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Wurtzel JGT, Lazar S, Askari S, Zhao X, Severa J, Ayombil F, Michael JV, Camire RM, McKenzie SE, Stalker TJ, Ma P, Goldfinger LE. Plasma growth factors maintain constitutive translation in platelets to regulate reactivity and thrombotic potential. Blood Adv 2024; 8:1550-1566. [PMID: 38163324 PMCID: PMC10982986 DOI: 10.1182/bloodadvances.2023011734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/14/2023] [Accepted: 11/30/2023] [Indexed: 01/03/2024] Open
Abstract
ABSTRACT Mechanisms of proteostasis in anucleate circulating platelets are unknown and may regulate platelet function. We investigated the hypothesis that plasma-borne growth factors/hormones (GFHs) maintain constitutive translation in circulating platelets to facilitate reactivity. Bio-orthogonal noncanonical amino acid tagging (BONCAT) coupled with liquid chromatography-tandem mass spectrometry analysis revealed constitutive translation of a broad-spectrum translatome in human platelets dependent upon plasma or GFH exposure, and in murine circulation. Freshly isolated platelets from plasma showed homeostatic activation of translation-initiation signaling pathways: phosphorylation of p38/ERK upstream kinases, essential intermediate MNK1/2, and effectors eIF4E/4E-BP1. Plasma starvation led to loss of pathway phosphorylation, but it was fully restored with 5-minute stimulation by plasma or GFHs. Cycloheximide or puromycin infusion suppressed ex vivo platelet GpIIb/IIIa activation and P-selectin exposure with low thrombin concentrations and low-to-saturating concentrations of adenosine 5'-diphosphate (ADP) or thromboxane analog but not convulxin. ADP-induced thromboxane generation was blunted by translation inhibition, and secondary-wave aggregation was inhibited in a thromboxane-dependent manner. Intravenously administered puromycin reduced injury-induced clot size in cremaster muscle arterioles, and delayed primary hemostasis after tail tip amputation but did not delay neither final hemostasis after subsequent rebleeds, nor final hemostasis after jugular vein puncture. In contrast, these mice were protected from injury-induced arterial thrombosis and thrombin-induced pulmonary thromboembolism (PE), and adoptive transfer of translation-inhibited platelets into untreated mice inhibited arterial thrombosis and PE. Thus, constitutive plasma GFH-driven translation regulates platelet G protein-coupled receptor reactivity to balance hemostasis and thrombotic potential.
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Affiliation(s)
- Jeremy G. T. Wurtzel
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Sophia Lazar
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Shayan Askari
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Xuefei Zhao
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Jenna Severa
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Francis Ayombil
- Division of Hematology and the Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA
| | - James V. Michael
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Rodney M. Camire
- Division of Hematology and the Raymond G. Perelman Center for Cellular and Molecular Therapeutics, The Children’s Hospital of Philadelphia, Philadelphia, PA
- Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Steven E. McKenzie
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Timothy J. Stalker
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Peisong Ma
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
| | - Lawrence E. Goldfinger
- Division of Hematology, Department of Medicine, Cardeza Foundation for Hematologic Research, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA
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Aid M, Stephenson KE, Collier ARY, Nkolola JP, Michael JV, McKenzie SE, Barouch DH. Activation of coagulation and proinflammatory pathways in thrombosis with thrombocytopenia syndrome and following COVID-19 vaccination. Nat Commun 2023; 14:6703. [PMID: 37872311 PMCID: PMC10593859 DOI: 10.1038/s41467-023-42559-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 10/16/2023] [Indexed: 10/25/2023] Open
Abstract
Thrombosis with thrombocytopenia syndrome (TTS) is a rare but potentially severe adverse event following immunization with adenovirus vector-based COVID-19 vaccines such as Ad26.COV2.S (Janssen) and ChAdOx1 (AstraZeneca). However, no case of TTS has been reported in over 1.5 million individuals who received a second immunization with Ad26.COV2.S in the United States. Here we utilize transcriptomic and proteomic profiling to compare individuals who receive two doses of Ad26.COV2.S with those vaccinated with BNT162b2 or mRNA-1273. Initial Ad26.COV2.S vaccination induces transient activation of platelet and coagulation and innate immune pathways that resolve by day 7; by contrast, patients with TTS show robust upregulation of these pathways on days 15-19 following initial Ad26.COV2.S vaccination. Meanwhile, a second immunization or a reduced initial dose of Ad26.COV2.S induces lower activation of these pathways than does the full initial dose. Our data suggest a role of coagulation and proinflammatory pathways in TTS pathogenesis, which may help optimize vaccination regimens to reduce TTS risk.
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Affiliation(s)
- Malika Aid
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Kathryn E Stephenson
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Ai-Ris Y Collier
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Joseph P Nkolola
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - James V Michael
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA, USA
| | - Steven E McKenzie
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA, USA
| | - Dan H Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University, Cambridge, MA, USA.
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3
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Renna SA, Zhao X, Kunapuli SP, Ma P, Holinstat M, Boxer MB, Maloney DJ, Michael JV, McKenzie SE. Novel Strategy to Combat the Procoagulant Phenotype in Heparin-Induced Thrombocytopenia Using 12-LOX Inhibition. Arterioscler Thromb Vasc Biol 2023; 43:1808-1817. [PMID: 37345522 DOI: 10.1161/atvbaha.123.319434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 06/13/2023] [Indexed: 06/23/2023]
Abstract
BACKGROUND Heparin-induced thrombocytopenia (HIT) is a major concern for all individuals that undergo cardiac bypass surgeries or require prolonged heparin exposure. HIT is a life- and limb-threatening adverse drug reaction with an immune response following the formation of ultra-large immune complexes that drive platelet activation through the receptor FcγRIIA. Thrombotic events remain high following the standard of care treatment with anticoagulants, while increasing risk of bleeding complications. This study sought to investigate a novel approach to treatment of HIT. Recent reports demonstrate increased procoagulant activity in HIT; however, these reports required analysis ex vivo, and relevance in vivo remains unclear. METHODS Using human and mouse model systems, we investigated the cooperativity of PARs (protease-activated receptors) and FcγRIIA in HIT. We challenged humanized FcγRIIA transgenic mice with or without endogenous mouse Par4 (denoted as IIA-Par4+/+ or IIA-Par4-/-, respectively) with a well-established model IgG immune complex (anti [α]-CD9). Furthermore, we assessed the procoagulant phenotype and efficacy to treat HIT utilizing inhibitor of 12-LOX (12[S]-lipoxygenase), VLX-1005, previously reported to decrease platelet activation downstream of FcγRIIA and PAR4, using the triple allele HIT mouse model. RESULTS IIA-Par4+/+ mice given αCD9 were severely thrombocytopenic, with extensive platelet-fibrin deposition in the lung. In contrast, IIA-Par4-/- mice had negligible thrombocytopenia or pulmonary platelet-fibrin thrombi. We observed that pharmacological inhibition of 12-LOX resulted in a significant reduction in both platelet procoagulant phenotype ex vivo, and thrombocytopenia and thrombosis in our humanized mouse model of HIT in vivo. CONCLUSIONS These data demonstrate for the first time the need for dual platelet receptor (PAR and FcγRIIA) stimulation for fibrin formation in HIT in vivo. These results extend our understanding of HIT pathophysiology and provide a scientific rationale for targeting the procoagulant phenotype as a possible therapeutic strategy in HIT.
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Affiliation(s)
- Stephanie A Renna
- The Cardeza Foundation for Hematologic Research, Center for Hemostasis, Thrombosis and Vascular Biology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.A.R., X.Z., P.M., J.V.M., S.E.M.)
| | - Xuefei Zhao
- The Cardeza Foundation for Hematologic Research, Center for Hemostasis, Thrombosis and Vascular Biology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.A.R., X.Z., P.M., J.V.M., S.E.M.)
| | - Satya P Kunapuli
- Sol Sherry Thrombosis Center and the Department of Physiology, Temple University School of Medicine, Philadelphia, PA (S.P.K.)
| | - Peisong Ma
- The Cardeza Foundation for Hematologic Research, Center for Hemostasis, Thrombosis and Vascular Biology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.A.R., X.Z., P.M., J.V.M., S.E.M.)
| | - Michael Holinstat
- Department of Pharmacology, University of Michigan, Ann Arbor (M.H.)
| | | | | | - James V Michael
- The Cardeza Foundation for Hematologic Research, Center for Hemostasis, Thrombosis and Vascular Biology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.A.R., X.Z., P.M., J.V.M., S.E.M.)
| | - Steven E McKenzie
- The Cardeza Foundation for Hematologic Research, Center for Hemostasis, Thrombosis and Vascular Biology, Department of Medicine, Thomas Jefferson University, Philadelphia, PA (S.A.R., X.Z., P.M., J.V.M., S.E.M.)
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Renna SA, McKenzie SE, Michael JV. Species Differences in Platelet Protease-Activated Receptors. Int J Mol Sci 2023; 24:ijms24098298. [PMID: 37176005 PMCID: PMC10179473 DOI: 10.3390/ijms24098298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 04/21/2023] [Accepted: 05/02/2023] [Indexed: 05/15/2023] Open
Abstract
Protease-activated receptors (PARs) are a class of integral membrane proteins that are cleaved by a variety of proteases, most notably thrombin, to reveal a tethered ligand and promote activation. PARs are critical mediators of platelet function in hemostasis and thrombosis, and therefore are attractive targets for anti-platelet therapies. Animal models studying platelet PAR physiology have relied heavily on genetically modified mouse strains, which have provided ample insight but have some inherent limitations. The current review aims to summarize the notable PAR expression and functional differences between the mouse and human, in addition to highlighting some recently developed tools to further study human physiology in mouse models.
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Affiliation(s)
- Stephanie A Renna
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Steven E McKenzie
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - James V Michael
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA 19107, USA
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5
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Huynh A, Arnold DM, Michael JV, Clare R, Smith JW, Daka M, Ianosi-Irimie M, McKenzie SE, Kelton JG, Nazy I. Characteristics of VITT antibodies in patients vaccinated with Ad26.COV2.S. Blood Adv 2023; 7:246-250. [PMID: 35377937 PMCID: PMC9860431 DOI: 10.1182/bloodadvances.2022007336] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/29/2022] [Accepted: 03/29/2022] [Indexed: 01/29/2023] Open
Affiliation(s)
- Angela Huynh
- Department of Medicine, Michael G. DeGroote School of Medicine
| | - Donald M. Arnold
- Department of Medicine, Michael G. DeGroote School of Medicine
- McMaster Centre for Transfusion Research, McMaster University, Hamilton, ON, Canada
| | - James V. Michael
- Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA
| | - Rumi Clare
- Department of Medicine, Michael G. DeGroote School of Medicine
| | - James W. Smith
- Department of Medicine, Michael G. DeGroote School of Medicine
| | - Mercy Daka
- Department of Medicine, Michael G. DeGroote School of Medicine
| | | | - Steven E. McKenzie
- Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, PA
| | - John G. Kelton
- Department of Medicine, Michael G. DeGroote School of Medicine
- McMaster Centre for Transfusion Research, McMaster University, Hamilton, ON, Canada
| | - Ishac Nazy
- Department of Medicine, Michael G. DeGroote School of Medicine
- McMaster Centre for Transfusion Research, McMaster University, Hamilton, ON, Canada
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Renna SA, Michael JV, Kong X, Ma L, Ma P, Nieman MT, Edelstein LC, McKenzie SE. Human and mouse PAR4 are functionally distinct receptors: Studies in novel humanized mice. J Thromb Haemost 2022; 20:1236-1247. [PMID: 35152546 DOI: 10.1111/jth.15669] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 01/28/2022] [Accepted: 02/07/2022] [Indexed: 08/31/2023]
Abstract
BACKGROUND Human and mouse platelets both express protease-activated receptor (PAR) 4 but sequence alignment reveals differences in several functional domains. These differences may result in functional disparities between the receptors which make it difficult to translate PAR4 studies using mice to human platelet physiology. OBJECTIVES To generate transgenic mice that express human, but not mouse, PAR4 and directly compare human and mouse PAR4 function in the same platelet environment. METHODS Transgenic mice were made using a genomic clone of the F2RL3 gene (encoding PAR4) and backcrossed with Par4 KO mice. For certain experiments, mice were bred with GRK6 KO mice. Tail bleeding time and platelet function in response to PAR4-activating peptide were assessed. RESULTS Human F2RL3 was successfully integrated into the mouse genome, transgenic mice were crossed to the mPar4 KO background (PAR4 tg/KO), and PAR4 was functionally expressed on platelets. Compared to WT, PAR4 tg/KO mice exhibited shortened tail bleeding time and their platelets were more responsive to PAR4-AP as assessed by α-granule release and integrin activation. The opposite was observed with thrombin. Knocking out GRK6 had no effect on human PAR4-expressing platelets, unlike mouse Par4-expressing platelets. PAR4 tg/KO platelets exhibited greater Ca2+ area under the curve and more robust extracellular vesicle release than WT stimulated with PAR4-AP. CONCLUSION These data suggest that (1) human PAR4- and mouse Par4-mediated signaling are different and (2) the feedback regulation mechanisms of human and mouse PAR4 are different. These functional differences are important to consider when interpreting PAR4 studies done with mice.
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Affiliation(s)
- Stephanie A Renna
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - James V Michael
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Xianguo Kong
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Lin Ma
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Peisong Ma
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Marvin T Nieman
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Leonard C Edelstein
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Steven E McKenzie
- Department of Medicine, The Cardeza Foundation for Hematologic Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
- Department of Pharmacology, Case Western Reserve University, Cleveland, Ohio, USA
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7
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Patel P, Michael JV, Naik UP, McKenzie SE. Platelet FcγRIIA in immunity and thrombosis: Adaptive immunothrombosis. J Thromb Haemost 2021; 19:1149-1160. [PMID: 33587783 DOI: 10.1111/jth.15265] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/14/2021] [Accepted: 02/09/2021] [Indexed: 12/16/2022]
Abstract
Sepsis and autoimmune diseases remain major causes of morbidity and mortality. The last decade has seen a new appreciation of platelets in host defense, in both immunity and thrombosis. Platelets are first responders in the blood to microbes or non-microbial antigens. The role of platelets in physiologic immunity is counterbalanced by their role in pathology, for example, microvascular thrombosis. Platelets encounter microbes and antigens via both innate and adaptive immune processes; platelets also help to shape the subsequent adaptive response. FcγRIIA is a receptor for immune complexes opsonized by IgG or pentraxins, and expressed in humans by platelets, granulocytes, monocytes and macrophages. With consideration of the roles of IgG and Fc receptors, the host response to microbes and autoantigens can be called adaptive immunothrombosis. Here we review newer developments involving platelet FcγRIIA in humans and humanized mice in immunity and thrombosis, with special attention to heparin-induced thrombocytopenia, systemic lupus erythematosus, and bacterial sepsis. Human genetic diversity in platelet receptors and the utility of humanized mouse models are highlighted.
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Affiliation(s)
- Pravin Patel
- Department of Medicine, Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - James V Michael
- Department of Medicine, Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Ulhas P Naik
- Department of Medicine, Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Steven E McKenzie
- Department of Medicine, Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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Abstract
Clinical management of asthma and chronic obstructive pulmonary disease (COPD) has primarily relied on the use of beta 2 adrenergic receptor agonists (bronchodilators) and corticosteroids, and more recently, monoclonal antibody therapies (biologics) targeting specific cytokines and their functions. Although these approaches provide relief from exacerbations, questions remain on their long-term efficacy and safety. Furthermore, current therapeutics do not address progressive airway remodeling (AR), a key pathological feature of severe obstructive lung disease. Strikingly, agonists of the bitter taste receptors (TAS2Rs) deliver robust bronchodilation, curtail allergen-induced inflammatory responses in the airways and regulate airway smooth muscle (ASM) cell proliferation and mitigate features of AR in vitro and in animal models. The scope of this review is to provide a comprehensive and systematic insight into our current understanding of TAS2Rs with an emphasis on the molecular events that ensue TAS2R activation in distinct airway cell types and expand on the pleiotropic effects of TAS2R targeting in mitigating various pathological features of obstructive lung diseases. Finally, we will discuss specific opportunities that could help the development of selective agonists for specific TAS2R subtypes in the treatment of asthma.
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Affiliation(s)
- Ajay P Nayak
- Division of Pulmonary, Allergy and Critical Care Medicine, Center for Translational Medicine, Department of Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, United States
| | - Sushrut D Shah
- Division of Pulmonary, Allergy and Critical Care Medicine, Center for Translational Medicine, Department of Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, United States
| | - James V Michael
- Division of Pulmonary, Allergy and Critical Care Medicine, Center for Translational Medicine, Department of Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, United States
| | - Deepak A Deshpande
- Division of Pulmonary, Allergy and Critical Care Medicine, Center for Translational Medicine, Department of Medicine, Jane and Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, PA, United States
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9
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Nayak AP, Pera T, Deshpande DA, Michael JV, Liberato JR, Pan S, Tompkins E, Morelli HP, Yi R, Wang N, Penn RB. Regulation of ovarian cancer G protein-coupled receptor-1 expression and signaling. Am J Physiol Lung Cell Mol Physiol 2019; 316:L894-L902. [PMID: 30724097 DOI: 10.1152/ajplung.00426.2018] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Ovarian cancer G protein-coupled receptor 1 (OGR1) is a recently deorphanized G protein-coupled receptor shown to signal in response to low extracellular pH (↓pHo) or certain benzodiazepines. The pleiotropic nature of OGR1 signaling in human airway smooth muscle (HASM) cells suggests that OGR1 is a potential therapeutic target for the management of obstructive lung diseases. However, the basic pharmacological and regulatory features of OGR1 remain poorly understood. We employed model systems of heterologously expressed [human embryonic kidney 293 (HEK293) cells] or endogenous (HASM) OGR1 to assess changes in expression, subcellular localization, and signaling capabilities following acute or chronic treatment with ↓pHo or the benzodiazepines lorazepam and sulazepam. In HEK293 cells expressing OGR1, treatment with ↓pHo and/or lorazepam, but not sulazepam, caused rapid OGR1 internalization. In HASM cells, acute treatment with ↓pHo or benzodiazepines did not alter abundance of OGR1 mRNA; however, significant downregulation was observed following chronic treatment. Acute and chronic pretreatment of HASM cells with sulazepam or lorazepam resulted in receptor desensitization as demonstrated by reduced phosphorylation of vasodilator-stimulated phosphoprotein (VASP) or p42/p44 upon rechallenge. Acid (acute but not chronic) pretreatment of HASM cells induced desensitization of OGR1-mediated VASP (but not p42/p44) phosphorylation. In contrast to a recent study reporting OGR1 upregulation and sensitization in cardiac tissue subject to ischemic/acidic insult, chronic OGR1 activation in multiple model systems did not increase OGR1 expression or signaling capacity. The ability to induce OGR1 internalization and desensitization was activator dependent, reflecting the ability of different activators to induce specific receptor confirmations and engagement of specific heterotrimeric G proteins.
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Affiliation(s)
- Ajay P Nayak
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Tonio Pera
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Deepak A Deshpande
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - James V Michael
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Jennifer R Liberato
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Shi Pan
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Eric Tompkins
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Henry P Morelli
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Roslyn Yi
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Nadan Wang
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Raymond B Penn
- Department of Medicine, Center for Translational Medicine and Division of Pulmonary, Allergy and Critical Care Medicine; and Jane & Leonard Korman Respiratory Institute, Thomas Jefferson University, Philadelphia, Pennsylvania
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10
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Michael JV, Gavrila A, Nayak AP, Pera T, Liberato JR, Polischak SR, Shah SD, Deshpande DA, Penn RB. Cooperativity of E-prostanoid receptor subtypes in regulating signaling and growth inhibition in human airway smooth muscle. FASEB J 2019; 33:4780-4789. [PMID: 30601680 DOI: 10.1096/fj.201801959r] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Prostaglandin E2 (PGE2) is produced in the airway during allergic lung inflammation and both promotes and inhibits features of asthma pathology. These mixed effects relate to 4 E-prostanoid (EP) receptor subtypes (EP1, 2, 3 and 4) expressed at different levels on different resident and infiltrating airway cells. Although studies have asserted both EP2 and EP4 expression in human airway smooth muscle (HASM), a recent study asserted EP4 to be the functionally dominant EP subtype in HASM. Herein, we employ recently-developed subtype-selective ligands to investigate singular or combined EP2 and EP4 receptor activation in regulating HASM signaling and proliferation. The subtype specificity of ONO-AE1-259-01 (EP2 agonist) and ONO-AE1-329 (EP4 agonist) was first demonstrated in human embryonic kidney 293 cells stably expressing different EP receptor subtypes. EP receptor knockdown and subtype-selective antagonists demonstrated EP2 and EP4 receptor responsiveness in HASM cells to the specific ONO compounds, whereas PGE2 appeared to preferentially signal via the EP4 receptor. Both singular EP2 and EP4 receptor agonists inhibited HASM proliferation, and combined EP2 and EP4 receptor agonism exhibited positive cooperativity in both chronic Gs-mediated signaling and inhibiting HASM proliferation. These findings suggest both EP2 and EP4 are functionally important in HASM, and their combined targeting optimally inhibits airway smooth muscle proliferation.-Michael, J. V. Gavrila, A., Nayak, A. P., Pera, T., Liberato, J. R., Polischak, S. R., Shah, S. D., Deshpande, D. A., Penn, R. B. Cooperativity of E-prostanoid receptor subtypes in regulating signaling and growth inhibition in human airway smooth muscle.
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Affiliation(s)
- James V Michael
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Adelina Gavrila
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Ajay P Nayak
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Tonio Pera
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Jennifer R Liberato
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Steven R Polischak
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Sushrut D Shah
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Deepak A Deshpande
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Raymond B Penn
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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11
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Pera T, Deshpande DA, Ippolito M, Wang B, Gavrila A, Michael JV, Nayak AP, Tompkins E, Farrell E, Kroeze WK, Roth BL, Panettieri RA, Benovic JL, An SS, Dulin NO, Penn RB. Biased signaling of the proton-sensing receptor OGR1 by benzodiazepines. FASEB J 2018; 32:862-874. [PMID: 29042451 PMCID: PMC5888400 DOI: 10.1096/fj.201700555r] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Accepted: 10/02/2017] [Indexed: 01/01/2023]
Abstract
GPCRs have diverse signaling capabilities, based on their ability to assume various conformations. Moreover, it is now appreciated that certain ligands can promote distinct receptor conformations and thereby bias signaling toward a specific pathway to differentially affect cell function. The recently deorphanized G protein-coupled receptor OGR1 [ovarian cancer G protein-coupled receptor 1 ( GPR68)] exhibits diverse signaling events when stimulated by reductions in extracellular pH. We recently demonstrated airway smooth muscle cells transduce multiple signaling events, reflecting a diverse capacity to couple to multiple G proteins. Moreover, we recently discovered that the benzodiazepine lorazepam, more commonly recognized as an agonist of the γ-aminobutyric acid A (GABAA) receptor, can function as an allosteric modulator of OGR1 and, similarly, can promote multiple signaling events. In this study, we demonstrated that different benzodiazepines exhibit a range of biases for OGR1, with sulazepam selectively activating the canonical Gs of the G protein signaling pathway, in heterologous expression systems, as well as in several primary cell types. These findings highlight the potential power of biased ligand pharmacology for manipulating receptor signaling qualitatively, to preferentially activate pathways that are therapeutically beneficial.-Pera, T., Deshpande, D. A., Ippolito, M., Wang, B., Gavrila, A., Michael, J. V., Nayak, A. P., Tompkins, E., Farrell, E., Kroeze, W. K., Roth, B. L., Panettieri, R. A. Jr Benovic, J. L., An, S. S., Dulin, N. O., Penn, R. B. Biased signaling of the proton-sensing receptor OGR1 by benzodiazepines.
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Affiliation(s)
- Tonio Pera
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Deepak A. Deshpande
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Michael Ippolito
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Bin Wang
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Adelina Gavrila
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - James V. Michael
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Ajay P. Nayak
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Eric Tompkins
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Eleni Farrell
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Wesley K. Kroeze
- Department of Pharmacology, University of North Carolina, Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
- National Institute of Mental Health Psychoactive Drug Screening Program, School of Medicine, University of North Carolina, Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
| | - Bryan L. Roth
- Department of Pharmacology, University of North Carolina, Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
- National Institute of Mental Health Psychoactive Drug Screening Program, School of Medicine, University of North Carolina, Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA
- Division of Chemical Biology and Medicinal Chemistry, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Reynold A. Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey, USA
| | - Jeffrey L. Benovic
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Steven S. An
- Department of Environmental Health and Engineering, Johns Hopkins University, Bloomberg School of Public Health, Baltimore, Maryland, USA; and
| | - Nickolai O. Dulin
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, University of Chicago, Chicago, Illinois, USA
| | - Raymond B. Penn
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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12
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Yoo EJ, Cao G, Koziol‐White CJ, Ojiaku CA, Sunder K, Jude JA, Michael JV, Lam H, Pushkarsky I, Damoiseaux R, Di Carlo D, Ahn K, An SS, Penn RB, Panettieri RA. Gα 12 facilitates shortening in human airway smooth muscle by modulating phosphoinositide 3-kinase-mediated activation in a RhoA-dependent manner. Br J Pharmacol 2017; 174:4383-4395. [PMID: 28921504 PMCID: PMC5715591 DOI: 10.1111/bph.14040] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 09/12/2017] [Accepted: 09/12/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE PI3K-dependent activation of Rho kinase (ROCK) is necessary for agonist-induced human airway smooth muscle cell (HASMC) contraction, and inhibition of PI3K promotes bronchodilation of human small airways. The mechanisms driving agonist-mediated PI3K/ROCK axis activation, however, remain unclear. Given that G12 family proteins activate ROCK pathways in other cell types, their role in M3 muscarinic acetylcholine receptor-stimulated PI3K/ROCK activation and contraction was examined. EXPERIMENTAL APPROACH Gα12 coupling was evaluated using co-immunoprecipitation and serum response element (SRE)-luciferase reporter assays. siRNA and pharmacological approaches, as well as overexpression of a regulator of G-protein signaling (RGS) proteins were applied in HASMCs. Phosphorylation levels of Akt, myosin phosphatase targeting subunit-1 (MYPT1), and myosin light chain-20 (MLC) were measured. Contraction and shortening were evaluated using magnetic twisting cytometry (MTC) and micro-pattern deformation, respectively. Human precision-cut lung slices (hPCLS) were utilized to evaluate bronchoconstriction. KEY RESULTS Knockdown of M3 receptors or Gα12 attenuated activation of Akt, MYPT1, and MLC phosphorylation. Gα12 coimmunoprecipitated with M3 receptors, and p115RhoGEF-RGS overexpression inhibited carbachol-mediated induction of SRE-luciferase reporter. p115RhoGEF-RGS overexpression inhibited carbachol-induced activation of Akt, HASMC contraction, and shortening. Moreover, inhibition of RhoA blunted activation of PI3K. Lastly, RhoA inhibitors induced dilation of hPCLS. CONCLUSIONS AND IMPLICATIONS Gα12 plays a crucial role in HASMC contraction via RhoA-dependent activation of the PI3K/ROCK axis. Inhibition of RhoA activation induces bronchodilation in hPCLS, and targeting Gα12 signaling may elucidate novel therapeutic targets in asthma. These findings provide alternative approaches to the clinical management of airway obstruction in asthma.
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Affiliation(s)
- Edwin J Yoo
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - Gaoyuan Cao
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - Cynthia J Koziol‐White
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - Christie A Ojiaku
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - Krishna Sunder
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - Joseph A Jude
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
| | - James V Michael
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung CenterThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Hong Lam
- Department of Environmental Health and EngineeringJohns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA
| | - Ivan Pushkarsky
- Department of BioengineeringUniversity of CaliforniaLos AngelesCAUSA
| | - Robert Damoiseaux
- Department of Molecular and Medicinal PharmacologyUniversity of CaliforniaLos AngelesCAUSA
- California NanoSystems InstituteUniversity of CaliforniaLos AngelesCAUSA
| | - Dino Di Carlo
- Department of BioengineeringUniversity of CaliforniaLos AngelesCAUSA
- California NanoSystems InstituteUniversity of CaliforniaLos AngelesCAUSA
- Department of Mechanical EngineeringUniversity of CaliforniaLos AngelesCAUSA
| | - Kwangmi Ahn
- National Institute of Mental HealthBethesdaMDUSA
| | - Steven S An
- Department of Environmental Health and EngineeringJohns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMDUSA
| | - Raymond B Penn
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung CenterThomas Jefferson UniversityPhiladelphiaPAUSA
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health InstituteRutgers UniversityNew BrunswickNJUSA
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13
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Abstract
Together H-, N- and KRAS mutations are major contributors to ~30% of all human cancers. Thus, Ras inhibition remains an important anti-cancer strategy. The molecular mechanisms of isotypic Ras oncogenesis are still not completely understood. Monopharmacological therapeutics have not been successful in the clinic. These disappointing outcomes have led to attempts to target elements downstream of Ras, mainly targeting either the Phosphatidylinositol 3-Kinase (PI3K) or Mitogen-Activated Protein Kinase (MAPK) pathways. While several such approaches are moderately effective, recent efforts have focused on preclinical evaluation of combination therapies to improve efficacies. This review will detail current understanding of the contributions of plasma membrane microdomain targeting of Ras to mitogenic and tumorigenic signaling and tumor progression. Moreover, this review will outline novel approaches to target Ras in cancers, including targeting schemes for new drug development, as well as putative re-purposing of drugs in current use to take advantage of blunting Ras signaling by interfering with Ras plasma membrane microdomain targeting and retention.
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Affiliation(s)
- Lawrence E Goldfinger
- Department of Anatomy & Cell Biology and The Sol Sherry Thrombosis Research Center, Lewis Katz School of Medicine at Temple University, and Cancer Biology Program, Fox Chase Cancer Center
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14
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Michael JV, Wurtzel JGT, Goldfinger LE. Inhibition of Galectin-1 Sensitizes HRAS-driven Tumor Growth to Rapamycin Treatment. Anticancer Res 2017; 36:5053-5061. [PMID: 27798864 DOI: 10.21873/anticanres.11074] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/15/2016] [Indexed: 11/10/2022]
Abstract
The goal of this study was to develop combinatorial application of two drugs currently either in active use as anticancer agents (rapamycin) or in clinical trials (OTX008) as a novel strategy to inhibit Harvey RAS (HRAS)-driven tumor progression. HRAS anchored to the plasma membrane shuttles from the lipid ordered (Lo) domain to the lipid ordered/lipid disordered border upon activation, and retention of HRAS at these sites requires galectin-1. We recently showed that genetically enforced Lo sequestration of HRAS inhibited mitogen-activated protein kinase (MAPK) signaling, but not phoshatidylinositol 3-kinase (PI3K) activation. Here we show that inhibition of galectin-1 with OTX008 sequestered HRAS in the Lo domain, blocked HRAS-mediated MAPK signaling, and attenuated HRAS-driven tumor progression in mice. HRAS-driven tumor growth was also attenuated by treatment with mammalian target of rapamycin (mTOR) inhibitor rapamycin, and this effect was further enhanced in tumors driven by Lo-sequestered HRAS. These drugs also revealed bidirectional cross-talk in HRAS pathways. Moreover, dual pathway inhibition with OTX008 and rapamycin resulted in nearly complete ablation of HRAS-driven tumor growth. These findings indicate that membrane microdomain sequestration of HRAS with galectin-1 inhibition, coupled with mTOR inhibition, may support a novel therapeutic approach to treat HRAS-mutant cancer.
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Affiliation(s)
- James V Michael
- Department of Anatomy and Cell Biology, The Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
| | - Jeremy G T Wurtzel
- Department of Anatomy and Cell Biology, The Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A
| | - Lawrence E Goldfinger
- Department of Anatomy and Cell Biology, The Sol Sherry Thrombosis Research Center, Temple University School of Medicine, Philadelphia, PA, U.S.A. .,Cancer Biology Program, Fox Chase Cancer Center, Philadelphia, PA, U.S.A
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15
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Michael JV, Wurtzel JGT, Goldfinger LE. Abstract 1870: Inhibition of Galectin-1 sensitizes oncogenic H-Ras to Rapamycin treatment. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-1870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Specific plasma membrane (PM) localization is essential for H-Ras signaling, and relies on post-translational modifications on the C-terminal targeting domain. H-Ras shuttles from the lipid ordered (Lo) domain to the lipid ordered/lipid disordered (Lo/Ld) border upon activation, which is dependent on Galectin-1. We have previously found that H-Ras, which is sequestered in the Lo domain by swapping the C-terminal targeting domain with the Lo-sequestering targeting domain of R-Ras, is deficient in MAPK signal propagation, while having no effect on PI3K activation, nor on H-Ras-driven tumor progression. We have further found that inhibition of PI3K with LY294002 inhibited tumor progression by H-Ras with or without Lo sequestration. Here we show that Lo sequestration of H-Ras attenuated, but did not completely block, H-Ras-induced mTOR signaling (S6kinase phosphorylation) despite similar activation of PI3K as H-Ras. Interestingly, MEK inhibition with U0126 diminished S6kinase phosphorylation by H-Ras, as well as by Lo-sequestered H-Ras. Here we demonstrate that H-Ras-driven allograft tumor growth in mice was substantially blunted upon treatment with mTOR inhibitor Rapamycin, and this effect of Rapamycin was further enhanced in tumors driven by Lo-sequestered H-Ras. Moreover, Rapamycin treatment ablated ERK phosphorylation in H-Ras tumors as well as in tumors with Lo-sequestered H-Ras (in which ERK phosphorylation was already greatly reduced). Together these findings indicate that Lo sequestration of H-Ras inhibits MAPK pathway activation, and that the MAPK pathway engages in crosstalk with mTOR pathways by regulating S6kinase phosphorylation downstream of H-Ras, whereas mTOR activity is required for H-Ras-induced MAPK signaling. These data further indicate that mTOR activation downstream of H-Ras is sufficient to drive tumorigenesis, but this pathway also requires H-Ras-MAPK activation. To recapitulate H-Ras Lo sequestration by the C-terminal targeting domain swap genetic model, we used a Galectin-1 inhibitor, OTX008, to disrupt H-Ras from transitioning between the Lo and Ld domains. OTX008 treatment alone inhibited H-Ras-driven allograft tumor growth to a similar extent as Rapamycin. However, a combination of OTX008 and Rapamycin resulted in nearly complete ablation of H-Ras-dependent tumor growth. These findings indicate that blockade of H-Ras targeting to the lipid ordered/disordered plasma membrane microdomain border, coupled with blockade of mTOR signaling, could provide a novel therapeutic approach to treat H-Ras-associated cancers.
Citation Format: James V. Michael, Jeremy G T Wurtzel, Lawrence E. Goldfinger. Inhibition of Galectin-1 sensitizes oncogenic H-Ras to Rapamycin treatment. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1870.
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16
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Michael JV, Wurtzel JG, Mao GF, Rao AK, Hoffman NE, Rajan S, Madesh M, Jana F, Nieman M, Rowley JW, Weyrich AS, Goldfinger LE. Abstract 2667: Platelet microparticles infiltrating solid tumors transfer miRNAs and modulate tumor angiogenesis and growth. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-2667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Platelet-derived microparticles are associated with enhancement of metastasis and poor cancer outcomes. Platelet microparticles can transfer platelet microRNAs (miRNAs) to vascular cells upon co-incubation in vitro, but the contributions of platelet microparticles and miRNAs to tumor progression are still poorly understood. Tumor vasculature is highly permeable, allowing the possibility of platelet microparticle-tumor cell interaction in primary solid tumors. Here we show that platelet microparticles infiltrate solid tumors in humans and mice, attach to tumor cells, and transfer platelet-derived RNA, including miRNAs, to tumor cells in vivo as well as in vitro. MiR-24 was a major species in this transfer. We identified RNA targets of platelet-derived miR-24 in lung carcinoma cells, which included mt-Nd2, a mitochondrial mRNA which lacks a 3’-UTR, and Snora75, a non-coding small nucleolar RNA. These RNAs were depleted in platelet microparticle-treated tumor cells, resulting in mitochondrial dysfunction and tumor cell growth inhibition, in a miR-24-dependent manner. Blockade of miR-24 in tumor cells accelerated tumor growth in vivo, and prevented tumor growth inhibition by platelet microparticle transfusion. Thus, platelet microparticles inhibit lung carcinoma cell proliferation and solid tumor growth via transfer of miR-24. However, global depletion of platelet miRNAs by platelet-specific deletion of Dicer1 inhibited tumor angiogenesis, platelet microparticle infiltration, and delayed tumor growth in mice. Thus, platelet-derived miRNAs transfer in vivo to tumor cells in solid tumors via microparticles, regulate tumor cell gene expression, and modulate tumor progression, whereas platelet miRNAs promote tumor angiogenesis. These findings shed novel insight onto mechanisms of horizontal gene transfer and add multiple layers to the regulatory roles of miRNAs and platelet microparticles in tumor progression.
Citation Format: James V. Michael, Jeremy G.T. Wurtzel, Guang Fen Mao, A. Koneti Rao, Nicholas E. Hoffman, Sudarsan Rajan, Muniswamy Madesh, Fabian Jana, Marvin Nieman, Jesse W. Rowley, Andrew S. Weyrich, Lawrence E. Goldfinger. Platelet microparticles infiltrating solid tumors transfer miRNAs and modulate tumor angiogenesis and growth. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2667.
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Affiliation(s)
| | | | - Guang Fen Mao
- 1Temple University School of Medicine, Philadelphia, PA
| | - A. Koneti Rao
- 1Temple University School of Medicine, Philadelphia, PA
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17
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Silver L, Michael JV, Goldfinger LE, Gallo G. Activation of PI3K and R-Ras signaling promotes the extension of sensory axons on inhibitory chondroitin sulfate proteoglycans. Dev Neurobiol 2014; 74:918-33. [PMID: 24578264 DOI: 10.1002/dneu.22174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 02/24/2014] [Indexed: 12/22/2022]
Abstract
Chondroitin sulfate proteoglycans (CSPGs) are extracellular inhibitors of axon extension and plasticity, and cause growth cones to exhibit dystrophic behaviors. Phosphoinositide 3-kinase (PI3K) is a lipid kinase activated by axon growth promoting signals. In this study, we used embryonic chicken dorsal root ganglion neurons to determine if CSPGs impair signaling through PI3K. We report that CSPGs inhibit PI3K signaling in axons and growth cones, as evidenced by decreased levels of phosphorylated downstream kinases (Akt and S6). Direct activation of PI3K signaling, using a cell permeable phosphopeptide (PI3Kpep), countered the effects of CSPGs on growth cones and axon extension. Both overnight and acute treatment with PI3Kpep promoted axon extension on CSPG-coated substrates. The R-Ras GTPase is an upstream positive regulator of PI3K signaling. Expression of constitutively active R-Ras promoted axon extension and growth cone elaboration on CSPGs and permissive substrata. In contrast, an N-terminus-deleted constitutively active R-Ras, deficient in PI3K activation, promoted axon extension but not growth cone elaboration on CSPGs and permissive substrata. These data indicate that activation of R-Ras-PI3K signaling may be a viable approach for manipulating axon extension on CSPGs.
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Affiliation(s)
- Lee Silver
- Department of Anatomy and Cell Biology, Temple University School of Medicine, 3500 North Broad St., Philadelphia, Pennsylvania, 19140; Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Philadelphia, Pennsylvania, 19140
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18
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Peukert SL, Labbe NJ, Sivaramakrishnan R, Michael JV. Direct measurements of rate constants for the reactions of CH3 radicals with C2H6, C2H4, and C2H2 at high temperatures. J Phys Chem A 2013; 117:10228-38. [PMID: 23968575 DOI: 10.1021/jp4073153] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The shock tube technique has been used to study the reactions CH3 + C2H6 → C2H4 + CH4 + H (1), CH3 + C2H4 → Products + H (2), and CH3 + C2H2 → Products + H (3). Biacetyl, (CH3CO)2, was used as a clean high temperature thermal source for CH3-radicals for all the three reactions studied in this work. For reaction 1, the experiments span a T-range of 1153 K ≤ T ≤ 1297 K, at P ~ 0.4 bar. The experiments on reaction 2 cover a T-range of 1176 K ≤ T ≤ 1366 K, at P ~ 1.0 bar, and those on reaction 3 a T-range of 1127 K ≤ T ≤ 1346 K, at P ~ 1.0 bar. Reflected shock tube experiments performed on reactions 1-3, monitored the formation of H-atoms with H-atom Atomic Resonance Absorption Spectrometric (ARAS). Fits to the H-atom temporal profiles using an assembled kinetics model were used to make determinations for k1, k2, and k3. In the case of C2H6, the measurements of [H]-atoms were used to derive direct high-temperature rate constants, k1, that can be represented by the Arrhenius equation k1(T) = 5.41 × 10(-12) exp(-6043 K/T) cm(3) molecules(-1) s(-1) (1153 K ≤ T ≤ 1297 K) for the only bimolecular process that occurs, H-atom abstraction. TST calculations based on ab initio properties calculated at the CCSD(T)/CBS//M06-2X/cc-pVTZ level of theory show excellent agreement, within ±20%, of the measured rate constants. For the reaction of CH3 with C2H4, the present rate constant results, k2', refer to the sum of rate constants, k(2b) + k(2c), from two competing processes, addition-elimination, and the direct abstraction CH3 + C2H4 → C3H6 + H (2b) and CH3 + C2H4 → C2H2 + H + CH4 (2c). Experimental rate constants for k2' can be represented by the Arrhenius equation k2'(T) = 2.18 × 10(-10) exp(-11830 K/T) cm(3) molecules(-1) s(-1) (1176 K ≤ T ≤ 1366 K). The present results are in excellent agreement with recent theoretical predictions. The present study provides the only direct measurement for the high-temperature rate constants for these channels. Lastly, measurements of H-atoms from the reaction of CH3 with C2H2 provided direct unambiguous determinations of the rate constant for the dominant process under the present experimental conditions, the addition-elimination, CH3 + C2H2 → p-C3H4 + H (3b). Experimental rate constants for k(3b) can be represented by the Arrhenius equation k(3b)(T) = 5.16 × 10(-13) exp(-3852 K/T) cm(3) molecules(-1) s(-1) (1127 K ≤ T ≤ 1346 K). The present determinations for k(3b) represent the only direct measurements for this reaction and are also in good agreement with recent theoretical predictions. The present experimental k(3b) values were also used to derive rate constants, k(-3b), for the more extensively studied back-process, the reaction of H-atoms with propyne. The best fit Arrhenius equation, combining the presently derived k(-3b) values with a recent experimental determination for k(-3b), can be represented by k(-3b)(T) = 3.87 × 10(-11) exp(-1313 K/T) cm(3) molecules(-1) s(-1) (870 K ≤ T ≤ 1346 K). The present studies represent a novel implementation of the sensitive H-ARAS technique to measure rate constants for poorly characterized and difficult to isolate "slow" CH3-radical reactions with stable C2 hydrocarbons.
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Affiliation(s)
- S L Peukert
- Chemical Sciences and Engineering Division, Argonne National Laboratory , Argonne, Illinois 60439, United States
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19
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Sivaramakrishnan R, Michael JV, Harding LB, Klippenstein SJ. Shock tube explorations of roaming radical mechanisms: the decompositions of isobutane and neopentane. J Phys Chem A 2012; 116:5981-9. [PMID: 22394380 DOI: 10.1021/jp210959j] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The thermal decompositions of isobutane and neopentane have been studied using both shock tube experiments and ab initio transition state theory based master equation calculations. Dissociation rate constants for these molecules have been measured at high temperatures (1260-1566 K) behind reflected shock waves using high-sensitivity H-ARAS detection. The two major dissociation channels at high temperature are iso-C(4)H(10) → CH(3) + i-C(3)H(7) (1a) and neo-C(5)H(12) → CH(3) + t-C(4)H(9) (2a). Ultrahigh-sensitivity ARAS detection of H-atoms produced from the rapid decomposition of the product radicals, i-C(3)H(7) in (1a) and t-C(4)H(9) in (2a), through i-C(3)H(7) + M → H + C(3)H(6) + M (3a) and t-C(4)H(9) + M → H + i-C(4)H(8) + M (4a) allowed measurements of both the total decomposition rate constants, k(total), and the branching to radical products, which were observed to be equivalent in both systems, k(1a)/k(total) and k(2a)/k(total) = 0.79 ± 0.05. Theoretical analyses indicate that in isobutane, the non-H-atom fraction has two contributions, the dominant fraction being due to the roaming radical mechanism leading to molecular products through iso-C(4)H(10) → CH(4) + C(3)H(6) (1b) with k(1b)/k(total) = 0.16, and a minor fraction that involves the isomerization of i-C(3)H(7) to n-C(3)H(7) that then subsequently forms methyl radicals, i-C(3)H(7) + M → n-C(3)H(7) + M → CH(3) + C(2)H(4) + M (3b). In contrast to isobutane, in neopentane, the contribution to the non-H-atom fraction is exclusively through the roaming radical mechanism that leads to neo-C(5)H(12) → CH(4) + i-C(4)H(8) (2b) with k(2b)/k(total) = 0.21. These quantitative measurements of larger contributions from the roaming mechanism for larger molecules are in agreement with the qualitative theoretical arguments that suggest long-range dispersion interactions (which become increasingly important for larger molecules) may enhance roaming.
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Affiliation(s)
- R Sivaramakrishnan
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
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Srinivasan NK, Su MC, Michael JV, Klippenstein SJ, Harding LB. Reflected Shock Tube and Theoretical Studies of High-Temperature Rate Constants for OH + CF3H ⇆ CF3 + H2O and CF3 + OH → Products. J Phys Chem A 2007; 111:6822-31. [PMID: 17503789 DOI: 10.1021/jp0706228] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reflected shock tube technique with multipass absorption spectrometric detection of OH radicals at 308 nm, using either 36 or 60 optical passes corresponding to total path lengths of 3.25 or 5.25 m, respectively, has been used to study the bimolecular reactions, OH+CF3H-->CF3+H2O (1) and CF3+H2O-->OH+CF3H (-1), between 995 and 1663 K. During the course of the study, estimates of rate constants for CF3+OH-->products (2) could also be determined. Experiments on reaction -1 were transformed through equilibrium constants to k1, giving the Arrhenius expression k1=(9.7+/-2.1)x10(-12) exp(-4398+/-275K/T) cm3 molecule(-1) s(-1). Over the temperature range, 1318-1663 K, the results for reaction 2 were constant at k2=(1.5+/-0.4)x10(-11) cm3 molecule(-1) s(-1). Reactions 1 and -1 were also studied with variational transition state theory (VTST) employing QCISD(T) properties for the transition state. These a priori VTST predictions were in good agreement with the present experimental results but were too low at the lower temperatures of earlier experiments, suggesting that either the barrier height was overestimated by about 1.3 kcal/mol or that the effect of tunneling was greatly underestimated. The present experimental results have been combined with the most accurate earlier studies to derive an evaluation over the extended temperature range of 252-1663 K. The three parameter expression k1=2.08x10(-17) T1.5513 exp(-1848 K/T) cm3 molecule(-1) s(-1) describes the rate behavior over this temperature range. Alternatively, the expression k1,th=1.78x10(-23) T3.406 exp(-837 K/T) cm3 molecule(-1) s(-1) obtained from empirically adjusted VTST calculations over the 250-2250 K range agrees with the experimental evaluation to within a factor of 1.6. Reaction 2 was also studied with direct CASPT2 variable reaction coordinate transition state theory. The resulting predictions for the capture rate are found to be in good agreement with the mean of the experimental results and can be represented by the expression k2,th=2.42x10(-11) T-0.0650 exp(134 K/T) cm3 molecule(-1) s(-1) over the 200-2500 K temperature range. The products of this reaction are predicted to be CF2O+HF.
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Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Srinivasan NK, Su MC, Michael JV. High-temperature rate constants for CH3OH + Kr --> products, OH + CH3OH --> products, OH + (CH3)(2)CO --> CH2COCH3 + H2O, and OH + CH3 --> CH) + H2O. J Phys Chem A 2007; 111:3951-8. [PMID: 17388365 DOI: 10.1021/jp0673516] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reflected shock tube technique with multipass absorption spectrometric detection of OH radicals at 308 nm (corresponding to a total path length of approximately 4.9 m) has been used to study the dissociation of methanol between 1591 and 2865 K. Rate constants for two product channels [CH3OH + Kr --> CH3 + OH + Kr (1) and CH3OH + Kr --> 1CH2 + H2O + Kr (2)] were determined. During the course of the study, it was necessary to determine several other rate constants that contributed to the profile fits. These include OH + CH3OH --> products, OH + (CH3)2CO --> CH2COCH3 + H2O, and OH + CH3 --> 1,3CH2 + H2O. The derived expressions, in units of cm(3) molecule(-1) s(-1), are k(1) = 9.33 x 10(-9) exp(-30857 K/T) for 1591-2287 K, k(2) = 3.27 x 10(-10) exp(-25946 K/T) for 1734-2287 K, kOH+CH3OH = 2.96 x 10-16T1.4434 exp(-57 K/T) for 210-1710 K, k(OH+(CH3)(2)CO) = (7.3 +/- 0.7) x 10(-12) for 1178-1299 K and k(OH+CH3) = (1.3 +/- 0.2) x 10(-11) for 1000-1200 K. With these values along with other well-established rate constants, a mechanism was used to obtain profile fits that agreed with experiment to within <+/-10%. The values obtained for reactions 1 and 2 are compared with earlier determinations and also with new theoretical calculations that are presented in the preceding article in this issue. These new calculations are in good agreement with the present data for both (1) and (2) and also for OH + CH3 --> products.
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Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Abstract
The reflected shock tube technique with multi-pass absorption spectrometric detection of OH-radicals at 308 nm (corresponding to a total path length of approximately 4.9 m) has been used to study the reactions, OH + C(2)H(2)--> products (1) and OH + C(2)H(4)--> C(2)H(3) + H(2)O (2). The present optical configuration gives a S/N ratio of approximately 1 at approximately 0.5-1.0 x 10(12) radicals cm(-3). Hence, kinetics experiments could be performed at [OH](0) = approximately 4-20 ppm thereby minimizing secondary reactions. OH was produced rapidly from the dissociations of either CH(3)OH or NH(2)OH (hydroxylamine). A mechanism was then used to obtain profile fits that agreed with the experiment to within <+/-5%. The derived Arrhenius expressions, in units of cm(3) molecule(-1) s(-1) are: k(1) = (1.03 +/- 0.24) x 10(-10) exp(-7212 +/- 417 K/T) for 1509-2362 K and k(2) = (10.2 +/- 5.8) x 10(-10) exp(-7411 +/- 871 K/T) for 1463-1931 K. The present study is the first ever direct measurement for reaction (1) at temperatures >1275 K while the present results extend the temperature range for (2) by approximately 700 K. These values are compared with earlier determinations and with recent theoretical calculations. The calculations agree with the present data for both reactions to within +/-10% over the entire T-range.
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Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, IL 60439, USA
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Srinivasan NK, Su MC, Sutherland JW, Michael JV. Reflected Shock Tube Studies of High-Temperature Rate Constants for CH3 + O2, H2CO + O2, and OH + O2. J Phys Chem A 2005; 109:7902-14. [PMID: 16834172 DOI: 10.1021/jp0581330] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The reflected shock tube technique with multipass absorption spectrometric detection of OH-radicals at 308 nm, corresponding to a total path length of approximately 2.8 m, has been used to study the reaction CH3 + O2 CH2O + OH. Experiments were performed between 1303 and 2272 K, using ppm quantities of CH3I (methyl source) and 5-10% O2, diluted with Kr as the bath gas at test pressures less than 1 atm. We have also reanalyzed our earlier ARAS measurements for the atomic channel (CH3 + O2 --> CH3O + O) and have compared both these results with other earlier studies to derive a rate expression of the Arrhenius form. The derived expressions, in units of cm3 molecule(-1) s(-1), are k = 3.11 x 10(-13) exp(-4953 K/T) over the T-range 1237-2430 K, for the OH-channel, and k = 1.253 x 10(-11) exp(-14241 K/T) over the T-range 1250-2430 K, for the O-atom channel. Since CH2O is a major product in both reactions, reliable rates for the reaction CH2O + O2 --> HCO + HO2 could be derived from [OH]t and [O]t experiments over the T-range 1587-2109 K. The combined linear least-squares fit result, k = 1.34 x 10(-8) exp(-26883 K/T) cm3 molecule(-1) s(-1), and a recent VTST calculation clearly overlap within the uncertainties in both studies. Finally, a high sensitivity for the reaction OH + O2 --> HO2 + O was noted at high temperature in the O-atom data set simulations. The values for this obtained by fitting the O-atom data sets at later times (approximately 1.2 ms) again follow the Arrhenius form, k = 2.56 x 10(-10) exp(-24145 K/T) cm3 molecule(-1) s(-1), over the T-range, 1950-2100 K.
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Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Srinivasan NK, Su MC, Sutherland JW, Michael JV. Reflected Shock Tube Studies of High-Temperature Rate Constants for OH + CH4 → CH3 + H2O and CH3 + NO2 → CH3O + NO. J Phys Chem A 2005; 109:1857-63. [PMID: 16833517 DOI: 10.1021/jp040679j] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reflected shock tube technique with multipass absorption spectrometric detection of OH radicals at 308 nm has been used to study the reactions OH + CH(4) --> CH(3) + H(2)O and CH(3) + NO(2) --> CH(3)O + NO. Over the temperature range 840-2025 K, the rate constants for the first reaction can be represented by the Arrhenius expression k = (9.52 +/- 1.62) x 10(-11) exp[(-4134 +/- 222 K)/T] cm(3) molecule(-1) s(-1). Since this reaction is important in both combustion and atmospheric chemistry, there have been many prior investigations with a variety of techniques. The present results extend the temperature range by 500 K and have been combined with the most accurate earlier studies to derive an evaluation over the extended temperature range 195-2025 K. A three-parameter expression describes the rate behavior over this temperature range, k = (1.66 x 10(-18))T(2.182) exp[(-1231 K)/T] cm(3) molecule(-1) s(-1). Previous theoretical studies are discussed, and the present evaluation is compared to earlier theoretical estimates. Since CH(3) radicals are a product of the reaction and could cause secondary perturbations in rate constant determinations, the second reaction was studied by OH radical production from the fast reactions CH(3)O --> CH(2)O + H and H + NO(2) --> OH + NO. The measured rate constant is 2.26 x 10(-11) cm(3) molecule(-1) s(-1) and is not dependent on temperature from 233 to 1700 K within experimental error.
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Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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Michael JV, Fisher JR, Bowman JM, Sun Q. Theoretical and Experimental Rate Constants for Two Isotopic Modifications of the Reaction H + H2. Science 1990; 249:269-71. [PMID: 17750111 DOI: 10.1126/science.249.4966.269] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Theoretical rate constants for two isotopic modifications of the simplest possible chemical reaction, namely, H + D(2) --> HD + D and D + H(2) --> HD + H, are presented. Experimental results, which have previously been obtained in the higher temperature regime by a shock tube technique, are combined with lower temperature results to give an experimental determination of the rate behavior over the large temperature range approximately 200 to 2000 K. It is now possible to assess the accuracy of ab initio potential energy surface calculations and to judge theoretical chemical kinetic methods.
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