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Talbot BE, Vandorpe DH, Stotter BR, Alper SL, Schlondorff JS. Transmembrane insertases and N-glycosylation critically determine synthesis, trafficking, and activity of the nonselective cation channel TRPC6. J Biol Chem 2019; 294:12655-12669. [PMID: 31266804 PMCID: PMC6709635 DOI: 10.1074/jbc.ra119.008299] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/28/2019] [Indexed: 12/12/2022] Open
Abstract
Transient receptor potential cation channel subfamily C member 6 (TRPC6) is a widely expressed ion channel. Gain-of-function mutations in the human TRPC6 channel cause autosomal-dominant focal segmental glomerulosclerosis, but the molecular components involved in disease development remain unclear. Here, we found that overexpression of gain-of-function TRPC6 channel variants is cytotoxic in cultured cells. Exploiting this phenotype in a genome-wide CRISPR/Cas screen for genes whose inactivation rescues cells from TRPC6-associated cytotoxicity, we identified several proteins essential for TRPC6 protein expression, including the endoplasmic reticulum (ER) membrane protein complex transmembrane insertase. We also identified transmembrane protein 208 (TMEM208), a putative component of a signal recognition particle-independent (SND) ER protein-targeting pathway, as being necessary for expression of TRPC6 and several other ion channels and transporters. TRPC6 expression was also diminished by loss of the previously uncharacterized WD repeat domain 83 opposite strand (WDR83OS), which interacted with both TRPC6 and TMEM208. Additionally enriched among the screen hits were genes involved in N-linked protein glycosylation. Deletion of the mannosyl (α-1,3-)-glycoprotein β-1,2-N-acetylglucosaminyltransferase (MGAT1), necessary for the generation of complex N-linked glycans, abrogated TRPC6 gain-of-function variant-mediated Ca2+ influx and extracellular signal-regulated kinase activation in HEK cells, but failed to diminish cytotoxicity in cultured podocytes. However, mutating the two TRPC6 N-glycosylation sites abrogated the cytotoxicity of mutant TRPC6 and reduced its surface expression. These results expand the targets of TMEM208-mediated ER translocation to include multipass transmembrane proteins and suggest that TRPC6 N-glycosylation plays multiple roles in modulating channel trafficking and activity.
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Affiliation(s)
- Brianna E Talbot
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - David H Vandorpe
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Brian R Stotter
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
- Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115
| | - Seth L Alper
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
| | - Johannes S Schlondorff
- Division of Nephrology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
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Staehr C, Hangaard L, Bouzinova EV, Kim S, Rajanathan R, Boegh Jessen P, Luque N, Xie Z, Lykke-Hartmann K, Sandow SL, Aalkjaer C, Matchkov VV. Smooth muscle Ca 2+ sensitization causes hypercontractility of middle cerebral arteries in mice bearing the familial hemiplegic migraine type 2 associated mutation. J Cereb Blood Flow Metab 2019; 39. [PMID: 29513112 PMCID: PMC6681533 DOI: 10.1177/0271678x18761712] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Familial hemiplegic migraine type 2 (FHM2) is associated with inherited point-mutations in the Na,K-ATPase α2 isoform, including G301R mutation. We hypothesized that this mutation affects specific aspects of vascular function, and thus compared cerebral and systemic arteries from heterozygote mice bearing the G301R mutation (Atp1a2+/-G301R) with wild type (WT). Middle cerebral (MCA) and mesenteric small artery (MSA) function was compared in an isometric myograph. Cerebral blood flow was assessed with Laser speckle analysis. Intracellular Ca2+ and membrane potential were measured simultaneously. Protein expression was semi-quantified by immunohistochemistry. Protein phosphorylation was analysed by Western blot. MSA from Atp1a2+/-G301R and WT showed similar contractile responses. The Atp1a2+/-G301R MCA constricted stronger to U46619, endothelin and potassium compared to WT. This was associated with an increased depolarization, although the Ca2+ change was smaller than in WT. The enhanced constriction of Atp1a2+/-G301R MCA was associated with increased cSrc activation, stronger sensitization to [Ca2+]i and increased MYPT1 phosphorylation. These differences were abolished by cSrc inhibition. Atp1a2+/-G301R mice had reduced resting blood flow through MCA in comparison with WT mice. FHM2-associated mutation leads to elevated contractility of MCA due to sensitization of the contractile machinery to Ca2+, which is mediated via Na,K-ATPase/Src-kinase/MYPT1 signalling.
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Affiliation(s)
| | - Lise Hangaard
- 1 Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | - Sukhan Kim
- 1 Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | | | | | - Nathan Luque
- 2 Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Queensland, Australia
| | - Zijian Xie
- 3 Marshall Institute for Interdisciplinary Research, Marshall University, Huntington, WV, USA
| | | | - Shaun L Sandow
- 2 Faculty of Science, Health, Education and Engineering, University of the Sunshine Coast, Queensland, Australia
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53
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Canales J, Morales D, Blanco C, Rivas J, Díaz N, Angelopoulos I, Cerda O. A TR(i)P to Cell Migration: New Roles of TRP Channels in Mechanotransduction and Cancer. Front Physiol 2019; 10:757. [PMID: 31275168 PMCID: PMC6591513 DOI: 10.3389/fphys.2019.00757] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 05/31/2019] [Indexed: 12/20/2022] Open
Abstract
Cell migration is a key process in cancer metastasis, allowing malignant cells to spread from the primary tumor to distant organs. At the molecular level, migration is the result of several coordinated events involving mechanical forces and cellular signaling, where the second messenger Ca2+ plays a pivotal role. Therefore, elucidating the regulation of intracellular Ca2+ levels is key for a complete understanding of the mechanisms controlling cellular migration. In this regard, understanding the function of Transient Receptor Potential (TRP) channels, which are fundamental determinants of Ca2+ signaling, is critical to uncovering mechanisms of mechanotransduction during cell migration and, consequently, in pathologies closely linked to it, such as cancer. Here, we review recent studies on the association between TRP channels and migration-related mechanotransduction events, as well as in the involvement of TRP channels in the migration-dependent pathophysiological process of metastasis.
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Affiliation(s)
- Jimena Canales
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - Diego Morales
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - Constanza Blanco
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - José Rivas
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - Nicolás Díaz
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - Ioannis Angelopoulos
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile
| | - Oscar Cerda
- Program of Cellular and Molecular Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile.,Millennium Nucleus of Ion Channels-Associated Diseases, Santiago, Chile.,The Wound Repair, Treatment and Health (WoRTH) Initiative, Santiago, Chile
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Yin MZ, Kim HJ, Suh EY, Zhang YH, Yoo HY, Kim SJ. Endurance exercise training restores atrophy-induced decreases of myogenic response and ionic currents in rat skeletal muscle artery. J Appl Physiol (1985) 2019; 126:1713-1724. [DOI: 10.1152/japplphysiol.00962.2018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Atrophic limbs exhibit decreased blood flow and histological changes in the arteries perfusing muscles. However, the effect of atrophy on vascular smooth muscle function is poorly understood. Here, we investigated the effect of unilateral sciatic denervation on the myogenic response (MR) and the ionic currents in deep femoral artery (DFA) smooth muscles from Sprague-Dawley rats. Because denervated rats were capable of treadmill exercise (20 m/min, 30 min, 3 times/wk), the impact of exercise training on these effects was also assessed. Skeletal arteries were harvested 3 or 5 wk after surgery. Then skeletal arteries or myocytes were subjected to video analysis of pressurized artery, myography, whole-cell patch clamp, and real-time quantitative PCR to determine the effect of hindlimb paralysis in the presence/absence of exercise training on MR, contractility, ionic currents, and channel transcription, respectively. In sedentary rats, atrophy was associated with loss of MR in the DFA at 5 wk. The contralateral DFA had a normal MR. At 5 wk after surgery, DFA myocytes from the atrophic limbs exhibited depressed L-type Ca2+currents, GTPγS-induced transient receptor potential cation channel (TRPC)-like currents, 80 mM KCl-induced vasoconstriction, TRPC6 mRNA, and voltage-gated K+and inwardly rectifying K+currents. Exercise training abrogated the differences in all of these functions between atrophic side and contralateral side DFA myocytes. These results suggest that a probable increase in hemodynamic stimuli in skeletal artery smooth muscle plays an important role in maintaining MR and ionic currents in skeletal artery smooth muscle. This may also explain the observed benefits of exercise in patients with limb paralysis.NEW & NOTEWORTHY Myogenic responses (MRs) in rat skeletal arteries feeding the unilateral atrophic hindlimb were impaired. In addition, the L-type Ca2+channel current, the TRPC6-like current, and TRPC6 mRNA levels in the corresponding myocytes decreased. Voltage-gated K+channel currents and inwardly rectifying K+channel currents were also attenuated in atrophic side myocytes. Exercise training effectively abrogated electrophysiological dysfunction of atrophic side myocytes and prevented loss of the MR.
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Affiliation(s)
- Ming Zhe Yin
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hae Jin Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Eun Yeong Suh
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Yin Hua Zhang
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hae Young Yoo
- Chung-Ang University Red Cross College of Nursing, Seoul, Republic of Korea
| | - Sung Joon Kim
- Department of Physiology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
- Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
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TRPC6 inactivation does not affect loss of renal function in nephrotoxic serum glomerulonephritis in rats, but reduces severity of glomerular lesions. Biochem Biophys Rep 2019; 17:139-150. [PMID: 30662960 PMCID: PMC6325086 DOI: 10.1016/j.bbrep.2018.12.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 12/06/2018] [Accepted: 12/16/2018] [Indexed: 12/26/2022] Open
Abstract
Canonical transient receptor potential-6 (TRPC6) channels have been implicated in a variety of chronic kidney diseases including familial and acquired forms of focal and segmental glomerulosclerosis (FSGS) and renal fibrosis following ureteral obstruction. Here we have examined the role of TRPC6 in progression of inflammation and fibrosis in the nephrotoxic serum (NTS) model of crescentic glomerulonephritis. This was assessed in rats with non-functional TRPC6 channels due to genomic disruption of an essential domain in TRPC6 channels (Trpc6del/del rats) and wild-type littermates (Trpc6wt/wt rats). Administration of NTS evoked albuminuria and proteinuria observed 4 and 28 days later that was equally severe in Trpc6wt/wt and Trpc6del/del rats. By 28 days, there were dense deposits of complement and IgG within glomeruli in both genotypes, accompanied by severe inflammation and fibrosis readily observed by standard histological methods, and also by increases in renal cortical expression of multiple markers (α-smooth muscle actin, vimentin, NLRP3, and CD68). Tubulointerstitial fibrosis appeared equally severe in Trpc6wt/wt and Trpc6del/del rats. TRPC6 inactivation did not protect against the substantial declines in renal function (increases in blood urea nitrogen, serum creatinine and kidney:body weight ratio) in NTS-treated animals, and increases in a urine maker of proximal tubule pathology (β2-macroglobulin) were actually more severe in Trpc6del/del animals. By contrast, glomerular pathology, blindly scored from histology, and from renal cortical expression of podocin suggested a partial but significant protective effect of TRPC6 inactivation within the glomerular compartment, at least during the autologous phase of the NTS model. TRPC6 inactivation in rats does not affect declines in overall renal function in an autoimmune model of rapidly progressing glomerulonephritis. TRPC6 inactivation does not reduce renal fibrosis or tubulointerstitial disease in autoimmune glomerulonephritis, and may exacerbate proximal tubule dysfunction in this model. TRPC6 inactivation reduces glomerulosclerosis and podocyte loss in autoimmune glomerulonephritis in rats.
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Key Words
- BUN, blood urea nitrogen
- CKD, chronic kidney disease
- Chronic kidney disease
- FSGS, focal and segmental glomerulosclerosis
- GBM, glomerular basement membrane
- Glomerulonephritis
- IL-1β, interleukin 1β
- NLRP3, NOD-like receptor pyrin domain containing-3 protein
- NTS, nephrotoxic serum
- PAN, puromycin amino nucleoside
- PAS, periodic acid-Schiff’s stain
- Renal fibrosis
- SMA, α-smooth muscle actin
- TCA, trichloroacetic acid
- TNF, tumor necrosis factor
- TRPC3, canonical transient receptor potential-3 channel
- TRPC5, canonical transient receptor potential-5 channel
- TRPC6
- TRPC6, canonical transient receptor potential-6 channel
- UUO, unilateral ureteral obstruction
- suPAR, soluble urokinase receptor
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Cellular and Ionic Mechanisms of Arterial Vasomotion. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1124:297-312. [DOI: 10.1007/978-981-13-5895-1_12] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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57
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Carnevale D, Facchinello N, Iodice D, Bizzotto D, Perrotta M, De Stefani D, Pallante F, Carnevale L, Ricciardi F, Cifelli G, Da Ros F, Casaburo M, Fardella S, Bonaldo P, Innocenzi G, Rizzuto R, Braghetta P, Lembo G, Bressan GM. Loss of EMILIN-1 Enhances Arteriolar Myogenic Tone Through TGF-β (Transforming Growth Factor-β)–Dependent Transactivation of EGFR (Epidermal Growth Factor Receptor) and Is Relevant for Hypertension in Mice and Humans. Arterioscler Thromb Vasc Biol 2018; 38:2484-2497. [DOI: 10.1161/atvbaha.118.311115] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Daniela Carnevale
- From the Department of Molecular Medicine, Sapienza University of Rome, Italy (D.C., M.P., G.L.)
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Nicola Facchinello
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
| | - Daniele Iodice
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Dario Bizzotto
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
| | - Marialuisa Perrotta
- From the Department of Molecular Medicine, Sapienza University of Rome, Italy (D.C., M.P., G.L.)
| | - Diego De Stefani
- Department of Biomedical Sciences (D.D.S., R.R.), University of Padova, Italy
| | - Fabio Pallante
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Lorenzo Carnevale
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Franco Ricciardi
- Department of Neurosurgery (F.R., G.I.), IRCCS Neuromed, Pozzilli, Italy
| | - Giuseppe Cifelli
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Francesco Da Ros
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
| | - Manuel Casaburo
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Stefania Fardella
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Paolo Bonaldo
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
| | | | - Rosario Rizzuto
- Department of Biomedical Sciences (D.D.S., R.R.), University of Padova, Italy
| | - Paola Braghetta
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
| | - Giuseppe Lembo
- From the Department of Molecular Medicine, Sapienza University of Rome, Italy (D.C., M.P., G.L.)
- Department of Angiocardioneurology and Translational Medicine (D.C., D.I., F.P., L.C., G.C., M.C., S.F., G.L.), IRCCS Neuromed, Pozzilli, Italy
| | - Giorgio M. Bressan
- Department of Molecular Medicine (N.F., D.B., F.D.R., P. Bonaldo, P. Braghetta, G.M.B.), University of Padova, Italy
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Björling K, Joseph PD, Egebjerg K, Salomonsson M, Hansen JL, Ludvigsen TP, Jensen LJ. Role of age, Rho-kinase 2 expression, and G protein-mediated signaling in the myogenic response in mouse small mesenteric arteries. Physiol Rep 2018; 6:e13863. [PMID: 30198176 PMCID: PMC6129776 DOI: 10.14814/phy2.13863] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 08/21/2018] [Indexed: 12/16/2022] Open
Abstract
The myogenic response (MR) and myogenic tone (MT) in resistance vessels is crucial for maintaining peripheral vascular resistance and blood flow autoregulation. Development of MT involves G protein-coupled receptors, and may be affected by aging. AIMS (1) to estimate the mesenteric blood flow in myogenically active small mesenteric arteries; (2) to investigate the signaling from Gαq/11 and/or Gα12 activation to MT development; (3) to investigate the role of Rho-kinase 2 and aging on MT in mesenteric resistance arteries. METHODS we used pressure myography, quantitative real-time PCR, and immunolocalization to study small (<200 μm) mesenteric arteries (SMA) from young, mature adult, and middle aged mice. RESULTS Poiseuille flow calculations indicated autoregulation of blood flow at 60-120 mm Hg arterial pressure. Gαq/11 and Gα12 were abundantly expressed at the mRNA and protein levels in SMA. The Gαq/11 inhibitor YM-254890 suppressed MT development, and the Phosholipase C inhibitors U73122 and ET-18-OCH3 robustly inhibited it. We found an age-dependent increase in ROCK2 mRNA expression, and in basal MT. The specific ROCK2 inhibitor KD025 robustly inhibited MT in SMAs in all mice with an age-dependent variation in KD025 sensitivity. The inhibitory effect of KD025 was not prevented by the L-type Ca2+ channel activator BayK 8644. KD025 reversibly inhibited MT and endothelin-1 vasoconstriction in small pial arteries from Göttingen minipigs. CONCLUSIONS MT development in SMAs occurs through a Gαq/11 /PLC/Ca2+ -dependent pathway, and is maintained via ROCK2-mediated Ca2+ sensitization. Increased MT at mature adulthood can be explained by increased ROCK2 expression/activity.
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Affiliation(s)
- Karl Björling
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Philomeena D. Joseph
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Kristian Egebjerg
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Max Salomonsson
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagen NDenmark
- Department of Internal MedicineTrelleborg HospitalTrelleborgSweden
| | | | | | - Lars J. Jensen
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
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59
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Eid AH, El-Yazbi AF, Zouein F, Arredouani A, Ouhtit A, Rahman MM, Zayed H, Pintus G, Abou-Saleh H. Inositol 1,4,5-Trisphosphate Receptors in Hypertension. Front Physiol 2018; 9:1018. [PMID: 30093868 PMCID: PMC6071574 DOI: 10.3389/fphys.2018.01018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 07/09/2018] [Indexed: 12/21/2022] Open
Abstract
Chronic hypertension remains a major cause of global mortality and morbidity. It is a complex disease that is the clinical manifestation of multiple genetic, environmental, nutritional, hormonal, and aging-related disorders. Evidence supports a role for vascular aging in the development of hypertension involving an impairment in endothelial function together with an alteration in vascular smooth muscle cells (VSMCs) calcium homeostasis leading to increased myogenic tone. Changes in free intracellular calcium levels ([Ca2+] i ) are mediated either by the influx of Ca2+ from the extracellular space or release of Ca2+ from intracellular stores, mainly the sarcoplasmic reticulum (SR). The influx of extracellular Ca2+ occurs primarily through voltage-gated Ca2+ channels (VGCCs), store-operated Ca2+ channels (SOC), and Ca2+ release-activated channels (CRAC), whereas SR-Ca2+ release occurs through inositol trisphosphate receptor (IP3R) and ryanodine receptors (RyRs). IP3R-mediated SR-Ca2+ release, in the form of Ca2+ waves, not only contributes to VSMC contraction and regulates VGCC function but is also intimately involved in structural remodeling of resistance arteries in hypertension. This involves a phenotypic switch of VSMCs as well as an alteration of cytoplasmic Ca2+ signaling machinery, a phenomena tightly related to the aging process. Several lines of evidence implicate changes in expression/function levels of IP3R isoforms in the development of hypertension, VSMC phenotypic switch, and vascular aging. The present review discusses the current knowledge of these mechanisms in an integrative approach and further suggests potential new targets for hypertension management and treatment.
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Affiliation(s)
- Ali H Eid
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.,Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Ahmed F El-Yazbi
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon.,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Fouad Zouein
- Department of Pharmacology and Toxicology, Faculty of Medicine, American University of Beirut, Beirut, Lebanon
| | - Abdelilah Arredouani
- Qatar Biomedical Research Institute, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
| | - Allal Ouhtit
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Md M Rahman
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
| | - Hatem Zayed
- Department of Biomedical Sciences, College of Health Sciences, Qatar University, Doha, Qatar
| | - Gianfranco Pintus
- Department of Biomedical Sciences, College of Health Sciences, Qatar University, Doha, Qatar
| | - Haissam Abou-Saleh
- Department of Biological and Environmental Sciences, College of Arts and Sciences, Qatar University, Doha, Qatar
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GsMTx4-D provides protection to the D2.mdx mouse. Neuromuscul Disord 2018; 28:868-877. [PMID: 30174173 DOI: 10.1016/j.nmd.2018.07.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Revised: 07/02/2018] [Accepted: 07/17/2018] [Indexed: 12/23/2022]
Abstract
Duchenne muscular dystrophy is a life-limiting muscle disease that has no current effective therapy. Despite mounting evidence that dysregulation of mechanosensitive ion channels is a significant contributor to dystrophy pathogenesis, effective pharmacologic strategies targeting these channels are lacking. GsMTx4, and its enantiomer GsMTx4-D, are peptide inhibitors of mechanosensitive channels with identical activity. In previous studies, acute in vitro application of GsMTx4 to dystrophic murine muscle effectively reduced the excess MSC dependent calcium influx linked to contraction-induced muscle damage. Here we sought to determine if in vivo treatment with GsMTx4-D proffered benefit in the D2.mdx mouse. GsMTx4-D showed a 1-week half-life when administered by subcutaneous injection over four weeks. Informed by these results, D2.mdx mice were then treated by a subcutaneous injection regimen of GsMTx4-D for six weeks followed by determination of muscle mass, muscle susceptibility to eccentric contraction injury and multiple histological indicators of disease progression. The mice showed a reduction in the loss of muscle mass and a decrease in susceptibility to contraction induced injury. These protective effects were realized without reduction in fibrosis, supporting a model where GsMTx4-D acts directly on muscle cells. We propose GsMTx4-D represents a promising new therapy to slow disease progression and may complement other therapies such as anti-inflammatory agents and gene-replacement strategies.
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Matin N, Pires PW, Garver H, Jackson WF, Dorrance AM. DOCA-salt hypertension impairs artery function in rat middle cerebral artery and parenchymal arterioles. Microcirculation 2018; 23:571-579. [PMID: 27588564 DOI: 10.1111/micc.12308] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 08/30/2016] [Indexed: 01/25/2023]
Abstract
OBJECTIVE Chronic hypertension induces detrimental changes in the structure and function of surface cerebral arteries. Very little is known about PAs, which perfuse distinct neuronal populations in the cortex and may play a role in cerebrovascular disorders. We investigated the effect of DOCA-salt induced hypertension on endothelial function and artery structure in PAs and MCAs. METHODS Uninephrectomized male Sprague-Dawley rats were implanted with a subcutaneous pellet containing DOCA (150 mg/kg b.w.) and drank salt water (1% NaCl and 0.2% KCl) for 4 weeks. Sham rats were uninephrectomized and drank tap water. Vasoreactivity and passive structure in the MCAs and the PAs were assessed by pressure myography. RESULTS Both MCAs and PAs from DOCA-salt rats exhibited impaired endothelium-dependent dilation (P<.05). In the PAs, addition of NO and COX inhibitors enhanced dilation in DOCA-salt rats (P<.05), suggesting that dysfunctional NO and COX-dependent signaling could contribute to impaired endothelium-mediated dilation. MCAs from DOCA-salt rats exhibited inward remodeling (P<.05). CONCLUSIONS Hypertension-induced MCA remodeling coupled with impaired endothelium-dependent dilation in both the MCAs and PAs may exacerbate the risk of cerebrovascular accidents and the associated morbidity and mortality.
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Affiliation(s)
- Nusrat Matin
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA.
| | - Paulo W Pires
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA.,Department of Pharmacology, Center for Cardiovascular Research, University of Nevada School of Medicine, Reno, NV, USA
| | - Hannah Garver
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
| | - Anne M Dorrance
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI, USA
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Pritchard HAT, Gonzales AL, Pires PW, Drumm BT, Ko EA, Sanders KM, Hennig GW, Earley S. Microtubule structures underlying the sarcoplasmic reticulum support peripheral coupling sites to regulate smooth muscle contractility. Sci Signal 2017; 10:eaan2694. [PMID: 28928237 PMCID: PMC6328376 DOI: 10.1126/scisignal.aan2694] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Junctional membrane complexes facilitate excitation-contraction coupling in skeletal and cardiac muscle cells by forming subcellular invaginations that maintain close (≤20 nm) proximity of ryanodine receptors (RyRs) on the sarcoplasmic reticulum (SR) with voltage-dependent Ca2+ channels in the plasma membrane. In fully differentiated smooth muscle cells, junctional membrane complexes occur as distributed sites of peripheral coupling. We investigated the role of the cytoskeleton in maintaining peripheral coupling and associated Ca2+ signaling networks within native smooth muscle cells of mouse and rat cerebral arteries. Using live-cell confocal and superresolution microscopy, we found that the tight interactions between the SR and the plasma membrane in these cells relied on arching microtubule structures present at the periphery of smooth muscle cells and were independent of the actin cytoskeleton. Loss of peripheral coupling associated with microtubule depolymerization altered the spatiotemporal properties of localized Ca2+ sparks generated by the release of Ca2+ through type 2 RyRs (RyR2s) on the SR and decreased the number of sites of colocalization between RyR2s and large-conductance Ca2+-activated K+ (BK) channels. The reduced BK channel activity associated with the loss of SR-plasma membrane interactions was accompanied by increased pressure-induced constriction of cerebral resistance arteries. We conclude that microtubule structures maintain peripheral coupling in contractile smooth muscle cells, which is crucial for the regulation of contractility and cerebral vascular tone.
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Affiliation(s)
- Harry A T Pritchard
- Department of Pharmacology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Albert L Gonzales
- Department of Pharmacology, University of Vermont, Burlington, VT 05405, USA
| | - Paulo W Pires
- Department of Pharmacology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Bernard T Drumm
- Department of Physiology and Cell Biology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Eun A Ko
- Department of Physiology and Cell Biology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Kenton M Sanders
- Department of Physiology and Cell Biology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA
| | - Grant W Hennig
- Department of Pharmacology, University of Vermont, Burlington, VT 05405, USA
| | - Scott Earley
- Department of Pharmacology, Center for Cardiovascular Research, University of Nevada, Reno School of Medicine, Reno, NV 89557, USA.
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IP 3 receptor signaling and endothelial barrier function. Cell Mol Life Sci 2017; 74:4189-4207. [PMID: 28803370 DOI: 10.1007/s00018-017-2624-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 07/18/2017] [Accepted: 08/08/2017] [Indexed: 12/14/2022]
Abstract
The endothelium, a monolayer of endothelial cells lining vessel walls, maintains tissue-fluid homeostasis by restricting the passage of the plasma proteins and blood cells into the interstitium. The ion Ca2+, a ubiquitous secondary messenger, initiates signal transduction events in endothelial cells that is critical to control of vascular tone and endothelial permeability. The ion Ca2+ is stored inside the intracellular organelles and released into the cytosol in response to environmental cues. The inositol 1,4,5-trisphosphate (IP3) messenger facilitates Ca2+ release through IP3 receptors which are Ca2+-selective intracellular channels located within the membrane of the endoplasmic reticulum. Binding of IP3 to the IP3Rs initiates assembly of IP3R clusters, a key event responsible for amplification of Ca2+ signals in endothelial cells. This review discusses emerging concepts related to architecture and dynamics of IP3R clusters, and their specific role in propagation of Ca2+ signals in endothelial cells.
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Suchyna TM. Piezo channels and GsMTx4: Two milestones in our understanding of excitatory mechanosensitive channels and their role in pathology. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2017; 130:244-253. [PMID: 28778608 DOI: 10.1016/j.pbiomolbio.2017.07.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 07/17/2017] [Accepted: 07/21/2017] [Indexed: 12/19/2022]
Abstract
Discovery of Piezo channels and the reporting of their sensitivity to the inhibitor GsMTx4 were important milestones in the study of non-selective cationic mechanosensitive channels (MSCs) in normal physiology and pathogenesis. GsMTx4 had been used for years to investigate the functional role of cationic MSCs, especially in muscle tissue, but with little understanding of its target or inhibitory mechanism. The sensitivity of Piezo channels to bilayer stress and its robust mechanosensitivity when expressed in heterologous systems were keys to determining GsMTx4's mechanism of action. However, questions remain regarding Piezo's role in muscle function due to the non-selective nature of GsMTx4 inhibition toward membrane mechanoenzymes and the implication of MCS channel types by genetic knockdown. Evidence supporting Piezo like activity, at least in the developmental stages of muscle, is presented. While the MSC targets of GsMTx4 in muscle pathology are unclear, its muscle protective effects are clearly demonstrated in two recent in situ studies on normal cardiomyocytes and dystrophic skeletal muscle. The muscle protective function may be due to the combined effect of GsMTx4's inhibitory action on cationic MSCs like Piezo and TRP, and its potentiation of repolarizing K+ selective MSCs like K2P and SAKCa. Paradoxically, the potent in vitro action of GsMTx4 on many physiological functions seems to conflict with its lack of in situ side-effects on normal animal physiology. Future investigations into cytoskeletal control of sarcolemma mechanics and the suspected inclusion of MSCs in membrane micro/nano sized domains with distinct mechanical properties will aide our understanding of this dichotomy.
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Affiliation(s)
- Thomas M Suchyna
- University of Buffalo, Dept. of Physiology and Biophysics, Buffalo, NY, USA.
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Pires PW, Ko E, Pritchard HA, Rudokas M, Yamasaki E, Earley S. The angiotensin II receptor type 1b is the primary sensor of intraluminal pressure in cerebral artery smooth muscle cells. J Physiol 2017; 595:4735-4753. [PMID: 28475214 PMCID: PMC5509855 DOI: 10.1113/jp274310] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 05/03/2017] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS The angiotensin II receptor type 1b (AT1 Rb ) is the primary sensor of intraluminal pressure in cerebral arteries. Pressure or membrane-stretch induced stimulation of AT1 Rb activates the TRPM4 channel and results in inward transient cation currents that depolarize smooth muscle cells, leading to vasoconstriction. Activation of either AT1 Ra or AT1 Rb with angiotensin II stimulates TRPM4 currents in cerebral artery myocytes and vasoconstriction of cerebral arteries. The expression of AT1 Rb mRNA is ∼30-fold higher than AT1 Ra in whole cerebral arteries and ∼45-fold higher in isolated cerebral artery smooth muscle cells. Higher levels of expression are likely to account for the obligatory role of AT1 Rb for pressure-induced vasoconstriction. ABSTRACT: Myogenic vasoconstriction, which reflects the intrinsic ability of smooth muscle cells to contract in response to increases in intraluminal pressure, is critically important for the autoregulation of blood flow. In smooth muscle cells from cerebral arteries, increasing intraluminal pressure engages a signalling cascade that stimulates cation influx through transient receptor potential (TRP) melastatin 4 (TRPM4) channels to cause membrane depolarization and vasoconstriction. Substantial evidence indicates that the angiotensin II receptor type 1 (AT1 R) is inherently mechanosensitive and initiates this signalling pathway. Rodents express two types of AT1 R - AT1 Ra and AT1 Rb - and conflicting studies provide support for either isoform as the primary sensor of intraluminal pressure in peripheral arteries. We hypothesized that mechanical activation of AT1 Ra increases TRPM4 currents to induce myogenic constriction of cerebral arteries. However, we found that development of myogenic tone was greater in arteries from AT1 Ra knockout animals compared with controls. In patch-clamp experiments using native cerebral arterial myocytes, membrane stretch-induced cation currents were blocked by the TRPM4 inhibitor 9-phenanthrol in both groups. Further, the AT1 R blocker losartan (1 μm) diminished myogenic tone and blocked stretch-induced cation currents in cerebral arteries from both groups. Activation of AT1 R with angiotensin II (30 nm) also increased TRPM4 currents in smooth muscle cells and constricted cerebral arteries from both groups. Expression of AT1 Rb mRNA was ∼30-fold greater than AT1 Ra in cerebral arteries, and knockdown of AT1 Rb selectively diminished myogenic constriction. We conclude that AT1 Rb , acting upstream of TRPM4 channels, is the primary sensor of intraluminal pressure in cerebral artery smooth muscle cells.
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Affiliation(s)
- Paulo W. Pires
- Department of Pharmacology, Center for Cardiovascular Research, University of NevadaReno School of MedicineRenoNV89557‐0318USA
| | - Eun‐A. Ko
- Department of Physiology and Cell Biology, University of NevadaReno School of MedicineRenoNV89557‐0318USA
| | - Harry A.T. Pritchard
- Department of Pharmacology, Center for Cardiovascular Research, University of NevadaReno School of MedicineRenoNV89557‐0318USA
| | - Michael Rudokas
- Department of Pharmacology, Center for Cardiovascular Research, University of NevadaReno School of MedicineRenoNV89557‐0318USA
| | - Evan Yamasaki
- Department of Pharmacology, Center for Cardiovascular Research, University of NevadaReno School of MedicineRenoNV89557‐0318USA
| | - Scott Earley
- Department of Pharmacology, Center for Cardiovascular Research, University of NevadaReno School of MedicineRenoNV89557‐0318USA
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Jackson WF, Boerman EM. Regional heterogeneity in the mechanisms of myogenic tone in hamster arterioles. Am J Physiol Heart Circ Physiol 2017; 313:H667-H675. [PMID: 28667050 DOI: 10.1152/ajpheart.00183.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 06/07/2017] [Accepted: 06/26/2017] [Indexed: 01/30/2023]
Abstract
Myogenic tone is an important feature of arterioles and resistance arteries, but the mechanisms responsible for this hallmark characteristic remain unclear. We used pharmacological inhibitors to compare the roles played by phospholipase C (PLC; 10 μM U73122), inositol 1,4,5-trisphosphate receptors (IP3Rs; 100 μM 2-aminoethoxydiphenylborane), protein kinase C (10 μM bisindolylmaleimide I), angiotensin II type 1 receptors (1 μM losartan), Rho kinase (10 nM-30 μM Y27632 or 300 nM H1152), stretch-activated ion channels (10 nM-1 μM Gd3+ or 5 μM spider venom toxin GsMTx-4) and L-type voltage-gated Ca2+ channels (0.3-100 μM diltiazem) in myogenic tone of cannulated, pressurized (80 cmH2O), second-order hamster cremaster or cheek pouch arterioles. Effective inhibition of either PLC or IP3Rs dilated cremaster arterioles, inhibited Ca2+ waves, and reduced global Ca2+ levels. In contrast, cheek pouch arterioles did not display Ca2+ waves and inhibition of PLC or IP3Rs had no effect on myogenic tone or intracellular Ca2+ levels. Inhibition of Rho kinase dilated both cheek pouch and cremaster arterioles with equal efficacy and potency but also reduced intracellular Ca2+ signals in both arterioles. Similarly, inhibition of mechanosensitive ion channels with Gd2+ or GsMTx-4 produced comparable dilation in both arterioles. Inhibition of L-type Ca2+ channels with diltiazem was more effective in dilating cremaster (86 ± 5% dilation, n = 4) than cheek pouch arterioles (54 ± 4% dilation, n = 6, P < 0.05). Thus, there are substantial differences in the mechanisms underlying myogenic tone in hamster cremaster and cheek pouch arterioles. Regional heterogeneity in myogenic mechanisms could provide new targets for drug development to improve regional blood flow in a tissue-specific manner.NEW & NOTEWORTHY Regional heterogeneity in the mechanisms of pressure-induced myogenic tone implies that resistance vessels may be able to alter myogenic signaling pathways to adapt to their environment. A better understanding of the spectrum of myogenic mechanisms could provide new targets to treat diseases that affect resistance artery and arteriolar function.
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Affiliation(s)
- William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
| | - Erika M Boerman
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan
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Provence A, Rovner ES, Petkov GV. Regulation of transient receptor potential melastatin 4 channel by sarcoplasmic reticulum inositol trisphosphate receptors: Role in human detrusor smooth muscle function. Channels (Austin) 2017. [PMID: 28644055 DOI: 10.1080/19336950.2017.1341023] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
We recently reported key physiologic roles for Ca2+-activated transient receptor potential melastatin 4 (TRPM4) channels in detrusor smooth muscle (DSM). However, the Ca2+-signaling mechanisms governing TRPM4 channel activity in human DSM cells are unexplored. As the TRPM4 channels are activated by Ca2+, inositol 1,4,5-trisphosphate receptor (IP3R)-mediated Ca2+ release from the sarcoplasmic reticulum represents a potential Ca2+ source for TRPM4 channel activation. We used clinically-characterized human DSM tissues to investigate the molecular and functional interactions of the IP3Rs and TRPM4 channels. With in situ proximity ligation assay (PLA) and perforated patch-clamp electrophysiology, we tested the hypothesis that TRPM4 channels are tightly associated with the IP3Rs and are activated by IP3R-mediated Ca2+ release in human DSM. With in situ PLA, we demonstrated co-localization of the TRPM4 channels and IP3Rs in human DSM cells. As the TRPM4 channels and IP3Rs must be located within close apposition to functionally interact, these findings support the concept of a potential Ca2+-mediated TRPM4-IP3R regulatory mechanism. To investigate IP3R regulation of TRPM4 channel activity, we sought to determine the consequences of IP3R pharmacological inhibition on TRPM4 channel-mediated transient inward cation currents (TICCs). In freshly-isolated human DSM cells, blocking the IP3Rs with the selective IP3R inhibitor xestospongin-C significantly decreased TICCs. The data suggest that IP3Rs have a key role in mediating the Ca2+-dependent activation of TRPM4 channels in human DSM. The study provides novel insight into the molecular and cellular mechanisms regulating TRPM4 channels by revealing that TRPM4 channels and IP3Rs are spatially and functionally coupled in human DSM.
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Affiliation(s)
- Aaron Provence
- a Department of Drug Discovery and Biomedical Sciences , South Carolina College of Pharmacy, University of South Carolina , Columbia , SC , USA
| | - Eric S Rovner
- b Department of Urology , Medical University of South Carolina , Charleston , SC , USA
| | - Georgi V Petkov
- a Department of Drug Discovery and Biomedical Sciences , South Carolina College of Pharmacy, University of South Carolina , Columbia , SC , USA.,b Department of Urology , Medical University of South Carolina , Charleston , SC , USA.,c Department of Pharmaceutical Sciences , College of Pharmacy, University of Tennessee Health Science Center , Memphis , TN , USA
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Tajada S, Moreno CM, O'Dwyer S, Woods S, Sato D, Navedo MF, Santana LF. Distance constraints on activation of TRPV4 channels by AKAP150-bound PKCα in arterial myocytes. J Gen Physiol 2017; 149:639-659. [PMID: 28507079 PMCID: PMC5460949 DOI: 10.1085/jgp.201611709] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 03/03/2017] [Accepted: 04/27/2017] [Indexed: 11/20/2022] Open
Abstract
Vascular smooth muscle tone can be regulated by angiotensin II, which enhances TRPV4 channel activity via AKAP150-bound protein kinase C. Tajada et al. show that the effect of AKAP150 on TRPV4 channels is inversely proportional to the distance between them, which varies with sex and arterial bed. TRPV4 (transient receptor potential vanilloid 4) channels are Ca2+-permeable channels that play a key role in regulating vascular tone. In arterial myocytes, opening of TRPV4 channels creates local increases in Ca2+ influx, detectable optically as “TRPV4 sparklets.” TRPV4 sparklet activity can be enhanced by the action of the vasoconstrictor angiotensin II (AngII). This modulation depends on the activation of subcellular signaling domains that comprise protein kinase C α (PKCα) bound to the anchoring protein AKAP150. Here, we used super-resolution nanoscopy, patch-clamp electrophysiology, Ca2+ imaging, and mathematical modeling approaches to test the hypothesis that AKAP150-dependent modulation of TRPV4 channels is critically dependent on the distance between these two proteins in the sarcolemma of arterial myocytes. Our data show that the distance between AKAP150 and TRPV4 channel clusters varies with sex and arterial bed. Consistent with our hypothesis, we further find that basal and AngII-induced TRPV4 channel activity decays exponentially as the distance between TRPV4 and AKAP150 increases. Our data suggest a maximum radius of action of ∼200 nm for local modulation of TRPV4 channels by AKAP150-associated PKCα.
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Affiliation(s)
- Sendoa Tajada
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Claudia M Moreno
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Samantha O'Dwyer
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Sean Woods
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
| | - Daisuke Sato
- Department of Pharmacology, University of California Davis School of Medicine, Davis, CA
| | - Manuel F Navedo
- Department of Pharmacology, University of California Davis School of Medicine, Davis, CA
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, CA
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Src tyrosine kinases contribute to serotonin-mediated contraction by regulating calcium-dependent pathways in rat skeletal muscle arteries. Pflugers Arch 2017; 469:767-777. [DOI: 10.1007/s00424-017-1949-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 12/01/2016] [Accepted: 02/01/2017] [Indexed: 10/20/2022]
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Li Y, Brayden JE. Rho kinase activity governs arteriolar myogenic depolarization. J Cereb Blood Flow Metab 2017; 37:140-152. [PMID: 26661251 PMCID: PMC5363734 DOI: 10.1177/0271678x15621069] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/10/2015] [Accepted: 11/11/2015] [Indexed: 11/15/2022]
Abstract
Cerebral arterioles contribute critically to regulation of local and global blood flow within the brain. Dysfunction of these blood vessels is implicated in numerous cardiovascular diseases. However, treatments are limited due to incomplete understanding of fundamental control mechanisms at this level of circulation. Emerging evidence points to a key role of Rho-associated protein kinase in regulation of microvascular contractility. This study sought to decipher the mechanisms of Rho-associated protein kinase-mediated myogenic vasoconstriction in cerebral parenchymal arterioles. Here, we report that the Rho-associated protein kinase inhibitor H1152 strongly attenuated pressure-induced constriction, cytosolic [Ca2+] increases, and depolarization of isolated parenchymal arterioles. Further, the RhoA activator CN03 potentiated parenchymal arteriole myogenic constriction and depolarization, indicating important involvement of RhoA/Rho-associated protein kinase signaling in myogenic excitation-contraction mechanisms. Because of the well-established role of TRPM4 in pressure-induced depolarization, possible modulatory effects of Rho-associated protein kinase on TRPM4 currents were explored using patch clamp electrophysiology. TRPM4 currents were suppressed by H1152 and enhanced by CN03. Finally, H1152 elevated the apparent [Ca2+]-threshold for TRPM4 activation, suggesting that Rho-associated protein kinase activates TRPM4 by increasing its Ca2+-sensitivity. Our results support a novel mechanism whereby Rho-associated protein kinase-mediated myogenic vasoconstriction occurs primarily through activation of TRPM4 channels, smooth muscle depolarization, and cytosolic [Ca2+] increases in cerebral arterioles.
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Affiliation(s)
- Yao Li
- Department of Pharmacology, University of Vermont, Burlington, VT, USA
| | - Joseph E Brayden
- Department of Pharmacology, University of Vermont, Burlington, VT, USA
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Álvarez-Miguel I, Cidad P, Pérez-García MT, López-López JR. Differences in TRPC3 and TRPC6 channels assembly in mesenteric vascular smooth muscle cells in essential hypertension. J Physiol 2016; 595:1497-1513. [PMID: 27861908 DOI: 10.1113/jp273327] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/07/2016] [Indexed: 01/29/2023] Open
Abstract
KEY POINTS Canonical transient receptor potential (TRPC)3 and TRPC6 channels of vascular smooth muscle cells (VSMCs) mediate stretch- or agonist-induced cationic fluxes, contributing to membrane potential and vascular tone. Native TRPC3/C6 channels can form homo- or heterotetrameric complexes, which can hinder individual TRPC channel properties. The possibility that the differences in their association pattern may change their contribution to vascular tone in hypertension is unexplored. Functional characterization of heterologously expressed channels showed that TRPC6-containing complexes exhibited Pyr3/Pyr10-sensitive currents, whereas TRPC3-mediated currents were blocked by anti-TRPC3 antibodies. VSMCs from hypertensive (blood pressure high; BPH) mice have larger cationic basal currents insensitive to Pyr10 and sensitive to anti-TRPC3 antibodies. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN (blood pressure normal) mesenteric arteries. We conclude that the increased TRPC3 channel expression in BPH VSMCs leads to changes in TRPC3/C6 heteromultimeric assembly, with a higher TRPC3 channel contribution favouring depolarization of hypertensive VSMCs. ABSTRACT Increased vascular tone in essential hypertension involves a sustained rise in total peripheral resistance. A model has been proposed in which the combination of membrane depolarization and higher L-type Ca2+ channel activity generates augmented Ca2+ influx into vascular smooth muscle cells (VSMCs), contraction and vasoconstriction. The search for culprit ion channels responsible for membrane depolarization has provided several candidates, including members of the canonical transient receptor potential (TRPC) family. TRPC3 and TRPC6 are diacylglycerol-activated, non-selective cationic channels contributing to stretch- or agonist-induced depolarization. Conflicting information exists regarding changes in TRPC3/TRPC6 functional expression in hypertension. However, although TRPC3-TRPC6 channels can heteromultimerize, the possibility that differences in their association pattern may change their functional contribution to vascular tone is largely unexplored. We probe this hypothesis using a model of essential hypertension (BPH mice; blood pressure high) and its normotensive control (BPN mice; blood pressure normal). First, non-selective cationic currents through homo- and heterotetramers recorded from transfected Chinese hamster ovary cells indicated that TRPC currents were sensitive to the selective antagonist Pyr10 only when TRPC6 was present, whereas intracellular anti-TRPC3 antibody selectively blocked TRPC3-mediated currents. In mesenteric VSMCs, basal and agonist-induced currents were more sensitive to Pyr3 and Pyr10 in BPN cells. Consistently, myography studies showed a larger Pyr3/10-induced vasodilatation in BPN mesenteric arteries. mRNA and protein expression data supported changes in TRPC3 and TRPC6 proportions and assembly, with a higher TRPC3 channel contribution in BPH VSMCs that could favour cell depolarization. These differences in functional and pharmacological properties of TRPC3 and TRPC6 channels, depending on their assembly, could represent novel therapeutical opportunities.
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Affiliation(s)
- Inés Álvarez-Miguel
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - Pilar Cidad
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - M Teresa Pérez-García
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
| | - José Ramón López-López
- Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), Valladolid, Spain
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Effects of transient receptor potential canonical 1 (TRPC1) on the mechanical stretch-induced expression of airway remodeling-associated factors in human bronchial epithelioid cells. J Biomech 2016; 51:89-96. [PMID: 27986325 DOI: 10.1016/j.jbiomech.2016.12.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 11/15/2016] [Accepted: 12/04/2016] [Indexed: 02/06/2023]
Abstract
Research has shown that mechanical stress stimulation can cause airway remodeling. We investigate the effects of mechanical stretch on the expression of the airway remodeling-associated factors interleukin-13 (IL-13) and matrix metalloprotein-9 (MMP-9) and signaling pathways in human bronchial epithelioid (16HBE) cells under mechanical stretch. A Flexcell FX-4000 Tension System with a flexible substrate was applied to stretch 16HBE cells at a 15% elongation amplitude and 1Hz frequency, with stretching for 0.5h, 1h, 1.5h and 2h. The experimental group with higher IL-13, MMP-9, and TRPC1 expression and higher Ca2+ levels was selected for performing intervention experiment. These cells were pretreated with the transient receptor potential canonical 1 (TRPC1) channel antagonist SKF96365 and TRPC1-specific siRNA, and then mechanical stretch was applied. Our results provided evidences that mechanical pressure significantly increased IL-13, MMP-9, and TRPC1 protein and mRNA expression levels and intracellular Ca2+ fluorescence intensity at 4 time points compared with the control group. The peak IL-13, MMP-9, and TRPC1 expression levels were observed at 0.5h after exposure to mechanical pressure. IL-13 and MMP-9 expression levels and Ca2+ fluorescence intensity in the stretch+SKF96365 group and in the stretch+TRPC1 siRNA group were significantly lower than those were in the mechanical stretch group. By incubating the cells with the intracellular calcium chelator BAPTA-AM, the expression of IL-13 and MMP9 was significantly decreased, and the expression level of TRPC1 remained unchanged. These observations suggest that mechanical stretch may induce an influx of Ca2+ and up-regulation of IL-13 and MMP-9 expression in 16HBE cells via activation of TRPC1.
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Hong K, Zhao G, Hong Z, Sun Z, Yang Y, Clifford PS, Davis MJ, Meininger GA, Hill MA. Mechanical activation of angiotensin II type 1 receptors causes actin remodelling and myogenic responsiveness in skeletal muscle arterioles. J Physiol 2016; 594:7027-7047. [PMID: 27531064 PMCID: PMC5134373 DOI: 10.1113/jp272834] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 08/09/2016] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS Candesartan, an inverse agonist of the type 1 angiotensin II receptor (AT1 R), causes a concentration-dependent inhibition of pressure-dependent myogenic tone consistent with previous reports of mechanosensitivity of this G protein-coupled receptor. Mechanoactivation of the AT1 R occurs independently of local angiotensin II production and the type 2 angiotensin receptor. Mechanoactivation of the AT1 R stimulates actin polymerization by a protein kinase C-dependent mechanism, but independently of a change in intracellular Ca2+ . Using atomic force microscopy, changes in single vascular smooth muscle cell cortical actin are observed to remodel following mechanoactivation of the AT1 R. ABSTRACT The Gq/11 protein-coupled angiotensin II type 1 receptor (AT1 R) has been shown to be activated by mechanical stimuli. In the vascular system, evidence supports the AT1 R being a mechanosensor that contributes to arteriolar myogenic constriction. The aim of this study was to determine if AT1 R mechanoactivation affects myogenic constriction in skeletal muscle arterioles and to determine underlying cellular mechanisms. Using pressure myography to study rat isolated first-order cremaster muscle arterioles the AT1 R inhibitor candesartan (10-7 -10-5 m) showed partial but concentration-dependent inhibition of myogenic reactivity. Inhibition was demonstrated by a rightward shift in the pressure-diameter relationship over the intraluminal pressure range, 30-110 mmHg. Pressure-induced changes in global vascular smooth muscle intracellular Ca2+ (using Fura-2) were similar in the absence or presence of candesartan, indicating that AT1 R-mediated myogenic constriction relies on Ca2+ -independent downstream signalling. The diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG) reversed the inhibitory effect of candesartan, while this rescue effect was prevented by the protein kinase C (PKC) inhibitor GF 109203X. Both candesartan and PKC inhibition caused increased G-actin levels, as determined by Western blotting of vessel lysates, supporting involvement of cytoskeletal remodelling. At the single vascular smooth muscle cell level, atomic force microscopy showed that cell swelling (stretch) with hypotonic buffer also caused thickening of cortical actin fibres and this was blocked by candesartan. Collectively, the present studies support growing evidence for novel modes of activation of the AT1 R in arterioles and suggest that mechanically activated AT1 R generates diacylglycerol, which in turn activates PKC which induces the actin cytoskeleton reorganization that is required for pressure-induced vasoconstriction.
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Affiliation(s)
- Kwangseok Hong
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
- Robert M. Berne Cardiovascular Research Centre and Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA22908USA
| | - Guiling Zhao
- College of Applied Health SciencesUniversity of Illinois at ChicagoChicagoIL60612USA
| | - Zhongkui Hong
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Biomedical EngineeringUniversity of South DakotaSioux FallsSD57107USA
| | - Zhe Sun
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Yan Yang
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
| | - Philip S. Clifford
- College of Applied Health SciencesUniversity of Illinois at ChicagoChicagoIL60612USA
| | - Michael J. Davis
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Gerald A. Meininger
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Michael A. Hill
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
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74
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Ghosh D, Syed AU, Prada MP, Nystoriak MA, Santana LF, Nieves-Cintrón M, Navedo MF. Calcium Channels in Vascular Smooth Muscle. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 78:49-87. [PMID: 28212803 DOI: 10.1016/bs.apha.2016.08.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Calcium (Ca2+) plays a central role in excitation, contraction, transcription, and proliferation of vascular smooth muscle cells (VSMs). Precise regulation of intracellular Ca2+ concentration ([Ca2+]i) is crucial for proper physiological VSM function. Studies over the last several decades have revealed that VSMs express a variety of Ca2+-permeable channels that orchestrate a dynamic, yet finely tuned regulation of [Ca2+]i. In this review, we discuss the major Ca2+-permeable channels expressed in VSM and their contribution to vascular physiology and pathology.
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Affiliation(s)
- D Ghosh
- University of California, Davis, CA, United States
| | - A U Syed
- University of California, Davis, CA, United States
| | - M P Prada
- University of California, Davis, CA, United States
| | - M A Nystoriak
- Diabetes and Obesity Center, University of Louisville, Louisville, KY, United States
| | - L F Santana
- University of California, Davis, CA, United States
| | | | - M F Navedo
- University of California, Davis, CA, United States.
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75
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Brozovich FV, Nicholson CJ, Degen CV, Gao YZ, Aggarwal M, Morgan KG. Mechanisms of Vascular Smooth Muscle Contraction and the Basis for Pharmacologic Treatment of Smooth Muscle Disorders. Pharmacol Rev 2016; 68:476-532. [PMID: 27037223 PMCID: PMC4819215 DOI: 10.1124/pr.115.010652] [Citation(s) in RCA: 298] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The smooth muscle cell directly drives the contraction of the vascular wall and hence regulates the size of the blood vessel lumen. We review here the current understanding of the molecular mechanisms by which agonists, therapeutics, and diseases regulate contractility of the vascular smooth muscle cell and we place this within the context of whole body function. We also discuss the implications for personalized medicine and highlight specific potential target molecules that may provide opportunities for the future development of new therapeutics to regulate vascular function.
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Affiliation(s)
- F V Brozovich
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - C J Nicholson
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - C V Degen
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - Yuan Z Gao
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - M Aggarwal
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - K G Morgan
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
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76
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Longden TA, Hill-Eubanks DC, Nelson MT. Ion channel networks in the control of cerebral blood flow. J Cereb Blood Flow Metab 2016; 36:492-512. [PMID: 26661232 PMCID: PMC4794103 DOI: 10.1177/0271678x15616138] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 09/17/2015] [Accepted: 10/14/2015] [Indexed: 12/26/2022]
Abstract
One hundred and twenty five years ago, Roy and Sherrington made the seminal observation that neuronal stimulation evokes an increase in cerebral blood flow.(1) Since this discovery, researchers have attempted to uncover how the cells of the neurovascular unit-neurons, astrocytes, vascular smooth muscle cells, vascular endothelial cells and pericytes-coordinate their activity to control this phenomenon. Recent work has revealed that ionic fluxes through a diverse array of ion channel species allow the cells of the neurovascular unit to engage in multicellular signaling processes that dictate local hemodynamics.In this review we center our discussion on two major themes: (1) the roles of ion channels in the dynamic modulation of parenchymal arteriole smooth muscle membrane potential, which is central to the control of arteriolar diameter and therefore must be harnessed to permit changes in downstream cerebral blood flow, and (2) the striking similarities in the ion channel complements employed in astrocytic endfeet and endothelial cells, enabling dual control of smooth muscle from either side of the blood-brain barrier. We conclude with a discussion of the emerging roles of pericyte and capillary endothelial cell ion channels in neurovascular coupling, which will provide fertile ground for future breakthroughs in the field.
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Affiliation(s)
- Thomas A Longden
- Department of Pharmacology, University of Vermont, Burlington, VT, USA
| | | | - Mark T Nelson
- Department of Pharmacology, University of Vermont, Burlington, VT, USA Institute of Cardiovascular Sciences, University of Manchester, Manchester, UK
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77
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Pires PW, Earley S. A TRPC3 signalling complex promotes cerebral artery remodelling during hypertension. Cardiovasc Res 2015; 109:4-5. [PMID: 26614778 DOI: 10.1093/cvr/cvv261] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Paulo Wagner Pires
- Department of Pharmacology, Center for Cardiovascular Research, University of Nevada School of Medicine, Reno, NV 89557, USA
| | - Scott Earley
- Department of Pharmacology, Center for Cardiovascular Research, University of Nevada School of Medicine, Reno, NV 89557, USA
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78
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Colinas O, Moreno-Domínguez A, Zhu HL, Walsh EJ, Pérez-García MT, Walsh MP, Cole WC. α5-Integrin-mediated cellular signaling contributes to the myogenic response of cerebral resistance arteries. Biochem Pharmacol 2015; 97:281-91. [PMID: 26278977 DOI: 10.1016/j.bcp.2015.08.088] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/10/2015] [Indexed: 12/24/2022]
Abstract
The myogenic response of resistance arterioles and small arteries involving constriction in response to intraluminal pressure elevation and dilation on pressure reduction is fundamental to local blood flow regulation in the microcirculation. Integrins have garnered considerable attention in the context of initiating the myogenic response, but evidence indicative of mechanotransduction by integrin adhesions, for example established changes in tyrosine phosphorylation of key adhesion proteins, has not been obtained to substantiate this interpretation. Here, we evaluated the role of integrin adhesions and associated cellular signaling in the rat cerebral arterial myogenic response using function-blocking antibodies against α5β1-integrins, pharmacological inhibitors of focal adhesion kinase (FAK) and Src family kinase (SFK), an ultra-high-sensitivity western blotting technique, site-specific phosphoprotein antibodies to quantify adhesion and contractile filament protein phosphorylation, and differential centrifugation to determine G-actin levels in rat cerebral arteries at varied intraluminal pressures. Pressure-dependent increases in the levels of phosphorylation of FAK (FAK-Y397, Y576/Y577), SFK (SFK-Y416; Y527 phosphorylation was reduced), vinculin-Y1065, paxillin-Y118 and phosphoinositide-specific phospholipase C-γ1 (PLCγ1)-Y783 were detected. Treatment with α5-integrin function-blocking antibodies, FAK inhibitor FI-14 or SFK inhibitor SU6656 suppressed the changes in adhesion protein phosphorylation, and prevented pressure-dependent phosphorylation of the myosin targeting subunit of myosin light chain phosphatase (MYPT1) at T855 and 20kDa myosin regulatory light chains (LC20) at S19, as well as actin polymerization that are necessary for myogenic constriction. We conclude that mechanotransduction by integrin adhesions and subsequent cellular signaling play a fundamental role in the cerebral arterial myogenic response.
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Affiliation(s)
- Olaia Colinas
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Alejandro Moreno-Domínguez
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Hai-Lei Zhu
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Emma J Walsh
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - M Teresa Pérez-García
- Department of Physiology, Instituto de Biología y Genética Molecular, University of Valladolid, Valladolid, Spain.
| | - Michael P Walsh
- Smooth Muscle Research Group, Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - William C Cole
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
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79
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Cáceres M, Ortiz L, Recabarren T, Romero A, Colombo A, Leiva-Salcedo E, Varela D, Rivas J, Silva I, Morales D, Campusano C, Almarza O, Simon F, Toledo H, Park KS, Trimmer JS, Cerda O. TRPM4 Is a Novel Component of the Adhesome Required for Focal Adhesion Disassembly, Migration and Contractility. PLoS One 2015; 10:e0130540. [PMID: 26110647 PMCID: PMC4482413 DOI: 10.1371/journal.pone.0130540] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 05/21/2015] [Indexed: 11/18/2022] Open
Abstract
Cellular migration and contractility are fundamental processes that are regulated by a variety of concerted mechanisms such as cytoskeleton rearrangements, focal adhesion turnover, and Ca2+ oscillations. TRPM4 is a Ca2+-activated non-selective cationic channel (Ca2+-NSCC) that conducts monovalent but not divalent cations. Here, we used a mass spectrometry-based proteomics approach to identify putative TRPM4-associated proteins. Interestingly, the largest group of these proteins has actin cytoskeleton-related functions, and among these nine are specifically annotated as focal adhesion-related proteins. Consistent with these results, we found that TRPM4 localizes to focal adhesions in cells from different cellular lineages. We show that suppression of TRPM4 in MEFs impacts turnover of focal adhesions, serum-induced Ca2+ influx, focal adhesion kinase (FAK) and Rac activities, and results in reduced cellular spreading, migration and contractile behavior. Finally, we demonstrate that the inhibition of TRPM4 activity alters cellular contractility in vivo, affecting cutaneous wound healing. Together, these findings provide the first evidence, to our knowledge, for a TRP channel specifically localized to focal adhesions, where it performs a central role in modulating cellular migration and contractility.
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Affiliation(s)
- Mónica Cáceres
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California Davis, Davis, California, United States of America
| | - Liliana Ortiz
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Tatiana Recabarren
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Programa de Anatomía y Biología del Desarrollo, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Anibal Romero
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Alicia Colombo
- Programa de Anatomía y Biología del Desarrollo, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Elías Leiva-Salcedo
- Section on Cellular Signaling, Program in Developmental Biology, National Institute of Child Health and Human Development (NICHD), National Institute of Health, Bethesda, Maryland, United States of America
| | - Diego Varela
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - José Rivas
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Ian Silva
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Diego Morales
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Camilo Campusano
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Oscar Almarza
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Felipe Simon
- Departamento de Ciencias Biologicas, Facultad de Ciencias Biologicas, Universidad Andres Bello, Santiago, Chile
- Facultad de Medicina, Universidad Andres Bello, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
| | - Hector Toledo
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Kang-Sik Park
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California Davis, Davis, California, United States of America
- Department of Physiology, School of Medicine, Kyung Hee University, Seoul, Korea
| | - James S. Trimmer
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California Davis, Davis, California, United States of America
- Department of Physiology and Membrane Biology, School of Medicine, University of California Davis, Davis, California, United States of America
| | - Oscar Cerda
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Department of Neurobiology, Physiology and Behavior, College of Biological Sciences, University of California Davis, Davis, California, United States of America
- * E-mail:
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80
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Earley S, Brayden JE. Transient receptor potential channels in the vasculature. Physiol Rev 2015; 95:645-90. [PMID: 25834234 DOI: 10.1152/physrev.00026.2014] [Citation(s) in RCA: 298] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The mammalian genome encodes 28 distinct members of the transient receptor potential (TRP) superfamily of cation channels, which exhibit varying degrees of selectivity for different ionic species. Multiple TRP channels are present in all cells and are involved in diverse aspects of cellular function, including sensory perception and signal transduction. Notably, TRP channels are involved in regulating vascular function and pathophysiology, the focus of this review. TRP channels in vascular smooth muscle cells participate in regulating contractility and proliferation, whereas endothelial TRP channel activity is an important contributor to endothelium-dependent vasodilation, vascular wall permeability, and angiogenesis. TRP channels are also present in perivascular sensory neurons and astrocytic endfeet proximal to cerebral arterioles, where they participate in the regulation of vascular tone. Almost all of these functions are mediated by changes in global intracellular Ca(2+) levels or subcellular Ca(2+) signaling events. In addition to directly mediating Ca(2+) entry, TRP channels influence intracellular Ca(2+) dynamics through membrane depolarization associated with the influx of cations or through receptor- or store-operated mechanisms. Dysregulation of TRP channels is associated with vascular-related pathologies, including hypertension, neointimal injury, ischemia-reperfusion injury, pulmonary edema, and neurogenic inflammation. In this review, we briefly consider general aspects of TRP channel biology and provide an in-depth discussion of the functions of TRP channels in vascular smooth muscle cells, endothelial cells, and perivascular cells under normal and pathophysiological conditions.
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Affiliation(s)
- Scott Earley
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
| | - Joseph E Brayden
- Department of Pharmacology, University of Nevada School of Medicine, Reno, Nevada; and Department of Pharmacology, University of Vermont College of Medicine, Burlington, Vermont
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81
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Hill-Eubanks DC, Gonzales AL, Sonkusare SK, Nelson MT. Vascular TRP channels: performing under pressure and going with the flow. Physiology (Bethesda) 2015; 29:343-60. [PMID: 25180264 DOI: 10.1152/physiol.00009.2014] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Endothelial cells and smooth muscle cells of resistance arteries mediate opposing responses to mechanical forces acting on the vasculature, promoting dilation in response to flow and constriction in response to pressure, respectively. In this review, we explore the role of TRP channels, particularly endothelial TRPV4 and smooth muscle TRPC6 and TRPM4 channels, in vascular mechanosensing circuits, placing their putative mechanosensitivity in context with other proposed upstream and downstream signaling pathways.
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Affiliation(s)
| | - Albert L Gonzales
- Department of Pharmacology, University of Vermont, Burlington, Vermont
| | | | - Mark T Nelson
- Department of Pharmacology, University of Vermont, Burlington, Vermont
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82
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Mauban JRH, Zacharia J, Fairfax S, Wier WG. PC-PLC/sphingomyelin synthase activity plays a central role in the development of myogenic tone in murine resistance arteries. Am J Physiol Heart Circ Physiol 2015; 308:H1517-24. [PMID: 25888510 DOI: 10.1152/ajpheart.00594.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 04/03/2015] [Indexed: 11/22/2022]
Abstract
Myogenic tone is an intrinsic property of the vasculature that contributes to blood pressure control and tissue perfusion. Earlier investigations assigned a key role in myogenic tone to phospholipase C (PLC) and its products, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). Here, we used the PLC inhibitor, U-73122, and two other, specific inhibitors of PLC subtypes (PI-PLC and PC-PLC) to delineate the role of PLC in myogenic tone of pressurized murine mesenteric arteries. U-73122 inhibited depolarization-induced contractions (high external K(+) concentration), thus confirming reports of nonspecific actions of U-73122 and its limited utility for studies of myogenic tone. Edelfosine, a specific inhibitor of PI-PLC, did not affect depolarization-induced contractions but modulated myogenic tone. Because PI-PLC produces IP3, we investigated the effect of blocking IP3 receptor-mediated Ca(2+) release on myogenic tone. Incubation of arteries with xestospongin C did not affect tone, consistent with the virtual absence of Ca(2+) waves in arteries with myogenic tone. D-609, an inhibitor of PC-PLC and sphingomyelin synthase, strongly inhibited myogenic tone and had no effect on depolarization-induced contraction. D-609 appeared to act by lowering cytoplasmic Ca(2+) concentration to levels below those that activate contraction. Importantly, incubation of pressurized arteries with a membrane-permeable analog of DAG induced vasoconstriction. The results therefore mandate a reexamination of the signaling pathways activated by the Bayliss mechanism. Our results suggest that PI-PLC and IP3 are not required in maintaining myogenic tone, but DAG, produced by PC-PLC and/or SM synthase, is likely through multiple mechanisms to increase Ca(2+) entry and promote vasoconstriction.
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Affiliation(s)
- Joseph R H Mauban
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Joseph Zacharia
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Seth Fairfax
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Withrow Gil Wier
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
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83
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Béziau DM, Toussaint F, Blanchette A, Dayeh NR, Charbel C, Tardif JC, Dupuis J, Ledoux J. Expression of phosphoinositide-specific phospholipase C isoforms in native endothelial cells. PLoS One 2015; 10:e0123769. [PMID: 25875657 PMCID: PMC4395365 DOI: 10.1371/journal.pone.0123769] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 02/25/2015] [Indexed: 11/18/2022] Open
Abstract
Phospholipase C (PLC) comprises a superfamily of enzymes that play a key role in a wide array of intracellular signalling pathways, including protein kinase C and intracellular calcium. Thirteen different mammalian PLC isoforms have been identified and classified into 6 families (PLC-β, γ, δ, ε, ζ and η) based on their biochemical properties. Although the expression of PLC isoforms is tissue-specific, concomitant expression of different PLC has been reported, suggesting that PLC family is involved in multiple cellular functions. Despite their critical role, the PLC isoforms expressed in native endothelial cells (ECs) remains undetermined. A conventional PCR approach was initially used to elucidate the mRNA expression pattern of PLC isoforms in 3 distinct murine vascular beds: mesenteric (MA), pulmonary (PA) and middle cerebral arteries (MCA). mRNA encoding for most PLC isoforms was detected in MA, MCA and PA with the exception of η2 and β2 (only expressed in PA), δ4 (only expressed in MCA), η1 (expressed in all but MA) and ζ (not detected in any vascular beds tested). The endothelial-specific PLC expression was then sought in freshly isolated ECs. Interestingly, the PLC expression profile appears to differ across the investigated arterial beds. While mRNA for 8 of the 13 PLC isoforms was detected in ECs from MA, two additional PLC isoforms were detected in ECs from PA and MCA. Co-expression of multiple PLC isoforms in ECs suggests an elaborate network of signalling pathways: PLC isoforms may contribute to the complexity or diversity of signalling by their selective localization in cellular microdomains. However in situ immunofluorescence revealed a homogeneous distribution for all PLC isoforms probed (β3, γ2 and δ1) in intact endothelium. Although PLC isoforms play a crucial role in endothelial signal transduction, subcellular localization alone does not appear to be sufficient to determine the role of PLC in the signalling microdomains found in the native endothelium.
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Affiliation(s)
- Delphine M. Béziau
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Molecular and Integrative Physiology, Université de Montréal, Montreal, Qc, Canada
| | - Fanny Toussaint
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Molecular and Integrative Physiology, Université de Montréal, Montreal, Qc, Canada
| | | | - Nour R. Dayeh
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Medicine, Université de Montréal, Montreal, Qc, Canada
| | - Chimène Charbel
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Qc, Canada
| | - Jean-Claude Tardif
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Medicine, Université de Montréal, Montreal, Qc, Canada
| | - Jocelyn Dupuis
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Medicine, Université de Montréal, Montreal, Qc, Canada
| | - Jonathan Ledoux
- Research Center, Montreal Heart Institute, Montreal, Qc, Canada
- Department of Molecular and Integrative Physiology, Université de Montréal, Montreal, Qc, Canada
- Department of Pharmacology, Université de Montréal, Montreal, Qc, Canada
- Department of Medicine, Université de Montréal, Montreal, Qc, Canada
- * E-mail:
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84
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Abstract
Intrarenal autoregulatory mechanisms maintain renal blood flow (RBF) and glomerular filtration rate (GFR) independent of renal perfusion pressure (RPP) over a defined range (80-180 mmHg). Such autoregulation is mediated largely by the myogenic and the macula densa-tubuloglomerular feedback (MD-TGF) responses that regulate preglomerular vasomotor tone primarily of the afferent arteriole. Differences in response times allow separation of these mechanisms in the time and frequency domains. Mechanotransduction initiating the myogenic response requires a sensing mechanism activated by stretch of vascular smooth muscle cells (VSMCs) and coupled to intracellular signaling pathways eliciting plasma membrane depolarization and a rise in cytosolic free calcium concentration ([Ca(2+)]i). Proposed mechanosensors include epithelial sodium channels (ENaC), integrins, and/or transient receptor potential (TRP) channels. Increased [Ca(2+)]i occurs predominantly by Ca(2+) influx through L-type voltage-operated Ca(2+) channels (VOCC). Increased [Ca(2+)]i activates inositol trisphosphate receptors (IP3R) and ryanodine receptors (RyR) to mobilize Ca(2+) from sarcoplasmic reticular stores. Myogenic vasoconstriction is sustained by increased Ca(2+) sensitivity, mediated by protein kinase C and Rho/Rho-kinase that favors a positive balance between myosin light-chain kinase and phosphatase. Increased RPP activates MD-TGF by transducing a signal of epithelial MD salt reabsorption to adjust afferent arteriolar vasoconstriction. A combination of vascular and tubular mechanisms, novel to the kidney, provides for high autoregulatory efficiency that maintains RBF and GFR, stabilizes sodium excretion, and buffers transmission of RPP to sensitive glomerular capillaries, thereby protecting against hypertensive barotrauma. A unique aspect of the myogenic response in the renal vasculature is modulation of its strength and speed by the MD-TGF and by a connecting tubule glomerular feedback (CT-GF) mechanism. Reactive oxygen species and nitric oxide are modulators of myogenic and MD-TGF mechanisms. Attenuated renal autoregulation contributes to renal damage in many, but not all, models of renal, diabetic, and hypertensive diseases. This review provides a summary of our current knowledge regarding underlying mechanisms enabling renal autoregulation in health and disease and methods used for its study.
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Affiliation(s)
- Mattias Carlström
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Christopher S Wilcox
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - William J Arendshorst
- Department of Medicine, Division of Nephrology and Hypertension and Hypertension, Kidney and Vascular Research Center, Georgetown University, Washington, District of Columbia; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden; and Department of Cell Biology and Physiology, UNC Kidney Center, and McAllister Heart Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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85
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Longden TA, Nelson MT. Vascular inward rectifier K+ channels as external K+ sensors in the control of cerebral blood flow. Microcirculation 2015; 22:183-96. [PMID: 25641345 PMCID: PMC4404517 DOI: 10.1111/micc.12190] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 01/16/2015] [Indexed: 12/25/2022]
Abstract
For decades it has been known that external K(+) ions are rapid and potent vasodilators that increase CBF. Recent studies have implicated the local release of K(+) from astrocytic endfeet-which encase the entirety of the parenchymal vasculature-in the dynamic regulation of local CBF during NVC. It has been proposed that the activation of KIR channels in the vascular wall by external K(+) is a central component of these hyperemic responses; however, a number of significant gaps in our knowledge remain. Here, we explore the concept that vascular KIR channels are the major extracellular K(+) sensors in the control of CBF. We propose that K(+) is an ideal mediator of NVC, and discuss KIR channels as effectors that produce rapid hyperpolarization and robust vasodilation of cerebral arterioles. We provide evidence that KIR channels, of the KIR 2 subtype in particular, are present in both the endothelial and SM cells of parenchymal arterioles and propose that this dual positioning of KIR 2 channels increases the robustness of the vasodilation to external K(+), enables the endothelium to be actively engaged in NVC, and permits electrical signaling through the endothelial syncytium to promote upstream vasodilation to modulate CBF.
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Affiliation(s)
- Thomas A Longden
- Department of Pharmacology, College of Medicine, University of Vermont, Burlington, Vermont, USA
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86
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Yue Z, Xie J, Yu AS, Stock J, Du J, Yue L. Role of TRP channels in the cardiovascular system. Am J Physiol Heart Circ Physiol 2015; 308:H157-82. [PMID: 25416190 PMCID: PMC4312948 DOI: 10.1152/ajpheart.00457.2014] [Citation(s) in RCA: 126] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 11/14/2014] [Indexed: 12/12/2022]
Abstract
The transient receptor potential (TRP) superfamily consists of a large number of nonselective cation channels with variable degree of Ca(2+)-permeability. The 28 mammalian TRP channel proteins can be grouped into six subfamilies: canonical, vanilloid, melastatin, ankyrin, polycystic, and mucolipin TRPs. The majority of these TRP channels are expressed in different cell types including both excitable and nonexcitable cells of the cardiovascular system. Unlike voltage-gated ion channels, TRP channels do not have a typical voltage sensor, but instead can sense a variety of other stimuli including pressure, shear stress, mechanical stretch, oxidative stress, lipid environment alterations, hypertrophic signals, and inflammation products. By integrating multiple stimuli and transducing their activity to downstream cellular signal pathways via Ca(2+) entry and/or membrane depolarization, TRP channels play an essential role in regulating fundamental cell functions such as contraction, relaxation, proliferation, differentiation, and cell death. With the use of targeted deletion and transgenic mouse models, recent studies have revealed that TRP channels are involved in numerous cellular functions and play an important role in the pathophysiology of many diseases in the cardiovascular system. Moreover, several TRP channels are involved in inherited diseases of the cardiovascular system. This review presents an overview of current knowledge concerning the physiological functions of TRP channels in the cardiovascular system and their contributions to cardiovascular diseases. Ultimately, TRP channels may become potential therapeutic targets for cardiovascular diseases.
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Affiliation(s)
- Zhichao Yue
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Jia Xie
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Albert S Yu
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Jonathan Stock
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Jianyang Du
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
| | - Lixia Yue
- Calhoun Cardiology Center, Department of Cell Biology, University of Connecticut Health Center, Farmington, Connecticut
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87
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Abd-Elrahman KS, Walsh MP, Cole WC. Abnormal Rho-associated kinase activity contributes to the dysfunctional myogenic response of cerebral arteries in type 2 diabetes. Can J Physiol Pharmacol 2015; 93:177-84. [PMID: 25660561 DOI: 10.1139/cjpp-2014-0437] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The structural and functional integrity of the brain, and therefore, cognition, are critically dependent on the appropriate control of blood flow within the cerebral circulation. Inadequate flow leads to ischemia, whereas excessive flow causes small vessel rupture and (or) blood-brain-barrier disruption. Cerebral blood flow is controlled through the interplay of several physiological mechanisms that regulate the contractile state of vascular smooth muscle cells (VSMCs) within the walls of cerebral resistance arteries and arterioles. The myogenic response of cerebral VSMCs is a key mechanism that is responsible for maintaining constant blood flow during variations in systemic pressure, i.e., flow autoregulation. Inappropriate myogenic control of cerebral blood flow is associated with, and prognostic of, neurological deterioration and poor outcome in patients with several conditions, including type 2 diabetes. Here, we review recent advances in our understanding of the role of inappropriate Rho-associated kinase activity as a cause of impaired myogenic regulation of cerebral arterial diameter in type 2 diabetes.
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Affiliation(s)
- Khaled S Abd-Elrahman
- The Smooth Muscle Research Group, Libin Cardiovascular Institute, Hotchkiss Brain Institute, and the Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, AB T2N 4N1, Canada
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88
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Sullivan MN, Gonzales AL, Pires PW, Bruhl A, Leo MD, Li W, Oulidi A, Boop FA, Feng Y, Jaggar JH, Welsh DG, Earley S. Localized TRPA1 channel Ca2+ signals stimulated by reactive oxygen species promote cerebral artery dilation. Sci Signal 2015; 8:ra2. [PMID: 25564678 DOI: 10.1126/scisignal.2005659] [Citation(s) in RCA: 129] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Reactive oxygen species (ROS) can have divergent effects in cerebral and peripheral circulations. We found that Ca(2+)-permeable transient receptor potential ankyrin 1 (TRPA1) channels were present and colocalized with NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase 2 (NOX2), a major source of ROS, in the endothelium of cerebral arteries but not in other vascular beds. We recorded and characterized ROS-triggered Ca(2+) signals representing Ca(2+) influx through single TRPA1 channels, which we called "TRPA1 sparklets." TRPA1 sparklet activity was low under basal conditions but was stimulated by NOX-generated ROS. Ca(2+) entry during a single TRPA1 sparklet was twice that of a TRPV4 sparklet and ~200 times that of an L-type Ca(2+) channel sparklet. TRPA1 sparklets representing the simultaneous opening of two TRPA1 channels were more common in endothelial cells than in human embryonic kidney (HEK) 293 cells expressing TRPA1. The NOX-induced TRPA1 sparklets activated intermediate-conductance, Ca(2+)-sensitive K(+) channels, resulting in smooth muscle hyperpolarization and vasodilation. NOX-induced activation of TRPA1 sparklets and vasodilation required generation of hydrogen peroxide and lipid-peroxidizing hydroxyl radicals as intermediates. 4-Hydroxy-nonenal, a metabolite of lipid peroxidation, also increased TRPA1 sparklet frequency and dilated cerebral arteries. These data suggest that in the cerebral circulation, lipid peroxidation metabolites generated by ROS activate Ca(2+) influx through TRPA1 channels in the endothelium of cerebral arteries to cause dilation.
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Affiliation(s)
- Michelle N Sullivan
- Vascular Physiology Research Group, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Albert L Gonzales
- Department of Pharmacology, University of Vermont School of Medicine, Burlington, VT 05405, USA
| | - Paulo W Pires
- Department of Pharmacology, University of Nevada School of Medicine, Reno, NV 89557-0318, USA
| | - Allison Bruhl
- Vascular Physiology Research Group, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - M Dennis Leo
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Wencheng Li
- Vascular Physiology Research Group, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Agathe Oulidi
- Department of Pharmacology, University of Nevada School of Medicine, Reno, NV 89557-0318, USA
| | - Frederick A Boop
- Department of Neurosurgery, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Yumei Feng
- Vascular Physiology Research Group, Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Jonathan H Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Donald G Welsh
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Scott Earley
- Department of Pharmacology, University of Nevada School of Medicine, Reno, NV 89557-0318, USA.
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89
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MacKay CE, Knock GA. Control of vascular smooth muscle function by Src-family kinases and reactive oxygen species in health and disease. J Physiol 2014; 593:3815-28. [PMID: 25384773 DOI: 10.1113/jphysiol.2014.285304] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 10/22/2014] [Indexed: 12/13/2022] Open
Abstract
Reactive oxygen species (ROS) are now recognised as second messenger molecules that regulate cellular function by reversibly oxidising specific amino acid residues of key target proteins. Amongst these are the Src-family kinases (SrcFKs), a multi-functional group of non-receptor tyrosine kinases highly expressed in vascular smooth muscle (VSM). In this review we examine the evidence supporting a role for ROS-induced SrcFK activity in normal VSM contractile function and in vascular remodelling in cardiovascular disease. VSM contractile responses to G-protein-coupled receptor stimulation, as well as hypoxia in pulmonary artery, are shown to be dependent on both ROS and SrcFK activity. Specific phosphorylation targets are identified amongst those that alter intracellular Ca(2+) concentration, including transient receptor potential channels, voltage-gated Ca(2+) channels and various types of K(+) channels, as well as amongst those that regulate actin cytoskeleton dynamics and myosin phosphatase activity, including focal adhesion kinase, protein tyrosine kinase-2, Janus kinase, other focal adhesion-associated proteins, and Rho guanine nucleotide exchange factors. We also examine a growing weight of evidence in favour of a key role for SrcFKs in multiple pro-proliferative and anti-apoptotic signalling pathways relating to oxidative stress and vascular remodelling, with a particular focus on pulmonary hypertension, including growth-factor receptor transactivation and downstream signalling, hypoxia-inducible factors, positive feedback between SrcFK and STAT3 signalling and positive feedback between SrcFK and NADPH oxidase dependent ROS production. We also discuss evidence for and against the potential therapeutic targeting of SrcFKs in the treatment of pulmonary hypertension.
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Affiliation(s)
- Charles E MacKay
- Asthma, Allergy and Lung Biology, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Greg A Knock
- Asthma, Allergy and Lung Biology, Faculty of Life Sciences and Medicine, King's College London, London, UK
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90
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Earley S, VanHook AM. Science Signaling
Podcast: 3 June 2014. Sci Signal 2014. [DOI: 10.1126/scisignal.2005480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A pressure-sensitive signaling pathway maintains constant blood flow to the brain.
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Affiliation(s)
- Scott Earley
- Department of Pharmacology, University of Nevada School of Medicine, Reno, NV, 89557–0318 USA
| | - Annalisa M. VanHook
- Web Editor, Science Signaling, American Association for the Advancement of Science, 1200 New York Avenue NW, Washington, DC, 20005, USA
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