Arbor, Mich
| | - Lisa Waggoner
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Artem Barski
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Andrey Kartashov
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Mark Rochman
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Ting Wen
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Lisa Martin
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Jason Spence
- Departments of Biomedical Engineering, Internal Medicine and Cell and Developmental Biology, University of Michigan, Ann Arbor, Mich
| | - Margaret Collins
- Division of Pathology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Vincent Mukkada
- Division of Gastroenterology, Nutrition and Hepatology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Phillip Putnam
- Division of Gastroenterology, Nutrition and Hepatology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Anjaparavanda Naren
- Division of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Mirna Chehade
- Mount Sinai Center for Eosinophilic Disorders, Jaffe Food Allergy Institute, Icahn School of Medicine at Mount Sinai, New York, NY
| | - Marc E Rothenberg
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Simon P Hogan
- Division of Allergy and Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Mary H Weiser Food Allergy Center and Department of Pathology, Ann Arbor, Mich.
| |
Collapse
|
46
|
Simões FB, Quaresma MC, Clarke LA, Silva IA, Pankonien I, Railean V, Kmit A, Amaral MD. TMEM16A chloride channel does not drive mucus production. Life Sci Alliance 2019; 2:2/6/e201900462. [PMID: 31732694 PMCID: PMC6859295 DOI: 10.26508/lsa.201900462] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 10/29/2019] [Accepted: 11/06/2019] [Indexed: 01/07/2023] Open
Abstract
Despite being essential for airway hydration, TMEM16A is not required for mucus (MUC5AC) production. Cell proliferation is the main driver for TMEM16A up-regulation during inflammation. Airway mucus obstruction is the main cause of morbidity in cystic fibrosis, a disease caused by mutations in the CFTR Cl− channel. Activation of non-CFTR Cl− channels such as TMEM16A can likely compensate for defective CFTR. However, TMEM16A was recently described as a key driver in mucus production/secretion. Here, we have examined whether indeed there is a causal relationship between TMEM16A and MUC5AC production, the main component of respiratory mucus. Our data show that TMEM16A and MUC5AC are inversely correlated during differentiation of human airway cells. Furthermore, we show for the first time that the IL-4–induced TMEM16A up-regulation is proliferation-dependent, which is supported by the correlation found between TMEM16A and Ki-67 proliferation marker during wound healing. Consistently, the notch signaling activator DLL4 increases MUC5AC levels without inducing changes neither in TMEM16A nor in Ki-67 expression. Moreover, TMEM16A inhibition decreased airway surface liquid height. Altogether, our findings demonstrate that up-regulation of TMEM16A and MUC5AC is only circumstantial under cell proliferation, but with no causal relationship between them. Thus, although essential for airway hydration, TMEM16A is not required for MUC5AC production.
Collapse
Affiliation(s)
- Filipa B Simões
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Margarida C Quaresma
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Luka A Clarke
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Iris Al Silva
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Ines Pankonien
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Violeta Railean
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Arthur Kmit
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| | - Margarida D Amaral
- University of Lisboa, Faculty of Sciences, BioISI-Biosystems & Integrative Sciences Institute, Lisboa, Portugal
| |
Collapse
|
47
|
Yu B, Zhu X, Yang X, Jin L, Xu J, Ma T, Yang H. Plumbagin Prevents Secretory Diarrhea by Inhibiting CaCC and CFTR Channel Activities. Front Pharmacol 2019; 10:1181. [PMID: 31649543 PMCID: PMC6795057 DOI: 10.3389/fphar.2019.01181] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 09/13/2019] [Indexed: 12/12/2022] Open
Abstract
Secretory diarrhea, which primarily originates through intestinal pathogens and viruses, is a health burden in many regions worldwide. Enterocyte Cl− channels, as the final step in enterotoxin-induced fluid secretion, constitute an attractive class of targets for diarrhea therapy. Chloride channel inhibitors have become a new class of candidates for antisecretion and anti-intestinal motility agents. In the present study, we identified plumbagin as a transmembrane protein 16A (TMEM16A) inhibitor in a cell-based fluorescence-quenching assay, and the IC50 value was ∼12.46 µM. Short-circuit current measurements showed that plumbagin reversibly inhibited the Eact-induced Cl− current on the apical side of TMEM16A-transfected Fischer rat thyroid (FRT) cells with no significant effect on cytoplasmic Ca2+ signaling. Notably, plumbagin also inhibited the activity of intestinal epithelial calcium-activated chloride channel (CaCC) and cystic fibrosis transmembrane conductance regulator (CFTR) in both HT-29 cells and mouse colons, but had no effects on the activity of the Na+-K+ ATPase or K+ channels. In in vivo experiments, the administration of plumbagin reduced both Escherichia coli heat-stable enterotoxin (STa)- and cholera toxin (CT)-induced intestinal fluid secretion. In neonatal mouse models of CT- and rotavirus infection-induced diarrhea, 0.4 µg plumbagin inhibited secretory diarrhea by >40% and 50%, respectively, without affecting intestinal epithelial integrity or the rotaviral infection. In addition, plumbagin exerted inhibitory effects on the vasoactive intestinal peptide (VIP)-, prostaglandin E2 (PGE2)-, and 5-hydroxytryptamine (5-HT)-stimulated Cl− currents. In the evaluations of intestinal motility, plumbagin significantly delayed intestinal motility and inhibited intestinal smooth muscle contractility without an evident impact on contractive frequency. Collectively, our results indicate that plumbagin inhibits both Ca2+- and cAMP-activated Cl− channels, accounting for the mechanisms of plumbagin inhibition of chloride secretion and intestinal motility. Thus, plumbagin can be a lead compound in the treatment of CT-induced, Traveler’s, and rotaviral diarrhea, as well as other types of secretory diarrhea that result from excessive intestinal fluid secretion and increased intestinal peristalsis.
Collapse
Affiliation(s)
- Bo Yu
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| | - Xiaojuan Zhu
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| | - Xinyu Yang
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| | - Lingling Jin
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Jia Xu
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| | - Tonghui Ma
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| | - Hong Yang
- School of Life Sciences, Liaoning Provincial Key Laboratory of Biotechnology and Drug Discovery, Liaoning Normal University, Dalian, China
| |
Collapse
|
48
|
Kunzelmann K, Centeio R, Wanitchakool P, Cabrita I, Benedetto R, Saha T, Hoque KM, Schreiber R. Control of Ion Transport by Tmem16a Expressed in Murine Intestine. Front Physiol 2019; 10:1262. [PMID: 31680994 PMCID: PMC6797858 DOI: 10.3389/fphys.2019.01262] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/17/2019] [Indexed: 12/30/2022] Open
Abstract
Cl– secretion by the human and murine intestinal epithelium occurs through the cystic fibrosis transmembrane conductance regulator (cftr). However, the Ca2+ activated Cl– channel Tmem16a was shown to contribute to Cl– secretion, mainly, but not exclusively, as a basolaterally located Cl– channel that controls basolateral Ca2+ signaling, and thus activation of basolateral Ca2+ dependent Sk4 K+ channels. In intestinal goblet cells, Tmem16a was shown to regulated Ca2+ signals required for exocytosis of mucus. Because a recent report denied the existence and functional role of Tmem16a in murine intestine, we reexamined in detail expression of mRNA and protein for Tmem16a in mouse colon. In experiments using short-circuited Ussing chamber and whole cell patch-clamp techniques, we further compared ion transport in wild type (WT) colon with that in mice with intestinal epithelial specific knockout of Tmem16a. As reported earlier we fully confirm expression of Tmem16a in colonic epithelial cells and the role of Tmem16a for both Ca2+-dependent and cAMP-regulated ion secretion.
Collapse
Affiliation(s)
- Karl Kunzelmann
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| | - Raquel Centeio
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| | | | - Inês Cabrita
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| | - Roberta Benedetto
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| | - Tultul Saha
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Kazi Mirajul Hoque
- Division of Pathophysiology, National Institute of Cholera and Enteric Diseases, Kolkata, India.,Department of Physiology, University of Maryland School of Medicine, Baltimore, MD, United States
| | - Rainer Schreiber
- Institut für Physiologie, Universität Regensburg, Regensburg, Germany
| |
Collapse
|
49
|
Kuan SP, Liao YSJ, Davis KM, Messer JG, Zubcevic J, Aguirre JI, Reznikov LR. Attenuated Amiloride-Sensitive Current and Augmented Calcium-Activated Chloride Current in Marsh Rice Rat (Oryzomys palustris) Airways. iScience 2019; 19:737-748. [PMID: 31491720 PMCID: PMC6731178 DOI: 10.1016/j.isci.2019.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 07/22/2019] [Accepted: 08/05/2019] [Indexed: 11/29/2022] Open
Abstract
Prolonged heat and sea salt aerosols pose a challenge for the mammalian airway, placing the protective airway surface liquid (ASL) at risk for desiccation. Thus, mammals inhabiting salt marshes might have acquired adaptations for ASL regulation. We studied the airways of the rice rat, a rodent that inhabits salt marshes. We discovered negligible Na+ transport through the epithelial sodium channel (ENaC). In contrast, carbachol induced a large Cl- secretory current that was blocked by the calcium-activated chloride channel (CaCC) inhibitor CaCCinhi-A01. Decreased mRNA expression of α, β, and γ ENaC, and increased mRNA expression of the CaCC transmembrane member 16A, distinguished the rice rat airway. Rice rat airway cultures also secreted fluid in response to carbachol and displayed an exaggerated expansion of the ASL volume when challenged with 3.5% NaCl. These data suggest that the rice rat airway might possess unique ion transport adaptations to facilitate survival in the salt marsh environment.
Collapse
Affiliation(s)
- Shin-Ping Kuan
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Yan-Shin J Liao
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Katelyn M Davis
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Jonathan G Messer
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Jasenka Zubcevic
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - J Ignacio Aguirre
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA
| | - Leah R Reznikov
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32610, USA.
| |
Collapse
|
50
|
Lee B, Hong GS, Lee SH, Kim H, Kim A, Hwang EM, Kim J, Lee MG, Yang JY, Kweon MN, Tse CM, Mark D, Oh U. Anoctamin 1/TMEM16A controls intestinal Cl - secretion induced by carbachol and cholera toxin. Exp Mol Med 2019; 51:1-14. [PMID: 31383845 PMCID: PMC6802608 DOI: 10.1038/s12276-019-0287-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Revised: 03/07/2019] [Accepted: 03/11/2019] [Indexed: 12/17/2022] Open
Abstract
Calcium-activated chloride channels (CaCCs) mediate numerous physiological functions and are best known for the transport of electrolytes and water in epithelia. In the intestine, CaCC currents are considered necessary for the secretion of fluid to protect the intestinal epithelium. Although genetic ablation of ANO1/TMEM16A, a gene encoding a CaCC, reduces the carbachol-induced secretion of intestinal fluid, its mechanism of action is still unknown. Here, we confirm that ANO1 is essential for the secretion of intestinal fluid. Carbachol-induced transepithelial currents were reduced in the proximal colon of Ano1-deficient mice. Surprisingly, cholera toxin-induced and cAMP-induced fluid secretion, believed to be mediated by CFTR, were also significantly reduced in the intestine of Ano1-deficient mice. ANO1 is largely expressed in the apical membranes of intestines, as predicted for CaCCs. The Ano1-deficient colons became edematous under basal conditions and had a greater susceptibility to dextran sodium sulfate-induced colitis. However, Ano1 depletion failed to affect tumor development in a model of colorectal cancer. We thus conclude that ANO1 is necessary for cAMP- and carbachol-induced Cl− secretion in the intestine, which is essential for the protection of the intestinal epithelium from colitis. An ion channel, a membrane protein allowing ion transport, that controls the flow of chloride is needed for proper secretion of protective fluids in the intestine. Uhtaek Oh from the Korea Institute of Science & Technology in Seoul, South Korea, and colleagues showed that cells lining the intestinal surface express a calcium-activated chloride channel called anoctamin-1 (ANO1) that regulates fluid secretion in the gut. Compared to control animals, ANO1-deficient mice released less fluid into their intestines following exposure to a diarrhea-inducing toxin or to a chloride transport–stimulating signaling molecule. This fluid secretion was previously thought to be mediated via a different ion channel. The ANO1-deficient mice accumulated fluid within colonic tissues, which increased their susceptibility to colitis. The findings point to ANO1 activation as a potential therapeutic strategy for treating colitis.
Collapse
Affiliation(s)
- Byeongjun Lee
- College of Pharmacy, Seoul National University, Seoul, 08826, Korea
| | - Gyu-Sang Hong
- Brain Science Institute, Korea Institute of Science & Technology (KIST), Seoul, 02792, Korea
| | - Sung Hoon Lee
- College of Pharmacy, Chung-Ang University, Seoul, 06974, Korea
| | - Hyungsup Kim
- Brain Science Institute, Korea Institute of Science & Technology (KIST), Seoul, 02792, Korea
| | - Ajung Kim
- Brain Science Institute, Korea Institute of Science & Technology (KIST), Seoul, 02792, Korea
| | - Eun Mi Hwang
- Brain Science Institute, Korea Institute of Science & Technology (KIST), Seoul, 02792, Korea
| | - Jiyoon Kim
- Department of Pharmacology, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Min Goo Lee
- Department of Pharmacology, Yonsei University College of Medicine, Seoul, 03722, Korea
| | - Jin-Young Yang
- Mucosal Immunology Laboratory, Department of Convergence Medicine, University of Ulsan College of Medicine/Asan Medical Center, Seoul, 05505, Korea
| | - Mi-Na Kweon
- Mucosal Immunology Laboratory, Department of Convergence Medicine, University of Ulsan College of Medicine/Asan Medical Center, Seoul, 05505, Korea
| | - Chung-Ming Tse
- Departments of Physiology and Medicine, Division of Gastroenterois maintained by the opening of plasmalogy, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Donowitz Mark
- Departments of Physiology and Medicine, Division of Gastroenterois maintained by the opening of plasmalogy, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Uhtaek Oh
- College of Pharmacy, Seoul National University, Seoul, 08826, Korea. .,Brain Science Institute, Korea Institute of Science & Technology (KIST), Seoul, 02792, Korea.
| |
Collapse
|