1
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Xiao HL, Xiao YJ, Wang Q, Chen ML, Jiang AL. Moxibustion Regulates Gastrointestinal Motility via HCN1 in Functional Dyspepsia Rats. Med Sci Monit 2021; 27:e932885. [PMID: 34845181 PMCID: PMC8642983 DOI: 10.12659/msm.932885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Background Moxibustion therapy has been found to ameliorate clinical symptoms of functional dyspepsia (FD). We aimed to examine the regulatory effect of moxibustion on the gastrointestinal (GI) motility in FD and explore the underlying mechanism based on the hyperpolarization-activated cyclic nucleotide-gated cation channel 1 (HCN1). Material/Methods Moxibustion therapy was used in FD rats induced by using classic tail-pinch and irregular feeding. Weight gain and food intake were recorded weekly, followed by detecting gastric residual rate (GRR) and small intestine propulsion rate (IPR). Next, western blotting was performed to determine the expression levels of HCN1 in the gastric antrum. qRT-PCR was used to detect HCN1 in the small intestine and hypothalamic satiety center. Double immunolabeling was used for HCN1 and ICCs in gastric antrum and small intestine. Results The obtained results suggested that moxibustion treatment could increase weight gain and food intake in FD rats. The GRR and IPR were compared among the groups, which showed that moxibustion treatment could decrease GRR and increase IPR. Moxibustion increased the expression of HCN1 in the gastric antrum, small intestine, and hypothalamic satiety center. Histologically, the co-expressions of HCN1 and ICCs tended to increase in gastric antrum and small intestine. Meanwhile, HCN channel inhibitor ZD7288 prevented the above-mentioned therapeutic effects of moxibustion. Conclusions The results of the present study suggest that moxibustion can effectively improve the GI motility of FD rats, which may be related to the upregulation of HCN1 expression in gastric antrum, small intestine, and satiety center.
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Affiliation(s)
- Hong-Ling Xiao
- School of Nursing, Second Military Medical University, Shanghai, China (mainland).,School of Nursing, Tianjin University of Chinese Medicine, Tianjin, China (mainland)
| | - Yun-Jiu Xiao
- School of Nursing, Anhui University of Chinese Medicine, Hefei, Anhui, China (mainland)
| | - Qian Wang
- School of Nursing, Anhui University of Chinese Medicine, Hefei, Anhui, China (mainland)
| | - Mei-Ling Chen
- School of Nursing, Anhui University of Chinese Medicine, Hefei, Anhui, China (mainland)
| | - An-Li Jiang
- School of Nursing, Second Military Medical University, Shanghai, China (mainland)
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2
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Choi S, Seo H, Lee K, Shin DH, Wu MJ, Wu W, Huang X, Zhang J, Hong C, Jun JY. Hyperpolarization-activated cyclic nucleotide-gated channels working as pacemaker channels in colonic interstitial cells of Cajal. J Cell Mol Med 2021; 26:364-374. [PMID: 34845842 PMCID: PMC8743669 DOI: 10.1111/jcmm.17087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 10/28/2021] [Accepted: 11/17/2021] [Indexed: 11/29/2022] Open
Abstract
Hyperpolarization‐activated cyclic nucleotide‐gated (HCN) channels function as pacemaker channels in spontaneously active cells. We studied the existence of HCN channels and their functional roles in the interstitial cells of Cajal (ICC) from the mouse colon using electrophysiological, immunohistochemical and molecular techniques. HCN1 and HCN3 channels were detected in anoctamin‐1 (Ca2+‐activated Cl− channel; ANO1)‐positive cells within the muscular and myenteric layers in colonic tissues. The mRNA transcripts of HCN1 and HCN3 channels were expressed in ANO1‐positive ICC. In the deletion of HCN1 and HCN3 channels in colonic ICC, the pacemaking potential frequency was reduced. Basal cellular adenylate cyclase activity was decreased by adenylate cyclase inhibitor in colonic ICC, whereas cAMP‐specific phosphodiesterase inhibitors increased it. 8‐Bromo‐cyclic AMP and rolipram increased spontaneous intracellular Ca2+ oscillations. In addition, Ca2+‐dependent adenylate cyclase 1 (AC1) mRNA was detected in colonic ICC. Sulprostone, a PGE2‐EP3 agonist, increased the pacemaking potential frequency, maximum rate of rise of resting membrane in pacemaker potentials and basal cellular adenylate cyclase activity in colonic ICC. These results indicate that HCN channels exist in colonic ICC and participate in generating pacemaking potentials. Thus, HCN channels may be therapeutic targets in disturbed colonic motility disorders.
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Affiliation(s)
- Seok Choi
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Hyunhyo Seo
- Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Kyungmin Lee
- Department of Anatomy, Brain Science & Engineering Institute, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Dong Hoon Shin
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Mei Jin Wu
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Wenhao Wu
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Xingyou Huang
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Jingwei Zhang
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Chansik Hong
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
| | - Jae Yeoul Jun
- Department of Physiology, College of Medicine, Chosun University, Gwangju, Korea
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3
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Benzoni P, Bertoli G, Giannetti F, Piantoni C, Milanesi R, Pecchiari M, Barbuti A, Baruscotti M, Bucchi A. The funny current: Even funnier than 40 years ago. Uncanonical expression and roles of HCN/f channels all over the body. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2021; 166:189-204. [PMID: 34400215 DOI: 10.1016/j.pbiomolbio.2021.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 06/25/2021] [Accepted: 08/09/2021] [Indexed: 12/25/2022]
Abstract
Discovered some 40 years ago, the If current has since been known as the "pacemaker" current due to its role in the initiation and modulation of the heartbeat and of neuronal excitability. But this is not all, the funny current keeps entertaining the researchers; indeed, several data discovering novel and uncanonical roles of f/HCN channel are quickly accumulating. In the present review, we provide an overview of the expression and cellular functions of HCN/f channels in a variety of systems/organs, and particularly in sour taste transduction, hormones secretion, activation of astrocytes and microglia, inhibition of osteoclastogenesis, renal ammonium excretion, and peristalsis in the gastrointestinal and urine systems. We also analyzed the role of HCN channels in sustaining cellular respiration in mitochondria and their participation to mitophagy under specific conditions. The relevance of HCN currents in undifferentiated cells, and specifically in the control of stem cell cycle and in bioelectrical signals driving left/right asymmetry during zygote development, is also considered. Finally, we present novel data concerning the expression of HCN mRNA in human leukocytes. We can thus conclude that the emerging evidence presented in this review clearly points to an increasing interest and importance of the "funny" current that goes beyond its role in cardiac sinoatrial and neuronal excitability regulation.
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Affiliation(s)
- Patrizia Benzoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Giorgia Bertoli
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Federica Giannetti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Chiara Piantoni
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy; Present Address: Institute of Neurophysiology, Hannover Medical School, Carl-Neuberg-Str.1, 30625, Hannover, Germany
| | - Raffaella Milanesi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy; Present Address: Dipartimento di Medicina Veterinaria, Università degli Studi di Milano, Via Dell'Università 6, 26900, Lodi, Italy
| | - Matteo Pecchiari
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Via L. Mangiagalli 32, 20133, Milan, Italy
| | - Andrea Barbuti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Mirko Baruscotti
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy
| | - Annalisa Bucchi
- The Cell Physiology MiLab, Department of Biosciences, Università degli Studi di Milano, Via G. Celoria 26, 20133, Milan, Italy.
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4
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Kuwahara Y, Kato I, Inui T, Marunaka Y, Kuwahara A. The effect of Xenin25 on spontaneous circular muscle contractions of rat distal colon in vitro. Physiol Rep 2021; 9:e14752. [PMID: 33600071 PMCID: PMC7891183 DOI: 10.14814/phy2.14752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 09/19/2020] [Accepted: 09/22/2020] [Indexed: 12/13/2022] Open
Abstract
Xenin25 has a variety of physiological functions in the Gastrointestinal (GI) tract, including ion transport and motility. However, the motility responses in the colon induced by Xenin25 remain poorly understood. Therefore, the effect of Xenin25 on the spontaneous circular muscle contractions of the rat distal colon was investigated using organ bath chambers and immunohistochemistry. Xenin25 induced the inhibition followed by postinhibitory spontaneous contractions with a higher frequency in the rat distal colon. This inhibitory effect of Xenin25 was significantly suppressed by TTX but not by atropine. The inhibitory time (the duration of inhibition) caused by Xenin25 was shortened by the NTSR1 antagonist SR48692, the NK1R antagonist CP96345, the VPAC2 receptor antagonist PG99-465, the nitric oxide-sensitive guanylate-cyclase inhibitor ODQ, and the Ca2+ -dependent K+ channel blocker apamin. The higher frequency of postinhibitory spontaneous contractions induced by Xenin25 was also attenuated by ODQ and apamin. SP-, NOS-, and VIP-immunoreactive neurons were detected in the myenteric plexus (MP) of the rat distal colon. Small subsets of the SP-positive neurons were also Calbindin positive. Most of the VIP-positive neurons were also NOS positive, and small subsets of the NK1R-positive neurons were also VIP positive. Based on the present results, we propose the following mechanism. Xenin25 activates neuronal NTSR1 on the SP neurons of IPANs, and transmitters from the VIP and apamin-sensitive NO neurons synergistically inhibit the spontaneous circular muscle contractions via NK1R. Subsequently, the postinhibitory spontaneous contractions are induced by the offset of apamin-sensitive NO neuron activation via the interstitial cells of Cajal. In addition, Xenin25 also activates the muscular NTSR1 to induce relaxation. Thus, Xenin25 is considered to be an important modulator of post prandial circular muscle contraction of distal colon since the release of Xenin25 from enteroendocrine cells is stimulated by food intake.
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Affiliation(s)
- Yuko Kuwahara
- Department of Molecular cell PhysiologyGraduate School of Medical ScienceKyoto Prefectural University of MedicineKyotoJapan
- Research Unit for Epithelial PhysiologyResearch Center for Drug Discovery and Pharmaceutical Development ScienceResearch Organization of Science and TechnologyRitsumeikan UniversityKusatsuJapan
| | - Ikuo Kato
- Department of Medical BiochemistryKobe Pharmaceutical UniversityKobeJapan
| | | | - Yoshinori Marunaka
- Department of Molecular cell PhysiologyGraduate School of Medical ScienceKyoto Prefectural University of MedicineKyotoJapan
- Research Unit for Epithelial PhysiologyResearch Center for Drug Discovery and Pharmaceutical Development ScienceResearch Organization of Science and TechnologyRitsumeikan UniversityKusatsuJapan
- Research Institute for Clinical PhysiologyKyoto Industrial Health AssociationKyotoJapan
| | - Atsukazu Kuwahara
- Research Unit for Epithelial PhysiologyResearch Center for Drug Discovery and Pharmaceutical Development ScienceResearch Organization of Science and TechnologyRitsumeikan UniversityKusatsuJapan
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5
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Santoro B, Shah MM. Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels as Drug Targets for Neurological Disorders. Annu Rev Pharmacol Toxicol 2020; 60:109-131. [PMID: 31914897 DOI: 10.1146/annurev-pharmtox-010919-023356] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are voltage-gated ion channels that critically modulate neuronal activity. Four HCN subunits (HCN1-4) have been cloned, each having a unique expression profile and distinctive effects on neuronal excitability within the brain. Consistent with this, the expression and function of these subunits are altered in diverse ways in neurological disorders. Here, we review current knowledge on the structure and distribution of the individual HCN channel isoforms, their effects on neuronal activity under physiological conditions, and how their expression and function are altered in neurological disorders, particularly epilepsy, neuropathic pain, and affective disorders. We discuss the suitability of HCN channels as therapeutic targets and how drugs might be strategically designed to specifically act on particular isoforms. We conclude that medicines that target individual HCN isoforms and/or their auxiliary subunit, TRIP8b, may provide valuable means of treating distinct neurological conditions.
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Affiliation(s)
- Bina Santoro
- Department of Neuroscience, Columbia University, New York, NY 10027, USA
| | - Mala M Shah
- Department of Pharmacology, School of Pharmacy, University College London, London WC1N 1AX, United Kingdom;
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6
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Fehsenfeld S, Wood CM. A potential role for hyperpolarization-activated cyclic nucleotide-gated sodium/potassium channels (HCNs) in teleost acid-base and ammonia regulation. Comp Biochem Physiol B Biochem Mol Biol 2020; 248-249:110469. [PMID: 32653509 DOI: 10.1016/j.cbpb.2020.110469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/24/2020] [Accepted: 07/02/2020] [Indexed: 11/27/2022]
Abstract
Increasing evidence suggests the involvement of hyperpolarization-activated cyclic nucleotide-gated sodium/potassium channels (HCNs) not only in cardiac and neural function, but also in more general physiological processes including acid-base and ammonia regulation. We have identified four different HCN paralogs/isoforms in the goldfish Carassius auratus (CaHCN1, CaHCN2b, CaHCN4a and CaHCN4b) as likely candidates to contribute to renal, branchial and intestinal acid-base and ammonia regulation in this teleost. Quantitative real-time PCR showed not only high mRNA abundance of all isoforms in heart and brain, but also detectable levels (particularly of CaHCN2b and CaHCN4b) in non-excitable tissues, including gills and kidneys. In response to an internal or external acid-base and/or ammonia disturbance caused by feeding or high environmental ammonia, respectively, we observed differential and tissue-specific changes in mRNA abundance of all isoforms except CaHCN4b. Furthermore, our data suggest that the functions of specific HCN channels are supplemented by certain Rhesus glycoprotein functions to help in the protection of tissues from elevated ammonia levels, or as potential direct routes for ammonia transport in gills, kidney, and gut. The present results indicate important individual roles for each HCN isoform in response to acid-base and ammonia disturbances.
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Affiliation(s)
- Sandra Fehsenfeld
- Université du Quebec à Rimouski, Département de biologie, chimie et géographie, 300 Allée des Ursulines, Rimouski, QC G5L 3A1, Canada; University of British Columbia, Department of Zoology, 4200 - 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada.
| | - Chris M Wood
- University of British Columbia, Department of Zoology, 4200 - 6270 University Blvd., Vancouver, BC V6T 1Z4, Canada
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7
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Al-Naggar IM, Hardy CC, Taweh OG, Grabauskas T, Mulkey DK, Kuchel GA, Smith PP. HCN as a Mediator of Urinary Homeostasis: Age-Associated Changes in Expression and Function in Adrenergic Detrusor Relaxation. J Gerontol A Biol Sci Med Sci 2019; 74:325-329. [PMID: 30124776 DOI: 10.1093/gerona/gly137] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Indexed: 12/19/2022] Open
Abstract
The Hyperpolarization activated, cyclic nucleotide gated (HCN) channel is a candidate mediator of neuroendocrine influence over detrusor tonus during filling. In other tissues, HCN loss with aging is linked to declines in rhythmicity and function. We hypothesized that HCN has an age-sensitive expression profile and functional role in adrenergic bladder relaxation. HCN was examined in bladders from young (2-6 months) and old (18-24 months) C57BL/6 female mice, using qRT-PCR, RNAScope, and Western blots. Isometric tension studies were conducted using bladder strips from young wild-type (YWT), old wild-type (OWT), and young HCN1 knock-out (YKO) female mice to test the role HCN in effects of β-adrenergic stimulation. Hcn1 is the dominant HCN isoform RNA in the mouse bladder wall, and is diminished with age. Location of Hcn RNA within the mouse bladder wall is isoform-specific, with HCN1 limited to the detrusor layer. Passively-tensioned YWT bladder strips are relaxed by isoproterenol in the presence of HCN function, where OWT strips are relaxed only in the presence of HCN blockade. HCN has an age-specific expression and function in adrenergic detrusor relaxation in mouse bladder strips.
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Affiliation(s)
- Iman M Al-Naggar
- UConn Center on Aging, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Cara C Hardy
- UConn Center on Aging, University of Connecticut School of Medicine, Farmington, Connecticut.,Department of Neuroscience, UConn Health, Farmington, Connecticut
| | - Omar G Taweh
- Department of Physiology and Neurobiology, University of Connecticut, Farmington, Connecticut
| | - Titas Grabauskas
- UConn Center on Aging, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Daniel K Mulkey
- Department of Physiology and Neurobiology, University of Connecticut, Farmington, Connecticut.,University of Connecticut Institute for Brain and Cognitive Science, Storrs, Connecticut
| | - George A Kuchel
- UConn Center on Aging, University of Connecticut School of Medicine, Farmington, Connecticut
| | - Phillip P Smith
- UConn Center on Aging, University of Connecticut School of Medicine, Farmington, Connecticut.,Department of Neuroscience, UConn Health, Farmington, Connecticut.,Department of Physiology and Neurobiology, University of Connecticut, Farmington, Connecticut.,Department of Surgery, UConn School of Medicine, Farmington, Connecticut
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8
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Sun B, Dong X, Zhao J, Yang Z, Zhang Y, Li L. Differentiation of human urine-derived stem cells into interstitial cells of Cajal-like cells by exogenous gene modification: A preliminary study. Biochem Biophys Res Commun 2019; 523:10-17. [PMID: 31831171 DOI: 10.1016/j.bbrc.2019.09.121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 09/27/2019] [Indexed: 02/07/2023]
Abstract
Human urine-derived stem cells (hUSCs) show multipotential differentiation ability and can differentiate into mesodermal cell lineages. Interstitial cells of Cajal-like cells (ICC-LCs) are crucial for the pace-making function of spontaneous contraction in the bladder. However, the mechanisms by which hUSCs generate ICC-LCs have not been elucidated. In this study, we developed a strategy for directional differentiation of hUSCs into ICC-LCs. hUSCs were transfected with lentiviral vectors encoding c-Kit, stem cell factor (SCF), hyperpolarization activated cyclic nucleotide gated potassium channel 4 (HCN4), and 5-azacytidine induced 2 (AZI2) genes, and the cells were cultured for an additional 7 days in specific medium. The expression of the surface marker c-Kit on ICC-LCs was determined at 7 days after transfection. hUSCs were successfully expanded and transfected with the four lentiviral vectors. hUSCs transfected with lentiviral-c-Kit, lentiviral-HCN4, and lentiviral-AZI2 showed higher expression of c-Kit 7 days after transfection, but only the lentiviral-HCN4-transfected cells showed morphological alterations in ICC-LCs. These cells also displayed visible HCN current amplitude and density. This approach may provide a new strategy for the treatment of underactive bladder.
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Affiliation(s)
- Bishao Sun
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Xingyou Dong
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Jiang Zhao
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Zhenxing Yang
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China
| | - Yuanyuan Zhang
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC, 27157, USA
| | - Longkun Li
- Department of Urology, Second Affiliated Hospital, Army Medical University, Chongqing, 400037, China.
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9
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Kim JN, Kim BJ. Depolarization of pacemaker potentials by caffeic acid phenethyl ester in interstitial cells of Cajal from the murine small intestine. Can J Physiol Pharmacol 2019; 98:201-210. [PMID: 31689119 DOI: 10.1139/cjpp-2019-0452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Interstitial cells of Cajal (ICCs) are pacemaker cells in the gastrointestinal (GI) tract and generate pacemaker potentials. In this study, we investigated the effects of caffeic acid phenethyl ester (CAPE) on the pacemaker potentials of ICCs from the mouse small or large intestine. Using the whole-cell patch-clamp configuration, we found that CAPE depolarized the pacemaker potentials of cultured ICCs from the murine small intestine in a dose-dependent manner. The estrogen receptor (ER) β antagonist PHTPP completely inhibited CAPE-induced depolarization, but the ERα antagonist BHPI did not. Intracellular GDP-β-S and pretreatment with Ca2+-free solution or thapsigargin also blocked CAPE-induced depolarization. To investigate the mechanisms of CAPE-mediated depolarization of ICCs, we used the nonselective cation channel (NSCC) inhibitor flufenamic acid, the Cl- channel blocker, mitogen-activated protein kinase (MAPK) inhibitors PD98059, SB203580, or SP600125, and PI3 kinase inhibitor LY294002. All inhibitors blocked the CAPE-induced pacemaker potential depolarization of ICCs. These results suggest that CAPE induces pacemaker potential depolarization through ERβ in a G protein, NSCC, Cl- channel, MAPK- and PI3 kinase dependent manner via intracellular and extracellular Ca2+ regulation in the murine small intestine. CAPE may therefore modulate GI motility by acting on ICCs in the murine small intestine.
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Affiliation(s)
- Jeong Nam Kim
- Division of Longevity and Biofunctional Medicine, Pusan National University School of Korean Medicine, Yangsan 50612, Republic of Korea.,Healthy Aging Korean Medical Research Center, Pusan National University School of Korean Medicine, Yangsan 50612, Republic of Korea
| | - Byung Joo Kim
- Division of Longevity and Biofunctional Medicine, Pusan National University School of Korean Medicine, Yangsan 50612, Republic of Korea.,Healthy Aging Korean Medical Research Center, Pusan National University School of Korean Medicine, Yangsan 50612, Republic of Korea
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10
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Zhou Y, Wang J, Meng Z, Zhou S, Peng J, Chen S, Wang Q, Sun K. Pharmacology of Ivabradine and the Effect on Chronic Heart Failure. Curr Top Med Chem 2019; 19:1878-1901. [PMID: 31400267 DOI: 10.2174/1568026619666190809093144] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 07/02/2019] [Accepted: 07/25/2019] [Indexed: 11/22/2022]
Abstract
Chronic Heart Failure (CHF) is a complex clinical syndrome with a high incidence worldwide. Although various types of pharmacological and device therapies are available for CHF, the prognosis is not ideal, for which, the control of increased Heart Rate (HR) is critical. Recently, a bradycardic agent, ivabradine, is found to reduce HR by inhibiting the funny current (If). The underlying mechanism states that ivabradine can enter the Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels and bind to the intracellular side, subsequently inhibiting the If. This phenomenon can prolong the slow spontaneous phase in the diastolic depolarization, and thus, reduce HR. The clinical trials demonstrated the significant effects of the drug on reducing HR and improving the symptoms of CHF with fewer adverse effects. This review primarily introduces the chemical features and pharmacological characteristics of ivabradine and the mechanism of treating CHF. Also, some expected therapeutic effects on different diseases were also concluded. However, ivabradine, as a typical If channel inhibitor, necessitates additional research to verify its pharmacological functions.
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Affiliation(s)
- Yue Zhou
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Jian Wang
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Zhuo Meng
- Department of Pediatric Cardiology, the Second Affiliated Hospital&Yuying Children's Hospital of Wenzhou Medical University, Wenzhou 325000, China
| | - Shuang Zhou
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Jiayu Peng
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Sun Chen
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Qingjie Wang
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
| | - Kun Sun
- Department of Pediatric Cardiology, Xinhua Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200092, China
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11
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Youm JB, Zheng H, Koh SD, Sanders KM. Na-K-2Cl Cotransporter and Store-Operated Ca 2+ Entry in Pacemaking by Interstitial Cells of Cajal. Biophys J 2019; 117:767-779. [PMID: 31400920 DOI: 10.1016/j.bpj.2019.07.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/26/2019] [Accepted: 07/11/2019] [Indexed: 01/13/2023] Open
Abstract
Pacemaker depolarization in interstitial cells of Cajal (ICCs) is believed to be induced by Ca2+ transients and activation of anoctamin-1 (Ano1) channels in the plasma membrane. However, block of store-operated calcium entry (SOCE) or the Na-K-2Cl cotransporter (NKCC1) terminates pacemaker activity in ICC, indicating these transporters are involved in the initiation or maintenance of pacemaker activity. We hypothesized that SOCE contributes to pacemaker depolarization by maintaining [Ca2+] in the endoplasmic reticulum, which is the underlying source of Ca2+ transients for activation of Ano1. NKCC1 maintains the Cl- gradient supporting the driving force for inward current mediated by Ano1. Currently mechanisms sustaining release of Ca2+ and activation of Ano1 channels during the plateau phase of slow waves are unknown, but the reverse mode of the Na+/Ca2+ exchange may contribute. We generated a mathematical model of pacemaker activity based on current empirical observations from ICC of mouse small intestine that incorporates functions of SOCE and NKCC1. This model reproduces experimental findings, suggesting roles for SOCE and Ano1 channels: blocking of either NKCC1 or SOCE in our model terminates pacemaker activity. Direct contribution of NKCC1 to pacemaker activity in a beat-to-beat manner is not predicted by our model. Instead, NKCC1 plays a maintenance role supporting the driving force for Cl- efflux. Incorporation of SOCE allows the model to drive pacemaker activity without a diastolic depolarization, as observed in cardiac pacemaking. Further biological experiments are necessary to validate and further refine the roles of NKCC1, Na+/Ca2+ exchange, and Ano1 in the pacemaker mechanism of ICC.
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Affiliation(s)
- Jae Boum Youm
- Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea
| | - Haifeng Zheng
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada
| | - Sang Don Koh
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada
| | - Kenton M Sanders
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, Nevada.
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Chang X, Wang J, Jiang H, Shi L, Xie J. Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: An Emerging Role in Neurodegenerative Diseases. Front Mol Neurosci 2019; 12:141. [PMID: 31231190 PMCID: PMC6560157 DOI: 10.3389/fnmol.2019.00141] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Accepted: 05/13/2019] [Indexed: 12/13/2022] Open
Abstract
Neurodegenerative diseases such as Parkinson’s disease (PD), Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), and spinal muscular atrophy (SMA) are chronic, progressive, and age-associated neurological disorders characterized by neuronal deterioration in specific brain regions. Although the specific pathological mechanisms underlying these disorders have remained elusive, ion channel dysfunction has become increasingly accepted as a potential mechanism for neurodegenerative diseases. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are encoded by the HCN1-4 gene family and conduct the hyperpolarization-activated current (Ih). These channels play important roles in modulating cellular excitability, rhythmic activity, dendritic integration, and synaptic transmission. In the present review, we first provide a comprehensive picture of the role of HCN channels in PD by summarizing their role in the regulation of neuronal activity in PD-related brain regions. Dysfunction of Ih may participate in 1-methyl-4-phenylpyridinium (MPP+)-induced toxicity and represent a pathogenic mechanism in PD. Given current reports of the critical role of HCN channels in neuroinflammation and depression, we also discussed the putative contribution of HCN channels in inflammatory processes and non-motor symptoms in PD. In the second section, we summarize how HCN channels regulate the formation of β-amyloid peptide in AD and the role of these channels in learning and memory. Finally, we briefly discuss the effects of HCN channels in ALS and SMA based on existing discoveries.
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Affiliation(s)
- Xiaoli Chang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China.,Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Jun Wang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China.,Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Hong Jiang
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China.,Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Limin Shi
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China.,Institute of Brain Science and Disease, Qingdao University, Qingdao, China
| | - Junxia Xie
- Department of Physiology, Shandong Provincial Key Laboratory of Pathogenesis and Prevention of Neurological Disorders and State Key Disciplines: Physiology, Medical College of Qingdao University, Qingdao, China.,Institute of Brain Science and Disease, Qingdao University, Qingdao, China
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13
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Kim D, Kim JN, Nam JH, Lee JR, Kim SC, Kim BJ. Modulation of Pacemaker Potentials in Murine Small Intestinal Interstitial Cells of Cajal by Gamisoyo-San, a Traditional Chinese Herbal Medicine. Digestion 2018; 98:56-68. [PMID: 29672308 DOI: 10.1159/000487186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 01/22/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND The Gamisoyo-san (GSS) has been used for -improving the gastrointestinal (GI) symptoms. The purpose of this study was to investigate the effects of GSS, a traditional Chinese herbal medicine, on the pacemaker potentials of mouse small intestinal interstitial cells of Cajal (ICCs). METHODS ICCs from the small intestines were dissociated and cultured. Whole-cell patch-clamp configuration was used to record pacemaker potentials and membrane currents. RESULTS GSS depolarized ICC pacemaker potentials in a dose-dependent manner. Pretreatment with 4-diphenylacetoxypiperidinium iodide completely inhibited GSS-induced pacemaker potential depolarizations. Intracellular GDP-β-S inhibited GSS-induced effects, and in the presence of U-73122, GSS-induced effects were inhibited. Also, GSS in the presence of a Ca2+-free solution or thapsigargin did not depolarize pacemaker potentials. However, in the presence of calphostin C, GSS slightly depolarized pacemaker potentials. Furthermore, GSS inhibited both transient receptor potential melastatin7 and Ca2+-activated Cl- channel (anoctamin1) currents. CONCLUSION GSS depolarized pacemaker potentials of ICCs via G protein and muscarinic M3 receptor signaling pathways and through internal or external Ca2+-, phospholipase C-, and protein kinase C-dependent and transient receptor potential melastatin 7-, and anoctamin 1-independent pathways. The study shows that GSS may regulate GI tract motility, suggesting that GSS could be a basis for developing novel prokinetic agents for treating GI motility dysfunctions.
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Affiliation(s)
- Doeun Kim
- Division of Longevity and Biofunctional Medicine, Yangsan, Republic of Korea
| | - Jung Nam Kim
- Division of Longevity and Biofunctional Medicine, Yangsan, Republic of Korea.,Healthy Aging Korean Medical Research Center (HAKMRC), Pusan National University School of Korean Medicine, Yangsan, Republic of Korea
| | - Joo Hyun Nam
- Department of Physiology, College of Medicine, Dongguk University, Kyungju, Republic of Korea
| | - Jong Rok Lee
- Department of Pharmaceutical Engineering, Daegu Haany University, Gyeongsan, Republic of Korea
| | - Sang Chan Kim
- College of Oriental Medicine, Daegu Haany University, Gyeongsan, Republic of Korea
| | - Byung Joo Kim
- Division of Longevity and Biofunctional Medicine, Yangsan, Republic of Korea.,Healthy Aging Korean Medical Research Center (HAKMRC), Pusan National University School of Korean Medicine, Yangsan, Republic of Korea
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14
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Lord R, Fairbourn N, Mylavarapu C, Dbeis A, Bowman T, Chandrashekar A, Banayat T, Hodges CA, Al-Nakkash L. Consuming Genistein Improves Survival Rates in the Absence of Laxative in ΔF508-CF Female Mice. Nutrients 2018; 10:E1418. [PMID: 30282922 PMCID: PMC6213472 DOI: 10.3390/nu10101418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 09/11/2018] [Accepted: 09/26/2018] [Indexed: 11/16/2022] Open
Abstract
Genistein is a naturally occurring isoflavone found in soy. Genistein has been shown to increase the open probability of the most common cystic fibrosis (CF) disease-associated mutation, ∆F508-CFTR. Mice homozygous for the ∆F508 mutation are characterized with severe intestinal disease and require constant laxative treatment for survival. This pathology mimics the intestinal obstruction (meconium ileus) seen in some cystic fibrosis patients. This study tested whether dietary supplementation with genistein would reduce the dependence of the ∆F508 CF mouse model on laxatives for survival, thereby improving mortality rates. At weaning (21 days), homozygous ∆F508 mice were maintained on one of three diet regimens for a period of up to 65 days: normal diet, normal diet plus colyte, or genistein diet. Survival rates for males were as follows: standard diet (38%, n = 21), standard diet plus colyte (83%, n = 42) and genistein diet (60%, n = 15). Survival rates for females were as follows: standard diet (47%, n = 19), standard diet plus colyte (71%, n = 38), and genistein diet (87%, n = 15). Average weight of male mice fed genistein diet increased by ~2.5 g more (p = 0.006) compared to those with colyte treatment. Genistein diet did not change final body weight of females. Expression of intestinal SGLT-1 increased 2-fold (p = 0.0005) with genistein diet in females (no change in males, p = 0.722). Expression of GLUT2 and GLUT5 was comparable between all diet groups. Genistein diet reduced the number of goblet cells per micrometer of crypt depth in female (p = 0.0483), yet was without effect in males (p = 0.7267). The results from this study demonstrate that supplementation of diet with genistein for ~45 days increases the survival rate of female ∆F508-CF mice (precluding the requirement for laxatives), and genistein only improves weight gain in males.
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Affiliation(s)
- Ryan Lord
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Nathan Fairbourn
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Charisma Mylavarapu
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Ammer Dbeis
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Taylor Bowman
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Archana Chandrashekar
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Tatum Banayat
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
| | - Craig A Hodges
- Department of Genetics & Genome Sciences & Department of Pediatrics, Case Western Reserve University, 10900 Euclid Avenue, 830 BRB, Cleveland, OH 44106, USA.
| | - Layla Al-Nakkash
- Department of Physiology, AZCOM, Midwestern University, 19555 N. 59th Avenue, Glendale, AZ 85308, USA.
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15
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Mader F, Müller S, Krause L, Springer A, Kernig K, Protzel C, Porath K, Rackow S, Wittstock T, Frank M, Hakenberg OW, Köhling R, Kirschstein T. Hyperpolarization-Activated Cyclic Nucleotide-Gated Non-selective (HCN) Ion Channels Regulate Human and Murine Urinary Bladder Contractility. Front Physiol 2018; 9:753. [PMID: 29971015 PMCID: PMC6018223 DOI: 10.3389/fphys.2018.00753] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/29/2018] [Indexed: 11/16/2022] Open
Abstract
Purpose: Hyperpolarization-activated cyclic nucleotide gated non-selective (HCN) channels have been demonstrated in the urinary bladder in various species. Since they play a major role in governing rhythmic activity in pacemaker cells like in the sinoatrial node, we explored the role of these channels in human and murine detrusor smooth muscle. Methods: In an organ bath, human and murine detrusor smooth muscle specimens were challenged with the HCN channel blocker ZD7288. In human tissue derived from macroscopically tumor-free cancer resections, the urothelium was removed. In addition, HCN1-deficient mice were used to identify the contribution of this particular isoform. Expression of HCN channels in the urinary bladder was analyzed using histological and ultrastructural analyses as well as quantitative reverse transcriptase polymerase chain reaction (RT-PCR). Results: We found that the HCN channel blocker ZD7288 (50 μM) both induced tonic contractions and increased phasic contraction amplitudes in human and murine detrusor specimens. While these responses were not sensitive to tetrodotoxin, they were significantly reduced by the gap junction inhibitor 18β-glycyrrhetic acid suggesting that HCN channels are located within the gap junction-interconnected smooth muscle cell network rather than on efferent nerve fibers. Immunohistochemistry suggested HCN channel expression on smooth muscle tissue, and immunoelectron microscopy confirmed the scattered presence of HCN2 on smooth muscle cell membranes. HCN channels seem to be down-regulated with aging, which is paralleled by an increasing effect of ZD7288 in aging detrusor tissue. Importantly, the anticonvulsant and HCN channel activator lamotrigine relaxed the detrusor which could be reversed by ZD7288. Conclusion: These findings demonstrate that HCN channels are functionally present and localized on smooth muscle cells of the urinary bladder. Given the age-dependent decline of these channels in humans, activation of HCN channels by compounds such as lamotrigine opens up the opportunity to combat detrusor hyperactivity in the elderly by drugs already approved for epilepsy.
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Affiliation(s)
- Felix Mader
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Steffen Müller
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Ludwig Krause
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Armin Springer
- Department of Medical Biology, Electron Microscopy Center, University of Rostock, Rostock, Germany
| | - Karoline Kernig
- Department of Urology, University of Rostock, Rostock, Germany
| | - Chris Protzel
- Department of Urology, University of Rostock, Rostock, Germany
| | - Katrin Porath
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Simone Rackow
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Tristan Wittstock
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Marcus Frank
- Department of Medical Biology, Electron Microscopy Center, University of Rostock, Rostock, Germany
| | | | - Rüdiger Köhling
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
| | - Timo Kirschstein
- Oscar Langendorff Institute of Physiology, University of Rostock, Rostock, Germany
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16
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Synaptic transmission and excitability during hypoxia with inflammation and reoxygenation in hippocampal CA1 neurons. Neuropharmacology 2018; 138:20-31. [PMID: 29775678 DOI: 10.1016/j.neuropharm.2018.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/19/2018] [Accepted: 05/08/2018] [Indexed: 12/30/2022]
Abstract
Although a number of experimental and clinical studies have shown that hypoxia typically accompanies acute inflammatory responses, the combinatorial effect of the two insults on basic neural function has not been thoroughly investigated. Previous studies have predominantly suggested that hypoxia reduces network activity; however, several studies suggest the opposite effect. Of note, inflammation is known to increase neural activity. In the current study, we examined the effects of limited oxygen in combination with an inflammatory stimulus, as well as the effects of reoxygenation, on synaptic transmission and excitability. We observed a significant reduction of both synaptic transmission and excitability when hypoxia and inflammation occurred in combination, whereas reoxygenation caused hyperexcitability of neurons. Further, we found that the observed reduction in synaptic transmission was due to compromised presynaptic release efficiency based on an adenosine-receptor-dependent increase in synaptic facilitation. Excitability changes in both directions were attributable to dynamic regulation of the hyperpolarization-activated cation current (Ih) and to changes in the input resistance and the voltage difference between resting membrane potential and action potential threshold. We found that zatebradine, an Ih current inhibitor, reduced the fluctuation in excitability, suggesting that it may have potential as a drug to ameliorate reperfusion brain injury.
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17
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Naganuma S, Shiina T, Yasuda S, Suzuki Y, Shimizu Y. Histamine-enhanced contractile responses of gastric smooth muscle via interstitial cells of Cajal in the Syrian hamster. Neurogastroenterol Motil 2018; 30:e13255. [PMID: 29159902 DOI: 10.1111/nmo.13255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/28/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Gastric motility is controlled by the autonomic and enteric nervous systems and by interstitial cells of Cajal (ICCs). Although histamine is known to be released from enterochromaffin-like cells in the gastric mucosa, its regulatory roles in gastric motility are still controversial. Therefore, we investigated the functional roles of histamine in gastric motility. METHODS Stomach preparations from hamsters were used because the stomach of hamsters can be easily separated into the forestomach and the glandular stomach. A whole preparation of the stomach was mounted in a Magnus tube, and mechanical responses were recorded using a force transducer. KEY RESULTS Exogenous application of histamine had little effect on contractile activity of the glandular stomach. In contrast, the monoamine evoked regular, periodic contractions in the forestomach. An H1 receptor agonist reproduced the contractile responses and an H1 receptor antagonist blocked histamine-evoked contractions. Atropine and tetrodotoxin did not affect the histamine-evoked contractions. Pretreatment with drugs that inhibit the activity of ICCs abolished the effects of histamine. CONCLUSION & INFERENCES The findings suggest that histamine regulates gastric motility by acting on ICCs via H1 receptors in the hamster. The remarkable ability of histamine to induce rhythmic contractions would be useful for treatment of gastric dysmotility.
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Affiliation(s)
- S Naganuma
- Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - T Shiina
- Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - S Yasuda
- Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Y Suzuki
- Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Y Shimizu
- Department of Basic Veterinary Science, Laboratory of Physiology, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.,Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, Gifu, Japan
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18
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Fisher DW, Luu P, Agarwal N, Kurz JE, Chetkovich DM. Loss of HCN2 leads to delayed gastrointestinal motility and reduced energy intake in mice. PLoS One 2018; 13:e0193012. [PMID: 29466436 PMCID: PMC5821371 DOI: 10.1371/journal.pone.0193012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Accepted: 02/03/2018] [Indexed: 01/22/2023] Open
Abstract
Hyperpolarization-activated Cyclic Nucleotide-gated (HCN) channels are important regulators of excitability in neural, cardiac, and other pacemaking cells, which are often altered in disease. In mice, loss of HCN2 leads to cardiac dysrhythmias, persistent spike-wave discharges similar to those seen in absence epilepsy, ataxia, tremor, reduced neuropathic and inflammatory pain, antidepressant-like behavior, infertility, and severely restricted growth. While many of these phenotypes have tissue-specific mechanisms, the cause of restricted growth in HCN2 knockout animals remains unknown. Here, we characterize a novel, 3kb insertion mutation of Hcn2 in the Tremor and Reduced Lifespan 2 (TRLS/2J) mouse that leads to complete loss of HCN2 protein, and we show that this mutation causes many phenotypes similar to other mice lacking HCN2 expression. We then demonstrate that while TRLS/2J mice have low blood glucose levels and impaired growth, dysfunction in hormonal secretion from the pancreas, pituitary, and thyroid are unlikely to lead to this phenotype. Instead, we find that homozygous TRLS/2J mice have abnormal gastrointestinal function that is characterized by less food consumption and delayed gastrointestinal transit as compared to wildtype mice. In summary, a novel mutation in HCN2 likely leads to impaired GI motility, causing the severe growth restriction seen in mice with mutations that eliminate HCN2 expression.
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Affiliation(s)
- Daniel W. Fisher
- Davee Department of Neurology and Clinical Neurosciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States of America
| | - Phillip Luu
- Davee Department of Neurology and Clinical Neurosciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States of America
| | - Neha Agarwal
- Davee Department of Neurology and Clinical Neurosciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States of America
| | - Jonathan E. Kurz
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, IL, United States of America
| | - Dane M. Chetkovich
- Davee Department of Neurology and Clinical Neurosciences, Northwestern University Feinberg School of Medicine, Chicago, IL, United States of America
- Department of Neurology, Vanderbilt University Medical Center, Nashville, TN, United States of America
- * E-mail:
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19
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Liu Q, Wu C, Huang S, Wu Q, Zhou T, Liu X, Liu X, Hu X, Li L. Decreased hyperpolarization-activated cyclic nucleotide-gated channels are involved in bladder dysfunction associated with spinal cord injury. Int J Mol Med 2018; 41:2609-2618. [PMID: 29436607 PMCID: PMC5846662 DOI: 10.3892/ijmm.2018.3489] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 02/08/2018] [Indexed: 12/12/2022] Open
Abstract
Spinal cord injury (SCI) leads to bereft voluntary control of bladder, but the possible role of spontaneous excited system in bladder of SCI patients is poorly understood. Hyper polarization-activated cyclic nucleotide-gated (HCN) channels are deemed to regulate the spontaneous contraction of bladder, our study explored the functional role of HCN channels in SCI induced neurogenic bladder. Sixty female Sprague-Dawley rats were randomized into control, sham and SCI groups. Rat models subjected to SCI at S2 levels were successfully established and were assessed using hematoxylin and eosin staining and cystometry. In SCI rats, the mRNA and protein expression levels of HCN channels and the Ih density were significantly reduced, and expression levels of several bladder HCN1 channel regulatory proteins were also significantly changed. The effects of 50 µM forskolin and 50 µM 8-bromoadenosine 3′,5′-cyclic monophosphate on [Ca2+]i of isolated bladder interstitial cells of Cajal-like cells were significantly decreased in SCI rats. The spontaneous contractions in detrusor strips from SCI rats were significantly weakened. Furthermore, detrusor strips from SCI rats exhibited decreased tolerance to two doses of ZD7288 (10 and 50 µM). Taken together, our results indicate that the decreased bladder HCN channel expression and function induced by altered regulatory proteins are involved in the pathological process of SCI induced neurogenic bladder, which present HCN channels as valid therapeutic targets for treating this disease.
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Affiliation(s)
- Qian Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Chao Wu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Shengquan Huang
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Qingjian Wu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Tao Zhou
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xiaobing Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xin Liu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Xiaoyan Hu
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
| | - Longkun Li
- Department of Urology, The Second Affiliated Hospital, The Third Military Medical University, Chongqing 400037, P.R. China
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20
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Sartiani L, Mannaioni G, Masi A, Novella Romanelli M, Cerbai E. The Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: from Biophysics to Pharmacology of a Unique Family of Ion Channels. Pharmacol Rev 2017; 69:354-395. [PMID: 28878030 DOI: 10.1124/pr.117.014035] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/07/2017] [Indexed: 12/22/2022] Open
Abstract
Hyperpolarization-activated, cyclic nucleotide-gated (HCN) channels are important members of the voltage-gated pore loop channels family. They show unique features: they open at hyperpolarizing potential, carry a mixed Na/K current, and are regulated by cyclic nucleotides. Four different isoforms have been cloned (HCN1-4) that can assemble to form homo- or heterotetramers, characterized by different biophysical properties. These proteins are widely distributed throughout the body and involved in different physiologic processes, the most important being the generation of spontaneous electrical activity in the heart and the regulation of synaptic transmission in the brain. Their role in heart rate, neuronal pacemaking, dendritic integration, learning and memory, and visual and pain perceptions has been extensively studied; these channels have been found also in some peripheral tissues, where their functions still need to be fully elucidated. Genetic defects and altered expression of HCN channels are linked to several pathologies, which makes these proteins attractive targets for translational research; at the moment only one drug (ivabradine), which specifically blocks the hyperpolarization-activated current, is clinically available. This review discusses current knowledge about HCN channels, starting from their biophysical properties, origin, and developmental features, to (patho)physiologic role in different tissues and pharmacological modulation, ending with their present and future relevance as drug targets.
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Affiliation(s)
- Laura Sartiani
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Guido Mannaioni
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Alessio Masi
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Maria Novella Romanelli
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
| | - Elisabetta Cerbai
- Department of Neurosciences, Psychology, Drug Research, and Child Health, University of Florence, Firenze, Italy
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21
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Kim MW, Jiao HY, Kim SW, Park CG, Wu MJ, Hong C, Choi S, Jun JY. Prostanoid EP3 receptor agonist sulprostone enhances pacemaker activity of colonic interstitial cells of Cajal. Naunyn Schmiedebergs Arch Pharmacol 2017; 390:961-969. [PMID: 28685234 DOI: 10.1007/s00210-017-1398-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 06/28/2017] [Indexed: 10/19/2022]
Abstract
EP receptor activation by PGE2 regulates gastrointestinal motility by modulating smooth muscle contractility. Interstitial cells of Cajal (ICCs) are pacemaker cells that regulate smooth muscle activity. We aimed to determine effects of the EP3 receptor agonist sulprostone on pacemaker potentials in colonic ICCs. We performed a whole cell patch clamp, RT-PCR, and Ca2+ imaging in cultured ICCs from mouse colon. Sulprostone depolarized the membrane and increased pacemaker frequency. EP3 receptor antagonist blocked these sulprostone-induced effects. EP3 receptors were expressed in ANO1-positive ICCs. Phospholipase C inhibitor or Ca2+-ATPase inhibitor from the endoplasmic reticulum blocked the sulprostone-induced effects and sulprostone increased intracellular Ca2+ ([Ca2+]i) oscillations. Hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blockers also suppressed the sulprostone-induced effects. Sulprostone enhanced pacemaker activity through EP3 receptors by activating HCN channels via the [Ca2+]i release pathway. Therefore, EP3 receptor activation in ICCs may modulate colonic motility and could be a therapeutic target for enhancing colonic GI motility.
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Affiliation(s)
- Man Woo Kim
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, South Korea
| | - Han Yi Jiao
- Department of Physiology, College of Medicine, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 501-375, South Korea
| | - Seok Won Kim
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, South Korea
| | - Chan Guk Park
- Department of Internal Medicine, College of Medicine, Chosun University, Gwangju, South Korea
| | - Mei Jin Wu
- Department of Physiology, College of Medicine, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 501-375, South Korea
| | - Chansik Hong
- Department of Physiology, College of Medicine, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 501-375, South Korea
| | - Seok Choi
- Department of Physiology, College of Medicine, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 501-375, South Korea
| | - Jae Yeoul Jun
- Department of Physiology, College of Medicine, Chosun University, 309 Pilmun-daero, Dong-gu, Gwangju, 501-375, South Korea.
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ATP-sensitive K + channels maintain resting membrane potential in interstitial cells of Cajal from the mouse colon. Eur J Pharmacol 2017; 809:98-104. [PMID: 28511870 DOI: 10.1016/j.ejphar.2017.05.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/12/2017] [Accepted: 05/12/2017] [Indexed: 11/20/2022]
Abstract
To investigate the role of ATP-sensitive K+(KATP) channels on pacemaker activity in interstitial cells of Cajal (ICC), whole-cell patch clamping, RT-PCR, and intracellular Ca2+([Ca2+]i) imaging were performed in cultured colonic ICC. Pinacidil (a K+ channel opener) hyperpolarized the membrane and inhibited the generation of pacemaker potential, and this effect was reversed by glibenclamide (a KATP channel blocker). RT-PCR showed that Kir 6.1 and SUR2B were expressed in Ano-1 positive colonic ICC. Glibenclamide depolarized the membrane and increased pacemaker potential frequency. However, 5-hydroxydecanoic acid (a mitochondrial KATP channel blocker) had no effects on pacemaker potentials. Phorbol 12-myristate 13-acetate (PMA; a protein kinase C activator) blocked the pinacidil-induced effects, and PMA alone depolarized the membrane and increased pacemaker potential frequency. Cell-permeable 8-bromo-cyclic AMP also increased pacemaker potential frequency. Recordings of spontaneous intracellular Ca2+([Ca2+]i) oscillations showed that glibenclamide increased the frequency of [Ca2+]i oscillations. In small intestinal ICC, glibenclamide alone did not alter the generation of pacemaker potentials, and Kir 6.2 and SUR2B were expressed in Ano-1 positive ICC. Therefore, KATP channels in colonic ICC are activated in resting state and play an important role in maintaining resting membrane potential.
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Liu Q, Long Z, Dong X, Zhang T, Zhao J, Sun B, Zhu J, Li J, Wang Q, Yang Z, Hu X, Li L. Cyclophosphamide-induced HCN1 channel upregulation in interstitial Cajal-like cells leads to bladder hyperactivity in mice. Exp Mol Med 2017; 49:e319. [PMID: 28428632 PMCID: PMC6130216 DOI: 10.1038/emm.2017.31] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 12/05/2016] [Accepted: 12/07/2016] [Indexed: 12/20/2022] Open
Abstract
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are confirmed to be expressed in bladder interstitial Cajal-like cells (ICC-LCs), but little is known about their possible role in cystitis-associated bladder dysfunction. The present study aimed to determine the functional role of HCN channels in regulating bladder function under inflammatory conditions. Sixty female wild-type C57BL/6J mice and sixty female HCN1-knockout mice were randomly assigned to experimental and control groups, respectively. Cyclophosphamide (CYP)-induced cystitis models were successfully established in these mice. CYP treatment significantly enhanced HCN channel protein expression and Ih density and significantly altered bladder HCN1 channel regulatory proteins. Carbachol (CCH) and forskolin (FSK) exerted significant effects on bladder ICC-LC [Ca2+]i in CYP-treated wild-type (WT) mice, and HCN1 channel ablation significantly decreased the effects of CCH and FSK on bladder ICC-LC [Ca2+]i in both naive and CYP-treated mice. CYP treatment significantly potentiated the spontaneous contractions and CCH (0.001–10 μM)-induced phasic contractions of detrusor strips, and HCN1 channel deletion significantly abated such effects. Finally, we demonstrated that the development of CYP-induced bladder overactivity was reversed in HCN1−/− mice. Taken together, our results suggest that CYP-induced enhancements of HCN1 channel expression and function in bladder ICC-LCs are essential for cystitis-associated bladder hyperactivity development, indicating that the HCN1 channel may be a novel therapeutic target for managing bladder hyperactivity.
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Affiliation(s)
- Qian Liu
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Zhou Long
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Xingyou Dong
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Teng Zhang
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Jiang Zhao
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Bishao Sun
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Jingzhen Zhu
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Jia Li
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Qingqing Wang
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Zhenxing Yang
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Xiaoyan Hu
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Longkun Li
- Department of Urology, Second Affiliated Hospital, Third Military Medical University, Chongqing, China
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Lee MY, Ha SE, Park C, Park PJ, Fuchs R, Wei L, Jorgensen BG, Redelman D, Ward SM, Sanders KM, Ro S. Transcriptome of interstitial cells of Cajal reveals unique and selective gene signatures. PLoS One 2017; 12:e0176031. [PMID: 28426719 PMCID: PMC5398589 DOI: 10.1371/journal.pone.0176031] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 04/04/2017] [Indexed: 01/18/2023] Open
Abstract
Transcriptome-scale data can reveal essential clues into understanding the underlying molecular mechanisms behind specific cellular functions and biological processes. Transcriptomics is a continually growing field of research utilized in biomarker discovery. The transcriptomic profile of interstitial cells of Cajal (ICC), which serve as slow-wave electrical pacemakers for gastrointestinal (GI) smooth muscle, has yet to be uncovered. Using copGFP-labeled ICC mice and flow cytometry, we isolated ICC populations from the murine small intestine and colon and obtained their transcriptomes. In analyzing the transcriptome, we identified a unique set of ICC-restricted markers including transcription factors, epigenetic enzymes/regulators, growth factors, receptors, protein kinases/phosphatases, and ion channels/transporters. This analysis provides new and unique insights into the cellular and biological functions of ICC in GI physiology. Additionally, we constructed an interactive ICC genome browser (http://med.unr.edu/physio/transcriptome) based on the UCSC genome database. To our knowledge, this is the first online resource that provides a comprehensive library of all known genetic transcripts expressed in primary ICC. Our genome browser offers a new perspective into the alternative expression of genes in ICC and provides a valuable reference for future functional studies.
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Affiliation(s)
- Moon Young Lee
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do, Korea
| | - Se Eun Ha
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Paul J. Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Robert Fuchs
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Lai Wei
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Brian G. Jorgensen
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Doug Redelman
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Sean M. Ward
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- * E-mail:
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Alotaibi M, Kahlat K, Nedjadi T, Djouhri L. Effects of ZD7288, a hyperpolarization-activated cyclic nucleotide-gated (HCN) channel blocker, on term-pregnant rat uterine contractility in vitro. Theriogenology 2017; 90:141-146. [DOI: 10.1016/j.theriogenology.2016.11.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2016] [Revised: 11/22/2016] [Accepted: 11/24/2016] [Indexed: 12/01/2022]
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EP3 activation facilitates bladder excitability via HCN channels on ICCs. Biochem Biophys Res Commun 2017; 485:535-541. [PMID: 28131828 DOI: 10.1016/j.bbrc.2017.01.131] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 01/23/2017] [Indexed: 12/20/2022]
Abstract
EP3 is a receptor for prostaglandin E2 (PGE2), and although its effect on bladder excitability has attracted considerable attention, the underlying mechanism remains unclear. To investigate whether the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in the interstitial cells of Cajal (ICCs) of the bladder are involved in the effect of EP3 activation on bladder excitability, wild-type mice, HCN1 knockout (HCN1-/-) mice and rats were used in our study. Double immunofluorescence staining and immunoprecipitation assays demonstrated the interaction between EP3 and the HCN channels. Sulprostone is a selective agonist of EP3. The current density of HCN channels was enhanced by sulprostone or PGE2 using whole-cell patch clamping. Western blot analyses showed that the expression levels of HCN1 and HCN4 were higher in bladders that had undergone intravesical instillation with sulprostone than in bladders treated with normal saline (NS). Both PGE2 and sulprostone increased the calcium concentration of the ICCs, and their effects were inhibited by ZD7288 (antagonist of HCN channels) treatment. In bladder detrusor strip testing, both PGE2 and sulprostone enhanced the amplitude of the bladder detrusor in HCN1-/- mice; however, these effects were less than those in the wild-type mice. Furthermore, the effects of PGE2 and sulprostone were inhibited by ZD7288. Taken together, our results indicate that EP3 is expressed in bladder ICCs and facilitates bladder excitability via HCN channels. This study provides more comprehensive insights into the mechanism between inflammation and bladder excitability and highlights methods that can resolve bladder hyperactivity.
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Guo T, Li J, Li J, Kong D, Bi C, He Z, Tang D, Jin X, Jin L. Association between hyperpolarization-activated channel in interstitial cells of Cajal and gastrointestinal dysmotility induced by malignant ascites. Oncol Lett 2017; 13:1601-1608. [PMID: 28454297 PMCID: PMC5403200 DOI: 10.3892/ol.2017.5652] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 11/03/2016] [Indexed: 12/20/2022] Open
Abstract
Advanced malignant ascites is accompanied by gastrointestinal dysmotility, and patients often feel abdominal pain, abdominal distention, nausea and constipation. Gastrointestinal dysmotility is not only painful for the patients, but it reduces the absorption of nutrients and affects the physical recovery of patients with malignant ascites. It is reported that changes in interstitial cells of Cajal (ICCs) are responsible for the gastrointestinal dysmotility induced by malignant ascites, but the mechanism is not completely understood. The present study observed a significantly decreased expression of ion channels, including hyperpolarization-activated cyclic nucleotide-gated potassium channel 2 (HCN2) and cyclic adenosine monophosphate, in the condition of malignant ascites. Using electrophysiology, it was identified that malignant ascites led to lower amplitude and slower frequency signals in cells of the small intestine. In addition, when ICCs were cultured with malignant ascites in vitro, the expression of HCN2 of ICCs was significantly reduced, and the data of flow cytometry revealed that the Ca2+ concentration of ICCs was also decreased. The results of electron microscopy analysis demonstrated the nuclei of ICCs were pyknotic, and the processes of ICCs were reduced in malignant ascites. The present study suggests the small intestinal dysmotility caused by malignant ascites may be associated with changes in HCN2 of ICCs, which offers a potential therapeutic target for gastrointestinal dysmotility in advanced malignant ascites.
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Affiliation(s)
- Tieyun Guo
- Department of Histology and Embryology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Jiade Li
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Jing Li
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Dan Kong
- Department of Gynecology, The Third Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Chunli Bi
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Zheng He
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Dai Tang
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Xiaoming Jin
- Department of Pathology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
| | - Lianhong Jin
- Department of Histology and Embryology, Basic Medical Science College, Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China
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28
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Lin XL, Tang XD, Cai ZX, Wang FY, Li P, Sui H, Guo HS. NPs/NPRs Signaling Pathways May Be Involved in Depression-Induced Loss of Gastric ICC by Decreasing the Production of mSCF. PLoS One 2016; 11:e0149031. [PMID: 26862759 PMCID: PMC4749124 DOI: 10.1371/journal.pone.0149031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Accepted: 01/25/2016] [Indexed: 12/13/2022] Open
Abstract
It is well known that natriuretic peptides (NPs) are involved in the regulation of gastrointestinal motility. Interstitial cells of Cajal (ICC) are the pacemaker cells of gastrointestinal motility and gastrointestinal dyskinesia is one of the important digestive tract symptoms of depression. However, it is unclear whether they are involved in depression-induced loss of ICC. The aim of the present study was to investigate the relationship between the natriuretic peptide signaling pathway and depression-induced loss of gastric ICC in depressed rats. These results showed that the expression of c-kit and stem cell factor (SCF) in smooth muscle layers of stomach were down-regulated in depressed rats at the mRNA and protein levels. The expression of natriuretic peptide receptor (NPR)-A, B and C were up-regulated in the stomach of depressed rats at the mRNA and protein levels. NPR-A, B and C can significantly decrease the expression of SCF to treat cultured gastric smooth muscle cells (GSMCs) obtained from normal rats with different concentrations of C-type natriuretic peptide (CNP). Pretreatment of cultured GSMCs with 8-Brom-cGMP (8-Br-cGMP, a membrane permeable cGMP analog), cANF (a specific NPR-C agonist) and CNP (10−6 mol/L) demonstrated that 8-Br-cGMP had a similar effect as CNP, but treatment with cANF did not. The results of the methyl thiazolyl tetrazolium bromide (MTT) assay indicated that high concentrations of cANF (10−6 mol/L) restrained the proliferation of cultured GSMCs. Taken together, these results indicate that the up-regulation of the NPs/NPR-C and NPs/NPR-A, B/cGMP signaling pathways may be involved in depression-induced loss of gastric ICC.
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Affiliation(s)
- Xue-Lian Lin
- Central Laboratory, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning Province, China
| | - Xu-Dong Tang
- Department of Gastroenterology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, 100091, China
| | - Zheng-Xu Cai
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning Province, China
- * E-mail: (HSG); (ZXC)
| | - Feng-Yun Wang
- Department of Gastroenterology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, 100091, China
| | - Ping Li
- Central Laboratory, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning Province, China
| | - Hua Sui
- Institute of Basic Research of Integrative Medicine, Dalian Medical University, Dalian, 116044, Liaoning Province, China
| | - Hui-Shu Guo
- Central Laboratory, The First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning Province, China
- * E-mail: (HSG); (ZXC)
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Banciu DD, Banciu A, Radu BM. Electrophysiological Features of Telocytes. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 913:287-302. [PMID: 27796895 DOI: 10.1007/978-981-10-1061-3_19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Telocytes (TCs) are interstitial cells described in multiple structures, including the gastrointestinal tract, respiratory tract, urinary tract, uterus, and heart. Several studies have indicated the possibility that TCs are involved in the pacemaker potential in these organs. It is supposed that TCs are interacting with the neighboring muscular cells and their network contributes to the initiation and propagation of the electrical potentials. In order to understand the contribution of TCs to various excitability mechanisms, it is necessary to analyze the plasma membrane proteins (e.g., ion channels) functionally expressed in these cells. So far, potassium, calcium, and chloride currents, but not sodium currents, have been described in TCs in primary cell culture from different tissues. Moreover, TCs have been described as sensors for mechanical stimuli (e.g., contraction, extension, etc.). In conclusion, TCs might play an essential role in gastrointestinal peristalsis, in respiration, in pregnant uterus contraction, or in miction, but further highlighting studies are necessary to understand the molecular mechanisms and the cell-cell interactions by which TCs contribute to the tissue excitability and pacemaker potentials initiation/propagation.
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Affiliation(s)
- Daniel Dumitru Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, Bucharest, 050095, Romania
| | - Adela Banciu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, Bucharest, 050095, Romania
| | - Beatrice Mihaela Radu
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, Bucharest, 050095, Romania. .,Department of Neurological and Movement Sciences, University of Verona, Strada Le Grazie 8, Verona, 37134, Italy.
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Wu MJ, Shin DH, Kim MY, Park CG, Kim YD, Lee J, Park IK, Choi S, So I, Park JS, Jun JY. Functional effects of β3-adrenoceptor on pacemaker activity in interstitial cells of Cajal from the mouse colon. Eur J Pharmacol 2015; 754:32-40. [DOI: 10.1016/j.ejphar.2015.02.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 02/16/2015] [Accepted: 02/17/2015] [Indexed: 10/24/2022]
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Modeling of stochastic behavior of pacemaker potential in interstitial cells of Cajal. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2014; 116:56-69. [PMID: 25238716 DOI: 10.1016/j.pbiomolbio.2014.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 08/28/2014] [Accepted: 09/06/2014] [Indexed: 01/20/2023]
Abstract
It is widely accepted that interstitial cells of Cajal (ICCs) generate pacemaker potentials to propagate slow waves along the whole gastrointestinal tract. Previously, we constructed a biophysically based model of ICCs in mouse small intestine to explain the pacemaker mechanism. Our previous model, however, could not explain non-uniformity of pacemaker potentials and random occurrence of unitary potentials, thus we updated our model. The inositol 1,4,5-trisphosphate (IP3)-mediated Ca(2+) mobilization is a key event to drive the cycle of pacemaker activity and was updated to reproduce its stochastic behavior. The stochasticity was embodied by simulating random opening and closing of individual IP3-mediated Ca(2+) channel. The updated model reproduces the stochastic features of pacemaker potentials in ICCs. Reproduced pacemaker potentials are not uniform in duration and interval. The resting and peak potentials are -75.5 ± 1.1 mV and -0.8 ± 0.5 mV, respectively (n = 55). Frequency of pacemaker potential is 14.3 ± 0.4 min(-1) (n = 10). Width at half-maximal amplitude of pacemaker potential is 902 ± 6 ms (n = 55). There are random events of unitary potential-like depolarization. Finally, we compared our updated model with a recently published model to speculate which ion channel is the best candidate to drive pacemaker depolarization. In conclusion, our updated mathematical model could now reproduce stochastic features of pacemaker activity in ICCs.
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Basal cGMP regulates the resting pacemaker potential frequency of cultured mouse colonic interstitial cells of Cajal. Naunyn Schmiedebergs Arch Pharmacol 2014; 387:641-8. [PMID: 24676911 DOI: 10.1007/s00210-014-0976-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 03/17/2014] [Indexed: 01/01/2023]
Abstract
Cyclic guanosine 3',5'-monophosphate (cGMP) inhibited the generation of pacemaker activity in interstitial cells of Cajal (ICCs) from the small intestine. However, cGMP role on pacemaker activity in colonic ICCs has not been reported yet. Thus, we investigated the role of cGMP in pacemaker activity regulation by colonic ICCs. We performed a whole-cell patch-clamp and Ca(2+) imaging in cultured ICCs from mouse colon. 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ, an inhibitor of guanylate cyclase) increased the pacemaker potential frequency, whereas zaprinast (an inhibitor of phosphodiesterase) and cell-permeable 8-bromo-cGMP decreased the pacemaker potential frequency. KT-5823 (an inhibitor of protein kinase G [PKG]) did not affect the pacemaker potential. L-N(G)-nitroarginine methyl ester (L-NAME, an inhibitor of nitric oxide [NO] synthase) increased the pacemaker potential frequency, whereas (±)-S-nitroso-N-acetylpenicillamine (SNAP, a NO donor) decreased the pacemaker potential frequency. Glibenclamide (an ATP-sensitive K(+) channel blocker) did not block the effects of cell-permeable 8-bromo-cGMP and SNAP. Recordings of spontaneous intracellular Ca(2+) ([Ca(2+)]i) oscillations revealed that ODQ and L-NAME increased [Ca(2+)]i oscillations. In contrast, zaprinast, 8-bromo cGMP, and SNAP decreased the [Ca(2+)]i oscillations. Basal cGMP levels regulate the resting pacemaker potential frequency by the alteration on Ca(2+) release via a PKG-independent pathway. Additionally, the endogenous release of NO seems to be responsible maintaining basal cGMP levels in colonic ICCs.
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