1
|
Virwani PD, Cai L, Yeung PKK, Qian G, Chen Y, Zhou L, Wong JWH, Wang Y, Ho JWK, Lau KK, Qian PY, Chung SK. Deficiency of exchange protein directly activated by cAMP (EPAC)-1 in mice augments glucose intolerance, inflammation, and gut dysbiosis associated with Western diet. MICROBIOME 2022; 10:187. [PMID: 36329549 PMCID: PMC9635209 DOI: 10.1186/s40168-022-01366-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 09/05/2022] [Indexed: 06/16/2023]
Abstract
BACKGROUND Gut microbiota (GM) dysregulation, known as dysbiosis, has been proposed as a crucial driver of obesity associated with "Western" diet (WD) consumption. Gut dysbiosis is associated with increased gut permeability, inflammation, and insulin resistance. However, host metabolic pathways implicated in the pathophysiology of gut dysbiosis are still elusive. Exchange protein directly activated by cAMP (Epac) plays a critical role in cell-cell junction formation and insulin secretion. Here, we used homozygous Epac1-knockout (Epac1-/-), Epac2-knockout (Epac2-/-), and wild-type (WT) mice to investigate the role of Epac proteins in mediating gut dysbiosis, gut permeability, and inflammation after WD feeding. RESULTS The 16S rRNA gene sequencing of fecal DNA showed that the baseline GM of Epac2-/-, but not Epac1-/-, mice was represented by a significantly higher Firmicutes to Bacteroidetes ratio and significant alterations in several taxa compared to WT mice, suggesting that Epac2-/- mice had gut dysbiosis under physiological conditions. However, an 8-week WD led to a similar gut microbiome imbalance in mice regardless of genotype. While Epac1 deficiency modestly exacerbated the WD-induced GM dysbiosis, the WD-fed Epac2-/- mice had a more significant increase in gut permeability than corresponding WT mice. After WD feeding, Epac1-/-, but not Epac2-/-, mice had significantly higher mRNA levels of tumor necrosis factor-alpha (TNF-α) and F4/80 in the epididymal white adipose tissue (EWAT), increased circulating lipocalin-2 protein and more severe glucose intolerance, suggesting greater inflammation and insulin resistance in WD-fed Epac1-/- mice than corresponding WT mice. Consistently, Epac1 protein expression was significantly reduced in the EWAT of WD-fed WT and Epac2-/- mice. CONCLUSION Despite significantly dysregulated baseline GM and a more pronounced increase in gut permeability upon WD feeding, WD-fed Epac2-/- mice did not exhibit more severe inflammation and glucose intolerance than corresponding WT mice. These findings suggest that the role of gut dysbiosis in mediating WD-associated obesity may be context-dependent. On the contrary, we demonstrate that deficiency of host signaling protein, Epac1, drives inflammation and glucose intolerance which are the hallmarks of WD-induced obesity. Video abstract.
Collapse
Affiliation(s)
- Preeti Dinesh Virwani
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
| | - Lin Cai
- Department of Ocean Science and Division of Life Science, Hong Kong University of Science and Technology, Kowloon, Hong Kong S.A.R. China
| | - Patrick Ka Kit Yeung
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
| | - Gordon Qian
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- Laboratory of Data Discovery for Health Limited (D24H), Hong Kong Science Park, Hong Kong S.A.R., China
| | - Yingxian Chen
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
| | - Lei Zhou
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
| | - Jason Wing Hon Wong
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
| | - Yu Wang
- Department of Pharmacology and Pharmacy, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong S.A.R., China
| | - Joshua Wing Kei Ho
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- Laboratory of Data Discovery for Health Limited (D24H), Hong Kong Science Park, Hong Kong S.A.R., China
| | - Kui Kai Lau
- Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong S.A.R., China
| | - Pei-Yuan Qian
- Department of Ocean Science and Division of Life Science, Hong Kong University of Science and Technology, Kowloon, Hong Kong S.A.R. China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, 511458 China
| | - Sookja Kim Chung
- Faculty of Medicine; Faculty of Innovation Engineering, Macau University of Science and Technology, Macau Special Administrative Region (S.A.R.), China
- School of Biomedical Sciences, Li Ka Shing (LKS) Faculty of Medicine, The University of Hong Kong, Hong Kong S.A.R., China
- State Key Laboratory of Pharmaceutical Biotechnology, The University of Hong Kong, Hong Kong S.A.R., China
- Dr. Neher’s Biophysics Laboratory for Innovative Drug Discovery, Macau University of Science and Technology, Macau S.A.R., China
| |
Collapse
|
2
|
Krishnan A, Bhasker AI, Singh MK, Rodriguez CI, Castro-Pérez E, Altameemi S, Lares M, Khan H, Ndiaye M, Ahmad N, Schieke SM, Setaluri V. EPAC Regulates Melanoma Growth by Stimulating mTORC1 Signaling and Loss of EPAC Signaling Dependence Correlates with Melanoma Progression. Mol Cancer Res 2022; 20:1548-1560. [PMID: 35834616 PMCID: PMC9532357 DOI: 10.1158/1541-7786.mcr-22-0026] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 06/02/2022] [Accepted: 07/08/2022] [Indexed: 11/16/2022]
Abstract
Exchange proteins directly activated by cAMP (EPAC) belong to a family of RAP guanine nucleotide exchange factors (RAPGEF). EPAC1/2 (RAPGEF3/4) activates RAP1 and the alternative cAMP signaling pathway. We previously showed that the differential growth response of primary and metastatic melanoma cells to cAMP is mediated by EPAC. However, the mechanisms responsible for this differential response to EPAC signaling are not understood. In this study, we show that pharmacologic inhibition or siRNA-mediated knockdown of EPAC selectively inhibits the growth and survival of primary melanoma cells by downregulation of cell-cycle proteins and inhibiting the cell-cycle progression independent of ERK1/2 phosphorylation. EPAC inhibition results in upregulation of AKT phosphorylation but a downregulation of mTORC1 activity and its downstream effectors. We also show that EPAC regulates both glycolysis and oxidative phosphorylation, and production of mitochondrial reactive oxygen species, preferentially in primary melanoma cells. Employing a series of genetically matched primary and lymph node metastatic (LNM) melanoma cells, and distant organ metastatic melanoma cells, we show that the LNM and metastatic melanoma cells become progressively less responsive and refractory to EPAC inhibition suggesting loss of dependency on EPAC signaling correlates with melanoma progression. Analysis of The Cancer Genome Atlas dataset showed that lower RAPGEF3, RAPGEF4 mRNA expression in primary tumor is a predictor of better disease-free survival of patients diagnosed with primary melanoma suggesting that EPAC signaling facilitates tumor progression and EPAC is a useful prognostic marker. These data highlight EPAC signaling as a potential target for prevention of melanoma progression. IMPLICATIONS This study establishes loss of dependency on EPAC-mTORC1 signaling as hallmark of primary melanoma evolution and targeting this escape mechanism is a promising strategy for metastatic melanoma.
Collapse
Affiliation(s)
- Aishwarya Krishnan
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Aishwarya I. Bhasker
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Mithalesh K. Singh
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Carlos. I. Rodriguez
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Edgardo Castro-Pérez
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Sarah Altameemi
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Marcos Lares
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Hamidullah Khan
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Mary Ndiaye
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
| | - Nihal Ahmad
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
| | - Stefan M. Schieke
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
| | - Vijayasaradhi Setaluri
- Department of Dermatology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, WI, 53705
- William S. Middleton Memorial Veterans Hospital, Madison, WI, 53705
| |
Collapse
|
3
|
Regulation of P2X1 receptors by modulators of the cAMP effectors PKA and EPAC. Proc Natl Acad Sci U S A 2021; 118:2108094118. [PMID: 34508006 DOI: 10.1073/pnas.2108094118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2021] [Indexed: 11/18/2022] Open
Abstract
P2X1 receptors are adenosine triphosphate (ATP)-gated cation channels that are functionally important for male fertility, bladder contraction, and platelet aggregation. The activity of P2X1 receptors is modulated by lipids and intracellular messengers such as cAMP, which can stimulate protein kinase A (PKA). Exchange protein activated by cAMP (EPAC) is another cAMP effector; however, its effect on P2X1 receptors has not yet been determined. Here, we demonstrate that P2X1 currents, recorded from human embryonic kidney (HEK) cells transiently transfected with P2X1 cDNA, were inhibited by the highly selective EPAC activator 007-AM. In contrast, EPAC activation enhanced P2X2 current amplitude. The PKA activator 6-MB-cAMP did not affect P2X1 currents, but inhibited P2X2 currents. The inhibitory effects of EPAC on P2X1 were prevented by triple mutation of residues 21 to 23 on the amino terminus of P2X1 subunits to the equivalent amino acids on P2X2 receptors. Double mutation of residues 21 and 22 and single mutation of residue 23 also protected P2X1 receptors from inhibition by EPAC activation. Finally, the inhibitory effects of EPAC on P2X1 were also prevented by NSC23766, an inhibitor of Rac1, a member of the Rho family of small GTPases. These data suggest that EPAC is an important regulator of P2X1 and P2X2 receptors.
Collapse
|
4
|
cAMP Compartmentalization in Cerebrovascular Endothelial Cells: New Therapeutic Opportunities in Alzheimer's Disease. Cells 2021; 10:cells10081951. [PMID: 34440720 PMCID: PMC8392343 DOI: 10.3390/cells10081951] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/19/2021] [Accepted: 07/28/2021] [Indexed: 12/20/2022] Open
Abstract
The vascular hypothesis used to explain the pathophysiology of Alzheimer’s disease (AD) suggests that a dysfunction of the cerebral microvasculature could be the beginning of alterations that ultimately leads to neuronal damage, and an abnormal increase of the blood–brain barrier (BBB) permeability plays a prominent role in this process. It is generally accepted that, in physiological conditions, cyclic AMP (cAMP) plays a key role in maintaining BBB permeability by regulating the formation of tight junctions between endothelial cells of the brain microvasculature. It is also known that intracellular cAMP signaling is highly compartmentalized into small nanodomains and localized cAMP changes are sufficient at modifying the permeability of the endothelial barrier. This spatial and temporal distribution is maintained by the enzymes involved in cAMP synthesis and degradation, by the location of its effectors, and by the existence of anchor proteins, as well as by buffers or different cytoplasm viscosities and intracellular structures limiting its diffusion. This review compiles current knowledge on the influence of cAMP compartmentalization on the endothelial barrier and, more specifically, on the BBB, laying the foundation for a new therapeutic approach in the treatment of AD.
Collapse
|
5
|
Glucagon transiently stimulates mTORC1 by activation of an EPAC/Rap1 signaling axis. Cell Signal 2021; 84:110010. [PMID: 33872697 PMCID: PMC8169602 DOI: 10.1016/j.cellsig.2021.110010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 11/22/2022]
Abstract
Activation of the protein kinase mechanistic target of rapamycin (mTOR) in both complexes 1 and 2 (mTORC1/2) in the liver is repressed during fasting and rapidly stimulated in response to a meal. The effect of feeding on hepatic mTORC1/2 is attributed to an increase in plasma levels of nutrients, such as amino acids, and insulin. By contrast, fasting is associated with elevated plasma levels of glucagon, which is conventionally viewed as having a counter-regulatory role to insulin. More recently an expanded role for glucagon action in post-prandial metabolism has been demonstrated. Herein we investigated the impact of insulin and glucagon on mTORC1/2 activation. In H4IIE and HepG2 cultures, insulin enhanced phosphorylation of the mTORC1 substrates S6K1 and 4E-BP1. Surprisingly, the effect of glucagon on mTORC1 was biphasic, wherein there was an acute increase in phosphorylation of S6K1 and 4E-BP1 over the first hour of exposure, followed by latent suppression. The transient stimulatory effect of glucagon on mTORC1 was not additive with insulin, suggesting convergent signaling. Glucagon enhanced cAMP levels and mTORC1 stimulation required activation of the glucagon receptor, PI3K/Akt, and exchange protein activated by cAMP (EPAC). EPAC acts as the guanine nucleotide exchange factor for the small GTPase Rap1. Rap1 expression enhanced S6K1 phosphorylation and glucagon addition to culture medium promoted Rap1-GTP loading. Signaling through mTORC1 acts to regulate protein synthesis and we found that glucagon promoted an EPAC-dependent increase in protein synthesis. Overall, the findings support that glucagon elicits acute activation of mTORC1/2 by an EPAC-dependent increase in Rap1-GTP.
Collapse
|
6
|
Cao X, Li Y, Shi J, Tang H. The Potentially Therapeutic Role of EPAC in Curbing the Process of Idiopathic Pulmonary Fibrosis via Differential Cellular Pathways. J Inflamm Res 2021; 14:611-619. [PMID: 33679138 PMCID: PMC7926039 DOI: 10.2147/jir.s296382] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 01/27/2021] [Indexed: 12/12/2022] Open
Abstract
Idiopathic pulmonary fibrosis (IPF) is a chronic progressive fibrosis disease caused by genetic susceptibility (causative) and other indirect risk factors such as smoking, micro-aspiration and air pollution. Repeated damage of lung epithelial cells can cause fibroblast activation and excessive collagen will lead the scar formation and severe fibrosis. It has been decades since drugs for the treatment of IPF were developed, but clinical choices were limited. Exchange Protein directly Activated by cAMP (EPAC), as a newly emerging cAMP (adenosine 3ʹ,5ʹ-cyclic monophosphate) downstream molecule, plays a vital role in the cellular pathways of IPF such as inhibiting fibroblast proliferation, stress fiber formation and epithelium cell adhesion, so it may be a novel target for drug development and treatment for curbing IPF. Here, we hypothesize that EPAC may participate in the signaling pathways related to IPF in different cell types (fibroblasts; airway smooth muscle cells; vascular endothelial cells; lung epithelial cells; macrophages; mesenchymal stem cells; T cells), thereby playing a potentially therapeutic role in resisting the process of fibrosis. We summarize the current correlation between EPAC and IPF in these different cell types, and further insights into EPAC will help to optimize the pharmacological treatment for IPF.
Collapse
Affiliation(s)
- Xinwei Cao
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Yajun Li
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| | - Jianrong Shi
- Department of Clinical Laboratory, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center For Child Health, Hangzhou, 310003, People's Republic of China
| | - Huifang Tang
- Department of Pharmacology, School of Basic Medical Sciences, Zhejiang University, Hangzhou, 310058, People's Republic of China
| |
Collapse
|
7
|
van der Horst J, Greenwood IA, Jepps TA. Cyclic AMP-Dependent Regulation of Kv7 Voltage-Gated Potassium Channels. Front Physiol 2020; 11:727. [PMID: 32695022 PMCID: PMC7338754 DOI: 10.3389/fphys.2020.00727] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/04/2020] [Indexed: 01/08/2023] Open
Abstract
Voltage-gated Kv7 potassium channels, encoded by KCNQ genes, have major physiological impacts cardiac myocytes, neurons, epithelial cells, and smooth muscle cells. Cyclic adenosine monophosphate (cAMP), a well-known intracellular secondary messenger, can activate numerous downstream effector proteins, generating downstream signaling pathways that regulate many functions in cells. A role for cAMP in ion channel regulation has been established, and recent findings show that cAMP signaling plays a role in Kv7 channel regulation. Although cAMP signaling is recognized to regulate Kv7 channels, the precise molecular mechanism behind the cAMP-dependent regulation of Kv7 channels is complex. This review will summarize recent research findings that support the mechanisms of cAMP-dependent regulation of Kv7 channels.
Collapse
Affiliation(s)
- Jennifer van der Horst
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Iain A Greenwood
- Molecular and Clinical Sciences Institute, St. George's University of London, London, United Kingdom
| | - Thomas A Jepps
- Vascular Biology Group, Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| |
Collapse
|
8
|
A Genetic Screen for Human Genes Suppressing FUS Induced Toxicity in Yeast. G3-GENES GENOMES GENETICS 2020; 10:1843-1852. [PMID: 32276960 PMCID: PMC7263679 DOI: 10.1534/g3.120.401164] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
FUS is a nucleic acid binding protein that, when mutated, cause a subset of familial amyotrophic lateral sclerosis (ALS). Expression of FUS in yeast recapitulates several pathological features of the disease-causing mutant proteins, including nuclear to cytoplasmic translocation, formation of cytoplasmic inclusions, and cytotoxicity. Genetic screens using the yeast model of FUS have identified yeast genes and their corresponding human homologs suppressing FUS induced toxicity in yeast, neurons and animal models. To expand the search for human suppressor genes of FUS induced toxicity, we carried out a genome-scale genetic screen using a newly constructed library containing 13570 human genes cloned in an inducible yeast-expression vector. Through multiple rounds of verification, we found 37 human genes that, when overexpressed, suppress FUS induced toxicity in yeast. Human genes with DNA or RNA binding functions are overrepresented among the identified suppressor genes, supporting that perturbations of RNA metabolism is a key underlying mechanism of FUS toxicity.
Collapse
|
9
|
Bai T, Yang H, Wang H, Zhi L, Liu T, Cui L, Liu W, Wang Y, Zhang M, Liu Y, Zhang Y. Inhibition of voltage-gated K+ channels mediates docosahexaenoic acid-stimulated insulin secretion in rat pancreatic β-cells. Food Funct 2020; 11:8893-8904. [DOI: 10.1039/d0fo01891k] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Kv channels play a vital role in DHA-augmented insulin secretion through GPR40/AC/cAMP/PLC signaling pathway in rat pancreatic β-cells.
Collapse
|
10
|
Abstract
Asthma is a heterogeneous inflammatory disease of the airways that is associated with airway hyperresponsiveness and airflow limitation. Although asthma was once simply categorized as atopic or nonatopic, emerging analyses over the last few decades have revealed a variety of asthma endotypes that are attributed to numerous pathophysiological mechanisms. The classification of asthma by endotype is primarily routed in different profiles of airway inflammation that contribute to bronchoconstriction. Many asthma therapeutics target G protein-coupled receptors (GPCRs), which either enhance bronchodilation or prevent bronchoconstriction. Short-acting and long-acting β 2-agonists are widely used bronchodilators that signal through the activation of the β 2-adrenergic receptor. Short-acting and long-acting antagonists of muscarinic acetylcholine receptors are used to reduce bronchoconstriction by blocking the action of acetylcholine. Leukotriene antagonists that block the signaling of cysteinyl leukotriene receptor 1 are used as an add-on therapy to reduce bronchoconstriction and inflammation induced by cysteinyl leukotrienes. A number of GPCR-targeting asthma drug candidates are also in different stages of development. Among them, antagonists of prostaglandin D2 receptor 2 have advanced into phase III clinical trials. Others, including antagonists of the adenosine A2B receptor and the histamine H4 receptor, are in early stages of clinical investigation. In the past decade, significant research advancements in pharmacology, cell biology, structural biology, and molecular physiology have greatly deepened our understanding of the therapeutic roles of GPCRs in asthma and drug action on these GPCRs. This review summarizes our current understanding of GPCR signaling and pharmacology in the context of asthma treatment. SIGNIFICANCE STATEMENT: Although current treatment methods for asthma are effective for a majority of asthma patients, there are still a large number of patients with poorly controlled asthma who may experience asthma exacerbations. This review summarizes current asthma treatment methods and our understanding of signaling and pharmacology of G protein-coupled receptors (GPCRs) in asthma therapy, and discusses controversies regarding the use of GPCR drugs and new opportunities in developing GPCR-targeting therapeutics for the treatment of asthma.
Collapse
Affiliation(s)
- Stacy Gelhaus Wendell
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (S.G.W., C.Z.); Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore (H.F.); and Department of Biological Sciences, National University of Singapore, and Center for Computational Biology, DUKE-NUS Medical School, Singapore (H.F.)
| | - Hao Fan
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (S.G.W., C.Z.); Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore (H.F.); and Department of Biological Sciences, National University of Singapore, and Center for Computational Biology, DUKE-NUS Medical School, Singapore (H.F.)
| | - Cheng Zhang
- Department of Pharmacology and Chemical Biology, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania (S.G.W., C.Z.); Bioinformatics Institute, Agency for Science, Technology, and Research, Singapore (H.F.); and Department of Biological Sciences, National University of Singapore, and Center for Computational Biology, DUKE-NUS Medical School, Singapore (H.F.)
| |
Collapse
|
11
|
Chen YF, Huang G, Wang YM, Cheng M, Zhu FF, Zhong JN, Gao YD. Exchange protein directly activated by cAMP (Epac) protects against airway inflammation and airway remodeling in asthmatic mice. Respir Res 2019; 20:285. [PMID: 31852500 PMCID: PMC6921488 DOI: 10.1186/s12931-019-1260-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 12/10/2019] [Indexed: 12/13/2022] Open
Abstract
Background β2 receptor agonists induce airway smooth muscle relaxation by increasing intracellular cAMP production. PKA is the traditional downstream signaling pathway of cAMP. Exchange protein directly activated by cAMP (Epac) was identified as another important signaling molecule of cAMP recently. The role of Epac in asthmatic airway inflammation and airway remodeling is unclear. Methods We established OVA-sensitized and -challenged acute and chronic asthma mice models to explore the expression of Epac at first. Then, airway inflammation and airway hyperresponsiveness in acute asthma mice model and airway remodeling in chronic asthma mice model were observed respectively after treatment with Epac-selective cAMP analogue 8-pCPT-2′-O-Me-cAMP (8pCPT) and Epac inhibitor ESI-09. Next, the effects of 8pCPT and ESI-09 on the proliferation and apoptosis of in vitro cultured mouse airway smooth muscle cells (ASMCs) were detected with CCK-8 assays and Annexin-V staining. Lastly, the effects of 8pCPT and ESI-09 on store-operated Ca2+ entry (SOCE) of ASMCs were examined by confocal Ca2+ fluorescence measurement. Results We found that in lung tissues of acute and chronic asthma mice models, both mRNA and protein expression of Epac1 and Epac2, two isoforms of Epac, were lower than that of control mice. In acute asthma mice model, the airway inflammatory cell infiltration, Th2 cytokines secretion and airway hyperresponsiveness were significantly attenuated by 8pCPT and aggravated by ESI-09. In chronic asthma mice model, 8pCPT decreased airway inflammatory cell infiltration and airway remodeling indexes such as collagen deposition and airway smooth muscle cell proliferation, while ESI-09 increased airway inflammation and airway remodeling. In vitro cultured mice ASMCs, 8pCPT dose-dependently inhibited, whereas ESI-09 promoted ASMCs proliferation. Interestingly, 8pCPT promoted the apoptosis of ASMCs, whereas ESI-09 had no effect on ASMCs apoptosis. Lastly, confocal Ca2+ fluorescence examination found that 8pCPT could inhibit SOCE in ASMCs at 100 μM, and ESI-09 promoted SOCE of ASMCs at 10 μM and 100 μM. In addition, the promoting effect of ESI-09 on ASMCs proliferation was inhibited by store-operated Ca2+ channel blocker, SKF-96365. Conclusions Our results suggest that Epac has a protecting effect on asthmatic airway inflammation and airway remodeling, and Epac reduces ASMCs proliferation by inhibiting SOCE in part.
Collapse
Affiliation(s)
- Yi-Fei Chen
- Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Ge Huang
- Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Yi-Min Wang
- Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Ming Cheng
- Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Fang-Fang Zhu
- Department of Intensive Care Unit, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Jin-Nan Zhong
- Department of Respiratory and Critical Care Medicine, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China
| | - Ya-Dong Gao
- Department of Allergology, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, People's Republic of China.
| |
Collapse
|
12
|
Zou T, Liu J, She L, Chen J, Zhu T, Yin J, Li X, Li X, Zhou H, Liu Z. A perspective profile of ADCY1 in cAMP signaling with drug-resistance in lung cancer. J Cancer 2019; 10:6848-6857. [PMID: 31839819 PMCID: PMC6909948 DOI: 10.7150/jca.36614] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Accepted: 08/26/2019] [Indexed: 12/11/2022] Open
Abstract
Adenylate cyclase 1 (ADCY1 or AC1) is a member of ADCY superfamily and was primarily found to be expressed in the brain. ADCY1 is responsible for catalyzing ATP to cyclic AMP (cAMP). As a secondary messenger, cAMP can regulate plenty of cellular activities. cAMP can perform its regulation in cellular transport through the binding to cAMP dependent protein kinases (PKAs), cAMP-activated guanine exchange factors (EPACs) and cyclic nucleotide-gated channels functioning in transduction of sensory signals (CNGs). Lung cancer is one of the leading factors of cancer-related death worldwide. Platinum-based chemotherapy is the first-line treatment for advanced lung cancer patients. In addition, surgical treatment, radiation treatment, and molecular targeted therapy are also therapeutic options for lung cancer patients in clinical settings. However, drug resistance and toxicity are the major obstacles that affect chemotherapy outcome and prognosis of lung cancer patients. And the therapeutic efficiency and adverse effects are varying with each individual. In recent years, investigations based on genetic sequencing have revealed the emerging role of ADCY1 mutations in affecting drug efficiency in various cancers such as lung cancer, esophageal cancer and colorectal cancer. The potential function of ADCY1 in chemotherapy resistance is of great importance to be noticed and investigated.
Collapse
Affiliation(s)
- Ting Zou
- National Institution of Drug Clinical Trial, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Junyan Liu
- Department of Orthopaedics, The First Affiliated Hospital of the University of South China, Hengyang, Hunan, P.R.China
| | - Li She
- Department of Otolaryngology Head and Neck Surgery, Xiangya Hospital, Central South University
- Otolaryngology Major Disease Research Key Laboratory of Hunan Province
| | - Juan Chen
- Changsha, Hunan, P.R.China. Department of pharmacy, Xiangya hospital, Central South University, Changsha, Hunan, P.R.China
| | - Tao Zhu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Jiye Yin
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Xi Li
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Xiangping Li
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Honghao Zhou
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| | - Zhaoqian Liu
- Department of Clinical Pharmacology, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, Hunan, P.R.China
| |
Collapse
|
13
|
Carbone E, Borges R, Eiden LE, García AG, Hernández‐Cruz A. Chromaffin Cells of the Adrenal Medulla: Physiology, Pharmacology, and Disease. Compr Physiol 2019; 9:1443-1502. [DOI: 10.1002/cphy.c190003] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
14
|
Banerjee J, Bruckbauer A, Thorpe T, Zemel MB. Biphasic Effect of Sildenafil on Energy Sensing is Mediated by Phosphodiesterases 2 and 3 in Adipocytes and Hepatocytes. Int J Mol Sci 2019; 20:ijms20122992. [PMID: 31248114 PMCID: PMC6627652 DOI: 10.3390/ijms20122992] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 06/17/2019] [Indexed: 12/14/2022] Open
Abstract
Sirt1 (Sirtuin 1), AMPK (AMP-activated protein kinase), and eNOS (endothelial nitric oxide synthase) modulate hepatic energy metabolism and inflammation and play a major role in the development of NASH. Cyclic nucleotide phosphodiesterases (PDEs) play an important role in signal transduction by modulating intracellular levels of cyclic nucleotides. We previously found the PDE5 inhibitor sildenafil to synergize with leucine and leucine-metformin combinations in preclinical studies of NASH and obesity. However, efficacy is diminished at higher sildenafil concentrations. Herein, we have successfully modeled the U-shaped sildenafil dose-response in vitro and utilized this model to assess potential mechanisms of this dose-response relationship. Adipocytes and liver cells were treated with leucine (0.5 mM) and different concentrations of sildenafil (1 nM to 100 µM). cAMP, cGMP, and P-AMPK protein expression were used to demonstrate the biphasic response for increasing concentrations of sildenafil. The reversal with higher sildenafil levels was blunted by PDE2 inhibition. These data indicate that sildenafil-mediated increases in cGMP inhibits PDE3 at lower concentrations, which increases cAMP. However, further increases in cGMP from higher sildenafil concentrations activate PDE2 and consequently decrease cAMP, which demonstrates crosstalk between cAMP and cGMP via PDE2, PDE3, and PDE5. These changes in cAMP concentration are further reflected in downstream effects, including AMPK activation.
Collapse
Affiliation(s)
- Jheelam Banerjee
- NuSirt Biopharma Inc., 11020 Solway School Rd, Knoxville, TN 37931, USA.
| | - Antje Bruckbauer
- NuSirt Biopharma Inc., 11020 Solway School Rd, Knoxville, TN 37931, USA.
| | - Teresa Thorpe
- NuSirt Biopharma Inc., 11020 Solway School Rd, Knoxville, TN 37931, USA.
| | - Michael B Zemel
- NuSirt Biopharma Inc., 11020 Solway School Rd, Knoxville, TN 37931, USA.
| |
Collapse
|
15
|
The Biosynthesis, Signaling, and Neurological Functions of Bile Acids. Biomolecules 2019; 9:biom9060232. [PMID: 31208099 PMCID: PMC6628048 DOI: 10.3390/biom9060232] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/13/2022] Open
Abstract
Bile acids (BA) are amphipathic steroid acids synthesized from cholesterol in the liver. They act as detergents to expedite the digestion and absorption of dietary lipids and lipophilic vitamins. BA are also considered to be signaling molecules, being ligands of nuclear and cell-surface receptors, including farnesoid X receptor and Takeda G-protein receptor 5. Moreover, BA also activate ion channels, including the bile acid-sensitive ion channel and epithelial Na+ channel. BA regulate glucose and lipid metabolism by activating these receptors in peripheral tissues, such as the liver and brown and white adipose tissue. Recently, 20 different BA have been identified in the central nervous system. Furthermore, BA affect the function of neurotransmitter receptors, such as the muscarinic acetylcholine receptor and γ-aminobutyric acid receptor. BA are also known to be protective against neurodegeneration. Here, we review recent findings regarding the biosynthesis, signaling, and neurological functions of BA.
Collapse
|
16
|
Striatal Cholinergic Interneurons Are a Novel Target of Corticotropin Releasing Factor. J Neurosci 2019; 39:5647-5661. [PMID: 31109960 DOI: 10.1523/jneurosci.0479-19.2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 05/03/2019] [Accepted: 05/11/2019] [Indexed: 12/21/2022] Open
Abstract
Cholinergic interneurons (CINs) are critical regulators of striatal network activity and output. Changes in CIN activity are thought to encode salient changes in the environment and stimulus-response-outcome associations. Here we report that the stress-associated neuropeptide corticotropin releasing factor (CRF) produces a profound and reliable increase in the spontaneous firing of CINs in both dorsal striatum and nucleus accumbens (NAc) through activation of CRF type 1 receptors, production of cAMP and reduction in spike accommodation in male mice. The increase of CIN firing by CRF results in the activation muscarinic acetylcholine receptors type 5, which mediate potentiation of dopamine transmission in the striatum. This study provides critical mechanistic insight into how CRF modulates striatal activity and dopamine transmission in the NAc to likely account for CRF facilitation of appetitive behaviors.SIGNIFICANCE STATEMENT Although the presence of CRF receptors in the dorsal and ventral striatum has been acknowledged, the cellular identity and the functional consequences of receptor activation is unknown. Here we report that striatal cholinergic interneurons express CRF-R1 receptors and are acutely activated by the neuropeptide CRF that is released in response to salient environmental stimuli. Cholinergic interneurons make <1% of the cells in the striatum but are critical regulators of the striatal circuitry and its output. CRF's fast and potent activation of cholinergic interneurons could have far reaching behavioral implications across motivated behaviors controlled by the striatum.
Collapse
|
17
|
Glotfelty EJ, Delgado TE, Tovar-y-Romo LB, Luo Y, Hoffer BJ, Olson L, Karlsson TE, Mattson MP, Harvey BK, Tweedie D, Li Y, Greig NH. Incretin Mimetics as Rational Candidates for the Treatment of Traumatic Brain Injury. ACS Pharmacol Transl Sci 2019; 2:66-91. [PMID: 31396586 PMCID: PMC6687335 DOI: 10.1021/acsptsci.9b00003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Indexed: 12/17/2022]
Abstract
Traumatic brain injury (TBI) is becoming an increasing public health issue. With an annually estimated 1.7 million TBIs in the United States (U.S) and nearly 70 million worldwide, the injury, isolated or compounded with others, is a major cause of short- and long-term disability and mortality. This, along with no specific treatment, has made exploration of TBI therapies a priority of the health system. Age and sex differences create a spectrum of vulnerability to TBI, with highest prevalence among younger and older populations. Increased public interest in the long-term effects and prevention of TBI have recently reached peaks, with media attention bringing heightened awareness to sport and war related head injuries. Along with short-term issues, TBI can increase the likelihood for development of long-term neurodegenerative disorders. A growing body of literature supports the use of glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic peptide (GIP), and glucagon (Gcg) receptor (R) agonists, along with unimolecular combinations of these therapies, for their potent neurotrophic/neuroprotective activities across a variety of cellular and animal models of chronic neurodegenerative diseases (Alzheimer's and Parkinson's diseases) and acute cerebrovascular disorders (stroke). Mild or moderate TBI shares many of the hallmarks of these conditions; recent work provides evidence that use of these compounds is an effective strategy for its treatment. Safety and efficacy of many incretin-based therapies (GLP-1 and GIP) have been demonstrated in humans for the treatment of type 2 diabetes mellitus (T2DM), making these compounds ideal for rapid evaluation in clinical trials of mild and moderate TBI.
Collapse
Affiliation(s)
- Elliot J. Glotfelty
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
- Department
of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Thomas E. Delgado
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Luis B. Tovar-y-Romo
- Division
of Neuroscience, Institute of Cellular Physiology, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Yu Luo
- Department
of Molecular Genetics, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Barry J. Hoffer
- Department
of Neurosurgery, Case Western Reserve University
School of Medicine, Cleveland, Ohio 44106, United States
| | - Lars Olson
- Department
of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Mark P. Mattson
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Brandon K. Harvey
- Molecular
Mechanisms of Cellular Stress and Inflammation Unit, Integrative Neuroscience
Department, National Institute on Drug Abuse,
National Institutes of Health, Baltimore, Maryland 21224, United States
| | - David Tweedie
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Yazhou Li
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| | - Nigel H. Greig
- Translational
Gerontology Branch, and Laboratory of Neurosciences, Intramural
Research Program, National Institute on
Aging, National Institutes of Health, Baltimore, Maryland 21224, United States
| |
Collapse
|
18
|
The cAMP effectors, Rap2b and EPAC, are involved in the regulation of the development of the Coxiella burnetii containing vacuole by altering the fusogenic capacity of the vacuole. PLoS One 2019; 14:e0212202. [PMID: 30763357 PMCID: PMC6375611 DOI: 10.1371/journal.pone.0212202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 01/29/2019] [Indexed: 11/23/2022] Open
Abstract
Cyclic Adenosine 3′,5′-monophosphate (cAMP) is a key second messenger known to directly regulate not only the protein kinase A (PKA) activity but also other important molecules such as the exchange protein activated by cAMP (EPAC), which is as a guanine nucleotide exchange factor (GEF) of the low molecular weight GTPase, Rap2. Coxiella burnetii is a Gram negative bacterium that survives and grows in a large Coxiella replicative vacuole (CRV), which displays lysosomal and autophagic features. In this report, we present evidence that both, EPAC and its downstream effector Rap2b, were recruited to the CRV. The transient over-expression of the Rap2b wt protein, but not its inactive mutant Rap2b ΔAAX, markedly inhibited the development of the large CRV. Additionally, Rap2b wtinhibited the fusion of early Coxiella phagosomes with the fully developed CRV, indicating that homotypic fusion events are altered in the presence of high levels of Rap2b wt. Likewise, the fusion of endosome/lysosomal compartments (heterotypic fusions) with the large CRV was also affected by the over-expression of this GTPase. Interestingly, cell overexpression of Rap2b wt markedly decreased the levels of the v-SNARE, Vamp7, suggesting that this down-regulation impairs the homotypic and heterotypic fusions events of the Coxiella vacuole.
Collapse
|
19
|
Hansen RT, Zhang HT. The Past, Present, and Future of Phosphodiesterase-4 Modulation for Age-Induced Memory Loss. ADVANCES IN NEUROBIOLOGY 2018; 17:169-199. [PMID: 28956333 DOI: 10.1007/978-3-319-58811-7_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The purpose of this chapter is to highlight the state of progress for phosphodiesterase-4 (PDE4) modulation as a potential therapeutic for psychiatric illness, and to draw attention to particular hurdles and obstacles that must be overcome in future studies to develop PDE4-mediated therapeutics. Pathological and non-pathological related memory loss will be the focus of the chapter; however, we will at times also touch upon other psychiatric illnesses like anxiety and depression. First, we will provide a brief background of PDE4, and the rationale for its extensive study in cognition. Second, we will explore fundamental differences in individual PDE4 subtypes, and then begin to address differences between pathological and non-pathological aging. Alterations of cAMP/PDE4 signaling that occur within normal vs. pathological aging, and the potential for PDE4 modulation to combat these alterations within each context will be described. Finally, we will finish the chapter with obstacles that have hindered the field, and future studies and alternative viewpoints that need to be addressed. Overall, we hope this chapter will demonstrate the incredible complexity of PDE4 signaling in the brain, and will be useful in forming a strategy to develop future PDE4-mediated therapeutics for psychiatric illnesses.
Collapse
Affiliation(s)
- Rolf T Hansen
- Departments of Behavioral Medicine & Psychiatry and Physiology & Pharmacology, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506-9137, USA
| | - Han-Ting Zhang
- Department of Behavioral Medicine and Psychiatry, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506, USA. .,Department of Physiology and Pharmacology, West Virginia University Health Sciences Center, 1 Medical Center Drive, Morgantown, WV, 26506, USA. .,Institute of Pharmacology, Taishan Medical University, Taian, 271016, China.
| |
Collapse
|
20
|
Eiden LE, Jiang SZ. What's New in Endocrinology: The Chromaffin Cell. Front Endocrinol (Lausanne) 2018; 9:711. [PMID: 30564193 PMCID: PMC6288183 DOI: 10.3389/fendo.2018.00711] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/12/2018] [Indexed: 01/08/2023] Open
Abstract
Recent advances in understanding the intracellular and intercellular features of adrenal chromatin cells as stress transducers are reviewed here, along with their implications for endocrine function in other tissues and organs participating in endocrine regulation in the mammalian organism.
Collapse
|
21
|
Abstract
History suggests β agonists, the cognate ligand of the β2 adrenoceptor, have been used as bronchodilators for around 5,000 years, and β agonists remain today the frontline treatment for asthma and chronic obstructive pulmonary disease (COPD). The β agonists used clinically today are the products of significant expenditure and over 100 year's intensive research aimed at minimizing side effects and enhancing therapeutic usefulness. The respiratory physician now has a therapeutic toolbox of long acting β agonists to prophylactically manage bronchoconstriction, and short acting β agonists to relieve acute exacerbations. Despite constituting the cornerstone of asthma and COPD therapy, these drugs are not perfect; significant safety issues have led to a black box warning advising that long acting β agonists should not be used alone in patients with asthma. In addition there are a significant proportion of patients whose asthma remains uncontrolled. In this chapter we discuss the evolution of β agonist use and how the understanding of β agonist actions on their principal target tissue, airway smooth muscle, has led to greater understanding of how these drugs can be further modified and improved in the future. Research into the genetics of the β2 adrenoceptor will also be discussed, as will the implications of individual DNA profiles on the clinical outcomes of β agonist use (pharmacogenetics). Finally we comment on what the future may hold for the use of β agonists in respiratory disease.
Collapse
Affiliation(s)
| | - Raymond B Penn
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Center for Translational Medicine, Jane and Leonard Korman Lung Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Ian P Hall
- Division of Respiratory Medicine, University of Nottingham, Nottingham, NG7 2RD, UK.
| |
Collapse
|
22
|
VanSchouwen B, Ahmed R, Milojevic J, Melacini G. Functional dynamics in cyclic nucleotide signaling and amyloid inhibition. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2017; 1865:1529-1543. [PMID: 28911813 DOI: 10.1016/j.bbapap.2017.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/29/2017] [Accepted: 09/07/2017] [Indexed: 12/28/2022]
Abstract
It is now established that understanding the molecular basis of biological function requires atomic resolution maps of both structure and dynamics. Here, we review several illustrative examples of functional dynamics selected from our work on cyclic nucleotide signaling and amyloid inhibition. Although fundamentally diverse, a central aspect common to both fields is that function can only be rationalized by considering dynamic equilibria between distinct states of the accessible free energy landscape. The dynamic exchange between ground and excited states of signaling proteins is essential to explain auto-inhibition and allosteric activation. The dynamic exchange between non-toxic monomeric species and toxic oligomers of amyloidogenic proteins provides a foundation to understand amyloid inhibition. NMR ideally probes both types of dynamic exchange at atomic resolution. Specifically, we will show how NMR was utilized to reveal the dynamical basis of cyclic nucleotide affinity, selectivity, agonism and antagonism in multiple eukaryotic cAMP and cGMP receptors. We will also illustrate how NMR revealed the mechanism of action of plasma proteins that act as extracellular chaperones and inhibit the self-association of the prototypical amyloidogenic Aβ peptide. The examples outlined in this review illustrate the widespread implications of functional dynamics and the power of NMR as an indispensable tool in molecular pharmacology and pathology.
Collapse
Affiliation(s)
- Bryan VanSchouwen
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario, Canada
| | - Rashik Ahmed
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada
| | - Julijana Milojevic
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario, Canada
| | - Giuseppe Melacini
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
| |
Collapse
|
23
|
Knott EP, Assi M, Rao SNR, Ghosh M, Pearse DD. Phosphodiesterase Inhibitors as a Therapeutic Approach to Neuroprotection and Repair. Int J Mol Sci 2017; 18:E696. [PMID: 28338622 PMCID: PMC5412282 DOI: 10.3390/ijms18040696] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 03/10/2017] [Accepted: 03/15/2017] [Indexed: 12/21/2022] Open
Abstract
A wide diversity of perturbations of the central nervous system (CNS) result in structural damage to the neuroarchitecture and cellular defects, which in turn are accompanied by neurological dysfunction and abortive endogenous neurorepair. Altering intracellular signaling pathways involved in inflammation and immune regulation, neural cell death, axon plasticity and remyelination has shown therapeutic benefit in experimental models of neurological disease and trauma. The second messengers, cyclic adenosine monophosphate (cyclic AMP) and cyclic guanosine monophosphate (cyclic GMP), are two such intracellular signaling targets, the elevation of which has produced beneficial cellular effects within a range of CNS pathologies. The only known negative regulators of cyclic nucleotides are a family of enzymes called phosphodiesterases (PDEs) that hydrolyze cyclic nucleotides into adenosine monophosphate (AMP) or guanylate monophosphate (GMP). Herein, we discuss the structure and physiological function as well as the roles PDEs play in pathological processes of the diseased or injured CNS. Further we review the approaches that have been employed therapeutically in experimental paradigms to block PDE expression or activity and in turn elevate cyclic nucleotide levels to mediate neuroprotection or neurorepair as well as discuss both the translational pathway and current limitations in moving new PDE-targeted therapies to the clinic.
Collapse
Affiliation(s)
- Eric P Knott
- Herbert Wertheim College of Medicine, Florida International University, Miami, FL 33199, USA.
| | - Mazen Assi
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Sudheendra N R Rao
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Mousumi Ghosh
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Department of Neurological Surgery, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
| | - Damien D Pearse
- The Miami Project to Cure Paralysis, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Department of Neurological Surgery, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Neuroscience Program, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- The Interdisciplinary Stem Cell Institute, The Miller School of Medicine at the University of Miami, Miami, FL 33136, USA.
- Bruce Wayne Carter Department of Veterans Affairs Medical Center, Miami, FL 33136, USA.
| |
Collapse
|
24
|
Sukhanova IF, Kozhevnikova LM, Mironova GY, Avdonin PV. The Epac protein inhibitor ESI-09 eliminates the tonic phase of aorta contraction induced by endogenic vasoconstrictors in rats. BIOL BULL+ 2017. [DOI: 10.1134/s1062359017020200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
25
|
Amunjela JN, Tucker SJ. POPDC proteins as potential novel therapeutic targets in cancer. Drug Discov Today 2016; 21:1920-1927. [PMID: 27458118 DOI: 10.1016/j.drudis.2016.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Revised: 07/10/2016] [Accepted: 07/18/2016] [Indexed: 02/08/2023]
Abstract
Popeye domain-containing (POPDC) proteins are a novel class of cAMP-binding molecules that affect cancer cell behaviour and correlate with poor clinical outcomes. They are encoded by the POPDC genes POPDC1, POPDC2, and POPDC3. The deletion of POPDC genes and the suppression of POPDC proteins correlate with enhanced cancer cell proliferation, migration, invasion, metastasis, drug resistance, and poor patient survival in various human cancers. Overexpression of POPDC proteins inhibits cancer cell migration and invasion in vitro. POPDC proteins present promising anticancer therapeutic targets and here we review their roles in promoting cancer progression and highlight their potential as anticancer therapeutic targets.
Collapse
Affiliation(s)
- Johanna N Amunjela
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK
| | - Steven J Tucker
- Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, UK.
| |
Collapse
|
26
|
Zhu Z, Di J, Lu Z, Gao K, Zheng J. Rap2B GTPase: structure, functions, and regulation. Tumour Biol 2016; 37:7085-93. [PMID: 27012552 DOI: 10.1007/s13277-016-5033-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 03/18/2016] [Indexed: 02/08/2023] Open
Abstract
Rap2B GTPase, a member of Ras-related protein superfamily, was first discovered from a platelet cDNA library in the early 1990s. Since then, it has been reported to play an important role in regulating cellular processes including cytoskeletal organization, cell growth, and proliferation. It can be stimulated and suppressed by a wide range of external and internal inducers, circulating between GTP-bound active state and GDP-bound inactive state. Increasing focus on Ras signaling pathway reveals critical effects of Rap2B on tumorigenesis. In particular, Rap2B behaves in a p53-dependent manner in regulation of apoptosis and migration. Apart from being an oncogenic activator, Rap2B has been found to participate in many other physiological events via diverse downstream effectors. In this review, we present recent studies on the structure, regulation, and multiple biological functions of Rap2B, shedding light on its potential status in treatment of cancer as well as other diseases.
Collapse
Affiliation(s)
- Zhesi Zhu
- Cancer Institute, Xuzhou Medical College, Xuzhou, 221002, Jiangsu, People's Republic of China
| | - Jiehui Di
- Cancer Institute, Xuzhou Medical College, Xuzhou, 221002, Jiangsu, People's Republic of China.,Department of Radiation Oncology and Lineberger Comprehensive Cancer Center, School of Medicine, The University of North Carolina at Chapel Hill, 101 Manning Drive, Chapel Hill, NC, 27514, USA
| | - Zheng Lu
- Cancer Institute, Xuzhou Medical College, Xuzhou, 221002, Jiangsu, People's Republic of China
| | - Keyu Gao
- Cancer Institute, Xuzhou Medical College, Xuzhou, 221002, Jiangsu, People's Republic of China
| | - Junnian Zheng
- Jiangsu Center for the Collaboration and Innovation of Cancer Biotherapy, Cancer Institute, Xuzhou Medical College, Xuzhou, 221002, Jiangsu, People's Republic of China. .,Center of Clinical Oncology, Affiliated Hospital of Xuzhou Medical College, Xuzhou, China.
| |
Collapse
|
27
|
De Rasmo D, Micelli L, Santeramo A, Signorile A, Lattanzio P, Papa S. cAMP regulates the functional activity, coupling efficiency and structural organization of mammalian FOF1 ATP synthase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2016; 1857:350-8. [PMID: 26775111 DOI: 10.1016/j.bbabio.2016.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 12/30/2015] [Accepted: 01/05/2016] [Indexed: 01/18/2023]
Abstract
The present study shows that in isolated mitochondria and myoblast cultures depletion of cAMP, induced by sAC inhibition, depresses both ATP synthesis and hydrolysis by the FOF1 ATP synthase (complex V) of the oxidative phosphorylation system (OXPHOS). These effects are accompanied by the decrease of the respiratory membrane potential, decreased level of FOF1 connecting subunits and depressed oligomerization of the complex. All these effects of sAC inhibition are prevented by the addition of the membrane-permeant 8-Br-cAMP. These results show, for the first time, that cAMP promotes ATP production by complex V and prevents, at the same time, its detour to a mitochondrial membrane leak conductance, which is involved in cell death.
Collapse
Affiliation(s)
- Domenico De Rasmo
- Institute of Biomembrane and Bioenergetics, National Research Council, Bari 70124, Italy.
| | - Loris Micelli
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari 70124, Italy
| | - Arcangela Santeramo
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari 70124, Italy
| | - Anna Signorile
- Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari 70124, Italy
| | - Paolo Lattanzio
- Institute of Biomembrane and Bioenergetics, National Research Council, Bari 70124, Italy
| | - Sergio Papa
- Institute of Biomembrane and Bioenergetics, National Research Council, Bari 70124, Italy; Department of Basic Medical Sciences, Neurosciences and Sense Organs, University of Bari "Aldo Moro", Bari 70124, Italy
| |
Collapse
|
28
|
Yang Y, Yang F, Wu X, Lv X, Li J. EPAC activation inhibits acetaldehyde-induced activation and proliferation of hepatic stellate cell via Rap1. Can J Physiol Pharmacol 2015; 94:498-507. [PMID: 26854595 DOI: 10.1139/cjpp-2015-0437] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Hepatic stellate cells (HSCs) activation represents an essential event during alcoholic liver fibrosis (ALF). Previous studies have demonstrated that the rat HSCs could be significantly activated after exposure to 200 μmol/L acetaldehyde for 48 h, and the cAMP/PKA signaling pathways were also dramatically upregulated in activated HSCs isolated from alcoholic fibrotic rat liver. Exchange protein activated by cAMP (EPAC) is a family of guanine nucleotide exchange factors (GEFs) for the small Ras-like GTPases Rap, and is being considered as a vital mediator of cAMP signaling in parallel with the principal cAMP target protein kinase A (PKA). Our data showed that both cAMP/PKA and cAMP/EPAC signaling pathways were involved in acetaldehyde-induced HSCs. Acetaldehyde could reduce the expression of EPAC1 while enhancing the expression of EPAC2. The cAMP analog Me-cAMP, which stimulates the EPAC/Rap1 pathway, could significantly decrease the proliferation and collagen synthesis of acetaldehyde-induced HSCs. Furthermore, depletion of EPAC2, but not EPAC1, prevented the activation of HSC measured as the production of α-SMA and collagen type I and III, indicating that EPAC1 appears to have protective effects on acetaldehyde-induced HSCs. Curiously, activation of PKA or EPAC perhaps has opposite effects on the synthesis of collagen and α-SMA: EPAC activation by Me-cAMP increased the levels of GTP-bound (activated) Rap1 while PKA activation by Phe-cAMP had no significant effects on such binding. These results suggested that EPAC activation could inhibit the activation and proliferation of acetaldehyde-induced HSCs via Rap1.
Collapse
Affiliation(s)
- Yan Yang
- a School of Pharmacy, Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China.,b Institute for Liver Disease of Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China
| | - Feng Yang
- a School of Pharmacy, Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China.,b Institute for Liver Disease of Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China
| | - Xiaojuan Wu
- a School of Pharmacy, Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China.,b Institute for Liver Disease of Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China
| | - Xiongwen Lv
- a School of Pharmacy, Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China.,b Institute for Liver Disease of Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China
| | - Jun Li
- a School of Pharmacy, Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China.,b Institute for Liver Disease of Anhui Medical University, Meishan Road, Hefei, Anhui Province 230032, China
| |
Collapse
|
29
|
Vitali E, Cambiaghi V, Spada A, Tresoldi A, Zerbi A, Peverelli E, Carnaghi C, Mantovani G, Lania AG. cAMP effects in neuroendocrine tumors: The role of Epac and PKA in cell proliferation and adhesion. Exp Cell Res 2015; 339:241-51. [PMID: 26589262 DOI: 10.1016/j.yexcr.2015.11.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 10/18/2015] [Accepted: 11/12/2015] [Indexed: 01/08/2023]
Abstract
cAMP effects have been initially attributed to protein kinase A (PKA) activation. Subsequently, two exchange proteins directly activated by cAMP (Epac1/2) have been identified as cAMP targets. Aim of this study was to investigate cAMP effects in pancreatic-NET (P-NET) and bronchial carcinoids and in corresponding cell lines (QGP-1 and H727) on cell proliferation and adhesion and to determine PKA and Epac role in mediating these effects. We found that cAMP increased cyclin D1 expression in P-NET and QGP-1 cells, whereas it had opposite effects on bronchial carcinoids and H727 cells and it promoted cell adhesion in QGP-1 and H727 cells. These effects are mimicked by Epac and PKA specific analogs, activating the small GTPase Rap1. In conclusion, we demonstrated that cAMP exerted divergent effects on proliferation and promoted cell adhesion of different neuroendocrine cell types, these effects being mediated by both Epac and PKA and involving the same effector GTPase Rap1.
Collapse
Affiliation(s)
- E Vitali
- Laboratory of Cellular and Molecular Endocrinology, IRCCS Clinical and Research Institute Humanitas, Rozzano, Italy
| | - V Cambiaghi
- Laboratory of Cellular and Molecular Endocrinology, IRCCS Clinical and Research Institute Humanitas, Rozzano, Italy
| | - A Spada
- Fondazione IRCCS Ospedale Maggiore Policlinico, Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, University of Milan, Italy
| | - A Tresoldi
- Laboratory of Cellular and Molecular Endocrinology, IRCCS Clinical and Research Institute Humanitas, Rozzano, Italy
| | - A Zerbi
- Pancreas Surgery Unit, IRCCS Humanitas Clinical Institute, Rozzano, Italy
| | - E Peverelli
- Fondazione IRCCS Ospedale Maggiore Policlinico, Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, University of Milan, Italy
| | - C Carnaghi
- Medical Oncology and Hematology Unit, Cancer Center, Humanitas Clinical and Research Center, Milan, Rozzano, Italy
| | - G Mantovani
- Fondazione IRCCS Ospedale Maggiore Policlinico, Endocrinology and Diabetology Unit, Department of Clinical Sciences and Community Health, University of Milan, Italy
| | - A G Lania
- Department of Biomedical Sciences, Humanitas University, Milan, Rozzano, Italy; Endocrinology Unit, Humanitas Research Hospital, Milan, Rozzano, Italy.
| |
Collapse
|
30
|
Blirando K, Blaise R, Gorodnaya N, Rouxel C, Meilhac O, Vincent P, Limon I. The stellate vascular smooth muscle cell phenotype is induced by IL-1β via the secretion of PGE2 and subsequent cAMP-dependent protein kinase A activation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:3235-47. [PMID: 26403276 DOI: 10.1016/j.bbamcr.2015.09.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/11/2015] [Accepted: 09/14/2015] [Indexed: 12/12/2022]
Abstract
Atherosclerosis development is associated with morphological changes to intimal cells, leading to a stellate cell phenotype. In this study, we aimed to determine whether and how key pro-atherogenic cytokines present in atherosclerotic plaques (IL-1β, TNFα and IFNγ) could induce this phenotype, as these molecules are known to trigger the transdifferentiation of vascular smooth muscle cells (VSMCs). We found that, IL-1β was the only major inflammatory mediator tested capable of inducing a stellate morphology in VSMCs. This finding was confirmed by staining for F-actin and vinculin at focal adhesions, as these two markers were disrupted only by IL-1β. We then investigated the possible association of this IL-1β-dependent change in morphology with an increase in intracellular cAMP concentration ([cAMP]), using the FRET-based biosensor for cAMP (T)Epac(VV). Experiments in the presence of IL-1β or medium conditioned by IL-1β-treated VSMCs and pharmacological tools demonstrated that the long-term increase in intracellular cAMP concentration was induced by the secretion of an autocrine/paracrine mediator, prostaglandin E₂(PGE₂), acting through the EP4 receptor. Finally, by knocking down the expression of the regulatory subunit PKAR1α, thereby reproducing the effects of IL-1β and PGE₂ on VSMCs, we demonstrated the contribution of PKA activity to the observed behavior of VSMCs.
Collapse
Affiliation(s)
- Karl Blirando
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France
| | - Régis Blaise
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France
| | - Natalia Gorodnaya
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France
| | - Clotilde Rouxel
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France
| | - Olivier Meilhac
- Inserm U1188 Diabète Athérothrombose Thérapies Réunion Océan Indien (DéTROI) CYROI, 2, rue Maxime Rivière, 97490 Sainte Clotilde, La Réunion, France
| | - Pierre Vincent
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France
| | - Isabelle Limon
- Sorbonne Universités, UPMC Univ Paris 06CNRS UMR 8256 B2A, IBPS, F-75005, Paris, France.
| |
Collapse
|
31
|
Sugawara K, Shibasaki T, Takahashi H, Seino S. Structure and functional roles of Epac2 (Rapgef4). Gene 2015; 575:577-83. [PMID: 26390815 DOI: 10.1016/j.gene.2015.09.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 08/13/2015] [Accepted: 09/15/2015] [Indexed: 10/24/2022]
Abstract
Epac (exchange protein activated by cyclic-AMP) 2 is a direct target of 3'-5'-cyclic adenosine monophosphate (cAMP) and is involved in cAMP-mediated signal transduction through activation of the Ras-like small GTPase Rap. Crystallographic analyses revealed that activation of Epac2 by cAMP is accompanied by dynamic structural changes. Epac2 is expressed mainly in brain, neuroendocrine and endocrine tissues, and is involved in diverse cellular functions in the tissues. In this review, we summarize the structure and function of Epac2. We also discuss the physiological and pathophysiological roles of Epac2, and the possibility of Epac2 as a therapeutic target.
Collapse
Affiliation(s)
- Kenji Sugawara
- Division of Diabetes and Endocrinology, Kobe University Graduate School of Medicine, Kobe, Japan; Division of Molecular and Metabolic Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tadao Shibasaki
- Division of Molecular and Metabolic Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Harumi Takahashi
- Division of Molecular and Metabolic Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Susumu Seino
- Division of Molecular and Metabolic Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
| |
Collapse
|
32
|
Abstract
Cyclic adenosine monophosphate (cAMP) is one of the second messengers critically involved in the molecular mechanisms underlying memory formation. In the CNS, the availability of cAMP is tightly controlled by phosphodiesterase 4 (PDE4), a family of enzymes that degrades the cyclic nucleotide to inactive AMP. Among the different PDE4 isoforms, in the last few years PDE4D has been hogging the limelight due to accumulating evidence for its crucial role in cognitive processes, which makes this enzyme a promising target for therapeutic interventions in a variety of pathological conditions characterized by memory impairment, such as Alzheimer's disease. In this article, we review the role of the cAMP signal transduction pathway in memory formation with a particular focus on the recent progress in PDE4D research.
Collapse
Affiliation(s)
- Roberta Ricciarelli
- Department of Experimental Medicine, Section of General Pathology, University of Genoa, Genoa, Italy
| | - Ernesto Fedele
- Department of Pharmacy, Section of Pharmacology and Toxicology, Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy
| |
Collapse
|
33
|
Díaz-Araya G, Vivar R, Humeres C, Boza P, Bolivar S, Muñoz C. Cardiac fibroblasts as sentinel cells in cardiac tissue: Receptors, signaling pathways and cellular functions. Pharmacol Res 2015; 101:30-40. [PMID: 26151416 DOI: 10.1016/j.phrs.2015.07.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 06/30/2015] [Accepted: 07/01/2015] [Indexed: 12/24/2022]
Abstract
Cardiac fibroblasts (CF) not only modulate extracellular matrix (ECM) proteins homeostasis, but also respond to chemical and mechanical signals. CF express a variety of receptors through which they modulate the proliferation/cell death, autophagy, adhesion, migration, turnover of ECM, expression of cytokines, chemokines, growth factors and differentiation into cardiac myofibroblasts (CMF). Differentiation of CF to CMF involves changes in the expression levels of various receptors, as well as, changes in cell phenotype and their associated functions. CF and CMF express the β2-adrenergic receptor, and its stimulation activates PKA and EPAC proteins, which differentially modulate the CF and CMF functions mentioned above. CF and CMF also express different levels of Angiotensin II receptors, in particular, AT1R activation increases collagen synthesis and cell proliferation, but its overexpression activates apoptosis. CF and CMF express different levels of B1 and B2 kinin receptors, whose stimulation by their respective agonists activates common signaling transduction pathways that decrease the synthesis and secretion of collagen through nitric oxide and prostacyclin I2 secretion. Besides these classical functions, CF can also participate in the inflammatory response of cardiac repair, through the expression of receptors commonly associated to immune cells such as Toll like receptor 4, NLRP3 and interferon receptor. The activation by their respective agonists modulates the cellular functions already described and the release of cytokines and chemokines. Thus, CF and CMF act as sentinel cells responding to a plethora of stimulus, modifying their own behavior, and that of neighboring cells.
Collapse
Affiliation(s)
- G Díaz-Araya
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile.
| | - R Vivar
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile
| | - C Humeres
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile
| | - P Boza
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile
| | - S Bolivar
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile
| | - C Muñoz
- Laboratory of Molecular Pharmacology, Chemical Pharmacological and Toxicological Department, Faculty of Chemical and Pharmaceutical Sciences, FONDAP Advanced Center for Chronic diseases ACCDiS, University of Chile, Santiago, Chile
| |
Collapse
|
34
|
Liu J, Yeung PKK, Cheng L, Lo ACY, Chung SSM, Chung SK. Epac2-deficiency leads to more severe retinal swelling, glial reactivity and oxidative stress in transient middle cerebral artery occlusion induced ischemic retinopathy. SCIENCE CHINA-LIFE SCIENCES 2015; 58:521-30. [PMID: 25985753 DOI: 10.1007/s11427-015-4860-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Accepted: 03/13/2015] [Indexed: 01/01/2023]
Abstract
Ischemia occurs in diabetic retinopathy with neuronal loss, edema, glial cell reactivity and oxidative stress. Epacs, consisting of Epac1 and Epac2, are cAMP mediators playing important roles in maintenance of endothelial barrier and neuronal functions. To investigate the roles of Epacs in the pathogenesis of ischemic retinopathy, transient middle cerebral artery occlusion (tMCAO) was performed on Epac1-deficient (Epac1 (-/-)) mice, Epac2-deficient (Epac2 (-/-)) mice, and their wild type counterparts (Epac1 (+/+) and Epac2 (+/+)). Two-hour occlusion and 22-hour reperfusion were conducted to induce ischemia/reperfusion injury to the retina. After tMCAO, the contralateral retinae displayed similar morphology between different genotypes. Neuronal loss, retinal edema and increase in immunoreactivity for aquaporin 4 (AQP4), glial fibrillary acidic protein (GFAP), peroxiredoxin 6 (Prx6) were observed in ipsilateral retinae. Epac2 (-/-) ipsilateral retinae showed more neuronal loss in retinal ganglion cell layer, increased retinal thickness and stronger immunostaining of AQP4, GFAP, and Prx6 than those of Epac2 (+/+). However, Epac1 (-/-) ipsilateral retinae displayed similar pathology as those in Epac1 (+/+) mice. Our observations suggest that Epac2-deficiency led to more severe ischemic retinopathy after retinal ischemia/reperfusion injury.
Collapse
Affiliation(s)
- Jin Liu
- Department of Anatomy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | | | | | | | | | | |
Collapse
|
35
|
Kolic J, Spigelman AF, Smith AM, Manning Fox JE, MacDonald PE. Insulin secretion induced by glucose-dependent insulinotropic polypeptide requires phosphatidylinositol 3-kinase γ in rodent and human β-cells. J Biol Chem 2014; 289:32109-32120. [PMID: 25288806 DOI: 10.1074/jbc.m114.577510] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
PI3Kγ, a G-protein-coupled type 1B phosphoinositol 3-kinase, exhibits a basal glucose-independent activity in β-cells and can be activated by the glucose-dependent insulinotropic polypeptide (GIP). We therefore investigated the role of the PI3Kγ catalytic subunit (p110γ) in insulin secretion and β-cell exocytosis stimulated by GIP. We inhibited p110γ with AS604850 (1 μmol/liter) or knocked it down using an shRNA adenovirus or siRNA duplex in mouse and human islets and β-cells. Inhibition of PI3Kγ blunted the exocytotic and insulinotropic response to GIP receptor activation, whereas responses to the glucagon-like peptide-1 or the glucagon-like peptide-1 receptor agonist exendin-4 were unchanged. Downstream, we find that GIP, much like glucose stimulation, activates the small GTPase protein Rac1 to induce actin remodeling. Inhibition of PI3Kγ blocked these effects of GIP. Although exendin-4 could also stimulate actin remodeling, this was not prevented by p110γ inhibition. Finally, forced actin depolymerization with latrunculin B restored the exocytotic and secretory responses to GIP during PI3Kγ inhibition, demonstrating that the loss of GIP-induced actin depolymerization was indeed limiting insulin exocytosis.
Collapse
Affiliation(s)
- Jelena Kolic
- Department of Pharmacology, and the Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Aliya F Spigelman
- Department of Pharmacology, and the Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Alannah M Smith
- Department of Pharmacology, and the Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Jocelyn E Manning Fox
- Department of Pharmacology, and the Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada
| | - Patrick E MacDonald
- Department of Pharmacology, and the Alberta Diabetes Institute, University of Alberta, Edmonton, Alberta T6G 2E1, Canada.
| |
Collapse
|
36
|
Borkowski K, Wrzesinski K, Rogowska-Wrzesinska A, Audouze K, Bakke J, Petersen RK, Haj FG, Madsen L, Kristiansen K. Proteomic analysis of cAMP-mediated signaling during differentiation of 3 T3-L1 preadipocytes. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:2096-107. [PMID: 25152230 DOI: 10.1016/j.bbapap.2014.07.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 07/16/2014] [Accepted: 07/21/2014] [Indexed: 01/06/2023]
Abstract
Initiation of adipocyte differentiation is promoted by the synergistic action of insulin/insulin-like growth factor, glucocorticoids, and agents activating cAMP-dependent signaling. The action of cAMP is mediated via PKA and Epac, where at least part of the PKA function relates to strong repression of Rho kinase activity, whereas Epac counteracts the reduction in insulin/insulin-like growth factor signaling associated with complete repression of Rho kinase activity. However, detailed knowledge of the Epac-dependent branch and the interplay with PKA is still limited. In the present study, we present a comprehensive evaluation of Epac-mediated processes and their interplay with PKA during the initiation of 3 T3-L1 preadipocyte differentiation using a combination of proteomics, molecular approaches, and bioinformatics. Proteomic analyses revealed 7 proteins specifically regulated in response to Epac activation, 4 in response to PKA activation, and 11 in response to the combined activation of Epac and PKA during the initial phase of differentiation. Network analyses indicated that the identified proteins are involved in pathways of importance for glucose metabolism, inositol metabolism, and calcium-dependent signaling thereby adding a novel facet to our understanding of cAMP-mediated potentiation of adipocyte differentiation.
Collapse
Affiliation(s)
- Kamil Borkowski
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, Copenhagen DK-2200, Denmark
| | - Krzysztow Wrzesinski
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M DK-5230, Denmark
| | - Adelina Rogowska-Wrzesinska
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Campusvej 55, Odense M DK-5230, Denmark
| | - Karine Audouze
- Center for Biological Sequence Analysis, Department of Systems Biology, Technical University of Denmark, Kongens Lyngby DK-2800, Denmark
| | - Jesse Bakke
- Department of Nutrition, University of California Davis, Davis, CA 95616, USA
| | - Rasmus Koefoed Petersen
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, Copenhagen DK-2200, Denmark
| | - Fawaz G Haj
- Department of Nutrition, University of California Davis, Davis, CA 95616, USA; Department of Internal Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Lise Madsen
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, Copenhagen DK-2200, Denmark; National Institute of Nutrition and Seafood Research (NIFES), Bergen N-5817, Norway.
| | - Karsten Kristiansen
- Department of Biology, University of Copenhagen, Ole Maaløes Vej 5, Copenhagen DK-2200, Denmark.
| |
Collapse
|
37
|
Vasko MR, Habashy Malty R, Guo C, Duarte DB, Zhang Y, Nicol GD. Nerve growth factor mediates a switch in intracellular signaling for PGE2-induced sensitization of sensory neurons from protein kinase A to Epac. PLoS One 2014; 9:e104529. [PMID: 25126967 PMCID: PMC4134201 DOI: 10.1371/journal.pone.0104529] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 07/13/2014] [Indexed: 12/21/2022] Open
Abstract
We examined whether nerve growth factor (NGF), an inflammatory mediator that contributes to chronic hypersensitivity, alters the intracellular signaling that mediates the sensitizing actions of PGE2 from activation of protein kinase A (PKA) to exchange proteins directly activated by cAMP (Epacs). When isolated sensory neurons are grown in the absence of added NGF, but not in cultures grown with 30 ng/ml NGF, inhibiting protein kinase A (PKA) activity blocks the ability of PGE2 to augment capsaicin-evoked release of the neuropeptide CGRP and to increase the number of action potentials (APs) evoked by a ramp of current. Growing sensory neurons in culture in the presence of increasing concentrations of NGF increases the expression of Epac2, but not Epac1. An intradermal injection of complete Freund's adjuvant into the rat hindpaw also increases the expression of Epac2, but not Epac1 in the dorsal root ganglia and spinal cord: an effect blocked by intraplantar administration of NGF antibodies. Treating cultures grown in the presence of 30 ng/ml NGF with Epac1siRNA significantly reduced the expression of Epac1, but not Epac2, and did not block the ability of PGE2 to augment capsaicin-evoked release of CGRP from sensory neurons. Exposing neuronal cultures grown in NGF to Epac2siRNAreduced the expression of Epac2, but not Epac1 and prevented the PGE2-induced augmentation of capsaicin and potassium-evoked CGRP release in sensory neurons and the PGE2-induced increase in the number of APs generated by a ramp of current. In neurons grown with no added NGF, Epac siRNAs did not attenuate PGE2-induced sensitization. These results demonstrate that NGF, through increasing Epac2 expression, alters the signaling cascade that mediates PGE2-induced sensitization of sensory neurons, thus providing a novel mechanism for maintaining PGE2-induced hypersensitivity during inflammation.
Collapse
Affiliation(s)
- Michael R. Vasko
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Anesthesia, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
| | - Ramy Habashy Malty
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Ain Shams University, Cairo, Egypt
| | - Chunlu Guo
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Djane B. Duarte
- Faculdade De Ciências da Saúde-FS, Universidade De Brasília-UNB Campus Universitário Darcy, Ribeiro-Asa Norte, Brazil
| | - Yihong Zhang
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Grant D. Nicol
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| |
Collapse
|
38
|
Joshi R, Kadeer N, Sheriff S, Friend LA, James JH, Balasubramaniam A. Phosphodiesterase (PDE) inhibitor torbafylline (HWA 448) attenuates burn-induced rat skeletal muscle proteolysis through the PDE4/cAMP/EPAC/PI3K/Akt pathway. Mol Cell Endocrinol 2014; 393:152-63. [PMID: 24973766 DOI: 10.1016/j.mce.2014.06.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 06/02/2014] [Accepted: 06/16/2014] [Indexed: 10/25/2022]
Abstract
Treatment of rats after burn-injury with the cyclic AMP phosphodiesterase (PDE) inhibitor, torbafylline (also known as HWA 448) significantly reversed changes in rat skeletal muscle proteolysis, PDE4 activity, cAMP concentrations and mRNA expression of TNFα, IL-6, ubiquitin and E3 ligases. Torbafylline also attenuated muscle proteolysis during in vitro incubation, and this effect was blocked by the inhibitor Rp-cAMPS. Moreover, torbafylline significantly increased phospho-Akt levels, and normalized downregulated phospho-FOXO1 and phospho-4E-BP1 in muscle of burn rats. Similarly, torbafylline also normalized phosphorylation levels of Akt and its downstream elements in TNFα+IFNγ treated C2C12 myotubes. Torbafylline enhanced protein levels of exchange protein directly activated by cAMP (Epac) both in skeletal muscle of burn rats and in TNFα+IFNγ treated C2C12 myotubes. Pretreatment with a specific antagonist of PI3K or Epac significantly reversed the inhibitory effects of torbafylline on TNFα+IFNγ-induced MAFbx mRNA expression and protein breakdown in C2C12 myotubes. Torbafylline inhibits burn-induced muscle proteolysis by activating multiple pathways through PDE4/cAMP/Epac/PI3K/Akt.
Collapse
Affiliation(s)
- Rashika Joshi
- Department of Surgery, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267, USA; Shriners Hospital for Children, 3229 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Nijiati Kadeer
- Shriners Hospital for Children, 3229 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Sulaiman Sheriff
- Department of Surgery, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267, USA
| | - Lou Ann Friend
- Department of Surgery, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267, USA; Shriners Hospital for Children, 3229 Burnet Avenue, Cincinnati, OH 45229, USA
| | - J Howard James
- Department of Surgery, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267, USA; Shriners Hospital for Children, 3229 Burnet Avenue, Cincinnati, OH 45229, USA
| | - Ambikaipakan Balasubramaniam
- Department of Surgery, University of Cincinnati College of Medicine, 231 Albert Sabin Way, Cincinnati, OH 45267, USA; Shriners Hospital for Children, 3229 Burnet Avenue, Cincinnati, OH 45229, USA; Cincinnati Veterans Affairs Medical Center, 3200 Vine Street, Cincinnati, OH 45220, USA.
| |
Collapse
|
39
|
Role of soluble adenylyl cyclase in cell death and growth. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2646-55. [PMID: 25010002 DOI: 10.1016/j.bbadis.2014.06.034] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/26/2014] [Accepted: 06/27/2014] [Indexed: 12/13/2022]
Abstract
cAMP signaling is an evolutionarily conserved intracellular communication system controlling numerous cellular functions. Until recently, transmembrane adenylyl cyclase (tmAC) was considered the major source for cAMP in the cell, and the role of cAMP signaling was therefore attributed exclusively to the activity of this family of enzymes. However, increasing evidence demonstrates the role of an alternative, intracellular source of cAMP produced by type 10 soluble adenylyl cyclase (sAC). In contrast to tmAC, sAC produces cAMP in various intracellular microdomains close to specific cAMP targets, e.g., in nucleus and mitochondria. Ongoing research demonstrates involvement of sAC in diverse physiological and pathological processes. The present review is focused on the role of cAMP signaling, particularly that of sAC, in cell death and growth. Although the contributions of sAC to the regulation of these cellular functions have only recently been discovered, current data suggest that sAC plays key roles in mitochondrial bioenergetics and the mitochondrial apoptosis pathway, as well as cell proliferation and development. Furthermore, recent reports suggest the importance of sAC in several pathologies associated with apoptosis as well as in oncogenesis. This article is part of a Special Issue entitled: The role of soluble adenylyl cyclase in health and disease.
Collapse
|
40
|
Clemente MI, Álvarez S, Serramía MJ, Martínez-Bonet M, Muñoz-Fernández MÁ. Prostaglandin E2 reduces the release and infectivity of new cell-free virions and cell-to-cell HIV-1 transfer. PLoS One 2014; 9:e85230. [PMID: 24586238 PMCID: PMC3934822 DOI: 10.1371/journal.pone.0085230] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 11/25/2013] [Indexed: 12/23/2022] Open
Abstract
Background The course of human immunodeficiency virus type-1 (HIV-1) infection is influenced by a complex interplay between viral and host factors. HIV infection stimulates several proinflammatory genes, such as cyclooxigense-2 (COX-2), which leads to an increase in prostaglandin (PG) levels in the plasma of HIV-1-infected patients. These genes play an indeterminate role in HIV replication and pathogenesis. The effect of prostaglandin E2 (PGE2) on HIV infection is quite controversial and even contradictory, so we sought to determine the role of PGE2 and the signal transduction pathways involved in HIV infection to elucidate possible new targets for antiretrovirals. Results Our results suggest that PGE2 post-infection treatment acts in the late stages of the viral cycle to reduce HIV replication. Interestingly, viral protein synthesis was not affected, but a loss of progeny virus production was observed. No modulation of CD4 CXCR4 and CCR5 receptor expression, cell proliferation, or activation after PGE2 treatment was detected. Moreover, PGE2 induced an increase in intracellular cAMP (cyclic AMP) levels through the EP2/EP4 receptors. PGE2 effects were mimicked by dbcAMP and by a specific Epac (exchange protein directly activated by cyclic AMP) agonist, 8-Cpt-cAMP. Treatment with PGE2 increased Rap1 activity, decreased RhoA activity and subsequently reduced the polymerization of actin by approximately 30% compared with untreated cells. In connection with this finding, polarized viral assembly platforms enriched in Gag were disrupted, altering HIV cell-to-cell transfer and the infectivity of new virions. Conclusions Our results demonstrate that PGE2, through Epac and Rap activation, alters the transport of newly synthesized HIV-1 components to the assembly site, reducing the release and infectivity of new cell-free virions and cell-to-cell HIV-1 transfer.
Collapse
Affiliation(s)
- María Isabel Clemente
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - Susana Álvarez
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - María Jesús Serramía
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - Marta Martínez-Bonet
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
| | - María Ángeles Muñoz-Fernández
- Laboratorio InmunoBiología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain
- Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
- Networking Research Center on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Zaragoza, Spain
- * E-mail:
| |
Collapse
|
41
|
Chung HJ, Mahalingam M. Angiogenesis, vasculogenic mimicry and vascular invasion in cutaneous malignant melanoma – implications for therapeutic strategies and targeted therapies. Expert Rev Anticancer Ther 2014; 14:621-39. [DOI: 10.1586/14737140.2014.883281] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
42
|
Chen H, Wild C, Zhou X, Ye N, Cheng X, Zhou J. Recent advances in the discovery of small molecules targeting exchange proteins directly activated by cAMP (EPAC). J Med Chem 2013; 57:3651-65. [PMID: 24256330 DOI: 10.1021/jm401425e] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
3',5'-Cyclic adenosine monophosphate (cAMP) is a pivotal second messenger that regulates numerous biological processes under physiological and pathological conditions, including cancer, diabetes, heart failure, inflammation, and neurological disorders. In the past, all effects of cAMP were initially believed to be mediated by protein kinase A (PKA) and cyclic nucleotide-regulated ion channels. Since the discovery of exchange proteins directly activated by cyclic adenosine 5'-monophosphate (EPACs) in 1998, accumulating evidence has demonstrated that the net cellular effects of cAMP are also regulated by EPAC. The pursuit of the biological functions of EPAC has benefited from the development and applications of a growing number of pharmacological probes targeting EPACs. In this review, we seek to provide a concise update on recent advances in the development of chemical entities including various membrane-permeable analogues of cAMP and newly discovered EPAC-specific ligands from high throughput assays and hit-to-lead optimizations.
Collapse
Affiliation(s)
- Haijun Chen
- Department of Pharmacology and Toxicology, University of Texas Medical Branch , Galveston, Texas 77555, United States
| | | | | | | | | | | |
Collapse
|
43
|
Tabibian JH, Masyuk AI, Masyuk TV, O'Hara SP, LaRusso NF. Physiology of cholangiocytes. Compr Physiol 2013; 3:541-65. [PMID: 23720296 DOI: 10.1002/cphy.c120019] [Citation(s) in RCA: 151] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Cholangiocytes are epithelial cells that line the intra- and extrahepatic ducts of the biliary tree. The main physiologic function of cholangiocytes is modification of hepatocyte-derived bile, an intricate process regulated by hormones, peptides, nucleotides, neurotransmitters, and other molecules through intracellular signaling pathways and cascades. The mechanisms and regulation of bile modification are reviewed herein.
Collapse
|
44
|
Mizuta K, Zhang Y, Xu D, Mizuta F, D'Ovidio F, Masaki E, Emala CW. The dopamine D1 receptor is expressed and facilitates relaxation in airway smooth muscle. Respir Res 2013; 14:89. [PMID: 24004608 PMCID: PMC3847358 DOI: 10.1186/1465-9921-14-89] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 08/29/2013] [Indexed: 11/17/2022] Open
Abstract
Background Dopamine signaling is mediated by Gs protein-coupled “D1-like” receptors (D1 and D5) and Gi-coupled “D2-like” receptors (D2-4). In asthmatic patients, inhaled dopamine induces bronchodilation. Although the Gi-coupled dopamine D2 receptor is expressed and sensitizes adenylyl cyclase activity in airway smooth muscle (ASM) cells, the Gs-coupled dopamine D1-like receptor subtypes have never been identified on these cells. Activation of Gs-coupled receptors stimulates cyclic AMP (cAMP) production through the stimulation of adenylyl cyclase, which promotes ASM relaxation. We questioned whether the dopamine D1-like receptor is expressed on ASM, and modulates its function through Gs-coupling. Methods The mRNA and protein expression of dopamine D1-like receptor subtypes in both native human and guinea pig ASM tissue and cultured human ASM (HASM) cells was measured. To characterize the stimulation of cAMP through the dopamine D1 receptor, HASM cells were treated with dopamine or the dopamine D1-like receptor agonists (A68930 or SKF38393) before cAMP measurements. To evaluate whether the activation of dopamine D1 receptor induces ASM relaxation, guinea pig tracheal rings suspended under isometric tension in organ baths were treated with cumulatively increasing concentrations of dopamine or A68930, following an acetylcholine-induced contraction with or without the cAMP-dependent protein kinase (PKA) inhibitor Rp-cAMPS, the large-conductance calcium-activated potassium (BKCa) channel blocker iberiotoxin, or the exchange proteins directly activated by cAMP (Epac) antagonist NSC45576. Results Messenger RNA encoding the dopamine D1 and D5 receptors were detected in native human ASM tissue and cultured HASM cells. Immunoblots confirmed the protein expression of the dopamine D1 receptor in both native human and guinea pig ASM tissue and cultured HASM cells. The dopamine D1 receptor was also immunohistochemically localized to both human and guinea pig ASM. The dopamine D1-like receptor agonists stimulated cAMP production in HASM cells, which was reversed by the selective dopamine D1-like receptor antagonists SCH23390 or SCH39166. A68930 relaxed acetylcholine-contracted guinea pig tracheal rings, which was attenuated by Rp-cAMPS but not by iberiotoxin or NSC45576. Conclusions These results demonstrate that the dopamine D1 receptors are expressed on ASM and regulate smooth muscle force via cAMP activation of PKA, and offer a novel target for therapeutic relaxation of ASM.
Collapse
Affiliation(s)
- Kentaro Mizuta
- Departments of Anesthesiology, College of Physicians and Surgeons of Columbia University, 630W 168th St, P&S Box 46, New York, NY 10032, USA.
| | | | | | | | | | | | | |
Collapse
|
45
|
Monteiro AC, Sumagin R, Rankin CR, Leoni G, Mina MJ, Reiter DM, Stehle T, Dermody TS, Schaefer SA, Hall RA, Nusrat A, Parkos CA. JAM-A associates with ZO-2, afadin, and PDZ-GEF1 to activate Rap2c and regulate epithelial barrier function. Mol Biol Cell 2013; 24:2849-60. [PMID: 23885123 PMCID: PMC3771947 DOI: 10.1091/mbc.e13-06-0298] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Intestinal barrier function is regulated by epithelial tight junctions, structures that control paracellular permeability. JAM-A regulates epithelial permeability through association with ZO-2, afadin, and PDZ-GEF1 to activate Rap2c and control contraction of the apical cytoskeleton. Intestinal barrier function is regulated by epithelial tight junctions (TJs), structures that control paracellular permeability. Junctional adhesion molecule-A (JAM-A) is a TJ-associated protein that regulates barrier; however, mechanisms linking JAM-A to epithelial permeability are poorly understood. Here we report that JAM-A associates directly with ZO-2 and indirectly with afadin, and this complex, along with PDZ-GEF1, activates the small GTPase Rap2c. Supporting a functional link, small interfering RNA–mediated down-regulation of the foregoing regulatory proteins results in enhanced permeability similar to that observed after JAM-A loss. JAM-A–deficient mice and cultured epithelial cells demonstrate enhanced paracellular permeability to large molecules, revealing a potential role of JAM-A in controlling perijunctional actin cytoskeleton in addition to its previously reported role in regulating claudin proteins and small-molecule permeability. Further experiments suggest that JAM-A does not regulate actin turnover but modulates activity of RhoA and phosphorylation of nonmuscle myosin, both implicated in actomyosin contraction. These results suggest that JAM-A regulates epithelial permeability via association with ZO-2, afadin, and PDZ-GEF1 to activate Rap2c and control contraction of the apical cytoskeleton.
Collapse
Affiliation(s)
- Ana C Monteiro
- Department of Pathology, Emory University School of Medicine, Atlanta, GA 30306 Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30306 Emory Rollins School of Public Health, Atlanta, GA 30306 Interfaculty Institute of Biochemistry, University of Tübingen, D-72076 Tübingen, Germany Department of Pediatrics and Pathology, Vanderbilt University School of Medicine, Nashville, TN 37230 Departments of Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37230 Elizabeth B. Lamb Center for Pediatric Research, Vanderbilt University School of Medicine, Nashville, TN 37230
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Abstract
Phosphorylation of mitochondrial proteins has emerged as a major regulatory mechanism for metabolic adaptation. cAMP signaling and PKA phosphorylation of mitochondrial proteins have just started to be investigated, and the presence of cAMP-generating enzymes and PKA inside mitochondria is still controversial. Here, we discuss the role of cAMP in regulating mitochondrial bioenergetics through protein phosphorylation and the evidence for soluble adenylyl cyclase as the source of cAMP inside mitochondria.
Collapse
Affiliation(s)
- Federica Valsecchi
- Department of Neurology and Neuroscience, Weill Medical College of Cornell University, New York, USA
| | | | | | | | | |
Collapse
|
47
|
Neukamm SS, Ott J, Dammeier S, Lehmann R, Häring HU, Schleicher E, Weigert C. Phosphorylation of serine 1137/1138 of mouse insulin receptor substrate (IRS) 2 regulates cAMP-dependent binding to 14-3-3 proteins and IRS2 protein degradation. J Biol Chem 2013; 288:16403-16415. [PMID: 23615913 DOI: 10.1074/jbc.m113.474593] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Insulin receptor substrate (IRS) 2 as intermediate docking platform transduces the insulin/IGF-1 (insulin like growth factor 1) signal to intracellular effector molecules that regulate glucose homeostasis, β-cell growth, and survival. Previously, IRS2 has been identified as a 14-3-3 interaction protein. 14-3-3 proteins can bind their target proteins via phosphorylated serine/threonine residues located within distinct motifs. In this study the binding of 14-3-3 to IRS2 upon stimulation with forskolin or the cAMP analog 8-(4-chlorophenylthio)-cAMP was demonstrated in HEK293 cells. Binding was reduced with PKA inhibitors H89 or Rp-8-Br-cAMPS. Phosphorylation of IRS2 on PKA consensus motifs was induced by forskolin and the PKA activator N(6)-Phe-cAMP and prevented by both PKA inhibitors. The amino acid region after position 952 on IRS2 was identified as the 14-3-3 binding region by GST-14-3-3 pulldown assays. Mass spectrometric analysis revealed serine 1137 and serine 1138 as cAMP-dependent, potential PKA phosphorylation sites. Mutation of serine 1137/1138 to alanine strongly reduced the cAMP-dependent 14-3-3 binding. Application of cycloheximide revealed that forskolin enhanced IRS2 protein stability in HEK293 cells stably expressing IRS2 as well as in primary hepatocytes. Stimulation with forskolin did not increase protein stability either in the presence of a 14-3-3 antagonist or in the double 1137/1138 alanine mutant. Thus the reduced IRS2 protein degradation was dependent on the interaction with 14-3-3 proteins and the presence of serine 1137/1138. We present serine 1137/1138 as novel cAMP-dependent phosphorylation sites on IRS2 and show their importance in 14-3-3 binding and IRS2 protein stability.
Collapse
Affiliation(s)
- Sabine S Neukamm
- Division of Clinical Chemistry and Pathobiochemistry, Tuebingen 72076, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (Paul Langerhans Institute Tuebingen), Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen 72076, Germany
| | - Jennifer Ott
- Medical Proteome Center, Institute for Ophtalmic Research, University Hospital Tuebingen, Tuebingen 72076, Germany
| | - Sascha Dammeier
- Medical Proteome Center, Institute for Ophtalmic Research, University Hospital Tuebingen, Tuebingen 72076, Germany
| | - Rainer Lehmann
- Division of Clinical Chemistry and Pathobiochemistry, Tuebingen 72076, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (Paul Langerhans Institute Tuebingen), Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen 72076, Germany
| | - Hans-Ulrich Häring
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (Paul Langerhans Institute Tuebingen), Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen 72076, Germany; Division of Endocrinology, Diabetology, Vascular Medicine, Nephrology and Clinical Chemistry, Department of Internal Medicine IV, Tuebingen 72076, Germany
| | - Erwin Schleicher
- Division of Clinical Chemistry and Pathobiochemistry, Tuebingen 72076, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (Paul Langerhans Institute Tuebingen), Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen 72076, Germany
| | - Cora Weigert
- Division of Clinical Chemistry and Pathobiochemistry, Tuebingen 72076, Germany; Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tuebingen (Paul Langerhans Institute Tuebingen), Tuebingen, Germany; German Center for Diabetes Research (DZD), Tuebingen 72076, Germany.
| |
Collapse
|
48
|
Oldenburger A, Maarsingh H, Schmidt M. Multiple facets of cAMP signalling and physiological impact: cAMP compartmentalization in the lung. Pharmaceuticals (Basel) 2012; 5:1291-331. [PMID: 24281338 PMCID: PMC3816672 DOI: 10.3390/ph5121291] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Revised: 11/15/2012] [Accepted: 11/20/2012] [Indexed: 12/20/2022] Open
Abstract
Therapies involving elevation of the endogenous suppressor cyclic AMP (cAMP) are currently used in the treatment of several chronic inflammatory disorders, including chronic obstructive pulmonary disease (COPD). Characteristics of COPD are airway obstruction, airway inflammation and airway remodelling, processes encompassed by increased airway smooth muscle mass, epithelial changes, goblet cell and submucosal gland hyperplasia. In addition to inflammatory cells, airway smooth muscle cells and (myo)fibroblasts, epithelial cells underpin a variety of key responses in the airways such as inflammatory cytokine release, airway remodelling, mucus hypersecretion and airway barrier function. Cigarette smoke, being next to environmental pollution the main cause of COPD, is believed to cause epithelial hyperpermeability by disrupting the barrier function. Here we will focus on the most recent progress on compartmentalized signalling by cAMP. In addition to G protein-coupled receptors, adenylyl cyclases, cAMP-specific phospho-diesterases (PDEs) maintain compartmentalized cAMP signalling. Intriguingly, spatially discrete cAMP-sensing signalling complexes seem also to involve distinct members of the A-kinase anchoring (AKAP) superfamily and IQ motif containing GTPase activating protein (IQGAPs). In this review, we will highlight the interaction between cAMP and the epithelial barrier to retain proper lung function and to alleviate COPD symptoms and focus on the possible molecular mechanisms involved in this process. Future studies should include the development of cAMP-sensing multiprotein complex specific disruptors and/or stabilizers to orchestrate cellular functions. Compartmentalized cAMP signalling regulates important cellular processes in the lung and may serve as a therapeutic target.
Collapse
Affiliation(s)
- Anouk Oldenburger
- Department of Molecular Pharmacology, Groningen Research Institute for Pharmacy, University of Groningen, 9713 AV, Groningen, The Netherlands.
| | | | | |
Collapse
|
49
|
Monteiro AC, Parkos CA. Intracellular mediators of JAM-A-dependent epithelial barrier function. Ann N Y Acad Sci 2012; 1257:115-24. [PMID: 22671597 DOI: 10.1111/j.1749-6632.2012.06521.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Junctional adhesion molecule-A (JAM-A) is a critical signaling component of the apical junctional complex, a structure composed of several transmembrane and scaffold molecules that controls the passage of nutrients and solutes across epithelial surfaces. Observations from JAM-A-deficient epithelial cells and JAM-A knockout animals indicate that JAM-A is an important regulator of epithelial paracellular permeability; however, the mechanism(s) linking JAM-A to barrier function are not understood. This review highlights recent findings relevant to JAM-A-mediated regulation of epithelial permeability, focusing on the role of upstream and downstream signaling candidates. We draw on what is known about proteins reported to associate with JAM-A in other pathways and on known modulators of barrier function to propose candidate effectors that may mediate JAM-A regulation of epithelial paracellular permeability. Further investigation of pathways highlighted in this review may provide ideas for novel therapeutics that target debilitating conditions associated with barrier dysfunction, such as inflammatory bowel disease.
Collapse
Affiliation(s)
- Ana C Monteiro
- Department of Pathology and Laboratory Medicine, Epithelial Pathobiology Research Unit, Emory University, Atlanta, Georgia 30322, USA
| | | |
Collapse
|
50
|
Dekkers BGJ, Racké K, Schmidt M. Distinct PKA and Epac compartmentalization in airway function and plasticity. Pharmacol Ther 2012; 137:248-65. [PMID: 23089371 DOI: 10.1016/j.pharmthera.2012.10.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 10/09/2012] [Indexed: 12/15/2022]
Abstract
Asthma and chronic obstructive pulmonary disease (COPD) are obstructive lung diseases characterized by airway obstruction, airway inflammation and airway remodelling. Next to inflammatory cells and airway epithelial cells, airway mesenchymal cells, including airway smooth muscle cells and (myo)fibroblasts, substantially contribute to disease features by the release of inflammatory mediators, smooth muscle contraction, extracellular matrix deposition and structural changes in the airways. Current pharmacological treatment of both diseases intends to target the dynamic features of the endogenous intracellular suppressor cyclic AMP (cAMP). This review will summarize our current knowledge on cAMP and will emphasize on key discoveries and paradigm shifts reflecting the complex spatio-temporal nature of compartmentalized cAMP signalling networks in health and disease. As airway fibroblasts and airway smooth muscle cells are recognized as central players in the development and progression of asthma and COPD, we will focus on the role of cAMP signalling in their function in relation to airway function and plasticity. We will recapture on the recent identification of cAMP-sensing multi-protein complexes maintained by cAMP effectors, including A-kinase anchoring proteins (AKAPs), proteins kinase A (PKA), exchange protein directly activated by cAMP (Epac), cAMP-elevating seven-transmembrane (7TM) receptors and phosphodiesterases (PDEs) and we will report on findings indicating that the pertubation of compartmentalized cAMP signalling correlates with the pathopysiology of obstructive lung diseases. Future challenges include studies on cAMP dynamics and compartmentalization in the lung and the development of novel drugs targeting these systems for therapeutic interventions in chronic obstructive inflammatory diseases.
Collapse
Affiliation(s)
- Bart G J Dekkers
- Department of Molecular Pharmacology, University Center of Pharmacy, University of Groningen, The Netherlands.
| | | | | |
Collapse
|