1
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Li Z, Liu Q, Cai Y, Ye N, He Z, Yao Y, Ding Y, Wang P, Qi C, Zheng L, Wang L, Zhou J, Zhang QQ. EPAC inhibitor suppresses angiogenesis and tumor growth of triple-negative breast cancer. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167114. [PMID: 38447883 DOI: 10.1016/j.bbadis.2024.167114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 03/08/2024]
Abstract
AIMS Exchange protein directly activated by cAMP 1 (EPAC1), a major isoform of guanine nucleotide exchange factors, is highly expressed in vascular endothelia cells and regulates angiogenesis in the retina. High intratumor microvascular densities (MVD) resulting from angiogenesis is responsible for breast cancer development. Downregulation of EPAC1 in tumor cell reduces triple-negative breast cancer (TNBC)-induced angiogenesis. However, whether Epac1 expressed in vascular endothelial cells contributes to angiogenesis and tumor development of TNBC remains elusive. MAIN METHODS We employed NY0123, a previously identified potent EPAC inhibitor, to explore the anti-angiogenic biological role of EPAC1 in vitro and in vivo through vascular endothelial cells, rat aortic ring, Matrigel plug, and chick embryo chorioallantoic membrane (CAM) and yolk sac membrane (YSM) assays, as well as the in vivo xenograft tumor models of TNBC in both chick embryo and mice. KEY FINDINGS Inhibiting EPAC1 in vascular endothelial cells by NY0123 significantly suppresses angiogenesis and tumor growth of TNBC. In addition, NY0123 possesses a better inhibitory efficacy than ESI-09, a reported specific EPAC inhibitor tool compound. Importantly, inhibiting EPAC1 in vascular endothelia cells regulates the typical angiogenic signaling network, which is associated with not only vascular endothelial growth factor (VEGF)/vascular endothelial growth factor receptor-2 (VEGFR2) signaling, but also PI3K/AKT, MEK/ERK and Notch pathway. CONCLUSIONS Our findings support that EPAC1 may serve as an effective anti-angiogenic therapeutic target of TNBC, and EPAC inhibitor NY0123 has the therapeutic potential to be developed for the treatment of TNBC.
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Affiliation(s)
- Zishuo Li
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Qiao Liu
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yuhao Cai
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Na Ye
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Zinan He
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yuying Yao
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yi Ding
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Pingyuan Wang
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Cuiling Qi
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Lingyun Zheng
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Lijing Wang
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States.
| | - Qian-Qian Zhang
- School of Basic Medical Sciences, Guangdong Pharmaceutical University, Guangzhou 510006, China.
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2
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Zhang Q, Taniguchi S, So K, Tsuda M, Higuchi Y, Hashida M, Yamashita F. CREB is a potential marker associated with drug-induced liver injury: Identification and validation through transcriptome database analysis. J Toxicol Sci 2022; 47:337-348. [PMID: 35922923 DOI: 10.2131/jts.47.337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Drug-induced liver injury (DILI) is the main cause of failure in drug development and postapproval withdrawal. Although toxicogenomic techniques provide an unprecedented opportunity for mechanistic assessment and biomarker discovery, they are not suitable for the screening of large numbers of exploratory compounds in early drug discovery. Using a comprehensive analysis of toxicogenomics (TGx) data, we aimed to find DILI-relevant transcription factors (TFs) that could be incorporated into a reporter gene assay system. Gene set enrichment analysis (GSEA) of the Open TG-GATEs dataset highlighted 4 DILI-relevant TFs, including CREB, NRF2, ELK-1, and E2F. Using ten drugs with already assigned idiosyncratic toxicity (IDT) risks, reporter gene assays were conducted in HepG2 cells in the presence of the S9 mix. There were weak correlations between NRF2 activity and IDT risk, whereas strong correlations were observed between CREB activity and IDT risk. In addition, CREB activation associated with 3 Withdrawn/Black box Warning drugs was reversed by pretreatment with a PKA inhibitor. Collectively, we suggest that CREB might be a sensitive biomarker for DILI prediction, and its response to stress induced by high-risk drugs might be primarily regulated by the PKA/CREB signaling pathway.
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Affiliation(s)
- Qiyue Zhang
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Shiori Taniguchi
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Kanako So
- Department of Applied Pharmaceutics and Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Masahiro Tsuda
- Department of Applied Pharmaceutics and Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Yuriko Higuchi
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Mitsuru Hashida
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Fumiyoshi Yamashita
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University.,Department of Applied Pharmaceutics and Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyoto University
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3
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Maba IK, Cruz JV, Zampronio AR. Change in prostaglandin signaling during sickness syndrome hyperalgesia after ovariectomy in female rats. Behav Brain Res 2021; 410:113368. [PMID: 34000337 DOI: 10.1016/j.bbr.2021.113368] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 05/11/2021] [Accepted: 05/12/2021] [Indexed: 12/26/2022]
Abstract
The present study investigated hyperalgesia during sickness syndrome in female rats. Hyperalgesia was induced by an intraperitoneal injection of lipopolysaccharide (LPS) or an intracerebroventricular injection of prostaglandin E2 (PGE2). No differences were found in basal mechanical and thermal thresholds or in LPS-induced hyperalgesia in sham-operated animals in the diestrus or proestrus phase or in ovariectomized (OVX) animals. However, higher levels of PGE2 where found in the cerebrospinal fluid of OVX animals compared to sham-operated females. Intracerebroventricular injection of PGE2 produced rapid mechanical hyperalgesia in sham-operated rats while these responses were observed at later times in OVX animals. The protein kinase A (PKA) inhibitor H-89 reduced mechanical PGE2-induced hyperalgesia in OVX female rats, whereas no effect was observed in sham-operated animals. In contrast, the exchange protein activated by cyclic adenosine monophosphate (cAMP; Epac) inhibitor ESI-09 reduced mechanical PGE2-induced hyperalgesia, whereas no effect was observed in OVX animals. PGE2 also induced thermal hyperalgesia in sham-operated and OVX female rats and a similar effect of ESI-09 was observed. These results suggest that PGE2-induced hyperalgesia that is observed during sickness syndrome has different signaling mechanisms in cycling and OVX female rats involving the activation of the cAMP-Epac or cAMP-PKA pathways, respectively.
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Affiliation(s)
- I K Maba
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil
| | - J V Cruz
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil
| | - A R Zampronio
- Department of Pharmacology, Biological Sciences Section, Federal University of Paraná, Curitiba, PR, Brazil.
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4
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Maeda Y, Kikuchi R, Kawagoe J, Tsuji T, Koyama N, Yamaguchi K, Nakamura H, Aoshiba K. Anti-cancer strategy targeting the energy metabolism of tumor cells surviving a low-nutrient acidic microenvironment. Mol Metab 2020; 42:101093. [PMID: 33007425 PMCID: PMC7578269 DOI: 10.1016/j.molmet.2020.101093] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/17/2020] [Accepted: 09/24/2020] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE Tumor cells experience hypoxia, acidosis, and hypoglycemia. Metabolic adaptation to glucose shortage is essential to maintain tumor cells' survival because of their high glucose requirement. This study evaluated the hypothesis that acidosis might promote tumor survival during glucose shortage and if so, explored a novel drug targeting metabolic vulnerability to glucose shortage. METHODS Cell survival and bioenergetics metabolism were assessed in lung cancer cell lines. Our in-house small-molecule compounds were screened to identify those that kill cancer cells under low-glucose conditions. Cytotoxicity against non-cancerous cells was also assessed. Tumor growth was evaluated in vivo using a mouse engraft model. RESULTS Acidosis limited the cellular consumption of glucose and ATP, causing tumor cells to enter a metabolically dormant but energetically economic state, which promoted tumor cell survival during glucose deficiency. We identified ESI-09, a previously known exchange protein directly activated by cAMP (EAPC) inhibitor, as an anti-cancer compound that inhibited cancer cells under low-glucose conditions even when associated with acidosis. Bioenergetic studies showed that independent of EPAC inhibition, ESI-09 was a safer mitochondrial uncoupler than a classical uncoupler and created a futile cycle of mitochondrial respiration, leading to decreased ATP production, increased ATP dissipation, and fuel scavenging. Accordingly, ESI-09 exhibited more cytotoxic effects under low-glucose conditions than under normal glucose conditions. ESI-09 was also more effective than actively proliferating cells on quiescent glucose-restricted cells. Cisplatin showed opposite effects. ESI-09 inhibited tumor growth in lung cancer engraft mice. CONCLUSIONS This study highlights the acidosis-induced promotion of tumor survival during glucose shortage and demonstrates that ESI-09 is a novel potent anti-cancer mitochondrial uncoupler that targets a metabolic vulnerability to glucose shortage even when associated with acidosis. The higher cytotoxicity under lower-than-normal glucose conditions suggests that ESI-09 is safer than conventional chemotherapy, can target the metabolic vulnerability of tumor cells to low-glucose stress, and is applicable to many cancer cell types.
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Affiliation(s)
- Yuki Maeda
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan
| | - Ryota Kikuchi
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan; Department of Respiratory Medicine, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan
| | - Junichiro Kawagoe
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan; Department of Respiratory Medicine, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan
| | - Takao Tsuji
- Department of Medicine, Otsuki Municipal Hospital, 1255 Hanasaki, Otsuki-chou, Otsuki-shi, Yamanashi, 401-0015, Japan
| | - Nobuyuki Koyama
- Department of Clinical Oncology, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan
| | - Kazuhiro Yamaguchi
- Department of Respiratory Medicine, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan
| | - Hiroyuki Nakamura
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan
| | - Kazutetsu Aoshiba
- Department of Respiratory Medicine, Tokyo Medical University Ibaraki Medical Center, 3-20-1 Chuou, Ami-machi, Inashiki-gun, Ibaraki, 300-0395, Japan.
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5
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Liu W, Ha Y, Xia F, Zhu S, Li Y, Shi S, Mei FC, Merkley K, Vizzeri G, Motamedi M, Cheng X, Liu H, Zhang W. Neuronal Epac1 mediates retinal neurodegeneration in mouse models of ocular hypertension. J Exp Med 2020; 217:133574. [PMID: 31918438 PMCID: PMC7144517 DOI: 10.1084/jem.20190930] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/06/2019] [Accepted: 11/26/2019] [Indexed: 12/24/2022] Open
Abstract
Progressive loss of retinal ganglion cells (RGCs) leads to irreversible visual deficits in glaucoma. Here, we found that the level of cyclic AMP and the activity and expression of its mediator Epac1 were increased in retinas of two mouse models of ocular hypertension. Genetic depletion of Epac1 significantly attenuated ocular hypertension–induced detrimental effects in the retina, including vascular inflammation, neuronal apoptosis and necroptosis, thinning of ganglion cell complex layer, RGC loss, and retinal neuronal dysfunction. With bone marrow transplantation and various Epac1 conditional knockout mice, we further demonstrated that Epac1 in retinal neuronal cells (especially RGCs) was responsible for their death. Consistently, pharmacologic inhibition of Epac activity prevented RGC loss. Moreover, in vitro study on primary RGCs showed that Epac1 activation was sufficient to induce RGC death, which was mechanistically mediated by CaMKII activation. Taken together, these findings indicate that neuronal Epac1 plays a critical role in retinal neurodegeneration and suggest that Epac1 could be considered a target for neuroprotection in glaucoma.
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Affiliation(s)
- Wei Liu
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX.,Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yonju Ha
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Fan Xia
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Shuang Zhu
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Yi Li
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Shuizhen Shi
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Fang C Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Texas Health Science Center at Houston, Houston, TX
| | - Kevin Merkley
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Gianmarco Vizzeri
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Massoud Motamedi
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Texas Health Science Center at Houston, Houston, TX
| | - Hua Liu
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX
| | - Wenbo Zhang
- Department of Ophthalmology & Visual Sciences, University of Texas Medical Branch, Galveston, TX.,Departments of Neuroscience, Cell Biology & Anatomy, University of Texas Medical Branch, Galveston, TX
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6
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β-Adrenergic Receptors/Epac Signaling Increases the Size of the Readily Releasable Pool of Synaptic Vesicles Required for Parallel Fiber LTP. J Neurosci 2020; 40:8604-8617. [PMID: 33046543 DOI: 10.1523/jneurosci.0716-20.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 09/25/2020] [Accepted: 10/01/2020] [Indexed: 01/10/2023] Open
Abstract
The second messenger cAMP is an important determinant of synaptic plasticity that is associated with enhanced neurotransmitter release. Long-term potentiation (LTP) at parallel fiber (PF)-Purkinje cell (PC) synapses depends on a Ca2+-induced increase in presynaptic cAMP that is mediated by Ca2+-sensitive adenylyl cyclases. However, the upstream signaling and the downstream targets of cAMP involved in these events remain poorly understood. It is unclear whether cAMP generated by β-adrenergic receptors (βARs) is required for PF-PC LTP, although noradrenergic varicosities are apposed in PF-PC contacts. Guanine nucleotide exchange proteins directly activated by cAMP [Epac proteins (Epac 1-2)] are alternative cAMP targets to protein kinase A (PKA) and Epac2 is abundant in the cerebellum. However, whether Epac proteins participate in PF-PC LTP is not known. Immunoelectron microscopy demonstrated that βARs are expressed in PF boutons. Moreover, activation of these receptors through their agonist isoproterenol potentiated synaptic transmission in cerebellar slices from mice of either sex, an effect that was insensitive to the PKA inhibitors (H-89, KT270) but that was blocked by the Epac inhibitor ESI 05. Interestingly, prior activation of these βARs occluded PF-PC LTP, while the β1AR antagonist metoprolol blocked PF-PC LTP, which was also absent in Epac2 -/- mice. PF-PC LTP is associated with an increase in the size of the readily releasable pool (RRP) of synaptic vesicles, consistent with the isoproterenol-induced increase in vesicle docking in cerebellar slices. Thus, the βAR-mediated modulation of the release machinery and the subsequent increase in the size of the RRP contributes to PF-PC LTP.SIGNIFICANCE STATEMENT G-protein-coupled receptors modulate the release machinery, causing long-lasting changes in synaptic transmission that influence synaptic plasticity. Nevertheless, the mechanisms underlying synaptic responses to β-adrenergic receptor (βAR) activation remain poorly understood. An increase in the number of synaptic vesicles primed for exocytosis accounts for the potentiation of neurotransmitter release driven by βARs. This effect is not mediated by the canonical protein kinase A pathway but rather, through direct activation of the guanine nucleotide exchange protein Epac by cAMP. Interestingly, this βAR signaling via Epac is involved in long term potentiation at cerebellar granule cell-to-Purkinje cell synapses. Thus, the pharmacological activation of βARs modulates synaptic plasticity and opens therapeutic opportunities to control this phenomenon.
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7
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Lin Y, Ahmed W, He M, Xiang X, Tang R, Cui ZN. Synthesis and bioactivity of phenyl substituted furan and oxazole carboxylic acid derivatives as potential PDE4 inhibitors. Eur J Med Chem 2020; 207:112795. [PMID: 33002845 DOI: 10.1016/j.ejmech.2020.112795] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/30/2020] [Accepted: 08/30/2020] [Indexed: 11/19/2022]
Abstract
In this present study, a series of 5-phenyl-2-furan and 4-phenyl-2-oxazole derivatives were designed and synthesized as phosphodiesterase type 4 (PDE4) inhibitors. In vitro results showed that the synthesized compounds exhibited considerable inhibitory activity against PDE4B and blockade of LPS-induced TNF-α release. Among the designed compounds, Compound 5j exhibited lower IC50 value (1.4 μM) against PDE4 than parent rolipram (2.0 μM) in in vitro enzyme assay, which also displayed good in vivo activity in animal models of asthma/COPD and sepsis induced by LPS. Docking results suggested that introduction of methoxy group at para-position of phenyl ring, demonstrated good interaction with metal binding pocket domain of PDE4B, which was helpful to enhance inhibitory activity.
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Affiliation(s)
- Yinuo Lin
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China
| | - Wasim Ahmed
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China
| | - Min He
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China
| | - Xuwen Xiang
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China
| | - Riyuan Tang
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China; Department of Applied Chemistry, College of Materials and Energy, South China Agricultural University, Guangzhou 510642, China.
| | - Zi-Ning Cui
- State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources, Integrative Microbiology Research Centre, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, South China Agricultural University, Guangzhou, 510642, China; Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
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8
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Wang P, Luchowska-Stańska U, van Basten B, Chen H, Liu Z, Wiejak J, Whelan P, Morgan D, Lochhead E, Barker G, Rehmann H, Yarwood SJ, Zhou J. Synthesis and Biochemical Evaluation of Noncyclic Nucleotide Exchange Proteins Directly Activated by cAMP 1 (EPAC1) Regulators. J Med Chem 2020; 63:5159-5184. [PMID: 32340447 DOI: 10.1021/acs.jmedchem.9b02094] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Exchange proteins directly activated by cAMP (EPAC) play a central role in various biological functions, and activation of the EPAC1 protein has shown potential benefits for the treatment of various human diseases. Herein, we report the synthesis and biochemical evaluation of a series of noncyclic nucleotide EPAC1 activators. Several potent EPAC1 binders were identified including 25g, 25q, 25n, 25u, 25e, and 25f, which promote EPAC1 guanine nucleotide exchange factor activity in vitro. These agonists can also activate EPAC1 protein in cells, where they exhibit excellent selectivity toward EPAC over protein kinase A and G protein-coupled receptors. Moreover, 25e, 25f, 25n, and 25u exhibited improved selectivity toward activation of EPAC1 over EPAC2 in cells. Of these, 25u was found to robustly inhibit IL-6-activated signal transducer and activator of transcription 3 (STAT3) and subsequent induction of the pro-inflammatory vascular cell adhesion molecule 1 (VCAM1) cell-adhesion protein. These novel EPAC1 activators may therefore act as useful pharmacological tools for elucidation of EPAC function and promising drug leads for the treatment of relevant human diseases.
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Affiliation(s)
- Pingyuan Wang
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Urszula Luchowska-Stańska
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Boy van Basten
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Haiying Chen
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Zhiqing Liu
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Jolanta Wiejak
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Padraic Whelan
- Institute of Chemical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - David Morgan
- Institute of Chemical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Emma Lochhead
- Institute of Chemical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Graeme Barker
- Institute of Chemical Sciences, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Holger Rehmann
- Department of Molecular Cancer Research, Centre of Biomedical Genetics and Cancer Genomics Centre, University Medical Centre Utrecht, Utrecht 3584 CX, Netherlands
| | - Stephen J Yarwood
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Riccarton, Edinburgh EH14 4AS, U.K
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
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9
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Fu W, Nelson TS, Santos DF, Doolen S, Gutierrez JJ, Ye N, Zhou J, Taylor B. An NPY Y1 receptor antagonist unmasks latent sensitization and reveals the contribution of protein kinase A and Epac to chronic inflammatory pain. Pain 2019; 160:1754-1765. [PMID: 31335645 PMCID: PMC6903783 DOI: 10.1097/j.pain.0000000000001557] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Peripheral inflammation produces a long-lasting latent sensitization of spinal nociceptive neurons, that is, masked by tonic inhibitory controls. We explored mechanisms of latent sensitization with an established four-step approach: (1) induction of inflammation; (2) allow pain hypersensitivity to resolve; (3) interrogate latent sensitization with a channel blocker, mutant mouse, or receptor antagonist; and (4) disrupt compensatory inhibition with a receptor antagonist so as to reinstate pain hypersensitivity. We found that the neuropeptide Y Y1 receptor antagonist BIBO3304 reinstated pain hypersensitivity, indicative of an unmasking of latent sensitization. BIBO3304-evoked reinstatement was not observed in AC1 knockout mice and was prevented with intrathecal co-administration of a pharmacological blocker to the N-methyl-D-aspartate receptor (NMDAR), adenylyl cyclase type 1 (AC1), protein kinase A (PKA), transient receptor potential cation channel A1 (TRPA1), channel V1 (TRPV1), or exchange protein activated by cAMP (Epac1 or Epac2). A PKA activator evoked both pain reinstatement and touch-evoked pERK expression in dorsal horn; the former was prevented with intrathecal co-administration of a TRPA1 or TRPV1 blocker. An Epac activator also evoked pain reinstatement and pERK expression. We conclude that PKA and Epac are sufficient to maintain long-lasting latent sensitization of dorsal horn neurons that is kept in remission by the NPY-Y1 receptor system. Furthermore, we have identified and characterized 2 novel molecular signaling pathways in the dorsal horn that drive latent sensitization in the setting of chronic inflammatory pain: NMDAR→AC1→PKA→TRPA1/V1 and NMDAR→AC1→Epac1/2. New treatments for chronic inflammatory pain might either increase endogenous NPY analgesia or inhibit AC1, PKA, or Epac.
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Affiliation(s)
- Weisi Fu
- Department of Physiology, University of Kentucky Medical Center, Lexington KY, USA
| | - Tyler S. Nelson
- Department of Anesthesiology, Pittsburgh Center for Pain Research, and the Opiate Research Center at the University of Pittsburgh, University of Pittsburgh, Pittsburgh, PA USA
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA USA
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA USA
| | - Diogo F. Santos
- Department of Anesthesiology, Pittsburgh Center for Pain Research, and the Opiate Research Center at the University of Pittsburgh, University of Pittsburgh, Pittsburgh, PA USA
| | - Suzanne Doolen
- Department of Anesthesiology, Pittsburgh Center for Pain Research, and the Opiate Research Center at the University of Pittsburgh, University of Pittsburgh, Pittsburgh, PA USA
| | - Javier J.P. Gutierrez
- Department of Anesthesiology, Pittsburgh Center for Pain Research, and the Opiate Research Center at the University of Pittsburgh, University of Pittsburgh, Pittsburgh, PA USA
| | - Na Ye
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA
| | - Jia Zhou
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, USA
| | - Bradley Taylor
- Department of Physiology, University of Kentucky Medical Center, Lexington KY, USA
- Department of Anesthesiology, Pittsburgh Center for Pain Research, and the Opiate Research Center at the University of Pittsburgh, University of Pittsburgh, Pittsburgh, PA USA
- Center for Neuroscience at the University of Pittsburgh, Pittsburgh, PA USA
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10
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Griggs RB, Santos DF, Laird DE, Doolen S, Donahue RR, Wessel CR, Fu W, Sinha GP, Wang P, Zhou J, Brings S, Fleming T, Nawroth PP, Susuki K, Taylor BK. Methylglyoxal and a spinal TRPA1-AC1-Epac cascade facilitate pain in the db/db mouse model of type 2 diabetes. Neurobiol Dis 2019; 127:76-86. [PMID: 30807826 DOI: 10.1016/j.nbd.2019.02.019] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 02/21/2019] [Indexed: 12/21/2022] Open
Abstract
Painful diabetic neuropathy (PDN) is a devastating neurological complication of diabetes. Methylglyoxal (MG) is a reactive metabolite whose elevation in the plasma corresponds to PDN in patients and pain-like behavior in rodent models of type 1 and type 2 diabetes. Here, we addressed the MG-related spinal mechanisms of PDN in type 2 diabetes using db/db mice, an established model of type 2 diabetes, and intrathecal injection of MG in conventional C57BL/6J mice. Administration of either a MG scavenger (GERP10) or a vector overexpressing glyoxalase 1, the catabolic enzyme for MG, attenuated heat hypersensitivity in db/db mice. In C57BL/6J mice, intrathecal administration of MG produced signs of both evoked (heat and mechanical hypersensitivity) and affective (conditioned place avoidance) pain. MG-induced Ca2+ mobilization in lamina II dorsal horn neurons of C57BL/6J mice was exacerbated in db/db, suggestive of MG-evoked central sensitization. Pharmacological and/or genetic inhibition of transient receptor potential ankyrin subtype 1 (TRPA1), adenylyl cyclase type 1 (AC1), protein kinase A (PKA), or exchange protein directly activated by cyclic adenosine monophosphate (Epac) blocked MG-evoked hypersensitivity in C57BL/6J mice. Similarly, intrathecal administration of GERP10, or inhibitors of TRPA1 (HC030031), AC1 (NB001), or Epac (HJC-0197) attenuated hypersensitivity in db/db mice. We conclude that MG and sensitization of a spinal TRPA1-AC1-Epac signaling cascade facilitate PDN in db/db mice. Our results warrant clinical investigation of MG scavengers, glyoxalase inducers, and spinally-directed pharmacological inhibitors of a MG-TRPA1-AC1-Epac pathway for the treatment of PDN in type 2 diabetes.
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Affiliation(s)
- Ryan B Griggs
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America; Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States of America.
| | - Diogo F Santos
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Don E Laird
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Suzanne Doolen
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Renee R Donahue
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Caitlin R Wessel
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Weisi Fu
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Ghanshyam P Sinha
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America
| | - Pingyuan Wang
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Jia Zhou
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX, United States of America
| | - Sebastian Brings
- Department of Nuclear Medicine, University Hospital of Heidelberg, INF 400 Heidelberg, Germany; Department of Medicine and Clinical Chemistry, University Hospital of Heidelberg, INF 410 Heidelberg, Germany
| | - Thomas Fleming
- Department of Medicine and Clinical Chemistry, University Hospital of Heidelberg, INF 410 Heidelberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Peter P Nawroth
- Department of Medicine and Clinical Chemistry, University Hospital of Heidelberg, INF 410 Heidelberg, Germany; German Center for Diabetes Research (DZD), Neuherberg, Germany; Joint Heidelberg-IDC Translational Diabetes Program, Helmholtz Zentrum München, Neuherberg, Germany
| | - Keiichiro Susuki
- Department of Neuroscience, Cell Biology, and Physiology, Boonshoft School of Medicine, Wright State University, Dayton, OH, United States of America
| | - Bradley K Taylor
- Department of Physiology and Center for Analgesia Research Excellence, College of Medicine, University of Kentucky Medical Center, Lexington, KY, United States of America; Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA, United States of America.
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11
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Ramos-Alvarez I, Lee L, Jensen RT. Cyclic AMP-dependent protein kinase A and EPAC mediate VIP and secretin stimulation of PAK4 and activation of Na +,K +-ATPase in pancreatic acinar cells. Am J Physiol Gastrointest Liver Physiol 2019; 316:G263-G277. [PMID: 30520694 PMCID: PMC6397337 DOI: 10.1152/ajpgi.00275.2018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Rat pancreatic acinar cells possess only the p21-activated kinase (PAKs), PAK4 of the group II PAK, and it is activated by gastrointestinal hormones/neurotransmitters stimulating PLC and by a number of growth factors. However, little is known generally of cAMP agents causing PAK4 activation, and there are no studies with gastrointestinal hormones/neurotransmitters activating cAMP cascades. In the present study, we examined the ability of VIP and secretin, which stimulate cAMP generation in pancreatic acini, to stimulate PAK4 activation, the signaling cascades involved, and their possible role in activating sodium-potassium adenosine triphosphatase (Na+,K+-ATPase). PAK4 activation was compared with activation of the well-established cAMP target, cyclic AMP response element binding protein (CREB). Secretin-stimulated PAK4 activation was inhibited by KT-5720 and PKA Type II inhibitor (PKI), protein kinase A (PKA) inhibitors, whereas VIP activation was inhibited by ESI-09 and HJC0197, exchange protein directly activated by cAMP (EPAC) inhibitors. In contrast, both VIP/secretin-stimulated phosphorylation of CREB (pCREB) via EPAC activation; however, it was inhibited by the p44/42 inhibitor PD98059 and the p38 inhibitor SB202190. The specific EPAC agonist 8-CPT-2- O-Me-cAMP as well 8-Br-cAMP and forskolin stimulated PAK4 activation. Secretin/VIP activation of Na+,K+-ATPase, was inhibited by PAK4 inhibitors (PF-3758309, LCH-7749944). These results demonstrate PAK4 is activated in pancreatic acini by stimulation of both VIP-/secretin-preferring receptors, as is CREB. However, they differ in their signaling cascades. Furthermore, PAK4 activation is needed for Na+,K+ATPase activation, which mediates pancreatic fluid secretion. These results, coupled with recent studies reporting PAKs are involved in both pancreatitis/pancreatic cancer growth/enzyme secretion, show that PAK4, similar to PAK2, likely plays an important role in both pancreatic physiological/pathological responses. NEW & NOTEWORTHY Pancreatic acini possess only the group II p21-activated kinase, PAK4, which is activated by PLC-stimulating agents/growth factors and is important in enzyme-secretion/growth/pancreatitis. Little information exists on cAMP-activating agents stimulating group II PAKs. We studied ability/effect of cyclic AMP-stimulating agents [vasoactive intestinal polypeptide (VIP), secretin] on PAK4 activity in rat pancreatic-acini. Both VIP/secretin activated PAK4/CREB, but the cAMP signaling cascades differed for EPAC, MAPK, and PKA pathways. Both hormones require PAK4 activation to stimulate sodium-potassium adenosine triphosphatase activity. This study shows PAK4 plays an important role in VIP-/secretin-stimulated pancreatic fluid secretion and suggests it plays important roles in pancreatic acinar physiological/pathophysiological responses mediated by cAMP-activating agents.
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Affiliation(s)
- Irene Ramos-Alvarez
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Lingaku Lee
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - R. T. Jensen
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
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12
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Bai J, Jiang X, He M, Chan BCB, Wong AOL. Novel Mechanisms for IGF-I Regulation by Glucagon in Carp Hepatocytes: Up-Regulation of HNF1α and CREB Expression via Signaling Crosstalk for IGF-I Gene Transcription. Front Endocrinol (Lausanne) 2019; 10:605. [PMID: 31551932 PMCID: PMC6734168 DOI: 10.3389/fendo.2019.00605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 08/20/2019] [Indexed: 12/13/2022] Open
Abstract
Glucagon, a key hormone for glucose homeostasis, can exert functional crosstalk with somatotropic axis via modification of IGF-I expression. However, its effect on IGF-I regulation is highly variable in different studies and the mechanisms involved are largely unknown. Using grass carp as a model, the signal transduction and transcriptional mechanisms for IGF-I regulation by glucagon were examined in Cyprinid species. As a first step, the carp HNF1α, a liver-enriched transcription factor, was cloned and confirmed to be a single-copy gene expressed in the liver. In grass carp hepatocytes, glucagon treatment could elevate IGF-I, HNF1α, and CREB mRNA levels, induce CREB phosphorylation, and up-regulate HNF1α and CREB protein expression. The effects on IGF-I, HNF1α, and CREB gene expression were mediated by cAMP/PKA and PLC/IP3/PKC pathways with differential coupling with the MAPK and PI3K/Akt cascades. During the process, protein:protein interaction between HNF1α and CREB and recruitment of RNA Pol-II to IGF-I promoter also occurred with a rise in IGF-I primary transcript level. In parallel study to examine grass carp IGF-I promoter activity expressed in αT3 cells, similar pathways for post-receptor signaling were also confirmed in glucagon-induced IGF-I promoter activation and the trans-activating effect by glucagon was mediated by the binding sites for HNF1α and CREB located in the proximal region of IGF-I promoter. Our findings, as a whole, shed light on a previously undescribed mechanism for glucagon-induced IGF-I gene expression by increasing HNF1α and CREB production via functional crosstalk of post-receptor signaling. Probably, by protein:protein interaction between the two transcription factors and subsequent transactivation via their respective cis-acting elements in the IGF-I promoter, IGF-I gene transcription can be initiated by glucagon at the hepatic level.
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13
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Exchange Proteins Directly Activated by cAMP and Their Roles in Respiratory Syncytial Virus Infection. J Virol 2018; 92:JVI.01200-18. [PMID: 30185593 DOI: 10.1128/jvi.01200-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Accepted: 08/24/2018] [Indexed: 12/28/2022] Open
Abstract
Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in young children and high-risk adults. However, a specific treatment for this viral infection is not currently available. In this study, we discovered that an exchange protein directly activated by cyclic AMP (EPAC) can serve as a potential therapeutic target for RSV. In both lower and upper epithelial cells, treatment with EPAC inhibitor (ESI-09), but not protein kinase A inhibitor (H89), significantly inhibits RSV replication and proinflammatory cytokine/chemokine induction. In addition, RSV-activated transcriptional factors belonging to the NF-κB and IRF families are also suppressed by ESI-09. Through isoform-specific gene knockdown, we found that EPAC2, but not EPAC1, plays a dominant role in controlling RSV replication and virus-induced host responses. Experiments using both EPAC2 knockout and EPAC2-specific inhibitor support such roles of EPAC2. Therefore, EPAC2 is a promising therapeutic target to regulate RSV replication and associated inflammation.IMPORTANCE RSV is a serious public health problem, as it is associated with bronchiolitis, pneumonia, and asthma exacerbations. Currently no effective treatment or vaccine is available, and many molecular mechanisms regarding RSV-induced lung disease are still significantly unknown. This project aims to elucidate an important and novel function of a protein, called EPAC2, in RSV replication and innate inflammatory responses. Our results should provide an important insight into the development of new pharmacologic strategies against RSV infection, thereby reducing RSV-associated morbidity and mortality.
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14
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Drelich A, Judy B, He X, Chang Q, Yu S, Li X, Lu F, Wakamiya M, Popov V, Zhou J, Ksiazek T, Gong B. Exchange Protein Directly Activated by cAMP Modulates Ebola Virus Uptake into Vascular Endothelial Cells. Viruses 2018; 10:v10100563. [PMID: 30332733 PMCID: PMC6213290 DOI: 10.3390/v10100563] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/13/2018] [Accepted: 10/13/2018] [Indexed: 12/16/2022] Open
Abstract
Members of the family Filoviridae, including Ebola virus (EBOV) and Marburg virus (MARV), cause severe hemorrhagic fever in humans and nonhuman primates. Given their high lethality, a comprehensive understanding of filoviral pathogenesis is urgently needed. In the present studies, we revealed that the exchange protein directly activated by cAMP 1 (EPAC1) gene deletion protects vasculature in ex vivo explants from EBOV infection. Importantly, pharmacological inhibition of EPAC1 using EPAC-specific inhibitors (ESIs) mimicked the EPAC1 knockout phenotype in the ex vivo model. ESI treatment dramatically decreased EBOV infectivity in both ex vivo vasculature and in vitro vascular endothelial cells (ECs). Furthermore, postexposure protection of ECs against EBOV infection was conferred using ESIs. Protective efficacy of ESIs in ECs was observed also in MARV infection. Additional studies using a vesicular stomatitis virus pseudotype that expresses EBOV glycoprotein (EGP-VSV) confirmed that ESIs reduced infection in ECs. Ultrastructural studies suggested that ESIs blocked EGP-VSV internalization via inhibition of macropinocytosis. The inactivation of EPAC1 affects the early stage of viral entry after viral binding to the cell surface, but before early endosome formation, in a phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)-dependent manner. Our study delineated a new critical role of EPAC1 during EBOV uptake into ECs.
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Affiliation(s)
- Aleksandra Drelich
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Barbara Judy
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Xi He
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Cardiovascular Surgery, Changhai Institute of Cardiovascular Surgery, Shanghai 200433, China.
| | - Qing Chang
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Shangyi Yu
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
- Department of Cardiovascular Surgery, Changhai Institute of Cardiovascular Surgery, Shanghai 200433, China.
| | - Xiang Li
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Fanglin Lu
- Department of Cardiovascular Surgery, Changhai Institute of Cardiovascular Surgery, Shanghai 200433, China.
| | - Maki Wakamiya
- Department of Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Vsevolod Popov
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Jia Zhou
- Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Thomas Ksiazek
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
| | - Bin Gong
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555, USA.
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15
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Sun Z, Hou D, Liu S, Fu W, Wang J, Liang Z. Norepinephrine inhibits the cytotoxicity of NK92‑MI cells via the β2‑adrenoceptor/cAMP/PKA/p‑CREB signaling pathway. Mol Med Rep 2018; 17:8530-8535. [PMID: 29658580 DOI: 10.3892/mmr.2018.8872] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Accepted: 03/07/2018] [Indexed: 11/06/2022] Open
Abstract
Norepinephrine (NE) can regulate natural killer (NK) cell activity, but the mechanism remains unclear. In the present study the roles of adrenergic receptors (ARs) in inhibiting NK92‑MI cells‑mediated cytotoxicity by NE were investigated. To examine the effect of NE on NK92‑MI cytotoxicity, a lactate dehydrogenase‑release cytotoxicity assay was used to determine the cytotoxicity of NK92‑MI cells against K562 cells. To evaluate the possible function of the α, β1 and β2 AR in mediating NE‑induced effects, NK92‑MI cells were pre‑incubated with phenol‑amine, CGP20712A and ICI118551 prior to stimulation by NE. To evaluate the role of cyclic adenosine monophosphate (cAMP)‑protein kinase A (PKA) signaling pathway in the inhibitory effect on cytotoxicity of NK92‑MI cell by NE, NK92‑MI cells were pre‑incubated with PKA inhibitor Rp‑8‑Br‑cAMP prior to stimulation by NE. It was demonstrated that NE decreased cytotoxicity and downregulated the expression of perforin, granzyme B and interferon (IFN)‑γ of NK92‑MI cells in a dose‑dependent manner. Blocking NE functional receptors by ARs antagonists, particularly of β2 AR antagonist, suppressed the inhibitory effect of NE on cytotoxicity and expression of perforin, granzyme B, IFN‑γ of NK92‑MI cells significantly. Blockade of β2 AR in NE treated NK92‑MI cells resulted in a reduction of the expression of phosphorylated (p)‑cAMP‑responsive element‑binding protein (CREB) and intracellular cAMP concentration. Inhibiting the activity of PKA by Rp‑8‑Br‑cAMP in NE treated NK92‑MI cells resulted in increased cytotoxicity. The results of the present study suggest that NE can inhibit cytotoxicity and expression of perforin, granzyme B, IFN‑γ of NK92‑MI cell mainly via the β2‑AR/cAMP/PKA/p‑CREB signaling pathway.
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Affiliation(s)
- Zan Sun
- Center of Experiment and Technology, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Diandong Hou
- Basic Medical College, Liaoning University of Traditional Chinese Medicine, Shenyang, Liaoning 110847, P.R. China
| | - Shuli Liu
- Department of Pathology, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Weixin Fu
- Center of Experiment and Technology, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Jiahui Wang
- Center of Experiment and Technology, China Medical University, Shenyang, Liaoning 110122, P.R. China
| | - Zaifu Liang
- Center of Experiment and Technology, China Medical University, Shenyang, Liaoning 110122, P.R. China
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16
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Robichaux WG, Cheng X. Intracellular cAMP Sensor EPAC: Physiology, Pathophysiology, and Therapeutics Development. Physiol Rev 2018; 98:919-1053. [PMID: 29537337 PMCID: PMC6050347 DOI: 10.1152/physrev.00025.2017] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/13/2022] Open
Abstract
This review focuses on one family of the known cAMP receptors, the exchange proteins directly activated by cAMP (EPACs), also known as the cAMP-regulated guanine nucleotide exchange factors (cAMP-GEFs). Although EPAC proteins are fairly new additions to the growing list of cAMP effectors, and relatively "young" in the cAMP discovery timeline, the significance of an EPAC presence in different cell systems is extraordinary. The study of EPACs has considerably expanded the diversity and adaptive nature of cAMP signaling associated with numerous physiological and pathophysiological responses. This review comprehensively covers EPAC protein functions at the molecular, cellular, physiological, and pathophysiological levels; and in turn, the applications of employing EPAC-based biosensors as detection tools for dissecting cAMP signaling and the implications for targeting EPAC proteins for therapeutic development are also discussed.
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Affiliation(s)
- William G Robichaux
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center , Houston, Texas
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17
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Hafizur RM, Maryam K, Hameed A, zaheer L, Bano S, Sumbul S, Sana A, Saleem R, Naz S, Waraich RS, Ul-Haq Z, Faizi S. Insulin releasing effect of some pure compounds from Moringa oleifera on mice islets. Med Chem Res 2018. [DOI: 10.1007/s00044-018-2157-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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18
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Sonawane YA, Zhu Y, Garrison JC, Ezell EL, Zahid M, Cheng X, Natarajan A. Structure-Activity Relationship Studies with Tetrahydroquinoline Analogs as EPAC Inhibitors. ACS Med Chem Lett 2017; 8:1183-1187. [PMID: 29375750 PMCID: PMC5774307 DOI: 10.1021/acsmedchemlett.7b00358] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 10/02/2017] [Indexed: 12/18/2022] Open
Abstract
![]()
EPAC proteins are
therapeutic targets for the potential treatment
of cardiac hypertrophy and cancer metastasis. Several laboratories
use a tetrahydroquinoline analog, CE3F4, to dissect the role of EPAC1
in various disease states. Here, we report SAR studies with tetrahydroquinoline
analogs that explore various functional groups. The most potent EPAC
inhibitor 12a exists as a mixture of inseparable E (major) and Z (minor) rotamers. The rotation
about the N-formyl group indeed impacts the activity
against EPAC.
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Affiliation(s)
| | - Yingmin Zhu
- Department of Integrative Biology and Pharmacology and Texas Therapeutics Institute, University of Texas Health Science Center, Houston, Texas 77030, United States
| | | | | | | | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology and Texas Therapeutics Institute, University of Texas Health Science Center, Houston, Texas 77030, United States
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19
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Liu Z, Zhu Y, Chen H, Wang P, Mei FC, Ye N, Cheng X, Zhou J. Structure-activity relationships of 2-substituted phenyl-N-phenyl-2-oxoacetohydrazonoyl cyanides as novel antagonists of exchange proteins directly activated by cAMP (EPACs). Bioorg Med Chem Lett 2017; 27:5163-5166. [PMID: 29100797 DOI: 10.1016/j.bmcl.2017.10.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/19/2017] [Accepted: 10/22/2017] [Indexed: 11/24/2022]
Abstract
Exchange proteins directly activated by cAMP (EPACs) are critical cAMP-dependent signaling pathway mediators that play important roles in cancer, diabetes, heart failure, inflammations, infections, neurological disorders and other human diseases. EPAC specific modulators are urgently needed to explore EPAC's physiological function, mechanism of action and therapeutic applications. On the basis of a previously identified EPAC specific inhibitor hit ESI-09, herein we have designed and synthesized a novel series of 2-substituted phenyl-N-phenyl-2-oxoacetohydrazonoyl cyanides as potent EPAC inhibitors. Compound 31 (ZL0524) has been discovered as the most potent EPAC inhibitor with IC50 values of 3.6 µM and 1.2 µM against EPAC1 and EPAC2, respectively. Molecular docking of 31 onto an active EPAC2 structure predicts that 31 occupies the hydrophobic pocket in cAMP binding domain (CBD) and also opens up new space leading to the solvent region. These findings provide inspirations for discovering next generation of EPAC inhibitors.
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Affiliation(s)
- Zhiqing Liu
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, United States
| | - Yingmin Zhu
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, 7000 Fannin St #1200, Houston, TX 77030, United States
| | - Haiying Chen
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, United States
| | - Pingyuan Wang
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, United States
| | - Fang C Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, 7000 Fannin St #1200, Houston, TX 77030, United States
| | - Na Ye
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, United States
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, 7000 Fannin St #1200, Houston, TX 77030, United States.
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, 301 University Blvd, Galveston, TX 77555, United States.
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20
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Rational design of conformationally constrained oxazolidinone-fused 1,2,3,4-tetrahydroisoquinoline derivatives as potential PDE4 inhibitors. Bioorg Med Chem 2017; 25:5709-5717. [PMID: 28888661 DOI: 10.1016/j.bmc.2017.08.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 08/22/2017] [Accepted: 08/27/2017] [Indexed: 12/24/2022]
Abstract
Improvement of subtype selectivity of an inhibitor's binding activity using the conformational restriction approach has become an effective strategy in drug discovery. In this study, we applied this approach to PDE4 inhibitors and designed a series of novel oxazolidinone-fused 1,2,3,4-tetrahydroisoquinoline derivatives as conformationally restricted analogues of rolipram. The bioassay results demonstrated the oxazolidinone-fused tetrahydroisoquinoline derivatives exhibited moderate to good inhibitory activity against PDE4B and high selectivity for PDE4B/PDE4D. Among these derivatives, compound 12 showed both the strongest inhibition activity (IC50=0.60μM) as well as good selectivity against PDE4B and good in vivo activity in animal models of asthma/COPD and sepsis induced by LPS. The primary SAR study showed that restricting the conformation of the catechol moiety in rolipram with the scaffold of oxazolidinone-fused tetrahydroisoquinoline could lead to an increase in selectivity for PDE4B over PDE4D, which was consistent with the observed docking simulation.
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21
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Zhu Y, Mei F, Luo P, Cheng X. A cell-based, quantitative and isoform-specific assay for exchange proteins directly activated by cAMP. Sci Rep 2017; 7:6200. [PMID: 28740152 PMCID: PMC5524698 DOI: 10.1038/s41598-017-06432-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 06/13/2017] [Indexed: 12/17/2022] Open
Abstract
Extensive functional studies of the exchange protein directly activated by cAMP (EPAC) family of signaling molecules have demonstrated that EPAC proteins play a fundamental role in several physiological and pathophysiological responses, therefore are attractive drug targets. In this report, the development of a cell-based, medium to high throughput screening assay that is capable of monitoring EPAC-mediated activation of cellular Rap1 in an isoform-specific manner is described. This assay adapts a conventional ELISA format with immobilized RalGDS-RBD as a bait to selectively capture GTP-bound active Rap1. As a result, it fills an urgent need for a cell-based EPAC assay that can be conveniently performed using microtiter plates for the discovery and/or validation of isoform-specific EPAC agonists and antagonists.
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Affiliation(s)
- Yingmin Zhu
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Health Science Center, Houston, Texas, USA
| | - Fang Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Health Science Center, Houston, Texas, USA
| | - Pei Luo
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Health Science Center, Houston, Texas, USA
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Health Science Center, Houston, Texas, USA.
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22
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Wang P, Liu Z, Chen H, Ye N, Cheng X, Zhou J. Exchange proteins directly activated by cAMP (EPACs): Emerging therapeutic targets. Bioorg Med Chem Lett 2017; 27:1633-1639. [PMID: 28283242 PMCID: PMC5397994 DOI: 10.1016/j.bmcl.2017.02.065] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/07/2017] [Accepted: 02/26/2017] [Indexed: 11/22/2022]
Abstract
Exchange proteins directly activated by cAMP (EPACs) are critical cAMP-dependent signaling pathway mediators. The discovery of EPAC proteins has significantly facilitated understanding on cAMP-dependent signaling pathway and efforts along this line open new avenues for developing novel therapeutics for cancer, diabetes, heart failure, inflammation, infections, neurological disorders and other human diseases. Over the past decade, important progress has been made in the identification of EPAC agonists, antagonists and their biological and pharmacological applications. In this review, we briefly summarize recently reported novel functions of EPACs and the discovery of their small molecule modulators. The challenges and future perspectives are also discussed.
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Affiliation(s)
- Pingyuan Wang
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Zhiqing Liu
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Haiying Chen
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Na Ye
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, University of Texas Health Science Center, Houston, TX 77030, United States
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States.
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23
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Ye N, Zhu Y, Liu Z, Mei FC, Chen H, Wang P, Cheng X, Zhou J. Identification of novel 2-(benzo[d]isoxazol-3-yl)-2-oxo-N-phenylacetohydrazonoyl cyanide analoguesas potent EPAC antagonists. Eur J Med Chem 2017; 134:62-71. [PMID: 28399451 DOI: 10.1016/j.ejmech.2017.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 03/30/2017] [Accepted: 04/01/2017] [Indexed: 12/28/2022]
Abstract
Two series of novel EPAC antagonists are designed, synthesized and evaluated in an effort to develop diversified analogues based on the scaffold of the previously identified high-throughput (HTS) hit 1 (ESI-09). Further SAR studies reveal that the isoxazole ring A of 1 can tolerate chemical modifications with either introduction of flexible electron-donating substitutions or structurally restrictedly fusing with a phenyl ring, leading to identification of several more potent and diversified EPAC antagonists (e.g., 10 (NY0617), 14 (NY0460), 26 (NY0725), 32 (NY0561), and 33 (NY0562)) with low micromolar inhibitory activities. Molecular docking studies on compounds 10 and 33 indicate that these two series of compounds bind at a similar site with substantially different interactions with the EPAC proteins. The findings may serve as good starting points for the development of more potent EPAC antagonists as valuable pharmacological probes or potential drug candidates.
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Affiliation(s)
- Na Ye
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States; Department of Medicinal Chemistry, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Yingmin Zhu
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, Houston, TX 77030, United States
| | - Zhiqing Liu
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Fang C Mei
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, Houston, TX 77030, United States
| | - Haiying Chen
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Pingyuan Wang
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The University of Texas Health Science Center, Houston, TX 77030, United States.
| | - Jia Zhou
- Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, TX 77555, United States.
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24
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Fujita T, Umemura M, Yokoyama U, Okumura S, Ishikawa Y. The role of Epac in the heart. Cell Mol Life Sci 2017; 74:591-606. [PMID: 27549789 PMCID: PMC11107744 DOI: 10.1007/s00018-016-2336-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Revised: 07/21/2016] [Accepted: 08/09/2016] [Indexed: 02/08/2023]
Abstract
As one of the most important second messengers, 3',5'-cyclic adenosine monophosphate (cAMP) mediates various extracellular signals including hormones and neurotransmitters, and induces appropriate responses in diverse types of cells. Since cAMP was formerly believed to transmit signals through only two direct target molecules, protein kinase A and the cyclic nucleotide-gated channel, the sensational discovery in 1998 of another novel direct effecter of cAMP [exchange proteins directly activated by cAMP (Epac)] attracted a great deal of scientific interest in cAMP signaling. Numerous studies on Epac have since disclosed its important functions in various tissues in the body. Recently, observations of genetically manipulated mice in various pathogenic models have begun to reveal the in vivo significance of previous in vitro or cellular-level findings. Here, we focused on the function of Epac in the heart. Accumulating evidence has revealed that both Epac1 and Epac2 play important roles in the structure and function of the heart under physiological and pathological conditions. Accordingly, developing the ability to regulate cAMP-mediated signaling through Epac may lead to remarkable new therapies for the treatment of cardiac diseases.
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Affiliation(s)
- Takayuki Fujita
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
| | - Masanari Umemura
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Utako Yokoyama
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Satoshi Okumura
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan
- Tsurumi University School of Dental Medicine, Yokohama, Japan
| | - Yoshihiro Ishikawa
- Cardiovascular Research Institute, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
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25
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Sapio L, Gallo M, Illiano M, Chiosi E, Naviglio D, Spina A, Naviglio S. The Natural cAMP Elevating Compound Forskolin in Cancer Therapy: Is It Time? J Cell Physiol 2016; 232:922-927. [PMID: 27739063 DOI: 10.1002/jcp.25650] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 10/12/2016] [Indexed: 12/24/2022]
Abstract
Cancer is a major public health problem and the second leading cause of mortality around the world. Although continuous advances in the science of oncology and cancer research are now leading to improved outcomes for many cancer patients, novel cancer treatment options are strongly demanded. Naturally occurring compounds from a variety of vegetables, fruits, and medicinal plants have been shown to exhibit various anticancer properties in a number of in vitro and in vivo studies and represent an attractive research area for the development of new therapeutic strategies to fight cancer. Forskolin is a diterpene produced by the roots of the Indian plant Coleus forskohlii. The natural compound forskolin has been used for centuries in traditional medicine and its safety has also been documented in conventional modern medicine. Forskolin directly activates the adenylate cyclase enzyme, that generates cAMP from ATP, thus, raising intracellular cAMP levels. Notably, cAMP signaling, through the PKA-dependent and/or -independent pathways, is very relevant to cancer and its targeting has shown a number of antitumor effects, including the induction of mesenchymal-to-epithelial transition, inhibition of cell growth and migration and enhancement of sensitivity to conventional antitumor drugs in cancer cells. Here, we describe some features of cAMP signaling that are relevant to cancer biology and address the state of the art concerning the natural cAMP elevating compound forskolin and its perspectives as an effective anticancer agent. J. Cell. Physiol. 232: 922-927, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Luigi Sapio
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Medical School, Naples, Italy
| | - Monica Gallo
- Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples, Italy
| | - Michela Illiano
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Medical School, Naples, Italy
| | - Emilio Chiosi
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Medical School, Naples, Italy
| | - Daniele Naviglio
- Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
| | - Annamaria Spina
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Medical School, Naples, Italy
| | - Silvio Naviglio
- Department of Biochemistry, Biophysics and General Pathology, Second University of Naples, Medical School, Naples, Italy
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26
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Exchange factors directly activated by cAMP mediate melanocortin 4 receptor-induced gene expression. Sci Rep 2016; 6:32776. [PMID: 27612207 PMCID: PMC5017209 DOI: 10.1038/srep32776] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 08/15/2016] [Indexed: 01/16/2023] Open
Abstract
Gs protein-coupled receptors regulate many vital body functions by activation of cAMP response elements (CRE) via cAMP-dependent kinase A (PKA)-mediated phosphorylation of the CRE binding protein (CREB). Melanocortin 4 receptors (MC4R) are prototypical Gs-coupled receptors that orchestrate the hypothalamic control of food-intake and metabolism. Remarkably, the significance of PKA for MC4R-induced CRE-dependent transcription in hypothalamic cells has not been rigorously interrogated yet. In two hypothalamic cell lines, we observed that blocking PKA activity had only weak or no effects on reporter gene expression. In contrast, inhibitors of exchange factors directly activated by cAMP-1/2 (EPAC-1/2) mitigated MC4R-induced CRE reporter activation and mRNA induction of the CREB-dependent genes c-fos and thyrotropin-releasing hormone. Furthermore, we provide first evidence that extracellular-regulated kinases-1/2 (ERK-1/2) activated by EPACs and not PKA are the elusive CREB kinases responsible for MC4R-induced CREB/CRE activation in hypothalamic cells. Overall, these data emphasize the pivotal role of EPACs rather than PKA in hypothalamic gene expression elicited by a prototypical Gs-coupled receptor.
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27
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Cao S, Bian Z, Zhu X, Shen SR. Effect of Epac1 on pERK and VEGF Activation in Postoperative Persistent Pain in Rats. J Mol Neurosci 2016; 59:554-64. [DOI: 10.1007/s12031-016-0776-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 06/02/2016] [Indexed: 02/01/2023]
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28
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Wild CT, Zhu Y, Na Y, Mei F, Ynalvez MA, Chen H, Cheng X, Zhou J. Functionalized N,N-Diphenylamines as Potent and Selective EPAC2 Inhibitors. ACS Med Chem Lett 2016; 7:460-4. [PMID: 27190593 DOI: 10.1021/acsmedchemlett.5b00477] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/28/2016] [Indexed: 02/08/2023] Open
Abstract
N,N-Diphenylamines were discovered as potent and selective EPAC2 inhibitors. A study was conducted to determine the structure-activity relationships in a series of inhibitors of which several compounds displayed submicromolar potencies. Selectivity over the related EPAC1 protein was also demonstrated. Computational modeling reveals an allosteric site that is distinct from the cAMP binding domain shared by both EPAC isoforms, providing a theory with regards to subtype selectivity.
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Affiliation(s)
- Christopher T. Wild
- Chemical
Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Yingmin Zhu
- Department
of Integrative Biology and Pharmacology and Texas Therapeutics Institute, University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Ye Na
- Chemical
Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Fang Mei
- Department
of Integrative Biology and Pharmacology and Texas Therapeutics Institute, University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Marcus A. Ynalvez
- Chemical
Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Haiying Chen
- Chemical
Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Xiaodong Cheng
- Department
of Integrative Biology and Pharmacology and Texas Therapeutics Institute, University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Jia Zhou
- Chemical
Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
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29
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Wang Z, Liu D, Varin A, Nicolas V, Courilleau D, Mateo P, Caubere C, Rouet P, Gomez AM, Vandecasteele G, Fischmeister R, Brenner C. A cardiac mitochondrial cAMP signaling pathway regulates calcium accumulation, permeability transition and cell death. Cell Death Dis 2016; 7:e2198. [PMID: 27100892 PMCID: PMC4855650 DOI: 10.1038/cddis.2016.106] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 03/17/2016] [Accepted: 03/21/2016] [Indexed: 12/19/2022]
Abstract
Although cardiac cytosolic cyclic 3',5'-adenosine monophosphate (cAMP) regulates multiple processes, such as beating, contractility, metabolism and apoptosis, little is known yet on the role of this second messenger within cardiac mitochondria. Using cellular and subcellular approaches, we demonstrate here the local expression of several actors of cAMP signaling within cardiac mitochondria, namely a truncated form of soluble AC (sACt) and the exchange protein directly activated by cAMP 1 (Epac1), and show a protective role for sACt against cell death, apoptosis as well as necrosis in primary cardiomyocytes. Upon stimulation with bicarbonate (HCO3(-)) and Ca(2+), sACt produces cAMP, which in turn stimulates oxygen consumption, increases the mitochondrial membrane potential (ΔΨm) and ATP production. cAMP is rate limiting for matrix Ca(2+) entry via Epac1 and the mitochondrial calcium uniporter and, as a consequence, prevents mitochondrial permeability transition (MPT). The mitochondrial cAMP effects involve neither protein kinase A, Epac2 nor the mitochondrial Na(+)/Ca(2+) exchanger. In addition, in mitochondria isolated from failing rat hearts, stimulation of the mitochondrial cAMP pathway by HCO3(-) rescued the sensitization of mitochondria to Ca(2+)-induced MPT. Thus, our study identifies a link between mitochondrial cAMP, mitochondrial metabolism and cell death in the heart, which is independent of cytosolic cAMP signaling. Our results might have implications for therapeutic prevention of cell death in cardiac pathologies.
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Affiliation(s)
- Z Wang
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - D Liu
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - A Varin
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - V Nicolas
- UMS-IPSIT, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - D Courilleau
- UMS-IPSIT, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - P Mateo
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - C Caubere
- INSERM I2MC, UMR 1048, Université Paul Sabatier, Toulouse, France
| | - P Rouet
- INSERM I2MC, UMR 1048, Université Paul Sabatier, Toulouse, France
| | - A-M Gomez
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - G Vandecasteele
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - R Fischmeister
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.,UMS-IPSIT, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
| | - C Brenner
- INSERM UMR-S 1180, Faculté de Pharmacie, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France.,UMS-IPSIT, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France
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30
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Ye N, Zhu Y, Chen H, Liu Z, Mei FC, Wild C, Chen H, Cheng X, Zhou J. Structure-Activity Relationship Studies of Substituted 2-(Isoxazol-3-yl)-2-oxo-N'-phenyl-acetohydrazonoyl Cyanide Analogues: Identification of Potent Exchange Proteins Directly Activated by cAMP (EPAC) Antagonists. J Med Chem 2015; 58:6033-47. [PMID: 26151319 DOI: 10.1021/acs.jmedchem.5b00635] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Exchange proteins directly activated by cAMP (EPAC) as guanine nucleotide exchange factors mediate the effects of the pivotal second messenger cAMP, thereby regulating a wide variety of intracellular physiological and pathophysiological processes. A series of novel 2-(isoxazol-3-yl)-2-oxo-N'-phenyl-acetohydrazonoyl cyanide EPAC antagonists was synthesized and evaluated in an effort to optimize properties of the previously identified high-throughput (HTS) hit 1 (ESI-09). Structure-activity relationship (SAR) analysis led to the discovery of several more active EPAC antagonists (e.g., 22 (HJC0726), 35 (NY0123), and 47 (NY0173)) with low micromolar inhibitory activity. These inhibitors may serve as valuable pharmacological probes to facilitate our efforts in elucidating the biological functions of EPAC and developing potential novel therapeutics against human diseases. Our SAR results have also revealed that further modification at the 3-, 4-, and 5-positions of the phenyl ring as well as the 5-position of the isoxazole moiety may allow for the development of more potent EPAC antagonists.
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Affiliation(s)
- Na Ye
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Yingmin Zhu
- ‡Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Haijun Chen
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Zhiqing Liu
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Fang C Mei
- ‡Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Christopher Wild
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Haiying Chen
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
| | - Xiaodong Cheng
- ‡Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center, Houston, Texas 77030, United States
| | - Jia Zhou
- †Chemical Biology Program, Department of Pharmacology and Toxicology, University of Texas Medical Branch, Galveston, Texas 77555, United States
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31
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Banerjee U, Cheng X. Exchange protein directly activated by cAMP encoded by the mammalian rapgef3 gene: Structure, function and therapeutics. Gene 2015; 570:157-67. [PMID: 26119090 PMCID: PMC4556420 DOI: 10.1016/j.gene.2015.06.063] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2015] [Accepted: 06/23/2015] [Indexed: 01/08/2023]
Abstract
Mammalian exchange protein directly activated by cAMP isoform 1 (EPAC1), encoded by the RAPGEF3 gene, is one of the two-membered family of cAMP sensors that mediate the intracellular functions of cAMP by acting as guanine nucleotide exchange factors for the Ras-like Rap small GTPases. Extensive studies have revealed that EPAC1-mediated cAMP signaling is highly coordinated spatiotemporally through the formation of dynamic signalosomes by interacting with a diverse array of cellular partners. Recent functional analyses of genetically engineered mouse models further suggest that EPAC1 functions as an important stress response switch and is involved in pathophysiological conditions of cardiac stresses, chronic pain, cancer and infectious diseases. These findings, coupled with the development of EPAC specific small molecule modulators, validate EPAC1 as a promising target for therapeutic interventions. Human gene RAPGEF3 encodes for EPAC1 protein. Along with PKA, CNG & HCN, EPAC is an important cAMP sensor. Selective modulators of EPAC1 have been developed for use as pharmacological probes. Formation of EPAC1 signalosomes allows spatiotemporal control of cAMP signaling. EPAC1 is implicated in major pathophysiological conditions and is an attractive therapeutic target.
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Affiliation(s)
- Upasana Banerjee
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Health Science Center, Houston, TX 77030, United States
| | - Xiaodong Cheng
- Department of Integrative Biology and Pharmacology, Texas Therapeutics Institute, The Brown Foundation Institute of Molecular Medicine for the Prevention of Human Diseases, University of Health Science Center, Houston, TX 77030, United States.
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32
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Schwede F, Bertinetti D, Langerijs CN, Hadders MA, Wienk H, Ellenbroek JH, de Koning EJP, Bos JL, Herberg FW, Genieser HG, Janssen RAJ, Rehmann H. Structure-guided design of selective Epac1 and Epac2 agonists. PLoS Biol 2015; 13:e1002038. [PMID: 25603503 PMCID: PMC4300089 DOI: 10.1371/journal.pbio.1002038] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Accepted: 12/03/2014] [Indexed: 12/25/2022] Open
Abstract
The second messenger cAMP is known to augment glucose-induced insulin secretion. However, its downstream targets in pancreatic β-cells have not been unequivocally determined. Therefore, we designed cAMP analogues by a structure-guided approach that act as Epac2-selective agonists both in vitro and in vivo. These analogues activate Epac2 about two orders of magnitude more potently than cAMP. The high potency arises from increased affinity as well as increased maximal activation. Crystallographic studies demonstrate that this is due to unique interactions. At least one of the Epac2-specific agonists, Sp-8-BnT-cAMPS (S-220), enhances glucose-induced insulin secretion in human pancreatic cells. Selective targeting of Epac2 is thus proven possible and may be an option in diabetes treatment. cAMP is a small molecule produced by cells that activates proteins involved in a wide range of biological processes, including olfaction, pacemaker activity, regulation of gene expression, insulin secretion, and many others. In the case of insulin secretion, cAMP seems to impinge on different stages of the signalling cascade to regulate secretory activity in pancreatic β-cells. Here we have developed a chemically modified version of cAMP that specifically only activates Epac2, one of the cAMP-responsive proteins in this cascade. Furthermore, our cAMP analogue activates Epac2 more potently than cAMP itself does. We have determined several crystal structures of Epac2 in complex with cAMP analogues to help us explain the molecular basis of the observed selectivity and the strong activation potential. In addition, we were able to show that the analogue is able to potentiate glucose-induced secretion of insulin from human pancreatic islets. The principal challenge during this study was identifying and understanding small differences in the cAMP-binding domains of cAMP-regulated proteins and matching these differences with suitable modifications of the cAMP molecule. A newly developed analogue of cAMP that selectively activates Epac2 can potentiate glucose-induced insulin secretion from human pancreatic β-cells.
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Affiliation(s)
| | | | | | - Michael A. Hadders
- Department of Chemistry, Laboratory of Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | - Hans Wienk
- Department of Chemistry, NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, The Netherlands
| | | | - Eelco J. P. de Koning
- Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands
- Hubrecht Institute/KNAW and University Medical Center Utrecht, Utrecht, The Netherlands
| | - Johannes L. Bos
- Molecular Cancer Research and Cancer Genomics Netherlands, Center for Molecular Medicine, UMC Utrecht, Utrecht, The Netherlands
| | | | | | | | - Holger Rehmann
- Molecular Cancer Research and Cancer Genomics Netherlands, Center for Molecular Medicine, UMC Utrecht, Utrecht, The Netherlands
- * E-mail:
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33
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Poppinga WJ, Muñoz-Llancao P, González-Billault C, Schmidt M. A-kinase anchoring proteins: cAMP compartmentalization in neurodegenerative and obstructive pulmonary diseases. Br J Pharmacol 2014; 171:5603-23. [PMID: 25132049 PMCID: PMC4290705 DOI: 10.1111/bph.12882] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/14/2014] [Accepted: 08/10/2014] [Indexed: 12/25/2022] Open
Abstract
The universal second messenger cAMP is generated upon stimulation of Gs protein-coupled receptors, such as the β2 -adreneoceptor, and leads to the activation of PKA, the major cAMP effector protein. PKA oscillates between an on and off state and thereby regulates a plethora of distinct biological responses. The broad activation pattern of PKA and its contribution to several distinct cellular functions lead to the introduction of the concept of compartmentalization of cAMP. A-kinase anchoring proteins (AKAPs) are of central importance due to their unique ability to directly and/or indirectly interact with proteins that either determine the cellular content of cAMP, such as β2 -adrenoceptors, ACs and PDEs, or are regulated by cAMP such as the exchange protein directly activated by cAMP. We report on lessons learned from neurons indicating that maintenance of cAMP compartmentalization by AKAP5 is linked to neurotransmission, learning and memory. Disturbance of cAMP compartments seem to be linked to neurodegenerative disease including Alzheimer's disease. We translate this knowledge to compartmentalized cAMP signalling in the lung. Next to AKAP5, we focus here on AKAP12 and Ezrin (AKAP78). These topics will be highlighted in the context of the development of novel pharmacological interventions to tackle AKAP-dependent compartmentalization.
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Affiliation(s)
- W J Poppinga
- Department of Molecular Pharmacology, University of GroningenGroningen, The Netherlands
- Groningen Research Institute for Asthma and COPD (GRIAC), University Medical Center Groningen, University of GroningenGroningen, The Netherlands
| | - P Muñoz-Llancao
- Department of Molecular Pharmacology, University of GroningenGroningen, The Netherlands
- Laboratory of Cell and Neuronal Dynamics (Cenedyn), Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile
- Department of Neuroscience, Section Medical Physiology, University Medical Center Groningen, University of GroningenGroningen, The Netherlands
| | - C González-Billault
- Laboratory of Cell and Neuronal Dynamics (Cenedyn), Department of Biology, Faculty of Sciences, Universidad de ChileSantiago, Chile
| | - M Schmidt
- Department of Molecular Pharmacology, University of GroningenGroningen, The Netherlands
- Groningen Research Institute for Asthma and COPD (GRIAC), University Medical Center Groningen, University of GroningenGroningen, The Netherlands
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Mediero A, Perez-Aso M, Cronstein BN. Activation of EPAC1/2 is essential for osteoclast formation by modulating NFκB nuclear translocation and actin cytoskeleton rearrangements. FASEB J 2014; 28:4901-13. [PMID: 25122553 DOI: 10.1096/fj.14-255703] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Bisphosphonates inhibit osteoclast differentiation/function via inhibition of Rap1A isoprenylation. As Rap1 is the effector of exchange protein directly activated by cAMP (EPAC) proteins, we determined the role of EPAC in osteoclast differentiation. We examined osteoclast differentiation as the number of primary murine/human bone-marrow precursors that differentiated into multinucleated TRAP-positive cells in the presence of EPAC-selective stimulus (8-pCTP-2'-O-Me-cAMP, 100 μM; 8-pCTP-2'-O-Me-cAMP-AM, 1 μM) or inhibitor brefeldin A (BFA), ESI-05, and ESI-09 (10 μM each). Rap1 activity was assessed, and signaling events, as well as differentiation in EPAC1/2-knockdown RAW264.7 cells, were studied. Direct EPAC1/2 stimulation significantly increased osteoclast differentiation, whereas EPAC1/2 inhibition diminished differentiation (113 ± 6%, P < 0.05, and 42 ± 10%, P < 0.001, of basal, respectively). Rap1 activation was maximal 15 min after RANKL stimulation (147 ± 9% of basal, P < 0.001), whereas silencing of EPAC1/2 diminished activated Rap1 (43 ± 13 and 20 ± 15% of control, P < 0.001) and NFkB nuclear translocation. TRAP-staining revealed no osteoclast differentiation in EPAC1/2-KO cells. Cathepsin K, NFATc1, and osteopontin mRNA expression decreased in EPAC1/2-KO cells when compared to control. RhoA, cdc42, Rac1, and FAK were activated in an EPAC1/2-dependent manner, and there was diminished cytoskeletal assembly in EPAC1/2-KO cells. In summary, EPAC1 and EPAC2 are critical signaling intermediates in osteoclast differentiation that permit RANKL-stimulated NFkB nuclear translocation and actin rearrangements. Targeting this signaling intermediate may diminish bone destruction in inflammatory arthritis.
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Affiliation(s)
- Aránzazu Mediero
- Department of Medicine, Division of Translational Medicine, New York University School of Medicine, New York, New York, USA
| | - Miguel Perez-Aso
- Department of Medicine, Division of Translational Medicine, New York University School of Medicine, New York, New York, USA
| | - Bruce N Cronstein
- Department of Medicine, Division of Translational Medicine, New York University School of Medicine, New York, New York, USA
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