1
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Whelan SCM, Mutchler SM, Han A, Priestley C, Satlin LM, Kleyman TR, Shi S. Kcnma1 alternative splicing in mouse kidney: regulation during development and by dietary K + intake. Am J Physiol Renal Physiol 2024; 327:F49-F60. [PMID: 38779757 DOI: 10.1152/ajprenal.00100.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 04/30/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024] Open
Abstract
The pore-forming α-subunit of the large-conductance K+ (BK) channel is encoded by a single gene, KCNMA1. BK channel-mediated K+ secretion in the kidney is crucial for overall renal K+ homeostasis in both physiological and pathological conditions. BK channels achieve phenotypic diversity by various mechanisms, including substantial exon rearrangements at seven major alternative splicing sites. However, KCNMA1 alternative splicing in the kidney has not been characterized. The present study aims to identify the major splice variants of mouse Kcnma1 in whole kidney and distal nephron segments. We designed primers that specifically cross exons within each alternative splice site of mouse Kcnma1 and performed real-time quantitative RT-PCR (RT-qPCR) to quantify relative abundance of each splice variant. Our data suggest that Kcnma1 splice variants within mouse kidney are less diverse than in the brain. During postnatal kidney development, most Kcnma1 splice variants at site 5 and the COOH terminus increase in abundance over time. Within the kidney, the regulation of Kcnma1 alternative exon splicing within these two sites by dietary K+ loading is both site and sex specific. In microdissected distal tubules, the Kcnma1 alternative splicing profile, as well as its regulation by dietary K+, are distinctly different than in the whole kidney, suggesting segment and/or cell type specificity in Kcnma1 splicing events. Overall, our data provide evidence that Kcnma1 alternative splicing is regulated during postnatal development and may serve as an important adaptive mechanism to dietary K+ loading in mouse kidney.NEW & NOTEWORTHY We identified the major Kcnma1 splice variants that are specifically expressed in the whole mouse kidney or aldosterone-sensitive distal nephron segments. Our data suggest that Kcnma1 alternative splicing is developmentally regulated and subject to changes in dietary K+.
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Affiliation(s)
| | - Stephanie M Mutchler
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Agnes Han
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Catherine Priestley
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Lisa M Satlin
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, New York, United States
| | - Thomas R Kleyman
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
| | - Shujie Shi
- Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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2
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He J, Xie X, Xiao Z, Qian W, Zhang L, Hou X. Piezo1 in Digestive System Function and Dysfunction. Int J Mol Sci 2023; 24:12953. [PMID: 37629134 PMCID: PMC10454946 DOI: 10.3390/ijms241612953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/13/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Piezo1, a non-selective cation channel directly activated by mechanical forces, is widely expressed in the digestive system and participates in biological functions physiologically and pathologically. In this review, we summarized the latest insights on Piezo1's cellular effect across the entire digestive system, and discussed the role of Piezo1 in various aspects including ingestion and digestion, material metabolism, enteric nervous system, intestinal barrier, and inflammatory response within digestive system. The goal of this comprehensive review is to provide a solid foundation for future research about Piezo1 in digestive system physiologically and pathologically.
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Affiliation(s)
| | | | | | | | - Lei Zhang
- Department of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (J.H.); (X.X.); (Z.X.); (W.Q.)
| | - Xiaohua Hou
- Department of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China; (J.H.); (X.X.); (Z.X.); (W.Q.)
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3
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Maqoud F, Tricarico D, Mallamaci R, Orlando A, Russo F. The Role of Ion Channels in Functional Gastrointestinal Disorders (FGID): Evidence of Channelopathies and Potential Avenues for Future Research and Therapeutic Targets. Int J Mol Sci 2023; 24:11074. [PMID: 37446251 DOI: 10.3390/ijms241311074] [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: 05/31/2023] [Revised: 06/29/2023] [Accepted: 06/30/2023] [Indexed: 07/15/2023] Open
Abstract
Several gastrointestinal (GI) tract abnormalities, including visceral hypersensitivity, motility, and intestinal permeability alterations, have been implicated in functional GI disorders (FGIDs). Ion channels play a crucial role in all the functions mentioned above. Hormones and natural molecules modulate these channels and represent targets of drugs and bacterial toxins. Mutations and abnormal functional expression of ion channel subunits can lead to diseases called channelopathies. These channelopathies in gastroenterology are gaining a strong interest, and the evidence of co-relationships is increasing. In this review, we describe the correlation status between channelopathies and FGIDs. Different findings are available. Among others, mutations in the ABCC7/CFTR gene have been described as a cause of constipation and diarrhea. Mutations of the SCN5A gene are instead associated with irritable bowel syndrome. In contrast, mutations of the TRPV1 and TRPA genes of the transient receptor potential (TRP) superfamily manifest hypersensitivity and visceral pain in sensory nerves. Recently, mice and humans affected by Cantu syndrome (CS), which is associated with the mutations of the KCNJ8 and ABCC9 genes encoding for the Kir6.1 and SUR2 subunits, showed dysfunction of contractility throughout the intestine and death in the mice after the weaning on solid food. The discovery of a correlation between channelopathies and FIGD opens new avenues for discovering new direct drug targets for specific channelopathies, leading to significant implications for diagnosing and treating functional GI diseases.
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Affiliation(s)
- Fatima Maqoud
- Functional Gastrointestinal Disorders Research Group, National Institute of Gastroenterology IRCCS "Saverio de Bellis", Castellana Grotte, 70013 Bari, Italy
| | - Domenico Tricarico
- Section of Pharmacology, Department of Pharmacy-Pharmaceutical Sciences, University of Bari Aldo Moro, 70125 Bari, Italy
| | - Rosanna Mallamaci
- Department of Biosciences, Biotechnologies and Environment University of Bari Aldo Moro, 70125 Bari, Italy
| | - Antonella Orlando
- Functional Gastrointestinal Disorders Research Group, National Institute of Gastroenterology IRCCS "Saverio de Bellis", Castellana Grotte, 70013 Bari, Italy
| | - Francesco Russo
- Functional Gastrointestinal Disorders Research Group, National Institute of Gastroenterology IRCCS "Saverio de Bellis", Castellana Grotte, 70013 Bari, Italy
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4
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Davis MJ, Earley S, Li YS, Chien S. Vascular mechanotransduction. Physiol Rev 2023; 103:1247-1421. [PMID: 36603156 PMCID: PMC9942936 DOI: 10.1152/physrev.00053.2021] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/26/2022] [Accepted: 10/04/2022] [Indexed: 01/07/2023] Open
Abstract
This review aims to survey the current state of mechanotransduction in vascular smooth muscle cells (VSMCs) and endothelial cells (ECs), including their sensing of mechanical stimuli and transduction of mechanical signals that result in the acute functional modulation and longer-term transcriptomic and epigenetic regulation of blood vessels. The mechanosensors discussed include ion channels, plasma membrane-associated structures and receptors, and junction proteins. The mechanosignaling pathways presented include the cytoskeleton, integrins, extracellular matrix, and intracellular signaling molecules. These are followed by discussions on mechanical regulation of transcriptome and epigenetics, relevance of mechanotransduction to health and disease, and interactions between VSMCs and ECs. Throughout this review, we offer suggestions for specific topics that require further understanding. In the closing section on conclusions and perspectives, we summarize what is known and point out the need to treat the vasculature as a system, including not only VSMCs and ECs but also the extracellular matrix and other types of cells such as resident macrophages and pericytes, so that we can fully understand the physiology and pathophysiology of the blood vessel as a whole, thus enhancing the comprehension, diagnosis, treatment, and prevention of vascular diseases.
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Affiliation(s)
- Michael J Davis
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri
| | - Scott Earley
- Department of Pharmacology, University of Nevada, Reno, Nevada
| | - Yi-Shuan Li
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
| | - Shu Chien
- Department of Bioengineering, University of California, San Diego, California
- Institute of Engineering in Medicine, University of California, San Diego, California
- Department of Medicine, University of California, San Diego, California
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5
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Cavin JB, Wongkrasant P, Glover JB, Balemba OB, MacNaughton WK, Sharkey KA. Intestinal distension orchestrates neuronal activity in the enteric nervous system of adult mice. J Physiol 2023; 601:1183-1206. [PMID: 36752210 PMCID: PMC10319177 DOI: 10.1113/jp284171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 01/17/2023] [Indexed: 02/09/2023] Open
Abstract
The enteric nervous system (ENS) regulates the motor, secretory and defensive functions of the gastrointestinal tract. Enteric neurons integrate mechanical and chemical inputs from the gut lumen to generate complex motor outputs. How intact enteric neural circuits respond to changes in the gut lumen is not well understood. We recorded intracellular calcium in live-cell confocal recordings in neurons from intact segments of mouse intestine in order to investigate neuronal response to luminal mechanical and chemical stimuli. Wnt1-, ChAT- and Calb1-GCaMP6 mice were used to record neurons from the jejunum and colon. We measured neuronal calcium response to KCl (75 mM), veratridine (10 μM), 1,1-dimethyl-4-phenylpiperazinium (DMPP; 100 μM) or luminal nutrients (Ensure®), in the presence or absence of intraluminal distension. In the jejunum and colon, distension generated by the presence of luminal content (chyme and faecal pellets, respectively) renders the underlying enteric circuit unresponsive to depolarizing stimuli. In the distal colon, high levels of distension inhibit neuronal response to KCl, while intermediate levels of distension reorganize Ca2+ response in circumferentially propagating slow waves. Mechanosensitive channel inhibition suppresses distension-induced Ca2+ elevations, and calcium-activated potassium channel inhibition restores neuronal response to KCl, but not DMPP in the distended colon. In the jejunum, distension prevents a previously unknown tetrodotoxin-resistant neuronal response to luminal nutrient stimulation. Our results demonstrate that intestinal distension regulates the excitability of ENS circuits via mechanosensitive channels. Physiological levels of distension locally silence or synchronize neurons, dynamically regulating the excitability of enteric neural circuits based on the content of the intestinal lumen. KEY POINTS: How the enteric nervous system of the gastrointestinal tract responds to luminal distension remains to be fully elucidated. Here it is shown that intestinal distension modifies intracellular calcium levels in the underlying enteric neuronal network, locally and reversibly silencing neurons in the distended regions. In the distal colon, luminal distension is integrated by specific mechanosensitive channels and coordinates the dynamics of neuronal activation within the enteric network. In the jejunum, distension suppresses the neuronal calcium responses induced by luminal nutrients. Physiological levels of distension dynamically regulate the excitability of enteric neuronal circuits.
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Affiliation(s)
- Jean-Baptiste Cavin
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Preedajit Wongkrasant
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Joel B Glover
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- Live Cell Imaging Laboratory, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Onesmo B Balemba
- Department of Biological Sciences, University of Idaho, Moscow, ID, USA
| | - Wallace K MacNaughton
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- Inflammation Research Network, University of Calgary, Calgary, Alberta, Canada
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
| | - Keith A Sharkey
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
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6
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Kola JB, Docsa T, Uray K. Mechanosensing in the Physiology and Pathology of the Gastrointestinal Tract. Int J Mol Sci 2022; 24:ijms24010177. [PMID: 36613619 PMCID: PMC9820522 DOI: 10.3390/ijms24010177] [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: 10/02/2022] [Revised: 12/10/2022] [Accepted: 12/17/2022] [Indexed: 12/24/2022] Open
Abstract
Normal gastrointestinal function relies on sensing and transducing mechanical signals into changes in intracellular signaling pathways. Both specialized mechanosensing cells, such as certain enterochromaffin cells and enteric neurons, and non-specialized cells, such as smooth muscle cells, interstitial cells of Cajal, and resident macrophages, participate in physiological and pathological responses to mechanical signals in the gastrointestinal tract. We review the role of mechanosensors in the different cell types of the gastrointestinal tract. Then, we provide several examples of the role of mechanotransduction in normal physiology. These examples highlight the fact that, although these responses to mechanical signals have been known for decades, the mechanosensors involved in these responses to mechanical signals are largely unknown. Finally, we discuss several diseases involving the overstimulation or dysregulation of mechanotransductive pathways. Understanding these pathways and identifying the mechanosensors involved in these diseases may facilitate the identification of new drug targets to effectively treat these diseases.
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Affiliation(s)
- Job Baffin Kola
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Center of Excellence, The Hungarian Academy of Sciences, 4032 Debrecen, Hungary
| | - Tibor Docsa
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Center of Excellence, The Hungarian Academy of Sciences, 4032 Debrecen, Hungary
| | - Karen Uray
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- Center of Excellence, The Hungarian Academy of Sciences, 4032 Debrecen, Hungary
- Correspondence:
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7
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Wang M, Li S, Liu H, Liu M, Zhang J, Wu Y, Xiao C, Huang H. Large-conductance Ca 2 +-activated K + channel β1-subunit maintains the contractile phenotype of vascular smooth muscle cells. Front Cardiovasc Med 2022; 9:1062695. [PMID: 36568562 PMCID: PMC9780463 DOI: 10.3389/fcvm.2022.1062695] [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: 10/06/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
Background Vascular smooth muscle cells (VSMCs) phenotype switching is very important during the pathogenesis and progression of vascular diseases. However, it is not well understood how normal VSMCs maintain the differentiated state. The large-conductance Ca2+-activated K+ (BKCa) channels are widely expressed in VSMCs and regulate vascular tone. Nevertheless, there is limited understanding of the role of the BKCa channel in modulation of the VSMC phenotype. Methods and results We assessed BKCa channel expression levels in normal and injured carotid arteries from rats of the balloon-injury model. A strong decrease of BKCa-β1 was seen in the injured carotid arteries, accompanied by a parallel decrease of the VSMC contractile markers. BKCa-β1 in primary rat aortic VSMCs was decreased with the increase of passage numbers and the stimulation of platelet-derived growth factor (PDGF)-BB. Conversely, transforming growth factor β upregulated BKCa-β1. Meanwhile, the BKCa-β1 level was positively associated with the levels of VSMC contractile proteins. Intravenous injection of PDGF-BB induced downregulation of BKCa-β1 expression in the carotid arteries. Knockdown of BKCa-β1 favored VSMC dedifferentiation, characterized by altered morphology, abnormal actin fiber organization, decreased contractile proteins expression and reduced contractile ability. Furthermore, the resultant VSMC dedifferentiated phenotype rendered increased proliferation, migration, enhanced inflammatory factors levels, and matrix metalloproteinases activity. Studies using primary cultured aortic VSMCs from human recapitulated key findings. Finally, protein level of BKCa-β1 was reduced in human atherosclerotic arteries. Conclusion BKCa-β1 is important in the maintenance of the contractile phenotype of VSMCs. As a novel endogenous defender that prevents pathological VSMC phenotype switching, BKCa-β1 may serve as a potential therapeutic target for treating vascular diseases including post-injury restenosis and atherosclerosis.
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Affiliation(s)
- Meili Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Shuanglei Li
- Division of Adult Cardiac Surgery, Department of Cardiology, The Sixth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Hongshan Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Mingyuan Liu
- Department of Vascular Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jin Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Yang Wu
- Division of Adult Cardiac Surgery, Department of Cardiology, The Sixth Medical Center, Chinese PLA General Hospital, Beijing, China
| | - Cangsong Xiao
- Division of Adult Cardiac Surgery, Department of Cardiology, The Sixth Medical Center, Chinese PLA General Hospital, Beijing, China,Cangsong Xiao,
| | - Haixia Huang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China,*Correspondence: Haixia Huang,
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8
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Yang H, Hou C, Xiao W, Qiu Y. The role of mechanosensitive ion channels in the gastrointestinal tract. Front Physiol 2022; 13:904203. [PMID: 36060694 PMCID: PMC9437298 DOI: 10.3389/fphys.2022.904203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 07/19/2022] [Indexed: 11/13/2022] Open
Abstract
Mechanosensation is essential for normal gastrointestinal (GI) function, and abnormalities in mechanosensation are associated with GI disorders. There are several mechanosensitive ion channels in the GI tract, namely transient receptor potential (TRP) channels, Piezo channels, two-pore domain potassium (K2p) channels, voltage-gated ion channels, large-conductance Ca2+-activated K+ (BKCa) channels, and the cystic fibrosis transmembrane conductance regulator (CFTR). These channels are located in many mechanosensitive intestinal cell types, namely enterochromaffin (EC) cells, interstitial cells of Cajal (ICCs), smooth muscle cells (SMCs), and intrinsic and extrinsic enteric neurons. In these cells, mechanosensitive ion channels can alter transmembrane ion currents in response to mechanical forces, through a process known as mechanoelectrical coupling. Furthermore, mechanosensitive ion channels are often associated with a variety of GI tract disorders, including irritable bowel syndrome (IBS) and GI tumors. Mechanosensitive ion channels could therefore provide a new perspective for the treatment of GI diseases. This review aims to highlight recent research advances regarding the function of mechanosensitive ion channels in the GI tract. Moreover, it outlines the potential role of mechanosensitive ion channels in related diseases, while describing the current understanding of interactions between the GI tract and mechanosensitive ion channels.
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Affiliation(s)
- Haoyu Yang
- Experimental Center of Basic Medicine, College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Chaofeng Hou
- Experimental Center of Basic Medicine, College of Basic Medical Sciences, Army Medical University, Chongqing, China
| | - Weidong Xiao
- Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Yuan Qiu
- Department of General Surgery, Xinqiao Hospital, Army Medical University, Chongqing, China
- *Correspondence: Yuan Qiu,
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9
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Modzelewska B, Drygalski K, Hady HR, Kiełczewska A, Chomentowski A, Koryciński K, Głuszyńska P, Kleszczewski T. Resveratrol Relaxes Human Gastric Smooth Muscles Through High Conductance Calcium-Activated Potassium Channel in a Nitric Oxide-independent Manner. Front Pharmacol 2022; 13:823887. [PMID: 35145416 PMCID: PMC8822120 DOI: 10.3389/fphar.2022.823887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 01/03/2022] [Indexed: 11/25/2022] Open
Abstract
Resveratrol, as a polyphenolic compound that can be isolated from plants, and also a component of red wine has broad beneficial pharmacological properties. The aim was to investigate the role of nitric oxide and potassium channels in resveratrol-induced relaxation of human gastric smooth muscle. Gastric tissues were obtained from patients who underwent sleeve gastrectomy for severe obesity (n = 10 aged 21–48; BMI 48.21 ± 1.14). The mechanical activity from the muscle strips was detected under isometric conditions as the response to increasing concentrations of resveratrol before and after different pharmacological treatments. Resveratrol caused an observable, dose-dependent gastric muscle relaxation. The maximal response caused by the highest concentration of resveratrol was 83.49 ± 2.85% (p < 0.0001) of the control. Preincubation with L-NNA, L-NAME, or ODQ did not prevent the resveratrol-induced relaxation. Apamin, glibenclamide, 4AP or tamoxifen, did not inhibit the relaxing effect of resveratrol, as well. In turn, blocking BKCa by TEA, iberiotoxin, or charybdotoxin resulted in inhibition of resveratrol-induced relaxation (91.08 ± 2.07, p < 0.05; 95.60 ± 1.52, p < 0.01 and 89.58 ± 1.98, p < 0.05, respectively). This study provides the first observation that the relaxant effects of resveratrol in human gastric muscle strips occur directly through BKCa channels and independently of nitric oxide signaling pathways. Furthermore, there is considerable potential for further extensive clinical studies with resveratrol as an effective new drug or health supplement to treat gastrointestinal dyspepsia and other gastric hypermotility disorders.
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Affiliation(s)
- Beata Modzelewska
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
- *Correspondence: Beata Modzelewska,
| | - Krzysztof Drygalski
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
- Clinical Research Center, Medical University of Bialystok, Bialystok, Poland
| | - Hady Razak Hady
- Clinical Department of General and Endocrine Surgery, Medical University of Bialystok, Bialystok, Poland
| | - Aleksandra Kiełczewska
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
| | - Andrzej Chomentowski
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
| | - Krzysztof Koryciński
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
| | - Paulina Głuszyńska
- Clinical Department of General and Endocrine Surgery, Medical University of Bialystok, Bialystok, Poland
| | - Tomasz Kleszczewski
- Department of Biophysics, Faculty of Medicine, Medical University of Bialystok, Bialystok, Poland
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10
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Uray IP, Uray K. Mechanotransduction at the Plasma Membrane-Cytoskeleton Interface. Int J Mol Sci 2021; 22:11566. [PMID: 34768998 PMCID: PMC8584042 DOI: 10.3390/ijms222111566] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 02/08/2023] Open
Abstract
Mechanical cues are crucial for survival, adaptation, and normal homeostasis in virtually every cell type. The transduction of mechanical messages into intracellular biochemical messages is termed mechanotransduction. While significant advances in biochemical signaling have been made in the last few decades, the role of mechanotransduction in physiological and pathological processes has been largely overlooked until recently. In this review, the role of interactions between the cytoskeleton and cell-cell/cell-matrix adhesions in transducing mechanical signals is discussed. In addition, mechanosensors that reside in the cell membrane and the transduction of mechanical signals to the nucleus are discussed. Finally, we describe two examples in which mechanotransduction plays a significant role in normal physiology and disease development. The first example is the role of mechanotransduction in the proliferation and metastasis of cancerous cells. In this system, the role of mechanotransduction in cellular processes, including proliferation, differentiation, and motility, is described. In the second example, the role of mechanotransduction in a mechanically active organ, the gastrointestinal tract, is described. In the gut, mechanotransduction contributes to normal physiology and the development of motility disorders.
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Affiliation(s)
- Iván P. Uray
- Department of Clinical Oncology, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary;
| | - Karen Uray
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
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11
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Kim HJ, La JH, Kim HM, Yang IS, Sung TS. Anti-diarrheal effect of Scutellaria baicalensis is associated with suppression of smooth muscle in the rat colon. Exp Ther Med 2019; 17:4748-4756. [PMID: 31105793 DOI: 10.3892/etm.2019.7469] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 03/19/2019] [Indexed: 12/13/2022] Open
Abstract
Scutellaria baicalensis (S. baicalensis) has been used to manage diarrhea, and its anti-inflammatory effects are responsible for anti-diarrheal effects. However, there are no data concerning its direct effect on colonic motility. Therefore, the effects of the major components of S. baicalensis (baicalin, baicalein and wogonin) on colonic motility were investigated. A segment of the distal colon of rats was placed in Krebs solution to monitor spontaneous giant contractions (GCs). Changes in GCs were recorded after applying baicalin, baicalein or wogonin. After pretreatment with Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME), 1H-(1,2,4)-oxadiazolo (4,2-a) quinoxalin-1-one (ODQ), tetradotoxin, w-conotoxin, apamin, and iberiotoxin, changes in GCs by wogonin were recorded and analyzed. The segment of the distal colon showed spontaneous GCs at a mean amplitude of 3.7±0.3 g with a frequency of 0.8±0.1/min. Baicalin, baicalein, and wogonin reduced both the amplitude and the frequency of GCs in a dose-dependent manner. Wogonin had the most potent inhibitory effect on GCs (IC50 was 14.6 µM in amplitude and 14.2 µM in frequency). Wogonin-induced GC reduction was not significantly affected by the inhibition of nitric oxide/cGMP pathways with L-NAME and ODQ. Blocking the enteric neurotransmission with tetradotoxin and ω-conotoxin was ineffective on the wogonin-induced reduction of GCs. Ca2+-activated K+ (KCa) channel blockers (apamin and iberiotoxin) significantly attenuated the inhibitory effects of wogonin on GCs (P<0.01). Wogonin was effective in inhibiting colonic motility, probably through the opening of KCa channels located in the smooth muscle apparatus. These findings suggest that wogonin may be a candidate drug for the management of dysmotility-related diarrhea.
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Affiliation(s)
- Hyun Ju Kim
- Department of Veterinary Physiology, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Jun-Ho La
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Hee Man Kim
- Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju 26426, Republic of Korea.,Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557-0357, USA
| | - Il-Suk Yang
- Department of Veterinary Physiology, College of Veterinary Medicine, Seoul National University, Seoul 08826, Republic of Korea
| | - Tae Sik Sung
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Reno, NV 89557-0357, USA
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12
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Xin F, Cheng Y, Ren J, Zhang S, Liu P, Zhao H, Huang H, Wang W. The extracellular loop of the auxiliary β1-subunit is involved in the regulation of BKCa channel mechanosensitivity. Am J Physiol Cell Physiol 2018; 315:C485-C493. [DOI: 10.1152/ajpcell.00037.2018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The large conductance Ca2+-activated potassium (BKCa) channel is activated by stretch. The stress-regulated exon (STREX) in α-subunits is known to affect the mechanosensitivity of BKCa channels. However, in human colonic smooth muscle cells (HCoSMCs), we found that the α-subunits without STREX (ZERO-BK) and β1-subunits could be detected yet the cells were mechanosensitive. Whether the β1-subunit is involved in the regulation of BKCa mechanosensitivity is unclear. In the present study, ZERO-BK and β1-subunits were individually expressed or coexpressed in HEK293 cells and cell-attached patch-clamp techniques were used to measure BKCa currents defining mechanosensitivity. Single-channel patch-clamp recordings from HEK293 cells cotransfected with ZERO-BK and β1-subunits showed stretch sensitivity, but there was no mechanosensitivity in HEK293 cells transfected only with ZERO-BK. We also showed that expression of the β1-subunit could increase mechanosensitivity of the STREX-type α-subunits (STREX-BK). To identify the domain in β1-subunits responsible for affecting stretch sensitivity, we expressed β1- LoopDel (chimeric β1-subunits without the extracellular loop) or β1- C TermDel (chimeric β1-subunits without COOH terminus) with ZERO-BK in HEK293 cells. The data showed that deletion of the extracellular loop but not the COOH terminus of β1-subunits virtually abolished the mechanosensitivity. These results suggest that the extracellular loop of the β1-subunit is involved in the regulation of BKCa channel mechanosensitivity and that role is independent of STREX.
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Affiliation(s)
- Fang Xin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
| | - Yuan Cheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
| | - Jie Ren
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
- Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, People’s Republic of China
| | - Sitao Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
| | - Ping Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
| | - Haiyan Zhao
- Yanjing Medical College, Capital Medical University, Beijing, People’s Republic of China
| | - Haixia Huang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
- Beijing Key Laboratory of Metabolic Disorders Related Cardiovascular Diseases, Capital Medical University, Beijing, People’s Republic of China
| | - Wei Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, People’s Republic of China
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13
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Xin F, Huang H, Liu P, Ren J, Zhang S, Cheng Y, Wang W. Inhibition of ZERO-BK by PKC is involved in carbachol-induced enhancement of rat colon smooth muscle motility. Neurogastroenterol Motil 2018; 30:e13312. [PMID: 29488290 DOI: 10.1111/nmo.13312] [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: 09/13/2017] [Accepted: 01/18/2018] [Indexed: 02/04/2023]
Abstract
BACKGROUND Muscarinic acetylcholine receptor (mAChR) activation is an important factor to enhance the motility of gastrointestinal (GI) smooth muscle. Large conductance Ca2+ -activated potassium (BK) channels are widely expressed in GI smooth muscle. Roles of BK in carbachol (a mAChR agonist) induced enhancement of GI motility and the molecular mechanisms remains unknown and were investigated in this study. METHODS Colonic smooth muscle (CSM) strip was perfused to record motility in vitro. The patch-clamp technique was used to record BK currents. RT-PCR was used to detect the expression of BK channels in rat CSM tissues. Two different types BK channels were constructed in HEK293 cells to investigate the regulation mechanism. Paired t tests were set with a P < .05 regarded as significant. KEY RESULTS Carbachol enhanced CSM contraction through M3 receptor (M3 R) were attenuated by IbTX, an inhibitor of BK. Carbachol inhibited BK currents in CSM cells and Go6983, an inhibitor of protein kinase C (PKC), reversed the effect. PKC activator, phorbol 12-myristate 13-acetate (PMA), inhibited BK currents. Two types of BK channels (ZERO-BK and STREX-BK) were detected in CSM. ZERO- but not STREX-BK channels expressed in HEK293 cells were inhibited by PMA. CONCLUSION Our results provide strong evidence that inhibition of ZERO-BK but not STREX-BK channels via PKC pathway is involved in the enhancement of CSM motility by mAChR activation. Besides the activation of BK by an increase in intracellular calcium, inhibition of BK played an important role in GI motility regulation during mAChR activation.
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Affiliation(s)
- F Xin
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - H Huang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - P Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - J Ren
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - S Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Y Cheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - W Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
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14
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Walewska A, Kulawiak B, Szewczyk A, Koprowski P. Mechanosensitivity of mitochondrial large-conductance calcium-activated potassium channels. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2018; 1859:797-805. [PMID: 29775559 DOI: 10.1016/j.bbabio.2018.05.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 04/29/2018] [Accepted: 05/10/2018] [Indexed: 12/01/2022]
Abstract
Potassium channels have been discovered in the inner mitochondrial membrane of various cells. These channels can regulate the mitochondrial membrane potential, the matrix volume, respiration and reactive species generation. Therefore, it is believed that their activation is cytoprotective in various tissues. In our study, the single-channel activity of a large-conductance calcium-activated potassium channel (mitoBKCa) was measured by the patch-clamp technique on mitoplasts derived from mitochondria isolated from human glioma U-87 MG cells. Here, we show for the first time that mechanical stimulation of mitoBKCa channels results in an increased probability of channel opening. However, the mechanosensitivity of mitoBKCa channels was variable with some channels exhibiting no mechanosensitivity. We detected the expression of mechanosensitive BKCa-STREX exon in U-87 MG cells and hypotesize, based on previous studies demonstrating the presence of multiple BKCa splice variants that variable mechanosensitivity of mitoBKCa could be the result of the presence of diverse BKCa isoforms in mitochondria of U-87 MG cells. Our findings indicate the possible involvement of the mitoBKCa channel in mitochondria activities in which changes in membrane tension and shape play a crucial role, such as fusion/fission and cristae remodeling.
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Affiliation(s)
- Agnieszka Walewska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Bogusz Kulawiak
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Adam Szewczyk
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland
| | - Piotr Koprowski
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology, 3 Pasteur St., 02-093 Warsaw, Poland.
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15
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Dopico AM, Bukiya AN, Jaggar JH. Calcium- and voltage-gated BK channels in vascular smooth muscle. Pflugers Arch 2018; 470:1271-1289. [PMID: 29748711 DOI: 10.1007/s00424-018-2151-y] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 04/27/2018] [Indexed: 02/04/2023]
Abstract
Ion channels in vascular smooth muscle regulate myogenic tone and vessel contractility. In particular, activation of calcium- and voltage-gated potassium channels of large conductance (BK channels) results in outward current that shifts the membrane potential toward more negative values, triggering a negative feed-back loop on depolarization-induced calcium influx and SM contraction. In this short review, we first present the molecular basis of vascular smooth muscle BK channels and the role of subunit composition and trafficking in the regulation of myogenic tone and vascular contractility. BK channel modulation by endogenous signaling molecules, and paracrine and endocrine mediators follows. Lastly, we describe the functional changes in smooth muscle BK channels that contribute to, or are triggered by, common physiological conditions and pathologies, including obesity, diabetes, and systemic hypertension.
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Affiliation(s)
- Alex M Dopico
- Department of Pharmacology, College of Medicine, The University of Tennessee Health Science Center, 71 South Manassas St., Memphis, TN, 38163, USA.
| | - Anna N Bukiya
- Department of Pharmacology, College of Medicine, The University of Tennessee Health Science Center, 71 South Manassas St., Memphis, TN, 38163, USA
| | - Jonathan H Jaggar
- Department of Physiology, College of Medicine, The University of Tennessee Health Science Center, Memphis, TN, USA
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16
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Melnyk MI, Dryn DO, Al Kury LT, Zholos AV, Soloviev AI. Liposomal quercetin potentiates maxi-K channel openings in smooth muscles and restores its activity after oxidative stress. J Liposome Res 2018; 29:94-101. [DOI: 10.1080/08982104.2018.1458864] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Mariia I. Melnyk
- Institute of Pharmacology and Toxicology, National Academy of Medical Science, Kyiv, Ukraine
- A.A. Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Dariia O. Dryn
- Institute of Pharmacology and Toxicology, National Academy of Medical Science, Kyiv, Ukraine
- A.A. Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Lina T. Al Kury
- Department of Health Sciences, Zayed University, Abu Dhabi, United Arab Emirates
| | - Alexander V. Zholos
- A.A. Bogomoletz Institute of Physiology, National Academy of Sciences of Ukraine, Kyiv, Ukraine
- ESC “Institute of Biology and Medicine”, Taras Shevchenko Kyiv National University, Kyiv, Ukraine
| | - Anatoly I. Soloviev
- Institute of Pharmacology and Toxicology, National Academy of Medical Science, Kyiv, Ukraine
- ESC “Institute of Biology and Medicine”, Taras Shevchenko Kyiv National University, Kyiv, Ukraine
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17
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Dai YC, Zheng L, Zhang YL, Chen X, Chen DL, Wang LJ, Tang ZP. Jianpi Qingchang decoction regulates intestinal motility of dextran sulfate sodium-induced colitis through reducing autophagy of interstitial cells of Cajal. World J Gastroenterol 2017; 23:4724-4734. [PMID: 28765693 PMCID: PMC5514637 DOI: 10.3748/wjg.v23.i26.4724] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 04/30/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate the underlying effect of Jianpi Qingchang decoction (JQD) regulating intestinal motility of dextran sulfate sodium (DSS)-induced colitis in mice.
METHODS C57BL/6 mice were randomly divided into four groups: the control group, the DSS group, the JQD group, and the 5-aminosalicylic acid group. Except for the control group, colitis was induced in other groups by giving distilled water containing 5% DSS. Seven days after modeling, the mice were administered corresponding drugs intragastrically. The mice were sacrificed on the 15th day. The disease activity index, macroscopic and histopathologic lesions, and ultrastructure of colon interstitial cells of Cajal (ICC) were observed. The levels of tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-10 and interferon gamma (IFN-γ), the expression of nuclear factor-kappa B (NF-κB) p65, c-kit, microtubule-associated protein 1 light chain 3 (LC3-II) and Beclin-l mRNA, and the colonic smooth muscle tension were assessed.
RESULTS Acute inflammation occurred in the mice administered DSS. Compared with the control group, the levels of IL-1β, TNF-α, IL-10 and IFN-γ, the expression of LC3-II, Beclin-1 and NF-κB p65 mRNA, and the contractile frequency increased (P < 0.05), the expression of c-kit mRNA and the colonic smooth muscle contractile amplitude decreased in the DSS group (P < 0.05). Compared with the DSS group, the levels of IL-10 and IFN-γ, the expression of c-kit mRNA, and the colonic smooth muscle contractile amplitude increased (P < 0.05), the levels of TNF-α and IL-1β, the expression of LC3-II, Beclin-1 and NF-κB p65 mRNA, and the contractile frequency decreased in the JQD group (P < 0.05).
CONCLUSION JQD can regulate the intestinal motility of DSS-induced colitis in mice through suppressing intestinal inflammatory cascade reaction, reducing autophagy of ICC, and regulating the network path of ICC/smooth muscle cells.
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Wang Y, Li JX, Ji GJ, Zhai K, Wang HH, Liu XG. The Involvement of Ca(2+) Signal Pathways in Distal Colonic Myocytes in a Rat Model of Dextran Sulfate Sodium-induced Colitis. Chin Med J (Engl) 2017; 129:1185-92. [PMID: 27174327 PMCID: PMC4878164 DOI: 10.4103/0366-6999.181968] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Background: Disrupted Ca2+ homeostasis contributes to the development of colonic dysmotility in ulcerative colitis (UC), but the underlying mechanisms are unknown. This study aimed to examine the alteration of colonic smooth muscle (SM) Ca2+ signaling and Ca2+ handling proteins in a rat model of dextran sulfate sodium (DSS)-induced UC. Methods: Male Sprague-Dawley rats were randomly divided into control (n = 18) and DSS (n = 17) groups. Acute colitis was induced by 5% DSS in the drinking water for 7 days. Contractility of colonic SM strips (controls, n = 8 and DSS, n = 7) was measured in an organ bath. Cytosolic resting Ca2+ levels (n = 3 in each group) and Ca2+ transients (n = 3 in each group) were measured in single colonic SM cells. Ca2+ handling protein expression was determined by Western blotting (n = 4 in each group). Differences between control and DSS groups were analyzed by a two-sample independent t-test. Results: Average tension and amplitude of spontaneous contractions of colonic muscle strips were significantly enhanced in DSS-treated rats compared with controls (1.25 ± 0.08 g vs. 0.96 ± 0.05 g, P = 0.007; and 2.67 ± 0.62 g vs. 0.52 ± 0.10 g, P = 0.013). Average tensions of carbachol-evoked contractions were much weaker in the DSS group (1.08 ± 0.10 g vs. 1.80 ± 0.19 g, P = 0.006). Spontaneous Ca2+ transients were observed in more SM cells from DSS-treated rats (15/30 cells) than from controls (5/36 cells). Peak caffeine-induced intracellular Ca2+ release was lower in SM cells of DSS-treated rats than controls (0.413 ± 0.046 vs. 0.548 ± 0.041, P = 0.033). Finally, several Ca2+ handling proteins in colonic SM were altered by DSS treatment, including sarcoplasmic reticulum calcium-transporting ATPase 2a downregulation and phospholamban and inositol 1,4,5-trisphosphate receptor 1 upregulation. Conclusions: Impaired intracellular Ca2+ signaling of colonic SM, caused by alteration of Ca2+ handing proteins, contribute to colonic dysmotility in DSS-induced UC.
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Affiliation(s)
- Yan Wang
- Department of Gastroenterology, Peking University First Hospital, Peking University, Beijing 100034, China
| | - Jun-Xia Li
- Department of Gastroenterology, Peking University First Hospital, Peking University, Beijing 100034, China
| | - Guang-Ju Ji
- Department of Biomacromolecules, National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Kui Zhai
- Department of Biomacromolecules, National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Hua-Hong Wang
- Department of Gastroenterology, Peking University First Hospital, Peking University, Beijing 100034, China
| | - Xin-Guang Liu
- Department of Gastroenterology, Peking University First Hospital, Peking University, Beijing 100034, China
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Alcaino C, Farrugia G, Beyder A. Mechanosensitive Piezo Channels in the Gastrointestinal Tract. CURRENT TOPICS IN MEMBRANES 2017; 79:219-244. [PMID: 28728818 PMCID: PMC5606247 DOI: 10.1016/bs.ctm.2016.11.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Sensation of mechanical forces is critical for normal function of the gastrointestinal (GI) tract and abnormalities in mechanosensation are linked to GI pathologies. In the GI tract there are several mechanosensitive cell types-epithelial enterochromaffin cells, intrinsic and extrinsic enteric neurons, smooth muscle cells and interstitial cells of Cajal. These cells use mechanosensitive ion channels that respond to mechanical forces by altering transmembrane ionic currents in a process called mechanoelectrical coupling. Several mechanosensitive ionic conductances have been identified in the mechanosensory GI cells, ranging from mechanosensitive voltage-gated sodium and calcium channels to the mechanogated ion channels, such as the two-pore domain potassium channels K2P (TREK-1) and nonselective cation channels from the transient receptor potential family. The recently discovered Piezo channels are increasingly recognized as significant contributors to cellular mechanosensitivity. Piezo1 and Piezo2 are nonselective cationic ion channels that are directly activated by mechanical forces and have well-defined biophysical and pharmacologic properties. The role of Piezo channels in the GI epithelium is currently under investigation and their role in the smooth muscle syncytium and enteric neurons is still not known. In this review, we outline the current state of knowledge on mechanosensitive ion channels in the GI tract, with a focus on the known and potential functions of the Piezo channels.
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Affiliation(s)
- C Alcaino
- Mayo Clinic College of Medicine, Rochester, MN, United States
| | - G Farrugia
- Mayo Clinic College of Medicine, Rochester, MN, United States
| | - A Beyder
- Mayo Clinic College of Medicine, Rochester, MN, United States
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20
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Role of BK Ca in Stretch-Induced Relaxation of Colonic Smooth Muscle. BIOMED RESEARCH INTERNATIONAL 2016; 2016:9497041. [PMID: 28018918 PMCID: PMC5149602 DOI: 10.1155/2016/9497041] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 09/30/2016] [Accepted: 10/23/2016] [Indexed: 12/15/2022]
Abstract
Stretch-induced relaxation has not been clearly identified in gastrointestinal tract. The present study is to explore the role of large conductance calcium-activated potassium channels (BKCa) in stretch-induced relaxation of colon. The expression and currents of BKCa were detected and the basal muscle tone and contraction amplitude of colonic smooth muscle strips were measured. The expression of BKCa in colon is higher than other GI segments (P < 0.05). The density of BKCa currents was very high in colonic smooth muscle cells (SMCs). BKCa in rat colonic SMCs were sensitive to stretch. The relaxation response of colonic SM strips to stretch was attenuated by charybdotoxin (ChTX), a nonspecific BKCa blocker (P < 0.05). After blocking enteric nervous activities by tetrodotoxin (TTX), the stretch-induced relaxation did not change (P > 0.05). Still, ChTX and iberiotoxin (IbTX, a specific BKCa blocker) attenuated the relaxation of the colonic muscle strips enduring stretch (P < 0.05). These results suggest stretch-activation of BKCa in SMCs was involved in the stretch-induced relaxation of colon. Our study highlights the role of mechanosensitive ion channels in SMCs in colon motility regulation and their physiological and pathophysiological significance is worth further study.
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21
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Ohya S, Kito H, Hatano N, Muraki K. Recent advances in therapeutic strategies that focus on the regulation of ion channel expression. Pharmacol Ther 2016; 160:11-43. [PMID: 26896566 DOI: 10.1016/j.pharmthera.2016.02.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A number of different ion channel types are involved in cell signaling networks, and homeostatic regulatory mechanisms contribute to the control of ion channel expression. Profiling of global gene expression using microarray technology has recently provided novel insights into the molecular mechanisms underlying the homeostatic and pathological control of ion channel expression. It has demonstrated that the dysregulation of ion channel expression is associated with the pathogenesis of neural, cardiovascular, and immune diseases as well as cancers. In addition to the transcriptional, translational, and post-translational regulation of ion channels, potentially important evidence on the mechanisms controlling ion channel expression has recently been accumulated. The regulation of alternative pre-mRNA splicing is therefore a novel therapeutic strategy for the treatment of dominant-negative splicing disorders. Epigenetic modification plays a key role in various pathological conditions through the regulation of pluripotency genes. Inhibitors of pre-mRNA splicing and histone deacetyalase/methyltransferase have potential as potent therapeutic drugs for cancers and autoimmune and inflammatory diseases. Moreover, membrane-anchoring proteins, lysosomal and proteasomal degradation-related molecules, auxiliary subunits, and pharmacological agents alter the protein folding, membrane trafficking, and post-translational modifications of ion channels, and are linked to expression-defect channelopathies. In this review, we focused on recent insights into the transcriptional, spliceosomal, epigenetic, and proteasomal regulation of ion channel expression: Ca(2+) channels (TRPC/TRPV/TRPM/TRPA/Orai), K(+) channels (voltage-gated, KV/Ca(2+)-activated, KCa/two-pore domain, K2P/inward-rectifier, Kir), and Ca(2+)-activated Cl(-) channels (TMEM16A/TMEM16B). Furthermore, this review highlights expression of these ion channels in expression-defect channelopathies.
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Affiliation(s)
- Susumu Ohya
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan.
| | - Hiroaki Kito
- Department of Pharmacology, Division of Pathological Sciences, Kyoto Pharmaceutical University, Kyoto 607-8414, Japan
| | - Noriyuki Hatano
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan
| | - Katsuhiko Muraki
- Laboratory of Cellular Pharmacology, School of Pharmacy, Aichi-Gakuin University, Nagoya 464-8650, Japan.
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22
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Currò D. The Modulation of Potassium Channels in the Smooth Muscle as a Therapeutic Strategy for Disorders of the Gastrointestinal Tract. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2016; 104:263-305. [PMID: 27038377 DOI: 10.1016/bs.apcsb.2015.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alterations of smooth muscle contractility contribute to the pathophysiology of important functional gastrointestinal disorders (FGIDs) such as functional dyspepsia and irritable bowel syndrome. Consequently, drugs that decrease smooth muscle contractility are effective treatments for these diseases. Smooth muscle contraction is mainly triggered by Ca(2+) influx through voltage-dependent channels located in the plasma membrane. Thus, the modulation of the membrane potential results in the regulation of Ca(2+) influx and cytosolic levels. K(+) channels play fundamental roles in these processes. The open probability of K(+) channels increases in response to various stimuli, including membrane depolarization (voltage-gated K(+) [K(V)] channels) and the increase in cytosolic Ca(2+) levels (Ca(2+)-dependent K(+) [K(Ca)] channels). K(+) channel activation is mostly associated with outward K(+) currents that hyperpolarize the membrane and reduce cell excitability and contractility. In addition, some K(+) channels are open at the resting membrane potential values of the smooth muscle cells in some gut segments and contribute to set the resting membrane potential itself. The closure of these channels induces membrane depolarization and smooth muscle contraction. K(V)1.2, 1.5, 2.2, 4.3, 7.4 and 11.1, K(Ca)1.1 and 2.3, and inwardly rectifying type 6K(+) (K(ir)6) channels play the most important functional roles in the gastrointestinal smooth muscle. Activators of all these channels may theoretically relax the gastrointestinal smooth muscle and could therefore be promising new therapeutic options for FGID. The challenge of future drug research and development in this area will be to synthesize molecules selective for the channel assemblies expressed in the gastrointestinal smooth muscle.
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Affiliation(s)
- Diego Currò
- Institute of Pharmacology, School of Medicine, Catholic University of the Sacred Heart, Rome, Italy.
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23
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Hermann A, Sitdikova GF, Weiger TM. Oxidative Stress and Maxi Calcium-Activated Potassium (BK) Channels. Biomolecules 2015; 5:1870-911. [PMID: 26287261 PMCID: PMC4598779 DOI: 10.3390/biom5031870] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/17/2015] [Accepted: 07/20/2015] [Indexed: 01/13/2023] Open
Abstract
All cells contain ion channels in their outer (plasma) and inner (organelle) membranes. Ion channels, similar to other proteins, are targets of oxidative impact, which modulates ion fluxes across membranes. Subsequently, these ion currents affect electrical excitability, such as action potential discharge (in neurons, muscle, and receptor cells), alteration of the membrane resting potential, synaptic transmission, hormone secretion, muscle contraction or coordination of the cell cycle. In this chapter we summarize effects of oxidative stress and redox mechanisms on some ion channels, in particular on maxi calcium-activated potassium (BK) channels which play an outstanding role in a plethora of physiological and pathophysiological functions in almost all cells and tissues. We first elaborate on some general features of ion channel structure and function and then summarize effects of oxidative alterations of ion channels and their functional consequences.
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Affiliation(s)
- Anton Hermann
- Department of Cell Biology, Division of Cellular and Molecular Neurobiology, University of Salzburg, Salzburg 5020, Austria.
| | - Guzel F Sitdikova
- Department of Physiology of Man and Animals, Kazan Federal University, Kazan 420008, Russia.
| | - Thomas M Weiger
- Department of Cell Biology, Division of Cellular and Molecular Neurobiology, University of Salzburg, Salzburg 5020, Austria.
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24
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Mazet B. Gastrointestinal motility and its enteric actors in mechanosensitivity: past and present. Pflugers Arch 2014; 467:191-200. [PMID: 25366494 DOI: 10.1007/s00424-014-1635-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 10/14/2014] [Accepted: 10/19/2014] [Indexed: 12/14/2022]
Abstract
Coordinated contractions of the smooth muscle layers of the gastrointestinal (GI) tract are required to produce motor patterns that ensure normal GI motility. The crucial role of the enteric nervous system (ENS), the intrinsic ganglionated network located within the GI wall, has long been recognized in the generation of the main motor patterns. However, devising an appropriate motility requires the integration of informations emanating from the lumen of the GI tract. As already found more than half a century ago, the ability of the GI tract to respond to mechanical forces such as stretch is not restricted to neuronal mechanisms. Instead, mechanosensitivity is now recognized as a property of several non-neuronal cell types, the excitability of which is probably involved in shaping the motor patterns. This brief review gives an overview on how mechanosensitivity of different cell types in the GI tract has been established and, whenever available, on what ionic conductances are involved in mechanotransduction and their potential impact on normal GI motility.
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Affiliation(s)
- Bruno Mazet
- Aix Marseille Université, CNRS, CRN2M UMR 7286, CS80011 Bd Pierre Dramard, 13344, Marseille Cedex 15, France,
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Waite SL, Gandhi SV, Khan RN, Chapman NR. The effect of trichostatin-A and tumor necrosis factor on expression of splice variants of the MaxiK and L-type channels in human myometrium. Front Physiol 2014; 5:261. [PMID: 25076912 PMCID: PMC4097961 DOI: 10.3389/fphys.2014.00261] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 06/20/2014] [Indexed: 01/30/2023] Open
Abstract
The onset of human parturition is associated with up-regulation of pro-inflammatory cytokines including tumor necrosis factor (TNF) as well as changes in ion flux, principally Ca2+ and K+, across the myometrial myocytes membrane. Elevation of intra-cellular Ca2+ from the sarcoplasmic reticulum opens L-type Ca2+ channels (LTCCs); in turn this increased calcium level activates MaxiK channels leading to relaxation. While the nature of how this cross-talk is governed remains unclear, our previous work demonstrated that the pro-inflammatory cytokine, TNF, and the histone deacetylase inhibitor, Trichostatin-A (TSA), exerted opposing effects on the expression of the pro-quiescent Gαs gene in human myometrial cells. Consequently, in this study we demonstrate that the different channel splice variants for both MaxiK and LTCC are expressed in primary myometrial myocytes. MaxiK mRNA expression was sensitive to TSA stimulation, this causing repression of the M1, M3, and M4 splice variants. A small but not statistically significantly increase in MaxiK expression was also seen in response to TNF. In contrast to this, expression of LTCC splice variants was seen to be influenced by both TNF and TSA. TNF induced overall increase in total LTCC expression while TSA stimulated a dual effect: causing induction of LTCC exon 8 expression but repressing expression of other LTCC splice variants including that encoding exons 30, 31, 33, and 34, exons 30–34 and exons 40–43. The significance of these observations is discussed herein.
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Affiliation(s)
- Sarah L Waite
- Academic Unit of Reproductive and Developmental Medicine, Department of Human Metabolism, University of Sheffield Sheffield, UK
| | - Saurabh V Gandhi
- Department of Obstetrics and Gynaecology, Sheffield Teaching Hospitals NHS Foundation Trust Sheffield, UK
| | - Raheela N Khan
- Division of Medical Sciences and Graduate Entry Medicine, School of Medicine, Royal Derby Hospital, University of Nottingham Derby, UK
| | - Neil R Chapman
- Academic Unit of Reproductive and Developmental Medicine, Department of Human Metabolism, University of Sheffield Sheffield, UK
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Hristov KL, Smith AC, Parajuli SP, Malysz J, Petkov GV. Large-conductance voltage- and Ca2+-activated K+ channel regulation by protein kinase C in guinea pig urinary bladder smooth muscle. Am J Physiol Cell Physiol 2013; 306:C460-70. [PMID: 24352333 DOI: 10.1152/ajpcell.00325.2013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Large-conductance voltage- and Ca(2+)-activated K(+) (BK) channels are critical regulators of detrusor smooth muscle (DSM) excitability and contractility. PKC modulates the contraction of DSM and BK channel activity in non-DSM cells; however, the cellular mechanism regulating the PKC-BK channel interaction in DSM remains unknown. We provide a novel mechanistic insight into BK channel regulation by PKC in DSM. We used patch-clamp electrophysiology, live-cell Ca(2+) imaging, and functional studies of DSM contractility to elucidate BK channel regulation by PKC at cellular and tissue levels. Voltage-clamp experiments showed that pharmacological activation of PKC with PMA inhibited the spontaneous transient BK currents in native freshly isolated guinea pig DSM cells. Current-clamp recordings revealed that PMA significantly depolarized DSM membrane potential and inhibited the spontaneous transient hyperpolarizations in DSM cells. The PMA inhibitory effects on DSM membrane potential were completely abolished by the selective BK channel inhibitor paxilline. Activation of PKC with PMA did not affect the amplitude of the voltage-step-induced whole cell steady-state BK current or the single BK channel open probability (recorded in cell-attached mode) upon inhibition of all major Ca(2+) sources for BK channel activation with thapsigargin, ryanodine, and nifedipine. PKC activation with PMA elevated intracellular Ca(2+) levels in DSM cells and increased spontaneous phasic and nerve-evoked contractions of DSM isolated strips. Our results support the concept that PKC activation leads to a reduction of BK channel activity in DSM via a Ca(2+)-dependent mechanism, thus increasing DSM contractility.
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Affiliation(s)
- Kiril L Hristov
- Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy, University of South Carolina, Columbia, South Carolina
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Takahashi K, Naruse K. Stretch-activated BK channel and heart function. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2013; 110:239-44. [PMID: 23281538 DOI: 10.1016/j.pbiomolbio.2012.08.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The heart is an organ that is exposed to extreme dynamic mechanical stimuli. From birth till death, the heart indefinitely repeats periodic contraction and dilation, i.e., shortening and elongation of cardiomyocytes. Mechanical stretch elicits a change in heart rate and may cause arrhythmia if it is excessive. Thus, mechanosensitivity is crucial to heart function. The molecule that is substantially involved in mechanosensitivity is a stretch-activated ion channel. Among several ion channels believed to be activated by stretch in the heart, the stretch-activated KCa (SAKCA) channel, a member of the group of large conductance (Big Potassium, BK) channels, shows a mechanosensitive (MS) response to membrane stretch. As BK channels respond to voltage and intracellular calcium concentration with large conductance, they are considered to be involved in repolarization after depolarization. Some BK channels are known to be activated by stretch and are expressed in a number of cells, including human osteoblasts and guinea pig intestinal neurons. The SAKCA channel was found to be sensitive to stretch in the chick heart. Given that the cardiomyocyte is unremittingly exposed to contraction and dilation and that it generates action potential and its contractility is modulated by intracellular calcium concentration, the SAKCA channel, which is dependent voltage and calcium, may be involved in action potential generation. It was recently reported that a BK channel is involved in the modulation of heart rate in the mouse. Further studies regarding the role of MS BK channels, including SAKCA, in the modulation of heart rate and contractility are expected.
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Affiliation(s)
- Ken Takahashi
- Department of Cardiovascular Physiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
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Huang H, Liang L, Liu P, Wei H, Sachs F, Niu W, Wang W. Mechanical effects on KATP channel gating in rat ventricular myocytes. PLoS One 2013; 8:e63337. [PMID: 23691027 PMCID: PMC3653899 DOI: 10.1371/journal.pone.0063337] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 04/02/2013] [Indexed: 11/18/2022] Open
Abstract
Cardiac KATP channels link metabolism with electrical activity. They are implicated in arrhythmias, secretion of atrial natriuretic peptide and protection of the heart from hypertrophy and failure. These processes may involve mechanosensitivity. KATP channels can be activated by mechanical stimulation and disrupting the cortical actin increases the activity. We propose that KATP channels are modulated by local bilayer tension and this tension is affected by cortical F-actin. Here we measured KATP background activity and stretch sensitivity with inside-out patches of rat ventricular myocytes before and after disrupting F-actin. Disrupting F-actin potentiated background activity but did not influence the slope sensitivity in the semilog relationship of NPo vs. suction that is a measure of the change in dimensions between closed and open states. Thus actin alters prestress on the channel probably by parallel elastic sharing of mean cortical tension with the bilayer.
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Affiliation(s)
- Haixia Huang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Lifang Liang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Ping Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Hua Wei
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Frederick Sachs
- Department of Physiology and Biophysics, SUNY, Buffalo, New York, United States of America
| | - Weizhen Niu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Wei Wang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
- * E-mail:
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Beyder A, Farrugia G. Targeting ion channels for the treatment of gastrointestinal motility disorders. Therap Adv Gastroenterol 2012; 5:5-21. [PMID: 22282704 PMCID: PMC3263980 DOI: 10.1177/1756283x11415892] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Gastrointestinal (GI) functional and motility disorders are highly prevalent and responsible for long-term morbidity and sometimes mortality in the affected patients. It is estimated that one in three persons has a GI functional or motility disorder. However, diagnosis and treatment of these widespread conditions remains challenging. This partly stems from the multisystem pathophysiology, including processing abnormalities in the central and peripheral (enteric) nervous systems and motor dysfunction in the GI wall. Interstitial cells of Cajal (ICCs) are central to the generation and propagation of the cyclical electrical activity and smooth muscle cells (SMCs) are responsible for electromechanical coupling. In these and other excitable cells voltage-sensitive ion channels (VSICs) are the main molecular units that generate and regulate electrical activity. Thus, VSICs are potential targets for intervention in GI motility disorders. Research in this area has flourished with advances in the experimental methods in molecular and structural biology and electrophysiology. However, our understanding of the molecular mechanisms responsible for the complex and variable electrical behavior of ICCs and SMCs remains incomplete. In this review, we focus on the slow waves and action potentials in ICCs and SMCs. We describe the constituent VSICs, which include voltage-gated sodium (Na(V)), calcium (Ca(V)), potassium (K(V), K(Ca)), chloride (Cl(-)) and nonselective ion channels (transient receptor potentials [TRPs]). VSICs have significant structural homology and common functional mechanisms. We outline the approaches and limitations and provide examples of targeting VSICs at the pores, voltage sensors and alternatively spliced sites. Rational drug design can come from an integrated view of the structure and mechanisms of gating and activation by voltage or mechanical stress.
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Affiliation(s)
- Arthur Beyder
- Enteric Neuroscience Program, Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN, USA
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