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Li Z, Yang X, Fu R, Wu Z, Xu S, Jiao J, Qian M, Zhang L, Wu C, Xie T, Yao J, Wu Z, Li W, Ma G, You Y, Chen Y, Zhang HK, Cheng Y, Tang X, Wu P, Lian G, Wei H, Zhao J, Xu J, Ai L, Siwko S, Wang Y, Ding J, Song G, Luo J, Liu M, Xiao J. Kisspeptin-10 binding to Gpr54 in osteoclasts prevents bone loss by activating Dusp18-mediated dephosphorylation of Src. Nat Commun 2024; 15:1300. [PMID: 38346942 PMCID: PMC10861593 DOI: 10.1038/s41467-024-44852-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 01/05/2024] [Indexed: 02/15/2024] Open
Abstract
Osteoclasts are over-activated as we age, which results in bone loss. Src deficiency in mice leads to severe osteopetrosis due to a functional defect in osteoclasts, indicating that Src function is essential in osteoclasts. G-protein-coupled receptors (GPCRs) are the targets for ∼35% of approved drugs but it is still unclear how GPCRs regulate Src kinase activity. Here, we reveal that GPR54 activation by its natural ligand Kisspeptin-10 (Kp-10) causes Dusp18 to dephosphorylate Src at Tyr 416. Mechanistically, Gpr54 recruits both active Src and the Dusp18 phosphatase at its proline/arginine-rich motif in its C terminus. We show that Kp-10 binding to Gpr54 leads to the up-regulation of Dusp18. Kiss1, Gpr54 and Dusp18 knockout mice all exhibit osteoclast hyperactivation and bone loss, and Kp-10 abrogated bone loss by suppressing osteoclast activity in vivo. Therefore, Kp-10/Gpr54 is a promising therapeutic target to abrogate bone resorption by Dusp18-mediated Src dephosphorylation.
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Affiliation(s)
- Zhenxi Li
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China.
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China.
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China.
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA.
| | - Xinghai Yang
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Ruifeng Fu
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Zhipeng Wu
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Shengzhao Xu
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Jian Jiao
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Ming Qian
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Long Zhang
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
| | - Chunbiao Wu
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Tianying Xie
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Jiqiang Yao
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Zhixiang Wu
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Wenjun Li
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Guoli Ma
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yu You
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yihua Chen
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Han-Kun Zhang
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yiyun Cheng
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Xiaolong Tang
- School of Biomedical Sciences, Hunan University, Changsha, 410082, China
| | - Pengfei Wu
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Gewei Lian
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215, USA
| | - Haifeng Wei
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Jian Zhao
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
| | - Jianrong Xu
- Academy of Integrative Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 201203, China
| | - Lianzhong Ai
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
| | - Stefan Siwko
- Department of Translational Medical Sciences, Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX, USA
| | - Yue Wang
- Shanghai Key Lab of Cell Engineering; Translational Medicine Research Center, Naval Medical University, Shanghai, 200433, China
| | - Jin Ding
- Clinical Cancer Institute, Center for Translational Medicine, Naval Medical University, Shanghai, 200433, China
| | - Gaojie Song
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Jian Luo
- Yangzhi Rehabilitation Hospital (Shanghai Sunshine Rehabilitation Center), Tongji University School of Medicine, Shanghai, China
| | - Mingyao Liu
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Jianru Xiao
- Institute of Orthopedic Biomedical and Device Innovation, School of Health Science and Engineering, University of Shanghai for Science and Technology, Shanghai, 200093, China
- Institute of Orthopedics, Department of Orthopedic Oncology, Shanghai Changzheng Hospital, Naval Medical University, Shanghai, 200003, China
- East China Normal University and Shanghai Changzheng Hospital Joint Research Center for Orthopedic Oncology, Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
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Jameson KG, Kazmi SA, Son C, Mazdeyasnan D, Leshan E, Vuong HE, Paramo J, Lopez-Romero A, Yang L, Schweizer FE, Hsiao EY. Vagal interoception of microbial metabolites from the small intestinal lumen. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572257. [PMID: 38187610 PMCID: PMC10769238 DOI: 10.1101/2023.12.18.572257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The vagus nerve is proposed to enable communication between the gut microbiome and brain, but activity-based evidence is lacking. Herein, we assess the extent of gut microbial influences on afferent vagal activity and metabolite signaling mechanisms involved. We find that mice reared without microbiota (germ-free, GF) exhibit decreased vagal afferent tone relative to conventionally colonized mice (specific pathogen-free, SPF), which is reversed by colonization with SPF microbiota. Perfusing non-absorbable antibiotics (ABX) into the small intestine of SPF mice, but not GF mice, acutely decreases vagal activity, which is restored upon re-perfusion with bulk lumenal contents or sterile filtrates from the small intestine and cecum of SPF, but not GF, mice. Of several candidates identified by metabolomic profiling, microbiome-dependent short-chain fatty acids, bile acids, and 3-indoxyl sulfate stimulate vagal activity with varied response kinetics, which is blocked by co-perfusion of pharmacological antagonists of FFAR2, TGR5, and TRPA1, respectively, into the small intestine. At the single-unit level, serial perfusion of each metabolite class elicits more singly responsive neurons than dually responsive neurons, suggesting distinct neuronal detection of different microbiome- and macronutrient-dependent metabolites. Finally, microbial metabolite-induced increases in vagal activity correspond with activation of neurons in the nucleus of the solitary tract, which is also blocked by co-administration of their respective receptor antagonists. Results from this study reveal that the gut microbiome regulates select metabolites in the intestinal lumen that differentially activate chemosensory vagal afferent neurons, thereby enabling microbial modulation of interoceptive signals for gut-brain communication. HIGHLIGHTS Microbiota colonization status modulates afferent vagal nerve activityGut microbes differentially regulate metabolites in the small intestine and cecumSelect microbial metabolites stimulate vagal afferents with varied response kineticsSelect microbial metabolites activate vagal afferent neurons and brainstem neurons via receptor-dependent signaling.
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Chen Y, Cao B, Zheng W, Xu T. ACKR4a induces autophagy to block NF-κB signaling and apoptosis to facilitate Vibrio harveyi infection. iScience 2023; 26:106105. [PMID: 36843837 PMCID: PMC9947386 DOI: 10.1016/j.isci.2023.106105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2022] [Revised: 12/03/2022] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Autophagy and apoptosis are two recognized mechanisms of resistance to bacterial invasion. However, bacteria have likewise evolved the ability to evade immunity. In this study, we identify ACKR4a, a member of an atypical chemokine receptor family, as a suppressor of the NF-κB pathway, which cooperates with Beclin-1 to induce autophagy to inhibit NF-κB signaling and block apoptosis, facilitating Vibrio harveyi infection. Mechanistically, V. harveyi-induced Ap-1 activates ACKR4a transcription and expression. ACKR4a forms a complex with Beclin-1 and MyD88, respectively, inducing autophagy and transporting MyD88 into the lysosome for degradation to suppress inflammatory cytokine production. Meanwhile, ACKR4a-induced autophagy blocks apoptosis by inhibiting caspase8. This study proves for the first time that V. harveyi uses both autophagy and apoptosis to evade innate immunity, suggesting that V. harveyi has evolved the ability to against fish immunity.
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Affiliation(s)
- Ya Chen
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Baolan Cao
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Weiwei Zheng
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Tianjun Xu
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Corresponding author
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4
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Duval V, Alayrac P, Silvestre JS, Levoye A. Emerging Roles of the Atypical Chemokine Receptor 3 (ACKR3) in Cardiovascular Diseases. Front Endocrinol (Lausanne) 2022; 13:906586. [PMID: 35846294 PMCID: PMC9276939 DOI: 10.3389/fendo.2022.906586] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/27/2022] [Indexed: 11/14/2022] Open
Abstract
Chemokines, and their receptors play a crucial role in the pathophysiology of cardiovascular diseases (CVD). Chemokines classically mediate their effects by binding to G-protein-coupled receptors. The discovery that chemokines can also bind to atypical chemokine receptors (ACKRs) and initiate alternative signaling pathways has changed the paradigm regarding chemokine-related functions. Among these ACKRs, several studies have highlighted the exclusive role of ACKR3, previously known as C-X-C chemokine receptor type 7 (CXCR7), in CVD. Indeed, ACKR3 exert atheroprotective, cardioprotective and anti-thrombotic effects through a wide range of cells including endothelial cells, platelets, inflammatory cells, fibroblasts, vascular smooth muscle cells and cardiomyocytes. ACKR3 functions as a scavenger receptor notably for the pleiotropic chemokine CXCL12, but also as a activator of different pathways such as β-arrestin-mediated signaling or modulator of CXCR4 signaling through the formation of ACKR3-CXCR4 heterodimers. Hence, a better understanding of the precise roles of ACKR3 may pave the way towards the development of novel and improved therapeutic strategies for CVD. Here, we summarize the structural determinant characteristic of ACKR3, the molecules targeting this receptor and signaling pathways modulated by ACKR3. Finally, we present and discuss recent findings regarding the role of ACKR3 in CVD.
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Affiliation(s)
- Vincent Duval
- Université Paris Cité, Institut National de la Santé Et Recherche Médicale (INSERM), Paris Cardiovascular Research Center PARCC, Paris, France
| | - Paul Alayrac
- Université Paris Cité, Institut National de la Santé Et Recherche Médicale (INSERM), Paris Cardiovascular Research Center PARCC, Paris, France
| | - Jean-Sébastien Silvestre
- Université Paris Cité, Institut National de la Santé Et Recherche Médicale (INSERM), Paris Cardiovascular Research Center PARCC, Paris, France
| | - Angélique Levoye
- Université Paris Cité, Institut National de la Santé Et Recherche Médicale (INSERM), Paris Cardiovascular Research Center PARCC, Paris, France
- UFR Santé Médecine Biologie Humaine, Université Sorbonne Paris Nord, Bobigny, France
- *Correspondence: Angélique Levoye,
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5
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Hostrup M, Onslev J. The beta 2 -adrenergic receptor - a re-emerging target to combat obesity and induce leanness? J Physiol 2021; 600:1209-1227. [PMID: 34676534 DOI: 10.1113/jp281819] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 10/12/2021] [Indexed: 12/25/2022] Open
Abstract
Treatment of obesity with repurposed or novel drugs is an expanding research field. One approach is to target beta2 -adrenergic receptors because they regulate the metabolism and phenotype of adipose and skeletal muscle tissue. Several observations support a role for the beta2 -adrenergic receptor in obesity. Specific human beta2 -adrenergic receptor polymorphisms are associated with body composition and obesity, for which the Gln27Glu polymorphism is associated with obesity, while the Arg16Gly polymorphism is associated with lean mass in men and the development of obesity in specific populations. Individuals with obesity also have lower abundance of beta2 -adrenergic receptors in adipose tissue and are less sensitive to catecholamines. In addition, studies in livestock and rodents demonstrate that selective beta2 -agonists induce a so-called 'repartitioning effect' characterized by muscle accretion and reduced fat deposition. In humans, beta2 -agonists dose-dependently increase resting metabolic rate by 10-50%. And like that observed in other mammals, only a few weeks of treatment with beta2 -agonists increases muscle mass and reduces fat mass in young healthy individuals. Beta2 -agonists also exert beneficial effects on body composition when used concomitantly with training and act additively to increase muscle strength and mass during periods with resistance training. Thus, the beta2 -adrenergic receptor seems like an attractive target in the development of anti-obesity drugs. However, future studies need to verify the long-term efficacy and safety of beta2 -agonists in individuals with obesity, particularly in those with comorbidities.
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Affiliation(s)
- Morten Hostrup
- Section of Integrative Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
| | - Johan Onslev
- Section of Molecular Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark
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6
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Onaran HO, Costa T. Conceptual and experimental issues in biased agonism. Cell Signal 2021; 82:109955. [PMID: 33607257 DOI: 10.1016/j.cellsig.2021.109955] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 01/20/2021] [Accepted: 02/14/2021] [Indexed: 12/31/2022]
Abstract
In this review, we discuss the theoretical and experimental foundations for assessing agonism in the context of signalling bias in GPCRs. We show that the formulation of efficacy in classical receptor theory and the definition of ligand-induced allosteric effect in chemical thermodynamics are coincident measures of agonism, only if we recognize that the classical model cannot be considered as a mechanistic description of the physicochemical events underlying ligand-receptor signalling. It represents instead a mathematical tool, fortuitously capable of extracting efficacy information from concentration-dependent functional data, where both ligand-dependent and ligand-independent information are present. We also assert that dissecting efficacy from affinity, as originally advocated in classical theory, is imperative for understanding the molecular property underlying agonism, and the biased agonism that leads to preferential formation of diverse GPCR-transducer complexes. Finally, we argue that beyond the assumed translational value of functional selectivity (i.e. signalling bias), the identification of ligands with true bias of efficacy is of fundamental importance for unravelling the conformational space that determines the complex functional chemistry of GPCRs.
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Affiliation(s)
- H Ongun Onaran
- Ankara University, Faculty of Medicine, Department of Pharmacology, Molecular Biology and Technology Development Unit, Ankara, Turkey.
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7
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Choi BK, Lee HW. The Murine CD137/CD137 Ligand Signalosome: A Signal Platform Generating Signal Complexity. Front Immunol 2020; 11:553715. [PMID: 33362756 PMCID: PMC7758191 DOI: 10.3389/fimmu.2020.553715] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 11/06/2020] [Indexed: 12/21/2022] Open
Abstract
CD137, a member of the TNFR family, is a costimulatory receptor, and CD137L, a member of the TNF family, is its ligand. Studies using CD137- and CD137L-deficient mice and antibodies against CD137 and CD137L have revealed the diverse and paradoxical effects of these two proteins in various cancers, autoimmunity, infections, and inflammation. Both their cellular diversity and their spatiotemporal expression patterns indicate that they mediate complex immune responses. This intricacy is further enhanced by the bidirectional signal transduction events that occur when these two proteins interact in various types of immune cells. Here, we review the biology of murine CD137/CD137L, particularly, the complexity of their proximal signaling pathways, and speculate on their roles in immune responses.
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Affiliation(s)
- Beom K Choi
- Biomedicine Production Branch, Program for Immunotherapy Research, National Cancer Center, Goyang, South Korea
| | - Hyeon-Woo Lee
- Department of Pharmacology, School of Dentistry, Graduate School, Institute of Oral Biology, Kyung Hee University, Seoul, South Korea
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8
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Tsentsevitsky A, Nurullin L, Tyapkina O, Bukharaeva E. Sympathomimetics regulate quantal acetylcholine release at neuromuscular junctions through various types of adrenoreceptors. Mol Cell Neurosci 2020; 108:103550. [PMID: 32890729 DOI: 10.1016/j.mcn.2020.103550] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/26/2020] [Accepted: 08/27/2020] [Indexed: 01/01/2023] Open
Abstract
The studies of the interaction between the sympathetic and motor nervous systems are extremely relevant due to therapy for many neurodegenerative and cardiovascular disorders involving adrenergic compounds. Evidences indicate close contact between sympathetic varicosities and neuromuscular synapses. This raises questions about the effects of catecholamines on synaptic transmission. The currently available information is contradictory, and the types of adrenoreceptors responsible for modulation of neurotransmitter release have not been identified in mammalian neuromuscular synapses. Our results have shown that the α1A, α1B, α2A, α2B, α2C, and β1 adrenoreceptor subtypes are expressed in mouse diaphragm muscle containing neuromuscular synapses and sympathetic varicosities. Pharmacological stimulation of adrenoreceptors affects both spontaneous and evoked acetylcholine quantal secretion. Agonists of the α1, α2 and β1 adrenoreceptors decrease spontaneous release. Activation of the α2 and β1 adrenoreceptors reduces the number of acetylcholine quanta released in response to a nerve stimulus (quantal content), but an agonist of the β2 receptors increases quantal content. Activation of α2 and β2 adrenoreceptors alters the kinetics of acetylcholine quantal release by desynchronizing the neurosecretory process. Specific blockers of these receptors eliminate the effects of the specific agonists. The action of blockers on quantal acetylcholine secretion indicates possible action of endogenous catecholamines on neuromuscular transmission. Elucidating the molecular mechanisms by which clinically utilized adrenomimetics and adrenoblockers regulate synaptic vesicle release at the motor axon terminal will lead to the creation of improved and safer sympathomimetics for the treatment of various neurodegenerative diseases with synaptic defects.
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Affiliation(s)
- Andrei Tsentsevitsky
- Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RAS, PB 30, Kazan 420111, Russia
| | - Leniz Nurullin
- Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RAS, PB 30, Kazan 420111, Russia
| | - Oksana Tyapkina
- Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RAS, PB 30, Kazan 420111, Russia
| | - Ellya Bukharaeva
- Kazan Institute of Biochemistry and Biophysics FRC Kazan Scientific Center of RAS, PB 30, Kazan 420111, Russia.
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9
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Kaya AI, Perry NA, Gurevich VV, Iverson TM. Phosphorylation barcode-dependent signal bias of the dopamine D1 receptor. Proc Natl Acad Sci U S A 2020; 117:14139-14149. [PMID: 32503917 PMCID: PMC7321966 DOI: 10.1073/pnas.1918736117] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Agonist-activated G protein-coupled receptors (GPCRs) must correctly select from hundreds of potential downstream signaling cascades and effectors. To accomplish this, GPCRs first bind to an intermediary signaling protein, such as G protein or arrestin. These intermediaries initiate signaling cascades that promote the activity of different effectors, including several protein kinases. The relative roles of G proteins versus arrestins in initiating and directing signaling is hotly debated, and it remains unclear how the correct final signaling pathway is chosen given the ready availability of protein partners. Here, we begin to deconvolute the process of signal bias from the dopamine D1 receptor (D1R) by exploring factors that promote the activation of ERK1/2 or Src, the kinases that lead to cell growth and proliferation. We found that ERK1/2 activation involves both arrestin and Gαs, while Src activation depends solely on arrestin. Interestingly, we found that the phosphorylation pattern influences both arrestin and Gαs coupling, suggesting an additional way the cells regulate G protein signaling. The phosphorylation sites in the D1R intracellular loop 3 are particularly important for directing the binding of G protein versus arrestin and for selecting between the activation of ERK1/2 and Src. Collectively, these studies correlate functional outcomes with a physical basis for signaling bias and provide fundamental information on how GPCR signaling is directed.
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Affiliation(s)
- Ali I Kaya
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232
| | - Nicole A Perry
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232
| | | | - T M Iverson
- Department of Pharmacology, Vanderbilt University, Nashville, TN 37232;
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232
- Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232
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10
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GRK2-Dependent HuR Phosphorylation Regulates HIF1α Activation under Hypoxia or Adrenergic Stress. Cancers (Basel) 2020; 12:cancers12051216. [PMID: 32413989 PMCID: PMC7281538 DOI: 10.3390/cancers12051216] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 05/09/2020] [Accepted: 05/11/2020] [Indexed: 12/18/2022] Open
Abstract
Adaptation to hypoxia is a common feature in solid tumors orchestrated by oxygen-dependent and independent upregulation of the hypoxia-inducible factor-1α (HIF-1α). We unveiled that G protein-coupled receptor kinase (GRK2), known to be overexpressed in certain tumors, fosters this hypoxic pathway via phosphorylation of the mRNA-binding protein HuR, a central HIF-1α modulator. GRK2-mediated HuR phosphorylation increases the total levels and cytoplasmic shuttling of HuR in response to hypoxia, and GRK2-phosphodefective HuR mutants show defective cytosolic accumulation and lower binding to HIF-1α mRNA in hypoxic Hela cells. Interestingly, enhanced GRK2 and HuR expression correlate in luminal breast cancer patients. GRK2 also promotes the HuR/HIF-1α axis and VEGF-C accumulation in normoxic MCF7 breast luminal cancer cells and is required for the induction of HuR/HIF1-α in response to adrenergic stress. Our results point to a relevant role of the GRK2/HuR/HIF-1α module in the adaptation of malignant cells to tumor microenvironment-related stresses.
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11
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Campos JC, Baehr LM, Ferreira ND, Bozi LHM, Andres AM, Ribeiro MAC, Gottlieb RA, Bodine SC, Ferreira JCB. β 2 -adrenoceptor activation improves skeletal muscle autophagy in neurogenic myopathy. FASEB J 2020; 34:5628-5641. [PMID: 32112488 DOI: 10.1096/fj.201902305r] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 02/03/2020] [Accepted: 02/14/2020] [Indexed: 01/21/2023]
Abstract
β2 -adrenoceptor agonists improve autophagy and re-establish proteostasis in cardiac cells; therefore, suggesting autophagy as a downstream effector of β2 -adrenoceptor signaling pathway. Here, we used the pharmacological and genetic tools to determine the autophagy effect of sustained β2 -adrenoceptor activation in rodents with neurogenic myopathy, which display impaired skeletal muscle autophagic flux. Sustained β2 -adrenoceptor activation using Formoterol (10 μg kg-1 day-1 ), starting at the onset of neurogenic myopathy, prevents disruption of autophagic flux in skeletal muscle 14 days after sciatic nerve constriction. These changes are followed by reduction of the cytotoxic protein levels and increased skeletal muscle cross-sectional area and contractility properties. Of interest, sustained administration of Formoterol at lower concentration (1 μg kg-1 day-1 ) induces similar improvements in skeletal muscle autophagic flux and contractility properties in neurogenic myopathy, without affecting the cross-sectional area. Sustained pharmacological inhibition of autophagy using Chloroquine (50 mg kg-1 day-1 ) abolishes the beneficial effects of β2 -adrenoceptor activation on the skeletal muscle proteostasis and contractility properties in neurogenic myopathy. Further supporting an autophagy mechanism for β2 -adrenoceptor activation, skeletal muscle-specific deletion of ATG7 blunts the beneficial effects of β2 -adrenoceptor on skeletal muscle proteostasis and contractility properties in neurogenic myopathy in mice. These findings suggest autophagy as a critical downstream effector of β2 -adrenoceptor signaling pathway in skeletal muscle.
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Affiliation(s)
- Juliane C Campos
- Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Leslie M Baehr
- Department of Internal Medicine, Endocrinology and Metabolism Division, University of Iowa, Iowa City, IA, USA
| | - Nikolas D Ferreira
- Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Luiz H M Bozi
- Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Allen M Andres
- The Cedars-Sinai Heart Institute and the Barbra Streisand Women's Heart Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Márcio A C Ribeiro
- Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Roberta A Gottlieb
- The Cedars-Sinai Heart Institute and the Barbra Streisand Women's Heart Center, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Sue C Bodine
- Department of Internal Medicine, Endocrinology and Metabolism Division, University of Iowa, Iowa City, IA, USA
| | - Julio C B Ferreira
- Institute of Biomedical Sciences, University of Sao Paulo, Sao Paulo, Brazil
- Department of Chemical & Systems Biology, Stanford University School of Medicine, Stanford, CA, USA
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12
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Jiang QX. Structural Variability in the RLR-MAVS Pathway and Sensitive Detection of Viral RNAs. Med Chem 2019; 15:443-458. [PMID: 30569868 DOI: 10.2174/1573406415666181219101613] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 10/23/2018] [Accepted: 12/12/2018] [Indexed: 12/25/2022]
Abstract
Cells need high-sensitivity detection of non-self molecules in order to fight against pathogens. These cellular sensors are thus of significant importance to medicinal purposes, especially for treating novel emerging pathogens. RIG-I-like receptors (RLRs) are intracellular sensors for viral RNAs (vRNAs). Their active forms activate mitochondrial antiviral signaling protein (MAVS) and trigger downstream immune responses against viral infection. Functional and structural studies of the RLR-MAVS signaling pathway have revealed significant supramolecular variability in the past few years, which revealed different aspects of the functional signaling pathway. Here I will discuss the molecular events of RLR-MAVS pathway from the angle of detecting single copy or a very low copy number of vRNAs in the presence of non-specific competition from cytosolic RNAs, and review key structural variability in the RLR / vRNA complexes, the MAVS helical polymers, and the adapter-mediated interactions between the active RLR / vRNA complex and the inactive MAVS in triggering the initiation of the MAVS filaments. These structural variations may not be exclusive to each other, but instead may reflect the adaptation of the signaling pathways to different conditions or reach different levels of sensitivity in its response to exogenous vRNAs.
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Affiliation(s)
- Qiu-Xing Jiang
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, United States
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13
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Kameritsch P, Kiemer F, Mannell H, Beck H, Pohl U, Pogoda K. PKA negatively modulates the migration enhancing effect of Connexin 43. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:828-838. [PMID: 30769008 DOI: 10.1016/j.bbamcr.2019.02.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 12/22/2022]
Abstract
Connexin 43 (Cx43) expression is associated with an increased cell migration and related changes of the actin cytoskeleton (enhanced filopodia formation). These effects are mediated by the C-terminal cytoplasmic part of Cx43 in a channel-independent manner. Since this part has been shown to interact with a variety of proteins and has multiple phosphorylation sites we analyzed here a potential role of the protein kinase A (PKA) for the Cx43 mediated increase in cell migration. Mutation of the PKA-phosphorylation site (substitution of three serines by alanine or glycine) resulted in a further increase in cell motility compared to wild-type Cx43, but with a loss of directionality. Likewise, cell motility was enhanced by PKA inhibition only in Cx43 expressing cells, while reduced in the presence of the PKA activator forskolin. In contrast, cell motility remained unaffected by stimulation with forskolin in cells expressing Cx43 with the mutated PKA phosphorylation site (Cx43-PKA) as well as in Cx-deficient cells. Moreover, PKA activation resulted in increased binding of PKA and VASP to Cx43 associated with an enhanced phosphorylation of VASP, an important regulatory protein of cell polarity and directed migration. Functionally, we could confirm these results in endothelial cells endogenously expressing Cx43. A Tat-Cx43 peptide containing the PKA phosphorylation site abolished the PKA dependent reduction in endothelial cell migration. Our results indicate that PKA dependent phosphorylation of Cx43 modulates cell motility and plays a pivotal role in regulating directed cell migration.
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Affiliation(s)
- Petra Kameritsch
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Biedersteiner Str. 29, 80802 München, Germany.
| | - Felizitas Kiemer
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany.
| | - Hanna Mannell
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany.
| | - Heike Beck
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany.
| | - Ulrich Pohl
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Biedersteiner Str. 29, 80802 München, Germany; Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Str. 17, 81377 München, Germany.
| | - Kristin Pogoda
- Walter Brendel Centre of Experimental Medicine, Ludwig-Maximilians-Universität München and Munich University Hospital, Großhaderner Str. 9, 82152 Planegg, Martinsried, Germany; DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Biedersteiner Str. 29, 80802 München, Germany.
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14
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Perkovska S, Méjean C, Ayoub MA, Li J, Hemery F, Corbani M, Laguette N, Ventura MA, Orcel H, Durroux T, Mouillac B, Mendre C. V 1b vasopressin receptor trafficking and signaling: Role of arrestins, G proteins and Src kinase. Traffic 2018; 19:58-82. [PMID: 29044966 DOI: 10.1111/tra.12535] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 10/13/2017] [Accepted: 10/13/2017] [Indexed: 11/29/2022]
Abstract
The signaling pathway of G protein-coupled receptors is strongly linked to their trafficking profile. Little is known about the molecular mechanisms involved in the vasopressin receptor V1b subtype (V1b R) trafficking and its impact on receptor signaling and regulation. For this purpose, we investigated the role of β-arrestins in receptor desensitization, internalization and recycling and attempted to dissect the V1b R-mediated MAP kinase pathway. Using MEF cells Knocked-out for β-arrestins 1 and 2, we demonstrated that both β-arrestins 1 and 2 play a fundamental role in internalization and recycling of V1b R with a rapid and transient V1b R-β-arrestin interaction in contrast to a slow and long-lasting β-arrestin recruitment of the V2 vasopressin receptor subtype (V2 R). Using V1b R-V2 R chimeras and V1b R C-terminus truncations, we demonstrated the critical role of the V1b R C-terminus in its interaction with β-arrestins thereby regulating the receptor internalization and recycling kinetics in a phosphorylation-independent manner. In parallel, V1b R MAP kinase activation was dependent on arrestins and Src-kinase but independent on G proteins. Interestingly, Src interacted with hV1b R at basal state and dissociated when receptor internalization occurred. Altogether, our data describe for the first time the trafficking profile and MAP kinase pathway of V1b R involving both arrestins and Src kinase family.
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Affiliation(s)
- Sanja Perkovska
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Catherine Méjean
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Mohammed Akli Ayoub
- Biology Department, College of Science, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Juan Li
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Floriane Hemery
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Maithé Corbani
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Nadine Laguette
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Maria-Angeles Ventura
- INSERM, U1016, Institut Cochin, Paris, France.,CNRS, UMR 8104, Paris, France.,Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Hélène Orcel
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Thierry Durroux
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Bernard Mouillac
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
| | - Christiane Mendre
- Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 5203, Institut de Génomique Fonctionnelle (IGF), Montpellier, France.,Institut National de la Santé et de la Recherche Médicale (INSERM), U1191, Montpellier, France.,Université de Montpellier, Montpellier, France
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15
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Civciristov S, Ellisdon AM, Suderman R, Pon CK, Evans BA, Kleifeld O, Charlton SJ, Hlavacek WS, Canals M, Halls ML. Preassembled GPCR signaling complexes mediate distinct cellular responses to ultralow ligand concentrations. Sci Signal 2018; 11:11/551/eaan1188. [PMID: 30301787 DOI: 10.1126/scisignal.aan1188] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest class of cell surface signaling proteins, participate in nearly all physiological processes, and are the targets of 30% of marketed drugs. Typically, nanomolar to micromolar concentrations of ligand are used to activate GPCRs in experimental systems. We detected GPCR responses to a wide range of ligand concentrations, from attomolar to millimolar, by measuring GPCR-stimulated production of cyclic adenosine monophosphate (cAMP) with high spatial and temporal resolution. Mathematical modeling showed that femtomolar concentrations of ligand activated, on average, 40% of the cells in a population provided that a cell was activated by one to two binding events. Furthermore, activation of the endogenous β2-adrenergic receptor (β2AR) and muscarinic acetylcholine M3 receptor (M3R) by femtomolar concentrations of ligand in cell lines and human cardiac fibroblasts caused sustained increases in nuclear translocation of extracellular signal-regulated kinase (ERK) and cytosolic protein kinase C (PKC) activity, respectively. These responses were spatially and temporally distinct from those that occurred in response to higher concentrations of ligand and resulted in a distinct cellular proteomic profile. This highly sensitive signaling depended on the GPCRs forming preassembled, higher-order signaling complexes at the plasma membrane. Recognizing that GPCRs respond to ultralow concentrations of neurotransmitters and hormones challenges established paradigms of drug action and provides a previously unappreciated aspect of GPCR activation that is quite distinct from that typically observed with higher ligand concentrations.
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Affiliation(s)
- Srgjan Civciristov
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Andrew M Ellisdon
- Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Ryan Suderman
- Theoretical Biology and Biophysics Group, Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Cindy K Pon
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Bronwyn A Evans
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Oded Kleifeld
- Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia.,Faculty of Biology, Technion-Israel Institute of Technology, Technion City, Haifa 3200003, Israel
| | - Steven J Charlton
- Cell Signalling Research Group, School of Life Sciences, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, UK.,Excellerate Bioscience Ltd, MediCity, Nottingham NG90 6BH, UK
| | - William S Hlavacek
- Theoretical Biology and Biophysics Group, Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Meritxell Canals
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Michelle L Halls
- Drug Discovery Biology Theme, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia.
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16
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An operational model for GPCR homodimers and its application in the analysis of biased signaling. Drug Discov Today 2018; 23:1591-1595. [DOI: 10.1016/j.drudis.2018.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/28/2018] [Accepted: 04/05/2018] [Indexed: 11/23/2022]
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17
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Wang W, Qiao Y, Li Z. New Insights into Modes of GPCR Activation. Trends Pharmacol Sci 2018; 39:367-386. [DOI: 10.1016/j.tips.2018.01.001] [Citation(s) in RCA: 129] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/03/2018] [Accepted: 01/08/2018] [Indexed: 12/22/2022]
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18
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Lack of beta-arrestin signaling in the absence of active G proteins. Nat Commun 2018; 9:341. [PMID: 29362459 PMCID: PMC5780443 DOI: 10.1038/s41467-017-02661-3] [Citation(s) in RCA: 257] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 12/18/2017] [Indexed: 02/06/2023] Open
Abstract
G protein-independent, arrestin-dependent signaling is a paradigm that broadens the signaling scope of G protein-coupled receptors (GPCRs) beyond G proteins for numerous biological processes. However, arrestin signaling in the collective absence of functional G proteins has never been demonstrated. Here we achieve a state of “zero functional G” at the cellular level using HEK293 cells depleted by CRISPR/Cas9 technology of the Gs/q/12 families of Gα proteins, along with pertussis toxin-mediated inactivation of Gi/o. Together with HEK293 cells lacking β-arrestins (“zero arrestin”), we systematically dissect G protein- from arrestin-driven signaling outcomes for a broad set of GPCRs. We use biochemical, biophysical, label-free whole-cell biosensing and ERK phosphorylation to identify four salient features for all receptors at “zero functional G”: arrestin recruitment and internalization, but—unexpectedly—complete failure to activate ERK and whole-cell responses. These findings change our understanding of how GPCRs function and in particular of how they activate ERK1/2. Arrestins terminate signaling from GPCRs, but several lines of evidence suggest that they are also able to transduce signals independently of G proteins. Here, the authors systematically ablate G proteins in cell lines, and show that arrestins are unable to act as genuine signal initiators.
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19
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Abstract
Orexin/hypocretin peptide (orexin-A and orexin-B) signaling is believed to take place via the two G-protein-coupled receptors (GPCRs), named OX1 and OX2 orexin receptors, as described in the previous chapters. Signaling of orexin peptides has been investigated in diverse endogenously orexin receptor-expressing cells - mainly neurons but also other types of cells - and in recombinant cells expressing the receptors in a heterologous manner. Findings in the different systems are partially convergent but also indicate cellular background-specific signaling. The general picture suggests an inherently high degree of diversity in orexin receptor signaling.In the current chapter, I present orexin signaling on the cellular and molecular levels. Discussion of the connection to (potential) physiological orexin responses is only brief since these are in focus of other chapters in this book. The same goes for the post-synaptic signaling mechanisms, which are dealt with in Burdakov: Postsynaptic actions of orexin. The current chapter is organized according to the tissue type, starting from the central nervous system. Finally, receptor signaling pathways are discussed across tissues, cell types, and even species.
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Affiliation(s)
- Jyrki P Kukkonen
- Biochemistry and Cell Biology, Department of Veterinary Biosciences, University of Helsinki, POB 66, FIN-00014, Helsinki, Finland.
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20
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Jiang SH, Li J, Dong FY, Yang JY, Liu DJ, Yang XM, Wang YH, Yang MW, Fu XL, Zhang XX, Li Q, Pang XF, Huo YM, Li J, Zhang JF, Lee HY, Lee SJ, Qin WX, Gu JR, Sun YW, Zhang ZG. Increased Serotonin Signaling Contributes to the Warburg Effect in Pancreatic Tumor Cells Under Metabolic Stress and Promotes Growth of Pancreatic Tumors in Mice. Gastroenterology 2017; 153:277-291.e19. [PMID: 28315323 DOI: 10.1053/j.gastro.2017.03.008] [Citation(s) in RCA: 175] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 02/21/2017] [Accepted: 03/08/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Desmoplasia and poor vascularity cause severe metabolic stress in pancreatic ductal adenocarcinomas (PDACs). Serotonin (5-HT) is a neuromodulator with neurotransmitter and neuroendocrine functions that contributes to tumorigenesis. We investigated the role of 5-HT signaling in the growth of pancreatic tumors. METHODS We measured the levels of proteins that regulate 5-HT synthesis, packaging, and degradation in pancreata from KrasG12D/+/Trp53R172H/+/Pdx1-Cre (KPC) mice, which develop pancreatic tumors, as well as in PDAC cell lines and a tissue microarray containing 81 human PDAC samples. We also analyzed expression levels of proteins involved in 5-HT synthesis and degradation by immunohistochemical analysis of a tissue microarray containing 311 PDAC specimens, and associated expression levels with patient survival times. 5-HT level in 14 matched PDAC tumor and non-tumor tissues were analyzed by ELISA. PDAC cell lines were incubated with 5-HT and cell survival and apoptosis were measured. We analyzed expression of the 5-HT receptor HTR2B in PDAC cells and effects of receptor agonists and antagonists, as well as HTR2B knockdown with small hairpin RNAs. We determined the effects of 5-HT stimulation on gene expression profiles of BxPC-3 cells. Regulation of glycolysis by 5-HT signaling via HTR2B was assessed by immunofluorescence and immunoprecipitation analyses, as well as by determination of the extracellular acid ratio, glucose consumption, and lactate production. Primary PDACs, with or without exposure to SB204741 (a selective antagonist of HTR2B), were grown as xenograft tumors in mice, and SB204741 was administered to tumor-bearing KPC mice; tumor growth and metabolism were measured by imaging analyses. RESULTS In immunohistochemical analysis of a tissue microarray of PDAC specimens, increased levels of TPH1 and decreased level of MAOA, which regulate 5-HT synthesis and degradation, correlated with stage and size of PDACs and shorter patient survival time. We found levels of 5-HT to be increased in human PDAC tissues compared with non-tumor pancreatic tissues, and PDAC cell lines compared with non-transformed pancreatic cells. Incubation of PDAC cell lines with 5-HT increased proliferation and prevented apoptosis. Agonists of HTR2B, but not other 5-HT receptors, promoted proliferation and prevented apoptosis of PDAC cells. Knockdown of HTR2B in PDAC cells, or incubation of cells with HTR2B inhibitors, reduced their growth as xenograft tumors in mice. We observed a correlation between 5-HT and glycolytic flux in PDAC cells; levels of metabolic enzymes involved in glycolysis, the phosphate pentose pathway, and hexosamine biosynthesis pathway increased significantly in PDAC cells following 5-HT stimulation. 5-HT stimulation led to formation of the HTR2B-LYN-p85 complex, which increased PI3K-Akt-mTOR signaling and the Warburg effect by increasing protein levels of MYC and HIF1A. Administration of SB204741 to KPC mice slowed growth and metabolism of established pancreatic tumors and prolonged survival of the mice. CONCLUSIONS Human PDACs have increased levels of 5-HT, and PDAC cells increase expression of its receptor, HTR2B. These increases allow for tumor glycolysis under metabolic stress and promote growth of pancreatic tumors and PDAC xenograft tumors in mice.
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Affiliation(s)
- Shu-Heng Jiang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China; Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Jun Li
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Fang-Yuan Dong
- Department of Gastroenterology, Shanghai Key Laboratory of Clinical Geriatric Medicine, Huadong Hospital, Shanghai, PR China
| | - Jian-Yu Yang
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - De-Jun Liu
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Xiao-Mei Yang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Ya-Hui Wang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Min-Wei Yang
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Xue-Liang Fu
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Xiao-Xin Zhang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Qing Li
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Xiu-Feng Pang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, China
| | - Yan-Miao Huo
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Jiao Li
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Jun-Feng Zhang
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Ho-Young Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Su-Jae Lee
- Department of Life Science, Research Institute for Nature Sciences, Hanyang University, Seoul, Republic of Korea
| | - Wen-Xin Qin
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Jian-Ren Gu
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China
| | - Yong-Wei Sun
- Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P.R. China.
| | - Zhi-Gang Zhang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai, P.R. China.
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21
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Posma JJN, Posthuma JJ, Spronk HMH. Coagulation and non-coagulation effects of thrombin. J Thromb Haemost 2016; 14:1908-1916. [PMID: 27513692 DOI: 10.1111/jth.13441] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 07/08/2016] [Indexed: 01/06/2023]
Abstract
Thrombin is a multifunctional serine protease produced from prothrombin, and is a key regulator in hemostatic and non-hemostatic processes. It is the main effector protease in primary hemostasis by activating platelets, and plays a key role in secondary hemostasis. Besides its well-known functions in hemostasis, thrombin also plays a role in various non-hemostatic biological and pathophysiologic processes, predominantly mediated through activation of protease-activated receptors (PARs). Depending on several factors, such as the concentration of thrombin, the duration of activation, the location of PARs, the presence of coreceptors, and the formation of PAR heterodimers, activation of the receptor by thrombin can induce different cellular responses. Moreover, thrombin can have opposing effects in the same cell; it can induce both inflammatory and anti-inflammatory signals. Owing to the complexity of thrombin's signal transduction pathways, the exact mechanism behind the dichotomy of thrombin is yet still unknown. In this review, we highlight the hemostatic and non-hemostatic functions of thrombin, and specifically focus on the non-hemostatic dual role of thrombin under various conditions and in relation to cardiovascular disease.
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Affiliation(s)
- J J N Posma
- Departments of Internal Medicine and Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands
| | - J J Posthuma
- Departments of Internal Medicine and Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands
| | - H M H Spronk
- Departments of Internal Medicine and Biochemistry, Cardiovascular Research Institute Maastricht, Maastricht University Medical Center, Maastricht, the Netherlands.
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22
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Odnoshivkina YG, Sytchev VI, Petrov AM. Cholesterol regulates contractility and inotropic response to β2-adrenoceptor agonist in the mouse atria: Involvement of G i-protein-Akt-NO-pathway. J Mol Cell Cardiol 2016; 107:27-40. [PMID: 27170493 DOI: 10.1016/j.yjmcc.2016.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/03/2016] [Accepted: 05/04/2016] [Indexed: 10/21/2022]
Abstract
Majority of cardiac β2-adrenoceptors is located in cholesterol-rich microdomains. Here, we have investigated the underlying mechanisms by which a slight to moderate cholesterol depletion with methyl-β-cyclodextrin (MβCD, 1 and 5mM) interferes with contractility and inotropic effect of β2-adrenergic agonist (fenoterol, 50μM) in the mouse atria. Treatment with MβCD itself increased amplitude of Ca2+ transient but did not change the contraction amplitude due to a clamping action of elevated NO. Cholesterol depletion significantly attenuated the positive inotropic response to fenoterol which is accompanied by increase in NO generation and decrease in Ca2+ transient. Influence of 1mM MβCD on the fenoterol-driven changes in both contractility and NO level was strongly attenuated by inhibition of Gi-protein (pertussis toxin), Akt (Akt 1/2 kinase inhibitor) or NO-synthase (L-NAME). After exposure to 5mM MβCD, pertussis toxin or Akt inhibitor could recover the β2-agonist effects on contractility, NO production and Ca2+ transient, while L-NAME only reduced NO level. An adenylyl cyclase activator (forskolin, 50nM) had no influence on the MβCD-induced changes in the β2-agonist effects. Obtained results suggest that slight cholesterol depletion upregulates Gi-protein/Akt/NO-synthase signaling that attenuates the positive inotropic response to β2-adrenergic stimulation without altering the Ca2+ transient. Whilst moderate cholesterol depletion additionally could suppress the enhancement of the Ca2+ transient amplitude caused by the β2-adrenergic agonist administration in Gi-protein/Akt-dependent but NO-independent manner.
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Affiliation(s)
- Yulia G Odnoshivkina
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - Vaycheslav I Sytchev
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - Alexey M Petrov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia.
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Zhang W, Qu X, Chen B, Snyder M, Wang M, Li B, Tang Y, Chen H, Zhu W, Zhan L, Yin N, Li D, Xie L, Liu Y, Zhang JJ, Fu XY, Rubart M, Song LS, Huang XY, Shou W. Critical Roles of STAT3 in β-Adrenergic Functions in the Heart. Circulation 2016; 133:48-61. [PMID: 26628621 PMCID: PMC4698100 DOI: 10.1161/circulationaha.115.017472] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 10/02/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND β-Adrenergic receptors (βARs) play paradoxical roles in the heart. On one hand, βARs augment cardiac performance to fulfill the physiological demands, but on the other hand, prolonged activations of βARs exert deleterious effects that result in heart failure. The signal transducer and activator of transcription 3 (STAT3) plays a dynamic role in integrating multiple cytokine signaling pathways in a number of tissues. Altered activation of STAT3 has been observed in failing hearts in both human patients and animal models. Our objective is to determine the potential regulatory roles of STAT3 in cardiac βAR-mediated signaling and function. METHODS AND RESULTS We observed that STAT3 can be directly activated in cardiomyocytes by β-adrenergic agonists. To follow up this finding, we analyzed βAR function in cardiomyocyte-restricted STAT3 knockouts and discovered that the conditional loss of STAT3 in cardiomyocytes markedly reduced the cardiac contractile response to acute βAR stimulation, and caused disengagement of calcium coupling and muscle contraction. Under chronic β-adrenergic stimulation, Stat3cKO hearts exhibited pronounced cardiomyocyte hypertrophy, cell death, and subsequent cardiac fibrosis. Biochemical and genetic data supported that Gαs and Src kinases are required for βAR-mediated activation of STAT3. Finally, we demonstrated that STAT3 transcriptionally regulates several key components of βAR pathway, including β1AR, protein kinase A, and T-type Ca(2+) channels. CONCLUSIONS Our data demonstrate for the first time that STAT3 has a fundamental role in βAR signaling and functions in the heart. STAT3 serves as a critical transcriptional regulator for βAR-mediated cardiac stress adaption, pathological remodeling, and heart failure.
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Affiliation(s)
- Wenjun Zhang
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.).
| | - Xiuxia Qu
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Biyi Chen
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Marylynn Snyder
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Meijing Wang
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Baiyan Li
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Yue Tang
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Hanying Chen
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Wuqiang Zhu
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Li Zhan
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Ni Yin
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Deqiang Li
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Li Xie
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Ying Liu
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - J Jillian Zhang
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Xin-Yuan Fu
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Michael Rubart
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Long-Sheng Song
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Xin-Yun Huang
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.)
| | - Weinian Shou
- From State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China (W. Zhang, X.Q., Y.T., W.S.); Riley Heart Research Center, Herman B. Wells Center for Pediatric Research, Department of Pediatrics, Indianapolis, IN (W. Zhang, B.L., H.C., W. Zhu, L.Z., N.Y., D.L., L.X., Y.L., M.R., W.S.); Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City (B.C., L.-S.S.); Department of Physiology and Biophysics, Cornell University Weill Medical College, New York, NY (M.S., J.J.Z., X.-Y.H.); Department of Surgery, Indiana University School of Medicine, Indianapolis (M.W.); Department of Pharmacology, Harbin Medical University, Harbin, China (B.L.); Department of Heart Surgery, Xiangya 2nd Hospital, Central South University, Changsha, China (N.Y., L.X.); and Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis (X.-Y.F.).
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Chun KS, Shim M. EP2 Induces p38 Phosphorylation via the Activation of Src in HEK 293 Cells. Biomol Ther (Seoul) 2015; 23:539-48. [PMID: 26535079 PMCID: PMC4624070 DOI: 10.4062/biomolther.2015.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 07/14/2015] [Accepted: 08/17/2015] [Indexed: 12/14/2022] Open
Abstract
Prostaglandin E2 (PGE2), a major product of cyclooxygenase, binds to four different prostaglandin E2 receptors (EP1, EP2, EP3, and EP4) which are G-protein coupled transmembrane receptors (GPCRs). Although GPCRs including EP receptors have been shown to be associated with their specific G proteins, recent evidences suggest that GPCRs can regulate MAPK signaling via non-G protein coupled pathways including Src. EP2 is differentially expressed in various tissues and the expression of EP2 is induced by extracellular stimuli. We hypothesized that an increased level of EP2 expression may affect MAPK signaling. The overexpression of EP2 in HEK 293 cells resulted in significant increase in intracellular cAMP levels response to treatment with butaprost, a specific EP2 agonist, while overexpression of EP2 alone did not increase intracellular cAMP levels. However, EP2 overexpression in the absence of PGE2 induced an increase in the level of p38 phosphorylation as well as the kinase activity of p38, suggesting that up-regulation of EP2 may promote p38 activation via non-G protein coupled pathway. Inhibition of Src completely blocked EP2-induced p38 phosphorylation and overexpression of Src increased the level of p38 phosphorylation, indicating that Src is upstream kinase for EP2-induced p38 phosphorylation. EP2 overexpression also increased the Src activity and EP2 protein was co-immunoprecipitated with Src. Furthermore, sequential co-immunoprecipitation studies showed that EP2, Src, and β-arrestin can form a complex. Our study found a novel pathway in which EP2 is associated with Src, regulating p38 pathway.
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Affiliation(s)
- Kyung-Soo Chun
- College of Pharmacy, Keimyung University, Daegu 42601, Republic of Korea
| | - Minsub Shim
- Department of Biological Sciences, University of South Carolina, Columbia, SC 29208, USA
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Bianchi E, Menicacci C, Ghelardini C. Dual effect of morphine in long-term social memory in rat. Br J Pharmacol 2015; 168:1786-93. [PMID: 23171436 DOI: 10.1111/bph.12060] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 10/02/2012] [Accepted: 10/21/2012] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Bimodal dose-response relationships have been demonstrated in animals and humans following morphine administration. We examined if systemic administration of morphine, in extremely low (μg) and high (mg, analgesic) doses, changed the learning process. EXPERIMENTAL APPROACH In the social learning test, an adult rat investigates a juvenile. The juvenile is submitted to a second encounter after a few days and investigation by the adult should be reduced. Morphine was administered before the first encounter between rats, and the critical test was performed 24, 72 or 168 h later, when animals were re-exposed to each other, in the absence of morphine. KEY RESULTS Low doses of morphine, comparable with endogenous brain concentrations, enhanced long-term memory recognition; while high doses did the reverse, indicating the adult failed to recognize the juvenile. Recognition of a familiar rat appeared to be mediated within the brain accessory olfactory bulb (AOB) by an opioid system intrinsic to the olfactory system through μ-opioid receptors (MORs). At this supraspinal site, the PLC/PKC signalling pathway was activated by extremely low morphine doses. CONCLUSIONS AND IMPLICATIONS Morphine treatment administration may either disrupt or facilitate social memory, depending on the dose, extending to memory formation the bimodal effects of morphine previously shown in pain. Social memory formation elicited by extremely low morphine doses, was mediated within the AOB by an opioid system, intrinsic to the olfactory system through MORs.
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Affiliation(s)
- Enrica Bianchi
- Department of Medical Surgical Sciences and Neuroscience, University of Siena, Siena, Italy.
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Conformational thermostabilisation of corticotropin releasing factor receptor 1. Sci Rep 2015; 5:11954. [PMID: 26159865 PMCID: PMC4498186 DOI: 10.1038/srep11954] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Accepted: 06/11/2015] [Indexed: 01/16/2023] Open
Abstract
Recent technical advances have greatly facilitated G-protein coupled receptors crystallography as evidenced by the number of successful x-ray structures that have been reported recently. These technical advances include novel detergents, specialised crystallography techniques as well as protein engineering solutions such as fusions and conformational thermostabilisation. Using conformational thermostabilisation, it is possible to generate variants of GPCRs that exhibit significantly increased stability in detergent micelles whilst preferentially occupying a single conformation. In this paper we describe for the first time the application of this technique to a member of a class B GPCR, the corticotropin releasing factor receptor 1 (CRF1R). Mutational screening in the presence of the inverse agonist, CP-376395, resulted in the identification of a construct with twelve point mutations that exhibited significantly increased thermal stability in a range of detergents. We further describe the subsequent construct engineering steps that eventually yielded a crystallisation-ready construct which recently led to the solution of the first x-ray structure of a class B receptor. Finally, we have used molecular dynamic simulation to provide structural insight into CRF1R instability as well as the stabilising effects of the mutants, which may be extended to other class B receptors considering the high degree of structural conservation.
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Weise M, Vettel C, Spiger K, Gilsbach R, Hein L, Lorenz K, Wieland T, Aktories K, Orth JHC. A systemic Pasteurella multocida toxin aggravates cardiac hypertrophy and fibrosis in mice. Cell Microbiol 2015; 17:1320-31. [PMID: 25759205 DOI: 10.1111/cmi.12436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 02/20/2015] [Accepted: 03/06/2015] [Indexed: 11/30/2022]
Abstract
Pasteurella multocida toxin (PMT) persistently activates heterotrimeric G proteins of the Gαq/11 , Gα12/13 and Gαi family without interaction with G protein-coupled receptors (GPCRs). We show that PMT acts on heart tissue in vivo and on cardiomyocytes and cardiac fibroblasts in vitro by deamidation of heterotrimeric G proteins. Increased normalized ventricle weights and fibrosis were detected after intraperitoneal administration of PMT in combination with the GPCR agonist phenylephrine. In neonatal rat cardiomyocytes, PMT stimulated the mitogen-activated protein kinase pathway, which is crucial for the development of cellular hypertrophy. The toxin induced phosphorylation of the canonical phosphorylation sites of the extracellular-regulated kinase 1/2 and, additionally, caused phosphorylation of the recently recognized autophosphorylation site, which appears to be important for the development of cellular hypertrophy. Moreover, PMT stimulated the small GTPases Rac1 and RhoA. Both switch proteins are involved in cardiomyocyte hypertrophy. In addition, PMT stimulated RhoA and Rac1 in neonatal rat cardiac fibroblasts. RhoA and Rac1 have been implicated in the regulation of connective tissue growth factor (CTGF) secretion and expression. Accordingly, we show that PMT treatment increased secretion and expression of CTGF in cardiac fibroblasts. Altogether, the data indicate that PMT is an inducer of pathological remodelling of cardiac cells and identifies the toxin as a promising tool for studying heterotrimeric G protein-dependent signalling in cardiac cells.
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Affiliation(s)
- Markus Weise
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Dept. I, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, Freiburg, 79104, Germany
| | - Christiane Vettel
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Katharina Spiger
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Ralf Gilsbach
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Dept. II, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Lutz Hein
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Dept. II, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
| | - Kristina Lorenz
- Institute of Pharmacology and Toxicology, University of Würzburg, Würzburg, Germany.,Comprehensive Heart Failure Center, University of Würzburg, Würzburg, Germany
| | - Thomas Wieland
- Institute of Experimental and Clinical Pharmacology and Toxicology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Klaus Aktories
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Dept. I, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, Freiburg, 79104, Germany.,BIOSS Centre for Biological Signalling Studies, Universität Freiburg, Freiburg, Germany
| | - Joachim H C Orth
- Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Dept. I, Albert-Ludwigs-Universität Freiburg, Albertstr. 25, Freiburg, 79104, Germany
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Abstract
One of the main strategies for cancer therapy is to use tyrosine kinase inhibitors for inhibiting tumor proliferation. Increasing evidence has demonstrated the potential risks of cardiac arrhythmias (such as prolonged QT interval) of these drugs. We report here that a widely used selective inhibitor of Src tyrosine kinases, 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2), can inhibit and prevent β-adrenergic stimulation of cardiac pacemaker activity. First, in dissected rat sinus node, PP2 inhibited and prevented the isoproterenol-induced increase of spontaneous beating rate. Second, in isolated rat sinus node myocytes, PP2 suppressed the hyperpolarization-activated "funny" current (traditionally called cardiac pacemaker current, I(f)) by negatively shifting the activation curve and decelerating activation kinetics. Third, in isolated rat sinus node myocytes, PP2 decreased the Src kinase activity, the cell surface expression, and tyrosine phosphorylation of hyperpolarization-activated, cyclic nucleotide-modulated channel 4 (HCN4) channel proteins. Finally, in human embryonic kidney 293 cells overexpressing recombinant human HCN4 channels, PP2 reversed the enhancement of HCN4 channels by isoproterenol and inhibited 573x, a cyclic adenosine momophosphate-insensitive human HCN4 mutant. These results demonstrated that inhibition of Src kinase activity in heart by PP2 decreased and prevented β-adrenergic stimulation of cardiac pacemaker activity. These effects are mediated, at least partially, by a cAMP-independent attenuation of channel activity and cell surface expression of HCN4, the main channel protein that controls the heart rate.
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Copik AJ, Baldys A, Nguyen K, Sahdeo S, Ho H, Kosaka A, Dietrich PJ, Fitch B, Raymond JR, Ford APDW, Button D, Milla ME. Isoproterenol acts as a biased agonist of the alpha-1A-adrenoceptor that selectively activates the MAPK/ERK pathway. PLoS One 2015; 10:e0115701. [PMID: 25606852 PMCID: PMC4301629 DOI: 10.1371/journal.pone.0115701] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Accepted: 11/26/2014] [Indexed: 11/24/2022] Open
Abstract
The α1A-AR is thought to couple predominantly to the Gαq/PLC pathway and lead to phosphoinositide hydrolysis and calcium mobilization, although certain agonists acting at this receptor have been reported to trigger activation of arachidonic acid formation and MAPK pathways. For several G protein-coupled receptors (GPCRs) agonists can manifest a bias for activation of particular effector signaling output, i.e. not all agonists of a given GPCR generate responses through utilization of the same signaling cascade(s). Previous work with Gαq coupling-defective variants of α1A-AR, as well as a combination of Ca2+ channel blockers, uncovered cross-talk between α1A-AR and β2-AR that leads to potentiation of a Gαq-independent signaling cascade in response to α1A-AR activation. We hypothesized that molecules exist that act as biased agonists to selectively activate this pathway. In this report, isoproterenol (Iso), typically viewed as β-AR-selective agonist, was examined with respect to activation of α1A-AR. α1A-AR selective antagonists were used to specifically block Iso evoked signaling in different cellular backgrounds and confirm its action at α1A-AR. Iso induced signaling at α1A-AR was further interrogated by probing steps along the Gαq /PLC, Gαs and MAPK/ERK pathways. In HEK-293/EBNA cells transiently transduced with α1A-AR, and CHO_α1A-AR stable cells, Iso evoked low potency ERK activity as well as Ca2+ mobilization that could be blocked by α1A-AR selective antagonists. The kinetics of Iso induced Ca2+ transients differed from typical Gαq- mediated Ca2+ mobilization, lacking both the fast IP3R mediated response and the sustained phase of Ca2+ re-entry. Moreover, no inositol phosphate (IP) accumulation could be detected in either cell line after stimulation with Iso, but activation was accompanied by receptor internalization. Data are presented that indicate that Iso represents a novel type of α1A-AR partial agonist with signaling bias toward MAPK/ERK signaling cascade that is likely independent of coupling to Gαq.
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Affiliation(s)
- Alicja. J. Copik
- Biochemical Pharmacology, Inflammation Discovery, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Aleksander Baldys
- Nephrology Division, Department of Medicine, Medical University of South Carolina, and Medical and Research Services, Ralph H Johnson Veterans Affairs Medical Center, Charleston, South Carolina 29425, United States of America
| | - Khanh Nguyen
- Discovery Technologies, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Sunil Sahdeo
- Biochemical Pharmacology, Inflammation Discovery, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Hoangdung Ho
- Discovery Technologies, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Alan Kosaka
- Discovery Technologies, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Paul J. Dietrich
- Discovery Technologies, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Bill Fitch
- Discovery Technologies, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - John R. Raymond
- Nephrology Division, Department of Medicine, Medical University of South Carolina, and Medical and Research Services, Ralph H Johnson Veterans Affairs Medical Center, Charleston, South Carolina 29425, United States of America
| | - Anthony P. D. W. Ford
- Biochemical Pharmacology, Inflammation Discovery, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Donald Button
- Biochemical Pharmacology, Inflammation Discovery, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
| | - Marcos E. Milla
- Biochemical Pharmacology, Inflammation Discovery, Roche Palo Alto LLC, 3401 Hillview Drive, Palo Alto, CA 94304, United States of America
- * E-mail:
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Sarwar M, Samuel CS, Bathgate RA, Stewart DR, Summers RJ. Serelaxin-mediated signal transduction in human vascular cells: bell-shaped concentration-response curves reflect differential coupling to G proteins. Br J Pharmacol 2014; 172:1005-19. [PMID: 25297987 DOI: 10.1111/bph.12964] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 09/16/2014] [Accepted: 09/24/2014] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND PURPOSE In a recently conducted phase III clinical trial, RELAX-AHF, serelaxin infusion over 48 h improved short- and long-term clinical outcomes in patients with acute heart failure. In this study we used human primary cells from the umbilical vasculature to better understand the signalling mechanisms activated by serelaxin. EXPERIMENTAL APPROACH We examined the acute effects of serelaxin on signal transduction mechanisms in primary human umbilical vascular cells and its chronic actions on markers of cardiovascular function and disease. KEY RESULTS The RXFP1 receptor, the cognate serelaxin receptor, was expressed at the cell surface in HUVECs and human umbilical vein smooth muscle cells (HUVSMCs), human umbilical artery smooth muscle cells (HUASMCs) and human cardiac fibroblasts (HCFs), but not human umbilical artery endothelial cells. In HUVECs and HUVSMCs, serelaxin increased cAMP, cGMP accumulation and pERK1/2, and the concentration-response curves (CRCs) were bell-shaped. Similar bell-shaped CRCs for cGMP and pERK1/2 were observed in HCFs, whereas in HUASMCs, serelaxin increased cAMP, cGMP and pERK1/2 with sigmoidal CRCs. Gαi/o and lipid raft disruption, but not Gαs inhibition, altered the serelaxin CRC for cAMP and cGMP accumulation in HUVSMC but not HUASMC. Longer term serelaxin exposure increased the expression of neuronal NOS, VEGF, ETβ receptors and MMPs (gelatinases) in RXFP1 receptor-expressing cells. CONCLUSIONS AND IMPLICATIONS Serelaxin caused acute and chronic changes in human umbilical vascular cells that were cell background dependent. Bell-shaped CRCs that were observed only in venous cells and fibroblasts involved Gαi/o located within membrane lipid rafts.
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Affiliation(s)
- M Sarwar
- Drug Discovery Biology, Monash Institute of Pharmacology, Monash University, Melbourne, Vic., Australia
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Huang J, Sun Y, Zhang JJ, Huang XY. Pivotal role of extended linker 2 in the activation of Gα by G protein-coupled receptor. J Biol Chem 2014; 290:272-83. [PMID: 25414258 DOI: 10.1074/jbc.m114.608661] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
G protein-coupled receptors (GPCRs) relay extracellular signals mainly to heterotrimeric G-proteins (Gαβγ) and they are the most successful drug targets. The mechanisms of G-protein activation by GPCRs are not well understood. Previous studies have revealed a signal relay route from a GPCR via the C-terminal α5-helix of Gα to the guanine nucleotide-binding pocket. Recent structural and biophysical studies uncover a role for the opening or rotating of the α-helical domain of Gα during the activation of Gα by a GPCR. Here we show that β-adrenergic receptors activate eight Gαs mutant proteins (from a screen of 66 Gαs mutants) that are unable to bind Gβγ subunits in cells. Five of these eight mutants are in the αF/Linker 2/β2 hinge region (extended Linker 2) that connects the Ras-like GTPase domain and the α-helical domain of Gαs. This extended Linker 2 is the target site of a natural product inhibitor of Gq. Our data show that the extended Linker 2 is critical for Gα activation by GPCRs. We propose that a GPCR via its intracellular loop 2 directly interacts with the β2/β3 loop of Gα to communicate to Linker 2, resulting in the opening and closing of the α-helical domain and the release of GDP during G-protein activation.
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Affiliation(s)
- Jianyun Huang
- From the Department of Physiology, Cornell University Weill Medical College, New York, New York 10065
| | - Yutong Sun
- From the Department of Physiology, Cornell University Weill Medical College, New York, New York 10065
| | - J Jillian Zhang
- From the Department of Physiology, Cornell University Weill Medical College, New York, New York 10065
| | - Xin-Yun Huang
- From the Department of Physiology, Cornell University Weill Medical College, New York, New York 10065
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Fang Y. Live cell optical sensing for high throughput applications. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2014; 118:153-63. [PMID: 19475370 DOI: 10.1007/10_2009_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Live cell optical sensing employs label-free optical biosensors to non-invasively measure stimulus-induced dynamic mass redistribution (DMR) in live cells within the sensing volume of the biosensor. The resultant DMR signal is an integrated cellular response, and reflects cell signaling mediated through the cellular target(s) with which the stimulus intervenes. This article describes the uses of live cell optical sensing for probing cell biology and ligand pharmacology, with an emphasis of resonant waveguide grating biosensor cellular assays for high throughput applications.
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Affiliation(s)
- Ye Fang
- Biochemical Department, Science and Technology Division, Corning Incorporated, Corning, New York, 14831, USA,
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33
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Yue L, Haroun S, Parent JL, de Brum-Fernandes AJ. Prostaglandin D(2) induces apoptosis of human osteoclasts through ERK1/2 and Akt signaling pathways. Bone 2014; 60:112-21. [PMID: 24345643 DOI: 10.1016/j.bone.2013.12.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 12/06/2013] [Accepted: 12/09/2013] [Indexed: 11/20/2022]
Abstract
In a recent study we have shown that prostaglandin D2 (PGD2) induces human osteoclast (OC) apoptosis through the activation of the chemoattractant receptor homologous molecule expressed on T-helper type 2 cell (CRTH2) receptor and the intrinsic apoptotic pathway. However, the molecular mechanisms underlying this response remain elusive. The objective of this study is to investigate the intracellular signaling pathways mediating PGD2-induced OC apoptosis. OCs were generated by in vitro differentiation of human peripheral blood mononuclear cells (PBMCs), and then treated with or without the selective inhibitors of mitogen-activated protein kinase-extracellular signal-regulated kinase (ERK) kinase, (MEK)-1/2, phosphatidylinositol3-kinase (PI3K) and NF-κB/IκB kinase-2 (IKK2) prior to the treatments of PGD2 as well as its agonists and antagonists. Fluorogenic substrate assay and immunoblotting were performed to determine the caspase-3 activity and key proteins involved in Akt, ERK1/2 and NF-κB signaling pathways. Treatments with both PGD2 and a CRTH2 agonist decreased ERK1/2 (Thr202/Tyr204) and Akt (Ser473) phosphorylation, whereas both treatments increased β-arrestin-1 phosphorylation (Ser412) in the presence of naproxen, which was used to eliminate endogenous prostaglandin production. In the absence of naproxen, treatment with a CRTH2 antagonist increased both ERK1/2 and Akt phosphorylations, and reduced the phosphorylation of β-arrestin-1. Treatment of OCs with a selective MEK-1/2 inhibitor increased caspase-3 activity and OC apoptosis induced by both PGD2 and a CRTH2 agonist. Moreover, a CRTH2 antagonist diminished the selective MEK-1/2 inhibitor-induced increase in caspase-3 activity in the presence of endogenous prostaglandins. In addition, treatment of OCs with a selective PI3K inhibitor decreased ERK1/2 (Thr202/Tyr204) phosphorylation caused by PGD2, whereas increased ERK1/2 (Thr202/Tyr204) phosphorylation by a CRTH2 antagonist was attenuated with a PI3K inhibitor treatment. The DP receptor was not implicated in any of the parameters evaluated. Treatment of OCs with PGD2 as well as its receptor agonists and antagonists did not alter the phosphorylation of RelA/p65 (Ser536). Moreover, the caspase-3 activity was not altered in OCs treated with a selective IKK2/NF-κB inhibitor. In conclusion, endogenous or exogenous PGD2 induces CRTH2-dependent apoptosis in human differentiated OCs; β-arrestin-1, ERK1/2, and Akt, but not IKK2/NF-κB are probably implicated in the signaling pathways of this receptor in the model studied.
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Affiliation(s)
- Li Yue
- Department of Pharmacology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada; Division of Rheumatology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada.
| | - Sonia Haroun
- Division of Rheumatology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada.
| | - Jean-Luc Parent
- Department of Pharmacology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada; Division of Rheumatology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada.
| | - Artur J de Brum-Fernandes
- Department of Pharmacology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada; Division of Rheumatology, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, 3001 12e Avenue Nord, Sherbrooke, Quebec J1H 5N4, Canada.
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Bruzzone A, Saulière A, Finana F, Sénard JM, Lüthy I, Galés C. Dosage-dependent regulation of cell proliferation and adhesion through dual β2-adrenergic receptor/cAMP signals. FASEB J 2013; 28:1342-54. [PMID: 24308976 DOI: 10.1096/fj.13-239285] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The role of β-adrenergic receptors (β-ARs) remains controversial in normal and tumor breast. Herein we explore the cAMP signaling involved in β-AR-dependent control of proliferation and adhesion of nontumor human breast cell line MCF-10A. Low concentrations of a β-agonist, isoproterenol (ISO), promote cell adhesion (87.5% cells remaining adherent to the plastic dishes following specific detachment vs. 35.0% in control, P<0.001), while increasing concentrations further engages an additional 36% inhibition of Erk1/2 phosphorylation (p-Erk1/2)-dependent cell proliferation (P<0.01). Isoproterenol dose response on cell adhesion was fitted to a 2-site curve (EC50(1): 16.5±11.5 fM, EC50(2): 4.08±3.09 nM), while ISO significantly inhibited p-Erk1/2 according to a 1-site model (EC50: 0.25±0.13 nM). Using β-AR-selective agonist/antagonists and cAMP analogs/inhibitors, we identified a dosage-dependent signaling in which low ISO concentrations target a β2-AR population localized in raft microdomains and stimulate a Gs/cAMP/Epac/adhesion-signaling module, while higher concentrations engage a concomitant activation of another β2-AR population outside rafts and inhibit the proliferation by a Gs/cAMP/PKA-dependent signaling module. Our data provide a new molecular basis for the dose-dependent switch of β-AR signaling. This study also sheds light on a new cAMP pathway core mechanism with a single receptor triggering dual cAMP signaling controlled by PKA or Epac but with different cellular outputs.
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Affiliation(s)
- Ariana Bruzzone
- 2Inserm U1048, Institut des Maladies Métaboliques et Cardiovasculaires, I2MC, 1, avenue Jean-Poulhès, BP84225, 31432 Toulouse Cedex 4, France.
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Ghanemi A. Targeting G protein coupled receptor-related pathways as emerging molecular therapies. Saudi Pharm J 2013; 23:115-29. [PMID: 25972730 PMCID: PMC4420995 DOI: 10.1016/j.jsps.2013.07.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 07/29/2013] [Indexed: 12/20/2022] Open
Abstract
G protein coupled receptors (GPCRs) represent the most important targets in modern pharmacology because of the different functions they mediate, especially within brain and peripheral nervous system, and also because of their functional and stereochemical properties. In this paper, we illustrate, via a variety of examples, novel advances about the GPCR-related molecules that have been shown to play diverse roles in GPCR pathways and in pathophysiological phenomena. We have exemplified how those GPCRs’ pathways are, or might constitute, potential targets for different drugs either to stimulate, modify, regulate or inhibit the cellular mechanisms that are hypothesized to govern some pathologic, physiologic, biologic and cellular or molecular aspects both in vivo and in vitro. Therefore, influencing such pathways will, undoubtedly, lead to different therapeutical applications based on the related pharmacological implications. Furthermore, such new properties can be applied in different fields. In addition to offering fruitful directions for future researches, we hope the reviewed data, together with the elements found within the cited references, will inspire clinicians and researchers devoted to the studies on GPCR’s properties.
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Affiliation(s)
- Abdelaziz Ghanemi
- Department of Pharmacology, China Pharmaceutical University, Nanjing 210009, China
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Brunskole Hummel I, Reinartz MT, Kälble S, Burhenne H, Schwede F, Buschauer A, Seifert R. Dissociations in the effects of β2-adrenergic receptor agonists on cAMP formation and superoxide production in human neutrophils: support for the concept of functional selectivity. PLoS One 2013; 8:e64556. [PMID: 23741338 PMCID: PMC3669315 DOI: 10.1371/journal.pone.0064556] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Accepted: 04/15/2013] [Indexed: 12/02/2022] Open
Abstract
In neutrophils, activation of the β2-adrenergic receptor (β2AR), a Gs-coupled receptor, inhibits inflammatory responses, which could be therapeutically exploited. The aim of this study was to evaluate the effects of various β2AR ligands on adenosine-3',5'-cyclic monophosphate (cAMP) accumulation and N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)-induced superoxide anion (O2(•-)) production in human neutrophils and to probe the concept of ligand-specific receptor conformations (also referred to as functional selectivity or biased signaling) in a native cell system. This is an important question because so far, evidence for functional selectivity has been predominantly obtained with recombinant systems, due to the inherent difficulties to genetically manipulate human native cells. cAMP concentration was determined by HPLC/tandem mass spectrometry, and O2(•-) formation was assessed by superoxide dismutase-inhibitable reduction of ferricytochrome c. β2AR agonists were generally more potent in inhibiting fMLP-induced O2(•-) production than in stimulating cAMP accumulation. (-)-Ephedrine and dichloroisoproterenol were devoid of any agonistic activity in the cAMP assay, but partially inhibited fMLP-induced O2(•-) production. Moreover, (-)-adrenaline was equi-efficacious in both assays whereas the efficacy of salbutamol was more than two-fold higher in the O2(•-) assay. Functional selectivity was visualized by deviations of ligand potencies and efficacies from linear correlations for various parameters. We obtained no evidence for involvement of protein kinase A in the inhibition of fMLP-induced O2(•-) production after β2AR-stimulation although cAMP-increasing substances inhibited O2(•-) production. Taken together, our data corroborate the concept of ligand-specific receptor conformations with unique signaling capabilities in native human cells and suggest that the β2AR inhibits O2(•-) production in a cAMP-independent manner.
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Affiliation(s)
- Irena Brunskole Hummel
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany
- Department of Pharmaceutical and Medicinal Chemistry II, University of Regensburg, Regensburg, Germany
| | | | - Solveig Kälble
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany
| | - Heike Burhenne
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany
| | | | - Armin Buschauer
- Department of Pharmaceutical and Medicinal Chemistry II, University of Regensburg, Regensburg, Germany
| | - Roland Seifert
- Institute of Pharmacology, Medical School of Hannover, Hannover, Germany
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Santulli G, Iaccarino G. Pinpointing beta adrenergic receptor in ageing pathophysiology: victim or executioner? Evidence from crime scenes. IMMUNITY & AGEING 2013; 10:10. [PMID: 23497413 PMCID: PMC3763845 DOI: 10.1186/1742-4933-10-10] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/10/2013] [Indexed: 02/07/2023]
Abstract
G protein-coupled receptors (GPCRs) play a key role in cellular communication, allowing human cells to sense external cues or to talk each other through hormones or neurotransmitters. Research in this field has been recently awarded with the Nobel Prize in chemistry to Robert J. Lefkowitz and Brian K. Kobilka, for their pioneering work on beta adrenergic receptors (βARs), a prototype GPCR. Such receptors, and β2AR in particular, which is extensively distributed throughout the body, are involved in a number of pathophysiological processes. Moreover, a large amount of studies has demonstrated their participation in ageing process. Reciprocally, age-related changes in regulation of receptor responses have been observed in numerous tissues and include modifications of βAR responses. Impaired sympathetic nervous system function has been indeed evoked as at least a partial explanation for several modifications that occur with ageing. This article represents an updated presentation of the current knowledge in the field, summarizing in a systematic way the major findings of research on ageing in several organs and tissues (crime scenes) expressing βARs: heart, vessels, skeletal muscle, respiratory system, brain, immune system, pancreatic islets, liver, kidney and bone.
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Affiliation(s)
- Gaetano Santulli
- Departments of Translational Medical Sciences and Advanced Biomedical Sciences, "Federico II" University, Naples, Italy.
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Morse M, Sun H, Tran E, Levenson R, Fang Y. Label-free integrative pharmacology on-target of opioid ligands at the opioid receptor family. BMC Pharmacol Toxicol 2013; 14:17. [PMID: 23497702 PMCID: PMC3602246 DOI: 10.1186/2050-6511-14-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Accepted: 10/31/2012] [Indexed: 01/08/2023] Open
Abstract
Background In vitro pharmacology of ligands is typically assessed using a variety of molecular assays based on predetermined molecular events in living cells. Many ligands including opioid ligands pose the ability to bind more than one receptor, and can also provide distinct operational bias to activate a specific receptor. Generating an integrative overview of the binding and functional selectivity of ligands for a receptor family is a critical but difficult step in drug discovery and development. Here we applied a newly developed label-free integrative pharmacology on-target (iPOT) approach to systematically survey the selectivity of a library of fifty-five opioid ligands against the opioid receptor family. All ligands were interrogated using dynamic mass redistribution (DMR) assays in both recombinant and native cell lines that express specific opioid receptor(s). The cells were modified with a set of probe molecules to manifest the binding and functional selectivity of ligands. DMR profiles were collected and translated to numerical coordinates that was subject to similarity analysis. A specific set of opioid ligands were then selected for quantitative pharmacology determination. Results Results showed that among fifty-five opioid ligands examined most ligands displayed agonist activity in at least one opioid receptor expressing cell line under different conditions. Further, many ligands exhibited pathway biased agonism. Conclusion We demonstrate that the iPOT effectively sorts the ligands into distinct clusters based on their binding and functional selectivity at the opioid receptor family.
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Affiliation(s)
- Megan Morse
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, PA, USA
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Crystal structure of oligomeric β1-adrenergic G protein-coupled receptors in ligand-free basal state. Nat Struct Mol Biol 2013; 20:419-25. [PMID: 23435379 PMCID: PMC3618578 DOI: 10.1038/nsmb.2504] [Citation(s) in RCA: 215] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Accepted: 01/03/2013] [Indexed: 01/23/2023]
Abstract
G protein-coupled receptors (GPCRs) mediate transmembrane signaling. Before ligand binding, GPCRs exist in a basal state. Crystal structures of several GPCRs bound with antagonists or agonists have been solved. However, the crystal structure of the ligand-free basal state of a GPCR, the starting point of GPCR activation and function, has not been determined. Here we report the X-ray crystal structure of the first ligand-free basal state of a GPCR in a lipid membrane-like environment. Oligomeric turkey β1-adrenergic receptors display two alternating dimer interfaces. One interface involves the transmembrane domain (TM) 1, TM2, the C-terminal H8, and the extracellular loop 1. The other interface engages residues from TM4, TM5, the intracellular loop 2 and the extracellular loop 2. Structural comparisons show that this ligand-free state is in an inactive conformation. This provides the structural information regarding GPCR dimerization and oligomerization.
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Magnan R, Escrieut C, Gigoux V, De K, Clerc P, Niu F, Azema J, Masri B, Cordomi A, Baltas M, Tikhonova IG, Fourmy D. Distinct CCK-2 receptor conformations associated with β-arrestin-2 recruitment or phospholipase-C activation revealed by a biased antagonist. J Am Chem Soc 2013; 135:2560-73. [PMID: 23323542 DOI: 10.1021/ja308784w] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Seven-transmembrane receptors (7TMRs), also termed G protein-coupled receptors (GPCRs), form the largest class of cell surface membrane receptors, involving several hundred members in the human genome. Nearly 30% of marketed pharmacological agents target 7TMRs. 7TMRs adopt multiple conformations upon agonist binding. Biased agonists, in contrast to non-biased agonists, are believed to stabilize conformations preferentially activating either G-protein- or β-arrestin-dependent signaling pathways. However, proof that cognate conformations of receptors display structural differences within their binding site where biased agonism initiates, are still lacking. Here, we show that a non-biased agonist, cholecystokinin (CCK) induces conformational states of the CCK2R activating Gq-protein-dependent pathway (CCK2R(G)) or recruiting β-arrestin2 (CCK2R(β)) that are pharmacologically and structurally distinct. Two structurally unrelated antagonists competitively inhibited both pathways. A third ligand (GV150013X) acted as a high affinity competitive antagonist on CCK2R(G) but was nearly inefficient as inhibitor of CCK2R(β). Several structural elements on both GV150013X and in CCK2R binding cavity, which hinder binding of GV150013X only to the CCK2R(β) were identified. At last, proximity between two conserved amino acids from transmembrane helices 3 and 7 interacting through sulfur-aromatic interaction was shown to be crucial for selective stabilization of the CCK2R(β) state. These data establish structural evidence for distinct conformations of a 7TMR associated with β-arrestin-2 recruitment or G-protein coupling and validate relevance of the design of biased ligands able to selectively target each functional conformation of 7TMRs.
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Affiliation(s)
- Rémi Magnan
- EA 4552, Université de Toulouse 3, 31432 Toulouse, France
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Giraldo J. Modeling cooperativity effects in dimeric G protein-coupled receptors. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2013; 115:349-73. [PMID: 23415098 DOI: 10.1016/b978-0-12-394587-7.00008-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
G protein-coupled receptors organize into oligomeric arrangements to exert their function. In this chapter, three models of dimeric receptors, the two-state dimer receptor model, the metabotropic glutamate receptor model, and the asymmetric/symmetric three-state dimer receptor model are revisited focusing on the cooperative effects between their binding sites and the subunits they are composed of. The mathematical analysis reveals the complexity of the intra-receptor interactions providing insights on the mechanistic aspects of receptor function.
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Affiliation(s)
- Jesús Giraldo
- Laboratory of Systems Pharmacology and Bioinformatics, Institut de Neurociències and Unitat de Bioestadística, Universitat Autònoma de Barcelona, Bellaterra, Spain
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Saulière A, Bellot M, Paris H, Denis C, Finana F, Hansen JT, Altié MF, Seguelas MH, Pathak A, Hansen JL, Sénard JM, Galés C. Deciphering biased-agonism complexity reveals a new active AT1 receptor entity. Nat Chem Biol 2012; 8:622-30. [PMID: 22634635 DOI: 10.1038/nchembio.961] [Citation(s) in RCA: 163] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Accepted: 02/28/2012] [Indexed: 02/06/2023]
Abstract
Functional selectivity of G protein-coupled receptor (GPCR) ligands toward different downstream signals has recently emerged as a general hallmark of this receptor class. However, pleiotropic and crosstalk signaling of GPCRs makes functional selectivity difficult to decode. To look from the initial active receptor point of view, we developed new, highly sensitive and direct bioluminescence resonance energy transfer-based G protein activation probes specific for all G protein isoforms, and we used them to evaluate the G protein-coupling activity of [(1)Sar(4)Ile(8)Ile]-angiotensin II (SII), previously described as an angiotensin II type 1 (AT(1)) receptor-biased agonist that is G protein independent but β-arrestin selective. By multiplexing assays sensing sequential signaling events, from receptor conformations to downstream signaling, we decoded SII as an agonist stabilizing a G protein-dependent AT(1A) receptor signaling module different from that of the physiological agonist angiotensin II, both in recombinant and primary cells. Thus, a biased agonist does not necessarily select effects from the physiological agonist but may instead stabilize and create a new distinct active pharmacological receptor entity.
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Affiliation(s)
- Aude Saulière
- Institut des Maladies Métaboliques et Cardiovasculaires, Institut National de la Santé et de la Recherche Médicale, Université Toulouse III Paul Sabatier, Toulouse, France
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Seyedabadi M, Ostad SN, Albert PR, Dehpour AR, Rahimian R, Ghazi-Khansari M, Ghahremani MH. Ser/ Thr residues at α3/β5 loop of Gαs are important in morphine-induced adenylyl cyclase sensitization but not mitogen-activated protein kinase phosphorylation. FEBS J 2012; 279:650-60. [PMID: 22177524 DOI: 10.1111/j.1742-4658.2011.08459.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The signaling switch of β2-adrenergic and μ(1) -opioid receptors from stimulatory G-protein (G(αs) ) to inhibitory G-protein (G(αi) ) (and vice versa) influences adenylyl cyclase (AC) and extracellular-regulated kinase (ERK)1/2 activation. Post-translational modifications, including dephosphorylation of G(αs) , enhance opioid receptor coupling to G(αs) . In the present study, we substituted the Ser/Thr residues of G(αs) at the α3/β5 and α4/β6 loops aiming to study the role of G(αs) lacking Ser/Thr phosphorylation with respect to AC sensitization and mitogen-activated protein kinase activation. Isoproterenol increased the cAMP concentration (EC(50) = 22.8 ± 3.4 μm) in G(αs) -transfected S49 cyc- cells but not in nontransfected cells. However, there was no significant difference between the G(αs) -wild-type (wt) and mutants. Morphine (10 μm) inhibited AC activity more efficiently in cyc- compared to G(αs) -wt introduced cells (P < 0.05); however, we did not find a notable difference between G(αs) -wt and mutants. Interestingly, G(αs) -wt transfected cells showed more sensitization with respect to AC after chronic morphine compared to nontransfected cells (101 ± 12% versus 34 ± 6%; P < 0.001); μ1-opioid receptor interacted with G(αs) , and both co-immunoprecipitated after chronic morphine exposure. Furthermore, mutation of T270A and S272A (P < 0.01), as well as T270A, S272A and S261A (P < 0.05), in α3/β5, resulted in a higher level of AC supersensitization. ERK1/2 phosphorylation was rapidly induced by isoproterenol (by 9.5 ± 2.4-fold) and morphine (22 ± 2.2-fold) in G(αs) -transfected cells; mutations of α3/β5 and α4/β6 did not affect the pattern or extent of mitogen-activated protein kinase activation. The findings of the present study show that G(αs) interacts with the μ1-opioid receptor, and the Ser/Thr mutation to Ala at the α3/β5 loop of G(αs) enhances morphine-induced AC sensitization. In addition, G(αs) was required for the rapid phosphorylation of ERK1/2 by isoproterenol but not morphine.
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Affiliation(s)
- Mohammad Seyedabadi
- Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Iran
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Kaya AI, Onaran HO, Özcan G, Ambrosio C, Costa T, Balli S, Ugur Ö. Cell contact-dependent functional selectivity of β2-adrenergic receptor ligands in stimulating cAMP accumulation and extracellular signal-regulated kinase phosphorylation. J Biol Chem 2012; 287:6362-74. [PMID: 22241475 DOI: 10.1074/jbc.m111.301820] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Activation of β(2)-adrenegic receptor (β(2)-AR) leads to an increase in intracellular cAMP and activation of ERK. These two signals are activated by the interaction of the receptor with different transducer partners. We showed that the intrinsic activities of β(2)-AR ligands for stimulating cAMP production and ERK phosphorylation responses in HEK-293 cells were not correlated. The lack of correlation resulted mainly from the discrepancy between the intrinsic activities of two groups of ligands for these two responses: The first group consisted of clenbuterol, cimaterol, procaterol, and terbutaline which acted as full agonists for cAMP production but displayed very weak effect on ERK phosphorylation. The second group comprised adrenaline and noradrenaline which displayed higher intrinsic activity for the ERK phosphorylation than for the cAMP response. Thus, both groups behaved as functionally selective ligands. The functional selectivity of the first group was observable only in adherent cells when confluence was approximately 100%. When cell-cell contact was minimized either by decreasing the density of the adherent cells or by bringing the cells into suspension, the first group of ligands gained the ability to stimulate ERK phosphorylation without a change in their effect on cAMP production. In contrast, selectivity of the second group was independent of the adherence state of the cells. Our results show that the inherent "bias" of ligands in coupling a G protein-coupled receptor to different transducers may not always be revealed as functional selectivity when there is a "cross-talk" between the signaling pathways activated by the same receptor.
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Affiliation(s)
- Ali I Kaya
- Department of Pharmacology, Ankara University, Faculty of Medicine, 06100 Ankara, Turkey
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Hazell GG, Hindmarch CC, Pope GR, Roper JA, Lightman SL, Murphy D, O’Carroll AM, Lolait SJ. G protein-coupled receptors in the hypothalamic paraventricular and supraoptic nuclei--serpentine gateways to neuroendocrine homeostasis. Front Neuroendocrinol 2012; 33:45-66. [PMID: 21802439 PMCID: PMC3336209 DOI: 10.1016/j.yfrne.2011.07.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2011] [Revised: 06/24/2011] [Accepted: 07/06/2011] [Indexed: 12/31/2022]
Abstract
G protein-coupled receptors (GPCRs) are the largest family of transmembrane receptors in the mammalian genome. They are activated by a multitude of different ligands that elicit rapid intracellular responses to regulate cell function. Unsurprisingly, a large proportion of therapeutic agents target these receptors. The paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus are important mediators in homeostatic control. Many modulators of PVN/SON activity, including neurotransmitters and hormones act via GPCRs--in fact over 100 non-chemosensory GPCRs have been detected in either the PVN or SON. This review provides a comprehensive summary of the expression of GPCRs within the PVN/SON, including data from recent transcriptomic studies that potentially expand the repertoire of GPCRs that may have functional roles in these hypothalamic nuclei. We also present some aspects of the regulation and known roles of GPCRs in PVN/SON, which are likely complemented by the activity of 'orphan' GPCRs.
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Affiliation(s)
| | | | | | | | | | | | | | - Stephen J. Lolait
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, Dorothy Hodgkin Building, School of Clinical Sciences, University of Bristol, Whitson Street, Bristol BS1 3NY, UK
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Tappe-Theodor A, Constantin CE, Tegeder I, Lechner SG, Langeslag M, Lepcynzsky P, Wirotanseng RI, Kurejova M, Agarwal N, Nagy G, Todd A, Wettschureck N, Offermanns S, Kress M, Lewin GR, Kuner R. Gαq/11 signaling tonically modulates nociceptor function and contributes to activity-dependent sensitization. Pain 2012; 153:184-196. [DOI: 10.1016/j.pain.2011.10.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 10/07/2011] [Accepted: 10/07/2011] [Indexed: 12/15/2022]
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Abstract
INTRODUCTION The need to improve drug research and development productivity continues to drive innovation in pharmacological assays. Technologies that can leverage the advantages of both molecular and phenotypic assays would hold great promise for discovery of new medicines. AREAS COVERED This article briefly reviews current label-free platforms for cell-based assays and is primarily focused on fundamental aspects of these assays using dynamic mass redistribution technology as an example. The article also presents strategies for relating label-free profiles to molecular modes of actions of drugs. EXPERT OPINION Emerging evidence suggests that label-free cellular assays are phenotypic in nature, yet permit molecular mechanistic deconvolution. Together with unique competency in throughput, sensitivity and pathway coverages, label-free cellular assays allow users to screen drugs against endogenous receptors in native cells (including disease relevant primary cells) and determine the molecular modes of action of drug molecules. However, there are challenges for label-free in both basic research and drug discovery: the deconvolution of the cellular and molecular mechanisms for the biosensor signatures of receptor-drug interactions, new methodologies for data analysis and the development of new biosensor technologies. These challenges will need to be met for the wide adoption of these assays in drug discovery.
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Affiliation(s)
- Ye Fang
- Biochemical Technologies, Science and Technology Division, Corning, Inc. , Corning, NY 14831 , USA
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Bogdelis A, Treinys R, Stankevičius E, Jurevičius J, Skeberdis VA. Src family protein tyrosine kinases modulate L-type calcium current in human atrial myocytes. Biochem Biophys Res Commun 2011; 413:116-21. [PMID: 21872572 DOI: 10.1016/j.bbrc.2011.08.066] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Accepted: 08/15/2011] [Indexed: 10/17/2022]
Abstract
In the heart, L-type voltage dependent calcium channels (L-VDCC) provide Ca(2+) for the activation of contractile apparatus. The best described pathway for L-type Ca(2+) current (I(Ca,L)) modulation is the phosphorylation of calcium channels by cAMP-dependent protein kinase A (PKA), the activity of which is predominantly regulated in opposite manner by β-adrenergic (β-ARs) and muscarinic receptors. The role of other kinases is controversial and often depends on tissues and species used in the studies. In different studies the inhibitors of tyrosine kinases have been shown either to stimulate or inhibit, or even have a biphasic effect on I(Ca,L). Moreover, there is no clear picture about the route of activation and the site of action of cardiac Src family nonreceptor tyrosine kinases (Src-nPTKs). In the present study we used PP1, a selective inhibitor of Src-nPTKs, alone and together with different activators of I(Ca,L), and demonstrated that in human atrial myocytes (HAMs): (i) Src-nPTKs are activated concomitantly with activation of cAMP-signaling cascade; (ii) Src-nPTKs attenuate PKA-dependent stimulation of I(Ca,L) by inhibiting PKA activity; (iii) Gα(s) are not involved in the direct activation of Src-nPTKs. In this way, Src-nPTKs may provide a protecting mechanism against myocardial overload under conditions of increased sympathetic activity.
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Affiliation(s)
- Andrius Bogdelis
- Lithuanian University of Health Sciences, Institute of Cardiology, 50009 Kaunas, Lithuania
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Uwada J, Anisuzzaman ASM, Nishimune A, Yoshiki H, Muramatsu I. Intracellular distribution of functional M(1) -muscarinic acetylcholine receptors in N1E-115 neuroblastoma cells. J Neurochem 2011; 118:958-67. [PMID: 21740440 DOI: 10.1111/j.1471-4159.2011.07378.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Signaling by muscarinic agonists is thought to result from the activation of cell surface acetylcholine receptors (mAChRs) that transmit extracellular signals to intracellular systems. In N1E-115 neuroblastoma cells, we detected both plasma membrane and intracellular M(1) -mAChRs using both biochemical and pharmacological methods. In intact cells, both plasma membrane and intracellular M(1) -mAChRs were detected by the hydrophobic ligand probe, 1-quinuclidinyl-[phenyl-4-(3) H]-benzilate ([(3) H]-QNB) whereas the hydrophilic probe, 1-[N-methyl-(3) H] scopolamine ([(3) H]-NMS), detected only cell surface receptors. These probes detected comparable numbers of receptors in isolated membrane preparations. Immunohistochemical studies with M(1) -mAChR antibody also detected both cell-surface and intracellular M(1) -mAChRs. Carbachol-stimulated phosphatidylinositol hydrolysis and Ca(2+) mobilization were completely inhibited by a cell-impermeable M(1) antagonist, muscarinic toxin -7 and the G(q/11) inhibitor YM-254890. However, carbachol-stimulated extracellular-regulated kinase 1/2 activation was unaffected by muscarinic toxin-7, but was blocked by the cell-permeable antagonist, pirenzepine. extracellular regulated kinase 1/2 phosphorylation was resistant to blockade of G(q/11) (YM-254890) and protein kinase C (bisindolylmaleimide I). Our data suggest that the geographically distinct M(1) -mAChRs (cell surface versus intracellular) can signal via unique signaling pathways that are differentially sensitive to cell-impermeable versus cell-permeable antagonists. Our data are of potential physiological relevance to signaling that affects both cognitive and neurodegenerative processes.
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Affiliation(s)
- Junsuke Uwada
- Division of Pharmacology, Department of Biochemistry and Bioinformative Sciences, and Organization for Life Science Advancement Programs, School of Medicine, University of Fukui, Eiheiji, Fukui, Japan
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Verzijl D, IJzerman AP. Functional selectivity of adenosine receptor ligands. Purinergic Signal 2011; 7:171-92. [PMID: 21544511 PMCID: PMC3146648 DOI: 10.1007/s11302-011-9232-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Accepted: 04/05/2011] [Indexed: 12/11/2022] Open
Abstract
Adenosine receptors are plasma membrane proteins that transduce an extracellular signal into the interior of the cell. Basically every mammalian cell expresses at least one of the four adenosine receptor subtypes. Recent insight in signal transduction cascades teaches us that the current classification of receptor ligands into agonists, antagonists, and inverse agonists relies very much on the experimental setup that was used. Upon activation of the receptors by the ubiquitous endogenous ligand adenosine they engage classical G protein-mediated pathways, resulting in production of second messengers and activation of kinases. Besides this well-described G protein-mediated signaling pathway, adenosine receptors activate scaffold proteins such as β-arrestins. Using innovative and sensitive experimental tools, it has been possible to detect ligands that preferentially stimulate the β-arrestin pathway over the G protein-mediated signal transduction route, or vice versa. This phenomenon is referred to as functional selectivity or biased signaling and implies that an antagonist for one pathway may be a full agonist for the other signaling route. Functional selectivity makes it necessary to redefine the functional properties of currently used adenosine receptor ligands and opens possibilities for new and more selective ligands. This review focuses on the current knowledge of functionally selective adenosine receptor ligands and on G protein-independent signaling of adenosine receptors through scaffold proteins.
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Affiliation(s)
- Dennis Verzijl
- Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands
| | - Ad P. IJzerman
- Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands
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