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May the remodeling of the Ca²⁺ toolkit in endothelial progenitor cells derived from cancer patients suggest alternative targets for anti-angiogenic treatment? BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:1958-73. [PMID: 25447551 DOI: 10.1016/j.bbamcr.2014.10.024] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 10/16/2014] [Accepted: 10/28/2014] [Indexed: 01/10/2023]
Abstract
Endothelial progenitor cells (EPCs) may be recruited from bone marrow to sustain the metastatic switch in a number of solid cancers, including breast cancer (BC) and renal cellular carcinoma (RCC). Preventing EPC mobilization causes tumor shrinkage. Novel anti-angiogenic treatments have been introduced in therapy to inhibit VEGFR-2 signaling; unfortunately, these drugs blocked tumor angiogenesis in pre-clinical murine models, but resulted far less effective in human patients. Understanding the molecular mechanisms driving EPC proliferation and tubulogenesis in cancer patients could outline novel targets for alternative anti-angiogenic treatments. Store-operated Ca²⁺ entry (SOCE) regulates the growth of human EPCs, and it is mediated by the interaction between the endoplasmic reticulum Ca²⁺-sensor, Stim1, and the plasmalemmal Ca²⁺ channels, Orai1 and TRPC1. EPCs do not belong to the neoplastic clone: thus, unlike tumor endothelium and neoplastic cells, they should not remodel their Ca²⁺ toolkit in response to tumor microenvironment. However, our recent work demonstrated that EPCs isolated from naïve RCC patients (RCC-EPCs) undergo a dramatic remodeling of their Ca²⁺ toolkit by displaying a remarkable drop in the endoplasmic reticulum Ca²⁺ content, by down-regulating the expression of inositol-1,4,5-receptors (InsP3Rs), and by up-regulating Stim1, Orai1 and TRPC1. Moreover, EPCs are dramatically less sensitive to VEGF stimulation both in terms of Ca²⁺ signaling and of gene expression when isolated from tumor patients. Conversely, the pharmacological abolition of SOCE suppresses proliferation in these cells. These results question the suitability of VEGFR-2 as a therapeutically relevant target for anti-angiogenic treatments and hint at Orai1 and TRPC1 as more promising alternatives. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.
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Sanokawa-Akakura R, Ostrakhovitch EA, Akakura S, Goodwin S, Tabibzadeh S. A H2S-Nampt dependent energetic circuit is critical to survival and cytoprotection from damage in cancer cells. PLoS One 2014; 9:e108537. [PMID: 25248148 PMCID: PMC4172766 DOI: 10.1371/journal.pone.0108537] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/27/2014] [Indexed: 11/18/2022] Open
Abstract
We recently demonstrated that cancer cells that recover from damage exhibit increased aerobic glycolysis, however, the molecular mechanism by which cancer cells survive the damage and show increased aerobic glycolysis remains unknown. Here, we demonstrate that diverse cancer cells that survive hypoxic or oxidative damage show rapid cell proliferation, and develop tolerance to damage associated with increased production of hydrogen sulfide (H2S) which drives up-regulation of nicotinamide phosphoribosyltransferase (Nampt). Consistent with existence of a H2S-Nampt energetic circuit, in damage recovered cancer cells, H2S, Nampt and ATP production exhibit a significant correlation. Moreover, the treatment of cancer cells with H2S donor, NaHS, coordinately increases Nampt and ATP levels, and protects cells from drug induced damage. Inhibition of cystathionine beta synthase (CBS) or cystathionase (CTH), enzymes which drive generation of H2S, decreases Nampt production while suppression of Nampt pathway by FK866, decreases H2S and ATP levels. Damage recovered cells isolated from tumors grown subcutaneously in athymic mice also show increased production of H2S, Nampt and ATP levels, associated with increased glycolysis and rapid proliferation. Together, these data show that upon recovery from potential lethal damage, H2S-Nampt directs energy expenditure and aerobic glycolysis in cancer cells, leads to their exponential growth, and causes a high degree of tolerance to damage. Identification of H2S-Nampt as a pathway responsible for induction of damage tolerance in cancer cells may underlie resistance to therapy and offers the opportunity to target this pathway as a means in treatment of cancer.
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Affiliation(s)
- Reiko Sanokawa-Akakura
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Elena A. Ostrakhovitch
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Shin Akakura
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
| | - Scott Goodwin
- Dept of Radiological Sciences, University of California Irvine, Irvine, California, United States of America
| | - Siamak Tabibzadeh
- Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, California, United States of America
- Dept of Radiological Sciences, University of California Irvine, Irvine, California, United States of America
- * E-mail:
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Abstract
Hydrogen sulfide (H2S) has emerged as a key regulator of cardiovascular function. This gasotransmitter is produced in the vasculature and is involved in numerous processes that promote vascular homeostasis, including vasodilation and endothelial cell proliferation. Although H2S plays a role under physiological conditions, it has become clear in recent years that hypoxia modulates the production and action of H2S. Furthermore, there is growing evidence that H2S is cytoprotective in the face of hypoxic insults. This review focuses on the synthesis and signaling of H2S in hypoxic conditions in the vasculature, and highlights recent studies providing evidence that H2S is a potential therapy for preventing tissue damage in hypoxic conditions.
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Affiliation(s)
- Jessica M Osmond
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
| | - Nancy L Kanagy
- Vascular Physiology Group, Department of Cell Biology and Physiology, University of New Mexico Health Sciences Center, Albuquerque, NM, USA
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54
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Cheng RYS, Basudhar D, Ridnour LA, Heinecke JL, Kesarwala AH, Glynn S, Switzer CH, Ambs S, Miranda KM, Wink DA. Gene expression profiles of NO- and HNO-donor treated breast cancer cells: insights into tumor response and resistance pathways. Nitric Oxide 2014; 43:17-28. [PMID: 25153034 DOI: 10.1016/j.niox.2014.08.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 08/07/2014] [Accepted: 08/14/2014] [Indexed: 01/27/2023]
Abstract
Nitric oxide (NO) synthase 2 (NOS2), a major inflammatory protein, modulates disease progression via NO in a number of pathologies, including cancer. The role of NOS2-derived NO is not only flux-dependent, which is higher in mouse vs human cells, but also varies based on spatial and temporal distribution both within tumor cells and in the tumor microenvironment. NO donors have been utilized to mimic NO flux conditions and to investigate the effects of varied NO concentrations. As a wide range of effects mediated by NO and other nitrogen oxides such as nitroxyl (HNO) have been elucidated, multiple NO- and HNO-releasing compounds have been developed as potential therapeutics, including as tumor modulators. One of the challenges is to determine differences in biomarker expression from extracellular vs intracellular generation of NO or HNO. Taking advantage of new NO and HNO releasing agents, we have characterized the gene expression profile of estrogen receptor-negative human breast cancer (MDA-MB-231) cells following exposure to aspirin, the NO donor DEA/NO, the HNO donor IPA/NO andtheir intracellularly-activated prodrug conjugates DEA/NO-aspirin and IPA/NO-aspirin. Comparison of the gene expression profiles demonstrated that several genes were uniquely expressed with respect to NO or HNO, such as miR-21, HSP70, cystathionine γ-lyase and IL24. These findings provide insight into targets and pathways that could be therapeutically exploited by the redox related species NO and HNO.
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Affiliation(s)
- Robert Y S Cheng
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA.
| | - Debashree Basudhar
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA; Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - Lisa A Ridnour
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Julie L Heinecke
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Aparna H Kesarwala
- Radiation Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | | | - Christopher H Switzer
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Stefan Ambs
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Katrina M Miranda
- Department of Chemistry, University of Arizona, Tucson, AZ 85721, USA
| | - David A Wink
- Radiation Biology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
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Potenza DM, Guerra G, Avanzato D, Poletto V, Pareek S, Guido D, Gallanti A, Rosti V, Munaron L, Tanzi F, Moccia F. Hydrogen sulphide triggers VEGF-induced intracellular Ca²⁺ signals in human endothelial cells but not in their immature progenitors. Cell Calcium 2014; 56:225-34. [PMID: 25113159 DOI: 10.1016/j.ceca.2014.07.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Revised: 07/09/2014] [Accepted: 07/18/2014] [Indexed: 10/25/2022]
Abstract
Hydrogen sulphide (H2S) is a newly discovered gasotransmitter that regulates multiple steps in VEGF-induced angiogenesis. An increase in intracellular Ca(2+) concentration ([Ca(2+)]i) is central to endothelial proliferation and may be triggered by both VEGF and H2S. Albeit VEGFR-2 might serve as H2S receptor, the mechanistic relationship between VEGF- and H2S-induced Ca(2+) signals in endothelial cells is unclear. The present study aimed at assessing whether and how NaHS, a widely employed H2S donor, stimulates pro-angiogenic Ca(2+) signals in Ea.hy926 cells, a suitable surrogate for mature endothelial cells, and human endothelial progenitor cells (EPCs). We found that NaHS induced a dose-dependent increase in [Ca(2+)]i in Ea.hy926 cells. NaHS-induced Ca(2+) signals in Ea.hy926 cells did not require extracellular Ca(2+) entry, while they were inhibited upon pharmacological blockade of the phospholipase C/inositol-1,4,5-trisphosphate (InsP3) signalling pathway. Moreover, the Ca(2+) response to NaHS was prevented by genistein, but not by SU5416, which selectively inhibits VEGFR-2. However, VEGF-induced Ca(2+) signals were suppressed by dl-propargylglycine (PAG), which blocks the H2S-producing enzyme, cystathionine γ-lyase. Consistent with these data, VEGF-induced proliferation and migration were inhibited by PAG in Ea.hy926 cells, albeit NaHS alone did not influence these processes. Conversely, NaHS elevated [Ca(2+)]i only in a modest fraction of circulating EPCs, whereas neither VEGF-induced Ca(2+) oscillations nor VEGF-dependent proliferation were affected by PAG. Therefore, H2S-evoked elevation in [Ca(2+)]i is essential to trigger the pro-angiogenic Ca(2+) response to VEGF in mature endothelial cells, but not in their immature progenitors.
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Affiliation(s)
- Duilio Michele Potenza
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Germano Guerra
- Department of Health Sciences, University of Molise, Via F. De Santis, 86100 Campobasso, Italy
| | - Daniele Avanzato
- Department of Life Sciences and Systems Biology, Centre for Nanostructured Interfaces and Surfaces, Centre for Complex Systems in Molecular Biology and Medicine, University of Torino, 10123 Torino, Italy
| | - Valentina Poletto
- Center for the Study of Myelofibrosis, Research Laboratory of Biotechnology, IRCCS Policlinico San Matteo Foundation, Piazzale Golgi 19, 27100 Pavia, Italy
| | - Sumedha Pareek
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Daniele Guido
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Angelo Gallanti
- Department of Molecular Medicine, University of Pavia, Via Taramelli 10, 27100 Pavia, Italy
| | - Vittorio Rosti
- Center for the Study of Myelofibrosis, Research Laboratory of Biotechnology, IRCCS Policlinico San Matteo Foundation, Piazzale Golgi 19, 27100 Pavia, Italy
| | - Luca Munaron
- Department of Life Sciences and Systems Biology, Centre for Nanostructured Interfaces and Surfaces, Centre for Complex Systems in Molecular Biology and Medicine, University of Torino, 10123 Torino, Italy
| | - Franco Tanzi
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
| | - Francesco Moccia
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Forlanini 6, 27100 Pavia, Italy.
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Fiorio Pla A, Munaron L. Functional properties of ion channels and transporters in tumour vascularization. Philos Trans R Soc Lond B Biol Sci 2014; 369:20130103. [PMID: 24493751 DOI: 10.1098/rstb.2013.0103] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Vascularization is crucial for solid tumour growth and invasion, providing metabolic support and sustaining metastatic dissemination. It is now accepted that ion channels and transporters play a significant role in driving the cancer growth at all stages. They may represent novel therapeutic, diagnostic and prognostic targets for anti-cancer therapies. On the other hand, although the expression and role of ion channels and transporters in the vascular endothelium is well recognized and subject of recent reviews, only recently has their involvement in tumour vascularization been recognized. Here, we review the current literature on ion channels and transporters directly involved in the angiogenic process. Particular interest will be focused on tumour angiogenesis in vivo as well as in the different steps that drive this process in vitro, such as endothelial cell proliferation, migration, adhesion and tubulogenesis. Moreover, we compare the 'transportome' system of tumour vascular network with the physiological one.
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Affiliation(s)
- Alessandra Fiorio Pla
- Department of Life Sciences and Systems Biology, Center for Complex Systems in Molecular Biology and Medicine (SysBioM), Nanostructured Interfaces and Surfaces Centre of Excellence (NIS), University of Torino, , Via Accademia Albertina 13, Torino 10123, Italy
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57
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Berra-Romani R, Avelino-Cruz JE, Raqeeb A, Della Corte A, Cinelli M, Montagnani S, Guerra G, Moccia F, Tanzi F. Ca²⁺-dependent nitric oxide release in the injured endothelium of excised rat aorta: a promising mechanism applying in vascular prosthetic devices in aging patients. BMC Surg 2013; 13 Suppl 2:S40. [PMID: 24266895 PMCID: PMC3851245 DOI: 10.1186/1471-2482-13-s2-s40] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background Nitric oxide is key to endothelial regeneration, but it is still unknown whether endothelial cell (EC) loss results in an increase in NO levels at the wound edge. We have already shown that endothelial damage induces a long-lasting Ca2+ entry into surviving cells though connexin hemichannels (CxHcs) uncoupled from their counterparts on ruptured cells. The physiological outcome of injury-induced Ca2+ inflow is, however, unknown. Methods In this study, we sought to determine whether and how endothelial scraping induces NO production (NOP) in the endothelium of excised rat aorta by exploiting the NO-sensitive fluorochrome, DAF-FM diacetate and the Ca2+-sensitive fluorescent dye, Fura-2/AM. Results We demonstrated that injury-induced NOP at the lesion site is prevented in presence of the endothelial NO synthase inhibitor, L-NAME, and in absence of extracellular Ca2+. Unlike ATP-dependent NO liberation, the NO response to injury is insensitive to BTP-2, which selectively blocks store-operated Ca2+ inflow. However, injury-induced NOP is significantly reduced by classic gap junction blockers, and by connexin mimetic peptides specifically targeting Cx37Hcs, Cx40HCs, and Cx43Hcs. Moreover, disruption of caveolar integrity prevents injury-elicited NO signaling, but not the accompanying Ca2+ response. Conclusions The data presented provide the first evidence that endothelial scraping stimulates NO synthesis at the wound edge, which might both exert an immediate anti-thrombotic and anti-inflammatory action and promote the subsequent re-endothelialization.
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Tumor-derived hydrogen sulfide, produced by cystathionine-β-synthase, stimulates bioenergetics, cell proliferation, and angiogenesis in colon cancer. Proc Natl Acad Sci U S A 2013; 110:12474-9. [PMID: 23836652 DOI: 10.1073/pnas.1306241110] [Citation(s) in RCA: 517] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The physiological functions of hydrogen sulfide (H2S) include vasorelaxation, stimulation of cellular bioenergetics, and promotion of angiogenesis. Analysis of human colon cancer biopsies and patient-matched normal margin mucosa revealed the selective up-regulation of the H2S-producing enzyme cystathionine-β-synthase (CBS) in colon cancer, resulting in an increased rate of H2S production. Similarly, colon cancer-derived epithelial cell lines (HCT116, HT-29, LoVo) exhibited selective CBS up-regulation and increased H2S production, compared with the nonmalignant colonic mucosa cells, NCM356. CBS localized to the cytosol, as well as the mitochondrial outer membrane. ShRNA-mediated silencing of CBS or its pharmacological inhibition with aminooxyacetic acid reduced HCT116 cell proliferation, migration, and invasion; reduced endothelial cell migration in tumor/endothelial cell cocultures; and suppressed mitochondrial function (oxygen consumption, ATP turnover, and respiratory reserve capacity), as well as glycolysis. Treatment of nude mice with aminooxyacetic acid attenuated the growth of patient-derived colon cancer xenografts and reduced tumor blood flow. Similarly, CBS silencing of the tumor cells decreased xenograft growth and suppressed neovessel density, suggesting a role for endogenous H2S in tumor angiogenesis. In contrast to CBS, silencing of cystathionine-γ-lyase (the expression of which was unchanged in colon cancer) did not affect tumor growth or bioenergetics. In conclusion, H2S produced from CBS serves to (i) maintain colon cancer cellular bioenergetics, thereby supporting tumor growth and proliferation, and (ii) promote angiogenesis and vasorelaxation, consequently providing the tumor with blood and nutritients. The current findings identify CBS-derived H2S as a tumor growth factor and anticancer drug target.
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59
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Dragoni S, Laforenza U, Bonetti E, Lodola F, Bottino C, Guerra G, Borghesi A, Stronati M, Rosti V, Tanzi F, Moccia F. Canonical transient receptor potential 3 channel triggers vascular endothelial growth factor-induced intracellular Ca2+ oscillations in endothelial progenitor cells isolated from umbilical cord blood. Stem Cells Dev 2013; 22:2561-80. [PMID: 23682725 DOI: 10.1089/scd.2013.0032] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Endothelial colony-forming cells (ECFCs) are the only endothelial progenitor cells (EPCs) that are capable of acquiring a mature endothelial phenotype. ECFCs are mainly mobilized from bone marrow to promote vascularization and represent a promising tool for cell-based therapy of severe ischemic diseases. Vascular endothelial growth factor (VEGF) stimulates the proliferation of peripheral blood-derived ECFCs (PB-ECFCs) through oscillations in intracellular Ca(2+) concentration ([Ca(2+)]i). VEGF-induced Ca(2+) spikes are driven by the interplay between inositol-1,4,5-trisphosphate (InsP3)-dependent Ca(2+) release and store-operated Ca(2+) entry (SOCE). The therapeutic potential of umbilical cord blood-derived ECFCs (UCB-ECFCs) has also been shown in recent studies. However, VEGF-induced proliferation of UCB-ECFCs is faster compared with their peripheral counterpart. Unlike PB-ECFCs, UCB-ECFCs express canonical transient receptor potential channel 3 (TRPC3) that mediates diacylglycerol-dependent Ca(2+) entry. The present study aimed at investigating whether the higher proliferative potential of UCB-ECFCs was associated to any difference in the molecular underpinnings of their Ca(2+) response to VEGF. We found that VEGF induces oscillations in [Ca(2+)]i that are patterned by the interaction between InsP3-dependent Ca(2+) release and SOCE. Unlike PB-ECFCs, VEGF-evoked Ca(2+) oscillations do not arise in the absence of extracellular Ca(2+) entry and after pharmacological (with Pyr3 and flufenamic acid) and genetic (by employing selective small interference RNA) suppression of TRPC3. VEGF-induced UCB-ECFC proliferation is abrogated on inhibition of the intracellular Ca(2+) spikes. Therefore, the Ca(2+) response to VEGF in UCB-ECFCs is shaped by a different Ca(2+) machinery as compared with PB-ECFCs, and TRPC3 stands out as a promising target in EPC-based treatment of ischemic pathologies.
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Affiliation(s)
- Silvia Dragoni
- 1 Department of Biology and Biotechnology "Lazzaro Spallanzani,", University of Pavia , Pavia, Italy
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Jackson-Weaver O, Osmond JM, Riddle MA, Naik JS, Gonzalez Bosc LV, Walker BR, Kanagy NL. Hydrogen sulfide dilates rat mesenteric arteries by activating endothelial large-conductance Ca²⁺-activated K⁺ channels and smooth muscle Ca²⁺ sparks. Am J Physiol Heart Circ Physiol 2013; 304:H1446-54. [PMID: 23525712 DOI: 10.1152/ajpheart.00506.2012] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We have previously shown that hydrogen sulfide (H₂S) reduces myogenic tone and causes relaxation of phenylephrine (PE)-constricted mesenteric arteries. This effect of H₂S to cause vasodilation and vascular smooth muscle cell (VSMC) hyperpolarization was mediated by large-conductance Ca(2+)-activated potassium channels (BKCa). Ca(2+) sparks are ryanodine receptor (RyR)-mediated Ca(2+)-release events that activate BKCa channels in VSMCs to cause membrane hyperpolarization and vasodilation. We hypothesized that H₂S activates Ca(2+) sparks in small mesenteric arteries. Ca(2+) sparks were measured using confocal microscopy in rat mesenteric arteries loaded with the Ca(2+) indicator fluo-4. VSMC membrane potential (Em) was measured in isolated arteries using sharp microelectrodes. In PE-constricted arteries, the H₂S donor NaHS caused vasodilation that was inhibited by ryanodine (RyR blocker), abluminal or luminal iberiotoxin (IbTx, BKCa blocker), endothelial cell (EC) disruption, and sulfaphenazole [cytochrome P-450 2C (Cyp2C) inhibitor]. The H₂S donor NaHS (10 μmol/l) increased Ca(2+) sparks but only in the presence of intact EC and this was blocked by sulfaphenazole or luminal IbTx. Inhibiting cystathionine γ-lyase (CSE)-derived H2S with β-cyano-l-alanine (BCA) also reduced VSMC Ca(2+) spark frequency in mesenteric arteries, as did EC disruption. However, excess CSE substrate homocysteine did not affect spark activity. NaHS hyperpolarized VSMC Em in PE-depolarized mesenteric arteries with intact EC and also hyperpolarized EC Em in arteries cut open to expose the lumen. This hyperpolarization was prevented by ryanodine, sulfaphenazole, and abluminal or luminal IbTx. BCA reduced IbTx-sensitive K(+) currents in freshly dispersed mesenteric ECs. These results suggest that H₂S increases Ca(2+) spark activity in mesenteric artery VSMC through activation of endothelial BKCa channels and Cyp2C, a novel vasodilatory pathway for this emerging signaling molecule.
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Affiliation(s)
- Olan Jackson-Weaver
- Vascular Physiology Group, Department of Cell Biology and Physiology, School of Medicine, University of New Mexico, Albuquerque, NM 87131, USA
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61
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Munaron L, Avanzato D, Moccia F, Mancardi D. Hydrogen sulfide as a regulator of calcium channels. Cell Calcium 2013; 53:77-84. [DOI: 10.1016/j.ceca.2012.07.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 05/30/2012] [Accepted: 07/05/2012] [Indexed: 12/18/2022]
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Moccia F, Berra-Romani R, Tanzi F. Update on vascular endothelial Ca 2+ signalling: A tale of ion channels, pumps and transporters. World J Biol Chem 2012; 3:127-58. [PMID: 22905291 PMCID: PMC3421132 DOI: 10.4331/wjbc.v3.i7.127] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 07/04/2012] [Accepted: 07/11/2012] [Indexed: 02/05/2023] Open
Abstract
A monolayer of endothelial cells (ECs) lines the lumen of blood vessels and forms a multifunctional transducing organ that mediates a plethora of cardiovascular processes. The activation of ECs from as state of quiescence is, therefore, regarded among the early events leading to the onset and progression of potentially lethal diseases, such as hypertension, myocardial infarction, brain stroke, and tumor. Intracellular Ca2+ signals have long been know to play a central role in the complex network of signaling pathways regulating the endothelial functions. Notably, recent work has outlined how any change in the pattern of expression of endothelial channels, transporters and pumps involved in the modulation of intracellular Ca2+ levels may dramatically affect whole body homeostasis. Vascular ECs may react to both mechanical and chemical stimuli by generating a variety of intracellular Ca2+ signals, ranging from brief, localized Ca2+ pulses to prolonged Ca2+ oscillations engulfing the whole cytoplasm. The well-defined spatiotemporal profile of the subcellular Ca2+ signals elicited in ECs by specific extracellular inputs depends on the interaction between Ca2+ releasing channels, which are located both on the plasma membrane and in a number of intracellular organelles, and Ca2+ removing systems. The present article aims to summarize both the past and recent literature in the field to provide a clear-cut picture of our current knowledge on the molecular nature and the role played by the components of the Ca2+ machinery in vascular ECs under both physiological and pathological conditions.
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Affiliation(s)
- Francesco Moccia
- Francesco Moccia, Franco Tanzi, Department of Biology and Biotechnologies "Lazzaro Spallanzani", Laboratory of Physiology, University of Pavia, Via Forlanini 6, 27100 Pavia, Italy
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63
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Hydrogen sulfide and resolution of acute inflammation: A comparative study utilizing a novel fluorescent probe. Sci Rep 2012; 2:499. [PMID: 22787557 PMCID: PMC3391661 DOI: 10.1038/srep00499] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 06/25/2012] [Indexed: 01/28/2023] Open
Abstract
Hydrogen sulfide is an essential gasotransmitter associated with numerous pathologies. We assert that hydrogen sulfide plays an important role in regulating macrophage function in response to subsequent inflammatory stimuli, promoting clearance of leukocyte infiltrate and reducing TNF-α levels in vivo following zymosan-challenge. We describe two distinct methods of measuring leukocyte hydrogen sulfide synthesis; methylene blue formation following zinc acetate capture and a novel fluorescent sulfidefluor probe. Comparison of these methods, using pharmacological tools, revealed they were complimentary in vitro and in vivo. We demonstrate the application of sulfidefluor probe to spectrofluorimetry, flow cytometry and whole animal imaging, to monitor the regulation of hydrogen sulfide synthesis in vivo during dynamic inflammatory processes. Both methodologies revealed that granulocyte infiltration negatively affects hydrogen sulfide synthesis. Our report offers an insight into the profile of hydrogen sulfide synthesis during inflammation and highlight opportunities raised by the development of novel fluorescent hydrogen sulfide probes.
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64
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Munaron L, Scianna M. Multilevel complexity of calcium signaling: Modeling angiogenesis. World J Biol Chem 2012; 3:121-6. [PMID: 22905290 PMCID: PMC3421110 DOI: 10.4331/wjbc.v3.i6.121] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Revised: 05/11/2012] [Accepted: 05/18/2012] [Indexed: 02/05/2023] Open
Abstract
Intracellular calcium signaling is a universal, evolutionary conserved and versatile regulator of cell biochemistry. The complexity of calcium signaling and related cell machinery can be investigated by the use of experimental strategies, as well as by computational approaches. Vascular endothelium is a fascinating model to study the specific properties and roles of calcium signals at multiple biological levels. During the past 20 years, live cell imaging, patch clamp and other techniques have allowed us to detect and interfere with calcium signaling in endothelial cells (ECs), providing a huge amount of information on the regulation of vascularization (angiogenesis) in normal and tumoral tissues. These data range from the spatiotemporal dynamics of calcium within different cell microcompartments to those in entire multicellular and organized EC networks. Beside experimental strategies, in silico endothelial models, specifically designed for simulating calcium signaling, are contributing to our knowledge of vascular physiology and pathology. They help to investigate and predict the quantitative features of proangiogenic events moving through subcellular, cellular and supracellular levels. This review focuses on some recent developments of computational approaches for proangiogenic endothelial calcium signaling. In particular, we discuss the creation of hybrid simulation environments, which combine and integrate discrete Cellular Potts Models. They are able to capture the phenomenological mechanisms of cell morphological reorganization, migration, and intercellular adhesion, with single-cell spatiotemporal models, based on reaction-diffusion equations that describe the agonist-induced intracellular calcium events.
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Affiliation(s)
- Luca Munaron
- Luca Munaron, Department of Life Sciences and Systems Biology, Centre for Nanostructured Interfaces and Surfaces, Centre for Complex Systems in Molecular Biology and Medicine, University of Torino, 10123 Torino, Italy
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