1
|
Peixoto-Neves D, Jaggar JH. Physiological functions and pathological involvement of ion channel trafficking in the vasculature. J Physiol 2024; 602:3275-3296. [PMID: 37818949 PMCID: PMC11006830 DOI: 10.1113/jp285007] [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: 08/09/2023] [Accepted: 09/28/2023] [Indexed: 10/13/2023] Open
Abstract
A variety of ion channels regulate membrane potential and calcium influx in arterial smooth muscle and endothelial cells to modify vascular functions, including contractility. The current (I) generated by a population of ion channels is equally dependent upon their number (N), open probability (Po) and single channel current (i), such that I = N.PO.i. A conventional view had been that ion channels traffic to the plasma membrane in a passive manner, resulting in a static surface population. It was also considered that channels assemble with auxiliary subunits prior to anterograde trafficking of the multimeric complex to the plasma membrane. Recent studies have demonstrated that physiological stimuli can regulate the surface abundance (N) of several different ion channels in arterial smooth muscle and endothelial cells to control arterial contractility. Physiological stimuli can also regulate the number of auxiliary subunits present in the plasma membrane to modify the biophysical properties, regulatory mechanisms and physiological functions of some ion channels. Furthermore, ion channel trafficking becomes dysfunctional in the vasculature during hypertension, which negatively impacts the regulation of contractility. The temporal kinetics of ion channel and auxiliary subunit trafficking can also vary depending on the signalling mechanisms and proteins involved. This review will summarize recent work that has uncovered the mechanisms, functions and pathological modifications of ion channel trafficking in arterial smooth muscle and endothelial cells.
Collapse
Affiliation(s)
| | - Jonathan H. Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis TN 38139
| |
Collapse
|
2
|
van der Horst J, Jepps TA. Proximity Labelling to Quantify Kv7.4 and Dynein Protein Interaction in Freshly Isolated Rat Vascular Smooth Muscle Cells. Bio Protoc 2024; 14:e4961. [PMID: 38841287 PMCID: PMC10958171 DOI: 10.21769/bioprotoc.4961] [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: 11/30/2023] [Revised: 02/07/2024] [Accepted: 02/07/2024] [Indexed: 06/07/2024] Open
Abstract
Understanding protein-protein interactions is crucial for unravelling subcellular protein distribution, contributing to our understanding of cellular organisation. Moreover, interaction studies can reveal insights into the mechanisms that cover protein trafficking within cells. Although various techniques such as Förster resonance energy transfer (FRET), co-immunoprecipitation, and fluorescence microscopy are commonly employed to detect protein interactions, their limitations have led to more advanced techniques such as the in situ proximity ligation assay (PLA) for spatial co-localisation analysis. The PLA technique, specifically employed in fixed cells and tissues, utilises species-specific secondary PLA probes linked to DNA oligonucleotides. When proteins are within 40 nm of each other, the DNA oligonucleotides on the probes interact, facilitating circular DNA formation through ligation. Rolling-circle amplification then produces DNA circles linked to the PLA probe. Fluorescently labelled oligonucleotides hybridise to the circles, generating detectable signals for precise co-localisation analysis. We employed PLA to examine the co-localisation of dynein with the Kv7.4 channel protein in isolated vascular smooth muscle cells from rat mesenteric arteries. This method enabled us to investigate whether Kv7.4 channels interact with dynein, thereby providing evidence of their retrograde transport by the microtubule network. Our findings illustrate that PLA is a valuable tool for studying potential novel protein interactions with dynein, and the quantifiable approach offers insights into whether these interactions are changed in disease.
Collapse
Affiliation(s)
- Jennifer van der Horst
- Vascular Biology Group, Department of Biomedical Sciences, University
of Copenhagen, Copenhagen, Denmark
| | - Thomas A. Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University
of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
3
|
Mozzicato AM, Bastrup JA, Sanchez-Alonso JL, van der Horst J, Gorelik J, Hägglund P, Jepps TA. Mesenteric artery smooth muscle cells from hypertensive rats have increased microtubule acetylation. Biochem J 2024; 481:387-403. [PMID: 38373073 DOI: 10.1042/bcj20230420] [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: 10/03/2023] [Revised: 02/19/2024] [Accepted: 02/19/2024] [Indexed: 02/21/2024]
Abstract
The dynamic nature of the microtubule network is dependent in part by post-translational modifications (PTMs) - particularly through acetylation, which stabilizes the microtubule network. Whether PTMs of the microtubule network in vascular smooth muscle cells (VSMCs) contribute to the pathophysiology of hypertension is unknown. The aim of this study was to determine the acetylated state of the microtubule network in the mesenteric arteries of spontaneously hypertensive rats (SHR). Experiments were performed on male normotensive rats and SHR mesenteric arteries. Western blotting and mass spectrometry determined changes in tubulin acetylation. Wire myography was used to investigate the effect of tubacin on isoprenaline-mediated vasorelaxations. Isolated cells from normotensive rats were used for scanning ion conductance microscopy (SICM). Mass spectrometry and Western blotting showed that tubulin acetylation is increased in the mesenteric arteries of the SHR compared with normotensive rats. Tubacin enhanced the β-adrenoceptor-mediated vasodilatation by isoprenaline when the endothelium was intact, but attenuated relaxations when the endothelium was denuded or nitric oxide production was inhibited. By pre-treating vessels with colchicine to disrupt the microtubule network, we were able to confirm that the effects of tubacin were microtubule-dependent. Using SICM, we examined the cell surface Young's modulus of VSMCs, but found no difference in control, tubacin-treated, or taxol-treated cells. Acetylation of tubulin at Lys40 is elevated in mesenteric arteries from the SHR. Furthermore, this study shows that tubacin has an endothelial-dependent bimodal effect on isoprenaline-mediated vasorelaxation.
Collapse
Affiliation(s)
- Anthony M Mozzicato
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Joakim A Bastrup
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Jose L Sanchez-Alonso
- Myocardial Function, National Heart and Lung Institute, Imperial College London, ICTEM, Hammersmith Hospital, London, U.K
| | - Jennifer van der Horst
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Julia Gorelik
- Myocardial Function, National Heart and Lung Institute, Imperial College London, ICTEM, Hammersmith Hospital, London, U.K
| | - Per Hägglund
- Protein Oxidation Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
4
|
Baldwin SN, Jepps TA, Greenwood IA. Cycling matters: Sex hormone regulation of vascular potassium channels. Channels (Austin) 2023; 17:2217637. [PMID: 37243715 PMCID: PMC10228406 DOI: 10.1080/19336950.2023.2217637] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 05/07/2023] [Accepted: 05/19/2023] [Indexed: 05/29/2023] Open
Abstract
Sex hormones and the reproductive cycle (estrus in rodents and menstrual in humans) have a known impact on arterial function. In spite of this, sex hormones and the estrus/menstrual cycle are often neglected experimental factors in vascular basic preclinical scientific research. Recent research by our own laboratory indicates that cyclical changes in serum concentrations of sex -hormones across the rat estrus cycle, primary estradiol, have significant consequences for the subcellular trafficking and function of KV. Vascular potassium channels, including KV, are essential components of vascular reactivity. Our study represents a small part of a growing field of literature aimed at determining the role of sex hormones in regulating arterial ion channel function. This review covers key findings describing the current understanding of sex hormone regulation of vascular potassium channels, with a focus on KV channels. Further, we highlight areas of research where the estrus cycle should be considered in future studies to determine the consequences of physiological oscillations in concentrations of sex hormones on vascular potassium channel function.
Collapse
Affiliation(s)
- Samuel N Baldwin
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Iain A Greenwood
- Vascular Biology Research Centre, Institute of Molecular and Clinical Sciences, St George’s University of London, London, UK
| |
Collapse
|
5
|
Valovič P, Behuliak M, Vaněčková I, Zicha J. Impaired vascular β-adrenergic relaxation in spontaneously hypertensive rats: The differences between conduit and resistance arteries. Eur J Pharmacol 2023; 958:176045. [PMID: 37708986 DOI: 10.1016/j.ejphar.2023.176045] [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: 04/19/2023] [Revised: 09/01/2023] [Accepted: 09/11/2023] [Indexed: 09/16/2023]
Abstract
It was suggested that impaired β-adrenergic relaxation in spontaneously hypertensive rats (SHR) might contribute to their high blood pressure (BP). Our study was focused on isoprenaline-induced dilatation of conduit femoral or resistance mesenteric arteries and on isoprenaline-induced BP reduction in SHR and Wistar-Kyoto rats (WKY). We confirmed decreased β-adrenergic relaxation of SHR femoral arteries due to the absence of its endothelium-independent component, whereas endothelium-dependent component of β-adrenergic smooth muscle relaxation was similar in both strains. Conversely, isoprenaline-induced relaxation of resistance mesenteric arteries was similar in both strains and this was true for endothelium-dependent and endothelium-independent components. We observed moderately reduced sensitivity of SHR mesenteric arteries to salmeterol (β2-adrenergic agonist) and this strain difference disappeared after endothelium removal. However, there was no difference in mesenteric arteries relaxation by dobutamine (β1-adrenergic agonist) which was independent of endothelium. The increasing isoprenaline doses elicited similar BP decrease in both rat strains, although BP sensitivity to isoprenaline was slightly decreased in SHR. The blockade of cyclooxygenase (indomethacin) and NO synthase (L-NAME) further reduced BP sensitivity to isoprenaline in SHR. On the other hand, salmeterol elicited similar BP decrease in both strains and the blockade of cyclooxygenase and NO synthase increased BP sensitivity to salmeterol in SHR as compared to WKY. In conclusion, attenuated β-adrenergic vasodilatation of conduit arteries of SHR but similar β-adrenergic relaxation of resistance mesenteric arteries from WKY and SHR and their similar BP response to β-adrenergic agonists do not support major role of altered β-adrenergic vasodilatation for high BP in genetic hypertension.
Collapse
Affiliation(s)
- Pavol Valovič
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Michal Behuliak
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Ivana Vaněčková
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic
| | - Josef Zicha
- Institute of Physiology, Czech Academy of Sciences, Prague, Czech Republic.
| |
Collapse
|
6
|
Manville RW, Baldwin SN, Eriksen EØ, Jepps TA, Abbott GW. Medicinal plant rosemary relaxes blood vessels by activating vascular smooth muscle KCNQ channels. FASEB J 2023; 37:e23125. [PMID: 37535015 PMCID: PMC10437472 DOI: 10.1096/fj.202301132r] [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: 06/07/2023] [Revised: 07/18/2023] [Accepted: 07/25/2023] [Indexed: 08/04/2023]
Abstract
The evergreen plant rosemary (Salvia rosmarinus) has been employed medicinally for centuries as a memory aid, analgesic, spasmolytic, vasorelaxant and antihypertensive, with recent preclinical and clinical evidence rationalizing some applications. Voltage-gated potassium (Kv) channels in the KCNQ (Kv7) subfamily are highly influential in the nervous system, muscle and epithelia. KCNQ4 and KCNQ5 regulate vascular smooth muscle excitability and contractility and are implicated as antihypertensive drug targets. Here, we found that rosemary extract potentiates homomeric and heteromeric KCNQ4 and KCNQ5 activity, resulting in membrane hyperpolarization. Two rosemary diterpenes, carnosol and carnosic acid, underlie the effects and, like rosemary, are efficacious KCNQ-dependent vasorelaxants, quantified by myography in rat mesenteric arteries. Sex- and estrous cycle stage-dependence of the vasorelaxation matches sex- and estrous cycle stage-dependent KCNQ expression. The results uncover a molecular mechanism underlying rosemary vasorelaxant effects and identify new chemical spaces for KCNQ-dependent vasorelaxants.
Collapse
Affiliation(s)
- Rían W. Manville
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Samuel N. Baldwin
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Emil Ørnberg Eriksen
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Thomas A. Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Geoffrey W. Abbott
- Bioelectricity Laboratory, Dept. of Physiology and Biophysics, School of Medicine, University of California, Irvine, CA, 92697, USA
| |
Collapse
|
7
|
Ehlers TS, van der Horst J, Møller S, Piil PK, Gliemann L, Aalkjaer C, Jepps TA, Hellsten Y. Colchicine enhances β adrenoceptor-mediated vasodilation in men with essential hypertension. Br J Clin Pharmacol 2023; 89:2179-2189. [PMID: 36764326 DOI: 10.1111/bcp.15688] [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: 09/21/2022] [Revised: 12/20/2022] [Accepted: 01/05/2023] [Indexed: 02/12/2023] Open
Abstract
AIMS The aim of this study is to examine whether colchicine improves β adrenoceptor-mediated vasodilation in humans by conducting a double-blinded, placebo-controlled intervention study. Colchicine treatment has known beneficial effects on cardiovascular health and reduces the incidence of cardiovascular disease. Studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor-mediated vasodilation, but this has not been determined in humans. METHODS Middle-aged men with essential hypertension were randomly assigned firstly to acute treatment with either 0.5 mg colchicine (n = 19) or placebo (n = 12). They were subsequently re-randomized for 3 weeks of treatment with either colchicine 0.5 mg twice daily (n = 16) or placebo (n = 15) followed by a washout period of 48-72 h. The vasodilator responses to isoprenaline, acetylcholine and sodium nitroprusside were determined as well as arterial pressure, arterial compliance and plasma inflammatory markers. RESULTS Acute colchicine treatment increased isoprenaline (by 38% for the highest dose) as well as sodium nitroprusside (by 29% main effect) -induced vasodilation but had no effect on the response to acetylcholine. The 3-week colchicine treatment followed by a washout period did not induce an accumulated or sustained effect on the β adrenoceptor response, and there was no effect on arterial pressure, arterial compliance or the level of measured inflammatory markers. CONCLUSION Colchicine acutely enhances β adrenoceptor- and nitric oxide-mediated changes in vascular conductance in humans, supporting that the mechanism previously demonstrated in rodents, translates to humans. The results provide novel translational evidence for a transient enhancing effect of colchicine on β adrenoceptor-mediated vasodilation in humans with essential hypertension. CONDENSED ABSTRACT Preclinical studies in isolated rodent arteries have shown that colchicine can enhance β adrenoceptor-mediated vasodilation. Here we show that this effect of colchicine can be translated to humans. Acute colchicine treatment was found to increase both isoprenaline- and sodium nitroprusside-induced vasodilation. The study provides the first translational evidence for a transient β adrenoceptor-mediated vasodilatory effect of colchicine in humans. The finding of an acute effect suggests that it may be clinically important to maintain an adequate bioavailability of colchicine.
Collapse
Affiliation(s)
- Thomas S Ehlers
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
| | - Jennifer van der Horst
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Sophie Møller
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
| | - Peter K Piil
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
| | - Lasse Gliemann
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
| | - Christian Aalkjaer
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Ylva Hellsten
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (Experimental Site), University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
8
|
Liu Y, Shuai K, Sun Y, Zhu L, Wu XM. Advances in the study of axon-associated vesicles. Front Mol Neurosci 2022; 15:1045778. [PMID: 36545123 PMCID: PMC9760877 DOI: 10.3389/fnmol.2022.1045778] [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: 09/16/2022] [Accepted: 11/17/2022] [Indexed: 12/12/2022] Open
Abstract
The central nervous system is the most important and difficult to study system in the human body and is known for its complex functions, components, and mechanisms. Neurons are the basic cellular units realizing neural functions. In neurons, vesicles are one of the critical pathways for intracellular material transport, linking information exchanges inside and outside cells. The axon is a vital part of neuron since electrical and molecular signals must be conducted through axons. Here, we describe and explore the formation, trafficking, and sorting of cellular vesicles within axons, as well as related-diseases and practical implications. Furthermore, with deepening of understanding and the development of new approaches, accumulating evidence proves that besides signal transmission between synapses, the material exchange and vesicular transmission between axons and extracellular environment are involved in physiological processes, and consequently to neural pathology. Recent studies have also paid attention to axonal vesicles and their physiological roles and pathological effects on axons themselves. Therefore, this review mainly focuses on these two key nodes to explain the role of intracellular vesicles and extracellular vesicles migrated from cells on axons and neurons, providing innovative strategy for future researches.
Collapse
Affiliation(s)
- Yanling Liu
- Institute of Special Environmental Medicine, Nantong University, Nantong, Jiangsu, China
| | - Ke Shuai
- Institute of Special Environmental Medicine, Nantong University, Nantong, Jiangsu, China
| | - Yiyan Sun
- Institute of Special Environmental Medicine, Nantong University, Nantong, Jiangsu, China
| | - Li Zhu
- Institute of Special Environmental Medicine, Nantong University, Nantong, Jiangsu, China,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Xiao-Mei Wu
- Institute of Special Environmental Medicine, Nantong University, Nantong, Jiangsu, China,Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China,*Correspondence: Xiao-Mei Wu,
| |
Collapse
|
9
|
van der Horst J, Rognant S, Hellsten Y, Aalkjær C, Jepps TA. Dynein Coordinates β2-Adrenoceptor-Mediated Relaxation in Normotensive and Hypertensive Rat Mesenteric Arteries. Hypertension 2022; 79:2214-2227. [PMID: 35929419 DOI: 10.1161/hypertensionaha.122.19351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The voltage-gated potassium channel (Kv)7.4 and Kv7.5 channels contribute to the β-adrenoceptor-mediated vasodilatation. In arteries from hypertensive rodents, the Kv7.4 channel is downregulated and function attenuated, which contributes to the reduced β-adrenoceptor-mediated vasodilatation observed in these arteries. Recently, we showed that disruption of the microtubule network, with colchicine, or inhibition of the microtubule motor protein, dynein, with ciliobrevin D, enhanced the membrane abundance and function of Kv7.4 channels in rat mesenteric arteries. This study aimed to determine whether these pharmacological compounds can improve Kv7.4 function in third-order mesenteric arteries from the spontaneously hypertensive rat, thereby restoring the β-adrenoceptor-mediated vasodilatation. METHODS Wire and intravital myography was performed on normotensive and hypertensive male rat mesenteric arteries and immunostaining was performed on isolated smooth muscle cells from the same arteries. RESULTS Using wire and intravital microscopy, we show that ciliobrevin D enhanced the β-adrenoceptor-mediated vasodilatation by isoprenaline. This effect was inhibited partially by the Kv7 channel blocker linopirdine and was dependent on an increased functional contribution of the β2-adrenoceptor to the isoprenaline-mediated relaxation. In mesenteric arteries from the spontaneously hypertensive rat, ciliobrevin D and colchicine both improved the isoprenaline-mediated vasorelaxation and relaxation to the Kv7.2 -7.5 activator, ML213. Immunostaining confirmed ciliobrevin D enhanced the membrane abundance of Kv7.4. As well as an increase in the function of Kv7.4, the functional changes were associated with an increase in the contribution of β2-adrenoceptor following isoprenaline treatment. Immunostaining experiments showed ciliobrevin D prevented isoprenaline-mediated internalizationof the β2-adrenoceptor. CONCLUSIONS Overall, these data show that colchicine and ciliobrevin D can induce a β2-adrenoceptor-mediated vasodilatation in arteries from the spontaneously hypertensive rat as well as reinstating Kv7.4 channel function.
Collapse
Affiliation(s)
- Jennifer van der Horst
- Department of Biomedical Sciences (J.v.d.H., S.R., C.A., T.A.J.), University of Copenhagen, Denmark.,The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (J.v.d.H., Y.H.), University of Copenhagen, Denmark
| | - Salomé Rognant
- Department of Biomedical Sciences (J.v.d.H., S.R., C.A., T.A.J.), University of Copenhagen, Denmark
| | - Ylva Hellsten
- The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports (J.v.d.H., Y.H.), University of Copenhagen, Denmark
| | - Christian Aalkjær
- Department of Biomedical Sciences (J.v.d.H., S.R., C.A., T.A.J.), University of Copenhagen, Denmark.,Department of Biomedicine, Aarhus University, Denmark (C.A.)
| | - Thomas A Jepps
- Department of Biomedical Sciences (J.v.d.H., S.R., C.A., T.A.J.), University of Copenhagen, Denmark
| |
Collapse
|
10
|
Rognant S, Kravtsova VV, Bouzinova EV, Melnikova EV, Krivoi II, Pierre SV, Aalkjaer C, Jepps TA, Matchkov VV. The microtubule network enables Src kinase interaction with the Na,K-ATPase to generate Ca2+ flashes in smooth muscle cells. Front Physiol 2022; 13:1007340. [PMID: 36213229 PMCID: PMC9538378 DOI: 10.3389/fphys.2022.1007340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 09/05/2022] [Indexed: 12/03/2022] Open
Abstract
Background: Several local Ca2+ events are characterized in smooth muscle cells. We have previously shown that an inhibitor of the Na,K-ATPase, ouabain induces spatially restricted intracellular Ca2+ transients near the plasma membrane, and suggested the importance of this signaling for regulation of intercellular coupling and smooth muscle cell contraction. The mechanism behind these Na,K-ATPase-dependent “Ca2+ flashes” remains to be elucidated. In addition to its conventional ion transport function, the Na,K-ATPase is proposed to contribute to intracellular pathways, including Src kinase activation. The microtubule network is important for intracellular signaling, but its role in the Na,K-ATPase-Src kinase interaction is not known. We hypothesized the microtubule network was responsible for maintaining the Na,K-ATPase-Src kinase interaction, which enables Ca2+ flashes. Methods: We characterized Ca2+ flashes in cultured smooth muscle cells, A7r5, and freshly isolated smooth muscle cells from rat mesenteric artery. Cells were loaded with Ca2+-sensitive fluorescent dyes, Calcium Green-1/AM and Fura Red/AM, for ratiometric measurements of intracellular Ca2+. The Na,K-ATPase α2 isoform was knocked down with siRNA and the microtubule network was disrupted with nocodazole. An involvement of the Src signaling was tested pharmacologically and with Western blot. Protein interactions were validated with proximity ligation assays. Results: The Ca2+ flashes were induced by micromolar concentrations of ouabain. Knockdown of the α2 isoform Na,K-ATPase abolished Ca2+ flashes, as did inhibition of tyrosine phosphorylation with genistein and PP2, and the inhibitor of the Na,K-ATPase-dependent Src activation, pNaKtide. Ouabain-induced Ca2+ flashes were associated with Src kinase activation by phosphorylation. The α2 isoform Na,K-ATPase and Src kinase colocalized in the cells. Disruption of microtubule with nocodazole inhibited Ca2+ flashes, reduced Na,K-ATPase/Src interaction and Src activation. Conclusion: We demonstrate that the Na,K-ATPase-dependent Ca2+ flashes in smooth muscle cells require an interaction between the α2 isoform Na, K-ATPase and Src kinase, which is maintained by the microtubule network.
Collapse
Affiliation(s)
- Salomé Rognant
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Violetta V. Kravtsova
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | | | | | - Igor I. Krivoi
- Department of General Physiology, St. Petersburg State University, St. Petersburg, Russia
| | - Sandrine V. Pierre
- Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV, United States
| | | | - Thomas A. Jepps
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Vladimir V. Matchkov
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- *Correspondence: Vladimir V. Matchkov,
| |
Collapse
|
11
|
Bastrup JA, Aalkjær C, Jepps TA. Identification of novel proteins and mechanistic pathways associated with early-onset hypertension by deep proteomic mapping of resistance arteries. J Biol Chem 2021; 298:101512. [PMID: 34929167 PMCID: PMC8760518 DOI: 10.1016/j.jbc.2021.101512] [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: 08/08/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 12/17/2022] Open
Abstract
Resistance arteries are small blood vessels that create resistance to blood flow. In hypertension, resistance arteries undergo remodeling, affecting their ability to contract and relax appropriately. To date, no study has mapped the hypertension-related proteomic changes in resistance arteries. Using a novel data-independent acquisition–mass spectrometry (DIA-MS) approach, we determined the proteomic changes in small mesenteric and renal arteries in pre- and early-onset hypertension from the spontaneously hypertensive rat (SHR) model, which represents human primary hypertension. Compared with normotensive controls, mesenteric arteries from 12-week-old SHRs had 286 proteins that were significantly up- or downregulated, whereas 52 proteins were identified as up- or downregulated in mesenteric arteries from 6-week-old SHRs. Of these proteins, 18 were also similarly regulated in SHR renal arteries. Our pathway analyses reveal several novel pathways in the pathogenesis of hypertension. Finally, using a matrisome database, we identified 38 altered extracellular-matrix-associated proteins, many of which have never previously been associated with hypertension. Taken together, this study reveals novel proteins and mechanisms that are associated with early-onset hypertension, thereby providing novel insights into disease progression.
Collapse
Affiliation(s)
- Joakim A Bastrup
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Denmark
| | - Christian Aalkjær
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Denmark; Department of Biomedicine, Aarhus University, Denmark
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Denmark.
| |
Collapse
|
12
|
Jepps TA. Kv7 channel trafficking by the microtubule network in vascular smooth muscle. Acta Physiol (Oxf) 2021; 232:e13692. [PMID: 34021973 PMCID: PMC8365713 DOI: 10.1111/apha.13692] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 05/17/2021] [Accepted: 05/19/2021] [Indexed: 12/17/2022]
Abstract
In arterial smooth muscle cells, changes in availability of integral membrane proteins influence the regulation of blood flow and blood pressure, which is critical for human health. However, the mechanisms that coordinate the trafficking and membrane expression of specific receptors and ion channels in vascular smooth muscle are poorly understood. In the vasculature, very little is known about microtubules, which form a road network upon which proteins can be transported to and from the cell membrane. This review article summarizes the impact of the microtubule network on arterial contractility, highlighting the importance of the network, with an emphasis on our recent findings regarding the trafficking of the voltage‐dependent Kv7 channels.
Collapse
Affiliation(s)
- Thomas A Jepps
- Vascular Biology Group Department of Biomedical Sciences University of Copenhagen Blegdamsvej 3 2200 Copenhagen N Denmark
| |
Collapse
|
13
|
Moss RL, Cremo C, Granzier HL. Toward an understanding of myofibrillar function in health and disease. J Gen Physiol 2021; 153:211822. [PMID: 33620422 PMCID: PMC7905996 DOI: 10.1085/jgp.202112880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Richard L Moss
- Cardiovascular Research Center, Department of Cell and Regenerative Biology, School of Medicine and Public Health, University of Wisconsin, Madison, WI
| | - Christine Cremo
- Department of Pharmacology, School of Medicine, University of Nevada, Reno, Reno, NV
| | - Henk L Granzier
- Cellular and Molecular Medicine, University of Arizona, Tucson, AZ
| |
Collapse
|